drm: Handle ->disable_plane failures correctly

[firefly-linux-kernel-4.4.55.git] / drivers / gpu / drm / drm_crtc.c

/*
 * Copyright (c) 2006-2008 Intel Corporation
 * Copyright (c) 2007 Dave Airlie <airlied@linux.ie>
 * Copyright (c) 2008 Red Hat Inc.
 *
 * DRM core CRTC related functions
 *
 * Permission to use, copy, modify, distribute, and sell this software and its
 * documentation for any purpose is hereby granted without fee, provided that
 * the above copyright notice appear in all copies and that both that copyright
 * notice and this permission notice appear in supporting documentation, and
 * that the name of the copyright holders not be used in advertising or
 * publicity pertaining to distribution of the software without specific,
 * written prior permission.  The copyright holders make no representations
 * about the suitability of this software for any purpose.  It is provided "as
 * is" without express or implied warranty.
 *
 * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
 * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
 * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
 * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
 * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
 * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
 * OF THIS SOFTWARE.
 *
 * Authors:
 *      Keith Packard
 *      Eric Anholt <eric@anholt.net>
 *      Dave Airlie <airlied@linux.ie>
 *      Jesse Barnes <jesse.barnes@intel.com>
 */
#include <linux/ctype.h>
#include <linux/list.h>
#include <linux/slab.h>
#include <linux/export.h>
#include <drm/drmP.h>
#include <drm/drm_crtc.h>
#include <drm/drm_edid.h>
#include <drm/drm_fourcc.h>

#include "drm_crtc_internal.h"

/**
 * drm_modeset_lock_all - take all modeset locks
 * @dev: drm device
 *
 * This function takes all modeset locks, suitable where a more fine-grained
 * scheme isn't (yet) implemented. Locks must be dropped with
 * drm_modeset_unlock_all.
 */
void drm_modeset_lock_all(struct drm_device *dev)
{
        struct drm_crtc *crtc;

        mutex_lock(&dev->mode_config.mutex);

        list_for_each_entry(crtc, &dev->mode_config.crtc_list, head)
                mutex_lock_nest_lock(&crtc->mutex, &dev->mode_config.mutex);
}
EXPORT_SYMBOL(drm_modeset_lock_all);

/**
 * drm_modeset_unlock_all - drop all modeset locks
 * @dev: device
 *
 * This function drop all modeset locks taken by drm_modeset_lock_all.
 */
void drm_modeset_unlock_all(struct drm_device *dev)
{
        struct drm_crtc *crtc;

        list_for_each_entry(crtc, &dev->mode_config.crtc_list, head)
                mutex_unlock(&crtc->mutex);

        mutex_unlock(&dev->mode_config.mutex);
}
EXPORT_SYMBOL(drm_modeset_unlock_all);

/**
 * drm_warn_on_modeset_not_all_locked - check that all modeset locks are locked
 * @dev: device
 *
 * Useful as a debug assert.
 */
void drm_warn_on_modeset_not_all_locked(struct drm_device *dev)
{
        struct drm_crtc *crtc;

        /* Locking is currently fubar in the panic handler. */
        if (oops_in_progress)
                return;

        list_for_each_entry(crtc, &dev->mode_config.crtc_list, head)
                WARN_ON(!mutex_is_locked(&crtc->mutex));

        WARN_ON(!mutex_is_locked(&dev->mode_config.mutex));
}
EXPORT_SYMBOL(drm_warn_on_modeset_not_all_locked);

/* Avoid boilerplate.  I'm tired of typing. */
#define DRM_ENUM_NAME_FN(fnname, list)                          \
        const char *fnname(int val)                             \
        {                                                       \
                int i;                                          \
                for (i = 0; i < ARRAY_SIZE(list); i++) {        \
                        if (list[i].type == val)                \
                                return list[i].name;            \
                }                                               \
                return "(unknown)";                             \
        }

/*
 * Global properties
 */
static const struct drm_prop_enum_list drm_dpms_enum_list[] =
{       { DRM_MODE_DPMS_ON, "On" },
        { DRM_MODE_DPMS_STANDBY, "Standby" },
        { DRM_MODE_DPMS_SUSPEND, "Suspend" },
        { DRM_MODE_DPMS_OFF, "Off" }
};

DRM_ENUM_NAME_FN(drm_get_dpms_name, drm_dpms_enum_list)

static const struct drm_prop_enum_list drm_plane_type_enum_list[] =
{
        { DRM_PLANE_TYPE_OVERLAY, "Overlay" },
        { DRM_PLANE_TYPE_PRIMARY, "Primary" },
        { DRM_PLANE_TYPE_CURSOR, "Cursor" },
};

/*
 * Optional properties
 */
static const struct drm_prop_enum_list drm_scaling_mode_enum_list[] =
{
        { DRM_MODE_SCALE_NONE, "None" },
        { DRM_MODE_SCALE_FULLSCREEN, "Full" },
        { DRM_MODE_SCALE_CENTER, "Center" },
        { DRM_MODE_SCALE_ASPECT, "Full aspect" },
};

/*
 * Non-global properties, but "required" for certain connectors.
 */
static const struct drm_prop_enum_list drm_dvi_i_select_enum_list[] =
{
        { DRM_MODE_SUBCONNECTOR_Automatic, "Automatic" }, /* DVI-I and TV-out */
        { DRM_MODE_SUBCONNECTOR_DVID,      "DVI-D"     }, /* DVI-I  */
        { DRM_MODE_SUBCONNECTOR_DVIA,      "DVI-A"     }, /* DVI-I  */
};

DRM_ENUM_NAME_FN(drm_get_dvi_i_select_name, drm_dvi_i_select_enum_list)

static const struct drm_prop_enum_list drm_dvi_i_subconnector_enum_list[] =
{
        { DRM_MODE_SUBCONNECTOR_Unknown,   "Unknown"   }, /* DVI-I and TV-out */
        { DRM_MODE_SUBCONNECTOR_DVID,      "DVI-D"     }, /* DVI-I  */
        { DRM_MODE_SUBCONNECTOR_DVIA,      "DVI-A"     }, /* DVI-I  */
};

DRM_ENUM_NAME_FN(drm_get_dvi_i_subconnector_name,
                 drm_dvi_i_subconnector_enum_list)

static const struct drm_prop_enum_list drm_tv_select_enum_list[] =
{
        { DRM_MODE_SUBCONNECTOR_Automatic, "Automatic" }, /* DVI-I and TV-out */
        { DRM_MODE_SUBCONNECTOR_Composite, "Composite" }, /* TV-out */
        { DRM_MODE_SUBCONNECTOR_SVIDEO,    "SVIDEO"    }, /* TV-out */
        { DRM_MODE_SUBCONNECTOR_Component, "Component" }, /* TV-out */
        { DRM_MODE_SUBCONNECTOR_SCART,     "SCART"     }, /* TV-out */
};

DRM_ENUM_NAME_FN(drm_get_tv_select_name, drm_tv_select_enum_list)

static const struct drm_prop_enum_list drm_tv_subconnector_enum_list[] =
{
        { DRM_MODE_SUBCONNECTOR_Unknown,   "Unknown"   }, /* DVI-I and TV-out */
        { DRM_MODE_SUBCONNECTOR_Composite, "Composite" }, /* TV-out */
        { DRM_MODE_SUBCONNECTOR_SVIDEO,    "SVIDEO"    }, /* TV-out */
        { DRM_MODE_SUBCONNECTOR_Component, "Component" }, /* TV-out */
        { DRM_MODE_SUBCONNECTOR_SCART,     "SCART"     }, /* TV-out */
};

DRM_ENUM_NAME_FN(drm_get_tv_subconnector_name,
                 drm_tv_subconnector_enum_list)

static const struct drm_prop_enum_list drm_dirty_info_enum_list[] = {
        { DRM_MODE_DIRTY_OFF,      "Off"      },
        { DRM_MODE_DIRTY_ON,       "On"       },
        { DRM_MODE_DIRTY_ANNOTATE, "Annotate" },
};

struct drm_conn_prop_enum_list {
        int type;
        const char *name;
        struct ida ida;
};

/*
 * Connector and encoder types.
 */
static struct drm_conn_prop_enum_list drm_connector_enum_list[] =
{       { DRM_MODE_CONNECTOR_Unknown, "Unknown" },
        { DRM_MODE_CONNECTOR_VGA, "VGA" },
        { DRM_MODE_CONNECTOR_DVII, "DVI-I" },
        { DRM_MODE_CONNECTOR_DVID, "DVI-D" },
        { DRM_MODE_CONNECTOR_DVIA, "DVI-A" },
        { DRM_MODE_CONNECTOR_Composite, "Composite" },
        { DRM_MODE_CONNECTOR_SVIDEO, "SVIDEO" },
        { DRM_MODE_CONNECTOR_LVDS, "LVDS" },
        { DRM_MODE_CONNECTOR_Component, "Component" },
        { DRM_MODE_CONNECTOR_9PinDIN, "DIN" },
        { DRM_MODE_CONNECTOR_DisplayPort, "DP" },
        { DRM_MODE_CONNECTOR_HDMIA, "HDMI-A" },
        { DRM_MODE_CONNECTOR_HDMIB, "HDMI-B" },
        { DRM_MODE_CONNECTOR_TV, "TV" },
        { DRM_MODE_CONNECTOR_eDP, "eDP" },
        { DRM_MODE_CONNECTOR_VIRTUAL, "Virtual" },
        { DRM_MODE_CONNECTOR_DSI, "DSI" },
};

static const struct drm_prop_enum_list drm_encoder_enum_list[] =
{       { DRM_MODE_ENCODER_NONE, "None" },
        { DRM_MODE_ENCODER_DAC, "DAC" },
        { DRM_MODE_ENCODER_TMDS, "TMDS" },
        { DRM_MODE_ENCODER_LVDS, "LVDS" },
        { DRM_MODE_ENCODER_TVDAC, "TV" },
        { DRM_MODE_ENCODER_VIRTUAL, "Virtual" },
        { DRM_MODE_ENCODER_DSI, "DSI" },
};

static const struct drm_prop_enum_list drm_subpixel_enum_list[] =
{
        { SubPixelUnknown, "Unknown" },
        { SubPixelHorizontalRGB, "Horizontal RGB" },
        { SubPixelHorizontalBGR, "Horizontal BGR" },
        { SubPixelVerticalRGB, "Vertical RGB" },
        { SubPixelVerticalBGR, "Vertical BGR" },
        { SubPixelNone, "None" },
};

void drm_connector_ida_init(void)
{
        int i;

        for (i = 0; i < ARRAY_SIZE(drm_connector_enum_list); i++)
                ida_init(&drm_connector_enum_list[i].ida);
}

void drm_connector_ida_destroy(void)
{
        int i;

        for (i = 0; i < ARRAY_SIZE(drm_connector_enum_list); i++)
                ida_destroy(&drm_connector_enum_list[i].ida);
}

/**
 * drm_get_encoder_name - return a string for encoder
 * @encoder: encoder to compute name of
 *
 * Note that the buffer used by this function is globally shared and owned by
 * the function itself.
 *
 * FIXME: This isn't really multithreading safe.
 */
const char *drm_get_encoder_name(const struct drm_encoder *encoder)
{
        static char buf[32];

        snprintf(buf, 32, "%s-%d",
                 drm_encoder_enum_list[encoder->encoder_type].name,
                 encoder->base.id);
        return buf;
}
EXPORT_SYMBOL(drm_get_encoder_name);

/**
 * drm_get_connector_name - return a string for connector
 * @connector: connector to compute name of
 *
 * Note that the buffer used by this function is globally shared and owned by
 * the function itself.
 *
 * FIXME: This isn't really multithreading safe.
 */
const char *drm_get_connector_name(const struct drm_connector *connector)
{
        static char buf[32];

        snprintf(buf, 32, "%s-%d",
                 drm_connector_enum_list[connector->connector_type].name,
                 connector->connector_type_id);
        return buf;
}
EXPORT_SYMBOL(drm_get_connector_name);

/**
 * drm_get_connector_status_name - return a string for connector status
 * @status: connector status to compute name of
 *
 * In contrast to the other drm_get_*_name functions this one here returns a
 * const pointer and hence is threadsafe.
 */
const char *drm_get_connector_status_name(enum drm_connector_status status)
{
        if (status == connector_status_connected)
                return "connected";
        else if (status == connector_status_disconnected)
                return "disconnected";
        else
                return "unknown";
}
EXPORT_SYMBOL(drm_get_connector_status_name);

/**
 * drm_get_subpixel_order_name - return a string for a given subpixel enum
 * @order: enum of subpixel_order
 *
 * Note you could abuse this and return something out of bounds, but that
 * would be a caller error.  No unscrubbed user data should make it here.
 */
const char *drm_get_subpixel_order_name(enum subpixel_order order)
{
        return drm_subpixel_enum_list[order].name;
}
EXPORT_SYMBOL(drm_get_subpixel_order_name);

static char printable_char(int c)
{
        return isascii(c) && isprint(c) ? c : '?';
}

/**
 * drm_get_format_name - return a string for drm fourcc format
 * @format: format to compute name of
 *
 * Note that the buffer used by this function is globally shared and owned by
 * the function itself.
 *
 * FIXME: This isn't really multithreading safe.
 */
const char *drm_get_format_name(uint32_t format)
{
        static char buf[32];

        snprintf(buf, sizeof(buf),
                 "%c%c%c%c %s-endian (0x%08x)",
                 printable_char(format & 0xff),
                 printable_char((format >> 8) & 0xff),
                 printable_char((format >> 16) & 0xff),
                 printable_char((format >> 24) & 0x7f),
                 format & DRM_FORMAT_BIG_ENDIAN ? "big" : "little",
                 format);

        return buf;
}
EXPORT_SYMBOL(drm_get_format_name);

/**
 * drm_mode_object_get - allocate a new modeset identifier
 * @dev: DRM device
 * @obj: object pointer, used to generate unique ID
 * @obj_type: object type
 *
 * Create a unique identifier based on @ptr in @dev's identifier space.  Used
 * for tracking modes, CRTCs and connectors. Note that despite the _get postfix
 * modeset identifiers are _not_ reference counted. Hence don't use this for
 * reference counted modeset objects like framebuffers.
 *
 * Returns:
 * New unique (relative to other objects in @dev) integer identifier for the
 * object.
 */
int drm_mode_object_get(struct drm_device *dev,
                        struct drm_mode_object *obj, uint32_t obj_type)
{
        int ret;

        mutex_lock(&dev->mode_config.idr_mutex);
        ret = idr_alloc(&dev->mode_config.crtc_idr, obj, 1, 0, GFP_KERNEL);
        if (ret >= 0) {
                /*
                 * Set up the object linking under the protection of the idr
                 * lock so that other users can't see inconsistent state.
                 */
                obj->id = ret;
                obj->type = obj_type;
        }
        mutex_unlock(&dev->mode_config.idr_mutex);

        return ret < 0 ? ret : 0;
}

/**
 * drm_mode_object_put - free a modeset identifer
 * @dev: DRM device
 * @object: object to free
 *
 * Free @id from @dev's unique identifier pool. Note that despite the _get
 * postfix modeset identifiers are _not_ reference counted. Hence don't use this
 * for reference counted modeset objects like framebuffers.
 */
void drm_mode_object_put(struct drm_device *dev,
                         struct drm_mode_object *object)
{
        mutex_lock(&dev->mode_config.idr_mutex);
        idr_remove(&dev->mode_config.crtc_idr, object->id);
        mutex_unlock(&dev->mode_config.idr_mutex);
}

/**
 * drm_mode_object_find - look up a drm object with static lifetime
 * @dev: drm device
 * @id: id of the mode object
 * @type: type of the mode object
 *
 * Note that framebuffers cannot be looked up with this functions - since those
 * are reference counted, they need special treatment.
 */
struct drm_mode_object *drm_mode_object_find(struct drm_device *dev,
                uint32_t id, uint32_t type)
{
        struct drm_mode_object *obj = NULL;

        /* Framebuffers are reference counted and need their own lookup
         * function.*/
        WARN_ON(type == DRM_MODE_OBJECT_FB);

        mutex_lock(&dev->mode_config.idr_mutex);
        obj = idr_find(&dev->mode_config.crtc_idr, id);
        if (!obj || (obj->type != type) || (obj->id != id))
                obj = NULL;
        mutex_unlock(&dev->mode_config.idr_mutex);

        return obj;
}
EXPORT_SYMBOL(drm_mode_object_find);

/**
 * drm_framebuffer_init - initialize a framebuffer
 * @dev: DRM device
 * @fb: framebuffer to be initialized
 * @funcs: ... with these functions
 *
 * Allocates an ID for the framebuffer's parent mode object, sets its mode
 * functions & device file and adds it to the master fd list.
 *
 * IMPORTANT:
 * This functions publishes the fb and makes it available for concurrent access
 * by other users. Which means by this point the fb _must_ be fully set up -
 * since all the fb attributes are invariant over its lifetime, no further
 * locking but only correct reference counting is required.
 *
 * Returns:
 * Zero on success, error code on failure.
 */
int drm_framebuffer_init(struct drm_device *dev, struct drm_framebuffer *fb,
                         const struct drm_framebuffer_funcs *funcs)
{
        int ret;

        mutex_lock(&dev->mode_config.fb_lock);
        kref_init(&fb->refcount);
        INIT_LIST_HEAD(&fb->filp_head);
        fb->dev = dev;
        fb->funcs = funcs;

        ret = drm_mode_object_get(dev, &fb->base, DRM_MODE_OBJECT_FB);
        if (ret)
                goto out;

        /* Grab the idr reference. */
        drm_framebuffer_reference(fb);

        dev->mode_config.num_fb++;
        list_add(&fb->head, &dev->mode_config.fb_list);
out:
        mutex_unlock(&dev->mode_config.fb_lock);

        return 0;
}
EXPORT_SYMBOL(drm_framebuffer_init);

static void drm_framebuffer_free(struct kref *kref)
{
        struct drm_framebuffer *fb =
                        container_of(kref, struct drm_framebuffer, refcount);
        fb->funcs->destroy(fb);
}

static struct drm_framebuffer *__drm_framebuffer_lookup(struct drm_device *dev,
                                                        uint32_t id)
{
        struct drm_mode_object *obj = NULL;
        struct drm_framebuffer *fb;

        mutex_lock(&dev->mode_config.idr_mutex);
        obj = idr_find(&dev->mode_config.crtc_idr, id);
        if (!obj || (obj->type != DRM_MODE_OBJECT_FB) || (obj->id != id))
                fb = NULL;
        else
                fb = obj_to_fb(obj);
        mutex_unlock(&dev->mode_config.idr_mutex);

        return fb;
}

/**
 * drm_framebuffer_lookup - look up a drm framebuffer and grab a reference
 * @dev: drm device
 * @id: id of the fb object
 *
 * If successful, this grabs an additional reference to the framebuffer -
 * callers need to make sure to eventually unreference the returned framebuffer
 * again, using @drm_framebuffer_unreference.
 */
struct drm_framebuffer *drm_framebuffer_lookup(struct drm_device *dev,
                                               uint32_t id)
{
        struct drm_framebuffer *fb;

        mutex_lock(&dev->mode_config.fb_lock);
        fb = __drm_framebuffer_lookup(dev, id);
        if (fb)
                drm_framebuffer_reference(fb);
        mutex_unlock(&dev->mode_config.fb_lock);

        return fb;
}
EXPORT_SYMBOL(drm_framebuffer_lookup);

/**
 * drm_framebuffer_unreference - unref a framebuffer
 * @fb: framebuffer to unref
 *
 * This functions decrements the fb's refcount and frees it if it drops to zero.
 */
void drm_framebuffer_unreference(struct drm_framebuffer *fb)
{
        DRM_DEBUG("FB ID: %d\n", fb->base.id);
        kref_put(&fb->refcount, drm_framebuffer_free);
}
EXPORT_SYMBOL(drm_framebuffer_unreference);

/**
 * drm_framebuffer_reference - incr the fb refcnt
 * @fb: framebuffer
 *
 * This functions increments the fb's refcount.
 */
void drm_framebuffer_reference(struct drm_framebuffer *fb)
{
        DRM_DEBUG("FB ID: %d\n", fb->base.id);
        kref_get(&fb->refcount);
}
EXPORT_SYMBOL(drm_framebuffer_reference);

static void drm_framebuffer_free_bug(struct kref *kref)
{
        BUG();
}

static void __drm_framebuffer_unreference(struct drm_framebuffer *fb)
{
        DRM_DEBUG("FB ID: %d\n", fb->base.id);
        kref_put(&fb->refcount, drm_framebuffer_free_bug);
}

/* dev->mode_config.fb_lock must be held! */
static void __drm_framebuffer_unregister(struct drm_device *dev,
                                         struct drm_framebuffer *fb)
{
        mutex_lock(&dev->mode_config.idr_mutex);
        idr_remove(&dev->mode_config.crtc_idr, fb->base.id);
        mutex_unlock(&dev->mode_config.idr_mutex);

        fb->base.id = 0;

        __drm_framebuffer_unreference(fb);
}

/**
 * drm_framebuffer_unregister_private - unregister a private fb from the lookup idr
 * @fb: fb to unregister
 *
 * Drivers need to call this when cleaning up driver-private framebuffers, e.g.
 * those used for fbdev. Note that the caller must hold a reference of it's own,
 * i.e. the object may not be destroyed through this call (since it'll lead to a
 * locking inversion).
 */
void drm_framebuffer_unregister_private(struct drm_framebuffer *fb)
{
        struct drm_device *dev = fb->dev;

        mutex_lock(&dev->mode_config.fb_lock);
        /* Mark fb as reaped and drop idr ref. */
        __drm_framebuffer_unregister(dev, fb);
        mutex_unlock(&dev->mode_config.fb_lock);
}
EXPORT_SYMBOL(drm_framebuffer_unregister_private);

/**
 * drm_framebuffer_cleanup - remove a framebuffer object
 * @fb: framebuffer to remove
 *
 * Cleanup framebuffer. This function is intended to be used from the drivers
 * ->destroy callback. It can also be used to clean up driver private
 *  framebuffers embedded into a larger structure.
 *
 * Note that this function does not remove the fb from active usuage - if it is
 * still used anywhere, hilarity can ensue since userspace could call getfb on
 * the id and get back -EINVAL. Obviously no concern at driver unload time.
 *
 * Also, the framebuffer will not be removed from the lookup idr - for
 * user-created framebuffers this will happen in in the rmfb ioctl. For
 * driver-private objects (e.g. for fbdev) drivers need to explicitly call
 * drm_framebuffer_unregister_private.
 */
void drm_framebuffer_cleanup(struct drm_framebuffer *fb)
{
        struct drm_device *dev = fb->dev;

        mutex_lock(&dev->mode_config.fb_lock);
        list_del(&fb->head);
        dev->mode_config.num_fb--;
        mutex_unlock(&dev->mode_config.fb_lock);
}
EXPORT_SYMBOL(drm_framebuffer_cleanup);

/**
 * drm_framebuffer_remove - remove and unreference a framebuffer object
 * @fb: framebuffer to remove
 *
 * Scans all the CRTCs and planes in @dev's mode_config.  If they're
 * using @fb, removes it, setting it to NULL. Then drops the reference to the
 * passed-in framebuffer. Might take the modeset locks.
 *
 * Note that this function optimizes the cleanup away if the caller holds the
 * last reference to the framebuffer. It is also guaranteed to not take the
 * modeset locks in this case.
 */
void drm_framebuffer_remove(struct drm_framebuffer *fb)
{
        struct drm_device *dev = fb->dev;
        struct drm_crtc *crtc;
        struct drm_plane *plane;
        struct drm_mode_set set;
        int ret;

        WARN_ON(!list_empty(&fb->filp_head));

        /*
         * drm ABI mandates that we remove any deleted framebuffers from active
         * useage. But since most sane clients only remove framebuffers they no
         * longer need, try to optimize this away.
         *
         * Since we're holding a reference ourselves, observing a refcount of 1
         * means that we're the last holder and can skip it. Also, the refcount
         * can never increase from 1 again, so we don't need any barriers or
         * locks.
         *
         * Note that userspace could try to race with use and instate a new
         * usage _after_ we've cleared all current ones. End result will be an
         * in-use fb with fb-id == 0. Userspace is allowed to shoot its own foot
         * in this manner.
         */
        if (atomic_read(&fb->refcount.refcount) > 1) {
                drm_modeset_lock_all(dev);
                /* remove from any CRTC */
                list_for_each_entry(crtc, &dev->mode_config.crtc_list, head) {
                        if (crtc->primary->fb == fb) {
                                /* should turn off the crtc */
                                memset(&set, 0, sizeof(struct drm_mode_set));
                                set.crtc = crtc;
                                set.fb = NULL;
                                ret = drm_mode_set_config_internal(&set);
                                if (ret)
                                        DRM_ERROR("failed to reset crtc %p when fb was deleted\n", crtc);
                        }
                }

                list_for_each_entry(plane, &dev->mode_config.plane_list, head) {
                        if (plane->fb == fb)
                                drm_plane_force_disable(plane);
                }
                drm_modeset_unlock_all(dev);
        }

        drm_framebuffer_unreference(fb);
}
EXPORT_SYMBOL(drm_framebuffer_remove);

/**
 * drm_crtc_init_with_planes - Initialise a new CRTC object with
 *    specified primary and cursor planes.
 * @dev: DRM device
 * @crtc: CRTC object to init
 * @primary: Primary plane for CRTC
 * @cursor: Cursor plane for CRTC
 * @funcs: callbacks for the new CRTC
 *
 * Inits a new object created as base part of a driver crtc object.
 *
 * Returns:
 * Zero on success, error code on failure.
 */
int drm_crtc_init_with_planes(struct drm_device *dev, struct drm_crtc *crtc,
                              struct drm_plane *primary,
                              void *cursor,
                              const struct drm_crtc_funcs *funcs)
{
        int ret;

        crtc->dev = dev;
        crtc->funcs = funcs;
        crtc->invert_dimensions = false;

        drm_modeset_lock_all(dev);
        mutex_init(&crtc->mutex);
        mutex_lock_nest_lock(&crtc->mutex, &dev->mode_config.mutex);

        ret = drm_mode_object_get(dev, &crtc->base, DRM_MODE_OBJECT_CRTC);
        if (ret)
                goto out;

        crtc->base.properties = &crtc->properties;

        list_add_tail(&crtc->head, &dev->mode_config.crtc_list);
        dev->mode_config.num_crtc++;

        crtc->primary = primary;
        if (primary)
                primary->possible_crtcs = 1 << drm_crtc_index(crtc);

 out:
        drm_modeset_unlock_all(dev);

        return ret;
}
EXPORT_SYMBOL(drm_crtc_init_with_planes);

/**
 * drm_crtc_cleanup - Clean up the core crtc usage
 * @crtc: CRTC to cleanup
 *
 * This function cleans up @crtc and removes it from the DRM mode setting
 * core. Note that the function does *not* free the crtc structure itself,
 * this is the responsibility of the caller.
 */
void drm_crtc_cleanup(struct drm_crtc *crtc)
{
        struct drm_device *dev = crtc->dev;

        kfree(crtc->gamma_store);
        crtc->gamma_store = NULL;

        drm_mode_object_put(dev, &crtc->base);
        list_del(&crtc->head);
        dev->mode_config.num_crtc--;
}
EXPORT_SYMBOL(drm_crtc_cleanup);

/**
 * drm_crtc_index - find the index of a registered CRTC
 * @crtc: CRTC to find index for
 *
 * Given a registered CRTC, return the index of that CRTC within a DRM
 * device's list of CRTCs.
 */
unsigned int drm_crtc_index(struct drm_crtc *crtc)
{
        unsigned int index = 0;
        struct drm_crtc *tmp;

        list_for_each_entry(tmp, &crtc->dev->mode_config.crtc_list, head) {
                if (tmp == crtc)
                        return index;

                index++;
        }

        BUG();
}
EXPORT_SYMBOL(drm_crtc_index);

/*
 * drm_mode_remove - remove and free a mode
 * @connector: connector list to modify
 * @mode: mode to remove
 *
 * Remove @mode from @connector's mode list, then free it.
 */
static void drm_mode_remove(struct drm_connector *connector,
                            struct drm_display_mode *mode)
{
        list_del(&mode->head);
        drm_mode_destroy(connector->dev, mode);
}

/**
 * drm_connector_init - Init a preallocated connector
 * @dev: DRM device
 * @connector: the connector to init
 * @funcs: callbacks for this connector
 * @connector_type: user visible type of the connector
 *
 * Initialises a preallocated connector. Connectors should be
 * subclassed as part of driver connector objects.
 *
 * Returns:
 * Zero on success, error code on failure.
 */
int drm_connector_init(struct drm_device *dev,
                       struct drm_connector *connector,
                       const struct drm_connector_funcs *funcs,
                       int connector_type)
{
        int ret;
        struct ida *connector_ida =
                &drm_connector_enum_list[connector_type].ida;

        drm_modeset_lock_all(dev);

        ret = drm_mode_object_get(dev, &connector->base, DRM_MODE_OBJECT_CONNECTOR);
        if (ret)
                goto out;

        connector->base.properties = &connector->properties;
        connector->dev = dev;
        connector->funcs = funcs;
        connector->connector_type = connector_type;
        connector->connector_type_id =
                ida_simple_get(connector_ida, 1, 0, GFP_KERNEL);
        if (connector->connector_type_id < 0) {
                ret = connector->connector_type_id;
                drm_mode_object_put(dev, &connector->base);
                goto out;
        }
        INIT_LIST_HEAD(&connector->probed_modes);
        INIT_LIST_HEAD(&connector->modes);
        connector->edid_blob_ptr = NULL;
        connector->status = connector_status_unknown;

        list_add_tail(&connector->head, &dev->mode_config.connector_list);
        dev->mode_config.num_connector++;

        if (connector_type != DRM_MODE_CONNECTOR_VIRTUAL)
                drm_object_attach_property(&connector->base,
                                              dev->mode_config.edid_property,
                                              0);

        drm_object_attach_property(&connector->base,
                                      dev->mode_config.dpms_property, 0);

 out:
        drm_modeset_unlock_all(dev);

        return ret;
}
EXPORT_SYMBOL(drm_connector_init);

/**
 * drm_connector_cleanup - cleans up an initialised connector
 * @connector: connector to cleanup
 *
 * Cleans up the connector but doesn't free the object.
 */
void drm_connector_cleanup(struct drm_connector *connector)
{
        struct drm_device *dev = connector->dev;
        struct drm_display_mode *mode, *t;

        list_for_each_entry_safe(mode, t, &connector->probed_modes, head)
                drm_mode_remove(connector, mode);

        list_for_each_entry_safe(mode, t, &connector->modes, head)
                drm_mode_remove(connector, mode);

        ida_remove(&drm_connector_enum_list[connector->connector_type].ida,
                   connector->connector_type_id);

        drm_mode_object_put(dev, &connector->base);
        list_del(&connector->head);
        dev->mode_config.num_connector--;
}
EXPORT_SYMBOL(drm_connector_cleanup);

/**
 * drm_connector_unplug_all - unregister connector userspace interfaces
 * @dev: drm device
 *
 * This function unregisters all connector userspace interfaces in sysfs. Should
 * be call when the device is disconnected, e.g. from an usb driver's
 * ->disconnect callback.
 */
void drm_connector_unplug_all(struct drm_device *dev)
{
        struct drm_connector *connector;

        /* taking the mode config mutex ends up in a clash with sysfs */
        list_for_each_entry(connector, &dev->mode_config.connector_list, head)
                drm_sysfs_connector_remove(connector);

}
EXPORT_SYMBOL(drm_connector_unplug_all);

/**
 * drm_bridge_init - initialize a drm transcoder/bridge
 * @dev: drm device
 * @bridge: transcoder/bridge to set up
 * @funcs: bridge function table
 *
 * Initialises a preallocated bridge. Bridges should be
 * subclassed as part of driver connector objects.
 *
 * Returns:
 * Zero on success, error code on failure.
 */
int drm_bridge_init(struct drm_device *dev, struct drm_bridge *bridge,
                const struct drm_bridge_funcs *funcs)
{
        int ret;

        drm_modeset_lock_all(dev);

        ret = drm_mode_object_get(dev, &bridge->base, DRM_MODE_OBJECT_BRIDGE);
        if (ret)
                goto out;

        bridge->dev = dev;
        bridge->funcs = funcs;

        list_add_tail(&bridge->head, &dev->mode_config.bridge_list);
        dev->mode_config.num_bridge++;

 out:
        drm_modeset_unlock_all(dev);
        return ret;
}
EXPORT_SYMBOL(drm_bridge_init);

/**
 * drm_bridge_cleanup - cleans up an initialised bridge
 * @bridge: bridge to cleanup
 *
 * Cleans up the bridge but doesn't free the object.
 */
void drm_bridge_cleanup(struct drm_bridge *bridge)
{
        struct drm_device *dev = bridge->dev;

        drm_modeset_lock_all(dev);
        drm_mode_object_put(dev, &bridge->base);
        list_del(&bridge->head);
        dev->mode_config.num_bridge--;
        drm_modeset_unlock_all(dev);
}
EXPORT_SYMBOL(drm_bridge_cleanup);

/**
 * drm_encoder_init - Init a preallocated encoder
 * @dev: drm device
 * @encoder: the encoder to init
 * @funcs: callbacks for this encoder
 * @encoder_type: user visible type of the encoder
 *
 * Initialises a preallocated encoder. Encoder should be
 * subclassed as part of driver encoder objects.
 *
 * Returns:
 * Zero on success, error code on failure.
 */
int drm_encoder_init(struct drm_device *dev,
                      struct drm_encoder *encoder,
                      const struct drm_encoder_funcs *funcs,
                      int encoder_type)
{
        int ret;

        drm_modeset_lock_all(dev);

        ret = drm_mode_object_get(dev, &encoder->base, DRM_MODE_OBJECT_ENCODER);
        if (ret)
                goto out;

        encoder->dev = dev;
        encoder->encoder_type = encoder_type;
        encoder->funcs = funcs;

        list_add_tail(&encoder->head, &dev->mode_config.encoder_list);
        dev->mode_config.num_encoder++;

 out:
        drm_modeset_unlock_all(dev);

        return ret;
}
EXPORT_SYMBOL(drm_encoder_init);

/**
 * drm_encoder_cleanup - cleans up an initialised encoder
 * @encoder: encoder to cleanup
 *
 * Cleans up the encoder but doesn't free the object.
 */
void drm_encoder_cleanup(struct drm_encoder *encoder)
{
        struct drm_device *dev = encoder->dev;
        drm_modeset_lock_all(dev);
        drm_mode_object_put(dev, &encoder->base);
        list_del(&encoder->head);
        dev->mode_config.num_encoder--;
        drm_modeset_unlock_all(dev);
}
EXPORT_SYMBOL(drm_encoder_cleanup);

/**
 * drm_universal_plane_init - Initialize a new universal plane object
 * @dev: DRM device
 * @plane: plane object to init
 * @possible_crtcs: bitmask of possible CRTCs
 * @funcs: callbacks for the new plane
 * @formats: array of supported formats (%DRM_FORMAT_*)
 * @format_count: number of elements in @formats
 * @type: type of plane (overlay, primary, cursor)
 *
 * Initializes a plane object of type @type.
 *
 * Returns:
 * Zero on success, error code on failure.
 */
int drm_universal_plane_init(struct drm_device *dev, struct drm_plane *plane,
                             unsigned long possible_crtcs,
                             const struct drm_plane_funcs *funcs,
                             const uint32_t *formats, uint32_t format_count,
                             enum drm_plane_type type)
{
        int ret;

        drm_modeset_lock_all(dev);

        ret = drm_mode_object_get(dev, &plane->base, DRM_MODE_OBJECT_PLANE);
        if (ret)
                goto out;

        plane->base.properties = &plane->properties;
        plane->dev = dev;
        plane->funcs = funcs;
        plane->format_types = kmalloc(sizeof(uint32_t) * format_count,
                                      GFP_KERNEL);
        if (!plane->format_types) {
                DRM_DEBUG_KMS("out of memory when allocating plane\n");
                drm_mode_object_put(dev, &plane->base);
                ret = -ENOMEM;
                goto out;
        }

        memcpy(plane->format_types, formats, format_count * sizeof(uint32_t));
        plane->format_count = format_count;
        plane->possible_crtcs = possible_crtcs;
        plane->type = type;

        list_add_tail(&plane->head, &dev->mode_config.plane_list);
        dev->mode_config.num_total_plane++;
        if (plane->type == DRM_PLANE_TYPE_OVERLAY)
                dev->mode_config.num_overlay_plane++;

        drm_object_attach_property(&plane->base,
                                   dev->mode_config.plane_type_property,
                                   plane->type);

 out:
        drm_modeset_unlock_all(dev);

        return ret;
}
EXPORT_SYMBOL(drm_universal_plane_init);

/**
 * drm_plane_init - Initialize a legacy plane
 * @dev: DRM device
 * @plane: plane object to init
 * @possible_crtcs: bitmask of possible CRTCs
 * @funcs: callbacks for the new plane
 * @formats: array of supported formats (%DRM_FORMAT_*)
 * @format_count: number of elements in @formats
 * @is_primary: plane type (primary vs overlay)
 *
 * Legacy API to initialize a DRM plane.
 *
 * New drivers should call drm_universal_plane_init() instead.
 *
 * Returns:
 * Zero on success, error code on failure.
 */
int drm_plane_init(struct drm_device *dev, struct drm_plane *plane,
                   unsigned long possible_crtcs,
                   const struct drm_plane_funcs *funcs,
                   const uint32_t *formats, uint32_t format_count,
                   bool is_primary)
{
        enum drm_plane_type type;

        type = is_primary ? DRM_PLANE_TYPE_PRIMARY : DRM_PLANE_TYPE_OVERLAY;
        return drm_universal_plane_init(dev, plane, possible_crtcs, funcs,
                                        formats, format_count, type);
}
EXPORT_SYMBOL(drm_plane_init);

/**
 * drm_plane_cleanup - Clean up the core plane usage
 * @plane: plane to cleanup
 *
 * This function cleans up @plane and removes it from the DRM mode setting
 * core. Note that the function does *not* free the plane structure itself,
 * this is the responsibility of the caller.
 */
void drm_plane_cleanup(struct drm_plane *plane)
{
        struct drm_device *dev = plane->dev;

        drm_modeset_lock_all(dev);
        kfree(plane->format_types);
        drm_mode_object_put(dev, &plane->base);

        BUG_ON(list_empty(&plane->head));

        list_del(&plane->head);
        dev->mode_config.num_total_plane--;
        if (plane->type == DRM_PLANE_TYPE_OVERLAY)
                dev->mode_config.num_overlay_plane--;
        drm_modeset_unlock_all(dev);
}
EXPORT_SYMBOL(drm_plane_cleanup);

/**
 * drm_plane_force_disable - Forcibly disable a plane
 * @plane: plane to disable
 *
 * Forces the plane to be disabled.
 *
 * Used when the plane's current framebuffer is destroyed,
 * and when restoring fbdev mode.
 */
void drm_plane_force_disable(struct drm_plane *plane)
{
        struct drm_framebuffer *old_fb = plane->fb;
        int ret;

        if (!old_fb)
                return;

        ret = plane->funcs->disable_plane(plane);
        if (ret) {
                DRM_ERROR("failed to disable plane with busy fb\n");
                return;
        }
        /* disconnect the plane from the fb and crtc: */
        __drm_framebuffer_unreference(old_fb);
        plane->fb = NULL;
        plane->crtc = NULL;
}
EXPORT_SYMBOL(drm_plane_force_disable);

static int drm_mode_create_standard_connector_properties(struct drm_device *dev)
{
        struct drm_property *edid;
        struct drm_property *dpms;

        /*
         * Standard properties (apply to all connectors)
         */
        edid = drm_property_create(dev, DRM_MODE_PROP_BLOB |
                                   DRM_MODE_PROP_IMMUTABLE,
                                   "EDID", 0);
        dev->mode_config.edid_property = edid;

        dpms = drm_property_create_enum(dev, 0,
                                   "DPMS", drm_dpms_enum_list,
                                   ARRAY_SIZE(drm_dpms_enum_list));
        dev->mode_config.dpms_property = dpms;

        return 0;
}

static int drm_mode_create_standard_plane_properties(struct drm_device *dev)
{
        struct drm_property *type;

        /*
         * Standard properties (apply to all planes)
         */
        type = drm_property_create_enum(dev, DRM_MODE_PROP_IMMUTABLE,
                                        "type", drm_plane_type_enum_list,
                                        ARRAY_SIZE(drm_plane_type_enum_list));
        dev->mode_config.plane_type_property = type;

        return 0;
}

/**
 * drm_mode_create_dvi_i_properties - create DVI-I specific connector properties
 * @dev: DRM device
 *
 * Called by a driver the first time a DVI-I connector is made.
 */
int drm_mode_create_dvi_i_properties(struct drm_device *dev)
{
        struct drm_property *dvi_i_selector;
        struct drm_property *dvi_i_subconnector;

        if (dev->mode_config.dvi_i_select_subconnector_property)
                return 0;

        dvi_i_selector =
                drm_property_create_enum(dev, 0,
                                    "select subconnector",
                                    drm_dvi_i_select_enum_list,
                                    ARRAY_SIZE(drm_dvi_i_select_enum_list));
        dev->mode_config.dvi_i_select_subconnector_property = dvi_i_selector;

        dvi_i_subconnector = drm_property_create_enum(dev, DRM_MODE_PROP_IMMUTABLE,
                                    "subconnector",
                                    drm_dvi_i_subconnector_enum_list,
                                    ARRAY_SIZE(drm_dvi_i_subconnector_enum_list));
        dev->mode_config.dvi_i_subconnector_property = dvi_i_subconnector;

        return 0;
}
EXPORT_SYMBOL(drm_mode_create_dvi_i_properties);

/**
 * drm_create_tv_properties - create TV specific connector properties
 * @dev: DRM device
 * @num_modes: number of different TV formats (modes) supported
 * @modes: array of pointers to strings containing name of each format
 *
 * Called by a driver's TV initialization routine, this function creates
 * the TV specific connector properties for a given device.  Caller is
 * responsible for allocating a list of format names and passing them to
 * this routine.
 */
int drm_mode_create_tv_properties(struct drm_device *dev, int num_modes,
                                  char *modes[])
{
        struct drm_property *tv_selector;
        struct drm_property *tv_subconnector;
        int i;

        if (dev->mode_config.tv_select_subconnector_property)
                return 0;

        /*
         * Basic connector properties
         */
        tv_selector = drm_property_create_enum(dev, 0,
                                          "select subconnector",
                                          drm_tv_select_enum_list,
                                          ARRAY_SIZE(drm_tv_select_enum_list));
        dev->mode_config.tv_select_subconnector_property = tv_selector;

        tv_subconnector =
                drm_property_create_enum(dev, DRM_MODE_PROP_IMMUTABLE,
                                    "subconnector",
                                    drm_tv_subconnector_enum_list,
                                    ARRAY_SIZE(drm_tv_subconnector_enum_list));
        dev->mode_config.tv_subconnector_property = tv_subconnector;

        /*
         * Other, TV specific properties: margins & TV modes.
         */
        dev->mode_config.tv_left_margin_property =
                drm_property_create_range(dev, 0, "left margin", 0, 100);

        dev->mode_config.tv_right_margin_property =
                drm_property_create_range(dev, 0, "right margin", 0, 100);

        dev->mode_config.tv_top_margin_property =
                drm_property_create_range(dev, 0, "top margin", 0, 100);

        dev->mode_config.tv_bottom_margin_property =
                drm_property_create_range(dev, 0, "bottom margin", 0, 100);

        dev->mode_config.tv_mode_property =
                drm_property_create(dev, DRM_MODE_PROP_ENUM,
                                    "mode", num_modes);
        for (i = 0; i < num_modes; i++)
                drm_property_add_enum(dev->mode_config.tv_mode_property, i,
                                      i, modes[i]);

        dev->mode_config.tv_brightness_property =
                drm_property_create_range(dev, 0, "brightness", 0, 100);

        dev->mode_config.tv_contrast_property =
                drm_property_create_range(dev, 0, "contrast", 0, 100);

        dev->mode_config.tv_flicker_reduction_property =
                drm_property_create_range(dev, 0, "flicker reduction", 0, 100);

        dev->mode_config.tv_overscan_property =
                drm_property_create_range(dev, 0, "overscan", 0, 100);

        dev->mode_config.tv_saturation_property =
                drm_property_create_range(dev, 0, "saturation", 0, 100);

        dev->mode_config.tv_hue_property =
                drm_property_create_range(dev, 0, "hue", 0, 100);

        return 0;
}
EXPORT_SYMBOL(drm_mode_create_tv_properties);

/**
 * drm_mode_create_scaling_mode_property - create scaling mode property
 * @dev: DRM device
 *
 * Called by a driver the first time it's needed, must be attached to desired
 * connectors.
 */
int drm_mode_create_scaling_mode_property(struct drm_device *dev)
{
        struct drm_property *scaling_mode;

        if (dev->mode_config.scaling_mode_property)
                return 0;

        scaling_mode =
                drm_property_create_enum(dev, 0, "scaling mode",
                                drm_scaling_mode_enum_list,
                                    ARRAY_SIZE(drm_scaling_mode_enum_list));

        dev->mode_config.scaling_mode_property = scaling_mode;

        return 0;
}
EXPORT_SYMBOL(drm_mode_create_scaling_mode_property);

/**
 * drm_mode_create_dirty_property - create dirty property
 * @dev: DRM device
 *
 * Called by a driver the first time it's needed, must be attached to desired
 * connectors.
 */
int drm_mode_create_dirty_info_property(struct drm_device *dev)
{
        struct drm_property *dirty_info;

        if (dev->mode_config.dirty_info_property)
                return 0;

        dirty_info =
                drm_property_create_enum(dev, DRM_MODE_PROP_IMMUTABLE,
                                    "dirty",
                                    drm_dirty_info_enum_list,
                                    ARRAY_SIZE(drm_dirty_info_enum_list));
        dev->mode_config.dirty_info_property = dirty_info;

        return 0;
}
EXPORT_SYMBOL(drm_mode_create_dirty_info_property);

static int drm_mode_group_init(struct drm_device *dev, struct drm_mode_group *group)
{
        uint32_t total_objects = 0;

        total_objects += dev->mode_config.num_crtc;
        total_objects += dev->mode_config.num_connector;
        total_objects += dev->mode_config.num_encoder;
        total_objects += dev->mode_config.num_bridge;

        group->id_list = kzalloc(total_objects * sizeof(uint32_t), GFP_KERNEL);
        if (!group->id_list)
                return -ENOMEM;

        group->num_crtcs = 0;
        group->num_connectors = 0;
        group->num_encoders = 0;
        group->num_bridges = 0;
        return 0;
}

/*
 * NOTE: Driver's shouldn't ever call drm_mode_group_init_legacy_group - it is
 * the drm core's responsibility to set up mode control groups.
 */
int drm_mode_group_init_legacy_group(struct drm_device *dev,
                                     struct drm_mode_group *group)
{
        struct drm_crtc *crtc;
        struct drm_encoder *encoder;
        struct drm_connector *connector;
        struct drm_bridge *bridge;
        int ret;

        if ((ret = drm_mode_group_init(dev, group)))
                return ret;

        list_for_each_entry(crtc, &dev->mode_config.crtc_list, head)
                group->id_list[group->num_crtcs++] = crtc->base.id;

        list_for_each_entry(encoder, &dev->mode_config.encoder_list, head)
                group->id_list[group->num_crtcs + group->num_encoders++] =
                encoder->base.id;

        list_for_each_entry(connector, &dev->mode_config.connector_list, head)
                group->id_list[group->num_crtcs + group->num_encoders +
                               group->num_connectors++] = connector->base.id;

        list_for_each_entry(bridge, &dev->mode_config.bridge_list, head)
                group->id_list[group->num_crtcs + group->num_encoders +
                               group->num_connectors + group->num_bridges++] =
                                        bridge->base.id;

        return 0;
}
EXPORT_SYMBOL(drm_mode_group_init_legacy_group);

/**
 * drm_crtc_convert_to_umode - convert a drm_display_mode into a modeinfo
 * @out: drm_mode_modeinfo struct to return to the user
 * @in: drm_display_mode to use
 *
 * Convert a drm_display_mode into a drm_mode_modeinfo structure to return to
 * the user.
 */
static void drm_crtc_convert_to_umode(struct drm_mode_modeinfo *out,
                                      const struct drm_display_mode *in)
{
        WARN(in->hdisplay > USHRT_MAX || in->hsync_start > USHRT_MAX ||
             in->hsync_end > USHRT_MAX || in->htotal > USHRT_MAX ||
             in->hskew > USHRT_MAX || in->vdisplay > USHRT_MAX ||
             in->vsync_start > USHRT_MAX || in->vsync_end > USHRT_MAX ||
             in->vtotal > USHRT_MAX || in->vscan > USHRT_MAX,
             "timing values too large for mode info\n");

        out->clock = in->clock;
        out->hdisplay = in->hdisplay;
        out->hsync_start = in->hsync_start;
        out->hsync_end = in->hsync_end;
        out->htotal = in->htotal;
        out->hskew = in->hskew;
        out->vdisplay = in->vdisplay;
        out->vsync_start = in->vsync_start;
        out->vsync_end = in->vsync_end;
        out->vtotal = in->vtotal;
        out->vscan = in->vscan;
        out->vrefresh = in->vrefresh;
        out->flags = in->flags;
        out->type = in->type;
        strncpy(out->name, in->name, DRM_DISPLAY_MODE_LEN);
        out->name[DRM_DISPLAY_MODE_LEN-1] = 0;
}

/**
 * drm_crtc_convert_umode - convert a modeinfo into a drm_display_mode
 * @out: drm_display_mode to return to the user
 * @in: drm_mode_modeinfo to use
 *
 * Convert a drm_mode_modeinfo into a drm_display_mode structure to return to
 * the caller.
 *
 * Returns:
 * Zero on success, errno on failure.
 */
static int drm_crtc_convert_umode(struct drm_display_mode *out,
                                  const struct drm_mode_modeinfo *in)
{
        if (in->clock > INT_MAX || in->vrefresh > INT_MAX)
                return -ERANGE;

        if ((in->flags & DRM_MODE_FLAG_3D_MASK) > DRM_MODE_FLAG_3D_MAX)
                return -EINVAL;

        out->clock = in->clock;
        out->hdisplay = in->hdisplay;
        out->hsync_start = in->hsync_start;
        out->hsync_end = in->hsync_end;
        out->htotal = in->htotal;
        out->hskew = in->hskew;
        out->vdisplay = in->vdisplay;
        out->vsync_start = in->vsync_start;
        out->vsync_end = in->vsync_end;
        out->vtotal = in->vtotal;
        out->vscan = in->vscan;
        out->vrefresh = in->vrefresh;
        out->flags = in->flags;
        out->type = in->type;
        strncpy(out->name, in->name, DRM_DISPLAY_MODE_LEN);
        out->name[DRM_DISPLAY_MODE_LEN-1] = 0;

        return 0;
}

/**
 * drm_mode_getresources - get graphics configuration
 * @dev: drm device for the ioctl
 * @data: data pointer for the ioctl
 * @file_priv: drm file for the ioctl call
 *
 * Construct a set of configuration description structures and return
 * them to the user, including CRTC, connector and framebuffer configuration.
 *
 * Called by the user via ioctl.
 *
 * Returns:
 * Zero on success, errno on failure.
 */
int drm_mode_getresources(struct drm_device *dev, void *data,
                          struct drm_file *file_priv)
{
        struct drm_mode_card_res *card_res = data;
        struct list_head *lh;
        struct drm_framebuffer *fb;
        struct drm_connector *connector;
        struct drm_crtc *crtc;
        struct drm_encoder *encoder;
        int ret = 0;
        int connector_count = 0;
        int crtc_count = 0;
        int fb_count = 0;
        int encoder_count = 0;
        int copied = 0, i;
        uint32_t __user *fb_id;
        uint32_t __user *crtc_id;
        uint32_t __user *connector_id;
        uint32_t __user *encoder_id;
        struct drm_mode_group *mode_group;

        if (!drm_core_check_feature(dev, DRIVER_MODESET))
                return -EINVAL;


        mutex_lock(&file_priv->fbs_lock);
        /*
         * For the non-control nodes we need to limit the list of resources
         * by IDs in the group list for this node
         */
        list_for_each(lh, &file_priv->fbs)
                fb_count++;

        /* handle this in 4 parts */
        /* FBs */
        if (card_res->count_fbs >= fb_count) {
                copied = 0;
                fb_id = (uint32_t __user *)(unsigned long)card_res->fb_id_ptr;
                list_for_each_entry(fb, &file_priv->fbs, filp_head) {
                        if (put_user(fb->base.id, fb_id + copied)) {
                                mutex_unlock(&file_priv->fbs_lock);
                                return -EFAULT;
                        }
                        copied++;
                }
        }
        card_res->count_fbs = fb_count;
        mutex_unlock(&file_priv->fbs_lock);

        drm_modeset_lock_all(dev);
        if (!drm_is_primary_client(file_priv)) {

                mode_group = NULL;
                list_for_each(lh, &dev->mode_config.crtc_list)
                        crtc_count++;

                list_for_each(lh, &dev->mode_config.connector_list)
                        connector_count++;

                list_for_each(lh, &dev->mode_config.encoder_list)
                        encoder_count++;
        } else {

                mode_group = &file_priv->master->minor->mode_group;
                crtc_count = mode_group->num_crtcs;
                connector_count = mode_group->num_connectors;
                encoder_count = mode_group->num_encoders;
        }

        card_res->max_height = dev->mode_config.max_height;
        card_res->min_height = dev->mode_config.min_height;
        card_res->max_width = dev->mode_config.max_width;
        card_res->min_width = dev->mode_config.min_width;

        /* CRTCs */
        if (card_res->count_crtcs >= crtc_count) {
                copied = 0;
                crtc_id = (uint32_t __user *)(unsigned long)card_res->crtc_id_ptr;
                if (!mode_group) {
                        list_for_each_entry(crtc, &dev->mode_config.crtc_list,
                                            head) {
                                DRM_DEBUG_KMS("[CRTC:%d]\n", crtc->base.id);
                                if (put_user(crtc->base.id, crtc_id + copied)) {
                                        ret = -EFAULT;
                                        goto out;
                                }
                                copied++;
                        }
                } else {
                        for (i = 0; i < mode_group->num_crtcs; i++) {
                                if (put_user(mode_group->id_list[i],
                                             crtc_id + copied)) {
                                        ret = -EFAULT;
                                        goto out;
                                }
                                copied++;
                        }
                }
        }
        card_res->count_crtcs = crtc_count;

        /* Encoders */
        if (card_res->count_encoders >= encoder_count) {
                copied = 0;
                encoder_id = (uint32_t __user *)(unsigned long)card_res->encoder_id_ptr;
                if (!mode_group) {
                        list_for_each_entry(encoder,
                                            &dev->mode_config.encoder_list,
                                            head) {
                                DRM_DEBUG_KMS("[ENCODER:%d:%s]\n", encoder->base.id,
                                                drm_get_encoder_name(encoder));
                                if (put_user(encoder->base.id, encoder_id +
                                             copied)) {
                                        ret = -EFAULT;
                                        goto out;
                                }
                                copied++;
                        }
                } else {
                        for (i = mode_group->num_crtcs; i < mode_group->num_crtcs + mode_group->num_encoders; i++) {
                                if (put_user(mode_group->id_list[i],
                                             encoder_id + copied)) {
                                        ret = -EFAULT;
                                        goto out;
                                }
                                copied++;
                        }

                }
        }
        card_res->count_encoders = encoder_count;

        /* Connectors */
        if (card_res->count_connectors >= connector_count) {
                copied = 0;
                connector_id = (uint32_t __user *)(unsigned long)card_res->connector_id_ptr;
                if (!mode_group) {
                        list_for_each_entry(connector,
                                            &dev->mode_config.connector_list,
                                            head) {
                                DRM_DEBUG_KMS("[CONNECTOR:%d:%s]\n",
                                        connector->base.id,
                                        drm_get_connector_name(connector));
                                if (put_user(connector->base.id,
                                             connector_id + copied)) {
                                        ret = -EFAULT;
                                        goto out;
                                }
                                copied++;
                        }
                } else {
                        int start = mode_group->num_crtcs +
                                mode_group->num_encoders;
                        for (i = start; i < start + mode_group->num_connectors; i++) {
                                if (put_user(mode_group->id_list[i],
                                             connector_id + copied)) {
                                        ret = -EFAULT;
                                        goto out;
                                }
                                copied++;
                        }
                }
        }
        card_res->count_connectors = connector_count;

        DRM_DEBUG_KMS("CRTC[%d] CONNECTORS[%d] ENCODERS[%d]\n", card_res->count_crtcs,
                  card_res->count_connectors, card_res->count_encoders);

out:
        drm_modeset_unlock_all(dev);
        return ret;
}

/**
 * drm_mode_getcrtc - get CRTC configuration
 * @dev: drm device for the ioctl
 * @data: data pointer for the ioctl
 * @file_priv: drm file for the ioctl call
 *
 * Construct a CRTC configuration structure to return to the user.
 *
 * Called by the user via ioctl.
 *
 * Returns:
 * Zero on success, errno on failure.
 */
int drm_mode_getcrtc(struct drm_device *dev,
                     void *data, struct drm_file *file_priv)
{
        struct drm_mode_crtc *crtc_resp = data;
        struct drm_crtc *crtc;
        struct drm_mode_object *obj;
        int ret = 0;

        if (!drm_core_check_feature(dev, DRIVER_MODESET))
                return -EINVAL;

        drm_modeset_lock_all(dev);

        obj = drm_mode_object_find(dev, crtc_resp->crtc_id,
                                   DRM_MODE_OBJECT_CRTC);
        if (!obj) {
                ret = -ENOENT;
                goto out;
        }
        crtc = obj_to_crtc(obj);

        crtc_resp->x = crtc->x;
        crtc_resp->y = crtc->y;
        crtc_resp->gamma_size = crtc->gamma_size;
        if (crtc->primary->fb)
                crtc_resp->fb_id = crtc->primary->fb->base.id;
        else
                crtc_resp->fb_id = 0;

        if (crtc->enabled) {

                drm_crtc_convert_to_umode(&crtc_resp->mode, &crtc->mode);
                crtc_resp->mode_valid = 1;

        } else {
                crtc_resp->mode_valid = 0;
        }

out:
        drm_modeset_unlock_all(dev);
        return ret;
}

static bool drm_mode_expose_to_userspace(const struct drm_display_mode *mode,
                                         const struct drm_file *file_priv)
{
        /*
         * If user-space hasn't configured the driver to expose the stereo 3D
         * modes, don't expose them.
         */
        if (!file_priv->stereo_allowed && drm_mode_is_stereo(mode))
                return false;

        return true;
}

/**
 * drm_mode_getconnector - get connector configuration
 * @dev: drm device for the ioctl
 * @data: data pointer for the ioctl
 * @file_priv: drm file for the ioctl call
 *
 * Construct a connector configuration structure to return to the user.
 *
 * Called by the user via ioctl.
 *
 * Returns:
 * Zero on success, errno on failure.
 */
int drm_mode_getconnector(struct drm_device *dev, void *data,
                          struct drm_file *file_priv)
{
        struct drm_mode_get_connector *out_resp = data;
        struct drm_mode_object *obj;
        struct drm_connector *connector;
        struct drm_display_mode *mode;
        int mode_count = 0;
        int props_count = 0;
        int encoders_count = 0;
        int ret = 0;
        int copied = 0;
        int i;
        struct drm_mode_modeinfo u_mode;
        struct drm_mode_modeinfo __user *mode_ptr;
        uint32_t __user *prop_ptr;
        uint64_t __user *prop_values;
        uint32_t __user *encoder_ptr;

        if (!drm_core_check_feature(dev, DRIVER_MODESET))
                return -EINVAL;

        memset(&u_mode, 0, sizeof(struct drm_mode_modeinfo));

        DRM_DEBUG_KMS("[CONNECTOR:%d:?]\n", out_resp->connector_id);

        mutex_lock(&dev->mode_config.mutex);

        obj = drm_mode_object_find(dev, out_resp->connector_id,
                                   DRM_MODE_OBJECT_CONNECTOR);
        if (!obj) {
                ret = -ENOENT;
                goto out;
        }
        connector = obj_to_connector(obj);

        props_count = connector->properties.count;

        for (i = 0; i < DRM_CONNECTOR_MAX_ENCODER; i++) {
                if (connector->encoder_ids[i] != 0) {
                        encoders_count++;
                }
        }

        if (out_resp->count_modes == 0) {
                connector->funcs->fill_modes(connector,
                                             dev->mode_config.max_width,
                                             dev->mode_config.max_height);
        }

        /* delayed so we get modes regardless of pre-fill_modes state */
        list_for_each_entry(mode, &connector->modes, head)
                if (drm_mode_expose_to_userspace(mode, file_priv))
                        mode_count++;

        out_resp->connector_id = connector->base.id;
        out_resp->connector_type = connector->connector_type;
        out_resp->connector_type_id = connector->connector_type_id;
        out_resp->mm_width = connector->display_info.width_mm;
        out_resp->mm_height = connector->display_info.height_mm;
        out_resp->subpixel = connector->display_info.subpixel_order;
        out_resp->connection = connector->status;
        if (connector->encoder)
                out_resp->encoder_id = connector->encoder->base.id;
        else
                out_resp->encoder_id = 0;

        /*
         * This ioctl is called twice, once to determine how much space is
         * needed, and the 2nd time to fill it.
         */
        if ((out_resp->count_modes >= mode_count) && mode_count) {
                copied = 0;
                mode_ptr = (struct drm_mode_modeinfo __user *)(unsigned long)out_resp->modes_ptr;
                list_for_each_entry(mode, &connector->modes, head) {
                        if (!drm_mode_expose_to_userspace(mode, file_priv))
                                continue;

                        drm_crtc_convert_to_umode(&u_mode, mode);
                        if (copy_to_user(mode_ptr + copied,
                                         &u_mode, sizeof(u_mode))) {
                                ret = -EFAULT;
                                goto out;
                        }
                        copied++;
                }
        }
        out_resp->count_modes = mode_count;

        if ((out_resp->count_props >= props_count) && props_count) {
                copied = 0;
                prop_ptr = (uint32_t __user *)(unsigned long)(out_resp->props_ptr);
                prop_values = (uint64_t __user *)(unsigned long)(out_resp->prop_values_ptr);
                for (i = 0; i < connector->properties.count; i++) {
                        if (put_user(connector->properties.ids[i],
                                     prop_ptr + copied)) {
                                ret = -EFAULT;
                                goto out;
                        }

                        if (put_user(connector->properties.values[i],
                                     prop_values + copied)) {
                                ret = -EFAULT;
                                goto out;
                        }
                        copied++;
                }
        }
        out_resp->count_props = props_count;

        if ((out_resp->count_encoders >= encoders_count) && encoders_count) {
                copied = 0;
                encoder_ptr = (uint32_t __user *)(unsigned long)(out_resp->encoders_ptr);
                for (i = 0; i < DRM_CONNECTOR_MAX_ENCODER; i++) {
                        if (connector->encoder_ids[i] != 0) {
                                if (put_user(connector->encoder_ids[i],
                                             encoder_ptr + copied)) {
                                        ret = -EFAULT;
                                        goto out;
                                }
                                copied++;
                        }
                }
        }
        out_resp->count_encoders = encoders_count;

out:
        mutex_unlock(&dev->mode_config.mutex);

        return ret;
}

/**
 * drm_mode_getencoder - get encoder configuration
 * @dev: drm device for the ioctl
 * @data: data pointer for the ioctl
 * @file_priv: drm file for the ioctl call
 *
 * Construct a encoder configuration structure to return to the user.
 *
 * Called by the user via ioctl.
 *
 * Returns:
 * Zero on success, errno on failure.
 */
int drm_mode_getencoder(struct drm_device *dev, void *data,
                        struct drm_file *file_priv)
{
        struct drm_mode_get_encoder *enc_resp = data;
        struct drm_mode_object *obj;
        struct drm_encoder *encoder;
        int ret = 0;

        if (!drm_core_check_feature(dev, DRIVER_MODESET))
                return -EINVAL;

        drm_modeset_lock_all(dev);
        obj = drm_mode_object_find(dev, enc_resp->encoder_id,
                                   DRM_MODE_OBJECT_ENCODER);
        if (!obj) {
                ret = -ENOENT;
                goto out;
        }
        encoder = obj_to_encoder(obj);

        if (encoder->crtc)
                enc_resp->crtc_id = encoder->crtc->base.id;
        else
                enc_resp->crtc_id = 0;
        enc_resp->encoder_type = encoder->encoder_type;
        enc_resp->encoder_id = encoder->base.id;
        enc_resp->possible_crtcs = encoder->possible_crtcs;
        enc_resp->possible_clones = encoder->possible_clones;

out:
        drm_modeset_unlock_all(dev);
        return ret;
}

/**
 * drm_mode_getplane_res - enumerate all plane resources
 * @dev: DRM device
 * @data: ioctl data
 * @file_priv: DRM file info
 *
 * Construct a list of plane ids to return to the user.
 *
 * Called by the user via ioctl.
 *
 * Returns:
 * Zero on success, errno on failure.
 */
int drm_mode_getplane_res(struct drm_device *dev, void *data,
                          struct drm_file *file_priv)
{
        struct drm_mode_get_plane_res *plane_resp = data;
        struct drm_mode_config *config;
        struct drm_plane *plane;
        uint32_t __user *plane_ptr;
        int copied = 0, ret = 0;
        unsigned num_planes;

        if (!drm_core_check_feature(dev, DRIVER_MODESET))
                return -EINVAL;

        drm_modeset_lock_all(dev);
        config = &dev->mode_config;

        if (file_priv->universal_planes)
                num_planes = config->num_total_plane;
        else
                num_planes = config->num_overlay_plane;

        /*
         * This ioctl is called twice, once to determine how much space is
         * needed, and the 2nd time to fill it.
         */
        if (num_planes &&
            (plane_resp->count_planes >= num_planes)) {
                plane_ptr = (uint32_t __user *)(unsigned long)plane_resp->plane_id_ptr;

                list_for_each_entry(plane, &config->plane_list, head) {
                        /*
                         * Unless userspace set the 'universal planes'
                         * capability bit, only advertise overlays.
                         */
                        if (plane->type != DRM_PLANE_TYPE_OVERLAY &&
                            !file_priv->universal_planes)
                                continue;

                        if (put_user(plane->base.id, plane_ptr + copied)) {
                                ret = -EFAULT;
                                goto out;
                        }
                        copied++;
                }
        }
        plane_resp->count_planes = num_planes;

out:
        drm_modeset_unlock_all(dev);
        return ret;
}

/**
 * drm_mode_getplane - get plane configuration
 * @dev: DRM device
 * @data: ioctl data
 * @file_priv: DRM file info
 *
 * Construct a plane configuration structure to return to the user.
 *
 * Called by the user via ioctl.
 *
 * Returns:
 * Zero on success, errno on failure.
 */
int drm_mode_getplane(struct drm_device *dev, void *data,
                      struct drm_file *file_priv)
{
        struct drm_mode_get_plane *plane_resp = data;
        struct drm_mode_object *obj;
        struct drm_plane *plane;
        uint32_t __user *format_ptr;
        int ret = 0;

        if (!drm_core_check_feature(dev, DRIVER_MODESET))
                return -EINVAL;

        drm_modeset_lock_all(dev);
        obj = drm_mode_object_find(dev, plane_resp->plane_id,
                                   DRM_MODE_OBJECT_PLANE);
        if (!obj) {
                ret = -ENOENT;
                goto out;
        }
        plane = obj_to_plane(obj);

        if (plane->crtc)
                plane_resp->crtc_id = plane->crtc->base.id;
        else
                plane_resp->crtc_id = 0;

        if (plane->fb)
                plane_resp->fb_id = plane->fb->base.id;
        else
                plane_resp->fb_id = 0;

        plane_resp->plane_id = plane->base.id;
        plane_resp->possible_crtcs = plane->possible_crtcs;
        plane_resp->gamma_size = 0;

        /*
         * This ioctl is called twice, once to determine how much space is
         * needed, and the 2nd time to fill it.
         */
        if (plane->format_count &&
            (plane_resp->count_format_types >= plane->format_count)) {
                format_ptr = (uint32_t __user *)(unsigned long)plane_resp->format_type_ptr;
                if (copy_to_user(format_ptr,
                                 plane->format_types,
                                 sizeof(uint32_t) * plane->format_count)) {
                        ret = -EFAULT;
                        goto out;
                }
        }
        plane_resp->count_format_types = plane->format_count;

out:
        drm_modeset_unlock_all(dev);
        return ret;
}

/**
 * drm_mode_setplane - configure a plane's configuration
 * @dev: DRM device
 * @data: ioctl data*
 * @file_priv: DRM file info
 *
 * Set plane configuration, including placement, fb, scaling, and other factors.
 * Or pass a NULL fb to disable.
 *
 * Returns:
 * Zero on success, errno on failure.
 */
int drm_mode_setplane(struct drm_device *dev, void *data,
                      struct drm_file *file_priv)
{
        struct drm_mode_set_plane *plane_req = data;
        struct drm_mode_object *obj;
        struct drm_plane *plane;
        struct drm_crtc *crtc;
        struct drm_framebuffer *fb = NULL, *old_fb = NULL;
        int ret = 0;
        unsigned int fb_width, fb_height;
        int i;

        if (!drm_core_check_feature(dev, DRIVER_MODESET))
                return -EINVAL;

        /*
         * First, find the plane, crtc, and fb objects.  If not available,
         * we don't bother to call the driver.
         */
        obj = drm_mode_object_find(dev, plane_req->plane_id,
                                   DRM_MODE_OBJECT_PLANE);
        if (!obj) {
                DRM_DEBUG_KMS("Unknown plane ID %d\n",
                              plane_req->plane_id);
                return -ENOENT;
        }
        plane = obj_to_plane(obj);

        /* No fb means shut it down */
        if (!plane_req->fb_id) {
                drm_modeset_lock_all(dev);
                old_fb = plane->fb;
                ret = plane->funcs->disable_plane(plane);
                if (!ret) {
                        plane->crtc = NULL;
                        plane->fb = NULL;
                } else {
                        old_fb = NULL;
                }
                drm_modeset_unlock_all(dev);
                goto out;
        }

        obj = drm_mode_object_find(dev, plane_req->crtc_id,
                                   DRM_MODE_OBJECT_CRTC);
        if (!obj) {
                DRM_DEBUG_KMS("Unknown crtc ID %d\n",
                              plane_req->crtc_id);
                ret = -ENOENT;
                goto out;
        }
        crtc = obj_to_crtc(obj);

        fb = drm_framebuffer_lookup(dev, plane_req->fb_id);
        if (!fb) {
                DRM_DEBUG_KMS("Unknown framebuffer ID %d\n",
                              plane_req->fb_id);
                ret = -ENOENT;
                goto out;
        }

        /* Check whether this plane supports the fb pixel format. */
        for (i = 0; i < plane->format_count; i++)
                if (fb->pixel_format == plane->format_types[i])
                        break;
        if (i == plane->format_count) {
                DRM_DEBUG_KMS("Invalid pixel format %s\n",
                              drm_get_format_name(fb->pixel_format));
                ret = -EINVAL;
                goto out;
        }

        fb_width = fb->width << 16;
        fb_height = fb->height << 16;

        /* Make sure source coordinates are inside the fb. */
        if (plane_req->src_w > fb_width ||
            plane_req->src_x > fb_width - plane_req->src_w ||
            plane_req->src_h > fb_height ||
            plane_req->src_y > fb_height - plane_req->src_h) {
                DRM_DEBUG_KMS("Invalid source coordinates "
                              "%u.%06ux%u.%06u+%u.%06u+%u.%06u\n",
                              plane_req->src_w >> 16,
                              ((plane_req->src_w & 0xffff) * 15625) >> 10,
                              plane_req->src_h >> 16,
                              ((plane_req->src_h & 0xffff) * 15625) >> 10,
                              plane_req->src_x >> 16,
                              ((plane_req->src_x & 0xffff) * 15625) >> 10,
                              plane_req->src_y >> 16,
                              ((plane_req->src_y & 0xffff) * 15625) >> 10);
                ret = -ENOSPC;
                goto out;
        }

        /* Give drivers some help against integer overflows */
        if (plane_req->crtc_w > INT_MAX ||
            plane_req->crtc_x > INT_MAX - (int32_t) plane_req->crtc_w ||
            plane_req->crtc_h > INT_MAX ||
            plane_req->crtc_y > INT_MAX - (int32_t) plane_req->crtc_h) {
                DRM_DEBUG_KMS("Invalid CRTC coordinates %ux%u+%d+%d\n",
                              plane_req->crtc_w, plane_req->crtc_h,
                              plane_req->crtc_x, plane_req->crtc_y);
                ret = -ERANGE;
                goto out;
        }

        drm_modeset_lock_all(dev);
        old_fb = plane->fb;
        ret = plane->funcs->update_plane(plane, crtc, fb,
                                         plane_req->crtc_x, plane_req->crtc_y,
                                         plane_req->crtc_w, plane_req->crtc_h,
                                         plane_req->src_x, plane_req->src_y,
                                         plane_req->src_w, plane_req->src_h);
        if (!ret) {
                plane->crtc = crtc;
                plane->fb = fb;
                fb = NULL;
        } else {
                old_fb = NULL;
        }
        drm_modeset_unlock_all(dev);

out:
        if (fb)
                drm_framebuffer_unreference(fb);
        if (old_fb)
                drm_framebuffer_unreference(old_fb);

        return ret;
}

/**
 * drm_mode_set_config_internal - helper to call ->set_config
 * @set: modeset config to set
 *
 * This is a little helper to wrap internal calls to the ->set_config driver
 * interface. The only thing it adds is correct refcounting dance.
 * 
 * Returns:
 * Zero on success, errno on failure.
 */
int drm_mode_set_config_internal(struct drm_mode_set *set)
{
        struct drm_crtc *crtc = set->crtc;
        struct drm_framebuffer *fb;
        struct drm_crtc *tmp;
        int ret;

        /*
         * NOTE: ->set_config can also disable other crtcs (if we steal all
         * connectors from it), hence we need to refcount the fbs across all
         * crtcs. Atomic modeset will have saner semantics ...
         */
        list_for_each_entry(tmp, &crtc->dev->mode_config.crtc_list, head)
                tmp->old_fb = tmp->primary->fb;

        fb = set->fb;

        ret = crtc->funcs->set_config(set);
        if (ret == 0) {
                crtc->primary->crtc = crtc;
                crtc->primary->fb = fb;
        }

        list_for_each_entry(tmp, &crtc->dev->mode_config.crtc_list, head) {
                if (tmp->primary->fb)
                        drm_framebuffer_reference(tmp->primary->fb);
                if (tmp->old_fb)
                        drm_framebuffer_unreference(tmp->old_fb);
        }

        return ret;
}
EXPORT_SYMBOL(drm_mode_set_config_internal);

/**
 * drm_crtc_check_viewport - Checks that a framebuffer is big enough for the
 *     CRTC viewport
 * @crtc: CRTC that framebuffer will be displayed on
 * @x: x panning
 * @y: y panning
 * @mode: mode that framebuffer will be displayed under
 * @fb: framebuffer to check size of
 */
int drm_crtc_check_viewport(const struct drm_crtc *crtc,
                            int x, int y,
                            const struct drm_display_mode *mode,
                            const struct drm_framebuffer *fb)

{
        int hdisplay, vdisplay;

        hdisplay = mode->hdisplay;
        vdisplay = mode->vdisplay;

        if (drm_mode_is_stereo(mode)) {
                struct drm_display_mode adjusted = *mode;

                drm_mode_set_crtcinfo(&adjusted, CRTC_STEREO_DOUBLE);
                hdisplay = adjusted.crtc_hdisplay;
                vdisplay = adjusted.crtc_vdisplay;
        }

        if (crtc->invert_dimensions)
                swap(hdisplay, vdisplay);

        if (hdisplay > fb->width ||
            vdisplay > fb->height ||
            x > fb->width - hdisplay ||
            y > fb->height - vdisplay) {
                DRM_DEBUG_KMS("Invalid fb size %ux%u for CRTC viewport %ux%u+%d+%d%s.\n",
                              fb->width, fb->height, hdisplay, vdisplay, x, y,
                              crtc->invert_dimensions ? " (inverted)" : "");
                return -ENOSPC;
        }

        return 0;
}
EXPORT_SYMBOL(drm_crtc_check_viewport);

/**
 * drm_mode_setcrtc - set CRTC configuration
 * @dev: drm device for the ioctl
 * @data: data pointer for the ioctl
 * @file_priv: drm file for the ioctl call
 *
 * Build a new CRTC configuration based on user request.
 *
 * Called by the user via ioctl.
 *
 * Returns:
 * Zero on success, errno on failure.
 */
int drm_mode_setcrtc(struct drm_device *dev, void *data,
                     struct drm_file *file_priv)
{
        struct drm_mode_config *config = &dev->mode_config;
        struct drm_mode_crtc *crtc_req = data;
        struct drm_mode_object *obj;
        struct drm_crtc *crtc;
        struct drm_connector **connector_set = NULL, *connector;
        struct drm_framebuffer *fb = NULL;
        struct drm_display_mode *mode = NULL;
        struct drm_mode_set set;
        uint32_t __user *set_connectors_ptr;
        int ret;
        int i;

        if (!drm_core_check_feature(dev, DRIVER_MODESET))
                return -EINVAL;

        /* For some reason crtc x/y offsets are signed internally. */
        if (crtc_req->x > INT_MAX || crtc_req->y > INT_MAX)
                return -ERANGE;

        drm_modeset_lock_all(dev);
        obj = drm_mode_object_find(dev, crtc_req->crtc_id,
                                   DRM_MODE_OBJECT_CRTC);
        if (!obj) {
                DRM_DEBUG_KMS("Unknown CRTC ID %d\n", crtc_req->crtc_id);
                ret = -ENOENT;
                goto out;
        }
        crtc = obj_to_crtc(obj);
        DRM_DEBUG_KMS("[CRTC:%d]\n", crtc->base.id);

        if (crtc_req->mode_valid) {
                /* If we have a mode we need a framebuffer. */
                /* If we pass -1, set the mode with the currently bound fb */
                if (crtc_req->fb_id == -1) {
                        if (!crtc->primary->fb) {
                                DRM_DEBUG_KMS("CRTC doesn't have current FB\n");
                                ret = -EINVAL;
                                goto out;
                        }
                        fb = crtc->primary->fb;
                        /* Make refcounting symmetric with the lookup path. */
                        drm_framebuffer_reference(fb);
                } else {
                        fb = drm_framebuffer_lookup(dev, crtc_req->fb_id);
                        if (!fb) {
                                DRM_DEBUG_KMS("Unknown FB ID%d\n",
                                                crtc_req->fb_id);
                                ret = -ENOENT;
                                goto out;
                        }
                }

                mode = drm_mode_create(dev);
                if (!mode) {
                        ret = -ENOMEM;
                        goto out;
                }

                ret = drm_crtc_convert_umode(mode, &crtc_req->mode);
                if (ret) {
                        DRM_DEBUG_KMS("Invalid mode\n");
                        goto out;
                }

                drm_mode_set_crtcinfo(mode, CRTC_INTERLACE_HALVE_V);

                ret = drm_crtc_check_viewport(crtc, crtc_req->x, crtc_req->y,
                                              mode, fb);
                if (ret)
                        goto out;

        }

        if (crtc_req->count_connectors == 0 && mode) {
                DRM_DEBUG_KMS("Count connectors is 0 but mode set\n");
                ret = -EINVAL;
                goto out;
        }

        if (crtc_req->count_connectors > 0 && (!mode || !fb)) {
                DRM_DEBUG_KMS("Count connectors is %d but no mode or fb set\n",
                          crtc_req->count_connectors);
                ret = -EINVAL;
                goto out;
        }

        if (crtc_req->count_connectors > 0) {
                u32 out_id;

                /* Avoid unbounded kernel memory allocation */
                if (crtc_req->count_connectors > config->num_connector) {
                        ret = -EINVAL;
                        goto out;
                }

                connector_set = kmalloc(crtc_req->count_connectors *
                                        sizeof(struct drm_connector *),
                                        GFP_KERNEL);
                if (!connector_set) {
                        ret = -ENOMEM;
                        goto out;
                }

                for (i = 0; i < crtc_req->count_connectors; i++) {
                        set_connectors_ptr = (uint32_t __user *)(unsigned long)crtc_req->set_connectors_ptr;
                        if (get_user(out_id, &set_connectors_ptr[i])) {
                                ret = -EFAULT;
                                goto out;
                        }

                        obj = drm_mode_object_find(dev, out_id,
                                                   DRM_MODE_OBJECT_CONNECTOR);
                        if (!obj) {
                                DRM_DEBUG_KMS("Connector id %d unknown\n",
                                                out_id);
                                ret = -ENOENT;
                                goto out;
                        }
                        connector = obj_to_connector(obj);
                        DRM_DEBUG_KMS("[CONNECTOR:%d:%s]\n",
                                        connector->base.id,
                                        drm_get_connector_name(connector));

                        connector_set[i] = connector;
                }
        }

        set.crtc = crtc;
        set.x = crtc_req->x;
        set.y = crtc_req->y;
        set.mode = mode;
        set.connectors = connector_set;
        set.num_connectors = crtc_req->count_connectors;
        set.fb = fb;
        ret = drm_mode_set_config_internal(&set);

out:
        if (fb)
                drm_framebuffer_unreference(fb);

        kfree(connector_set);
        drm_mode_destroy(dev, mode);
        drm_modeset_unlock_all(dev);
        return ret;
}

static int drm_mode_cursor_common(struct drm_device *dev,
                                  struct drm_mode_cursor2 *req,
                                  struct drm_file *file_priv)
{
        struct drm_mode_object *obj;
        struct drm_crtc *crtc;
        int ret = 0;

        if (!drm_core_check_feature(dev, DRIVER_MODESET))
                return -EINVAL;

        if (!req->flags || (~DRM_MODE_CURSOR_FLAGS & req->flags))
                return -EINVAL;

        obj = drm_mode_object_find(dev, req->crtc_id, DRM_MODE_OBJECT_CRTC);
        if (!obj) {
                DRM_DEBUG_KMS("Unknown CRTC ID %d\n", req->crtc_id);
                return -ENOENT;
        }
        crtc = obj_to_crtc(obj);

        mutex_lock(&crtc->mutex);
        if (req->flags & DRM_MODE_CURSOR_BO) {
                if (!crtc->funcs->cursor_set && !crtc->funcs->cursor_set2) {
                        ret = -ENXIO;
                        goto out;
                }
                /* Turns off the cursor if handle is 0 */
                if (crtc->funcs->cursor_set2)
                        ret = crtc->funcs->cursor_set2(crtc, file_priv, req->handle,
                                                      req->width, req->height, req->hot_x, req->hot_y);
                else
                        ret = crtc->funcs->cursor_set(crtc, file_priv, req->handle,
                                                      req->width, req->height);
        }

        if (req->flags & DRM_MODE_CURSOR_MOVE) {
                if (crtc->funcs->cursor_move) {
                        ret = crtc->funcs->cursor_move(crtc, req->x, req->y);
                } else {
                        ret = -EFAULT;
                        goto out;
                }
        }
out:
        mutex_unlock(&crtc->mutex);

        return ret;

}


/**
 * drm_mode_cursor_ioctl - set CRTC's cursor configuration
 * @dev: drm device for the ioctl
 * @data: data pointer for the ioctl
 * @file_priv: drm file for the ioctl call
 *
 * Set the cursor configuration based on user request.
 *
 * Called by the user via ioctl.
 *
 * Returns:
 * Zero on success, errno on failure.
 */
int drm_mode_cursor_ioctl(struct drm_device *dev,
                          void *data, struct drm_file *file_priv)
{
        struct drm_mode_cursor *req = data;
        struct drm_mode_cursor2 new_req;

        memcpy(&new_req, req, sizeof(struct drm_mode_cursor));
        new_req.hot_x = new_req.hot_y = 0;

        return drm_mode_cursor_common(dev, &new_req, file_priv);
}

/**
 * drm_mode_cursor2_ioctl - set CRTC's cursor configuration
 * @dev: drm device for the ioctl
 * @data: data pointer for the ioctl
 * @file_priv: drm file for the ioctl call
 *
 * Set the cursor configuration based on user request. This implements the 2nd
 * version of the cursor ioctl, which allows userspace to additionally specify
 * the hotspot of the pointer.
 *
 * Called by the user via ioctl.
 *
 * Returns:
 * Zero on success, errno on failure.
 */
int drm_mode_cursor2_ioctl(struct drm_device *dev,
                           void *data, struct drm_file *file_priv)
{
        struct drm_mode_cursor2 *req = data;
        return drm_mode_cursor_common(dev, req, file_priv);
}

/**
 * drm_mode_legacy_fb_format - compute drm fourcc code from legacy description
 * @bpp: bits per pixels
 * @depth: bit depth per pixel
 *
 * Computes a drm fourcc pixel format code for the given @bpp/@depth values.
 * Useful in fbdev emulation code, since that deals in those values.
 */
uint32_t drm_mode_legacy_fb_format(uint32_t bpp, uint32_t depth)
{
        uint32_t fmt;

        switch (bpp) {
        case 8:
                fmt = DRM_FORMAT_C8;
                break;
        case 16:
                if (depth == 15)
                        fmt = DRM_FORMAT_XRGB1555;
                else
                        fmt = DRM_FORMAT_RGB565;
                break;
        case 24:
                fmt = DRM_FORMAT_RGB888;
                break;
        case 32:
                if (depth == 24)
                        fmt = DRM_FORMAT_XRGB8888;
                else if (depth == 30)
                        fmt = DRM_FORMAT_XRGB2101010;
                else
                        fmt = DRM_FORMAT_ARGB8888;
                break;
        default:
                DRM_ERROR("bad bpp, assuming x8r8g8b8 pixel format\n");
                fmt = DRM_FORMAT_XRGB8888;
                break;
        }

        return fmt;
}
EXPORT_SYMBOL(drm_mode_legacy_fb_format);

/**
 * drm_mode_addfb - add an FB to the graphics configuration
 * @dev: drm device for the ioctl
 * @data: data pointer for the ioctl
 * @file_priv: drm file for the ioctl call
 *
 * Add a new FB to the specified CRTC, given a user request. This is the
 * original addfb ioclt which only supported RGB formats.
 *
 * Called by the user via ioctl.
 *
 * Returns:
 * Zero on success, errno on failure.
 */
int drm_mode_addfb(struct drm_device *dev,
                   void *data, struct drm_file *file_priv)
{
        struct drm_mode_fb_cmd *or = data;
        struct drm_mode_fb_cmd2 r = {};
        struct drm_mode_config *config = &dev->mode_config;
        struct drm_framebuffer *fb;
        int ret = 0;

        /* Use new struct with format internally */
        r.fb_id = or->fb_id;
        r.width = or->width;
        r.height = or->height;
        r.pitches[0] = or->pitch;
        r.pixel_format = drm_mode_legacy_fb_format(or->bpp, or->depth);
        r.handles[0] = or->handle;

        if (!drm_core_check_feature(dev, DRIVER_MODESET))
                return -EINVAL;

        if ((config->min_width > r.width) || (r.width > config->max_width))
                return -EINVAL;

        if ((config->min_height > r.height) || (r.height > config->max_height))
                return -EINVAL;

        fb = dev->mode_config.funcs->fb_create(dev, file_priv, &r);
        if (IS_ERR(fb)) {
                DRM_DEBUG_KMS("could not create framebuffer\n");
                return PTR_ERR(fb);
        }

        mutex_lock(&file_priv->fbs_lock);
        or->fb_id = fb->base.id;
        list_add(&fb->filp_head, &file_priv->fbs);
        DRM_DEBUG_KMS("[FB:%d]\n", fb->base.id);
        mutex_unlock(&file_priv->fbs_lock);

        return ret;
}

static int format_check(const struct drm_mode_fb_cmd2 *r)
{
        uint32_t format = r->pixel_format & ~DRM_FORMAT_BIG_ENDIAN;

        switch (format) {
        case DRM_FORMAT_C8:
        case DRM_FORMAT_RGB332:
        case DRM_FORMAT_BGR233:
        case DRM_FORMAT_XRGB4444:
        case DRM_FORMAT_XBGR4444:
        case DRM_FORMAT_RGBX4444:
        case DRM_FORMAT_BGRX4444:
        case DRM_FORMAT_ARGB4444:
        case DRM_FORMAT_ABGR4444:
        case DRM_FORMAT_RGBA4444:
        case DRM_FORMAT_BGRA4444:
        case DRM_FORMAT_XRGB1555:
        case DRM_FORMAT_XBGR1555:
        case DRM_FORMAT_RGBX5551:
        case DRM_FORMAT_BGRX5551:
        case DRM_FORMAT_ARGB1555:
        case DRM_FORMAT_ABGR1555:
        case DRM_FORMAT_RGBA5551:
        case DRM_FORMAT_BGRA5551:
        case DRM_FORMAT_RGB565:
        case DRM_FORMAT_BGR565:
        case DRM_FORMAT_RGB888:
        case DRM_FORMAT_BGR888:
        case DRM_FORMAT_XRGB8888:
        case DRM_FORMAT_XBGR8888:
        case DRM_FORMAT_RGBX8888:
        case DRM_FORMAT_BGRX8888:
        case DRM_FORMAT_ARGB8888:
        case DRM_FORMAT_ABGR8888:
        case DRM_FORMAT_RGBA8888:
        case DRM_FORMAT_BGRA8888:
        case DRM_FORMAT_XRGB2101010:
        case DRM_FORMAT_XBGR2101010:
        case DRM_FORMAT_RGBX1010102:
        case DRM_FORMAT_BGRX1010102:
        case DRM_FORMAT_ARGB2101010:
        case DRM_FORMAT_ABGR2101010:
        case DRM_FORMAT_RGBA1010102:
        case DRM_FORMAT_BGRA1010102:
        case DRM_FORMAT_YUYV:
        case DRM_FORMAT_YVYU:
        case DRM_FORMAT_UYVY:
        case DRM_FORMAT_VYUY:
        case DRM_FORMAT_AYUV:
        case DRM_FORMAT_NV12:
        case DRM_FORMAT_NV21:
        case DRM_FORMAT_NV16:
        case DRM_FORMAT_NV61:
        case DRM_FORMAT_NV24:
        case DRM_FORMAT_NV42:
        case DRM_FORMAT_YUV410:
        case DRM_FORMAT_YVU410:
        case DRM_FORMAT_YUV411:
        case DRM_FORMAT_YVU411:
        case DRM_FORMAT_YUV420:
        case DRM_FORMAT_YVU420:
        case DRM_FORMAT_YUV422:
        case DRM_FORMAT_YVU422:
        case DRM_FORMAT_YUV444:
        case DRM_FORMAT_YVU444:
                return 0;
        default:
                DRM_DEBUG_KMS("invalid pixel format %s\n",
                              drm_get_format_name(r->pixel_format));
                return -EINVAL;
        }
}

static int framebuffer_check(const struct drm_mode_fb_cmd2 *r)
{
        int ret, hsub, vsub, num_planes, i;

        ret = format_check(r);
        if (ret) {
                DRM_DEBUG_KMS("bad framebuffer format %s\n",
                              drm_get_format_name(r->pixel_format));
                return ret;
        }

        hsub = drm_format_horz_chroma_subsampling(r->pixel_format);
        vsub = drm_format_vert_chroma_subsampling(r->pixel_format);
        num_planes = drm_format_num_planes(r->pixel_format);

        if (r->width == 0 || r->width % hsub) {
                DRM_DEBUG_KMS("bad framebuffer width %u\n", r->height);
                return -EINVAL;
        }

        if (r->height == 0 || r->height % vsub) {
                DRM_DEBUG_KMS("bad framebuffer height %u\n", r->height);
                return -EINVAL;
        }

        for (i = 0; i < num_planes; i++) {
                unsigned int width = r->width / (i != 0 ? hsub : 1);
                unsigned int height = r->height / (i != 0 ? vsub : 1);
                unsigned int cpp = drm_format_plane_cpp(r->pixel_format, i);

                if (!r->handles[i]) {
                        DRM_DEBUG_KMS("no buffer object handle for plane %d\n", i);
                        return -EINVAL;
                }

                if ((uint64_t) width * cpp > UINT_MAX)
                        return -ERANGE;

                if ((uint64_t) height * r->pitches[i] + r->offsets[i] > UINT_MAX)
                        return -ERANGE;

                if (r->pitches[i] < width * cpp) {
                        DRM_DEBUG_KMS("bad pitch %u for plane %d\n", r->pitches[i], i);
                        return -EINVAL;
                }
        }

        return 0;
}

/**
 * drm_mode_addfb2 - add an FB to the graphics configuration
 * @dev: drm device for the ioctl
 * @data: data pointer for the ioctl
 * @file_priv: drm file for the ioctl call
 *
 * Add a new FB to the specified CRTC, given a user request with format. This is
 * the 2nd version of the addfb ioctl, which supports multi-planar framebuffers
 * and uses fourcc codes as pixel format specifiers.
 *
 * Called by the user via ioctl.
 *
 * Returns:
 * Zero on success, errno on failure.
 */
int drm_mode_addfb2(struct drm_device *dev,
                    void *data, struct drm_file *file_priv)
{
        struct drm_mode_fb_cmd2 *r = data;
        struct drm_mode_config *config = &dev->mode_config;
        struct drm_framebuffer *fb;
        int ret;

        if (!drm_core_check_feature(dev, DRIVER_MODESET))
                return -EINVAL;

        if (r->flags & ~DRM_MODE_FB_INTERLACED) {
                DRM_DEBUG_KMS("bad framebuffer flags 0x%08x\n", r->flags);
                return -EINVAL;
        }

        if ((config->min_width > r->width) || (r->width > config->max_width)) {
                DRM_DEBUG_KMS("bad framebuffer width %d, should be >= %d && <= %d\n",
                          r->width, config->min_width, config->max_width);
                return -EINVAL;
        }
        if ((config->min_height > r->height) || (r->height > config->max_height)) {
                DRM_DEBUG_KMS("bad framebuffer height %d, should be >= %d && <= %d\n",
                          r->height, config->min_height, config->max_height);
                return -EINVAL;
        }

        ret = framebuffer_check(r);
        if (ret)
                return ret;

        fb = dev->mode_config.funcs->fb_create(dev, file_priv, r);
        if (IS_ERR(fb)) {
                DRM_DEBUG_KMS("could not create framebuffer\n");
                return PTR_ERR(fb);
        }

        mutex_lock(&file_priv->fbs_lock);
        r->fb_id = fb->base.id;
        list_add(&fb->filp_head, &file_priv->fbs);
        DRM_DEBUG_KMS("[FB:%d]\n", fb->base.id);
        mutex_unlock(&file_priv->fbs_lock);


        return ret;
}

/**
 * drm_mode_rmfb - remove an FB from the configuration
 * @dev: drm device for the ioctl
 * @data: data pointer for the ioctl
 * @file_priv: drm file for the ioctl call
 *
 * Remove the FB specified by the user.
 *
 * Called by the user via ioctl.
 *
 * Returns:
 * Zero on success, errno on failure.
 */
int drm_mode_rmfb(struct drm_device *dev,
                   void *data, struct drm_file *file_priv)
{
        struct drm_framebuffer *fb = NULL;
        struct drm_framebuffer *fbl = NULL;
        uint32_t *id = data;
        int found = 0;

        if (!drm_core_check_feature(dev, DRIVER_MODESET))
                return -EINVAL;

        mutex_lock(&file_priv->fbs_lock);
        mutex_lock(&dev->mode_config.fb_lock);
        fb = __drm_framebuffer_lookup(dev, *id);
        if (!fb)
                goto fail_lookup;

        list_for_each_entry(fbl, &file_priv->fbs, filp_head)
                if (fb == fbl)
                        found = 1;
        if (!found)
                goto fail_lookup;

        /* Mark fb as reaped, we still have a ref from fpriv->fbs. */
        __drm_framebuffer_unregister(dev, fb);

        list_del_init(&fb->filp_head);
        mutex_unlock(&dev->mode_config.fb_lock);
        mutex_unlock(&file_priv->fbs_lock);

        drm_framebuffer_remove(fb);

        return 0;

fail_lookup:
        mutex_unlock(&dev->mode_config.fb_lock);
        mutex_unlock(&file_priv->fbs_lock);

        return -ENOENT;
}

/**
 * drm_mode_getfb - get FB info
 * @dev: drm device for the ioctl
 * @data: data pointer for the ioctl
 * @file_priv: drm file for the ioctl call
 *
 * Lookup the FB given its ID and return info about it.
 *
 * Called by the user via ioctl.
 *
 * Returns:
 * Zero on success, errno on failure.
 */
int drm_mode_getfb(struct drm_device *dev,
                   void *data, struct drm_file *file_priv)
{
        struct drm_mode_fb_cmd *r = data;
        struct drm_framebuffer *fb;
        int ret;

        if (!drm_core_check_feature(dev, DRIVER_MODESET))
                return -EINVAL;

        fb = drm_framebuffer_lookup(dev, r->fb_id);
        if (!fb)
                return -ENOENT;

        r->height = fb->height;
        r->width = fb->width;
        r->depth = fb->depth;
        r->bpp = fb->bits_per_pixel;
        r->pitch = fb->pitches[0];
        if (fb->funcs->create_handle) {
                if (file_priv->is_master || capable(CAP_SYS_ADMIN) ||
                    drm_is_control_client(file_priv)) {
                        ret = fb->funcs->create_handle(fb, file_priv,
                                                       &r->handle);
                } else {
                        /* GET_FB() is an unprivileged ioctl so we must not
                         * return a buffer-handle to non-master processes! For
                         * backwards-compatibility reasons, we cannot make
                         * GET_FB() privileged, so just return an invalid handle
                         * for non-masters. */
                        r->handle = 0;
                        ret = 0;
                }
        } else {
                ret = -ENODEV;
        }

        drm_framebuffer_unreference(fb);

        return ret;
}

/**
 * drm_mode_dirtyfb_ioctl - flush frontbuffer rendering on an FB
 * @dev: drm device for the ioctl
 * @data: data pointer for the ioctl
 * @file_priv: drm file for the ioctl call
 *
 * Lookup the FB and flush out the damaged area supplied by userspace as a clip
 * rectangle list. Generic userspace which does frontbuffer rendering must call
 * this ioctl to flush out the changes on manual-update display outputs, e.g.
 * usb display-link, mipi manual update panels or edp panel self refresh modes.
 *
 * Modesetting drivers which always update the frontbuffer do not need to
 * implement the corresponding ->dirty framebuffer callback.
 *
 * Called by the user via ioctl.
 *
 * Returns:
 * Zero on success, errno on failure.
 */
int drm_mode_dirtyfb_ioctl(struct drm_device *dev,
                           void *data, struct drm_file *file_priv)
{
        struct drm_clip_rect __user *clips_ptr;
        struct drm_clip_rect *clips = NULL;
        struct drm_mode_fb_dirty_cmd *r = data;
        struct drm_framebuffer *fb;
        unsigned flags;
        int num_clips;
        int ret;

        if (!drm_core_check_feature(dev, DRIVER_MODESET))
                return -EINVAL;

        fb = drm_framebuffer_lookup(dev, r->fb_id);
        if (!fb)
                return -ENOENT;

        num_clips = r->num_clips;
        clips_ptr = (struct drm_clip_rect __user *)(unsigned long)r->clips_ptr;

        if (!num_clips != !clips_ptr) {
                ret = -EINVAL;
                goto out_err1;
        }

        flags = DRM_MODE_FB_DIRTY_FLAGS & r->flags;

        /* If userspace annotates copy, clips must come in pairs */
        if (flags & DRM_MODE_FB_DIRTY_ANNOTATE_COPY && (num_clips % 2)) {
                ret = -EINVAL;
                goto out_err1;
        }

        if (num_clips && clips_ptr) {
                if (num_clips < 0 || num_clips > DRM_MODE_FB_DIRTY_MAX_CLIPS) {
                        ret = -EINVAL;
                        goto out_err1;
                }
                clips = kzalloc(num_clips * sizeof(*clips), GFP_KERNEL);
                if (!clips) {
                        ret = -ENOMEM;
                        goto out_err1;
                }

                ret = copy_from_user(clips, clips_ptr,
                                     num_clips * sizeof(*clips));
                if (ret) {
                        ret = -EFAULT;
                        goto out_err2;
                }
        }

        if (fb->funcs->dirty) {
                ret = fb->funcs->dirty(fb, file_priv, flags, r->color,
                                       clips, num_clips);
        } else {
                ret = -ENOSYS;
        }

out_err2:
        kfree(clips);
out_err1:
        drm_framebuffer_unreference(fb);

        return ret;
}


/**
 * drm_fb_release - remove and free the FBs on this file
 * @priv: drm file for the ioctl
 *
 * Destroy all the FBs associated with @filp.
 *
 * Called by the user via ioctl.
 *
 * Returns:
 * Zero on success, errno on failure.
 */
void drm_fb_release(struct drm_file *priv)
{
        struct drm_device *dev = priv->minor->dev;
        struct drm_framebuffer *fb, *tfb;

        mutex_lock(&priv->fbs_lock);
        list_for_each_entry_safe(fb, tfb, &priv->fbs, filp_head) {

                mutex_lock(&dev->mode_config.fb_lock);
                /* Mark fb as reaped, we still have a ref from fpriv->fbs. */
                __drm_framebuffer_unregister(dev, fb);
                mutex_unlock(&dev->mode_config.fb_lock);

                list_del_init(&fb->filp_head);

                /* This will also drop the fpriv->fbs reference. */
                drm_framebuffer_remove(fb);
        }
        mutex_unlock(&priv->fbs_lock);
}

/**
 * drm_property_create - create a new property type
 * @dev: drm device
 * @flags: flags specifying the property type
 * @name: name of the property
 * @num_values: number of pre-defined values
 *
 * This creates a new generic drm property which can then be attached to a drm
 * object with drm_object_attach_property. The returned property object must be
 * freed with drm_property_destroy.
 *
 * Returns:
 * A pointer to the newly created property on success, NULL on failure.
 */
struct drm_property *drm_property_create(struct drm_device *dev, int flags,
                                         const char *name, int num_values)
{
        struct drm_property *property = NULL;
        int ret;

        property = kzalloc(sizeof(struct drm_property), GFP_KERNEL);
        if (!property)
                return NULL;

        if (num_values) {
                property->values = kzalloc(sizeof(uint64_t)*num_values, GFP_KERNEL);
                if (!property->values)
                        goto fail;
        }

        ret = drm_mode_object_get(dev, &property->base, DRM_MODE_OBJECT_PROPERTY);
        if (ret)
                goto fail;

        property->flags = flags;
        property->num_values = num_values;
        INIT_LIST_HEAD(&property->enum_blob_list);

        if (name) {
                strncpy(property->name, name, DRM_PROP_NAME_LEN);
                property->name[DRM_PROP_NAME_LEN-1] = '\0';
        }

        list_add_tail(&property->head, &dev->mode_config.property_list);
        return property;
fail:
        kfree(property->values);
        kfree(property);
        return NULL;
}
EXPORT_SYMBOL(drm_property_create);

/**
 * drm_property_create - create a new enumeration property type
 * @dev: drm device
 * @flags: flags specifying the property type
 * @name: name of the property
 * @props: enumeration lists with property values
 * @num_values: number of pre-defined values
 *
 * This creates a new generic drm property which can then be attached to a drm
 * object with drm_object_attach_property. The returned property object must be
 * freed with drm_property_destroy.
 *
 * Userspace is only allowed to set one of the predefined values for enumeration
 * properties.
 *
 * Returns:
 * A pointer to the newly created property on success, NULL on failure.
 */
struct drm_property *drm_property_create_enum(struct drm_device *dev, int flags,
                                         const char *name,
                                         const struct drm_prop_enum_list *props,
                                         int num_values)
{
        struct drm_property *property;
        int i, ret;

        flags |= DRM_MODE_PROP_ENUM;

        property = drm_property_create(dev, flags, name, num_values);
        if (!property)
                return NULL;

        for (i = 0; i < num_values; i++) {
                ret = drm_property_add_enum(property, i,
                                      props[i].type,
                                      props[i].name);
                if (ret) {
                        drm_property_destroy(dev, property);
                        return NULL;
                }
        }

        return property;
}
EXPORT_SYMBOL(drm_property_create_enum);

/**
 * drm_property_create - create a new bitmask property type
 * @dev: drm device
 * @flags: flags specifying the property type
 * @name: name of the property
 * @props: enumeration lists with property bitflags
 * @num_values: number of pre-defined values
 *
 * This creates a new generic drm property which can then be attached to a drm
 * object with drm_object_attach_property. The returned property object must be
 * freed with drm_property_destroy.
 *
 * Compared to plain enumeration properties userspace is allowed to set any
 * or'ed together combination of the predefined property bitflag values
 *
 * Returns:
 * A pointer to the newly created property on success, NULL on failure.
 */
struct drm_property *drm_property_create_bitmask(struct drm_device *dev,
                                         int flags, const char *name,
                                         const struct drm_prop_enum_list *props,
                                         int num_values)
{
        struct drm_property *property;
        int i, ret;

        flags |= DRM_MODE_PROP_BITMASK;

        property = drm_property_create(dev, flags, name, num_values);
        if (!property)
                return NULL;

        for (i = 0; i < num_values; i++) {
                ret = drm_property_add_enum(property, i,
                                      props[i].type,
                                      props[i].name);
                if (ret) {
                        drm_property_destroy(dev, property);
                        return NULL;
                }
        }

        return property;
}
EXPORT_SYMBOL(drm_property_create_bitmask);

/**
 * drm_property_create - create a new ranged property type
 * @dev: drm device
 * @flags: flags specifying the property type
 * @name: name of the property
 * @min: minimum value of the property
 * @max: maximum value of the property
 *
 * This creates a new generic drm property which can then be attached to a drm
 * object with drm_object_attach_property. The returned property object must be
 * freed with drm_property_destroy.
 *
 * Userspace is allowed to set any interger value in the (min, max) range
 * inclusive.
 *
 * Returns:
 * A pointer to the newly created property on success, NULL on failure.
 */
struct drm_property *drm_property_create_range(struct drm_device *dev, int flags,
                                         const char *name,
                                         uint64_t min, uint64_t max)
{
        struct drm_property *property;

        flags |= DRM_MODE_PROP_RANGE;

        property = drm_property_create(dev, flags, name, 2);
        if (!property)
                return NULL;

        property->values[0] = min;
        property->values[1] = max;

        return property;
}
EXPORT_SYMBOL(drm_property_create_range);

/**
 * drm_property_add_enum - add a possible value to an enumeration property
 * @property: enumeration property to change
 * @index: index of the new enumeration
 * @value: value of the new enumeration
 * @name: symbolic name of the new enumeration
 *
 * This functions adds enumerations to a property.
 *
 * It's use is deprecated, drivers should use one of the more specific helpers
 * to directly create the property with all enumerations already attached.
 *
 * Returns:
 * Zero on success, error code on failure.
 */
int drm_property_add_enum(struct drm_property *property, int index,
                          uint64_t value, const char *name)
{
        struct drm_property_enum *prop_enum;

        if (!(property->flags & (DRM_MODE_PROP_ENUM | DRM_MODE_PROP_BITMASK)))
                return -EINVAL;

        /*
         * Bitmask enum properties have the additional constraint of values
         * from 0 to 63
         */
        if ((property->flags & DRM_MODE_PROP_BITMASK) && (value > 63))
                return -EINVAL;

        if (!list_empty(&property->enum_blob_list)) {
                list_for_each_entry(prop_enum, &property->enum_blob_list, head) {
                        if (prop_enum->value == value) {
                                strncpy(prop_enum->name, name, DRM_PROP_NAME_LEN);
                                prop_enum->name[DRM_PROP_NAME_LEN-1] = '\0';
                                return 0;
                        }
                }
        }

        prop_enum = kzalloc(sizeof(struct drm_property_enum), GFP_KERNEL);
        if (!prop_enum)
                return -ENOMEM;

        strncpy(prop_enum->name, name, DRM_PROP_NAME_LEN);
        prop_enum->name[DRM_PROP_NAME_LEN-1] = '\0';
        prop_enum->value = value;

        property->values[index] = value;
        list_add_tail(&prop_enum->head, &property->enum_blob_list);
        return 0;
}
EXPORT_SYMBOL(drm_property_add_enum);

/**
 * drm_property_destroy - destroy a drm property
 * @dev: drm device
 * @property: property to destry
 *
 * This function frees a property including any attached resources like
 * enumeration values.
 */
void drm_property_destroy(struct drm_device *dev, struct drm_property *property)
{
        struct drm_property_enum *prop_enum, *pt;

        list_for_each_entry_safe(prop_enum, pt, &property->enum_blob_list, head) {
                list_del(&prop_enum->head);
                kfree(prop_enum);
        }

        if (property->num_values)
                kfree(property->values);
        drm_mode_object_put(dev, &property->base);
        list_del(&property->head);
        kfree(property);
}
EXPORT_SYMBOL(drm_property_destroy);

/**
 * drm_object_attach_property - attach a property to a modeset object
 * @obj: drm modeset object
 * @property: property to attach
 * @init_val: initial value of the property
 *
 * This attaches the given property to the modeset object with the given initial
 * value. Currently this function cannot fail since the properties are stored in
 * a statically sized array.
 */
void drm_object_attach_property(struct drm_mode_object *obj,
                                struct drm_property *property,
                                uint64_t init_val)
{
        int count = obj->properties->count;

        if (count == DRM_OBJECT_MAX_PROPERTY) {
                WARN(1, "Failed to attach object property (type: 0x%x). Please "
                        "increase DRM_OBJECT_MAX_PROPERTY by 1 for each time "
                        "you see this message on the same object type.\n",
                        obj->type);
                return;
        }

        obj->properties->ids[count] = property->base.id;
        obj->properties->values[count] = init_val;
        obj->properties->count++;
}
EXPORT_SYMBOL(drm_object_attach_property);

/**
 * drm_object_property_set_value - set the value of a property
 * @obj: drm mode object to set property value for
 * @property: property to set
 * @val: value the property should be set to
 *
 * This functions sets a given property on a given object. This function only
 * changes the software state of the property, it does not call into the
 * driver's ->set_property callback.
 *
 * Returns:
 * Zero on success, error code on failure.
 */
int drm_object_property_set_value(struct drm_mode_object *obj,
                                  struct drm_property *property, uint64_t val)
{
        int i;

        for (i = 0; i < obj->properties->count; i++) {
                if (obj->properties->ids[i] == property->base.id) {
                        obj->properties->values[i] = val;
                        return 0;
                }
        }

        return -EINVAL;
}
EXPORT_SYMBOL(drm_object_property_set_value);

/**
 * drm_object_property_get_value - retrieve the value of a property
 * @obj: drm mode object to get property value from
 * @property: property to retrieve
 * @val: storage for the property value
 *
 * This function retrieves the softare state of the given property for the given
 * property. Since there is no driver callback to retrieve the current property
 * value this might be out of sync with the hardware, depending upon the driver
 * and property.
 *
 * Returns:
 * Zero on success, error code on failure.
 */
int drm_object_property_get_value(struct drm_mode_object *obj,
                                  struct drm_property *property, uint64_t *val)
{
        int i;

        for (i = 0; i < obj->properties->count; i++) {
                if (obj->properties->ids[i] == property->base.id) {
                        *val = obj->properties->values[i];
                        return 0;
                }
        }

        return -EINVAL;
}
EXPORT_SYMBOL(drm_object_property_get_value);

/**
 * drm_mode_getproperty_ioctl - get the current value of a connector's property
 * @dev: DRM device
 * @data: ioctl data
 * @file_priv: DRM file info
 *
 * This function retrieves the current value for an connectors's property.
 *
 * Called by the user via ioctl.
 *
 * Returns:
 * Zero on success, errno on failure.
 */
int drm_mode_getproperty_ioctl(struct drm_device *dev,
                               void *data, struct drm_file *file_priv)
{
        struct drm_mode_object *obj;
        struct drm_mode_get_property *out_resp = data;
        struct drm_property *property;
        int enum_count = 0;
        int blob_count = 0;
        int value_count = 0;
        int ret = 0, i;
        int copied;
        struct drm_property_enum *prop_enum;
        struct drm_mode_property_enum __user *enum_ptr;
        struct drm_property_blob *prop_blob;
        uint32_t __user *blob_id_ptr;
        uint64_t __user *values_ptr;
        uint32_t __user *blob_length_ptr;

        if (!drm_core_check_feature(dev, DRIVER_MODESET))
                return -EINVAL;

        drm_modeset_lock_all(dev);
        obj = drm_mode_object_find(dev, out_resp->prop_id, DRM_MODE_OBJECT_PROPERTY);
        if (!obj) {
                ret = -ENOENT;
                goto done;
        }
        property = obj_to_property(obj);

        if (property->flags & (DRM_MODE_PROP_ENUM | DRM_MODE_PROP_BITMASK)) {
                list_for_each_entry(prop_enum, &property->enum_blob_list, head)
                        enum_count++;
        } else if (property->flags & DRM_MODE_PROP_BLOB) {
                list_for_each_entry(prop_blob, &property->enum_blob_list, head)
                        blob_count++;
        }

        value_count = property->num_values;

        strncpy(out_resp->name, property->name, DRM_PROP_NAME_LEN);
        out_resp->name[DRM_PROP_NAME_LEN-1] = 0;
        out_resp->flags = property->flags;

        if ((out_resp->count_values >= value_count) && value_count) {
                values_ptr = (uint64_t __user *)(unsigned long)out_resp->values_ptr;
                for (i = 0; i < value_count; i++) {
                        if (copy_to_user(values_ptr + i, &property->values[i], sizeof(uint64_t))) {
                                ret = -EFAULT;
                                goto done;
                        }
                }
        }
        out_resp->count_values = value_count;

        if (property->flags & (DRM_MODE_PROP_ENUM | DRM_MODE_PROP_BITMASK)) {
                if ((out_resp->count_enum_blobs >= enum_count) && enum_count) {
                        copied = 0;
                        enum_ptr = (struct drm_mode_property_enum __user *)(unsigned long)out_resp->enum_blob_ptr;
                        list_for_each_entry(prop_enum, &property->enum_blob_list, head) {

                                if (copy_to_user(&enum_ptr[copied].value, &prop_enum->value, sizeof(uint64_t))) {
                                        ret = -EFAULT;
                                        goto done;
                                }

                                if (copy_to_user(&enum_ptr[copied].name,
                                                 &prop_enum->name, DRM_PROP_NAME_LEN)) {
                                        ret = -EFAULT;
                                        goto done;
                                }
                                copied++;
                        }
                }
                out_resp->count_enum_blobs = enum_count;
        }

        if (property->flags & DRM_MODE_PROP_BLOB) {
                if ((out_resp->count_enum_blobs >= blob_count) && blob_count) {
                        copied = 0;
                        blob_id_ptr = (uint32_t __user *)(unsigned long)out_resp->enum_blob_ptr;
                        blob_length_ptr = (uint32_t __user *)(unsigned long)out_resp->values_ptr;

                        list_for_each_entry(prop_blob, &property->enum_blob_list, head) {
                                if (put_user(prop_blob->base.id, blob_id_ptr + copied)) {
                                        ret = -EFAULT;
                                        goto done;
                                }

                                if (put_user(prop_blob->length, blob_length_ptr + copied)) {
                                        ret = -EFAULT;
                                        goto done;
                                }

                                copied++;
                        }
                }
                out_resp->count_enum_blobs = blob_count;
        }
done:
        drm_modeset_unlock_all(dev);
        return ret;
}

static struct drm_property_blob *drm_property_create_blob(struct drm_device *dev, int length,
                                                          void *data)
{
        struct drm_property_blob *blob;
        int ret;

        if (!length || !data)
                return NULL;

        blob = kzalloc(sizeof(struct drm_property_blob)+length, GFP_KERNEL);
        if (!blob)
                return NULL;

        ret = drm_mode_object_get(dev, &blob->base, DRM_MODE_OBJECT_BLOB);
        if (ret) {
                kfree(blob);
                return NULL;
        }

        blob->length = length;

        memcpy(blob->data, data, length);

        list_add_tail(&blob->head, &dev->mode_config.property_blob_list);
        return blob;
}

static void drm_property_destroy_blob(struct drm_device *dev,
                               struct drm_property_blob *blob)
{
        drm_mode_object_put(dev, &blob->base);
        list_del(&blob->head);
        kfree(blob);
}

/**
 * drm_mode_getblob_ioctl - get the contents of a blob property value
 * @dev: DRM device
 * @data: ioctl data
 * @file_priv: DRM file info
 *
 * This function retrieves the contents of a blob property. The value stored in
 * an object's blob property is just a normal modeset object id.
 *
 * Called by the user via ioctl.
 *
 * Returns:
 * Zero on success, errno on failure.
 */
int drm_mode_getblob_ioctl(struct drm_device *dev,
                           void *data, struct drm_file *file_priv)
{
        struct drm_mode_object *obj;
        struct drm_mode_get_blob *out_resp = data;
        struct drm_property_blob *blob;
        int ret = 0;
        void __user *blob_ptr;

        if (!drm_core_check_feature(dev, DRIVER_MODESET))
                return -EINVAL;

        drm_modeset_lock_all(dev);
        obj = drm_mode_object_find(dev, out_resp->blob_id, DRM_MODE_OBJECT_BLOB);
        if (!obj) {
                ret = -ENOENT;
                goto done;
        }
        blob = obj_to_blob(obj);

        if (out_resp->length == blob->length) {
                blob_ptr = (void __user *)(unsigned long)out_resp->data;
                if (copy_to_user(blob_ptr, blob->data, blob->length)){
                        ret = -EFAULT;
                        goto done;
                }
        }
        out_resp->length = blob->length;

done:
        drm_modeset_unlock_all(dev);
        return ret;
}

/**
 * drm_mode_connector_update_edid_property - update the edid property of a connector
 * @connector: drm connector
 * @edid: new value of the edid property
 *
 * This function creates a new blob modeset object and assigns its id to the
 * connector's edid property.
 *
 * Returns:
 * Zero on success, errno on failure.
 */
int drm_mode_connector_update_edid_property(struct drm_connector *connector,
                                            struct edid *edid)
{
        struct drm_device *dev = connector->dev;
        int ret, size;

        if (connector->edid_blob_ptr)
                drm_property_destroy_blob(dev, connector->edid_blob_ptr);

        /* Delete edid, when there is none. */
        if (!edid) {
                connector->edid_blob_ptr = NULL;
                ret = drm_object_property_set_value(&connector->base, dev->mode_config.edid_property, 0);
                return ret;
        }

        size = EDID_LENGTH * (1 + edid->extensions);
        connector->edid_blob_ptr = drm_property_create_blob(connector->dev,
                                                            size, edid);
        if (!connector->edid_blob_ptr)
                return -EINVAL;

        ret = drm_object_property_set_value(&connector->base,
                                               dev->mode_config.edid_property,
                                               connector->edid_blob_ptr->base.id);

        return ret;
}
EXPORT_SYMBOL(drm_mode_connector_update_edid_property);

static bool drm_property_change_is_valid(struct drm_property *property,
                                         uint64_t value)
{
        if (property->flags & DRM_MODE_PROP_IMMUTABLE)
                return false;
        if (property->flags & DRM_MODE_PROP_RANGE) {
                if (value < property->values[0] || value > property->values[1])
                        return false;
                return true;
        } else if (property->flags & DRM_MODE_PROP_BITMASK) {
                int i;
                uint64_t valid_mask = 0;
                for (i = 0; i < property->num_values; i++)
                        valid_mask |= (1ULL << property->values[i]);
                return !(value & ~valid_mask);
        } else if (property->flags & DRM_MODE_PROP_BLOB) {
                /* Only the driver knows */
                return true;
        } else {
                int i;
                for (i = 0; i < property->num_values; i++)
                        if (property->values[i] == value)
                                return true;
                return false;
        }
}

/**
 * drm_mode_connector_property_set_ioctl - set the current value of a connector property
 * @dev: DRM device
 * @data: ioctl data
 * @file_priv: DRM file info
 *
 * This function sets the current value for a connectors's property. It also
 * calls into a driver's ->set_property callback to update the hardware state
 *
 * Called by the user via ioctl.
 *
 * Returns:
 * Zero on success, errno on failure.
 */
int drm_mode_connector_property_set_ioctl(struct drm_device *dev,
                                       void *data, struct drm_file *file_priv)
{
        struct drm_mode_connector_set_property *conn_set_prop = data;
        struct drm_mode_obj_set_property obj_set_prop = {
                .value = conn_set_prop->value,
                .prop_id = conn_set_prop->prop_id,
                .obj_id = conn_set_prop->connector_id,
                .obj_type = DRM_MODE_OBJECT_CONNECTOR
        };

        /* It does all the locking and checking we need */
        return drm_mode_obj_set_property_ioctl(dev, &obj_set_prop, file_priv);
}

static int drm_mode_connector_set_obj_prop(struct drm_mode_object *obj,
                                           struct drm_property *property,
                                           uint64_t value)
{
        int ret = -EINVAL;
        struct drm_connector *connector = obj_to_connector(obj);

        /* Do DPMS ourselves */
        if (property == connector->dev->mode_config.dpms_property) {
                if (connector->funcs->dpms)
                        (*connector->funcs->dpms)(connector, (int)value);
                ret = 0;
        } else if (connector->funcs->set_property)
                ret = connector->funcs->set_property(connector, property, value);

        /* store the property value if successful */
        if (!ret)
                drm_object_property_set_value(&connector->base, property, value);
        return ret;
}

static int drm_mode_crtc_set_obj_prop(struct drm_mode_object *obj,
                                      struct drm_property *property,
                                      uint64_t value)
{
        int ret = -EINVAL;
        struct drm_crtc *crtc = obj_to_crtc(obj);

        if (crtc->funcs->set_property)
                ret = crtc->funcs->set_property(crtc, property, value);
        if (!ret)
                drm_object_property_set_value(obj, property, value);

        return ret;
}

static int drm_mode_plane_set_obj_prop(struct drm_mode_object *obj,
                                      struct drm_property *property,
                                      uint64_t value)
{
        int ret = -EINVAL;
        struct drm_plane *plane = obj_to_plane(obj);

        if (plane->funcs->set_property)
                ret = plane->funcs->set_property(plane, property, value);
        if (!ret)
                drm_object_property_set_value(obj, property, value);

        return ret;
}

/**
 * drm_mode_getproperty_ioctl - get the current value of a object's property
 * @dev: DRM device
 * @data: ioctl data
 * @file_priv: DRM file info
 *
 * This function retrieves the current value for an object's property. Compared
 * to the connector specific ioctl this one is extended to also work on crtc and
 * plane objects.
 *
 * Called by the user via ioctl.
 *
 * Returns:
 * Zero on success, errno on failure.
 */
int drm_mode_obj_get_properties_ioctl(struct drm_device *dev, void *data,
                                      struct drm_file *file_priv)
{
        struct drm_mode_obj_get_properties *arg = data;
        struct drm_mode_object *obj;
        int ret = 0;
        int i;
        int copied = 0;
        int props_count = 0;
        uint32_t __user *props_ptr;
        uint64_t __user *prop_values_ptr;

        if (!drm_core_check_feature(dev, DRIVER_MODESET))
                return -EINVAL;

        drm_modeset_lock_all(dev);

        obj = drm_mode_object_find(dev, arg->obj_id, arg->obj_type);
        if (!obj) {
                ret = -ENOENT;
                goto out;
        }
        if (!obj->properties) {
                ret = -EINVAL;
                goto out;
        }

        props_count = obj->properties->count;

        /* This ioctl is called twice, once to determine how much space is
         * needed, and the 2nd time to fill it. */
        if ((arg->count_props >= props_count) && props_count) {
                copied = 0;
                props_ptr = (uint32_t __user *)(unsigned long)(arg->props_ptr);
                prop_values_ptr = (uint64_t __user *)(unsigned long)
                                  (arg->prop_values_ptr);
                for (i = 0; i < props_count; i++) {
                        if (put_user(obj->properties->ids[i],
                                     props_ptr + copied)) {
                                ret = -EFAULT;
                                goto out;
                        }
                        if (put_user(obj->properties->values[i],
                                     prop_values_ptr + copied)) {
                                ret = -EFAULT;
                                goto out;
                        }
                        copied++;
                }
        }
        arg->count_props = props_count;
out:
        drm_modeset_unlock_all(dev);
        return ret;
}

/**
 * drm_mode_obj_set_property_ioctl - set the current value of an object's property
 * @dev: DRM device
 * @data: ioctl data
 * @file_priv: DRM file info
 *
 * This function sets the current value for an object's property. It also calls
 * into a driver's ->set_property callback to update the hardware state.
 * Compared to the connector specific ioctl this one is extended to also work on
 * crtc and plane objects.
 *
 * Called by the user via ioctl.
 *
 * Returns:
 * Zero on success, errno on failure.
 */
int drm_mode_obj_set_property_ioctl(struct drm_device *dev, void *data,
                                    struct drm_file *file_priv)
{
        struct drm_mode_obj_set_property *arg = data;
        struct drm_mode_object *arg_obj;
        struct drm_mode_object *prop_obj;
        struct drm_property *property;
        int ret = -EINVAL;
        int i;

        if (!drm_core_check_feature(dev, DRIVER_MODESET))
                return -EINVAL;

        drm_modeset_lock_all(dev);

        arg_obj = drm_mode_object_find(dev, arg->obj_id, arg->obj_type);
        if (!arg_obj) {
                ret = -ENOENT;
                goto out;
        }
        if (!arg_obj->properties)
                goto out;

        for (i = 0; i < arg_obj->properties->count; i++)
                if (arg_obj->properties->ids[i] == arg->prop_id)
                        break;

        if (i == arg_obj->properties->count)
                goto out;

        prop_obj = drm_mode_object_find(dev, arg->prop_id,
                                        DRM_MODE_OBJECT_PROPERTY);
        if (!prop_obj) {
                ret = -ENOENT;
                goto out;
        }
        property = obj_to_property(prop_obj);

        if (!drm_property_change_is_valid(property, arg->value))
                goto out;

        switch (arg_obj->type) {
        case DRM_MODE_OBJECT_CONNECTOR:
                ret = drm_mode_connector_set_obj_prop(arg_obj, property,
                                                      arg->value);
                break;
        case DRM_MODE_OBJECT_CRTC:
                ret = drm_mode_crtc_set_obj_prop(arg_obj, property, arg->value);
                break;
        case DRM_MODE_OBJECT_PLANE:
                ret = drm_mode_plane_set_obj_prop(arg_obj, property, arg->value);
                break;
        }

out:
        drm_modeset_unlock_all(dev);
        return ret;
}

/**
 * drm_mode_connector_attach_encoder - attach a connector to an encoder
 * @connector: connector to attach
 * @encoder: encoder to attach @connector to
 *
 * This function links up a connector to an encoder. Note that the routing
 * restrictions between encoders and crtcs are exposed to userspace through the
 * possible_clones and possible_crtcs bitmasks.
 *
 * Returns:
 * Zero on success, errno on failure.
 */
int drm_mode_connector_attach_encoder(struct drm_connector *connector,
                                      struct drm_encoder *encoder)
{
        int i;

        for (i = 0; i < DRM_CONNECTOR_MAX_ENCODER; i++) {
                if (connector->encoder_ids[i] == 0) {
                        connector->encoder_ids[i] = encoder->base.id;
                        return 0;
                }
        }
        return -ENOMEM;
}
EXPORT_SYMBOL(drm_mode_connector_attach_encoder);

/**
 * drm_mode_crtc_set_gamma_size - set the gamma table size
 * @crtc: CRTC to set the gamma table size for
 * @gamma_size: size of the gamma table
 *
 * Drivers which support gamma tables should set this to the supported gamma
 * table size when initializing the CRTC. Currently the drm core only supports a
 * fixed gamma table size.
 *
 * Returns:
 * Zero on success, errno on failure.
 */
int drm_mode_crtc_set_gamma_size(struct drm_crtc *crtc,
                                 int gamma_size)
{
        crtc->gamma_size = gamma_size;

        crtc->gamma_store = kzalloc(gamma_size * sizeof(uint16_t) * 3, GFP_KERNEL);
        if (!crtc->gamma_store) {
                crtc->gamma_size = 0;
                return -ENOMEM;
        }

        return 0;
}
EXPORT_SYMBOL(drm_mode_crtc_set_gamma_size);

/**
 * drm_mode_gamma_set_ioctl - set the gamma table
 * @dev: DRM device
 * @data: ioctl data
 * @file_priv: DRM file info
 *
 * Set the gamma table of a CRTC to the one passed in by the user. Userspace can
 * inquire the required gamma table size through drm_mode_gamma_get_ioctl.
 *
 * Called by the user via ioctl.
 *
 * Returns:
 * Zero on success, errno on failure.
 */
int drm_mode_gamma_set_ioctl(struct drm_device *dev,
                             void *data, struct drm_file *file_priv)
{
        struct drm_mode_crtc_lut *crtc_lut = data;
        struct drm_mode_object *obj;
        struct drm_crtc *crtc;
        void *r_base, *g_base, *b_base;
        int size;
        int ret = 0;

        if (!drm_core_check_feature(dev, DRIVER_MODESET))
                return -EINVAL;

        drm_modeset_lock_all(dev);
        obj = drm_mode_object_find(dev, crtc_lut->crtc_id, DRM_MODE_OBJECT_CRTC);
        if (!obj) {
                ret = -ENOENT;
                goto out;
        }
        crtc = obj_to_crtc(obj);

        if (crtc->funcs->gamma_set == NULL) {
                ret = -ENOSYS;
                goto out;
        }

        /* memcpy into gamma store */
        if (crtc_lut->gamma_size != crtc->gamma_size) {
                ret = -EINVAL;
                goto out;
        }

        size = crtc_lut->gamma_size * (sizeof(uint16_t));
        r_base = crtc->gamma_store;
        if (copy_from_user(r_base, (void __user *)(unsigned long)crtc_lut->red, size)) {
                ret = -EFAULT;
                goto out;
        }

        g_base = r_base + size;
        if (copy_from_user(g_base, (void __user *)(unsigned long)crtc_lut->green, size)) {
                ret = -EFAULT;
                goto out;
        }

        b_base = g_base + size;
        if (copy_from_user(b_base, (void __user *)(unsigned long)crtc_lut->blue, size)) {
                ret = -EFAULT;
                goto out;
        }

        crtc->funcs->gamma_set(crtc, r_base, g_base, b_base, 0, crtc->gamma_size);

out:
        drm_modeset_unlock_all(dev);
        return ret;

}

/**
 * drm_mode_gamma_get_ioctl - get the gamma table
 * @dev: DRM device
 * @data: ioctl data
 * @file_priv: DRM file info
 *
 * Copy the current gamma table into the storage provided. This also provides
 * the gamma table size the driver expects, which can be used to size the
 * allocated storage.
 *
 * Called by the user via ioctl.
 *
 * Returns:
 * Zero on success, errno on failure.
 */
int drm_mode_gamma_get_ioctl(struct drm_device *dev,
                             void *data, struct drm_file *file_priv)
{
        struct drm_mode_crtc_lut *crtc_lut = data;
        struct drm_mode_object *obj;
        struct drm_crtc *crtc;
        void *r_base, *g_base, *b_base;
        int size;
        int ret = 0;

        if (!drm_core_check_feature(dev, DRIVER_MODESET))
                return -EINVAL;

        drm_modeset_lock_all(dev);
        obj = drm_mode_object_find(dev, crtc_lut->crtc_id, DRM_MODE_OBJECT_CRTC);
        if (!obj) {
                ret = -ENOENT;
                goto out;
        }
        crtc = obj_to_crtc(obj);

        /* memcpy into gamma store */
        if (crtc_lut->gamma_size != crtc->gamma_size) {
                ret = -EINVAL;
                goto out;
        }

        size = crtc_lut->gamma_size * (sizeof(uint16_t));
        r_base = crtc->gamma_store;
        if (copy_to_user((void __user *)(unsigned long)crtc_lut->red, r_base, size)) {
                ret = -EFAULT;
                goto out;
        }

        g_base = r_base + size;
        if (copy_to_user((void __user *)(unsigned long)crtc_lut->green, g_base, size)) {
                ret = -EFAULT;
                goto out;
        }

        b_base = g_base + size;
        if (copy_to_user((void __user *)(unsigned long)crtc_lut->blue, b_base, size)) {
                ret = -EFAULT;
                goto out;
        }
out:
        drm_modeset_unlock_all(dev);
        return ret;
}

/**
 * drm_mode_page_flip_ioctl - schedule an asynchronous fb update
 * @dev: DRM device
 * @data: ioctl data
 * @file_priv: DRM file info
 *
 * This schedules an asynchronous update on a given CRTC, called page flip.
 * Optionally a drm event is generated to signal the completion of the event.
 * Generic drivers cannot assume that a pageflip with changed framebuffer
 * properties (including driver specific metadata like tiling layout) will work,
 * but some drivers support e.g. pixel format changes through the pageflip
 * ioctl.
 *
 * Called by the user via ioctl.
 *
 * Returns:
 * Zero on success, errno on failure.
 */
int drm_mode_page_flip_ioctl(struct drm_device *dev,
                             void *data, struct drm_file *file_priv)
{
        struct drm_mode_crtc_page_flip *page_flip = data;
        struct drm_mode_object *obj;
        struct drm_crtc *crtc;
        struct drm_framebuffer *fb = NULL, *old_fb = NULL;
        struct drm_pending_vblank_event *e = NULL;
        unsigned long flags;
        int ret = -EINVAL;

        if (page_flip->flags & ~DRM_MODE_PAGE_FLIP_FLAGS ||
            page_flip->reserved != 0)
                return -EINVAL;

        if ((page_flip->flags & DRM_MODE_PAGE_FLIP_ASYNC) && !dev->mode_config.async_page_flip)
                return -EINVAL;

        obj = drm_mode_object_find(dev, page_flip->crtc_id, DRM_MODE_OBJECT_CRTC);
        if (!obj)
                return -ENOENT;
        crtc = obj_to_crtc(obj);

        mutex_lock(&crtc->mutex);
        if (crtc->primary->fb == NULL) {
                /* The framebuffer is currently unbound, presumably
                 * due to a hotplug event, that userspace has not
                 * yet discovered.
                 */
                ret = -EBUSY;
                goto out;
        }

        if (crtc->funcs->page_flip == NULL)
                goto out;

        fb = drm_framebuffer_lookup(dev, page_flip->fb_id);
        if (!fb) {
                ret = -ENOENT;
                goto out;
        }

        ret = drm_crtc_check_viewport(crtc, crtc->x, crtc->y, &crtc->mode, fb);
        if (ret)
                goto out;

        if (crtc->primary->fb->pixel_format != fb->pixel_format) {
                DRM_DEBUG_KMS("Page flip is not allowed to change frame buffer format.\n");
                ret = -EINVAL;
                goto out;
        }

        if (page_flip->flags & DRM_MODE_PAGE_FLIP_EVENT) {
                ret = -ENOMEM;
                spin_lock_irqsave(&dev->event_lock, flags);
                if (file_priv->event_space < sizeof e->event) {
                        spin_unlock_irqrestore(&dev->event_lock, flags);
                        goto out;
                }
                file_priv->event_space -= sizeof e->event;
                spin_unlock_irqrestore(&dev->event_lock, flags);

                e = kzalloc(sizeof *e, GFP_KERNEL);
                if (e == NULL) {
                        spin_lock_irqsave(&dev->event_lock, flags);
                        file_priv->event_space += sizeof e->event;
                        spin_unlock_irqrestore(&dev->event_lock, flags);
                        goto out;
                }

                e->event.base.type = DRM_EVENT_FLIP_COMPLETE;
                e->event.base.length = sizeof e->event;
                e->event.user_data = page_flip->user_data;
                e->base.event = &e->event.base;
                e->base.file_priv = file_priv;
                e->base.destroy =
                        (void (*) (struct drm_pending_event *)) kfree;
        }

        old_fb = crtc->primary->fb;
        ret = crtc->funcs->page_flip(crtc, fb, e, page_flip->flags);
        if (ret) {
                if (page_flip->flags & DRM_MODE_PAGE_FLIP_EVENT) {
                        spin_lock_irqsave(&dev->event_lock, flags);
                        file_priv->event_space += sizeof e->event;
                        spin_unlock_irqrestore(&dev->event_lock, flags);
                        kfree(e);
                }
                /* Keep the old fb, don't unref it. */
                old_fb = NULL;
        } else {
                /*
                 * Warn if the driver hasn't properly updated the crtc->fb
                 * field to reflect that the new framebuffer is now used.
                 * Failing to do so will screw with the reference counting
                 * on framebuffers.
                 */
                WARN_ON(crtc->primary->fb != fb);
                /* Unref only the old framebuffer. */
                fb = NULL;
        }

out:
        if (fb)
                drm_framebuffer_unreference(fb);
        if (old_fb)
                drm_framebuffer_unreference(old_fb);
        mutex_unlock(&crtc->mutex);

        return ret;
}

/**
 * drm_mode_config_reset - call ->reset callbacks
 * @dev: drm device
 *
 * This functions calls all the crtc's, encoder's and connector's ->reset
 * callback. Drivers can use this in e.g. their driver load or resume code to
 * reset hardware and software state.
 */
void drm_mode_config_reset(struct drm_device *dev)
{
        struct drm_crtc *crtc;
        struct drm_encoder *encoder;
        struct drm_connector *connector;

        list_for_each_entry(crtc, &dev->mode_config.crtc_list, head)
                if (crtc->funcs->reset)
                        crtc->funcs->reset(crtc);

        list_for_each_entry(encoder, &dev->mode_config.encoder_list, head)
                if (encoder->funcs->reset)
                        encoder->funcs->reset(encoder);

        list_for_each_entry(connector, &dev->mode_config.connector_list, head) {
                connector->status = connector_status_unknown;

                if (connector->funcs->reset)
                        connector->funcs->reset(connector);
        }
}
EXPORT_SYMBOL(drm_mode_config_reset);

/**
 * drm_mode_create_dumb_ioctl - create a dumb backing storage buffer
 * @dev: DRM device
 * @data: ioctl data
 * @file_priv: DRM file info
 *
 * This creates a new dumb buffer in the driver's backing storage manager (GEM,
 * TTM or something else entirely) and returns the resulting buffer handle. This
 * handle can then be wrapped up into a framebuffer modeset object.
 *
 * Note that userspace is not allowed to use such objects for render
 * acceleration - drivers must create their own private ioctls for such a use
 * case.
 *
 * Called by the user via ioctl.
 *
 * Returns:
 * Zero on success, errno on failure.
 */
int drm_mode_create_dumb_ioctl(struct drm_device *dev,
                               void *data, struct drm_file *file_priv)
{
        struct drm_mode_create_dumb *args = data;
        u32 cpp, stride, size;

        if (!dev->driver->dumb_create)
                return -ENOSYS;
        if (!args->width || !args->height || !args->bpp)
                return -EINVAL;

        /* overflow checks for 32bit size calculations */
        cpp = DIV_ROUND_UP(args->bpp, 8);
        if (cpp > 0xffffffffU / args->width)
                return -EINVAL;
        stride = cpp * args->width;
        if (args->height > 0xffffffffU / stride)
                return -EINVAL;

        /* test for wrap-around */
        size = args->height * stride;
        if (PAGE_ALIGN(size) == 0)
                return -EINVAL;

        return dev->driver->dumb_create(file_priv, dev, args);
}

/**
 * drm_mode_mmap_dumb_ioctl - create an mmap offset for a dumb backing storage buffer
 * @dev: DRM device
 * @data: ioctl data
 * @file_priv: DRM file info
 *
 * Allocate an offset in the drm device node's address space to be able to
 * memory map a dumb buffer.
 *
 * Called by the user via ioctl.
 *
 * Returns:
 * Zero on success, errno on failure.
 */
int drm_mode_mmap_dumb_ioctl(struct drm_device *dev,
                             void *data, struct drm_file *file_priv)
{
        struct drm_mode_map_dumb *args = data;

        /* call driver ioctl to get mmap offset */
        if (!dev->driver->dumb_map_offset)
                return -ENOSYS;

        return dev->driver->dumb_map_offset(file_priv, dev, args->handle, &args->offset);
}

/**
 * drm_mode_destroy_dumb_ioctl - destroy a dumb backing strage buffer
 * @dev: DRM device
 * @data: ioctl data
 * @file_priv: DRM file info
 *
 * This destroys the userspace handle for the given dumb backing storage buffer.
 * Since buffer objects must be reference counted in the kernel a buffer object
 * won't be immediately freed if a framebuffer modeset object still uses it.
 *
 * Called by the user via ioctl.
 *
 * Returns:
 * Zero on success, errno on failure.
 */
int drm_mode_destroy_dumb_ioctl(struct drm_device *dev,
                                void *data, struct drm_file *file_priv)
{
        struct drm_mode_destroy_dumb *args = data;

        if (!dev->driver->dumb_destroy)
                return -ENOSYS;

        return dev->driver->dumb_destroy(file_priv, dev, args->handle);
}

/**
 * drm_fb_get_bpp_depth - get the bpp/depth values for format
 * @format: pixel format (DRM_FORMAT_*)
 * @depth: storage for the depth value
 * @bpp: storage for the bpp value
 *
 * This only supports RGB formats here for compat with code that doesn't use
 * pixel formats directly yet.
 */
void drm_fb_get_bpp_depth(uint32_t format, unsigned int *depth,
                          int *bpp)
{
        switch (format) {
        case DRM_FORMAT_C8:
        case DRM_FORMAT_RGB332:
        case DRM_FORMAT_BGR233:
                *depth = 8;
                *bpp = 8;
                break;
        case DRM_FORMAT_XRGB1555:
        case DRM_FORMAT_XBGR1555:
        case DRM_FORMAT_RGBX5551:
        case DRM_FORMAT_BGRX5551:
        case DRM_FORMAT_ARGB1555:
        case DRM_FORMAT_ABGR1555:
        case DRM_FORMAT_RGBA5551:
        case DRM_FORMAT_BGRA5551:
                *depth = 15;
                *bpp = 16;
                break;
        case DRM_FORMAT_RGB565:
        case DRM_FORMAT_BGR565:
                *depth = 16;
                *bpp = 16;
                break;
        case DRM_FORMAT_RGB888:
        case DRM_FORMAT_BGR888:
                *depth = 24;
                *bpp = 24;
                break;
        case DRM_FORMAT_XRGB8888:
        case DRM_FORMAT_XBGR8888:
        case DRM_FORMAT_RGBX8888:
        case DRM_FORMAT_BGRX8888:
                *depth = 24;
                *bpp = 32;
                break;
        case DRM_FORMAT_XRGB2101010:
        case DRM_FORMAT_XBGR2101010:
        case DRM_FORMAT_RGBX1010102:
        case DRM_FORMAT_BGRX1010102:
        case DRM_FORMAT_ARGB2101010:
        case DRM_FORMAT_ABGR2101010:
        case DRM_FORMAT_RGBA1010102:
        case DRM_FORMAT_BGRA1010102:
                *depth = 30;
                *bpp = 32;
                break;
        case DRM_FORMAT_ARGB8888:
        case DRM_FORMAT_ABGR8888:
        case DRM_FORMAT_RGBA8888:
        case DRM_FORMAT_BGRA8888:
                *depth = 32;
                *bpp = 32;
                break;
        default:
                DRM_DEBUG_KMS("unsupported pixel format %s\n",
                              drm_get_format_name(format));
                *depth = 0;
                *bpp = 0;
                break;
        }
}
EXPORT_SYMBOL(drm_fb_get_bpp_depth);

/**
 * drm_format_num_planes - get the number of planes for format
 * @format: pixel format (DRM_FORMAT_*)
 *
 * Returns:
 * The number of planes used by the specified pixel format.
 */
int drm_format_num_planes(uint32_t format)
{
        switch (format) {
        case DRM_FORMAT_YUV410:
        case DRM_FORMAT_YVU410:
        case DRM_FORMAT_YUV411:
        case DRM_FORMAT_YVU411:
        case DRM_FORMAT_YUV420:
        case DRM_FORMAT_YVU420:
        case DRM_FORMAT_YUV422:
        case DRM_FORMAT_YVU422:
        case DRM_FORMAT_YUV444:
        case DRM_FORMAT_YVU444:
                return 3;
        case DRM_FORMAT_NV12:
        case DRM_FORMAT_NV21:
        case DRM_FORMAT_NV16:
        case DRM_FORMAT_NV61:
        case DRM_FORMAT_NV24:
        case DRM_FORMAT_NV42:
                return 2;
        default:
                return 1;
        }
}
EXPORT_SYMBOL(drm_format_num_planes);

/**
 * drm_format_plane_cpp - determine the bytes per pixel value
 * @format: pixel format (DRM_FORMAT_*)
 * @plane: plane index
 *
 * Returns:
 * The bytes per pixel value for the specified plane.
 */
int drm_format_plane_cpp(uint32_t format, int plane)
{
        unsigned int depth;
        int bpp;

        if (plane >= drm_format_num_planes(format))
                return 0;

        switch (format) {
        case DRM_FORMAT_YUYV:
        case DRM_FORMAT_YVYU:
        case DRM_FORMAT_UYVY:
        case DRM_FORMAT_VYUY:
                return 2;
        case DRM_FORMAT_NV12:
        case DRM_FORMAT_NV21:
        case DRM_FORMAT_NV16:
        case DRM_FORMAT_NV61:
        case DRM_FORMAT_NV24:
        case DRM_FORMAT_NV42:
                return plane ? 2 : 1;
        case DRM_FORMAT_YUV410:
        case DRM_FORMAT_YVU410:
        case DRM_FORMAT_YUV411:
        case DRM_FORMAT_YVU411:
        case DRM_FORMAT_YUV420:
        case DRM_FORMAT_YVU420:
        case DRM_FORMAT_YUV422:
        case DRM_FORMAT_YVU422:
        case DRM_FORMAT_YUV444:
        case DRM_FORMAT_YVU444:
                return 1;
        default:
                drm_fb_get_bpp_depth(format, &depth, &bpp);
                return bpp >> 3;
        }
}
EXPORT_SYMBOL(drm_format_plane_cpp);

/**
 * drm_format_horz_chroma_subsampling - get the horizontal chroma subsampling factor
 * @format: pixel format (DRM_FORMAT_*)
 *
 * Returns:
 * The horizontal chroma subsampling factor for the
 * specified pixel format.
 */
int drm_format_horz_chroma_subsampling(uint32_t format)
{
        switch (format) {
        case DRM_FORMAT_YUV411:
        case DRM_FORMAT_YVU411:
        case DRM_FORMAT_YUV410:
        case DRM_FORMAT_YVU410:
                return 4;
        case DRM_FORMAT_YUYV:
        case DRM_FORMAT_YVYU:
        case DRM_FORMAT_UYVY:
        case DRM_FORMAT_VYUY:
        case DRM_FORMAT_NV12:
        case DRM_FORMAT_NV21:
        case DRM_FORMAT_NV16:
        case DRM_FORMAT_NV61:
        case DRM_FORMAT_YUV422:
        case DRM_FORMAT_YVU422:
        case DRM_FORMAT_YUV420:
        case DRM_FORMAT_YVU420:
                return 2;
        default:
                return 1;
        }
}
EXPORT_SYMBOL(drm_format_horz_chroma_subsampling);

/**
 * drm_format_vert_chroma_subsampling - get the vertical chroma subsampling factor
 * @format: pixel format (DRM_FORMAT_*)
 *
 * Returns:
 * The vertical chroma subsampling factor for the
 * specified pixel format.
 */
int drm_format_vert_chroma_subsampling(uint32_t format)
{
        switch (format) {
        case DRM_FORMAT_YUV410:
        case DRM_FORMAT_YVU410:
                return 4;
        case DRM_FORMAT_YUV420:
        case DRM_FORMAT_YVU420:
        case DRM_FORMAT_NV12:
        case DRM_FORMAT_NV21:
                return 2;
        default:
                return 1;
        }
}
EXPORT_SYMBOL(drm_format_vert_chroma_subsampling);

/**
 * drm_mode_config_init - initialize DRM mode_configuration structure
 * @dev: DRM device
 *
 * Initialize @dev's mode_config structure, used for tracking the graphics
 * configuration of @dev.
 *
 * Since this initializes the modeset locks, no locking is possible. Which is no
 * problem, since this should happen single threaded at init time. It is the
 * driver's problem to ensure this guarantee.
 *
 */
void drm_mode_config_init(struct drm_device *dev)
{
        mutex_init(&dev->mode_config.mutex);
        mutex_init(&dev->mode_config.idr_mutex);
        mutex_init(&dev->mode_config.fb_lock);
        INIT_LIST_HEAD(&dev->mode_config.fb_list);
        INIT_LIST_HEAD(&dev->mode_config.crtc_list);
        INIT_LIST_HEAD(&dev->mode_config.connector_list);
        INIT_LIST_HEAD(&dev->mode_config.bridge_list);
        INIT_LIST_HEAD(&dev->mode_config.encoder_list);
        INIT_LIST_HEAD(&dev->mode_config.property_list);
        INIT_LIST_HEAD(&dev->mode_config.property_blob_list);
        INIT_LIST_HEAD(&dev->mode_config.plane_list);
        idr_init(&dev->mode_config.crtc_idr);

        drm_modeset_lock_all(dev);
        drm_mode_create_standard_connector_properties(dev);
        drm_mode_create_standard_plane_properties(dev);
        drm_modeset_unlock_all(dev);

        /* Just to be sure */
        dev->mode_config.num_fb = 0;
        dev->mode_config.num_connector = 0;
        dev->mode_config.num_crtc = 0;
        dev->mode_config.num_encoder = 0;
        dev->mode_config.num_overlay_plane = 0;
        dev->mode_config.num_total_plane = 0;
}
EXPORT_SYMBOL(drm_mode_config_init);

/**
 * drm_mode_config_cleanup - free up DRM mode_config info
 * @dev: DRM device
 *
 * Free up all the connectors and CRTCs associated with this DRM device, then
 * free up the framebuffers and associated buffer objects.
 *
 * Note that since this /should/ happen single-threaded at driver/device
 * teardown time, no locking is required. It's the driver's job to ensure that
 * this guarantee actually holds true.
 *
 * FIXME: cleanup any dangling user buffer objects too
 */
void drm_mode_config_cleanup(struct drm_device *dev)
{
        struct drm_connector *connector, *ot;
        struct drm_crtc *crtc, *ct;
        struct drm_encoder *encoder, *enct;
        struct drm_bridge *bridge, *brt;
        struct drm_framebuffer *fb, *fbt;
        struct drm_property *property, *pt;
        struct drm_property_blob *blob, *bt;
        struct drm_plane *plane, *plt;

        list_for_each_entry_safe(encoder, enct, &dev->mode_config.encoder_list,
                                 head) {
                encoder->funcs->destroy(encoder);
        }

        list_for_each_entry_safe(bridge, brt,
                                 &dev->mode_config.bridge_list, head) {
                bridge->funcs->destroy(bridge);
        }

        list_for_each_entry_safe(connector, ot,
                                 &dev->mode_config.connector_list, head) {
                connector->funcs->destroy(connector);
        }

        list_for_each_entry_safe(property, pt, &dev->mode_config.property_list,
                                 head) {
                drm_property_destroy(dev, property);
        }

        list_for_each_entry_safe(blob, bt, &dev->mode_config.property_blob_list,
                                 head) {
                drm_property_destroy_blob(dev, blob);
        }

        /*
         * Single-threaded teardown context, so it's not required to grab the
         * fb_lock to protect against concurrent fb_list access. Contrary, it
         * would actually deadlock with the drm_framebuffer_cleanup function.
         *
         * Also, if there are any framebuffers left, that's a driver leak now,
         * so politely WARN about this.
         */
        WARN_ON(!list_empty(&dev->mode_config.fb_list));
        list_for_each_entry_safe(fb, fbt, &dev->mode_config.fb_list, head) {
                drm_framebuffer_remove(fb);
        }

        list_for_each_entry_safe(plane, plt, &dev->mode_config.plane_list,
                                 head) {
                plane->funcs->destroy(plane);
        }

        list_for_each_entry_safe(crtc, ct, &dev->mode_config.crtc_list, head) {
                crtc->funcs->destroy(crtc);
        }

        idr_destroy(&dev->mode_config.crtc_idr);
}
EXPORT_SYMBOL(drm_mode_config_cleanup);