[media] v4l: vsp1: uds: Fix scaling of alpha layer
authorLaurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Sat, 31 May 2014 00:45:48 +0000 (21:45 -0300)
committerMauro Carvalho Chehab <m.chehab@samsung.com>
Thu, 17 Jul 2014 15:45:00 +0000 (12:45 -0300)
Pixel color components can be scaled using either bilinear interpolation
or a multitap filter. The multitap filter provides better results, but
can't be selected when the alpha layer need to be scaled down by more
than 1/2.

Disable alpha scaling when the input has a fixed alpha value, and
program the UDS to output a fixed alpha value in that case. This ensures
the multitap filter will be used whenever possible.

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>
drivers/media/platform/vsp1/vsp1_rpf.c
drivers/media/platform/vsp1/vsp1_uds.c
drivers/media/platform/vsp1/vsp1_uds.h
drivers/media/platform/vsp1/vsp1_video.c
drivers/media/platform/vsp1/vsp1_video.h

index 576779f2332b92b3654af2afa01fc2a517684725..d14d26b718efe14ae2a2c69a1650d048d4eee22d 100644 (file)
@@ -46,6 +46,7 @@ static int rpf_s_ctrl(struct v4l2_ctrl *ctrl)
 {
        struct vsp1_rwpf *rpf =
                container_of(ctrl->handler, struct vsp1_rwpf, ctrls);
+       struct vsp1_pipeline *pipe;
 
        if (!vsp1_entity_is_streaming(&rpf->entity))
                return 0;
@@ -54,6 +55,9 @@ static int rpf_s_ctrl(struct v4l2_ctrl *ctrl)
        case V4L2_CID_ALPHA_COMPONENT:
                vsp1_rpf_write(rpf, VI6_RPF_VRTCOL_SET,
                               ctrl->val << VI6_RPF_VRTCOL_SET_LAYA_SHIFT);
+
+               pipe = to_vsp1_pipeline(&rpf->entity.subdev.entity);
+               vsp1_pipeline_propagate_alpha(pipe, &rpf->entity, ctrl->val);
                break;
        }
 
index 0293bdbb4401a30b318e8d663835a31ebec637f1..de92ef4944b3c97b533b0e0ca27541330bbd8be0 100644 (file)
@@ -45,6 +45,11 @@ static inline void vsp1_uds_write(struct vsp1_uds *uds, u32 reg, u32 data)
  * Scaling Computation
  */
 
+void vsp1_uds_set_alpha(struct vsp1_uds *uds, unsigned int alpha)
+{
+       vsp1_uds_write(uds, VI6_UDS_ALPVAL, alpha << VI6_UDS_ALPVAL_VAL0_SHIFT);
+}
+
 /*
  * uds_output_size - Return the output size for an input size and scaling ratio
  * @input: input size in pixels
@@ -105,49 +110,56 @@ static unsigned int uds_compute_ratio(unsigned int input, unsigned int output)
        return (input - 1) * 4096 / (output - 1);
 }
 
-static void uds_compute_ratios(struct vsp1_uds *uds)
-{
-       struct v4l2_mbus_framefmt *input = &uds->entity.formats[UDS_PAD_SINK];
-       struct v4l2_mbus_framefmt *output =
-               &uds->entity.formats[UDS_PAD_SOURCE];
-
-       uds->hscale = uds_compute_ratio(input->width, output->width);
-       uds->vscale = uds_compute_ratio(input->height, output->height);
-
-       dev_dbg(uds->entity.vsp1->dev, "hscale %u vscale %u\n",
-               uds->hscale, uds->vscale);
-}
-
 /* -----------------------------------------------------------------------------
  * V4L2 Subdevice Core Operations
  */
 
 static int uds_s_stream(struct v4l2_subdev *subdev, int enable)
 {
-       const struct v4l2_mbus_framefmt *format;
        struct vsp1_uds *uds = to_uds(subdev);
+       const struct v4l2_mbus_framefmt *output;
+       const struct v4l2_mbus_framefmt *input;
+       unsigned int hscale;
+       unsigned int vscale;
+       bool multitap;
 
        if (!enable)
                return 0;
 
-       /* Enable multi-tap scaling. */
-       vsp1_uds_write(uds, VI6_UDS_CTRL, VI6_UDS_CTRL_AON | VI6_UDS_CTRL_BC);
+       input = &uds->entity.formats[UDS_PAD_SINK];
+       output = &uds->entity.formats[UDS_PAD_SOURCE];
+
+       hscale = uds_compute_ratio(input->width, output->width);
+       vscale = uds_compute_ratio(input->height, output->height);
+
+       dev_dbg(uds->entity.vsp1->dev, "hscale %u vscale %u\n", hscale, vscale);
+
+       /* Multi-tap scaling can't be enabled along with alpha scaling when
+        * scaling down with a factor lower than or equal to 1/2 in either
+        * direction.
+        */
+       if (uds->scale_alpha && (hscale >= 8192 || vscale >= 8192))
+               multitap = false;
+       else
+               multitap = true;
+
+       vsp1_uds_write(uds, VI6_UDS_CTRL,
+                      (uds->scale_alpha ? VI6_UDS_CTRL_AON : 0) |
+                      (multitap ? VI6_UDS_CTRL_BC : 0));
 
        vsp1_uds_write(uds, VI6_UDS_PASS_BWIDTH,
-                      (uds_passband_width(uds->hscale)
+                      (uds_passband_width(hscale)
                                << VI6_UDS_PASS_BWIDTH_H_SHIFT) |
-                      (uds_passband_width(uds->vscale)
+                      (uds_passband_width(vscale)
                                << VI6_UDS_PASS_BWIDTH_V_SHIFT));
 
        /* Set the scaling ratios and the output size. */
-       format = &uds->entity.formats[UDS_PAD_SOURCE];
-
        vsp1_uds_write(uds, VI6_UDS_SCALE,
-                      (uds->hscale << VI6_UDS_SCALE_HFRAC_SHIFT) |
-                      (uds->vscale << VI6_UDS_SCALE_VFRAC_SHIFT));
+                      (hscale << VI6_UDS_SCALE_HFRAC_SHIFT) |
+                      (vscale << VI6_UDS_SCALE_VFRAC_SHIFT));
        vsp1_uds_write(uds, VI6_UDS_CLIP_SIZE,
-                      (format->width << VI6_UDS_CLIP_SIZE_HSIZE_SHIFT) |
-                      (format->height << VI6_UDS_CLIP_SIZE_VSIZE_SHIFT));
+                      (output->width << VI6_UDS_CLIP_SIZE_HSIZE_SHIFT) |
+                      (output->height << VI6_UDS_CLIP_SIZE_VSIZE_SHIFT));
 
        return 0;
 }
@@ -280,9 +292,6 @@ static int uds_set_format(struct v4l2_subdev *subdev, struct v4l2_subdev_fh *fh,
                uds_try_format(uds, fh, UDS_PAD_SOURCE, format, fmt->which);
        }
 
-       if (fmt->which == V4L2_SUBDEV_FORMAT_ACTIVE)
-               uds_compute_ratios(uds);
-
        return 0;
 }
 
index 479d12df118057df4edc10bf11e8d973894aacdb..031ac0da1b667c9a535f03dd4d2fd586eedb8ecd 100644 (file)
@@ -25,9 +25,7 @@ struct vsp1_device;
 
 struct vsp1_uds {
        struct vsp1_entity entity;
-
-       unsigned int hscale;
-       unsigned int vscale;
+       bool scale_alpha;
 };
 
 static inline struct vsp1_uds *to_uds(struct v4l2_subdev *subdev)
@@ -37,4 +35,6 @@ static inline struct vsp1_uds *to_uds(struct v4l2_subdev *subdev)
 
 struct vsp1_uds *vsp1_uds_create(struct vsp1_device *vsp1, unsigned int index);
 
+void vsp1_uds_set_alpha(struct vsp1_uds *uds, unsigned int alpha);
+
 #endif /* __VSP1_UDS_H__ */
index 58fc076197f1a419f63582ae646eb02b952be738..915a20eb003e032632b906ba3eccd2f5c165f210 100644 (file)
@@ -31,6 +31,7 @@
 #include "vsp1_bru.h"
 #include "vsp1_entity.h"
 #include "vsp1_rwpf.h"
+#include "vsp1_uds.h"
 #include "vsp1_video.h"
 
 #define VSP1_VIDEO_DEF_FORMAT          V4L2_PIX_FMT_YUYV
@@ -306,13 +307,14 @@ vsp1_video_format_adjust(struct vsp1_video *video,
  * Pipeline Management
  */
 
-static int vsp1_pipeline_validate_branch(struct vsp1_rwpf *input,
+static int vsp1_pipeline_validate_branch(struct vsp1_pipeline *pipe,
+                                        struct vsp1_rwpf *input,
                                         struct vsp1_rwpf *output)
 {
        struct vsp1_entity *entity;
        unsigned int entities = 0;
        struct media_pad *pad;
-       bool uds_found = false;
+       bool bru_found = false;
 
        input->location.left = 0;
        input->location.top = 0;
@@ -341,6 +343,8 @@ static int vsp1_pipeline_validate_branch(struct vsp1_rwpf *input,
 
                        input->location.left = rect->left;
                        input->location.top = rect->top;
+
+                       bru_found = true;
                }
 
                /* We've reached the WPF, we're done. */
@@ -355,9 +359,12 @@ static int vsp1_pipeline_validate_branch(struct vsp1_rwpf *input,
 
                /* UDS can't be chained. */
                if (entity->type == VSP1_ENTITY_UDS) {
-                       if (uds_found)
+                       if (pipe->uds)
                                return -EPIPE;
-                       uds_found = true;
+
+                       pipe->uds = entity;
+                       pipe->uds_input = bru_found ? pipe->bru
+                                       : &input->entity;
                }
 
                /* Follow the source link. The link setup operations ensure
@@ -394,6 +401,7 @@ static void __vsp1_pipeline_cleanup(struct vsp1_pipeline *pipe)
        pipe->output = NULL;
        pipe->bru = NULL;
        pipe->lif = NULL;
+       pipe->uds = NULL;
 }
 
 static int vsp1_pipeline_validate(struct vsp1_pipeline *pipe,
@@ -451,7 +459,7 @@ static int vsp1_pipeline_validate(struct vsp1_pipeline *pipe,
         * contains no loop and that all branches end at the output WPF.
         */
        for (i = 0; i < pipe->num_inputs; ++i) {
-               ret = vsp1_pipeline_validate_branch(pipe->inputs[i],
+               ret = vsp1_pipeline_validate_branch(pipe, pipe->inputs[i],
                                                    pipe->output);
                if (ret < 0)
                        goto error;
@@ -654,6 +662,47 @@ done:
        spin_unlock_irqrestore(&pipe->irqlock, flags);
 }
 
+/*
+ * Propagate the alpha value through the pipeline.
+ *
+ * As the UDS has restricted scaling capabilities when the alpha component needs
+ * to be scaled, we disable alpha scaling when the UDS input has a fixed alpha
+ * value. The UDS then outputs a fixed alpha value which needs to be programmed
+ * from the input RPF alpha.
+ */
+void vsp1_pipeline_propagate_alpha(struct vsp1_pipeline *pipe,
+                                  struct vsp1_entity *input,
+                                  unsigned int alpha)
+{
+       struct vsp1_entity *entity;
+       struct media_pad *pad;
+
+       pad = media_entity_remote_pad(&input->pads[RWPF_PAD_SOURCE]);
+
+       while (pad) {
+               if (media_entity_type(pad->entity) != MEDIA_ENT_T_V4L2_SUBDEV)
+                       break;
+
+               entity = to_vsp1_entity(media_entity_to_v4l2_subdev(pad->entity));
+
+               /* The BRU background color has a fixed alpha value set to 255,
+                * the output alpha value is thus always equal to 255.
+                */
+               if (entity->type == VSP1_ENTITY_BRU)
+                       alpha = 255;
+
+               if (entity->type == VSP1_ENTITY_UDS) {
+                       struct vsp1_uds *uds = to_uds(&entity->subdev);
+
+                       vsp1_uds_set_alpha(uds, alpha);
+                       break;
+               }
+
+               pad = &entity->pads[entity->source_pad];
+               pad = media_entity_remote_pad(pad);
+       }
+}
+
 /* -----------------------------------------------------------------------------
  * videobuf2 Queue Operations
  */
@@ -761,6 +810,25 @@ static int vsp1_video_start_streaming(struct vb2_queue *vq, unsigned int count)
 
        mutex_lock(&pipe->lock);
        if (pipe->stream_count == pipe->num_video - 1) {
+               if (pipe->uds) {
+                       struct vsp1_uds *uds = to_uds(&pipe->uds->subdev);
+
+                       /* If a BRU is present in the pipeline before the UDS,
+                        * the alpha component doesn't need to be scaled as the
+                        * BRU output alpha value is fixed to 255. Otherwise we
+                        * need to scale the alpha component only when available
+                        * at the input RPF.
+                        */
+                       if (pipe->uds_input->type == VSP1_ENTITY_BRU) {
+                               uds->scale_alpha = false;
+                       } else {
+                               struct vsp1_rwpf *rpf =
+                                       to_rwpf(&pipe->uds_input->subdev);
+
+                               uds->scale_alpha = rpf->video.fmtinfo->alpha;
+                       }
+               }
+
                list_for_each_entry(entity, &pipe->entities, list_pipe) {
                        vsp1_entity_route_setup(entity);
 
index 4dad110b2e6950fb5bcc852eaba68a15ca5113ea..fd2851a82e0019e314fafb96868c406ed7b68b33 100644 (file)
@@ -79,6 +79,8 @@ struct vsp1_pipeline {
        struct vsp1_rwpf *output;
        struct vsp1_entity *bru;
        struct vsp1_entity *lif;
+       struct vsp1_entity *uds;
+       struct vsp1_entity *uds_input;
 
        struct list_head entities;
 };
@@ -143,4 +145,8 @@ void vsp1_video_cleanup(struct vsp1_video *video);
 
 void vsp1_pipeline_frame_end(struct vsp1_pipeline *pipe);
 
+void vsp1_pipeline_propagate_alpha(struct vsp1_pipeline *pipe,
+                                  struct vsp1_entity *input,
+                                  unsigned int alpha);
+
 #endif /* __VSP1_VIDEO_H__ */