2 * inode.c -- user mode filesystem api for usb gadget controllers
4 * Copyright (C) 2003-2004 David Brownell
5 * Copyright (C) 2003 Agilent Technologies
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 2 of the License, or
10 * (at your option) any later version.
14 /* #define VERBOSE_DEBUG */
16 #include <linux/init.h>
17 #include <linux/module.h>
19 #include <linux/pagemap.h>
20 #include <linux/uts.h>
21 #include <linux/wait.h>
22 #include <linux/compiler.h>
23 #include <asm/uaccess.h>
24 #include <linux/sched.h>
25 #include <linux/slab.h>
26 #include <linux/poll.h>
27 #include <linux/mmu_context.h>
28 #include <linux/aio.h>
30 #include <linux/device.h>
31 #include <linux/moduleparam.h>
33 #include <linux/usb/gadgetfs.h>
34 #include <linux/usb/gadget.h>
38 * The gadgetfs API maps each endpoint to a file descriptor so that you
39 * can use standard synchronous read/write calls for I/O. There's some
40 * O_NONBLOCK and O_ASYNC/FASYNC style i/o support. Example usermode
41 * drivers show how this works in practice. You can also use AIO to
42 * eliminate I/O gaps between requests, to help when streaming data.
44 * Key parts that must be USB-specific are protocols defining how the
45 * read/write operations relate to the hardware state machines. There
46 * are two types of files. One type is for the device, implementing ep0.
47 * The other type is for each IN or OUT endpoint. In both cases, the
48 * user mode driver must configure the hardware before using it.
50 * - First, dev_config() is called when /dev/gadget/$CHIP is configured
51 * (by writing configuration and device descriptors). Afterwards it
52 * may serve as a source of device events, used to handle all control
53 * requests other than basic enumeration.
55 * - Then, after a SET_CONFIGURATION control request, ep_config() is
56 * called when each /dev/gadget/ep* file is configured (by writing
57 * endpoint descriptors). Afterwards these files are used to write()
58 * IN data or to read() OUT data. To halt the endpoint, a "wrong
59 * direction" request is issued (like reading an IN endpoint).
61 * Unlike "usbfs" the only ioctl()s are for things that are rare, and maybe
62 * not possible on all hardware. For example, precise fault handling with
63 * respect to data left in endpoint fifos after aborted operations; or
64 * selective clearing of endpoint halts, to implement SET_INTERFACE.
67 #define DRIVER_DESC "USB Gadget filesystem"
68 #define DRIVER_VERSION "24 Aug 2004"
70 static const char driver_desc [] = DRIVER_DESC;
71 static const char shortname [] = "gadgetfs";
73 MODULE_DESCRIPTION (DRIVER_DESC);
74 MODULE_AUTHOR ("David Brownell");
75 MODULE_LICENSE ("GPL");
78 /*----------------------------------------------------------------------*/
80 #define GADGETFS_MAGIC 0xaee71ee7
82 /* /dev/gadget/$CHIP represents ep0 and the whole device */
84 /* DISBLED is the initial state.
86 STATE_DEV_DISABLED = 0,
88 /* Only one open() of /dev/gadget/$CHIP; only one file tracks
89 * ep0/device i/o modes and binding to the controller. Driver
90 * must always write descriptors to initialize the device, then
91 * the device becomes UNCONNECTED until enumeration.
95 /* From then on, ep0 fd is in either of two basic modes:
96 * - (UN)CONNECTED: read usb_gadgetfs_event(s) from it
97 * - SETUP: read/write will transfer control data and succeed;
98 * or if "wrong direction", performs protocol stall
100 STATE_DEV_UNCONNECTED,
104 /* UNBOUND means the driver closed ep0, so the device won't be
105 * accessible again (DEV_DISABLED) until all fds are closed.
110 /* enough for the whole queue: most events invalidate others */
116 enum ep0_state state; /* P: lock */
117 struct usb_gadgetfs_event event [N_EVENT];
119 struct fasync_struct *fasync;
122 /* drivers reading ep0 MUST handle control requests (SETUP)
123 * reported that way; else the host will time out.
125 unsigned usermode_setup : 1,
131 unsigned setup_wLength;
133 /* the rest is basically write-once */
134 struct usb_config_descriptor *config, *hs_config;
135 struct usb_device_descriptor *dev;
136 struct usb_request *req;
137 struct usb_gadget *gadget;
138 struct list_head epfiles;
140 wait_queue_head_t wait;
141 struct super_block *sb;
142 struct dentry *dentry;
144 /* except this scratch i/o buffer for ep0 */
148 static inline void get_dev (struct dev_data *data)
150 atomic_inc (&data->count);
153 static void put_dev (struct dev_data *data)
155 if (likely (!atomic_dec_and_test (&data->count)))
157 /* needs no more cleanup */
158 BUG_ON (waitqueue_active (&data->wait));
162 static struct dev_data *dev_new (void)
164 struct dev_data *dev;
166 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
169 dev->state = STATE_DEV_DISABLED;
170 atomic_set (&dev->count, 1);
171 spin_lock_init (&dev->lock);
172 INIT_LIST_HEAD (&dev->epfiles);
173 init_waitqueue_head (&dev->wait);
177 /*----------------------------------------------------------------------*/
179 /* other /dev/gadget/$ENDPOINT files represent endpoints */
181 STATE_EP_DISABLED = 0,
191 struct dev_data *dev;
192 /* must hold dev->lock before accessing ep or req */
194 struct usb_request *req;
197 struct usb_endpoint_descriptor desc, hs_desc;
198 struct list_head epfiles;
199 wait_queue_head_t wait;
200 struct dentry *dentry;
203 static inline void get_ep (struct ep_data *data)
205 atomic_inc (&data->count);
208 static void put_ep (struct ep_data *data)
210 if (likely (!atomic_dec_and_test (&data->count)))
213 /* needs no more cleanup */
214 BUG_ON (!list_empty (&data->epfiles));
215 BUG_ON (waitqueue_active (&data->wait));
219 /*----------------------------------------------------------------------*/
221 /* most "how to use the hardware" policy choices are in userspace:
222 * mapping endpoint roles (which the driver needs) to the capabilities
223 * which the usb controller has. most of those capabilities are exposed
224 * implicitly, starting with the driver name and then endpoint names.
227 static const char *CHIP;
229 /*----------------------------------------------------------------------*/
231 /* NOTE: don't use dev_printk calls before binding to the gadget
232 * at the end of ep0 configuration, or after unbind.
235 /* too wordy: dev_printk(level , &(d)->gadget->dev , fmt , ## args) */
236 #define xprintk(d,level,fmt,args...) \
237 printk(level "%s: " fmt , shortname , ## args)
240 #define DBG(dev,fmt,args...) \
241 xprintk(dev , KERN_DEBUG , fmt , ## args)
243 #define DBG(dev,fmt,args...) \
250 #define VDEBUG(dev,fmt,args...) \
254 #define ERROR(dev,fmt,args...) \
255 xprintk(dev , KERN_ERR , fmt , ## args)
256 #define INFO(dev,fmt,args...) \
257 xprintk(dev , KERN_INFO , fmt , ## args)
260 /*----------------------------------------------------------------------*/
262 /* SYNCHRONOUS ENDPOINT OPERATIONS (bulk/intr/iso)
264 * After opening, configure non-control endpoints. Then use normal
265 * stream read() and write() requests; and maybe ioctl() to get more
266 * precise FIFO status when recovering from cancellation.
269 static void epio_complete (struct usb_ep *ep, struct usb_request *req)
271 struct ep_data *epdata = ep->driver_data;
276 epdata->status = req->status;
278 epdata->status = req->actual;
279 complete ((struct completion *)req->context);
282 /* tasklock endpoint, returning when it's connected.
283 * still need dev->lock to use epdata->ep.
286 get_ready_ep (unsigned f_flags, struct ep_data *epdata)
290 if (f_flags & O_NONBLOCK) {
291 if (!mutex_trylock(&epdata->lock))
293 if (epdata->state != STATE_EP_ENABLED) {
294 mutex_unlock(&epdata->lock);
302 val = mutex_lock_interruptible(&epdata->lock);
306 switch (epdata->state) {
307 case STATE_EP_ENABLED:
309 // case STATE_EP_DISABLED: /* "can't happen" */
310 // case STATE_EP_READY: /* "can't happen" */
311 default: /* error! */
312 pr_debug ("%s: ep %p not available, state %d\n",
313 shortname, epdata, epdata->state);
315 case STATE_EP_UNBOUND: /* clean disconnect */
317 mutex_unlock(&epdata->lock);
323 ep_io (struct ep_data *epdata, void *buf, unsigned len)
325 DECLARE_COMPLETION_ONSTACK (done);
328 spin_lock_irq (&epdata->dev->lock);
329 if (likely (epdata->ep != NULL)) {
330 struct usb_request *req = epdata->req;
332 req->context = &done;
333 req->complete = epio_complete;
336 value = usb_ep_queue (epdata->ep, req, GFP_ATOMIC);
339 spin_unlock_irq (&epdata->dev->lock);
341 if (likely (value == 0)) {
342 value = wait_event_interruptible (done.wait, done.done);
344 spin_lock_irq (&epdata->dev->lock);
345 if (likely (epdata->ep != NULL)) {
346 DBG (epdata->dev, "%s i/o interrupted\n",
348 usb_ep_dequeue (epdata->ep, epdata->req);
349 spin_unlock_irq (&epdata->dev->lock);
351 wait_event (done.wait, done.done);
352 if (epdata->status == -ECONNRESET)
353 epdata->status = -EINTR;
355 spin_unlock_irq (&epdata->dev->lock);
357 DBG (epdata->dev, "endpoint gone\n");
358 epdata->status = -ENODEV;
361 return epdata->status;
367 /* handle a synchronous OUT bulk/intr/iso transfer */
369 ep_read (struct file *fd, char __user *buf, size_t len, loff_t *ptr)
371 struct ep_data *data = fd->private_data;
375 if ((value = get_ready_ep (fd->f_flags, data)) < 0)
378 /* halt any endpoint by doing a "wrong direction" i/o call */
379 if (usb_endpoint_dir_in(&data->desc)) {
380 if (usb_endpoint_xfer_isoc(&data->desc)) {
381 mutex_unlock(&data->lock);
384 DBG (data->dev, "%s halt\n", data->name);
385 spin_lock_irq (&data->dev->lock);
386 if (likely (data->ep != NULL))
387 usb_ep_set_halt (data->ep);
388 spin_unlock_irq (&data->dev->lock);
389 mutex_unlock(&data->lock);
393 /* FIXME readahead for O_NONBLOCK and poll(); careful with ZLPs */
396 kbuf = kmalloc (len, GFP_KERNEL);
397 if (unlikely (!kbuf))
400 value = ep_io (data, kbuf, len);
401 VDEBUG (data->dev, "%s read %zu OUT, status %d\n",
402 data->name, len, (int) value);
403 if (value >= 0 && copy_to_user (buf, kbuf, value))
407 mutex_unlock(&data->lock);
412 /* handle a synchronous IN bulk/intr/iso transfer */
414 ep_write (struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
416 struct ep_data *data = fd->private_data;
420 if ((value = get_ready_ep (fd->f_flags, data)) < 0)
423 /* halt any endpoint by doing a "wrong direction" i/o call */
424 if (!usb_endpoint_dir_in(&data->desc)) {
425 if (usb_endpoint_xfer_isoc(&data->desc)) {
426 mutex_unlock(&data->lock);
429 DBG (data->dev, "%s halt\n", data->name);
430 spin_lock_irq (&data->dev->lock);
431 if (likely (data->ep != NULL))
432 usb_ep_set_halt (data->ep);
433 spin_unlock_irq (&data->dev->lock);
434 mutex_unlock(&data->lock);
438 /* FIXME writebehind for O_NONBLOCK and poll(), qlen = 1 */
441 kbuf = memdup_user(buf, len);
443 value = PTR_ERR(kbuf);
448 value = ep_io (data, kbuf, len);
449 VDEBUG (data->dev, "%s write %zu IN, status %d\n",
450 data->name, len, (int) value);
452 mutex_unlock(&data->lock);
458 ep_release (struct inode *inode, struct file *fd)
460 struct ep_data *data = fd->private_data;
463 value = mutex_lock_interruptible(&data->lock);
467 /* clean up if this can be reopened */
468 if (data->state != STATE_EP_UNBOUND) {
469 data->state = STATE_EP_DISABLED;
470 data->desc.bDescriptorType = 0;
471 data->hs_desc.bDescriptorType = 0;
472 usb_ep_disable(data->ep);
474 mutex_unlock(&data->lock);
479 static long ep_ioctl(struct file *fd, unsigned code, unsigned long value)
481 struct ep_data *data = fd->private_data;
484 if ((status = get_ready_ep (fd->f_flags, data)) < 0)
487 spin_lock_irq (&data->dev->lock);
488 if (likely (data->ep != NULL)) {
490 case GADGETFS_FIFO_STATUS:
491 status = usb_ep_fifo_status (data->ep);
493 case GADGETFS_FIFO_FLUSH:
494 usb_ep_fifo_flush (data->ep);
496 case GADGETFS_CLEAR_HALT:
497 status = usb_ep_clear_halt (data->ep);
504 spin_unlock_irq (&data->dev->lock);
505 mutex_unlock(&data->lock);
509 /*----------------------------------------------------------------------*/
511 /* ASYNCHRONOUS ENDPOINT I/O OPERATIONS (bulk/intr/iso) */
514 struct usb_request *req;
515 struct ep_data *epdata;
517 struct mm_struct *mm;
518 struct work_struct work;
520 const struct iovec *iv;
521 unsigned long nr_segs;
525 static int ep_aio_cancel(struct kiocb *iocb)
527 struct kiocb_priv *priv = iocb->private;
528 struct ep_data *epdata;
532 epdata = priv->epdata;
533 // spin_lock(&epdata->dev->lock);
534 if (likely(epdata && epdata->ep && priv->req))
535 value = usb_ep_dequeue (epdata->ep, priv->req);
538 // spin_unlock(&epdata->dev->lock);
544 static ssize_t ep_copy_to_user(struct kiocb_priv *priv)
550 /* copy stuff into user buffers */
551 total = priv->actual;
554 for (i=0; i < priv->nr_segs; i++) {
555 ssize_t this = min((ssize_t)(priv->iv[i].iov_len), total);
557 if (copy_to_user(priv->iv[i].iov_base, to_copy, this)) {
573 static void ep_user_copy_worker(struct work_struct *work)
575 struct kiocb_priv *priv = container_of(work, struct kiocb_priv, work);
576 struct mm_struct *mm = priv->mm;
577 struct kiocb *iocb = priv->iocb;
581 ret = ep_copy_to_user(priv);
584 /* completing the iocb can drop the ctx and mm, don't touch mm after */
585 aio_complete(iocb, ret, ret);
591 static void ep_aio_complete(struct usb_ep *ep, struct usb_request *req)
593 struct kiocb *iocb = req->context;
594 struct kiocb_priv *priv = iocb->private;
595 struct ep_data *epdata = priv->epdata;
597 /* lock against disconnect (and ideally, cancel) */
598 spin_lock(&epdata->dev->lock);
602 /* if this was a write or a read returning no data then we
603 * don't need to copy anything to userspace, so we can
604 * complete the aio request immediately.
606 if (priv->iv == NULL || unlikely(req->actual == 0)) {
609 iocb->private = NULL;
610 /* aio_complete() reports bytes-transferred _and_ faults */
611 aio_complete(iocb, req->actual ? req->actual : req->status,
614 /* ep_copy_to_user() won't report both; we hide some faults */
615 if (unlikely(0 != req->status))
616 DBG(epdata->dev, "%s fault %d len %d\n",
617 ep->name, req->status, req->actual);
619 priv->buf = req->buf;
620 priv->actual = req->actual;
621 schedule_work(&priv->work);
623 spin_unlock(&epdata->dev->lock);
625 usb_ep_free_request(ep, req);
634 struct ep_data *epdata,
635 const struct iovec *iv,
636 unsigned long nr_segs
639 struct kiocb_priv *priv;
640 struct usb_request *req;
643 priv = kmalloc(sizeof *priv, GFP_KERNEL);
650 iocb->private = priv;
653 priv->nr_segs = nr_segs;
654 INIT_WORK(&priv->work, ep_user_copy_worker);
656 value = get_ready_ep(iocb->ki_filp->f_flags, epdata);
657 if (unlikely(value < 0)) {
662 kiocb_set_cancel_fn(iocb, ep_aio_cancel);
664 priv->epdata = epdata;
666 priv->mm = current->mm; /* mm teardown waits for iocbs in exit_aio() */
668 /* each kiocb is coupled to one usb_request, but we can't
669 * allocate or submit those if the host disconnected.
671 spin_lock_irq(&epdata->dev->lock);
672 if (likely(epdata->ep)) {
673 req = usb_ep_alloc_request(epdata->ep, GFP_ATOMIC);
678 req->complete = ep_aio_complete;
680 value = usb_ep_queue(epdata->ep, req, GFP_ATOMIC);
681 if (unlikely(0 != value))
682 usb_ep_free_request(epdata->ep, req);
687 spin_unlock_irq(&epdata->dev->lock);
689 mutex_unlock(&epdata->lock);
691 if (unlikely(value)) {
695 value = -EIOCBQUEUED;
700 ep_aio_read(struct kiocb *iocb, const struct iovec *iov,
701 unsigned long nr_segs, loff_t o)
703 struct ep_data *epdata = iocb->ki_filp->private_data;
706 if (unlikely(usb_endpoint_dir_in(&epdata->desc)))
709 buf = kmalloc(iocb->ki_nbytes, GFP_KERNEL);
713 return ep_aio_rwtail(iocb, buf, iocb->ki_nbytes, epdata, iov, nr_segs);
717 ep_aio_write(struct kiocb *iocb, const struct iovec *iov,
718 unsigned long nr_segs, loff_t o)
720 struct ep_data *epdata = iocb->ki_filp->private_data;
725 if (unlikely(!usb_endpoint_dir_in(&epdata->desc)))
728 buf = kmalloc(iocb->ki_nbytes, GFP_KERNEL);
732 for (i=0; i < nr_segs; i++) {
733 if (unlikely(copy_from_user(&buf[len], iov[i].iov_base,
734 iov[i].iov_len) != 0)) {
738 len += iov[i].iov_len;
740 return ep_aio_rwtail(iocb, buf, len, epdata, NULL, 0);
743 /*----------------------------------------------------------------------*/
745 /* used after endpoint configuration */
746 static const struct file_operations ep_io_operations = {
747 .owner = THIS_MODULE,
752 .unlocked_ioctl = ep_ioctl,
753 .release = ep_release,
755 .aio_read = ep_aio_read,
756 .aio_write = ep_aio_write,
759 /* ENDPOINT INITIALIZATION
761 * fd = open ("/dev/gadget/$ENDPOINT", O_RDWR)
762 * status = write (fd, descriptors, sizeof descriptors)
764 * That write establishes the endpoint configuration, configuring
765 * the controller to process bulk, interrupt, or isochronous transfers
766 * at the right maxpacket size, and so on.
768 * The descriptors are message type 1, identified by a host order u32
769 * at the beginning of what's written. Descriptor order is: full/low
770 * speed descriptor, then optional high speed descriptor.
773 ep_config (struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
775 struct ep_data *data = fd->private_data;
778 int value, length = len;
780 value = mutex_lock_interruptible(&data->lock);
784 if (data->state != STATE_EP_READY) {
790 if (len < USB_DT_ENDPOINT_SIZE + 4)
793 /* we might need to change message format someday */
794 if (copy_from_user (&tag, buf, 4)) {
798 DBG(data->dev, "config %s, bad tag %d\n", data->name, tag);
804 /* NOTE: audio endpoint extensions not accepted here;
805 * just don't include the extra bytes.
808 /* full/low speed descriptor, then high speed */
809 if (copy_from_user (&data->desc, buf, USB_DT_ENDPOINT_SIZE)) {
812 if (data->desc.bLength != USB_DT_ENDPOINT_SIZE
813 || data->desc.bDescriptorType != USB_DT_ENDPOINT)
815 if (len != USB_DT_ENDPOINT_SIZE) {
816 if (len != 2 * USB_DT_ENDPOINT_SIZE)
818 if (copy_from_user (&data->hs_desc, buf + USB_DT_ENDPOINT_SIZE,
819 USB_DT_ENDPOINT_SIZE)) {
822 if (data->hs_desc.bLength != USB_DT_ENDPOINT_SIZE
823 || data->hs_desc.bDescriptorType
824 != USB_DT_ENDPOINT) {
825 DBG(data->dev, "config %s, bad hs length or type\n",
831 spin_lock_irq (&data->dev->lock);
832 if (data->dev->state == STATE_DEV_UNBOUND) {
835 } else if ((ep = data->ep) == NULL) {
839 switch (data->dev->gadget->speed) {
842 ep->desc = &data->desc;
843 value = usb_ep_enable(ep);
845 data->state = STATE_EP_ENABLED;
848 /* fails if caller didn't provide that descriptor... */
849 ep->desc = &data->hs_desc;
850 value = usb_ep_enable(ep);
852 data->state = STATE_EP_ENABLED;
855 DBG(data->dev, "unconnected, %s init abandoned\n",
860 fd->f_op = &ep_io_operations;
864 spin_unlock_irq (&data->dev->lock);
867 data->desc.bDescriptorType = 0;
868 data->hs_desc.bDescriptorType = 0;
870 mutex_unlock(&data->lock);
881 ep_open (struct inode *inode, struct file *fd)
883 struct ep_data *data = inode->i_private;
886 if (mutex_lock_interruptible(&data->lock) != 0)
888 spin_lock_irq (&data->dev->lock);
889 if (data->dev->state == STATE_DEV_UNBOUND)
891 else if (data->state == STATE_EP_DISABLED) {
893 data->state = STATE_EP_READY;
895 fd->private_data = data;
896 VDEBUG (data->dev, "%s ready\n", data->name);
898 DBG (data->dev, "%s state %d\n",
899 data->name, data->state);
900 spin_unlock_irq (&data->dev->lock);
901 mutex_unlock(&data->lock);
905 /* used before endpoint configuration */
906 static const struct file_operations ep_config_operations = {
911 .release = ep_release,
914 /*----------------------------------------------------------------------*/
916 /* EP0 IMPLEMENTATION can be partly in userspace.
918 * Drivers that use this facility receive various events, including
919 * control requests the kernel doesn't handle. Drivers that don't
920 * use this facility may be too simple-minded for real applications.
923 static inline void ep0_readable (struct dev_data *dev)
925 wake_up (&dev->wait);
926 kill_fasync (&dev->fasync, SIGIO, POLL_IN);
929 static void clean_req (struct usb_ep *ep, struct usb_request *req)
931 struct dev_data *dev = ep->driver_data;
933 if (req->buf != dev->rbuf) {
935 req->buf = dev->rbuf;
937 req->complete = epio_complete;
938 dev->setup_out_ready = 0;
941 static void ep0_complete (struct usb_ep *ep, struct usb_request *req)
943 struct dev_data *dev = ep->driver_data;
947 /* for control OUT, data must still get to userspace */
948 spin_lock_irqsave(&dev->lock, flags);
949 if (!dev->setup_in) {
950 dev->setup_out_error = (req->status != 0);
951 if (!dev->setup_out_error)
953 dev->setup_out_ready = 1;
957 /* clean up as appropriate */
958 if (free && req->buf != &dev->rbuf)
960 req->complete = epio_complete;
961 spin_unlock_irqrestore(&dev->lock, flags);
964 static int setup_req (struct usb_ep *ep, struct usb_request *req, u16 len)
966 struct dev_data *dev = ep->driver_data;
968 if (dev->setup_out_ready) {
969 DBG (dev, "ep0 request busy!\n");
972 if (len > sizeof (dev->rbuf))
973 req->buf = kmalloc(len, GFP_ATOMIC);
974 if (req->buf == NULL) {
975 req->buf = dev->rbuf;
978 req->complete = ep0_complete;
985 ep0_read (struct file *fd, char __user *buf, size_t len, loff_t *ptr)
987 struct dev_data *dev = fd->private_data;
989 enum ep0_state state;
991 spin_lock_irq (&dev->lock);
993 /* report fd mode change before acting on it */
994 if (dev->setup_abort) {
995 dev->setup_abort = 0;
1000 /* control DATA stage */
1001 if ((state = dev->state) == STATE_DEV_SETUP) {
1003 if (dev->setup_in) { /* stall IN */
1004 VDEBUG(dev, "ep0in stall\n");
1005 (void) usb_ep_set_halt (dev->gadget->ep0);
1007 dev->state = STATE_DEV_CONNECTED;
1009 } else if (len == 0) { /* ack SET_CONFIGURATION etc */
1010 struct usb_ep *ep = dev->gadget->ep0;
1011 struct usb_request *req = dev->req;
1013 if ((retval = setup_req (ep, req, 0)) == 0)
1014 retval = usb_ep_queue (ep, req, GFP_ATOMIC);
1015 dev->state = STATE_DEV_CONNECTED;
1017 /* assume that was SET_CONFIGURATION */
1018 if (dev->current_config) {
1021 if (gadget_is_dualspeed(dev->gadget)
1022 && (dev->gadget->speed
1024 power = dev->hs_config->bMaxPower;
1026 power = dev->config->bMaxPower;
1027 usb_gadget_vbus_draw(dev->gadget, 2 * power);
1030 } else { /* collect OUT data */
1031 if ((fd->f_flags & O_NONBLOCK) != 0
1032 && !dev->setup_out_ready) {
1036 spin_unlock_irq (&dev->lock);
1037 retval = wait_event_interruptible (dev->wait,
1038 dev->setup_out_ready != 0);
1040 /* FIXME state could change from under us */
1041 spin_lock_irq (&dev->lock);
1045 if (dev->state != STATE_DEV_SETUP) {
1046 retval = -ECANCELED;
1049 dev->state = STATE_DEV_CONNECTED;
1051 if (dev->setup_out_error)
1054 len = min (len, (size_t)dev->req->actual);
1055 // FIXME don't call this with the spinlock held ...
1056 if (copy_to_user (buf, dev->req->buf, len))
1060 clean_req (dev->gadget->ep0, dev->req);
1061 /* NOTE userspace can't yet choose to stall */
1067 /* else normal: return event data */
1068 if (len < sizeof dev->event [0]) {
1072 len -= len % sizeof (struct usb_gadgetfs_event);
1073 dev->usermode_setup = 1;
1076 /* return queued events right away */
1077 if (dev->ev_next != 0) {
1080 n = len / sizeof (struct usb_gadgetfs_event);
1081 if (dev->ev_next < n)
1084 /* ep0 i/o has special semantics during STATE_DEV_SETUP */
1085 for (i = 0; i < n; i++) {
1086 if (dev->event [i].type == GADGETFS_SETUP) {
1087 dev->state = STATE_DEV_SETUP;
1092 spin_unlock_irq (&dev->lock);
1093 len = n * sizeof (struct usb_gadgetfs_event);
1094 if (copy_to_user (buf, &dev->event, len))
1099 /* NOTE this doesn't guard against broken drivers;
1100 * concurrent ep0 readers may lose events.
1102 spin_lock_irq (&dev->lock);
1103 if (dev->ev_next > n) {
1104 memmove(&dev->event[0], &dev->event[n],
1105 sizeof (struct usb_gadgetfs_event)
1106 * (dev->ev_next - n));
1109 spin_unlock_irq (&dev->lock);
1113 if (fd->f_flags & O_NONBLOCK) {
1120 DBG (dev, "fail %s, state %d\n", __func__, state);
1123 case STATE_DEV_UNCONNECTED:
1124 case STATE_DEV_CONNECTED:
1125 spin_unlock_irq (&dev->lock);
1126 DBG (dev, "%s wait\n", __func__);
1128 /* wait for events */
1129 retval = wait_event_interruptible (dev->wait,
1133 spin_lock_irq (&dev->lock);
1138 spin_unlock_irq (&dev->lock);
1142 static struct usb_gadgetfs_event *
1143 next_event (struct dev_data *dev, enum usb_gadgetfs_event_type type)
1145 struct usb_gadgetfs_event *event;
1149 /* these events purge the queue */
1150 case GADGETFS_DISCONNECT:
1151 if (dev->state == STATE_DEV_SETUP)
1152 dev->setup_abort = 1;
1154 case GADGETFS_CONNECT:
1157 case GADGETFS_SETUP: /* previous request timed out */
1158 case GADGETFS_SUSPEND: /* same effect */
1159 /* these events can't be repeated */
1160 for (i = 0; i != dev->ev_next; i++) {
1161 if (dev->event [i].type != type)
1163 DBG(dev, "discard old event[%d] %d\n", i, type);
1165 if (i == dev->ev_next)
1167 /* indices start at zero, for simplicity */
1168 memmove (&dev->event [i], &dev->event [i + 1],
1169 sizeof (struct usb_gadgetfs_event)
1170 * (dev->ev_next - i));
1176 VDEBUG(dev, "event[%d] = %d\n", dev->ev_next, type);
1177 event = &dev->event [dev->ev_next++];
1178 BUG_ON (dev->ev_next > N_EVENT);
1179 memset (event, 0, sizeof *event);
1185 ep0_write (struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
1187 struct dev_data *dev = fd->private_data;
1188 ssize_t retval = -ESRCH;
1190 spin_lock_irq (&dev->lock);
1192 /* report fd mode change before acting on it */
1193 if (dev->setup_abort) {
1194 dev->setup_abort = 0;
1197 /* data and/or status stage for control request */
1198 } else if (dev->state == STATE_DEV_SETUP) {
1200 /* IN DATA+STATUS caller makes len <= wLength */
1201 if (dev->setup_in) {
1202 retval = setup_req (dev->gadget->ep0, dev->req, len);
1204 dev->state = STATE_DEV_CONNECTED;
1205 spin_unlock_irq (&dev->lock);
1206 if (copy_from_user (dev->req->buf, buf, len))
1209 if (len < dev->setup_wLength)
1211 retval = usb_ep_queue (
1212 dev->gadget->ep0, dev->req,
1216 spin_lock_irq (&dev->lock);
1217 clean_req (dev->gadget->ep0, dev->req);
1218 spin_unlock_irq (&dev->lock);
1225 /* can stall some OUT transfers */
1226 } else if (dev->setup_can_stall) {
1227 VDEBUG(dev, "ep0out stall\n");
1228 (void) usb_ep_set_halt (dev->gadget->ep0);
1230 dev->state = STATE_DEV_CONNECTED;
1232 DBG(dev, "bogus ep0out stall!\n");
1235 DBG (dev, "fail %s, state %d\n", __func__, dev->state);
1237 spin_unlock_irq (&dev->lock);
1242 ep0_fasync (int f, struct file *fd, int on)
1244 struct dev_data *dev = fd->private_data;
1245 // caller must F_SETOWN before signal delivery happens
1246 VDEBUG (dev, "%s %s\n", __func__, on ? "on" : "off");
1247 return fasync_helper (f, fd, on, &dev->fasync);
1250 static struct usb_gadget_driver gadgetfs_driver;
1253 dev_release (struct inode *inode, struct file *fd)
1255 struct dev_data *dev = fd->private_data;
1257 /* closing ep0 === shutdown all */
1259 usb_gadget_unregister_driver (&gadgetfs_driver);
1261 /* at this point "good" hardware has disconnected the
1262 * device from USB; the host won't see it any more.
1263 * alternatively, all host requests will time out.
1269 /* other endpoints were all decoupled from this device */
1270 spin_lock_irq(&dev->lock);
1271 dev->state = STATE_DEV_DISABLED;
1272 spin_unlock_irq(&dev->lock);
1279 ep0_poll (struct file *fd, poll_table *wait)
1281 struct dev_data *dev = fd->private_data;
1284 poll_wait(fd, &dev->wait, wait);
1286 spin_lock_irq (&dev->lock);
1288 /* report fd mode change before acting on it */
1289 if (dev->setup_abort) {
1290 dev->setup_abort = 0;
1295 if (dev->state == STATE_DEV_SETUP) {
1296 if (dev->setup_in || dev->setup_can_stall)
1299 if (dev->ev_next != 0)
1303 spin_unlock_irq(&dev->lock);
1307 static long dev_ioctl (struct file *fd, unsigned code, unsigned long value)
1309 struct dev_data *dev = fd->private_data;
1310 struct usb_gadget *gadget = dev->gadget;
1313 if (gadget->ops->ioctl)
1314 ret = gadget->ops->ioctl (gadget, code, value);
1319 /* used after device configuration */
1320 static const struct file_operations ep0_io_operations = {
1321 .owner = THIS_MODULE,
1322 .llseek = no_llseek,
1326 .fasync = ep0_fasync,
1328 .unlocked_ioctl = dev_ioctl,
1329 .release = dev_release,
1332 /*----------------------------------------------------------------------*/
1334 /* The in-kernel gadget driver handles most ep0 issues, in particular
1335 * enumerating the single configuration (as provided from user space).
1337 * Unrecognized ep0 requests may be handled in user space.
1340 static void make_qualifier (struct dev_data *dev)
1342 struct usb_qualifier_descriptor qual;
1343 struct usb_device_descriptor *desc;
1345 qual.bLength = sizeof qual;
1346 qual.bDescriptorType = USB_DT_DEVICE_QUALIFIER;
1347 qual.bcdUSB = cpu_to_le16 (0x0200);
1350 qual.bDeviceClass = desc->bDeviceClass;
1351 qual.bDeviceSubClass = desc->bDeviceSubClass;
1352 qual.bDeviceProtocol = desc->bDeviceProtocol;
1354 /* assumes ep0 uses the same value for both speeds ... */
1355 qual.bMaxPacketSize0 = dev->gadget->ep0->maxpacket;
1357 qual.bNumConfigurations = 1;
1360 memcpy (dev->rbuf, &qual, sizeof qual);
1364 config_buf (struct dev_data *dev, u8 type, unsigned index)
1369 /* only one configuration */
1373 if (gadget_is_dualspeed(dev->gadget)) {
1374 hs = (dev->gadget->speed == USB_SPEED_HIGH);
1375 if (type == USB_DT_OTHER_SPEED_CONFIG)
1379 dev->req->buf = dev->hs_config;
1380 len = le16_to_cpu(dev->hs_config->wTotalLength);
1382 dev->req->buf = dev->config;
1383 len = le16_to_cpu(dev->config->wTotalLength);
1385 ((u8 *)dev->req->buf) [1] = type;
1390 gadgetfs_setup (struct usb_gadget *gadget, const struct usb_ctrlrequest *ctrl)
1392 struct dev_data *dev = get_gadget_data (gadget);
1393 struct usb_request *req = dev->req;
1394 int value = -EOPNOTSUPP;
1395 struct usb_gadgetfs_event *event;
1396 u16 w_value = le16_to_cpu(ctrl->wValue);
1397 u16 w_length = le16_to_cpu(ctrl->wLength);
1399 spin_lock (&dev->lock);
1400 dev->setup_abort = 0;
1401 if (dev->state == STATE_DEV_UNCONNECTED) {
1402 if (gadget_is_dualspeed(gadget)
1403 && gadget->speed == USB_SPEED_HIGH
1404 && dev->hs_config == NULL) {
1405 spin_unlock(&dev->lock);
1406 ERROR (dev, "no high speed config??\n");
1410 dev->state = STATE_DEV_CONNECTED;
1412 INFO (dev, "connected\n");
1413 event = next_event (dev, GADGETFS_CONNECT);
1414 event->u.speed = gadget->speed;
1417 /* host may have given up waiting for response. we can miss control
1418 * requests handled lower down (device/endpoint status and features);
1419 * then ep0_{read,write} will report the wrong status. controller
1420 * driver will have aborted pending i/o.
1422 } else if (dev->state == STATE_DEV_SETUP)
1423 dev->setup_abort = 1;
1425 req->buf = dev->rbuf;
1426 req->context = NULL;
1427 value = -EOPNOTSUPP;
1428 switch (ctrl->bRequest) {
1430 case USB_REQ_GET_DESCRIPTOR:
1431 if (ctrl->bRequestType != USB_DIR_IN)
1433 switch (w_value >> 8) {
1436 value = min (w_length, (u16) sizeof *dev->dev);
1437 dev->dev->bMaxPacketSize0 = dev->gadget->ep0->maxpacket;
1438 req->buf = dev->dev;
1440 case USB_DT_DEVICE_QUALIFIER:
1441 if (!dev->hs_config)
1443 value = min (w_length, (u16)
1444 sizeof (struct usb_qualifier_descriptor));
1445 make_qualifier (dev);
1447 case USB_DT_OTHER_SPEED_CONFIG:
1450 value = config_buf (dev,
1454 value = min (w_length, (u16) value);
1459 default: // all others are errors
1464 /* currently one config, two speeds */
1465 case USB_REQ_SET_CONFIGURATION:
1466 if (ctrl->bRequestType != 0)
1468 if (0 == (u8) w_value) {
1470 dev->current_config = 0;
1471 usb_gadget_vbus_draw(gadget, 8 /* mA */ );
1472 // user mode expected to disable endpoints
1476 if (gadget_is_dualspeed(gadget)
1477 && gadget->speed == USB_SPEED_HIGH) {
1478 config = dev->hs_config->bConfigurationValue;
1479 power = dev->hs_config->bMaxPower;
1481 config = dev->config->bConfigurationValue;
1482 power = dev->config->bMaxPower;
1485 if (config == (u8) w_value) {
1487 dev->current_config = config;
1488 usb_gadget_vbus_draw(gadget, 2 * power);
1492 /* report SET_CONFIGURATION like any other control request,
1493 * except that usermode may not stall this. the next
1494 * request mustn't be allowed start until this finishes:
1495 * endpoints and threads set up, etc.
1497 * NOTE: older PXA hardware (before PXA 255: without UDCCFR)
1498 * has bad/racey automagic that prevents synchronizing here.
1499 * even kernel mode drivers often miss them.
1502 INFO (dev, "configuration #%d\n", dev->current_config);
1503 usb_gadget_set_state(gadget, USB_STATE_CONFIGURED);
1504 if (dev->usermode_setup) {
1505 dev->setup_can_stall = 0;
1511 #ifndef CONFIG_USB_PXA25X
1512 /* PXA automagically handles this request too */
1513 case USB_REQ_GET_CONFIGURATION:
1514 if (ctrl->bRequestType != 0x80)
1516 *(u8 *)req->buf = dev->current_config;
1517 value = min (w_length, (u16) 1);
1523 VDEBUG (dev, "%s req%02x.%02x v%04x i%04x l%d\n",
1524 dev->usermode_setup ? "delegate" : "fail",
1525 ctrl->bRequestType, ctrl->bRequest,
1526 w_value, le16_to_cpu(ctrl->wIndex), w_length);
1528 /* if there's an ep0 reader, don't stall */
1529 if (dev->usermode_setup) {
1530 dev->setup_can_stall = 1;
1532 dev->setup_in = (ctrl->bRequestType & USB_DIR_IN)
1534 dev->setup_wLength = w_length;
1535 dev->setup_out_ready = 0;
1536 dev->setup_out_error = 0;
1539 /* read DATA stage for OUT right away */
1540 if (unlikely (!dev->setup_in && w_length)) {
1541 value = setup_req (gadget->ep0, dev->req,
1545 value = usb_ep_queue (gadget->ep0, dev->req,
1548 clean_req (gadget->ep0, dev->req);
1552 /* we can't currently stall these */
1553 dev->setup_can_stall = 0;
1556 /* state changes when reader collects event */
1557 event = next_event (dev, GADGETFS_SETUP);
1558 event->u.setup = *ctrl;
1560 spin_unlock (&dev->lock);
1565 /* proceed with data transfer and status phases? */
1566 if (value >= 0 && dev->state != STATE_DEV_SETUP) {
1567 req->length = value;
1568 req->zero = value < w_length;
1569 value = usb_ep_queue (gadget->ep0, req, GFP_ATOMIC);
1571 DBG (dev, "ep_queue --> %d\n", value);
1576 /* device stalls when value < 0 */
1577 spin_unlock (&dev->lock);
1581 static void destroy_ep_files (struct dev_data *dev)
1583 DBG (dev, "%s %d\n", __func__, dev->state);
1585 /* dev->state must prevent interference */
1586 spin_lock_irq (&dev->lock);
1587 while (!list_empty(&dev->epfiles)) {
1589 struct inode *parent;
1590 struct dentry *dentry;
1592 /* break link to FS */
1593 ep = list_first_entry (&dev->epfiles, struct ep_data, epfiles);
1594 list_del_init (&ep->epfiles);
1595 dentry = ep->dentry;
1597 parent = dentry->d_parent->d_inode;
1599 /* break link to controller */
1600 if (ep->state == STATE_EP_ENABLED)
1601 (void) usb_ep_disable (ep->ep);
1602 ep->state = STATE_EP_UNBOUND;
1603 usb_ep_free_request (ep->ep, ep->req);
1605 wake_up (&ep->wait);
1608 spin_unlock_irq (&dev->lock);
1610 /* break link to dcache */
1611 mutex_lock (&parent->i_mutex);
1614 mutex_unlock (&parent->i_mutex);
1616 spin_lock_irq (&dev->lock);
1618 spin_unlock_irq (&dev->lock);
1622 static struct dentry *
1623 gadgetfs_create_file (struct super_block *sb, char const *name,
1624 void *data, const struct file_operations *fops);
1626 static int activate_ep_files (struct dev_data *dev)
1629 struct ep_data *data;
1631 gadget_for_each_ep (ep, dev->gadget) {
1633 data = kzalloc(sizeof(*data), GFP_KERNEL);
1636 data->state = STATE_EP_DISABLED;
1637 mutex_init(&data->lock);
1638 init_waitqueue_head (&data->wait);
1640 strncpy (data->name, ep->name, sizeof (data->name) - 1);
1641 atomic_set (&data->count, 1);
1646 ep->driver_data = data;
1648 data->req = usb_ep_alloc_request (ep, GFP_KERNEL);
1652 data->dentry = gadgetfs_create_file (dev->sb, data->name,
1653 data, &ep_config_operations);
1656 list_add_tail (&data->epfiles, &dev->epfiles);
1661 usb_ep_free_request (ep, data->req);
1666 DBG (dev, "%s enomem\n", __func__);
1667 destroy_ep_files (dev);
1672 gadgetfs_unbind (struct usb_gadget *gadget)
1674 struct dev_data *dev = get_gadget_data (gadget);
1676 DBG (dev, "%s\n", __func__);
1678 spin_lock_irq (&dev->lock);
1679 dev->state = STATE_DEV_UNBOUND;
1680 spin_unlock_irq (&dev->lock);
1682 destroy_ep_files (dev);
1683 gadget->ep0->driver_data = NULL;
1684 set_gadget_data (gadget, NULL);
1686 /* we've already been disconnected ... no i/o is active */
1688 usb_ep_free_request (gadget->ep0, dev->req);
1689 DBG (dev, "%s done\n", __func__);
1693 static struct dev_data *the_device;
1695 static int gadgetfs_bind(struct usb_gadget *gadget,
1696 struct usb_gadget_driver *driver)
1698 struct dev_data *dev = the_device;
1702 if (0 != strcmp (CHIP, gadget->name)) {
1703 pr_err("%s expected %s controller not %s\n",
1704 shortname, CHIP, gadget->name);
1708 set_gadget_data (gadget, dev);
1709 dev->gadget = gadget;
1710 gadget->ep0->driver_data = dev;
1712 /* preallocate control response and buffer */
1713 dev->req = usb_ep_alloc_request (gadget->ep0, GFP_KERNEL);
1716 dev->req->context = NULL;
1717 dev->req->complete = epio_complete;
1719 if (activate_ep_files (dev) < 0)
1722 INFO (dev, "bound to %s driver\n", gadget->name);
1723 spin_lock_irq(&dev->lock);
1724 dev->state = STATE_DEV_UNCONNECTED;
1725 spin_unlock_irq(&dev->lock);
1730 gadgetfs_unbind (gadget);
1735 gadgetfs_disconnect (struct usb_gadget *gadget)
1737 struct dev_data *dev = get_gadget_data (gadget);
1738 unsigned long flags;
1740 spin_lock_irqsave (&dev->lock, flags);
1741 if (dev->state == STATE_DEV_UNCONNECTED)
1743 dev->state = STATE_DEV_UNCONNECTED;
1745 INFO (dev, "disconnected\n");
1746 next_event (dev, GADGETFS_DISCONNECT);
1749 spin_unlock_irqrestore (&dev->lock, flags);
1753 gadgetfs_suspend (struct usb_gadget *gadget)
1755 struct dev_data *dev = get_gadget_data (gadget);
1757 INFO (dev, "suspended from state %d\n", dev->state);
1758 spin_lock (&dev->lock);
1759 switch (dev->state) {
1760 case STATE_DEV_SETUP: // VERY odd... host died??
1761 case STATE_DEV_CONNECTED:
1762 case STATE_DEV_UNCONNECTED:
1763 next_event (dev, GADGETFS_SUSPEND);
1769 spin_unlock (&dev->lock);
1772 static struct usb_gadget_driver gadgetfs_driver = {
1773 .function = (char *) driver_desc,
1774 .bind = gadgetfs_bind,
1775 .unbind = gadgetfs_unbind,
1776 .setup = gadgetfs_setup,
1777 .reset = gadgetfs_disconnect,
1778 .disconnect = gadgetfs_disconnect,
1779 .suspend = gadgetfs_suspend,
1782 .name = (char *) shortname,
1786 /*----------------------------------------------------------------------*/
1788 static void gadgetfs_nop(struct usb_gadget *arg) { }
1790 static int gadgetfs_probe(struct usb_gadget *gadget,
1791 struct usb_gadget_driver *driver)
1793 CHIP = gadget->name;
1797 static struct usb_gadget_driver probe_driver = {
1798 .max_speed = USB_SPEED_HIGH,
1799 .bind = gadgetfs_probe,
1800 .unbind = gadgetfs_nop,
1801 .setup = (void *)gadgetfs_nop,
1802 .disconnect = gadgetfs_nop,
1809 /* DEVICE INITIALIZATION
1811 * fd = open ("/dev/gadget/$CHIP", O_RDWR)
1812 * status = write (fd, descriptors, sizeof descriptors)
1814 * That write establishes the device configuration, so the kernel can
1815 * bind to the controller ... guaranteeing it can handle enumeration
1816 * at all necessary speeds. Descriptor order is:
1818 * . message tag (u32, host order) ... for now, must be zero; it
1819 * would change to support features like multi-config devices
1820 * . full/low speed config ... all wTotalLength bytes (with interface,
1821 * class, altsetting, endpoint, and other descriptors)
1822 * . high speed config ... all descriptors, for high speed operation;
1823 * this one's optional except for high-speed hardware
1824 * . device descriptor
1826 * Endpoints are not yet enabled. Drivers must wait until device
1827 * configuration and interface altsetting changes create
1828 * the need to configure (or unconfigure) them.
1830 * After initialization, the device stays active for as long as that
1831 * $CHIP file is open. Events must then be read from that descriptor,
1832 * such as configuration notifications.
1835 static int is_valid_config (struct usb_config_descriptor *config)
1837 return config->bDescriptorType == USB_DT_CONFIG
1838 && config->bLength == USB_DT_CONFIG_SIZE
1839 && config->bConfigurationValue != 0
1840 && (config->bmAttributes & USB_CONFIG_ATT_ONE) != 0
1841 && (config->bmAttributes & USB_CONFIG_ATT_WAKEUP) == 0;
1842 /* FIXME if gadget->is_otg, _must_ include an otg descriptor */
1843 /* FIXME check lengths: walk to end */
1847 dev_config (struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
1849 struct dev_data *dev = fd->private_data;
1850 ssize_t value = len, length = len;
1855 if (len < (USB_DT_CONFIG_SIZE + USB_DT_DEVICE_SIZE + 4))
1858 /* we might need to change message format someday */
1859 if (copy_from_user (&tag, buf, 4))
1866 kbuf = memdup_user(buf, length);
1868 return PTR_ERR(kbuf);
1870 spin_lock_irq (&dev->lock);
1876 /* full or low speed config */
1877 dev->config = (void *) kbuf;
1878 total = le16_to_cpu(dev->config->wTotalLength);
1879 if (!is_valid_config (dev->config) || total >= length)
1884 /* optional high speed config */
1885 if (kbuf [1] == USB_DT_CONFIG) {
1886 dev->hs_config = (void *) kbuf;
1887 total = le16_to_cpu(dev->hs_config->wTotalLength);
1888 if (!is_valid_config (dev->hs_config) || total >= length)
1894 /* could support multiple configs, using another encoding! */
1896 /* device descriptor (tweaked for paranoia) */
1897 if (length != USB_DT_DEVICE_SIZE)
1899 dev->dev = (void *)kbuf;
1900 if (dev->dev->bLength != USB_DT_DEVICE_SIZE
1901 || dev->dev->bDescriptorType != USB_DT_DEVICE
1902 || dev->dev->bNumConfigurations != 1)
1904 dev->dev->bNumConfigurations = 1;
1905 dev->dev->bcdUSB = cpu_to_le16 (0x0200);
1907 /* triggers gadgetfs_bind(); then we can enumerate. */
1908 spin_unlock_irq (&dev->lock);
1910 gadgetfs_driver.max_speed = USB_SPEED_HIGH;
1912 gadgetfs_driver.max_speed = USB_SPEED_FULL;
1914 value = usb_gadget_probe_driver(&gadgetfs_driver);
1919 /* at this point "good" hardware has for the first time
1920 * let the USB the host see us. alternatively, if users
1921 * unplug/replug that will clear all the error state.
1923 * note: everything running before here was guaranteed
1924 * to choke driver model style diagnostics. from here
1925 * on, they can work ... except in cleanup paths that
1926 * kick in after the ep0 descriptor is closed.
1928 fd->f_op = &ep0_io_operations;
1934 spin_unlock_irq (&dev->lock);
1935 pr_debug ("%s: %s fail %Zd, %p\n", shortname, __func__, value, dev);
1942 dev_open (struct inode *inode, struct file *fd)
1944 struct dev_data *dev = inode->i_private;
1947 spin_lock_irq(&dev->lock);
1948 if (dev->state == STATE_DEV_DISABLED) {
1950 dev->state = STATE_DEV_OPENED;
1951 fd->private_data = dev;
1955 spin_unlock_irq(&dev->lock);
1959 static const struct file_operations dev_init_operations = {
1960 .llseek = no_llseek,
1963 .write = dev_config,
1964 .fasync = ep0_fasync,
1965 .unlocked_ioctl = dev_ioctl,
1966 .release = dev_release,
1969 /*----------------------------------------------------------------------*/
1971 /* FILESYSTEM AND SUPERBLOCK OPERATIONS
1973 * Mounting the filesystem creates a controller file, used first for
1974 * device configuration then later for event monitoring.
1978 /* FIXME PAM etc could set this security policy without mount options
1979 * if epfiles inherited ownership and permissons from ep0 ...
1982 static unsigned default_uid;
1983 static unsigned default_gid;
1984 static unsigned default_perm = S_IRUSR | S_IWUSR;
1986 module_param (default_uid, uint, 0644);
1987 module_param (default_gid, uint, 0644);
1988 module_param (default_perm, uint, 0644);
1991 static struct inode *
1992 gadgetfs_make_inode (struct super_block *sb,
1993 void *data, const struct file_operations *fops,
1996 struct inode *inode = new_inode (sb);
1999 inode->i_ino = get_next_ino();
2000 inode->i_mode = mode;
2001 inode->i_uid = make_kuid(&init_user_ns, default_uid);
2002 inode->i_gid = make_kgid(&init_user_ns, default_gid);
2003 inode->i_atime = inode->i_mtime = inode->i_ctime
2005 inode->i_private = data;
2006 inode->i_fop = fops;
2011 /* creates in fs root directory, so non-renamable and non-linkable.
2012 * so inode and dentry are paired, until device reconfig.
2014 static struct dentry *
2015 gadgetfs_create_file (struct super_block *sb, char const *name,
2016 void *data, const struct file_operations *fops)
2018 struct dentry *dentry;
2019 struct inode *inode;
2021 dentry = d_alloc_name(sb->s_root, name);
2025 inode = gadgetfs_make_inode (sb, data, fops,
2026 S_IFREG | (default_perm & S_IRWXUGO));
2031 d_add (dentry, inode);
2035 static const struct super_operations gadget_fs_operations = {
2036 .statfs = simple_statfs,
2037 .drop_inode = generic_delete_inode,
2041 gadgetfs_fill_super (struct super_block *sb, void *opts, int silent)
2043 struct inode *inode;
2044 struct dev_data *dev;
2049 /* fake probe to determine $CHIP */
2051 usb_gadget_probe_driver(&probe_driver);
2056 sb->s_blocksize = PAGE_CACHE_SIZE;
2057 sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
2058 sb->s_magic = GADGETFS_MAGIC;
2059 sb->s_op = &gadget_fs_operations;
2060 sb->s_time_gran = 1;
2063 inode = gadgetfs_make_inode (sb,
2064 NULL, &simple_dir_operations,
2065 S_IFDIR | S_IRUGO | S_IXUGO);
2068 inode->i_op = &simple_dir_inode_operations;
2069 if (!(sb->s_root = d_make_root (inode)))
2072 /* the ep0 file is named after the controller we expect;
2073 * user mode code can use it for sanity checks, like we do.
2080 dev->dentry = gadgetfs_create_file(sb, CHIP, dev, &dev_init_operations);
2086 /* other endpoint files are available after hardware setup,
2087 * from binding to a controller.
2096 /* "mount -t gadgetfs path /dev/gadget" ends up here */
2097 static struct dentry *
2098 gadgetfs_mount (struct file_system_type *t, int flags,
2099 const char *path, void *opts)
2101 return mount_single (t, flags, opts, gadgetfs_fill_super);
2105 gadgetfs_kill_sb (struct super_block *sb)
2107 kill_litter_super (sb);
2109 put_dev (the_device);
2114 /*----------------------------------------------------------------------*/
2116 static struct file_system_type gadgetfs_type = {
2117 .owner = THIS_MODULE,
2119 .mount = gadgetfs_mount,
2120 .kill_sb = gadgetfs_kill_sb,
2122 MODULE_ALIAS_FS("gadgetfs");
2124 /*----------------------------------------------------------------------*/
2126 static int __init init (void)
2130 status = register_filesystem (&gadgetfs_type);
2132 pr_info ("%s: %s, version " DRIVER_VERSION "\n",
2133 shortname, driver_desc);
2138 static void __exit cleanup (void)
2140 pr_debug ("unregister %s\n", shortname);
2141 unregister_filesystem (&gadgetfs_type);
2143 module_exit (cleanup);