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.
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
17 * You should have received a copy of the GNU General Public License
18 * along with this program; if not, write to the Free Software
19 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
23 /* #define VERBOSE_DEBUG */
25 #include <linux/init.h>
26 #include <linux/module.h>
28 #include <linux/pagemap.h>
29 #include <linux/uts.h>
30 #include <linux/wait.h>
31 #include <linux/compiler.h>
32 #include <asm/uaccess.h>
33 #include <linux/sched.h>
34 #include <linux/slab.h>
35 #include <linux/poll.h>
37 #include <linux/device.h>
38 #include <linux/moduleparam.h>
40 #include <linux/usb/gadgetfs.h>
41 #include <linux/usb/gadget.h>
45 * The gadgetfs API maps each endpoint to a file descriptor so that you
46 * can use standard synchronous read/write calls for I/O. There's some
47 * O_NONBLOCK and O_ASYNC/FASYNC style i/o support. Example usermode
48 * drivers show how this works in practice. You can also use AIO to
49 * eliminate I/O gaps between requests, to help when streaming data.
51 * Key parts that must be USB-specific are protocols defining how the
52 * read/write operations relate to the hardware state machines. There
53 * are two types of files. One type is for the device, implementing ep0.
54 * The other type is for each IN or OUT endpoint. In both cases, the
55 * user mode driver must configure the hardware before using it.
57 * - First, dev_config() is called when /dev/gadget/$CHIP is configured
58 * (by writing configuration and device descriptors). Afterwards it
59 * may serve as a source of device events, used to handle all control
60 * requests other than basic enumeration.
62 * - Then, after a SET_CONFIGURATION control request, ep_config() is
63 * called when each /dev/gadget/ep* file is configured (by writing
64 * endpoint descriptors). Afterwards these files are used to write()
65 * IN data or to read() OUT data. To halt the endpoint, a "wrong
66 * direction" request is issued (like reading an IN endpoint).
68 * Unlike "usbfs" the only ioctl()s are for things that are rare, and maybe
69 * not possible on all hardware. For example, precise fault handling with
70 * respect to data left in endpoint fifos after aborted operations; or
71 * selective clearing of endpoint halts, to implement SET_INTERFACE.
74 #define DRIVER_DESC "USB Gadget filesystem"
75 #define DRIVER_VERSION "24 Aug 2004"
77 static const char driver_desc [] = DRIVER_DESC;
78 static const char shortname [] = "gadgetfs";
80 MODULE_DESCRIPTION (DRIVER_DESC);
81 MODULE_AUTHOR ("David Brownell");
82 MODULE_LICENSE ("GPL");
85 /*----------------------------------------------------------------------*/
87 #define GADGETFS_MAGIC 0xaee71ee7
88 #define DMA_ADDR_INVALID (~(dma_addr_t)0)
90 /* /dev/gadget/$CHIP represents ep0 and the whole device */
92 /* DISBLED is the initial state.
94 STATE_DEV_DISABLED = 0,
96 /* Only one open() of /dev/gadget/$CHIP; only one file tracks
97 * ep0/device i/o modes and binding to the controller. Driver
98 * must always write descriptors to initialize the device, then
99 * the device becomes UNCONNECTED until enumeration.
103 /* From then on, ep0 fd is in either of two basic modes:
104 * - (UN)CONNECTED: read usb_gadgetfs_event(s) from it
105 * - SETUP: read/write will transfer control data and succeed;
106 * or if "wrong direction", performs protocol stall
108 STATE_DEV_UNCONNECTED,
112 /* UNBOUND means the driver closed ep0, so the device won't be
113 * accessible again (DEV_DISABLED) until all fds are closed.
118 /* enough for the whole queue: most events invalidate others */
124 enum ep0_state state; /* P: lock */
125 struct usb_gadgetfs_event event [N_EVENT];
127 struct fasync_struct *fasync;
130 /* drivers reading ep0 MUST handle control requests (SETUP)
131 * reported that way; else the host will time out.
133 unsigned usermode_setup : 1,
139 unsigned setup_wLength;
141 /* the rest is basically write-once */
142 struct usb_config_descriptor *config, *hs_config;
143 struct usb_device_descriptor *dev;
144 struct usb_request *req;
145 struct usb_gadget *gadget;
146 struct list_head epfiles;
148 wait_queue_head_t wait;
149 struct super_block *sb;
150 struct dentry *dentry;
152 /* except this scratch i/o buffer for ep0 */
156 static inline void get_dev (struct dev_data *data)
158 atomic_inc (&data->count);
161 static void put_dev (struct dev_data *data)
163 if (likely (!atomic_dec_and_test (&data->count)))
165 /* needs no more cleanup */
166 BUG_ON (waitqueue_active (&data->wait));
170 static struct dev_data *dev_new (void)
172 struct dev_data *dev;
174 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
177 dev->state = STATE_DEV_DISABLED;
178 atomic_set (&dev->count, 1);
179 spin_lock_init (&dev->lock);
180 INIT_LIST_HEAD (&dev->epfiles);
181 init_waitqueue_head (&dev->wait);
185 /*----------------------------------------------------------------------*/
187 /* other /dev/gadget/$ENDPOINT files represent endpoints */
189 STATE_EP_DISABLED = 0,
199 struct dev_data *dev;
200 /* must hold dev->lock before accessing ep or req */
202 struct usb_request *req;
205 struct usb_endpoint_descriptor desc, hs_desc;
206 struct list_head epfiles;
207 wait_queue_head_t wait;
208 struct dentry *dentry;
212 static inline void get_ep (struct ep_data *data)
214 atomic_inc (&data->count);
217 static void put_ep (struct ep_data *data)
219 if (likely (!atomic_dec_and_test (&data->count)))
222 /* needs no more cleanup */
223 BUG_ON (!list_empty (&data->epfiles));
224 BUG_ON (waitqueue_active (&data->wait));
228 /*----------------------------------------------------------------------*/
230 /* most "how to use the hardware" policy choices are in userspace:
231 * mapping endpoint roles (which the driver needs) to the capabilities
232 * which the usb controller has. most of those capabilities are exposed
233 * implicitly, starting with the driver name and then endpoint names.
236 static const char *CHIP;
238 /*----------------------------------------------------------------------*/
240 /* NOTE: don't use dev_printk calls before binding to the gadget
241 * at the end of ep0 configuration, or after unbind.
244 /* too wordy: dev_printk(level , &(d)->gadget->dev , fmt , ## args) */
245 #define xprintk(d,level,fmt,args...) \
246 printk(level "%s: " fmt , shortname , ## args)
249 #define DBG(dev,fmt,args...) \
250 xprintk(dev , KERN_DEBUG , fmt , ## args)
252 #define DBG(dev,fmt,args...) \
259 #define VDEBUG(dev,fmt,args...) \
263 #define ERROR(dev,fmt,args...) \
264 xprintk(dev , KERN_ERR , fmt , ## args)
265 #define INFO(dev,fmt,args...) \
266 xprintk(dev , KERN_INFO , fmt , ## args)
269 /*----------------------------------------------------------------------*/
271 /* SYNCHRONOUS ENDPOINT OPERATIONS (bulk/intr/iso)
273 * After opening, configure non-control endpoints. Then use normal
274 * stream read() and write() requests; and maybe ioctl() to get more
275 * precise FIFO status when recovering from cancellation.
278 static void epio_complete (struct usb_ep *ep, struct usb_request *req)
280 struct ep_data *epdata = ep->driver_data;
285 epdata->status = req->status;
287 epdata->status = req->actual;
288 complete ((struct completion *)req->context);
291 /* tasklock endpoint, returning when it's connected.
292 * still need dev->lock to use epdata->ep.
295 get_ready_ep (unsigned f_flags, struct ep_data *epdata)
299 if (f_flags & O_NONBLOCK) {
300 if (!mutex_trylock(&epdata->lock))
302 if (epdata->state != STATE_EP_ENABLED) {
303 mutex_unlock(&epdata->lock);
311 val = mutex_lock_interruptible(&epdata->lock);
315 switch (epdata->state) {
316 case STATE_EP_ENABLED:
318 // case STATE_EP_DISABLED: /* "can't happen" */
319 // case STATE_EP_READY: /* "can't happen" */
320 default: /* error! */
321 pr_debug ("%s: ep %p not available, state %d\n",
322 shortname, epdata, epdata->state);
324 case STATE_EP_UNBOUND: /* clean disconnect */
326 mutex_unlock(&epdata->lock);
332 ep_io (struct ep_data *epdata, void *buf, unsigned len)
334 DECLARE_COMPLETION_ONSTACK (done);
337 spin_lock_irq (&epdata->dev->lock);
338 if (likely (epdata->ep != NULL)) {
339 struct usb_request *req = epdata->req;
341 req->context = &done;
342 req->complete = epio_complete;
345 value = usb_ep_queue (epdata->ep, req, GFP_ATOMIC);
348 spin_unlock_irq (&epdata->dev->lock);
350 if (likely (value == 0)) {
351 value = wait_event_interruptible (done.wait, done.done);
353 spin_lock_irq (&epdata->dev->lock);
354 if (likely (epdata->ep != NULL)) {
355 DBG (epdata->dev, "%s i/o interrupted\n",
357 usb_ep_dequeue (epdata->ep, epdata->req);
358 spin_unlock_irq (&epdata->dev->lock);
360 wait_event (done.wait, done.done);
361 if (epdata->status == -ECONNRESET)
362 epdata->status = -EINTR;
364 spin_unlock_irq (&epdata->dev->lock);
366 DBG (epdata->dev, "endpoint gone\n");
367 epdata->status = -ENODEV;
370 return epdata->status;
376 /* handle a synchronous OUT bulk/intr/iso transfer */
378 ep_read (struct file *fd, char __user *buf, size_t len, loff_t *ptr)
380 struct ep_data *data = fd->private_data;
384 if ((value = get_ready_ep (fd->f_flags, data)) < 0)
387 /* halt any endpoint by doing a "wrong direction" i/o call */
388 if (usb_endpoint_dir_in(&data->desc)) {
389 if (usb_endpoint_xfer_isoc(&data->desc))
391 DBG (data->dev, "%s halt\n", data->name);
392 spin_lock_irq (&data->dev->lock);
393 if (likely (data->ep != NULL))
394 usb_ep_set_halt (data->ep);
395 spin_unlock_irq (&data->dev->lock);
396 mutex_unlock(&data->lock);
400 /* FIXME readahead for O_NONBLOCK and poll(); careful with ZLPs */
403 kbuf = kmalloc (len, GFP_KERNEL);
404 if (unlikely (!kbuf))
407 value = ep_io (data, kbuf, len);
408 VDEBUG (data->dev, "%s read %zu OUT, status %d\n",
409 data->name, len, (int) value);
410 if (value >= 0 && copy_to_user (buf, kbuf, value))
414 mutex_unlock(&data->lock);
419 /* handle a synchronous IN bulk/intr/iso transfer */
421 ep_write (struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
423 struct ep_data *data = fd->private_data;
427 if ((value = get_ready_ep (fd->f_flags, data)) < 0)
430 /* halt any endpoint by doing a "wrong direction" i/o call */
431 if (!usb_endpoint_dir_in(&data->desc)) {
432 if (usb_endpoint_xfer_isoc(&data->desc))
434 DBG (data->dev, "%s halt\n", data->name);
435 spin_lock_irq (&data->dev->lock);
436 if (likely (data->ep != NULL))
437 usb_ep_set_halt (data->ep);
438 spin_unlock_irq (&data->dev->lock);
439 mutex_unlock(&data->lock);
443 /* FIXME writebehind for O_NONBLOCK and poll(), qlen = 1 */
446 kbuf = kmalloc (len, GFP_KERNEL);
449 if (copy_from_user (kbuf, buf, len)) {
454 value = ep_io (data, kbuf, len);
455 VDEBUG (data->dev, "%s write %zu IN, status %d\n",
456 data->name, len, (int) value);
458 mutex_unlock(&data->lock);
464 ep_release (struct inode *inode, struct file *fd)
466 struct ep_data *data = fd->private_data;
469 value = mutex_lock_interruptible(&data->lock);
473 /* clean up if this can be reopened */
474 if (data->state != STATE_EP_UNBOUND) {
475 data->state = STATE_EP_DISABLED;
476 data->desc.bDescriptorType = 0;
477 data->hs_desc.bDescriptorType = 0;
478 usb_ep_disable(data->ep);
480 mutex_unlock(&data->lock);
485 static long ep_ioctl(struct file *fd, unsigned code, unsigned long value)
487 struct ep_data *data = fd->private_data;
490 if ((status = get_ready_ep (fd->f_flags, data)) < 0)
493 spin_lock_irq (&data->dev->lock);
494 if (likely (data->ep != NULL)) {
496 case GADGETFS_FIFO_STATUS:
497 status = usb_ep_fifo_status (data->ep);
499 case GADGETFS_FIFO_FLUSH:
500 usb_ep_fifo_flush (data->ep);
502 case GADGETFS_CLEAR_HALT:
503 status = usb_ep_clear_halt (data->ep);
510 spin_unlock_irq (&data->dev->lock);
511 mutex_unlock(&data->lock);
515 /*----------------------------------------------------------------------*/
517 /* ASYNCHRONOUS ENDPOINT I/O OPERATIONS (bulk/intr/iso) */
520 struct usb_request *req;
521 struct ep_data *epdata;
523 const struct iovec *iv;
524 unsigned long nr_segs;
528 static int ep_aio_cancel(struct kiocb *iocb, struct io_event *e)
530 struct kiocb_priv *priv = iocb->private;
531 struct ep_data *epdata;
535 epdata = priv->epdata;
536 // spin_lock(&epdata->dev->lock);
537 kiocbSetCancelled(iocb);
538 if (likely(epdata && epdata->ep && priv->req))
539 value = usb_ep_dequeue (epdata->ep, priv->req);
542 // spin_unlock(&epdata->dev->lock);
549 static ssize_t ep_aio_read_retry(struct kiocb *iocb)
551 struct kiocb_priv *priv = iocb->private;
556 /* we "retry" to get the right mm context for this: */
558 /* copy stuff into user buffers */
559 total = priv->actual;
562 for (i=0; i < priv->nr_segs; i++) {
563 ssize_t this = min((ssize_t)(priv->iv[i].iov_len), total);
565 if (copy_to_user(priv->iv[i].iov_base, to_copy, this)) {
582 static void ep_aio_complete(struct usb_ep *ep, struct usb_request *req)
584 struct kiocb *iocb = req->context;
585 struct kiocb_priv *priv = iocb->private;
586 struct ep_data *epdata = priv->epdata;
588 /* lock against disconnect (and ideally, cancel) */
589 spin_lock(&epdata->dev->lock);
593 /* if this was a write or a read returning no data then we
594 * don't need to copy anything to userspace, so we can
595 * complete the aio request immediately.
597 if (priv->iv == NULL || unlikely(req->actual == 0)) {
600 iocb->private = NULL;
601 /* aio_complete() reports bytes-transferred _and_ faults */
602 aio_complete(iocb, req->actual ? req->actual : req->status,
605 /* retry() won't report both; so we hide some faults */
606 if (unlikely(0 != req->status))
607 DBG(epdata->dev, "%s fault %d len %d\n",
608 ep->name, req->status, req->actual);
610 priv->buf = req->buf;
611 priv->actual = req->actual;
614 spin_unlock(&epdata->dev->lock);
616 usb_ep_free_request(ep, req);
625 struct ep_data *epdata,
626 const struct iovec *iv,
627 unsigned long nr_segs
630 struct kiocb_priv *priv;
631 struct usb_request *req;
634 priv = kmalloc(sizeof *priv, GFP_KERNEL);
641 iocb->private = priv;
643 priv->nr_segs = nr_segs;
645 value = get_ready_ep(iocb->ki_filp->f_flags, epdata);
646 if (unlikely(value < 0)) {
651 iocb->ki_cancel = ep_aio_cancel;
653 priv->epdata = epdata;
656 /* each kiocb is coupled to one usb_request, but we can't
657 * allocate or submit those if the host disconnected.
659 spin_lock_irq(&epdata->dev->lock);
660 if (likely(epdata->ep)) {
661 req = usb_ep_alloc_request(epdata->ep, GFP_ATOMIC);
666 req->complete = ep_aio_complete;
668 value = usb_ep_queue(epdata->ep, req, GFP_ATOMIC);
669 if (unlikely(0 != value))
670 usb_ep_free_request(epdata->ep, req);
675 spin_unlock_irq(&epdata->dev->lock);
677 mutex_unlock(&epdata->lock);
679 if (unlikely(value)) {
683 value = (iv ? -EIOCBRETRY : -EIOCBQUEUED);
688 ep_aio_read(struct kiocb *iocb, const struct iovec *iov,
689 unsigned long nr_segs, loff_t o)
691 struct ep_data *epdata = iocb->ki_filp->private_data;
694 if (unlikely(usb_endpoint_dir_in(&epdata->desc)))
697 buf = kmalloc(iocb->ki_left, GFP_KERNEL);
701 iocb->ki_retry = ep_aio_read_retry;
702 return ep_aio_rwtail(iocb, buf, iocb->ki_left, epdata, iov, nr_segs);
706 ep_aio_write(struct kiocb *iocb, const struct iovec *iov,
707 unsigned long nr_segs, loff_t o)
709 struct ep_data *epdata = iocb->ki_filp->private_data;
714 if (unlikely(!usb_endpoint_dir_in(&epdata->desc)))
717 buf = kmalloc(iocb->ki_left, GFP_KERNEL);
721 for (i=0; i < nr_segs; i++) {
722 if (unlikely(copy_from_user(&buf[len], iov[i].iov_base,
723 iov[i].iov_len) != 0)) {
727 len += iov[i].iov_len;
729 return ep_aio_rwtail(iocb, buf, len, epdata, NULL, 0);
732 /*----------------------------------------------------------------------*/
734 /* used after endpoint configuration */
735 static const struct file_operations ep_io_operations = {
736 .owner = THIS_MODULE,
741 .unlocked_ioctl = ep_ioctl,
742 .release = ep_release,
744 .aio_read = ep_aio_read,
745 .aio_write = ep_aio_write,
748 /* ENDPOINT INITIALIZATION
750 * fd = open ("/dev/gadget/$ENDPOINT", O_RDWR)
751 * status = write (fd, descriptors, sizeof descriptors)
753 * That write establishes the endpoint configuration, configuring
754 * the controller to process bulk, interrupt, or isochronous transfers
755 * at the right maxpacket size, and so on.
757 * The descriptors are message type 1, identified by a host order u32
758 * at the beginning of what's written. Descriptor order is: full/low
759 * speed descriptor, then optional high speed descriptor.
762 ep_config (struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
764 struct ep_data *data = fd->private_data;
767 int value, length = len;
769 value = mutex_lock_interruptible(&data->lock);
773 if (data->state != STATE_EP_READY) {
779 if (len < USB_DT_ENDPOINT_SIZE + 4)
782 /* we might need to change message format someday */
783 if (copy_from_user (&tag, buf, 4)) {
787 DBG(data->dev, "config %s, bad tag %d\n", data->name, tag);
793 /* NOTE: audio endpoint extensions not accepted here;
794 * just don't include the extra bytes.
797 /* full/low speed descriptor, then high speed */
798 if (copy_from_user (&data->desc, buf, USB_DT_ENDPOINT_SIZE)) {
801 if (data->desc.bLength != USB_DT_ENDPOINT_SIZE
802 || data->desc.bDescriptorType != USB_DT_ENDPOINT)
804 if (len != USB_DT_ENDPOINT_SIZE) {
805 if (len != 2 * USB_DT_ENDPOINT_SIZE)
807 if (copy_from_user (&data->hs_desc, buf + USB_DT_ENDPOINT_SIZE,
808 USB_DT_ENDPOINT_SIZE)) {
811 if (data->hs_desc.bLength != USB_DT_ENDPOINT_SIZE
812 || data->hs_desc.bDescriptorType
813 != USB_DT_ENDPOINT) {
814 DBG(data->dev, "config %s, bad hs length or type\n",
820 spin_lock_irq (&data->dev->lock);
821 if (data->dev->state == STATE_DEV_UNBOUND) {
824 } else if ((ep = data->ep) == NULL) {
828 switch (data->dev->gadget->speed) {
831 value = usb_ep_enable (ep, &data->desc);
833 data->state = STATE_EP_ENABLED;
835 #ifdef CONFIG_USB_GADGET_DUALSPEED
837 /* fails if caller didn't provide that descriptor... */
838 value = usb_ep_enable (ep, &data->hs_desc);
840 data->state = STATE_EP_ENABLED;
844 DBG(data->dev, "unconnected, %s init abandoned\n",
849 fd->f_op = &ep_io_operations;
853 spin_unlock_irq (&data->dev->lock);
856 data->desc.bDescriptorType = 0;
857 data->hs_desc.bDescriptorType = 0;
859 mutex_unlock(&data->lock);
870 ep_open (struct inode *inode, struct file *fd)
872 struct ep_data *data = inode->i_private;
875 if (mutex_lock_interruptible(&data->lock) != 0)
877 spin_lock_irq (&data->dev->lock);
878 if (data->dev->state == STATE_DEV_UNBOUND)
880 else if (data->state == STATE_EP_DISABLED) {
882 data->state = STATE_EP_READY;
884 fd->private_data = data;
885 VDEBUG (data->dev, "%s ready\n", data->name);
887 DBG (data->dev, "%s state %d\n",
888 data->name, data->state);
889 spin_unlock_irq (&data->dev->lock);
890 mutex_unlock(&data->lock);
894 /* used before endpoint configuration */
895 static const struct file_operations ep_config_operations = {
896 .owner = THIS_MODULE,
901 .release = ep_release,
904 /*----------------------------------------------------------------------*/
906 /* EP0 IMPLEMENTATION can be partly in userspace.
908 * Drivers that use this facility receive various events, including
909 * control requests the kernel doesn't handle. Drivers that don't
910 * use this facility may be too simple-minded for real applications.
913 static inline void ep0_readable (struct dev_data *dev)
915 wake_up (&dev->wait);
916 kill_fasync (&dev->fasync, SIGIO, POLL_IN);
919 static void clean_req (struct usb_ep *ep, struct usb_request *req)
921 struct dev_data *dev = ep->driver_data;
923 if (req->buf != dev->rbuf) {
925 req->buf = dev->rbuf;
926 req->dma = DMA_ADDR_INVALID;
928 req->complete = epio_complete;
929 dev->setup_out_ready = 0;
932 static void ep0_complete (struct usb_ep *ep, struct usb_request *req)
934 struct dev_data *dev = ep->driver_data;
938 /* for control OUT, data must still get to userspace */
939 spin_lock_irqsave(&dev->lock, flags);
940 if (!dev->setup_in) {
941 dev->setup_out_error = (req->status != 0);
942 if (!dev->setup_out_error)
944 dev->setup_out_ready = 1;
948 /* clean up as appropriate */
949 if (free && req->buf != &dev->rbuf)
951 req->complete = epio_complete;
952 spin_unlock_irqrestore(&dev->lock, flags);
955 static int setup_req (struct usb_ep *ep, struct usb_request *req, u16 len)
957 struct dev_data *dev = ep->driver_data;
959 if (dev->setup_out_ready) {
960 DBG (dev, "ep0 request busy!\n");
963 if (len > sizeof (dev->rbuf))
964 req->buf = kmalloc(len, GFP_ATOMIC);
965 if (req->buf == NULL) {
966 req->buf = dev->rbuf;
969 req->complete = ep0_complete;
976 ep0_read (struct file *fd, char __user *buf, size_t len, loff_t *ptr)
978 struct dev_data *dev = fd->private_data;
980 enum ep0_state state;
982 spin_lock_irq (&dev->lock);
984 /* report fd mode change before acting on it */
985 if (dev->setup_abort) {
986 dev->setup_abort = 0;
991 /* control DATA stage */
992 if ((state = dev->state) == STATE_DEV_SETUP) {
994 if (dev->setup_in) { /* stall IN */
995 VDEBUG(dev, "ep0in stall\n");
996 (void) usb_ep_set_halt (dev->gadget->ep0);
998 dev->state = STATE_DEV_CONNECTED;
1000 } else if (len == 0) { /* ack SET_CONFIGURATION etc */
1001 struct usb_ep *ep = dev->gadget->ep0;
1002 struct usb_request *req = dev->req;
1004 if ((retval = setup_req (ep, req, 0)) == 0)
1005 retval = usb_ep_queue (ep, req, GFP_ATOMIC);
1006 dev->state = STATE_DEV_CONNECTED;
1008 /* assume that was SET_CONFIGURATION */
1009 if (dev->current_config) {
1012 if (gadget_is_dualspeed(dev->gadget)
1013 && (dev->gadget->speed
1015 power = dev->hs_config->bMaxPower;
1017 power = dev->config->bMaxPower;
1018 usb_gadget_vbus_draw(dev->gadget, 2 * power);
1021 } else { /* collect OUT data */
1022 if ((fd->f_flags & O_NONBLOCK) != 0
1023 && !dev->setup_out_ready) {
1027 spin_unlock_irq (&dev->lock);
1028 retval = wait_event_interruptible (dev->wait,
1029 dev->setup_out_ready != 0);
1031 /* FIXME state could change from under us */
1032 spin_lock_irq (&dev->lock);
1036 if (dev->state != STATE_DEV_SETUP) {
1037 retval = -ECANCELED;
1040 dev->state = STATE_DEV_CONNECTED;
1042 if (dev->setup_out_error)
1045 len = min (len, (size_t)dev->req->actual);
1046 // FIXME don't call this with the spinlock held ...
1047 if (copy_to_user (buf, dev->req->buf, len))
1049 clean_req (dev->gadget->ep0, dev->req);
1050 /* NOTE userspace can't yet choose to stall */
1056 /* else normal: return event data */
1057 if (len < sizeof dev->event [0]) {
1061 len -= len % sizeof (struct usb_gadgetfs_event);
1062 dev->usermode_setup = 1;
1065 /* return queued events right away */
1066 if (dev->ev_next != 0) {
1069 n = len / sizeof (struct usb_gadgetfs_event);
1070 if (dev->ev_next < n)
1073 /* ep0 i/o has special semantics during STATE_DEV_SETUP */
1074 for (i = 0; i < n; i++) {
1075 if (dev->event [i].type == GADGETFS_SETUP) {
1076 dev->state = STATE_DEV_SETUP;
1081 spin_unlock_irq (&dev->lock);
1082 len = n * sizeof (struct usb_gadgetfs_event);
1083 if (copy_to_user (buf, &dev->event, len))
1088 /* NOTE this doesn't guard against broken drivers;
1089 * concurrent ep0 readers may lose events.
1091 spin_lock_irq (&dev->lock);
1092 if (dev->ev_next > n) {
1093 memmove(&dev->event[0], &dev->event[n],
1094 sizeof (struct usb_gadgetfs_event)
1095 * (dev->ev_next - n));
1098 spin_unlock_irq (&dev->lock);
1102 if (fd->f_flags & O_NONBLOCK) {
1109 DBG (dev, "fail %s, state %d\n", __func__, state);
1112 case STATE_DEV_UNCONNECTED:
1113 case STATE_DEV_CONNECTED:
1114 spin_unlock_irq (&dev->lock);
1115 DBG (dev, "%s wait\n", __func__);
1117 /* wait for events */
1118 retval = wait_event_interruptible (dev->wait,
1122 spin_lock_irq (&dev->lock);
1127 spin_unlock_irq (&dev->lock);
1131 static struct usb_gadgetfs_event *
1132 next_event (struct dev_data *dev, enum usb_gadgetfs_event_type type)
1134 struct usb_gadgetfs_event *event;
1138 /* these events purge the queue */
1139 case GADGETFS_DISCONNECT:
1140 if (dev->state == STATE_DEV_SETUP)
1141 dev->setup_abort = 1;
1143 case GADGETFS_CONNECT:
1146 case GADGETFS_SETUP: /* previous request timed out */
1147 case GADGETFS_SUSPEND: /* same effect */
1148 /* these events can't be repeated */
1149 for (i = 0; i != dev->ev_next; i++) {
1150 if (dev->event [i].type != type)
1152 DBG(dev, "discard old event[%d] %d\n", i, type);
1154 if (i == dev->ev_next)
1156 /* indices start at zero, for simplicity */
1157 memmove (&dev->event [i], &dev->event [i + 1],
1158 sizeof (struct usb_gadgetfs_event)
1159 * (dev->ev_next - i));
1165 VDEBUG(dev, "event[%d] = %d\n", dev->ev_next, type);
1166 event = &dev->event [dev->ev_next++];
1167 BUG_ON (dev->ev_next > N_EVENT);
1168 memset (event, 0, sizeof *event);
1174 ep0_write (struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
1176 struct dev_data *dev = fd->private_data;
1177 ssize_t retval = -ESRCH;
1179 spin_lock_irq (&dev->lock);
1181 /* report fd mode change before acting on it */
1182 if (dev->setup_abort) {
1183 dev->setup_abort = 0;
1186 /* data and/or status stage for control request */
1187 } else if (dev->state == STATE_DEV_SETUP) {
1189 /* IN DATA+STATUS caller makes len <= wLength */
1190 if (dev->setup_in) {
1191 retval = setup_req (dev->gadget->ep0, dev->req, len);
1193 dev->state = STATE_DEV_CONNECTED;
1194 spin_unlock_irq (&dev->lock);
1195 if (copy_from_user (dev->req->buf, buf, len))
1198 if (len < dev->setup_wLength)
1200 retval = usb_ep_queue (
1201 dev->gadget->ep0, dev->req,
1205 spin_lock_irq (&dev->lock);
1206 clean_req (dev->gadget->ep0, dev->req);
1207 spin_unlock_irq (&dev->lock);
1214 /* can stall some OUT transfers */
1215 } else if (dev->setup_can_stall) {
1216 VDEBUG(dev, "ep0out stall\n");
1217 (void) usb_ep_set_halt (dev->gadget->ep0);
1219 dev->state = STATE_DEV_CONNECTED;
1221 DBG(dev, "bogus ep0out stall!\n");
1224 DBG (dev, "fail %s, state %d\n", __func__, dev->state);
1226 spin_unlock_irq (&dev->lock);
1231 ep0_fasync (int f, struct file *fd, int on)
1233 struct dev_data *dev = fd->private_data;
1234 // caller must F_SETOWN before signal delivery happens
1235 VDEBUG (dev, "%s %s\n", __func__, on ? "on" : "off");
1236 return fasync_helper (f, fd, on, &dev->fasync);
1239 static struct usb_gadget_driver gadgetfs_driver;
1242 dev_release (struct inode *inode, struct file *fd)
1244 struct dev_data *dev = fd->private_data;
1246 /* closing ep0 === shutdown all */
1248 usb_gadget_unregister_driver (&gadgetfs_driver);
1250 /* at this point "good" hardware has disconnected the
1251 * device from USB; the host won't see it any more.
1252 * alternatively, all host requests will time out.
1259 /* other endpoints were all decoupled from this device */
1260 spin_lock_irq(&dev->lock);
1261 dev->state = STATE_DEV_DISABLED;
1262 spin_unlock_irq(&dev->lock);
1267 ep0_poll (struct file *fd, poll_table *wait)
1269 struct dev_data *dev = fd->private_data;
1272 poll_wait(fd, &dev->wait, wait);
1274 spin_lock_irq (&dev->lock);
1276 /* report fd mode change before acting on it */
1277 if (dev->setup_abort) {
1278 dev->setup_abort = 0;
1283 if (dev->state == STATE_DEV_SETUP) {
1284 if (dev->setup_in || dev->setup_can_stall)
1287 if (dev->ev_next != 0)
1291 spin_unlock_irq(&dev->lock);
1295 static long dev_ioctl (struct file *fd, unsigned code, unsigned long value)
1297 struct dev_data *dev = fd->private_data;
1298 struct usb_gadget *gadget = dev->gadget;
1301 if (gadget->ops->ioctl)
1302 ret = gadget->ops->ioctl (gadget, code, value);
1307 /* used after device configuration */
1308 static const struct file_operations ep0_io_operations = {
1309 .owner = THIS_MODULE,
1310 .llseek = no_llseek,
1314 .fasync = ep0_fasync,
1316 .unlocked_ioctl = dev_ioctl,
1317 .release = dev_release,
1320 /*----------------------------------------------------------------------*/
1322 /* The in-kernel gadget driver handles most ep0 issues, in particular
1323 * enumerating the single configuration (as provided from user space).
1325 * Unrecognized ep0 requests may be handled in user space.
1328 #ifdef CONFIG_USB_GADGET_DUALSPEED
1329 static void make_qualifier (struct dev_data *dev)
1331 struct usb_qualifier_descriptor qual;
1332 struct usb_device_descriptor *desc;
1334 qual.bLength = sizeof qual;
1335 qual.bDescriptorType = USB_DT_DEVICE_QUALIFIER;
1336 qual.bcdUSB = cpu_to_le16 (0x0200);
1339 qual.bDeviceClass = desc->bDeviceClass;
1340 qual.bDeviceSubClass = desc->bDeviceSubClass;
1341 qual.bDeviceProtocol = desc->bDeviceProtocol;
1343 /* assumes ep0 uses the same value for both speeds ... */
1344 qual.bMaxPacketSize0 = desc->bMaxPacketSize0;
1346 qual.bNumConfigurations = 1;
1349 memcpy (dev->rbuf, &qual, sizeof qual);
1354 config_buf (struct dev_data *dev, u8 type, unsigned index)
1359 /* only one configuration */
1363 if (gadget_is_dualspeed(dev->gadget)) {
1364 hs = (dev->gadget->speed == USB_SPEED_HIGH);
1365 if (type == USB_DT_OTHER_SPEED_CONFIG)
1369 dev->req->buf = dev->hs_config;
1370 len = le16_to_cpu(dev->hs_config->wTotalLength);
1372 dev->req->buf = dev->config;
1373 len = le16_to_cpu(dev->config->wTotalLength);
1375 ((u8 *)dev->req->buf) [1] = type;
1380 gadgetfs_setup (struct usb_gadget *gadget, const struct usb_ctrlrequest *ctrl)
1382 struct dev_data *dev = get_gadget_data (gadget);
1383 struct usb_request *req = dev->req;
1384 int value = -EOPNOTSUPP;
1385 struct usb_gadgetfs_event *event;
1386 u16 w_value = le16_to_cpu(ctrl->wValue);
1387 u16 w_length = le16_to_cpu(ctrl->wLength);
1389 spin_lock (&dev->lock);
1390 dev->setup_abort = 0;
1391 if (dev->state == STATE_DEV_UNCONNECTED) {
1392 if (gadget_is_dualspeed(gadget)
1393 && gadget->speed == USB_SPEED_HIGH
1394 && dev->hs_config == NULL) {
1395 spin_unlock(&dev->lock);
1396 ERROR (dev, "no high speed config??\n");
1400 dev->state = STATE_DEV_CONNECTED;
1401 dev->dev->bMaxPacketSize0 = gadget->ep0->maxpacket;
1403 INFO (dev, "connected\n");
1404 event = next_event (dev, GADGETFS_CONNECT);
1405 event->u.speed = gadget->speed;
1408 /* host may have given up waiting for response. we can miss control
1409 * requests handled lower down (device/endpoint status and features);
1410 * then ep0_{read,write} will report the wrong status. controller
1411 * driver will have aborted pending i/o.
1413 } else if (dev->state == STATE_DEV_SETUP)
1414 dev->setup_abort = 1;
1416 req->buf = dev->rbuf;
1417 req->dma = DMA_ADDR_INVALID;
1418 req->context = NULL;
1419 value = -EOPNOTSUPP;
1420 switch (ctrl->bRequest) {
1422 case USB_REQ_GET_DESCRIPTOR:
1423 if (ctrl->bRequestType != USB_DIR_IN)
1425 switch (w_value >> 8) {
1428 value = min (w_length, (u16) sizeof *dev->dev);
1429 req->buf = dev->dev;
1431 #ifdef CONFIG_USB_GADGET_DUALSPEED
1432 case USB_DT_DEVICE_QUALIFIER:
1433 if (!dev->hs_config)
1435 value = min (w_length, (u16)
1436 sizeof (struct usb_qualifier_descriptor));
1437 make_qualifier (dev);
1439 case USB_DT_OTHER_SPEED_CONFIG:
1443 value = config_buf (dev,
1447 value = min (w_length, (u16) value);
1452 default: // all others are errors
1457 /* currently one config, two speeds */
1458 case USB_REQ_SET_CONFIGURATION:
1459 if (ctrl->bRequestType != 0)
1461 if (0 == (u8) w_value) {
1463 dev->current_config = 0;
1464 usb_gadget_vbus_draw(gadget, 8 /* mA */ );
1465 // user mode expected to disable endpoints
1469 if (gadget_is_dualspeed(gadget)
1470 && gadget->speed == USB_SPEED_HIGH) {
1471 config = dev->hs_config->bConfigurationValue;
1472 power = dev->hs_config->bMaxPower;
1474 config = dev->config->bConfigurationValue;
1475 power = dev->config->bMaxPower;
1478 if (config == (u8) w_value) {
1480 dev->current_config = config;
1481 usb_gadget_vbus_draw(gadget, 2 * power);
1485 /* report SET_CONFIGURATION like any other control request,
1486 * except that usermode may not stall this. the next
1487 * request mustn't be allowed start until this finishes:
1488 * endpoints and threads set up, etc.
1490 * NOTE: older PXA hardware (before PXA 255: without UDCCFR)
1491 * has bad/racey automagic that prevents synchronizing here.
1492 * even kernel mode drivers often miss them.
1495 INFO (dev, "configuration #%d\n", dev->current_config);
1496 if (dev->usermode_setup) {
1497 dev->setup_can_stall = 0;
1503 #ifndef CONFIG_USB_GADGET_PXA25X
1504 /* PXA automagically handles this request too */
1505 case USB_REQ_GET_CONFIGURATION:
1506 if (ctrl->bRequestType != 0x80)
1508 *(u8 *)req->buf = dev->current_config;
1509 value = min (w_length, (u16) 1);
1515 VDEBUG (dev, "%s req%02x.%02x v%04x i%04x l%d\n",
1516 dev->usermode_setup ? "delegate" : "fail",
1517 ctrl->bRequestType, ctrl->bRequest,
1518 w_value, le16_to_cpu(ctrl->wIndex), w_length);
1520 /* if there's an ep0 reader, don't stall */
1521 if (dev->usermode_setup) {
1522 dev->setup_can_stall = 1;
1524 dev->setup_in = (ctrl->bRequestType & USB_DIR_IN)
1526 dev->setup_wLength = w_length;
1527 dev->setup_out_ready = 0;
1528 dev->setup_out_error = 0;
1531 /* read DATA stage for OUT right away */
1532 if (unlikely (!dev->setup_in && w_length)) {
1533 value = setup_req (gadget->ep0, dev->req,
1537 value = usb_ep_queue (gadget->ep0, dev->req,
1540 clean_req (gadget->ep0, dev->req);
1544 /* we can't currently stall these */
1545 dev->setup_can_stall = 0;
1548 /* state changes when reader collects event */
1549 event = next_event (dev, GADGETFS_SETUP);
1550 event->u.setup = *ctrl;
1552 spin_unlock (&dev->lock);
1557 /* proceed with data transfer and status phases? */
1558 if (value >= 0 && dev->state != STATE_DEV_SETUP) {
1559 req->length = value;
1560 req->zero = value < w_length;
1561 value = usb_ep_queue (gadget->ep0, req, GFP_ATOMIC);
1563 DBG (dev, "ep_queue --> %d\n", value);
1568 /* device stalls when value < 0 */
1569 spin_unlock (&dev->lock);
1573 static void destroy_ep_files (struct dev_data *dev)
1575 struct list_head *entry, *tmp;
1577 DBG (dev, "%s %d\n", __func__, dev->state);
1579 /* dev->state must prevent interference */
1581 spin_lock_irq (&dev->lock);
1582 list_for_each_safe (entry, tmp, &dev->epfiles) {
1584 struct inode *parent;
1585 struct dentry *dentry;
1587 /* break link to FS */
1588 ep = list_entry (entry, struct ep_data, epfiles);
1589 list_del_init (&ep->epfiles);
1590 dentry = ep->dentry;
1592 parent = dentry->d_parent->d_inode;
1594 /* break link to controller */
1595 if (ep->state == STATE_EP_ENABLED)
1596 (void) usb_ep_disable (ep->ep);
1597 ep->state = STATE_EP_UNBOUND;
1598 usb_ep_free_request (ep->ep, ep->req);
1600 wake_up (&ep->wait);
1603 spin_unlock_irq (&dev->lock);
1605 /* break link to dcache */
1606 mutex_lock (&parent->i_mutex);
1609 mutex_unlock (&parent->i_mutex);
1611 /* fds may still be open */
1614 spin_unlock_irq (&dev->lock);
1618 static struct inode *
1619 gadgetfs_create_file (struct super_block *sb, char const *name,
1620 void *data, const struct file_operations *fops,
1621 struct dentry **dentry_p);
1623 static int activate_ep_files (struct dev_data *dev)
1626 struct ep_data *data;
1628 gadget_for_each_ep (ep, dev->gadget) {
1630 data = kzalloc(sizeof(*data), GFP_KERNEL);
1633 data->state = STATE_EP_DISABLED;
1634 mutex_init(&data->lock);
1635 init_waitqueue_head (&data->wait);
1637 strncpy (data->name, ep->name, sizeof (data->name) - 1);
1638 atomic_set (&data->count, 1);
1643 ep->driver_data = data;
1645 data->req = usb_ep_alloc_request (ep, GFP_KERNEL);
1649 data->inode = gadgetfs_create_file (dev->sb, data->name,
1650 data, &ep_config_operations,
1654 list_add_tail (&data->epfiles, &dev->epfiles);
1659 usb_ep_free_request (ep, data->req);
1664 DBG (dev, "%s enomem\n", __func__);
1665 destroy_ep_files (dev);
1670 gadgetfs_unbind (struct usb_gadget *gadget)
1672 struct dev_data *dev = get_gadget_data (gadget);
1674 DBG (dev, "%s\n", __func__);
1676 spin_lock_irq (&dev->lock);
1677 dev->state = STATE_DEV_UNBOUND;
1678 spin_unlock_irq (&dev->lock);
1680 destroy_ep_files (dev);
1681 gadget->ep0->driver_data = NULL;
1682 set_gadget_data (gadget, NULL);
1684 /* we've already been disconnected ... no i/o is active */
1686 usb_ep_free_request (gadget->ep0, dev->req);
1687 DBG (dev, "%s done\n", __func__);
1691 static struct dev_data *the_device;
1694 gadgetfs_bind (struct usb_gadget *gadget)
1696 struct dev_data *dev = the_device;
1700 if (0 != strcmp (CHIP, gadget->name)) {
1701 pr_err("%s expected %s controller not %s\n",
1702 shortname, CHIP, gadget->name);
1706 set_gadget_data (gadget, dev);
1707 dev->gadget = gadget;
1708 gadget->ep0->driver_data = dev;
1709 dev->dev->bMaxPacketSize0 = gadget->ep0->maxpacket;
1711 /* preallocate control response and buffer */
1712 dev->req = usb_ep_alloc_request (gadget->ep0, GFP_KERNEL);
1715 dev->req->context = NULL;
1716 dev->req->complete = epio_complete;
1718 if (activate_ep_files (dev) < 0)
1721 INFO (dev, "bound to %s driver\n", gadget->name);
1722 spin_lock_irq(&dev->lock);
1723 dev->state = STATE_DEV_UNCONNECTED;
1724 spin_unlock_irq(&dev->lock);
1729 gadgetfs_unbind (gadget);
1734 gadgetfs_disconnect (struct usb_gadget *gadget)
1736 struct dev_data *dev = get_gadget_data (gadget);
1738 spin_lock (&dev->lock);
1739 if (dev->state == STATE_DEV_UNCONNECTED)
1741 dev->state = STATE_DEV_UNCONNECTED;
1743 INFO (dev, "disconnected\n");
1744 next_event (dev, GADGETFS_DISCONNECT);
1747 spin_unlock (&dev->lock);
1751 gadgetfs_suspend (struct usb_gadget *gadget)
1753 struct dev_data *dev = get_gadget_data (gadget);
1755 INFO (dev, "suspended from state %d\n", dev->state);
1756 spin_lock (&dev->lock);
1757 switch (dev->state) {
1758 case STATE_DEV_SETUP: // VERY odd... host died??
1759 case STATE_DEV_CONNECTED:
1760 case STATE_DEV_UNCONNECTED:
1761 next_event (dev, GADGETFS_SUSPEND);
1767 spin_unlock (&dev->lock);
1770 static struct usb_gadget_driver gadgetfs_driver = {
1771 #ifdef CONFIG_USB_GADGET_DUALSPEED
1772 .speed = USB_SPEED_HIGH,
1774 .speed = USB_SPEED_FULL,
1776 .function = (char *) driver_desc,
1777 .unbind = gadgetfs_unbind,
1778 .setup = gadgetfs_setup,
1779 .disconnect = gadgetfs_disconnect,
1780 .suspend = gadgetfs_suspend,
1783 .name = (char *) shortname,
1787 /*----------------------------------------------------------------------*/
1789 static void gadgetfs_nop(struct usb_gadget *arg) { }
1791 static int gadgetfs_probe (struct usb_gadget *gadget)
1793 CHIP = gadget->name;
1797 static struct usb_gadget_driver probe_driver = {
1798 .speed = USB_SPEED_HIGH,
1799 .unbind = gadgetfs_nop,
1800 .setup = (void *)gadgetfs_nop,
1801 .disconnect = gadgetfs_nop,
1808 /* DEVICE INITIALIZATION
1810 * fd = open ("/dev/gadget/$CHIP", O_RDWR)
1811 * status = write (fd, descriptors, sizeof descriptors)
1813 * That write establishes the device configuration, so the kernel can
1814 * bind to the controller ... guaranteeing it can handle enumeration
1815 * at all necessary speeds. Descriptor order is:
1817 * . message tag (u32, host order) ... for now, must be zero; it
1818 * would change to support features like multi-config devices
1819 * . full/low speed config ... all wTotalLength bytes (with interface,
1820 * class, altsetting, endpoint, and other descriptors)
1821 * . high speed config ... all descriptors, for high speed operation;
1822 * this one's optional except for high-speed hardware
1823 * . device descriptor
1825 * Endpoints are not yet enabled. Drivers must wait until device
1826 * configuration and interface altsetting changes create
1827 * the need to configure (or unconfigure) them.
1829 * After initialization, the device stays active for as long as that
1830 * $CHIP file is open. Events must then be read from that descriptor,
1831 * such as configuration notifications.
1834 static int is_valid_config (struct usb_config_descriptor *config)
1836 return config->bDescriptorType == USB_DT_CONFIG
1837 && config->bLength == USB_DT_CONFIG_SIZE
1838 && config->bConfigurationValue != 0
1839 && (config->bmAttributes & USB_CONFIG_ATT_ONE) != 0
1840 && (config->bmAttributes & USB_CONFIG_ATT_WAKEUP) == 0;
1841 /* FIXME if gadget->is_otg, _must_ include an otg descriptor */
1842 /* FIXME check lengths: walk to end */
1846 dev_config (struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
1848 struct dev_data *dev = fd->private_data;
1849 ssize_t value = len, length = len;
1854 if (len < (USB_DT_CONFIG_SIZE + USB_DT_DEVICE_SIZE + 4))
1857 /* we might need to change message format someday */
1858 if (copy_from_user (&tag, buf, 4))
1865 kbuf = memdup_user(buf, length);
1867 return PTR_ERR(kbuf);
1869 spin_lock_irq (&dev->lock);
1875 /* full or low speed config */
1876 dev->config = (void *) kbuf;
1877 total = le16_to_cpu(dev->config->wTotalLength);
1878 if (!is_valid_config (dev->config) || total >= length)
1883 /* optional high speed config */
1884 if (kbuf [1] == USB_DT_CONFIG) {
1885 dev->hs_config = (void *) kbuf;
1886 total = le16_to_cpu(dev->hs_config->wTotalLength);
1887 if (!is_valid_config (dev->hs_config) || total >= length)
1893 /* could support multiple configs, using another encoding! */
1895 /* device descriptor (tweaked for paranoia) */
1896 if (length != USB_DT_DEVICE_SIZE)
1898 dev->dev = (void *)kbuf;
1899 if (dev->dev->bLength != USB_DT_DEVICE_SIZE
1900 || dev->dev->bDescriptorType != USB_DT_DEVICE
1901 || dev->dev->bNumConfigurations != 1)
1903 dev->dev->bNumConfigurations = 1;
1904 dev->dev->bcdUSB = cpu_to_le16 (0x0200);
1906 /* triggers gadgetfs_bind(); then we can enumerate. */
1907 spin_unlock_irq (&dev->lock);
1908 value = usb_gadget_probe_driver(&gadgetfs_driver, gadgetfs_bind);
1913 /* at this point "good" hardware has for the first time
1914 * let the USB the host see us. alternatively, if users
1915 * unplug/replug that will clear all the error state.
1917 * note: everything running before here was guaranteed
1918 * to choke driver model style diagnostics. from here
1919 * on, they can work ... except in cleanup paths that
1920 * kick in after the ep0 descriptor is closed.
1922 fd->f_op = &ep0_io_operations;
1928 spin_unlock_irq (&dev->lock);
1929 pr_debug ("%s: %s fail %Zd, %p\n", shortname, __func__, value, dev);
1936 dev_open (struct inode *inode, struct file *fd)
1938 struct dev_data *dev = inode->i_private;
1941 spin_lock_irq(&dev->lock);
1942 if (dev->state == STATE_DEV_DISABLED) {
1944 dev->state = STATE_DEV_OPENED;
1945 fd->private_data = dev;
1949 spin_unlock_irq(&dev->lock);
1953 static const struct file_operations dev_init_operations = {
1954 .owner = THIS_MODULE,
1955 .llseek = no_llseek,
1958 .write = dev_config,
1959 .fasync = ep0_fasync,
1960 .unlocked_ioctl = dev_ioctl,
1961 .release = dev_release,
1964 /*----------------------------------------------------------------------*/
1966 /* FILESYSTEM AND SUPERBLOCK OPERATIONS
1968 * Mounting the filesystem creates a controller file, used first for
1969 * device configuration then later for event monitoring.
1973 /* FIXME PAM etc could set this security policy without mount options
1974 * if epfiles inherited ownership and permissons from ep0 ...
1977 static unsigned default_uid;
1978 static unsigned default_gid;
1979 static unsigned default_perm = S_IRUSR | S_IWUSR;
1981 module_param (default_uid, uint, 0644);
1982 module_param (default_gid, uint, 0644);
1983 module_param (default_perm, uint, 0644);
1986 static struct inode *
1987 gadgetfs_make_inode (struct super_block *sb,
1988 void *data, const struct file_operations *fops,
1991 struct inode *inode = new_inode (sb);
1994 inode->i_mode = mode;
1995 inode->i_uid = default_uid;
1996 inode->i_gid = default_gid;
1997 inode->i_atime = inode->i_mtime = inode->i_ctime
1999 inode->i_private = data;
2000 inode->i_fop = fops;
2005 /* creates in fs root directory, so non-renamable and non-linkable.
2006 * so inode and dentry are paired, until device reconfig.
2008 static struct inode *
2009 gadgetfs_create_file (struct super_block *sb, char const *name,
2010 void *data, const struct file_operations *fops,
2011 struct dentry **dentry_p)
2013 struct dentry *dentry;
2014 struct inode *inode;
2016 dentry = d_alloc_name(sb->s_root, name);
2020 inode = gadgetfs_make_inode (sb, data, fops,
2021 S_IFREG | (default_perm & S_IRWXUGO));
2026 d_add (dentry, inode);
2031 static const struct super_operations gadget_fs_operations = {
2032 .statfs = simple_statfs,
2033 .drop_inode = generic_delete_inode,
2037 gadgetfs_fill_super (struct super_block *sb, void *opts, int silent)
2039 struct inode *inode;
2041 struct dev_data *dev;
2046 /* fake probe to determine $CHIP */
2047 (void) usb_gadget_probe_driver(&probe_driver, gadgetfs_probe);
2052 sb->s_blocksize = PAGE_CACHE_SIZE;
2053 sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
2054 sb->s_magic = GADGETFS_MAGIC;
2055 sb->s_op = &gadget_fs_operations;
2056 sb->s_time_gran = 1;
2059 inode = gadgetfs_make_inode (sb,
2060 NULL, &simple_dir_operations,
2061 S_IFDIR | S_IRUGO | S_IXUGO);
2064 inode->i_op = &simple_dir_inode_operations;
2065 if (!(d = d_alloc_root (inode)))
2069 /* the ep0 file is named after the controller we expect;
2070 * user mode code can use it for sanity checks, like we do.
2077 if (!gadgetfs_create_file (sb, CHIP,
2078 dev, &dev_init_operations,
2082 /* other endpoint files are available after hardware setup,
2083 * from binding to a controller.
2098 /* "mount -t gadgetfs path /dev/gadget" ends up here */
2100 gadgetfs_get_sb (struct file_system_type *t, int flags,
2101 const char *path, void *opts, struct vfsmount *mnt)
2103 return get_sb_single (t, flags, opts, gadgetfs_fill_super, mnt);
2107 gadgetfs_kill_sb (struct super_block *sb)
2109 kill_litter_super (sb);
2111 put_dev (the_device);
2116 /*----------------------------------------------------------------------*/
2118 static struct file_system_type gadgetfs_type = {
2119 .owner = THIS_MODULE,
2121 .get_sb = gadgetfs_get_sb,
2122 .kill_sb = gadgetfs_kill_sb,
2125 /*----------------------------------------------------------------------*/
2127 static int __init init (void)
2131 status = register_filesystem (&gadgetfs_type);
2133 pr_info ("%s: %s, version " DRIVER_VERSION "\n",
2134 shortname, driver_desc);
2139 static void __exit cleanup (void)
2141 pr_debug ("unregister %s\n", shortname);
2142 unregister_filesystem (&gadgetfs_type);
2144 module_exit (cleanup);