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)) {
390 mutex_unlock(&data->lock);
393 DBG (data->dev, "%s halt\n", data->name);
394 spin_lock_irq (&data->dev->lock);
395 if (likely (data->ep != NULL))
396 usb_ep_set_halt (data->ep);
397 spin_unlock_irq (&data->dev->lock);
398 mutex_unlock(&data->lock);
402 /* FIXME readahead for O_NONBLOCK and poll(); careful with ZLPs */
405 kbuf = kmalloc (len, GFP_KERNEL);
406 if (unlikely (!kbuf))
409 value = ep_io (data, kbuf, len);
410 VDEBUG (data->dev, "%s read %zu OUT, status %d\n",
411 data->name, len, (int) value);
412 if (value >= 0 && copy_to_user (buf, kbuf, value))
416 mutex_unlock(&data->lock);
421 /* handle a synchronous IN bulk/intr/iso transfer */
423 ep_write (struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
425 struct ep_data *data = fd->private_data;
429 if ((value = get_ready_ep (fd->f_flags, data)) < 0)
432 /* halt any endpoint by doing a "wrong direction" i/o call */
433 if (!usb_endpoint_dir_in(&data->desc)) {
434 if (usb_endpoint_xfer_isoc(&data->desc))
436 DBG (data->dev, "%s halt\n", data->name);
437 spin_lock_irq (&data->dev->lock);
438 if (likely (data->ep != NULL))
439 usb_ep_set_halt (data->ep);
440 spin_unlock_irq (&data->dev->lock);
441 mutex_unlock(&data->lock);
445 /* FIXME writebehind for O_NONBLOCK and poll(), qlen = 1 */
448 kbuf = kmalloc (len, GFP_KERNEL);
451 if (copy_from_user (kbuf, buf, len)) {
456 value = ep_io (data, kbuf, len);
457 VDEBUG (data->dev, "%s write %zu IN, status %d\n",
458 data->name, len, (int) value);
460 mutex_unlock(&data->lock);
466 ep_release (struct inode *inode, struct file *fd)
468 struct ep_data *data = fd->private_data;
471 value = mutex_lock_interruptible(&data->lock);
475 /* clean up if this can be reopened */
476 if (data->state != STATE_EP_UNBOUND) {
477 data->state = STATE_EP_DISABLED;
478 data->desc.bDescriptorType = 0;
479 data->hs_desc.bDescriptorType = 0;
480 usb_ep_disable(data->ep);
482 mutex_unlock(&data->lock);
487 static long ep_ioctl(struct file *fd, unsigned code, unsigned long value)
489 struct ep_data *data = fd->private_data;
492 if ((status = get_ready_ep (fd->f_flags, data)) < 0)
495 spin_lock_irq (&data->dev->lock);
496 if (likely (data->ep != NULL)) {
498 case GADGETFS_FIFO_STATUS:
499 status = usb_ep_fifo_status (data->ep);
501 case GADGETFS_FIFO_FLUSH:
502 usb_ep_fifo_flush (data->ep);
504 case GADGETFS_CLEAR_HALT:
505 status = usb_ep_clear_halt (data->ep);
512 spin_unlock_irq (&data->dev->lock);
513 mutex_unlock(&data->lock);
517 /*----------------------------------------------------------------------*/
519 /* ASYNCHRONOUS ENDPOINT I/O OPERATIONS (bulk/intr/iso) */
522 struct usb_request *req;
523 struct ep_data *epdata;
525 const struct iovec *iv;
526 unsigned long nr_segs;
530 static int ep_aio_cancel(struct kiocb *iocb, struct io_event *e)
532 struct kiocb_priv *priv = iocb->private;
533 struct ep_data *epdata;
537 epdata = priv->epdata;
538 // spin_lock(&epdata->dev->lock);
539 kiocbSetCancelled(iocb);
540 if (likely(epdata && epdata->ep && priv->req))
541 value = usb_ep_dequeue (epdata->ep, priv->req);
544 // spin_unlock(&epdata->dev->lock);
551 static ssize_t ep_aio_read_retry(struct kiocb *iocb)
553 struct kiocb_priv *priv = iocb->private;
558 /* we "retry" to get the right mm context for this: */
560 /* copy stuff into user buffers */
561 total = priv->actual;
564 for (i=0; i < priv->nr_segs; i++) {
565 ssize_t this = min((ssize_t)(priv->iv[i].iov_len), total);
567 if (copy_to_user(priv->iv[i].iov_base, to_copy, this)) {
584 static void ep_aio_complete(struct usb_ep *ep, struct usb_request *req)
586 struct kiocb *iocb = req->context;
587 struct kiocb_priv *priv = iocb->private;
588 struct ep_data *epdata = priv->epdata;
590 /* lock against disconnect (and ideally, cancel) */
591 spin_lock(&epdata->dev->lock);
595 /* if this was a write or a read returning no data then we
596 * don't need to copy anything to userspace, so we can
597 * complete the aio request immediately.
599 if (priv->iv == NULL || unlikely(req->actual == 0)) {
602 iocb->private = NULL;
603 /* aio_complete() reports bytes-transferred _and_ faults */
604 aio_complete(iocb, req->actual ? req->actual : req->status,
607 /* retry() won't report both; so we hide some faults */
608 if (unlikely(0 != req->status))
609 DBG(epdata->dev, "%s fault %d len %d\n",
610 ep->name, req->status, req->actual);
612 priv->buf = req->buf;
613 priv->actual = req->actual;
616 spin_unlock(&epdata->dev->lock);
618 usb_ep_free_request(ep, req);
627 struct ep_data *epdata,
628 const struct iovec *iv,
629 unsigned long nr_segs
632 struct kiocb_priv *priv;
633 struct usb_request *req;
636 priv = kmalloc(sizeof *priv, GFP_KERNEL);
643 iocb->private = priv;
645 priv->nr_segs = nr_segs;
647 value = get_ready_ep(iocb->ki_filp->f_flags, epdata);
648 if (unlikely(value < 0)) {
653 iocb->ki_cancel = ep_aio_cancel;
655 priv->epdata = epdata;
658 /* each kiocb is coupled to one usb_request, but we can't
659 * allocate or submit those if the host disconnected.
661 spin_lock_irq(&epdata->dev->lock);
662 if (likely(epdata->ep)) {
663 req = usb_ep_alloc_request(epdata->ep, GFP_ATOMIC);
668 req->complete = ep_aio_complete;
670 value = usb_ep_queue(epdata->ep, req, GFP_ATOMIC);
671 if (unlikely(0 != value))
672 usb_ep_free_request(epdata->ep, req);
677 spin_unlock_irq(&epdata->dev->lock);
679 mutex_unlock(&epdata->lock);
681 if (unlikely(value)) {
685 value = (iv ? -EIOCBRETRY : -EIOCBQUEUED);
690 ep_aio_read(struct kiocb *iocb, const struct iovec *iov,
691 unsigned long nr_segs, loff_t o)
693 struct ep_data *epdata = iocb->ki_filp->private_data;
696 if (unlikely(usb_endpoint_dir_in(&epdata->desc)))
699 buf = kmalloc(iocb->ki_left, GFP_KERNEL);
703 iocb->ki_retry = ep_aio_read_retry;
704 return ep_aio_rwtail(iocb, buf, iocb->ki_left, epdata, iov, nr_segs);
708 ep_aio_write(struct kiocb *iocb, const struct iovec *iov,
709 unsigned long nr_segs, loff_t o)
711 struct ep_data *epdata = iocb->ki_filp->private_data;
716 if (unlikely(!usb_endpoint_dir_in(&epdata->desc)))
719 buf = kmalloc(iocb->ki_left, GFP_KERNEL);
723 for (i=0; i < nr_segs; i++) {
724 if (unlikely(copy_from_user(&buf[len], iov[i].iov_base,
725 iov[i].iov_len) != 0)) {
729 len += iov[i].iov_len;
731 return ep_aio_rwtail(iocb, buf, len, epdata, NULL, 0);
734 /*----------------------------------------------------------------------*/
736 /* used after endpoint configuration */
737 static const struct file_operations ep_io_operations = {
738 .owner = THIS_MODULE,
743 .unlocked_ioctl = ep_ioctl,
744 .release = ep_release,
746 .aio_read = ep_aio_read,
747 .aio_write = ep_aio_write,
750 /* ENDPOINT INITIALIZATION
752 * fd = open ("/dev/gadget/$ENDPOINT", O_RDWR)
753 * status = write (fd, descriptors, sizeof descriptors)
755 * That write establishes the endpoint configuration, configuring
756 * the controller to process bulk, interrupt, or isochronous transfers
757 * at the right maxpacket size, and so on.
759 * The descriptors are message type 1, identified by a host order u32
760 * at the beginning of what's written. Descriptor order is: full/low
761 * speed descriptor, then optional high speed descriptor.
764 ep_config (struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
766 struct ep_data *data = fd->private_data;
769 int value, length = len;
771 value = mutex_lock_interruptible(&data->lock);
775 if (data->state != STATE_EP_READY) {
781 if (len < USB_DT_ENDPOINT_SIZE + 4)
784 /* we might need to change message format someday */
785 if (copy_from_user (&tag, buf, 4)) {
789 DBG(data->dev, "config %s, bad tag %d\n", data->name, tag);
795 /* NOTE: audio endpoint extensions not accepted here;
796 * just don't include the extra bytes.
799 /* full/low speed descriptor, then high speed */
800 if (copy_from_user (&data->desc, buf, USB_DT_ENDPOINT_SIZE)) {
803 if (data->desc.bLength != USB_DT_ENDPOINT_SIZE
804 || data->desc.bDescriptorType != USB_DT_ENDPOINT)
806 if (len != USB_DT_ENDPOINT_SIZE) {
807 if (len != 2 * USB_DT_ENDPOINT_SIZE)
809 if (copy_from_user (&data->hs_desc, buf + USB_DT_ENDPOINT_SIZE,
810 USB_DT_ENDPOINT_SIZE)) {
813 if (data->hs_desc.bLength != USB_DT_ENDPOINT_SIZE
814 || data->hs_desc.bDescriptorType
815 != USB_DT_ENDPOINT) {
816 DBG(data->dev, "config %s, bad hs length or type\n",
822 spin_lock_irq (&data->dev->lock);
823 if (data->dev->state == STATE_DEV_UNBOUND) {
826 } else if ((ep = data->ep) == NULL) {
830 switch (data->dev->gadget->speed) {
833 value = usb_ep_enable (ep, &data->desc);
835 data->state = STATE_EP_ENABLED;
837 #ifdef CONFIG_USB_GADGET_DUALSPEED
839 /* fails if caller didn't provide that descriptor... */
840 value = usb_ep_enable (ep, &data->hs_desc);
842 data->state = STATE_EP_ENABLED;
846 DBG(data->dev, "unconnected, %s init abandoned\n",
851 fd->f_op = &ep_io_operations;
855 spin_unlock_irq (&data->dev->lock);
858 data->desc.bDescriptorType = 0;
859 data->hs_desc.bDescriptorType = 0;
861 mutex_unlock(&data->lock);
872 ep_open (struct inode *inode, struct file *fd)
874 struct ep_data *data = inode->i_private;
877 if (mutex_lock_interruptible(&data->lock) != 0)
879 spin_lock_irq (&data->dev->lock);
880 if (data->dev->state == STATE_DEV_UNBOUND)
882 else if (data->state == STATE_EP_DISABLED) {
884 data->state = STATE_EP_READY;
886 fd->private_data = data;
887 VDEBUG (data->dev, "%s ready\n", data->name);
889 DBG (data->dev, "%s state %d\n",
890 data->name, data->state);
891 spin_unlock_irq (&data->dev->lock);
892 mutex_unlock(&data->lock);
896 /* used before endpoint configuration */
897 static const struct file_operations ep_config_operations = {
898 .owner = THIS_MODULE,
903 .release = ep_release,
906 /*----------------------------------------------------------------------*/
908 /* EP0 IMPLEMENTATION can be partly in userspace.
910 * Drivers that use this facility receive various events, including
911 * control requests the kernel doesn't handle. Drivers that don't
912 * use this facility may be too simple-minded for real applications.
915 static inline void ep0_readable (struct dev_data *dev)
917 wake_up (&dev->wait);
918 kill_fasync (&dev->fasync, SIGIO, POLL_IN);
921 static void clean_req (struct usb_ep *ep, struct usb_request *req)
923 struct dev_data *dev = ep->driver_data;
925 if (req->buf != dev->rbuf) {
927 req->buf = dev->rbuf;
928 req->dma = DMA_ADDR_INVALID;
930 req->complete = epio_complete;
931 dev->setup_out_ready = 0;
934 static void ep0_complete (struct usb_ep *ep, struct usb_request *req)
936 struct dev_data *dev = ep->driver_data;
940 /* for control OUT, data must still get to userspace */
941 spin_lock_irqsave(&dev->lock, flags);
942 if (!dev->setup_in) {
943 dev->setup_out_error = (req->status != 0);
944 if (!dev->setup_out_error)
946 dev->setup_out_ready = 1;
950 /* clean up as appropriate */
951 if (free && req->buf != &dev->rbuf)
953 req->complete = epio_complete;
954 spin_unlock_irqrestore(&dev->lock, flags);
957 static int setup_req (struct usb_ep *ep, struct usb_request *req, u16 len)
959 struct dev_data *dev = ep->driver_data;
961 if (dev->setup_out_ready) {
962 DBG (dev, "ep0 request busy!\n");
965 if (len > sizeof (dev->rbuf))
966 req->buf = kmalloc(len, GFP_ATOMIC);
967 if (req->buf == NULL) {
968 req->buf = dev->rbuf;
971 req->complete = ep0_complete;
978 ep0_read (struct file *fd, char __user *buf, size_t len, loff_t *ptr)
980 struct dev_data *dev = fd->private_data;
982 enum ep0_state state;
984 spin_lock_irq (&dev->lock);
986 /* report fd mode change before acting on it */
987 if (dev->setup_abort) {
988 dev->setup_abort = 0;
993 /* control DATA stage */
994 if ((state = dev->state) == STATE_DEV_SETUP) {
996 if (dev->setup_in) { /* stall IN */
997 VDEBUG(dev, "ep0in stall\n");
998 (void) usb_ep_set_halt (dev->gadget->ep0);
1000 dev->state = STATE_DEV_CONNECTED;
1002 } else if (len == 0) { /* ack SET_CONFIGURATION etc */
1003 struct usb_ep *ep = dev->gadget->ep0;
1004 struct usb_request *req = dev->req;
1006 if ((retval = setup_req (ep, req, 0)) == 0)
1007 retval = usb_ep_queue (ep, req, GFP_ATOMIC);
1008 dev->state = STATE_DEV_CONNECTED;
1010 /* assume that was SET_CONFIGURATION */
1011 if (dev->current_config) {
1014 if (gadget_is_dualspeed(dev->gadget)
1015 && (dev->gadget->speed
1017 power = dev->hs_config->bMaxPower;
1019 power = dev->config->bMaxPower;
1020 usb_gadget_vbus_draw(dev->gadget, 2 * power);
1023 } else { /* collect OUT data */
1024 if ((fd->f_flags & O_NONBLOCK) != 0
1025 && !dev->setup_out_ready) {
1029 spin_unlock_irq (&dev->lock);
1030 retval = wait_event_interruptible (dev->wait,
1031 dev->setup_out_ready != 0);
1033 /* FIXME state could change from under us */
1034 spin_lock_irq (&dev->lock);
1038 if (dev->state != STATE_DEV_SETUP) {
1039 retval = -ECANCELED;
1042 dev->state = STATE_DEV_CONNECTED;
1044 if (dev->setup_out_error)
1047 len = min (len, (size_t)dev->req->actual);
1048 // FIXME don't call this with the spinlock held ...
1049 if (copy_to_user (buf, dev->req->buf, len))
1051 clean_req (dev->gadget->ep0, dev->req);
1052 /* NOTE userspace can't yet choose to stall */
1058 /* else normal: return event data */
1059 if (len < sizeof dev->event [0]) {
1063 len -= len % sizeof (struct usb_gadgetfs_event);
1064 dev->usermode_setup = 1;
1067 /* return queued events right away */
1068 if (dev->ev_next != 0) {
1071 n = len / sizeof (struct usb_gadgetfs_event);
1072 if (dev->ev_next < n)
1075 /* ep0 i/o has special semantics during STATE_DEV_SETUP */
1076 for (i = 0; i < n; i++) {
1077 if (dev->event [i].type == GADGETFS_SETUP) {
1078 dev->state = STATE_DEV_SETUP;
1083 spin_unlock_irq (&dev->lock);
1084 len = n * sizeof (struct usb_gadgetfs_event);
1085 if (copy_to_user (buf, &dev->event, len))
1090 /* NOTE this doesn't guard against broken drivers;
1091 * concurrent ep0 readers may lose events.
1093 spin_lock_irq (&dev->lock);
1094 if (dev->ev_next > n) {
1095 memmove(&dev->event[0], &dev->event[n],
1096 sizeof (struct usb_gadgetfs_event)
1097 * (dev->ev_next - n));
1100 spin_unlock_irq (&dev->lock);
1104 if (fd->f_flags & O_NONBLOCK) {
1111 DBG (dev, "fail %s, state %d\n", __func__, state);
1114 case STATE_DEV_UNCONNECTED:
1115 case STATE_DEV_CONNECTED:
1116 spin_unlock_irq (&dev->lock);
1117 DBG (dev, "%s wait\n", __func__);
1119 /* wait for events */
1120 retval = wait_event_interruptible (dev->wait,
1124 spin_lock_irq (&dev->lock);
1129 spin_unlock_irq (&dev->lock);
1133 static struct usb_gadgetfs_event *
1134 next_event (struct dev_data *dev, enum usb_gadgetfs_event_type type)
1136 struct usb_gadgetfs_event *event;
1140 /* these events purge the queue */
1141 case GADGETFS_DISCONNECT:
1142 if (dev->state == STATE_DEV_SETUP)
1143 dev->setup_abort = 1;
1145 case GADGETFS_CONNECT:
1148 case GADGETFS_SETUP: /* previous request timed out */
1149 case GADGETFS_SUSPEND: /* same effect */
1150 /* these events can't be repeated */
1151 for (i = 0; i != dev->ev_next; i++) {
1152 if (dev->event [i].type != type)
1154 DBG(dev, "discard old event[%d] %d\n", i, type);
1156 if (i == dev->ev_next)
1158 /* indices start at zero, for simplicity */
1159 memmove (&dev->event [i], &dev->event [i + 1],
1160 sizeof (struct usb_gadgetfs_event)
1161 * (dev->ev_next - i));
1167 VDEBUG(dev, "event[%d] = %d\n", dev->ev_next, type);
1168 event = &dev->event [dev->ev_next++];
1169 BUG_ON (dev->ev_next > N_EVENT);
1170 memset (event, 0, sizeof *event);
1176 ep0_write (struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
1178 struct dev_data *dev = fd->private_data;
1179 ssize_t retval = -ESRCH;
1181 spin_lock_irq (&dev->lock);
1183 /* report fd mode change before acting on it */
1184 if (dev->setup_abort) {
1185 dev->setup_abort = 0;
1188 /* data and/or status stage for control request */
1189 } else if (dev->state == STATE_DEV_SETUP) {
1191 /* IN DATA+STATUS caller makes len <= wLength */
1192 if (dev->setup_in) {
1193 retval = setup_req (dev->gadget->ep0, dev->req, len);
1195 dev->state = STATE_DEV_CONNECTED;
1196 spin_unlock_irq (&dev->lock);
1197 if (copy_from_user (dev->req->buf, buf, len))
1200 if (len < dev->setup_wLength)
1202 retval = usb_ep_queue (
1203 dev->gadget->ep0, dev->req,
1207 spin_lock_irq (&dev->lock);
1208 clean_req (dev->gadget->ep0, dev->req);
1209 spin_unlock_irq (&dev->lock);
1216 /* can stall some OUT transfers */
1217 } else if (dev->setup_can_stall) {
1218 VDEBUG(dev, "ep0out stall\n");
1219 (void) usb_ep_set_halt (dev->gadget->ep0);
1221 dev->state = STATE_DEV_CONNECTED;
1223 DBG(dev, "bogus ep0out stall!\n");
1226 DBG (dev, "fail %s, state %d\n", __func__, dev->state);
1228 spin_unlock_irq (&dev->lock);
1233 ep0_fasync (int f, struct file *fd, int on)
1235 struct dev_data *dev = fd->private_data;
1236 // caller must F_SETOWN before signal delivery happens
1237 VDEBUG (dev, "%s %s\n", __func__, on ? "on" : "off");
1238 return fasync_helper (f, fd, on, &dev->fasync);
1241 static struct usb_gadget_driver gadgetfs_driver;
1244 dev_release (struct inode *inode, struct file *fd)
1246 struct dev_data *dev = fd->private_data;
1248 /* closing ep0 === shutdown all */
1250 usb_gadget_unregister_driver (&gadgetfs_driver);
1252 /* at this point "good" hardware has disconnected the
1253 * device from USB; the host won't see it any more.
1254 * alternatively, all host requests will time out.
1261 /* other endpoints were all decoupled from this device */
1262 spin_lock_irq(&dev->lock);
1263 dev->state = STATE_DEV_DISABLED;
1264 spin_unlock_irq(&dev->lock);
1269 ep0_poll (struct file *fd, poll_table *wait)
1271 struct dev_data *dev = fd->private_data;
1274 poll_wait(fd, &dev->wait, wait);
1276 spin_lock_irq (&dev->lock);
1278 /* report fd mode change before acting on it */
1279 if (dev->setup_abort) {
1280 dev->setup_abort = 0;
1285 if (dev->state == STATE_DEV_SETUP) {
1286 if (dev->setup_in || dev->setup_can_stall)
1289 if (dev->ev_next != 0)
1293 spin_unlock_irq(&dev->lock);
1297 static long dev_ioctl (struct file *fd, unsigned code, unsigned long value)
1299 struct dev_data *dev = fd->private_data;
1300 struct usb_gadget *gadget = dev->gadget;
1303 if (gadget->ops->ioctl)
1304 ret = gadget->ops->ioctl (gadget, code, value);
1309 /* used after device configuration */
1310 static const struct file_operations ep0_io_operations = {
1311 .owner = THIS_MODULE,
1312 .llseek = no_llseek,
1316 .fasync = ep0_fasync,
1318 .unlocked_ioctl = dev_ioctl,
1319 .release = dev_release,
1322 /*----------------------------------------------------------------------*/
1324 /* The in-kernel gadget driver handles most ep0 issues, in particular
1325 * enumerating the single configuration (as provided from user space).
1327 * Unrecognized ep0 requests may be handled in user space.
1330 #ifdef CONFIG_USB_GADGET_DUALSPEED
1331 static void make_qualifier (struct dev_data *dev)
1333 struct usb_qualifier_descriptor qual;
1334 struct usb_device_descriptor *desc;
1336 qual.bLength = sizeof qual;
1337 qual.bDescriptorType = USB_DT_DEVICE_QUALIFIER;
1338 qual.bcdUSB = cpu_to_le16 (0x0200);
1341 qual.bDeviceClass = desc->bDeviceClass;
1342 qual.bDeviceSubClass = desc->bDeviceSubClass;
1343 qual.bDeviceProtocol = desc->bDeviceProtocol;
1345 /* assumes ep0 uses the same value for both speeds ... */
1346 qual.bMaxPacketSize0 = desc->bMaxPacketSize0;
1348 qual.bNumConfigurations = 1;
1351 memcpy (dev->rbuf, &qual, sizeof qual);
1356 config_buf (struct dev_data *dev, u8 type, unsigned index)
1361 /* only one configuration */
1365 if (gadget_is_dualspeed(dev->gadget)) {
1366 hs = (dev->gadget->speed == USB_SPEED_HIGH);
1367 if (type == USB_DT_OTHER_SPEED_CONFIG)
1371 dev->req->buf = dev->hs_config;
1372 len = le16_to_cpu(dev->hs_config->wTotalLength);
1374 dev->req->buf = dev->config;
1375 len = le16_to_cpu(dev->config->wTotalLength);
1377 ((u8 *)dev->req->buf) [1] = type;
1382 gadgetfs_setup (struct usb_gadget *gadget, const struct usb_ctrlrequest *ctrl)
1384 struct dev_data *dev = get_gadget_data (gadget);
1385 struct usb_request *req = dev->req;
1386 int value = -EOPNOTSUPP;
1387 struct usb_gadgetfs_event *event;
1388 u16 w_value = le16_to_cpu(ctrl->wValue);
1389 u16 w_length = le16_to_cpu(ctrl->wLength);
1391 spin_lock (&dev->lock);
1392 dev->setup_abort = 0;
1393 if (dev->state == STATE_DEV_UNCONNECTED) {
1394 if (gadget_is_dualspeed(gadget)
1395 && gadget->speed == USB_SPEED_HIGH
1396 && dev->hs_config == NULL) {
1397 spin_unlock(&dev->lock);
1398 ERROR (dev, "no high speed config??\n");
1402 dev->state = STATE_DEV_CONNECTED;
1403 dev->dev->bMaxPacketSize0 = gadget->ep0->maxpacket;
1405 INFO (dev, "connected\n");
1406 event = next_event (dev, GADGETFS_CONNECT);
1407 event->u.speed = gadget->speed;
1410 /* host may have given up waiting for response. we can miss control
1411 * requests handled lower down (device/endpoint status and features);
1412 * then ep0_{read,write} will report the wrong status. controller
1413 * driver will have aborted pending i/o.
1415 } else if (dev->state == STATE_DEV_SETUP)
1416 dev->setup_abort = 1;
1418 req->buf = dev->rbuf;
1419 req->dma = DMA_ADDR_INVALID;
1420 req->context = NULL;
1421 value = -EOPNOTSUPP;
1422 switch (ctrl->bRequest) {
1424 case USB_REQ_GET_DESCRIPTOR:
1425 if (ctrl->bRequestType != USB_DIR_IN)
1427 switch (w_value >> 8) {
1430 value = min (w_length, (u16) sizeof *dev->dev);
1431 req->buf = dev->dev;
1433 #ifdef CONFIG_USB_GADGET_DUALSPEED
1434 case USB_DT_DEVICE_QUALIFIER:
1435 if (!dev->hs_config)
1437 value = min (w_length, (u16)
1438 sizeof (struct usb_qualifier_descriptor));
1439 make_qualifier (dev);
1441 case USB_DT_OTHER_SPEED_CONFIG:
1445 value = config_buf (dev,
1449 value = min (w_length, (u16) value);
1454 default: // all others are errors
1459 /* currently one config, two speeds */
1460 case USB_REQ_SET_CONFIGURATION:
1461 if (ctrl->bRequestType != 0)
1463 if (0 == (u8) w_value) {
1465 dev->current_config = 0;
1466 usb_gadget_vbus_draw(gadget, 8 /* mA */ );
1467 // user mode expected to disable endpoints
1471 if (gadget_is_dualspeed(gadget)
1472 && gadget->speed == USB_SPEED_HIGH) {
1473 config = dev->hs_config->bConfigurationValue;
1474 power = dev->hs_config->bMaxPower;
1476 config = dev->config->bConfigurationValue;
1477 power = dev->config->bMaxPower;
1480 if (config == (u8) w_value) {
1482 dev->current_config = config;
1483 usb_gadget_vbus_draw(gadget, 2 * power);
1487 /* report SET_CONFIGURATION like any other control request,
1488 * except that usermode may not stall this. the next
1489 * request mustn't be allowed start until this finishes:
1490 * endpoints and threads set up, etc.
1492 * NOTE: older PXA hardware (before PXA 255: without UDCCFR)
1493 * has bad/racey automagic that prevents synchronizing here.
1494 * even kernel mode drivers often miss them.
1497 INFO (dev, "configuration #%d\n", dev->current_config);
1498 if (dev->usermode_setup) {
1499 dev->setup_can_stall = 0;
1505 #ifndef CONFIG_USB_GADGET_PXA25X
1506 /* PXA automagically handles this request too */
1507 case USB_REQ_GET_CONFIGURATION:
1508 if (ctrl->bRequestType != 0x80)
1510 *(u8 *)req->buf = dev->current_config;
1511 value = min (w_length, (u16) 1);
1517 VDEBUG (dev, "%s req%02x.%02x v%04x i%04x l%d\n",
1518 dev->usermode_setup ? "delegate" : "fail",
1519 ctrl->bRequestType, ctrl->bRequest,
1520 w_value, le16_to_cpu(ctrl->wIndex), w_length);
1522 /* if there's an ep0 reader, don't stall */
1523 if (dev->usermode_setup) {
1524 dev->setup_can_stall = 1;
1526 dev->setup_in = (ctrl->bRequestType & USB_DIR_IN)
1528 dev->setup_wLength = w_length;
1529 dev->setup_out_ready = 0;
1530 dev->setup_out_error = 0;
1533 /* read DATA stage for OUT right away */
1534 if (unlikely (!dev->setup_in && w_length)) {
1535 value = setup_req (gadget->ep0, dev->req,
1539 value = usb_ep_queue (gadget->ep0, dev->req,
1542 clean_req (gadget->ep0, dev->req);
1546 /* we can't currently stall these */
1547 dev->setup_can_stall = 0;
1550 /* state changes when reader collects event */
1551 event = next_event (dev, GADGETFS_SETUP);
1552 event->u.setup = *ctrl;
1554 spin_unlock (&dev->lock);
1559 /* proceed with data transfer and status phases? */
1560 if (value >= 0 && dev->state != STATE_DEV_SETUP) {
1561 req->length = value;
1562 req->zero = value < w_length;
1563 value = usb_ep_queue (gadget->ep0, req, GFP_ATOMIC);
1565 DBG (dev, "ep_queue --> %d\n", value);
1570 /* device stalls when value < 0 */
1571 spin_unlock (&dev->lock);
1575 static void destroy_ep_files (struct dev_data *dev)
1577 struct list_head *entry, *tmp;
1579 DBG (dev, "%s %d\n", __func__, dev->state);
1581 /* dev->state must prevent interference */
1583 spin_lock_irq (&dev->lock);
1584 list_for_each_safe (entry, tmp, &dev->epfiles) {
1586 struct inode *parent;
1587 struct dentry *dentry;
1589 /* break link to FS */
1590 ep = list_entry (entry, struct ep_data, epfiles);
1591 list_del_init (&ep->epfiles);
1592 dentry = ep->dentry;
1594 parent = dentry->d_parent->d_inode;
1596 /* break link to controller */
1597 if (ep->state == STATE_EP_ENABLED)
1598 (void) usb_ep_disable (ep->ep);
1599 ep->state = STATE_EP_UNBOUND;
1600 usb_ep_free_request (ep->ep, ep->req);
1602 wake_up (&ep->wait);
1605 spin_unlock_irq (&dev->lock);
1607 /* break link to dcache */
1608 mutex_lock (&parent->i_mutex);
1611 mutex_unlock (&parent->i_mutex);
1613 /* fds may still be open */
1616 spin_unlock_irq (&dev->lock);
1620 static struct inode *
1621 gadgetfs_create_file (struct super_block *sb, char const *name,
1622 void *data, const struct file_operations *fops,
1623 struct dentry **dentry_p);
1625 static int activate_ep_files (struct dev_data *dev)
1628 struct ep_data *data;
1630 gadget_for_each_ep (ep, dev->gadget) {
1632 data = kzalloc(sizeof(*data), GFP_KERNEL);
1635 data->state = STATE_EP_DISABLED;
1636 mutex_init(&data->lock);
1637 init_waitqueue_head (&data->wait);
1639 strncpy (data->name, ep->name, sizeof (data->name) - 1);
1640 atomic_set (&data->count, 1);
1645 ep->driver_data = data;
1647 data->req = usb_ep_alloc_request (ep, GFP_KERNEL);
1651 data->inode = gadgetfs_create_file (dev->sb, data->name,
1652 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;
1696 gadgetfs_bind (struct usb_gadget *gadget)
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;
1711 dev->dev->bMaxPacketSize0 = gadget->ep0->maxpacket;
1713 /* preallocate control response and buffer */
1714 dev->req = usb_ep_alloc_request (gadget->ep0, GFP_KERNEL);
1717 dev->req->context = NULL;
1718 dev->req->complete = epio_complete;
1720 if (activate_ep_files (dev) < 0)
1723 INFO (dev, "bound to %s driver\n", gadget->name);
1724 spin_lock_irq(&dev->lock);
1725 dev->state = STATE_DEV_UNCONNECTED;
1726 spin_unlock_irq(&dev->lock);
1731 gadgetfs_unbind (gadget);
1736 gadgetfs_disconnect (struct usb_gadget *gadget)
1738 struct dev_data *dev = get_gadget_data (gadget);
1740 spin_lock (&dev->lock);
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 (&dev->lock);
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 #ifdef CONFIG_USB_GADGET_DUALSPEED
1774 .speed = USB_SPEED_HIGH,
1776 .speed = USB_SPEED_FULL,
1778 .function = (char *) driver_desc,
1779 .unbind = gadgetfs_unbind,
1780 .setup = gadgetfs_setup,
1781 .disconnect = gadgetfs_disconnect,
1782 .suspend = gadgetfs_suspend,
1785 .name = (char *) shortname,
1789 /*----------------------------------------------------------------------*/
1791 static void gadgetfs_nop(struct usb_gadget *arg) { }
1793 static int gadgetfs_probe (struct usb_gadget *gadget)
1795 CHIP = gadget->name;
1799 static struct usb_gadget_driver probe_driver = {
1800 .speed = USB_SPEED_HIGH,
1801 .unbind = gadgetfs_nop,
1802 .setup = (void *)gadgetfs_nop,
1803 .disconnect = gadgetfs_nop,
1810 /* DEVICE INITIALIZATION
1812 * fd = open ("/dev/gadget/$CHIP", O_RDWR)
1813 * status = write (fd, descriptors, sizeof descriptors)
1815 * That write establishes the device configuration, so the kernel can
1816 * bind to the controller ... guaranteeing it can handle enumeration
1817 * at all necessary speeds. Descriptor order is:
1819 * . message tag (u32, host order) ... for now, must be zero; it
1820 * would change to support features like multi-config devices
1821 * . full/low speed config ... all wTotalLength bytes (with interface,
1822 * class, altsetting, endpoint, and other descriptors)
1823 * . high speed config ... all descriptors, for high speed operation;
1824 * this one's optional except for high-speed hardware
1825 * . device descriptor
1827 * Endpoints are not yet enabled. Drivers must wait until device
1828 * configuration and interface altsetting changes create
1829 * the need to configure (or unconfigure) them.
1831 * After initialization, the device stays active for as long as that
1832 * $CHIP file is open. Events must then be read from that descriptor,
1833 * such as configuration notifications.
1836 static int is_valid_config (struct usb_config_descriptor *config)
1838 return config->bDescriptorType == USB_DT_CONFIG
1839 && config->bLength == USB_DT_CONFIG_SIZE
1840 && config->bConfigurationValue != 0
1841 && (config->bmAttributes & USB_CONFIG_ATT_ONE) != 0
1842 && (config->bmAttributes & USB_CONFIG_ATT_WAKEUP) == 0;
1843 /* FIXME if gadget->is_otg, _must_ include an otg descriptor */
1844 /* FIXME check lengths: walk to end */
1848 dev_config (struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
1850 struct dev_data *dev = fd->private_data;
1851 ssize_t value = len, length = len;
1856 if (len < (USB_DT_CONFIG_SIZE + USB_DT_DEVICE_SIZE + 4))
1859 /* we might need to change message format someday */
1860 if (copy_from_user (&tag, buf, 4))
1867 kbuf = memdup_user(buf, length);
1869 return PTR_ERR(kbuf);
1871 spin_lock_irq (&dev->lock);
1877 /* full or low speed config */
1878 dev->config = (void *) kbuf;
1879 total = le16_to_cpu(dev->config->wTotalLength);
1880 if (!is_valid_config (dev->config) || total >= length)
1885 /* optional high speed config */
1886 if (kbuf [1] == USB_DT_CONFIG) {
1887 dev->hs_config = (void *) kbuf;
1888 total = le16_to_cpu(dev->hs_config->wTotalLength);
1889 if (!is_valid_config (dev->hs_config) || total >= length)
1895 /* could support multiple configs, using another encoding! */
1897 /* device descriptor (tweaked for paranoia) */
1898 if (length != USB_DT_DEVICE_SIZE)
1900 dev->dev = (void *)kbuf;
1901 if (dev->dev->bLength != USB_DT_DEVICE_SIZE
1902 || dev->dev->bDescriptorType != USB_DT_DEVICE
1903 || dev->dev->bNumConfigurations != 1)
1905 dev->dev->bNumConfigurations = 1;
1906 dev->dev->bcdUSB = cpu_to_le16 (0x0200);
1908 /* triggers gadgetfs_bind(); then we can enumerate. */
1909 spin_unlock_irq (&dev->lock);
1910 value = usb_gadget_probe_driver(&gadgetfs_driver, gadgetfs_bind);
1915 /* at this point "good" hardware has for the first time
1916 * let the USB the host see us. alternatively, if users
1917 * unplug/replug that will clear all the error state.
1919 * note: everything running before here was guaranteed
1920 * to choke driver model style diagnostics. from here
1921 * on, they can work ... except in cleanup paths that
1922 * kick in after the ep0 descriptor is closed.
1924 fd->f_op = &ep0_io_operations;
1930 spin_unlock_irq (&dev->lock);
1931 pr_debug ("%s: %s fail %Zd, %p\n", shortname, __func__, value, dev);
1938 dev_open (struct inode *inode, struct file *fd)
1940 struct dev_data *dev = inode->i_private;
1943 spin_lock_irq(&dev->lock);
1944 if (dev->state == STATE_DEV_DISABLED) {
1946 dev->state = STATE_DEV_OPENED;
1947 fd->private_data = dev;
1951 spin_unlock_irq(&dev->lock);
1955 static const struct file_operations dev_init_operations = {
1956 .owner = THIS_MODULE,
1957 .llseek = no_llseek,
1960 .write = dev_config,
1961 .fasync = ep0_fasync,
1962 .unlocked_ioctl = dev_ioctl,
1963 .release = dev_release,
1966 /*----------------------------------------------------------------------*/
1968 /* FILESYSTEM AND SUPERBLOCK OPERATIONS
1970 * Mounting the filesystem creates a controller file, used first for
1971 * device configuration then later for event monitoring.
1975 /* FIXME PAM etc could set this security policy without mount options
1976 * if epfiles inherited ownership and permissons from ep0 ...
1979 static unsigned default_uid;
1980 static unsigned default_gid;
1981 static unsigned default_perm = S_IRUSR | S_IWUSR;
1983 module_param (default_uid, uint, 0644);
1984 module_param (default_gid, uint, 0644);
1985 module_param (default_perm, uint, 0644);
1988 static struct inode *
1989 gadgetfs_make_inode (struct super_block *sb,
1990 void *data, const struct file_operations *fops,
1993 struct inode *inode = new_inode (sb);
1996 inode->i_ino = get_next_ino();
1997 inode->i_mode = mode;
1998 inode->i_uid = default_uid;
1999 inode->i_gid = default_gid;
2000 inode->i_atime = inode->i_mtime = inode->i_ctime
2002 inode->i_private = data;
2003 inode->i_fop = fops;
2008 /* creates in fs root directory, so non-renamable and non-linkable.
2009 * so inode and dentry are paired, until device reconfig.
2011 static struct inode *
2012 gadgetfs_create_file (struct super_block *sb, char const *name,
2013 void *data, const struct file_operations *fops,
2014 struct dentry **dentry_p)
2016 struct dentry *dentry;
2017 struct inode *inode;
2019 dentry = d_alloc_name(sb->s_root, name);
2023 inode = gadgetfs_make_inode (sb, data, fops,
2024 S_IFREG | (default_perm & S_IRWXUGO));
2029 d_add (dentry, inode);
2034 static const struct super_operations gadget_fs_operations = {
2035 .statfs = simple_statfs,
2036 .drop_inode = generic_delete_inode,
2040 gadgetfs_fill_super (struct super_block *sb, void *opts, int silent)
2042 struct inode *inode;
2044 struct dev_data *dev;
2049 /* fake probe to determine $CHIP */
2050 (void) usb_gadget_probe_driver(&probe_driver, gadgetfs_probe);
2055 sb->s_blocksize = PAGE_CACHE_SIZE;
2056 sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
2057 sb->s_magic = GADGETFS_MAGIC;
2058 sb->s_op = &gadget_fs_operations;
2059 sb->s_time_gran = 1;
2062 inode = gadgetfs_make_inode (sb,
2063 NULL, &simple_dir_operations,
2064 S_IFDIR | S_IRUGO | S_IXUGO);
2067 inode->i_op = &simple_dir_inode_operations;
2068 if (!(d = d_alloc_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 if (!gadgetfs_create_file (sb, CHIP,
2081 dev, &dev_init_operations,
2085 /* other endpoint files are available after hardware setup,
2086 * from binding to a controller.
2101 /* "mount -t gadgetfs path /dev/gadget" ends up here */
2102 static struct dentry *
2103 gadgetfs_mount (struct file_system_type *t, int flags,
2104 const char *path, void *opts)
2106 return mount_single (t, flags, opts, gadgetfs_fill_super);
2110 gadgetfs_kill_sb (struct super_block *sb)
2112 kill_litter_super (sb);
2114 put_dev (the_device);
2119 /*----------------------------------------------------------------------*/
2121 static struct file_system_type gadgetfs_type = {
2122 .owner = THIS_MODULE,
2124 .mount = gadgetfs_mount,
2125 .kill_sb = gadgetfs_kill_sb,
2128 /*----------------------------------------------------------------------*/
2130 static int __init init (void)
2134 status = register_filesystem (&gadgetfs_type);
2136 pr_info ("%s: %s, version " DRIVER_VERSION "\n",
2137 shortname, driver_desc);
2142 static void __exit cleanup (void)
2144 pr_debug ("unregister %s\n", shortname);
2145 unregister_filesystem (&gadgetfs_type);
2147 module_exit (cleanup);