2 * inode.c -- user mode filesystem api for usb gadget controllers
4 * Copyright (C) 2003-2004 David Brownell
5 * Copyright (C) 2003 Agilent Technologies
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 2 of the License, or
10 * (at your option) any later version.
14 /* #define VERBOSE_DEBUG */
16 #include <linux/init.h>
17 #include <linux/module.h>
19 #include <linux/pagemap.h>
20 #include <linux/uts.h>
21 #include <linux/wait.h>
22 #include <linux/compiler.h>
23 #include <asm/uaccess.h>
24 #include <linux/sched.h>
25 #include <linux/slab.h>
26 #include <linux/poll.h>
27 #include <linux/delay.h>
28 #include <linux/device.h>
29 #include <linux/moduleparam.h>
31 #include <linux/usb/gadgetfs.h>
32 #include <linux/usb/gadget.h>
36 * The gadgetfs API maps each endpoint to a file descriptor so that you
37 * can use standard synchronous read/write calls for I/O. There's some
38 * O_NONBLOCK and O_ASYNC/FASYNC style i/o support. Example usermode
39 * drivers show how this works in practice. You can also use AIO to
40 * eliminate I/O gaps between requests, to help when streaming data.
42 * Key parts that must be USB-specific are protocols defining how the
43 * read/write operations relate to the hardware state machines. There
44 * are two types of files. One type is for the device, implementing ep0.
45 * The other type is for each IN or OUT endpoint. In both cases, the
46 * user mode driver must configure the hardware before using it.
48 * - First, dev_config() is called when /dev/gadget/$CHIP is configured
49 * (by writing configuration and device descriptors). Afterwards it
50 * may serve as a source of device events, used to handle all control
51 * requests other than basic enumeration.
53 * - Then, after a SET_CONFIGURATION control request, ep_config() is
54 * called when each /dev/gadget/ep* file is configured (by writing
55 * endpoint descriptors). Afterwards these files are used to write()
56 * IN data or to read() OUT data. To halt the endpoint, a "wrong
57 * direction" request is issued (like reading an IN endpoint).
59 * Unlike "usbfs" the only ioctl()s are for things that are rare, and maybe
60 * not possible on all hardware. For example, precise fault handling with
61 * respect to data left in endpoint fifos after aborted operations; or
62 * selective clearing of endpoint halts, to implement SET_INTERFACE.
65 #define DRIVER_DESC "USB Gadget filesystem"
66 #define DRIVER_VERSION "24 Aug 2004"
68 static const char driver_desc [] = DRIVER_DESC;
69 static const char shortname [] = "gadgetfs";
71 MODULE_DESCRIPTION (DRIVER_DESC);
72 MODULE_AUTHOR ("David Brownell");
73 MODULE_LICENSE ("GPL");
76 /*----------------------------------------------------------------------*/
78 #define GADGETFS_MAGIC 0xaee71ee7
79 #define DMA_ADDR_INVALID (~(dma_addr_t)0)
81 /* /dev/gadget/$CHIP represents ep0 and the whole device */
83 /* DISBLED is the initial state.
85 STATE_DEV_DISABLED = 0,
87 /* Only one open() of /dev/gadget/$CHIP; only one file tracks
88 * ep0/device i/o modes and binding to the controller. Driver
89 * must always write descriptors to initialize the device, then
90 * the device becomes UNCONNECTED until enumeration.
94 /* From then on, ep0 fd is in either of two basic modes:
95 * - (UN)CONNECTED: read usb_gadgetfs_event(s) from it
96 * - SETUP: read/write will transfer control data and succeed;
97 * or if "wrong direction", performs protocol stall
99 STATE_DEV_UNCONNECTED,
103 /* UNBOUND means the driver closed ep0, so the device won't be
104 * accessible again (DEV_DISABLED) until all fds are closed.
109 /* enough for the whole queue: most events invalidate others */
116 enum ep0_state state; /* P: lock */
117 struct usb_gadgetfs_event event [N_EVENT];
119 struct fasync_struct *fasync;
122 /* drivers reading ep0 MUST handle control requests (SETUP)
123 * reported that way; else the host will time out.
125 unsigned usermode_setup : 1,
131 unsigned setup_wLength;
133 /* the rest is basically write-once */
134 struct usb_config_descriptor *config, *hs_config;
135 struct usb_device_descriptor *dev;
136 struct usb_request *req;
137 struct usb_gadget *gadget;
138 struct list_head epfiles;
140 wait_queue_head_t wait;
141 struct super_block *sb;
142 struct dentry *dentry;
144 /* except this scratch i/o buffer for ep0 */
148 static inline void get_dev (struct dev_data *data)
150 atomic_inc (&data->count);
153 static void put_dev (struct dev_data *data)
155 if (likely (!atomic_dec_and_test (&data->count)))
157 /* needs no more cleanup */
158 BUG_ON (waitqueue_active (&data->wait));
162 static struct dev_data *dev_new (void)
164 struct dev_data *dev;
166 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
169 dev->state = STATE_DEV_DISABLED;
170 atomic_set (&dev->count, 1);
171 spin_lock_init (&dev->lock);
172 INIT_LIST_HEAD (&dev->epfiles);
173 init_waitqueue_head (&dev->wait);
177 /*----------------------------------------------------------------------*/
179 /* other /dev/gadget/$ENDPOINT files represent endpoints */
181 STATE_EP_DISABLED = 0,
191 struct dev_data *dev;
192 /* must hold dev->lock before accessing ep or req */
194 struct usb_request *req;
197 struct usb_endpoint_descriptor desc, hs_desc;
198 struct list_head epfiles;
199 wait_queue_head_t wait;
200 struct dentry *dentry;
204 static inline void get_ep (struct ep_data *data)
206 atomic_inc (&data->count);
209 static void put_ep (struct ep_data *data)
211 if (likely (!atomic_dec_and_test (&data->count)))
214 /* needs no more cleanup */
215 BUG_ON (!list_empty (&data->epfiles));
216 BUG_ON (waitqueue_active (&data->wait));
220 /*----------------------------------------------------------------------*/
222 /* most "how to use the hardware" policy choices are in userspace:
223 * mapping endpoint roles (which the driver needs) to the capabilities
224 * which the usb controller has. most of those capabilities are exposed
225 * implicitly, starting with the driver name and then endpoint names.
228 static const char *CHIP;
230 /*----------------------------------------------------------------------*/
232 /* NOTE: don't use dev_printk calls before binding to the gadget
233 * at the end of ep0 configuration, or after unbind.
236 /* too wordy: dev_printk(level , &(d)->gadget->dev , fmt , ## args) */
237 #define xprintk(d,level,fmt,args...) \
238 printk(level "%s: " fmt , shortname , ## args)
241 #define DBG(dev,fmt,args...) \
242 xprintk(dev , KERN_DEBUG , fmt , ## args)
244 #define DBG(dev,fmt,args...) \
251 #define VDEBUG(dev,fmt,args...) \
255 #define ERROR(dev,fmt,args...) \
256 xprintk(dev , KERN_ERR , fmt , ## args)
257 #define INFO(dev,fmt,args...) \
258 xprintk(dev , KERN_INFO , fmt , ## args)
261 /*----------------------------------------------------------------------*/
263 /* SYNCHRONOUS ENDPOINT OPERATIONS (bulk/intr/iso)
265 * After opening, configure non-control endpoints. Then use normal
266 * stream read() and write() requests; and maybe ioctl() to get more
267 * precise FIFO status when recovering from cancellation.
270 static void epio_complete (struct usb_ep *ep, struct usb_request *req)
272 struct ep_data *epdata = ep->driver_data;
277 epdata->status = req->status;
279 epdata->status = req->actual;
280 complete ((struct completion *)req->context);
283 /* tasklock endpoint, returning when it's connected.
284 * still need dev->lock to use epdata->ep.
287 get_ready_ep (unsigned f_flags, struct ep_data *epdata)
291 if (f_flags & O_NONBLOCK) {
292 if (!mutex_trylock(&epdata->lock))
294 if (epdata->state != STATE_EP_ENABLED) {
295 mutex_unlock(&epdata->lock);
303 val = mutex_lock_interruptible(&epdata->lock);
307 switch (epdata->state) {
308 case STATE_EP_ENABLED:
310 // case STATE_EP_DISABLED: /* "can't happen" */
311 // case STATE_EP_READY: /* "can't happen" */
312 default: /* error! */
313 pr_debug ("%s: ep %p not available, state %d\n",
314 shortname, epdata, epdata->state);
316 case STATE_EP_UNBOUND: /* clean disconnect */
318 mutex_unlock(&epdata->lock);
324 ep_io (struct ep_data *epdata, void *buf, unsigned len)
326 DECLARE_COMPLETION_ONSTACK (done);
329 spin_lock_irq (&epdata->dev->lock);
330 if (likely (epdata->ep != NULL)) {
331 struct usb_request *req = epdata->req;
333 req->context = &done;
334 req->complete = epio_complete;
337 value = usb_ep_queue (epdata->ep, req, GFP_ATOMIC);
340 spin_unlock_irq (&epdata->dev->lock);
342 if (likely (value == 0)) {
343 value = wait_event_interruptible (done.wait, done.done);
345 spin_lock_irq (&epdata->dev->lock);
346 if (likely (epdata->ep != NULL)) {
347 DBG (epdata->dev, "%s i/o interrupted\n",
349 usb_ep_dequeue (epdata->ep, epdata->req);
350 spin_unlock_irq (&epdata->dev->lock);
352 wait_event (done.wait, done.done);
353 if (epdata->status == -ECONNRESET)
354 epdata->status = -EINTR;
356 spin_unlock_irq (&epdata->dev->lock);
358 DBG (epdata->dev, "endpoint gone\n");
359 epdata->status = -ENODEV;
362 return epdata->status;
368 /* handle a synchronous OUT bulk/intr/iso transfer */
370 ep_read (struct file *fd, char __user *buf, size_t len, loff_t *ptr)
372 struct ep_data *data = fd->private_data;
376 if ((value = get_ready_ep (fd->f_flags, data)) < 0)
379 /* halt any endpoint by doing a "wrong direction" i/o call */
380 if (usb_endpoint_dir_in(&data->desc)) {
381 if (usb_endpoint_xfer_isoc(&data->desc)) {
382 mutex_unlock(&data->lock);
385 DBG (data->dev, "%s halt\n", data->name);
386 spin_lock_irq (&data->dev->lock);
387 if (likely (data->ep != NULL))
388 usb_ep_set_halt (data->ep);
389 spin_unlock_irq (&data->dev->lock);
390 mutex_unlock(&data->lock);
394 /* FIXME readahead for O_NONBLOCK and poll(); careful with ZLPs */
397 kbuf = kmalloc (len, GFP_KERNEL);
398 if (unlikely (!kbuf))
401 value = ep_io (data, kbuf, len);
402 VDEBUG (data->dev, "%s read %zu OUT, status %d\n",
403 data->name, len, (int) value);
404 if (value >= 0 && copy_to_user (buf, kbuf, value))
408 mutex_unlock(&data->lock);
413 /* handle a synchronous IN bulk/intr/iso transfer */
415 ep_write (struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
417 struct ep_data *data = fd->private_data;
421 if ((value = get_ready_ep (fd->f_flags, data)) < 0)
424 /* halt any endpoint by doing a "wrong direction" i/o call */
425 if (!usb_endpoint_dir_in(&data->desc)) {
426 if (usb_endpoint_xfer_isoc(&data->desc)) {
427 mutex_unlock(&data->lock);
430 DBG (data->dev, "%s halt\n", data->name);
431 spin_lock_irq (&data->dev->lock);
432 if (likely (data->ep != NULL))
433 usb_ep_set_halt (data->ep);
434 spin_unlock_irq (&data->dev->lock);
435 mutex_unlock(&data->lock);
439 /* FIXME writebehind for O_NONBLOCK and poll(), qlen = 1 */
442 kbuf = kmalloc (len, GFP_KERNEL);
445 if (copy_from_user (kbuf, buf, len)) {
450 value = ep_io (data, kbuf, len);
451 VDEBUG (data->dev, "%s write %zu IN, status %d\n",
452 data->name, len, (int) value);
454 mutex_unlock(&data->lock);
460 ep_release (struct inode *inode, struct file *fd)
462 struct ep_data *data = fd->private_data;
465 value = mutex_lock_interruptible(&data->lock);
469 /* clean up if this can be reopened */
470 if (data->state != STATE_EP_UNBOUND) {
471 data->state = STATE_EP_DISABLED;
472 data->desc.bDescriptorType = 0;
473 data->hs_desc.bDescriptorType = 0;
474 usb_ep_disable(data->ep);
476 mutex_unlock(&data->lock);
481 static long ep_ioctl(struct file *fd, unsigned code, unsigned long value)
483 struct ep_data *data = fd->private_data;
486 if ((status = get_ready_ep (fd->f_flags, data)) < 0)
489 spin_lock_irq (&data->dev->lock);
490 if (likely (data->ep != NULL)) {
492 case GADGETFS_FIFO_STATUS:
493 status = usb_ep_fifo_status (data->ep);
495 case GADGETFS_FIFO_FLUSH:
496 usb_ep_fifo_flush (data->ep);
498 case GADGETFS_CLEAR_HALT:
499 status = usb_ep_clear_halt (data->ep);
506 spin_unlock_irq (&data->dev->lock);
507 mutex_unlock(&data->lock);
511 /*----------------------------------------------------------------------*/
513 /* ASYNCHRONOUS ENDPOINT I/O OPERATIONS (bulk/intr/iso) */
516 struct usb_request *req;
517 struct ep_data *epdata;
519 const struct iovec *iv;
520 unsigned long nr_segs;
524 static int ep_aio_cancel(struct kiocb *iocb, struct io_event *e)
526 struct kiocb_priv *priv = iocb->private;
527 struct ep_data *epdata;
531 epdata = priv->epdata;
532 // spin_lock(&epdata->dev->lock);
533 kiocbSetCancelled(iocb);
534 if (likely(epdata && epdata->ep && priv->req))
535 value = usb_ep_dequeue (epdata->ep, priv->req);
538 // spin_unlock(&epdata->dev->lock);
545 static ssize_t ep_aio_read_retry(struct kiocb *iocb)
547 struct kiocb_priv *priv = iocb->private;
552 /* we "retry" to get the right mm context for this: */
554 /* copy stuff into user buffers */
555 total = priv->actual;
558 for (i=0; i < priv->nr_segs; i++) {
559 ssize_t this = min((ssize_t)(priv->iv[i].iov_len), total);
561 if (copy_to_user(priv->iv[i].iov_base, to_copy, this)) {
579 static void ep_aio_complete(struct usb_ep *ep, struct usb_request *req)
581 struct kiocb *iocb = req->context;
582 struct kiocb_priv *priv = iocb->private;
583 struct ep_data *epdata = priv->epdata;
585 /* lock against disconnect (and ideally, cancel) */
586 spin_lock(&epdata->dev->lock);
590 /* if this was a write or a read returning no data then we
591 * don't need to copy anything to userspace, so we can
592 * complete the aio request immediately.
594 if (priv->iv == NULL || unlikely(req->actual == 0)) {
598 iocb->private = NULL;
599 /* aio_complete() reports bytes-transferred _and_ faults */
600 aio_complete(iocb, req->actual ? req->actual : req->status,
603 /* retry() won't report both; so we hide some faults */
604 if (unlikely(0 != req->status))
605 DBG(epdata->dev, "%s fault %d len %d\n",
606 ep->name, req->status, req->actual);
608 priv->buf = req->buf;
609 priv->actual = req->actual;
613 usb_ep_free_request(ep, req);
614 spin_unlock(&epdata->dev->lock);
623 struct ep_data *epdata,
624 const struct iovec *iv,
625 unsigned long nr_segs
628 struct kiocb_priv *priv;
629 struct usb_request *req;
632 priv = kzalloc(sizeof *priv, GFP_KERNEL);
639 iocb->private = priv;
641 priv->iv = kmemdup(iv, nr_segs * sizeof(struct iovec),
649 priv->nr_segs = nr_segs;
651 value = get_ready_ep(iocb->ki_filp->f_flags, epdata);
652 if (unlikely(value < 0)) {
658 iocb->ki_cancel = ep_aio_cancel;
660 priv->epdata = epdata;
663 /* each kiocb is coupled to one usb_request, but we can't
664 * allocate or submit those if the host disconnected.
666 spin_lock_irq(&epdata->dev->lock);
667 if (likely(epdata->ep)) {
668 req = usb_ep_alloc_request(epdata->ep, GFP_ATOMIC);
673 req->complete = ep_aio_complete;
675 value = usb_ep_queue(epdata->ep, req, GFP_ATOMIC);
676 if (unlikely(0 != value))
677 usb_ep_free_request(epdata->ep, req);
682 spin_unlock_irq(&epdata->dev->lock);
684 mutex_unlock(&epdata->lock);
686 if (unlikely(value)) {
691 value = (iv ? -EIOCBRETRY : -EIOCBQUEUED);
696 ep_aio_read(struct kiocb *iocb, const struct iovec *iov,
697 unsigned long nr_segs, loff_t o)
699 struct ep_data *epdata = iocb->ki_filp->private_data;
702 if (unlikely(usb_endpoint_dir_in(&epdata->desc)))
705 buf = kmalloc(iocb->ki_left, GFP_KERNEL);
709 iocb->ki_retry = ep_aio_read_retry;
710 return ep_aio_rwtail(iocb, buf, iocb->ki_left, epdata, iov, nr_segs);
714 ep_aio_write(struct kiocb *iocb, const struct iovec *iov,
715 unsigned long nr_segs, loff_t o)
717 struct ep_data *epdata = iocb->ki_filp->private_data;
722 if (unlikely(!usb_endpoint_dir_in(&epdata->desc)))
725 buf = kmalloc(iocb->ki_left, GFP_KERNEL);
729 for (i=0; i < nr_segs; i++) {
730 if (unlikely(copy_from_user(&buf[len], iov[i].iov_base,
731 iov[i].iov_len) != 0)) {
735 len += iov[i].iov_len;
737 return ep_aio_rwtail(iocb, buf, len, epdata, NULL, 0);
740 /*----------------------------------------------------------------------*/
742 /* used after endpoint configuration */
743 static const struct file_operations ep_io_operations = {
744 .owner = THIS_MODULE,
749 .unlocked_ioctl = ep_ioctl,
750 .release = ep_release,
752 .aio_read = ep_aio_read,
753 .aio_write = ep_aio_write,
756 /* ENDPOINT INITIALIZATION
758 * fd = open ("/dev/gadget/$ENDPOINT", O_RDWR)
759 * status = write (fd, descriptors, sizeof descriptors)
761 * That write establishes the endpoint configuration, configuring
762 * the controller to process bulk, interrupt, or isochronous transfers
763 * at the right maxpacket size, and so on.
765 * The descriptors are message type 1, identified by a host order u32
766 * at the beginning of what's written. Descriptor order is: full/low
767 * speed descriptor, then optional high speed descriptor.
770 ep_config (struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
772 struct ep_data *data = fd->private_data;
775 int value, length = len;
777 value = mutex_lock_interruptible(&data->lock);
781 if (data->state != STATE_EP_READY) {
787 if (len < USB_DT_ENDPOINT_SIZE + 4)
790 /* we might need to change message format someday */
791 if (copy_from_user (&tag, buf, 4)) {
795 DBG(data->dev, "config %s, bad tag %d\n", data->name, tag);
801 /* NOTE: audio endpoint extensions not accepted here;
802 * just don't include the extra bytes.
805 /* full/low speed descriptor, then high speed */
806 if (copy_from_user (&data->desc, buf, USB_DT_ENDPOINT_SIZE)) {
809 if (data->desc.bLength != USB_DT_ENDPOINT_SIZE
810 || data->desc.bDescriptorType != USB_DT_ENDPOINT)
812 if (len != USB_DT_ENDPOINT_SIZE) {
813 if (len != 2 * USB_DT_ENDPOINT_SIZE)
815 if (copy_from_user (&data->hs_desc, buf + USB_DT_ENDPOINT_SIZE,
816 USB_DT_ENDPOINT_SIZE)) {
819 if (data->hs_desc.bLength != USB_DT_ENDPOINT_SIZE
820 || data->hs_desc.bDescriptorType
821 != USB_DT_ENDPOINT) {
822 DBG(data->dev, "config %s, bad hs length or type\n",
828 spin_lock_irq (&data->dev->lock);
829 if (data->dev->state == STATE_DEV_UNBOUND) {
832 } else if ((ep = data->ep) == NULL) {
836 switch (data->dev->gadget->speed) {
839 ep->desc = &data->desc;
840 value = usb_ep_enable(ep);
842 data->state = STATE_EP_ENABLED;
844 #ifdef CONFIG_USB_GADGET_DUALSPEED
846 /* fails if caller didn't provide that descriptor... */
847 ep->desc = &data->hs_desc;
848 value = usb_ep_enable(ep);
850 data->state = STATE_EP_ENABLED;
854 DBG(data->dev, "unconnected, %s init abandoned\n",
859 fd->f_op = &ep_io_operations;
863 spin_unlock_irq (&data->dev->lock);
866 data->desc.bDescriptorType = 0;
867 data->hs_desc.bDescriptorType = 0;
869 mutex_unlock(&data->lock);
880 ep_open (struct inode *inode, struct file *fd)
882 struct ep_data *data = inode->i_private;
885 if (mutex_lock_interruptible(&data->lock) != 0)
887 spin_lock_irq (&data->dev->lock);
888 if (data->dev->state == STATE_DEV_UNBOUND)
890 else if (data->state == STATE_EP_DISABLED) {
892 data->state = STATE_EP_READY;
894 fd->private_data = data;
895 VDEBUG (data->dev, "%s ready\n", data->name);
897 DBG (data->dev, "%s state %d\n",
898 data->name, data->state);
899 spin_unlock_irq (&data->dev->lock);
900 mutex_unlock(&data->lock);
904 /* used before endpoint configuration */
905 static const struct file_operations ep_config_operations = {
906 .owner = THIS_MODULE,
911 .release = ep_release,
914 /*----------------------------------------------------------------------*/
916 /* EP0 IMPLEMENTATION can be partly in userspace.
918 * Drivers that use this facility receive various events, including
919 * control requests the kernel doesn't handle. Drivers that don't
920 * use this facility may be too simple-minded for real applications.
923 static inline void ep0_readable (struct dev_data *dev)
925 wake_up (&dev->wait);
926 kill_fasync (&dev->fasync, SIGIO, POLL_IN);
929 static void clean_req (struct usb_ep *ep, struct usb_request *req)
931 struct dev_data *dev = ep->driver_data;
933 if (req->buf != dev->rbuf) {
935 req->buf = dev->rbuf;
936 req->dma = DMA_ADDR_INVALID;
938 req->complete = epio_complete;
939 dev->setup_out_ready = 0;
942 static void ep0_complete (struct usb_ep *ep, struct usb_request *req)
944 struct dev_data *dev = ep->driver_data;
948 /* for control OUT, data must still get to userspace */
949 spin_lock_irqsave(&dev->lock, flags);
950 if (!dev->setup_in) {
951 dev->setup_out_error = (req->status != 0);
952 if (!dev->setup_out_error)
954 dev->setup_out_ready = 1;
958 /* clean up as appropriate */
959 if (free && req->buf != &dev->rbuf)
961 req->complete = epio_complete;
962 spin_unlock_irqrestore(&dev->lock, flags);
965 static int setup_req (struct usb_ep *ep, struct usb_request *req, u16 len)
967 struct dev_data *dev = ep->driver_data;
969 if (dev->setup_out_ready) {
970 DBG (dev, "ep0 request busy!\n");
973 if (len > sizeof (dev->rbuf))
974 req->buf = kmalloc(len, GFP_ATOMIC);
975 if (req->buf == NULL) {
976 req->buf = dev->rbuf;
979 req->complete = ep0_complete;
986 ep0_read (struct file *fd, char __user *buf, size_t len, loff_t *ptr)
988 struct dev_data *dev = fd->private_data;
990 enum ep0_state state;
992 spin_lock_irq (&dev->lock);
994 /* report fd mode change before acting on it */
995 if (dev->setup_abort) {
996 dev->setup_abort = 0;
1001 /* control DATA stage */
1002 if ((state = dev->state) == STATE_DEV_SETUP) {
1004 if (dev->setup_in) { /* stall IN */
1005 VDEBUG(dev, "ep0in stall\n");
1006 (void) usb_ep_set_halt (dev->gadget->ep0);
1008 dev->state = STATE_DEV_CONNECTED;
1010 } else if (len == 0) { /* ack SET_CONFIGURATION etc */
1011 struct usb_ep *ep = dev->gadget->ep0;
1012 struct usb_request *req = dev->req;
1014 if ((retval = setup_req (ep, req, 0)) == 0) {
1016 spin_unlock_irq (&dev->lock);
1017 retval = usb_ep_queue (ep, req, GFP_KERNEL);
1018 spin_lock_irq (&dev->lock);
1021 dev->state = STATE_DEV_CONNECTED;
1023 /* assume that was SET_CONFIGURATION */
1024 if (dev->current_config) {
1027 if (gadget_is_dualspeed(dev->gadget)
1028 && (dev->gadget->speed
1030 power = dev->hs_config->bMaxPower;
1032 power = dev->config->bMaxPower;
1033 usb_gadget_vbus_draw(dev->gadget, 2 * power);
1036 } else { /* collect OUT data */
1037 if ((fd->f_flags & O_NONBLOCK) != 0
1038 && !dev->setup_out_ready) {
1042 spin_unlock_irq (&dev->lock);
1043 retval = wait_event_interruptible (dev->wait,
1044 dev->setup_out_ready != 0);
1046 /* FIXME state could change from under us */
1047 spin_lock_irq (&dev->lock);
1051 if (dev->state != STATE_DEV_SETUP) {
1052 retval = -ECANCELED;
1055 dev->state = STATE_DEV_CONNECTED;
1057 if (dev->setup_out_error)
1060 len = min (len, (size_t)dev->req->actual);
1062 spin_unlock_irq(&dev->lock);
1063 if (copy_to_user (buf, dev->req->buf, len))
1067 spin_lock_irq(&dev->lock);
1069 clean_req (dev->gadget->ep0, dev->req);
1070 /* NOTE userspace can't yet choose to stall */
1076 /* else normal: return event data */
1077 if (len < sizeof dev->event [0]) {
1081 len -= len % sizeof (struct usb_gadgetfs_event);
1082 dev->usermode_setup = 1;
1085 /* return queued events right away */
1086 if (dev->ev_next != 0) {
1089 n = len / sizeof (struct usb_gadgetfs_event);
1090 if (dev->ev_next < n)
1093 /* ep0 i/o has special semantics during STATE_DEV_SETUP */
1094 for (i = 0; i < n; i++) {
1095 if (dev->event [i].type == GADGETFS_SETUP) {
1096 dev->state = STATE_DEV_SETUP;
1101 spin_unlock_irq (&dev->lock);
1102 len = n * sizeof (struct usb_gadgetfs_event);
1103 if (copy_to_user (buf, &dev->event, len))
1108 /* NOTE this doesn't guard against broken drivers;
1109 * concurrent ep0 readers may lose events.
1111 spin_lock_irq (&dev->lock);
1112 if (dev->ev_next > n) {
1113 memmove(&dev->event[0], &dev->event[n],
1114 sizeof (struct usb_gadgetfs_event)
1115 * (dev->ev_next - n));
1118 spin_unlock_irq (&dev->lock);
1122 if (fd->f_flags & O_NONBLOCK) {
1129 DBG (dev, "fail %s, state %d\n", __func__, state);
1132 case STATE_DEV_UNCONNECTED:
1133 case STATE_DEV_CONNECTED:
1134 spin_unlock_irq (&dev->lock);
1135 DBG (dev, "%s wait\n", __func__);
1137 /* wait for events */
1138 retval = wait_event_interruptible (dev->wait,
1142 spin_lock_irq (&dev->lock);
1147 spin_unlock_irq (&dev->lock);
1151 static struct usb_gadgetfs_event *
1152 next_event (struct dev_data *dev, enum usb_gadgetfs_event_type type)
1154 struct usb_gadgetfs_event *event;
1158 /* these events purge the queue */
1159 case GADGETFS_DISCONNECT:
1160 if (dev->state == STATE_DEV_SETUP)
1161 dev->setup_abort = 1;
1163 case GADGETFS_CONNECT:
1166 case GADGETFS_SETUP: /* previous request timed out */
1167 case GADGETFS_SUSPEND: /* same effect */
1168 /* these events can't be repeated */
1169 for (i = 0; i != dev->ev_next; i++) {
1170 if (dev->event [i].type != type)
1172 DBG(dev, "discard old event[%d] %d\n", i, type);
1174 if (i == dev->ev_next)
1176 /* indices start at zero, for simplicity */
1177 memmove (&dev->event [i], &dev->event [i + 1],
1178 sizeof (struct usb_gadgetfs_event)
1179 * (dev->ev_next - i));
1185 VDEBUG(dev, "event[%d] = %d\n", dev->ev_next, type);
1186 event = &dev->event [dev->ev_next++];
1187 BUG_ON (dev->ev_next > N_EVENT);
1188 memset (event, 0, sizeof *event);
1194 ep0_write (struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
1196 struct dev_data *dev = fd->private_data;
1197 ssize_t retval = -ESRCH;
1199 spin_lock_irq (&dev->lock);
1201 /* report fd mode change before acting on it */
1202 if (dev->setup_abort) {
1203 dev->setup_abort = 0;
1206 /* data and/or status stage for control request */
1207 } else if (dev->state == STATE_DEV_SETUP) {
1209 len = min_t(size_t, len, dev->setup_wLength);
1210 if (dev->setup_in) {
1211 retval = setup_req (dev->gadget->ep0, dev->req, len);
1213 dev->state = STATE_DEV_CONNECTED;
1215 spin_unlock_irq (&dev->lock);
1216 if (copy_from_user (dev->req->buf, buf, len))
1219 if (len < dev->setup_wLength)
1221 retval = usb_ep_queue (
1222 dev->gadget->ep0, dev->req,
1225 spin_lock_irq(&dev->lock);
1228 clean_req (dev->gadget->ep0, dev->req);
1231 spin_unlock_irq(&dev->lock);
1236 /* can stall some OUT transfers */
1237 } else if (dev->setup_can_stall) {
1238 VDEBUG(dev, "ep0out stall\n");
1239 (void) usb_ep_set_halt (dev->gadget->ep0);
1241 dev->state = STATE_DEV_CONNECTED;
1243 DBG(dev, "bogus ep0out stall!\n");
1246 DBG (dev, "fail %s, state %d\n", __func__, dev->state);
1248 spin_unlock_irq (&dev->lock);
1253 ep0_fasync (int f, struct file *fd, int on)
1255 struct dev_data *dev = fd->private_data;
1256 // caller must F_SETOWN before signal delivery happens
1257 VDEBUG (dev, "%s %s\n", __func__, on ? "on" : "off");
1258 return fasync_helper (f, fd, on, &dev->fasync);
1261 static struct usb_gadget_driver gadgetfs_driver;
1264 dev_release (struct inode *inode, struct file *fd)
1266 struct dev_data *dev = fd->private_data;
1268 /* closing ep0 === shutdown all */
1270 usb_gadget_unregister_driver (&gadgetfs_driver);
1272 /* at this point "good" hardware has disconnected the
1273 * device from USB; the host won't see it any more.
1274 * alternatively, all host requests will time out.
1281 /* other endpoints were all decoupled from this device */
1282 spin_lock_irq(&dev->lock);
1283 dev->state = STATE_DEV_DISABLED;
1284 spin_unlock_irq(&dev->lock);
1289 ep0_poll (struct file *fd, poll_table *wait)
1291 struct dev_data *dev = fd->private_data;
1294 poll_wait(fd, &dev->wait, wait);
1296 spin_lock_irq (&dev->lock);
1298 /* report fd mode change before acting on it */
1299 if (dev->setup_abort) {
1300 dev->setup_abort = 0;
1305 if (dev->state == STATE_DEV_SETUP) {
1306 if (dev->setup_in || dev->setup_can_stall)
1309 if (dev->ev_next != 0)
1313 spin_unlock_irq(&dev->lock);
1317 static long dev_ioctl (struct file *fd, unsigned code, unsigned long value)
1319 struct dev_data *dev = fd->private_data;
1320 struct usb_gadget *gadget = dev->gadget;
1323 spin_lock_irq(&dev->lock);
1324 if (dev->state == STATE_DEV_OPENED ||
1325 dev->state == STATE_DEV_UNBOUND) {
1326 /* Not bound to a UDC */
1327 } else if (gadget->ops->ioctl) {
1329 spin_unlock_irq(&dev->lock);
1331 ret = gadget->ops->ioctl (gadget, code, value);
1333 spin_lock_irq(&dev->lock);
1336 spin_unlock_irq(&dev->lock);
1341 /* used after device configuration */
1342 static const struct file_operations ep0_io_operations = {
1343 .owner = THIS_MODULE,
1344 .llseek = no_llseek,
1348 .fasync = ep0_fasync,
1350 .unlocked_ioctl = dev_ioctl,
1351 .release = dev_release,
1354 /*----------------------------------------------------------------------*/
1356 /* The in-kernel gadget driver handles most ep0 issues, in particular
1357 * enumerating the single configuration (as provided from user space).
1359 * Unrecognized ep0 requests may be handled in user space.
1362 #ifdef CONFIG_USB_GADGET_DUALSPEED
1363 static void make_qualifier (struct dev_data *dev)
1365 struct usb_qualifier_descriptor qual;
1366 struct usb_device_descriptor *desc;
1368 qual.bLength = sizeof qual;
1369 qual.bDescriptorType = USB_DT_DEVICE_QUALIFIER;
1370 qual.bcdUSB = cpu_to_le16 (0x0200);
1373 qual.bDeviceClass = desc->bDeviceClass;
1374 qual.bDeviceSubClass = desc->bDeviceSubClass;
1375 qual.bDeviceProtocol = desc->bDeviceProtocol;
1377 /* assumes ep0 uses the same value for both speeds ... */
1378 qual.bMaxPacketSize0 = dev->gadget->ep0->maxpacket;
1380 qual.bNumConfigurations = 1;
1383 memcpy (dev->rbuf, &qual, sizeof qual);
1388 config_buf (struct dev_data *dev, u8 type, unsigned index)
1393 /* only one configuration */
1397 if (gadget_is_dualspeed(dev->gadget)) {
1398 hs = (dev->gadget->speed == USB_SPEED_HIGH);
1399 if (type == USB_DT_OTHER_SPEED_CONFIG)
1403 dev->req->buf = dev->hs_config;
1404 len = le16_to_cpu(dev->hs_config->wTotalLength);
1406 dev->req->buf = dev->config;
1407 len = le16_to_cpu(dev->config->wTotalLength);
1409 ((u8 *)dev->req->buf) [1] = type;
1414 gadgetfs_setup (struct usb_gadget *gadget, const struct usb_ctrlrequest *ctrl)
1416 struct dev_data *dev = get_gadget_data (gadget);
1417 struct usb_request *req = dev->req;
1418 int value = -EOPNOTSUPP;
1419 struct usb_gadgetfs_event *event;
1420 u16 w_value = le16_to_cpu(ctrl->wValue);
1421 u16 w_length = le16_to_cpu(ctrl->wLength);
1423 spin_lock (&dev->lock);
1424 dev->setup_abort = 0;
1425 if (dev->state == STATE_DEV_UNCONNECTED) {
1426 if (gadget_is_dualspeed(gadget)
1427 && gadget->speed == USB_SPEED_HIGH
1428 && dev->hs_config == NULL) {
1429 spin_unlock(&dev->lock);
1430 ERROR (dev, "no high speed config??\n");
1434 dev->state = STATE_DEV_CONNECTED;
1436 INFO (dev, "connected\n");
1437 event = next_event (dev, GADGETFS_CONNECT);
1438 event->u.speed = gadget->speed;
1441 /* host may have given up waiting for response. we can miss control
1442 * requests handled lower down (device/endpoint status and features);
1443 * then ep0_{read,write} will report the wrong status. controller
1444 * driver will have aborted pending i/o.
1446 } else if (dev->state == STATE_DEV_SETUP)
1447 dev->setup_abort = 1;
1449 req->buf = dev->rbuf;
1450 req->dma = DMA_ADDR_INVALID;
1451 req->context = NULL;
1452 value = -EOPNOTSUPP;
1453 switch (ctrl->bRequest) {
1455 case USB_REQ_GET_DESCRIPTOR:
1456 if (ctrl->bRequestType != USB_DIR_IN)
1458 switch (w_value >> 8) {
1461 value = min (w_length, (u16) sizeof *dev->dev);
1462 dev->dev->bMaxPacketSize0 = dev->gadget->ep0->maxpacket;
1463 req->buf = dev->dev;
1465 #ifdef CONFIG_USB_GADGET_DUALSPEED
1466 case USB_DT_DEVICE_QUALIFIER:
1467 if (!dev->hs_config)
1469 value = min (w_length, (u16)
1470 sizeof (struct usb_qualifier_descriptor));
1471 make_qualifier (dev);
1473 case USB_DT_OTHER_SPEED_CONFIG:
1477 value = config_buf (dev,
1481 value = min (w_length, (u16) value);
1486 default: // all others are errors
1491 /* currently one config, two speeds */
1492 case USB_REQ_SET_CONFIGURATION:
1493 if (ctrl->bRequestType != 0)
1495 if (0 == (u8) w_value) {
1497 dev->current_config = 0;
1498 usb_gadget_vbus_draw(gadget, 8 /* mA */ );
1499 // user mode expected to disable endpoints
1503 if (gadget_is_dualspeed(gadget)
1504 && gadget->speed == USB_SPEED_HIGH) {
1505 config = dev->hs_config->bConfigurationValue;
1506 power = dev->hs_config->bMaxPower;
1508 config = dev->config->bConfigurationValue;
1509 power = dev->config->bMaxPower;
1512 if (config == (u8) w_value) {
1514 dev->current_config = config;
1515 usb_gadget_vbus_draw(gadget, 2 * power);
1519 /* report SET_CONFIGURATION like any other control request,
1520 * except that usermode may not stall this. the next
1521 * request mustn't be allowed start until this finishes:
1522 * endpoints and threads set up, etc.
1524 * NOTE: older PXA hardware (before PXA 255: without UDCCFR)
1525 * has bad/racey automagic that prevents synchronizing here.
1526 * even kernel mode drivers often miss them.
1529 INFO (dev, "configuration #%d\n", dev->current_config);
1530 if (dev->usermode_setup) {
1531 dev->setup_can_stall = 0;
1537 #ifndef CONFIG_USB_GADGET_PXA25X
1538 /* PXA automagically handles this request too */
1539 case USB_REQ_GET_CONFIGURATION:
1540 if (ctrl->bRequestType != 0x80)
1542 *(u8 *)req->buf = dev->current_config;
1543 value = min (w_length, (u16) 1);
1549 VDEBUG (dev, "%s req%02x.%02x v%04x i%04x l%d\n",
1550 dev->usermode_setup ? "delegate" : "fail",
1551 ctrl->bRequestType, ctrl->bRequest,
1552 w_value, le16_to_cpu(ctrl->wIndex), w_length);
1554 /* if there's an ep0 reader, don't stall */
1555 if (dev->usermode_setup) {
1556 dev->setup_can_stall = 1;
1558 dev->setup_in = (ctrl->bRequestType & USB_DIR_IN)
1560 dev->setup_wLength = w_length;
1561 dev->setup_out_ready = 0;
1562 dev->setup_out_error = 0;
1565 /* read DATA stage for OUT right away */
1566 if (unlikely (!dev->setup_in && w_length)) {
1567 value = setup_req (gadget->ep0, dev->req,
1573 spin_unlock (&dev->lock);
1574 value = usb_ep_queue (gadget->ep0, dev->req,
1576 spin_lock (&dev->lock);
1579 clean_req (gadget->ep0, dev->req);
1583 /* we can't currently stall these */
1584 dev->setup_can_stall = 0;
1587 /* state changes when reader collects event */
1588 event = next_event (dev, GADGETFS_SETUP);
1589 event->u.setup = *ctrl;
1591 spin_unlock (&dev->lock);
1596 /* proceed with data transfer and status phases? */
1597 if (value >= 0 && dev->state != STATE_DEV_SETUP) {
1598 req->length = value;
1599 req->zero = value < w_length;
1602 spin_unlock (&dev->lock);
1603 value = usb_ep_queue (gadget->ep0, req, GFP_KERNEL);
1604 spin_lock(&dev->lock);
1606 spin_unlock(&dev->lock);
1608 DBG (dev, "ep_queue --> %d\n", value);
1614 /* device stalls when value < 0 */
1615 spin_unlock (&dev->lock);
1619 static void destroy_ep_files (struct dev_data *dev)
1621 struct list_head *entry, *tmp;
1623 DBG (dev, "%s %d\n", __func__, dev->state);
1625 /* dev->state must prevent interference */
1627 spin_lock_irq (&dev->lock);
1628 list_for_each_safe (entry, tmp, &dev->epfiles) {
1630 struct inode *parent;
1631 struct dentry *dentry;
1633 /* break link to FS */
1634 ep = list_entry (entry, struct ep_data, epfiles);
1635 list_del_init (&ep->epfiles);
1636 spin_unlock_irq (&dev->lock);
1638 dentry = ep->dentry;
1640 parent = dentry->d_parent->d_inode;
1642 /* break link to controller */
1643 mutex_lock(&ep->lock);
1644 if (ep->state == STATE_EP_ENABLED)
1645 (void) usb_ep_disable (ep->ep);
1646 ep->state = STATE_EP_UNBOUND;
1647 usb_ep_free_request (ep->ep, ep->req);
1649 mutex_unlock(&ep->lock);
1651 wake_up (&ep->wait);
1654 /* break link to dcache */
1655 mutex_lock (&parent->i_mutex);
1658 mutex_unlock (&parent->i_mutex);
1660 /* fds may still be open */
1663 spin_unlock_irq (&dev->lock);
1667 static struct inode *
1668 gadgetfs_create_file (struct super_block *sb, char const *name,
1669 void *data, const struct file_operations *fops,
1670 struct dentry **dentry_p);
1672 static int activate_ep_files (struct dev_data *dev)
1675 struct ep_data *data;
1677 gadget_for_each_ep (ep, dev->gadget) {
1679 data = kzalloc(sizeof(*data), GFP_KERNEL);
1682 data->state = STATE_EP_DISABLED;
1683 mutex_init(&data->lock);
1684 init_waitqueue_head (&data->wait);
1686 strncpy (data->name, ep->name, sizeof (data->name) - 1);
1687 atomic_set (&data->count, 1);
1692 ep->driver_data = data;
1694 data->req = usb_ep_alloc_request (ep, GFP_KERNEL);
1698 data->inode = gadgetfs_create_file (dev->sb, data->name,
1699 data, &ep_config_operations,
1703 list_add_tail (&data->epfiles, &dev->epfiles);
1708 usb_ep_free_request (ep, data->req);
1713 DBG (dev, "%s enomem\n", __func__);
1714 destroy_ep_files (dev);
1719 gadgetfs_unbind (struct usb_gadget *gadget)
1721 struct dev_data *dev = get_gadget_data (gadget);
1723 DBG (dev, "%s\n", __func__);
1725 spin_lock_irq (&dev->lock);
1726 dev->state = STATE_DEV_UNBOUND;
1727 while (dev->udc_usage > 0) {
1728 spin_unlock_irq(&dev->lock);
1729 usleep_range(1000, 2000);
1730 spin_lock_irq(&dev->lock);
1732 spin_unlock_irq (&dev->lock);
1734 destroy_ep_files (dev);
1735 gadget->ep0->driver_data = NULL;
1736 set_gadget_data (gadget, NULL);
1738 /* we've already been disconnected ... no i/o is active */
1740 usb_ep_free_request (gadget->ep0, dev->req);
1741 DBG (dev, "%s done\n", __func__);
1745 static struct dev_data *the_device;
1748 gadgetfs_bind (struct usb_gadget *gadget)
1750 struct dev_data *dev = the_device;
1754 if (0 != strcmp (CHIP, gadget->name)) {
1755 pr_err("%s expected %s controller not %s\n",
1756 shortname, CHIP, gadget->name);
1760 set_gadget_data (gadget, dev);
1761 dev->gadget = gadget;
1762 gadget->ep0->driver_data = dev;
1764 /* preallocate control response and buffer */
1765 dev->req = usb_ep_alloc_request (gadget->ep0, GFP_KERNEL);
1768 dev->req->context = NULL;
1769 dev->req->complete = epio_complete;
1771 if (activate_ep_files (dev) < 0)
1774 INFO (dev, "bound to %s driver\n", gadget->name);
1775 spin_lock_irq(&dev->lock);
1776 dev->state = STATE_DEV_UNCONNECTED;
1777 spin_unlock_irq(&dev->lock);
1782 gadgetfs_unbind (gadget);
1787 gadgetfs_disconnect (struct usb_gadget *gadget)
1789 struct dev_data *dev = get_gadget_data (gadget);
1790 unsigned long flags;
1792 spin_lock_irqsave (&dev->lock, flags);
1793 if (dev->state == STATE_DEV_UNCONNECTED)
1795 dev->state = STATE_DEV_UNCONNECTED;
1797 INFO (dev, "disconnected\n");
1798 next_event (dev, GADGETFS_DISCONNECT);
1801 spin_unlock_irqrestore (&dev->lock, flags);
1805 gadgetfs_suspend (struct usb_gadget *gadget)
1807 struct dev_data *dev = get_gadget_data (gadget);
1808 unsigned long flags;
1810 INFO (dev, "suspended from state %d\n", dev->state);
1811 spin_lock_irqsave(&dev->lock, flags);
1812 switch (dev->state) {
1813 case STATE_DEV_SETUP: // VERY odd... host died??
1814 case STATE_DEV_CONNECTED:
1815 case STATE_DEV_UNCONNECTED:
1816 next_event (dev, GADGETFS_SUSPEND);
1822 spin_unlock_irqrestore(&dev->lock, flags);
1825 static struct usb_gadget_driver gadgetfs_driver = {
1826 #ifdef CONFIG_USB_GADGET_DUALSPEED
1827 .speed = USB_SPEED_HIGH,
1829 .speed = USB_SPEED_FULL,
1831 .function = (char *) driver_desc,
1832 .unbind = gadgetfs_unbind,
1833 .setup = gadgetfs_setup,
1834 .disconnect = gadgetfs_disconnect,
1835 .suspend = gadgetfs_suspend,
1838 .name = (char *) shortname,
1842 /*----------------------------------------------------------------------*/
1844 static void gadgetfs_nop(struct usb_gadget *arg) { }
1846 static int gadgetfs_probe (struct usb_gadget *gadget)
1848 CHIP = gadget->name;
1852 static struct usb_gadget_driver probe_driver = {
1853 .speed = USB_SPEED_HIGH,
1854 .unbind = gadgetfs_nop,
1855 .setup = (void *)gadgetfs_nop,
1856 .disconnect = gadgetfs_nop,
1863 /* DEVICE INITIALIZATION
1865 * fd = open ("/dev/gadget/$CHIP", O_RDWR)
1866 * status = write (fd, descriptors, sizeof descriptors)
1868 * That write establishes the device configuration, so the kernel can
1869 * bind to the controller ... guaranteeing it can handle enumeration
1870 * at all necessary speeds. Descriptor order is:
1872 * . message tag (u32, host order) ... for now, must be zero; it
1873 * would change to support features like multi-config devices
1874 * . full/low speed config ... all wTotalLength bytes (with interface,
1875 * class, altsetting, endpoint, and other descriptors)
1876 * . high speed config ... all descriptors, for high speed operation;
1877 * this one's optional except for high-speed hardware
1878 * . device descriptor
1880 * Endpoints are not yet enabled. Drivers must wait until device
1881 * configuration and interface altsetting changes create
1882 * the need to configure (or unconfigure) them.
1884 * After initialization, the device stays active for as long as that
1885 * $CHIP file is open. Events must then be read from that descriptor,
1886 * such as configuration notifications.
1889 static int is_valid_config(struct usb_config_descriptor *config,
1892 return config->bDescriptorType == USB_DT_CONFIG
1893 && config->bLength == USB_DT_CONFIG_SIZE
1894 && total >= USB_DT_CONFIG_SIZE
1895 && config->bConfigurationValue != 0
1896 && (config->bmAttributes & USB_CONFIG_ATT_ONE) != 0
1897 && (config->bmAttributes & USB_CONFIG_ATT_WAKEUP) == 0;
1898 /* FIXME if gadget->is_otg, _must_ include an otg descriptor */
1899 /* FIXME check lengths: walk to end */
1903 dev_config (struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
1905 struct dev_data *dev = fd->private_data;
1906 ssize_t value = len, length = len;
1911 if ((len < (USB_DT_CONFIG_SIZE + USB_DT_DEVICE_SIZE + 4)) ||
1912 (len > PAGE_SIZE * 4))
1915 /* we might need to change message format someday */
1916 if (copy_from_user (&tag, buf, 4))
1923 kbuf = memdup_user(buf, length);
1925 return PTR_ERR(kbuf);
1927 spin_lock_irq (&dev->lock);
1933 /* full or low speed config */
1934 dev->config = (void *) kbuf;
1935 total = le16_to_cpu(dev->config->wTotalLength);
1936 if (!is_valid_config(dev->config, total) ||
1937 total > length - USB_DT_DEVICE_SIZE)
1942 /* optional high speed config */
1943 if (kbuf [1] == USB_DT_CONFIG) {
1944 dev->hs_config = (void *) kbuf;
1945 total = le16_to_cpu(dev->hs_config->wTotalLength);
1946 if (!is_valid_config(dev->hs_config, total) ||
1947 total > length - USB_DT_DEVICE_SIZE)
1952 dev->hs_config = NULL;
1955 /* could support multiple configs, using another encoding! */
1957 /* device descriptor (tweaked for paranoia) */
1958 if (length != USB_DT_DEVICE_SIZE)
1960 dev->dev = (void *)kbuf;
1961 if (dev->dev->bLength != USB_DT_DEVICE_SIZE
1962 || dev->dev->bDescriptorType != USB_DT_DEVICE
1963 || dev->dev->bNumConfigurations != 1)
1965 dev->dev->bNumConfigurations = 1;
1966 dev->dev->bcdUSB = cpu_to_le16 (0x0200);
1968 /* triggers gadgetfs_bind(); then we can enumerate. */
1969 spin_unlock_irq (&dev->lock);
1970 value = usb_gadget_probe_driver(&gadgetfs_driver, gadgetfs_bind);
1975 /* at this point "good" hardware has for the first time
1976 * let the USB the host see us. alternatively, if users
1977 * unplug/replug that will clear all the error state.
1979 * note: everything running before here was guaranteed
1980 * to choke driver model style diagnostics. from here
1981 * on, they can work ... except in cleanup paths that
1982 * kick in after the ep0 descriptor is closed.
1984 fd->f_op = &ep0_io_operations;
1990 spin_unlock_irq (&dev->lock);
1991 pr_debug ("%s: %s fail %Zd, %p\n", shortname, __func__, value, dev);
1998 dev_open (struct inode *inode, struct file *fd)
2000 struct dev_data *dev = inode->i_private;
2003 spin_lock_irq(&dev->lock);
2004 if (dev->state == STATE_DEV_DISABLED) {
2006 dev->state = STATE_DEV_OPENED;
2007 fd->private_data = dev;
2011 spin_unlock_irq(&dev->lock);
2015 static const struct file_operations dev_init_operations = {
2016 .owner = THIS_MODULE,
2017 .llseek = no_llseek,
2020 .write = dev_config,
2021 .fasync = ep0_fasync,
2022 .unlocked_ioctl = dev_ioctl,
2023 .release = dev_release,
2026 /*----------------------------------------------------------------------*/
2028 /* FILESYSTEM AND SUPERBLOCK OPERATIONS
2030 * Mounting the filesystem creates a controller file, used first for
2031 * device configuration then later for event monitoring.
2035 /* FIXME PAM etc could set this security policy without mount options
2036 * if epfiles inherited ownership and permissons from ep0 ...
2039 static unsigned default_uid;
2040 static unsigned default_gid;
2041 static unsigned default_perm = S_IRUSR | S_IWUSR;
2043 module_param (default_uid, uint, 0644);
2044 module_param (default_gid, uint, 0644);
2045 module_param (default_perm, uint, 0644);
2048 static struct inode *
2049 gadgetfs_make_inode (struct super_block *sb,
2050 void *data, const struct file_operations *fops,
2053 struct inode *inode = new_inode (sb);
2056 inode->i_ino = get_next_ino();
2057 inode->i_mode = mode;
2058 inode->i_uid = default_uid;
2059 inode->i_gid = default_gid;
2060 inode->i_atime = inode->i_mtime = inode->i_ctime
2062 inode->i_private = data;
2063 inode->i_fop = fops;
2068 /* creates in fs root directory, so non-renamable and non-linkable.
2069 * so inode and dentry are paired, until device reconfig.
2071 static struct inode *
2072 gadgetfs_create_file (struct super_block *sb, char const *name,
2073 void *data, const struct file_operations *fops,
2074 struct dentry **dentry_p)
2076 struct dentry *dentry;
2077 struct inode *inode;
2079 dentry = d_alloc_name(sb->s_root, name);
2083 inode = gadgetfs_make_inode (sb, data, fops,
2084 S_IFREG | (default_perm & S_IRWXUGO));
2089 d_add (dentry, inode);
2094 static const struct super_operations gadget_fs_operations = {
2095 .statfs = simple_statfs,
2096 .drop_inode = generic_delete_inode,
2100 gadgetfs_fill_super (struct super_block *sb, void *opts, int silent)
2102 struct inode *inode;
2104 struct dev_data *dev;
2109 /* fake probe to determine $CHIP */
2110 (void) usb_gadget_probe_driver(&probe_driver, gadgetfs_probe);
2115 sb->s_blocksize = PAGE_CACHE_SIZE;
2116 sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
2117 sb->s_magic = GADGETFS_MAGIC;
2118 sb->s_op = &gadget_fs_operations;
2119 sb->s_time_gran = 1;
2122 inode = gadgetfs_make_inode (sb,
2123 NULL, &simple_dir_operations,
2124 S_IFDIR | S_IRUGO | S_IXUGO);
2127 inode->i_op = &simple_dir_inode_operations;
2128 if (!(d = d_alloc_root (inode)))
2132 /* the ep0 file is named after the controller we expect;
2133 * user mode code can use it for sanity checks, like we do.
2140 if (!gadgetfs_create_file (sb, CHIP,
2141 dev, &dev_init_operations,
2145 /* other endpoint files are available after hardware setup,
2146 * from binding to a controller.
2161 /* "mount -t gadgetfs path /dev/gadget" ends up here */
2162 static struct dentry *
2163 gadgetfs_mount (struct file_system_type *t, int flags,
2164 const char *path, void *opts)
2166 return mount_single (t, flags, opts, gadgetfs_fill_super);
2170 gadgetfs_kill_sb (struct super_block *sb)
2172 kill_litter_super (sb);
2174 put_dev (the_device);
2179 /*----------------------------------------------------------------------*/
2181 static struct file_system_type gadgetfs_type = {
2182 .owner = THIS_MODULE,
2184 .mount = gadgetfs_mount,
2185 .kill_sb = gadgetfs_kill_sb,
2188 /*----------------------------------------------------------------------*/
2190 static int __init init (void)
2194 status = register_filesystem (&gadgetfs_type);
2196 pr_info ("%s: %s, version " DRIVER_VERSION "\n",
2197 shortname, driver_desc);
2202 static void __exit cleanup (void)
2204 pr_debug ("unregister %s\n", shortname);
2205 unregister_filesystem (&gadgetfs_type);
2207 module_exit (cleanup);