2 * f_fs.c -- user mode file system API for USB composite function controllers
4 * Copyright (C) 2010 Samsung Electronics
5 * Author: Michal Nazarewicz <mina86@mina86.com>
7 * Based on inode.c (GadgetFS) which was:
8 * Copyright (C) 2003-2004 David Brownell
9 * Copyright (C) 2003 Agilent Technologies
11 * This program is free software; you can redistribute it and/or modify
12 * it under the terms of the GNU General Public License as published by
13 * the Free Software Foundation; either version 2 of the License, or
14 * (at your option) any later version.
19 /* #define VERBOSE_DEBUG */
21 #include <linux/blkdev.h>
22 #include <linux/pagemap.h>
23 #include <linux/export.h>
24 #include <linux/hid.h>
25 #include <linux/module.h>
26 #include <asm/unaligned.h>
28 #include <linux/usb/composite.h>
29 #include <linux/usb/functionfs.h>
31 #include <linux/aio.h>
32 #include <linux/mmu_context.h>
33 #include <linux/poll.h>
38 #define FUNCTIONFS_MAGIC 0xa647361 /* Chosen by a honest dice roll ;) */
40 /* Variable Length Array Macros **********************************************/
41 #define vla_group(groupname) size_t groupname##__next = 0
42 #define vla_group_size(groupname) groupname##__next
44 #define vla_item(groupname, type, name, n) \
45 size_t groupname##_##name##__offset = ({ \
46 size_t align_mask = __alignof__(type) - 1; \
47 size_t offset = (groupname##__next + align_mask) & ~align_mask;\
48 size_t size = (n) * sizeof(type); \
49 groupname##__next = offset + size; \
53 #define vla_item_with_sz(groupname, type, name, n) \
54 size_t groupname##_##name##__sz = (n) * sizeof(type); \
55 size_t groupname##_##name##__offset = ({ \
56 size_t align_mask = __alignof__(type) - 1; \
57 size_t offset = (groupname##__next + align_mask) & ~align_mask;\
58 size_t size = groupname##_##name##__sz; \
59 groupname##__next = offset + size; \
63 #define vla_ptr(ptr, groupname, name) \
64 ((void *) ((char *)ptr + groupname##_##name##__offset))
66 /* Reference counter handling */
67 static void ffs_data_get(struct ffs_data *ffs);
68 static void ffs_data_put(struct ffs_data *ffs);
69 /* Creates new ffs_data object. */
70 static struct ffs_data *__must_check ffs_data_new(void) __attribute__((malloc));
72 /* Opened counter handling. */
73 static void ffs_data_opened(struct ffs_data *ffs);
74 static void ffs_data_closed(struct ffs_data *ffs);
76 /* Called with ffs->mutex held; take over ownership of data. */
77 static int __must_check
78 __ffs_data_got_descs(struct ffs_data *ffs, char *data, size_t len);
79 static int __must_check
80 __ffs_data_got_strings(struct ffs_data *ffs, char *data, size_t len);
83 /* The function structure ***************************************************/
88 struct usb_configuration *conf;
89 struct usb_gadget *gadget;
94 short *interfaces_nums;
96 struct usb_function function;
100 static struct ffs_function *ffs_func_from_usb(struct usb_function *f)
102 return container_of(f, struct ffs_function, function);
106 static inline enum ffs_setup_state
107 ffs_setup_state_clear_cancelled(struct ffs_data *ffs)
109 return (enum ffs_setup_state)
110 cmpxchg(&ffs->setup_state, FFS_SETUP_CANCELLED, FFS_NO_SETUP);
114 static void ffs_func_eps_disable(struct ffs_function *func);
115 static int __must_check ffs_func_eps_enable(struct ffs_function *func);
117 static int ffs_func_bind(struct usb_configuration *,
118 struct usb_function *);
119 static int ffs_func_set_alt(struct usb_function *, unsigned, unsigned);
120 static void ffs_func_disable(struct usb_function *);
121 static int ffs_func_setup(struct usb_function *,
122 const struct usb_ctrlrequest *);
123 static void ffs_func_suspend(struct usb_function *);
124 static void ffs_func_resume(struct usb_function *);
127 static int ffs_func_revmap_ep(struct ffs_function *func, u8 num);
128 static int ffs_func_revmap_intf(struct ffs_function *func, u8 intf);
131 /* The endpoints structures *************************************************/
134 struct usb_ep *ep; /* P: ffs->eps_lock */
135 struct usb_request *req; /* P: epfile->mutex */
137 /* [0]: full speed, [1]: high speed, [2]: super speed */
138 struct usb_endpoint_descriptor *descs[3];
142 int status; /* P: epfile->mutex */
146 /* Protects ep->ep and ep->req. */
148 wait_queue_head_t wait;
150 struct ffs_data *ffs;
151 struct ffs_ep *ep; /* P: ffs->eps_lock */
153 struct dentry *dentry;
157 unsigned char in; /* P: ffs->eps_lock */
158 unsigned char isoc; /* P: ffs->eps_lock */
163 /* ffs_io_data structure ***************************************************/
170 const struct iovec *iovec;
171 unsigned long nr_segs;
175 struct mm_struct *mm;
176 struct work_struct work;
179 struct usb_request *req;
182 static int __must_check ffs_epfiles_create(struct ffs_data *ffs);
183 static void ffs_epfiles_destroy(struct ffs_epfile *epfiles, unsigned count);
185 static struct inode *__must_check
186 ffs_sb_create_file(struct super_block *sb, const char *name, void *data,
187 const struct file_operations *fops,
188 struct dentry **dentry_p);
190 /* Devices management *******************************************************/
192 DEFINE_MUTEX(ffs_lock);
193 EXPORT_SYMBOL(ffs_lock);
195 static struct ffs_dev *_ffs_find_dev(const char *name);
196 static struct ffs_dev *_ffs_alloc_dev(void);
197 static int _ffs_name_dev(struct ffs_dev *dev, const char *name);
198 static void _ffs_free_dev(struct ffs_dev *dev);
199 static void *ffs_acquire_dev(const char *dev_name);
200 static void ffs_release_dev(struct ffs_data *ffs_data);
201 static int ffs_ready(struct ffs_data *ffs);
202 static void ffs_closed(struct ffs_data *ffs);
204 /* Misc helper functions ****************************************************/
206 static int ffs_mutex_lock(struct mutex *mutex, unsigned nonblock)
207 __attribute__((warn_unused_result, nonnull));
208 static char *ffs_prepare_buffer(const char __user *buf, size_t len)
209 __attribute__((warn_unused_result, nonnull));
212 /* Control file aka ep0 *****************************************************/
214 static void ffs_ep0_complete(struct usb_ep *ep, struct usb_request *req)
216 struct ffs_data *ffs = req->context;
218 complete_all(&ffs->ep0req_completion);
221 static int __ffs_ep0_queue_wait(struct ffs_data *ffs, char *data, size_t len)
223 struct usb_request *req = ffs->ep0req;
226 req->zero = len < le16_to_cpu(ffs->ev.setup.wLength);
228 spin_unlock_irq(&ffs->ev.waitq.lock);
234 * UDC layer requires to provide a buffer even for ZLP, but should
235 * not use it at all. Let's provide some poisoned pointer to catch
236 * possible bug in the driver.
238 if (req->buf == NULL)
239 req->buf = (void *)0xDEADBABE;
241 reinit_completion(&ffs->ep0req_completion);
243 ret = usb_ep_queue(ffs->gadget->ep0, req, GFP_ATOMIC);
244 if (unlikely(ret < 0))
247 ret = wait_for_completion_interruptible(&ffs->ep0req_completion);
249 usb_ep_dequeue(ffs->gadget->ep0, req);
253 ffs->setup_state = FFS_NO_SETUP;
254 return req->status ? req->status : req->actual;
257 static int __ffs_ep0_stall(struct ffs_data *ffs)
259 if (ffs->ev.can_stall) {
260 pr_vdebug("ep0 stall\n");
261 usb_ep_set_halt(ffs->gadget->ep0);
262 ffs->setup_state = FFS_NO_SETUP;
265 pr_debug("bogus ep0 stall!\n");
270 static ssize_t ffs_ep0_write(struct file *file, const char __user *buf,
271 size_t len, loff_t *ptr)
273 struct ffs_data *ffs = file->private_data;
279 /* Fast check if setup was canceled */
280 if (ffs_setup_state_clear_cancelled(ffs) == FFS_SETUP_CANCELLED)
284 ret = ffs_mutex_lock(&ffs->mutex, file->f_flags & O_NONBLOCK);
285 if (unlikely(ret < 0))
289 switch (ffs->state) {
290 case FFS_READ_DESCRIPTORS:
291 case FFS_READ_STRINGS:
293 if (unlikely(len < 16)) {
298 data = ffs_prepare_buffer(buf, len);
305 if (ffs->state == FFS_READ_DESCRIPTORS) {
306 pr_info("read descriptors\n");
307 ret = __ffs_data_got_descs(ffs, data, len);
308 if (unlikely(ret < 0))
311 ffs->state = FFS_READ_STRINGS;
314 pr_info("read strings\n");
315 ret = __ffs_data_got_strings(ffs, data, len);
316 if (unlikely(ret < 0))
319 ret = ffs_epfiles_create(ffs);
321 ffs->state = FFS_CLOSING;
325 ffs->state = FFS_ACTIVE;
326 mutex_unlock(&ffs->mutex);
328 ret = ffs_ready(ffs);
329 if (unlikely(ret < 0)) {
330 ffs->state = FFS_CLOSING;
334 set_bit(FFS_FL_CALL_CLOSED_CALLBACK, &ffs->flags);
342 * We're called from user space, we can use _irq
343 * rather then _irqsave
345 spin_lock_irq(&ffs->ev.waitq.lock);
346 switch (ffs_setup_state_clear_cancelled(ffs)) {
347 case FFS_SETUP_CANCELLED:
355 case FFS_SETUP_PENDING:
359 /* FFS_SETUP_PENDING */
360 if (!(ffs->ev.setup.bRequestType & USB_DIR_IN)) {
361 spin_unlock_irq(&ffs->ev.waitq.lock);
362 ret = __ffs_ep0_stall(ffs);
366 /* FFS_SETUP_PENDING and not stall */
367 len = min(len, (size_t)le16_to_cpu(ffs->ev.setup.wLength));
369 spin_unlock_irq(&ffs->ev.waitq.lock);
371 data = ffs_prepare_buffer(buf, len);
377 spin_lock_irq(&ffs->ev.waitq.lock);
380 * We are guaranteed to be still in FFS_ACTIVE state
381 * but the state of setup could have changed from
382 * FFS_SETUP_PENDING to FFS_SETUP_CANCELLED so we need
383 * to check for that. If that happened we copied data
384 * from user space in vain but it's unlikely.
386 * For sure we are not in FFS_NO_SETUP since this is
387 * the only place FFS_SETUP_PENDING -> FFS_NO_SETUP
388 * transition can be performed and it's protected by
391 if (ffs_setup_state_clear_cancelled(ffs) ==
392 FFS_SETUP_CANCELLED) {
395 spin_unlock_irq(&ffs->ev.waitq.lock);
397 /* unlocks spinlock */
398 ret = __ffs_ep0_queue_wait(ffs, data, len);
408 mutex_unlock(&ffs->mutex);
412 static ssize_t __ffs_ep0_read_events(struct ffs_data *ffs, char __user *buf,
416 * We are holding ffs->ev.waitq.lock and ffs->mutex and we need
419 struct usb_functionfs_event events[n];
422 memset(events, 0, sizeof events);
425 events[i].type = ffs->ev.types[i];
426 if (events[i].type == FUNCTIONFS_SETUP) {
427 events[i].u.setup = ffs->ev.setup;
428 ffs->setup_state = FFS_SETUP_PENDING;
432 if (n < ffs->ev.count) {
434 memmove(ffs->ev.types, ffs->ev.types + n,
435 ffs->ev.count * sizeof *ffs->ev.types);
440 spin_unlock_irq(&ffs->ev.waitq.lock);
441 mutex_unlock(&ffs->mutex);
443 return unlikely(__copy_to_user(buf, events, sizeof events))
444 ? -EFAULT : sizeof events;
447 static ssize_t ffs_ep0_read(struct file *file, char __user *buf,
448 size_t len, loff_t *ptr)
450 struct ffs_data *ffs = file->private_data;
457 /* Fast check if setup was canceled */
458 if (ffs_setup_state_clear_cancelled(ffs) == FFS_SETUP_CANCELLED)
462 ret = ffs_mutex_lock(&ffs->mutex, file->f_flags & O_NONBLOCK);
463 if (unlikely(ret < 0))
467 if (ffs->state != FFS_ACTIVE) {
473 * We're called from user space, we can use _irq rather then
476 spin_lock_irq(&ffs->ev.waitq.lock);
478 switch (ffs_setup_state_clear_cancelled(ffs)) {
479 case FFS_SETUP_CANCELLED:
484 n = len / sizeof(struct usb_functionfs_event);
490 if ((file->f_flags & O_NONBLOCK) && !ffs->ev.count) {
495 if (wait_event_interruptible_exclusive_locked_irq(ffs->ev.waitq,
501 return __ffs_ep0_read_events(ffs, buf,
502 min(n, (size_t)ffs->ev.count));
504 case FFS_SETUP_PENDING:
505 if (ffs->ev.setup.bRequestType & USB_DIR_IN) {
506 spin_unlock_irq(&ffs->ev.waitq.lock);
507 ret = __ffs_ep0_stall(ffs);
511 len = min(len, (size_t)le16_to_cpu(ffs->ev.setup.wLength));
513 spin_unlock_irq(&ffs->ev.waitq.lock);
516 data = kmalloc(len, GFP_KERNEL);
517 if (unlikely(!data)) {
523 spin_lock_irq(&ffs->ev.waitq.lock);
525 /* See ffs_ep0_write() */
526 if (ffs_setup_state_clear_cancelled(ffs) ==
527 FFS_SETUP_CANCELLED) {
532 /* unlocks spinlock */
533 ret = __ffs_ep0_queue_wait(ffs, data, len);
534 if (likely(ret > 0) && unlikely(__copy_to_user(buf, data, len)))
543 spin_unlock_irq(&ffs->ev.waitq.lock);
545 mutex_unlock(&ffs->mutex);
550 static int ffs_ep0_open(struct inode *inode, struct file *file)
552 struct ffs_data *ffs = inode->i_private;
556 if (unlikely(ffs->state == FFS_CLOSING))
559 file->private_data = ffs;
560 ffs_data_opened(ffs);
565 static int ffs_ep0_release(struct inode *inode, struct file *file)
567 struct ffs_data *ffs = file->private_data;
571 ffs_data_closed(ffs);
576 static long ffs_ep0_ioctl(struct file *file, unsigned code, unsigned long value)
578 struct ffs_data *ffs = file->private_data;
579 struct usb_gadget *gadget = ffs->gadget;
584 if (code == FUNCTIONFS_INTERFACE_REVMAP) {
585 struct ffs_function *func = ffs->func;
586 ret = func ? ffs_func_revmap_intf(func, value) : -ENODEV;
587 } else if (gadget && gadget->ops->ioctl) {
588 ret = gadget->ops->ioctl(gadget, code, value);
596 static unsigned int ffs_ep0_poll(struct file *file, poll_table *wait)
598 struct ffs_data *ffs = file->private_data;
599 unsigned int mask = POLLWRNORM;
602 poll_wait(file, &ffs->ev.waitq, wait);
604 ret = ffs_mutex_lock(&ffs->mutex, file->f_flags & O_NONBLOCK);
605 if (unlikely(ret < 0))
608 switch (ffs->state) {
609 case FFS_READ_DESCRIPTORS:
610 case FFS_READ_STRINGS:
615 switch (ffs->setup_state) {
621 case FFS_SETUP_PENDING:
622 case FFS_SETUP_CANCELLED:
623 mask |= (POLLIN | POLLOUT);
630 mutex_unlock(&ffs->mutex);
635 static const struct file_operations ffs_ep0_operations = {
638 .open = ffs_ep0_open,
639 .write = ffs_ep0_write,
640 .read = ffs_ep0_read,
641 .release = ffs_ep0_release,
642 .unlocked_ioctl = ffs_ep0_ioctl,
643 .poll = ffs_ep0_poll,
647 /* "Normal" endpoints operations ********************************************/
649 static void ffs_epfile_io_complete(struct usb_ep *_ep, struct usb_request *req)
652 if (likely(req->context)) {
653 struct ffs_ep *ep = _ep->driver_data;
654 ep->status = req->status ? req->status : req->actual;
655 complete(req->context);
659 static void ffs_user_copy_worker(struct work_struct *work)
661 struct ffs_io_data *io_data = container_of(work, struct ffs_io_data,
663 int ret = io_data->req->status ? io_data->req->status :
664 io_data->req->actual;
666 if (io_data->read && ret > 0) {
670 for (i = 0; i < io_data->nr_segs; i++) {
671 if (unlikely(copy_to_user(io_data->iovec[i].iov_base,
673 io_data->iovec[i].iov_len))) {
677 pos += io_data->iovec[i].iov_len;
679 unuse_mm(io_data->mm);
682 aio_complete(io_data->kiocb, ret, ret);
684 usb_ep_free_request(io_data->ep, io_data->req);
686 io_data->kiocb->private = NULL;
688 kfree(io_data->iovec);
693 static void ffs_epfile_async_io_complete(struct usb_ep *_ep,
694 struct usb_request *req)
696 struct ffs_io_data *io_data = req->context;
700 INIT_WORK(&io_data->work, ffs_user_copy_worker);
701 schedule_work(&io_data->work);
704 static ssize_t ffs_epfile_io(struct file *file, struct ffs_io_data *io_data)
706 struct ffs_epfile *epfile = file->private_data;
709 ssize_t ret, data_len;
712 /* Are we still active? */
713 if (WARN_ON(epfile->ffs->state != FFS_ACTIVE)) {
718 /* Wait for endpoint to be enabled */
721 if (file->f_flags & O_NONBLOCK) {
726 ret = wait_event_interruptible(epfile->wait, (ep = epfile->ep));
734 halt = (!io_data->read == !epfile->in);
735 if (halt && epfile->isoc) {
740 /* Allocate & copy */
743 * if we _do_ wait above, the epfile->ffs->gadget might be NULL
744 * before the waiting completes, so do not assign to 'gadget' earlier
746 struct usb_gadget *gadget = epfile->ffs->gadget;
749 * Controller may require buffer size to be aligned to
750 * maxpacketsize of an out endpoint.
752 data_len = io_data->read ?
753 usb_ep_align_maybe(gadget, ep->ep, io_data->len) :
756 data = kmalloc(data_len, GFP_KERNEL);
759 if (io_data->aio && !io_data->read) {
762 for (i = 0; i < io_data->nr_segs; i++) {
763 if (unlikely(copy_from_user(&data[pos],
764 io_data->iovec[i].iov_base,
765 io_data->iovec[i].iov_len))) {
769 pos += io_data->iovec[i].iov_len;
772 if (!io_data->read &&
773 unlikely(__copy_from_user(data, io_data->buf,
781 /* We will be using request */
782 ret = ffs_mutex_lock(&epfile->mutex, file->f_flags & O_NONBLOCK);
786 spin_lock_irq(&epfile->ffs->eps_lock);
788 if (epfile->ep != ep) {
789 /* In the meantime, endpoint got disabled or changed. */
791 spin_unlock_irq(&epfile->ffs->eps_lock);
794 if (likely(epfile->ep == ep) && !WARN_ON(!ep->ep))
795 usb_ep_set_halt(ep->ep);
796 spin_unlock_irq(&epfile->ffs->eps_lock);
799 /* Fire the request */
800 struct usb_request *req;
803 req = usb_ep_alloc_request(ep->ep, GFP_KERNEL);
808 req->length = io_data->len;
811 io_data->ep = ep->ep;
814 req->context = io_data;
815 req->complete = ffs_epfile_async_io_complete;
817 ret = usb_ep_queue(ep->ep, req, GFP_ATOMIC);
819 usb_ep_free_request(ep->ep, req);
824 spin_unlock_irq(&epfile->ffs->eps_lock);
826 DECLARE_COMPLETION_ONSTACK(done);
830 req->length = io_data->len;
832 req->context = &done;
833 req->complete = ffs_epfile_io_complete;
835 ret = usb_ep_queue(ep->ep, req, GFP_ATOMIC);
837 spin_unlock_irq(&epfile->ffs->eps_lock);
839 if (unlikely(ret < 0)) {
842 wait_for_completion_interruptible(&done))) {
844 usb_ep_dequeue(ep->ep, req);
847 * XXX We may end up silently droping data
848 * here. Since data_len (i.e. req->length) may
849 * be bigger than len (after being rounded up
850 * to maxpacketsize), we may end up with more
851 * data then user space has space for.
854 if (io_data->read && ret > 0) {
855 ret = min_t(size_t, ret, io_data->len);
857 if (unlikely(copy_to_user(io_data->buf,
866 mutex_unlock(&epfile->mutex);
874 ffs_epfile_write(struct file *file, const char __user *buf, size_t len,
877 struct ffs_io_data io_data;
882 io_data.read = false;
883 io_data.buf = (char * __user)buf;
886 return ffs_epfile_io(file, &io_data);
890 ffs_epfile_read(struct file *file, char __user *buf, size_t len, loff_t *ptr)
892 struct ffs_io_data io_data;
901 return ffs_epfile_io(file, &io_data);
905 ffs_epfile_open(struct inode *inode, struct file *file)
907 struct ffs_epfile *epfile = inode->i_private;
911 if (WARN_ON(epfile->ffs->state != FFS_ACTIVE))
914 file->private_data = epfile;
915 ffs_data_opened(epfile->ffs);
920 static int ffs_aio_cancel(struct kiocb *kiocb)
922 struct ffs_io_data *io_data = kiocb->private;
923 struct ffs_epfile *epfile = kiocb->ki_filp->private_data;
928 spin_lock_irq(&epfile->ffs->eps_lock);
930 if (likely(io_data && io_data->ep && io_data->req))
931 value = usb_ep_dequeue(io_data->ep, io_data->req);
935 spin_unlock_irq(&epfile->ffs->eps_lock);
940 static ssize_t ffs_epfile_aio_write(struct kiocb *kiocb,
941 const struct iovec *iovec,
942 unsigned long nr_segs, loff_t loff)
944 struct ffs_io_data *io_data;
948 io_data = kmalloc(sizeof(*io_data), GFP_KERNEL);
949 if (unlikely(!io_data))
953 io_data->read = false;
954 io_data->kiocb = kiocb;
955 io_data->iovec = iovec;
956 io_data->nr_segs = nr_segs;
957 io_data->len = kiocb->ki_nbytes;
958 io_data->mm = current->mm;
960 kiocb->private = io_data;
962 kiocb_set_cancel_fn(kiocb, ffs_aio_cancel);
964 return ffs_epfile_io(kiocb->ki_filp, io_data);
967 static ssize_t ffs_epfile_aio_read(struct kiocb *kiocb,
968 const struct iovec *iovec,
969 unsigned long nr_segs, loff_t loff)
971 struct ffs_io_data *io_data;
972 struct iovec *iovec_copy;
976 iovec_copy = kmalloc_array(nr_segs, sizeof(*iovec_copy), GFP_KERNEL);
977 if (unlikely(!iovec_copy))
980 memcpy(iovec_copy, iovec, sizeof(struct iovec)*nr_segs);
982 io_data = kmalloc(sizeof(*io_data), GFP_KERNEL);
983 if (unlikely(!io_data)) {
989 io_data->read = true;
990 io_data->kiocb = kiocb;
991 io_data->iovec = iovec_copy;
992 io_data->nr_segs = nr_segs;
993 io_data->len = kiocb->ki_nbytes;
994 io_data->mm = current->mm;
996 kiocb->private = io_data;
998 kiocb_set_cancel_fn(kiocb, ffs_aio_cancel);
1000 return ffs_epfile_io(kiocb->ki_filp, io_data);
1004 ffs_epfile_release(struct inode *inode, struct file *file)
1006 struct ffs_epfile *epfile = inode->i_private;
1010 ffs_data_closed(epfile->ffs);
1015 static long ffs_epfile_ioctl(struct file *file, unsigned code,
1016 unsigned long value)
1018 struct ffs_epfile *epfile = file->private_data;
1023 if (WARN_ON(epfile->ffs->state != FFS_ACTIVE))
1026 spin_lock_irq(&epfile->ffs->eps_lock);
1027 if (likely(epfile->ep)) {
1029 case FUNCTIONFS_FIFO_STATUS:
1030 ret = usb_ep_fifo_status(epfile->ep->ep);
1032 case FUNCTIONFS_FIFO_FLUSH:
1033 usb_ep_fifo_flush(epfile->ep->ep);
1036 case FUNCTIONFS_CLEAR_HALT:
1037 ret = usb_ep_clear_halt(epfile->ep->ep);
1039 case FUNCTIONFS_ENDPOINT_REVMAP:
1040 ret = epfile->ep->num;
1048 spin_unlock_irq(&epfile->ffs->eps_lock);
1053 static const struct file_operations ffs_epfile_operations = {
1054 .llseek = no_llseek,
1056 .open = ffs_epfile_open,
1057 .write = ffs_epfile_write,
1058 .read = ffs_epfile_read,
1059 .aio_write = ffs_epfile_aio_write,
1060 .aio_read = ffs_epfile_aio_read,
1061 .release = ffs_epfile_release,
1062 .unlocked_ioctl = ffs_epfile_ioctl,
1066 /* File system and super block operations ***********************************/
1069 * Mounting the file system creates a controller file, used first for
1070 * function configuration then later for event monitoring.
1073 static struct inode *__must_check
1074 ffs_sb_make_inode(struct super_block *sb, void *data,
1075 const struct file_operations *fops,
1076 const struct inode_operations *iops,
1077 struct ffs_file_perms *perms)
1079 struct inode *inode;
1083 inode = new_inode(sb);
1085 if (likely(inode)) {
1086 struct timespec current_time = CURRENT_TIME;
1088 inode->i_ino = get_next_ino();
1089 inode->i_mode = perms->mode;
1090 inode->i_uid = perms->uid;
1091 inode->i_gid = perms->gid;
1092 inode->i_atime = current_time;
1093 inode->i_mtime = current_time;
1094 inode->i_ctime = current_time;
1095 inode->i_private = data;
1097 inode->i_fop = fops;
1105 /* Create "regular" file */
1106 static struct inode *ffs_sb_create_file(struct super_block *sb,
1107 const char *name, void *data,
1108 const struct file_operations *fops,
1109 struct dentry **dentry_p)
1111 struct ffs_data *ffs = sb->s_fs_info;
1112 struct dentry *dentry;
1113 struct inode *inode;
1117 dentry = d_alloc_name(sb->s_root, name);
1118 if (unlikely(!dentry))
1121 inode = ffs_sb_make_inode(sb, data, fops, NULL, &ffs->file_perms);
1122 if (unlikely(!inode)) {
1127 d_add(dentry, inode);
1135 static const struct super_operations ffs_sb_operations = {
1136 .statfs = simple_statfs,
1137 .drop_inode = generic_delete_inode,
1140 struct ffs_sb_fill_data {
1141 struct ffs_file_perms perms;
1143 const char *dev_name;
1144 struct ffs_data *ffs_data;
1147 static int ffs_sb_fill(struct super_block *sb, void *_data, int silent)
1149 struct ffs_sb_fill_data *data = _data;
1150 struct inode *inode;
1151 struct ffs_data *ffs = data->ffs_data;
1156 data->ffs_data = NULL;
1157 sb->s_fs_info = ffs;
1158 sb->s_blocksize = PAGE_CACHE_SIZE;
1159 sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
1160 sb->s_magic = FUNCTIONFS_MAGIC;
1161 sb->s_op = &ffs_sb_operations;
1162 sb->s_time_gran = 1;
1165 data->perms.mode = data->root_mode;
1166 inode = ffs_sb_make_inode(sb, NULL,
1167 &simple_dir_operations,
1168 &simple_dir_inode_operations,
1170 sb->s_root = d_make_root(inode);
1171 if (unlikely(!sb->s_root))
1175 if (unlikely(!ffs_sb_create_file(sb, "ep0", ffs,
1176 &ffs_ep0_operations, NULL)))
1182 static int ffs_fs_parse_opts(struct ffs_sb_fill_data *data, char *opts)
1186 if (!opts || !*opts)
1190 unsigned long value;
1194 comma = strchr(opts, ',');
1199 eq = strchr(opts, '=');
1200 if (unlikely(!eq)) {
1201 pr_err("'=' missing in %s\n", opts);
1207 if (kstrtoul(eq + 1, 0, &value)) {
1208 pr_err("%s: invalid value: %s\n", opts, eq + 1);
1212 /* Interpret option */
1213 switch (eq - opts) {
1215 if (!memcmp(opts, "rmode", 5))
1216 data->root_mode = (value & 0555) | S_IFDIR;
1217 else if (!memcmp(opts, "fmode", 5))
1218 data->perms.mode = (value & 0666) | S_IFREG;
1224 if (!memcmp(opts, "mode", 4)) {
1225 data->root_mode = (value & 0555) | S_IFDIR;
1226 data->perms.mode = (value & 0666) | S_IFREG;
1233 if (!memcmp(opts, "uid", 3)) {
1234 data->perms.uid = make_kuid(current_user_ns(), value);
1235 if (!uid_valid(data->perms.uid)) {
1236 pr_err("%s: unmapped value: %lu\n", opts, value);
1239 } else if (!memcmp(opts, "gid", 3)) {
1240 data->perms.gid = make_kgid(current_user_ns(), value);
1241 if (!gid_valid(data->perms.gid)) {
1242 pr_err("%s: unmapped value: %lu\n", opts, value);
1252 pr_err("%s: invalid option\n", opts);
1256 /* Next iteration */
1265 /* "mount -t functionfs dev_name /dev/function" ends up here */
1267 static struct dentry *
1268 ffs_fs_mount(struct file_system_type *t, int flags,
1269 const char *dev_name, void *opts)
1271 struct ffs_sb_fill_data data = {
1273 .mode = S_IFREG | 0600,
1274 .uid = GLOBAL_ROOT_UID,
1275 .gid = GLOBAL_ROOT_GID,
1277 .root_mode = S_IFDIR | 0500,
1282 struct ffs_data *ffs;
1286 ret = ffs_fs_parse_opts(&data, opts);
1287 if (unlikely(ret < 0))
1288 return ERR_PTR(ret);
1290 ffs = ffs_data_new();
1292 return ERR_PTR(-ENOMEM);
1293 ffs->file_perms = data.perms;
1295 ffs->dev_name = kstrdup(dev_name, GFP_KERNEL);
1296 if (unlikely(!ffs->dev_name)) {
1298 return ERR_PTR(-ENOMEM);
1301 ffs_dev = ffs_acquire_dev(dev_name);
1302 if (IS_ERR(ffs_dev)) {
1304 return ERR_CAST(ffs_dev);
1306 ffs->private_data = ffs_dev;
1307 data.ffs_data = ffs;
1309 rv = mount_nodev(t, flags, &data, ffs_sb_fill);
1310 if (IS_ERR(rv) && data.ffs_data) {
1311 ffs_release_dev(data.ffs_data);
1312 ffs_data_put(data.ffs_data);
1318 ffs_fs_kill_sb(struct super_block *sb)
1322 kill_litter_super(sb);
1323 if (sb->s_fs_info) {
1324 ffs_release_dev(sb->s_fs_info);
1325 ffs_data_put(sb->s_fs_info);
1329 static struct file_system_type ffs_fs_type = {
1330 .owner = THIS_MODULE,
1331 .name = "functionfs",
1332 .mount = ffs_fs_mount,
1333 .kill_sb = ffs_fs_kill_sb,
1335 MODULE_ALIAS_FS("functionfs");
1338 /* Driver's main init/cleanup functions *************************************/
1340 static int functionfs_init(void)
1346 ret = register_filesystem(&ffs_fs_type);
1348 pr_info("file system registered\n");
1350 pr_err("failed registering file system (%d)\n", ret);
1355 static void functionfs_cleanup(void)
1359 pr_info("unloading\n");
1360 unregister_filesystem(&ffs_fs_type);
1364 /* ffs_data and ffs_function construction and destruction code **************/
1366 static void ffs_data_clear(struct ffs_data *ffs);
1367 static void ffs_data_reset(struct ffs_data *ffs);
1369 static void ffs_data_get(struct ffs_data *ffs)
1373 atomic_inc(&ffs->ref);
1376 static void ffs_data_opened(struct ffs_data *ffs)
1380 atomic_inc(&ffs->ref);
1381 atomic_inc(&ffs->opened);
1384 static void ffs_data_put(struct ffs_data *ffs)
1388 if (unlikely(atomic_dec_and_test(&ffs->ref))) {
1389 pr_info("%s(): freeing\n", __func__);
1390 ffs_data_clear(ffs);
1391 BUG_ON(waitqueue_active(&ffs->ev.waitq) ||
1392 waitqueue_active(&ffs->ep0req_completion.wait));
1393 kfree(ffs->dev_name);
1398 static void ffs_data_closed(struct ffs_data *ffs)
1402 if (atomic_dec_and_test(&ffs->opened)) {
1403 ffs->state = FFS_CLOSING;
1404 ffs_data_reset(ffs);
1410 static struct ffs_data *ffs_data_new(void)
1412 struct ffs_data *ffs = kzalloc(sizeof *ffs, GFP_KERNEL);
1418 atomic_set(&ffs->ref, 1);
1419 atomic_set(&ffs->opened, 0);
1420 ffs->state = FFS_READ_DESCRIPTORS;
1421 mutex_init(&ffs->mutex);
1422 spin_lock_init(&ffs->eps_lock);
1423 init_waitqueue_head(&ffs->ev.waitq);
1424 init_completion(&ffs->ep0req_completion);
1426 /* XXX REVISIT need to update it in some places, or do we? */
1427 ffs->ev.can_stall = 1;
1432 static void ffs_data_clear(struct ffs_data *ffs)
1436 if (test_and_clear_bit(FFS_FL_CALL_CLOSED_CALLBACK, &ffs->flags))
1439 BUG_ON(ffs->gadget);
1442 ffs_epfiles_destroy(ffs->epfiles, ffs->eps_count);
1444 kfree(ffs->raw_descs_data);
1445 kfree(ffs->raw_strings);
1446 kfree(ffs->stringtabs);
1449 static void ffs_data_reset(struct ffs_data *ffs)
1453 ffs_data_clear(ffs);
1455 ffs->epfiles = NULL;
1456 ffs->raw_descs_data = NULL;
1457 ffs->raw_descs = NULL;
1458 ffs->raw_strings = NULL;
1459 ffs->stringtabs = NULL;
1461 ffs->raw_descs_length = 0;
1462 ffs->fs_descs_count = 0;
1463 ffs->hs_descs_count = 0;
1464 ffs->ss_descs_count = 0;
1466 ffs->strings_count = 0;
1467 ffs->interfaces_count = 0;
1472 ffs->state = FFS_READ_DESCRIPTORS;
1473 ffs->setup_state = FFS_NO_SETUP;
1478 static int functionfs_bind(struct ffs_data *ffs, struct usb_composite_dev *cdev)
1480 struct usb_gadget_strings **lang;
1485 if (WARN_ON(ffs->state != FFS_ACTIVE
1486 || test_and_set_bit(FFS_FL_BOUND, &ffs->flags)))
1489 first_id = usb_string_ids_n(cdev, ffs->strings_count);
1490 if (unlikely(first_id < 0))
1493 ffs->ep0req = usb_ep_alloc_request(cdev->gadget->ep0, GFP_KERNEL);
1494 if (unlikely(!ffs->ep0req))
1496 ffs->ep0req->complete = ffs_ep0_complete;
1497 ffs->ep0req->context = ffs;
1499 lang = ffs->stringtabs;
1500 for (lang = ffs->stringtabs; *lang; ++lang) {
1501 struct usb_string *str = (*lang)->strings;
1503 for (; str->s; ++id, ++str)
1507 ffs->gadget = cdev->gadget;
1512 static void functionfs_unbind(struct ffs_data *ffs)
1516 if (!WARN_ON(!ffs->gadget)) {
1517 usb_ep_free_request(ffs->gadget->ep0, ffs->ep0req);
1520 clear_bit(FFS_FL_BOUND, &ffs->flags);
1525 static int ffs_epfiles_create(struct ffs_data *ffs)
1527 struct ffs_epfile *epfile, *epfiles;
1532 count = ffs->eps_count;
1533 epfiles = kcalloc(count, sizeof(*epfiles), GFP_KERNEL);
1538 for (i = 1; i <= count; ++i, ++epfile) {
1540 mutex_init(&epfile->mutex);
1541 init_waitqueue_head(&epfile->wait);
1542 sprintf(epfiles->name, "ep%u", i);
1543 if (!unlikely(ffs_sb_create_file(ffs->sb, epfiles->name, epfile,
1544 &ffs_epfile_operations,
1545 &epfile->dentry))) {
1546 ffs_epfiles_destroy(epfiles, i - 1);
1551 ffs->epfiles = epfiles;
1555 static void ffs_epfiles_destroy(struct ffs_epfile *epfiles, unsigned count)
1557 struct ffs_epfile *epfile = epfiles;
1561 for (; count; --count, ++epfile) {
1562 BUG_ON(mutex_is_locked(&epfile->mutex) ||
1563 waitqueue_active(&epfile->wait));
1564 if (epfile->dentry) {
1565 d_delete(epfile->dentry);
1566 dput(epfile->dentry);
1567 epfile->dentry = NULL;
1575 static void ffs_func_eps_disable(struct ffs_function *func)
1577 struct ffs_ep *ep = func->eps;
1578 struct ffs_epfile *epfile = func->ffs->epfiles;
1579 unsigned count = func->ffs->eps_count;
1580 unsigned long flags;
1582 spin_lock_irqsave(&func->ffs->eps_lock, flags);
1584 /* pending requests get nuked */
1586 usb_ep_disable(ep->ep);
1592 spin_unlock_irqrestore(&func->ffs->eps_lock, flags);
1595 static int ffs_func_eps_enable(struct ffs_function *func)
1597 struct ffs_data *ffs = func->ffs;
1598 struct ffs_ep *ep = func->eps;
1599 struct ffs_epfile *epfile = ffs->epfiles;
1600 unsigned count = ffs->eps_count;
1601 unsigned long flags;
1604 spin_lock_irqsave(&func->ffs->eps_lock, flags);
1606 struct usb_endpoint_descriptor *ds;
1609 if (ffs->gadget->speed == USB_SPEED_SUPER)
1611 else if (ffs->gadget->speed == USB_SPEED_HIGH)
1616 /* fall-back to lower speed if desc missing for current speed */
1618 ds = ep->descs[desc_idx];
1619 } while (!ds && --desc_idx >= 0);
1626 ep->ep->driver_data = ep;
1628 ret = usb_ep_enable(ep->ep);
1631 epfile->in = usb_endpoint_dir_in(ds);
1632 epfile->isoc = usb_endpoint_xfer_isoc(ds);
1637 wake_up(&epfile->wait);
1642 spin_unlock_irqrestore(&func->ffs->eps_lock, flags);
1648 /* Parsing and building descriptors and strings *****************************/
1651 * This validates if data pointed by data is a valid USB descriptor as
1652 * well as record how many interfaces, endpoints and strings are
1653 * required by given configuration. Returns address after the
1654 * descriptor or NULL if data is invalid.
1657 enum ffs_entity_type {
1658 FFS_DESCRIPTOR, FFS_INTERFACE, FFS_STRING, FFS_ENDPOINT
1661 typedef int (*ffs_entity_callback)(enum ffs_entity_type entity,
1663 struct usb_descriptor_header *desc,
1666 static int __must_check ffs_do_desc(char *data, unsigned len,
1667 ffs_entity_callback entity, void *priv)
1669 struct usb_descriptor_header *_ds = (void *)data;
1675 /* At least two bytes are required: length and type */
1677 pr_vdebug("descriptor too short\n");
1681 /* If we have at least as many bytes as the descriptor takes? */
1682 length = _ds->bLength;
1684 pr_vdebug("descriptor longer then available data\n");
1688 #define __entity_check_INTERFACE(val) 1
1689 #define __entity_check_STRING(val) (val)
1690 #define __entity_check_ENDPOINT(val) ((val) & USB_ENDPOINT_NUMBER_MASK)
1691 #define __entity(type, val) do { \
1692 pr_vdebug("entity " #type "(%02x)\n", (val)); \
1693 if (unlikely(!__entity_check_ ##type(val))) { \
1694 pr_vdebug("invalid entity's value\n"); \
1697 ret = entity(FFS_ ##type, &val, _ds, priv); \
1698 if (unlikely(ret < 0)) { \
1699 pr_debug("entity " #type "(%02x); ret = %d\n", \
1705 /* Parse descriptor depending on type. */
1706 switch (_ds->bDescriptorType) {
1710 case USB_DT_DEVICE_QUALIFIER:
1711 /* function can't have any of those */
1712 pr_vdebug("descriptor reserved for gadget: %d\n",
1713 _ds->bDescriptorType);
1716 case USB_DT_INTERFACE: {
1717 struct usb_interface_descriptor *ds = (void *)_ds;
1718 pr_vdebug("interface descriptor\n");
1719 if (length != sizeof *ds)
1722 __entity(INTERFACE, ds->bInterfaceNumber);
1724 __entity(STRING, ds->iInterface);
1728 case USB_DT_ENDPOINT: {
1729 struct usb_endpoint_descriptor *ds = (void *)_ds;
1730 pr_vdebug("endpoint descriptor\n");
1731 if (length != USB_DT_ENDPOINT_SIZE &&
1732 length != USB_DT_ENDPOINT_AUDIO_SIZE)
1734 __entity(ENDPOINT, ds->bEndpointAddress);
1739 pr_vdebug("hid descriptor\n");
1740 if (length != sizeof(struct hid_descriptor))
1745 if (length != sizeof(struct usb_otg_descriptor))
1749 case USB_DT_INTERFACE_ASSOCIATION: {
1750 struct usb_interface_assoc_descriptor *ds = (void *)_ds;
1751 pr_vdebug("interface association descriptor\n");
1752 if (length != sizeof *ds)
1755 __entity(STRING, ds->iFunction);
1759 case USB_DT_SS_ENDPOINT_COMP:
1760 pr_vdebug("EP SS companion descriptor\n");
1761 if (length != sizeof(struct usb_ss_ep_comp_descriptor))
1765 case USB_DT_OTHER_SPEED_CONFIG:
1766 case USB_DT_INTERFACE_POWER:
1768 case USB_DT_SECURITY:
1769 case USB_DT_CS_RADIO_CONTROL:
1771 pr_vdebug("unimplemented descriptor: %d\n", _ds->bDescriptorType);
1775 /* We should never be here */
1776 pr_vdebug("unknown descriptor: %d\n", _ds->bDescriptorType);
1780 pr_vdebug("invalid length: %d (descriptor %d)\n",
1781 _ds->bLength, _ds->bDescriptorType);
1786 #undef __entity_check_DESCRIPTOR
1787 #undef __entity_check_INTERFACE
1788 #undef __entity_check_STRING
1789 #undef __entity_check_ENDPOINT
1794 static int __must_check ffs_do_descs(unsigned count, char *data, unsigned len,
1795 ffs_entity_callback entity, void *priv)
1797 const unsigned _len = len;
1798 unsigned long num = 0;
1808 /* Record "descriptor" entity */
1809 ret = entity(FFS_DESCRIPTOR, (u8 *)num, (void *)data, priv);
1810 if (unlikely(ret < 0)) {
1811 pr_debug("entity DESCRIPTOR(%02lx); ret = %d\n",
1819 ret = ffs_do_desc(data, len, entity, priv);
1820 if (unlikely(ret < 0)) {
1821 pr_debug("%s returns %d\n", __func__, ret);
1831 static int __ffs_data_do_entity(enum ffs_entity_type type,
1832 u8 *valuep, struct usb_descriptor_header *desc,
1835 struct ffs_data *ffs = priv;
1840 case FFS_DESCRIPTOR:
1845 * Interfaces are indexed from zero so if we
1846 * encountered interface "n" then there are at least
1849 if (*valuep >= ffs->interfaces_count)
1850 ffs->interfaces_count = *valuep + 1;
1855 * Strings are indexed from 1 (0 is magic ;) reserved
1856 * for languages list or some such)
1858 if (*valuep > ffs->strings_count)
1859 ffs->strings_count = *valuep;
1863 /* Endpoints are indexed from 1 as well. */
1864 if ((*valuep & USB_ENDPOINT_NUMBER_MASK) > ffs->eps_count)
1865 ffs->eps_count = (*valuep & USB_ENDPOINT_NUMBER_MASK);
1872 static int __ffs_data_got_descs(struct ffs_data *ffs,
1873 char *const _data, size_t len)
1875 char *data = _data, *raw_descs;
1876 unsigned counts[3], flags;
1877 int ret = -EINVAL, i;
1881 if (get_unaligned_le32(data + 4) != len)
1884 switch (get_unaligned_le32(data)) {
1885 case FUNCTIONFS_DESCRIPTORS_MAGIC:
1886 flags = FUNCTIONFS_HAS_FS_DESC | FUNCTIONFS_HAS_HS_DESC;
1890 case FUNCTIONFS_DESCRIPTORS_MAGIC_V2:
1891 flags = get_unaligned_le32(data + 8);
1892 if (flags & ~(FUNCTIONFS_HAS_FS_DESC |
1893 FUNCTIONFS_HAS_HS_DESC |
1894 FUNCTIONFS_HAS_SS_DESC)) {
1905 /* Read fs_count, hs_count and ss_count (if present) */
1906 for (i = 0; i < 3; ++i) {
1907 if (!(flags & (1 << i))) {
1909 } else if (len < 4) {
1912 counts[i] = get_unaligned_le32(data);
1918 /* Read descriptors */
1920 for (i = 0; i < 3; ++i) {
1923 ret = ffs_do_descs(counts[i], data, len,
1924 __ffs_data_do_entity, ffs);
1931 if (raw_descs == data || len) {
1936 ffs->raw_descs_data = _data;
1937 ffs->raw_descs = raw_descs;
1938 ffs->raw_descs_length = data - raw_descs;
1939 ffs->fs_descs_count = counts[0];
1940 ffs->hs_descs_count = counts[1];
1941 ffs->ss_descs_count = counts[2];
1950 static int __ffs_data_got_strings(struct ffs_data *ffs,
1951 char *const _data, size_t len)
1953 u32 str_count, needed_count, lang_count;
1954 struct usb_gadget_strings **stringtabs, *t;
1955 struct usb_string *strings, *s;
1956 const char *data = _data;
1960 if (unlikely(get_unaligned_le32(data) != FUNCTIONFS_STRINGS_MAGIC ||
1961 get_unaligned_le32(data + 4) != len))
1963 str_count = get_unaligned_le32(data + 8);
1964 lang_count = get_unaligned_le32(data + 12);
1966 /* if one is zero the other must be zero */
1967 if (unlikely(!str_count != !lang_count))
1970 /* Do we have at least as many strings as descriptors need? */
1971 needed_count = ffs->strings_count;
1972 if (unlikely(str_count < needed_count))
1976 * If we don't need any strings just return and free all
1979 if (!needed_count) {
1984 /* Allocate everything in one chunk so there's less maintenance. */
1988 vla_item(d, struct usb_gadget_strings *, stringtabs,
1990 vla_item(d, struct usb_gadget_strings, stringtab, lang_count);
1991 vla_item(d, struct usb_string, strings,
1992 lang_count*(needed_count+1));
1994 char *vlabuf = kmalloc(vla_group_size(d), GFP_KERNEL);
1996 if (unlikely(!vlabuf)) {
2001 /* Initialize the VLA pointers */
2002 stringtabs = vla_ptr(vlabuf, d, stringtabs);
2003 t = vla_ptr(vlabuf, d, stringtab);
2006 *stringtabs++ = t++;
2010 /* stringtabs = vlabuf = d_stringtabs for later kfree */
2011 stringtabs = vla_ptr(vlabuf, d, stringtabs);
2012 t = vla_ptr(vlabuf, d, stringtab);
2013 s = vla_ptr(vlabuf, d, strings);
2017 /* For each language */
2021 do { /* lang_count > 0 so we can use do-while */
2022 unsigned needed = needed_count;
2024 if (unlikely(len < 3))
2026 t->language = get_unaligned_le16(data);
2033 /* For each string */
2034 do { /* str_count > 0 so we can use do-while */
2035 size_t length = strnlen(data, len);
2037 if (unlikely(length == len))
2041 * User may provide more strings then we need,
2042 * if that's the case we simply ignore the
2045 if (likely(needed)) {
2047 * s->id will be set while adding
2048 * function to configuration so for
2049 * now just leave garbage here.
2058 } while (--str_count);
2060 s->id = 0; /* terminator */
2064 } while (--lang_count);
2066 /* Some garbage left? */
2071 ffs->stringtabs = stringtabs;
2072 ffs->raw_strings = _data;
2084 /* Events handling and management *******************************************/
2086 static void __ffs_event_add(struct ffs_data *ffs,
2087 enum usb_functionfs_event_type type)
2089 enum usb_functionfs_event_type rem_type1, rem_type2 = type;
2093 * Abort any unhandled setup
2095 * We do not need to worry about some cmpxchg() changing value
2096 * of ffs->setup_state without holding the lock because when
2097 * state is FFS_SETUP_PENDING cmpxchg() in several places in
2098 * the source does nothing.
2100 if (ffs->setup_state == FFS_SETUP_PENDING)
2101 ffs->setup_state = FFS_SETUP_CANCELLED;
2104 case FUNCTIONFS_RESUME:
2105 rem_type2 = FUNCTIONFS_SUSPEND;
2107 case FUNCTIONFS_SUSPEND:
2108 case FUNCTIONFS_SETUP:
2110 /* Discard all similar events */
2113 case FUNCTIONFS_BIND:
2114 case FUNCTIONFS_UNBIND:
2115 case FUNCTIONFS_DISABLE:
2116 case FUNCTIONFS_ENABLE:
2117 /* Discard everything other then power management. */
2118 rem_type1 = FUNCTIONFS_SUSPEND;
2119 rem_type2 = FUNCTIONFS_RESUME;
2128 u8 *ev = ffs->ev.types, *out = ev;
2129 unsigned n = ffs->ev.count;
2130 for (; n; --n, ++ev)
2131 if ((*ev == rem_type1 || *ev == rem_type2) == neg)
2134 pr_vdebug("purging event %d\n", *ev);
2135 ffs->ev.count = out - ffs->ev.types;
2138 pr_vdebug("adding event %d\n", type);
2139 ffs->ev.types[ffs->ev.count++] = type;
2140 wake_up_locked(&ffs->ev.waitq);
2143 static void ffs_event_add(struct ffs_data *ffs,
2144 enum usb_functionfs_event_type type)
2146 unsigned long flags;
2147 spin_lock_irqsave(&ffs->ev.waitq.lock, flags);
2148 __ffs_event_add(ffs, type);
2149 spin_unlock_irqrestore(&ffs->ev.waitq.lock, flags);
2153 /* Bind/unbind USB function hooks *******************************************/
2155 static int __ffs_func_bind_do_descs(enum ffs_entity_type type, u8 *valuep,
2156 struct usb_descriptor_header *desc,
2159 struct usb_endpoint_descriptor *ds = (void *)desc;
2160 struct ffs_function *func = priv;
2161 struct ffs_ep *ffs_ep;
2162 unsigned ep_desc_id, idx;
2163 static const char *speed_names[] = { "full", "high", "super" };
2165 if (type != FFS_DESCRIPTOR)
2169 * If ss_descriptors is not NULL, we are reading super speed
2170 * descriptors; if hs_descriptors is not NULL, we are reading high
2171 * speed descriptors; otherwise, we are reading full speed
2174 if (func->function.ss_descriptors) {
2176 func->function.ss_descriptors[(long)valuep] = desc;
2177 } else if (func->function.hs_descriptors) {
2179 func->function.hs_descriptors[(long)valuep] = desc;
2182 func->function.fs_descriptors[(long)valuep] = desc;
2185 if (!desc || desc->bDescriptorType != USB_DT_ENDPOINT)
2188 idx = (ds->bEndpointAddress & USB_ENDPOINT_NUMBER_MASK) - 1;
2189 ffs_ep = func->eps + idx;
2191 if (unlikely(ffs_ep->descs[ep_desc_id])) {
2192 pr_err("two %sspeed descriptors for EP %d\n",
2193 speed_names[ep_desc_id],
2194 ds->bEndpointAddress & USB_ENDPOINT_NUMBER_MASK);
2197 ffs_ep->descs[ep_desc_id] = ds;
2199 ffs_dump_mem(": Original ep desc", ds, ds->bLength);
2201 ds->bEndpointAddress = ffs_ep->descs[0]->bEndpointAddress;
2202 if (!ds->wMaxPacketSize)
2203 ds->wMaxPacketSize = ffs_ep->descs[0]->wMaxPacketSize;
2205 struct usb_request *req;
2208 pr_vdebug("autoconfig\n");
2209 ep = usb_ep_autoconfig(func->gadget, ds);
2212 ep->driver_data = func->eps + idx;
2214 req = usb_ep_alloc_request(ep, GFP_KERNEL);
2220 func->eps_revmap[ds->bEndpointAddress &
2221 USB_ENDPOINT_NUMBER_MASK] = idx + 1;
2223 ffs_dump_mem(": Rewritten ep desc", ds, ds->bLength);
2228 static int __ffs_func_bind_do_nums(enum ffs_entity_type type, u8 *valuep,
2229 struct usb_descriptor_header *desc,
2232 struct ffs_function *func = priv;
2238 case FFS_DESCRIPTOR:
2239 /* Handled in previous pass by __ffs_func_bind_do_descs() */
2244 if (func->interfaces_nums[idx] < 0) {
2245 int id = usb_interface_id(func->conf, &func->function);
2246 if (unlikely(id < 0))
2248 func->interfaces_nums[idx] = id;
2250 newValue = func->interfaces_nums[idx];
2254 /* String' IDs are allocated when fsf_data is bound to cdev */
2255 newValue = func->ffs->stringtabs[0]->strings[*valuep - 1].id;
2260 * USB_DT_ENDPOINT are handled in
2261 * __ffs_func_bind_do_descs().
2263 if (desc->bDescriptorType == USB_DT_ENDPOINT)
2266 idx = (*valuep & USB_ENDPOINT_NUMBER_MASK) - 1;
2267 if (unlikely(!func->eps[idx].ep))
2271 struct usb_endpoint_descriptor **descs;
2272 descs = func->eps[idx].descs;
2273 newValue = descs[descs[0] ? 0 : 1]->bEndpointAddress;
2278 pr_vdebug("%02x -> %02x\n", *valuep, newValue);
2283 static inline struct f_fs_opts *ffs_do_functionfs_bind(struct usb_function *f,
2284 struct usb_configuration *c)
2286 struct ffs_function *func = ffs_func_from_usb(f);
2287 struct f_fs_opts *ffs_opts =
2288 container_of(f->fi, struct f_fs_opts, func_inst);
2294 * Legacy gadget triggers binding in functionfs_ready_callback,
2295 * which already uses locking; taking the same lock here would
2298 * Configfs-enabled gadgets however do need ffs_dev_lock.
2300 if (!ffs_opts->no_configfs)
2302 ret = ffs_opts->dev->desc_ready ? 0 : -ENODEV;
2303 func->ffs = ffs_opts->dev->ffs_data;
2304 if (!ffs_opts->no_configfs)
2307 return ERR_PTR(ret);
2310 func->gadget = c->cdev->gadget;
2312 ffs_data_get(func->ffs);
2315 * in drivers/usb/gadget/configfs.c:configfs_composite_bind()
2316 * configurations are bound in sequence with list_for_each_entry,
2317 * in each configuration its functions are bound in sequence
2318 * with list_for_each_entry, so we assume no race condition
2319 * with regard to ffs_opts->bound access
2321 if (!ffs_opts->refcnt) {
2322 ret = functionfs_bind(func->ffs, c->cdev);
2324 return ERR_PTR(ret);
2327 func->function.strings = func->ffs->stringtabs;
2332 static int _ffs_func_bind(struct usb_configuration *c,
2333 struct usb_function *f)
2335 struct ffs_function *func = ffs_func_from_usb(f);
2336 struct ffs_data *ffs = func->ffs;
2338 const int full = !!func->ffs->fs_descs_count;
2339 const int high = gadget_is_dualspeed(func->gadget) &&
2340 func->ffs->hs_descs_count;
2341 const int super = gadget_is_superspeed(func->gadget) &&
2342 func->ffs->ss_descs_count;
2344 int fs_len, hs_len, ret;
2346 /* Make it a single chunk, less management later on */
2348 vla_item_with_sz(d, struct ffs_ep, eps, ffs->eps_count);
2349 vla_item_with_sz(d, struct usb_descriptor_header *, fs_descs,
2350 full ? ffs->fs_descs_count + 1 : 0);
2351 vla_item_with_sz(d, struct usb_descriptor_header *, hs_descs,
2352 high ? ffs->hs_descs_count + 1 : 0);
2353 vla_item_with_sz(d, struct usb_descriptor_header *, ss_descs,
2354 super ? ffs->ss_descs_count + 1 : 0);
2355 vla_item_with_sz(d, short, inums, ffs->interfaces_count);
2356 vla_item_with_sz(d, char, raw_descs, ffs->raw_descs_length);
2361 /* Has descriptors only for speeds gadget does not support */
2362 if (unlikely(!(full | high | super)))
2365 /* Allocate a single chunk, less management later on */
2366 vlabuf = kmalloc(vla_group_size(d), GFP_KERNEL);
2367 if (unlikely(!vlabuf))
2371 memset(vla_ptr(vlabuf, d, eps), 0, d_eps__sz);
2372 /* Copy descriptors */
2373 memcpy(vla_ptr(vlabuf, d, raw_descs), ffs->raw_descs,
2374 ffs->raw_descs_length);
2376 memset(vla_ptr(vlabuf, d, inums), 0xff, d_inums__sz);
2377 for (ret = ffs->eps_count; ret; --ret) {
2380 ptr = vla_ptr(vlabuf, d, eps);
2385 * d_eps == vlabuf, func->eps used to kfree vlabuf later
2387 func->eps = vla_ptr(vlabuf, d, eps);
2388 func->interfaces_nums = vla_ptr(vlabuf, d, inums);
2391 * Go through all the endpoint descriptors and allocate
2392 * endpoints first, so that later we can rewrite the endpoint
2393 * numbers without worrying that it may be described later on.
2396 func->function.fs_descriptors = vla_ptr(vlabuf, d, fs_descs);
2397 fs_len = ffs_do_descs(ffs->fs_descs_count,
2398 vla_ptr(vlabuf, d, raw_descs),
2400 __ffs_func_bind_do_descs, func);
2401 if (unlikely(fs_len < 0)) {
2410 func->function.hs_descriptors = vla_ptr(vlabuf, d, hs_descs);
2411 hs_len = ffs_do_descs(ffs->hs_descs_count,
2412 vla_ptr(vlabuf, d, raw_descs) + fs_len,
2413 d_raw_descs__sz - fs_len,
2414 __ffs_func_bind_do_descs, func);
2415 if (unlikely(hs_len < 0)) {
2423 if (likely(super)) {
2424 func->function.ss_descriptors = vla_ptr(vlabuf, d, ss_descs);
2425 ret = ffs_do_descs(ffs->ss_descs_count,
2426 vla_ptr(vlabuf, d, raw_descs) + fs_len + hs_len,
2427 d_raw_descs__sz - fs_len - hs_len,
2428 __ffs_func_bind_do_descs, func);
2429 if (unlikely(ret < 0))
2434 * Now handle interface numbers allocation and interface and
2435 * endpoint numbers rewriting. We can do that in one go
2438 ret = ffs_do_descs(ffs->fs_descs_count +
2439 (high ? ffs->hs_descs_count : 0) +
2440 (super ? ffs->ss_descs_count : 0),
2441 vla_ptr(vlabuf, d, raw_descs), d_raw_descs__sz,
2442 __ffs_func_bind_do_nums, func);
2443 if (unlikely(ret < 0))
2446 /* And we're done */
2447 ffs_event_add(ffs, FUNCTIONFS_BIND);
2451 /* XXX Do we need to release all claimed endpoints here? */
2455 static int ffs_func_bind(struct usb_configuration *c,
2456 struct usb_function *f)
2458 struct f_fs_opts *ffs_opts = ffs_do_functionfs_bind(f, c);
2460 if (IS_ERR(ffs_opts))
2461 return PTR_ERR(ffs_opts);
2463 return _ffs_func_bind(c, f);
2467 /* Other USB function hooks *************************************************/
2469 static int ffs_func_set_alt(struct usb_function *f,
2470 unsigned interface, unsigned alt)
2472 struct ffs_function *func = ffs_func_from_usb(f);
2473 struct ffs_data *ffs = func->ffs;
2476 if (alt != (unsigned)-1) {
2477 intf = ffs_func_revmap_intf(func, interface);
2478 if (unlikely(intf < 0))
2483 ffs_func_eps_disable(ffs->func);
2485 if (ffs->state != FFS_ACTIVE)
2488 if (alt == (unsigned)-1) {
2490 ffs_event_add(ffs, FUNCTIONFS_DISABLE);
2495 ret = ffs_func_eps_enable(func);
2496 if (likely(ret >= 0))
2497 ffs_event_add(ffs, FUNCTIONFS_ENABLE);
2501 static void ffs_func_disable(struct usb_function *f)
2503 ffs_func_set_alt(f, 0, (unsigned)-1);
2506 static int ffs_func_setup(struct usb_function *f,
2507 const struct usb_ctrlrequest *creq)
2509 struct ffs_function *func = ffs_func_from_usb(f);
2510 struct ffs_data *ffs = func->ffs;
2511 unsigned long flags;
2516 pr_vdebug("creq->bRequestType = %02x\n", creq->bRequestType);
2517 pr_vdebug("creq->bRequest = %02x\n", creq->bRequest);
2518 pr_vdebug("creq->wValue = %04x\n", le16_to_cpu(creq->wValue));
2519 pr_vdebug("creq->wIndex = %04x\n", le16_to_cpu(creq->wIndex));
2520 pr_vdebug("creq->wLength = %04x\n", le16_to_cpu(creq->wLength));
2523 * Most requests directed to interface go through here
2524 * (notable exceptions are set/get interface) so we need to
2525 * handle them. All other either handled by composite or
2526 * passed to usb_configuration->setup() (if one is set). No
2527 * matter, we will handle requests directed to endpoint here
2528 * as well (as it's straightforward) but what to do with any
2531 if (ffs->state != FFS_ACTIVE)
2534 switch (creq->bRequestType & USB_RECIP_MASK) {
2535 case USB_RECIP_INTERFACE:
2536 ret = ffs_func_revmap_intf(func, le16_to_cpu(creq->wIndex));
2537 if (unlikely(ret < 0))
2541 case USB_RECIP_ENDPOINT:
2542 ret = ffs_func_revmap_ep(func, le16_to_cpu(creq->wIndex));
2543 if (unlikely(ret < 0))
2551 spin_lock_irqsave(&ffs->ev.waitq.lock, flags);
2552 ffs->ev.setup = *creq;
2553 ffs->ev.setup.wIndex = cpu_to_le16(ret);
2554 __ffs_event_add(ffs, FUNCTIONFS_SETUP);
2555 spin_unlock_irqrestore(&ffs->ev.waitq.lock, flags);
2560 static void ffs_func_suspend(struct usb_function *f)
2563 ffs_event_add(ffs_func_from_usb(f)->ffs, FUNCTIONFS_SUSPEND);
2566 static void ffs_func_resume(struct usb_function *f)
2569 ffs_event_add(ffs_func_from_usb(f)->ffs, FUNCTIONFS_RESUME);
2573 /* Endpoint and interface numbers reverse mapping ***************************/
2575 static int ffs_func_revmap_ep(struct ffs_function *func, u8 num)
2577 num = func->eps_revmap[num & USB_ENDPOINT_NUMBER_MASK];
2578 return num ? num : -EDOM;
2581 static int ffs_func_revmap_intf(struct ffs_function *func, u8 intf)
2583 short *nums = func->interfaces_nums;
2584 unsigned count = func->ffs->interfaces_count;
2586 for (; count; --count, ++nums) {
2587 if (*nums >= 0 && *nums == intf)
2588 return nums - func->interfaces_nums;
2595 /* Devices management *******************************************************/
2597 static LIST_HEAD(ffs_devices);
2599 static struct ffs_dev *_ffs_do_find_dev(const char *name)
2601 struct ffs_dev *dev;
2603 list_for_each_entry(dev, &ffs_devices, entry) {
2604 if (!dev->name || !name)
2606 if (strcmp(dev->name, name) == 0)
2614 * ffs_lock must be taken by the caller of this function
2616 static struct ffs_dev *_ffs_get_single_dev(void)
2618 struct ffs_dev *dev;
2620 if (list_is_singular(&ffs_devices)) {
2621 dev = list_first_entry(&ffs_devices, struct ffs_dev, entry);
2630 * ffs_lock must be taken by the caller of this function
2632 static struct ffs_dev *_ffs_find_dev(const char *name)
2634 struct ffs_dev *dev;
2636 dev = _ffs_get_single_dev();
2640 return _ffs_do_find_dev(name);
2643 /* Configfs support *********************************************************/
2645 static inline struct f_fs_opts *to_ffs_opts(struct config_item *item)
2647 return container_of(to_config_group(item), struct f_fs_opts,
2651 static void ffs_attr_release(struct config_item *item)
2653 struct f_fs_opts *opts = to_ffs_opts(item);
2655 usb_put_function_instance(&opts->func_inst);
2658 static struct configfs_item_operations ffs_item_ops = {
2659 .release = ffs_attr_release,
2662 static struct config_item_type ffs_func_type = {
2663 .ct_item_ops = &ffs_item_ops,
2664 .ct_owner = THIS_MODULE,
2668 /* Function registration interface ******************************************/
2670 static void ffs_free_inst(struct usb_function_instance *f)
2672 struct f_fs_opts *opts;
2674 opts = to_f_fs_opts(f);
2676 _ffs_free_dev(opts->dev);
2681 #define MAX_INST_NAME_LEN 40
2683 static int ffs_set_inst_name(struct usb_function_instance *fi, const char *name)
2685 struct f_fs_opts *opts;
2690 name_len = strlen(name) + 1;
2691 if (name_len > MAX_INST_NAME_LEN)
2692 return -ENAMETOOLONG;
2694 ptr = kstrndup(name, name_len, GFP_KERNEL);
2698 opts = to_f_fs_opts(fi);
2703 tmp = opts->dev->name_allocated ? opts->dev->name : NULL;
2704 ret = _ffs_name_dev(opts->dev, ptr);
2710 opts->dev->name_allocated = true;
2719 static struct usb_function_instance *ffs_alloc_inst(void)
2721 struct f_fs_opts *opts;
2722 struct ffs_dev *dev;
2724 opts = kzalloc(sizeof(*opts), GFP_KERNEL);
2726 return ERR_PTR(-ENOMEM);
2728 opts->func_inst.set_inst_name = ffs_set_inst_name;
2729 opts->func_inst.free_func_inst = ffs_free_inst;
2731 dev = _ffs_alloc_dev();
2735 return ERR_CAST(dev);
2740 config_group_init_type_name(&opts->func_inst.group, "",
2742 return &opts->func_inst;
2745 static void ffs_free(struct usb_function *f)
2747 kfree(ffs_func_from_usb(f));
2750 static void ffs_func_unbind(struct usb_configuration *c,
2751 struct usb_function *f)
2753 struct ffs_function *func = ffs_func_from_usb(f);
2754 struct ffs_data *ffs = func->ffs;
2755 struct f_fs_opts *opts =
2756 container_of(f->fi, struct f_fs_opts, func_inst);
2757 struct ffs_ep *ep = func->eps;
2758 unsigned count = ffs->eps_count;
2759 unsigned long flags;
2762 if (ffs->func == func) {
2763 ffs_func_eps_disable(func);
2767 if (!--opts->refcnt)
2768 functionfs_unbind(ffs);
2770 /* cleanup after autoconfig */
2771 spin_lock_irqsave(&func->ffs->eps_lock, flags);
2773 if (ep->ep && ep->req)
2774 usb_ep_free_request(ep->ep, ep->req);
2778 spin_unlock_irqrestore(&func->ffs->eps_lock, flags);
2782 * eps, descriptors and interfaces_nums are allocated in the
2783 * same chunk so only one free is required.
2785 func->function.fs_descriptors = NULL;
2786 func->function.hs_descriptors = NULL;
2787 func->function.ss_descriptors = NULL;
2788 func->interfaces_nums = NULL;
2790 ffs_event_add(ffs, FUNCTIONFS_UNBIND);
2793 static struct usb_function *ffs_alloc(struct usb_function_instance *fi)
2795 struct ffs_function *func;
2799 func = kzalloc(sizeof(*func), GFP_KERNEL);
2800 if (unlikely(!func))
2801 return ERR_PTR(-ENOMEM);
2803 func->function.name = "Function FS Gadget";
2805 func->function.bind = ffs_func_bind;
2806 func->function.unbind = ffs_func_unbind;
2807 func->function.set_alt = ffs_func_set_alt;
2808 func->function.disable = ffs_func_disable;
2809 func->function.setup = ffs_func_setup;
2810 func->function.suspend = ffs_func_suspend;
2811 func->function.resume = ffs_func_resume;
2812 func->function.free_func = ffs_free;
2814 return &func->function;
2818 * ffs_lock must be taken by the caller of this function
2820 static struct ffs_dev *_ffs_alloc_dev(void)
2822 struct ffs_dev *dev;
2825 if (_ffs_get_single_dev())
2826 return ERR_PTR(-EBUSY);
2828 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
2830 return ERR_PTR(-ENOMEM);
2832 if (list_empty(&ffs_devices)) {
2833 ret = functionfs_init();
2836 return ERR_PTR(ret);
2840 list_add(&dev->entry, &ffs_devices);
2846 * ffs_lock must be taken by the caller of this function
2847 * The caller is responsible for "name" being available whenever f_fs needs it
2849 static int _ffs_name_dev(struct ffs_dev *dev, const char *name)
2851 struct ffs_dev *existing;
2853 existing = _ffs_do_find_dev(name);
2863 * The caller is responsible for "name" being available whenever f_fs needs it
2865 int ffs_name_dev(struct ffs_dev *dev, const char *name)
2870 ret = _ffs_name_dev(dev, name);
2875 EXPORT_SYMBOL(ffs_name_dev);
2877 int ffs_single_dev(struct ffs_dev *dev)
2884 if (!list_is_singular(&ffs_devices))
2892 EXPORT_SYMBOL(ffs_single_dev);
2895 * ffs_lock must be taken by the caller of this function
2897 static void _ffs_free_dev(struct ffs_dev *dev)
2899 list_del(&dev->entry);
2900 if (dev->name_allocated)
2903 if (list_empty(&ffs_devices))
2904 functionfs_cleanup();
2907 static void *ffs_acquire_dev(const char *dev_name)
2909 struct ffs_dev *ffs_dev;
2914 ffs_dev = _ffs_find_dev(dev_name);
2916 ffs_dev = ERR_PTR(-ENODEV);
2917 else if (ffs_dev->mounted)
2918 ffs_dev = ERR_PTR(-EBUSY);
2919 else if (ffs_dev->ffs_acquire_dev_callback &&
2920 ffs_dev->ffs_acquire_dev_callback(ffs_dev))
2921 ffs_dev = ERR_PTR(-ENODEV);
2923 ffs_dev->mounted = true;
2929 static void ffs_release_dev(struct ffs_data *ffs_data)
2931 struct ffs_dev *ffs_dev;
2936 ffs_dev = ffs_data->private_data;
2938 ffs_dev->mounted = false;
2940 if (ffs_dev->ffs_release_dev_callback)
2941 ffs_dev->ffs_release_dev_callback(ffs_dev);
2947 static int ffs_ready(struct ffs_data *ffs)
2949 struct ffs_dev *ffs_obj;
2955 ffs_obj = ffs->private_data;
2960 if (WARN_ON(ffs_obj->desc_ready)) {
2965 ffs_obj->desc_ready = true;
2966 ffs_obj->ffs_data = ffs;
2968 if (ffs_obj->ffs_ready_callback)
2969 ret = ffs_obj->ffs_ready_callback(ffs);
2976 static void ffs_closed(struct ffs_data *ffs)
2978 struct ffs_dev *ffs_obj;
2983 ffs_obj = ffs->private_data;
2987 ffs_obj->desc_ready = false;
2989 if (ffs_obj->ffs_closed_callback)
2990 ffs_obj->ffs_closed_callback(ffs);
2992 if (!ffs_obj->opts || ffs_obj->opts->no_configfs
2993 || !ffs_obj->opts->func_inst.group.cg_item.ci_parent)
2996 unregister_gadget_item(ffs_obj->opts->
2997 func_inst.group.cg_item.ci_parent->ci_parent);
3002 /* Misc helper functions ****************************************************/
3004 static int ffs_mutex_lock(struct mutex *mutex, unsigned nonblock)
3007 ? likely(mutex_trylock(mutex)) ? 0 : -EAGAIN
3008 : mutex_lock_interruptible(mutex);
3011 static char *ffs_prepare_buffer(const char __user *buf, size_t len)
3018 data = kmalloc(len, GFP_KERNEL);
3019 if (unlikely(!data))
3020 return ERR_PTR(-ENOMEM);
3022 if (unlikely(__copy_from_user(data, buf, len))) {
3024 return ERR_PTR(-EFAULT);
3027 pr_vdebug("Buffer from user space:\n");
3028 ffs_dump_mem("", data, len);
3033 DECLARE_USB_FUNCTION_INIT(ffs, ffs_alloc_inst, ffs_alloc);
3034 MODULE_LICENSE("GPL");
3035 MODULE_AUTHOR("Michal Nazarewicz");