1 // SPDX-License-Identifier: GPL-2.0+
3 * f_fs.c -- user mode file system API for USB composite function controllers
5 * Copyright (C) 2010 Samsung Electronics
6 * Author: Michal Nazarewicz <mina86@mina86.com>
8 * Based on inode.c (GadgetFS) which was:
9 * Copyright (C) 2003-2004 David Brownell
10 * Copyright (C) 2003 Agilent Technologies
15 /* #define VERBOSE_DEBUG */
17 #include <linux/blkdev.h>
18 #include <linux/pagemap.h>
19 #include <linux/export.h>
20 #include <linux/hid.h>
21 #include <linux/module.h>
22 #include <linux/sched/signal.h>
23 #include <linux/uio.h>
24 #include <asm/unaligned.h>
26 #include <linux/usb/composite.h>
27 #include <linux/usb/functionfs.h>
29 #include <linux/aio.h>
30 #include <linux/mmu_context.h>
31 #include <linux/poll.h>
32 #include <linux/eventfd.h>
36 #include "u_os_desc.h"
39 #define FUNCTIONFS_MAGIC 0xa647361 /* Chosen by a honest dice roll ;) */
41 /* Reference counter handling */
42 static void ffs_data_get(struct ffs_data
*ffs
);
43 static void ffs_data_put(struct ffs_data
*ffs
);
44 /* Creates new ffs_data object. */
45 static struct ffs_data
*__must_check
ffs_data_new(const char *dev_name
)
46 __attribute__((malloc
));
48 /* Opened counter handling. */
49 static void ffs_data_opened(struct ffs_data
*ffs
);
50 static void ffs_data_closed(struct ffs_data
*ffs
);
52 /* Called with ffs->mutex held; take over ownership of data. */
53 static int __must_check
54 __ffs_data_got_descs(struct ffs_data
*ffs
, char *data
, size_t len
);
55 static int __must_check
56 __ffs_data_got_strings(struct ffs_data
*ffs
, char *data
, size_t len
);
59 /* The function structure ***************************************************/
64 struct usb_configuration
*conf
;
65 struct usb_gadget
*gadget
;
70 short *interfaces_nums
;
72 struct usb_function function
;
76 static struct ffs_function
*ffs_func_from_usb(struct usb_function
*f
)
78 return container_of(f
, struct ffs_function
, function
);
82 static inline enum ffs_setup_state
83 ffs_setup_state_clear_cancelled(struct ffs_data
*ffs
)
85 return (enum ffs_setup_state
)
86 cmpxchg(&ffs
->setup_state
, FFS_SETUP_CANCELLED
, FFS_NO_SETUP
);
90 static void ffs_func_eps_disable(struct ffs_function
*func
);
91 static int __must_check
ffs_func_eps_enable(struct ffs_function
*func
);
93 static int ffs_func_bind(struct usb_configuration
*,
94 struct usb_function
*);
95 static int ffs_func_set_alt(struct usb_function
*, unsigned, unsigned);
96 static void ffs_func_disable(struct usb_function
*);
97 static int ffs_func_setup(struct usb_function
*,
98 const struct usb_ctrlrequest
*);
99 static bool ffs_func_req_match(struct usb_function
*,
100 const struct usb_ctrlrequest
*,
102 static void ffs_func_suspend(struct usb_function
*);
103 static void ffs_func_resume(struct usb_function
*);
106 static int ffs_func_revmap_ep(struct ffs_function
*func
, u8 num
);
107 static int ffs_func_revmap_intf(struct ffs_function
*func
, u8 intf
);
110 /* The endpoints structures *************************************************/
113 struct usb_ep
*ep
; /* P: ffs->eps_lock */
114 struct usb_request
*req
; /* P: epfile->mutex */
116 /* [0]: full speed, [1]: high speed, [2]: super speed */
117 struct usb_endpoint_descriptor
*descs
[3];
121 int status
; /* P: epfile->mutex */
125 /* Protects ep->ep and ep->req. */
128 struct ffs_data
*ffs
;
129 struct ffs_ep
*ep
; /* P: ffs->eps_lock */
131 struct dentry
*dentry
;
134 * Buffer for holding data from partial reads which may happen since
135 * we’re rounding user read requests to a multiple of a max packet size.
137 * The pointer is initialised with NULL value and may be set by
138 * __ffs_epfile_read_data function to point to a temporary buffer.
140 * In normal operation, calls to __ffs_epfile_read_buffered will consume
141 * data from said buffer and eventually free it. Importantly, while the
142 * function is using the buffer, it sets the pointer to NULL. This is
143 * all right since __ffs_epfile_read_data and __ffs_epfile_read_buffered
144 * can never run concurrently (they are synchronised by epfile->mutex)
145 * so the latter will not assign a new value to the pointer.
147 * Meanwhile ffs_func_eps_disable frees the buffer (if the pointer is
148 * valid) and sets the pointer to READ_BUFFER_DROP value. This special
149 * value is crux of the synchronisation between ffs_func_eps_disable and
150 * __ffs_epfile_read_data.
152 * Once __ffs_epfile_read_data is about to finish it will try to set the
153 * pointer back to its old value (as described above), but seeing as the
154 * pointer is not-NULL (namely READ_BUFFER_DROP) it will instead free
157 * == State transitions ==
159 * • ptr == NULL: (initial state)
160 * ◦ __ffs_epfile_read_buffer_free: go to ptr == DROP
161 * ◦ __ffs_epfile_read_buffered: nop
162 * ◦ __ffs_epfile_read_data allocates temp buffer: go to ptr == buf
163 * ◦ reading finishes: n/a, not in ‘and reading’ state
165 * ◦ __ffs_epfile_read_buffer_free: nop
166 * ◦ __ffs_epfile_read_buffered: go to ptr == NULL
167 * ◦ __ffs_epfile_read_data allocates temp buffer: free buf, nop
168 * ◦ reading finishes: n/a, not in ‘and reading’ state
170 * ◦ __ffs_epfile_read_buffer_free: free buf, go to ptr == DROP
171 * ◦ __ffs_epfile_read_buffered: go to ptr == NULL and reading
172 * ◦ __ffs_epfile_read_data: n/a, __ffs_epfile_read_buffered
173 * is always called first
174 * ◦ reading finishes: n/a, not in ‘and reading’ state
175 * • ptr == NULL and reading:
176 * ◦ __ffs_epfile_read_buffer_free: go to ptr == DROP and reading
177 * ◦ __ffs_epfile_read_buffered: n/a, mutex is held
178 * ◦ __ffs_epfile_read_data: n/a, mutex is held
179 * ◦ reading finishes and …
180 * … all data read: free buf, go to ptr == NULL
181 * … otherwise: go to ptr == buf and reading
182 * • ptr == DROP and reading:
183 * ◦ __ffs_epfile_read_buffer_free: nop
184 * ◦ __ffs_epfile_read_buffered: n/a, mutex is held
185 * ◦ __ffs_epfile_read_data: n/a, mutex is held
186 * ◦ reading finishes: free buf, go to ptr == DROP
188 struct ffs_buffer
*read_buffer
;
189 #define READ_BUFFER_DROP ((struct ffs_buffer *)ERR_PTR(-ESHUTDOWN))
193 unsigned char in
; /* P: ffs->eps_lock */
194 unsigned char isoc
; /* P: ffs->eps_lock */
205 /* ffs_io_data structure ***************************************************/
212 struct iov_iter data
;
216 struct mm_struct
*mm
;
217 struct work_struct work
;
220 struct usb_request
*req
;
222 struct ffs_data
*ffs
;
225 struct ffs_desc_helper
{
226 struct ffs_data
*ffs
;
227 unsigned interfaces_count
;
231 static int __must_check
ffs_epfiles_create(struct ffs_data
*ffs
);
232 static void ffs_epfiles_destroy(struct ffs_epfile
*epfiles
, unsigned count
);
234 static struct dentry
*
235 ffs_sb_create_file(struct super_block
*sb
, const char *name
, void *data
,
236 const struct file_operations
*fops
);
238 /* Devices management *******************************************************/
240 DEFINE_MUTEX(ffs_lock
);
241 EXPORT_SYMBOL_GPL(ffs_lock
);
243 static struct ffs_dev
*_ffs_find_dev(const char *name
);
244 static struct ffs_dev
*_ffs_alloc_dev(void);
245 static void _ffs_free_dev(struct ffs_dev
*dev
);
246 static void *ffs_acquire_dev(const char *dev_name
);
247 static void ffs_release_dev(struct ffs_data
*ffs_data
);
248 static int ffs_ready(struct ffs_data
*ffs
);
249 static void ffs_closed(struct ffs_data
*ffs
);
251 /* Misc helper functions ****************************************************/
253 static int ffs_mutex_lock(struct mutex
*mutex
, unsigned nonblock
)
254 __attribute__((warn_unused_result
, nonnull
));
255 static char *ffs_prepare_buffer(const char __user
*buf
, size_t len
)
256 __attribute__((warn_unused_result
, nonnull
));
259 /* Control file aka ep0 *****************************************************/
261 static void ffs_ep0_complete(struct usb_ep
*ep
, struct usb_request
*req
)
263 struct ffs_data
*ffs
= req
->context
;
265 complete(&ffs
->ep0req_completion
);
268 static int __ffs_ep0_queue_wait(struct ffs_data
*ffs
, char *data
, size_t len
)
270 struct usb_request
*req
= ffs
->ep0req
;
273 req
->zero
= len
< le16_to_cpu(ffs
->ev
.setup
.wLength
);
275 spin_unlock_irq(&ffs
->ev
.waitq
.lock
);
281 * UDC layer requires to provide a buffer even for ZLP, but should
282 * not use it at all. Let's provide some poisoned pointer to catch
283 * possible bug in the driver.
285 if (req
->buf
== NULL
)
286 req
->buf
= (void *)0xDEADBABE;
288 reinit_completion(&ffs
->ep0req_completion
);
290 ret
= usb_ep_queue(ffs
->gadget
->ep0
, req
, GFP_ATOMIC
);
291 if (unlikely(ret
< 0))
294 ret
= wait_for_completion_interruptible(&ffs
->ep0req_completion
);
296 usb_ep_dequeue(ffs
->gadget
->ep0
, req
);
300 ffs
->setup_state
= FFS_NO_SETUP
;
301 return req
->status
? req
->status
: req
->actual
;
304 static int __ffs_ep0_stall(struct ffs_data
*ffs
)
306 if (ffs
->ev
.can_stall
) {
307 pr_vdebug("ep0 stall\n");
308 usb_ep_set_halt(ffs
->gadget
->ep0
);
309 ffs
->setup_state
= FFS_NO_SETUP
;
312 pr_debug("bogus ep0 stall!\n");
317 static ssize_t
ffs_ep0_write(struct file
*file
, const char __user
*buf
,
318 size_t len
, loff_t
*ptr
)
320 struct ffs_data
*ffs
= file
->private_data
;
326 /* Fast check if setup was canceled */
327 if (ffs_setup_state_clear_cancelled(ffs
) == FFS_SETUP_CANCELLED
)
331 ret
= ffs_mutex_lock(&ffs
->mutex
, file
->f_flags
& O_NONBLOCK
);
332 if (unlikely(ret
< 0))
336 switch (ffs
->state
) {
337 case FFS_READ_DESCRIPTORS
:
338 case FFS_READ_STRINGS
:
340 if (unlikely(len
< 16)) {
345 data
= ffs_prepare_buffer(buf
, len
);
352 if (ffs
->state
== FFS_READ_DESCRIPTORS
) {
353 pr_info("read descriptors\n");
354 ret
= __ffs_data_got_descs(ffs
, data
, len
);
355 if (unlikely(ret
< 0))
358 ffs
->state
= FFS_READ_STRINGS
;
361 pr_info("read strings\n");
362 ret
= __ffs_data_got_strings(ffs
, data
, len
);
363 if (unlikely(ret
< 0))
366 ret
= ffs_epfiles_create(ffs
);
368 ffs
->state
= FFS_CLOSING
;
372 ffs
->state
= FFS_ACTIVE
;
373 mutex_unlock(&ffs
->mutex
);
375 ret
= ffs_ready(ffs
);
376 if (unlikely(ret
< 0)) {
377 ffs
->state
= FFS_CLOSING
;
388 * We're called from user space, we can use _irq
389 * rather then _irqsave
391 spin_lock_irq(&ffs
->ev
.waitq
.lock
);
392 switch (ffs_setup_state_clear_cancelled(ffs
)) {
393 case FFS_SETUP_CANCELLED
:
401 case FFS_SETUP_PENDING
:
405 /* FFS_SETUP_PENDING */
406 if (!(ffs
->ev
.setup
.bRequestType
& USB_DIR_IN
)) {
407 spin_unlock_irq(&ffs
->ev
.waitq
.lock
);
408 ret
= __ffs_ep0_stall(ffs
);
412 /* FFS_SETUP_PENDING and not stall */
413 len
= min(len
, (size_t)le16_to_cpu(ffs
->ev
.setup
.wLength
));
415 spin_unlock_irq(&ffs
->ev
.waitq
.lock
);
417 data
= ffs_prepare_buffer(buf
, len
);
423 spin_lock_irq(&ffs
->ev
.waitq
.lock
);
426 * We are guaranteed to be still in FFS_ACTIVE state
427 * but the state of setup could have changed from
428 * FFS_SETUP_PENDING to FFS_SETUP_CANCELLED so we need
429 * to check for that. If that happened we copied data
430 * from user space in vain but it's unlikely.
432 * For sure we are not in FFS_NO_SETUP since this is
433 * the only place FFS_SETUP_PENDING -> FFS_NO_SETUP
434 * transition can be performed and it's protected by
437 if (ffs_setup_state_clear_cancelled(ffs
) ==
438 FFS_SETUP_CANCELLED
) {
441 spin_unlock_irq(&ffs
->ev
.waitq
.lock
);
443 /* unlocks spinlock */
444 ret
= __ffs_ep0_queue_wait(ffs
, data
, len
);
454 mutex_unlock(&ffs
->mutex
);
458 /* Called with ffs->ev.waitq.lock and ffs->mutex held, both released on exit. */
459 static ssize_t
__ffs_ep0_read_events(struct ffs_data
*ffs
, char __user
*buf
,
463 * n cannot be bigger than ffs->ev.count, which cannot be bigger than
464 * size of ffs->ev.types array (which is four) so that's how much space
467 struct usb_functionfs_event events
[ARRAY_SIZE(ffs
->ev
.types
)];
468 const size_t size
= n
* sizeof *events
;
471 memset(events
, 0, size
);
474 events
[i
].type
= ffs
->ev
.types
[i
];
475 if (events
[i
].type
== FUNCTIONFS_SETUP
) {
476 events
[i
].u
.setup
= ffs
->ev
.setup
;
477 ffs
->setup_state
= FFS_SETUP_PENDING
;
483 memmove(ffs
->ev
.types
, ffs
->ev
.types
+ n
,
484 ffs
->ev
.count
* sizeof *ffs
->ev
.types
);
486 spin_unlock_irq(&ffs
->ev
.waitq
.lock
);
487 mutex_unlock(&ffs
->mutex
);
489 return unlikely(copy_to_user(buf
, events
, size
)) ? -EFAULT
: size
;
492 static ssize_t
ffs_ep0_read(struct file
*file
, char __user
*buf
,
493 size_t len
, loff_t
*ptr
)
495 struct ffs_data
*ffs
= file
->private_data
;
502 /* Fast check if setup was canceled */
503 if (ffs_setup_state_clear_cancelled(ffs
) == FFS_SETUP_CANCELLED
)
507 ret
= ffs_mutex_lock(&ffs
->mutex
, file
->f_flags
& O_NONBLOCK
);
508 if (unlikely(ret
< 0))
512 if (ffs
->state
!= FFS_ACTIVE
) {
518 * We're called from user space, we can use _irq rather then
521 spin_lock_irq(&ffs
->ev
.waitq
.lock
);
523 switch (ffs_setup_state_clear_cancelled(ffs
)) {
524 case FFS_SETUP_CANCELLED
:
529 n
= len
/ sizeof(struct usb_functionfs_event
);
535 if ((file
->f_flags
& O_NONBLOCK
) && !ffs
->ev
.count
) {
540 if (wait_event_interruptible_exclusive_locked_irq(ffs
->ev
.waitq
,
546 return __ffs_ep0_read_events(ffs
, buf
,
547 min(n
, (size_t)ffs
->ev
.count
));
549 case FFS_SETUP_PENDING
:
550 if (ffs
->ev
.setup
.bRequestType
& USB_DIR_IN
) {
551 spin_unlock_irq(&ffs
->ev
.waitq
.lock
);
552 ret
= __ffs_ep0_stall(ffs
);
556 len
= min(len
, (size_t)le16_to_cpu(ffs
->ev
.setup
.wLength
));
558 spin_unlock_irq(&ffs
->ev
.waitq
.lock
);
561 data
= kmalloc(len
, GFP_KERNEL
);
562 if (unlikely(!data
)) {
568 spin_lock_irq(&ffs
->ev
.waitq
.lock
);
570 /* See ffs_ep0_write() */
571 if (ffs_setup_state_clear_cancelled(ffs
) ==
572 FFS_SETUP_CANCELLED
) {
577 /* unlocks spinlock */
578 ret
= __ffs_ep0_queue_wait(ffs
, data
, len
);
579 if (likely(ret
> 0) && unlikely(copy_to_user(buf
, data
, len
)))
588 spin_unlock_irq(&ffs
->ev
.waitq
.lock
);
590 mutex_unlock(&ffs
->mutex
);
595 static int ffs_ep0_open(struct inode
*inode
, struct file
*file
)
597 struct ffs_data
*ffs
= inode
->i_private
;
601 if (unlikely(ffs
->state
== FFS_CLOSING
))
604 file
->private_data
= ffs
;
605 ffs_data_opened(ffs
);
610 static int ffs_ep0_release(struct inode
*inode
, struct file
*file
)
612 struct ffs_data
*ffs
= file
->private_data
;
616 ffs_data_closed(ffs
);
621 static long ffs_ep0_ioctl(struct file
*file
, unsigned code
, unsigned long value
)
623 struct ffs_data
*ffs
= file
->private_data
;
624 struct usb_gadget
*gadget
= ffs
->gadget
;
629 if (code
== FUNCTIONFS_INTERFACE_REVMAP
) {
630 struct ffs_function
*func
= ffs
->func
;
631 ret
= func
? ffs_func_revmap_intf(func
, value
) : -ENODEV
;
632 } else if (gadget
&& gadget
->ops
->ioctl
) {
633 ret
= gadget
->ops
->ioctl(gadget
, code
, value
);
641 static unsigned int ffs_ep0_poll(struct file
*file
, poll_table
*wait
)
643 struct ffs_data
*ffs
= file
->private_data
;
644 unsigned int mask
= POLLWRNORM
;
647 poll_wait(file
, &ffs
->ev
.waitq
, wait
);
649 ret
= ffs_mutex_lock(&ffs
->mutex
, file
->f_flags
& O_NONBLOCK
);
650 if (unlikely(ret
< 0))
653 switch (ffs
->state
) {
654 case FFS_READ_DESCRIPTORS
:
655 case FFS_READ_STRINGS
:
660 switch (ffs
->setup_state
) {
666 case FFS_SETUP_PENDING
:
667 case FFS_SETUP_CANCELLED
:
668 mask
|= (POLLIN
| POLLOUT
);
673 case FFS_DEACTIVATED
:
677 mutex_unlock(&ffs
->mutex
);
682 static const struct file_operations ffs_ep0_operations
= {
685 .open
= ffs_ep0_open
,
686 .write
= ffs_ep0_write
,
687 .read
= ffs_ep0_read
,
688 .release
= ffs_ep0_release
,
689 .unlocked_ioctl
= ffs_ep0_ioctl
,
690 .poll
= ffs_ep0_poll
,
694 /* "Normal" endpoints operations ********************************************/
696 static void ffs_epfile_io_complete(struct usb_ep
*_ep
, struct usb_request
*req
)
699 if (likely(req
->context
)) {
700 struct ffs_ep
*ep
= _ep
->driver_data
;
701 ep
->status
= req
->status
? req
->status
: req
->actual
;
702 complete(req
->context
);
706 static ssize_t
ffs_copy_to_iter(void *data
, int data_len
, struct iov_iter
*iter
)
708 ssize_t ret
= copy_to_iter(data
, data_len
, iter
);
709 if (likely(ret
== data_len
))
712 if (unlikely(iov_iter_count(iter
)))
716 * Dear user space developer!
718 * TL;DR: To stop getting below error message in your kernel log, change
719 * user space code using functionfs to align read buffers to a max
722 * Some UDCs (e.g. dwc3) require request sizes to be a multiple of a max
723 * packet size. When unaligned buffer is passed to functionfs, it
724 * internally uses a larger, aligned buffer so that such UDCs are happy.
726 * Unfortunately, this means that host may send more data than was
727 * requested in read(2) system call. f_fs doesn’t know what to do with
728 * that excess data so it simply drops it.
730 * Was the buffer aligned in the first place, no such problem would
733 * Data may be dropped only in AIO reads. Synchronous reads are handled
734 * by splitting a request into multiple parts. This splitting may still
735 * be a problem though so it’s likely best to align the buffer
736 * regardless of it being AIO or not..
738 * This only affects OUT endpoints, i.e. reading data with a read(2),
739 * aio_read(2) etc. system calls. Writing data to an IN endpoint is not
742 pr_err("functionfs read size %d > requested size %zd, dropping excess data. "
743 "Align read buffer size to max packet size to avoid the problem.\n",
749 static void ffs_user_copy_worker(struct work_struct
*work
)
751 struct ffs_io_data
*io_data
= container_of(work
, struct ffs_io_data
,
753 int ret
= io_data
->req
->status
? io_data
->req
->status
:
754 io_data
->req
->actual
;
755 bool kiocb_has_eventfd
= io_data
->kiocb
->ki_flags
& IOCB_EVENTFD
;
757 if (io_data
->read
&& ret
> 0) {
759 ret
= ffs_copy_to_iter(io_data
->buf
, ret
, &io_data
->data
);
760 unuse_mm(io_data
->mm
);
763 io_data
->kiocb
->ki_complete(io_data
->kiocb
, ret
, ret
);
765 if (io_data
->ffs
->ffs_eventfd
&& !kiocb_has_eventfd
)
766 eventfd_signal(io_data
->ffs
->ffs_eventfd
, 1);
768 usb_ep_free_request(io_data
->ep
, io_data
->req
);
771 kfree(io_data
->to_free
);
776 static void ffs_epfile_async_io_complete(struct usb_ep
*_ep
,
777 struct usb_request
*req
)
779 struct ffs_io_data
*io_data
= req
->context
;
780 struct ffs_data
*ffs
= io_data
->ffs
;
784 INIT_WORK(&io_data
->work
, ffs_user_copy_worker
);
785 queue_work(ffs
->io_completion_wq
, &io_data
->work
);
788 static void __ffs_epfile_read_buffer_free(struct ffs_epfile
*epfile
)
791 * See comment in struct ffs_epfile for full read_buffer pointer
792 * synchronisation story.
794 struct ffs_buffer
*buf
= xchg(&epfile
->read_buffer
, READ_BUFFER_DROP
);
795 if (buf
&& buf
!= READ_BUFFER_DROP
)
799 /* Assumes epfile->mutex is held. */
800 static ssize_t
__ffs_epfile_read_buffered(struct ffs_epfile
*epfile
,
801 struct iov_iter
*iter
)
804 * Null out epfile->read_buffer so ffs_func_eps_disable does not free
805 * the buffer while we are using it. See comment in struct ffs_epfile
806 * for full read_buffer pointer synchronisation story.
808 struct ffs_buffer
*buf
= xchg(&epfile
->read_buffer
, NULL
);
810 if (!buf
|| buf
== READ_BUFFER_DROP
)
813 ret
= copy_to_iter(buf
->data
, buf
->length
, iter
);
814 if (buf
->length
== ret
) {
819 if (unlikely(iov_iter_count(iter
))) {
826 if (cmpxchg(&epfile
->read_buffer
, NULL
, buf
))
832 /* Assumes epfile->mutex is held. */
833 static ssize_t
__ffs_epfile_read_data(struct ffs_epfile
*epfile
,
834 void *data
, int data_len
,
835 struct iov_iter
*iter
)
837 struct ffs_buffer
*buf
;
839 ssize_t ret
= copy_to_iter(data
, data_len
, iter
);
840 if (likely(data_len
== ret
))
843 if (unlikely(iov_iter_count(iter
)))
846 /* See ffs_copy_to_iter for more context. */
847 pr_warn("functionfs read size %d > requested size %zd, splitting request into multiple reads.",
851 buf
= kmalloc(sizeof(*buf
) + data_len
, GFP_KERNEL
);
854 buf
->length
= data_len
;
855 buf
->data
= buf
->storage
;
856 memcpy(buf
->storage
, data
+ ret
, data_len
);
859 * At this point read_buffer is NULL or READ_BUFFER_DROP (if
860 * ffs_func_eps_disable has been called in the meanwhile). See comment
861 * in struct ffs_epfile for full read_buffer pointer synchronisation
864 if (unlikely(cmpxchg(&epfile
->read_buffer
, NULL
, buf
)))
870 static ssize_t
ffs_epfile_io(struct file
*file
, struct ffs_io_data
*io_data
)
872 struct ffs_epfile
*epfile
= file
->private_data
;
873 struct usb_request
*req
;
876 ssize_t ret
, data_len
= -EINVAL
;
879 /* Are we still active? */
880 if (WARN_ON(epfile
->ffs
->state
!= FFS_ACTIVE
))
883 /* Wait for endpoint to be enabled */
886 if (file
->f_flags
& O_NONBLOCK
)
889 ret
= wait_event_interruptible(
890 epfile
->ffs
->wait
, (ep
= epfile
->ep
));
896 halt
= (!io_data
->read
== !epfile
->in
);
897 if (halt
&& epfile
->isoc
)
900 /* We will be using request and read_buffer */
901 ret
= ffs_mutex_lock(&epfile
->mutex
, file
->f_flags
& O_NONBLOCK
);
905 /* Allocate & copy */
907 struct usb_gadget
*gadget
;
910 * Do we have buffered data from previous partial read? Check
911 * that for synchronous case only because we do not have
912 * facility to ‘wake up’ a pending asynchronous read and push
913 * buffered data to it which we would need to make things behave
916 if (!io_data
->aio
&& io_data
->read
) {
917 ret
= __ffs_epfile_read_buffered(epfile
, &io_data
->data
);
923 * if we _do_ wait above, the epfile->ffs->gadget might be NULL
924 * before the waiting completes, so do not assign to 'gadget'
927 gadget
= epfile
->ffs
->gadget
;
929 spin_lock_irq(&epfile
->ffs
->eps_lock
);
930 /* In the meantime, endpoint got disabled or changed. */
931 if (epfile
->ep
!= ep
) {
935 data_len
= iov_iter_count(&io_data
->data
);
937 * Controller may require buffer size to be aligned to
938 * maxpacketsize of an out endpoint.
941 data_len
= usb_ep_align_maybe(gadget
, ep
->ep
, data_len
);
942 spin_unlock_irq(&epfile
->ffs
->eps_lock
);
944 data
= kmalloc(data_len
, GFP_KERNEL
);
945 if (unlikely(!data
)) {
949 if (!io_data
->read
&&
950 !copy_from_iter_full(data
, data_len
, &io_data
->data
)) {
956 spin_lock_irq(&epfile
->ffs
->eps_lock
);
958 if (epfile
->ep
!= ep
) {
959 /* In the meantime, endpoint got disabled or changed. */
962 ret
= usb_ep_set_halt(ep
->ep
);
965 } else if (unlikely(data_len
== -EINVAL
)) {
967 * Sanity Check: even though data_len can't be used
968 * uninitialized at the time I write this comment, some
969 * compilers complain about this situation.
970 * In order to keep the code clean from warnings, data_len is
971 * being initialized to -EINVAL during its declaration, which
972 * means we can't rely on compiler anymore to warn no future
973 * changes won't result in data_len being used uninitialized.
974 * For such reason, we're adding this redundant sanity check
977 WARN(1, "%s: data_len == -EINVAL\n", __func__
);
979 } else if (!io_data
->aio
) {
980 DECLARE_COMPLETION_ONSTACK(done
);
981 bool interrupted
= false;
985 req
->length
= data_len
;
987 req
->context
= &done
;
988 req
->complete
= ffs_epfile_io_complete
;
990 ret
= usb_ep_queue(ep
->ep
, req
, GFP_ATOMIC
);
991 if (unlikely(ret
< 0))
994 spin_unlock_irq(&epfile
->ffs
->eps_lock
);
996 if (unlikely(wait_for_completion_interruptible(&done
))) {
998 * To avoid race condition with ffs_epfile_io_complete,
999 * dequeue the request first then check
1000 * status. usb_ep_dequeue API should guarantee no race
1001 * condition with req->complete callback.
1003 usb_ep_dequeue(ep
->ep
, req
);
1004 interrupted
= ep
->status
< 0;
1009 else if (io_data
->read
&& ep
->status
> 0)
1010 ret
= __ffs_epfile_read_data(epfile
, data
, ep
->status
,
1015 } else if (!(req
= usb_ep_alloc_request(ep
->ep
, GFP_KERNEL
))) {
1019 req
->length
= data_len
;
1021 io_data
->buf
= data
;
1022 io_data
->ep
= ep
->ep
;
1024 io_data
->ffs
= epfile
->ffs
;
1026 req
->context
= io_data
;
1027 req
->complete
= ffs_epfile_async_io_complete
;
1029 ret
= usb_ep_queue(ep
->ep
, req
, GFP_ATOMIC
);
1030 if (unlikely(ret
)) {
1031 usb_ep_free_request(ep
->ep
, req
);
1037 * Do not kfree the buffer in this function. It will be freed
1038 * by ffs_user_copy_worker.
1044 spin_unlock_irq(&epfile
->ffs
->eps_lock
);
1046 mutex_unlock(&epfile
->mutex
);
1053 ffs_epfile_open(struct inode
*inode
, struct file
*file
)
1055 struct ffs_epfile
*epfile
= inode
->i_private
;
1059 if (WARN_ON(epfile
->ffs
->state
!= FFS_ACTIVE
))
1062 file
->private_data
= epfile
;
1063 ffs_data_opened(epfile
->ffs
);
1068 static int ffs_aio_cancel(struct kiocb
*kiocb
)
1070 struct ffs_io_data
*io_data
= kiocb
->private;
1071 struct ffs_epfile
*epfile
= kiocb
->ki_filp
->private_data
;
1076 spin_lock_irq(&epfile
->ffs
->eps_lock
);
1078 if (likely(io_data
&& io_data
->ep
&& io_data
->req
))
1079 value
= usb_ep_dequeue(io_data
->ep
, io_data
->req
);
1083 spin_unlock_irq(&epfile
->ffs
->eps_lock
);
1088 static ssize_t
ffs_epfile_write_iter(struct kiocb
*kiocb
, struct iov_iter
*from
)
1090 struct ffs_io_data io_data
, *p
= &io_data
;
1095 if (!is_sync_kiocb(kiocb
)) {
1096 p
= kmalloc(sizeof(io_data
), GFP_KERNEL
);
1107 p
->mm
= current
->mm
;
1112 kiocb_set_cancel_fn(kiocb
, ffs_aio_cancel
);
1114 res
= ffs_epfile_io(kiocb
->ki_filp
, p
);
1115 if (res
== -EIOCBQUEUED
)
1124 static ssize_t
ffs_epfile_read_iter(struct kiocb
*kiocb
, struct iov_iter
*to
)
1126 struct ffs_io_data io_data
, *p
= &io_data
;
1131 if (!is_sync_kiocb(kiocb
)) {
1132 p
= kmalloc(sizeof(io_data
), GFP_KERNEL
);
1143 p
->to_free
= dup_iter(&p
->data
, to
, GFP_KERNEL
);
1152 p
->mm
= current
->mm
;
1157 kiocb_set_cancel_fn(kiocb
, ffs_aio_cancel
);
1159 res
= ffs_epfile_io(kiocb
->ki_filp
, p
);
1160 if (res
== -EIOCBQUEUED
)
1173 ffs_epfile_release(struct inode
*inode
, struct file
*file
)
1175 struct ffs_epfile
*epfile
= inode
->i_private
;
1179 __ffs_epfile_read_buffer_free(epfile
);
1180 ffs_data_closed(epfile
->ffs
);
1185 static long ffs_epfile_ioctl(struct file
*file
, unsigned code
,
1186 unsigned long value
)
1188 struct ffs_epfile
*epfile
= file
->private_data
;
1194 if (WARN_ON(epfile
->ffs
->state
!= FFS_ACTIVE
))
1197 /* Wait for endpoint to be enabled */
1200 if (file
->f_flags
& O_NONBLOCK
)
1203 ret
= wait_event_interruptible(
1204 epfile
->ffs
->wait
, (ep
= epfile
->ep
));
1209 spin_lock_irq(&epfile
->ffs
->eps_lock
);
1211 /* In the meantime, endpoint got disabled or changed. */
1212 if (epfile
->ep
!= ep
) {
1213 spin_unlock_irq(&epfile
->ffs
->eps_lock
);
1218 case FUNCTIONFS_FIFO_STATUS
:
1219 ret
= usb_ep_fifo_status(epfile
->ep
->ep
);
1221 case FUNCTIONFS_FIFO_FLUSH
:
1222 usb_ep_fifo_flush(epfile
->ep
->ep
);
1225 case FUNCTIONFS_CLEAR_HALT
:
1226 ret
= usb_ep_clear_halt(epfile
->ep
->ep
);
1228 case FUNCTIONFS_ENDPOINT_REVMAP
:
1229 ret
= epfile
->ep
->num
;
1231 case FUNCTIONFS_ENDPOINT_DESC
:
1234 struct usb_endpoint_descriptor
*desc
;
1236 switch (epfile
->ffs
->gadget
->speed
) {
1237 case USB_SPEED_SUPER
:
1240 case USB_SPEED_HIGH
:
1246 desc
= epfile
->ep
->descs
[desc_idx
];
1248 spin_unlock_irq(&epfile
->ffs
->eps_lock
);
1249 ret
= copy_to_user((void *)value
, desc
, desc
->bLength
);
1257 spin_unlock_irq(&epfile
->ffs
->eps_lock
);
1262 static const struct file_operations ffs_epfile_operations
= {
1263 .llseek
= no_llseek
,
1265 .open
= ffs_epfile_open
,
1266 .write_iter
= ffs_epfile_write_iter
,
1267 .read_iter
= ffs_epfile_read_iter
,
1268 .release
= ffs_epfile_release
,
1269 .unlocked_ioctl
= ffs_epfile_ioctl
,
1273 /* File system and super block operations ***********************************/
1276 * Mounting the file system creates a controller file, used first for
1277 * function configuration then later for event monitoring.
1280 static struct inode
*__must_check
1281 ffs_sb_make_inode(struct super_block
*sb
, void *data
,
1282 const struct file_operations
*fops
,
1283 const struct inode_operations
*iops
,
1284 struct ffs_file_perms
*perms
)
1286 struct inode
*inode
;
1290 inode
= new_inode(sb
);
1292 if (likely(inode
)) {
1293 struct timespec ts
= current_time(inode
);
1295 inode
->i_ino
= get_next_ino();
1296 inode
->i_mode
= perms
->mode
;
1297 inode
->i_uid
= perms
->uid
;
1298 inode
->i_gid
= perms
->gid
;
1299 inode
->i_atime
= ts
;
1300 inode
->i_mtime
= ts
;
1301 inode
->i_ctime
= ts
;
1302 inode
->i_private
= data
;
1304 inode
->i_fop
= fops
;
1312 /* Create "regular" file */
1313 static struct dentry
*ffs_sb_create_file(struct super_block
*sb
,
1314 const char *name
, void *data
,
1315 const struct file_operations
*fops
)
1317 struct ffs_data
*ffs
= sb
->s_fs_info
;
1318 struct dentry
*dentry
;
1319 struct inode
*inode
;
1323 dentry
= d_alloc_name(sb
->s_root
, name
);
1324 if (unlikely(!dentry
))
1327 inode
= ffs_sb_make_inode(sb
, data
, fops
, NULL
, &ffs
->file_perms
);
1328 if (unlikely(!inode
)) {
1333 d_add(dentry
, inode
);
1338 static const struct super_operations ffs_sb_operations
= {
1339 .statfs
= simple_statfs
,
1340 .drop_inode
= generic_delete_inode
,
1343 struct ffs_sb_fill_data
{
1344 struct ffs_file_perms perms
;
1346 const char *dev_name
;
1348 struct ffs_data
*ffs_data
;
1351 static int ffs_sb_fill(struct super_block
*sb
, void *_data
, int silent
)
1353 struct ffs_sb_fill_data
*data
= _data
;
1354 struct inode
*inode
;
1355 struct ffs_data
*ffs
= data
->ffs_data
;
1360 data
->ffs_data
= NULL
;
1361 sb
->s_fs_info
= ffs
;
1362 sb
->s_blocksize
= PAGE_SIZE
;
1363 sb
->s_blocksize_bits
= PAGE_SHIFT
;
1364 sb
->s_magic
= FUNCTIONFS_MAGIC
;
1365 sb
->s_op
= &ffs_sb_operations
;
1366 sb
->s_time_gran
= 1;
1369 data
->perms
.mode
= data
->root_mode
;
1370 inode
= ffs_sb_make_inode(sb
, NULL
,
1371 &simple_dir_operations
,
1372 &simple_dir_inode_operations
,
1374 sb
->s_root
= d_make_root(inode
);
1375 if (unlikely(!sb
->s_root
))
1379 if (unlikely(!ffs_sb_create_file(sb
, "ep0", ffs
,
1380 &ffs_ep0_operations
)))
1386 static int ffs_fs_parse_opts(struct ffs_sb_fill_data
*data
, char *opts
)
1390 if (!opts
|| !*opts
)
1394 unsigned long value
;
1398 comma
= strchr(opts
, ',');
1403 eq
= strchr(opts
, '=');
1404 if (unlikely(!eq
)) {
1405 pr_err("'=' missing in %s\n", opts
);
1411 if (kstrtoul(eq
+ 1, 0, &value
)) {
1412 pr_err("%s: invalid value: %s\n", opts
, eq
+ 1);
1416 /* Interpret option */
1417 switch (eq
- opts
) {
1419 if (!memcmp(opts
, "no_disconnect", 13))
1420 data
->no_disconnect
= !!value
;
1425 if (!memcmp(opts
, "rmode", 5))
1426 data
->root_mode
= (value
& 0555) | S_IFDIR
;
1427 else if (!memcmp(opts
, "fmode", 5))
1428 data
->perms
.mode
= (value
& 0666) | S_IFREG
;
1434 if (!memcmp(opts
, "mode", 4)) {
1435 data
->root_mode
= (value
& 0555) | S_IFDIR
;
1436 data
->perms
.mode
= (value
& 0666) | S_IFREG
;
1443 if (!memcmp(opts
, "uid", 3)) {
1444 data
->perms
.uid
= make_kuid(current_user_ns(), value
);
1445 if (!uid_valid(data
->perms
.uid
)) {
1446 pr_err("%s: unmapped value: %lu\n", opts
, value
);
1449 } else if (!memcmp(opts
, "gid", 3)) {
1450 data
->perms
.gid
= make_kgid(current_user_ns(), value
);
1451 if (!gid_valid(data
->perms
.gid
)) {
1452 pr_err("%s: unmapped value: %lu\n", opts
, value
);
1462 pr_err("%s: invalid option\n", opts
);
1466 /* Next iteration */
1475 /* "mount -t functionfs dev_name /dev/function" ends up here */
1477 static struct dentry
*
1478 ffs_fs_mount(struct file_system_type
*t
, int flags
,
1479 const char *dev_name
, void *opts
)
1481 struct ffs_sb_fill_data data
= {
1483 .mode
= S_IFREG
| 0600,
1484 .uid
= GLOBAL_ROOT_UID
,
1485 .gid
= GLOBAL_ROOT_GID
,
1487 .root_mode
= S_IFDIR
| 0500,
1488 .no_disconnect
= false,
1493 struct ffs_data
*ffs
;
1497 ret
= ffs_fs_parse_opts(&data
, opts
);
1498 if (unlikely(ret
< 0))
1499 return ERR_PTR(ret
);
1501 ffs
= ffs_data_new(dev_name
);
1503 return ERR_PTR(-ENOMEM
);
1504 ffs
->file_perms
= data
.perms
;
1505 ffs
->no_disconnect
= data
.no_disconnect
;
1507 ffs
->dev_name
= kstrdup(dev_name
, GFP_KERNEL
);
1508 if (unlikely(!ffs
->dev_name
)) {
1510 return ERR_PTR(-ENOMEM
);
1513 ffs_dev
= ffs_acquire_dev(dev_name
);
1514 if (IS_ERR(ffs_dev
)) {
1516 return ERR_CAST(ffs_dev
);
1518 ffs
->private_data
= ffs_dev
;
1519 data
.ffs_data
= ffs
;
1521 rv
= mount_nodev(t
, flags
, &data
, ffs_sb_fill
);
1522 if (IS_ERR(rv
) && data
.ffs_data
) {
1523 ffs_release_dev(data
.ffs_data
);
1524 ffs_data_put(data
.ffs_data
);
1530 ffs_fs_kill_sb(struct super_block
*sb
)
1534 kill_litter_super(sb
);
1535 if (sb
->s_fs_info
) {
1536 ffs_release_dev(sb
->s_fs_info
);
1537 ffs_data_closed(sb
->s_fs_info
);
1538 ffs_data_put(sb
->s_fs_info
);
1542 static struct file_system_type ffs_fs_type
= {
1543 .owner
= THIS_MODULE
,
1544 .name
= "functionfs",
1545 .mount
= ffs_fs_mount
,
1546 .kill_sb
= ffs_fs_kill_sb
,
1548 MODULE_ALIAS_FS("functionfs");
1551 /* Driver's main init/cleanup functions *************************************/
1553 static int functionfs_init(void)
1559 ret
= register_filesystem(&ffs_fs_type
);
1561 pr_info("file system registered\n");
1563 pr_err("failed registering file system (%d)\n", ret
);
1568 static void functionfs_cleanup(void)
1572 pr_info("unloading\n");
1573 unregister_filesystem(&ffs_fs_type
);
1577 /* ffs_data and ffs_function construction and destruction code **************/
1579 static void ffs_data_clear(struct ffs_data
*ffs
);
1580 static void ffs_data_reset(struct ffs_data
*ffs
);
1582 static void ffs_data_get(struct ffs_data
*ffs
)
1586 refcount_inc(&ffs
->ref
);
1589 static void ffs_data_opened(struct ffs_data
*ffs
)
1593 refcount_inc(&ffs
->ref
);
1594 if (atomic_add_return(1, &ffs
->opened
) == 1 &&
1595 ffs
->state
== FFS_DEACTIVATED
) {
1596 ffs
->state
= FFS_CLOSING
;
1597 ffs_data_reset(ffs
);
1601 static void ffs_data_put(struct ffs_data
*ffs
)
1605 if (unlikely(refcount_dec_and_test(&ffs
->ref
))) {
1606 pr_info("%s(): freeing\n", __func__
);
1607 ffs_data_clear(ffs
);
1608 BUG_ON(waitqueue_active(&ffs
->ev
.waitq
) ||
1609 waitqueue_active(&ffs
->ep0req_completion
.wait
) ||
1610 waitqueue_active(&ffs
->wait
));
1611 destroy_workqueue(ffs
->io_completion_wq
);
1612 kfree(ffs
->dev_name
);
1617 static void ffs_data_closed(struct ffs_data
*ffs
)
1621 if (atomic_dec_and_test(&ffs
->opened
)) {
1622 if (ffs
->no_disconnect
) {
1623 ffs
->state
= FFS_DEACTIVATED
;
1625 ffs_epfiles_destroy(ffs
->epfiles
,
1627 ffs
->epfiles
= NULL
;
1629 if (ffs
->setup_state
== FFS_SETUP_PENDING
)
1630 __ffs_ep0_stall(ffs
);
1632 ffs
->state
= FFS_CLOSING
;
1633 ffs_data_reset(ffs
);
1636 if (atomic_read(&ffs
->opened
) < 0) {
1637 ffs
->state
= FFS_CLOSING
;
1638 ffs_data_reset(ffs
);
1644 static struct ffs_data
*ffs_data_new(const char *dev_name
)
1646 struct ffs_data
*ffs
= kzalloc(sizeof *ffs
, GFP_KERNEL
);
1652 ffs
->io_completion_wq
= alloc_ordered_workqueue("%s", 0, dev_name
);
1653 if (!ffs
->io_completion_wq
) {
1658 refcount_set(&ffs
->ref
, 1);
1659 atomic_set(&ffs
->opened
, 0);
1660 ffs
->state
= FFS_READ_DESCRIPTORS
;
1661 mutex_init(&ffs
->mutex
);
1662 spin_lock_init(&ffs
->eps_lock
);
1663 init_waitqueue_head(&ffs
->ev
.waitq
);
1664 init_waitqueue_head(&ffs
->wait
);
1665 init_completion(&ffs
->ep0req_completion
);
1667 /* XXX REVISIT need to update it in some places, or do we? */
1668 ffs
->ev
.can_stall
= 1;
1673 static void ffs_data_clear(struct ffs_data
*ffs
)
1679 BUG_ON(ffs
->gadget
);
1682 ffs_epfiles_destroy(ffs
->epfiles
, ffs
->eps_count
);
1684 if (ffs
->ffs_eventfd
)
1685 eventfd_ctx_put(ffs
->ffs_eventfd
);
1687 kfree(ffs
->raw_descs_data
);
1688 kfree(ffs
->raw_strings
);
1689 kfree(ffs
->stringtabs
);
1692 static void ffs_data_reset(struct ffs_data
*ffs
)
1696 ffs_data_clear(ffs
);
1698 ffs
->epfiles
= NULL
;
1699 ffs
->raw_descs_data
= NULL
;
1700 ffs
->raw_descs
= NULL
;
1701 ffs
->raw_strings
= NULL
;
1702 ffs
->stringtabs
= NULL
;
1704 ffs
->raw_descs_length
= 0;
1705 ffs
->fs_descs_count
= 0;
1706 ffs
->hs_descs_count
= 0;
1707 ffs
->ss_descs_count
= 0;
1709 ffs
->strings_count
= 0;
1710 ffs
->interfaces_count
= 0;
1715 ffs
->state
= FFS_READ_DESCRIPTORS
;
1716 ffs
->setup_state
= FFS_NO_SETUP
;
1721 static int functionfs_bind(struct ffs_data
*ffs
, struct usb_composite_dev
*cdev
)
1723 struct usb_gadget_strings
**lang
;
1728 if (WARN_ON(ffs
->state
!= FFS_ACTIVE
1729 || test_and_set_bit(FFS_FL_BOUND
, &ffs
->flags
)))
1732 first_id
= usb_string_ids_n(cdev
, ffs
->strings_count
);
1733 if (unlikely(first_id
< 0))
1736 ffs
->ep0req
= usb_ep_alloc_request(cdev
->gadget
->ep0
, GFP_KERNEL
);
1737 if (unlikely(!ffs
->ep0req
))
1739 ffs
->ep0req
->complete
= ffs_ep0_complete
;
1740 ffs
->ep0req
->context
= ffs
;
1742 lang
= ffs
->stringtabs
;
1744 for (; *lang
; ++lang
) {
1745 struct usb_string
*str
= (*lang
)->strings
;
1747 for (; str
->s
; ++id
, ++str
)
1752 ffs
->gadget
= cdev
->gadget
;
1757 static void functionfs_unbind(struct ffs_data
*ffs
)
1761 if (!WARN_ON(!ffs
->gadget
)) {
1762 usb_ep_free_request(ffs
->gadget
->ep0
, ffs
->ep0req
);
1765 clear_bit(FFS_FL_BOUND
, &ffs
->flags
);
1770 static int ffs_epfiles_create(struct ffs_data
*ffs
)
1772 struct ffs_epfile
*epfile
, *epfiles
;
1777 count
= ffs
->eps_count
;
1778 epfiles
= kcalloc(count
, sizeof(*epfiles
), GFP_KERNEL
);
1783 for (i
= 1; i
<= count
; ++i
, ++epfile
) {
1785 mutex_init(&epfile
->mutex
);
1786 if (ffs
->user_flags
& FUNCTIONFS_VIRTUAL_ADDR
)
1787 sprintf(epfile
->name
, "ep%02x", ffs
->eps_addrmap
[i
]);
1789 sprintf(epfile
->name
, "ep%u", i
);
1790 epfile
->dentry
= ffs_sb_create_file(ffs
->sb
, epfile
->name
,
1792 &ffs_epfile_operations
);
1793 if (unlikely(!epfile
->dentry
)) {
1794 ffs_epfiles_destroy(epfiles
, i
- 1);
1799 ffs
->epfiles
= epfiles
;
1803 static void ffs_epfiles_destroy(struct ffs_epfile
*epfiles
, unsigned count
)
1805 struct ffs_epfile
*epfile
= epfiles
;
1809 for (; count
; --count
, ++epfile
) {
1810 BUG_ON(mutex_is_locked(&epfile
->mutex
));
1811 if (epfile
->dentry
) {
1812 d_delete(epfile
->dentry
);
1813 dput(epfile
->dentry
);
1814 epfile
->dentry
= NULL
;
1821 static void ffs_func_eps_disable(struct ffs_function
*func
)
1823 struct ffs_ep
*ep
= func
->eps
;
1824 struct ffs_epfile
*epfile
= func
->ffs
->epfiles
;
1825 unsigned count
= func
->ffs
->eps_count
;
1826 unsigned long flags
;
1828 spin_lock_irqsave(&func
->ffs
->eps_lock
, flags
);
1830 /* pending requests get nuked */
1832 usb_ep_disable(ep
->ep
);
1837 __ffs_epfile_read_buffer_free(epfile
);
1841 spin_unlock_irqrestore(&func
->ffs
->eps_lock
, flags
);
1844 static int ffs_func_eps_enable(struct ffs_function
*func
)
1846 struct ffs_data
*ffs
= func
->ffs
;
1847 struct ffs_ep
*ep
= func
->eps
;
1848 struct ffs_epfile
*epfile
= ffs
->epfiles
;
1849 unsigned count
= ffs
->eps_count
;
1850 unsigned long flags
;
1853 spin_lock_irqsave(&func
->ffs
->eps_lock
, flags
);
1855 struct usb_endpoint_descriptor
*ds
;
1856 struct usb_ss_ep_comp_descriptor
*comp_desc
= NULL
;
1857 int needs_comp_desc
= false;
1860 if (ffs
->gadget
->speed
== USB_SPEED_SUPER
) {
1862 needs_comp_desc
= true;
1863 } else if (ffs
->gadget
->speed
== USB_SPEED_HIGH
)
1868 /* fall-back to lower speed if desc missing for current speed */
1870 ds
= ep
->descs
[desc_idx
];
1871 } while (!ds
&& --desc_idx
>= 0);
1878 ep
->ep
->driver_data
= ep
;
1881 if (needs_comp_desc
) {
1882 comp_desc
= (struct usb_ss_ep_comp_descriptor
*)(ds
+
1883 USB_DT_ENDPOINT_SIZE
);
1884 ep
->ep
->maxburst
= comp_desc
->bMaxBurst
+ 1;
1885 ep
->ep
->comp_desc
= comp_desc
;
1888 ret
= usb_ep_enable(ep
->ep
);
1891 epfile
->in
= usb_endpoint_dir_in(ds
);
1892 epfile
->isoc
= usb_endpoint_xfer_isoc(ds
);
1901 wake_up_interruptible(&ffs
->wait
);
1902 spin_unlock_irqrestore(&func
->ffs
->eps_lock
, flags
);
1908 /* Parsing and building descriptors and strings *****************************/
1911 * This validates if data pointed by data is a valid USB descriptor as
1912 * well as record how many interfaces, endpoints and strings are
1913 * required by given configuration. Returns address after the
1914 * descriptor or NULL if data is invalid.
1917 enum ffs_entity_type
{
1918 FFS_DESCRIPTOR
, FFS_INTERFACE
, FFS_STRING
, FFS_ENDPOINT
1921 enum ffs_os_desc_type
{
1922 FFS_OS_DESC
, FFS_OS_DESC_EXT_COMPAT
, FFS_OS_DESC_EXT_PROP
1925 typedef int (*ffs_entity_callback
)(enum ffs_entity_type entity
,
1927 struct usb_descriptor_header
*desc
,
1930 typedef int (*ffs_os_desc_callback
)(enum ffs_os_desc_type entity
,
1931 struct usb_os_desc_header
*h
, void *data
,
1932 unsigned len
, void *priv
);
1934 static int __must_check
ffs_do_single_desc(char *data
, unsigned len
,
1935 ffs_entity_callback entity
,
1938 struct usb_descriptor_header
*_ds
= (void *)data
;
1944 /* At least two bytes are required: length and type */
1946 pr_vdebug("descriptor too short\n");
1950 /* If we have at least as many bytes as the descriptor takes? */
1951 length
= _ds
->bLength
;
1953 pr_vdebug("descriptor longer then available data\n");
1957 #define __entity_check_INTERFACE(val) 1
1958 #define __entity_check_STRING(val) (val)
1959 #define __entity_check_ENDPOINT(val) ((val) & USB_ENDPOINT_NUMBER_MASK)
1960 #define __entity(type, val) do { \
1961 pr_vdebug("entity " #type "(%02x)\n", (val)); \
1962 if (unlikely(!__entity_check_ ##type(val))) { \
1963 pr_vdebug("invalid entity's value\n"); \
1966 ret = entity(FFS_ ##type, &val, _ds, priv); \
1967 if (unlikely(ret < 0)) { \
1968 pr_debug("entity " #type "(%02x); ret = %d\n", \
1974 /* Parse descriptor depending on type. */
1975 switch (_ds
->bDescriptorType
) {
1979 case USB_DT_DEVICE_QUALIFIER
:
1980 /* function can't have any of those */
1981 pr_vdebug("descriptor reserved for gadget: %d\n",
1982 _ds
->bDescriptorType
);
1985 case USB_DT_INTERFACE
: {
1986 struct usb_interface_descriptor
*ds
= (void *)_ds
;
1987 pr_vdebug("interface descriptor\n");
1988 if (length
!= sizeof *ds
)
1991 __entity(INTERFACE
, ds
->bInterfaceNumber
);
1993 __entity(STRING
, ds
->iInterface
);
1997 case USB_DT_ENDPOINT
: {
1998 struct usb_endpoint_descriptor
*ds
= (void *)_ds
;
1999 pr_vdebug("endpoint descriptor\n");
2000 if (length
!= USB_DT_ENDPOINT_SIZE
&&
2001 length
!= USB_DT_ENDPOINT_AUDIO_SIZE
)
2003 __entity(ENDPOINT
, ds
->bEndpointAddress
);
2008 pr_vdebug("hid descriptor\n");
2009 if (length
!= sizeof(struct hid_descriptor
))
2014 if (length
!= sizeof(struct usb_otg_descriptor
))
2018 case USB_DT_INTERFACE_ASSOCIATION
: {
2019 struct usb_interface_assoc_descriptor
*ds
= (void *)_ds
;
2020 pr_vdebug("interface association descriptor\n");
2021 if (length
!= sizeof *ds
)
2024 __entity(STRING
, ds
->iFunction
);
2028 case USB_DT_SS_ENDPOINT_COMP
:
2029 pr_vdebug("EP SS companion descriptor\n");
2030 if (length
!= sizeof(struct usb_ss_ep_comp_descriptor
))
2034 case USB_DT_OTHER_SPEED_CONFIG
:
2035 case USB_DT_INTERFACE_POWER
:
2037 case USB_DT_SECURITY
:
2038 case USB_DT_CS_RADIO_CONTROL
:
2040 pr_vdebug("unimplemented descriptor: %d\n", _ds
->bDescriptorType
);
2044 /* We should never be here */
2045 pr_vdebug("unknown descriptor: %d\n", _ds
->bDescriptorType
);
2049 pr_vdebug("invalid length: %d (descriptor %d)\n",
2050 _ds
->bLength
, _ds
->bDescriptorType
);
2055 #undef __entity_check_DESCRIPTOR
2056 #undef __entity_check_INTERFACE
2057 #undef __entity_check_STRING
2058 #undef __entity_check_ENDPOINT
2063 static int __must_check
ffs_do_descs(unsigned count
, char *data
, unsigned len
,
2064 ffs_entity_callback entity
, void *priv
)
2066 const unsigned _len
= len
;
2067 unsigned long num
= 0;
2077 /* Record "descriptor" entity */
2078 ret
= entity(FFS_DESCRIPTOR
, (u8
*)num
, (void *)data
, priv
);
2079 if (unlikely(ret
< 0)) {
2080 pr_debug("entity DESCRIPTOR(%02lx); ret = %d\n",
2088 ret
= ffs_do_single_desc(data
, len
, entity
, priv
);
2089 if (unlikely(ret
< 0)) {
2090 pr_debug("%s returns %d\n", __func__
, ret
);
2100 static int __ffs_data_do_entity(enum ffs_entity_type type
,
2101 u8
*valuep
, struct usb_descriptor_header
*desc
,
2104 struct ffs_desc_helper
*helper
= priv
;
2105 struct usb_endpoint_descriptor
*d
;
2110 case FFS_DESCRIPTOR
:
2115 * Interfaces are indexed from zero so if we
2116 * encountered interface "n" then there are at least
2119 if (*valuep
>= helper
->interfaces_count
)
2120 helper
->interfaces_count
= *valuep
+ 1;
2125 * Strings are indexed from 1 (0 is reserved
2126 * for languages list)
2128 if (*valuep
> helper
->ffs
->strings_count
)
2129 helper
->ffs
->strings_count
= *valuep
;
2134 helper
->eps_count
++;
2135 if (helper
->eps_count
>= FFS_MAX_EPS_COUNT
)
2137 /* Check if descriptors for any speed were already parsed */
2138 if (!helper
->ffs
->eps_count
&& !helper
->ffs
->interfaces_count
)
2139 helper
->ffs
->eps_addrmap
[helper
->eps_count
] =
2140 d
->bEndpointAddress
;
2141 else if (helper
->ffs
->eps_addrmap
[helper
->eps_count
] !=
2142 d
->bEndpointAddress
)
2150 static int __ffs_do_os_desc_header(enum ffs_os_desc_type
*next_type
,
2151 struct usb_os_desc_header
*desc
)
2153 u16 bcd_version
= le16_to_cpu(desc
->bcdVersion
);
2154 u16 w_index
= le16_to_cpu(desc
->wIndex
);
2156 if (bcd_version
!= 1) {
2157 pr_vdebug("unsupported os descriptors version: %d",
2163 *next_type
= FFS_OS_DESC_EXT_COMPAT
;
2166 *next_type
= FFS_OS_DESC_EXT_PROP
;
2169 pr_vdebug("unsupported os descriptor type: %d", w_index
);
2173 return sizeof(*desc
);
2177 * Process all extended compatibility/extended property descriptors
2178 * of a feature descriptor
2180 static int __must_check
ffs_do_single_os_desc(char *data
, unsigned len
,
2181 enum ffs_os_desc_type type
,
2183 ffs_os_desc_callback entity
,
2185 struct usb_os_desc_header
*h
)
2188 const unsigned _len
= len
;
2192 /* loop over all ext compat/ext prop descriptors */
2193 while (feature_count
--) {
2194 ret
= entity(type
, h
, data
, len
, priv
);
2195 if (unlikely(ret
< 0)) {
2196 pr_debug("bad OS descriptor, type: %d\n", type
);
2205 /* Process a number of complete Feature Descriptors (Ext Compat or Ext Prop) */
2206 static int __must_check
ffs_do_os_descs(unsigned count
,
2207 char *data
, unsigned len
,
2208 ffs_os_desc_callback entity
, void *priv
)
2210 const unsigned _len
= len
;
2211 unsigned long num
= 0;
2215 for (num
= 0; num
< count
; ++num
) {
2217 enum ffs_os_desc_type type
;
2219 struct usb_os_desc_header
*desc
= (void *)data
;
2221 if (len
< sizeof(*desc
))
2225 * Record "descriptor" entity.
2226 * Process dwLength, bcdVersion, wIndex, get b/wCount.
2227 * Move the data pointer to the beginning of extended
2228 * compatibilities proper or extended properties proper
2229 * portions of the data
2231 if (le32_to_cpu(desc
->dwLength
) > len
)
2234 ret
= __ffs_do_os_desc_header(&type
, desc
);
2235 if (unlikely(ret
< 0)) {
2236 pr_debug("entity OS_DESCRIPTOR(%02lx); ret = %d\n",
2241 * 16-bit hex "?? 00" Little Endian looks like 8-bit hex "??"
2243 feature_count
= le16_to_cpu(desc
->wCount
);
2244 if (type
== FFS_OS_DESC_EXT_COMPAT
&&
2245 (feature_count
> 255 || desc
->Reserved
))
2251 * Process all function/property descriptors
2252 * of this Feature Descriptor
2254 ret
= ffs_do_single_os_desc(data
, len
, type
,
2255 feature_count
, entity
, priv
, desc
);
2256 if (unlikely(ret
< 0)) {
2257 pr_debug("%s returns %d\n", __func__
, ret
);
2268 * Validate contents of the buffer from userspace related to OS descriptors.
2270 static int __ffs_data_do_os_desc(enum ffs_os_desc_type type
,
2271 struct usb_os_desc_header
*h
, void *data
,
2272 unsigned len
, void *priv
)
2274 struct ffs_data
*ffs
= priv
;
2280 case FFS_OS_DESC_EXT_COMPAT
: {
2281 struct usb_ext_compat_desc
*d
= data
;
2284 if (len
< sizeof(*d
) ||
2285 d
->bFirstInterfaceNumber
>= ffs
->interfaces_count
||
2288 for (i
= 0; i
< ARRAY_SIZE(d
->Reserved2
); ++i
)
2289 if (d
->Reserved2
[i
])
2292 length
= sizeof(struct usb_ext_compat_desc
);
2295 case FFS_OS_DESC_EXT_PROP
: {
2296 struct usb_ext_prop_desc
*d
= data
;
2300 if (len
< sizeof(*d
) || h
->interface
>= ffs
->interfaces_count
)
2302 length
= le32_to_cpu(d
->dwSize
);
2305 type
= le32_to_cpu(d
->dwPropertyDataType
);
2306 if (type
< USB_EXT_PROP_UNICODE
||
2307 type
> USB_EXT_PROP_UNICODE_MULTI
) {
2308 pr_vdebug("unsupported os descriptor property type: %d",
2312 pnl
= le16_to_cpu(d
->wPropertyNameLength
);
2313 if (length
< 14 + pnl
) {
2314 pr_vdebug("invalid os descriptor length: %d pnl:%d (descriptor %d)\n",
2318 pdl
= le32_to_cpu(*(u32
*)((u8
*)data
+ 10 + pnl
));
2319 if (length
!= 14 + pnl
+ pdl
) {
2320 pr_vdebug("invalid os descriptor length: %d pnl:%d pdl:%d (descriptor %d)\n",
2321 length
, pnl
, pdl
, type
);
2324 ++ffs
->ms_os_descs_ext_prop_count
;
2325 /* property name reported to the host as "WCHAR"s */
2326 ffs
->ms_os_descs_ext_prop_name_len
+= pnl
* 2;
2327 ffs
->ms_os_descs_ext_prop_data_len
+= pdl
;
2331 pr_vdebug("unknown descriptor: %d\n", type
);
2337 static int __ffs_data_got_descs(struct ffs_data
*ffs
,
2338 char *const _data
, size_t len
)
2340 char *data
= _data
, *raw_descs
;
2341 unsigned os_descs_count
= 0, counts
[3], flags
;
2342 int ret
= -EINVAL
, i
;
2343 struct ffs_desc_helper helper
;
2347 if (get_unaligned_le32(data
+ 4) != len
)
2350 switch (get_unaligned_le32(data
)) {
2351 case FUNCTIONFS_DESCRIPTORS_MAGIC
:
2352 flags
= FUNCTIONFS_HAS_FS_DESC
| FUNCTIONFS_HAS_HS_DESC
;
2356 case FUNCTIONFS_DESCRIPTORS_MAGIC_V2
:
2357 flags
= get_unaligned_le32(data
+ 8);
2358 ffs
->user_flags
= flags
;
2359 if (flags
& ~(FUNCTIONFS_HAS_FS_DESC
|
2360 FUNCTIONFS_HAS_HS_DESC
|
2361 FUNCTIONFS_HAS_SS_DESC
|
2362 FUNCTIONFS_HAS_MS_OS_DESC
|
2363 FUNCTIONFS_VIRTUAL_ADDR
|
2364 FUNCTIONFS_EVENTFD
|
2365 FUNCTIONFS_ALL_CTRL_RECIP
|
2366 FUNCTIONFS_CONFIG0_SETUP
)) {
2377 if (flags
& FUNCTIONFS_EVENTFD
) {
2381 eventfd_ctx_fdget((int)get_unaligned_le32(data
));
2382 if (IS_ERR(ffs
->ffs_eventfd
)) {
2383 ret
= PTR_ERR(ffs
->ffs_eventfd
);
2384 ffs
->ffs_eventfd
= NULL
;
2391 /* Read fs_count, hs_count and ss_count (if present) */
2392 for (i
= 0; i
< 3; ++i
) {
2393 if (!(flags
& (1 << i
))) {
2395 } else if (len
< 4) {
2398 counts
[i
] = get_unaligned_le32(data
);
2403 if (flags
& (1 << i
)) {
2407 os_descs_count
= get_unaligned_le32(data
);
2412 /* Read descriptors */
2415 for (i
= 0; i
< 3; ++i
) {
2418 helper
.interfaces_count
= 0;
2419 helper
.eps_count
= 0;
2420 ret
= ffs_do_descs(counts
[i
], data
, len
,
2421 __ffs_data_do_entity
, &helper
);
2424 if (!ffs
->eps_count
&& !ffs
->interfaces_count
) {
2425 ffs
->eps_count
= helper
.eps_count
;
2426 ffs
->interfaces_count
= helper
.interfaces_count
;
2428 if (ffs
->eps_count
!= helper
.eps_count
) {
2432 if (ffs
->interfaces_count
!= helper
.interfaces_count
) {
2440 if (os_descs_count
) {
2441 ret
= ffs_do_os_descs(os_descs_count
, data
, len
,
2442 __ffs_data_do_os_desc
, ffs
);
2449 if (raw_descs
== data
|| len
) {
2454 ffs
->raw_descs_data
= _data
;
2455 ffs
->raw_descs
= raw_descs
;
2456 ffs
->raw_descs_length
= data
- raw_descs
;
2457 ffs
->fs_descs_count
= counts
[0];
2458 ffs
->hs_descs_count
= counts
[1];
2459 ffs
->ss_descs_count
= counts
[2];
2460 ffs
->ms_os_descs_count
= os_descs_count
;
2469 static int __ffs_data_got_strings(struct ffs_data
*ffs
,
2470 char *const _data
, size_t len
)
2472 u32 str_count
, needed_count
, lang_count
;
2473 struct usb_gadget_strings
**stringtabs
, *t
;
2474 const char *data
= _data
;
2475 struct usb_string
*s
;
2479 if (unlikely(len
< 16 ||
2480 get_unaligned_le32(data
) != FUNCTIONFS_STRINGS_MAGIC
||
2481 get_unaligned_le32(data
+ 4) != len
))
2483 str_count
= get_unaligned_le32(data
+ 8);
2484 lang_count
= get_unaligned_le32(data
+ 12);
2486 /* if one is zero the other must be zero */
2487 if (unlikely(!str_count
!= !lang_count
))
2490 /* Do we have at least as many strings as descriptors need? */
2491 needed_count
= ffs
->strings_count
;
2492 if (unlikely(str_count
< needed_count
))
2496 * If we don't need any strings just return and free all
2499 if (!needed_count
) {
2504 /* Allocate everything in one chunk so there's less maintenance. */
2508 vla_item(d
, struct usb_gadget_strings
*, stringtabs
,
2510 vla_item(d
, struct usb_gadget_strings
, stringtab
, lang_count
);
2511 vla_item(d
, struct usb_string
, strings
,
2512 lang_count
*(needed_count
+1));
2514 char *vlabuf
= kmalloc(vla_group_size(d
), GFP_KERNEL
);
2516 if (unlikely(!vlabuf
)) {
2521 /* Initialize the VLA pointers */
2522 stringtabs
= vla_ptr(vlabuf
, d
, stringtabs
);
2523 t
= vla_ptr(vlabuf
, d
, stringtab
);
2526 *stringtabs
++ = t
++;
2530 /* stringtabs = vlabuf = d_stringtabs for later kfree */
2531 stringtabs
= vla_ptr(vlabuf
, d
, stringtabs
);
2532 t
= vla_ptr(vlabuf
, d
, stringtab
);
2533 s
= vla_ptr(vlabuf
, d
, strings
);
2536 /* For each language */
2540 do { /* lang_count > 0 so we can use do-while */
2541 unsigned needed
= needed_count
;
2543 if (unlikely(len
< 3))
2545 t
->language
= get_unaligned_le16(data
);
2552 /* For each string */
2553 do { /* str_count > 0 so we can use do-while */
2554 size_t length
= strnlen(data
, len
);
2556 if (unlikely(length
== len
))
2560 * User may provide more strings then we need,
2561 * if that's the case we simply ignore the
2564 if (likely(needed
)) {
2566 * s->id will be set while adding
2567 * function to configuration so for
2568 * now just leave garbage here.
2577 } while (--str_count
);
2579 s
->id
= 0; /* terminator */
2583 } while (--lang_count
);
2585 /* Some garbage left? */
2590 ffs
->stringtabs
= stringtabs
;
2591 ffs
->raw_strings
= _data
;
2603 /* Events handling and management *******************************************/
2605 static void __ffs_event_add(struct ffs_data
*ffs
,
2606 enum usb_functionfs_event_type type
)
2608 enum usb_functionfs_event_type rem_type1
, rem_type2
= type
;
2612 * Abort any unhandled setup
2614 * We do not need to worry about some cmpxchg() changing value
2615 * of ffs->setup_state without holding the lock because when
2616 * state is FFS_SETUP_PENDING cmpxchg() in several places in
2617 * the source does nothing.
2619 if (ffs
->setup_state
== FFS_SETUP_PENDING
)
2620 ffs
->setup_state
= FFS_SETUP_CANCELLED
;
2623 * Logic of this function guarantees that there are at most four pending
2624 * evens on ffs->ev.types queue. This is important because the queue
2625 * has space for four elements only and __ffs_ep0_read_events function
2626 * depends on that limit as well. If more event types are added, those
2627 * limits have to be revisited or guaranteed to still hold.
2630 case FUNCTIONFS_RESUME
:
2631 rem_type2
= FUNCTIONFS_SUSPEND
;
2633 case FUNCTIONFS_SUSPEND
:
2634 case FUNCTIONFS_SETUP
:
2636 /* Discard all similar events */
2639 case FUNCTIONFS_BIND
:
2640 case FUNCTIONFS_UNBIND
:
2641 case FUNCTIONFS_DISABLE
:
2642 case FUNCTIONFS_ENABLE
:
2643 /* Discard everything other then power management. */
2644 rem_type1
= FUNCTIONFS_SUSPEND
;
2645 rem_type2
= FUNCTIONFS_RESUME
;
2650 WARN(1, "%d: unknown event, this should not happen\n", type
);
2655 u8
*ev
= ffs
->ev
.types
, *out
= ev
;
2656 unsigned n
= ffs
->ev
.count
;
2657 for (; n
; --n
, ++ev
)
2658 if ((*ev
== rem_type1
|| *ev
== rem_type2
) == neg
)
2661 pr_vdebug("purging event %d\n", *ev
);
2662 ffs
->ev
.count
= out
- ffs
->ev
.types
;
2665 pr_vdebug("adding event %d\n", type
);
2666 ffs
->ev
.types
[ffs
->ev
.count
++] = type
;
2667 wake_up_locked(&ffs
->ev
.waitq
);
2668 if (ffs
->ffs_eventfd
)
2669 eventfd_signal(ffs
->ffs_eventfd
, 1);
2672 static void ffs_event_add(struct ffs_data
*ffs
,
2673 enum usb_functionfs_event_type type
)
2675 unsigned long flags
;
2676 spin_lock_irqsave(&ffs
->ev
.waitq
.lock
, flags
);
2677 __ffs_event_add(ffs
, type
);
2678 spin_unlock_irqrestore(&ffs
->ev
.waitq
.lock
, flags
);
2681 /* Bind/unbind USB function hooks *******************************************/
2683 static int ffs_ep_addr2idx(struct ffs_data
*ffs
, u8 endpoint_address
)
2687 for (i
= 1; i
< ARRAY_SIZE(ffs
->eps_addrmap
); ++i
)
2688 if (ffs
->eps_addrmap
[i
] == endpoint_address
)
2693 static int __ffs_func_bind_do_descs(enum ffs_entity_type type
, u8
*valuep
,
2694 struct usb_descriptor_header
*desc
,
2697 struct usb_endpoint_descriptor
*ds
= (void *)desc
;
2698 struct ffs_function
*func
= priv
;
2699 struct ffs_ep
*ffs_ep
;
2700 unsigned ep_desc_id
;
2702 static const char *speed_names
[] = { "full", "high", "super" };
2704 if (type
!= FFS_DESCRIPTOR
)
2708 * If ss_descriptors is not NULL, we are reading super speed
2709 * descriptors; if hs_descriptors is not NULL, we are reading high
2710 * speed descriptors; otherwise, we are reading full speed
2713 if (func
->function
.ss_descriptors
) {
2715 func
->function
.ss_descriptors
[(long)valuep
] = desc
;
2716 } else if (func
->function
.hs_descriptors
) {
2718 func
->function
.hs_descriptors
[(long)valuep
] = desc
;
2721 func
->function
.fs_descriptors
[(long)valuep
] = desc
;
2724 if (!desc
|| desc
->bDescriptorType
!= USB_DT_ENDPOINT
)
2727 idx
= ffs_ep_addr2idx(func
->ffs
, ds
->bEndpointAddress
) - 1;
2731 ffs_ep
= func
->eps
+ idx
;
2733 if (unlikely(ffs_ep
->descs
[ep_desc_id
])) {
2734 pr_err("two %sspeed descriptors for EP %d\n",
2735 speed_names
[ep_desc_id
],
2736 ds
->bEndpointAddress
& USB_ENDPOINT_NUMBER_MASK
);
2739 ffs_ep
->descs
[ep_desc_id
] = ds
;
2741 ffs_dump_mem(": Original ep desc", ds
, ds
->bLength
);
2743 ds
->bEndpointAddress
= ffs_ep
->descs
[0]->bEndpointAddress
;
2744 if (!ds
->wMaxPacketSize
)
2745 ds
->wMaxPacketSize
= ffs_ep
->descs
[0]->wMaxPacketSize
;
2747 struct usb_request
*req
;
2749 u8 bEndpointAddress
;
2752 * We back up bEndpointAddress because autoconfig overwrites
2753 * it with physical endpoint address.
2755 bEndpointAddress
= ds
->bEndpointAddress
;
2756 pr_vdebug("autoconfig\n");
2757 ep
= usb_ep_autoconfig(func
->gadget
, ds
);
2760 ep
->driver_data
= func
->eps
+ idx
;
2762 req
= usb_ep_alloc_request(ep
, GFP_KERNEL
);
2768 func
->eps_revmap
[ds
->bEndpointAddress
&
2769 USB_ENDPOINT_NUMBER_MASK
] = idx
+ 1;
2771 * If we use virtual address mapping, we restore
2772 * original bEndpointAddress value.
2774 if (func
->ffs
->user_flags
& FUNCTIONFS_VIRTUAL_ADDR
)
2775 ds
->bEndpointAddress
= bEndpointAddress
;
2777 ffs_dump_mem(": Rewritten ep desc", ds
, ds
->bLength
);
2782 static int __ffs_func_bind_do_nums(enum ffs_entity_type type
, u8
*valuep
,
2783 struct usb_descriptor_header
*desc
,
2786 struct ffs_function
*func
= priv
;
2792 case FFS_DESCRIPTOR
:
2793 /* Handled in previous pass by __ffs_func_bind_do_descs() */
2798 if (func
->interfaces_nums
[idx
] < 0) {
2799 int id
= usb_interface_id(func
->conf
, &func
->function
);
2800 if (unlikely(id
< 0))
2802 func
->interfaces_nums
[idx
] = id
;
2804 newValue
= func
->interfaces_nums
[idx
];
2808 /* String' IDs are allocated when fsf_data is bound to cdev */
2809 newValue
= func
->ffs
->stringtabs
[0]->strings
[*valuep
- 1].id
;
2814 * USB_DT_ENDPOINT are handled in
2815 * __ffs_func_bind_do_descs().
2817 if (desc
->bDescriptorType
== USB_DT_ENDPOINT
)
2820 idx
= (*valuep
& USB_ENDPOINT_NUMBER_MASK
) - 1;
2821 if (unlikely(!func
->eps
[idx
].ep
))
2825 struct usb_endpoint_descriptor
**descs
;
2826 descs
= func
->eps
[idx
].descs
;
2827 newValue
= descs
[descs
[0] ? 0 : 1]->bEndpointAddress
;
2832 pr_vdebug("%02x -> %02x\n", *valuep
, newValue
);
2837 static int __ffs_func_bind_do_os_desc(enum ffs_os_desc_type type
,
2838 struct usb_os_desc_header
*h
, void *data
,
2839 unsigned len
, void *priv
)
2841 struct ffs_function
*func
= priv
;
2845 case FFS_OS_DESC_EXT_COMPAT
: {
2846 struct usb_ext_compat_desc
*desc
= data
;
2847 struct usb_os_desc_table
*t
;
2849 t
= &func
->function
.os_desc_table
[desc
->bFirstInterfaceNumber
];
2850 t
->if_id
= func
->interfaces_nums
[desc
->bFirstInterfaceNumber
];
2851 memcpy(t
->os_desc
->ext_compat_id
, &desc
->CompatibleID
,
2852 ARRAY_SIZE(desc
->CompatibleID
) +
2853 ARRAY_SIZE(desc
->SubCompatibleID
));
2854 length
= sizeof(*desc
);
2857 case FFS_OS_DESC_EXT_PROP
: {
2858 struct usb_ext_prop_desc
*desc
= data
;
2859 struct usb_os_desc_table
*t
;
2860 struct usb_os_desc_ext_prop
*ext_prop
;
2861 char *ext_prop_name
;
2862 char *ext_prop_data
;
2864 t
= &func
->function
.os_desc_table
[h
->interface
];
2865 t
->if_id
= func
->interfaces_nums
[h
->interface
];
2867 ext_prop
= func
->ffs
->ms_os_descs_ext_prop_avail
;
2868 func
->ffs
->ms_os_descs_ext_prop_avail
+= sizeof(*ext_prop
);
2870 ext_prop
->type
= le32_to_cpu(desc
->dwPropertyDataType
);
2871 ext_prop
->name_len
= le16_to_cpu(desc
->wPropertyNameLength
);
2872 ext_prop
->data_len
= le32_to_cpu(*(u32
*)
2873 usb_ext_prop_data_len_ptr(data
, ext_prop
->name_len
));
2874 length
= ext_prop
->name_len
+ ext_prop
->data_len
+ 14;
2876 ext_prop_name
= func
->ffs
->ms_os_descs_ext_prop_name_avail
;
2877 func
->ffs
->ms_os_descs_ext_prop_name_avail
+=
2880 ext_prop_data
= func
->ffs
->ms_os_descs_ext_prop_data_avail
;
2881 func
->ffs
->ms_os_descs_ext_prop_data_avail
+=
2883 memcpy(ext_prop_data
,
2884 usb_ext_prop_data_ptr(data
, ext_prop
->name_len
),
2885 ext_prop
->data_len
);
2886 /* unicode data reported to the host as "WCHAR"s */
2887 switch (ext_prop
->type
) {
2888 case USB_EXT_PROP_UNICODE
:
2889 case USB_EXT_PROP_UNICODE_ENV
:
2890 case USB_EXT_PROP_UNICODE_LINK
:
2891 case USB_EXT_PROP_UNICODE_MULTI
:
2892 ext_prop
->data_len
*= 2;
2895 ext_prop
->data
= ext_prop_data
;
2897 memcpy(ext_prop_name
, usb_ext_prop_name_ptr(data
),
2898 ext_prop
->name_len
);
2899 /* property name reported to the host as "WCHAR"s */
2900 ext_prop
->name_len
*= 2;
2901 ext_prop
->name
= ext_prop_name
;
2903 t
->os_desc
->ext_prop_len
+=
2904 ext_prop
->name_len
+ ext_prop
->data_len
+ 14;
2905 ++t
->os_desc
->ext_prop_count
;
2906 list_add_tail(&ext_prop
->entry
, &t
->os_desc
->ext_prop
);
2910 pr_vdebug("unknown descriptor: %d\n", type
);
2916 static inline struct f_fs_opts
*ffs_do_functionfs_bind(struct usb_function
*f
,
2917 struct usb_configuration
*c
)
2919 struct ffs_function
*func
= ffs_func_from_usb(f
);
2920 struct f_fs_opts
*ffs_opts
=
2921 container_of(f
->fi
, struct f_fs_opts
, func_inst
);
2927 * Legacy gadget triggers binding in functionfs_ready_callback,
2928 * which already uses locking; taking the same lock here would
2931 * Configfs-enabled gadgets however do need ffs_dev_lock.
2933 if (!ffs_opts
->no_configfs
)
2935 ret
= ffs_opts
->dev
->desc_ready
? 0 : -ENODEV
;
2936 func
->ffs
= ffs_opts
->dev
->ffs_data
;
2937 if (!ffs_opts
->no_configfs
)
2940 return ERR_PTR(ret
);
2943 func
->gadget
= c
->cdev
->gadget
;
2946 * in drivers/usb/gadget/configfs.c:configfs_composite_bind()
2947 * configurations are bound in sequence with list_for_each_entry,
2948 * in each configuration its functions are bound in sequence
2949 * with list_for_each_entry, so we assume no race condition
2950 * with regard to ffs_opts->bound access
2952 if (!ffs_opts
->refcnt
) {
2953 ret
= functionfs_bind(func
->ffs
, c
->cdev
);
2955 return ERR_PTR(ret
);
2958 func
->function
.strings
= func
->ffs
->stringtabs
;
2963 static int _ffs_func_bind(struct usb_configuration
*c
,
2964 struct usb_function
*f
)
2966 struct ffs_function
*func
= ffs_func_from_usb(f
);
2967 struct ffs_data
*ffs
= func
->ffs
;
2969 const int full
= !!func
->ffs
->fs_descs_count
;
2970 const int high
= gadget_is_dualspeed(func
->gadget
) &&
2971 func
->ffs
->hs_descs_count
;
2972 const int super
= gadget_is_superspeed(func
->gadget
) &&
2973 func
->ffs
->ss_descs_count
;
2975 int fs_len
, hs_len
, ss_len
, ret
, i
;
2976 struct ffs_ep
*eps_ptr
;
2978 /* Make it a single chunk, less management later on */
2980 vla_item_with_sz(d
, struct ffs_ep
, eps
, ffs
->eps_count
);
2981 vla_item_with_sz(d
, struct usb_descriptor_header
*, fs_descs
,
2982 full
? ffs
->fs_descs_count
+ 1 : 0);
2983 vla_item_with_sz(d
, struct usb_descriptor_header
*, hs_descs
,
2984 high
? ffs
->hs_descs_count
+ 1 : 0);
2985 vla_item_with_sz(d
, struct usb_descriptor_header
*, ss_descs
,
2986 super
? ffs
->ss_descs_count
+ 1 : 0);
2987 vla_item_with_sz(d
, short, inums
, ffs
->interfaces_count
);
2988 vla_item_with_sz(d
, struct usb_os_desc_table
, os_desc_table
,
2989 c
->cdev
->use_os_string
? ffs
->interfaces_count
: 0);
2990 vla_item_with_sz(d
, char[16], ext_compat
,
2991 c
->cdev
->use_os_string
? ffs
->interfaces_count
: 0);
2992 vla_item_with_sz(d
, struct usb_os_desc
, os_desc
,
2993 c
->cdev
->use_os_string
? ffs
->interfaces_count
: 0);
2994 vla_item_with_sz(d
, struct usb_os_desc_ext_prop
, ext_prop
,
2995 ffs
->ms_os_descs_ext_prop_count
);
2996 vla_item_with_sz(d
, char, ext_prop_name
,
2997 ffs
->ms_os_descs_ext_prop_name_len
);
2998 vla_item_with_sz(d
, char, ext_prop_data
,
2999 ffs
->ms_os_descs_ext_prop_data_len
);
3000 vla_item_with_sz(d
, char, raw_descs
, ffs
->raw_descs_length
);
3005 /* Has descriptors only for speeds gadget does not support */
3006 if (unlikely(!(full
| high
| super
)))
3009 /* Allocate a single chunk, less management later on */
3010 vlabuf
= kzalloc(vla_group_size(d
), GFP_KERNEL
);
3011 if (unlikely(!vlabuf
))
3014 ffs
->ms_os_descs_ext_prop_avail
= vla_ptr(vlabuf
, d
, ext_prop
);
3015 ffs
->ms_os_descs_ext_prop_name_avail
=
3016 vla_ptr(vlabuf
, d
, ext_prop_name
);
3017 ffs
->ms_os_descs_ext_prop_data_avail
=
3018 vla_ptr(vlabuf
, d
, ext_prop_data
);
3020 /* Copy descriptors */
3021 memcpy(vla_ptr(vlabuf
, d
, raw_descs
), ffs
->raw_descs
,
3022 ffs
->raw_descs_length
);
3024 memset(vla_ptr(vlabuf
, d
, inums
), 0xff, d_inums__sz
);
3025 eps_ptr
= vla_ptr(vlabuf
, d
, eps
);
3026 for (i
= 0; i
< ffs
->eps_count
; i
++)
3027 eps_ptr
[i
].num
= -1;
3030 * d_eps == vlabuf, func->eps used to kfree vlabuf later
3032 func
->eps
= vla_ptr(vlabuf
, d
, eps
);
3033 func
->interfaces_nums
= vla_ptr(vlabuf
, d
, inums
);
3036 * Go through all the endpoint descriptors and allocate
3037 * endpoints first, so that later we can rewrite the endpoint
3038 * numbers without worrying that it may be described later on.
3041 func
->function
.fs_descriptors
= vla_ptr(vlabuf
, d
, fs_descs
);
3042 fs_len
= ffs_do_descs(ffs
->fs_descs_count
,
3043 vla_ptr(vlabuf
, d
, raw_descs
),
3045 __ffs_func_bind_do_descs
, func
);
3046 if (unlikely(fs_len
< 0)) {
3055 func
->function
.hs_descriptors
= vla_ptr(vlabuf
, d
, hs_descs
);
3056 hs_len
= ffs_do_descs(ffs
->hs_descs_count
,
3057 vla_ptr(vlabuf
, d
, raw_descs
) + fs_len
,
3058 d_raw_descs__sz
- fs_len
,
3059 __ffs_func_bind_do_descs
, func
);
3060 if (unlikely(hs_len
< 0)) {
3068 if (likely(super
)) {
3069 func
->function
.ss_descriptors
= vla_ptr(vlabuf
, d
, ss_descs
);
3070 ss_len
= ffs_do_descs(ffs
->ss_descs_count
,
3071 vla_ptr(vlabuf
, d
, raw_descs
) + fs_len
+ hs_len
,
3072 d_raw_descs__sz
- fs_len
- hs_len
,
3073 __ffs_func_bind_do_descs
, func
);
3074 if (unlikely(ss_len
< 0)) {
3083 * Now handle interface numbers allocation and interface and
3084 * endpoint numbers rewriting. We can do that in one go
3087 ret
= ffs_do_descs(ffs
->fs_descs_count
+
3088 (high
? ffs
->hs_descs_count
: 0) +
3089 (super
? ffs
->ss_descs_count
: 0),
3090 vla_ptr(vlabuf
, d
, raw_descs
), d_raw_descs__sz
,
3091 __ffs_func_bind_do_nums
, func
);
3092 if (unlikely(ret
< 0))
3095 func
->function
.os_desc_table
= vla_ptr(vlabuf
, d
, os_desc_table
);
3096 if (c
->cdev
->use_os_string
) {
3097 for (i
= 0; i
< ffs
->interfaces_count
; ++i
) {
3098 struct usb_os_desc
*desc
;
3100 desc
= func
->function
.os_desc_table
[i
].os_desc
=
3101 vla_ptr(vlabuf
, d
, os_desc
) +
3102 i
* sizeof(struct usb_os_desc
);
3103 desc
->ext_compat_id
=
3104 vla_ptr(vlabuf
, d
, ext_compat
) + i
* 16;
3105 INIT_LIST_HEAD(&desc
->ext_prop
);
3107 ret
= ffs_do_os_descs(ffs
->ms_os_descs_count
,
3108 vla_ptr(vlabuf
, d
, raw_descs
) +
3109 fs_len
+ hs_len
+ ss_len
,
3110 d_raw_descs__sz
- fs_len
- hs_len
-
3112 __ffs_func_bind_do_os_desc
, func
);
3113 if (unlikely(ret
< 0))
3116 func
->function
.os_desc_n
=
3117 c
->cdev
->use_os_string
? ffs
->interfaces_count
: 0;
3119 /* And we're done */
3120 ffs_event_add(ffs
, FUNCTIONFS_BIND
);
3124 /* XXX Do we need to release all claimed endpoints here? */
3128 static int ffs_func_bind(struct usb_configuration
*c
,
3129 struct usb_function
*f
)
3131 struct f_fs_opts
*ffs_opts
= ffs_do_functionfs_bind(f
, c
);
3132 struct ffs_function
*func
= ffs_func_from_usb(f
);
3135 if (IS_ERR(ffs_opts
))
3136 return PTR_ERR(ffs_opts
);
3138 ret
= _ffs_func_bind(c
, f
);
3139 if (ret
&& !--ffs_opts
->refcnt
)
3140 functionfs_unbind(func
->ffs
);
3146 /* Other USB function hooks *************************************************/
3148 static void ffs_reset_work(struct work_struct
*work
)
3150 struct ffs_data
*ffs
= container_of(work
,
3151 struct ffs_data
, reset_work
);
3152 ffs_data_reset(ffs
);
3155 static int ffs_func_set_alt(struct usb_function
*f
,
3156 unsigned interface
, unsigned alt
)
3158 struct ffs_function
*func
= ffs_func_from_usb(f
);
3159 struct ffs_data
*ffs
= func
->ffs
;
3162 if (alt
!= (unsigned)-1) {
3163 intf
= ffs_func_revmap_intf(func
, interface
);
3164 if (unlikely(intf
< 0))
3169 ffs_func_eps_disable(ffs
->func
);
3171 if (ffs
->state
== FFS_DEACTIVATED
) {
3172 ffs
->state
= FFS_CLOSING
;
3173 INIT_WORK(&ffs
->reset_work
, ffs_reset_work
);
3174 schedule_work(&ffs
->reset_work
);
3178 if (ffs
->state
!= FFS_ACTIVE
)
3181 if (alt
== (unsigned)-1) {
3183 ffs_event_add(ffs
, FUNCTIONFS_DISABLE
);
3188 ret
= ffs_func_eps_enable(func
);
3189 if (likely(ret
>= 0))
3190 ffs_event_add(ffs
, FUNCTIONFS_ENABLE
);
3194 static void ffs_func_disable(struct usb_function
*f
)
3196 ffs_func_set_alt(f
, 0, (unsigned)-1);
3199 static int ffs_func_setup(struct usb_function
*f
,
3200 const struct usb_ctrlrequest
*creq
)
3202 struct ffs_function
*func
= ffs_func_from_usb(f
);
3203 struct ffs_data
*ffs
= func
->ffs
;
3204 unsigned long flags
;
3209 pr_vdebug("creq->bRequestType = %02x\n", creq
->bRequestType
);
3210 pr_vdebug("creq->bRequest = %02x\n", creq
->bRequest
);
3211 pr_vdebug("creq->wValue = %04x\n", le16_to_cpu(creq
->wValue
));
3212 pr_vdebug("creq->wIndex = %04x\n", le16_to_cpu(creq
->wIndex
));
3213 pr_vdebug("creq->wLength = %04x\n", le16_to_cpu(creq
->wLength
));
3216 * Most requests directed to interface go through here
3217 * (notable exceptions are set/get interface) so we need to
3218 * handle them. All other either handled by composite or
3219 * passed to usb_configuration->setup() (if one is set). No
3220 * matter, we will handle requests directed to endpoint here
3221 * as well (as it's straightforward). Other request recipient
3222 * types are only handled when the user flag FUNCTIONFS_ALL_CTRL_RECIP
3225 if (ffs
->state
!= FFS_ACTIVE
)
3228 switch (creq
->bRequestType
& USB_RECIP_MASK
) {
3229 case USB_RECIP_INTERFACE
:
3230 ret
= ffs_func_revmap_intf(func
, le16_to_cpu(creq
->wIndex
));
3231 if (unlikely(ret
< 0))
3235 case USB_RECIP_ENDPOINT
:
3236 ret
= ffs_func_revmap_ep(func
, le16_to_cpu(creq
->wIndex
));
3237 if (unlikely(ret
< 0))
3239 if (func
->ffs
->user_flags
& FUNCTIONFS_VIRTUAL_ADDR
)
3240 ret
= func
->ffs
->eps_addrmap
[ret
];
3244 if (func
->ffs
->user_flags
& FUNCTIONFS_ALL_CTRL_RECIP
)
3245 ret
= le16_to_cpu(creq
->wIndex
);
3250 spin_lock_irqsave(&ffs
->ev
.waitq
.lock
, flags
);
3251 ffs
->ev
.setup
= *creq
;
3252 ffs
->ev
.setup
.wIndex
= cpu_to_le16(ret
);
3253 __ffs_event_add(ffs
, FUNCTIONFS_SETUP
);
3254 spin_unlock_irqrestore(&ffs
->ev
.waitq
.lock
, flags
);
3259 static bool ffs_func_req_match(struct usb_function
*f
,
3260 const struct usb_ctrlrequest
*creq
,
3263 struct ffs_function
*func
= ffs_func_from_usb(f
);
3265 if (config0
&& !(func
->ffs
->user_flags
& FUNCTIONFS_CONFIG0_SETUP
))
3268 switch (creq
->bRequestType
& USB_RECIP_MASK
) {
3269 case USB_RECIP_INTERFACE
:
3270 return (ffs_func_revmap_intf(func
,
3271 le16_to_cpu(creq
->wIndex
)) >= 0);
3272 case USB_RECIP_ENDPOINT
:
3273 return (ffs_func_revmap_ep(func
,
3274 le16_to_cpu(creq
->wIndex
)) >= 0);
3276 return (bool) (func
->ffs
->user_flags
&
3277 FUNCTIONFS_ALL_CTRL_RECIP
);
3281 static void ffs_func_suspend(struct usb_function
*f
)
3284 ffs_event_add(ffs_func_from_usb(f
)->ffs
, FUNCTIONFS_SUSPEND
);
3287 static void ffs_func_resume(struct usb_function
*f
)
3290 ffs_event_add(ffs_func_from_usb(f
)->ffs
, FUNCTIONFS_RESUME
);
3294 /* Endpoint and interface numbers reverse mapping ***************************/
3296 static int ffs_func_revmap_ep(struct ffs_function
*func
, u8 num
)
3298 num
= func
->eps_revmap
[num
& USB_ENDPOINT_NUMBER_MASK
];
3299 return num
? num
: -EDOM
;
3302 static int ffs_func_revmap_intf(struct ffs_function
*func
, u8 intf
)
3304 short *nums
= func
->interfaces_nums
;
3305 unsigned count
= func
->ffs
->interfaces_count
;
3307 for (; count
; --count
, ++nums
) {
3308 if (*nums
>= 0 && *nums
== intf
)
3309 return nums
- func
->interfaces_nums
;
3316 /* Devices management *******************************************************/
3318 static LIST_HEAD(ffs_devices
);
3320 static struct ffs_dev
*_ffs_do_find_dev(const char *name
)
3322 struct ffs_dev
*dev
;
3327 list_for_each_entry(dev
, &ffs_devices
, entry
) {
3328 if (strcmp(dev
->name
, name
) == 0)
3336 * ffs_lock must be taken by the caller of this function
3338 static struct ffs_dev
*_ffs_get_single_dev(void)
3340 struct ffs_dev
*dev
;
3342 if (list_is_singular(&ffs_devices
)) {
3343 dev
= list_first_entry(&ffs_devices
, struct ffs_dev
, entry
);
3352 * ffs_lock must be taken by the caller of this function
3354 static struct ffs_dev
*_ffs_find_dev(const char *name
)
3356 struct ffs_dev
*dev
;
3358 dev
= _ffs_get_single_dev();
3362 return _ffs_do_find_dev(name
);
3365 /* Configfs support *********************************************************/
3367 static inline struct f_fs_opts
*to_ffs_opts(struct config_item
*item
)
3369 return container_of(to_config_group(item
), struct f_fs_opts
,
3373 static void ffs_attr_release(struct config_item
*item
)
3375 struct f_fs_opts
*opts
= to_ffs_opts(item
);
3377 usb_put_function_instance(&opts
->func_inst
);
3380 static struct configfs_item_operations ffs_item_ops
= {
3381 .release
= ffs_attr_release
,
3384 static const struct config_item_type ffs_func_type
= {
3385 .ct_item_ops
= &ffs_item_ops
,
3386 .ct_owner
= THIS_MODULE
,
3390 /* Function registration interface ******************************************/
3392 static void ffs_free_inst(struct usb_function_instance
*f
)
3394 struct f_fs_opts
*opts
;
3396 opts
= to_f_fs_opts(f
);
3398 _ffs_free_dev(opts
->dev
);
3403 static int ffs_set_inst_name(struct usb_function_instance
*fi
, const char *name
)
3405 if (strlen(name
) >= FIELD_SIZEOF(struct ffs_dev
, name
))
3406 return -ENAMETOOLONG
;
3407 return ffs_name_dev(to_f_fs_opts(fi
)->dev
, name
);
3410 static struct usb_function_instance
*ffs_alloc_inst(void)
3412 struct f_fs_opts
*opts
;
3413 struct ffs_dev
*dev
;
3415 opts
= kzalloc(sizeof(*opts
), GFP_KERNEL
);
3417 return ERR_PTR(-ENOMEM
);
3419 opts
->func_inst
.set_inst_name
= ffs_set_inst_name
;
3420 opts
->func_inst
.free_func_inst
= ffs_free_inst
;
3422 dev
= _ffs_alloc_dev();
3426 return ERR_CAST(dev
);
3431 config_group_init_type_name(&opts
->func_inst
.group
, "",
3433 return &opts
->func_inst
;
3436 static void ffs_free(struct usb_function
*f
)
3438 kfree(ffs_func_from_usb(f
));
3441 static void ffs_func_unbind(struct usb_configuration
*c
,
3442 struct usb_function
*f
)
3444 struct ffs_function
*func
= ffs_func_from_usb(f
);
3445 struct ffs_data
*ffs
= func
->ffs
;
3446 struct f_fs_opts
*opts
=
3447 container_of(f
->fi
, struct f_fs_opts
, func_inst
);
3448 struct ffs_ep
*ep
= func
->eps
;
3449 unsigned count
= ffs
->eps_count
;
3450 unsigned long flags
;
3453 if (ffs
->func
== func
) {
3454 ffs_func_eps_disable(func
);
3458 if (!--opts
->refcnt
)
3459 functionfs_unbind(ffs
);
3461 /* cleanup after autoconfig */
3462 spin_lock_irqsave(&func
->ffs
->eps_lock
, flags
);
3464 if (ep
->ep
&& ep
->req
)
3465 usb_ep_free_request(ep
->ep
, ep
->req
);
3469 spin_unlock_irqrestore(&func
->ffs
->eps_lock
, flags
);
3473 * eps, descriptors and interfaces_nums are allocated in the
3474 * same chunk so only one free is required.
3476 func
->function
.fs_descriptors
= NULL
;
3477 func
->function
.hs_descriptors
= NULL
;
3478 func
->function
.ss_descriptors
= NULL
;
3479 func
->interfaces_nums
= NULL
;
3481 ffs_event_add(ffs
, FUNCTIONFS_UNBIND
);
3484 static struct usb_function
*ffs_alloc(struct usb_function_instance
*fi
)
3486 struct ffs_function
*func
;
3490 func
= kzalloc(sizeof(*func
), GFP_KERNEL
);
3491 if (unlikely(!func
))
3492 return ERR_PTR(-ENOMEM
);
3494 func
->function
.name
= "Function FS Gadget";
3496 func
->function
.bind
= ffs_func_bind
;
3497 func
->function
.unbind
= ffs_func_unbind
;
3498 func
->function
.set_alt
= ffs_func_set_alt
;
3499 func
->function
.disable
= ffs_func_disable
;
3500 func
->function
.setup
= ffs_func_setup
;
3501 func
->function
.req_match
= ffs_func_req_match
;
3502 func
->function
.suspend
= ffs_func_suspend
;
3503 func
->function
.resume
= ffs_func_resume
;
3504 func
->function
.free_func
= ffs_free
;
3506 return &func
->function
;
3510 * ffs_lock must be taken by the caller of this function
3512 static struct ffs_dev
*_ffs_alloc_dev(void)
3514 struct ffs_dev
*dev
;
3517 if (_ffs_get_single_dev())
3518 return ERR_PTR(-EBUSY
);
3520 dev
= kzalloc(sizeof(*dev
), GFP_KERNEL
);
3522 return ERR_PTR(-ENOMEM
);
3524 if (list_empty(&ffs_devices
)) {
3525 ret
= functionfs_init();
3528 return ERR_PTR(ret
);
3532 list_add(&dev
->entry
, &ffs_devices
);
3537 int ffs_name_dev(struct ffs_dev
*dev
, const char *name
)
3539 struct ffs_dev
*existing
;
3544 existing
= _ffs_do_find_dev(name
);
3546 strlcpy(dev
->name
, name
, ARRAY_SIZE(dev
->name
));
3547 else if (existing
!= dev
)
3554 EXPORT_SYMBOL_GPL(ffs_name_dev
);
3556 int ffs_single_dev(struct ffs_dev
*dev
)
3563 if (!list_is_singular(&ffs_devices
))
3571 EXPORT_SYMBOL_GPL(ffs_single_dev
);
3574 * ffs_lock must be taken by the caller of this function
3576 static void _ffs_free_dev(struct ffs_dev
*dev
)
3578 list_del(&dev
->entry
);
3580 /* Clear the private_data pointer to stop incorrect dev access */
3582 dev
->ffs_data
->private_data
= NULL
;
3585 if (list_empty(&ffs_devices
))
3586 functionfs_cleanup();
3589 static void *ffs_acquire_dev(const char *dev_name
)
3591 struct ffs_dev
*ffs_dev
;
3596 ffs_dev
= _ffs_find_dev(dev_name
);
3598 ffs_dev
= ERR_PTR(-ENOENT
);
3599 else if (ffs_dev
->mounted
)
3600 ffs_dev
= ERR_PTR(-EBUSY
);
3601 else if (ffs_dev
->ffs_acquire_dev_callback
&&
3602 ffs_dev
->ffs_acquire_dev_callback(ffs_dev
))
3603 ffs_dev
= ERR_PTR(-ENOENT
);
3605 ffs_dev
->mounted
= true;
3611 static void ffs_release_dev(struct ffs_data
*ffs_data
)
3613 struct ffs_dev
*ffs_dev
;
3618 ffs_dev
= ffs_data
->private_data
;
3620 ffs_dev
->mounted
= false;
3622 if (ffs_dev
->ffs_release_dev_callback
)
3623 ffs_dev
->ffs_release_dev_callback(ffs_dev
);
3629 static int ffs_ready(struct ffs_data
*ffs
)
3631 struct ffs_dev
*ffs_obj
;
3637 ffs_obj
= ffs
->private_data
;
3642 if (WARN_ON(ffs_obj
->desc_ready
)) {
3647 ffs_obj
->desc_ready
= true;
3648 ffs_obj
->ffs_data
= ffs
;
3650 if (ffs_obj
->ffs_ready_callback
) {
3651 ret
= ffs_obj
->ffs_ready_callback(ffs
);
3656 set_bit(FFS_FL_CALL_CLOSED_CALLBACK
, &ffs
->flags
);
3662 static void ffs_closed(struct ffs_data
*ffs
)
3664 struct ffs_dev
*ffs_obj
;
3665 struct f_fs_opts
*opts
;
3666 struct config_item
*ci
;
3671 ffs_obj
= ffs
->private_data
;
3675 ffs_obj
->desc_ready
= false;
3676 ffs_obj
->ffs_data
= NULL
;
3678 if (test_and_clear_bit(FFS_FL_CALL_CLOSED_CALLBACK
, &ffs
->flags
) &&
3679 ffs_obj
->ffs_closed_callback
)
3680 ffs_obj
->ffs_closed_callback(ffs
);
3683 opts
= ffs_obj
->opts
;
3687 if (opts
->no_configfs
|| !opts
->func_inst
.group
.cg_item
.ci_parent
3688 || !kref_read(&opts
->func_inst
.group
.cg_item
.ci_kref
))
3691 ci
= opts
->func_inst
.group
.cg_item
.ci_parent
->ci_parent
;
3694 unregister_gadget_item(ci
);
3700 /* Misc helper functions ****************************************************/
3702 static int ffs_mutex_lock(struct mutex
*mutex
, unsigned nonblock
)
3705 ? likely(mutex_trylock(mutex
)) ? 0 : -EAGAIN
3706 : mutex_lock_interruptible(mutex
);
3709 static char *ffs_prepare_buffer(const char __user
*buf
, size_t len
)
3716 data
= kmalloc(len
, GFP_KERNEL
);
3717 if (unlikely(!data
))
3718 return ERR_PTR(-ENOMEM
);
3720 if (unlikely(copy_from_user(data
, buf
, len
))) {
3722 return ERR_PTR(-EFAULT
);
3725 pr_vdebug("Buffer from user space:\n");
3726 ffs_dump_mem("", data
, len
);
3731 DECLARE_USB_FUNCTION_INIT(ffs
, ffs_alloc_inst
, ffs_alloc
);
3732 MODULE_LICENSE("GPL");
3733 MODULE_AUTHOR("Michal Nazarewicz");