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 <linux/sched/signal.h>
27 #include <linux/uio.h>
28 #include <asm/unaligned.h>
30 #include <linux/usb/composite.h>
31 #include <linux/usb/functionfs.h>
33 #include <linux/aio.h>
34 #include <linux/mmu_context.h>
35 #include <linux/poll.h>
36 #include <linux/eventfd.h>
40 #include "u_os_desc.h"
43 #define FUNCTIONFS_MAGIC 0xa647361 /* Chosen by a honest dice roll ;) */
45 /* Reference counter handling */
46 static void ffs_data_get(struct ffs_data
*ffs
);
47 static void ffs_data_put(struct ffs_data
*ffs
);
48 /* Creates new ffs_data object. */
49 static struct ffs_data
*__must_check
ffs_data_new(void) __attribute__((malloc
));
51 /* Opened counter handling. */
52 static void ffs_data_opened(struct ffs_data
*ffs
);
53 static void ffs_data_closed(struct ffs_data
*ffs
);
55 /* Called with ffs->mutex held; take over ownership of data. */
56 static int __must_check
57 __ffs_data_got_descs(struct ffs_data
*ffs
, char *data
, size_t len
);
58 static int __must_check
59 __ffs_data_got_strings(struct ffs_data
*ffs
, char *data
, size_t len
);
62 /* The function structure ***************************************************/
67 struct usb_configuration
*conf
;
68 struct usb_gadget
*gadget
;
73 short *interfaces_nums
;
75 struct usb_function function
;
79 static struct ffs_function
*ffs_func_from_usb(struct usb_function
*f
)
81 return container_of(f
, struct ffs_function
, function
);
85 static inline enum ffs_setup_state
86 ffs_setup_state_clear_cancelled(struct ffs_data
*ffs
)
88 return (enum ffs_setup_state
)
89 cmpxchg(&ffs
->setup_state
, FFS_SETUP_CANCELLED
, FFS_NO_SETUP
);
93 static void ffs_func_eps_disable(struct ffs_function
*func
);
94 static int __must_check
ffs_func_eps_enable(struct ffs_function
*func
);
96 static int ffs_func_bind(struct usb_configuration
*,
97 struct usb_function
*);
98 static int ffs_func_set_alt(struct usb_function
*, unsigned, unsigned);
99 static void ffs_func_disable(struct usb_function
*);
100 static int ffs_func_setup(struct usb_function
*,
101 const struct usb_ctrlrequest
*);
102 static bool ffs_func_req_match(struct usb_function
*,
103 const struct usb_ctrlrequest
*,
105 static void ffs_func_suspend(struct usb_function
*);
106 static void ffs_func_resume(struct usb_function
*);
109 static int ffs_func_revmap_ep(struct ffs_function
*func
, u8 num
);
110 static int ffs_func_revmap_intf(struct ffs_function
*func
, u8 intf
);
113 /* The endpoints structures *************************************************/
116 struct usb_ep
*ep
; /* P: ffs->eps_lock */
117 struct usb_request
*req
; /* P: epfile->mutex */
119 /* [0]: full speed, [1]: high speed, [2]: super speed */
120 struct usb_endpoint_descriptor
*descs
[3];
124 int status
; /* P: epfile->mutex */
128 /* Protects ep->ep and ep->req. */
130 wait_queue_head_t wait
;
132 struct ffs_data
*ffs
;
133 struct ffs_ep
*ep
; /* P: ffs->eps_lock */
135 struct dentry
*dentry
;
138 * Buffer for holding data from partial reads which may happen since
139 * we’re rounding user read requests to a multiple of a max packet size.
141 * The pointer is initialised with NULL value and may be set by
142 * __ffs_epfile_read_data function to point to a temporary buffer.
144 * In normal operation, calls to __ffs_epfile_read_buffered will consume
145 * data from said buffer and eventually free it. Importantly, while the
146 * function is using the buffer, it sets the pointer to NULL. This is
147 * all right since __ffs_epfile_read_data and __ffs_epfile_read_buffered
148 * can never run concurrently (they are synchronised by epfile->mutex)
149 * so the latter will not assign a new value to the pointer.
151 * Meanwhile ffs_func_eps_disable frees the buffer (if the pointer is
152 * valid) and sets the pointer to READ_BUFFER_DROP value. This special
153 * value is crux of the synchronisation between ffs_func_eps_disable and
154 * __ffs_epfile_read_data.
156 * Once __ffs_epfile_read_data is about to finish it will try to set the
157 * pointer back to its old value (as described above), but seeing as the
158 * pointer is not-NULL (namely READ_BUFFER_DROP) it will instead free
161 * == State transitions ==
163 * • ptr == NULL: (initial state)
164 * ◦ __ffs_epfile_read_buffer_free: go to ptr == DROP
165 * ◦ __ffs_epfile_read_buffered: nop
166 * ◦ __ffs_epfile_read_data allocates temp buffer: go to ptr == buf
167 * ◦ reading finishes: n/a, not in ‘and reading’ state
169 * ◦ __ffs_epfile_read_buffer_free: nop
170 * ◦ __ffs_epfile_read_buffered: go to ptr == NULL
171 * ◦ __ffs_epfile_read_data allocates temp buffer: free buf, nop
172 * ◦ reading finishes: n/a, not in ‘and reading’ state
174 * ◦ __ffs_epfile_read_buffer_free: free buf, go to ptr == DROP
175 * ◦ __ffs_epfile_read_buffered: go to ptr == NULL and reading
176 * ◦ __ffs_epfile_read_data: n/a, __ffs_epfile_read_buffered
177 * is always called first
178 * ◦ reading finishes: n/a, not in ‘and reading’ state
179 * • ptr == NULL and reading:
180 * ◦ __ffs_epfile_read_buffer_free: go to ptr == DROP and reading
181 * ◦ __ffs_epfile_read_buffered: n/a, mutex is held
182 * ◦ __ffs_epfile_read_data: n/a, mutex is held
183 * ◦ reading finishes and …
184 * … all data read: free buf, go to ptr == NULL
185 * … otherwise: go to ptr == buf and reading
186 * • ptr == DROP and reading:
187 * ◦ __ffs_epfile_read_buffer_free: nop
188 * ◦ __ffs_epfile_read_buffered: n/a, mutex is held
189 * ◦ __ffs_epfile_read_data: n/a, mutex is held
190 * ◦ reading finishes: free buf, go to ptr == DROP
192 struct ffs_buffer
*read_buffer
;
193 #define READ_BUFFER_DROP ((struct ffs_buffer *)ERR_PTR(-ESHUTDOWN))
197 unsigned char in
; /* P: ffs->eps_lock */
198 unsigned char isoc
; /* P: ffs->eps_lock */
209 /* ffs_io_data structure ***************************************************/
216 struct iov_iter data
;
220 struct mm_struct
*mm
;
221 struct work_struct work
;
224 struct usb_request
*req
;
226 struct ffs_data
*ffs
;
229 struct ffs_desc_helper
{
230 struct ffs_data
*ffs
;
231 unsigned interfaces_count
;
235 static int __must_check
ffs_epfiles_create(struct ffs_data
*ffs
);
236 static void ffs_epfiles_destroy(struct ffs_epfile
*epfiles
, unsigned count
);
238 static struct dentry
*
239 ffs_sb_create_file(struct super_block
*sb
, const char *name
, void *data
,
240 const struct file_operations
*fops
);
242 /* Devices management *******************************************************/
244 DEFINE_MUTEX(ffs_lock
);
245 EXPORT_SYMBOL_GPL(ffs_lock
);
247 static struct ffs_dev
*_ffs_find_dev(const char *name
);
248 static struct ffs_dev
*_ffs_alloc_dev(void);
249 static void _ffs_free_dev(struct ffs_dev
*dev
);
250 static void *ffs_acquire_dev(const char *dev_name
);
251 static void ffs_release_dev(struct ffs_data
*ffs_data
);
252 static int ffs_ready(struct ffs_data
*ffs
);
253 static void ffs_closed(struct ffs_data
*ffs
);
255 /* Misc helper functions ****************************************************/
257 static int ffs_mutex_lock(struct mutex
*mutex
, unsigned nonblock
)
258 __attribute__((warn_unused_result
, nonnull
));
259 static char *ffs_prepare_buffer(const char __user
*buf
, size_t len
)
260 __attribute__((warn_unused_result
, nonnull
));
263 /* Control file aka ep0 *****************************************************/
265 static void ffs_ep0_complete(struct usb_ep
*ep
, struct usb_request
*req
)
267 struct ffs_data
*ffs
= req
->context
;
269 complete(&ffs
->ep0req_completion
);
272 static int __ffs_ep0_queue_wait(struct ffs_data
*ffs
, char *data
, size_t len
)
274 struct usb_request
*req
= ffs
->ep0req
;
277 req
->zero
= len
< le16_to_cpu(ffs
->ev
.setup
.wLength
);
279 spin_unlock_irq(&ffs
->ev
.waitq
.lock
);
285 * UDC layer requires to provide a buffer even for ZLP, but should
286 * not use it at all. Let's provide some poisoned pointer to catch
287 * possible bug in the driver.
289 if (req
->buf
== NULL
)
290 req
->buf
= (void *)0xDEADBABE;
292 reinit_completion(&ffs
->ep0req_completion
);
294 ret
= usb_ep_queue(ffs
->gadget
->ep0
, req
, GFP_ATOMIC
);
295 if (unlikely(ret
< 0))
298 ret
= wait_for_completion_interruptible(&ffs
->ep0req_completion
);
300 usb_ep_dequeue(ffs
->gadget
->ep0
, req
);
304 ffs
->setup_state
= FFS_NO_SETUP
;
305 return req
->status
? req
->status
: req
->actual
;
308 static int __ffs_ep0_stall(struct ffs_data
*ffs
)
310 if (ffs
->ev
.can_stall
) {
311 pr_vdebug("ep0 stall\n");
312 usb_ep_set_halt(ffs
->gadget
->ep0
);
313 ffs
->setup_state
= FFS_NO_SETUP
;
316 pr_debug("bogus ep0 stall!\n");
321 static ssize_t
ffs_ep0_write(struct file
*file
, const char __user
*buf
,
322 size_t len
, loff_t
*ptr
)
324 struct ffs_data
*ffs
= file
->private_data
;
330 /* Fast check if setup was canceled */
331 if (ffs_setup_state_clear_cancelled(ffs
) == FFS_SETUP_CANCELLED
)
335 ret
= ffs_mutex_lock(&ffs
->mutex
, file
->f_flags
& O_NONBLOCK
);
336 if (unlikely(ret
< 0))
340 switch (ffs
->state
) {
341 case FFS_READ_DESCRIPTORS
:
342 case FFS_READ_STRINGS
:
344 if (unlikely(len
< 16)) {
349 data
= ffs_prepare_buffer(buf
, len
);
356 if (ffs
->state
== FFS_READ_DESCRIPTORS
) {
357 pr_info("read descriptors\n");
358 ret
= __ffs_data_got_descs(ffs
, data
, len
);
359 if (unlikely(ret
< 0))
362 ffs
->state
= FFS_READ_STRINGS
;
365 pr_info("read strings\n");
366 ret
= __ffs_data_got_strings(ffs
, data
, len
);
367 if (unlikely(ret
< 0))
370 ret
= ffs_epfiles_create(ffs
);
372 ffs
->state
= FFS_CLOSING
;
376 ffs
->state
= FFS_ACTIVE
;
377 mutex_unlock(&ffs
->mutex
);
379 ret
= ffs_ready(ffs
);
380 if (unlikely(ret
< 0)) {
381 ffs
->state
= FFS_CLOSING
;
392 * We're called from user space, we can use _irq
393 * rather then _irqsave
395 spin_lock_irq(&ffs
->ev
.waitq
.lock
);
396 switch (ffs_setup_state_clear_cancelled(ffs
)) {
397 case FFS_SETUP_CANCELLED
:
405 case FFS_SETUP_PENDING
:
409 /* FFS_SETUP_PENDING */
410 if (!(ffs
->ev
.setup
.bRequestType
& USB_DIR_IN
)) {
411 spin_unlock_irq(&ffs
->ev
.waitq
.lock
);
412 ret
= __ffs_ep0_stall(ffs
);
416 /* FFS_SETUP_PENDING and not stall */
417 len
= min(len
, (size_t)le16_to_cpu(ffs
->ev
.setup
.wLength
));
419 spin_unlock_irq(&ffs
->ev
.waitq
.lock
);
421 data
= ffs_prepare_buffer(buf
, len
);
427 spin_lock_irq(&ffs
->ev
.waitq
.lock
);
430 * We are guaranteed to be still in FFS_ACTIVE state
431 * but the state of setup could have changed from
432 * FFS_SETUP_PENDING to FFS_SETUP_CANCELLED so we need
433 * to check for that. If that happened we copied data
434 * from user space in vain but it's unlikely.
436 * For sure we are not in FFS_NO_SETUP since this is
437 * the only place FFS_SETUP_PENDING -> FFS_NO_SETUP
438 * transition can be performed and it's protected by
441 if (ffs_setup_state_clear_cancelled(ffs
) ==
442 FFS_SETUP_CANCELLED
) {
445 spin_unlock_irq(&ffs
->ev
.waitq
.lock
);
447 /* unlocks spinlock */
448 ret
= __ffs_ep0_queue_wait(ffs
, data
, len
);
458 mutex_unlock(&ffs
->mutex
);
462 /* Called with ffs->ev.waitq.lock and ffs->mutex held, both released on exit. */
463 static ssize_t
__ffs_ep0_read_events(struct ffs_data
*ffs
, char __user
*buf
,
467 * n cannot be bigger than ffs->ev.count, which cannot be bigger than
468 * size of ffs->ev.types array (which is four) so that's how much space
471 struct usb_functionfs_event events
[ARRAY_SIZE(ffs
->ev
.types
)];
472 const size_t size
= n
* sizeof *events
;
475 memset(events
, 0, size
);
478 events
[i
].type
= ffs
->ev
.types
[i
];
479 if (events
[i
].type
== FUNCTIONFS_SETUP
) {
480 events
[i
].u
.setup
= ffs
->ev
.setup
;
481 ffs
->setup_state
= FFS_SETUP_PENDING
;
487 memmove(ffs
->ev
.types
, ffs
->ev
.types
+ n
,
488 ffs
->ev
.count
* sizeof *ffs
->ev
.types
);
490 spin_unlock_irq(&ffs
->ev
.waitq
.lock
);
491 mutex_unlock(&ffs
->mutex
);
493 return unlikely(copy_to_user(buf
, events
, size
)) ? -EFAULT
: size
;
496 static ssize_t
ffs_ep0_read(struct file
*file
, char __user
*buf
,
497 size_t len
, loff_t
*ptr
)
499 struct ffs_data
*ffs
= file
->private_data
;
506 /* Fast check if setup was canceled */
507 if (ffs_setup_state_clear_cancelled(ffs
) == FFS_SETUP_CANCELLED
)
511 ret
= ffs_mutex_lock(&ffs
->mutex
, file
->f_flags
& O_NONBLOCK
);
512 if (unlikely(ret
< 0))
516 if (ffs
->state
!= FFS_ACTIVE
) {
522 * We're called from user space, we can use _irq rather then
525 spin_lock_irq(&ffs
->ev
.waitq
.lock
);
527 switch (ffs_setup_state_clear_cancelled(ffs
)) {
528 case FFS_SETUP_CANCELLED
:
533 n
= len
/ sizeof(struct usb_functionfs_event
);
539 if ((file
->f_flags
& O_NONBLOCK
) && !ffs
->ev
.count
) {
544 if (wait_event_interruptible_exclusive_locked_irq(ffs
->ev
.waitq
,
550 return __ffs_ep0_read_events(ffs
, buf
,
551 min(n
, (size_t)ffs
->ev
.count
));
553 case FFS_SETUP_PENDING
:
554 if (ffs
->ev
.setup
.bRequestType
& USB_DIR_IN
) {
555 spin_unlock_irq(&ffs
->ev
.waitq
.lock
);
556 ret
= __ffs_ep0_stall(ffs
);
560 len
= min(len
, (size_t)le16_to_cpu(ffs
->ev
.setup
.wLength
));
562 spin_unlock_irq(&ffs
->ev
.waitq
.lock
);
565 data
= kmalloc(len
, GFP_KERNEL
);
566 if (unlikely(!data
)) {
572 spin_lock_irq(&ffs
->ev
.waitq
.lock
);
574 /* See ffs_ep0_write() */
575 if (ffs_setup_state_clear_cancelled(ffs
) ==
576 FFS_SETUP_CANCELLED
) {
581 /* unlocks spinlock */
582 ret
= __ffs_ep0_queue_wait(ffs
, data
, len
);
583 if (likely(ret
> 0) && unlikely(copy_to_user(buf
, data
, len
)))
592 spin_unlock_irq(&ffs
->ev
.waitq
.lock
);
594 mutex_unlock(&ffs
->mutex
);
599 static int ffs_ep0_open(struct inode
*inode
, struct file
*file
)
601 struct ffs_data
*ffs
= inode
->i_private
;
605 if (unlikely(ffs
->state
== FFS_CLOSING
))
608 file
->private_data
= ffs
;
609 ffs_data_opened(ffs
);
614 static int ffs_ep0_release(struct inode
*inode
, struct file
*file
)
616 struct ffs_data
*ffs
= file
->private_data
;
620 ffs_data_closed(ffs
);
625 static long ffs_ep0_ioctl(struct file
*file
, unsigned code
, unsigned long value
)
627 struct ffs_data
*ffs
= file
->private_data
;
628 struct usb_gadget
*gadget
= ffs
->gadget
;
633 if (code
== FUNCTIONFS_INTERFACE_REVMAP
) {
634 struct ffs_function
*func
= ffs
->func
;
635 ret
= func
? ffs_func_revmap_intf(func
, value
) : -ENODEV
;
636 } else if (gadget
&& gadget
->ops
->ioctl
) {
637 ret
= gadget
->ops
->ioctl(gadget
, code
, value
);
645 static unsigned int ffs_ep0_poll(struct file
*file
, poll_table
*wait
)
647 struct ffs_data
*ffs
= file
->private_data
;
648 unsigned int mask
= POLLWRNORM
;
651 poll_wait(file
, &ffs
->ev
.waitq
, wait
);
653 ret
= ffs_mutex_lock(&ffs
->mutex
, file
->f_flags
& O_NONBLOCK
);
654 if (unlikely(ret
< 0))
657 switch (ffs
->state
) {
658 case FFS_READ_DESCRIPTORS
:
659 case FFS_READ_STRINGS
:
664 switch (ffs
->setup_state
) {
670 case FFS_SETUP_PENDING
:
671 case FFS_SETUP_CANCELLED
:
672 mask
|= (POLLIN
| POLLOUT
);
677 case FFS_DEACTIVATED
:
681 mutex_unlock(&ffs
->mutex
);
686 static const struct file_operations ffs_ep0_operations
= {
689 .open
= ffs_ep0_open
,
690 .write
= ffs_ep0_write
,
691 .read
= ffs_ep0_read
,
692 .release
= ffs_ep0_release
,
693 .unlocked_ioctl
= ffs_ep0_ioctl
,
694 .poll
= ffs_ep0_poll
,
698 /* "Normal" endpoints operations ********************************************/
700 static void ffs_epfile_io_complete(struct usb_ep
*_ep
, struct usb_request
*req
)
703 if (likely(req
->context
)) {
704 struct ffs_ep
*ep
= _ep
->driver_data
;
705 ep
->status
= req
->status
? req
->status
: req
->actual
;
706 complete(req
->context
);
710 static ssize_t
ffs_copy_to_iter(void *data
, int data_len
, struct iov_iter
*iter
)
712 ssize_t ret
= copy_to_iter(data
, data_len
, iter
);
713 if (likely(ret
== data_len
))
716 if (unlikely(iov_iter_count(iter
)))
720 * Dear user space developer!
722 * TL;DR: To stop getting below error message in your kernel log, change
723 * user space code using functionfs to align read buffers to a max
726 * Some UDCs (e.g. dwc3) require request sizes to be a multiple of a max
727 * packet size. When unaligned buffer is passed to functionfs, it
728 * internally uses a larger, aligned buffer so that such UDCs are happy.
730 * Unfortunately, this means that host may send more data than was
731 * requested in read(2) system call. f_fs doesn’t know what to do with
732 * that excess data so it simply drops it.
734 * Was the buffer aligned in the first place, no such problem would
737 * Data may be dropped only in AIO reads. Synchronous reads are handled
738 * by splitting a request into multiple parts. This splitting may still
739 * be a problem though so it’s likely best to align the buffer
740 * regardless of it being AIO or not..
742 * This only affects OUT endpoints, i.e. reading data with a read(2),
743 * aio_read(2) etc. system calls. Writing data to an IN endpoint is not
746 pr_err("functionfs read size %d > requested size %zd, dropping excess data. "
747 "Align read buffer size to max packet size to avoid the problem.\n",
753 static void ffs_user_copy_worker(struct work_struct
*work
)
755 struct ffs_io_data
*io_data
= container_of(work
, struct ffs_io_data
,
757 int ret
= io_data
->req
->status
? io_data
->req
->status
:
758 io_data
->req
->actual
;
759 bool kiocb_has_eventfd
= io_data
->kiocb
->ki_flags
& IOCB_EVENTFD
;
761 if (io_data
->read
&& ret
> 0) {
763 ret
= ffs_copy_to_iter(io_data
->buf
, ret
, &io_data
->data
);
764 unuse_mm(io_data
->mm
);
767 io_data
->kiocb
->ki_complete(io_data
->kiocb
, ret
, ret
);
769 if (io_data
->ffs
->ffs_eventfd
&& !kiocb_has_eventfd
)
770 eventfd_signal(io_data
->ffs
->ffs_eventfd
, 1);
772 usb_ep_free_request(io_data
->ep
, io_data
->req
);
775 kfree(io_data
->to_free
);
780 static void ffs_epfile_async_io_complete(struct usb_ep
*_ep
,
781 struct usb_request
*req
)
783 struct ffs_io_data
*io_data
= req
->context
;
787 INIT_WORK(&io_data
->work
, ffs_user_copy_worker
);
788 schedule_work(&io_data
->work
);
791 static void __ffs_epfile_read_buffer_free(struct ffs_epfile
*epfile
)
794 * See comment in struct ffs_epfile for full read_buffer pointer
795 * synchronisation story.
797 struct ffs_buffer
*buf
= xchg(&epfile
->read_buffer
, READ_BUFFER_DROP
);
798 if (buf
&& buf
!= READ_BUFFER_DROP
)
802 /* Assumes epfile->mutex is held. */
803 static ssize_t
__ffs_epfile_read_buffered(struct ffs_epfile
*epfile
,
804 struct iov_iter
*iter
)
807 * Null out epfile->read_buffer so ffs_func_eps_disable does not free
808 * the buffer while we are using it. See comment in struct ffs_epfile
809 * for full read_buffer pointer synchronisation story.
811 struct ffs_buffer
*buf
= xchg(&epfile
->read_buffer
, NULL
);
813 if (!buf
|| buf
== READ_BUFFER_DROP
)
816 ret
= copy_to_iter(buf
->data
, buf
->length
, iter
);
817 if (buf
->length
== ret
) {
822 if (unlikely(iov_iter_count(iter
))) {
829 if (cmpxchg(&epfile
->read_buffer
, NULL
, buf
))
835 /* Assumes epfile->mutex is held. */
836 static ssize_t
__ffs_epfile_read_data(struct ffs_epfile
*epfile
,
837 void *data
, int data_len
,
838 struct iov_iter
*iter
)
840 struct ffs_buffer
*buf
;
842 ssize_t ret
= copy_to_iter(data
, data_len
, iter
);
843 if (likely(data_len
== ret
))
846 if (unlikely(iov_iter_count(iter
)))
849 /* See ffs_copy_to_iter for more context. */
850 pr_warn("functionfs read size %d > requested size %zd, splitting request into multiple reads.",
854 buf
= kmalloc(sizeof(*buf
) + data_len
, GFP_KERNEL
);
857 buf
->length
= data_len
;
858 buf
->data
= buf
->storage
;
859 memcpy(buf
->storage
, data
+ ret
, data_len
);
862 * At this point read_buffer is NULL or READ_BUFFER_DROP (if
863 * ffs_func_eps_disable has been called in the meanwhile). See comment
864 * in struct ffs_epfile for full read_buffer pointer synchronisation
867 if (unlikely(cmpxchg(&epfile
->read_buffer
, NULL
, buf
)))
873 static ssize_t
ffs_epfile_io(struct file
*file
, struct ffs_io_data
*io_data
)
875 struct ffs_epfile
*epfile
= file
->private_data
;
876 struct usb_request
*req
;
879 ssize_t ret
, data_len
= -EINVAL
;
882 /* Are we still active? */
883 if (WARN_ON(epfile
->ffs
->state
!= FFS_ACTIVE
))
886 /* Wait for endpoint to be enabled */
889 if (file
->f_flags
& O_NONBLOCK
)
892 ret
= wait_event_interruptible(epfile
->wait
, (ep
= epfile
->ep
));
898 halt
= (!io_data
->read
== !epfile
->in
);
899 if (halt
&& epfile
->isoc
)
902 /* We will be using request and read_buffer */
903 ret
= ffs_mutex_lock(&epfile
->mutex
, file
->f_flags
& O_NONBLOCK
);
907 /* Allocate & copy */
909 struct usb_gadget
*gadget
;
912 * Do we have buffered data from previous partial read? Check
913 * that for synchronous case only because we do not have
914 * facility to ‘wake up’ a pending asynchronous read and push
915 * buffered data to it which we would need to make things behave
918 if (!io_data
->aio
&& io_data
->read
) {
919 ret
= __ffs_epfile_read_buffered(epfile
, &io_data
->data
);
925 * if we _do_ wait above, the epfile->ffs->gadget might be NULL
926 * before the waiting completes, so do not assign to 'gadget'
929 gadget
= epfile
->ffs
->gadget
;
931 spin_lock_irq(&epfile
->ffs
->eps_lock
);
932 /* In the meantime, endpoint got disabled or changed. */
933 if (epfile
->ep
!= ep
) {
937 data_len
= iov_iter_count(&io_data
->data
);
939 * Controller may require buffer size to be aligned to
940 * maxpacketsize of an out endpoint.
943 data_len
= usb_ep_align_maybe(gadget
, ep
->ep
, data_len
);
944 spin_unlock_irq(&epfile
->ffs
->eps_lock
);
946 data
= kmalloc(data_len
, GFP_KERNEL
);
947 if (unlikely(!data
)) {
951 if (!io_data
->read
&&
952 !copy_from_iter_full(data
, data_len
, &io_data
->data
)) {
958 spin_lock_irq(&epfile
->ffs
->eps_lock
);
960 if (epfile
->ep
!= ep
) {
961 /* In the meantime, endpoint got disabled or changed. */
965 if (likely(epfile
->ep
== ep
) && !WARN_ON(!ep
->ep
))
966 usb_ep_set_halt(ep
->ep
);
968 } else if (unlikely(data_len
== -EINVAL
)) {
970 * Sanity Check: even though data_len can't be used
971 * uninitialized at the time I write this comment, some
972 * compilers complain about this situation.
973 * In order to keep the code clean from warnings, data_len is
974 * being initialized to -EINVAL during its declaration, which
975 * means we can't rely on compiler anymore to warn no future
976 * changes won't result in data_len being used uninitialized.
977 * For such reason, we're adding this redundant sanity check
980 WARN(1, "%s: data_len == -EINVAL\n", __func__
);
982 } else if (!io_data
->aio
) {
983 DECLARE_COMPLETION_ONSTACK(done
);
984 bool interrupted
= false;
988 req
->length
= data_len
;
990 req
->context
= &done
;
991 req
->complete
= ffs_epfile_io_complete
;
993 ret
= usb_ep_queue(ep
->ep
, req
, GFP_ATOMIC
);
994 if (unlikely(ret
< 0))
997 spin_unlock_irq(&epfile
->ffs
->eps_lock
);
999 if (unlikely(wait_for_completion_interruptible(&done
))) {
1001 * To avoid race condition with ffs_epfile_io_complete,
1002 * dequeue the request first then check
1003 * status. usb_ep_dequeue API should guarantee no race
1004 * condition with req->complete callback.
1006 usb_ep_dequeue(ep
->ep
, req
);
1007 interrupted
= ep
->status
< 0;
1012 else if (io_data
->read
&& ep
->status
> 0)
1013 ret
= __ffs_epfile_read_data(epfile
, data
, ep
->status
,
1018 } else if (!(req
= usb_ep_alloc_request(ep
->ep
, GFP_KERNEL
))) {
1022 req
->length
= data_len
;
1024 io_data
->buf
= data
;
1025 io_data
->ep
= ep
->ep
;
1027 io_data
->ffs
= epfile
->ffs
;
1029 req
->context
= io_data
;
1030 req
->complete
= ffs_epfile_async_io_complete
;
1032 ret
= usb_ep_queue(ep
->ep
, req
, GFP_ATOMIC
);
1033 if (unlikely(ret
)) {
1034 usb_ep_free_request(ep
->ep
, req
);
1040 * Do not kfree the buffer in this function. It will be freed
1041 * by ffs_user_copy_worker.
1047 spin_unlock_irq(&epfile
->ffs
->eps_lock
);
1049 mutex_unlock(&epfile
->mutex
);
1056 ffs_epfile_open(struct inode
*inode
, struct file
*file
)
1058 struct ffs_epfile
*epfile
= inode
->i_private
;
1062 if (WARN_ON(epfile
->ffs
->state
!= FFS_ACTIVE
))
1065 file
->private_data
= epfile
;
1066 ffs_data_opened(epfile
->ffs
);
1071 static int ffs_aio_cancel(struct kiocb
*kiocb
)
1073 struct ffs_io_data
*io_data
= kiocb
->private;
1074 struct ffs_epfile
*epfile
= kiocb
->ki_filp
->private_data
;
1079 spin_lock_irq(&epfile
->ffs
->eps_lock
);
1081 if (likely(io_data
&& io_data
->ep
&& io_data
->req
))
1082 value
= usb_ep_dequeue(io_data
->ep
, io_data
->req
);
1086 spin_unlock_irq(&epfile
->ffs
->eps_lock
);
1091 static ssize_t
ffs_epfile_write_iter(struct kiocb
*kiocb
, struct iov_iter
*from
)
1093 struct ffs_io_data io_data
, *p
= &io_data
;
1098 if (!is_sync_kiocb(kiocb
)) {
1099 p
= kmalloc(sizeof(io_data
), GFP_KERNEL
);
1110 p
->mm
= current
->mm
;
1115 kiocb_set_cancel_fn(kiocb
, ffs_aio_cancel
);
1117 res
= ffs_epfile_io(kiocb
->ki_filp
, p
);
1118 if (res
== -EIOCBQUEUED
)
1127 static ssize_t
ffs_epfile_read_iter(struct kiocb
*kiocb
, struct iov_iter
*to
)
1129 struct ffs_io_data io_data
, *p
= &io_data
;
1134 if (!is_sync_kiocb(kiocb
)) {
1135 p
= kmalloc(sizeof(io_data
), GFP_KERNEL
);
1146 p
->to_free
= dup_iter(&p
->data
, to
, GFP_KERNEL
);
1155 p
->mm
= current
->mm
;
1160 kiocb_set_cancel_fn(kiocb
, ffs_aio_cancel
);
1162 res
= ffs_epfile_io(kiocb
->ki_filp
, p
);
1163 if (res
== -EIOCBQUEUED
)
1176 ffs_epfile_release(struct inode
*inode
, struct file
*file
)
1178 struct ffs_epfile
*epfile
= inode
->i_private
;
1182 __ffs_epfile_read_buffer_free(epfile
);
1183 ffs_data_closed(epfile
->ffs
);
1188 static long ffs_epfile_ioctl(struct file
*file
, unsigned code
,
1189 unsigned long value
)
1191 struct ffs_epfile
*epfile
= file
->private_data
;
1196 if (WARN_ON(epfile
->ffs
->state
!= FFS_ACTIVE
))
1199 spin_lock_irq(&epfile
->ffs
->eps_lock
);
1200 if (likely(epfile
->ep
)) {
1202 case FUNCTIONFS_FIFO_STATUS
:
1203 ret
= usb_ep_fifo_status(epfile
->ep
->ep
);
1205 case FUNCTIONFS_FIFO_FLUSH
:
1206 usb_ep_fifo_flush(epfile
->ep
->ep
);
1209 case FUNCTIONFS_CLEAR_HALT
:
1210 ret
= usb_ep_clear_halt(epfile
->ep
->ep
);
1212 case FUNCTIONFS_ENDPOINT_REVMAP
:
1213 ret
= epfile
->ep
->num
;
1215 case FUNCTIONFS_ENDPOINT_DESC
:
1218 struct usb_endpoint_descriptor
*desc
;
1220 switch (epfile
->ffs
->gadget
->speed
) {
1221 case USB_SPEED_SUPER
:
1224 case USB_SPEED_HIGH
:
1230 desc
= epfile
->ep
->descs
[desc_idx
];
1232 spin_unlock_irq(&epfile
->ffs
->eps_lock
);
1233 ret
= copy_to_user((void *)value
, desc
, desc
->bLength
);
1244 spin_unlock_irq(&epfile
->ffs
->eps_lock
);
1249 static const struct file_operations ffs_epfile_operations
= {
1250 .llseek
= no_llseek
,
1252 .open
= ffs_epfile_open
,
1253 .write_iter
= ffs_epfile_write_iter
,
1254 .read_iter
= ffs_epfile_read_iter
,
1255 .release
= ffs_epfile_release
,
1256 .unlocked_ioctl
= ffs_epfile_ioctl
,
1260 /* File system and super block operations ***********************************/
1263 * Mounting the file system creates a controller file, used first for
1264 * function configuration then later for event monitoring.
1267 static struct inode
*__must_check
1268 ffs_sb_make_inode(struct super_block
*sb
, void *data
,
1269 const struct file_operations
*fops
,
1270 const struct inode_operations
*iops
,
1271 struct ffs_file_perms
*perms
)
1273 struct inode
*inode
;
1277 inode
= new_inode(sb
);
1279 if (likely(inode
)) {
1280 struct timespec ts
= current_time(inode
);
1282 inode
->i_ino
= get_next_ino();
1283 inode
->i_mode
= perms
->mode
;
1284 inode
->i_uid
= perms
->uid
;
1285 inode
->i_gid
= perms
->gid
;
1286 inode
->i_atime
= ts
;
1287 inode
->i_mtime
= ts
;
1288 inode
->i_ctime
= ts
;
1289 inode
->i_private
= data
;
1291 inode
->i_fop
= fops
;
1299 /* Create "regular" file */
1300 static struct dentry
*ffs_sb_create_file(struct super_block
*sb
,
1301 const char *name
, void *data
,
1302 const struct file_operations
*fops
)
1304 struct ffs_data
*ffs
= sb
->s_fs_info
;
1305 struct dentry
*dentry
;
1306 struct inode
*inode
;
1310 dentry
= d_alloc_name(sb
->s_root
, name
);
1311 if (unlikely(!dentry
))
1314 inode
= ffs_sb_make_inode(sb
, data
, fops
, NULL
, &ffs
->file_perms
);
1315 if (unlikely(!inode
)) {
1320 d_add(dentry
, inode
);
1325 static const struct super_operations ffs_sb_operations
= {
1326 .statfs
= simple_statfs
,
1327 .drop_inode
= generic_delete_inode
,
1330 struct ffs_sb_fill_data
{
1331 struct ffs_file_perms perms
;
1333 const char *dev_name
;
1335 struct ffs_data
*ffs_data
;
1338 static int ffs_sb_fill(struct super_block
*sb
, void *_data
, int silent
)
1340 struct ffs_sb_fill_data
*data
= _data
;
1341 struct inode
*inode
;
1342 struct ffs_data
*ffs
= data
->ffs_data
;
1347 data
->ffs_data
= NULL
;
1348 sb
->s_fs_info
= ffs
;
1349 sb
->s_blocksize
= PAGE_SIZE
;
1350 sb
->s_blocksize_bits
= PAGE_SHIFT
;
1351 sb
->s_magic
= FUNCTIONFS_MAGIC
;
1352 sb
->s_op
= &ffs_sb_operations
;
1353 sb
->s_time_gran
= 1;
1356 data
->perms
.mode
= data
->root_mode
;
1357 inode
= ffs_sb_make_inode(sb
, NULL
,
1358 &simple_dir_operations
,
1359 &simple_dir_inode_operations
,
1361 sb
->s_root
= d_make_root(inode
);
1362 if (unlikely(!sb
->s_root
))
1366 if (unlikely(!ffs_sb_create_file(sb
, "ep0", ffs
,
1367 &ffs_ep0_operations
)))
1373 static int ffs_fs_parse_opts(struct ffs_sb_fill_data
*data
, char *opts
)
1377 if (!opts
|| !*opts
)
1381 unsigned long value
;
1385 comma
= strchr(opts
, ',');
1390 eq
= strchr(opts
, '=');
1391 if (unlikely(!eq
)) {
1392 pr_err("'=' missing in %s\n", opts
);
1398 if (kstrtoul(eq
+ 1, 0, &value
)) {
1399 pr_err("%s: invalid value: %s\n", opts
, eq
+ 1);
1403 /* Interpret option */
1404 switch (eq
- opts
) {
1406 if (!memcmp(opts
, "no_disconnect", 13))
1407 data
->no_disconnect
= !!value
;
1412 if (!memcmp(opts
, "rmode", 5))
1413 data
->root_mode
= (value
& 0555) | S_IFDIR
;
1414 else if (!memcmp(opts
, "fmode", 5))
1415 data
->perms
.mode
= (value
& 0666) | S_IFREG
;
1421 if (!memcmp(opts
, "mode", 4)) {
1422 data
->root_mode
= (value
& 0555) | S_IFDIR
;
1423 data
->perms
.mode
= (value
& 0666) | S_IFREG
;
1430 if (!memcmp(opts
, "uid", 3)) {
1431 data
->perms
.uid
= make_kuid(current_user_ns(), value
);
1432 if (!uid_valid(data
->perms
.uid
)) {
1433 pr_err("%s: unmapped value: %lu\n", opts
, value
);
1436 } else if (!memcmp(opts
, "gid", 3)) {
1437 data
->perms
.gid
= make_kgid(current_user_ns(), value
);
1438 if (!gid_valid(data
->perms
.gid
)) {
1439 pr_err("%s: unmapped value: %lu\n", opts
, value
);
1449 pr_err("%s: invalid option\n", opts
);
1453 /* Next iteration */
1462 /* "mount -t functionfs dev_name /dev/function" ends up here */
1464 static struct dentry
*
1465 ffs_fs_mount(struct file_system_type
*t
, int flags
,
1466 const char *dev_name
, void *opts
)
1468 struct ffs_sb_fill_data data
= {
1470 .mode
= S_IFREG
| 0600,
1471 .uid
= GLOBAL_ROOT_UID
,
1472 .gid
= GLOBAL_ROOT_GID
,
1474 .root_mode
= S_IFDIR
| 0500,
1475 .no_disconnect
= false,
1480 struct ffs_data
*ffs
;
1484 ret
= ffs_fs_parse_opts(&data
, opts
);
1485 if (unlikely(ret
< 0))
1486 return ERR_PTR(ret
);
1488 ffs
= ffs_data_new();
1490 return ERR_PTR(-ENOMEM
);
1491 ffs
->file_perms
= data
.perms
;
1492 ffs
->no_disconnect
= data
.no_disconnect
;
1494 ffs
->dev_name
= kstrdup(dev_name
, GFP_KERNEL
);
1495 if (unlikely(!ffs
->dev_name
)) {
1497 return ERR_PTR(-ENOMEM
);
1500 ffs_dev
= ffs_acquire_dev(dev_name
);
1501 if (IS_ERR(ffs_dev
)) {
1503 return ERR_CAST(ffs_dev
);
1505 ffs
->private_data
= ffs_dev
;
1506 data
.ffs_data
= ffs
;
1508 rv
= mount_nodev(t
, flags
, &data
, ffs_sb_fill
);
1509 if (IS_ERR(rv
) && data
.ffs_data
) {
1510 ffs_release_dev(data
.ffs_data
);
1511 ffs_data_put(data
.ffs_data
);
1517 ffs_fs_kill_sb(struct super_block
*sb
)
1521 kill_litter_super(sb
);
1522 if (sb
->s_fs_info
) {
1523 ffs_release_dev(sb
->s_fs_info
);
1524 ffs_data_closed(sb
->s_fs_info
);
1525 ffs_data_put(sb
->s_fs_info
);
1529 static struct file_system_type ffs_fs_type
= {
1530 .owner
= THIS_MODULE
,
1531 .name
= "functionfs",
1532 .mount
= ffs_fs_mount
,
1533 .kill_sb
= ffs_fs_kill_sb
,
1535 MODULE_ALIAS_FS("functionfs");
1538 /* Driver's main init/cleanup functions *************************************/
1540 static int functionfs_init(void)
1546 ret
= register_filesystem(&ffs_fs_type
);
1548 pr_info("file system registered\n");
1550 pr_err("failed registering file system (%d)\n", ret
);
1555 static void functionfs_cleanup(void)
1559 pr_info("unloading\n");
1560 unregister_filesystem(&ffs_fs_type
);
1564 /* ffs_data and ffs_function construction and destruction code **************/
1566 static void ffs_data_clear(struct ffs_data
*ffs
);
1567 static void ffs_data_reset(struct ffs_data
*ffs
);
1569 static void ffs_data_get(struct ffs_data
*ffs
)
1573 refcount_inc(&ffs
->ref
);
1576 static void ffs_data_opened(struct ffs_data
*ffs
)
1580 refcount_inc(&ffs
->ref
);
1581 if (atomic_add_return(1, &ffs
->opened
) == 1 &&
1582 ffs
->state
== FFS_DEACTIVATED
) {
1583 ffs
->state
= FFS_CLOSING
;
1584 ffs_data_reset(ffs
);
1588 static void ffs_data_put(struct ffs_data
*ffs
)
1592 if (unlikely(refcount_dec_and_test(&ffs
->ref
))) {
1593 pr_info("%s(): freeing\n", __func__
);
1594 ffs_data_clear(ffs
);
1595 BUG_ON(waitqueue_active(&ffs
->ev
.waitq
) ||
1596 waitqueue_active(&ffs
->ep0req_completion
.wait
));
1597 kfree(ffs
->dev_name
);
1602 static void ffs_data_closed(struct ffs_data
*ffs
)
1606 if (atomic_dec_and_test(&ffs
->opened
)) {
1607 if (ffs
->no_disconnect
) {
1608 ffs
->state
= FFS_DEACTIVATED
;
1610 ffs_epfiles_destroy(ffs
->epfiles
,
1612 ffs
->epfiles
= NULL
;
1614 if (ffs
->setup_state
== FFS_SETUP_PENDING
)
1615 __ffs_ep0_stall(ffs
);
1617 ffs
->state
= FFS_CLOSING
;
1618 ffs_data_reset(ffs
);
1621 if (atomic_read(&ffs
->opened
) < 0) {
1622 ffs
->state
= FFS_CLOSING
;
1623 ffs_data_reset(ffs
);
1629 static struct ffs_data
*ffs_data_new(void)
1631 struct ffs_data
*ffs
= kzalloc(sizeof *ffs
, GFP_KERNEL
);
1637 refcount_set(&ffs
->ref
, 1);
1638 atomic_set(&ffs
->opened
, 0);
1639 ffs
->state
= FFS_READ_DESCRIPTORS
;
1640 mutex_init(&ffs
->mutex
);
1641 spin_lock_init(&ffs
->eps_lock
);
1642 init_waitqueue_head(&ffs
->ev
.waitq
);
1643 init_completion(&ffs
->ep0req_completion
);
1645 /* XXX REVISIT need to update it in some places, or do we? */
1646 ffs
->ev
.can_stall
= 1;
1651 static void ffs_data_clear(struct ffs_data
*ffs
)
1657 BUG_ON(ffs
->gadget
);
1660 ffs_epfiles_destroy(ffs
->epfiles
, ffs
->eps_count
);
1662 if (ffs
->ffs_eventfd
)
1663 eventfd_ctx_put(ffs
->ffs_eventfd
);
1665 kfree(ffs
->raw_descs_data
);
1666 kfree(ffs
->raw_strings
);
1667 kfree(ffs
->stringtabs
);
1670 static void ffs_data_reset(struct ffs_data
*ffs
)
1674 ffs_data_clear(ffs
);
1676 ffs
->epfiles
= NULL
;
1677 ffs
->raw_descs_data
= NULL
;
1678 ffs
->raw_descs
= NULL
;
1679 ffs
->raw_strings
= NULL
;
1680 ffs
->stringtabs
= NULL
;
1682 ffs
->raw_descs_length
= 0;
1683 ffs
->fs_descs_count
= 0;
1684 ffs
->hs_descs_count
= 0;
1685 ffs
->ss_descs_count
= 0;
1687 ffs
->strings_count
= 0;
1688 ffs
->interfaces_count
= 0;
1693 ffs
->state
= FFS_READ_DESCRIPTORS
;
1694 ffs
->setup_state
= FFS_NO_SETUP
;
1699 static int functionfs_bind(struct ffs_data
*ffs
, struct usb_composite_dev
*cdev
)
1701 struct usb_gadget_strings
**lang
;
1706 if (WARN_ON(ffs
->state
!= FFS_ACTIVE
1707 || test_and_set_bit(FFS_FL_BOUND
, &ffs
->flags
)))
1710 first_id
= usb_string_ids_n(cdev
, ffs
->strings_count
);
1711 if (unlikely(first_id
< 0))
1714 ffs
->ep0req
= usb_ep_alloc_request(cdev
->gadget
->ep0
, GFP_KERNEL
);
1715 if (unlikely(!ffs
->ep0req
))
1717 ffs
->ep0req
->complete
= ffs_ep0_complete
;
1718 ffs
->ep0req
->context
= ffs
;
1720 lang
= ffs
->stringtabs
;
1722 for (; *lang
; ++lang
) {
1723 struct usb_string
*str
= (*lang
)->strings
;
1725 for (; str
->s
; ++id
, ++str
)
1730 ffs
->gadget
= cdev
->gadget
;
1735 static void functionfs_unbind(struct ffs_data
*ffs
)
1739 if (!WARN_ON(!ffs
->gadget
)) {
1740 usb_ep_free_request(ffs
->gadget
->ep0
, ffs
->ep0req
);
1743 clear_bit(FFS_FL_BOUND
, &ffs
->flags
);
1748 static int ffs_epfiles_create(struct ffs_data
*ffs
)
1750 struct ffs_epfile
*epfile
, *epfiles
;
1755 count
= ffs
->eps_count
;
1756 epfiles
= kcalloc(count
, sizeof(*epfiles
), GFP_KERNEL
);
1761 for (i
= 1; i
<= count
; ++i
, ++epfile
) {
1763 mutex_init(&epfile
->mutex
);
1764 init_waitqueue_head(&epfile
->wait
);
1765 if (ffs
->user_flags
& FUNCTIONFS_VIRTUAL_ADDR
)
1766 sprintf(epfile
->name
, "ep%02x", ffs
->eps_addrmap
[i
]);
1768 sprintf(epfile
->name
, "ep%u", i
);
1769 epfile
->dentry
= ffs_sb_create_file(ffs
->sb
, epfile
->name
,
1771 &ffs_epfile_operations
);
1772 if (unlikely(!epfile
->dentry
)) {
1773 ffs_epfiles_destroy(epfiles
, i
- 1);
1778 ffs
->epfiles
= epfiles
;
1782 static void ffs_epfiles_destroy(struct ffs_epfile
*epfiles
, unsigned count
)
1784 struct ffs_epfile
*epfile
= epfiles
;
1788 for (; count
; --count
, ++epfile
) {
1789 BUG_ON(mutex_is_locked(&epfile
->mutex
) ||
1790 waitqueue_active(&epfile
->wait
));
1791 if (epfile
->dentry
) {
1792 d_delete(epfile
->dentry
);
1793 dput(epfile
->dentry
);
1794 epfile
->dentry
= NULL
;
1801 static void ffs_func_eps_disable(struct ffs_function
*func
)
1803 struct ffs_ep
*ep
= func
->eps
;
1804 struct ffs_epfile
*epfile
= func
->ffs
->epfiles
;
1805 unsigned count
= func
->ffs
->eps_count
;
1806 unsigned long flags
;
1808 spin_lock_irqsave(&func
->ffs
->eps_lock
, flags
);
1810 /* pending requests get nuked */
1812 usb_ep_disable(ep
->ep
);
1817 __ffs_epfile_read_buffer_free(epfile
);
1821 spin_unlock_irqrestore(&func
->ffs
->eps_lock
, flags
);
1824 static int ffs_func_eps_enable(struct ffs_function
*func
)
1826 struct ffs_data
*ffs
= func
->ffs
;
1827 struct ffs_ep
*ep
= func
->eps
;
1828 struct ffs_epfile
*epfile
= ffs
->epfiles
;
1829 unsigned count
= ffs
->eps_count
;
1830 unsigned long flags
;
1833 spin_lock_irqsave(&func
->ffs
->eps_lock
, flags
);
1835 struct usb_endpoint_descriptor
*ds
;
1836 struct usb_ss_ep_comp_descriptor
*comp_desc
= NULL
;
1837 int needs_comp_desc
= false;
1840 if (ffs
->gadget
->speed
== USB_SPEED_SUPER
) {
1842 needs_comp_desc
= true;
1843 } else if (ffs
->gadget
->speed
== USB_SPEED_HIGH
)
1848 /* fall-back to lower speed if desc missing for current speed */
1850 ds
= ep
->descs
[desc_idx
];
1851 } while (!ds
&& --desc_idx
>= 0);
1858 ep
->ep
->driver_data
= ep
;
1861 if (needs_comp_desc
) {
1862 comp_desc
= (struct usb_ss_ep_comp_descriptor
*)(ds
+
1863 USB_DT_ENDPOINT_SIZE
);
1864 ep
->ep
->maxburst
= comp_desc
->bMaxBurst
+ 1;
1865 ep
->ep
->comp_desc
= comp_desc
;
1868 ret
= usb_ep_enable(ep
->ep
);
1871 epfile
->in
= usb_endpoint_dir_in(ds
);
1872 epfile
->isoc
= usb_endpoint_xfer_isoc(ds
);
1877 wake_up(&epfile
->wait
);
1882 spin_unlock_irqrestore(&func
->ffs
->eps_lock
, flags
);
1888 /* Parsing and building descriptors and strings *****************************/
1891 * This validates if data pointed by data is a valid USB descriptor as
1892 * well as record how many interfaces, endpoints and strings are
1893 * required by given configuration. Returns address after the
1894 * descriptor or NULL if data is invalid.
1897 enum ffs_entity_type
{
1898 FFS_DESCRIPTOR
, FFS_INTERFACE
, FFS_STRING
, FFS_ENDPOINT
1901 enum ffs_os_desc_type
{
1902 FFS_OS_DESC
, FFS_OS_DESC_EXT_COMPAT
, FFS_OS_DESC_EXT_PROP
1905 typedef int (*ffs_entity_callback
)(enum ffs_entity_type entity
,
1907 struct usb_descriptor_header
*desc
,
1910 typedef int (*ffs_os_desc_callback
)(enum ffs_os_desc_type entity
,
1911 struct usb_os_desc_header
*h
, void *data
,
1912 unsigned len
, void *priv
);
1914 static int __must_check
ffs_do_single_desc(char *data
, unsigned len
,
1915 ffs_entity_callback entity
,
1918 struct usb_descriptor_header
*_ds
= (void *)data
;
1924 /* At least two bytes are required: length and type */
1926 pr_vdebug("descriptor too short\n");
1930 /* If we have at least as many bytes as the descriptor takes? */
1931 length
= _ds
->bLength
;
1933 pr_vdebug("descriptor longer then available data\n");
1937 #define __entity_check_INTERFACE(val) 1
1938 #define __entity_check_STRING(val) (val)
1939 #define __entity_check_ENDPOINT(val) ((val) & USB_ENDPOINT_NUMBER_MASK)
1940 #define __entity(type, val) do { \
1941 pr_vdebug("entity " #type "(%02x)\n", (val)); \
1942 if (unlikely(!__entity_check_ ##type(val))) { \
1943 pr_vdebug("invalid entity's value\n"); \
1946 ret = entity(FFS_ ##type, &val, _ds, priv); \
1947 if (unlikely(ret < 0)) { \
1948 pr_debug("entity " #type "(%02x); ret = %d\n", \
1954 /* Parse descriptor depending on type. */
1955 switch (_ds
->bDescriptorType
) {
1959 case USB_DT_DEVICE_QUALIFIER
:
1960 /* function can't have any of those */
1961 pr_vdebug("descriptor reserved for gadget: %d\n",
1962 _ds
->bDescriptorType
);
1965 case USB_DT_INTERFACE
: {
1966 struct usb_interface_descriptor
*ds
= (void *)_ds
;
1967 pr_vdebug("interface descriptor\n");
1968 if (length
!= sizeof *ds
)
1971 __entity(INTERFACE
, ds
->bInterfaceNumber
);
1973 __entity(STRING
, ds
->iInterface
);
1977 case USB_DT_ENDPOINT
: {
1978 struct usb_endpoint_descriptor
*ds
= (void *)_ds
;
1979 pr_vdebug("endpoint descriptor\n");
1980 if (length
!= USB_DT_ENDPOINT_SIZE
&&
1981 length
!= USB_DT_ENDPOINT_AUDIO_SIZE
)
1983 __entity(ENDPOINT
, ds
->bEndpointAddress
);
1988 pr_vdebug("hid descriptor\n");
1989 if (length
!= sizeof(struct hid_descriptor
))
1994 if (length
!= sizeof(struct usb_otg_descriptor
))
1998 case USB_DT_INTERFACE_ASSOCIATION
: {
1999 struct usb_interface_assoc_descriptor
*ds
= (void *)_ds
;
2000 pr_vdebug("interface association descriptor\n");
2001 if (length
!= sizeof *ds
)
2004 __entity(STRING
, ds
->iFunction
);
2008 case USB_DT_SS_ENDPOINT_COMP
:
2009 pr_vdebug("EP SS companion descriptor\n");
2010 if (length
!= sizeof(struct usb_ss_ep_comp_descriptor
))
2014 case USB_DT_OTHER_SPEED_CONFIG
:
2015 case USB_DT_INTERFACE_POWER
:
2017 case USB_DT_SECURITY
:
2018 case USB_DT_CS_RADIO_CONTROL
:
2020 pr_vdebug("unimplemented descriptor: %d\n", _ds
->bDescriptorType
);
2024 /* We should never be here */
2025 pr_vdebug("unknown descriptor: %d\n", _ds
->bDescriptorType
);
2029 pr_vdebug("invalid length: %d (descriptor %d)\n",
2030 _ds
->bLength
, _ds
->bDescriptorType
);
2035 #undef __entity_check_DESCRIPTOR
2036 #undef __entity_check_INTERFACE
2037 #undef __entity_check_STRING
2038 #undef __entity_check_ENDPOINT
2043 static int __must_check
ffs_do_descs(unsigned count
, char *data
, unsigned len
,
2044 ffs_entity_callback entity
, void *priv
)
2046 const unsigned _len
= len
;
2047 unsigned long num
= 0;
2057 /* Record "descriptor" entity */
2058 ret
= entity(FFS_DESCRIPTOR
, (u8
*)num
, (void *)data
, priv
);
2059 if (unlikely(ret
< 0)) {
2060 pr_debug("entity DESCRIPTOR(%02lx); ret = %d\n",
2068 ret
= ffs_do_single_desc(data
, len
, entity
, priv
);
2069 if (unlikely(ret
< 0)) {
2070 pr_debug("%s returns %d\n", __func__
, ret
);
2080 static int __ffs_data_do_entity(enum ffs_entity_type type
,
2081 u8
*valuep
, struct usb_descriptor_header
*desc
,
2084 struct ffs_desc_helper
*helper
= priv
;
2085 struct usb_endpoint_descriptor
*d
;
2090 case FFS_DESCRIPTOR
:
2095 * Interfaces are indexed from zero so if we
2096 * encountered interface "n" then there are at least
2099 if (*valuep
>= helper
->interfaces_count
)
2100 helper
->interfaces_count
= *valuep
+ 1;
2105 * Strings are indexed from 1 (0 is reserved
2106 * for languages list)
2108 if (*valuep
> helper
->ffs
->strings_count
)
2109 helper
->ffs
->strings_count
= *valuep
;
2114 helper
->eps_count
++;
2115 if (helper
->eps_count
>= FFS_MAX_EPS_COUNT
)
2117 /* Check if descriptors for any speed were already parsed */
2118 if (!helper
->ffs
->eps_count
&& !helper
->ffs
->interfaces_count
)
2119 helper
->ffs
->eps_addrmap
[helper
->eps_count
] =
2120 d
->bEndpointAddress
;
2121 else if (helper
->ffs
->eps_addrmap
[helper
->eps_count
] !=
2122 d
->bEndpointAddress
)
2130 static int __ffs_do_os_desc_header(enum ffs_os_desc_type
*next_type
,
2131 struct usb_os_desc_header
*desc
)
2133 u16 bcd_version
= le16_to_cpu(desc
->bcdVersion
);
2134 u16 w_index
= le16_to_cpu(desc
->wIndex
);
2136 if (bcd_version
!= 1) {
2137 pr_vdebug("unsupported os descriptors version: %d",
2143 *next_type
= FFS_OS_DESC_EXT_COMPAT
;
2146 *next_type
= FFS_OS_DESC_EXT_PROP
;
2149 pr_vdebug("unsupported os descriptor type: %d", w_index
);
2153 return sizeof(*desc
);
2157 * Process all extended compatibility/extended property descriptors
2158 * of a feature descriptor
2160 static int __must_check
ffs_do_single_os_desc(char *data
, unsigned len
,
2161 enum ffs_os_desc_type type
,
2163 ffs_os_desc_callback entity
,
2165 struct usb_os_desc_header
*h
)
2168 const unsigned _len
= len
;
2172 /* loop over all ext compat/ext prop descriptors */
2173 while (feature_count
--) {
2174 ret
= entity(type
, h
, data
, len
, priv
);
2175 if (unlikely(ret
< 0)) {
2176 pr_debug("bad OS descriptor, type: %d\n", type
);
2185 /* Process a number of complete Feature Descriptors (Ext Compat or Ext Prop) */
2186 static int __must_check
ffs_do_os_descs(unsigned count
,
2187 char *data
, unsigned len
,
2188 ffs_os_desc_callback entity
, void *priv
)
2190 const unsigned _len
= len
;
2191 unsigned long num
= 0;
2195 for (num
= 0; num
< count
; ++num
) {
2197 enum ffs_os_desc_type type
;
2199 struct usb_os_desc_header
*desc
= (void *)data
;
2201 if (len
< sizeof(*desc
))
2205 * Record "descriptor" entity.
2206 * Process dwLength, bcdVersion, wIndex, get b/wCount.
2207 * Move the data pointer to the beginning of extended
2208 * compatibilities proper or extended properties proper
2209 * portions of the data
2211 if (le32_to_cpu(desc
->dwLength
) > len
)
2214 ret
= __ffs_do_os_desc_header(&type
, desc
);
2215 if (unlikely(ret
< 0)) {
2216 pr_debug("entity OS_DESCRIPTOR(%02lx); ret = %d\n",
2221 * 16-bit hex "?? 00" Little Endian looks like 8-bit hex "??"
2223 feature_count
= le16_to_cpu(desc
->wCount
);
2224 if (type
== FFS_OS_DESC_EXT_COMPAT
&&
2225 (feature_count
> 255 || desc
->Reserved
))
2231 * Process all function/property descriptors
2232 * of this Feature Descriptor
2234 ret
= ffs_do_single_os_desc(data
, len
, type
,
2235 feature_count
, entity
, priv
, desc
);
2236 if (unlikely(ret
< 0)) {
2237 pr_debug("%s returns %d\n", __func__
, ret
);
2248 * Validate contents of the buffer from userspace related to OS descriptors.
2250 static int __ffs_data_do_os_desc(enum ffs_os_desc_type type
,
2251 struct usb_os_desc_header
*h
, void *data
,
2252 unsigned len
, void *priv
)
2254 struct ffs_data
*ffs
= priv
;
2260 case FFS_OS_DESC_EXT_COMPAT
: {
2261 struct usb_ext_compat_desc
*d
= data
;
2264 if (len
< sizeof(*d
) ||
2265 d
->bFirstInterfaceNumber
>= ffs
->interfaces_count
||
2268 for (i
= 0; i
< ARRAY_SIZE(d
->Reserved2
); ++i
)
2269 if (d
->Reserved2
[i
])
2272 length
= sizeof(struct usb_ext_compat_desc
);
2275 case FFS_OS_DESC_EXT_PROP
: {
2276 struct usb_ext_prop_desc
*d
= data
;
2280 if (len
< sizeof(*d
) || h
->interface
>= ffs
->interfaces_count
)
2282 length
= le32_to_cpu(d
->dwSize
);
2285 type
= le32_to_cpu(d
->dwPropertyDataType
);
2286 if (type
< USB_EXT_PROP_UNICODE
||
2287 type
> USB_EXT_PROP_UNICODE_MULTI
) {
2288 pr_vdebug("unsupported os descriptor property type: %d",
2292 pnl
= le16_to_cpu(d
->wPropertyNameLength
);
2293 if (length
< 14 + pnl
) {
2294 pr_vdebug("invalid os descriptor length: %d pnl:%d (descriptor %d)\n",
2298 pdl
= le32_to_cpu(*(u32
*)((u8
*)data
+ 10 + pnl
));
2299 if (length
!= 14 + pnl
+ pdl
) {
2300 pr_vdebug("invalid os descriptor length: %d pnl:%d pdl:%d (descriptor %d)\n",
2301 length
, pnl
, pdl
, type
);
2304 ++ffs
->ms_os_descs_ext_prop_count
;
2305 /* property name reported to the host as "WCHAR"s */
2306 ffs
->ms_os_descs_ext_prop_name_len
+= pnl
* 2;
2307 ffs
->ms_os_descs_ext_prop_data_len
+= pdl
;
2311 pr_vdebug("unknown descriptor: %d\n", type
);
2317 static int __ffs_data_got_descs(struct ffs_data
*ffs
,
2318 char *const _data
, size_t len
)
2320 char *data
= _data
, *raw_descs
;
2321 unsigned os_descs_count
= 0, counts
[3], flags
;
2322 int ret
= -EINVAL
, i
;
2323 struct ffs_desc_helper helper
;
2327 if (get_unaligned_le32(data
+ 4) != len
)
2330 switch (get_unaligned_le32(data
)) {
2331 case FUNCTIONFS_DESCRIPTORS_MAGIC
:
2332 flags
= FUNCTIONFS_HAS_FS_DESC
| FUNCTIONFS_HAS_HS_DESC
;
2336 case FUNCTIONFS_DESCRIPTORS_MAGIC_V2
:
2337 flags
= get_unaligned_le32(data
+ 8);
2338 ffs
->user_flags
= flags
;
2339 if (flags
& ~(FUNCTIONFS_HAS_FS_DESC
|
2340 FUNCTIONFS_HAS_HS_DESC
|
2341 FUNCTIONFS_HAS_SS_DESC
|
2342 FUNCTIONFS_HAS_MS_OS_DESC
|
2343 FUNCTIONFS_VIRTUAL_ADDR
|
2344 FUNCTIONFS_EVENTFD
|
2345 FUNCTIONFS_ALL_CTRL_RECIP
|
2346 FUNCTIONFS_CONFIG0_SETUP
)) {
2357 if (flags
& FUNCTIONFS_EVENTFD
) {
2361 eventfd_ctx_fdget((int)get_unaligned_le32(data
));
2362 if (IS_ERR(ffs
->ffs_eventfd
)) {
2363 ret
= PTR_ERR(ffs
->ffs_eventfd
);
2364 ffs
->ffs_eventfd
= NULL
;
2371 /* Read fs_count, hs_count and ss_count (if present) */
2372 for (i
= 0; i
< 3; ++i
) {
2373 if (!(flags
& (1 << i
))) {
2375 } else if (len
< 4) {
2378 counts
[i
] = get_unaligned_le32(data
);
2383 if (flags
& (1 << i
)) {
2387 os_descs_count
= get_unaligned_le32(data
);
2392 /* Read descriptors */
2395 for (i
= 0; i
< 3; ++i
) {
2398 helper
.interfaces_count
= 0;
2399 helper
.eps_count
= 0;
2400 ret
= ffs_do_descs(counts
[i
], data
, len
,
2401 __ffs_data_do_entity
, &helper
);
2404 if (!ffs
->eps_count
&& !ffs
->interfaces_count
) {
2405 ffs
->eps_count
= helper
.eps_count
;
2406 ffs
->interfaces_count
= helper
.interfaces_count
;
2408 if (ffs
->eps_count
!= helper
.eps_count
) {
2412 if (ffs
->interfaces_count
!= helper
.interfaces_count
) {
2420 if (os_descs_count
) {
2421 ret
= ffs_do_os_descs(os_descs_count
, data
, len
,
2422 __ffs_data_do_os_desc
, ffs
);
2429 if (raw_descs
== data
|| len
) {
2434 ffs
->raw_descs_data
= _data
;
2435 ffs
->raw_descs
= raw_descs
;
2436 ffs
->raw_descs_length
= data
- raw_descs
;
2437 ffs
->fs_descs_count
= counts
[0];
2438 ffs
->hs_descs_count
= counts
[1];
2439 ffs
->ss_descs_count
= counts
[2];
2440 ffs
->ms_os_descs_count
= os_descs_count
;
2449 static int __ffs_data_got_strings(struct ffs_data
*ffs
,
2450 char *const _data
, size_t len
)
2452 u32 str_count
, needed_count
, lang_count
;
2453 struct usb_gadget_strings
**stringtabs
, *t
;
2454 const char *data
= _data
;
2455 struct usb_string
*s
;
2459 if (unlikely(len
< 16 ||
2460 get_unaligned_le32(data
) != FUNCTIONFS_STRINGS_MAGIC
||
2461 get_unaligned_le32(data
+ 4) != len
))
2463 str_count
= get_unaligned_le32(data
+ 8);
2464 lang_count
= get_unaligned_le32(data
+ 12);
2466 /* if one is zero the other must be zero */
2467 if (unlikely(!str_count
!= !lang_count
))
2470 /* Do we have at least as many strings as descriptors need? */
2471 needed_count
= ffs
->strings_count
;
2472 if (unlikely(str_count
< needed_count
))
2476 * If we don't need any strings just return and free all
2479 if (!needed_count
) {
2484 /* Allocate everything in one chunk so there's less maintenance. */
2488 vla_item(d
, struct usb_gadget_strings
*, stringtabs
,
2490 vla_item(d
, struct usb_gadget_strings
, stringtab
, lang_count
);
2491 vla_item(d
, struct usb_string
, strings
,
2492 lang_count
*(needed_count
+1));
2494 char *vlabuf
= kmalloc(vla_group_size(d
), GFP_KERNEL
);
2496 if (unlikely(!vlabuf
)) {
2501 /* Initialize the VLA pointers */
2502 stringtabs
= vla_ptr(vlabuf
, d
, stringtabs
);
2503 t
= vla_ptr(vlabuf
, d
, stringtab
);
2506 *stringtabs
++ = t
++;
2510 /* stringtabs = vlabuf = d_stringtabs for later kfree */
2511 stringtabs
= vla_ptr(vlabuf
, d
, stringtabs
);
2512 t
= vla_ptr(vlabuf
, d
, stringtab
);
2513 s
= vla_ptr(vlabuf
, d
, strings
);
2516 /* For each language */
2520 do { /* lang_count > 0 so we can use do-while */
2521 unsigned needed
= needed_count
;
2523 if (unlikely(len
< 3))
2525 t
->language
= get_unaligned_le16(data
);
2532 /* For each string */
2533 do { /* str_count > 0 so we can use do-while */
2534 size_t length
= strnlen(data
, len
);
2536 if (unlikely(length
== len
))
2540 * User may provide more strings then we need,
2541 * if that's the case we simply ignore the
2544 if (likely(needed
)) {
2546 * s->id will be set while adding
2547 * function to configuration so for
2548 * now just leave garbage here.
2557 } while (--str_count
);
2559 s
->id
= 0; /* terminator */
2563 } while (--lang_count
);
2565 /* Some garbage left? */
2570 ffs
->stringtabs
= stringtabs
;
2571 ffs
->raw_strings
= _data
;
2583 /* Events handling and management *******************************************/
2585 static void __ffs_event_add(struct ffs_data
*ffs
,
2586 enum usb_functionfs_event_type type
)
2588 enum usb_functionfs_event_type rem_type1
, rem_type2
= type
;
2592 * Abort any unhandled setup
2594 * We do not need to worry about some cmpxchg() changing value
2595 * of ffs->setup_state without holding the lock because when
2596 * state is FFS_SETUP_PENDING cmpxchg() in several places in
2597 * the source does nothing.
2599 if (ffs
->setup_state
== FFS_SETUP_PENDING
)
2600 ffs
->setup_state
= FFS_SETUP_CANCELLED
;
2603 * Logic of this function guarantees that there are at most four pending
2604 * evens on ffs->ev.types queue. This is important because the queue
2605 * has space for four elements only and __ffs_ep0_read_events function
2606 * depends on that limit as well. If more event types are added, those
2607 * limits have to be revisited or guaranteed to still hold.
2610 case FUNCTIONFS_RESUME
:
2611 rem_type2
= FUNCTIONFS_SUSPEND
;
2613 case FUNCTIONFS_SUSPEND
:
2614 case FUNCTIONFS_SETUP
:
2616 /* Discard all similar events */
2619 case FUNCTIONFS_BIND
:
2620 case FUNCTIONFS_UNBIND
:
2621 case FUNCTIONFS_DISABLE
:
2622 case FUNCTIONFS_ENABLE
:
2623 /* Discard everything other then power management. */
2624 rem_type1
= FUNCTIONFS_SUSPEND
;
2625 rem_type2
= FUNCTIONFS_RESUME
;
2630 WARN(1, "%d: unknown event, this should not happen\n", type
);
2635 u8
*ev
= ffs
->ev
.types
, *out
= ev
;
2636 unsigned n
= ffs
->ev
.count
;
2637 for (; n
; --n
, ++ev
)
2638 if ((*ev
== rem_type1
|| *ev
== rem_type2
) == neg
)
2641 pr_vdebug("purging event %d\n", *ev
);
2642 ffs
->ev
.count
= out
- ffs
->ev
.types
;
2645 pr_vdebug("adding event %d\n", type
);
2646 ffs
->ev
.types
[ffs
->ev
.count
++] = type
;
2647 wake_up_locked(&ffs
->ev
.waitq
);
2648 if (ffs
->ffs_eventfd
)
2649 eventfd_signal(ffs
->ffs_eventfd
, 1);
2652 static void ffs_event_add(struct ffs_data
*ffs
,
2653 enum usb_functionfs_event_type type
)
2655 unsigned long flags
;
2656 spin_lock_irqsave(&ffs
->ev
.waitq
.lock
, flags
);
2657 __ffs_event_add(ffs
, type
);
2658 spin_unlock_irqrestore(&ffs
->ev
.waitq
.lock
, flags
);
2661 /* Bind/unbind USB function hooks *******************************************/
2663 static int ffs_ep_addr2idx(struct ffs_data
*ffs
, u8 endpoint_address
)
2667 for (i
= 1; i
< ARRAY_SIZE(ffs
->eps_addrmap
); ++i
)
2668 if (ffs
->eps_addrmap
[i
] == endpoint_address
)
2673 static int __ffs_func_bind_do_descs(enum ffs_entity_type type
, u8
*valuep
,
2674 struct usb_descriptor_header
*desc
,
2677 struct usb_endpoint_descriptor
*ds
= (void *)desc
;
2678 struct ffs_function
*func
= priv
;
2679 struct ffs_ep
*ffs_ep
;
2680 unsigned ep_desc_id
;
2682 static const char *speed_names
[] = { "full", "high", "super" };
2684 if (type
!= FFS_DESCRIPTOR
)
2688 * If ss_descriptors is not NULL, we are reading super speed
2689 * descriptors; if hs_descriptors is not NULL, we are reading high
2690 * speed descriptors; otherwise, we are reading full speed
2693 if (func
->function
.ss_descriptors
) {
2695 func
->function
.ss_descriptors
[(long)valuep
] = desc
;
2696 } else if (func
->function
.hs_descriptors
) {
2698 func
->function
.hs_descriptors
[(long)valuep
] = desc
;
2701 func
->function
.fs_descriptors
[(long)valuep
] = desc
;
2704 if (!desc
|| desc
->bDescriptorType
!= USB_DT_ENDPOINT
)
2707 idx
= ffs_ep_addr2idx(func
->ffs
, ds
->bEndpointAddress
) - 1;
2711 ffs_ep
= func
->eps
+ idx
;
2713 if (unlikely(ffs_ep
->descs
[ep_desc_id
])) {
2714 pr_err("two %sspeed descriptors for EP %d\n",
2715 speed_names
[ep_desc_id
],
2716 ds
->bEndpointAddress
& USB_ENDPOINT_NUMBER_MASK
);
2719 ffs_ep
->descs
[ep_desc_id
] = ds
;
2721 ffs_dump_mem(": Original ep desc", ds
, ds
->bLength
);
2723 ds
->bEndpointAddress
= ffs_ep
->descs
[0]->bEndpointAddress
;
2724 if (!ds
->wMaxPacketSize
)
2725 ds
->wMaxPacketSize
= ffs_ep
->descs
[0]->wMaxPacketSize
;
2727 struct usb_request
*req
;
2729 u8 bEndpointAddress
;
2732 * We back up bEndpointAddress because autoconfig overwrites
2733 * it with physical endpoint address.
2735 bEndpointAddress
= ds
->bEndpointAddress
;
2736 pr_vdebug("autoconfig\n");
2737 ep
= usb_ep_autoconfig(func
->gadget
, ds
);
2740 ep
->driver_data
= func
->eps
+ idx
;
2742 req
= usb_ep_alloc_request(ep
, GFP_KERNEL
);
2748 func
->eps_revmap
[ds
->bEndpointAddress
&
2749 USB_ENDPOINT_NUMBER_MASK
] = idx
+ 1;
2751 * If we use virtual address mapping, we restore
2752 * original bEndpointAddress value.
2754 if (func
->ffs
->user_flags
& FUNCTIONFS_VIRTUAL_ADDR
)
2755 ds
->bEndpointAddress
= bEndpointAddress
;
2757 ffs_dump_mem(": Rewritten ep desc", ds
, ds
->bLength
);
2762 static int __ffs_func_bind_do_nums(enum ffs_entity_type type
, u8
*valuep
,
2763 struct usb_descriptor_header
*desc
,
2766 struct ffs_function
*func
= priv
;
2772 case FFS_DESCRIPTOR
:
2773 /* Handled in previous pass by __ffs_func_bind_do_descs() */
2778 if (func
->interfaces_nums
[idx
] < 0) {
2779 int id
= usb_interface_id(func
->conf
, &func
->function
);
2780 if (unlikely(id
< 0))
2782 func
->interfaces_nums
[idx
] = id
;
2784 newValue
= func
->interfaces_nums
[idx
];
2788 /* String' IDs are allocated when fsf_data is bound to cdev */
2789 newValue
= func
->ffs
->stringtabs
[0]->strings
[*valuep
- 1].id
;
2794 * USB_DT_ENDPOINT are handled in
2795 * __ffs_func_bind_do_descs().
2797 if (desc
->bDescriptorType
== USB_DT_ENDPOINT
)
2800 idx
= (*valuep
& USB_ENDPOINT_NUMBER_MASK
) - 1;
2801 if (unlikely(!func
->eps
[idx
].ep
))
2805 struct usb_endpoint_descriptor
**descs
;
2806 descs
= func
->eps
[idx
].descs
;
2807 newValue
= descs
[descs
[0] ? 0 : 1]->bEndpointAddress
;
2812 pr_vdebug("%02x -> %02x\n", *valuep
, newValue
);
2817 static int __ffs_func_bind_do_os_desc(enum ffs_os_desc_type type
,
2818 struct usb_os_desc_header
*h
, void *data
,
2819 unsigned len
, void *priv
)
2821 struct ffs_function
*func
= priv
;
2825 case FFS_OS_DESC_EXT_COMPAT
: {
2826 struct usb_ext_compat_desc
*desc
= data
;
2827 struct usb_os_desc_table
*t
;
2829 t
= &func
->function
.os_desc_table
[desc
->bFirstInterfaceNumber
];
2830 t
->if_id
= func
->interfaces_nums
[desc
->bFirstInterfaceNumber
];
2831 memcpy(t
->os_desc
->ext_compat_id
, &desc
->CompatibleID
,
2832 ARRAY_SIZE(desc
->CompatibleID
) +
2833 ARRAY_SIZE(desc
->SubCompatibleID
));
2834 length
= sizeof(*desc
);
2837 case FFS_OS_DESC_EXT_PROP
: {
2838 struct usb_ext_prop_desc
*desc
= data
;
2839 struct usb_os_desc_table
*t
;
2840 struct usb_os_desc_ext_prop
*ext_prop
;
2841 char *ext_prop_name
;
2842 char *ext_prop_data
;
2844 t
= &func
->function
.os_desc_table
[h
->interface
];
2845 t
->if_id
= func
->interfaces_nums
[h
->interface
];
2847 ext_prop
= func
->ffs
->ms_os_descs_ext_prop_avail
;
2848 func
->ffs
->ms_os_descs_ext_prop_avail
+= sizeof(*ext_prop
);
2850 ext_prop
->type
= le32_to_cpu(desc
->dwPropertyDataType
);
2851 ext_prop
->name_len
= le16_to_cpu(desc
->wPropertyNameLength
);
2852 ext_prop
->data_len
= le32_to_cpu(*(u32
*)
2853 usb_ext_prop_data_len_ptr(data
, ext_prop
->name_len
));
2854 length
= ext_prop
->name_len
+ ext_prop
->data_len
+ 14;
2856 ext_prop_name
= func
->ffs
->ms_os_descs_ext_prop_name_avail
;
2857 func
->ffs
->ms_os_descs_ext_prop_name_avail
+=
2860 ext_prop_data
= func
->ffs
->ms_os_descs_ext_prop_data_avail
;
2861 func
->ffs
->ms_os_descs_ext_prop_data_avail
+=
2863 memcpy(ext_prop_data
,
2864 usb_ext_prop_data_ptr(data
, ext_prop
->name_len
),
2865 ext_prop
->data_len
);
2866 /* unicode data reported to the host as "WCHAR"s */
2867 switch (ext_prop
->type
) {
2868 case USB_EXT_PROP_UNICODE
:
2869 case USB_EXT_PROP_UNICODE_ENV
:
2870 case USB_EXT_PROP_UNICODE_LINK
:
2871 case USB_EXT_PROP_UNICODE_MULTI
:
2872 ext_prop
->data_len
*= 2;
2875 ext_prop
->data
= ext_prop_data
;
2877 memcpy(ext_prop_name
, usb_ext_prop_name_ptr(data
),
2878 ext_prop
->name_len
);
2879 /* property name reported to the host as "WCHAR"s */
2880 ext_prop
->name_len
*= 2;
2881 ext_prop
->name
= ext_prop_name
;
2883 t
->os_desc
->ext_prop_len
+=
2884 ext_prop
->name_len
+ ext_prop
->data_len
+ 14;
2885 ++t
->os_desc
->ext_prop_count
;
2886 list_add_tail(&ext_prop
->entry
, &t
->os_desc
->ext_prop
);
2890 pr_vdebug("unknown descriptor: %d\n", type
);
2896 static inline struct f_fs_opts
*ffs_do_functionfs_bind(struct usb_function
*f
,
2897 struct usb_configuration
*c
)
2899 struct ffs_function
*func
= ffs_func_from_usb(f
);
2900 struct f_fs_opts
*ffs_opts
=
2901 container_of(f
->fi
, struct f_fs_opts
, func_inst
);
2907 * Legacy gadget triggers binding in functionfs_ready_callback,
2908 * which already uses locking; taking the same lock here would
2911 * Configfs-enabled gadgets however do need ffs_dev_lock.
2913 if (!ffs_opts
->no_configfs
)
2915 ret
= ffs_opts
->dev
->desc_ready
? 0 : -ENODEV
;
2916 func
->ffs
= ffs_opts
->dev
->ffs_data
;
2917 if (!ffs_opts
->no_configfs
)
2920 return ERR_PTR(ret
);
2923 func
->gadget
= c
->cdev
->gadget
;
2926 * in drivers/usb/gadget/configfs.c:configfs_composite_bind()
2927 * configurations are bound in sequence with list_for_each_entry,
2928 * in each configuration its functions are bound in sequence
2929 * with list_for_each_entry, so we assume no race condition
2930 * with regard to ffs_opts->bound access
2932 if (!ffs_opts
->refcnt
) {
2933 ret
= functionfs_bind(func
->ffs
, c
->cdev
);
2935 return ERR_PTR(ret
);
2938 func
->function
.strings
= func
->ffs
->stringtabs
;
2943 static int _ffs_func_bind(struct usb_configuration
*c
,
2944 struct usb_function
*f
)
2946 struct ffs_function
*func
= ffs_func_from_usb(f
);
2947 struct ffs_data
*ffs
= func
->ffs
;
2949 const int full
= !!func
->ffs
->fs_descs_count
;
2950 const int high
= gadget_is_dualspeed(func
->gadget
) &&
2951 func
->ffs
->hs_descs_count
;
2952 const int super
= gadget_is_superspeed(func
->gadget
) &&
2953 func
->ffs
->ss_descs_count
;
2955 int fs_len
, hs_len
, ss_len
, ret
, i
;
2956 struct ffs_ep
*eps_ptr
;
2958 /* Make it a single chunk, less management later on */
2960 vla_item_with_sz(d
, struct ffs_ep
, eps
, ffs
->eps_count
);
2961 vla_item_with_sz(d
, struct usb_descriptor_header
*, fs_descs
,
2962 full
? ffs
->fs_descs_count
+ 1 : 0);
2963 vla_item_with_sz(d
, struct usb_descriptor_header
*, hs_descs
,
2964 high
? ffs
->hs_descs_count
+ 1 : 0);
2965 vla_item_with_sz(d
, struct usb_descriptor_header
*, ss_descs
,
2966 super
? ffs
->ss_descs_count
+ 1 : 0);
2967 vla_item_with_sz(d
, short, inums
, ffs
->interfaces_count
);
2968 vla_item_with_sz(d
, struct usb_os_desc_table
, os_desc_table
,
2969 c
->cdev
->use_os_string
? ffs
->interfaces_count
: 0);
2970 vla_item_with_sz(d
, char[16], ext_compat
,
2971 c
->cdev
->use_os_string
? ffs
->interfaces_count
: 0);
2972 vla_item_with_sz(d
, struct usb_os_desc
, os_desc
,
2973 c
->cdev
->use_os_string
? ffs
->interfaces_count
: 0);
2974 vla_item_with_sz(d
, struct usb_os_desc_ext_prop
, ext_prop
,
2975 ffs
->ms_os_descs_ext_prop_count
);
2976 vla_item_with_sz(d
, char, ext_prop_name
,
2977 ffs
->ms_os_descs_ext_prop_name_len
);
2978 vla_item_with_sz(d
, char, ext_prop_data
,
2979 ffs
->ms_os_descs_ext_prop_data_len
);
2980 vla_item_with_sz(d
, char, raw_descs
, ffs
->raw_descs_length
);
2985 /* Has descriptors only for speeds gadget does not support */
2986 if (unlikely(!(full
| high
| super
)))
2989 /* Allocate a single chunk, less management later on */
2990 vlabuf
= kzalloc(vla_group_size(d
), GFP_KERNEL
);
2991 if (unlikely(!vlabuf
))
2994 ffs
->ms_os_descs_ext_prop_avail
= vla_ptr(vlabuf
, d
, ext_prop
);
2995 ffs
->ms_os_descs_ext_prop_name_avail
=
2996 vla_ptr(vlabuf
, d
, ext_prop_name
);
2997 ffs
->ms_os_descs_ext_prop_data_avail
=
2998 vla_ptr(vlabuf
, d
, ext_prop_data
);
3000 /* Copy descriptors */
3001 memcpy(vla_ptr(vlabuf
, d
, raw_descs
), ffs
->raw_descs
,
3002 ffs
->raw_descs_length
);
3004 memset(vla_ptr(vlabuf
, d
, inums
), 0xff, d_inums__sz
);
3005 eps_ptr
= vla_ptr(vlabuf
, d
, eps
);
3006 for (i
= 0; i
< ffs
->eps_count
; i
++)
3007 eps_ptr
[i
].num
= -1;
3010 * d_eps == vlabuf, func->eps used to kfree vlabuf later
3012 func
->eps
= vla_ptr(vlabuf
, d
, eps
);
3013 func
->interfaces_nums
= vla_ptr(vlabuf
, d
, inums
);
3016 * Go through all the endpoint descriptors and allocate
3017 * endpoints first, so that later we can rewrite the endpoint
3018 * numbers without worrying that it may be described later on.
3021 func
->function
.fs_descriptors
= vla_ptr(vlabuf
, d
, fs_descs
);
3022 fs_len
= ffs_do_descs(ffs
->fs_descs_count
,
3023 vla_ptr(vlabuf
, d
, raw_descs
),
3025 __ffs_func_bind_do_descs
, func
);
3026 if (unlikely(fs_len
< 0)) {
3035 func
->function
.hs_descriptors
= vla_ptr(vlabuf
, d
, hs_descs
);
3036 hs_len
= ffs_do_descs(ffs
->hs_descs_count
,
3037 vla_ptr(vlabuf
, d
, raw_descs
) + fs_len
,
3038 d_raw_descs__sz
- fs_len
,
3039 __ffs_func_bind_do_descs
, func
);
3040 if (unlikely(hs_len
< 0)) {
3048 if (likely(super
)) {
3049 func
->function
.ss_descriptors
= vla_ptr(vlabuf
, d
, ss_descs
);
3050 ss_len
= ffs_do_descs(ffs
->ss_descs_count
,
3051 vla_ptr(vlabuf
, d
, raw_descs
) + fs_len
+ hs_len
,
3052 d_raw_descs__sz
- fs_len
- hs_len
,
3053 __ffs_func_bind_do_descs
, func
);
3054 if (unlikely(ss_len
< 0)) {
3063 * Now handle interface numbers allocation and interface and
3064 * endpoint numbers rewriting. We can do that in one go
3067 ret
= ffs_do_descs(ffs
->fs_descs_count
+
3068 (high
? ffs
->hs_descs_count
: 0) +
3069 (super
? ffs
->ss_descs_count
: 0),
3070 vla_ptr(vlabuf
, d
, raw_descs
), d_raw_descs__sz
,
3071 __ffs_func_bind_do_nums
, func
);
3072 if (unlikely(ret
< 0))
3075 func
->function
.os_desc_table
= vla_ptr(vlabuf
, d
, os_desc_table
);
3076 if (c
->cdev
->use_os_string
) {
3077 for (i
= 0; i
< ffs
->interfaces_count
; ++i
) {
3078 struct usb_os_desc
*desc
;
3080 desc
= func
->function
.os_desc_table
[i
].os_desc
=
3081 vla_ptr(vlabuf
, d
, os_desc
) +
3082 i
* sizeof(struct usb_os_desc
);
3083 desc
->ext_compat_id
=
3084 vla_ptr(vlabuf
, d
, ext_compat
) + i
* 16;
3085 INIT_LIST_HEAD(&desc
->ext_prop
);
3087 ret
= ffs_do_os_descs(ffs
->ms_os_descs_count
,
3088 vla_ptr(vlabuf
, d
, raw_descs
) +
3089 fs_len
+ hs_len
+ ss_len
,
3090 d_raw_descs__sz
- fs_len
- hs_len
-
3092 __ffs_func_bind_do_os_desc
, func
);
3093 if (unlikely(ret
< 0))
3096 func
->function
.os_desc_n
=
3097 c
->cdev
->use_os_string
? ffs
->interfaces_count
: 0;
3099 /* And we're done */
3100 ffs_event_add(ffs
, FUNCTIONFS_BIND
);
3104 /* XXX Do we need to release all claimed endpoints here? */
3108 static int ffs_func_bind(struct usb_configuration
*c
,
3109 struct usb_function
*f
)
3111 struct f_fs_opts
*ffs_opts
= ffs_do_functionfs_bind(f
, c
);
3112 struct ffs_function
*func
= ffs_func_from_usb(f
);
3115 if (IS_ERR(ffs_opts
))
3116 return PTR_ERR(ffs_opts
);
3118 ret
= _ffs_func_bind(c
, f
);
3119 if (ret
&& !--ffs_opts
->refcnt
)
3120 functionfs_unbind(func
->ffs
);
3126 /* Other USB function hooks *************************************************/
3128 static void ffs_reset_work(struct work_struct
*work
)
3130 struct ffs_data
*ffs
= container_of(work
,
3131 struct ffs_data
, reset_work
);
3132 ffs_data_reset(ffs
);
3135 static int ffs_func_set_alt(struct usb_function
*f
,
3136 unsigned interface
, unsigned alt
)
3138 struct ffs_function
*func
= ffs_func_from_usb(f
);
3139 struct ffs_data
*ffs
= func
->ffs
;
3142 if (alt
!= (unsigned)-1) {
3143 intf
= ffs_func_revmap_intf(func
, interface
);
3144 if (unlikely(intf
< 0))
3149 ffs_func_eps_disable(ffs
->func
);
3151 if (ffs
->state
== FFS_DEACTIVATED
) {
3152 ffs
->state
= FFS_CLOSING
;
3153 INIT_WORK(&ffs
->reset_work
, ffs_reset_work
);
3154 schedule_work(&ffs
->reset_work
);
3158 if (ffs
->state
!= FFS_ACTIVE
)
3161 if (alt
== (unsigned)-1) {
3163 ffs_event_add(ffs
, FUNCTIONFS_DISABLE
);
3168 ret
= ffs_func_eps_enable(func
);
3169 if (likely(ret
>= 0))
3170 ffs_event_add(ffs
, FUNCTIONFS_ENABLE
);
3174 static void ffs_func_disable(struct usb_function
*f
)
3176 ffs_func_set_alt(f
, 0, (unsigned)-1);
3179 static int ffs_func_setup(struct usb_function
*f
,
3180 const struct usb_ctrlrequest
*creq
)
3182 struct ffs_function
*func
= ffs_func_from_usb(f
);
3183 struct ffs_data
*ffs
= func
->ffs
;
3184 unsigned long flags
;
3189 pr_vdebug("creq->bRequestType = %02x\n", creq
->bRequestType
);
3190 pr_vdebug("creq->bRequest = %02x\n", creq
->bRequest
);
3191 pr_vdebug("creq->wValue = %04x\n", le16_to_cpu(creq
->wValue
));
3192 pr_vdebug("creq->wIndex = %04x\n", le16_to_cpu(creq
->wIndex
));
3193 pr_vdebug("creq->wLength = %04x\n", le16_to_cpu(creq
->wLength
));
3196 * Most requests directed to interface go through here
3197 * (notable exceptions are set/get interface) so we need to
3198 * handle them. All other either handled by composite or
3199 * passed to usb_configuration->setup() (if one is set). No
3200 * matter, we will handle requests directed to endpoint here
3201 * as well (as it's straightforward). Other request recipient
3202 * types are only handled when the user flag FUNCTIONFS_ALL_CTRL_RECIP
3205 if (ffs
->state
!= FFS_ACTIVE
)
3208 switch (creq
->bRequestType
& USB_RECIP_MASK
) {
3209 case USB_RECIP_INTERFACE
:
3210 ret
= ffs_func_revmap_intf(func
, le16_to_cpu(creq
->wIndex
));
3211 if (unlikely(ret
< 0))
3215 case USB_RECIP_ENDPOINT
:
3216 ret
= ffs_func_revmap_ep(func
, le16_to_cpu(creq
->wIndex
));
3217 if (unlikely(ret
< 0))
3219 if (func
->ffs
->user_flags
& FUNCTIONFS_VIRTUAL_ADDR
)
3220 ret
= func
->ffs
->eps_addrmap
[ret
];
3224 if (func
->ffs
->user_flags
& FUNCTIONFS_ALL_CTRL_RECIP
)
3225 ret
= le16_to_cpu(creq
->wIndex
);
3230 spin_lock_irqsave(&ffs
->ev
.waitq
.lock
, flags
);
3231 ffs
->ev
.setup
= *creq
;
3232 ffs
->ev
.setup
.wIndex
= cpu_to_le16(ret
);
3233 __ffs_event_add(ffs
, FUNCTIONFS_SETUP
);
3234 spin_unlock_irqrestore(&ffs
->ev
.waitq
.lock
, flags
);
3239 static bool ffs_func_req_match(struct usb_function
*f
,
3240 const struct usb_ctrlrequest
*creq
,
3243 struct ffs_function
*func
= ffs_func_from_usb(f
);
3245 if (config0
&& !(func
->ffs
->user_flags
& FUNCTIONFS_CONFIG0_SETUP
))
3248 switch (creq
->bRequestType
& USB_RECIP_MASK
) {
3249 case USB_RECIP_INTERFACE
:
3250 return (ffs_func_revmap_intf(func
,
3251 le16_to_cpu(creq
->wIndex
)) >= 0);
3252 case USB_RECIP_ENDPOINT
:
3253 return (ffs_func_revmap_ep(func
,
3254 le16_to_cpu(creq
->wIndex
)) >= 0);
3256 return (bool) (func
->ffs
->user_flags
&
3257 FUNCTIONFS_ALL_CTRL_RECIP
);
3261 static void ffs_func_suspend(struct usb_function
*f
)
3264 ffs_event_add(ffs_func_from_usb(f
)->ffs
, FUNCTIONFS_SUSPEND
);
3267 static void ffs_func_resume(struct usb_function
*f
)
3270 ffs_event_add(ffs_func_from_usb(f
)->ffs
, FUNCTIONFS_RESUME
);
3274 /* Endpoint and interface numbers reverse mapping ***************************/
3276 static int ffs_func_revmap_ep(struct ffs_function
*func
, u8 num
)
3278 num
= func
->eps_revmap
[num
& USB_ENDPOINT_NUMBER_MASK
];
3279 return num
? num
: -EDOM
;
3282 static int ffs_func_revmap_intf(struct ffs_function
*func
, u8 intf
)
3284 short *nums
= func
->interfaces_nums
;
3285 unsigned count
= func
->ffs
->interfaces_count
;
3287 for (; count
; --count
, ++nums
) {
3288 if (*nums
>= 0 && *nums
== intf
)
3289 return nums
- func
->interfaces_nums
;
3296 /* Devices management *******************************************************/
3298 static LIST_HEAD(ffs_devices
);
3300 static struct ffs_dev
*_ffs_do_find_dev(const char *name
)
3302 struct ffs_dev
*dev
;
3307 list_for_each_entry(dev
, &ffs_devices
, entry
) {
3308 if (strcmp(dev
->name
, name
) == 0)
3316 * ffs_lock must be taken by the caller of this function
3318 static struct ffs_dev
*_ffs_get_single_dev(void)
3320 struct ffs_dev
*dev
;
3322 if (list_is_singular(&ffs_devices
)) {
3323 dev
= list_first_entry(&ffs_devices
, struct ffs_dev
, entry
);
3332 * ffs_lock must be taken by the caller of this function
3334 static struct ffs_dev
*_ffs_find_dev(const char *name
)
3336 struct ffs_dev
*dev
;
3338 dev
= _ffs_get_single_dev();
3342 return _ffs_do_find_dev(name
);
3345 /* Configfs support *********************************************************/
3347 static inline struct f_fs_opts
*to_ffs_opts(struct config_item
*item
)
3349 return container_of(to_config_group(item
), struct f_fs_opts
,
3353 static void ffs_attr_release(struct config_item
*item
)
3355 struct f_fs_opts
*opts
= to_ffs_opts(item
);
3357 usb_put_function_instance(&opts
->func_inst
);
3360 static struct configfs_item_operations ffs_item_ops
= {
3361 .release
= ffs_attr_release
,
3364 static struct config_item_type ffs_func_type
= {
3365 .ct_item_ops
= &ffs_item_ops
,
3366 .ct_owner
= THIS_MODULE
,
3370 /* Function registration interface ******************************************/
3372 static void ffs_free_inst(struct usb_function_instance
*f
)
3374 struct f_fs_opts
*opts
;
3376 opts
= to_f_fs_opts(f
);
3378 _ffs_free_dev(opts
->dev
);
3383 static int ffs_set_inst_name(struct usb_function_instance
*fi
, const char *name
)
3385 if (strlen(name
) >= FIELD_SIZEOF(struct ffs_dev
, name
))
3386 return -ENAMETOOLONG
;
3387 return ffs_name_dev(to_f_fs_opts(fi
)->dev
, name
);
3390 static struct usb_function_instance
*ffs_alloc_inst(void)
3392 struct f_fs_opts
*opts
;
3393 struct ffs_dev
*dev
;
3395 opts
= kzalloc(sizeof(*opts
), GFP_KERNEL
);
3397 return ERR_PTR(-ENOMEM
);
3399 opts
->func_inst
.set_inst_name
= ffs_set_inst_name
;
3400 opts
->func_inst
.free_func_inst
= ffs_free_inst
;
3402 dev
= _ffs_alloc_dev();
3406 return ERR_CAST(dev
);
3411 config_group_init_type_name(&opts
->func_inst
.group
, "",
3413 return &opts
->func_inst
;
3416 static void ffs_free(struct usb_function
*f
)
3418 kfree(ffs_func_from_usb(f
));
3421 static void ffs_func_unbind(struct usb_configuration
*c
,
3422 struct usb_function
*f
)
3424 struct ffs_function
*func
= ffs_func_from_usb(f
);
3425 struct ffs_data
*ffs
= func
->ffs
;
3426 struct f_fs_opts
*opts
=
3427 container_of(f
->fi
, struct f_fs_opts
, func_inst
);
3428 struct ffs_ep
*ep
= func
->eps
;
3429 unsigned count
= ffs
->eps_count
;
3430 unsigned long flags
;
3433 if (ffs
->func
== func
) {
3434 ffs_func_eps_disable(func
);
3438 if (!--opts
->refcnt
)
3439 functionfs_unbind(ffs
);
3441 /* cleanup after autoconfig */
3442 spin_lock_irqsave(&func
->ffs
->eps_lock
, flags
);
3444 if (ep
->ep
&& ep
->req
)
3445 usb_ep_free_request(ep
->ep
, ep
->req
);
3449 spin_unlock_irqrestore(&func
->ffs
->eps_lock
, flags
);
3453 * eps, descriptors and interfaces_nums are allocated in the
3454 * same chunk so only one free is required.
3456 func
->function
.fs_descriptors
= NULL
;
3457 func
->function
.hs_descriptors
= NULL
;
3458 func
->function
.ss_descriptors
= NULL
;
3459 func
->interfaces_nums
= NULL
;
3461 ffs_event_add(ffs
, FUNCTIONFS_UNBIND
);
3464 static struct usb_function
*ffs_alloc(struct usb_function_instance
*fi
)
3466 struct ffs_function
*func
;
3470 func
= kzalloc(sizeof(*func
), GFP_KERNEL
);
3471 if (unlikely(!func
))
3472 return ERR_PTR(-ENOMEM
);
3474 func
->function
.name
= "Function FS Gadget";
3476 func
->function
.bind
= ffs_func_bind
;
3477 func
->function
.unbind
= ffs_func_unbind
;
3478 func
->function
.set_alt
= ffs_func_set_alt
;
3479 func
->function
.disable
= ffs_func_disable
;
3480 func
->function
.setup
= ffs_func_setup
;
3481 func
->function
.req_match
= ffs_func_req_match
;
3482 func
->function
.suspend
= ffs_func_suspend
;
3483 func
->function
.resume
= ffs_func_resume
;
3484 func
->function
.free_func
= ffs_free
;
3486 return &func
->function
;
3490 * ffs_lock must be taken by the caller of this function
3492 static struct ffs_dev
*_ffs_alloc_dev(void)
3494 struct ffs_dev
*dev
;
3497 if (_ffs_get_single_dev())
3498 return ERR_PTR(-EBUSY
);
3500 dev
= kzalloc(sizeof(*dev
), GFP_KERNEL
);
3502 return ERR_PTR(-ENOMEM
);
3504 if (list_empty(&ffs_devices
)) {
3505 ret
= functionfs_init();
3508 return ERR_PTR(ret
);
3512 list_add(&dev
->entry
, &ffs_devices
);
3517 int ffs_name_dev(struct ffs_dev
*dev
, const char *name
)
3519 struct ffs_dev
*existing
;
3524 existing
= _ffs_do_find_dev(name
);
3526 strlcpy(dev
->name
, name
, ARRAY_SIZE(dev
->name
));
3527 else if (existing
!= dev
)
3534 EXPORT_SYMBOL_GPL(ffs_name_dev
);
3536 int ffs_single_dev(struct ffs_dev
*dev
)
3543 if (!list_is_singular(&ffs_devices
))
3551 EXPORT_SYMBOL_GPL(ffs_single_dev
);
3554 * ffs_lock must be taken by the caller of this function
3556 static void _ffs_free_dev(struct ffs_dev
*dev
)
3558 list_del(&dev
->entry
);
3560 /* Clear the private_data pointer to stop incorrect dev access */
3562 dev
->ffs_data
->private_data
= NULL
;
3565 if (list_empty(&ffs_devices
))
3566 functionfs_cleanup();
3569 static void *ffs_acquire_dev(const char *dev_name
)
3571 struct ffs_dev
*ffs_dev
;
3576 ffs_dev
= _ffs_find_dev(dev_name
);
3578 ffs_dev
= ERR_PTR(-ENOENT
);
3579 else if (ffs_dev
->mounted
)
3580 ffs_dev
= ERR_PTR(-EBUSY
);
3581 else if (ffs_dev
->ffs_acquire_dev_callback
&&
3582 ffs_dev
->ffs_acquire_dev_callback(ffs_dev
))
3583 ffs_dev
= ERR_PTR(-ENOENT
);
3585 ffs_dev
->mounted
= true;
3591 static void ffs_release_dev(struct ffs_data
*ffs_data
)
3593 struct ffs_dev
*ffs_dev
;
3598 ffs_dev
= ffs_data
->private_data
;
3600 ffs_dev
->mounted
= false;
3602 if (ffs_dev
->ffs_release_dev_callback
)
3603 ffs_dev
->ffs_release_dev_callback(ffs_dev
);
3609 static int ffs_ready(struct ffs_data
*ffs
)
3611 struct ffs_dev
*ffs_obj
;
3617 ffs_obj
= ffs
->private_data
;
3622 if (WARN_ON(ffs_obj
->desc_ready
)) {
3627 ffs_obj
->desc_ready
= true;
3628 ffs_obj
->ffs_data
= ffs
;
3630 if (ffs_obj
->ffs_ready_callback
) {
3631 ret
= ffs_obj
->ffs_ready_callback(ffs
);
3636 set_bit(FFS_FL_CALL_CLOSED_CALLBACK
, &ffs
->flags
);
3642 static void ffs_closed(struct ffs_data
*ffs
)
3644 struct ffs_dev
*ffs_obj
;
3645 struct f_fs_opts
*opts
;
3646 struct config_item
*ci
;
3651 ffs_obj
= ffs
->private_data
;
3655 ffs_obj
->desc_ready
= false;
3657 if (test_and_clear_bit(FFS_FL_CALL_CLOSED_CALLBACK
, &ffs
->flags
) &&
3658 ffs_obj
->ffs_closed_callback
)
3659 ffs_obj
->ffs_closed_callback(ffs
);
3662 opts
= ffs_obj
->opts
;
3666 if (opts
->no_configfs
|| !opts
->func_inst
.group
.cg_item
.ci_parent
3667 || !kref_read(&opts
->func_inst
.group
.cg_item
.ci_kref
))
3670 ci
= opts
->func_inst
.group
.cg_item
.ci_parent
->ci_parent
;
3673 unregister_gadget_item(ci
);
3679 /* Misc helper functions ****************************************************/
3681 static int ffs_mutex_lock(struct mutex
*mutex
, unsigned nonblock
)
3684 ? likely(mutex_trylock(mutex
)) ? 0 : -EAGAIN
3685 : mutex_lock_interruptible(mutex
);
3688 static char *ffs_prepare_buffer(const char __user
*buf
, size_t len
)
3695 data
= kmalloc(len
, GFP_KERNEL
);
3696 if (unlikely(!data
))
3697 return ERR_PTR(-ENOMEM
);
3699 if (unlikely(copy_from_user(data
, buf
, len
))) {
3701 return ERR_PTR(-EFAULT
);
3704 pr_vdebug("Buffer from user space:\n");
3705 ffs_dump_mem("", data
, len
);
3710 DECLARE_USB_FUNCTION_INIT(ffs
, ffs_alloc_inst
, ffs_alloc
);
3711 MODULE_LICENSE("GPL");
3712 MODULE_AUTHOR("Michal Nazarewicz");