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(const char *dev_name
)
50 __attribute__((malloc
));
52 /* Opened counter handling. */
53 static void ffs_data_opened(struct ffs_data
*ffs
);
54 static void ffs_data_closed(struct ffs_data
*ffs
);
56 /* Called with ffs->mutex held; take over ownership of data. */
57 static int __must_check
58 __ffs_data_got_descs(struct ffs_data
*ffs
, char *data
, size_t len
);
59 static int __must_check
60 __ffs_data_got_strings(struct ffs_data
*ffs
, char *data
, size_t len
);
63 /* The function structure ***************************************************/
68 struct usb_configuration
*conf
;
69 struct usb_gadget
*gadget
;
74 short *interfaces_nums
;
76 struct usb_function function
;
80 static struct ffs_function
*ffs_func_from_usb(struct usb_function
*f
)
82 return container_of(f
, struct ffs_function
, function
);
86 static inline enum ffs_setup_state
87 ffs_setup_state_clear_cancelled(struct ffs_data
*ffs
)
89 return (enum ffs_setup_state
)
90 cmpxchg(&ffs
->setup_state
, FFS_SETUP_CANCELLED
, FFS_NO_SETUP
);
94 static void ffs_func_eps_disable(struct ffs_function
*func
);
95 static int __must_check
ffs_func_eps_enable(struct ffs_function
*func
);
97 static int ffs_func_bind(struct usb_configuration
*,
98 struct usb_function
*);
99 static int ffs_func_set_alt(struct usb_function
*, unsigned, unsigned);
100 static void ffs_func_disable(struct usb_function
*);
101 static int ffs_func_setup(struct usb_function
*,
102 const struct usb_ctrlrequest
*);
103 static bool ffs_func_req_match(struct usb_function
*,
104 const struct usb_ctrlrequest
*,
106 static void ffs_func_suspend(struct usb_function
*);
107 static void ffs_func_resume(struct usb_function
*);
110 static int ffs_func_revmap_ep(struct ffs_function
*func
, u8 num
);
111 static int ffs_func_revmap_intf(struct ffs_function
*func
, u8 intf
);
114 /* The endpoints structures *************************************************/
117 struct usb_ep
*ep
; /* P: ffs->eps_lock */
118 struct usb_request
*req
; /* P: epfile->mutex */
120 /* [0]: full speed, [1]: high speed, [2]: super speed */
121 struct usb_endpoint_descriptor
*descs
[3];
125 int status
; /* P: epfile->mutex */
129 /* Protects ep->ep and ep->req. */
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
;
784 struct ffs_data
*ffs
= io_data
->ffs
;
788 INIT_WORK(&io_data
->work
, ffs_user_copy_worker
);
789 queue_work(ffs
->io_completion_wq
, &io_data
->work
);
792 static void __ffs_epfile_read_buffer_free(struct ffs_epfile
*epfile
)
795 * See comment in struct ffs_epfile for full read_buffer pointer
796 * synchronisation story.
798 struct ffs_buffer
*buf
= xchg(&epfile
->read_buffer
, READ_BUFFER_DROP
);
799 if (buf
&& buf
!= READ_BUFFER_DROP
)
803 /* Assumes epfile->mutex is held. */
804 static ssize_t
__ffs_epfile_read_buffered(struct ffs_epfile
*epfile
,
805 struct iov_iter
*iter
)
808 * Null out epfile->read_buffer so ffs_func_eps_disable does not free
809 * the buffer while we are using it. See comment in struct ffs_epfile
810 * for full read_buffer pointer synchronisation story.
812 struct ffs_buffer
*buf
= xchg(&epfile
->read_buffer
, NULL
);
814 if (!buf
|| buf
== READ_BUFFER_DROP
)
817 ret
= copy_to_iter(buf
->data
, buf
->length
, iter
);
818 if (buf
->length
== ret
) {
823 if (unlikely(iov_iter_count(iter
))) {
830 if (cmpxchg(&epfile
->read_buffer
, NULL
, buf
))
836 /* Assumes epfile->mutex is held. */
837 static ssize_t
__ffs_epfile_read_data(struct ffs_epfile
*epfile
,
838 void *data
, int data_len
,
839 struct iov_iter
*iter
)
841 struct ffs_buffer
*buf
;
843 ssize_t ret
= copy_to_iter(data
, data_len
, iter
);
844 if (likely(data_len
== ret
))
847 if (unlikely(iov_iter_count(iter
)))
850 /* See ffs_copy_to_iter for more context. */
851 pr_warn("functionfs read size %d > requested size %zd, splitting request into multiple reads.",
855 buf
= kmalloc(sizeof(*buf
) + data_len
, GFP_KERNEL
);
858 buf
->length
= data_len
;
859 buf
->data
= buf
->storage
;
860 memcpy(buf
->storage
, data
+ ret
, data_len
);
863 * At this point read_buffer is NULL or READ_BUFFER_DROP (if
864 * ffs_func_eps_disable has been called in the meanwhile). See comment
865 * in struct ffs_epfile for full read_buffer pointer synchronisation
868 if (unlikely(cmpxchg(&epfile
->read_buffer
, NULL
, buf
)))
874 static ssize_t
ffs_epfile_io(struct file
*file
, struct ffs_io_data
*io_data
)
876 struct ffs_epfile
*epfile
= file
->private_data
;
877 struct usb_request
*req
;
880 ssize_t ret
, data_len
= -EINVAL
;
883 /* Are we still active? */
884 if (WARN_ON(epfile
->ffs
->state
!= FFS_ACTIVE
))
887 /* Wait for endpoint to be enabled */
890 if (file
->f_flags
& O_NONBLOCK
)
893 ret
= wait_event_interruptible(
894 epfile
->ffs
->wait
, (ep
= epfile
->ep
));
900 halt
= (!io_data
->read
== !epfile
->in
);
901 if (halt
&& epfile
->isoc
)
904 /* We will be using request and read_buffer */
905 ret
= ffs_mutex_lock(&epfile
->mutex
, file
->f_flags
& O_NONBLOCK
);
909 /* Allocate & copy */
911 struct usb_gadget
*gadget
;
914 * Do we have buffered data from previous partial read? Check
915 * that for synchronous case only because we do not have
916 * facility to ‘wake up’ a pending asynchronous read and push
917 * buffered data to it which we would need to make things behave
920 if (!io_data
->aio
&& io_data
->read
) {
921 ret
= __ffs_epfile_read_buffered(epfile
, &io_data
->data
);
927 * if we _do_ wait above, the epfile->ffs->gadget might be NULL
928 * before the waiting completes, so do not assign to 'gadget'
931 gadget
= epfile
->ffs
->gadget
;
933 spin_lock_irq(&epfile
->ffs
->eps_lock
);
934 /* In the meantime, endpoint got disabled or changed. */
935 if (epfile
->ep
!= ep
) {
939 data_len
= iov_iter_count(&io_data
->data
);
941 * Controller may require buffer size to be aligned to
942 * maxpacketsize of an out endpoint.
945 data_len
= usb_ep_align_maybe(gadget
, ep
->ep
, data_len
);
946 spin_unlock_irq(&epfile
->ffs
->eps_lock
);
948 data
= kmalloc(data_len
, GFP_KERNEL
);
949 if (unlikely(!data
)) {
953 if (!io_data
->read
&&
954 !copy_from_iter_full(data
, data_len
, &io_data
->data
)) {
960 spin_lock_irq(&epfile
->ffs
->eps_lock
);
962 if (epfile
->ep
!= ep
) {
963 /* In the meantime, endpoint got disabled or changed. */
966 ret
= usb_ep_set_halt(ep
->ep
);
969 } else if (unlikely(data_len
== -EINVAL
)) {
971 * Sanity Check: even though data_len can't be used
972 * uninitialized at the time I write this comment, some
973 * compilers complain about this situation.
974 * In order to keep the code clean from warnings, data_len is
975 * being initialized to -EINVAL during its declaration, which
976 * means we can't rely on compiler anymore to warn no future
977 * changes won't result in data_len being used uninitialized.
978 * For such reason, we're adding this redundant sanity check
981 WARN(1, "%s: data_len == -EINVAL\n", __func__
);
983 } else if (!io_data
->aio
) {
984 DECLARE_COMPLETION_ONSTACK(done
);
985 bool interrupted
= false;
989 req
->length
= data_len
;
991 req
->context
= &done
;
992 req
->complete
= ffs_epfile_io_complete
;
994 ret
= usb_ep_queue(ep
->ep
, req
, GFP_ATOMIC
);
995 if (unlikely(ret
< 0))
998 spin_unlock_irq(&epfile
->ffs
->eps_lock
);
1000 if (unlikely(wait_for_completion_interruptible(&done
))) {
1002 * To avoid race condition with ffs_epfile_io_complete,
1003 * dequeue the request first then check
1004 * status. usb_ep_dequeue API should guarantee no race
1005 * condition with req->complete callback.
1007 usb_ep_dequeue(ep
->ep
, req
);
1008 interrupted
= ep
->status
< 0;
1013 else if (io_data
->read
&& ep
->status
> 0)
1014 ret
= __ffs_epfile_read_data(epfile
, data
, ep
->status
,
1019 } else if (!(req
= usb_ep_alloc_request(ep
->ep
, GFP_KERNEL
))) {
1023 req
->length
= data_len
;
1025 io_data
->buf
= data
;
1026 io_data
->ep
= ep
->ep
;
1028 io_data
->ffs
= epfile
->ffs
;
1030 req
->context
= io_data
;
1031 req
->complete
= ffs_epfile_async_io_complete
;
1033 ret
= usb_ep_queue(ep
->ep
, req
, GFP_ATOMIC
);
1034 if (unlikely(ret
)) {
1035 usb_ep_free_request(ep
->ep
, req
);
1041 * Do not kfree the buffer in this function. It will be freed
1042 * by ffs_user_copy_worker.
1048 spin_unlock_irq(&epfile
->ffs
->eps_lock
);
1050 mutex_unlock(&epfile
->mutex
);
1057 ffs_epfile_open(struct inode
*inode
, struct file
*file
)
1059 struct ffs_epfile
*epfile
= inode
->i_private
;
1063 if (WARN_ON(epfile
->ffs
->state
!= FFS_ACTIVE
))
1066 file
->private_data
= epfile
;
1067 ffs_data_opened(epfile
->ffs
);
1072 static int ffs_aio_cancel(struct kiocb
*kiocb
)
1074 struct ffs_io_data
*io_data
= kiocb
->private;
1075 struct ffs_epfile
*epfile
= kiocb
->ki_filp
->private_data
;
1080 spin_lock_irq(&epfile
->ffs
->eps_lock
);
1082 if (likely(io_data
&& io_data
->ep
&& io_data
->req
))
1083 value
= usb_ep_dequeue(io_data
->ep
, io_data
->req
);
1087 spin_unlock_irq(&epfile
->ffs
->eps_lock
);
1092 static ssize_t
ffs_epfile_write_iter(struct kiocb
*kiocb
, struct iov_iter
*from
)
1094 struct ffs_io_data io_data
, *p
= &io_data
;
1099 if (!is_sync_kiocb(kiocb
)) {
1100 p
= kmalloc(sizeof(io_data
), GFP_KERNEL
);
1111 p
->mm
= current
->mm
;
1116 kiocb_set_cancel_fn(kiocb
, ffs_aio_cancel
);
1118 res
= ffs_epfile_io(kiocb
->ki_filp
, p
);
1119 if (res
== -EIOCBQUEUED
)
1128 static ssize_t
ffs_epfile_read_iter(struct kiocb
*kiocb
, struct iov_iter
*to
)
1130 struct ffs_io_data io_data
, *p
= &io_data
;
1135 if (!is_sync_kiocb(kiocb
)) {
1136 p
= kmalloc(sizeof(io_data
), GFP_KERNEL
);
1147 p
->to_free
= dup_iter(&p
->data
, to
, GFP_KERNEL
);
1156 p
->mm
= current
->mm
;
1161 kiocb_set_cancel_fn(kiocb
, ffs_aio_cancel
);
1163 res
= ffs_epfile_io(kiocb
->ki_filp
, p
);
1164 if (res
== -EIOCBQUEUED
)
1177 ffs_epfile_release(struct inode
*inode
, struct file
*file
)
1179 struct ffs_epfile
*epfile
= inode
->i_private
;
1183 __ffs_epfile_read_buffer_free(epfile
);
1184 ffs_data_closed(epfile
->ffs
);
1189 static long ffs_epfile_ioctl(struct file
*file
, unsigned code
,
1190 unsigned long value
)
1192 struct ffs_epfile
*epfile
= file
->private_data
;
1198 if (WARN_ON(epfile
->ffs
->state
!= FFS_ACTIVE
))
1201 /* Wait for endpoint to be enabled */
1204 if (file
->f_flags
& O_NONBLOCK
)
1207 ret
= wait_event_interruptible(
1208 epfile
->ffs
->wait
, (ep
= epfile
->ep
));
1213 spin_lock_irq(&epfile
->ffs
->eps_lock
);
1215 /* In the meantime, endpoint got disabled or changed. */
1216 if (epfile
->ep
!= ep
) {
1217 spin_unlock_irq(&epfile
->ffs
->eps_lock
);
1222 case FUNCTIONFS_FIFO_STATUS
:
1223 ret
= usb_ep_fifo_status(epfile
->ep
->ep
);
1225 case FUNCTIONFS_FIFO_FLUSH
:
1226 usb_ep_fifo_flush(epfile
->ep
->ep
);
1229 case FUNCTIONFS_CLEAR_HALT
:
1230 ret
= usb_ep_clear_halt(epfile
->ep
->ep
);
1232 case FUNCTIONFS_ENDPOINT_REVMAP
:
1233 ret
= epfile
->ep
->num
;
1235 case FUNCTIONFS_ENDPOINT_DESC
:
1238 struct usb_endpoint_descriptor
*desc
;
1240 switch (epfile
->ffs
->gadget
->speed
) {
1241 case USB_SPEED_SUPER
:
1244 case USB_SPEED_HIGH
:
1250 desc
= epfile
->ep
->descs
[desc_idx
];
1252 spin_unlock_irq(&epfile
->ffs
->eps_lock
);
1253 ret
= copy_to_user((void *)value
, desc
, desc
->bLength
);
1261 spin_unlock_irq(&epfile
->ffs
->eps_lock
);
1266 static const struct file_operations ffs_epfile_operations
= {
1267 .llseek
= no_llseek
,
1269 .open
= ffs_epfile_open
,
1270 .write_iter
= ffs_epfile_write_iter
,
1271 .read_iter
= ffs_epfile_read_iter
,
1272 .release
= ffs_epfile_release
,
1273 .unlocked_ioctl
= ffs_epfile_ioctl
,
1277 /* File system and super block operations ***********************************/
1280 * Mounting the file system creates a controller file, used first for
1281 * function configuration then later for event monitoring.
1284 static struct inode
*__must_check
1285 ffs_sb_make_inode(struct super_block
*sb
, void *data
,
1286 const struct file_operations
*fops
,
1287 const struct inode_operations
*iops
,
1288 struct ffs_file_perms
*perms
)
1290 struct inode
*inode
;
1294 inode
= new_inode(sb
);
1296 if (likely(inode
)) {
1297 struct timespec ts
= current_time(inode
);
1299 inode
->i_ino
= get_next_ino();
1300 inode
->i_mode
= perms
->mode
;
1301 inode
->i_uid
= perms
->uid
;
1302 inode
->i_gid
= perms
->gid
;
1303 inode
->i_atime
= ts
;
1304 inode
->i_mtime
= ts
;
1305 inode
->i_ctime
= ts
;
1306 inode
->i_private
= data
;
1308 inode
->i_fop
= fops
;
1316 /* Create "regular" file */
1317 static struct dentry
*ffs_sb_create_file(struct super_block
*sb
,
1318 const char *name
, void *data
,
1319 const struct file_operations
*fops
)
1321 struct ffs_data
*ffs
= sb
->s_fs_info
;
1322 struct dentry
*dentry
;
1323 struct inode
*inode
;
1327 dentry
= d_alloc_name(sb
->s_root
, name
);
1328 if (unlikely(!dentry
))
1331 inode
= ffs_sb_make_inode(sb
, data
, fops
, NULL
, &ffs
->file_perms
);
1332 if (unlikely(!inode
)) {
1337 d_add(dentry
, inode
);
1342 static const struct super_operations ffs_sb_operations
= {
1343 .statfs
= simple_statfs
,
1344 .drop_inode
= generic_delete_inode
,
1347 struct ffs_sb_fill_data
{
1348 struct ffs_file_perms perms
;
1350 const char *dev_name
;
1352 struct ffs_data
*ffs_data
;
1355 static int ffs_sb_fill(struct super_block
*sb
, void *_data
, int silent
)
1357 struct ffs_sb_fill_data
*data
= _data
;
1358 struct inode
*inode
;
1359 struct ffs_data
*ffs
= data
->ffs_data
;
1364 data
->ffs_data
= NULL
;
1365 sb
->s_fs_info
= ffs
;
1366 sb
->s_blocksize
= PAGE_SIZE
;
1367 sb
->s_blocksize_bits
= PAGE_SHIFT
;
1368 sb
->s_magic
= FUNCTIONFS_MAGIC
;
1369 sb
->s_op
= &ffs_sb_operations
;
1370 sb
->s_time_gran
= 1;
1373 data
->perms
.mode
= data
->root_mode
;
1374 inode
= ffs_sb_make_inode(sb
, NULL
,
1375 &simple_dir_operations
,
1376 &simple_dir_inode_operations
,
1378 sb
->s_root
= d_make_root(inode
);
1379 if (unlikely(!sb
->s_root
))
1383 if (unlikely(!ffs_sb_create_file(sb
, "ep0", ffs
,
1384 &ffs_ep0_operations
)))
1390 static int ffs_fs_parse_opts(struct ffs_sb_fill_data
*data
, char *opts
)
1394 if (!opts
|| !*opts
)
1398 unsigned long value
;
1402 comma
= strchr(opts
, ',');
1407 eq
= strchr(opts
, '=');
1408 if (unlikely(!eq
)) {
1409 pr_err("'=' missing in %s\n", opts
);
1415 if (kstrtoul(eq
+ 1, 0, &value
)) {
1416 pr_err("%s: invalid value: %s\n", opts
, eq
+ 1);
1420 /* Interpret option */
1421 switch (eq
- opts
) {
1423 if (!memcmp(opts
, "no_disconnect", 13))
1424 data
->no_disconnect
= !!value
;
1429 if (!memcmp(opts
, "rmode", 5))
1430 data
->root_mode
= (value
& 0555) | S_IFDIR
;
1431 else if (!memcmp(opts
, "fmode", 5))
1432 data
->perms
.mode
= (value
& 0666) | S_IFREG
;
1438 if (!memcmp(opts
, "mode", 4)) {
1439 data
->root_mode
= (value
& 0555) | S_IFDIR
;
1440 data
->perms
.mode
= (value
& 0666) | S_IFREG
;
1447 if (!memcmp(opts
, "uid", 3)) {
1448 data
->perms
.uid
= make_kuid(current_user_ns(), value
);
1449 if (!uid_valid(data
->perms
.uid
)) {
1450 pr_err("%s: unmapped value: %lu\n", opts
, value
);
1453 } else if (!memcmp(opts
, "gid", 3)) {
1454 data
->perms
.gid
= make_kgid(current_user_ns(), value
);
1455 if (!gid_valid(data
->perms
.gid
)) {
1456 pr_err("%s: unmapped value: %lu\n", opts
, value
);
1466 pr_err("%s: invalid option\n", opts
);
1470 /* Next iteration */
1479 /* "mount -t functionfs dev_name /dev/function" ends up here */
1481 static struct dentry
*
1482 ffs_fs_mount(struct file_system_type
*t
, int flags
,
1483 const char *dev_name
, void *opts
)
1485 struct ffs_sb_fill_data data
= {
1487 .mode
= S_IFREG
| 0600,
1488 .uid
= GLOBAL_ROOT_UID
,
1489 .gid
= GLOBAL_ROOT_GID
,
1491 .root_mode
= S_IFDIR
| 0500,
1492 .no_disconnect
= false,
1497 struct ffs_data
*ffs
;
1501 ret
= ffs_fs_parse_opts(&data
, opts
);
1502 if (unlikely(ret
< 0))
1503 return ERR_PTR(ret
);
1505 ffs
= ffs_data_new(dev_name
);
1507 return ERR_PTR(-ENOMEM
);
1508 ffs
->file_perms
= data
.perms
;
1509 ffs
->no_disconnect
= data
.no_disconnect
;
1511 ffs
->dev_name
= kstrdup(dev_name
, GFP_KERNEL
);
1512 if (unlikely(!ffs
->dev_name
)) {
1514 return ERR_PTR(-ENOMEM
);
1517 ffs_dev
= ffs_acquire_dev(dev_name
);
1518 if (IS_ERR(ffs_dev
)) {
1520 return ERR_CAST(ffs_dev
);
1522 ffs
->private_data
= ffs_dev
;
1523 data
.ffs_data
= ffs
;
1525 rv
= mount_nodev(t
, flags
, &data
, ffs_sb_fill
);
1526 if (IS_ERR(rv
) && data
.ffs_data
) {
1527 ffs_release_dev(data
.ffs_data
);
1528 ffs_data_put(data
.ffs_data
);
1534 ffs_fs_kill_sb(struct super_block
*sb
)
1538 kill_litter_super(sb
);
1539 if (sb
->s_fs_info
) {
1540 ffs_release_dev(sb
->s_fs_info
);
1541 ffs_data_closed(sb
->s_fs_info
);
1542 ffs_data_put(sb
->s_fs_info
);
1546 static struct file_system_type ffs_fs_type
= {
1547 .owner
= THIS_MODULE
,
1548 .name
= "functionfs",
1549 .mount
= ffs_fs_mount
,
1550 .kill_sb
= ffs_fs_kill_sb
,
1552 MODULE_ALIAS_FS("functionfs");
1555 /* Driver's main init/cleanup functions *************************************/
1557 static int functionfs_init(void)
1563 ret
= register_filesystem(&ffs_fs_type
);
1565 pr_info("file system registered\n");
1567 pr_err("failed registering file system (%d)\n", ret
);
1572 static void functionfs_cleanup(void)
1576 pr_info("unloading\n");
1577 unregister_filesystem(&ffs_fs_type
);
1581 /* ffs_data and ffs_function construction and destruction code **************/
1583 static void ffs_data_clear(struct ffs_data
*ffs
);
1584 static void ffs_data_reset(struct ffs_data
*ffs
);
1586 static void ffs_data_get(struct ffs_data
*ffs
)
1590 refcount_inc(&ffs
->ref
);
1593 static void ffs_data_opened(struct ffs_data
*ffs
)
1597 refcount_inc(&ffs
->ref
);
1598 if (atomic_add_return(1, &ffs
->opened
) == 1 &&
1599 ffs
->state
== FFS_DEACTIVATED
) {
1600 ffs
->state
= FFS_CLOSING
;
1601 ffs_data_reset(ffs
);
1605 static void ffs_data_put(struct ffs_data
*ffs
)
1609 if (unlikely(refcount_dec_and_test(&ffs
->ref
))) {
1610 pr_info("%s(): freeing\n", __func__
);
1611 ffs_data_clear(ffs
);
1612 BUG_ON(waitqueue_active(&ffs
->ev
.waitq
) ||
1613 waitqueue_active(&ffs
->ep0req_completion
.wait
) ||
1614 waitqueue_active(&ffs
->wait
));
1615 destroy_workqueue(ffs
->io_completion_wq
);
1616 kfree(ffs
->dev_name
);
1621 static void ffs_data_closed(struct ffs_data
*ffs
)
1625 if (atomic_dec_and_test(&ffs
->opened
)) {
1626 if (ffs
->no_disconnect
) {
1627 ffs
->state
= FFS_DEACTIVATED
;
1629 ffs_epfiles_destroy(ffs
->epfiles
,
1631 ffs
->epfiles
= NULL
;
1633 if (ffs
->setup_state
== FFS_SETUP_PENDING
)
1634 __ffs_ep0_stall(ffs
);
1636 ffs
->state
= FFS_CLOSING
;
1637 ffs_data_reset(ffs
);
1640 if (atomic_read(&ffs
->opened
) < 0) {
1641 ffs
->state
= FFS_CLOSING
;
1642 ffs_data_reset(ffs
);
1648 static struct ffs_data
*ffs_data_new(const char *dev_name
)
1650 struct ffs_data
*ffs
= kzalloc(sizeof *ffs
, GFP_KERNEL
);
1656 ffs
->io_completion_wq
= alloc_ordered_workqueue("%s", 0, dev_name
);
1657 if (!ffs
->io_completion_wq
) {
1662 refcount_set(&ffs
->ref
, 1);
1663 atomic_set(&ffs
->opened
, 0);
1664 ffs
->state
= FFS_READ_DESCRIPTORS
;
1665 mutex_init(&ffs
->mutex
);
1666 spin_lock_init(&ffs
->eps_lock
);
1667 init_waitqueue_head(&ffs
->ev
.waitq
);
1668 init_waitqueue_head(&ffs
->wait
);
1669 init_completion(&ffs
->ep0req_completion
);
1671 /* XXX REVISIT need to update it in some places, or do we? */
1672 ffs
->ev
.can_stall
= 1;
1677 static void ffs_data_clear(struct ffs_data
*ffs
)
1683 BUG_ON(ffs
->gadget
);
1686 ffs_epfiles_destroy(ffs
->epfiles
, ffs
->eps_count
);
1688 if (ffs
->ffs_eventfd
)
1689 eventfd_ctx_put(ffs
->ffs_eventfd
);
1691 kfree(ffs
->raw_descs_data
);
1692 kfree(ffs
->raw_strings
);
1693 kfree(ffs
->stringtabs
);
1696 static void ffs_data_reset(struct ffs_data
*ffs
)
1700 ffs_data_clear(ffs
);
1702 ffs
->epfiles
= NULL
;
1703 ffs
->raw_descs_data
= NULL
;
1704 ffs
->raw_descs
= NULL
;
1705 ffs
->raw_strings
= NULL
;
1706 ffs
->stringtabs
= NULL
;
1708 ffs
->raw_descs_length
= 0;
1709 ffs
->fs_descs_count
= 0;
1710 ffs
->hs_descs_count
= 0;
1711 ffs
->ss_descs_count
= 0;
1713 ffs
->strings_count
= 0;
1714 ffs
->interfaces_count
= 0;
1719 ffs
->state
= FFS_READ_DESCRIPTORS
;
1720 ffs
->setup_state
= FFS_NO_SETUP
;
1725 static int functionfs_bind(struct ffs_data
*ffs
, struct usb_composite_dev
*cdev
)
1727 struct usb_gadget_strings
**lang
;
1732 if (WARN_ON(ffs
->state
!= FFS_ACTIVE
1733 || test_and_set_bit(FFS_FL_BOUND
, &ffs
->flags
)))
1736 first_id
= usb_string_ids_n(cdev
, ffs
->strings_count
);
1737 if (unlikely(first_id
< 0))
1740 ffs
->ep0req
= usb_ep_alloc_request(cdev
->gadget
->ep0
, GFP_KERNEL
);
1741 if (unlikely(!ffs
->ep0req
))
1743 ffs
->ep0req
->complete
= ffs_ep0_complete
;
1744 ffs
->ep0req
->context
= ffs
;
1746 lang
= ffs
->stringtabs
;
1748 for (; *lang
; ++lang
) {
1749 struct usb_string
*str
= (*lang
)->strings
;
1751 for (; str
->s
; ++id
, ++str
)
1756 ffs
->gadget
= cdev
->gadget
;
1761 static void functionfs_unbind(struct ffs_data
*ffs
)
1765 if (!WARN_ON(!ffs
->gadget
)) {
1766 usb_ep_free_request(ffs
->gadget
->ep0
, ffs
->ep0req
);
1769 clear_bit(FFS_FL_BOUND
, &ffs
->flags
);
1774 static int ffs_epfiles_create(struct ffs_data
*ffs
)
1776 struct ffs_epfile
*epfile
, *epfiles
;
1781 count
= ffs
->eps_count
;
1782 epfiles
= kcalloc(count
, sizeof(*epfiles
), GFP_KERNEL
);
1787 for (i
= 1; i
<= count
; ++i
, ++epfile
) {
1789 mutex_init(&epfile
->mutex
);
1790 if (ffs
->user_flags
& FUNCTIONFS_VIRTUAL_ADDR
)
1791 sprintf(epfile
->name
, "ep%02x", ffs
->eps_addrmap
[i
]);
1793 sprintf(epfile
->name
, "ep%u", i
);
1794 epfile
->dentry
= ffs_sb_create_file(ffs
->sb
, epfile
->name
,
1796 &ffs_epfile_operations
);
1797 if (unlikely(!epfile
->dentry
)) {
1798 ffs_epfiles_destroy(epfiles
, i
- 1);
1803 ffs
->epfiles
= epfiles
;
1807 static void ffs_epfiles_destroy(struct ffs_epfile
*epfiles
, unsigned count
)
1809 struct ffs_epfile
*epfile
= epfiles
;
1813 for (; count
; --count
, ++epfile
) {
1814 BUG_ON(mutex_is_locked(&epfile
->mutex
));
1815 if (epfile
->dentry
) {
1816 d_delete(epfile
->dentry
);
1817 dput(epfile
->dentry
);
1818 epfile
->dentry
= NULL
;
1825 static void ffs_func_eps_disable(struct ffs_function
*func
)
1827 struct ffs_ep
*ep
= func
->eps
;
1828 struct ffs_epfile
*epfile
= func
->ffs
->epfiles
;
1829 unsigned count
= func
->ffs
->eps_count
;
1830 unsigned long flags
;
1832 spin_lock_irqsave(&func
->ffs
->eps_lock
, flags
);
1834 /* pending requests get nuked */
1836 usb_ep_disable(ep
->ep
);
1841 __ffs_epfile_read_buffer_free(epfile
);
1845 spin_unlock_irqrestore(&func
->ffs
->eps_lock
, flags
);
1848 static int ffs_func_eps_enable(struct ffs_function
*func
)
1850 struct ffs_data
*ffs
= func
->ffs
;
1851 struct ffs_ep
*ep
= func
->eps
;
1852 struct ffs_epfile
*epfile
= ffs
->epfiles
;
1853 unsigned count
= ffs
->eps_count
;
1854 unsigned long flags
;
1857 spin_lock_irqsave(&func
->ffs
->eps_lock
, flags
);
1859 struct usb_endpoint_descriptor
*ds
;
1860 struct usb_ss_ep_comp_descriptor
*comp_desc
= NULL
;
1861 int needs_comp_desc
= false;
1864 if (ffs
->gadget
->speed
== USB_SPEED_SUPER
) {
1866 needs_comp_desc
= true;
1867 } else if (ffs
->gadget
->speed
== USB_SPEED_HIGH
)
1872 /* fall-back to lower speed if desc missing for current speed */
1874 ds
= ep
->descs
[desc_idx
];
1875 } while (!ds
&& --desc_idx
>= 0);
1882 ep
->ep
->driver_data
= ep
;
1885 if (needs_comp_desc
) {
1886 comp_desc
= (struct usb_ss_ep_comp_descriptor
*)(ds
+
1887 USB_DT_ENDPOINT_SIZE
);
1888 ep
->ep
->maxburst
= comp_desc
->bMaxBurst
+ 1;
1889 ep
->ep
->comp_desc
= comp_desc
;
1892 ret
= usb_ep_enable(ep
->ep
);
1895 epfile
->in
= usb_endpoint_dir_in(ds
);
1896 epfile
->isoc
= usb_endpoint_xfer_isoc(ds
);
1905 wake_up_interruptible(&ffs
->wait
);
1906 spin_unlock_irqrestore(&func
->ffs
->eps_lock
, flags
);
1912 /* Parsing and building descriptors and strings *****************************/
1915 * This validates if data pointed by data is a valid USB descriptor as
1916 * well as record how many interfaces, endpoints and strings are
1917 * required by given configuration. Returns address after the
1918 * descriptor or NULL if data is invalid.
1921 enum ffs_entity_type
{
1922 FFS_DESCRIPTOR
, FFS_INTERFACE
, FFS_STRING
, FFS_ENDPOINT
1925 enum ffs_os_desc_type
{
1926 FFS_OS_DESC
, FFS_OS_DESC_EXT_COMPAT
, FFS_OS_DESC_EXT_PROP
1929 typedef int (*ffs_entity_callback
)(enum ffs_entity_type entity
,
1931 struct usb_descriptor_header
*desc
,
1934 typedef int (*ffs_os_desc_callback
)(enum ffs_os_desc_type entity
,
1935 struct usb_os_desc_header
*h
, void *data
,
1936 unsigned len
, void *priv
);
1938 static int __must_check
ffs_do_single_desc(char *data
, unsigned len
,
1939 ffs_entity_callback entity
,
1942 struct usb_descriptor_header
*_ds
= (void *)data
;
1948 /* At least two bytes are required: length and type */
1950 pr_vdebug("descriptor too short\n");
1954 /* If we have at least as many bytes as the descriptor takes? */
1955 length
= _ds
->bLength
;
1957 pr_vdebug("descriptor longer then available data\n");
1961 #define __entity_check_INTERFACE(val) 1
1962 #define __entity_check_STRING(val) (val)
1963 #define __entity_check_ENDPOINT(val) ((val) & USB_ENDPOINT_NUMBER_MASK)
1964 #define __entity(type, val) do { \
1965 pr_vdebug("entity " #type "(%02x)\n", (val)); \
1966 if (unlikely(!__entity_check_ ##type(val))) { \
1967 pr_vdebug("invalid entity's value\n"); \
1970 ret = entity(FFS_ ##type, &val, _ds, priv); \
1971 if (unlikely(ret < 0)) { \
1972 pr_debug("entity " #type "(%02x); ret = %d\n", \
1978 /* Parse descriptor depending on type. */
1979 switch (_ds
->bDescriptorType
) {
1983 case USB_DT_DEVICE_QUALIFIER
:
1984 /* function can't have any of those */
1985 pr_vdebug("descriptor reserved for gadget: %d\n",
1986 _ds
->bDescriptorType
);
1989 case USB_DT_INTERFACE
: {
1990 struct usb_interface_descriptor
*ds
= (void *)_ds
;
1991 pr_vdebug("interface descriptor\n");
1992 if (length
!= sizeof *ds
)
1995 __entity(INTERFACE
, ds
->bInterfaceNumber
);
1997 __entity(STRING
, ds
->iInterface
);
2001 case USB_DT_ENDPOINT
: {
2002 struct usb_endpoint_descriptor
*ds
= (void *)_ds
;
2003 pr_vdebug("endpoint descriptor\n");
2004 if (length
!= USB_DT_ENDPOINT_SIZE
&&
2005 length
!= USB_DT_ENDPOINT_AUDIO_SIZE
)
2007 __entity(ENDPOINT
, ds
->bEndpointAddress
);
2012 pr_vdebug("hid descriptor\n");
2013 if (length
!= sizeof(struct hid_descriptor
))
2018 if (length
!= sizeof(struct usb_otg_descriptor
))
2022 case USB_DT_INTERFACE_ASSOCIATION
: {
2023 struct usb_interface_assoc_descriptor
*ds
= (void *)_ds
;
2024 pr_vdebug("interface association descriptor\n");
2025 if (length
!= sizeof *ds
)
2028 __entity(STRING
, ds
->iFunction
);
2032 case USB_DT_SS_ENDPOINT_COMP
:
2033 pr_vdebug("EP SS companion descriptor\n");
2034 if (length
!= sizeof(struct usb_ss_ep_comp_descriptor
))
2038 case USB_DT_OTHER_SPEED_CONFIG
:
2039 case USB_DT_INTERFACE_POWER
:
2041 case USB_DT_SECURITY
:
2042 case USB_DT_CS_RADIO_CONTROL
:
2044 pr_vdebug("unimplemented descriptor: %d\n", _ds
->bDescriptorType
);
2048 /* We should never be here */
2049 pr_vdebug("unknown descriptor: %d\n", _ds
->bDescriptorType
);
2053 pr_vdebug("invalid length: %d (descriptor %d)\n",
2054 _ds
->bLength
, _ds
->bDescriptorType
);
2059 #undef __entity_check_DESCRIPTOR
2060 #undef __entity_check_INTERFACE
2061 #undef __entity_check_STRING
2062 #undef __entity_check_ENDPOINT
2067 static int __must_check
ffs_do_descs(unsigned count
, char *data
, unsigned len
,
2068 ffs_entity_callback entity
, void *priv
)
2070 const unsigned _len
= len
;
2071 unsigned long num
= 0;
2081 /* Record "descriptor" entity */
2082 ret
= entity(FFS_DESCRIPTOR
, (u8
*)num
, (void *)data
, priv
);
2083 if (unlikely(ret
< 0)) {
2084 pr_debug("entity DESCRIPTOR(%02lx); ret = %d\n",
2092 ret
= ffs_do_single_desc(data
, len
, entity
, priv
);
2093 if (unlikely(ret
< 0)) {
2094 pr_debug("%s returns %d\n", __func__
, ret
);
2104 static int __ffs_data_do_entity(enum ffs_entity_type type
,
2105 u8
*valuep
, struct usb_descriptor_header
*desc
,
2108 struct ffs_desc_helper
*helper
= priv
;
2109 struct usb_endpoint_descriptor
*d
;
2114 case FFS_DESCRIPTOR
:
2119 * Interfaces are indexed from zero so if we
2120 * encountered interface "n" then there are at least
2123 if (*valuep
>= helper
->interfaces_count
)
2124 helper
->interfaces_count
= *valuep
+ 1;
2129 * Strings are indexed from 1 (0 is reserved
2130 * for languages list)
2132 if (*valuep
> helper
->ffs
->strings_count
)
2133 helper
->ffs
->strings_count
= *valuep
;
2138 helper
->eps_count
++;
2139 if (helper
->eps_count
>= FFS_MAX_EPS_COUNT
)
2141 /* Check if descriptors for any speed were already parsed */
2142 if (!helper
->ffs
->eps_count
&& !helper
->ffs
->interfaces_count
)
2143 helper
->ffs
->eps_addrmap
[helper
->eps_count
] =
2144 d
->bEndpointAddress
;
2145 else if (helper
->ffs
->eps_addrmap
[helper
->eps_count
] !=
2146 d
->bEndpointAddress
)
2154 static int __ffs_do_os_desc_header(enum ffs_os_desc_type
*next_type
,
2155 struct usb_os_desc_header
*desc
)
2157 u16 bcd_version
= le16_to_cpu(desc
->bcdVersion
);
2158 u16 w_index
= le16_to_cpu(desc
->wIndex
);
2160 if (bcd_version
!= 1) {
2161 pr_vdebug("unsupported os descriptors version: %d",
2167 *next_type
= FFS_OS_DESC_EXT_COMPAT
;
2170 *next_type
= FFS_OS_DESC_EXT_PROP
;
2173 pr_vdebug("unsupported os descriptor type: %d", w_index
);
2177 return sizeof(*desc
);
2181 * Process all extended compatibility/extended property descriptors
2182 * of a feature descriptor
2184 static int __must_check
ffs_do_single_os_desc(char *data
, unsigned len
,
2185 enum ffs_os_desc_type type
,
2187 ffs_os_desc_callback entity
,
2189 struct usb_os_desc_header
*h
)
2192 const unsigned _len
= len
;
2196 /* loop over all ext compat/ext prop descriptors */
2197 while (feature_count
--) {
2198 ret
= entity(type
, h
, data
, len
, priv
);
2199 if (unlikely(ret
< 0)) {
2200 pr_debug("bad OS descriptor, type: %d\n", type
);
2209 /* Process a number of complete Feature Descriptors (Ext Compat or Ext Prop) */
2210 static int __must_check
ffs_do_os_descs(unsigned count
,
2211 char *data
, unsigned len
,
2212 ffs_os_desc_callback entity
, void *priv
)
2214 const unsigned _len
= len
;
2215 unsigned long num
= 0;
2219 for (num
= 0; num
< count
; ++num
) {
2221 enum ffs_os_desc_type type
;
2223 struct usb_os_desc_header
*desc
= (void *)data
;
2225 if (len
< sizeof(*desc
))
2229 * Record "descriptor" entity.
2230 * Process dwLength, bcdVersion, wIndex, get b/wCount.
2231 * Move the data pointer to the beginning of extended
2232 * compatibilities proper or extended properties proper
2233 * portions of the data
2235 if (le32_to_cpu(desc
->dwLength
) > len
)
2238 ret
= __ffs_do_os_desc_header(&type
, desc
);
2239 if (unlikely(ret
< 0)) {
2240 pr_debug("entity OS_DESCRIPTOR(%02lx); ret = %d\n",
2245 * 16-bit hex "?? 00" Little Endian looks like 8-bit hex "??"
2247 feature_count
= le16_to_cpu(desc
->wCount
);
2248 if (type
== FFS_OS_DESC_EXT_COMPAT
&&
2249 (feature_count
> 255 || desc
->Reserved
))
2255 * Process all function/property descriptors
2256 * of this Feature Descriptor
2258 ret
= ffs_do_single_os_desc(data
, len
, type
,
2259 feature_count
, entity
, priv
, desc
);
2260 if (unlikely(ret
< 0)) {
2261 pr_debug("%s returns %d\n", __func__
, ret
);
2272 * Validate contents of the buffer from userspace related to OS descriptors.
2274 static int __ffs_data_do_os_desc(enum ffs_os_desc_type type
,
2275 struct usb_os_desc_header
*h
, void *data
,
2276 unsigned len
, void *priv
)
2278 struct ffs_data
*ffs
= priv
;
2284 case FFS_OS_DESC_EXT_COMPAT
: {
2285 struct usb_ext_compat_desc
*d
= data
;
2288 if (len
< sizeof(*d
) ||
2289 d
->bFirstInterfaceNumber
>= ffs
->interfaces_count
||
2292 for (i
= 0; i
< ARRAY_SIZE(d
->Reserved2
); ++i
)
2293 if (d
->Reserved2
[i
])
2296 length
= sizeof(struct usb_ext_compat_desc
);
2299 case FFS_OS_DESC_EXT_PROP
: {
2300 struct usb_ext_prop_desc
*d
= data
;
2304 if (len
< sizeof(*d
) || h
->interface
>= ffs
->interfaces_count
)
2306 length
= le32_to_cpu(d
->dwSize
);
2309 type
= le32_to_cpu(d
->dwPropertyDataType
);
2310 if (type
< USB_EXT_PROP_UNICODE
||
2311 type
> USB_EXT_PROP_UNICODE_MULTI
) {
2312 pr_vdebug("unsupported os descriptor property type: %d",
2316 pnl
= le16_to_cpu(d
->wPropertyNameLength
);
2317 if (length
< 14 + pnl
) {
2318 pr_vdebug("invalid os descriptor length: %d pnl:%d (descriptor %d)\n",
2322 pdl
= le32_to_cpu(*(u32
*)((u8
*)data
+ 10 + pnl
));
2323 if (length
!= 14 + pnl
+ pdl
) {
2324 pr_vdebug("invalid os descriptor length: %d pnl:%d pdl:%d (descriptor %d)\n",
2325 length
, pnl
, pdl
, type
);
2328 ++ffs
->ms_os_descs_ext_prop_count
;
2329 /* property name reported to the host as "WCHAR"s */
2330 ffs
->ms_os_descs_ext_prop_name_len
+= pnl
* 2;
2331 ffs
->ms_os_descs_ext_prop_data_len
+= pdl
;
2335 pr_vdebug("unknown descriptor: %d\n", type
);
2341 static int __ffs_data_got_descs(struct ffs_data
*ffs
,
2342 char *const _data
, size_t len
)
2344 char *data
= _data
, *raw_descs
;
2345 unsigned os_descs_count
= 0, counts
[3], flags
;
2346 int ret
= -EINVAL
, i
;
2347 struct ffs_desc_helper helper
;
2351 if (get_unaligned_le32(data
+ 4) != len
)
2354 switch (get_unaligned_le32(data
)) {
2355 case FUNCTIONFS_DESCRIPTORS_MAGIC
:
2356 flags
= FUNCTIONFS_HAS_FS_DESC
| FUNCTIONFS_HAS_HS_DESC
;
2360 case FUNCTIONFS_DESCRIPTORS_MAGIC_V2
:
2361 flags
= get_unaligned_le32(data
+ 8);
2362 ffs
->user_flags
= flags
;
2363 if (flags
& ~(FUNCTIONFS_HAS_FS_DESC
|
2364 FUNCTIONFS_HAS_HS_DESC
|
2365 FUNCTIONFS_HAS_SS_DESC
|
2366 FUNCTIONFS_HAS_MS_OS_DESC
|
2367 FUNCTIONFS_VIRTUAL_ADDR
|
2368 FUNCTIONFS_EVENTFD
|
2369 FUNCTIONFS_ALL_CTRL_RECIP
|
2370 FUNCTIONFS_CONFIG0_SETUP
)) {
2381 if (flags
& FUNCTIONFS_EVENTFD
) {
2385 eventfd_ctx_fdget((int)get_unaligned_le32(data
));
2386 if (IS_ERR(ffs
->ffs_eventfd
)) {
2387 ret
= PTR_ERR(ffs
->ffs_eventfd
);
2388 ffs
->ffs_eventfd
= NULL
;
2395 /* Read fs_count, hs_count and ss_count (if present) */
2396 for (i
= 0; i
< 3; ++i
) {
2397 if (!(flags
& (1 << i
))) {
2399 } else if (len
< 4) {
2402 counts
[i
] = get_unaligned_le32(data
);
2407 if (flags
& (1 << i
)) {
2411 os_descs_count
= get_unaligned_le32(data
);
2416 /* Read descriptors */
2419 for (i
= 0; i
< 3; ++i
) {
2422 helper
.interfaces_count
= 0;
2423 helper
.eps_count
= 0;
2424 ret
= ffs_do_descs(counts
[i
], data
, len
,
2425 __ffs_data_do_entity
, &helper
);
2428 if (!ffs
->eps_count
&& !ffs
->interfaces_count
) {
2429 ffs
->eps_count
= helper
.eps_count
;
2430 ffs
->interfaces_count
= helper
.interfaces_count
;
2432 if (ffs
->eps_count
!= helper
.eps_count
) {
2436 if (ffs
->interfaces_count
!= helper
.interfaces_count
) {
2444 if (os_descs_count
) {
2445 ret
= ffs_do_os_descs(os_descs_count
, data
, len
,
2446 __ffs_data_do_os_desc
, ffs
);
2453 if (raw_descs
== data
|| len
) {
2458 ffs
->raw_descs_data
= _data
;
2459 ffs
->raw_descs
= raw_descs
;
2460 ffs
->raw_descs_length
= data
- raw_descs
;
2461 ffs
->fs_descs_count
= counts
[0];
2462 ffs
->hs_descs_count
= counts
[1];
2463 ffs
->ss_descs_count
= counts
[2];
2464 ffs
->ms_os_descs_count
= os_descs_count
;
2473 static int __ffs_data_got_strings(struct ffs_data
*ffs
,
2474 char *const _data
, size_t len
)
2476 u32 str_count
, needed_count
, lang_count
;
2477 struct usb_gadget_strings
**stringtabs
, *t
;
2478 const char *data
= _data
;
2479 struct usb_string
*s
;
2483 if (unlikely(len
< 16 ||
2484 get_unaligned_le32(data
) != FUNCTIONFS_STRINGS_MAGIC
||
2485 get_unaligned_le32(data
+ 4) != len
))
2487 str_count
= get_unaligned_le32(data
+ 8);
2488 lang_count
= get_unaligned_le32(data
+ 12);
2490 /* if one is zero the other must be zero */
2491 if (unlikely(!str_count
!= !lang_count
))
2494 /* Do we have at least as many strings as descriptors need? */
2495 needed_count
= ffs
->strings_count
;
2496 if (unlikely(str_count
< needed_count
))
2500 * If we don't need any strings just return and free all
2503 if (!needed_count
) {
2508 /* Allocate everything in one chunk so there's less maintenance. */
2512 vla_item(d
, struct usb_gadget_strings
*, stringtabs
,
2514 vla_item(d
, struct usb_gadget_strings
, stringtab
, lang_count
);
2515 vla_item(d
, struct usb_string
, strings
,
2516 lang_count
*(needed_count
+1));
2518 char *vlabuf
= kmalloc(vla_group_size(d
), GFP_KERNEL
);
2520 if (unlikely(!vlabuf
)) {
2525 /* Initialize the VLA pointers */
2526 stringtabs
= vla_ptr(vlabuf
, d
, stringtabs
);
2527 t
= vla_ptr(vlabuf
, d
, stringtab
);
2530 *stringtabs
++ = t
++;
2534 /* stringtabs = vlabuf = d_stringtabs for later kfree */
2535 stringtabs
= vla_ptr(vlabuf
, d
, stringtabs
);
2536 t
= vla_ptr(vlabuf
, d
, stringtab
);
2537 s
= vla_ptr(vlabuf
, d
, strings
);
2540 /* For each language */
2544 do { /* lang_count > 0 so we can use do-while */
2545 unsigned needed
= needed_count
;
2547 if (unlikely(len
< 3))
2549 t
->language
= get_unaligned_le16(data
);
2556 /* For each string */
2557 do { /* str_count > 0 so we can use do-while */
2558 size_t length
= strnlen(data
, len
);
2560 if (unlikely(length
== len
))
2564 * User may provide more strings then we need,
2565 * if that's the case we simply ignore the
2568 if (likely(needed
)) {
2570 * s->id will be set while adding
2571 * function to configuration so for
2572 * now just leave garbage here.
2581 } while (--str_count
);
2583 s
->id
= 0; /* terminator */
2587 } while (--lang_count
);
2589 /* Some garbage left? */
2594 ffs
->stringtabs
= stringtabs
;
2595 ffs
->raw_strings
= _data
;
2607 /* Events handling and management *******************************************/
2609 static void __ffs_event_add(struct ffs_data
*ffs
,
2610 enum usb_functionfs_event_type type
)
2612 enum usb_functionfs_event_type rem_type1
, rem_type2
= type
;
2616 * Abort any unhandled setup
2618 * We do not need to worry about some cmpxchg() changing value
2619 * of ffs->setup_state without holding the lock because when
2620 * state is FFS_SETUP_PENDING cmpxchg() in several places in
2621 * the source does nothing.
2623 if (ffs
->setup_state
== FFS_SETUP_PENDING
)
2624 ffs
->setup_state
= FFS_SETUP_CANCELLED
;
2627 * Logic of this function guarantees that there are at most four pending
2628 * evens on ffs->ev.types queue. This is important because the queue
2629 * has space for four elements only and __ffs_ep0_read_events function
2630 * depends on that limit as well. If more event types are added, those
2631 * limits have to be revisited or guaranteed to still hold.
2634 case FUNCTIONFS_RESUME
:
2635 rem_type2
= FUNCTIONFS_SUSPEND
;
2637 case FUNCTIONFS_SUSPEND
:
2638 case FUNCTIONFS_SETUP
:
2640 /* Discard all similar events */
2643 case FUNCTIONFS_BIND
:
2644 case FUNCTIONFS_UNBIND
:
2645 case FUNCTIONFS_DISABLE
:
2646 case FUNCTIONFS_ENABLE
:
2647 /* Discard everything other then power management. */
2648 rem_type1
= FUNCTIONFS_SUSPEND
;
2649 rem_type2
= FUNCTIONFS_RESUME
;
2654 WARN(1, "%d: unknown event, this should not happen\n", type
);
2659 u8
*ev
= ffs
->ev
.types
, *out
= ev
;
2660 unsigned n
= ffs
->ev
.count
;
2661 for (; n
; --n
, ++ev
)
2662 if ((*ev
== rem_type1
|| *ev
== rem_type2
) == neg
)
2665 pr_vdebug("purging event %d\n", *ev
);
2666 ffs
->ev
.count
= out
- ffs
->ev
.types
;
2669 pr_vdebug("adding event %d\n", type
);
2670 ffs
->ev
.types
[ffs
->ev
.count
++] = type
;
2671 wake_up_locked(&ffs
->ev
.waitq
);
2672 if (ffs
->ffs_eventfd
)
2673 eventfd_signal(ffs
->ffs_eventfd
, 1);
2676 static void ffs_event_add(struct ffs_data
*ffs
,
2677 enum usb_functionfs_event_type type
)
2679 unsigned long flags
;
2680 spin_lock_irqsave(&ffs
->ev
.waitq
.lock
, flags
);
2681 __ffs_event_add(ffs
, type
);
2682 spin_unlock_irqrestore(&ffs
->ev
.waitq
.lock
, flags
);
2685 /* Bind/unbind USB function hooks *******************************************/
2687 static int ffs_ep_addr2idx(struct ffs_data
*ffs
, u8 endpoint_address
)
2691 for (i
= 1; i
< ARRAY_SIZE(ffs
->eps_addrmap
); ++i
)
2692 if (ffs
->eps_addrmap
[i
] == endpoint_address
)
2697 static int __ffs_func_bind_do_descs(enum ffs_entity_type type
, u8
*valuep
,
2698 struct usb_descriptor_header
*desc
,
2701 struct usb_endpoint_descriptor
*ds
= (void *)desc
;
2702 struct ffs_function
*func
= priv
;
2703 struct ffs_ep
*ffs_ep
;
2704 unsigned ep_desc_id
;
2706 static const char *speed_names
[] = { "full", "high", "super" };
2708 if (type
!= FFS_DESCRIPTOR
)
2712 * If ss_descriptors is not NULL, we are reading super speed
2713 * descriptors; if hs_descriptors is not NULL, we are reading high
2714 * speed descriptors; otherwise, we are reading full speed
2717 if (func
->function
.ss_descriptors
) {
2719 func
->function
.ss_descriptors
[(long)valuep
] = desc
;
2720 } else if (func
->function
.hs_descriptors
) {
2722 func
->function
.hs_descriptors
[(long)valuep
] = desc
;
2725 func
->function
.fs_descriptors
[(long)valuep
] = desc
;
2728 if (!desc
|| desc
->bDescriptorType
!= USB_DT_ENDPOINT
)
2731 idx
= ffs_ep_addr2idx(func
->ffs
, ds
->bEndpointAddress
) - 1;
2735 ffs_ep
= func
->eps
+ idx
;
2737 if (unlikely(ffs_ep
->descs
[ep_desc_id
])) {
2738 pr_err("two %sspeed descriptors for EP %d\n",
2739 speed_names
[ep_desc_id
],
2740 ds
->bEndpointAddress
& USB_ENDPOINT_NUMBER_MASK
);
2743 ffs_ep
->descs
[ep_desc_id
] = ds
;
2745 ffs_dump_mem(": Original ep desc", ds
, ds
->bLength
);
2747 ds
->bEndpointAddress
= ffs_ep
->descs
[0]->bEndpointAddress
;
2748 if (!ds
->wMaxPacketSize
)
2749 ds
->wMaxPacketSize
= ffs_ep
->descs
[0]->wMaxPacketSize
;
2751 struct usb_request
*req
;
2753 u8 bEndpointAddress
;
2756 * We back up bEndpointAddress because autoconfig overwrites
2757 * it with physical endpoint address.
2759 bEndpointAddress
= ds
->bEndpointAddress
;
2760 pr_vdebug("autoconfig\n");
2761 ep
= usb_ep_autoconfig(func
->gadget
, ds
);
2764 ep
->driver_data
= func
->eps
+ idx
;
2766 req
= usb_ep_alloc_request(ep
, GFP_KERNEL
);
2772 func
->eps_revmap
[ds
->bEndpointAddress
&
2773 USB_ENDPOINT_NUMBER_MASK
] = idx
+ 1;
2775 * If we use virtual address mapping, we restore
2776 * original bEndpointAddress value.
2778 if (func
->ffs
->user_flags
& FUNCTIONFS_VIRTUAL_ADDR
)
2779 ds
->bEndpointAddress
= bEndpointAddress
;
2781 ffs_dump_mem(": Rewritten ep desc", ds
, ds
->bLength
);
2786 static int __ffs_func_bind_do_nums(enum ffs_entity_type type
, u8
*valuep
,
2787 struct usb_descriptor_header
*desc
,
2790 struct ffs_function
*func
= priv
;
2796 case FFS_DESCRIPTOR
:
2797 /* Handled in previous pass by __ffs_func_bind_do_descs() */
2802 if (func
->interfaces_nums
[idx
] < 0) {
2803 int id
= usb_interface_id(func
->conf
, &func
->function
);
2804 if (unlikely(id
< 0))
2806 func
->interfaces_nums
[idx
] = id
;
2808 newValue
= func
->interfaces_nums
[idx
];
2812 /* String' IDs are allocated when fsf_data is bound to cdev */
2813 newValue
= func
->ffs
->stringtabs
[0]->strings
[*valuep
- 1].id
;
2818 * USB_DT_ENDPOINT are handled in
2819 * __ffs_func_bind_do_descs().
2821 if (desc
->bDescriptorType
== USB_DT_ENDPOINT
)
2824 idx
= (*valuep
& USB_ENDPOINT_NUMBER_MASK
) - 1;
2825 if (unlikely(!func
->eps
[idx
].ep
))
2829 struct usb_endpoint_descriptor
**descs
;
2830 descs
= func
->eps
[idx
].descs
;
2831 newValue
= descs
[descs
[0] ? 0 : 1]->bEndpointAddress
;
2836 pr_vdebug("%02x -> %02x\n", *valuep
, newValue
);
2841 static int __ffs_func_bind_do_os_desc(enum ffs_os_desc_type type
,
2842 struct usb_os_desc_header
*h
, void *data
,
2843 unsigned len
, void *priv
)
2845 struct ffs_function
*func
= priv
;
2849 case FFS_OS_DESC_EXT_COMPAT
: {
2850 struct usb_ext_compat_desc
*desc
= data
;
2851 struct usb_os_desc_table
*t
;
2853 t
= &func
->function
.os_desc_table
[desc
->bFirstInterfaceNumber
];
2854 t
->if_id
= func
->interfaces_nums
[desc
->bFirstInterfaceNumber
];
2855 memcpy(t
->os_desc
->ext_compat_id
, &desc
->CompatibleID
,
2856 ARRAY_SIZE(desc
->CompatibleID
) +
2857 ARRAY_SIZE(desc
->SubCompatibleID
));
2858 length
= sizeof(*desc
);
2861 case FFS_OS_DESC_EXT_PROP
: {
2862 struct usb_ext_prop_desc
*desc
= data
;
2863 struct usb_os_desc_table
*t
;
2864 struct usb_os_desc_ext_prop
*ext_prop
;
2865 char *ext_prop_name
;
2866 char *ext_prop_data
;
2868 t
= &func
->function
.os_desc_table
[h
->interface
];
2869 t
->if_id
= func
->interfaces_nums
[h
->interface
];
2871 ext_prop
= func
->ffs
->ms_os_descs_ext_prop_avail
;
2872 func
->ffs
->ms_os_descs_ext_prop_avail
+= sizeof(*ext_prop
);
2874 ext_prop
->type
= le32_to_cpu(desc
->dwPropertyDataType
);
2875 ext_prop
->name_len
= le16_to_cpu(desc
->wPropertyNameLength
);
2876 ext_prop
->data_len
= le32_to_cpu(*(u32
*)
2877 usb_ext_prop_data_len_ptr(data
, ext_prop
->name_len
));
2878 length
= ext_prop
->name_len
+ ext_prop
->data_len
+ 14;
2880 ext_prop_name
= func
->ffs
->ms_os_descs_ext_prop_name_avail
;
2881 func
->ffs
->ms_os_descs_ext_prop_name_avail
+=
2884 ext_prop_data
= func
->ffs
->ms_os_descs_ext_prop_data_avail
;
2885 func
->ffs
->ms_os_descs_ext_prop_data_avail
+=
2887 memcpy(ext_prop_data
,
2888 usb_ext_prop_data_ptr(data
, ext_prop
->name_len
),
2889 ext_prop
->data_len
);
2890 /* unicode data reported to the host as "WCHAR"s */
2891 switch (ext_prop
->type
) {
2892 case USB_EXT_PROP_UNICODE
:
2893 case USB_EXT_PROP_UNICODE_ENV
:
2894 case USB_EXT_PROP_UNICODE_LINK
:
2895 case USB_EXT_PROP_UNICODE_MULTI
:
2896 ext_prop
->data_len
*= 2;
2899 ext_prop
->data
= ext_prop_data
;
2901 memcpy(ext_prop_name
, usb_ext_prop_name_ptr(data
),
2902 ext_prop
->name_len
);
2903 /* property name reported to the host as "WCHAR"s */
2904 ext_prop
->name_len
*= 2;
2905 ext_prop
->name
= ext_prop_name
;
2907 t
->os_desc
->ext_prop_len
+=
2908 ext_prop
->name_len
+ ext_prop
->data_len
+ 14;
2909 ++t
->os_desc
->ext_prop_count
;
2910 list_add_tail(&ext_prop
->entry
, &t
->os_desc
->ext_prop
);
2914 pr_vdebug("unknown descriptor: %d\n", type
);
2920 static inline struct f_fs_opts
*ffs_do_functionfs_bind(struct usb_function
*f
,
2921 struct usb_configuration
*c
)
2923 struct ffs_function
*func
= ffs_func_from_usb(f
);
2924 struct f_fs_opts
*ffs_opts
=
2925 container_of(f
->fi
, struct f_fs_opts
, func_inst
);
2931 * Legacy gadget triggers binding in functionfs_ready_callback,
2932 * which already uses locking; taking the same lock here would
2935 * Configfs-enabled gadgets however do need ffs_dev_lock.
2937 if (!ffs_opts
->no_configfs
)
2939 ret
= ffs_opts
->dev
->desc_ready
? 0 : -ENODEV
;
2940 func
->ffs
= ffs_opts
->dev
->ffs_data
;
2941 if (!ffs_opts
->no_configfs
)
2944 return ERR_PTR(ret
);
2947 func
->gadget
= c
->cdev
->gadget
;
2950 * in drivers/usb/gadget/configfs.c:configfs_composite_bind()
2951 * configurations are bound in sequence with list_for_each_entry,
2952 * in each configuration its functions are bound in sequence
2953 * with list_for_each_entry, so we assume no race condition
2954 * with regard to ffs_opts->bound access
2956 if (!ffs_opts
->refcnt
) {
2957 ret
= functionfs_bind(func
->ffs
, c
->cdev
);
2959 return ERR_PTR(ret
);
2962 func
->function
.strings
= func
->ffs
->stringtabs
;
2967 static int _ffs_func_bind(struct usb_configuration
*c
,
2968 struct usb_function
*f
)
2970 struct ffs_function
*func
= ffs_func_from_usb(f
);
2971 struct ffs_data
*ffs
= func
->ffs
;
2973 const int full
= !!func
->ffs
->fs_descs_count
;
2974 const int high
= gadget_is_dualspeed(func
->gadget
) &&
2975 func
->ffs
->hs_descs_count
;
2976 const int super
= gadget_is_superspeed(func
->gadget
) &&
2977 func
->ffs
->ss_descs_count
;
2979 int fs_len
, hs_len
, ss_len
, ret
, i
;
2980 struct ffs_ep
*eps_ptr
;
2982 /* Make it a single chunk, less management later on */
2984 vla_item_with_sz(d
, struct ffs_ep
, eps
, ffs
->eps_count
);
2985 vla_item_with_sz(d
, struct usb_descriptor_header
*, fs_descs
,
2986 full
? ffs
->fs_descs_count
+ 1 : 0);
2987 vla_item_with_sz(d
, struct usb_descriptor_header
*, hs_descs
,
2988 high
? ffs
->hs_descs_count
+ 1 : 0);
2989 vla_item_with_sz(d
, struct usb_descriptor_header
*, ss_descs
,
2990 super
? ffs
->ss_descs_count
+ 1 : 0);
2991 vla_item_with_sz(d
, short, inums
, ffs
->interfaces_count
);
2992 vla_item_with_sz(d
, struct usb_os_desc_table
, os_desc_table
,
2993 c
->cdev
->use_os_string
? ffs
->interfaces_count
: 0);
2994 vla_item_with_sz(d
, char[16], ext_compat
,
2995 c
->cdev
->use_os_string
? ffs
->interfaces_count
: 0);
2996 vla_item_with_sz(d
, struct usb_os_desc
, os_desc
,
2997 c
->cdev
->use_os_string
? ffs
->interfaces_count
: 0);
2998 vla_item_with_sz(d
, struct usb_os_desc_ext_prop
, ext_prop
,
2999 ffs
->ms_os_descs_ext_prop_count
);
3000 vla_item_with_sz(d
, char, ext_prop_name
,
3001 ffs
->ms_os_descs_ext_prop_name_len
);
3002 vla_item_with_sz(d
, char, ext_prop_data
,
3003 ffs
->ms_os_descs_ext_prop_data_len
);
3004 vla_item_with_sz(d
, char, raw_descs
, ffs
->raw_descs_length
);
3009 /* Has descriptors only for speeds gadget does not support */
3010 if (unlikely(!(full
| high
| super
)))
3013 /* Allocate a single chunk, less management later on */
3014 vlabuf
= kzalloc(vla_group_size(d
), GFP_KERNEL
);
3015 if (unlikely(!vlabuf
))
3018 ffs
->ms_os_descs_ext_prop_avail
= vla_ptr(vlabuf
, d
, ext_prop
);
3019 ffs
->ms_os_descs_ext_prop_name_avail
=
3020 vla_ptr(vlabuf
, d
, ext_prop_name
);
3021 ffs
->ms_os_descs_ext_prop_data_avail
=
3022 vla_ptr(vlabuf
, d
, ext_prop_data
);
3024 /* Copy descriptors */
3025 memcpy(vla_ptr(vlabuf
, d
, raw_descs
), ffs
->raw_descs
,
3026 ffs
->raw_descs_length
);
3028 memset(vla_ptr(vlabuf
, d
, inums
), 0xff, d_inums__sz
);
3029 eps_ptr
= vla_ptr(vlabuf
, d
, eps
);
3030 for (i
= 0; i
< ffs
->eps_count
; i
++)
3031 eps_ptr
[i
].num
= -1;
3034 * d_eps == vlabuf, func->eps used to kfree vlabuf later
3036 func
->eps
= vla_ptr(vlabuf
, d
, eps
);
3037 func
->interfaces_nums
= vla_ptr(vlabuf
, d
, inums
);
3040 * Go through all the endpoint descriptors and allocate
3041 * endpoints first, so that later we can rewrite the endpoint
3042 * numbers without worrying that it may be described later on.
3045 func
->function
.fs_descriptors
= vla_ptr(vlabuf
, d
, fs_descs
);
3046 fs_len
= ffs_do_descs(ffs
->fs_descs_count
,
3047 vla_ptr(vlabuf
, d
, raw_descs
),
3049 __ffs_func_bind_do_descs
, func
);
3050 if (unlikely(fs_len
< 0)) {
3059 func
->function
.hs_descriptors
= vla_ptr(vlabuf
, d
, hs_descs
);
3060 hs_len
= ffs_do_descs(ffs
->hs_descs_count
,
3061 vla_ptr(vlabuf
, d
, raw_descs
) + fs_len
,
3062 d_raw_descs__sz
- fs_len
,
3063 __ffs_func_bind_do_descs
, func
);
3064 if (unlikely(hs_len
< 0)) {
3072 if (likely(super
)) {
3073 func
->function
.ss_descriptors
= vla_ptr(vlabuf
, d
, ss_descs
);
3074 ss_len
= ffs_do_descs(ffs
->ss_descs_count
,
3075 vla_ptr(vlabuf
, d
, raw_descs
) + fs_len
+ hs_len
,
3076 d_raw_descs__sz
- fs_len
- hs_len
,
3077 __ffs_func_bind_do_descs
, func
);
3078 if (unlikely(ss_len
< 0)) {
3087 * Now handle interface numbers allocation and interface and
3088 * endpoint numbers rewriting. We can do that in one go
3091 ret
= ffs_do_descs(ffs
->fs_descs_count
+
3092 (high
? ffs
->hs_descs_count
: 0) +
3093 (super
? ffs
->ss_descs_count
: 0),
3094 vla_ptr(vlabuf
, d
, raw_descs
), d_raw_descs__sz
,
3095 __ffs_func_bind_do_nums
, func
);
3096 if (unlikely(ret
< 0))
3099 func
->function
.os_desc_table
= vla_ptr(vlabuf
, d
, os_desc_table
);
3100 if (c
->cdev
->use_os_string
) {
3101 for (i
= 0; i
< ffs
->interfaces_count
; ++i
) {
3102 struct usb_os_desc
*desc
;
3104 desc
= func
->function
.os_desc_table
[i
].os_desc
=
3105 vla_ptr(vlabuf
, d
, os_desc
) +
3106 i
* sizeof(struct usb_os_desc
);
3107 desc
->ext_compat_id
=
3108 vla_ptr(vlabuf
, d
, ext_compat
) + i
* 16;
3109 INIT_LIST_HEAD(&desc
->ext_prop
);
3111 ret
= ffs_do_os_descs(ffs
->ms_os_descs_count
,
3112 vla_ptr(vlabuf
, d
, raw_descs
) +
3113 fs_len
+ hs_len
+ ss_len
,
3114 d_raw_descs__sz
- fs_len
- hs_len
-
3116 __ffs_func_bind_do_os_desc
, func
);
3117 if (unlikely(ret
< 0))
3120 func
->function
.os_desc_n
=
3121 c
->cdev
->use_os_string
? ffs
->interfaces_count
: 0;
3123 /* And we're done */
3124 ffs_event_add(ffs
, FUNCTIONFS_BIND
);
3128 /* XXX Do we need to release all claimed endpoints here? */
3132 static int ffs_func_bind(struct usb_configuration
*c
,
3133 struct usb_function
*f
)
3135 struct f_fs_opts
*ffs_opts
= ffs_do_functionfs_bind(f
, c
);
3136 struct ffs_function
*func
= ffs_func_from_usb(f
);
3139 if (IS_ERR(ffs_opts
))
3140 return PTR_ERR(ffs_opts
);
3142 ret
= _ffs_func_bind(c
, f
);
3143 if (ret
&& !--ffs_opts
->refcnt
)
3144 functionfs_unbind(func
->ffs
);
3150 /* Other USB function hooks *************************************************/
3152 static void ffs_reset_work(struct work_struct
*work
)
3154 struct ffs_data
*ffs
= container_of(work
,
3155 struct ffs_data
, reset_work
);
3156 ffs_data_reset(ffs
);
3159 static int ffs_func_set_alt(struct usb_function
*f
,
3160 unsigned interface
, unsigned alt
)
3162 struct ffs_function
*func
= ffs_func_from_usb(f
);
3163 struct ffs_data
*ffs
= func
->ffs
;
3166 if (alt
!= (unsigned)-1) {
3167 intf
= ffs_func_revmap_intf(func
, interface
);
3168 if (unlikely(intf
< 0))
3173 ffs_func_eps_disable(ffs
->func
);
3175 if (ffs
->state
== FFS_DEACTIVATED
) {
3176 ffs
->state
= FFS_CLOSING
;
3177 INIT_WORK(&ffs
->reset_work
, ffs_reset_work
);
3178 schedule_work(&ffs
->reset_work
);
3182 if (ffs
->state
!= FFS_ACTIVE
)
3185 if (alt
== (unsigned)-1) {
3187 ffs_event_add(ffs
, FUNCTIONFS_DISABLE
);
3192 ret
= ffs_func_eps_enable(func
);
3193 if (likely(ret
>= 0))
3194 ffs_event_add(ffs
, FUNCTIONFS_ENABLE
);
3198 static void ffs_func_disable(struct usb_function
*f
)
3200 ffs_func_set_alt(f
, 0, (unsigned)-1);
3203 static int ffs_func_setup(struct usb_function
*f
,
3204 const struct usb_ctrlrequest
*creq
)
3206 struct ffs_function
*func
= ffs_func_from_usb(f
);
3207 struct ffs_data
*ffs
= func
->ffs
;
3208 unsigned long flags
;
3213 pr_vdebug("creq->bRequestType = %02x\n", creq
->bRequestType
);
3214 pr_vdebug("creq->bRequest = %02x\n", creq
->bRequest
);
3215 pr_vdebug("creq->wValue = %04x\n", le16_to_cpu(creq
->wValue
));
3216 pr_vdebug("creq->wIndex = %04x\n", le16_to_cpu(creq
->wIndex
));
3217 pr_vdebug("creq->wLength = %04x\n", le16_to_cpu(creq
->wLength
));
3220 * Most requests directed to interface go through here
3221 * (notable exceptions are set/get interface) so we need to
3222 * handle them. All other either handled by composite or
3223 * passed to usb_configuration->setup() (if one is set). No
3224 * matter, we will handle requests directed to endpoint here
3225 * as well (as it's straightforward). Other request recipient
3226 * types are only handled when the user flag FUNCTIONFS_ALL_CTRL_RECIP
3229 if (ffs
->state
!= FFS_ACTIVE
)
3232 switch (creq
->bRequestType
& USB_RECIP_MASK
) {
3233 case USB_RECIP_INTERFACE
:
3234 ret
= ffs_func_revmap_intf(func
, le16_to_cpu(creq
->wIndex
));
3235 if (unlikely(ret
< 0))
3239 case USB_RECIP_ENDPOINT
:
3240 ret
= ffs_func_revmap_ep(func
, le16_to_cpu(creq
->wIndex
));
3241 if (unlikely(ret
< 0))
3243 if (func
->ffs
->user_flags
& FUNCTIONFS_VIRTUAL_ADDR
)
3244 ret
= func
->ffs
->eps_addrmap
[ret
];
3248 if (func
->ffs
->user_flags
& FUNCTIONFS_ALL_CTRL_RECIP
)
3249 ret
= le16_to_cpu(creq
->wIndex
);
3254 spin_lock_irqsave(&ffs
->ev
.waitq
.lock
, flags
);
3255 ffs
->ev
.setup
= *creq
;
3256 ffs
->ev
.setup
.wIndex
= cpu_to_le16(ret
);
3257 __ffs_event_add(ffs
, FUNCTIONFS_SETUP
);
3258 spin_unlock_irqrestore(&ffs
->ev
.waitq
.lock
, flags
);
3263 static bool ffs_func_req_match(struct usb_function
*f
,
3264 const struct usb_ctrlrequest
*creq
,
3267 struct ffs_function
*func
= ffs_func_from_usb(f
);
3269 if (config0
&& !(func
->ffs
->user_flags
& FUNCTIONFS_CONFIG0_SETUP
))
3272 switch (creq
->bRequestType
& USB_RECIP_MASK
) {
3273 case USB_RECIP_INTERFACE
:
3274 return (ffs_func_revmap_intf(func
,
3275 le16_to_cpu(creq
->wIndex
)) >= 0);
3276 case USB_RECIP_ENDPOINT
:
3277 return (ffs_func_revmap_ep(func
,
3278 le16_to_cpu(creq
->wIndex
)) >= 0);
3280 return (bool) (func
->ffs
->user_flags
&
3281 FUNCTIONFS_ALL_CTRL_RECIP
);
3285 static void ffs_func_suspend(struct usb_function
*f
)
3288 ffs_event_add(ffs_func_from_usb(f
)->ffs
, FUNCTIONFS_SUSPEND
);
3291 static void ffs_func_resume(struct usb_function
*f
)
3294 ffs_event_add(ffs_func_from_usb(f
)->ffs
, FUNCTIONFS_RESUME
);
3298 /* Endpoint and interface numbers reverse mapping ***************************/
3300 static int ffs_func_revmap_ep(struct ffs_function
*func
, u8 num
)
3302 num
= func
->eps_revmap
[num
& USB_ENDPOINT_NUMBER_MASK
];
3303 return num
? num
: -EDOM
;
3306 static int ffs_func_revmap_intf(struct ffs_function
*func
, u8 intf
)
3308 short *nums
= func
->interfaces_nums
;
3309 unsigned count
= func
->ffs
->interfaces_count
;
3311 for (; count
; --count
, ++nums
) {
3312 if (*nums
>= 0 && *nums
== intf
)
3313 return nums
- func
->interfaces_nums
;
3320 /* Devices management *******************************************************/
3322 static LIST_HEAD(ffs_devices
);
3324 static struct ffs_dev
*_ffs_do_find_dev(const char *name
)
3326 struct ffs_dev
*dev
;
3331 list_for_each_entry(dev
, &ffs_devices
, entry
) {
3332 if (strcmp(dev
->name
, name
) == 0)
3340 * ffs_lock must be taken by the caller of this function
3342 static struct ffs_dev
*_ffs_get_single_dev(void)
3344 struct ffs_dev
*dev
;
3346 if (list_is_singular(&ffs_devices
)) {
3347 dev
= list_first_entry(&ffs_devices
, struct ffs_dev
, entry
);
3356 * ffs_lock must be taken by the caller of this function
3358 static struct ffs_dev
*_ffs_find_dev(const char *name
)
3360 struct ffs_dev
*dev
;
3362 dev
= _ffs_get_single_dev();
3366 return _ffs_do_find_dev(name
);
3369 /* Configfs support *********************************************************/
3371 static inline struct f_fs_opts
*to_ffs_opts(struct config_item
*item
)
3373 return container_of(to_config_group(item
), struct f_fs_opts
,
3377 static void ffs_attr_release(struct config_item
*item
)
3379 struct f_fs_opts
*opts
= to_ffs_opts(item
);
3381 usb_put_function_instance(&opts
->func_inst
);
3384 static struct configfs_item_operations ffs_item_ops
= {
3385 .release
= ffs_attr_release
,
3388 static struct config_item_type ffs_func_type
= {
3389 .ct_item_ops
= &ffs_item_ops
,
3390 .ct_owner
= THIS_MODULE
,
3394 /* Function registration interface ******************************************/
3396 static void ffs_free_inst(struct usb_function_instance
*f
)
3398 struct f_fs_opts
*opts
;
3400 opts
= to_f_fs_opts(f
);
3402 _ffs_free_dev(opts
->dev
);
3407 static int ffs_set_inst_name(struct usb_function_instance
*fi
, const char *name
)
3409 if (strlen(name
) >= FIELD_SIZEOF(struct ffs_dev
, name
))
3410 return -ENAMETOOLONG
;
3411 return ffs_name_dev(to_f_fs_opts(fi
)->dev
, name
);
3414 static struct usb_function_instance
*ffs_alloc_inst(void)
3416 struct f_fs_opts
*opts
;
3417 struct ffs_dev
*dev
;
3419 opts
= kzalloc(sizeof(*opts
), GFP_KERNEL
);
3421 return ERR_PTR(-ENOMEM
);
3423 opts
->func_inst
.set_inst_name
= ffs_set_inst_name
;
3424 opts
->func_inst
.free_func_inst
= ffs_free_inst
;
3426 dev
= _ffs_alloc_dev();
3430 return ERR_CAST(dev
);
3435 config_group_init_type_name(&opts
->func_inst
.group
, "",
3437 return &opts
->func_inst
;
3440 static void ffs_free(struct usb_function
*f
)
3442 kfree(ffs_func_from_usb(f
));
3445 static void ffs_func_unbind(struct usb_configuration
*c
,
3446 struct usb_function
*f
)
3448 struct ffs_function
*func
= ffs_func_from_usb(f
);
3449 struct ffs_data
*ffs
= func
->ffs
;
3450 struct f_fs_opts
*opts
=
3451 container_of(f
->fi
, struct f_fs_opts
, func_inst
);
3452 struct ffs_ep
*ep
= func
->eps
;
3453 unsigned count
= ffs
->eps_count
;
3454 unsigned long flags
;
3457 if (ffs
->func
== func
) {
3458 ffs_func_eps_disable(func
);
3462 if (!--opts
->refcnt
)
3463 functionfs_unbind(ffs
);
3465 /* cleanup after autoconfig */
3466 spin_lock_irqsave(&func
->ffs
->eps_lock
, flags
);
3468 if (ep
->ep
&& ep
->req
)
3469 usb_ep_free_request(ep
->ep
, ep
->req
);
3473 spin_unlock_irqrestore(&func
->ffs
->eps_lock
, flags
);
3477 * eps, descriptors and interfaces_nums are allocated in the
3478 * same chunk so only one free is required.
3480 func
->function
.fs_descriptors
= NULL
;
3481 func
->function
.hs_descriptors
= NULL
;
3482 func
->function
.ss_descriptors
= NULL
;
3483 func
->interfaces_nums
= NULL
;
3485 ffs_event_add(ffs
, FUNCTIONFS_UNBIND
);
3488 static struct usb_function
*ffs_alloc(struct usb_function_instance
*fi
)
3490 struct ffs_function
*func
;
3494 func
= kzalloc(sizeof(*func
), GFP_KERNEL
);
3495 if (unlikely(!func
))
3496 return ERR_PTR(-ENOMEM
);
3498 func
->function
.name
= "Function FS Gadget";
3500 func
->function
.bind
= ffs_func_bind
;
3501 func
->function
.unbind
= ffs_func_unbind
;
3502 func
->function
.set_alt
= ffs_func_set_alt
;
3503 func
->function
.disable
= ffs_func_disable
;
3504 func
->function
.setup
= ffs_func_setup
;
3505 func
->function
.req_match
= ffs_func_req_match
;
3506 func
->function
.suspend
= ffs_func_suspend
;
3507 func
->function
.resume
= ffs_func_resume
;
3508 func
->function
.free_func
= ffs_free
;
3510 return &func
->function
;
3514 * ffs_lock must be taken by the caller of this function
3516 static struct ffs_dev
*_ffs_alloc_dev(void)
3518 struct ffs_dev
*dev
;
3521 if (_ffs_get_single_dev())
3522 return ERR_PTR(-EBUSY
);
3524 dev
= kzalloc(sizeof(*dev
), GFP_KERNEL
);
3526 return ERR_PTR(-ENOMEM
);
3528 if (list_empty(&ffs_devices
)) {
3529 ret
= functionfs_init();
3532 return ERR_PTR(ret
);
3536 list_add(&dev
->entry
, &ffs_devices
);
3541 int ffs_name_dev(struct ffs_dev
*dev
, const char *name
)
3543 struct ffs_dev
*existing
;
3548 existing
= _ffs_do_find_dev(name
);
3550 strlcpy(dev
->name
, name
, ARRAY_SIZE(dev
->name
));
3551 else if (existing
!= dev
)
3558 EXPORT_SYMBOL_GPL(ffs_name_dev
);
3560 int ffs_single_dev(struct ffs_dev
*dev
)
3567 if (!list_is_singular(&ffs_devices
))
3575 EXPORT_SYMBOL_GPL(ffs_single_dev
);
3578 * ffs_lock must be taken by the caller of this function
3580 static void _ffs_free_dev(struct ffs_dev
*dev
)
3582 list_del(&dev
->entry
);
3584 /* Clear the private_data pointer to stop incorrect dev access */
3586 dev
->ffs_data
->private_data
= NULL
;
3589 if (list_empty(&ffs_devices
))
3590 functionfs_cleanup();
3593 static void *ffs_acquire_dev(const char *dev_name
)
3595 struct ffs_dev
*ffs_dev
;
3600 ffs_dev
= _ffs_find_dev(dev_name
);
3602 ffs_dev
= ERR_PTR(-ENOENT
);
3603 else if (ffs_dev
->mounted
)
3604 ffs_dev
= ERR_PTR(-EBUSY
);
3605 else if (ffs_dev
->ffs_acquire_dev_callback
&&
3606 ffs_dev
->ffs_acquire_dev_callback(ffs_dev
))
3607 ffs_dev
= ERR_PTR(-ENOENT
);
3609 ffs_dev
->mounted
= true;
3615 static void ffs_release_dev(struct ffs_data
*ffs_data
)
3617 struct ffs_dev
*ffs_dev
;
3622 ffs_dev
= ffs_data
->private_data
;
3624 ffs_dev
->mounted
= false;
3626 if (ffs_dev
->ffs_release_dev_callback
)
3627 ffs_dev
->ffs_release_dev_callback(ffs_dev
);
3633 static int ffs_ready(struct ffs_data
*ffs
)
3635 struct ffs_dev
*ffs_obj
;
3641 ffs_obj
= ffs
->private_data
;
3646 if (WARN_ON(ffs_obj
->desc_ready
)) {
3651 ffs_obj
->desc_ready
= true;
3652 ffs_obj
->ffs_data
= ffs
;
3654 if (ffs_obj
->ffs_ready_callback
) {
3655 ret
= ffs_obj
->ffs_ready_callback(ffs
);
3660 set_bit(FFS_FL_CALL_CLOSED_CALLBACK
, &ffs
->flags
);
3666 static void ffs_closed(struct ffs_data
*ffs
)
3668 struct ffs_dev
*ffs_obj
;
3669 struct f_fs_opts
*opts
;
3670 struct config_item
*ci
;
3675 ffs_obj
= ffs
->private_data
;
3679 ffs_obj
->desc_ready
= false;
3681 if (test_and_clear_bit(FFS_FL_CALL_CLOSED_CALLBACK
, &ffs
->flags
) &&
3682 ffs_obj
->ffs_closed_callback
)
3683 ffs_obj
->ffs_closed_callback(ffs
);
3686 opts
= ffs_obj
->opts
;
3690 if (opts
->no_configfs
|| !opts
->func_inst
.group
.cg_item
.ci_parent
3691 || !kref_read(&opts
->func_inst
.group
.cg_item
.ci_kref
))
3694 ci
= opts
->func_inst
.group
.cg_item
.ci_parent
->ci_parent
;
3697 unregister_gadget_item(ci
);
3703 /* Misc helper functions ****************************************************/
3705 static int ffs_mutex_lock(struct mutex
*mutex
, unsigned nonblock
)
3708 ? likely(mutex_trylock(mutex
)) ? 0 : -EAGAIN
3709 : mutex_lock_interruptible(mutex
);
3712 static char *ffs_prepare_buffer(const char __user
*buf
, size_t len
)
3719 data
= kmalloc(len
, GFP_KERNEL
);
3720 if (unlikely(!data
))
3721 return ERR_PTR(-ENOMEM
);
3723 if (unlikely(copy_from_user(data
, buf
, len
))) {
3725 return ERR_PTR(-EFAULT
);
3728 pr_vdebug("Buffer from user space:\n");
3729 ffs_dump_mem("", data
, len
);
3734 DECLARE_USB_FUNCTION_INIT(ffs
, ffs_alloc_inst
, ffs_alloc
);
3735 MODULE_LICENSE("GPL");
3736 MODULE_AUTHOR("Michal Nazarewicz");