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 <asm/unaligned.h>
27 #include <linux/usb/composite.h>
28 #include <linux/usb/functionfs.h>
31 #define FUNCTIONFS_MAGIC 0xa647361 /* Chosen by a honest dice roll ;) */
34 /* Debugging ****************************************************************/
38 # define pr_vdebug pr_debug
39 #endif /* pr_vdebug */
40 # define ffs_dump_mem(prefix, ptr, len) \
41 print_hex_dump_bytes(pr_fmt(prefix ": "), DUMP_PREFIX_NONE, ptr, len)
44 # define pr_vdebug(...) do { } while (0)
45 #endif /* pr_vdebug */
46 # define ffs_dump_mem(prefix, ptr, len) do { } while (0)
47 #endif /* VERBOSE_DEBUG */
49 #define ENTER() pr_vdebug("%s()\n", __func__)
52 /* The data structure and setup file ****************************************/
56 * Waiting for descriptors and strings.
58 * In this state no open(2), read(2) or write(2) on epfiles
59 * may succeed (which should not be the problem as there
60 * should be no such files opened in the first place).
66 * We've got descriptors and strings. We are or have called
67 * functionfs_ready_callback(). functionfs_bind() may have
68 * been called but we don't know.
70 * This is the only state in which operations on epfiles may
76 * All endpoints have been closed. This state is also set if
77 * we encounter an unrecoverable error. The only
78 * unrecoverable error is situation when after reading strings
79 * from user space we fail to initialise epfiles or
80 * functionfs_ready_callback() returns with error (<0).
82 * In this state no open(2), read(2) or write(2) (both on ep0
83 * as well as epfile) may succeed (at this point epfiles are
84 * unlinked and all closed so this is not a problem; ep0 is
85 * also closed but ep0 file exists and so open(2) on ep0 must
92 enum ffs_setup_state
{
93 /* There is no setup request pending. */
96 * User has read events and there was a setup request event
97 * there. The next read/write on ep0 will handle the
102 * There was event pending but before user space handled it
103 * some other event was introduced which canceled existing
104 * setup. If this state is set read/write on ep0 return
105 * -EIDRM. This state is only set when adding event.
116 struct usb_gadget
*gadget
;
119 * Protect access read/write operations, only one read/write
120 * at a time. As a consequence protects ep0req and company.
121 * While setup request is being processed (queued) this is
127 * Protect access to endpoint related structures (basically
128 * usb_ep_queue(), usb_ep_dequeue(), etc. calls) except for
134 * XXX REVISIT do we need our own request? Since we are not
135 * handling setup requests immediately user space may be so
136 * slow that another setup will be sent to the gadget but this
137 * time not to us but another function and then there could be
138 * a race. Is that the case? Or maybe we can use cdev->req
139 * after all, maybe we just need some spinlock for that?
141 struct usb_request
*ep0req
; /* P: mutex */
142 struct completion ep0req_completion
; /* P: mutex */
143 int ep0req_status
; /* P: mutex */
145 /* reference counter */
147 /* how many files are opened (EP0 and others) */
151 enum ffs_state state
;
154 * Possible transitions:
155 * + FFS_NO_SETUP -> FFS_SETUP_PENDING -- P: ev.waitq.lock
156 * happens only in ep0 read which is P: mutex
157 * + FFS_SETUP_PENDING -> FFS_NO_SETUP -- P: ev.waitq.lock
158 * happens only in ep0 i/o which is P: mutex
159 * + FFS_SETUP_PENDING -> FFS_SETUP_CANCELED -- P: ev.waitq.lock
160 * + FFS_SETUP_CANCELED -> FFS_NO_SETUP -- cmpxchg
162 enum ffs_setup_state setup_state
;
164 #define FFS_SETUP_STATE(ffs) \
165 ((enum ffs_setup_state)cmpxchg(&(ffs)->setup_state, \
166 FFS_SETUP_CANCELED, FFS_NO_SETUP))
171 unsigned short count
;
172 /* XXX REVISIT need to update it in some places, or do we? */
173 unsigned short can_stall
;
174 struct usb_ctrlrequest setup
;
176 wait_queue_head_t waitq
;
177 } ev
; /* the whole structure, P: ev.waitq.lock */
181 #define FFS_FL_CALL_CLOSED_CALLBACK 0
182 #define FFS_FL_BOUND 1
184 /* Active function */
185 struct ffs_function
*func
;
188 * Device name, write once when file system is mounted.
189 * Intended for user to read if she wants.
191 const char *dev_name
;
192 /* Private data for our user (ie. gadget). Managed by user. */
195 /* filled by __ffs_data_got_descs() */
197 * Real descriptors are 16 bytes after raw_descs (so you need
198 * to skip 16 bytes (ie. ffs->raw_descs + 16) to get to the
199 * first full speed descriptor). raw_descs_length and
200 * raw_fs_descs_length do not have those 16 bytes added.
202 const void *raw_descs
;
203 unsigned raw_descs_length
;
204 unsigned raw_fs_descs_length
;
205 unsigned fs_descs_count
;
206 unsigned hs_descs_count
;
208 unsigned short strings_count
;
209 unsigned short interfaces_count
;
210 unsigned short eps_count
;
211 unsigned short _pad1
;
213 /* filled by __ffs_data_got_strings() */
214 /* ids in stringtabs are set in functionfs_bind() */
215 const void *raw_strings
;
216 struct usb_gadget_strings
**stringtabs
;
219 * File system's super block, write once when file system is
222 struct super_block
*sb
;
224 /* File permissions, written once when fs is mounted */
225 struct ffs_file_perms
{
232 * The endpoint files, filled by ffs_epfiles_create(),
233 * destroyed by ffs_epfiles_destroy().
235 struct ffs_epfile
*epfiles
;
238 /* Reference counter handling */
239 static void ffs_data_get(struct ffs_data
*ffs
);
240 static void ffs_data_put(struct ffs_data
*ffs
);
241 /* Creates new ffs_data object. */
242 static struct ffs_data
*__must_check
ffs_data_new(void) __attribute__((malloc
));
244 /* Opened counter handling. */
245 static void ffs_data_opened(struct ffs_data
*ffs
);
246 static void ffs_data_closed(struct ffs_data
*ffs
);
248 /* Called with ffs->mutex held; take over ownership of data. */
249 static int __must_check
250 __ffs_data_got_descs(struct ffs_data
*ffs
, char *data
, size_t len
);
251 static int __must_check
252 __ffs_data_got_strings(struct ffs_data
*ffs
, char *data
, size_t len
);
255 /* The function structure ***************************************************/
259 struct ffs_function
{
260 struct usb_configuration
*conf
;
261 struct usb_gadget
*gadget
;
262 struct ffs_data
*ffs
;
266 short *interfaces_nums
;
268 struct usb_function function
;
272 static struct ffs_function
*ffs_func_from_usb(struct usb_function
*f
)
274 return container_of(f
, struct ffs_function
, function
);
277 static void ffs_func_free(struct ffs_function
*func
);
279 static void ffs_func_eps_disable(struct ffs_function
*func
);
280 static int __must_check
ffs_func_eps_enable(struct ffs_function
*func
);
282 static int ffs_func_bind(struct usb_configuration
*,
283 struct usb_function
*);
284 static void ffs_func_unbind(struct usb_configuration
*,
285 struct usb_function
*);
286 static int ffs_func_set_alt(struct usb_function
*, unsigned, unsigned);
287 static void ffs_func_disable(struct usb_function
*);
288 static int ffs_func_setup(struct usb_function
*,
289 const struct usb_ctrlrequest
*);
290 static void ffs_func_suspend(struct usb_function
*);
291 static void ffs_func_resume(struct usb_function
*);
294 static int ffs_func_revmap_ep(struct ffs_function
*func
, u8 num
);
295 static int ffs_func_revmap_intf(struct ffs_function
*func
, u8 intf
);
298 /* The endpoints structures *************************************************/
301 struct usb_ep
*ep
; /* P: ffs->eps_lock */
302 struct usb_request
*req
; /* P: epfile->mutex */
304 /* [0]: full speed, [1]: high speed */
305 struct usb_endpoint_descriptor
*descs
[2];
309 int status
; /* P: epfile->mutex */
313 /* Protects ep->ep and ep->req. */
315 wait_queue_head_t wait
;
317 struct ffs_data
*ffs
;
318 struct ffs_ep
*ep
; /* P: ffs->eps_lock */
320 struct dentry
*dentry
;
324 unsigned char in
; /* P: ffs->eps_lock */
325 unsigned char isoc
; /* P: ffs->eps_lock */
330 static int __must_check
ffs_epfiles_create(struct ffs_data
*ffs
);
331 static void ffs_epfiles_destroy(struct ffs_epfile
*epfiles
, unsigned count
);
333 static struct inode
*__must_check
334 ffs_sb_create_file(struct super_block
*sb
, const char *name
, void *data
,
335 const struct file_operations
*fops
,
336 struct dentry
**dentry_p
);
339 /* Misc helper functions ****************************************************/
341 static int ffs_mutex_lock(struct mutex
*mutex
, unsigned nonblock
)
342 __attribute__((warn_unused_result
, nonnull
));
343 static char *ffs_prepare_buffer(const char __user
*buf
, size_t len
)
344 __attribute__((warn_unused_result
, nonnull
));
347 /* Control file aka ep0 *****************************************************/
349 static void ffs_ep0_complete(struct usb_ep
*ep
, struct usb_request
*req
)
351 struct ffs_data
*ffs
= req
->context
;
353 complete_all(&ffs
->ep0req_completion
);
356 static int __ffs_ep0_queue_wait(struct ffs_data
*ffs
, char *data
, size_t len
)
358 struct usb_request
*req
= ffs
->ep0req
;
361 req
->zero
= len
< le16_to_cpu(ffs
->ev
.setup
.wLength
);
363 spin_unlock_irq(&ffs
->ev
.waitq
.lock
);
369 * UDC layer requires to provide a buffer even for ZLP, but should
370 * not use it at all. Let's provide some poisoned pointer to catch
371 * possible bug in the driver.
373 if (req
->buf
== NULL
)
374 req
->buf
= (void *)0xDEADBABE;
376 INIT_COMPLETION(ffs
->ep0req_completion
);
378 ret
= usb_ep_queue(ffs
->gadget
->ep0
, req
, GFP_ATOMIC
);
379 if (unlikely(ret
< 0))
382 ret
= wait_for_completion_interruptible(&ffs
->ep0req_completion
);
384 usb_ep_dequeue(ffs
->gadget
->ep0
, req
);
388 ffs
->setup_state
= FFS_NO_SETUP
;
389 return ffs
->ep0req_status
;
392 static int __ffs_ep0_stall(struct ffs_data
*ffs
)
394 if (ffs
->ev
.can_stall
) {
395 pr_vdebug("ep0 stall\n");
396 usb_ep_set_halt(ffs
->gadget
->ep0
);
397 ffs
->setup_state
= FFS_NO_SETUP
;
400 pr_debug("bogus ep0 stall!\n");
405 static ssize_t
ffs_ep0_write(struct file
*file
, const char __user
*buf
,
406 size_t len
, loff_t
*ptr
)
408 struct ffs_data
*ffs
= file
->private_data
;
414 /* Fast check if setup was canceled */
415 if (FFS_SETUP_STATE(ffs
) == FFS_SETUP_CANCELED
)
419 ret
= ffs_mutex_lock(&ffs
->mutex
, file
->f_flags
& O_NONBLOCK
);
420 if (unlikely(ret
< 0))
424 switch (ffs
->state
) {
425 case FFS_READ_DESCRIPTORS
:
426 case FFS_READ_STRINGS
:
428 if (unlikely(len
< 16)) {
433 data
= ffs_prepare_buffer(buf
, len
);
440 if (ffs
->state
== FFS_READ_DESCRIPTORS
) {
441 pr_info("read descriptors\n");
442 ret
= __ffs_data_got_descs(ffs
, data
, len
);
443 if (unlikely(ret
< 0))
446 ffs
->state
= FFS_READ_STRINGS
;
449 pr_info("read strings\n");
450 ret
= __ffs_data_got_strings(ffs
, data
, len
);
451 if (unlikely(ret
< 0))
454 ret
= ffs_epfiles_create(ffs
);
456 ffs
->state
= FFS_CLOSING
;
460 ffs
->state
= FFS_ACTIVE
;
461 mutex_unlock(&ffs
->mutex
);
463 ret
= functionfs_ready_callback(ffs
);
464 if (unlikely(ret
< 0)) {
465 ffs
->state
= FFS_CLOSING
;
469 set_bit(FFS_FL_CALL_CLOSED_CALLBACK
, &ffs
->flags
);
477 * We're called from user space, we can use _irq
478 * rather then _irqsave
480 spin_lock_irq(&ffs
->ev
.waitq
.lock
);
481 switch (FFS_SETUP_STATE(ffs
)) {
482 case FFS_SETUP_CANCELED
:
490 case FFS_SETUP_PENDING
:
494 /* FFS_SETUP_PENDING */
495 if (!(ffs
->ev
.setup
.bRequestType
& USB_DIR_IN
)) {
496 spin_unlock_irq(&ffs
->ev
.waitq
.lock
);
497 ret
= __ffs_ep0_stall(ffs
);
501 /* FFS_SETUP_PENDING and not stall */
502 len
= min(len
, (size_t)le16_to_cpu(ffs
->ev
.setup
.wLength
));
504 spin_unlock_irq(&ffs
->ev
.waitq
.lock
);
506 data
= ffs_prepare_buffer(buf
, len
);
512 spin_lock_irq(&ffs
->ev
.waitq
.lock
);
515 * We are guaranteed to be still in FFS_ACTIVE state
516 * but the state of setup could have changed from
517 * FFS_SETUP_PENDING to FFS_SETUP_CANCELED so we need
518 * to check for that. If that happened we copied data
519 * from user space in vain but it's unlikely.
521 * For sure we are not in FFS_NO_SETUP since this is
522 * the only place FFS_SETUP_PENDING -> FFS_NO_SETUP
523 * transition can be performed and it's protected by
526 if (FFS_SETUP_STATE(ffs
) == FFS_SETUP_CANCELED
) {
529 spin_unlock_irq(&ffs
->ev
.waitq
.lock
);
531 /* unlocks spinlock */
532 ret
= __ffs_ep0_queue_wait(ffs
, data
, len
);
542 mutex_unlock(&ffs
->mutex
);
546 static ssize_t
__ffs_ep0_read_events(struct ffs_data
*ffs
, char __user
*buf
,
550 * We are holding ffs->ev.waitq.lock and ffs->mutex and we need
553 struct usb_functionfs_event events
[n
];
556 memset(events
, 0, sizeof events
);
559 events
[i
].type
= ffs
->ev
.types
[i
];
560 if (events
[i
].type
== FUNCTIONFS_SETUP
) {
561 events
[i
].u
.setup
= ffs
->ev
.setup
;
562 ffs
->setup_state
= FFS_SETUP_PENDING
;
566 if (n
< ffs
->ev
.count
) {
568 memmove(ffs
->ev
.types
, ffs
->ev
.types
+ n
,
569 ffs
->ev
.count
* sizeof *ffs
->ev
.types
);
574 spin_unlock_irq(&ffs
->ev
.waitq
.lock
);
575 mutex_unlock(&ffs
->mutex
);
577 return unlikely(__copy_to_user(buf
, events
, sizeof events
))
578 ? -EFAULT
: sizeof events
;
581 static ssize_t
ffs_ep0_read(struct file
*file
, char __user
*buf
,
582 size_t len
, loff_t
*ptr
)
584 struct ffs_data
*ffs
= file
->private_data
;
591 /* Fast check if setup was canceled */
592 if (FFS_SETUP_STATE(ffs
) == FFS_SETUP_CANCELED
)
596 ret
= ffs_mutex_lock(&ffs
->mutex
, file
->f_flags
& O_NONBLOCK
);
597 if (unlikely(ret
< 0))
601 if (ffs
->state
!= FFS_ACTIVE
) {
607 * We're called from user space, we can use _irq rather then
610 spin_lock_irq(&ffs
->ev
.waitq
.lock
);
612 switch (FFS_SETUP_STATE(ffs
)) {
613 case FFS_SETUP_CANCELED
:
618 n
= len
/ sizeof(struct usb_functionfs_event
);
624 if ((file
->f_flags
& O_NONBLOCK
) && !ffs
->ev
.count
) {
629 if (wait_event_interruptible_exclusive_locked_irq(ffs
->ev
.waitq
,
635 return __ffs_ep0_read_events(ffs
, buf
,
636 min(n
, (size_t)ffs
->ev
.count
));
638 case FFS_SETUP_PENDING
:
639 if (ffs
->ev
.setup
.bRequestType
& USB_DIR_IN
) {
640 spin_unlock_irq(&ffs
->ev
.waitq
.lock
);
641 ret
= __ffs_ep0_stall(ffs
);
645 len
= min(len
, (size_t)le16_to_cpu(ffs
->ev
.setup
.wLength
));
647 spin_unlock_irq(&ffs
->ev
.waitq
.lock
);
650 data
= kmalloc(len
, GFP_KERNEL
);
651 if (unlikely(!data
)) {
657 spin_lock_irq(&ffs
->ev
.waitq
.lock
);
659 /* See ffs_ep0_write() */
660 if (FFS_SETUP_STATE(ffs
) == FFS_SETUP_CANCELED
) {
665 /* unlocks spinlock */
666 ret
= __ffs_ep0_queue_wait(ffs
, data
, len
);
667 if (likely(ret
> 0) && unlikely(__copy_to_user(buf
, data
, len
)))
676 spin_unlock_irq(&ffs
->ev
.waitq
.lock
);
678 mutex_unlock(&ffs
->mutex
);
683 static int ffs_ep0_open(struct inode
*inode
, struct file
*file
)
685 struct ffs_data
*ffs
= inode
->i_private
;
689 if (unlikely(ffs
->state
== FFS_CLOSING
))
692 file
->private_data
= ffs
;
693 ffs_data_opened(ffs
);
698 static int ffs_ep0_release(struct inode
*inode
, struct file
*file
)
700 struct ffs_data
*ffs
= file
->private_data
;
704 ffs_data_closed(ffs
);
709 static long ffs_ep0_ioctl(struct file
*file
, unsigned code
, unsigned long value
)
711 struct ffs_data
*ffs
= file
->private_data
;
712 struct usb_gadget
*gadget
= ffs
->gadget
;
717 if (code
== FUNCTIONFS_INTERFACE_REVMAP
) {
718 struct ffs_function
*func
= ffs
->func
;
719 ret
= func
? ffs_func_revmap_intf(func
, value
) : -ENODEV
;
720 } else if (gadget
&& gadget
->ops
->ioctl
) {
721 ret
= gadget
->ops
->ioctl(gadget
, code
, value
);
729 static const struct file_operations ffs_ep0_operations
= {
730 .owner
= THIS_MODULE
,
733 .open
= ffs_ep0_open
,
734 .write
= ffs_ep0_write
,
735 .read
= ffs_ep0_read
,
736 .release
= ffs_ep0_release
,
737 .unlocked_ioctl
= ffs_ep0_ioctl
,
741 /* "Normal" endpoints operations ********************************************/
743 static void ffs_epfile_io_complete(struct usb_ep
*_ep
, struct usb_request
*req
)
746 if (likely(req
->context
)) {
747 struct ffs_ep
*ep
= _ep
->driver_data
;
748 ep
->status
= req
->status
? req
->status
: req
->actual
;
749 complete(req
->context
);
753 static ssize_t
ffs_epfile_io(struct file
*file
,
754 char __user
*buf
, size_t len
, int read
)
756 struct ffs_epfile
*epfile
= file
->private_data
;
764 spin_unlock_irq(&epfile
->ffs
->eps_lock
);
765 mutex_unlock(&epfile
->mutex
);
768 /* Are we still active? */
769 if (WARN_ON(epfile
->ffs
->state
!= FFS_ACTIVE
)) {
774 /* Wait for endpoint to be enabled */
777 if (file
->f_flags
& O_NONBLOCK
) {
782 if (wait_event_interruptible(epfile
->wait
,
783 (ep
= epfile
->ep
))) {
790 halt
= !read
== !epfile
->in
;
791 if (halt
&& epfile
->isoc
) {
796 /* Allocate & copy */
797 if (!halt
&& !data
) {
798 data
= kzalloc(len
, GFP_KERNEL
);
803 unlikely(__copy_from_user(data
, buf
, len
))) {
809 /* We will be using request */
810 ret
= ffs_mutex_lock(&epfile
->mutex
,
811 file
->f_flags
& O_NONBLOCK
);
816 * We're called from user space, we can use _irq rather then
819 spin_lock_irq(&epfile
->ffs
->eps_lock
);
822 * While we were acquiring mutex endpoint got disabled
825 } while (unlikely(epfile
->ep
!= ep
));
828 if (unlikely(halt
)) {
829 if (likely(epfile
->ep
== ep
) && !WARN_ON(!ep
->ep
))
830 usb_ep_set_halt(ep
->ep
);
831 spin_unlock_irq(&epfile
->ffs
->eps_lock
);
834 /* Fire the request */
835 DECLARE_COMPLETION_ONSTACK(done
);
837 struct usb_request
*req
= ep
->req
;
838 req
->context
= &done
;
839 req
->complete
= ffs_epfile_io_complete
;
843 ret
= usb_ep_queue(ep
->ep
, req
, GFP_ATOMIC
);
845 spin_unlock_irq(&epfile
->ffs
->eps_lock
);
847 if (unlikely(ret
< 0)) {
849 } else if (unlikely(wait_for_completion_interruptible(&done
))) {
851 usb_ep_dequeue(ep
->ep
, req
);
854 if (read
&& ret
> 0 &&
855 unlikely(copy_to_user(buf
, data
, ret
)))
860 mutex_unlock(&epfile
->mutex
);
867 ffs_epfile_write(struct file
*file
, const char __user
*buf
, size_t len
,
872 return ffs_epfile_io(file
, (char __user
*)buf
, len
, 0);
876 ffs_epfile_read(struct file
*file
, char __user
*buf
, size_t len
, loff_t
*ptr
)
880 return ffs_epfile_io(file
, buf
, len
, 1);
884 ffs_epfile_open(struct inode
*inode
, struct file
*file
)
886 struct ffs_epfile
*epfile
= inode
->i_private
;
890 if (WARN_ON(epfile
->ffs
->state
!= FFS_ACTIVE
))
893 file
->private_data
= epfile
;
894 ffs_data_opened(epfile
->ffs
);
900 ffs_epfile_release(struct inode
*inode
, struct file
*file
)
902 struct ffs_epfile
*epfile
= inode
->i_private
;
906 ffs_data_closed(epfile
->ffs
);
911 static long ffs_epfile_ioctl(struct file
*file
, unsigned code
,
914 struct ffs_epfile
*epfile
= file
->private_data
;
919 if (WARN_ON(epfile
->ffs
->state
!= FFS_ACTIVE
))
922 spin_lock_irq(&epfile
->ffs
->eps_lock
);
923 if (likely(epfile
->ep
)) {
925 case FUNCTIONFS_FIFO_STATUS
:
926 ret
= usb_ep_fifo_status(epfile
->ep
->ep
);
928 case FUNCTIONFS_FIFO_FLUSH
:
929 usb_ep_fifo_flush(epfile
->ep
->ep
);
932 case FUNCTIONFS_CLEAR_HALT
:
933 ret
= usb_ep_clear_halt(epfile
->ep
->ep
);
935 case FUNCTIONFS_ENDPOINT_REVMAP
:
936 ret
= epfile
->ep
->num
;
944 spin_unlock_irq(&epfile
->ffs
->eps_lock
);
949 static const struct file_operations ffs_epfile_operations
= {
950 .owner
= THIS_MODULE
,
953 .open
= ffs_epfile_open
,
954 .write
= ffs_epfile_write
,
955 .read
= ffs_epfile_read
,
956 .release
= ffs_epfile_release
,
957 .unlocked_ioctl
= ffs_epfile_ioctl
,
961 /* File system and super block operations ***********************************/
964 * Mounting the file system creates a controller file, used first for
965 * function configuration then later for event monitoring.
968 static struct inode
*__must_check
969 ffs_sb_make_inode(struct super_block
*sb
, void *data
,
970 const struct file_operations
*fops
,
971 const struct inode_operations
*iops
,
972 struct ffs_file_perms
*perms
)
978 inode
= new_inode(sb
);
981 struct timespec current_time
= CURRENT_TIME
;
983 inode
->i_ino
= get_next_ino();
984 inode
->i_mode
= perms
->mode
;
985 inode
->i_uid
= perms
->uid
;
986 inode
->i_gid
= perms
->gid
;
987 inode
->i_atime
= current_time
;
988 inode
->i_mtime
= current_time
;
989 inode
->i_ctime
= current_time
;
990 inode
->i_private
= data
;
1000 /* Create "regular" file */
1001 static struct inode
*ffs_sb_create_file(struct super_block
*sb
,
1002 const char *name
, void *data
,
1003 const struct file_operations
*fops
,
1004 struct dentry
**dentry_p
)
1006 struct ffs_data
*ffs
= sb
->s_fs_info
;
1007 struct dentry
*dentry
;
1008 struct inode
*inode
;
1012 dentry
= d_alloc_name(sb
->s_root
, name
);
1013 if (unlikely(!dentry
))
1016 inode
= ffs_sb_make_inode(sb
, data
, fops
, NULL
, &ffs
->file_perms
);
1017 if (unlikely(!inode
)) {
1022 d_add(dentry
, inode
);
1030 static const struct super_operations ffs_sb_operations
= {
1031 .statfs
= simple_statfs
,
1032 .drop_inode
= generic_delete_inode
,
1035 struct ffs_sb_fill_data
{
1036 struct ffs_file_perms perms
;
1038 const char *dev_name
;
1040 /* set by ffs_fs_mount(), read by ffs_sb_fill() */
1042 /* set by ffs_sb_fill(), read by ffs_fs_mount */
1043 struct ffs_data
*ffs_data
;
1047 static int ffs_sb_fill(struct super_block
*sb
, void *_data
, int silent
)
1049 struct ffs_sb_fill_data
*data
= _data
;
1050 struct inode
*inode
;
1051 struct ffs_data
*ffs
;
1055 /* Initialise data */
1056 ffs
= ffs_data_new();
1061 ffs
->dev_name
= kstrdup(data
->dev_name
, GFP_KERNEL
);
1062 if (unlikely(!ffs
->dev_name
))
1064 ffs
->file_perms
= data
->perms
;
1065 ffs
->private_data
= data
->private_data
;
1067 /* used by the caller of this function */
1068 data
->ffs_data
= ffs
;
1070 sb
->s_fs_info
= ffs
;
1071 sb
->s_blocksize
= PAGE_CACHE_SIZE
;
1072 sb
->s_blocksize_bits
= PAGE_CACHE_SHIFT
;
1073 sb
->s_magic
= FUNCTIONFS_MAGIC
;
1074 sb
->s_op
= &ffs_sb_operations
;
1075 sb
->s_time_gran
= 1;
1078 data
->perms
.mode
= data
->root_mode
;
1079 inode
= ffs_sb_make_inode(sb
, NULL
,
1080 &simple_dir_operations
,
1081 &simple_dir_inode_operations
,
1083 sb
->s_root
= d_make_root(inode
);
1084 if (unlikely(!sb
->s_root
))
1088 if (unlikely(!ffs_sb_create_file(sb
, "ep0", ffs
,
1089 &ffs_ep0_operations
, NULL
)))
1098 static int ffs_fs_parse_opts(struct ffs_sb_fill_data
*data
, char *opts
)
1102 if (!opts
|| !*opts
)
1106 unsigned long value
;
1110 comma
= strchr(opts
, ',');
1115 eq
= strchr(opts
, '=');
1116 if (unlikely(!eq
)) {
1117 pr_err("'=' missing in %s\n", opts
);
1123 if (kstrtoul(eq
+ 1, 0, &value
)) {
1124 pr_err("%s: invalid value: %s\n", opts
, eq
+ 1);
1128 /* Interpret option */
1129 switch (eq
- opts
) {
1131 if (!memcmp(opts
, "rmode", 5))
1132 data
->root_mode
= (value
& 0555) | S_IFDIR
;
1133 else if (!memcmp(opts
, "fmode", 5))
1134 data
->perms
.mode
= (value
& 0666) | S_IFREG
;
1140 if (!memcmp(opts
, "mode", 4)) {
1141 data
->root_mode
= (value
& 0555) | S_IFDIR
;
1142 data
->perms
.mode
= (value
& 0666) | S_IFREG
;
1149 if (!memcmp(opts
, "uid", 3)) {
1150 data
->perms
.uid
= make_kuid(current_user_ns(), value
);
1151 if (!uid_valid(data
->perms
.uid
)) {
1152 pr_err("%s: unmapped value: %lu\n", opts
, value
);
1155 } else if (!memcmp(opts
, "gid", 3)) {
1156 data
->perms
.gid
= make_kgid(current_user_ns(), value
);
1157 if (!gid_valid(data
->perms
.gid
)) {
1158 pr_err("%s: unmapped value: %lu\n", opts
, value
);
1168 pr_err("%s: invalid option\n", opts
);
1172 /* Next iteration */
1181 /* "mount -t functionfs dev_name /dev/function" ends up here */
1183 static struct dentry
*
1184 ffs_fs_mount(struct file_system_type
*t
, int flags
,
1185 const char *dev_name
, void *opts
)
1187 struct ffs_sb_fill_data data
= {
1189 .mode
= S_IFREG
| 0600,
1190 .uid
= GLOBAL_ROOT_UID
,
1191 .gid
= GLOBAL_ROOT_GID
,
1193 .root_mode
= S_IFDIR
| 0500,
1201 ret
= ffs_fs_parse_opts(&data
, opts
);
1202 if (unlikely(ret
< 0))
1203 return ERR_PTR(ret
);
1205 ffs_dev
= functionfs_acquire_dev_callback(dev_name
);
1206 if (IS_ERR(ffs_dev
))
1209 data
.dev_name
= dev_name
;
1210 data
.private_data
= ffs_dev
;
1211 rv
= mount_nodev(t
, flags
, &data
, ffs_sb_fill
);
1213 /* data.ffs_data is set by ffs_sb_fill */
1215 functionfs_release_dev_callback(data
.ffs_data
);
1221 ffs_fs_kill_sb(struct super_block
*sb
)
1225 kill_litter_super(sb
);
1226 if (sb
->s_fs_info
) {
1227 functionfs_release_dev_callback(sb
->s_fs_info
);
1228 ffs_data_put(sb
->s_fs_info
);
1232 static struct file_system_type ffs_fs_type
= {
1233 .owner
= THIS_MODULE
,
1234 .name
= "functionfs",
1235 .mount
= ffs_fs_mount
,
1236 .kill_sb
= ffs_fs_kill_sb
,
1240 /* Driver's main init/cleanup functions *************************************/
1242 static int functionfs_init(void)
1248 ret
= register_filesystem(&ffs_fs_type
);
1250 pr_info("file system registered\n");
1252 pr_err("failed registering file system (%d)\n", ret
);
1257 static void functionfs_cleanup(void)
1261 pr_info("unloading\n");
1262 unregister_filesystem(&ffs_fs_type
);
1266 /* ffs_data and ffs_function construction and destruction code **************/
1268 static void ffs_data_clear(struct ffs_data
*ffs
);
1269 static void ffs_data_reset(struct ffs_data
*ffs
);
1271 static void ffs_data_get(struct ffs_data
*ffs
)
1275 atomic_inc(&ffs
->ref
);
1278 static void ffs_data_opened(struct ffs_data
*ffs
)
1282 atomic_inc(&ffs
->ref
);
1283 atomic_inc(&ffs
->opened
);
1286 static void ffs_data_put(struct ffs_data
*ffs
)
1290 if (unlikely(atomic_dec_and_test(&ffs
->ref
))) {
1291 pr_info("%s(): freeing\n", __func__
);
1292 ffs_data_clear(ffs
);
1293 BUG_ON(waitqueue_active(&ffs
->ev
.waitq
) ||
1294 waitqueue_active(&ffs
->ep0req_completion
.wait
));
1295 kfree(ffs
->dev_name
);
1300 static void ffs_data_closed(struct ffs_data
*ffs
)
1304 if (atomic_dec_and_test(&ffs
->opened
)) {
1305 ffs
->state
= FFS_CLOSING
;
1306 ffs_data_reset(ffs
);
1312 static struct ffs_data
*ffs_data_new(void)
1314 struct ffs_data
*ffs
= kzalloc(sizeof *ffs
, GFP_KERNEL
);
1320 atomic_set(&ffs
->ref
, 1);
1321 atomic_set(&ffs
->opened
, 0);
1322 ffs
->state
= FFS_READ_DESCRIPTORS
;
1323 mutex_init(&ffs
->mutex
);
1324 spin_lock_init(&ffs
->eps_lock
);
1325 init_waitqueue_head(&ffs
->ev
.waitq
);
1326 init_completion(&ffs
->ep0req_completion
);
1328 /* XXX REVISIT need to update it in some places, or do we? */
1329 ffs
->ev
.can_stall
= 1;
1334 static void ffs_data_clear(struct ffs_data
*ffs
)
1338 if (test_and_clear_bit(FFS_FL_CALL_CLOSED_CALLBACK
, &ffs
->flags
))
1339 functionfs_closed_callback(ffs
);
1341 BUG_ON(ffs
->gadget
);
1344 ffs_epfiles_destroy(ffs
->epfiles
, ffs
->eps_count
);
1346 kfree(ffs
->raw_descs
);
1347 kfree(ffs
->raw_strings
);
1348 kfree(ffs
->stringtabs
);
1351 static void ffs_data_reset(struct ffs_data
*ffs
)
1355 ffs_data_clear(ffs
);
1357 ffs
->epfiles
= NULL
;
1358 ffs
->raw_descs
= NULL
;
1359 ffs
->raw_strings
= NULL
;
1360 ffs
->stringtabs
= NULL
;
1362 ffs
->raw_descs_length
= 0;
1363 ffs
->raw_fs_descs_length
= 0;
1364 ffs
->fs_descs_count
= 0;
1365 ffs
->hs_descs_count
= 0;
1367 ffs
->strings_count
= 0;
1368 ffs
->interfaces_count
= 0;
1373 ffs
->state
= FFS_READ_DESCRIPTORS
;
1374 ffs
->setup_state
= FFS_NO_SETUP
;
1379 static int functionfs_bind(struct ffs_data
*ffs
, struct usb_composite_dev
*cdev
)
1381 struct usb_gadget_strings
**lang
;
1386 if (WARN_ON(ffs
->state
!= FFS_ACTIVE
1387 || test_and_set_bit(FFS_FL_BOUND
, &ffs
->flags
)))
1390 first_id
= usb_string_ids_n(cdev
, ffs
->strings_count
);
1391 if (unlikely(first_id
< 0))
1394 ffs
->ep0req
= usb_ep_alloc_request(cdev
->gadget
->ep0
, GFP_KERNEL
);
1395 if (unlikely(!ffs
->ep0req
))
1397 ffs
->ep0req
->complete
= ffs_ep0_complete
;
1398 ffs
->ep0req
->context
= ffs
;
1400 lang
= ffs
->stringtabs
;
1401 for (lang
= ffs
->stringtabs
; *lang
; ++lang
) {
1402 struct usb_string
*str
= (*lang
)->strings
;
1404 for (; str
->s
; ++id
, ++str
)
1408 ffs
->gadget
= cdev
->gadget
;
1413 static void functionfs_unbind(struct ffs_data
*ffs
)
1417 if (!WARN_ON(!ffs
->gadget
)) {
1418 usb_ep_free_request(ffs
->gadget
->ep0
, ffs
->ep0req
);
1422 clear_bit(FFS_FL_BOUND
, &ffs
->flags
);
1426 static int ffs_epfiles_create(struct ffs_data
*ffs
)
1428 struct ffs_epfile
*epfile
, *epfiles
;
1433 count
= ffs
->eps_count
;
1434 epfiles
= kcalloc(count
, sizeof(*epfiles
), GFP_KERNEL
);
1439 for (i
= 1; i
<= count
; ++i
, ++epfile
) {
1441 mutex_init(&epfile
->mutex
);
1442 init_waitqueue_head(&epfile
->wait
);
1443 sprintf(epfiles
->name
, "ep%u", i
);
1444 if (!unlikely(ffs_sb_create_file(ffs
->sb
, epfiles
->name
, epfile
,
1445 &ffs_epfile_operations
,
1446 &epfile
->dentry
))) {
1447 ffs_epfiles_destroy(epfiles
, i
- 1);
1452 ffs
->epfiles
= epfiles
;
1456 static void ffs_epfiles_destroy(struct ffs_epfile
*epfiles
, unsigned count
)
1458 struct ffs_epfile
*epfile
= epfiles
;
1462 for (; count
; --count
, ++epfile
) {
1463 BUG_ON(mutex_is_locked(&epfile
->mutex
) ||
1464 waitqueue_active(&epfile
->wait
));
1465 if (epfile
->dentry
) {
1466 d_delete(epfile
->dentry
);
1467 dput(epfile
->dentry
);
1468 epfile
->dentry
= NULL
;
1475 static int functionfs_bind_config(struct usb_composite_dev
*cdev
,
1476 struct usb_configuration
*c
,
1477 struct ffs_data
*ffs
)
1479 struct ffs_function
*func
;
1484 func
= kzalloc(sizeof *func
, GFP_KERNEL
);
1485 if (unlikely(!func
))
1488 func
->function
.name
= "Function FS Gadget";
1489 func
->function
.strings
= ffs
->stringtabs
;
1491 func
->function
.bind
= ffs_func_bind
;
1492 func
->function
.unbind
= ffs_func_unbind
;
1493 func
->function
.set_alt
= ffs_func_set_alt
;
1494 func
->function
.disable
= ffs_func_disable
;
1495 func
->function
.setup
= ffs_func_setup
;
1496 func
->function
.suspend
= ffs_func_suspend
;
1497 func
->function
.resume
= ffs_func_resume
;
1500 func
->gadget
= cdev
->gadget
;
1504 ret
= usb_add_function(c
, &func
->function
);
1506 ffs_func_free(func
);
1511 static void ffs_func_free(struct ffs_function
*func
)
1513 struct ffs_ep
*ep
= func
->eps
;
1514 unsigned count
= func
->ffs
->eps_count
;
1515 unsigned long flags
;
1519 /* cleanup after autoconfig */
1520 spin_lock_irqsave(&func
->ffs
->eps_lock
, flags
);
1522 if (ep
->ep
&& ep
->req
)
1523 usb_ep_free_request(ep
->ep
, ep
->req
);
1527 spin_unlock_irqrestore(&func
->ffs
->eps_lock
, flags
);
1529 ffs_data_put(func
->ffs
);
1533 * eps and interfaces_nums are allocated in the same chunk so
1534 * only one free is required. Descriptors are also allocated
1535 * in the same chunk.
1541 static void ffs_func_eps_disable(struct ffs_function
*func
)
1543 struct ffs_ep
*ep
= func
->eps
;
1544 struct ffs_epfile
*epfile
= func
->ffs
->epfiles
;
1545 unsigned count
= func
->ffs
->eps_count
;
1546 unsigned long flags
;
1548 spin_lock_irqsave(&func
->ffs
->eps_lock
, flags
);
1550 /* pending requests get nuked */
1552 usb_ep_disable(ep
->ep
);
1558 spin_unlock_irqrestore(&func
->ffs
->eps_lock
, flags
);
1561 static int ffs_func_eps_enable(struct ffs_function
*func
)
1563 struct ffs_data
*ffs
= func
->ffs
;
1564 struct ffs_ep
*ep
= func
->eps
;
1565 struct ffs_epfile
*epfile
= ffs
->epfiles
;
1566 unsigned count
= ffs
->eps_count
;
1567 unsigned long flags
;
1570 spin_lock_irqsave(&func
->ffs
->eps_lock
, flags
);
1572 struct usb_endpoint_descriptor
*ds
;
1573 ds
= ep
->descs
[ep
->descs
[1] ? 1 : 0];
1575 ep
->ep
->driver_data
= ep
;
1577 ret
= usb_ep_enable(ep
->ep
);
1580 epfile
->in
= usb_endpoint_dir_in(ds
);
1581 epfile
->isoc
= usb_endpoint_xfer_isoc(ds
);
1586 wake_up(&epfile
->wait
);
1591 spin_unlock_irqrestore(&func
->ffs
->eps_lock
, flags
);
1597 /* Parsing and building descriptors and strings *****************************/
1600 * This validates if data pointed by data is a valid USB descriptor as
1601 * well as record how many interfaces, endpoints and strings are
1602 * required by given configuration. Returns address after the
1603 * descriptor or NULL if data is invalid.
1606 enum ffs_entity_type
{
1607 FFS_DESCRIPTOR
, FFS_INTERFACE
, FFS_STRING
, FFS_ENDPOINT
1610 typedef int (*ffs_entity_callback
)(enum ffs_entity_type entity
,
1612 struct usb_descriptor_header
*desc
,
1615 static int __must_check
ffs_do_desc(char *data
, unsigned len
,
1616 ffs_entity_callback entity
, void *priv
)
1618 struct usb_descriptor_header
*_ds
= (void *)data
;
1624 /* At least two bytes are required: length and type */
1626 pr_vdebug("descriptor too short\n");
1630 /* If we have at least as many bytes as the descriptor takes? */
1631 length
= _ds
->bLength
;
1633 pr_vdebug("descriptor longer then available data\n");
1637 #define __entity_check_INTERFACE(val) 1
1638 #define __entity_check_STRING(val) (val)
1639 #define __entity_check_ENDPOINT(val) ((val) & USB_ENDPOINT_NUMBER_MASK)
1640 #define __entity(type, val) do { \
1641 pr_vdebug("entity " #type "(%02x)\n", (val)); \
1642 if (unlikely(!__entity_check_ ##type(val))) { \
1643 pr_vdebug("invalid entity's value\n"); \
1646 ret = entity(FFS_ ##type, &val, _ds, priv); \
1647 if (unlikely(ret < 0)) { \
1648 pr_debug("entity " #type "(%02x); ret = %d\n", \
1654 /* Parse descriptor depending on type. */
1655 switch (_ds
->bDescriptorType
) {
1659 case USB_DT_DEVICE_QUALIFIER
:
1660 /* function can't have any of those */
1661 pr_vdebug("descriptor reserved for gadget: %d\n",
1662 _ds
->bDescriptorType
);
1665 case USB_DT_INTERFACE
: {
1666 struct usb_interface_descriptor
*ds
= (void *)_ds
;
1667 pr_vdebug("interface descriptor\n");
1668 if (length
!= sizeof *ds
)
1671 __entity(INTERFACE
, ds
->bInterfaceNumber
);
1673 __entity(STRING
, ds
->iInterface
);
1677 case USB_DT_ENDPOINT
: {
1678 struct usb_endpoint_descriptor
*ds
= (void *)_ds
;
1679 pr_vdebug("endpoint descriptor\n");
1680 if (length
!= USB_DT_ENDPOINT_SIZE
&&
1681 length
!= USB_DT_ENDPOINT_AUDIO_SIZE
)
1683 __entity(ENDPOINT
, ds
->bEndpointAddress
);
1688 pr_vdebug("hid descriptor\n");
1689 if (length
!= sizeof(struct hid_descriptor
))
1694 if (length
!= sizeof(struct usb_otg_descriptor
))
1698 case USB_DT_INTERFACE_ASSOCIATION
: {
1699 struct usb_interface_assoc_descriptor
*ds
= (void *)_ds
;
1700 pr_vdebug("interface association descriptor\n");
1701 if (length
!= sizeof *ds
)
1704 __entity(STRING
, ds
->iFunction
);
1708 case USB_DT_OTHER_SPEED_CONFIG
:
1709 case USB_DT_INTERFACE_POWER
:
1711 case USB_DT_SECURITY
:
1712 case USB_DT_CS_RADIO_CONTROL
:
1714 pr_vdebug("unimplemented descriptor: %d\n", _ds
->bDescriptorType
);
1718 /* We should never be here */
1719 pr_vdebug("unknown descriptor: %d\n", _ds
->bDescriptorType
);
1723 pr_vdebug("invalid length: %d (descriptor %d)\n",
1724 _ds
->bLength
, _ds
->bDescriptorType
);
1729 #undef __entity_check_DESCRIPTOR
1730 #undef __entity_check_INTERFACE
1731 #undef __entity_check_STRING
1732 #undef __entity_check_ENDPOINT
1737 static int __must_check
ffs_do_descs(unsigned count
, char *data
, unsigned len
,
1738 ffs_entity_callback entity
, void *priv
)
1740 const unsigned _len
= len
;
1741 unsigned long num
= 0;
1751 /* Record "descriptor" entity */
1752 ret
= entity(FFS_DESCRIPTOR
, (u8
*)num
, (void *)data
, priv
);
1753 if (unlikely(ret
< 0)) {
1754 pr_debug("entity DESCRIPTOR(%02lx); ret = %d\n",
1762 ret
= ffs_do_desc(data
, len
, entity
, priv
);
1763 if (unlikely(ret
< 0)) {
1764 pr_debug("%s returns %d\n", __func__
, ret
);
1774 static int __ffs_data_do_entity(enum ffs_entity_type type
,
1775 u8
*valuep
, struct usb_descriptor_header
*desc
,
1778 struct ffs_data
*ffs
= priv
;
1783 case FFS_DESCRIPTOR
:
1788 * Interfaces are indexed from zero so if we
1789 * encountered interface "n" then there are at least
1792 if (*valuep
>= ffs
->interfaces_count
)
1793 ffs
->interfaces_count
= *valuep
+ 1;
1798 * Strings are indexed from 1 (0 is magic ;) reserved
1799 * for languages list or some such)
1801 if (*valuep
> ffs
->strings_count
)
1802 ffs
->strings_count
= *valuep
;
1806 /* Endpoints are indexed from 1 as well. */
1807 if ((*valuep
& USB_ENDPOINT_NUMBER_MASK
) > ffs
->eps_count
)
1808 ffs
->eps_count
= (*valuep
& USB_ENDPOINT_NUMBER_MASK
);
1815 static int __ffs_data_got_descs(struct ffs_data
*ffs
,
1816 char *const _data
, size_t len
)
1818 unsigned fs_count
, hs_count
;
1819 int fs_len
, ret
= -EINVAL
;
1824 if (unlikely(get_unaligned_le32(data
) != FUNCTIONFS_DESCRIPTORS_MAGIC
||
1825 get_unaligned_le32(data
+ 4) != len
))
1827 fs_count
= get_unaligned_le32(data
+ 8);
1828 hs_count
= get_unaligned_le32(data
+ 12);
1830 if (!fs_count
&& !hs_count
)
1836 if (likely(fs_count
)) {
1837 fs_len
= ffs_do_descs(fs_count
, data
, len
,
1838 __ffs_data_do_entity
, ffs
);
1839 if (unlikely(fs_len
< 0)) {
1850 if (likely(hs_count
)) {
1851 ret
= ffs_do_descs(hs_count
, data
, len
,
1852 __ffs_data_do_entity
, ffs
);
1853 if (unlikely(ret
< 0))
1859 if (unlikely(len
!= ret
))
1862 ffs
->raw_fs_descs_length
= fs_len
;
1863 ffs
->raw_descs_length
= fs_len
+ ret
;
1864 ffs
->raw_descs
= _data
;
1865 ffs
->fs_descs_count
= fs_count
;
1866 ffs
->hs_descs_count
= hs_count
;
1877 static int __ffs_data_got_strings(struct ffs_data
*ffs
,
1878 char *const _data
, size_t len
)
1880 u32 str_count
, needed_count
, lang_count
;
1881 struct usb_gadget_strings
**stringtabs
, *t
;
1882 struct usb_string
*strings
, *s
;
1883 const char *data
= _data
;
1887 if (unlikely(get_unaligned_le32(data
) != FUNCTIONFS_STRINGS_MAGIC
||
1888 get_unaligned_le32(data
+ 4) != len
))
1890 str_count
= get_unaligned_le32(data
+ 8);
1891 lang_count
= get_unaligned_le32(data
+ 12);
1893 /* if one is zero the other must be zero */
1894 if (unlikely(!str_count
!= !lang_count
))
1897 /* Do we have at least as many strings as descriptors need? */
1898 needed_count
= ffs
->strings_count
;
1899 if (unlikely(str_count
< needed_count
))
1903 * If we don't need any strings just return and free all
1906 if (!needed_count
) {
1911 /* Allocate everything in one chunk so there's less maintenance. */
1914 struct usb_gadget_strings
*stringtabs
[lang_count
+ 1];
1915 struct usb_gadget_strings stringtab
[lang_count
];
1916 struct usb_string strings
[lang_count
*(needed_count
+1)];
1920 d
= kmalloc(sizeof *d
, GFP_KERNEL
);
1926 stringtabs
= d
->stringtabs
;
1930 *stringtabs
++ = t
++;
1934 stringtabs
= d
->stringtabs
;
1940 /* For each language */
1944 do { /* lang_count > 0 so we can use do-while */
1945 unsigned needed
= needed_count
;
1947 if (unlikely(len
< 3))
1949 t
->language
= get_unaligned_le16(data
);
1956 /* For each string */
1957 do { /* str_count > 0 so we can use do-while */
1958 size_t length
= strnlen(data
, len
);
1960 if (unlikely(length
== len
))
1964 * User may provide more strings then we need,
1965 * if that's the case we simply ignore the
1968 if (likely(needed
)) {
1970 * s->id will be set while adding
1971 * function to configuration so for
1972 * now just leave garbage here.
1981 } while (--str_count
);
1983 s
->id
= 0; /* terminator */
1987 } while (--lang_count
);
1989 /* Some garbage left? */
1994 ffs
->stringtabs
= stringtabs
;
1995 ffs
->raw_strings
= _data
;
2007 /* Events handling and management *******************************************/
2009 static void __ffs_event_add(struct ffs_data
*ffs
,
2010 enum usb_functionfs_event_type type
)
2012 enum usb_functionfs_event_type rem_type1
, rem_type2
= type
;
2016 * Abort any unhandled setup
2018 * We do not need to worry about some cmpxchg() changing value
2019 * of ffs->setup_state without holding the lock because when
2020 * state is FFS_SETUP_PENDING cmpxchg() in several places in
2021 * the source does nothing.
2023 if (ffs
->setup_state
== FFS_SETUP_PENDING
)
2024 ffs
->setup_state
= FFS_SETUP_CANCELED
;
2027 case FUNCTIONFS_RESUME
:
2028 rem_type2
= FUNCTIONFS_SUSPEND
;
2030 case FUNCTIONFS_SUSPEND
:
2031 case FUNCTIONFS_SETUP
:
2033 /* Discard all similar events */
2036 case FUNCTIONFS_BIND
:
2037 case FUNCTIONFS_UNBIND
:
2038 case FUNCTIONFS_DISABLE
:
2039 case FUNCTIONFS_ENABLE
:
2040 /* Discard everything other then power management. */
2041 rem_type1
= FUNCTIONFS_SUSPEND
;
2042 rem_type2
= FUNCTIONFS_RESUME
;
2051 u8
*ev
= ffs
->ev
.types
, *out
= ev
;
2052 unsigned n
= ffs
->ev
.count
;
2053 for (; n
; --n
, ++ev
)
2054 if ((*ev
== rem_type1
|| *ev
== rem_type2
) == neg
)
2057 pr_vdebug("purging event %d\n", *ev
);
2058 ffs
->ev
.count
= out
- ffs
->ev
.types
;
2061 pr_vdebug("adding event %d\n", type
);
2062 ffs
->ev
.types
[ffs
->ev
.count
++] = type
;
2063 wake_up_locked(&ffs
->ev
.waitq
);
2066 static void ffs_event_add(struct ffs_data
*ffs
,
2067 enum usb_functionfs_event_type type
)
2069 unsigned long flags
;
2070 spin_lock_irqsave(&ffs
->ev
.waitq
.lock
, flags
);
2071 __ffs_event_add(ffs
, type
);
2072 spin_unlock_irqrestore(&ffs
->ev
.waitq
.lock
, flags
);
2076 /* Bind/unbind USB function hooks *******************************************/
2078 static int __ffs_func_bind_do_descs(enum ffs_entity_type type
, u8
*valuep
,
2079 struct usb_descriptor_header
*desc
,
2082 struct usb_endpoint_descriptor
*ds
= (void *)desc
;
2083 struct ffs_function
*func
= priv
;
2084 struct ffs_ep
*ffs_ep
;
2087 * If hs_descriptors is not NULL then we are reading hs
2090 const int isHS
= func
->function
.hs_descriptors
!= NULL
;
2093 if (type
!= FFS_DESCRIPTOR
)
2097 func
->function
.hs_descriptors
[(long)valuep
] = desc
;
2099 func
->function
.fs_descriptors
[(long)valuep
] = desc
;
2101 if (!desc
|| desc
->bDescriptorType
!= USB_DT_ENDPOINT
)
2104 idx
= (ds
->bEndpointAddress
& USB_ENDPOINT_NUMBER_MASK
) - 1;
2105 ffs_ep
= func
->eps
+ idx
;
2107 if (unlikely(ffs_ep
->descs
[isHS
])) {
2108 pr_vdebug("two %sspeed descriptors for EP %d\n",
2109 isHS
? "high" : "full",
2110 ds
->bEndpointAddress
& USB_ENDPOINT_NUMBER_MASK
);
2113 ffs_ep
->descs
[isHS
] = ds
;
2115 ffs_dump_mem(": Original ep desc", ds
, ds
->bLength
);
2117 ds
->bEndpointAddress
= ffs_ep
->descs
[0]->bEndpointAddress
;
2118 if (!ds
->wMaxPacketSize
)
2119 ds
->wMaxPacketSize
= ffs_ep
->descs
[0]->wMaxPacketSize
;
2121 struct usb_request
*req
;
2124 pr_vdebug("autoconfig\n");
2125 ep
= usb_ep_autoconfig(func
->gadget
, ds
);
2128 ep
->driver_data
= func
->eps
+ idx
;
2130 req
= usb_ep_alloc_request(ep
, GFP_KERNEL
);
2136 func
->eps_revmap
[ds
->bEndpointAddress
&
2137 USB_ENDPOINT_NUMBER_MASK
] = idx
+ 1;
2139 ffs_dump_mem(": Rewritten ep desc", ds
, ds
->bLength
);
2144 static int __ffs_func_bind_do_nums(enum ffs_entity_type type
, u8
*valuep
,
2145 struct usb_descriptor_header
*desc
,
2148 struct ffs_function
*func
= priv
;
2154 case FFS_DESCRIPTOR
:
2155 /* Handled in previous pass by __ffs_func_bind_do_descs() */
2160 if (func
->interfaces_nums
[idx
] < 0) {
2161 int id
= usb_interface_id(func
->conf
, &func
->function
);
2162 if (unlikely(id
< 0))
2164 func
->interfaces_nums
[idx
] = id
;
2166 newValue
= func
->interfaces_nums
[idx
];
2170 /* String' IDs are allocated when fsf_data is bound to cdev */
2171 newValue
= func
->ffs
->stringtabs
[0]->strings
[*valuep
- 1].id
;
2176 * USB_DT_ENDPOINT are handled in
2177 * __ffs_func_bind_do_descs().
2179 if (desc
->bDescriptorType
== USB_DT_ENDPOINT
)
2182 idx
= (*valuep
& USB_ENDPOINT_NUMBER_MASK
) - 1;
2183 if (unlikely(!func
->eps
[idx
].ep
))
2187 struct usb_endpoint_descriptor
**descs
;
2188 descs
= func
->eps
[idx
].descs
;
2189 newValue
= descs
[descs
[0] ? 0 : 1]->bEndpointAddress
;
2194 pr_vdebug("%02x -> %02x\n", *valuep
, newValue
);
2199 static int ffs_func_bind(struct usb_configuration
*c
,
2200 struct usb_function
*f
)
2202 struct ffs_function
*func
= ffs_func_from_usb(f
);
2203 struct ffs_data
*ffs
= func
->ffs
;
2205 const int full
= !!func
->ffs
->fs_descs_count
;
2206 const int high
= gadget_is_dualspeed(func
->gadget
) &&
2207 func
->ffs
->hs_descs_count
;
2211 /* Make it a single chunk, less management later on */
2213 struct ffs_ep eps
[ffs
->eps_count
];
2214 struct usb_descriptor_header
2215 *fs_descs
[full
? ffs
->fs_descs_count
+ 1 : 0];
2216 struct usb_descriptor_header
2217 *hs_descs
[high
? ffs
->hs_descs_count
+ 1 : 0];
2218 short inums
[ffs
->interfaces_count
];
2219 char raw_descs
[high
? ffs
->raw_descs_length
2220 : ffs
->raw_fs_descs_length
];
2225 /* Only high speed but not supported by gadget? */
2226 if (unlikely(!(full
| high
)))
2230 data
= kmalloc(sizeof *data
, GFP_KERNEL
);
2231 if (unlikely(!data
))
2235 memset(data
->eps
, 0, sizeof data
->eps
);
2236 memcpy(data
->raw_descs
, ffs
->raw_descs
+ 16, sizeof data
->raw_descs
);
2237 memset(data
->inums
, 0xff, sizeof data
->inums
);
2238 for (ret
= ffs
->eps_count
; ret
; --ret
)
2239 data
->eps
[ret
].num
= -1;
2242 func
->eps
= data
->eps
;
2243 func
->interfaces_nums
= data
->inums
;
2246 * Go through all the endpoint descriptors and allocate
2247 * endpoints first, so that later we can rewrite the endpoint
2248 * numbers without worrying that it may be described later on.
2251 func
->function
.fs_descriptors
= data
->fs_descs
;
2252 ret
= ffs_do_descs(ffs
->fs_descs_count
,
2254 sizeof data
->raw_descs
,
2255 __ffs_func_bind_do_descs
, func
);
2256 if (unlikely(ret
< 0))
2263 func
->function
.hs_descriptors
= data
->hs_descs
;
2264 ret
= ffs_do_descs(ffs
->hs_descs_count
,
2265 data
->raw_descs
+ ret
,
2266 (sizeof data
->raw_descs
) - ret
,
2267 __ffs_func_bind_do_descs
, func
);
2271 * Now handle interface numbers allocation and interface and
2272 * endpoint numbers rewriting. We can do that in one go
2275 ret
= ffs_do_descs(ffs
->fs_descs_count
+
2276 (high
? ffs
->hs_descs_count
: 0),
2277 data
->raw_descs
, sizeof data
->raw_descs
,
2278 __ffs_func_bind_do_nums
, func
);
2279 if (unlikely(ret
< 0))
2282 /* And we're done */
2283 ffs_event_add(ffs
, FUNCTIONFS_BIND
);
2287 /* XXX Do we need to release all claimed endpoints here? */
2292 /* Other USB function hooks *************************************************/
2294 static void ffs_func_unbind(struct usb_configuration
*c
,
2295 struct usb_function
*f
)
2297 struct ffs_function
*func
= ffs_func_from_usb(f
);
2298 struct ffs_data
*ffs
= func
->ffs
;
2302 if (ffs
->func
== func
) {
2303 ffs_func_eps_disable(func
);
2307 ffs_event_add(ffs
, FUNCTIONFS_UNBIND
);
2309 ffs_func_free(func
);
2312 static int ffs_func_set_alt(struct usb_function
*f
,
2313 unsigned interface
, unsigned alt
)
2315 struct ffs_function
*func
= ffs_func_from_usb(f
);
2316 struct ffs_data
*ffs
= func
->ffs
;
2319 if (alt
!= (unsigned)-1) {
2320 intf
= ffs_func_revmap_intf(func
, interface
);
2321 if (unlikely(intf
< 0))
2326 ffs_func_eps_disable(ffs
->func
);
2328 if (ffs
->state
!= FFS_ACTIVE
)
2331 if (alt
== (unsigned)-1) {
2333 ffs_event_add(ffs
, FUNCTIONFS_DISABLE
);
2338 ret
= ffs_func_eps_enable(func
);
2339 if (likely(ret
>= 0))
2340 ffs_event_add(ffs
, FUNCTIONFS_ENABLE
);
2344 static void ffs_func_disable(struct usb_function
*f
)
2346 ffs_func_set_alt(f
, 0, (unsigned)-1);
2349 static int ffs_func_setup(struct usb_function
*f
,
2350 const struct usb_ctrlrequest
*creq
)
2352 struct ffs_function
*func
= ffs_func_from_usb(f
);
2353 struct ffs_data
*ffs
= func
->ffs
;
2354 unsigned long flags
;
2359 pr_vdebug("creq->bRequestType = %02x\n", creq
->bRequestType
);
2360 pr_vdebug("creq->bRequest = %02x\n", creq
->bRequest
);
2361 pr_vdebug("creq->wValue = %04x\n", le16_to_cpu(creq
->wValue
));
2362 pr_vdebug("creq->wIndex = %04x\n", le16_to_cpu(creq
->wIndex
));
2363 pr_vdebug("creq->wLength = %04x\n", le16_to_cpu(creq
->wLength
));
2366 * Most requests directed to interface go through here
2367 * (notable exceptions are set/get interface) so we need to
2368 * handle them. All other either handled by composite or
2369 * passed to usb_configuration->setup() (if one is set). No
2370 * matter, we will handle requests directed to endpoint here
2371 * as well (as it's straightforward) but what to do with any
2374 if (ffs
->state
!= FFS_ACTIVE
)
2377 switch (creq
->bRequestType
& USB_RECIP_MASK
) {
2378 case USB_RECIP_INTERFACE
:
2379 ret
= ffs_func_revmap_intf(func
, le16_to_cpu(creq
->wIndex
));
2380 if (unlikely(ret
< 0))
2384 case USB_RECIP_ENDPOINT
:
2385 ret
= ffs_func_revmap_ep(func
, le16_to_cpu(creq
->wIndex
));
2386 if (unlikely(ret
< 0))
2394 spin_lock_irqsave(&ffs
->ev
.waitq
.lock
, flags
);
2395 ffs
->ev
.setup
= *creq
;
2396 ffs
->ev
.setup
.wIndex
= cpu_to_le16(ret
);
2397 __ffs_event_add(ffs
, FUNCTIONFS_SETUP
);
2398 spin_unlock_irqrestore(&ffs
->ev
.waitq
.lock
, flags
);
2403 static void ffs_func_suspend(struct usb_function
*f
)
2406 ffs_event_add(ffs_func_from_usb(f
)->ffs
, FUNCTIONFS_SUSPEND
);
2409 static void ffs_func_resume(struct usb_function
*f
)
2412 ffs_event_add(ffs_func_from_usb(f
)->ffs
, FUNCTIONFS_RESUME
);
2416 /* Endpoint and interface numbers reverse mapping ***************************/
2418 static int ffs_func_revmap_ep(struct ffs_function
*func
, u8 num
)
2420 num
= func
->eps_revmap
[num
& USB_ENDPOINT_NUMBER_MASK
];
2421 return num
? num
: -EDOM
;
2424 static int ffs_func_revmap_intf(struct ffs_function
*func
, u8 intf
)
2426 short *nums
= func
->interfaces_nums
;
2427 unsigned count
= func
->ffs
->interfaces_count
;
2429 for (; count
; --count
, ++nums
) {
2430 if (*nums
>= 0 && *nums
== intf
)
2431 return nums
- func
->interfaces_nums
;
2438 /* Misc helper functions ****************************************************/
2440 static int ffs_mutex_lock(struct mutex
*mutex
, unsigned nonblock
)
2443 ? likely(mutex_trylock(mutex
)) ? 0 : -EAGAIN
2444 : mutex_lock_interruptible(mutex
);
2447 static char *ffs_prepare_buffer(const char __user
*buf
, size_t len
)
2454 data
= kmalloc(len
, GFP_KERNEL
);
2455 if (unlikely(!data
))
2456 return ERR_PTR(-ENOMEM
);
2458 if (unlikely(__copy_from_user(data
, buf
, len
))) {
2460 return ERR_PTR(-EFAULT
);
2463 pr_vdebug("Buffer from user space:\n");
2464 ffs_dump_mem("", data
, len
);