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Fix up trivial spelling errors ('taht' -> 'that')
[GitHub/LineageOS/android_kernel_samsung_universal7580.git] / drivers / usb / gadget / f_fs.c
CommitLineData
ddf8abd2
MN		 1/*
2 * f_fs.c -- user mode filesystem api for usb composite funtcion controllers
3 *
4 * Copyright (C) 2010 Samsung Electronics
5 * Author: Michal Nazarewicz <m.nazarewicz@samsung.com>
6 *
7 * Based on inode.c (GadgetFS):
8 * Copyright (C) 2003-2004 David Brownell
9 * Copyright (C) 2003 Agilent Technologies
10 *
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.
15 *
16 * This program is distributed in the hope that it will be useful,
17 * but WITHOUT ANY WARRANTY; without even the implied warranty of
18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19 * GNU General Public License for more details.
20 *
21 * You should have received a copy of the GNU General Public License
22 * along with this program; if not, write to the Free Software
23 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
24 */
25
26
27/* #define DEBUG */
28/* #define VERBOSE_DEBUG */
29
30#include <linux/blkdev.h>
b0608690 31#include <linux/pagemap.h>
ddf8abd2
MN		 32#include <asm/unaligned.h>
33#include <linux/smp_lock.h>
34
35#include <linux/usb/composite.h>
36#include <linux/usb/functionfs.h>
37
38
39#define FUNCTIONFS_MAGIC 0xa647361 /* Chosen by a honest dice roll ;) */
40
41
42/* Debuging *****************************************************************/
43
44#define ffs_printk(level, fmt, args...) printk(level "f_fs: " fmt "\n", ## args)
45
46#define FERR(...) ffs_printk(KERN_ERR, __VA_ARGS__)
47#define FINFO(...) ffs_printk(KERN_INFO, __VA_ARGS__)
48
49#ifdef DEBUG
50# define FDBG(...) ffs_printk(KERN_DEBUG, __VA_ARGS__)
51#else
52# define FDBG(...) do { } while (0)
53#endif /* DEBUG */
54
55#ifdef VERBOSE_DEBUG
56# define FVDBG FDBG
57#else
58# define FVDBG(...) do { } while (0)
59#endif /* VERBOSE_DEBUG */
60
61#define ENTER() FVDBG("%s()", __func__)
62
63#ifdef VERBOSE_DEBUG
64# define ffs_dump_mem(prefix, ptr, len) \
65 print_hex_dump_bytes("f_fs" prefix ": ", DUMP_PREFIX_NONE, ptr, len)
66#else
67# define ffs_dump_mem(prefix, ptr, len) do { } while (0)
68#endif
69
70
71/* The data structure and setup file ****************************************/
72
73enum ffs_state {
74 /* Waiting for descriptors and strings. */
75 /* In this state no open(2), read(2) or write(2) on epfiles
76 * may succeed (which should not be the problem as there
77 * should be no such files opened in the firts place). */
78 FFS_READ_DESCRIPTORS,
79 FFS_READ_STRINGS,
80
81 /* We've got descriptors and strings. We are or have called
82 * functionfs_ready_callback(). functionfs_bind() may have
83 * been called but we don't know. */
84 /* This is the only state in which operations on epfiles may
85 * succeed. */
86 FFS_ACTIVE,
87
88 /* All endpoints have been closed. This state is also set if
89 * we encounter an unrecoverable error. The only
90 * unrecoverable error is situation when after reading strings
91 * from user space we fail to initialise EP files or
92 * functionfs_ready_callback() returns with error (<0). */
93 /* In this state no open(2), read(2) or write(2) (both on ep0
94 * as well as epfile) may succeed (at this point epfiles are
95 * unlinked and all closed so this is not a problem; ep0 is
96 * also closed but ep0 file exists and so open(2) on ep0 must
97 * fail). */
98 FFS_CLOSING
99};
100
101
102enum ffs_setup_state {
103 /* There is no setup request pending. */
104 FFS_NO_SETUP,
105 /* User has read events and there was a setup request event
106 * there. The next read/write on ep0 will handle the
107 * request. */
108 FFS_SETUP_PENDING,
109 /* There was event pending but before user space handled it
110 * some other event was introduced which canceled existing
111 * setup. If this state is set read/write on ep0 return
112 * -EIDRM. This state is only set when adding event. */
113 FFS_SETUP_CANCELED
114};
115
116
117
118struct ffs_epfile;
119struct ffs_function;
120
121struct ffs_data {
122 struct usb_gadget *gadget;
123
124 /* Protect access read/write operations, only one read/write
125 * at a time. As a consequence protects ep0req and company.
126 * While setup request is being processed (queued) this is
127 * held. */
128 struct mutex mutex;
129
130 /* Protect access to enpoint related structures (basically
131 * usb_ep_queue(), usb_ep_dequeue(), etc. calls) except for
132 * endpint zero. */
133 spinlock_t eps_lock;
134
135 /* XXX REVISIT do we need our own request? Since we are not
136 * handling setup requests immidiatelly user space may be so
137 * slow that another setup will be sent to the gadget but this
138 * time not to us but another function and then there could be
a4ce96ac 139 * a race. Is that the case? Or maybe we can use cdev->req
ddf8abd2
MN		 140 * 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 */
144
145 /* reference counter */
146 atomic_t ref;
147 /* how many files are opened (EP0 and others) */
148 atomic_t opened;
149
150 /* EP0 state */
151 enum ffs_state state;
152
153 /*
154 * Possible transations:
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
161 */
162 enum ffs_setup_state setup_state;
163
164#define FFS_SETUP_STATE(ffs) \
165 ((enum ffs_setup_state)cmpxchg(&(ffs)->setup_state, \
166 FFS_SETUP_CANCELED, FFS_NO_SETUP))
167
168 /* Events & such. */
169 struct {
170 u8 types[4];
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;
175
176 wait_queue_head_t waitq;
177 } ev; /* the whole structure, P: ev.waitq.lock */
178
179 /* Flags */
180 unsigned long flags;
181#define FFS_FL_CALL_CLOSED_CALLBACK 0
182#define FFS_FL_BOUND 1
183
184 /* Active function */
185 struct ffs_function *func;
186
187 /* Device name, write once when file system is mounted.
188 * Intendet for user to read if she wants. */
189 const char *dev_name;
190 /* Private data for our user (ie. gadget). Managed by
191 * user. */
192 void *private_data;
193
194 /* filled by __ffs_data_got_descs() */
195 /* real descriptors are 16 bytes after raw_descs (so you need
196 * to skip 16 bytes (ie. ffs->raw_descs + 16) to get to the
197 * first full speed descriptor). raw_descs_length and
198 * raw_fs_descs_length do not have those 16 bytes added. */
199 const void *raw_descs;
200 unsigned raw_descs_length;
201 unsigned raw_fs_descs_length;
202 unsigned fs_descs_count;
203 unsigned hs_descs_count;
204
205 unsigned short strings_count;
206 unsigned short interfaces_count;
207 unsigned short eps_count;
208 unsigned short _pad1;
209
210 /* filled by __ffs_data_got_strings() */
211 /* ids in stringtabs are set in functionfs_bind() */
212 const void *raw_strings;
213 struct usb_gadget_strings **stringtabs;
214
215 /* File system's super block, write once when file system is mounted. */
216 struct super_block *sb;
217
218 /* File permissions, written once when fs is mounted*/
219 struct ffs_file_perms {
220 umode_t mode;
221 uid_t uid;
222 gid_t gid;
223 } file_perms;
224
225 /* The endpoint files, filled by ffs_epfiles_create(),
226 * destroyed by ffs_epfiles_destroy(). */
227 struct ffs_epfile *epfiles;
228};
229
230/* Reference counter handling */
231static void ffs_data_get(struct ffs_data *ffs);
232static void ffs_data_put(struct ffs_data *ffs);
233/* Creates new ffs_data object. */
234static struct ffs_data *__must_check ffs_data_new(void) __attribute__((malloc));
235
236/* Opened counter handling. */
237static void ffs_data_opened(struct ffs_data *ffs);
238static void ffs_data_closed(struct ffs_data *ffs);
239
240/* Called with ffs->mutex held; take over ownerrship of data. */
241static int __must_check
242__ffs_data_got_descs(struct ffs_data *ffs, char *data, size_t len);
243static int __must_check
244__ffs_data_got_strings(struct ffs_data *ffs, char *data, size_t len);
245
246
247/* The function structure ***************************************************/
248
249struct ffs_ep;
250
251struct ffs_function {
252 struct usb_configuration *conf;
253 struct usb_gadget *gadget;
254 struct ffs_data *ffs;
255
256 struct ffs_ep *eps;
257 u8 eps_revmap[16];
258 short *interfaces_nums;
259
260 struct usb_function function;
261};
262
263
264static struct ffs_function *ffs_func_from_usb(struct usb_function *f)
265{
266 return container_of(f, struct ffs_function, function);
267}
268
269static void ffs_func_free(struct ffs_function *func);
270
271
272static void ffs_func_eps_disable(struct ffs_function *func);
273static int __must_check ffs_func_eps_enable(struct ffs_function *func);
274
275
276static int ffs_func_bind(struct usb_configuration *,
277 struct usb_function *);
278static void ffs_func_unbind(struct usb_configuration *,
279 struct usb_function *);
280static int ffs_func_set_alt(struct usb_function *, unsigned, unsigned);
281static void ffs_func_disable(struct usb_function *);
282static int ffs_func_setup(struct usb_function *,
283 const struct usb_ctrlrequest *);
284static void ffs_func_suspend(struct usb_function *);
285static void ffs_func_resume(struct usb_function *);
286
287
288static int ffs_func_revmap_ep(struct ffs_function *func, u8 num);
289static int ffs_func_revmap_intf(struct ffs_function *func, u8 intf);
290
291
292
293/* The endpoints structures *************************************************/
294
295struct ffs_ep {
296 struct usb_ep *ep; /* P: ffs->eps_lock */
297 struct usb_request *req; /* P: epfile->mutex */
298
299 /* [0]: full speed, [1]: high speed */
300 struct usb_endpoint_descriptor *descs[2];
301
302 u8 num;
303
304 int status; /* P: epfile->mutex */
305};
306
307struct ffs_epfile {
308 /* Protects ep->ep and ep->req. */
309 struct mutex mutex;
310 wait_queue_head_t wait;
311
312 struct ffs_data *ffs;
313 struct ffs_ep *ep; /* P: ffs->eps_lock */
314
315 struct dentry *dentry;
316
317 char name[5];
318
319 unsigned char in; /* P: ffs->eps_lock */
320 unsigned char isoc; /* P: ffs->eps_lock */
321
322 unsigned char _pad;
323};
324
325
326static int __must_check ffs_epfiles_create(struct ffs_data *ffs);
327static void ffs_epfiles_destroy(struct ffs_epfile *epfiles, unsigned count);
328
329static struct inode *__must_check
330ffs_sb_create_file(struct super_block *sb, const char *name, void *data,
331 const struct file_operations *fops,
332 struct dentry **dentry_p);
333
334
335/* Misc helper functions ****************************************************/
336
337static int ffs_mutex_lock(struct mutex *mutex, unsigned nonblock)
338 __attribute__((warn_unused_result, nonnull));
339static char *ffs_prepare_buffer(const char * __user buf, size_t len)
340 __attribute__((warn_unused_result, nonnull));
341
342
343/* Control file aka ep0 *****************************************************/
344
345static void ffs_ep0_complete(struct usb_ep *ep, struct usb_request *req)
346{
347 struct ffs_data *ffs = req->context;
348
349 complete_all(&ffs->ep0req_completion);
350}
351
352
353static int __ffs_ep0_queue_wait(struct ffs_data *ffs, char *data, size_t len)
354{
355 struct usb_request *req = ffs->ep0req;
356 int ret;
357
358 req->zero = len < le16_to_cpu(ffs->ev.setup.wLength);
359
360 spin_unlock_irq(&ffs->ev.waitq.lock);
361
362 req->buf = data;
363 req->length = len;
364
365 INIT_COMPLETION(ffs->ep0req_completion);
366
367 ret = usb_ep_queue(ffs->gadget->ep0, req, GFP_ATOMIC);
368 if (unlikely(ret < 0))
369 return ret;
370
371 ret = wait_for_completion_interruptible(&ffs->ep0req_completion);
372 if (unlikely(ret)) {
373 usb_ep_dequeue(ffs->gadget->ep0, req);
374 return -EINTR;
375 }
376
377 ffs->setup_state = FFS_NO_SETUP;
378 return ffs->ep0req_status;
379}
380
381static int __ffs_ep0_stall(struct ffs_data *ffs)
382{
383 if (ffs->ev.can_stall) {
384 FVDBG("ep0 stall\n");
385 usb_ep_set_halt(ffs->gadget->ep0);
386 ffs->setup_state = FFS_NO_SETUP;
387 return -EL2HLT;
388 } else {
389 FDBG("bogus ep0 stall!\n");
390 return -ESRCH;
391 }
392}
393
394
395static ssize_t ffs_ep0_write(struct file *file, const char __user *buf,
396 size_t len, loff_t *ptr)
397{
398 struct ffs_data *ffs = file->private_data;
399 ssize_t ret;
400 char *data;
401
402 ENTER();
403
404 /* Fast check if setup was canceled */
405 if (FFS_SETUP_STATE(ffs) == FFS_SETUP_CANCELED)
406 return -EIDRM;
407
408 /* Acquire mutex */
409 ret = ffs_mutex_lock(&ffs->mutex, file->f_flags & O_NONBLOCK);
410 if (unlikely(ret < 0))
411 return ret;
412
413
414 /* Check state */
415 switch (ffs->state) {
416 case FFS_READ_DESCRIPTORS:
417 case FFS_READ_STRINGS:
418 /* Copy data */
419 if (unlikely(len < 16)) {
420 ret = -EINVAL;
421 break;
422 }
423
424 data = ffs_prepare_buffer(buf, len);
425 if (unlikely(IS_ERR(data))) {
426 ret = PTR_ERR(data);
427 break;
428 }
429
430 /* Handle data */
431 if (ffs->state == FFS_READ_DESCRIPTORS) {
432 FINFO("read descriptors");
433 ret = __ffs_data_got_descs(ffs, data, len);
434 if (unlikely(ret < 0))
435 break;
436
437 ffs->state = FFS_READ_STRINGS;
438 ret = len;
439 } else {
440 FINFO("read strings");
441 ret = __ffs_data_got_strings(ffs, data, len);
442 if (unlikely(ret < 0))
443 break;
444
445 ret = ffs_epfiles_create(ffs);
446 if (unlikely(ret)) {
447 ffs->state = FFS_CLOSING;
448 break;
449 }
450
451 ffs->state = FFS_ACTIVE;
452 mutex_unlock(&ffs->mutex);
453
454 ret = functionfs_ready_callback(ffs);
455 if (unlikely(ret < 0)) {
456 ffs->state = FFS_CLOSING;
457 return ret;
458 }
459
460 set_bit(FFS_FL_CALL_CLOSED_CALLBACK, &ffs->flags);
461 return len;
462 }
463 break;
464
465
466 case FFS_ACTIVE:
467 data = NULL;
468 /* We're called from user space, we can use _irq
469 * rather then _irqsave */
470 spin_lock_irq(&ffs->ev.waitq.lock);
471 switch (FFS_SETUP_STATE(ffs)) {
472 case FFS_SETUP_CANCELED:
473 ret = -EIDRM;
474 goto done_spin;
475
476 case FFS_NO_SETUP:
477 ret = -ESRCH;
478 goto done_spin;
479
480 case FFS_SETUP_PENDING:
481 break;
482 }
483
484 /* FFS_SETUP_PENDING */
485 if (!(ffs->ev.setup.bRequestType & USB_DIR_IN)) {
486 spin_unlock_irq(&ffs->ev.waitq.lock);
487 ret = __ffs_ep0_stall(ffs);
488 break;
489 }
490
491 /* FFS_SETUP_PENDING and not stall */
492 len = min(len, (size_t)le16_to_cpu(ffs->ev.setup.wLength));
493
494 spin_unlock_irq(&ffs->ev.waitq.lock);
495
496 data = ffs_prepare_buffer(buf, len);
497 if (unlikely(IS_ERR(data))) {
498 ret = PTR_ERR(data);
499 break;
500 }
501
502 spin_lock_irq(&ffs->ev.waitq.lock);
503
504 /* We are guaranteed to be still in FFS_ACTIVE state
505 * but the state of setup could have changed from
506 * FFS_SETUP_PENDING to FFS_SETUP_CANCELED so we need
507 * to check for that. If that happened we copied data
508 * from user space in vain but it's unlikely. */
509 /* For sure we are not in FFS_NO_SETUP since this is
510 * the only place FFS_SETUP_PENDING -> FFS_NO_SETUP
511 * transition can be performed and it's protected by
512 * mutex. */
513
514 if (FFS_SETUP_STATE(ffs) == FFS_SETUP_CANCELED) {
515 ret = -EIDRM;
516done_spin:
517 spin_unlock_irq(&ffs->ev.waitq.lock);
518 } else {
519 /* unlocks spinlock */
520 ret = __ffs_ep0_queue_wait(ffs, data, len);
521 }
522 kfree(data);
523 break;
524
525
526 default:
527 ret = -EBADFD;
528 break;
529 }
530
531
532 mutex_unlock(&ffs->mutex);
533 return ret;
534}
535
536
537
538static ssize_t __ffs_ep0_read_events(struct ffs_data *ffs, char __user *buf,
539 size_t n)
540{
541 /* We are holding ffs->ev.waitq.lock and ffs->mutex and we need
542 * to release them. */
543
544 struct usb_functionfs_event events[n];
545 unsigned i = 0;
546
547 memset(events, 0, sizeof events);
548
549 do {
550 events[i].type = ffs->ev.types[i];
551 if (events[i].type == FUNCTIONFS_SETUP) {
552 events[i].u.setup = ffs->ev.setup;
553 ffs->setup_state = FFS_SETUP_PENDING;
554 }
555 } while (++i < n);
556
557 if (n < ffs->ev.count) {
558 ffs->ev.count -= n;
559 memmove(ffs->ev.types, ffs->ev.types + n,
560 ffs->ev.count * sizeof *ffs->ev.types);
561 } else {
562 ffs->ev.count = 0;
563 }
564
565 spin_unlock_irq(&ffs->ev.waitq.lock);
566 mutex_unlock(&ffs->mutex);
567
568 return unlikely(__copy_to_user(buf, events, sizeof events))
569 ? -EFAULT : sizeof events;
570}
571
572
573static ssize_t ffs_ep0_read(struct file *file, char __user *buf,
574 size_t len, loff_t *ptr)
575{
576 struct ffs_data *ffs = file->private_data;
577 char *data = NULL;
578 size_t n;
579 int ret;
580
581 ENTER();
582
583 /* Fast check if setup was canceled */
584 if (FFS_SETUP_STATE(ffs) == FFS_SETUP_CANCELED)
585 return -EIDRM;
586
587 /* Acquire mutex */
588 ret = ffs_mutex_lock(&ffs->mutex, file->f_flags & O_NONBLOCK);
589 if (unlikely(ret < 0))
590 return ret;
591
592
593 /* Check state */
594 if (ffs->state != FFS_ACTIVE) {
595 ret = -EBADFD;
596 goto done_mutex;
597 }
598
599
600 /* We're called from user space, we can use _irq rather then
601 * _irqsave */
602 spin_lock_irq(&ffs->ev.waitq.lock);
603
604 switch (FFS_SETUP_STATE(ffs)) {
605 case FFS_SETUP_CANCELED:
606 ret = -EIDRM;
607 break;
608
609 case FFS_NO_SETUP:
610 n = len / sizeof(struct usb_functionfs_event);
611 if (unlikely(!n)) {
612 ret = -EINVAL;
613 break;
614 }
615
616 if ((file->f_flags & O_NONBLOCK) && !ffs->ev.count) {
617 ret = -EAGAIN;
618 break;
619 }
620
621 if (unlikely(wait_event_interruptible_exclusive_locked_irq(ffs->ev.waitq, ffs->ev.count))) {
622 ret = -EINTR;
623 break;
624 }
625
626 return __ffs_ep0_read_events(ffs, buf,
627 min(n, (size_t)ffs->ev.count));
628
629
630 case FFS_SETUP_PENDING:
631 if (ffs->ev.setup.bRequestType & USB_DIR_IN) {
632 spin_unlock_irq(&ffs->ev.waitq.lock);
633 ret = __ffs_ep0_stall(ffs);
634 goto done_mutex;
635 }
636
637 len = min(len, (size_t)le16_to_cpu(ffs->ev.setup.wLength));
638
639 spin_unlock_irq(&ffs->ev.waitq.lock);
640
641 if (likely(len)) {
642 data = kmalloc(len, GFP_KERNEL);
643 if (unlikely(!data)) {
644 ret = -ENOMEM;
645 goto done_mutex;
646 }
647 }
648
649 spin_lock_irq(&ffs->ev.waitq.lock);
650
651 /* See ffs_ep0_write() */
652 if (FFS_SETUP_STATE(ffs) == FFS_SETUP_CANCELED) {
653 ret = -EIDRM;
654 break;
655 }
656
657 /* unlocks spinlock */
658 ret = __ffs_ep0_queue_wait(ffs, data, len);
659 if (likely(ret > 0) && unlikely(__copy_to_user(buf, data, len)))
660 ret = -EFAULT;
661 goto done_mutex;
662
663 default:
664 ret = -EBADFD;
665 break;
666 }
667
668 spin_unlock_irq(&ffs->ev.waitq.lock);
669done_mutex:
670 mutex_unlock(&ffs->mutex);
671 kfree(data);
672 return ret;
673}
674
675
676
677static int ffs_ep0_open(struct inode *inode, struct file *file)
678{
679 struct ffs_data *ffs = inode->i_private;
680
681 ENTER();
682
683 if (unlikely(ffs->state == FFS_CLOSING))
684 return -EBUSY;
685
686 file->private_data = ffs;
687 ffs_data_opened(ffs);
688
689 return 0;
690}
691
692
693static int ffs_ep0_release(struct inode *inode, struct file *file)
694{
695 struct ffs_data *ffs = file->private_data;
696
697 ENTER();
698
699 ffs_data_closed(ffs);
700
701 return 0;
702}
703
704
705static long ffs_ep0_ioctl(struct file *file, unsigned code, unsigned long value)
706{
707 struct ffs_data *ffs = file->private_data;
708 struct usb_gadget *gadget = ffs->gadget;
709 long ret;
710
711 ENTER();
712
713 if (code == FUNCTIONFS_INTERFACE_REVMAP) {
714 struct ffs_function *func = ffs->func;
715 ret = func ? ffs_func_revmap_intf(func, value) : -ENODEV;
716 } else if (gadget->ops->ioctl) {
717 lock_kernel();
718 ret = gadget->ops->ioctl(gadget, code, value);
719 unlock_kernel();
720 } else {
721 ret = -ENOTTY;
722 }
723
724 return ret;
725}
726
727
728static const struct file_operations ffs_ep0_operations = {
729 .owner = THIS_MODULE,
730 .llseek = no_llseek,
731
732 .open = ffs_ep0_open,
733 .write = ffs_ep0_write,
734 .read = ffs_ep0_read,
735 .release = ffs_ep0_release,
736 .unlocked_ioctl = ffs_ep0_ioctl,
737};
738
739
740/* "Normal" endpoints operations ********************************************/
741
742
743static void ffs_epfile_io_complete(struct usb_ep *_ep, struct usb_request *req)
744{
745 ENTER();
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);
750 }
751}
752
753
754static ssize_t ffs_epfile_io(struct file *file,
755 char __user *buf, size_t len, int read)
756{
757 struct ffs_epfile *epfile = file->private_data;
758 struct ffs_ep *ep;
759 char *data = NULL;
760 ssize_t ret;
761 int halt;
762
763 goto first_try;
764 do {
765 spin_unlock_irq(&epfile->ffs->eps_lock);
766 mutex_unlock(&epfile->mutex);
767
768first_try:
769 /* Are we still active? */
770 if (WARN_ON(epfile->ffs->state != FFS_ACTIVE)) {
771 ret = -ENODEV;
772 goto error;
773 }
774
775 /* Wait for endpoint to be enabled */
776 ep = epfile->ep;
777 if (!ep) {
778 if (file->f_flags & O_NONBLOCK) {
779 ret = -EAGAIN;
780 goto error;
781 }
782
783 if (unlikely(wait_event_interruptible
784 (epfile->wait, (ep = epfile->ep)))) {
785 ret = -EINTR;
786 goto error;
787 }
788 }
789
790 /* Do we halt? */
791 halt = !read == !epfile->in;
792 if (halt && epfile->isoc) {
793 ret = -EINVAL;
794 goto error;
795 }
796
797 /* Allocate & copy */
798 if (!halt && !data) {
799 data = kzalloc(len, GFP_KERNEL);
800 if (unlikely(!data))
801 return -ENOMEM;
802
803 if (!read &&
804 unlikely(__copy_from_user(data, buf, len))) {
805 ret = -EFAULT;
806 goto error;
807 }
808 }
809
810 /* We will be using request */
811 ret = ffs_mutex_lock(&epfile->mutex,
812 file->f_flags & O_NONBLOCK);
813 if (unlikely(ret))
814 goto error;
815
816 /* We're called from user space, we can use _irq rather then
817 * _irqsave */
818 spin_lock_irq(&epfile->ffs->eps_lock);
819
820 /* While we were acquiring mutex endpoint got disabled
821 * or changed? */
822 } while (unlikely(epfile->ep != ep));
823
824 /* Halt */
825 if (unlikely(halt)) {
826 if (likely(epfile->ep == ep) && !WARN_ON(!ep->ep))
827 usb_ep_set_halt(ep->ep);
828 spin_unlock_irq(&epfile->ffs->eps_lock);
829 ret = -EBADMSG;
830 } else {
831 /* Fire the request */
832 DECLARE_COMPLETION_ONSTACK(done);
833
834 struct usb_request *req = ep->req;
835 req->context = &done;
836 req->complete = ffs_epfile_io_complete;
837 req->buf = data;
838 req->length = len;
839
840 ret = usb_ep_queue(ep->ep, req, GFP_ATOMIC);
841
842 spin_unlock_irq(&epfile->ffs->eps_lock);
843
844 if (unlikely(ret < 0)) {
845 /* nop */
846 } else if (unlikely(wait_for_completion_interruptible(&done))) {
847 ret = -EINTR;
848 usb_ep_dequeue(ep->ep, req);
849 } else {
850 ret = ep->status;
851 if (read && ret > 0 &&
852 unlikely(copy_to_user(buf, data, ret)))
853 ret = -EFAULT;
854 }
855 }
856
857 mutex_unlock(&epfile->mutex);
858error:
859 kfree(data);
860 return ret;
861}
862
863
864static ssize_t
865ffs_epfile_write(struct file *file, const char __user *buf, size_t len,
866 loff_t *ptr)
867{
868 ENTER();
869
870 return ffs_epfile_io(file, (char __user *)buf, len, 0);
871}
872
873static ssize_t
874ffs_epfile_read(struct file *file, char __user *buf, size_t len, loff_t *ptr)
875{
876 ENTER();
877
878 return ffs_epfile_io(file, buf, len, 1);
879}
880
881static int
882ffs_epfile_open(struct inode *inode, struct file *file)
883{
884 struct ffs_epfile *epfile = inode->i_private;
885
886 ENTER();
887
888 if (WARN_ON(epfile->ffs->state != FFS_ACTIVE))
889 return -ENODEV;
890
891 file->private_data = epfile;
892 ffs_data_opened(epfile->ffs);
893
894 return 0;
895}
896
897static int
898ffs_epfile_release(struct inode *inode, struct file *file)
899{
900 struct ffs_epfile *epfile = inode->i_private;
901
902 ENTER();
903
904 ffs_data_closed(epfile->ffs);
905
906 return 0;
907}
908
909
910static long ffs_epfile_ioctl(struct file *file, unsigned code,
911 unsigned long value)
912{
913 struct ffs_epfile *epfile = file->private_data;
914 int ret;
915
916 ENTER();
917
918 if (WARN_ON(epfile->ffs->state != FFS_ACTIVE))
919 return -ENODEV;
920
921 spin_lock_irq(&epfile->ffs->eps_lock);
922 if (likely(epfile->ep)) {
923 switch (code) {
924 case FUNCTIONFS_FIFO_STATUS:
925 ret = usb_ep_fifo_status(epfile->ep->ep);
926 break;
927 case FUNCTIONFS_FIFO_FLUSH:
928 usb_ep_fifo_flush(epfile->ep->ep);
929 ret = 0;
930 break;
931 case FUNCTIONFS_CLEAR_HALT:
932 ret = usb_ep_clear_halt(epfile->ep->ep);
933 break;
934 case FUNCTIONFS_ENDPOINT_REVMAP:
935 ret = epfile->ep->num;
936 break;
937 default:
938 ret = -ENOTTY;
939 }
940 } else {
941 ret = -ENODEV;
942 }
943 spin_unlock_irq(&epfile->ffs->eps_lock);
944
945 return ret;
946}
947
948
949static const struct file_operations ffs_epfile_operations = {
950 .owner = THIS_MODULE,
951 .llseek = no_llseek,
952
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,
958};
959
960
961
962/* File system and super block operations ***********************************/
963
964/*
965 * Mounting the filesystem creates a controller file, used first for
966 * function configuration then later for event monitoring.
967 */
968
969
970static struct inode *__must_check
971ffs_sb_make_inode(struct super_block *sb, void *data,
972 const struct file_operations *fops,
973 const struct inode_operations *iops,
974 struct ffs_file_perms *perms)
975{
976 struct inode *inode;
977
978 ENTER();
979
980 inode = new_inode(sb);
981
982 if (likely(inode)) {
983 struct timespec current_time = CURRENT_TIME;
984
985 inode->i_mode = perms->mode;
986 inode->i_uid = perms->uid;
987 inode->i_gid = perms->gid;
988 inode->i_atime = current_time;
989 inode->i_mtime = current_time;
990 inode->i_ctime = current_time;
991 inode->i_private = data;
992 if (fops)
993 inode->i_fop = fops;
994 if (iops)
995 inode->i_op = iops;
996 }
997
998 return inode;
999}
1000
1001
1002/* Create "regular" file */
1003
1004static struct inode *ffs_sb_create_file(struct super_block *sb,
1005 const char *name, void *data,
1006 const struct file_operations *fops,
1007 struct dentry **dentry_p)
1008{
1009 struct ffs_data *ffs = sb->s_fs_info;
1010 struct dentry *dentry;
1011 struct inode *inode;
1012
1013 ENTER();
1014
1015 dentry = d_alloc_name(sb->s_root, name);
1016 if (unlikely(!dentry))
1017 return NULL;
1018
1019 inode = ffs_sb_make_inode(sb, data, fops, NULL, &ffs->file_perms);
1020 if (unlikely(!inode)) {
1021 dput(dentry);
1022 return NULL;
1023 }
1024
1025 d_add(dentry, inode);
1026 if (dentry_p)
1027 *dentry_p = dentry;
1028
1029 return inode;
1030}
1031
1032
1033/* Super block */
1034
1035static const struct super_operations ffs_sb_operations = {
1036 .statfs = simple_statfs,
1037 .drop_inode = generic_delete_inode,
1038};
1039
1040struct ffs_sb_fill_data {
1041 struct ffs_file_perms perms;
1042 umode_t root_mode;
1043 const char *dev_name;
1044};
1045
1046static int ffs_sb_fill(struct super_block *sb, void *_data, int silent)
1047{
1048 struct ffs_sb_fill_data *data = _data;
1049 struct inode *inode;
1050 struct dentry *d;
1051 struct ffs_data *ffs;
1052
1053 ENTER();
1054
1055 /* Initialize data */
1056 ffs = ffs_data_new();
1057 if (unlikely(!ffs))
1058 goto enomem0;
1059
1060 ffs->sb = sb;
1061 ffs->dev_name = data->dev_name;
1062 ffs->file_perms = data->perms;
1063
1064 sb->s_fs_info = ffs;
1065 sb->s_blocksize = PAGE_CACHE_SIZE;
1066 sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
1067 sb->s_magic = FUNCTIONFS_MAGIC;
1068 sb->s_op = &ffs_sb_operations;
1069 sb->s_time_gran = 1;
1070
1071 /* Root inode */
1072 data->perms.mode = data->root_mode;
1073 inode = ffs_sb_make_inode(sb, NULL,
1074 &simple_dir_operations,
1075 &simple_dir_inode_operations,
1076 &data->perms);
1077 if (unlikely(!inode))
1078 goto enomem1;
1079 d = d_alloc_root(inode);
1080 if (unlikely(!d))
1081 goto enomem2;
1082 sb->s_root = d;
1083
1084 /* EP0 file */
1085 if (unlikely(!ffs_sb_create_file(sb, "ep0", ffs,
1086 &ffs_ep0_operations, NULL)))
1087 goto enomem3;
1088
1089 return 0;
1090
1091enomem3:
1092 dput(d);
1093enomem2:
1094 iput(inode);
1095enomem1:
1096 ffs_data_put(ffs);
1097enomem0:
1098 return -ENOMEM;
1099}
1100
1101
1102static int ffs_fs_parse_opts(struct ffs_sb_fill_data *data, char *opts)
1103{
1104 ENTER();
1105
1106 if (!opts || !*opts)
1107 return 0;
1108
1109 for (;;) {
1110 char *end, *eq, *comma;
1111 unsigned long value;
1112
1113 /* Option limit */
1114 comma = strchr(opts, ',');
1115 if (comma)
1116 *comma = 0;
1117
1118 /* Value limit */
1119 eq = strchr(opts, '=');
1120 if (unlikely(!eq)) {
1121 FERR("'=' missing in %s", opts);
1122 return -EINVAL;
1123 }
1124 *eq = 0;
1125
1126 /* Parse value */
1127 value = simple_strtoul(eq + 1, &end, 0);
1128 if (unlikely(*end != ',' && *end != 0)) {
1129 FERR("%s: invalid value: %s", opts, eq + 1);
1130 return -EINVAL;
1131 }
1132
1133 /* Interpret option */
1134 switch (eq - opts) {
1135 case 5:
1136 if (!memcmp(opts, "rmode", 5))
1137 data->root_mode = (value & 0555) | S_IFDIR;
1138 else if (!memcmp(opts, "fmode", 5))
1139 data->perms.mode = (value & 0666) | S_IFREG;
1140 else
1141 goto invalid;
1142 break;
1143
1144 case 4:
1145 if (!memcmp(opts, "mode", 4)) {
1146 data->root_mode = (value & 0555) | S_IFDIR;
1147 data->perms.mode = (value & 0666) | S_IFREG;
1148 } else {
1149 goto invalid;
1150 }
1151 break;
1152
1153 case 3:
1154 if (!memcmp(opts, "uid", 3))
1155 data->perms.uid = value;
1156 else if (!memcmp(opts, "gid", 3))
1157 data->perms.gid = value;
1158 else
1159 goto invalid;
1160 break;
1161
1162 default:
1163invalid:
1164 FERR("%s: invalid option", opts);
1165 return -EINVAL;
1166 }
1167
1168 /* Next iteration */
1169 if (!comma)
1170 break;
1171 opts = comma + 1;
1172 }
1173
1174 return 0;
1175}
1176
1177
1178/* "mount -t functionfs dev_name /dev/function" ends up here */
1179
1180static int
1181ffs_fs_get_sb(struct file_system_type *t, int flags,
1182 const char *dev_name, void *opts, struct vfsmount *mnt)
1183{
1184 struct ffs_sb_fill_data data = {
1185 .perms = {
1186 .mode = S_IFREG | 0600,
1187 .uid = 0,
1188 .gid = 0
1189 },
1190 .root_mode = S_IFDIR | 0500,
1191 };
1192 int ret;
1193
1194 ENTER();
1195
1196 ret = functionfs_check_dev_callback(dev_name);
1197 if (unlikely(ret < 0))
1198 return ret;
1199
1200 ret = ffs_fs_parse_opts(&data, opts);
1201 if (unlikely(ret < 0))
1202 return ret;
1203
1204 data.dev_name = dev_name;
1205 return get_sb_single(t, flags, &data, ffs_sb_fill, mnt);
1206}
1207
1208static void
1209ffs_fs_kill_sb(struct super_block *sb)
1210{
1211 void *ptr;
1212
1213 ENTER();
1214
1215 kill_litter_super(sb);
1216 ptr = xchg(&sb->s_fs_info, NULL);
1217 if (ptr)
1218 ffs_data_put(ptr);
1219}
1220
1221static struct file_system_type ffs_fs_type = {
1222 .owner = THIS_MODULE,
1223 .name = "functionfs",
1224 .get_sb = ffs_fs_get_sb,
1225 .kill_sb = ffs_fs_kill_sb,
1226};
1227
1228
1229
1230/* Driver's main init/cleanup functions *************************************/
1231
1232
1233static int functionfs_init(void)
1234{
1235 int ret;
1236
1237 ENTER();
1238
1239 ret = register_filesystem(&ffs_fs_type);
1240 if (likely(!ret))
1241 FINFO("file system registered");
1242 else
1243 FERR("failed registering file system (%d)", ret);
1244
1245 return ret;
1246}
1247
1248static void functionfs_cleanup(void)
1249{
1250 ENTER();
1251
1252 FINFO("unloading");
1253 unregister_filesystem(&ffs_fs_type);
1254}
1255
1256
1257
1258/* ffs_data and ffs_function construction and destruction code **************/
1259
1260static void ffs_data_clear(struct ffs_data *ffs);
1261static void ffs_data_reset(struct ffs_data *ffs);
1262
1263
1264static void ffs_data_get(struct ffs_data *ffs)
1265{
1266 ENTER();
1267
1268 atomic_inc(&ffs->ref);
1269}
1270
1271static void ffs_data_opened(struct ffs_data *ffs)
1272{
1273 ENTER();
1274
1275 atomic_inc(&ffs->ref);
1276 atomic_inc(&ffs->opened);
1277}
1278
1279static void ffs_data_put(struct ffs_data *ffs)
1280{
1281 ENTER();
1282
1283 if (unlikely(atomic_dec_and_test(&ffs->ref))) {
1284 FINFO("%s(): freeing", __func__);
1285 ffs_data_clear(ffs);
1286 BUG_ON(mutex_is_locked(&ffs->mutex) ||
1287 spin_is_locked(&ffs->ev.waitq.lock) ||
1288 waitqueue_active(&ffs->ev.waitq) ||
1289 waitqueue_active(&ffs->ep0req_completion.wait));
1290 kfree(ffs);
1291 }
1292}
1293
1294
1295
1296static void ffs_data_closed(struct ffs_data *ffs)
1297{
1298 ENTER();
1299
1300 if (atomic_dec_and_test(&ffs->opened)) {
1301 ffs->state = FFS_CLOSING;
1302 ffs_data_reset(ffs);
1303 }
1304
1305 ffs_data_put(ffs);
1306}
1307
1308
1309static struct ffs_data *ffs_data_new(void)
1310{
1311 struct ffs_data *ffs = kzalloc(sizeof *ffs, GFP_KERNEL);
1312 if (unlikely(!ffs))
1313 return 0;
1314
1315 ENTER();
1316
1317 atomic_set(&ffs->ref, 1);
1318 atomic_set(&ffs->opened, 0);
1319 ffs->state = FFS_READ_DESCRIPTORS;
1320 mutex_init(&ffs->mutex);
1321 spin_lock_init(&ffs->eps_lock);
1322 init_waitqueue_head(&ffs->ev.waitq);
1323 init_completion(&ffs->ep0req_completion);
1324
1325 /* XXX REVISIT need to update it in some places, or do we? */
1326 ffs->ev.can_stall = 1;
1327
1328 return ffs;
1329}
1330
1331
1332static void ffs_data_clear(struct ffs_data *ffs)
1333{
1334 ENTER();
1335
1336 if (test_and_clear_bit(FFS_FL_CALL_CLOSED_CALLBACK, &ffs->flags))
1337 functionfs_closed_callback(ffs);
1338
1339 BUG_ON(ffs->gadget);
1340
1341 if (ffs->epfiles)
1342 ffs_epfiles_destroy(ffs->epfiles, ffs->eps_count);
1343
1344 kfree(ffs->raw_descs);
1345 kfree(ffs->raw_strings);
1346 kfree(ffs->stringtabs);
1347}
1348
1349
1350static void ffs_data_reset(struct ffs_data *ffs)
1351{
1352 ENTER();
1353
1354 ffs_data_clear(ffs);
1355
1356 ffs->epfiles = NULL;
1357 ffs->raw_descs = NULL;
1358 ffs->raw_strings = NULL;
1359 ffs->stringtabs = NULL;
1360
1361 ffs->raw_descs_length = 0;
1362 ffs->raw_fs_descs_length = 0;
1363 ffs->fs_descs_count = 0;
1364 ffs->hs_descs_count = 0;
1365
1366 ffs->strings_count = 0;
1367 ffs->interfaces_count = 0;
1368 ffs->eps_count = 0;
1369
1370 ffs->ev.count = 0;
1371
1372 ffs->state = FFS_READ_DESCRIPTORS;
1373 ffs->setup_state = FFS_NO_SETUP;
1374 ffs->flags = 0;
1375}
1376
1377
1378static int functionfs_bind(struct ffs_data *ffs, struct usb_composite_dev *cdev)
1379{
1380 unsigned i, count;
1381
1382 ENTER();
1383
1384 if (WARN_ON(ffs->state != FFS_ACTIVE
1385 || test_and_set_bit(FFS_FL_BOUND, &ffs->flags)))
1386 return -EBADFD;
1387
1388 ffs_data_get(ffs);
1389
1390 ffs->ep0req = usb_ep_alloc_request(cdev->gadget->ep0, GFP_KERNEL);
1391 if (unlikely(!ffs->ep0req))
1392 return -ENOMEM;
1393 ffs->ep0req->complete = ffs_ep0_complete;
1394 ffs->ep0req->context = ffs;
1395
1396 /* Get strings identifiers */
1397 for (count = ffs->strings_count, i = 0; i < count; ++i) {
1398 struct usb_gadget_strings **lang;
1399
1400 int id = usb_string_id(cdev);
1401 if (unlikely(id < 0)) {
1402 usb_ep_free_request(cdev->gadget->ep0, ffs->ep0req);
1403 ffs->ep0req = NULL;
1404 return id;
1405 }
1406
1407 lang = ffs->stringtabs;
1408 do {
1409 (*lang)->strings[i].id = id;
1410 ++lang;
1411 } while (*lang);
1412 }
1413
1414 ffs->gadget = cdev->gadget;
1415 return 0;
1416}
1417
1418
1419static void functionfs_unbind(struct ffs_data *ffs)
1420{
1421 ENTER();
1422
1423 if (!WARN_ON(!ffs->gadget)) {
1424 usb_ep_free_request(ffs->gadget->ep0, ffs->ep0req);
1425 ffs->ep0req = NULL;
1426 ffs->gadget = NULL;
1427 ffs_data_put(ffs);
1428 }
1429}
1430
1431
1432static int ffs_epfiles_create(struct ffs_data *ffs)
1433{
1434 struct ffs_epfile *epfile, *epfiles;
1435 unsigned i, count;
1436
1437 ENTER();
1438
1439 count = ffs->eps_count;
1440 epfiles = kzalloc(count * sizeof *epfiles, GFP_KERNEL);
1441 if (!epfiles)
1442 return -ENOMEM;
1443
1444 epfile = epfiles;
1445 for (i = 1; i <= count; ++i, ++epfile) {
1446 epfile->ffs = ffs;
1447 mutex_init(&epfile->mutex);
1448 init_waitqueue_head(&epfile->wait);
1449 sprintf(epfiles->name, "ep%u", i);
1450 if (!unlikely(ffs_sb_create_file(ffs->sb, epfiles->name, epfile,
1451 &ffs_epfile_operations,
1452 &epfile->dentry))) {
1453 ffs_epfiles_destroy(epfiles, i - 1);
1454 return -ENOMEM;
1455 }
1456 }
1457
1458 ffs->epfiles = epfiles;
1459 return 0;
1460}
1461
1462
1463static void ffs_epfiles_destroy(struct ffs_epfile *epfiles, unsigned count)
1464{
1465 struct ffs_epfile *epfile = epfiles;
1466
1467 ENTER();
1468
1469 for (; count; --count, ++epfile) {
1470 BUG_ON(mutex_is_locked(&epfile->mutex) ||
1471 waitqueue_active(&epfile->wait));
1472 if (epfile->dentry) {
1473 d_delete(epfile->dentry);
1474 dput(epfile->dentry);
1475 epfile->dentry = NULL;
1476 }
1477 }
1478
1479 kfree(epfiles);
1480}
1481
1482
1483static int functionfs_add(struct usb_composite_dev *cdev,
1484 struct usb_configuration *c,
1485 struct ffs_data *ffs)
1486{
1487 struct ffs_function *func;
1488 int ret;
1489
1490 ENTER();
1491
1492 func = kzalloc(sizeof *func, GFP_KERNEL);
1493 if (unlikely(!func))
1494 return -ENOMEM;
1495
1496 func->function.name = "Function FS Gadget";
1497 func->function.strings = ffs->stringtabs;
1498
1499 func->function.bind = ffs_func_bind;
1500 func->function.unbind = ffs_func_unbind;
1501 func->function.set_alt = ffs_func_set_alt;
1502 /*func->function.get_alt = ffs_func_get_alt;*/
1503 func->function.disable = ffs_func_disable;
1504 func->function.setup = ffs_func_setup;
1505 func->function.suspend = ffs_func_suspend;
1506 func->function.resume = ffs_func_resume;
1507
1508 func->conf = c;
1509 func->gadget = cdev->gadget;
1510 func->ffs = ffs;
1511 ffs_data_get(ffs);
1512
1513 ret = usb_add_function(c, &func->function);
1514 if (unlikely(ret))
1515 ffs_func_free(func);
1516
1517 return ret;
1518}
1519
1520static void ffs_func_free(struct ffs_function *func)
1521{
1522 ENTER();
1523
1524 ffs_data_put(func->ffs);
1525
1526 kfree(func->eps);
1527 /* eps and interfaces_nums are allocated in the same chunk so
1528 * only one free is required. Descriptors are also allocated
1529 * in the same chunk. */
1530
1531 kfree(func);
1532}
1533
1534
1535static void ffs_func_eps_disable(struct ffs_function *func)
1536{
1537 struct ffs_ep *ep = func->eps;
1538 struct ffs_epfile *epfile = func->ffs->epfiles;
1539 unsigned count = func->ffs->eps_count;
1540 unsigned long flags;
1541
1542 spin_lock_irqsave(&func->ffs->eps_lock, flags);
1543 do {
1544 /* pending requests get nuked */
1545 if (likely(ep->ep))
1546 usb_ep_disable(ep->ep);
1547 epfile->ep = NULL;
1548
1549 ++ep;
1550 ++epfile;
1551 } while (--count);
1552 spin_unlock_irqrestore(&func->ffs->eps_lock, flags);
1553}
1554
1555static int ffs_func_eps_enable(struct ffs_function *func)
1556{
1557 struct ffs_data *ffs = func->ffs;
1558 struct ffs_ep *ep = func->eps;
1559 struct ffs_epfile *epfile = ffs->epfiles;
1560 unsigned count = ffs->eps_count;
1561 unsigned long flags;
1562 int ret = 0;
1563
1564 spin_lock_irqsave(&func->ffs->eps_lock, flags);
1565 do {
1566 struct usb_endpoint_descriptor *ds;
1567 ds = ep->descs[ep->descs[1] ? 1 : 0];
1568
1569 ep->ep->driver_data = ep;
1570 ret = usb_ep_enable(ep->ep, ds);
1571 if (likely(!ret)) {
1572 epfile->ep = ep;
1573 epfile->in = usb_endpoint_dir_in(ds);
1574 epfile->isoc = usb_endpoint_xfer_isoc(ds);
1575 } else {
1576 break;
1577 }
1578
1579 wake_up(&epfile->wait);
1580
1581 ++ep;
1582 ++epfile;
1583 } while (--count);
1584 spin_unlock_irqrestore(&func->ffs->eps_lock, flags);
1585
1586 return ret;
1587}
1588
1589
1590/* Parsing and building descriptors and strings *****************************/
1591
1592
1593/* This validates if data pointed by data is a valid USB descriptor as
1594 * well as record how many interfaces, endpoints and strings are
1595 * required by given configuration. Returns address afther the
1596 * descriptor or NULL if data is invalid. */
1597
1598enum ffs_entity_type {
1599 FFS_DESCRIPTOR, FFS_INTERFACE, FFS_STRING, FFS_ENDPOINT
1600};
1601
1602typedef int (*ffs_entity_callback)(enum ffs_entity_type entity,
1603 u8 *valuep,
1604 struct usb_descriptor_header *desc,
1605 void *priv);
1606
1607static int __must_check ffs_do_desc(char *data, unsigned len,
1608 ffs_entity_callback entity, void *priv)
1609{
1610 struct usb_descriptor_header *_ds = (void *)data;
1611 u8 length;
1612 int ret;
1613
1614 ENTER();
1615
1616 /* At least two bytes are required: length and type */
1617 if (len < 2) {
1618 FVDBG("descriptor too short");
1619 return -EINVAL;
1620 }
1621
1622 /* If we have at least as many bytes as the descriptor takes? */
1623 length = _ds->bLength;
1624 if (len < length) {
1625 FVDBG("descriptor longer then available data");
1626 return -EINVAL;
1627 }
1628
1629#define __entity_check_INTERFACE(val) 1
1630#define __entity_check_STRING(val) (val)
1631#define __entity_check_ENDPOINT(val) ((val) & USB_ENDPOINT_NUMBER_MASK)
1632#define __entity(type, val) do { \
1633 FVDBG("entity " #type "(%02x)", (val)); \
1634 if (unlikely(!__entity_check_ ##type(val))) { \
1635 FVDBG("invalid entity's value"); \
1636 return -EINVAL; \
1637 } \
1638 ret = entity(FFS_ ##type, &val, _ds, priv); \
1639 if (unlikely(ret < 0)) { \
1640 FDBG("entity " #type "(%02x); ret = %d", \
1641 (val), ret); \
1642 return ret; \
1643 } \
1644 } while (0)
1645
1646 /* Parse descriptor depending on type. */
1647 switch (_ds->bDescriptorType) {
1648 case USB_DT_DEVICE:
1649 case USB_DT_CONFIG:
1650 case USB_DT_STRING:
1651 case USB_DT_DEVICE_QUALIFIER:
1652 /* function can't have any of those */
1653 FVDBG("descriptor reserved for gadget: %d", _ds->bDescriptorType);
1654 return -EINVAL;
1655
1656 case USB_DT_INTERFACE: {
1657 struct usb_interface_descriptor *ds = (void *)_ds;
1658 FVDBG("interface descriptor");
1659 if (length != sizeof *ds)
1660 goto inv_length;
1661
1662 __entity(INTERFACE, ds->bInterfaceNumber);
1663 if (ds->iInterface)
1664 __entity(STRING, ds->iInterface);
1665 }
1666 break;
1667
1668 case USB_DT_ENDPOINT: {
1669 struct usb_endpoint_descriptor *ds = (void *)_ds;
1670 FVDBG("endpoint descriptor");
1671 if (length != USB_DT_ENDPOINT_SIZE &&
1672 length != USB_DT_ENDPOINT_AUDIO_SIZE)
1673 goto inv_length;
1674 __entity(ENDPOINT, ds->bEndpointAddress);
1675 }
1676 break;
1677
1678 case USB_DT_OTG:
1679 if (length != sizeof(struct usb_otg_descriptor))
1680 goto inv_length;
1681 break;
1682
1683 case USB_DT_INTERFACE_ASSOCIATION: {
1684 struct usb_interface_assoc_descriptor *ds = (void *)_ds;
1685 FVDBG("interface association descriptor");
1686 if (length != sizeof *ds)
1687 goto inv_length;
1688 if (ds->iFunction)
1689 __entity(STRING, ds->iFunction);
1690 }
1691 break;
1692
1693 case USB_DT_OTHER_SPEED_CONFIG:
1694 case USB_DT_INTERFACE_POWER:
1695 case USB_DT_DEBUG:
1696 case USB_DT_SECURITY:
1697 case USB_DT_CS_RADIO_CONTROL:
1698 /* TODO */
1699 FVDBG("unimplemented descriptor: %d", _ds->bDescriptorType);
1700 return -EINVAL;
1701
1702 default:
1703 /* We should never be here */
1704 FVDBG("unknown descriptor: %d", _ds->bDescriptorType);
1705 return -EINVAL;
1706
1707 inv_length:
1708 FVDBG("invalid length: %d (descriptor %d)",
1709 _ds->bLength, _ds->bDescriptorType);
1710 return -EINVAL;
1711 }
1712
1713#undef __entity
1714#undef __entity_check_DESCRIPTOR
1715#undef __entity_check_INTERFACE
1716#undef __entity_check_STRING
1717#undef __entity_check_ENDPOINT
1718
1719 return length;
1720}
1721
1722
1723static int __must_check ffs_do_descs(unsigned count, char *data, unsigned len,
1724 ffs_entity_callback entity, void *priv)
1725{
1726 const unsigned _len = len;
1727 unsigned long num = 0;
1728
1729 ENTER();
1730
1731 for (;;) {
1732 int ret;
1733
1734 if (num == count)
1735 data = NULL;
1736
1737 /* Record "descriptor" entitny */
1738 ret = entity(FFS_DESCRIPTOR, (u8 *)num, (void *)data, priv);
1739 if (unlikely(ret < 0)) {
1740 FDBG("entity DESCRIPTOR(%02lx); ret = %d", num, ret);
1741 return ret;
1742 }
1743
1744 if (!data)
1745 return _len - len;
1746
1747 ret = ffs_do_desc(data, len, entity, priv);
1748 if (unlikely(ret < 0)) {
1749 FDBG("%s returns %d", __func__, ret);
1750 return ret;
1751 }
1752
1753 len -= ret;
1754 data += ret;
1755 ++num;
1756 }
1757}
1758
1759
1760static int __ffs_data_do_entity(enum ffs_entity_type type,
1761 u8 *valuep, struct usb_descriptor_header *desc,
1762 void *priv)
1763{
1764 struct ffs_data *ffs = priv;
1765
1766 ENTER();
1767
1768 switch (type) {
1769 case FFS_DESCRIPTOR:
1770 break;
1771
1772 case FFS_INTERFACE:
1773 /* Interfaces are indexed from zero so if we
1774 * encountered interface "n" then there are at least
1775 * "n+1" interfaces. */
1776 if (*valuep >= ffs->interfaces_count)
1777 ffs->interfaces_count = *valuep + 1;
1778 break;
1779
1780 case FFS_STRING:
1781 /* Strings are indexed from 1 (0 is magic ;) reserved
1782 * for languages list or some such) */
1783 if (*valuep > ffs->strings_count)
1784 ffs->strings_count = *valuep;
1785 break;
1786
1787 case FFS_ENDPOINT:
1788 /* Endpoints are indexed from 1 as well. */
1789 if ((*valuep & USB_ENDPOINT_NUMBER_MASK) > ffs->eps_count)
1790 ffs->eps_count = (*valuep & USB_ENDPOINT_NUMBER_MASK);
1791 break;
1792 }
1793
1794 return 0;
1795}
1796
1797
1798static int __ffs_data_got_descs(struct ffs_data *ffs,
1799 char *const _data, size_t len)
1800{
1801 unsigned fs_count, hs_count;
1802 int fs_len, ret = -EINVAL;
1803 char *data = _data;
1804
1805 ENTER();
1806
1807 if (unlikely(get_unaligned_le32(data) != FUNCTIONFS_DESCRIPTORS_MAGIC ||
1808 get_unaligned_le32(data + 4) != len))
1809 goto error;
1810 fs_count = get_unaligned_le32(data + 8);
1811 hs_count = get_unaligned_le32(data + 12);
1812
1813 if (!fs_count && !hs_count)
1814 goto einval;
1815
1816 data += 16;
1817 len -= 16;
1818
1819 if (likely(fs_count)) {
1820 fs_len = ffs_do_descs(fs_count, data, len,
1821 __ffs_data_do_entity, ffs);
1822 if (unlikely(fs_len < 0)) {
1823 ret = fs_len;
1824 goto error;
1825 }
1826
1827 data += fs_len;
1828 len -= fs_len;
1829 } else {
1830 fs_len = 0;
1831 }
1832
1833 if (likely(hs_count)) {
1834 ret = ffs_do_descs(hs_count, data, len,
1835 __ffs_data_do_entity, ffs);
1836 if (unlikely(ret < 0))
1837 goto error;
1838 } else {
1839 ret = 0;
1840 }
1841
1842 if (unlikely(len != ret))
1843 goto einval;
1844
1845 ffs->raw_fs_descs_length = fs_len;
1846 ffs->raw_descs_length = fs_len + ret;
1847 ffs->raw_descs = _data;
1848 ffs->fs_descs_count = fs_count;
1849 ffs->hs_descs_count = hs_count;
1850
1851 return 0;
1852
1853einval:
1854 ret = -EINVAL;
1855error:
1856 kfree(_data);
1857 return ret;
1858}
1859
1860
1861
1862static int __ffs_data_got_strings(struct ffs_data *ffs,
1863 char *const _data, size_t len)
1864{
1865 u32 str_count, needed_count, lang_count;
1866 struct usb_gadget_strings **stringtabs, *t;
1867 struct usb_string *strings, *s;
1868 const char *data = _data;
1869
1870 ENTER();
1871
1872 if (unlikely(get_unaligned_le32(data) != FUNCTIONFS_STRINGS_MAGIC ||
1873 get_unaligned_le32(data + 4) != len))
1874 goto error;
1875 str_count = get_unaligned_le32(data + 8);
1876 lang_count = get_unaligned_le32(data + 12);
1877
1878 /* if one is zero the other must be zero */
1879 if (unlikely(!str_count != !lang_count))
1880 goto error;
1881
1882 /* Do we have at least as many strings as descriptors need? */
1883 needed_count = ffs->strings_count;
1884 if (unlikely(str_count < needed_count))
1885 goto error;
1886
1887 /* If we don't need any strings just return and free all
1888 * memory */
1889 if (!needed_count) {
1890 kfree(_data);
1891 return 0;
1892 }
1893
1894 /* Allocate */
1895 {
1896 /* Allocate everything in one chunk so there's less
1897 * maintanance. */
1898 struct {
1899 struct usb_gadget_strings *stringtabs[lang_count + 1];
1900 struct usb_gadget_strings stringtab[lang_count];
1901 struct usb_string strings[lang_count*(needed_count+1)];
1902 } *d;
1903 unsigned i = 0;
1904
1905 d = kmalloc(sizeof *d, GFP_KERNEL);
1906 if (unlikely(!d)) {
1907 kfree(_data);
1908 return -ENOMEM;
1909 }
1910
1911 stringtabs = d->stringtabs;
1912 t = d->stringtab;
1913 i = lang_count;
1914 do {
1915 *stringtabs++ = t++;
1916 } while (--i);
1917 *stringtabs = NULL;
1918
1919 stringtabs = d->stringtabs;
1920 t = d->stringtab;
1921 s = d->strings;
1922 strings = s;
1923 }
1924
1925 /* For each language */
1926 data += 16;
1927 len -= 16;
1928
1929 do { /* lang_count > 0 so we can use do-while */
1930 unsigned needed = needed_count;
1931
1932 if (unlikely(len < 3))
1933 goto error_free;
1934 t->language = get_unaligned_le16(data);
1935 t->strings = s;
1936 ++t;
1937
1938 data += 2;
1939 len -= 2;
1940
1941 /* For each string */
1942 do { /* str_count > 0 so we can use do-while */
1943 size_t length = strnlen(data, len);
1944
1945 if (unlikely(length == len))
1946 goto error_free;
1947
1948 /* user may provide more strings then we need,
1949 * if that's the case we simply ingore the
1950 * rest */
1951 if (likely(needed)) {
1952 /* s->id will be set while adding
1953 * function to configuration so for
1954 * now just leave garbage here. */
1955 s->s = data;
1956 --needed;
1957 ++s;
1958 }
1959
1960 data += length + 1;
1961 len -= length + 1;
1962 } while (--str_count);
1963
1964 s->id = 0; /* terminator */
1965 s->s = NULL;
1966 ++s;
1967
1968 } while (--lang_count);
1969
1970 /* Some garbage left? */
1971 if (unlikely(len))
1972 goto error_free;
1973
1974 /* Done! */
1975 ffs->stringtabs = stringtabs;
1976 ffs->raw_strings = _data;
1977
1978 return 0;
1979
1980error_free:
1981 kfree(stringtabs);
1982error:
1983 kfree(_data);
1984 return -EINVAL;
1985}
1986
1987
1988
1989
1990/* Events handling and management *******************************************/
1991
1992static void __ffs_event_add(struct ffs_data *ffs,
1993 enum usb_functionfs_event_type type)
1994{
1995 enum usb_functionfs_event_type rem_type1, rem_type2 = type;
1996 int neg = 0;
1997
1998 /* Abort any unhandled setup */
1999 /* We do not need to worry about some cmpxchg() changing value
2000 * of ffs->setup_state without holding the lock because when
2001 * state is FFS_SETUP_PENDING cmpxchg() in several places in
2002 * the source does nothing. */
2003 if (ffs->setup_state == FFS_SETUP_PENDING)
2004 ffs->setup_state = FFS_SETUP_CANCELED;
2005
2006 switch (type) {
2007 case FUNCTIONFS_RESUME:
2008 rem_type2 = FUNCTIONFS_SUSPEND;
2009 /* FALL THGOUTH */
2010 case FUNCTIONFS_SUSPEND:
2011 case FUNCTIONFS_SETUP:
2012 rem_type1 = type;
2013 /* discard all similar events */
2014 break;
2015
2016 case FUNCTIONFS_BIND:
2017 case FUNCTIONFS_UNBIND:
2018 case FUNCTIONFS_DISABLE:
2019 case FUNCTIONFS_ENABLE:
2020 /* discard everything other then power management. */
2021 rem_type1 = FUNCTIONFS_SUSPEND;
2022 rem_type2 = FUNCTIONFS_RESUME;
2023 neg = 1;
2024 break;
2025
2026 default:
2027 BUG();
2028 }
2029
2030 {
2031 u8 *ev = ffs->ev.types, *out = ev;
2032 unsigned n = ffs->ev.count;
2033 for (; n; --n, ++ev)
2034 if ((*ev == rem_type1 || *ev == rem_type2) == neg)
2035 *out++ = *ev;
2036 else
2037 FVDBG("purging event %d", *ev);
2038 ffs->ev.count = out - ffs->ev.types;
2039 }
2040
2041 FVDBG("adding event %d", type);
2042 ffs->ev.types[ffs->ev.count++] = type;
2043 wake_up_locked(&ffs->ev.waitq);
2044}
2045
2046static void ffs_event_add(struct ffs_data *ffs,
2047 enum usb_functionfs_event_type type)
2048{
2049 unsigned long flags;
2050 spin_lock_irqsave(&ffs->ev.waitq.lock, flags);
2051 __ffs_event_add(ffs, type);
2052 spin_unlock_irqrestore(&ffs->ev.waitq.lock, flags);
2053}
2054
2055
2056/* Bind/unbind USB function hooks *******************************************/
2057
2058static int __ffs_func_bind_do_descs(enum ffs_entity_type type, u8 *valuep,
2059 struct usb_descriptor_header *desc,
2060 void *priv)
2061{
2062 struct usb_endpoint_descriptor *ds = (void *)desc;
2063 struct ffs_function *func = priv;
2064 struct ffs_ep *ffs_ep;
2065
2066 /* If hs_descriptors is not NULL then we are reading hs
2067 * descriptors now */
2068 const int isHS = func->function.hs_descriptors != NULL;
2069 unsigned idx;
2070
2071 if (type != FFS_DESCRIPTOR)
2072 return 0;
2073
2074 if (isHS)
2075 func->function.hs_descriptors[(long)valuep] = desc;
2076 else
2077 func->function.descriptors[(long)valuep] = desc;
2078
2079 if (!desc || desc->bDescriptorType != USB_DT_ENDPOINT)
2080 return 0;
2081
2082 idx = (ds->bEndpointAddress & USB_ENDPOINT_NUMBER_MASK) - 1;
2083 ffs_ep = func->eps + idx;
2084
2085 if (unlikely(ffs_ep->descs[isHS])) {
2086 FVDBG("two %sspeed descriptors for EP %d",
2087 isHS ? "high" : "full",
2088 ds->bEndpointAddress & USB_ENDPOINT_NUMBER_MASK);
2089 return -EINVAL;
2090 }
2091 ffs_ep->descs[isHS] = ds;
2092
2093 ffs_dump_mem(": Original ep desc", ds, ds->bLength);
2094 if (ffs_ep->ep) {
2095 ds->bEndpointAddress = ffs_ep->descs[0]->bEndpointAddress;
2096 if (!ds->wMaxPacketSize)
2097 ds->wMaxPacketSize = ffs_ep->descs[0]->wMaxPacketSize;
2098 } else {
2099 struct usb_request *req;
2100 struct usb_ep *ep;
2101
2102 FVDBG("autoconfig");
2103 ep = usb_ep_autoconfig(func->gadget, ds);
2104 if (unlikely(!ep))
2105 return -ENOTSUPP;
2106 ep->driver_data = func->eps + idx;;
2107
2108 req = usb_ep_alloc_request(ep, GFP_KERNEL);
2109 if (unlikely(!req))
2110 return -ENOMEM;
2111
2112 ffs_ep->ep = ep;
2113 ffs_ep->req = req;
2114 func->eps_revmap[ds->bEndpointAddress &
2115 USB_ENDPOINT_NUMBER_MASK] = idx + 1;
2116 }
2117 ffs_dump_mem(": Rewritten ep desc", ds, ds->bLength);
2118
2119 return 0;
2120}
2121
2122
2123static int __ffs_func_bind_do_nums(enum ffs_entity_type type, u8 *valuep,
2124 struct usb_descriptor_header *desc,
2125 void *priv)
2126{
2127 struct ffs_function *func = priv;
2128 unsigned idx;
2129 u8 newValue;
2130
2131 switch (type) {
2132 default:
2133 case FFS_DESCRIPTOR:
2134 /* Handled in previous pass by __ffs_func_bind_do_descs() */
2135 return 0;
2136
2137 case FFS_INTERFACE:
2138 idx = *valuep;
2139 if (func->interfaces_nums[idx] < 0) {
2140 int id = usb_interface_id(func->conf, &func->function);
2141 if (unlikely(id < 0))
2142 return id;
2143 func->interfaces_nums[idx] = id;
2144 }
2145 newValue = func->interfaces_nums[idx];
2146 break;
2147
2148 case FFS_STRING:
2149 /* String' IDs are allocated when fsf_data is bound to cdev */
2150 newValue = func->ffs->stringtabs[0]->strings[*valuep - 1].id;
2151 break;
2152
2153 case FFS_ENDPOINT:
2154 /* USB_DT_ENDPOINT are handled in
2155 * __ffs_func_bind_do_descs(). */
2156 if (desc->bDescriptorType == USB_DT_ENDPOINT)
2157 return 0;
2158
2159 idx = (*valuep & USB_ENDPOINT_NUMBER_MASK) - 1;
2160 if (unlikely(!func->eps[idx].ep))
2161 return -EINVAL;
2162
2163 {
2164 struct usb_endpoint_descriptor **descs;
2165 descs = func->eps[idx].descs;
2166 newValue = descs[descs[0] ? 0 : 1]->bEndpointAddress;
2167 }
2168 break;
2169 }
2170
2171 FVDBG("%02x -> %02x", *valuep, newValue);
2172 *valuep = newValue;
2173 return 0;
2174}
2175
2176static int ffs_func_bind(struct usb_configuration *c,
2177 struct usb_function *f)
2178{
2179 struct ffs_function *func = ffs_func_from_usb(f);
2180 struct ffs_data *ffs = func->ffs;
2181
2182 const int full = !!func->ffs->fs_descs_count;
2183 const int high = gadget_is_dualspeed(func->gadget) &&
2184 func->ffs->hs_descs_count;
2185
2186 int ret;
2187
2188 /* Make it a single chunk, less management later on */
2189 struct {
2190 struct ffs_ep eps[ffs->eps_count];
2191 struct usb_descriptor_header
2192 *fs_descs[full ? ffs->fs_descs_count + 1 : 0];
2193 struct usb_descriptor_header
2194 *hs_descs[high ? ffs->hs_descs_count + 1 : 0];
2195 short inums[ffs->interfaces_count];
2196 char raw_descs[high ? ffs->raw_descs_length
2197 : ffs->raw_fs_descs_length];
2198 } *data;
2199
2200 ENTER();
2201
2202 /* Only high speed but not supported by gadget? */
2203 if (unlikely(!(full | high)))
2204 return -ENOTSUPP;
2205
2206 /* Allocate */
2207 data = kmalloc(sizeof *data, GFP_KERNEL);
2208 if (unlikely(!data))
2209 return -ENOMEM;
2210
2211 /* Zero */
2212 memset(data->eps, 0, sizeof data->eps);
2213 memcpy(data->raw_descs, ffs->raw_descs + 16, sizeof data->raw_descs);
2214 memset(data->inums, 0xff, sizeof data->inums);
2215 for (ret = ffs->eps_count; ret; --ret)
2216 data->eps[ret].num = -1;
2217
2218 /* Save pointers */
2219 func->eps = data->eps;
2220 func->interfaces_nums = data->inums;
2221
2222 /* Go throught all the endpoint descriptors and allocate
2223 * endpoints first, so that later we can rewrite the endpoint
2224 * numbers without worying that it may be described later on. */
2225 if (likely(full)) {
2226 func->function.descriptors = data->fs_descs;
2227 ret = ffs_do_descs(ffs->fs_descs_count,
2228 data->raw_descs,
2229 sizeof data->raw_descs,
2230 __ffs_func_bind_do_descs, func);
2231 if (unlikely(ret < 0))
2232 goto error;
2233 } else {
2234 ret = 0;
2235 }
2236
2237 if (likely(high)) {
2238 func->function.hs_descriptors = data->hs_descs;
2239 ret = ffs_do_descs(ffs->hs_descs_count,
2240 data->raw_descs + ret,
2241 (sizeof data->raw_descs) - ret,
2242 __ffs_func_bind_do_descs, func);
2243 }
2244
2245 /* Now handle interface numbers allocation and interface and
2246 * enpoint numbers rewritting. We can do that in one go
2247 * now. */
2248 ret = ffs_do_descs(ffs->fs_descs_count +
2249 (high ? ffs->hs_descs_count : 0),
2250 data->raw_descs, sizeof data->raw_descs,
2251 __ffs_func_bind_do_nums, func);
2252 if (unlikely(ret < 0))
2253 goto error;
2254
2255 /* And we're done */
2256 ffs_event_add(ffs, FUNCTIONFS_BIND);
2257 return 0;
2258
2259error:
2260 /* XXX Do we need to release all claimed endpoints here? */
2261 return ret;
2262}
2263
2264
2265/* Other USB function hooks *************************************************/
2266
2267static void ffs_func_unbind(struct usb_configuration *c,
2268 struct usb_function *f)
2269{
2270 struct ffs_function *func = ffs_func_from_usb(f);
2271 struct ffs_data *ffs = func->ffs;
2272
2273 ENTER();
2274
2275 if (ffs->func == func) {
2276 ffs_func_eps_disable(func);
2277 ffs->func = NULL;
2278 }
2279
2280 ffs_event_add(ffs, FUNCTIONFS_UNBIND);
2281
2282 ffs_func_free(func);
2283}
2284
2285
2286static int ffs_func_set_alt(struct usb_function *f,
2287 unsigned interface, unsigned alt)
2288{
2289 struct ffs_function *func = ffs_func_from_usb(f);
2290 struct ffs_data *ffs = func->ffs;
2291 int ret = 0, intf;
2292
2293 if (alt != (unsigned)-1) {
2294 intf = ffs_func_revmap_intf(func, interface);
2295 if (unlikely(intf < 0))
2296 return intf;
2297 }
2298
2299 if (ffs->func)
2300 ffs_func_eps_disable(ffs->func);
2301
2302 if (ffs->state != FFS_ACTIVE)
2303 return -ENODEV;
2304
2305 if (alt == (unsigned)-1) {
2306 ffs->func = NULL;
2307 ffs_event_add(ffs, FUNCTIONFS_DISABLE);
2308 return 0;
2309 }
2310
2311 ffs->func = func;
2312 ret = ffs_func_eps_enable(func);
2313 if (likely(ret >= 0))
2314 ffs_event_add(ffs, FUNCTIONFS_ENABLE);
2315 return ret;
2316}
2317
2318static void ffs_func_disable(struct usb_function *f)
2319{
2320 ffs_func_set_alt(f, 0, (unsigned)-1);
2321}
2322
2323static int ffs_func_setup(struct usb_function *f,
2324 const struct usb_ctrlrequest *creq)
2325{
2326 struct ffs_function *func = ffs_func_from_usb(f);
2327 struct ffs_data *ffs = func->ffs;
2328 unsigned long flags;
2329 int ret;
2330
2331 ENTER();
2332
2333 FVDBG("creq->bRequestType = %02x", creq->bRequestType);
2334 FVDBG("creq->bRequest = %02x", creq->bRequest);
2335 FVDBG("creq->wValue = %04x", le16_to_cpu(creq->wValue));
2336 FVDBG("creq->wIndex = %04x", le16_to_cpu(creq->wIndex));
2337 FVDBG("creq->wLength = %04x", le16_to_cpu(creq->wLength));
2338
2339 /* Most requests directed to interface go throught here
2340 * (notable exceptions are set/get interface) so we need to
2341 * handle them. All other either handled by composite or
2342 * passed to usb_configuration->setup() (if one is set). No
2343 * matter, we will handle requests directed to endpoint here
2344 * as well (as it's straightforward) but what to do with any
2345 * other request? */
2346
2347 if (ffs->state != FFS_ACTIVE)
2348 return -ENODEV;
2349
2350 switch (creq->bRequestType & USB_RECIP_MASK) {
2351 case USB_RECIP_INTERFACE:
2352 ret = ffs_func_revmap_intf(func, le16_to_cpu(creq->wIndex));
2353 if (unlikely(ret < 0))
2354 return ret;
2355 break;
2356
2357 case USB_RECIP_ENDPOINT:
2358 ret = ffs_func_revmap_ep(func, le16_to_cpu(creq->wIndex));
2359 if (unlikely(ret < 0))
2360 return ret;
2361 break;
2362
2363 default:
2364 return -EOPNOTSUPP;
2365 }
2366
2367 spin_lock_irqsave(&ffs->ev.waitq.lock, flags);
2368 ffs->ev.setup = *creq;
2369 ffs->ev.setup.wIndex = cpu_to_le16(ret);
2370 __ffs_event_add(ffs, FUNCTIONFS_SETUP);
2371 spin_unlock_irqrestore(&ffs->ev.waitq.lock, flags);
2372
2373 return 0;
2374}
2375
2376static void ffs_func_suspend(struct usb_function *f)
2377{
2378 ENTER();
2379 ffs_event_add(ffs_func_from_usb(f)->ffs, FUNCTIONFS_SUSPEND);
2380}
2381
2382static void ffs_func_resume(struct usb_function *f)
2383{
2384 ENTER();
2385 ffs_event_add(ffs_func_from_usb(f)->ffs, FUNCTIONFS_RESUME);
2386}
2387
2388
2389
2390/* Enpoint and interface numbers reverse mapping ****************************/
2391
2392static int ffs_func_revmap_ep(struct ffs_function *func, u8 num)
2393{
2394 num = func->eps_revmap[num & USB_ENDPOINT_NUMBER_MASK];
2395 return num ? num : -EDOM;
2396}
2397
2398static int ffs_func_revmap_intf(struct ffs_function *func, u8 intf)
2399{
2400 short *nums = func->interfaces_nums;
2401 unsigned count = func->ffs->interfaces_count;
2402
2403 for (; count; --count, ++nums) {
2404 if (*nums >= 0 && *nums == intf)
2405 return nums - func->interfaces_nums;
2406 }
2407
2408 return -EDOM;
2409}
2410
2411
2412/* Misc helper functions ****************************************************/
2413
2414static int ffs_mutex_lock(struct mutex *mutex, unsigned nonblock)
2415{
2416 return nonblock
2417 ? likely(mutex_trylock(mutex)) ? 0 : -EAGAIN
2418 : mutex_lock_interruptible(mutex);
2419}
2420
2421
2422static char *ffs_prepare_buffer(const char * __user buf, size_t len)
2423{
2424 char *data;
2425
2426 if (unlikely(!len))
2427 return NULL;
2428
2429 data = kmalloc(len, GFP_KERNEL);
2430 if (unlikely(!data))
2431 return ERR_PTR(-ENOMEM);
2432
2433 if (unlikely(__copy_from_user(data, buf, len))) {
2434 kfree(data);
2435 return ERR_PTR(-EFAULT);
2436 }
2437
2438 FVDBG("Buffer from user space:");
2439 ffs_dump_mem("", data, len);
2440
2441 return data;
2442}