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-rw-r--r--drivers/usb/gadget/f_fs.c2441
-rw-r--r--include/linux/usb/functionfs.h199
2 files changed, 2640 insertions, 0 deletions
diff --git a/drivers/usb/gadget/f_fs.c b/drivers/usb/gadget/f_fs.c
new file mode 100644
index 000000000000..af89ca672c60
--- /dev/null
+++ b/drivers/usb/gadget/f_fs.c
@@ -0,0 +1,2441 @@
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>
31#include <asm/unaligned.h>
32#include <linux/smp_lock.h>
33
34#include <linux/usb/composite.h>
35#include <linux/usb/functionfs.h>
36
37
38#define FUNCTIONFS_MAGIC 0xa647361 /* Chosen by a honest dice roll ;) */
39
40
41/* Debuging *****************************************************************/
42
43#define ffs_printk(level, fmt, args...) printk(level "f_fs: " fmt "\n", ## args)
44
45#define FERR(...) ffs_printk(KERN_ERR, __VA_ARGS__)
46#define FINFO(...) ffs_printk(KERN_INFO, __VA_ARGS__)
47
48#ifdef DEBUG
49# define FDBG(...) ffs_printk(KERN_DEBUG, __VA_ARGS__)
50#else
51# define FDBG(...) do { } while (0)
52#endif /* DEBUG */
53
54#ifdef VERBOSE_DEBUG
55# define FVDBG FDBG
56#else
57# define FVDBG(...) do { } while (0)
58#endif /* VERBOSE_DEBUG */
59
60#define ENTER() FVDBG("%s()", __func__)
61
62#ifdef VERBOSE_DEBUG
63# define ffs_dump_mem(prefix, ptr, len) \
64 print_hex_dump_bytes("f_fs" prefix ": ", DUMP_PREFIX_NONE, ptr, len)
65#else
66# define ffs_dump_mem(prefix, ptr, len) do { } while (0)
67#endif
68
69
70/* The data structure and setup file ****************************************/
71
72enum ffs_state {
73 /* Waiting for descriptors and strings. */
74 /* In this state no open(2), read(2) or write(2) on epfiles
75 * may succeed (which should not be the problem as there
76 * should be no such files opened in the firts place). */
77 FFS_READ_DESCRIPTORS,
78 FFS_READ_STRINGS,
79
80 /* We've got descriptors and strings. We are or have called
81 * functionfs_ready_callback(). functionfs_bind() may have
82 * been called but we don't know. */
83 /* This is the only state in which operations on epfiles may
84 * succeed. */
85 FFS_ACTIVE,
86
87 /* All endpoints have been closed. This state is also set if
88 * we encounter an unrecoverable error. The only
89 * unrecoverable error is situation when after reading strings
90 * from user space we fail to initialise EP files or
91 * functionfs_ready_callback() returns with error (<0). */
92 /* In this state no open(2), read(2) or write(2) (both on ep0
93 * as well as epfile) may succeed (at this point epfiles are
94 * unlinked and all closed so this is not a problem; ep0 is
95 * also closed but ep0 file exists and so open(2) on ep0 must
96 * fail). */
97 FFS_CLOSING
98};
99
100
101enum ffs_setup_state {
102 /* There is no setup request pending. */
103 FFS_NO_SETUP,
104 /* User has read events and there was a setup request event
105 * there. The next read/write on ep0 will handle the
106 * request. */
107 FFS_SETUP_PENDING,
108 /* There was event pending but before user space handled it
109 * some other event was introduced which canceled existing
110 * setup. If this state is set read/write on ep0 return
111 * -EIDRM. This state is only set when adding event. */
112 FFS_SETUP_CANCELED
113};
114
115
116
117struct ffs_epfile;
118struct ffs_function;
119
120struct ffs_data {
121 struct usb_gadget *gadget;
122
123 /* Protect access read/write operations, only one read/write
124 * at a time. As a consequence protects ep0req and company.
125 * While setup request is being processed (queued) this is
126 * held. */
127 struct mutex mutex;
128
129 /* Protect access to enpoint related structures (basically
130 * usb_ep_queue(), usb_ep_dequeue(), etc. calls) except for
131 * endpint zero. */
132 spinlock_t eps_lock;
133
134 /* XXX REVISIT do we need our own request? Since we are not
135 * handling setup requests immidiatelly 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 taht the case? Or maybe we can use cdev->req
139 * after all, maybe we just need some spinlock for that? */
140 struct usb_request *ep0req; /* P: mutex */
141 struct completion ep0req_completion; /* P: mutex */
142 int ep0req_status; /* P: mutex */
143
144 /* reference counter */
145 atomic_t ref;
146 /* how many files are opened (EP0 and others) */
147 atomic_t opened;
148
149 /* EP0 state */
150 enum ffs_state state;
151
152 /*
153 * Possible transations:
154 * + FFS_NO_SETUP -> FFS_SETUP_PENDING -- P: ev.waitq.lock
155 * happens only in ep0 read which is P: mutex
156 * + FFS_SETUP_PENDING -> FFS_NO_SETUP -- P: ev.waitq.lock
157 * happens only in ep0 i/o which is P: mutex
158 * + FFS_SETUP_PENDING -> FFS_SETUP_CANCELED -- P: ev.waitq.lock
159 * + FFS_SETUP_CANCELED -> FFS_NO_SETUP -- cmpxchg
160 */
161 enum ffs_setup_state setup_state;
162
163#define FFS_SETUP_STATE(ffs) \
164 ((enum ffs_setup_state)cmpxchg(&(ffs)->setup_state, \
165 FFS_SETUP_CANCELED, FFS_NO_SETUP))
166
167 /* Events & such. */
168 struct {
169 u8 types[4];
170 unsigned short count;
171 /* XXX REVISIT need to update it in some places, or do we? */
172 unsigned short can_stall;
173 struct usb_ctrlrequest setup;
174
175 wait_queue_head_t waitq;
176 } ev; /* the whole structure, P: ev.waitq.lock */
177
178 /* Flags */
179 unsigned long flags;
180#define FFS_FL_CALL_CLOSED_CALLBACK 0
181#define FFS_FL_BOUND 1
182
183 /* Active function */
184 struct ffs_function *func;
185
186 /* Device name, write once when file system is mounted.
187 * Intendet for user to read if she wants. */
188 const char *dev_name;
189 /* Private data for our user (ie. gadget). Managed by
190 * user. */
191 void *private_data;
192
193 /* filled by __ffs_data_got_descs() */
194 /* real descriptors are 16 bytes after raw_descs (so you need
195 * to skip 16 bytes (ie. ffs->raw_descs + 16) to get to the
196 * first full speed descriptor). raw_descs_length and
197 * raw_fs_descs_length do not have those 16 bytes added. */
198 const void *raw_descs;
199 unsigned raw_descs_length;
200 unsigned raw_fs_descs_length;
201 unsigned fs_descs_count;
202 unsigned hs_descs_count;
203
204 unsigned short strings_count;
205 unsigned short interfaces_count;
206 unsigned short eps_count;
207 unsigned short _pad1;
208
209 /* filled by __ffs_data_got_strings() */
210 /* ids in stringtabs are set in functionfs_bind() */
211 const void *raw_strings;
212 struct usb_gadget_strings **stringtabs;
213
214 /* File system's super block, write once when file system is mounted. */
215 struct super_block *sb;
216
217 /* File permissions, written once when fs is mounted*/
218 struct ffs_file_perms {
219 umode_t mode;
220 uid_t uid;
221 gid_t gid;
222 } file_perms;
223
224 /* The endpoint files, filled by ffs_epfiles_create(),
225 * destroyed by ffs_epfiles_destroy(). */
226 struct ffs_epfile *epfiles;
227};
228
229/* Reference counter handling */
230static void ffs_data_get(struct ffs_data *ffs);
231static void ffs_data_put(struct ffs_data *ffs);
232/* Creates new ffs_data object. */
233static struct ffs_data *__must_check ffs_data_new(void) __attribute__((malloc));
234
235/* Opened counter handling. */
236static void ffs_data_opened(struct ffs_data *ffs);
237static void ffs_data_closed(struct ffs_data *ffs);
238
239/* Called with ffs->mutex held; take over ownerrship of data. */
240static int __must_check
241__ffs_data_got_descs(struct ffs_data *ffs, char *data, size_t len);
242static int __must_check
243__ffs_data_got_strings(struct ffs_data *ffs, char *data, size_t len);
244
245
246/* The function structure ***************************************************/
247
248struct ffs_ep;
249
250struct ffs_function {
251 struct usb_configuration *conf;
252 struct usb_gadget *gadget;
253 struct ffs_data *ffs;
254
255 struct ffs_ep *eps;
256 u8 eps_revmap[16];
257 short *interfaces_nums;
258
259 struct usb_function function;
260};
261
262
263static struct ffs_function *ffs_func_from_usb(struct usb_function *f)
264{
265 return container_of(f, struct ffs_function, function);
266}
267
268static void ffs_func_free(struct ffs_function *func);
269
270
271static void ffs_func_eps_disable(struct ffs_function *func);
272static int __must_check ffs_func_eps_enable(struct ffs_function *func);
273
274
275static int ffs_func_bind(struct usb_configuration *,
276 struct usb_function *);
277static void ffs_func_unbind(struct usb_configuration *,
278 struct usb_function *);
279static int ffs_func_set_alt(struct usb_function *, unsigned, unsigned);
280static void ffs_func_disable(struct usb_function *);
281static int ffs_func_setup(struct usb_function *,
282 const struct usb_ctrlrequest *);
283static void ffs_func_suspend(struct usb_function *);
284static void ffs_func_resume(struct usb_function *);
285
286
287static int ffs_func_revmap_ep(struct ffs_function *func, u8 num);
288static int ffs_func_revmap_intf(struct ffs_function *func, u8 intf);
289
290
291
292/* The endpoints structures *************************************************/
293
294struct ffs_ep {
295 struct usb_ep *ep; /* P: ffs->eps_lock */
296 struct usb_request *req; /* P: epfile->mutex */
297
298 /* [0]: full speed, [1]: high speed */
299 struct usb_endpoint_descriptor *descs[2];
300
301 u8 num;
302
303 int status; /* P: epfile->mutex */
304};
305
306struct ffs_epfile {
307 /* Protects ep->ep and ep->req. */
308 struct mutex mutex;
309 wait_queue_head_t wait;
310
311 struct ffs_data *ffs;
312 struct ffs_ep *ep; /* P: ffs->eps_lock */
313
314 struct dentry *dentry;
315
316 char name[5];
317
318 unsigned char in; /* P: ffs->eps_lock */
319 unsigned char isoc; /* P: ffs->eps_lock */
320
321 unsigned char _pad;
322};
323
324
325static int __must_check ffs_epfiles_create(struct ffs_data *ffs);
326static void ffs_epfiles_destroy(struct ffs_epfile *epfiles, unsigned count);
327
328static struct inode *__must_check
329ffs_sb_create_file(struct super_block *sb, const char *name, void *data,
330 const struct file_operations *fops,
331 struct dentry **dentry_p);
332
333
334/* Misc helper functions ****************************************************/
335
336static int ffs_mutex_lock(struct mutex *mutex, unsigned nonblock)
337 __attribute__((warn_unused_result, nonnull));
338static char *ffs_prepare_buffer(const char * __user buf, size_t len)
339 __attribute__((warn_unused_result, nonnull));
340
341
342/* Control file aka ep0 *****************************************************/
343
344static void ffs_ep0_complete(struct usb_ep *ep, struct usb_request *req)
345{
346 struct ffs_data *ffs = req->context;
347
348 complete_all(&ffs->ep0req_completion);
349}
350
351
352static int __ffs_ep0_queue_wait(struct ffs_data *ffs, char *data, size_t len)
353{
354 struct usb_request *req = ffs->ep0req;
355 int ret;
356
357 req->zero = len < le16_to_cpu(ffs->ev.setup.wLength);
358
359 spin_unlock_irq(&ffs->ev.waitq.lock);
360
361 req->buf = data;
362 req->length = len;
363
364 INIT_COMPLETION(ffs->ep0req_completion);
365
366 ret = usb_ep_queue(ffs->gadget->ep0, req, GFP_ATOMIC);
367 if (unlikely(ret < 0))
368 return ret;
369
370 ret = wait_for_completion_interruptible(&ffs->ep0req_completion);
371 if (unlikely(ret)) {
372 usb_ep_dequeue(ffs->gadget->ep0, req);
373 return -EINTR;
374 }
375
376 ffs->setup_state = FFS_NO_SETUP;
377 return ffs->ep0req_status;
378}
379
380static int __ffs_ep0_stall(struct ffs_data *ffs)
381{
382 if (ffs->ev.can_stall) {
383 FVDBG("ep0 stall\n");
384 usb_ep_set_halt(ffs->gadget->ep0);
385 ffs->setup_state = FFS_NO_SETUP;
386 return -EL2HLT;
387 } else {
388 FDBG("bogus ep0 stall!\n");
389 return -ESRCH;
390 }
391}
392
393
394static ssize_t ffs_ep0_write(struct file *file, const char __user *buf,
395 size_t len, loff_t *ptr)
396{
397 struct ffs_data *ffs = file->private_data;
398 ssize_t ret;
399 char *data;
400
401 ENTER();
402
403 /* Fast check if setup was canceled */
404 if (FFS_SETUP_STATE(ffs) == FFS_SETUP_CANCELED)
405 return -EIDRM;
406
407 /* Acquire mutex */
408 ret = ffs_mutex_lock(&ffs->mutex, file->f_flags & O_NONBLOCK);
409 if (unlikely(ret < 0))
410 return ret;
411
412
413 /* Check state */
414 switch (ffs->state) {
415 case FFS_READ_DESCRIPTORS:
416 case FFS_READ_STRINGS:
417 /* Copy data */
418 if (unlikely(len < 16)) {
419 ret = -EINVAL;
420 break;
421 }
422
423 data = ffs_prepare_buffer(buf, len);
424 if (unlikely(IS_ERR(data))) {
425 ret = PTR_ERR(data);
426 break;
427 }
428
429 /* Handle data */
430 if (ffs->state == FFS_READ_DESCRIPTORS) {
431 FINFO("read descriptors");
432 ret = __ffs_data_got_descs(ffs, data, len);
433 if (unlikely(ret < 0))
434 break;
435
436 ffs->state = FFS_READ_STRINGS;
437 ret = len;
438 } else {
439 FINFO("read strings");
440 ret = __ffs_data_got_strings(ffs, data, len);
441 if (unlikely(ret < 0))
442 break;
443
444 ret = ffs_epfiles_create(ffs);
445 if (unlikely(ret)) {
446 ffs->state = FFS_CLOSING;
447 break;
448 }
449
450 ffs->state = FFS_ACTIVE;
451 mutex_unlock(&ffs->mutex);
452
453 ret = functionfs_ready_callback(ffs);
454 if (unlikely(ret < 0)) {
455 ffs->state = FFS_CLOSING;
456 return ret;
457 }
458
459 set_bit(FFS_FL_CALL_CLOSED_CALLBACK, &ffs->flags);
460 return len;
461 }
462 break;
463
464
465 case FFS_ACTIVE:
466 data = NULL;
467 /* We're called from user space, we can use _irq
468 * rather then _irqsave */
469 spin_lock_irq(&ffs->ev.waitq.lock);
470 switch (FFS_SETUP_STATE(ffs)) {
471 case FFS_SETUP_CANCELED:
472 ret = -EIDRM;
473 goto done_spin;
474
475 case FFS_NO_SETUP:
476 ret = -ESRCH;
477 goto done_spin;
478
479 case FFS_SETUP_PENDING:
480 break;
481 }
482
483 /* FFS_SETUP_PENDING */
484 if (!(ffs->ev.setup.bRequestType & USB_DIR_IN)) {
485 spin_unlock_irq(&ffs->ev.waitq.lock);
486 ret = __ffs_ep0_stall(ffs);
487 break;
488 }
489
490 /* FFS_SETUP_PENDING and not stall */
491 len = min(len, (size_t)le16_to_cpu(ffs->ev.setup.wLength));
492
493 spin_unlock_irq(&ffs->ev.waitq.lock);
494
495 data = ffs_prepare_buffer(buf, len);
496 if (unlikely(IS_ERR(data))) {
497 ret = PTR_ERR(data);
498 break;
499 }
500
501 spin_lock_irq(&ffs->ev.waitq.lock);
502
503 /* We are guaranteed to be still in FFS_ACTIVE state
504 * but the state of setup could have changed from
505 * FFS_SETUP_PENDING to FFS_SETUP_CANCELED so we need
506 * to check for that. If that happened we copied data
507 * from user space in vain but it's unlikely. */
508 /* For sure we are not in FFS_NO_SETUP since this is
509 * the only place FFS_SETUP_PENDING -> FFS_NO_SETUP
510 * transition can be performed and it's protected by
511 * mutex. */
512
513 if (FFS_SETUP_STATE(ffs) == FFS_SETUP_CANCELED) {
514 ret = -EIDRM;
515done_spin:
516 spin_unlock_irq(&ffs->ev.waitq.lock);
517 } else {
518 /* unlocks spinlock */
519 ret = __ffs_ep0_queue_wait(ffs, data, len);
520 }
521 kfree(data);
522 break;
523
524
525 default:
526 ret = -EBADFD;
527 break;
528 }
529
530
531 mutex_unlock(&ffs->mutex);
532 return ret;
533}
534
535
536
537static ssize_t __ffs_ep0_read_events(struct ffs_data *ffs, char __user *buf,
538 size_t n)
539{
540 /* We are holding ffs->ev.waitq.lock and ffs->mutex and we need
541 * to release them. */
542
543 struct usb_functionfs_event events[n];
544 unsigned i = 0;
545
546 memset(events, 0, sizeof events);
547
548 do {
549 events[i].type = ffs->ev.types[i];
550 if (events[i].type == FUNCTIONFS_SETUP) {
551 events[i].u.setup = ffs->ev.setup;
552 ffs->setup_state = FFS_SETUP_PENDING;
553 }
554 } while (++i < n);
555
556 if (n < ffs->ev.count) {
557 ffs->ev.count -= n;
558 memmove(ffs->ev.types, ffs->ev.types + n,
559 ffs->ev.count * sizeof *ffs->ev.types);
560 } else {
561 ffs->ev.count = 0;
562 }
563
564 spin_unlock_irq(&ffs->ev.waitq.lock);
565 mutex_unlock(&ffs->mutex);
566
567 return unlikely(__copy_to_user(buf, events, sizeof events))
568 ? -EFAULT : sizeof events;
569}
570
571
572static ssize_t ffs_ep0_read(struct file *file, char __user *buf,
573 size_t len, loff_t *ptr)
574{
575 struct ffs_data *ffs = file->private_data;
576 char *data = NULL;
577 size_t n;
578 int ret;
579
580 ENTER();
581
582 /* Fast check if setup was canceled */
583 if (FFS_SETUP_STATE(ffs) == FFS_SETUP_CANCELED)
584 return -EIDRM;
585
586 /* Acquire mutex */
587 ret = ffs_mutex_lock(&ffs->mutex, file->f_flags & O_NONBLOCK);
588 if (unlikely(ret < 0))
589 return ret;
590
591
592 /* Check state */
593 if (ffs->state != FFS_ACTIVE) {
594 ret = -EBADFD;
595 goto done_mutex;
596 }
597
598
599 /* We're called from user space, we can use _irq rather then
600 * _irqsave */
601 spin_lock_irq(&ffs->ev.waitq.lock);
602
603 switch (FFS_SETUP_STATE(ffs)) {
604 case FFS_SETUP_CANCELED:
605 ret = -EIDRM;
606 break;
607
608 case FFS_NO_SETUP:
609 n = len / sizeof(struct usb_functionfs_event);
610 if (unlikely(!n)) {
611 ret = -EINVAL;
612 break;
613 }
614
615 if ((file->f_flags & O_NONBLOCK) && !ffs->ev.count) {
616 ret = -EAGAIN;
617 break;
618 }
619
620 if (unlikely(wait_event_interruptible_exclusive_locked_irq(ffs->ev.waitq, ffs->ev.count))) {
621 ret = -EINTR;
622 break;
623 }
624
625 return __ffs_ep0_read_events(ffs, buf,
626 min(n, (size_t)ffs->ev.count));
627
628
629 case FFS_SETUP_PENDING:
630 if (ffs->ev.setup.bRequestType & USB_DIR_IN) {
631 spin_unlock_irq(&ffs->ev.waitq.lock);
632 ret = __ffs_ep0_stall(ffs);
633 goto done_mutex;
634 }
635
636 len = min(len, (size_t)le16_to_cpu(ffs->ev.setup.wLength));
637
638 spin_unlock_irq(&ffs->ev.waitq.lock);
639
640 if (likely(len)) {
641 data = kmalloc(len, GFP_KERNEL);
642 if (unlikely(!data)) {
643 ret = -ENOMEM;
644 goto done_mutex;
645 }
646 }
647
648 spin_lock_irq(&ffs->ev.waitq.lock);
649
650 /* See ffs_ep0_write() */
651 if (FFS_SETUP_STATE(ffs) == FFS_SETUP_CANCELED) {
652 ret = -EIDRM;
653 break;
654 }
655
656 /* unlocks spinlock */
657 ret = __ffs_ep0_queue_wait(ffs, data, len);
658 if (likely(ret > 0) && unlikely(__copy_to_user(buf, data, len)))
659 ret = -EFAULT;
660 goto done_mutex;
661
662 default:
663 ret = -EBADFD;
664 break;
665 }
666
667 spin_unlock_irq(&ffs->ev.waitq.lock);
668done_mutex:
669 mutex_unlock(&ffs->mutex);
670 kfree(data);
671 return ret;
672}
673
674
675
676static int ffs_ep0_open(struct inode *inode, struct file *file)
677{
678 struct ffs_data *ffs = inode->i_private;
679
680 ENTER();
681
682 if (unlikely(ffs->state == FFS_CLOSING))
683 return -EBUSY;
684
685 file->private_data = ffs;
686 ffs_data_opened(ffs);
687
688 return 0;
689}
690
691
692static int ffs_ep0_release(struct inode *inode, struct file *file)
693{
694 struct ffs_data *ffs = file->private_data;
695
696 ENTER();
697
698 ffs_data_closed(ffs);
699
700 return 0;
701}
702
703
704static long ffs_ep0_ioctl(struct file *file, unsigned code, unsigned long value)
705{
706 struct ffs_data *ffs = file->private_data;
707 struct usb_gadget *gadget = ffs->gadget;
708 long ret;
709
710 ENTER();
711
712 if (code == FUNCTIONFS_INTERFACE_REVMAP) {
713 struct ffs_function *func = ffs->func;
714 ret = func ? ffs_func_revmap_intf(func, value) : -ENODEV;
715 } else if (gadget->ops->ioctl) {
716 lock_kernel();
717 ret = gadget->ops->ioctl(gadget, code, value);
718 unlock_kernel();
719 } else {
720 ret = -ENOTTY;
721 }
722
723 return ret;
724}
725
726
727static const struct file_operations ffs_ep0_operations = {
728 .owner = THIS_MODULE,
729 .llseek = no_llseek,
730
731 .open = ffs_ep0_open,
732 .write = ffs_ep0_write,
733 .read = ffs_ep0_read,
734 .release = ffs_ep0_release,
735 .unlocked_ioctl = ffs_ep0_ioctl,
736};
737
738
739/* "Normal" endpoints operations ********************************************/
740
741
742static void ffs_epfile_io_complete(struct usb_ep *_ep, struct usb_request *req)
743{
744 ENTER();
745 if (likely(req->context)) {
746 struct ffs_ep *ep = _ep->driver_data;
747 ep->status = req->status ? req->status : req->actual;
748 complete(req->context);
749 }
750}
751
752
753static ssize_t ffs_epfile_io(struct file *file,
754 char __user *buf, size_t len, int read)
755{
756 struct ffs_epfile *epfile = file->private_data;
757 struct ffs_ep *ep;
758 char *data = NULL;
759 ssize_t ret;
760 int halt;
761
762 goto first_try;
763 do {
764 spin_unlock_irq(&epfile->ffs->eps_lock);
765 mutex_unlock(&epfile->mutex);
766
767first_try:
768 /* Are we still active? */
769 if (WARN_ON(epfile->ffs->state != FFS_ACTIVE)) {
770 ret = -ENODEV;
771 goto error;
772 }
773
774 /* Wait for endpoint to be enabled */
775 ep = epfile->ep;
776 if (!ep) {
777 if (file->f_flags & O_NONBLOCK) {
778 ret = -EAGAIN;
779 goto error;
780 }
781
782 if (unlikely(wait_event_interruptible
783 (epfile->wait, (ep = epfile->ep)))) {
784 ret = -EINTR;
785 goto error;
786 }
787 }
788
789 /* Do we halt? */
790 halt = !read == !epfile->in;
791 if (halt && epfile->isoc) {
792 ret = -EINVAL;
793 goto error;
794 }
795
796 /* Allocate & copy */
797 if (!halt && !data) {
798 data = kzalloc(len, GFP_KERNEL);
799 if (unlikely(!data))
800 return -ENOMEM;
801
802 if (!read &&
803 unlikely(__copy_from_user(data, buf, len))) {
804 ret = -EFAULT;
805 goto error;
806 }
807 }
808
809 /* We will be using request */
810 ret = ffs_mutex_lock(&epfile->mutex,
811 file->f_flags & O_NONBLOCK);
812 if (unlikely(ret))
813 goto error;
814
815 /* We're called from user space, we can use _irq rather then
816 * _irqsave */
817 spin_lock_irq(&epfile->ffs->eps_lock);
818
819 /* While we were acquiring mutex endpoint got disabled
820 * or changed? */
821 } while (unlikely(epfile->ep != ep));
822
823 /* Halt */
824 if (unlikely(halt)) {
825 if (likely(epfile->ep == ep) && !WARN_ON(!ep->ep))
826 usb_ep_set_halt(ep->ep);
827 spin_unlock_irq(&epfile->ffs->eps_lock);
828 ret = -EBADMSG;
829 } else {
830 /* Fire the request */
831 DECLARE_COMPLETION_ONSTACK(done);
832
833 struct usb_request *req = ep->req;
834 req->context = &done;
835 req->complete = ffs_epfile_io_complete;
836 req->buf = data;
837 req->length = len;
838
839 ret = usb_ep_queue(ep->ep, req, GFP_ATOMIC);
840
841 spin_unlock_irq(&epfile->ffs->eps_lock);
842
843 if (unlikely(ret < 0)) {
844 /* nop */
845 } else if (unlikely(wait_for_completion_interruptible(&done))) {
846 ret = -EINTR;
847 usb_ep_dequeue(ep->ep, req);
848 } else {
849 ret = ep->status;
850 if (read && ret > 0 &&
851 unlikely(copy_to_user(buf, data, ret)))
852 ret = -EFAULT;
853 }
854 }
855
856 mutex_unlock(&epfile->mutex);
857error:
858 kfree(data);
859 return ret;
860}
861
862
863static ssize_t
864ffs_epfile_write(struct file *file, const char __user *buf, size_t len,
865 loff_t *ptr)
866{
867 ENTER();
868
869 return ffs_epfile_io(file, (char __user *)buf, len, 0);
870}
871
872static ssize_t
873ffs_epfile_read(struct file *file, char __user *buf, size_t len, loff_t *ptr)
874{
875 ENTER();
876
877 return ffs_epfile_io(file, buf, len, 1);
878}
879
880static int
881ffs_epfile_open(struct inode *inode, struct file *file)
882{
883 struct ffs_epfile *epfile = inode->i_private;
884
885 ENTER();
886
887 if (WARN_ON(epfile->ffs->state != FFS_ACTIVE))
888 return -ENODEV;
889
890 file->private_data = epfile;
891 ffs_data_opened(epfile->ffs);
892
893 return 0;
894}
895
896static int
897ffs_epfile_release(struct inode *inode, struct file *file)
898{
899 struct ffs_epfile *epfile = inode->i_private;
900
901 ENTER();
902
903 ffs_data_closed(epfile->ffs);
904
905 return 0;
906}
907
908
909static long ffs_epfile_ioctl(struct file *file, unsigned code,
910 unsigned long value)
911{
912 struct ffs_epfile *epfile = file->private_data;
913 int ret;
914
915 ENTER();
916
917 if (WARN_ON(epfile->ffs->state != FFS_ACTIVE))
918 return -ENODEV;
919
920 spin_lock_irq(&epfile->ffs->eps_lock);
921 if (likely(epfile->ep)) {
922 switch (code) {
923 case FUNCTIONFS_FIFO_STATUS:
924 ret = usb_ep_fifo_status(epfile->ep->ep);
925 break;
926 case FUNCTIONFS_FIFO_FLUSH:
927 usb_ep_fifo_flush(epfile->ep->ep);
928 ret = 0;
929 break;
930 case FUNCTIONFS_CLEAR_HALT:
931 ret = usb_ep_clear_halt(epfile->ep->ep);
932 break;
933 case FUNCTIONFS_ENDPOINT_REVMAP:
934 ret = epfile->ep->num;
935 break;
936 default:
937 ret = -ENOTTY;
938 }
939 } else {
940 ret = -ENODEV;
941 }
942 spin_unlock_irq(&epfile->ffs->eps_lock);
943
944 return ret;
945}
946
947
948static const struct file_operations ffs_epfile_operations = {
949 .owner = THIS_MODULE,
950 .llseek = no_llseek,
951
952 .open = ffs_epfile_open,
953 .write = ffs_epfile_write,
954 .read = ffs_epfile_read,
955 .release = ffs_epfile_release,
956 .unlocked_ioctl = ffs_epfile_ioctl,
957};
958
959
960
961/* File system and super block operations ***********************************/
962
963/*
964 * Mounting the filesystem creates a controller file, used first for
965 * function configuration then later for event monitoring.
966 */
967
968
969static struct inode *__must_check
970ffs_sb_make_inode(struct super_block *sb, void *data,
971 const struct file_operations *fops,
972 const struct inode_operations *iops,
973 struct ffs_file_perms *perms)
974{
975 struct inode *inode;
976
977 ENTER();
978
979 inode = new_inode(sb);
980
981 if (likely(inode)) {
982 struct timespec current_time = CURRENT_TIME;
983
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;
991 if (fops)
992 inode->i_fop = fops;
993 if (iops)
994 inode->i_op = iops;
995 }
996
997 return inode;
998}
999
1000
1001/* Create "regular" file */
1002
1003static struct inode *ffs_sb_create_file(struct super_block *sb,
1004 const char *name, void *data,
1005 const struct file_operations *fops,
1006 struct dentry **dentry_p)
1007{
1008 struct ffs_data *ffs = sb->s_fs_info;
1009 struct dentry *dentry;
1010 struct inode *inode;
1011
1012 ENTER();
1013
1014 dentry = d_alloc_name(sb->s_root, name);
1015 if (unlikely(!dentry))
1016 return NULL;
1017
1018 inode = ffs_sb_make_inode(sb, data, fops, NULL, &ffs->file_perms);
1019 if (unlikely(!inode)) {
1020 dput(dentry);
1021 return NULL;
1022 }
1023
1024 d_add(dentry, inode);
1025 if (dentry_p)
1026 *dentry_p = dentry;
1027
1028 return inode;
1029}
1030
1031
1032/* Super block */
1033
1034static const struct super_operations ffs_sb_operations = {
1035 .statfs = simple_statfs,
1036 .drop_inode = generic_delete_inode,
1037};
1038
1039struct ffs_sb_fill_data {
1040 struct ffs_file_perms perms;
1041 umode_t root_mode;
1042 const char *dev_name;
1043};
1044
1045static int ffs_sb_fill(struct super_block *sb, void *_data, int silent)
1046{
1047 struct ffs_sb_fill_data *data = _data;
1048 struct inode *inode;
1049 struct dentry *d;
1050 struct ffs_data *ffs;
1051
1052 ENTER();
1053
1054 /* Initialize data */
1055 ffs = ffs_data_new();
1056 if (unlikely(!ffs))
1057 goto enomem0;
1058
1059 ffs->sb = sb;
1060 ffs->dev_name = data->dev_name;
1061 ffs->file_perms = data->perms;
1062
1063 sb->s_fs_info = ffs;
1064 sb->s_blocksize = PAGE_CACHE_SIZE;
1065 sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
1066 sb->s_magic = FUNCTIONFS_MAGIC;
1067 sb->s_op = &ffs_sb_operations;
1068 sb->s_time_gran = 1;
1069
1070 /* Root inode */
1071 data->perms.mode = data->root_mode;
1072 inode = ffs_sb_make_inode(sb, NULL,
1073 &simple_dir_operations,
1074 &simple_dir_inode_operations,
1075 &data->perms);
1076 if (unlikely(!inode))
1077 goto enomem1;
1078 d = d_alloc_root(inode);
1079 if (unlikely(!d))
1080 goto enomem2;
1081 sb->s_root = d;
1082
1083 /* EP0 file */
1084 if (unlikely(!ffs_sb_create_file(sb, "ep0", ffs,
1085 &ffs_ep0_operations, NULL)))
1086 goto enomem3;
1087
1088 return 0;
1089
1090enomem3:
1091 dput(d);
1092enomem2:
1093 iput(inode);
1094enomem1:
1095 ffs_data_put(ffs);
1096enomem0:
1097 return -ENOMEM;
1098}
1099
1100
1101static int ffs_fs_parse_opts(struct ffs_sb_fill_data *data, char *opts)
1102{
1103 ENTER();
1104
1105 if (!opts || !*opts)
1106 return 0;
1107
1108 for (;;) {
1109 char *end, *eq, *comma;
1110 unsigned long value;
1111
1112 /* Option limit */
1113 comma = strchr(opts, ',');
1114 if (comma)
1115 *comma = 0;
1116
1117 /* Value limit */
1118 eq = strchr(opts, '=');
1119 if (unlikely(!eq)) {
1120 FERR("'=' missing in %s", opts);
1121 return -EINVAL;
1122 }
1123 *eq = 0;
1124
1125 /* Parse value */
1126 value = simple_strtoul(eq + 1, &end, 0);
1127 if (unlikely(*end != ',' && *end != 0)) {
1128 FERR("%s: invalid value: %s", opts, eq + 1);
1129 return -EINVAL;
1130 }
1131
1132 /* Interpret option */
1133 switch (eq - opts) {
1134 case 5:
1135 if (!memcmp(opts, "rmode", 5))
1136 data->root_mode = (value & 0555) | S_IFDIR;
1137 else if (!memcmp(opts, "fmode", 5))
1138 data->perms.mode = (value & 0666) | S_IFREG;
1139 else
1140 goto invalid;
1141 break;
1142
1143 case 4:
1144 if (!memcmp(opts, "mode", 4)) {
1145 data->root_mode = (value & 0555) | S_IFDIR;
1146 data->perms.mode = (value & 0666) | S_IFREG;
1147 } else {
1148 goto invalid;
1149 }
1150 break;
1151
1152 case 3:
1153 if (!memcmp(opts, "uid", 3))
1154 data->perms.uid = value;
1155 else if (!memcmp(opts, "gid", 3))
1156 data->perms.gid = value;
1157 else
1158 goto invalid;
1159 break;
1160
1161 default:
1162invalid:
1163 FERR("%s: invalid option", opts);
1164 return -EINVAL;
1165 }
1166
1167 /* Next iteration */
1168 if (!comma)
1169 break;
1170 opts = comma + 1;
1171 }
1172
1173 return 0;
1174}
1175
1176
1177/* "mount -t functionfs dev_name /dev/function" ends up here */
1178
1179static int
1180ffs_fs_get_sb(struct file_system_type *t, int flags,
1181 const char *dev_name, void *opts, struct vfsmount *mnt)
1182{
1183 struct ffs_sb_fill_data data = {
1184 .perms = {
1185 .mode = S_IFREG | 0600,
1186 .uid = 0,
1187 .gid = 0
1188 },
1189 .root_mode = S_IFDIR | 0500,
1190 };
1191 int ret;
1192
1193 ENTER();
1194
1195 ret = functionfs_check_dev_callback(dev_name);
1196 if (unlikely(ret < 0))
1197 return ret;
1198
1199 ret = ffs_fs_parse_opts(&data, opts);
1200 if (unlikely(ret < 0))
1201 return ret;
1202
1203 data.dev_name = dev_name;
1204 return get_sb_single(t, flags, &data, ffs_sb_fill, mnt);
1205}
1206
1207static void
1208ffs_fs_kill_sb(struct super_block *sb)
1209{
1210 void *ptr;
1211
1212 ENTER();
1213
1214 kill_litter_super(sb);
1215 ptr = xchg(&sb->s_fs_info, NULL);
1216 if (ptr)
1217 ffs_data_put(ptr);
1218}
1219
1220static struct file_system_type ffs_fs_type = {
1221 .owner = THIS_MODULE,
1222 .name = "functionfs",
1223 .get_sb = ffs_fs_get_sb,
1224 .kill_sb = ffs_fs_kill_sb,
1225};
1226
1227
1228
1229/* Driver's main init/cleanup functions *************************************/
1230
1231
1232static int functionfs_init(void)
1233{
1234 int ret;
1235
1236 ENTER();
1237
1238 ret = register_filesystem(&ffs_fs_type);
1239 if (likely(!ret))
1240 FINFO("file system registered");
1241 else
1242 FERR("failed registering file system (%d)", ret);
1243
1244 return ret;
1245}
1246
1247static void functionfs_cleanup(void)
1248{
1249 ENTER();
1250
1251 FINFO("unloading");
1252 unregister_filesystem(&ffs_fs_type);
1253}
1254
1255
1256
1257/* ffs_data and ffs_function construction and destruction code **************/
1258
1259static void ffs_data_clear(struct ffs_data *ffs);
1260static void ffs_data_reset(struct ffs_data *ffs);
1261
1262
1263static void ffs_data_get(struct ffs_data *ffs)
1264{
1265 ENTER();
1266
1267 atomic_inc(&ffs->ref);
1268}
1269
1270static void ffs_data_opened(struct ffs_data *ffs)
1271{
1272 ENTER();
1273
1274 atomic_inc(&ffs->ref);
1275 atomic_inc(&ffs->opened);
1276}
1277
1278static void ffs_data_put(struct ffs_data *ffs)
1279{
1280 ENTER();
1281
1282 if (unlikely(atomic_dec_and_test(&ffs->ref))) {
1283 FINFO("%s(): freeing", __func__);
1284 ffs_data_clear(ffs);
1285 BUG_ON(mutex_is_locked(&ffs->mutex) ||
1286 spin_is_locked(&ffs->ev.waitq.lock) ||
1287 waitqueue_active(&ffs->ev.waitq) ||
1288 waitqueue_active(&ffs->ep0req_completion.wait));
1289 kfree(ffs);
1290 }
1291}
1292
1293
1294
1295static void ffs_data_closed(struct ffs_data *ffs)
1296{
1297 ENTER();
1298
1299 if (atomic_dec_and_test(&ffs->opened)) {
1300 ffs->state = FFS_CLOSING;
1301 ffs_data_reset(ffs);
1302 }
1303
1304 ffs_data_put(ffs);
1305}
1306
1307
1308static struct ffs_data *ffs_data_new(void)
1309{
1310 struct ffs_data *ffs = kzalloc(sizeof *ffs, GFP_KERNEL);
1311 if (unlikely(!ffs))
1312 return 0;
1313
1314 ENTER();
1315
1316 atomic_set(&ffs->ref, 1);
1317 atomic_set(&ffs->opened, 0);
1318 ffs->state = FFS_READ_DESCRIPTORS;
1319 mutex_init(&ffs->mutex);
1320 spin_lock_init(&ffs->eps_lock);
1321 init_waitqueue_head(&ffs->ev.waitq);
1322 init_completion(&ffs->ep0req_completion);
1323
1324 /* XXX REVISIT need to update it in some places, or do we? */
1325 ffs->ev.can_stall = 1;
1326
1327 return ffs;
1328}
1329
1330
1331static void ffs_data_clear(struct ffs_data *ffs)
1332{
1333 ENTER();
1334
1335 if (test_and_clear_bit(FFS_FL_CALL_CLOSED_CALLBACK, &ffs->flags))
1336 functionfs_closed_callback(ffs);
1337
1338 BUG_ON(ffs->gadget);
1339
1340 if (ffs->epfiles)
1341 ffs_epfiles_destroy(ffs->epfiles, ffs->eps_count);
1342
1343 kfree(ffs->raw_descs);
1344 kfree(ffs->raw_strings);
1345 kfree(ffs->stringtabs);
1346}
1347
1348
1349static void ffs_data_reset(struct ffs_data *ffs)
1350{
1351 ENTER();
1352
1353 ffs_data_clear(ffs);
1354
1355 ffs->epfiles = NULL;
1356 ffs->raw_descs = NULL;
1357 ffs->raw_strings = NULL;
1358 ffs->stringtabs = NULL;
1359
1360 ffs->raw_descs_length = 0;
1361 ffs->raw_fs_descs_length = 0;
1362 ffs->fs_descs_count = 0;
1363 ffs->hs_descs_count = 0;
1364
1365 ffs->strings_count = 0;
1366 ffs->interfaces_count = 0;
1367 ffs->eps_count = 0;
1368
1369 ffs->ev.count = 0;
1370
1371 ffs->state = FFS_READ_DESCRIPTORS;
1372 ffs->setup_state = FFS_NO_SETUP;
1373 ffs->flags = 0;
1374}
1375
1376
1377static int functionfs_bind(struct ffs_data *ffs, struct usb_composite_dev *cdev)
1378{
1379 unsigned i, count;
1380
1381 ENTER();
1382
1383 if (WARN_ON(ffs->state != FFS_ACTIVE
1384 || test_and_set_bit(FFS_FL_BOUND, &ffs->flags)))
1385 return -EBADFD;
1386
1387 ffs_data_get(ffs);
1388
1389 ffs->ep0req = usb_ep_alloc_request(cdev->gadget->ep0, GFP_KERNEL);
1390 if (unlikely(!ffs->ep0req))
1391 return -ENOMEM;
1392 ffs->ep0req->complete = ffs_ep0_complete;
1393 ffs->ep0req->context = ffs;
1394
1395 /* Get strings identifiers */
1396 for (count = ffs->strings_count, i = 0; i < count; ++i) {
1397 struct usb_gadget_strings **lang;
1398
1399 int id = usb_string_id(cdev);
1400 if (unlikely(id < 0)) {
1401 usb_ep_free_request(cdev->gadget->ep0, ffs->ep0req);
1402 ffs->ep0req = NULL;
1403 return id;
1404 }
1405
1406 lang = ffs->stringtabs;
1407 do {
1408 (*lang)->strings[i].id = id;
1409 ++lang;
1410 } while (*lang);
1411 }
1412
1413 ffs->gadget = cdev->gadget;
1414 return 0;
1415}
1416
1417
1418static void functionfs_unbind(struct ffs_data *ffs)
1419{
1420 ENTER();
1421
1422 if (!WARN_ON(!ffs->gadget)) {
1423 usb_ep_free_request(ffs->gadget->ep0, ffs->ep0req);
1424 ffs->ep0req = NULL;
1425 ffs->gadget = NULL;
1426 ffs_data_put(ffs);
1427 }
1428}
1429
1430
1431static int ffs_epfiles_create(struct ffs_data *ffs)
1432{
1433 struct ffs_epfile *epfile, *epfiles;
1434 unsigned i, count;
1435
1436 ENTER();
1437
1438 count = ffs->eps_count;
1439 epfiles = kzalloc(count * sizeof *epfiles, GFP_KERNEL);
1440 if (!epfiles)
1441 return -ENOMEM;
1442
1443 epfile = epfiles;
1444 for (i = 1; i <= count; ++i, ++epfile) {
1445 epfile->ffs = ffs;
1446 mutex_init(&epfile->mutex);
1447 init_waitqueue_head(&epfile->wait);
1448 sprintf(epfiles->name, "ep%u", i);
1449 if (!unlikely(ffs_sb_create_file(ffs->sb, epfiles->name, epfile,
1450 &ffs_epfile_operations,
1451 &epfile->dentry))) {
1452 ffs_epfiles_destroy(epfiles, i - 1);
1453 return -ENOMEM;
1454 }
1455 }
1456
1457 ffs->epfiles = epfiles;
1458 return 0;
1459}
1460
1461
1462static void ffs_epfiles_destroy(struct ffs_epfile *epfiles, unsigned count)
1463{
1464 struct ffs_epfile *epfile = epfiles;
1465
1466 ENTER();
1467
1468 for (; count; --count, ++epfile) {
1469 BUG_ON(mutex_is_locked(&epfile->mutex) ||
1470 waitqueue_active(&epfile->wait));
1471 if (epfile->dentry) {
1472 d_delete(epfile->dentry);
1473 dput(epfile->dentry);
1474 epfile->dentry = NULL;
1475 }
1476 }
1477
1478 kfree(epfiles);
1479}
1480
1481
1482static int functionfs_add(struct usb_composite_dev *cdev,
1483 struct usb_configuration *c,
1484 struct ffs_data *ffs)
1485{
1486 struct ffs_function *func;
1487 int ret;
1488
1489 ENTER();
1490
1491 func = kzalloc(sizeof *func, GFP_KERNEL);
1492 if (unlikely(!func))
1493 return -ENOMEM;
1494
1495 func->function.name = "Function FS Gadget";
1496 func->function.strings = ffs->stringtabs;
1497
1498 func->function.bind = ffs_func_bind;
1499 func->function.unbind = ffs_func_unbind;
1500 func->function.set_alt = ffs_func_set_alt;
1501 /*func->function.get_alt = ffs_func_get_alt;*/
1502 func->function.disable = ffs_func_disable;
1503 func->function.setup = ffs_func_setup;
1504 func->function.suspend = ffs_func_suspend;
1505 func->function.resume = ffs_func_resume;
1506
1507 func->conf = c;
1508 func->gadget = cdev->gadget;
1509 func->ffs = ffs;
1510 ffs_data_get(ffs);
1511
1512 ret = usb_add_function(c, &func->function);
1513 if (unlikely(ret))
1514 ffs_func_free(func);
1515
1516 return ret;
1517}
1518
1519static void ffs_func_free(struct ffs_function *func)
1520{
1521 ENTER();
1522
1523 ffs_data_put(func->ffs);
1524
1525 kfree(func->eps);
1526 /* eps and interfaces_nums are allocated in the same chunk so
1527 * only one free is required. Descriptors are also allocated
1528 * in the same chunk. */
1529
1530 kfree(func);
1531}
1532
1533
1534static void ffs_func_eps_disable(struct ffs_function *func)
1535{
1536 struct ffs_ep *ep = func->eps;
1537 struct ffs_epfile *epfile = func->ffs->epfiles;
1538 unsigned count = func->ffs->eps_count;
1539 unsigned long flags;
1540
1541 spin_lock_irqsave(&func->ffs->eps_lock, flags);
1542 do {
1543 /* pending requests get nuked */
1544 if (likely(ep->ep))
1545 usb_ep_disable(ep->ep);
1546 epfile->ep = NULL;
1547
1548 ++ep;
1549 ++epfile;
1550 } while (--count);
1551 spin_unlock_irqrestore(&func->ffs->eps_lock, flags);
1552}
1553
1554static int ffs_func_eps_enable(struct ffs_function *func)
1555{
1556 struct ffs_data *ffs = func->ffs;
1557 struct ffs_ep *ep = func->eps;
1558 struct ffs_epfile *epfile = ffs->epfiles;
1559 unsigned count = ffs->eps_count;
1560 unsigned long flags;
1561 int ret = 0;
1562
1563 spin_lock_irqsave(&func->ffs->eps_lock, flags);
1564 do {
1565 struct usb_endpoint_descriptor *ds;
1566 ds = ep->descs[ep->descs[1] ? 1 : 0];
1567
1568 ep->ep->driver_data = ep;
1569 ret = usb_ep_enable(ep->ep, ds);
1570 if (likely(!ret)) {
1571 epfile->ep = ep;
1572 epfile->in = usb_endpoint_dir_in(ds);
1573 epfile->isoc = usb_endpoint_xfer_isoc(ds);
1574 } else {
1575 break;
1576 }
1577
1578 wake_up(&epfile->wait);
1579
1580 ++ep;
1581 ++epfile;
1582 } while (--count);
1583 spin_unlock_irqrestore(&func->ffs->eps_lock, flags);
1584
1585 return ret;
1586}
1587
1588
1589/* Parsing and building descriptors and strings *****************************/
1590
1591
1592/* This validates if data pointed by data is a valid USB descriptor as
1593 * well as record how many interfaces, endpoints and strings are
1594 * required by given configuration. Returns address afther the
1595 * descriptor or NULL if data is invalid. */
1596
1597enum ffs_entity_type {
1598 FFS_DESCRIPTOR, FFS_INTERFACE, FFS_STRING, FFS_ENDPOINT
1599};
1600
1601typedef int (*ffs_entity_callback)(enum ffs_entity_type entity,
1602 u8 *valuep,
1603 struct usb_descriptor_header *desc,
1604 void *priv);
1605
1606static int __must_check ffs_do_desc(char *data, unsigned len,
1607 ffs_entity_callback entity, void *priv)
1608{
1609 struct usb_descriptor_header *_ds = (void *)data;
1610 u8 length;
1611 int ret;
1612
1613 ENTER();
1614
1615 /* At least two bytes are required: length and type */
1616 if (len < 2) {
1617 FVDBG("descriptor too short");
1618 return -EINVAL;
1619 }
1620
1621 /* If we have at least as many bytes as the descriptor takes? */
1622 length = _ds->bLength;
1623 if (len < length) {
1624 FVDBG("descriptor longer then available data");
1625 return -EINVAL;
1626 }
1627
1628#define __entity_check_INTERFACE(val) 1
1629#define __entity_check_STRING(val) (val)
1630#define __entity_check_ENDPOINT(val) ((val) & USB_ENDPOINT_NUMBER_MASK)
1631#define __entity(type, val) do { \
1632 FVDBG("entity " #type "(%02x)", (val)); \
1633 if (unlikely(!__entity_check_ ##type(val))) { \
1634 FVDBG("invalid entity's value"); \
1635 return -EINVAL; \
1636 } \
1637 ret = entity(FFS_ ##type, &val, _ds, priv); \
1638 if (unlikely(ret < 0)) { \
1639 FDBG("entity " #type "(%02x); ret = %d", \
1640 (val), ret); \
1641 return ret; \
1642 } \
1643 } while (0)
1644
1645 /* Parse descriptor depending on type. */
1646 switch (_ds->bDescriptorType) {
1647 case USB_DT_DEVICE:
1648 case USB_DT_CONFIG:
1649 case USB_DT_STRING:
1650 case USB_DT_DEVICE_QUALIFIER:
1651 /* function can't have any of those */
1652 FVDBG("descriptor reserved for gadget: %d", _ds->bDescriptorType);
1653 return -EINVAL;
1654
1655 case USB_DT_INTERFACE: {
1656 struct usb_interface_descriptor *ds = (void *)_ds;
1657 FVDBG("interface descriptor");
1658 if (length != sizeof *ds)
1659 goto inv_length;
1660
1661 __entity(INTERFACE, ds->bInterfaceNumber);
1662 if (ds->iInterface)
1663 __entity(STRING, ds->iInterface);
1664 }
1665 break;
1666
1667 case USB_DT_ENDPOINT: {
1668 struct usb_endpoint_descriptor *ds = (void *)_ds;
1669 FVDBG("endpoint descriptor");
1670 if (length != USB_DT_ENDPOINT_SIZE &&
1671 length != USB_DT_ENDPOINT_AUDIO_SIZE)
1672 goto inv_length;
1673 __entity(ENDPOINT, ds->bEndpointAddress);
1674 }
1675 break;
1676
1677 case USB_DT_OTG:
1678 if (length != sizeof(struct usb_otg_descriptor))
1679 goto inv_length;
1680 break;
1681
1682 case USB_DT_INTERFACE_ASSOCIATION: {
1683 struct usb_interface_assoc_descriptor *ds = (void *)_ds;
1684 FVDBG("interface association descriptor");
1685 if (length != sizeof *ds)
1686 goto inv_length;
1687 if (ds->iFunction)
1688 __entity(STRING, ds->iFunction);
1689 }
1690 break;
1691
1692 case USB_DT_OTHER_SPEED_CONFIG:
1693 case USB_DT_INTERFACE_POWER:
1694 case USB_DT_DEBUG:
1695 case USB_DT_SECURITY:
1696 case USB_DT_CS_RADIO_CONTROL:
1697 /* TODO */
1698 FVDBG("unimplemented descriptor: %d", _ds->bDescriptorType);
1699 return -EINVAL;
1700
1701 default:
1702 /* We should never be here */
1703 FVDBG("unknown descriptor: %d", _ds->bDescriptorType);
1704 return -EINVAL;
1705
1706 inv_length:
1707 FVDBG("invalid length: %d (descriptor %d)",
1708 _ds->bLength, _ds->bDescriptorType);
1709 return -EINVAL;
1710 }
1711
1712#undef __entity
1713#undef __entity_check_DESCRIPTOR
1714#undef __entity_check_INTERFACE
1715#undef __entity_check_STRING
1716#undef __entity_check_ENDPOINT
1717
1718 return length;
1719}
1720
1721
1722static int __must_check ffs_do_descs(unsigned count, char *data, unsigned len,
1723 ffs_entity_callback entity, void *priv)
1724{
1725 const unsigned _len = len;
1726 unsigned long num = 0;
1727
1728 ENTER();
1729
1730 for (;;) {
1731 int ret;
1732
1733 if (num == count)
1734 data = NULL;
1735
1736 /* Record "descriptor" entitny */
1737 ret = entity(FFS_DESCRIPTOR, (u8 *)num, (void *)data, priv);
1738 if (unlikely(ret < 0)) {
1739 FDBG("entity DESCRIPTOR(%02lx); ret = %d", num, ret);
1740 return ret;
1741 }
1742
1743 if (!data)
1744 return _len - len;
1745
1746 ret = ffs_do_desc(data, len, entity, priv);
1747 if (unlikely(ret < 0)) {
1748 FDBG("%s returns %d", __func__, ret);
1749 return ret;
1750 }
1751
1752 len -= ret;
1753 data += ret;
1754 ++num;
1755 }
1756}
1757
1758
1759static int __ffs_data_do_entity(enum ffs_entity_type type,
1760 u8 *valuep, struct usb_descriptor_header *desc,
1761 void *priv)
1762{
1763 struct ffs_data *ffs = priv;
1764
1765 ENTER();
1766
1767 switch (type) {
1768 case FFS_DESCRIPTOR:
1769 break;
1770
1771 case FFS_INTERFACE:
1772 /* Interfaces are indexed from zero so if we
1773 * encountered interface "n" then there are at least
1774 * "n+1" interfaces. */
1775 if (*valuep >= ffs->interfaces_count)
1776 ffs->interfaces_count = *valuep + 1;
1777 break;
1778
1779 case FFS_STRING:
1780 /* Strings are indexed from 1 (0 is magic ;) reserved
1781 * for languages list or some such) */
1782 if (*valuep > ffs->strings_count)
1783 ffs->strings_count = *valuep;
1784 break;
1785
1786 case FFS_ENDPOINT:
1787 /* Endpoints are indexed from 1 as well. */
1788 if ((*valuep & USB_ENDPOINT_NUMBER_MASK) > ffs->eps_count)
1789 ffs->eps_count = (*valuep & USB_ENDPOINT_NUMBER_MASK);
1790 break;
1791 }
1792
1793 return 0;
1794}
1795
1796
1797static int __ffs_data_got_descs(struct ffs_data *ffs,
1798 char *const _data, size_t len)
1799{
1800 unsigned fs_count, hs_count;
1801 int fs_len, ret = -EINVAL;
1802 char *data = _data;
1803
1804 ENTER();
1805
1806 if (unlikely(get_unaligned_le32(data) != FUNCTIONFS_DESCRIPTORS_MAGIC ||
1807 get_unaligned_le32(data + 4) != len))
1808 goto error;
1809 fs_count = get_unaligned_le32(data + 8);
1810 hs_count = get_unaligned_le32(data + 12);
1811
1812 if (!fs_count && !hs_count)
1813 goto einval;
1814
1815 data += 16;
1816 len -= 16;
1817
1818 if (likely(fs_count)) {
1819 fs_len = ffs_do_descs(fs_count, data, len,
1820 __ffs_data_do_entity, ffs);
1821 if (unlikely(fs_len < 0)) {
1822 ret = fs_len;
1823 goto error;
1824 }
1825
1826 data += fs_len;
1827 len -= fs_len;
1828 } else {
1829 fs_len = 0;
1830 }
1831
1832 if (likely(hs_count)) {
1833 ret = ffs_do_descs(hs_count, data, len,
1834 __ffs_data_do_entity, ffs);
1835 if (unlikely(ret < 0))
1836 goto error;
1837 } else {
1838 ret = 0;
1839 }
1840
1841 if (unlikely(len != ret))
1842 goto einval;
1843
1844 ffs->raw_fs_descs_length = fs_len;
1845 ffs->raw_descs_length = fs_len + ret;
1846 ffs->raw_descs = _data;
1847 ffs->fs_descs_count = fs_count;
1848 ffs->hs_descs_count = hs_count;
1849
1850 return 0;
1851
1852einval:
1853 ret = -EINVAL;
1854error:
1855 kfree(_data);
1856 return ret;
1857}
1858
1859
1860
1861static int __ffs_data_got_strings(struct ffs_data *ffs,
1862 char *const _data, size_t len)
1863{
1864 u32 str_count, needed_count, lang_count;
1865 struct usb_gadget_strings **stringtabs, *t;
1866 struct usb_string *strings, *s;
1867 const char *data = _data;
1868
1869 ENTER();
1870
1871 if (unlikely(get_unaligned_le32(data) != FUNCTIONFS_STRINGS_MAGIC ||
1872 get_unaligned_le32(data + 4) != len))
1873 goto error;
1874 str_count = get_unaligned_le32(data + 8);
1875 lang_count = get_unaligned_le32(data + 12);
1876
1877 /* if one is zero the other must be zero */
1878 if (unlikely(!str_count != !lang_count))
1879 goto error;
1880
1881 /* Do we have at least as many strings as descriptors need? */
1882 needed_count = ffs->strings_count;
1883 if (unlikely(str_count < needed_count))
1884 goto error;
1885
1886 /* If we don't need any strings just return and free all
1887 * memory */
1888 if (!needed_count) {
1889 kfree(_data);
1890 return 0;
1891 }
1892
1893 /* Allocate */
1894 {
1895 /* Allocate everything in one chunk so there's less
1896 * maintanance. */
1897 struct {
1898 struct usb_gadget_strings *stringtabs[lang_count + 1];
1899 struct usb_gadget_strings stringtab[lang_count];
1900 struct usb_string strings[lang_count*(needed_count+1)];
1901 } *d;
1902 unsigned i = 0;
1903
1904 d = kmalloc(sizeof *d, GFP_KERNEL);
1905 if (unlikely(!d)) {
1906 kfree(_data);
1907 return -ENOMEM;
1908 }
1909
1910 stringtabs = d->stringtabs;
1911 t = d->stringtab;
1912 i = lang_count;
1913 do {
1914 *stringtabs++ = t++;
1915 } while (--i);
1916 *stringtabs = NULL;
1917
1918 stringtabs = d->stringtabs;
1919 t = d->stringtab;
1920 s = d->strings;
1921 strings = s;
1922 }
1923
1924 /* For each language */
1925 data += 16;
1926 len -= 16;
1927
1928 do { /* lang_count > 0 so we can use do-while */
1929 unsigned needed = needed_count;
1930
1931 if (unlikely(len < 3))
1932 goto error_free;
1933 t->language = get_unaligned_le16(data);
1934 t->strings = s;
1935 ++t;
1936
1937 data += 2;
1938 len -= 2;
1939
1940 /* For each string */
1941 do { /* str_count > 0 so we can use do-while */
1942 size_t length = strnlen(data, len);
1943
1944 if (unlikely(length == len))
1945 goto error_free;
1946
1947 /* user may provide more strings then we need,
1948 * if that's the case we simply ingore the
1949 * rest */
1950 if (likely(needed)) {
1951 /* s->id will be set while adding
1952 * function to configuration so for
1953 * now just leave garbage here. */
1954 s->s = data;
1955 --needed;
1956 ++s;
1957 }
1958
1959 data += length + 1;
1960 len -= length + 1;
1961 } while (--str_count);
1962
1963 s->id = 0; /* terminator */
1964 s->s = NULL;
1965 ++s;
1966
1967 } while (--lang_count);
1968
1969 /* Some garbage left? */
1970 if (unlikely(len))
1971 goto error_free;
1972
1973 /* Done! */
1974 ffs->stringtabs = stringtabs;
1975 ffs->raw_strings = _data;
1976
1977 return 0;
1978
1979error_free:
1980 kfree(stringtabs);
1981error:
1982 kfree(_data);
1983 return -EINVAL;
1984}
1985
1986
1987
1988
1989/* Events handling and management *******************************************/
1990
1991static void __ffs_event_add(struct ffs_data *ffs,
1992 enum usb_functionfs_event_type type)
1993{
1994 enum usb_functionfs_event_type rem_type1, rem_type2 = type;
1995 int neg = 0;
1996
1997 /* Abort any unhandled setup */
1998 /* We do not need to worry about some cmpxchg() changing value
1999 * of ffs->setup_state without holding the lock because when
2000 * state is FFS_SETUP_PENDING cmpxchg() in several places in
2001 * the source does nothing. */
2002 if (ffs->setup_state == FFS_SETUP_PENDING)
2003 ffs->setup_state = FFS_SETUP_CANCELED;
2004
2005 switch (type) {
2006 case FUNCTIONFS_RESUME:
2007 rem_type2 = FUNCTIONFS_SUSPEND;
2008 /* FALL THGOUTH */
2009 case FUNCTIONFS_SUSPEND:
2010 case FUNCTIONFS_SETUP:
2011 rem_type1 = type;
2012 /* discard all similar events */
2013 break;
2014
2015 case FUNCTIONFS_BIND:
2016 case FUNCTIONFS_UNBIND:
2017 case FUNCTIONFS_DISABLE:
2018 case FUNCTIONFS_ENABLE:
2019 /* discard everything other then power management. */
2020 rem_type1 = FUNCTIONFS_SUSPEND;
2021 rem_type2 = FUNCTIONFS_RESUME;
2022 neg = 1;
2023 break;
2024
2025 default:
2026 BUG();
2027 }
2028
2029 {
2030 u8 *ev = ffs->ev.types, *out = ev;
2031 unsigned n = ffs->ev.count;
2032 for (; n; --n, ++ev)
2033 if ((*ev == rem_type1 || *ev == rem_type2) == neg)
2034 *out++ = *ev;
2035 else
2036 FVDBG("purging event %d", *ev);
2037 ffs->ev.count = out - ffs->ev.types;
2038 }
2039
2040 FVDBG("adding event %d", type);
2041 ffs->ev.types[ffs->ev.count++] = type;
2042 wake_up_locked(&ffs->ev.waitq);
2043}
2044
2045static void ffs_event_add(struct ffs_data *ffs,
2046 enum usb_functionfs_event_type type)
2047{
2048 unsigned long flags;
2049 spin_lock_irqsave(&ffs->ev.waitq.lock, flags);
2050 __ffs_event_add(ffs, type);
2051 spin_unlock_irqrestore(&ffs->ev.waitq.lock, flags);
2052}
2053
2054
2055/* Bind/unbind USB function hooks *******************************************/
2056
2057static int __ffs_func_bind_do_descs(enum ffs_entity_type type, u8 *valuep,
2058 struct usb_descriptor_header *desc,
2059 void *priv)
2060{
2061 struct usb_endpoint_descriptor *ds = (void *)desc;
2062 struct ffs_function *func = priv;
2063 struct ffs_ep *ffs_ep;
2064
2065 /* If hs_descriptors is not NULL then we are reading hs
2066 * descriptors now */
2067 const int isHS = func->function.hs_descriptors != NULL;
2068 unsigned idx;
2069
2070 if (type != FFS_DESCRIPTOR)
2071 return 0;
2072
2073 if (isHS)
2074 func->function.hs_descriptors[(long)valuep] = desc;
2075 else
2076 func->function.descriptors[(long)valuep] = desc;
2077
2078 if (!desc || desc->bDescriptorType != USB_DT_ENDPOINT)
2079 return 0;
2080
2081 idx = (ds->bEndpointAddress & USB_ENDPOINT_NUMBER_MASK) - 1;
2082 ffs_ep = func->eps + idx;
2083
2084 if (unlikely(ffs_ep->descs[isHS])) {
2085 FVDBG("two %sspeed descriptors for EP %d",
2086 isHS ? "high" : "full",
2087 ds->bEndpointAddress & USB_ENDPOINT_NUMBER_MASK);
2088 return -EINVAL;
2089 }
2090 ffs_ep->descs[isHS] = ds;
2091
2092 ffs_dump_mem(": Original ep desc", ds, ds->bLength);
2093 if (ffs_ep->ep) {
2094 ds->bEndpointAddress = ffs_ep->descs[0]->bEndpointAddress;
2095 if (!ds->wMaxPacketSize)
2096 ds->wMaxPacketSize = ffs_ep->descs[0]->wMaxPacketSize;
2097 } else {
2098 struct usb_request *req;
2099 struct usb_ep *ep;
2100
2101 FVDBG("autoconfig");
2102 ep = usb_ep_autoconfig(func->gadget, ds);
2103 if (unlikely(!ep))
2104 return -ENOTSUPP;
2105 ep->driver_data = func->eps + idx;;
2106
2107 req = usb_ep_alloc_request(ep, GFP_KERNEL);
2108 if (unlikely(!req))
2109 return -ENOMEM;
2110
2111 ffs_ep->ep = ep;
2112 ffs_ep->req = req;
2113 func->eps_revmap[ds->bEndpointAddress &
2114 USB_ENDPOINT_NUMBER_MASK] = idx + 1;
2115 }
2116 ffs_dump_mem(": Rewritten ep desc", ds, ds->bLength);
2117
2118 return 0;
2119}
2120
2121
2122static int __ffs_func_bind_do_nums(enum ffs_entity_type type, u8 *valuep,
2123 struct usb_descriptor_header *desc,
2124 void *priv)
2125{
2126 struct ffs_function *func = priv;
2127 unsigned idx;
2128 u8 newValue;
2129
2130 switch (type) {
2131 default:
2132 case FFS_DESCRIPTOR:
2133 /* Handled in previous pass by __ffs_func_bind_do_descs() */
2134 return 0;
2135
2136 case FFS_INTERFACE:
2137 idx = *valuep;
2138 if (func->interfaces_nums[idx] < 0) {
2139 int id = usb_interface_id(func->conf, &func->function);
2140 if (unlikely(id < 0))
2141 return id;
2142 func->interfaces_nums[idx] = id;
2143 }
2144 newValue = func->interfaces_nums[idx];
2145 break;
2146
2147 case FFS_STRING:
2148 /* String' IDs are allocated when fsf_data is bound to cdev */
2149 newValue = func->ffs->stringtabs[0]->strings[*valuep - 1].id;
2150 break;
2151
2152 case FFS_ENDPOINT:
2153 /* USB_DT_ENDPOINT are handled in
2154 * __ffs_func_bind_do_descs(). */
2155 if (desc->bDescriptorType == USB_DT_ENDPOINT)
2156 return 0;
2157
2158 idx = (*valuep & USB_ENDPOINT_NUMBER_MASK) - 1;
2159 if (unlikely(!func->eps[idx].ep))
2160 return -EINVAL;
2161
2162 {
2163 struct usb_endpoint_descriptor **descs;
2164 descs = func->eps[idx].descs;
2165 newValue = descs[descs[0] ? 0 : 1]->bEndpointAddress;
2166 }
2167 break;
2168 }
2169
2170 FVDBG("%02x -> %02x", *valuep, newValue);
2171 *valuep = newValue;
2172 return 0;
2173}
2174
2175static int ffs_func_bind(struct usb_configuration *c,
2176 struct usb_function *f)
2177{
2178 struct ffs_function *func = ffs_func_from_usb(f);
2179 struct ffs_data *ffs = func->ffs;
2180
2181 const int full = !!func->ffs->fs_descs_count;
2182 const int high = gadget_is_dualspeed(func->gadget) &&
2183 func->ffs->hs_descs_count;
2184
2185 int ret;
2186
2187 /* Make it a single chunk, less management later on */
2188 struct {
2189 struct ffs_ep eps[ffs->eps_count];
2190 struct usb_descriptor_header
2191 *fs_descs[full ? ffs->fs_descs_count + 1 : 0];
2192 struct usb_descriptor_header
2193 *hs_descs[high ? ffs->hs_descs_count + 1 : 0];
2194 short inums[ffs->interfaces_count];
2195 char raw_descs[high ? ffs->raw_descs_length
2196 : ffs->raw_fs_descs_length];
2197 } *data;
2198
2199 ENTER();
2200
2201 /* Only high speed but not supported by gadget? */
2202 if (unlikely(!(full | high)))
2203 return -ENOTSUPP;
2204
2205 /* Allocate */
2206 data = kmalloc(sizeof *data, GFP_KERNEL);
2207 if (unlikely(!data))
2208 return -ENOMEM;
2209
2210 /* Zero */
2211 memset(data->eps, 0, sizeof data->eps);
2212 memcpy(data->raw_descs, ffs->raw_descs + 16, sizeof data->raw_descs);
2213 memset(data->inums, 0xff, sizeof data->inums);
2214 for (ret = ffs->eps_count; ret; --ret)
2215 data->eps[ret].num = -1;
2216
2217 /* Save pointers */
2218 func->eps = data->eps;
2219 func->interfaces_nums = data->inums;
2220
2221 /* Go throught all the endpoint descriptors and allocate
2222 * endpoints first, so that later we can rewrite the endpoint
2223 * numbers without worying that it may be described later on. */
2224 if (likely(full)) {
2225 func->function.descriptors = data->fs_descs;
2226 ret = ffs_do_descs(ffs->fs_descs_count,
2227 data->raw_descs,
2228 sizeof data->raw_descs,
2229 __ffs_func_bind_do_descs, func);
2230 if (unlikely(ret < 0))
2231 goto error;
2232 } else {
2233 ret = 0;
2234 }
2235
2236 if (likely(high)) {
2237 func->function.hs_descriptors = data->hs_descs;
2238 ret = ffs_do_descs(ffs->hs_descs_count,
2239 data->raw_descs + ret,
2240 (sizeof data->raw_descs) - ret,
2241 __ffs_func_bind_do_descs, func);
2242 }
2243
2244 /* Now handle interface numbers allocation and interface and
2245 * enpoint numbers rewritting. We can do that in one go
2246 * now. */
2247 ret = ffs_do_descs(ffs->fs_descs_count +
2248 (high ? ffs->hs_descs_count : 0),
2249 data->raw_descs, sizeof data->raw_descs,
2250 __ffs_func_bind_do_nums, func);
2251 if (unlikely(ret < 0))
2252 goto error;
2253
2254 /* And we're done */
2255 ffs_event_add(ffs, FUNCTIONFS_BIND);
2256 return 0;
2257
2258error:
2259 /* XXX Do we need to release all claimed endpoints here? */
2260 return ret;
2261}
2262
2263
2264/* Other USB function hooks *************************************************/
2265
2266static void ffs_func_unbind(struct usb_configuration *c,
2267 struct usb_function *f)
2268{
2269 struct ffs_function *func = ffs_func_from_usb(f);
2270 struct ffs_data *ffs = func->ffs;
2271
2272 ENTER();
2273
2274 if (ffs->func == func) {
2275 ffs_func_eps_disable(func);
2276 ffs->func = NULL;
2277 }
2278
2279 ffs_event_add(ffs, FUNCTIONFS_UNBIND);
2280
2281 ffs_func_free(func);
2282}
2283
2284
2285static int ffs_func_set_alt(struct usb_function *f,
2286 unsigned interface, unsigned alt)
2287{
2288 struct ffs_function *func = ffs_func_from_usb(f);
2289 struct ffs_data *ffs = func->ffs;
2290 int ret = 0, intf;
2291
2292 if (alt != (unsigned)-1) {
2293 intf = ffs_func_revmap_intf(func, interface);
2294 if (unlikely(intf < 0))
2295 return intf;
2296 }
2297
2298 if (ffs->func)
2299 ffs_func_eps_disable(ffs->func);
2300
2301 if (ffs->state != FFS_ACTIVE)
2302 return -ENODEV;
2303
2304 if (alt == (unsigned)-1) {
2305 ffs->func = NULL;
2306 ffs_event_add(ffs, FUNCTIONFS_DISABLE);
2307 return 0;
2308 }
2309
2310 ffs->func = func;
2311 ret = ffs_func_eps_enable(func);
2312 if (likely(ret >= 0))
2313 ffs_event_add(ffs, FUNCTIONFS_ENABLE);
2314 return ret;
2315}
2316
2317static void ffs_func_disable(struct usb_function *f)
2318{
2319 ffs_func_set_alt(f, 0, (unsigned)-1);
2320}
2321
2322static int ffs_func_setup(struct usb_function *f,
2323 const struct usb_ctrlrequest *creq)
2324{
2325 struct ffs_function *func = ffs_func_from_usb(f);
2326 struct ffs_data *ffs = func->ffs;
2327 unsigned long flags;
2328 int ret;
2329
2330 ENTER();
2331
2332 FVDBG("creq->bRequestType = %02x", creq->bRequestType);
2333 FVDBG("creq->bRequest = %02x", creq->bRequest);
2334 FVDBG("creq->wValue = %04x", le16_to_cpu(creq->wValue));
2335 FVDBG("creq->wIndex = %04x", le16_to_cpu(creq->wIndex));
2336 FVDBG("creq->wLength = %04x", le16_to_cpu(creq->wLength));
2337
2338 /* Most requests directed to interface go throught here
2339 * (notable exceptions are set/get interface) so we need to
2340 * handle them. All other either handled by composite or
2341 * passed to usb_configuration->setup() (if one is set). No
2342 * matter, we will handle requests directed to endpoint here
2343 * as well (as it's straightforward) but what to do with any
2344 * other request? */
2345
2346 if (ffs->state != FFS_ACTIVE)
2347 return -ENODEV;
2348
2349 switch (creq->bRequestType & USB_RECIP_MASK) {
2350 case USB_RECIP_INTERFACE:
2351 ret = ffs_func_revmap_intf(func, le16_to_cpu(creq->wIndex));
2352 if (unlikely(ret < 0))
2353 return ret;
2354 break;
2355
2356 case USB_RECIP_ENDPOINT:
2357 ret = ffs_func_revmap_ep(func, le16_to_cpu(creq->wIndex));
2358 if (unlikely(ret < 0))
2359 return ret;
2360 break;
2361
2362 default:
2363 return -EOPNOTSUPP;
2364 }
2365
2366 spin_lock_irqsave(&ffs->ev.waitq.lock, flags);
2367 ffs->ev.setup = *creq;
2368 ffs->ev.setup.wIndex = cpu_to_le16(ret);
2369 __ffs_event_add(ffs, FUNCTIONFS_SETUP);
2370 spin_unlock_irqrestore(&ffs->ev.waitq.lock, flags);
2371
2372 return 0;
2373}
2374
2375static void ffs_func_suspend(struct usb_function *f)
2376{
2377 ENTER();
2378 ffs_event_add(ffs_func_from_usb(f)->ffs, FUNCTIONFS_SUSPEND);
2379}
2380
2381static void ffs_func_resume(struct usb_function *f)
2382{
2383 ENTER();
2384 ffs_event_add(ffs_func_from_usb(f)->ffs, FUNCTIONFS_RESUME);
2385}
2386
2387
2388
2389/* Enpoint and interface numbers reverse mapping ****************************/
2390
2391static int ffs_func_revmap_ep(struct ffs_function *func, u8 num)
2392{
2393 num = func->eps_revmap[num & USB_ENDPOINT_NUMBER_MASK];
2394 return num ? num : -EDOM;
2395}
2396
2397static int ffs_func_revmap_intf(struct ffs_function *func, u8 intf)
2398{
2399 short *nums = func->interfaces_nums;
2400 unsigned count = func->ffs->interfaces_count;
2401
2402 for (; count; --count, ++nums) {
2403 if (*nums >= 0 && *nums == intf)
2404 return nums - func->interfaces_nums;
2405 }
2406
2407 return -EDOM;
2408}
2409
2410
2411/* Misc helper functions ****************************************************/
2412
2413static int ffs_mutex_lock(struct mutex *mutex, unsigned nonblock)
2414{
2415 return nonblock
2416 ? likely(mutex_trylock(mutex)) ? 0 : -EAGAIN
2417 : mutex_lock_interruptible(mutex);
2418}
2419
2420
2421static char *ffs_prepare_buffer(const char * __user buf, size_t len)
2422{
2423 char *data;
2424
2425 if (unlikely(!len))
2426 return NULL;
2427
2428 data = kmalloc(len, GFP_KERNEL);
2429 if (unlikely(!data))
2430 return ERR_PTR(-ENOMEM);
2431
2432 if (unlikely(__copy_from_user(data, buf, len))) {
2433 kfree(data);
2434 return ERR_PTR(-EFAULT);
2435 }
2436
2437 FVDBG("Buffer from user space:");
2438 ffs_dump_mem("", data, len);
2439
2440 return data;
2441}
diff --git a/include/linux/usb/functionfs.h b/include/linux/usb/functionfs.h
new file mode 100644
index 000000000000..a34a2a043b21
--- /dev/null
+++ b/include/linux/usb/functionfs.h
@@ -0,0 +1,199 @@
1#ifndef __LINUX_FUNCTIONFS_H__
2#define __LINUX_FUNCTIONFS_H__ 1
3
4
5#include <linux/types.h>
6#include <linux/ioctl.h>
7
8#include <linux/usb/ch9.h>
9
10
11enum {
12 FUNCTIONFS_DESCRIPTORS_MAGIC = 1,
13 FUNCTIONFS_STRINGS_MAGIC = 2
14};
15
16
17#ifndef __KERNEL__
18
19/* Descriptor of an non-audio endpoint */
20struct usb_endpoint_descriptor_no_audio {
21 __u8 bLength;
22 __u8 bDescriptorType;
23
24 __u8 bEndpointAddress;
25 __u8 bmAttributes;
26 __le16 wMaxPacketSize;
27 __u8 bInterval;
28} __attribute__((packed));
29
30
31/*
32 * All numbers must be in little endian order.
33 */
34
35struct usb_functionfs_descs_head {
36 __le32 magic;
37 __le32 length;
38 __le32 fs_count;
39 __le32 hs_count;
40} __attribute__((packed));
41
42/*
43 * Descriptors format:
44 *
45 * | off | name | type | description |
46 * |-----+-----------+--------------+--------------------------------------|
47 * | 0 | magic | LE32 | FUNCTIONFS_{FS,HS}_DESCRIPTORS_MAGIC |
48 * | 4 | lenght | LE32 | length of the whole data chunk |
49 * | 8 | fs_count | LE32 | number of full-speed descriptors |
50 * | 12 | hs_count | LE32 | number of high-speed descriptors |
51 * | 16 | fs_descrs | Descriptor[] | list of full-speed descriptors |
52 * | | hs_descrs | Descriptor[] | list of high-speed descriptors |
53 *
54 * descs are just valid USB descriptors and have the following format:
55 *
56 * | off | name | type | description |
57 * |-----+-----------------+------+--------------------------|
58 * | 0 | bLength | U8 | length of the descriptor |
59 * | 1 | bDescriptorType | U8 | descriptor type |
60 * | 2 | payload | | descriptor's payload |
61 */
62
63struct usb_functionfs_strings_head {
64 __le32 magic;
65 __le32 length;
66 __le32 str_count;
67 __le32 lang_count;
68} __attribute__((packed));
69
70/*
71 * Strings format:
72 *
73 * | off | name | type | description |
74 * |-----+------------+-----------------------+----------------------------|
75 * | 0 | magic | LE32 | FUNCTIONFS_STRINGS_MAGIC |
76 * | 4 | length | LE32 | length of the data chunk |
77 * | 8 | str_count | LE32 | number of strings |
78 * | 12 | lang_count | LE32 | number of languages |
79 * | 16 | stringtab | StringTab[lang_count] | table of strings per lang |
80 *
81 * For each language there is one stringtab entry (ie. there are lang_count
82 * stringtab entires). Each StringTab has following format:
83 *
84 * | off | name | type | description |
85 * |-----+---------+-------------------+------------------------------------|
86 * | 0 | lang | LE16 | language code |
87 * | 2 | strings | String[str_count] | array of strings in given language |
88 *
89 * For each string ther is one strings entry (ie. there are str_count
90 * string entries). Each String is a NUL terminated string encoded in
91 * UTF-8.
92 */
93
94#endif
95
96
97/*
98 * Events are delivered on the ep0 file descriptor, when the user mode driver
99 * reads from this file descriptor after writing the descriptors. Don't
100 * stop polling this descriptor.
101 */
102
103enum usb_functionfs_event_type {
104 FUNCTIONFS_BIND,
105 FUNCTIONFS_UNBIND,
106
107 FUNCTIONFS_ENABLE,
108 FUNCTIONFS_DISABLE,
109
110 FUNCTIONFS_SETUP,
111
112 FUNCTIONFS_SUSPEND,
113 FUNCTIONFS_RESUME
114};
115
116/* NOTE: this structure must stay the same size and layout on
117 * both 32-bit and 64-bit kernels.
118 */
119struct usb_functionfs_event {
120 union {
121 /* SETUP: packet; DATA phase i/o precedes next event
122 *(setup.bmRequestType & USB_DIR_IN) flags direction */
123 struct usb_ctrlrequest setup;
124 } __attribute__((packed)) u;
125
126 /* enum usb_functionfs_event_type */
127 __u8 type;
128 __u8 _pad[3];
129} __attribute__((packed));
130
131
132/* Endpoint ioctls */
133/* The same as in gadgetfs */
134
135/* IN transfers may be reported to the gadget driver as complete
136 * when the fifo is loaded, before the host reads the data;
137 * OUT transfers may be reported to the host's "client" driver as
138 * complete when they're sitting in the FIFO unread.
139 * THIS returns how many bytes are "unclaimed" in the endpoint fifo
140 * (needed for precise fault handling, when the hardware allows it)
141 */
142#define FUNCTIONFS_FIFO_STATUS _IO('g', 1)
143
144/* discards any unclaimed data in the fifo. */
145#define FUNCTIONFS_FIFO_FLUSH _IO('g', 2)
146
147/* resets endpoint halt+toggle; used to implement set_interface.
148 * some hardware (like pxa2xx) can't support this.
149 */
150#define FUNCTIONFS_CLEAR_HALT _IO('g', 3)
151
152/* Specific for functionfs */
153
154/*
155 * Returns reverse mapping of an interface. Called on EP0. If there
156 * is no such interface returns -EDOM. If function is not active
157 * returns -ENODEV.
158 */
159#define FUNCTIONFS_INTERFACE_REVMAP _IO('g', 128)
160
161/*
162 * Returns real bEndpointAddress of an endpoint. If function is not
163 * active returns -ENODEV.
164 */
165#define FUNCTIONFS_ENDPOINT_REVMAP _IO('g', 129)
166
167
168#ifdef __KERNEL__
169
170struct ffs_data;
171struct usb_composite_dev;
172struct usb_configuration;
173
174
175static int functionfs_init(void) __attribute__((warn_unused_result));
176static void functionfs_cleanup(void);
177
178static int functionfs_bind(struct ffs_data *ffs, struct usb_composite_dev *cdev)
179 __attribute__((warn_unused_result, nonnull));
180static void functionfs_unbind(struct ffs_data *ffs)
181 __attribute__((nonnull));
182
183static int functionfs_add(struct usb_composite_dev *cdev,
184 struct usb_configuration *c,
185 struct ffs_data *ffs)
186 __attribute__((warn_unused_result, nonnull));
187
188
189static int functionfs_ready_callback(struct ffs_data *ffs)
190 __attribute__((warn_unused_result, nonnull));
191static void functionfs_closed_callback(struct ffs_data *ffs)
192 __attribute__((nonnull));
193static int functionfs_check_dev_callback(const char *dev_name)
194 __attribute__((warn_unused_result, nonnull));
195
196
197#endif
198
199#endif
generated by cgit v1.2.2 (git 2.25.0) at 2025-10-28 01:19:38 -0400