2 * f_fs.c -- user mode file system API for USB composite function controllers
4 * Copyright (C) 2010 Samsung Electronics
5 * Author: Michal Nazarewicz <m.nazarewicz@samsung.com>
7 * Based on inode.c (GadgetFS) which was:
8 * Copyright (C) 2003-2004 David Brownell
9 * Copyright (C) 2003 Agilent Technologies
11 * This program is free software; you can redistribute it and/or modify
12 * it under the terms of the GNU General Public License as published by
13 * the Free Software Foundation; either version 2 of the License, or
14 * (at your option) any later version.
19 /* #define VERBOSE_DEBUG */
21 #include <linux/blkdev.h>
22 #include <linux/pagemap.h>
23 #include <asm/unaligned.h>
25 #include <linux/usb/composite.h>
26 #include <linux/usb/functionfs.h>
29 #define FUNCTIONFS_MAGIC 0xa647361 /* Chosen by a honest dice roll ;) */
32 /* Debugging ****************************************************************/
35 # define pr_vdebug pr_debug
36 # define ffs_dump_mem(prefix, ptr, len) \
37 print_hex_dump_bytes(pr_fmt(prefix ": "), DUMP_PREFIX_NONE, ptr, len)
39 # define pr_vdebug(...) do { } while (0)
40 # define ffs_dump_mem(prefix, ptr, len) do { } while (0)
41 #endif /* VERBOSE_DEBUG */
43 #define ENTER() pr_vdebug("%s()\n", __func__)
46 /* The data structure and setup file ****************************************/
50 * Waiting for descriptors and strings.
52 * In this state no open(2), read(2) or write(2) on epfiles
53 * may succeed (which should not be the problem as there
54 * should be no such files opened in the first place).
60 * We've got descriptors and strings. We are or have called
61 * functionfs_ready_callback(). functionfs_bind() may have
62 * been called but we don't know.
64 * This is the only state in which operations on epfiles may
70 * All endpoints have been closed. This state is also set if
71 * we encounter an unrecoverable error. The only
72 * unrecoverable error is situation when after reading strings
73 * from user space we fail to initialise epfiles or
74 * functionfs_ready_callback() returns with error (<0).
76 * In this state no open(2), read(2) or write(2) (both on ep0
77 * as well as epfile) may succeed (at this point epfiles are
78 * unlinked and all closed so this is not a problem; ep0 is
79 * also closed but ep0 file exists and so open(2) on ep0 must
86 enum ffs_setup_state {
87 /* There is no setup request pending. */
90 * User has read events and there was a setup request event
91 * there. The next read/write on ep0 will handle the
96 * There was event pending but before user space handled it
97 * some other event was introduced which canceled existing
98 * setup. If this state is set read/write on ep0 return
99 * -EIDRM. This state is only set when adding event.
110 struct usb_gadget *gadget;
113 * Protect access read/write operations, only one read/write
114 * at a time. As a consequence protects ep0req and company.
115 * While setup request is being processed (queued) this is
121 * Protect access to endpoint related structures (basically
122 * usb_ep_queue(), usb_ep_dequeue(), etc. calls) except for
128 * XXX REVISIT do we need our own request? Since we are not
129 * handling setup requests immediately user space may be so
130 * slow that another setup will be sent to the gadget but this
131 * time not to us but another function and then there could be
132 * a race. Is that the case? Or maybe we can use cdev->req
133 * after all, maybe we just need some spinlock for that?
135 struct usb_request *ep0req; /* P: mutex */
136 struct completion ep0req_completion; /* P: mutex */
137 int ep0req_status; /* P: mutex */
139 /* reference counter */
141 /* how many files are opened (EP0 and others) */
145 enum ffs_state state;
148 * Possible transitions:
149 * + FFS_NO_SETUP -> FFS_SETUP_PENDING -- P: ev.waitq.lock
150 * happens only in ep0 read which is P: mutex
151 * + FFS_SETUP_PENDING -> FFS_NO_SETUP -- P: ev.waitq.lock
152 * happens only in ep0 i/o which is P: mutex
153 * + FFS_SETUP_PENDING -> FFS_SETUP_CANCELED -- P: ev.waitq.lock
154 * + FFS_SETUP_CANCELED -> FFS_NO_SETUP -- cmpxchg
156 enum ffs_setup_state setup_state;
158 #define FFS_SETUP_STATE(ffs) \
159 ((enum ffs_setup_state)cmpxchg(&(ffs)->setup_state, \
160 FFS_SETUP_CANCELED, FFS_NO_SETUP))
165 unsigned short count;
166 /* XXX REVISIT need to update it in some places, or do we? */
167 unsigned short can_stall;
168 struct usb_ctrlrequest setup;
170 wait_queue_head_t waitq;
171 } ev; /* the whole structure, P: ev.waitq.lock */
175 #define FFS_FL_CALL_CLOSED_CALLBACK 0
176 #define FFS_FL_BOUND 1
178 /* Active function */
179 struct ffs_function *func;
182 * Device name, write once when file system is mounted.
183 * Intended for user to read if she wants.
185 const char *dev_name;
186 /* Private data for our user (ie. gadget). Managed by user. */
189 /* filled by __ffs_data_got_descs() */
191 * Real descriptors are 16 bytes after raw_descs (so you need
192 * to skip 16 bytes (ie. ffs->raw_descs + 16) to get to the
193 * first full speed descriptor). raw_descs_length and
194 * raw_fs_descs_length do not have those 16 bytes added.
196 const void *raw_descs;
197 unsigned raw_descs_length;
198 unsigned raw_fs_descs_length;
199 unsigned fs_descs_count;
200 unsigned hs_descs_count;
202 unsigned short strings_count;
203 unsigned short interfaces_count;
204 unsigned short eps_count;
205 unsigned short _pad1;
207 /* filled by __ffs_data_got_strings() */
208 /* ids in stringtabs are set in functionfs_bind() */
209 const void *raw_strings;
210 struct usb_gadget_strings **stringtabs;
213 * File system's super block, write once when file system is
216 struct super_block *sb;
218 /* File permissions, written once when fs is mounted */
219 struct ffs_file_perms {
226 * The endpoint files, filled by ffs_epfiles_create(),
227 * destroyed by ffs_epfiles_destroy().
229 struct ffs_epfile *epfiles;
232 /* Reference counter handling */
233 static void ffs_data_get(struct ffs_data *ffs);
234 static void ffs_data_put(struct ffs_data *ffs);
235 /* Creates new ffs_data object. */
236 static struct ffs_data *__must_check ffs_data_new(void) __attribute__((malloc));
238 /* Opened counter handling. */
239 static void ffs_data_opened(struct ffs_data *ffs);
240 static void ffs_data_closed(struct ffs_data *ffs);
242 /* Called with ffs->mutex held; take over ownership of data. */
243 static int __must_check
244 __ffs_data_got_descs(struct ffs_data *ffs, char *data, size_t len);
245 static int __must_check
246 __ffs_data_got_strings(struct ffs_data *ffs, char *data, size_t len);
249 /* The function structure ***************************************************/
253 struct ffs_function {
254 struct usb_configuration *conf;
255 struct usb_gadget *gadget;
256 struct ffs_data *ffs;
260 short *interfaces_nums;
262 struct usb_function function;
266 static struct ffs_function *ffs_func_from_usb(struct usb_function *f)
268 return container_of(f, struct ffs_function, function);
271 static void ffs_func_free(struct ffs_function *func);
273 static void ffs_func_eps_disable(struct ffs_function *func);
274 static int __must_check ffs_func_eps_enable(struct ffs_function *func);
276 static int ffs_func_bind(struct usb_configuration *,
277 struct usb_function *);
278 static void ffs_func_unbind(struct usb_configuration *,
279 struct usb_function *);
280 static int ffs_func_set_alt(struct usb_function *, unsigned, unsigned);
281 static void ffs_func_disable(struct usb_function *);
282 static int ffs_func_setup(struct usb_function *,
283 const struct usb_ctrlrequest *);
284 static void ffs_func_suspend(struct usb_function *);
285 static void ffs_func_resume(struct usb_function *);
288 static int ffs_func_revmap_ep(struct ffs_function *func, u8 num);
289 static int ffs_func_revmap_intf(struct ffs_function *func, u8 intf);
292 /* The endpoints structures *************************************************/
295 struct usb_ep *ep; /* P: ffs->eps_lock */
296 struct usb_request *req; /* P: epfile->mutex */
298 /* [0]: full speed, [1]: high speed */
299 struct usb_endpoint_descriptor *descs[2];
303 int status; /* P: epfile->mutex */
307 /* Protects ep->ep and ep->req. */
309 wait_queue_head_t wait;
311 struct ffs_data *ffs;
312 struct ffs_ep *ep; /* P: ffs->eps_lock */
314 struct dentry *dentry;
318 unsigned char in; /* P: ffs->eps_lock */
319 unsigned char isoc; /* P: ffs->eps_lock */
324 static int __must_check ffs_epfiles_create(struct ffs_data *ffs);
325 static void ffs_epfiles_destroy(struct ffs_epfile *epfiles, unsigned count);
327 static struct inode *__must_check
328 ffs_sb_create_file(struct super_block *sb, const char *name, void *data,
329 const struct file_operations *fops,
330 struct dentry **dentry_p);
333 /* Misc helper functions ****************************************************/
335 static int ffs_mutex_lock(struct mutex *mutex, unsigned nonblock)
336 __attribute__((warn_unused_result, nonnull));
337 static char *ffs_prepare_buffer(const char * __user buf, size_t len)
338 __attribute__((warn_unused_result, nonnull));
341 /* Control file aka ep0 *****************************************************/
343 static void ffs_ep0_complete(struct usb_ep *ep, struct usb_request *req)
345 struct ffs_data *ffs = req->context;
347 complete_all(&ffs->ep0req_completion);
350 static int __ffs_ep0_queue_wait(struct ffs_data *ffs, char *data, size_t len)
352 struct usb_request *req = ffs->ep0req;
355 req->zero = len < le16_to_cpu(ffs->ev.setup.wLength);
357 spin_unlock_irq(&ffs->ev.waitq.lock);
363 * UDC layer requires to provide a buffer even for ZLP, but should
364 * not use it at all. Let's provide some poisoned pointer to catch
365 * possible bug in the driver.
367 if (req->buf == NULL)
368 req->buf = (void *)0xDEADBABE;
370 INIT_COMPLETION(ffs->ep0req_completion);
372 ret = usb_ep_queue(ffs->gadget->ep0, req, GFP_ATOMIC);
373 if (unlikely(ret < 0))
376 ret = wait_for_completion_interruptible(&ffs->ep0req_completion);
378 usb_ep_dequeue(ffs->gadget->ep0, req);
382 ffs->setup_state = FFS_NO_SETUP;
383 return ffs->ep0req_status;
386 static int __ffs_ep0_stall(struct ffs_data *ffs)
388 if (ffs->ev.can_stall) {
389 pr_vdebug("ep0 stall\n");
390 usb_ep_set_halt(ffs->gadget->ep0);
391 ffs->setup_state = FFS_NO_SETUP;
394 pr_debug("bogus ep0 stall!\n");
399 static ssize_t ffs_ep0_write(struct file *file, const char __user *buf,
400 size_t len, loff_t *ptr)
402 struct ffs_data *ffs = file->private_data;
408 /* Fast check if setup was canceled */
409 if (FFS_SETUP_STATE(ffs) == FFS_SETUP_CANCELED)
413 ret = ffs_mutex_lock(&ffs->mutex, file->f_flags & O_NONBLOCK);
414 if (unlikely(ret < 0))
418 switch (ffs->state) {
419 case FFS_READ_DESCRIPTORS:
420 case FFS_READ_STRINGS:
422 if (unlikely(len < 16)) {
427 data = ffs_prepare_buffer(buf, len);
434 if (ffs->state == FFS_READ_DESCRIPTORS) {
435 pr_info("read descriptors\n");
436 ret = __ffs_data_got_descs(ffs, data, len);
437 if (unlikely(ret < 0))
440 ffs->state = FFS_READ_STRINGS;
443 pr_info("read strings\n");
444 ret = __ffs_data_got_strings(ffs, data, len);
445 if (unlikely(ret < 0))
448 ret = ffs_epfiles_create(ffs);
450 ffs->state = FFS_CLOSING;
454 ffs->state = FFS_ACTIVE;
455 mutex_unlock(&ffs->mutex);
457 ret = functionfs_ready_callback(ffs);
458 if (unlikely(ret < 0)) {
459 ffs->state = FFS_CLOSING;
463 set_bit(FFS_FL_CALL_CLOSED_CALLBACK, &ffs->flags);
471 * We're called from user space, we can use _irq
472 * rather then _irqsave
474 spin_lock_irq(&ffs->ev.waitq.lock);
475 switch (FFS_SETUP_STATE(ffs)) {
476 case FFS_SETUP_CANCELED:
484 case FFS_SETUP_PENDING:
488 /* FFS_SETUP_PENDING */
489 if (!(ffs->ev.setup.bRequestType & USB_DIR_IN)) {
490 spin_unlock_irq(&ffs->ev.waitq.lock);
491 ret = __ffs_ep0_stall(ffs);
495 /* FFS_SETUP_PENDING and not stall */
496 len = min(len, (size_t)le16_to_cpu(ffs->ev.setup.wLength));
498 spin_unlock_irq(&ffs->ev.waitq.lock);
500 data = ffs_prepare_buffer(buf, len);
506 spin_lock_irq(&ffs->ev.waitq.lock);
509 * We are guaranteed to be still in FFS_ACTIVE state
510 * but the state of setup could have changed from
511 * FFS_SETUP_PENDING to FFS_SETUP_CANCELED so we need
512 * to check for that. If that happened we copied data
513 * from user space in vain but it's unlikely.
515 * For sure we are not in FFS_NO_SETUP since this is
516 * the only place FFS_SETUP_PENDING -> FFS_NO_SETUP
517 * transition can be performed and it's protected by
520 if (FFS_SETUP_STATE(ffs) == FFS_SETUP_CANCELED) {
523 spin_unlock_irq(&ffs->ev.waitq.lock);
525 /* unlocks spinlock */
526 ret = __ffs_ep0_queue_wait(ffs, data, len);
536 mutex_unlock(&ffs->mutex);
540 static ssize_t __ffs_ep0_read_events(struct ffs_data *ffs, char __user *buf,
544 * We are holding ffs->ev.waitq.lock and ffs->mutex and we need
547 struct usb_functionfs_event events[n];
550 memset(events, 0, sizeof events);
553 events[i].type = ffs->ev.types[i];
554 if (events[i].type == FUNCTIONFS_SETUP) {
555 events[i].u.setup = ffs->ev.setup;
556 ffs->setup_state = FFS_SETUP_PENDING;
560 if (n < ffs->ev.count) {
562 memmove(ffs->ev.types, ffs->ev.types + n,
563 ffs->ev.count * sizeof *ffs->ev.types);
568 spin_unlock_irq(&ffs->ev.waitq.lock);
569 mutex_unlock(&ffs->mutex);
571 return unlikely(__copy_to_user(buf, events, sizeof events))
572 ? -EFAULT : sizeof events;
575 static ssize_t ffs_ep0_read(struct file *file, char __user *buf,
576 size_t len, loff_t *ptr)
578 struct ffs_data *ffs = file->private_data;
585 /* Fast check if setup was canceled */
586 if (FFS_SETUP_STATE(ffs) == FFS_SETUP_CANCELED)
590 ret = ffs_mutex_lock(&ffs->mutex, file->f_flags & O_NONBLOCK);
591 if (unlikely(ret < 0))
595 if (ffs->state != FFS_ACTIVE) {
601 * We're called from user space, we can use _irq rather then
604 spin_lock_irq(&ffs->ev.waitq.lock);
606 switch (FFS_SETUP_STATE(ffs)) {
607 case FFS_SETUP_CANCELED:
612 n = len / sizeof(struct usb_functionfs_event);
618 if ((file->f_flags & O_NONBLOCK) && !ffs->ev.count) {
623 if (wait_event_interruptible_exclusive_locked_irq(ffs->ev.waitq,
629 return __ffs_ep0_read_events(ffs, buf,
630 min(n, (size_t)ffs->ev.count));
632 case FFS_SETUP_PENDING:
633 if (ffs->ev.setup.bRequestType & USB_DIR_IN) {
634 spin_unlock_irq(&ffs->ev.waitq.lock);
635 ret = __ffs_ep0_stall(ffs);
639 len = min(len, (size_t)le16_to_cpu(ffs->ev.setup.wLength));
641 spin_unlock_irq(&ffs->ev.waitq.lock);
644 data = kmalloc(len, GFP_KERNEL);
645 if (unlikely(!data)) {
651 spin_lock_irq(&ffs->ev.waitq.lock);
653 /* See ffs_ep0_write() */
654 if (FFS_SETUP_STATE(ffs) == FFS_SETUP_CANCELED) {
659 /* unlocks spinlock */
660 ret = __ffs_ep0_queue_wait(ffs, data, len);
661 if (likely(ret > 0) && unlikely(__copy_to_user(buf, data, len)))
670 spin_unlock_irq(&ffs->ev.waitq.lock);
672 mutex_unlock(&ffs->mutex);
677 static int ffs_ep0_open(struct inode *inode, struct file *file)
679 struct ffs_data *ffs = inode->i_private;
683 if (unlikely(ffs->state == FFS_CLOSING))
686 file->private_data = ffs;
687 ffs_data_opened(ffs);
692 static int ffs_ep0_release(struct inode *inode, struct file *file)
694 struct ffs_data *ffs = file->private_data;
698 ffs_data_closed(ffs);
703 static long ffs_ep0_ioctl(struct file *file, unsigned code, unsigned long value)
705 struct ffs_data *ffs = file->private_data;
706 struct usb_gadget *gadget = ffs->gadget;
711 if (code == FUNCTIONFS_INTERFACE_REVMAP) {
712 struct ffs_function *func = ffs->func;
713 ret = func ? ffs_func_revmap_intf(func, value) : -ENODEV;
714 } else if (gadget->ops->ioctl) {
715 ret = gadget->ops->ioctl(gadget, code, value);
723 static const struct file_operations ffs_ep0_operations = {
724 .owner = THIS_MODULE,
727 .open = ffs_ep0_open,
728 .write = ffs_ep0_write,
729 .read = ffs_ep0_read,
730 .release = ffs_ep0_release,
731 .unlocked_ioctl = ffs_ep0_ioctl,
735 /* "Normal" endpoints operations ********************************************/
737 static void ffs_epfile_io_complete(struct usb_ep *_ep, struct usb_request *req)
740 if (likely(req->context)) {
741 struct ffs_ep *ep = _ep->driver_data;
742 ep->status = req->status ? req->status : req->actual;
743 complete(req->context);
747 static ssize_t ffs_epfile_io(struct file *file,
748 char __user *buf, size_t len, int read)
750 struct ffs_epfile *epfile = file->private_data;
758 spin_unlock_irq(&epfile->ffs->eps_lock);
759 mutex_unlock(&epfile->mutex);
762 /* Are we still active? */
763 if (WARN_ON(epfile->ffs->state != FFS_ACTIVE)) {
768 /* Wait for endpoint to be enabled */
771 if (file->f_flags & O_NONBLOCK) {
776 if (wait_event_interruptible(epfile->wait,
777 (ep = epfile->ep))) {
784 halt = !read == !epfile->in;
785 if (halt && epfile->isoc) {
790 /* Allocate & copy */
791 if (!halt && !data) {
792 data = kzalloc(len, GFP_KERNEL);
797 unlikely(__copy_from_user(data, buf, len))) {
803 /* We will be using request */
804 ret = ffs_mutex_lock(&epfile->mutex,
805 file->f_flags & O_NONBLOCK);
810 * We're called from user space, we can use _irq rather then
813 spin_lock_irq(&epfile->ffs->eps_lock);
816 * While we were acquiring mutex endpoint got disabled
819 } while (unlikely(epfile->ep != ep));
822 if (unlikely(halt)) {
823 if (likely(epfile->ep == ep) && !WARN_ON(!ep->ep))
824 usb_ep_set_halt(ep->ep);
825 spin_unlock_irq(&epfile->ffs->eps_lock);
828 /* Fire the request */
829 DECLARE_COMPLETION_ONSTACK(done);
831 struct usb_request *req = ep->req;
832 req->context = &done;
833 req->complete = ffs_epfile_io_complete;
837 ret = usb_ep_queue(ep->ep, req, GFP_ATOMIC);
839 spin_unlock_irq(&epfile->ffs->eps_lock);
841 if (unlikely(ret < 0)) {
843 } else if (unlikely(wait_for_completion_interruptible(&done))) {
845 usb_ep_dequeue(ep->ep, req);
848 if (read && ret > 0 &&
849 unlikely(copy_to_user(buf, data, ret)))
854 mutex_unlock(&epfile->mutex);
861 ffs_epfile_write(struct file *file, const char __user *buf, size_t len,
866 return ffs_epfile_io(file, (char __user *)buf, len, 0);
870 ffs_epfile_read(struct file *file, char __user *buf, size_t len, loff_t *ptr)
874 return ffs_epfile_io(file, buf, len, 1);
878 ffs_epfile_open(struct inode *inode, struct file *file)
880 struct ffs_epfile *epfile = inode->i_private;
884 if (WARN_ON(epfile->ffs->state != FFS_ACTIVE))
887 file->private_data = epfile;
888 ffs_data_opened(epfile->ffs);
894 ffs_epfile_release(struct inode *inode, struct file *file)
896 struct ffs_epfile *epfile = inode->i_private;
900 ffs_data_closed(epfile->ffs);
905 static long ffs_epfile_ioctl(struct file *file, unsigned code,
908 struct ffs_epfile *epfile = file->private_data;
913 if (WARN_ON(epfile->ffs->state != FFS_ACTIVE))
916 spin_lock_irq(&epfile->ffs->eps_lock);
917 if (likely(epfile->ep)) {
919 case FUNCTIONFS_FIFO_STATUS:
920 ret = usb_ep_fifo_status(epfile->ep->ep);
922 case FUNCTIONFS_FIFO_FLUSH:
923 usb_ep_fifo_flush(epfile->ep->ep);
926 case FUNCTIONFS_CLEAR_HALT:
927 ret = usb_ep_clear_halt(epfile->ep->ep);
929 case FUNCTIONFS_ENDPOINT_REVMAP:
930 ret = epfile->ep->num;
938 spin_unlock_irq(&epfile->ffs->eps_lock);
943 static const struct file_operations ffs_epfile_operations = {
944 .owner = THIS_MODULE,
947 .open = ffs_epfile_open,
948 .write = ffs_epfile_write,
949 .read = ffs_epfile_read,
950 .release = ffs_epfile_release,
951 .unlocked_ioctl = ffs_epfile_ioctl,
955 /* File system and super block operations ***********************************/
958 * Mounting the file system creates a controller file, used first for
959 * function configuration then later for event monitoring.
962 static struct inode *__must_check
963 ffs_sb_make_inode(struct super_block *sb, void *data,
964 const struct file_operations *fops,
965 const struct inode_operations *iops,
966 struct ffs_file_perms *perms)
972 inode = new_inode(sb);
975 struct timespec current_time = CURRENT_TIME;
977 inode->i_ino = get_next_ino();
978 inode->i_mode = perms->mode;
979 inode->i_uid = perms->uid;
980 inode->i_gid = perms->gid;
981 inode->i_atime = current_time;
982 inode->i_mtime = current_time;
983 inode->i_ctime = current_time;
984 inode->i_private = data;
994 /* Create "regular" file */
995 static struct inode *ffs_sb_create_file(struct super_block *sb,
996 const char *name, void *data,
997 const struct file_operations *fops,
998 struct dentry **dentry_p)
1000 struct ffs_data *ffs = sb->s_fs_info;
1001 struct dentry *dentry;
1002 struct inode *inode;
1006 dentry = d_alloc_name(sb->s_root, name);
1007 if (unlikely(!dentry))
1010 inode = ffs_sb_make_inode(sb, data, fops, NULL, &ffs->file_perms);
1011 if (unlikely(!inode)) {
1016 d_add(dentry, inode);
1024 static const struct super_operations ffs_sb_operations = {
1025 .statfs = simple_statfs,
1026 .drop_inode = generic_delete_inode,
1029 struct ffs_sb_fill_data {
1030 struct ffs_file_perms perms;
1032 const char *dev_name;
1035 static int ffs_sb_fill(struct super_block *sb, void *_data, int silent)
1037 struct ffs_sb_fill_data *data = _data;
1038 struct inode *inode;
1040 struct ffs_data *ffs;
1044 /* Initialise data */
1045 ffs = ffs_data_new();
1050 ffs->dev_name = data->dev_name;
1051 ffs->file_perms = data->perms;
1053 sb->s_fs_info = ffs;
1054 sb->s_blocksize = PAGE_CACHE_SIZE;
1055 sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
1056 sb->s_magic = FUNCTIONFS_MAGIC;
1057 sb->s_op = &ffs_sb_operations;
1058 sb->s_time_gran = 1;
1061 data->perms.mode = data->root_mode;
1062 inode = ffs_sb_make_inode(sb, NULL,
1063 &simple_dir_operations,
1064 &simple_dir_inode_operations,
1066 if (unlikely(!inode))
1068 d = d_alloc_root(inode);
1074 if (unlikely(!ffs_sb_create_file(sb, "ep0", ffs,
1075 &ffs_ep0_operations, NULL)))
1090 static int ffs_fs_parse_opts(struct ffs_sb_fill_data *data, char *opts)
1094 if (!opts || !*opts)
1098 char *end, *eq, *comma;
1099 unsigned long value;
1102 comma = strchr(opts, ',');
1107 eq = strchr(opts, '=');
1108 if (unlikely(!eq)) {
1109 pr_err("'=' missing in %s\n", opts);
1115 value = simple_strtoul(eq + 1, &end, 0);
1116 if (unlikely(*end != ',' && *end != 0)) {
1117 pr_err("%s: invalid value: %s\n", opts, eq + 1);
1121 /* Interpret option */
1122 switch (eq - opts) {
1124 if (!memcmp(opts, "rmode", 5))
1125 data->root_mode = (value & 0555) | S_IFDIR;
1126 else if (!memcmp(opts, "fmode", 5))
1127 data->perms.mode = (value & 0666) | S_IFREG;
1133 if (!memcmp(opts, "mode", 4)) {
1134 data->root_mode = (value & 0555) | S_IFDIR;
1135 data->perms.mode = (value & 0666) | S_IFREG;
1142 if (!memcmp(opts, "uid", 3))
1143 data->perms.uid = value;
1144 else if (!memcmp(opts, "gid", 3))
1145 data->perms.gid = value;
1152 pr_err("%s: invalid option\n", opts);
1156 /* Next iteration */
1165 /* "mount -t functionfs dev_name /dev/function" ends up here */
1167 static struct dentry *
1168 ffs_fs_mount(struct file_system_type *t, int flags,
1169 const char *dev_name, void *opts)
1171 struct ffs_sb_fill_data data = {
1173 .mode = S_IFREG | 0600,
1177 .root_mode = S_IFDIR | 0500,
1183 ret = functionfs_check_dev_callback(dev_name);
1184 if (unlikely(ret < 0))
1185 return ERR_PTR(ret);
1187 ret = ffs_fs_parse_opts(&data, opts);
1188 if (unlikely(ret < 0))
1189 return ERR_PTR(ret);
1191 data.dev_name = dev_name;
1192 return mount_single(t, flags, &data, ffs_sb_fill);
1196 ffs_fs_kill_sb(struct super_block *sb)
1202 kill_litter_super(sb);
1203 ptr = xchg(&sb->s_fs_info, NULL);
1208 static struct file_system_type ffs_fs_type = {
1209 .owner = THIS_MODULE,
1210 .name = "functionfs",
1211 .mount = ffs_fs_mount,
1212 .kill_sb = ffs_fs_kill_sb,
1216 /* Driver's main init/cleanup functions *************************************/
1218 static int functionfs_init(void)
1224 ret = register_filesystem(&ffs_fs_type);
1226 pr_info("file system registered\n");
1228 pr_err("failed registering file system (%d)\n", ret);
1233 static void functionfs_cleanup(void)
1237 pr_info("unloading\n");
1238 unregister_filesystem(&ffs_fs_type);
1242 /* ffs_data and ffs_function construction and destruction code **************/
1244 static void ffs_data_clear(struct ffs_data *ffs);
1245 static void ffs_data_reset(struct ffs_data *ffs);
1247 static void ffs_data_get(struct ffs_data *ffs)
1251 atomic_inc(&ffs->ref);
1254 static void ffs_data_opened(struct ffs_data *ffs)
1258 atomic_inc(&ffs->ref);
1259 atomic_inc(&ffs->opened);
1262 static void ffs_data_put(struct ffs_data *ffs)
1266 if (unlikely(atomic_dec_and_test(&ffs->ref))) {
1267 pr_info("%s(): freeing\n", __func__);
1268 ffs_data_clear(ffs);
1269 BUG_ON(mutex_is_locked(&ffs->mutex) ||
1270 spin_is_locked(&ffs->ev.waitq.lock) ||
1271 waitqueue_active(&ffs->ev.waitq) ||
1272 waitqueue_active(&ffs->ep0req_completion.wait));
1277 static void ffs_data_closed(struct ffs_data *ffs)
1281 if (atomic_dec_and_test(&ffs->opened)) {
1282 ffs->state = FFS_CLOSING;
1283 ffs_data_reset(ffs);
1289 static struct ffs_data *ffs_data_new(void)
1291 struct ffs_data *ffs = kzalloc(sizeof *ffs, GFP_KERNEL);
1297 atomic_set(&ffs->ref, 1);
1298 atomic_set(&ffs->opened, 0);
1299 ffs->state = FFS_READ_DESCRIPTORS;
1300 mutex_init(&ffs->mutex);
1301 spin_lock_init(&ffs->eps_lock);
1302 init_waitqueue_head(&ffs->ev.waitq);
1303 init_completion(&ffs->ep0req_completion);
1305 /* XXX REVISIT need to update it in some places, or do we? */
1306 ffs->ev.can_stall = 1;
1311 static void ffs_data_clear(struct ffs_data *ffs)
1315 if (test_and_clear_bit(FFS_FL_CALL_CLOSED_CALLBACK, &ffs->flags))
1316 functionfs_closed_callback(ffs);
1318 BUG_ON(ffs->gadget);
1321 ffs_epfiles_destroy(ffs->epfiles, ffs->eps_count);
1323 kfree(ffs->raw_descs);
1324 kfree(ffs->raw_strings);
1325 kfree(ffs->stringtabs);
1328 static void ffs_data_reset(struct ffs_data *ffs)
1332 ffs_data_clear(ffs);
1334 ffs->epfiles = NULL;
1335 ffs->raw_descs = NULL;
1336 ffs->raw_strings = NULL;
1337 ffs->stringtabs = NULL;
1339 ffs->raw_descs_length = 0;
1340 ffs->raw_fs_descs_length = 0;
1341 ffs->fs_descs_count = 0;
1342 ffs->hs_descs_count = 0;
1344 ffs->strings_count = 0;
1345 ffs->interfaces_count = 0;
1350 ffs->state = FFS_READ_DESCRIPTORS;
1351 ffs->setup_state = FFS_NO_SETUP;
1356 static int functionfs_bind(struct ffs_data *ffs, struct usb_composite_dev *cdev)
1358 struct usb_gadget_strings **lang;
1363 if (WARN_ON(ffs->state != FFS_ACTIVE
1364 || test_and_set_bit(FFS_FL_BOUND, &ffs->flags)))
1367 first_id = usb_string_ids_n(cdev, ffs->strings_count);
1368 if (unlikely(first_id < 0))
1371 ffs->ep0req = usb_ep_alloc_request(cdev->gadget->ep0, GFP_KERNEL);
1372 if (unlikely(!ffs->ep0req))
1374 ffs->ep0req->complete = ffs_ep0_complete;
1375 ffs->ep0req->context = ffs;
1377 lang = ffs->stringtabs;
1378 for (lang = ffs->stringtabs; *lang; ++lang) {
1379 struct usb_string *str = (*lang)->strings;
1381 for (; str->s; ++id, ++str)
1385 ffs->gadget = cdev->gadget;
1390 static void functionfs_unbind(struct ffs_data *ffs)
1394 if (!WARN_ON(!ffs->gadget)) {
1395 usb_ep_free_request(ffs->gadget->ep0, ffs->ep0req);
1402 static int ffs_epfiles_create(struct ffs_data *ffs)
1404 struct ffs_epfile *epfile, *epfiles;
1409 count = ffs->eps_count;
1410 epfiles = kzalloc(count * sizeof *epfiles, GFP_KERNEL);
1415 for (i = 1; i <= count; ++i, ++epfile) {
1417 mutex_init(&epfile->mutex);
1418 init_waitqueue_head(&epfile->wait);
1419 sprintf(epfiles->name, "ep%u", i);
1420 if (!unlikely(ffs_sb_create_file(ffs->sb, epfiles->name, epfile,
1421 &ffs_epfile_operations,
1422 &epfile->dentry))) {
1423 ffs_epfiles_destroy(epfiles, i - 1);
1428 ffs->epfiles = epfiles;
1432 static void ffs_epfiles_destroy(struct ffs_epfile *epfiles, unsigned count)
1434 struct ffs_epfile *epfile = epfiles;
1438 for (; count; --count, ++epfile) {
1439 BUG_ON(mutex_is_locked(&epfile->mutex) ||
1440 waitqueue_active(&epfile->wait));
1441 if (epfile->dentry) {
1442 d_delete(epfile->dentry);
1443 dput(epfile->dentry);
1444 epfile->dentry = NULL;
1451 static int functionfs_bind_config(struct usb_composite_dev *cdev,
1452 struct usb_configuration *c,
1453 struct ffs_data *ffs)
1455 struct ffs_function *func;
1460 func = kzalloc(sizeof *func, GFP_KERNEL);
1461 if (unlikely(!func))
1464 func->function.name = "Function FS Gadget";
1465 func->function.strings = ffs->stringtabs;
1467 func->function.bind = ffs_func_bind;
1468 func->function.unbind = ffs_func_unbind;
1469 func->function.set_alt = ffs_func_set_alt;
1470 func->function.disable = ffs_func_disable;
1471 func->function.setup = ffs_func_setup;
1472 func->function.suspend = ffs_func_suspend;
1473 func->function.resume = ffs_func_resume;
1476 func->gadget = cdev->gadget;
1480 ret = usb_add_function(c, &func->function);
1482 ffs_func_free(func);
1487 static void ffs_func_free(struct ffs_function *func)
1491 ffs_data_put(func->ffs);
1495 * eps and interfaces_nums are allocated in the same chunk so
1496 * only one free is required. Descriptors are also allocated
1497 * in the same chunk.
1503 static void ffs_func_eps_disable(struct ffs_function *func)
1505 struct ffs_ep *ep = func->eps;
1506 struct ffs_epfile *epfile = func->ffs->epfiles;
1507 unsigned count = func->ffs->eps_count;
1508 unsigned long flags;
1510 spin_lock_irqsave(&func->ffs->eps_lock, flags);
1512 /* pending requests get nuked */
1514 usb_ep_disable(ep->ep);
1520 spin_unlock_irqrestore(&func->ffs->eps_lock, flags);
1523 static int ffs_func_eps_enable(struct ffs_function *func)
1525 struct ffs_data *ffs = func->ffs;
1526 struct ffs_ep *ep = func->eps;
1527 struct ffs_epfile *epfile = ffs->epfiles;
1528 unsigned count = ffs->eps_count;
1529 unsigned long flags;
1532 spin_lock_irqsave(&func->ffs->eps_lock, flags);
1534 struct usb_endpoint_descriptor *ds;
1535 ds = ep->descs[ep->descs[1] ? 1 : 0];
1537 ep->ep->driver_data = ep;
1539 ret = usb_ep_enable(ep->ep);
1542 epfile->in = usb_endpoint_dir_in(ds);
1543 epfile->isoc = usb_endpoint_xfer_isoc(ds);
1548 wake_up(&epfile->wait);
1553 spin_unlock_irqrestore(&func->ffs->eps_lock, flags);
1559 /* Parsing and building descriptors and strings *****************************/
1562 * This validates if data pointed by data is a valid USB descriptor as
1563 * well as record how many interfaces, endpoints and strings are
1564 * required by given configuration. Returns address after the
1565 * descriptor or NULL if data is invalid.
1568 enum ffs_entity_type {
1569 FFS_DESCRIPTOR, FFS_INTERFACE, FFS_STRING, FFS_ENDPOINT
1572 typedef int (*ffs_entity_callback)(enum ffs_entity_type entity,
1574 struct usb_descriptor_header *desc,
1577 static int __must_check ffs_do_desc(char *data, unsigned len,
1578 ffs_entity_callback entity, void *priv)
1580 struct usb_descriptor_header *_ds = (void *)data;
1586 /* At least two bytes are required: length and type */
1588 pr_vdebug("descriptor too short\n");
1592 /* If we have at least as many bytes as the descriptor takes? */
1593 length = _ds->bLength;
1595 pr_vdebug("descriptor longer then available data\n");
1599 #define __entity_check_INTERFACE(val) 1
1600 #define __entity_check_STRING(val) (val)
1601 #define __entity_check_ENDPOINT(val) ((val) & USB_ENDPOINT_NUMBER_MASK)
1602 #define __entity(type, val) do { \
1603 pr_vdebug("entity " #type "(%02x)\n", (val)); \
1604 if (unlikely(!__entity_check_ ##type(val))) { \
1605 pr_vdebug("invalid entity's value\n"); \
1608 ret = entity(FFS_ ##type, &val, _ds, priv); \
1609 if (unlikely(ret < 0)) { \
1610 pr_debug("entity " #type "(%02x); ret = %d\n", \
1616 /* Parse descriptor depending on type. */
1617 switch (_ds->bDescriptorType) {
1621 case USB_DT_DEVICE_QUALIFIER:
1622 /* function can't have any of those */
1623 pr_vdebug("descriptor reserved for gadget: %d\n",
1624 _ds->bDescriptorType);
1627 case USB_DT_INTERFACE: {
1628 struct usb_interface_descriptor *ds = (void *)_ds;
1629 pr_vdebug("interface descriptor\n");
1630 if (length != sizeof *ds)
1633 __entity(INTERFACE, ds->bInterfaceNumber);
1635 __entity(STRING, ds->iInterface);
1639 case USB_DT_ENDPOINT: {
1640 struct usb_endpoint_descriptor *ds = (void *)_ds;
1641 pr_vdebug("endpoint descriptor\n");
1642 if (length != USB_DT_ENDPOINT_SIZE &&
1643 length != USB_DT_ENDPOINT_AUDIO_SIZE)
1645 __entity(ENDPOINT, ds->bEndpointAddress);
1650 if (length != sizeof(struct usb_otg_descriptor))
1654 case USB_DT_INTERFACE_ASSOCIATION: {
1655 struct usb_interface_assoc_descriptor *ds = (void *)_ds;
1656 pr_vdebug("interface association descriptor\n");
1657 if (length != sizeof *ds)
1660 __entity(STRING, ds->iFunction);
1664 case USB_DT_OTHER_SPEED_CONFIG:
1665 case USB_DT_INTERFACE_POWER:
1667 case USB_DT_SECURITY:
1668 case USB_DT_CS_RADIO_CONTROL:
1670 pr_vdebug("unimplemented descriptor: %d\n", _ds->bDescriptorType);
1674 /* We should never be here */
1675 pr_vdebug("unknown descriptor: %d\n", _ds->bDescriptorType);
1679 pr_vdebug("invalid length: %d (descriptor %d)\n",
1680 _ds->bLength, _ds->bDescriptorType);
1685 #undef __entity_check_DESCRIPTOR
1686 #undef __entity_check_INTERFACE
1687 #undef __entity_check_STRING
1688 #undef __entity_check_ENDPOINT
1693 static int __must_check ffs_do_descs(unsigned count, char *data, unsigned len,
1694 ffs_entity_callback entity, void *priv)
1696 const unsigned _len = len;
1697 unsigned long num = 0;
1707 /* Record "descriptor" entity */
1708 ret = entity(FFS_DESCRIPTOR, (u8 *)num, (void *)data, priv);
1709 if (unlikely(ret < 0)) {
1710 pr_debug("entity DESCRIPTOR(%02lx); ret = %d\n",
1718 ret = ffs_do_desc(data, len, entity, priv);
1719 if (unlikely(ret < 0)) {
1720 pr_debug("%s returns %d\n", __func__, ret);
1730 static int __ffs_data_do_entity(enum ffs_entity_type type,
1731 u8 *valuep, struct usb_descriptor_header *desc,
1734 struct ffs_data *ffs = priv;
1739 case FFS_DESCRIPTOR:
1744 * Interfaces are indexed from zero so if we
1745 * encountered interface "n" then there are at least
1748 if (*valuep >= ffs->interfaces_count)
1749 ffs->interfaces_count = *valuep + 1;
1754 * Strings are indexed from 1 (0 is magic ;) reserved
1755 * for languages list or some such)
1757 if (*valuep > ffs->strings_count)
1758 ffs->strings_count = *valuep;
1762 /* Endpoints are indexed from 1 as well. */
1763 if ((*valuep & USB_ENDPOINT_NUMBER_MASK) > ffs->eps_count)
1764 ffs->eps_count = (*valuep & USB_ENDPOINT_NUMBER_MASK);
1771 static int __ffs_data_got_descs(struct ffs_data *ffs,
1772 char *const _data, size_t len)
1774 unsigned fs_count, hs_count;
1775 int fs_len, ret = -EINVAL;
1780 if (unlikely(get_unaligned_le32(data) != FUNCTIONFS_DESCRIPTORS_MAGIC ||
1781 get_unaligned_le32(data + 4) != len))
1783 fs_count = get_unaligned_le32(data + 8);
1784 hs_count = get_unaligned_le32(data + 12);
1786 if (!fs_count && !hs_count)
1792 if (likely(fs_count)) {
1793 fs_len = ffs_do_descs(fs_count, data, len,
1794 __ffs_data_do_entity, ffs);
1795 if (unlikely(fs_len < 0)) {
1806 if (likely(hs_count)) {
1807 ret = ffs_do_descs(hs_count, data, len,
1808 __ffs_data_do_entity, ffs);
1809 if (unlikely(ret < 0))
1815 if (unlikely(len != ret))
1818 ffs->raw_fs_descs_length = fs_len;
1819 ffs->raw_descs_length = fs_len + ret;
1820 ffs->raw_descs = _data;
1821 ffs->fs_descs_count = fs_count;
1822 ffs->hs_descs_count = hs_count;
1833 static int __ffs_data_got_strings(struct ffs_data *ffs,
1834 char *const _data, size_t len)
1836 u32 str_count, needed_count, lang_count;
1837 struct usb_gadget_strings **stringtabs, *t;
1838 struct usb_string *strings, *s;
1839 const char *data = _data;
1843 if (unlikely(get_unaligned_le32(data) != FUNCTIONFS_STRINGS_MAGIC ||
1844 get_unaligned_le32(data + 4) != len))
1846 str_count = get_unaligned_le32(data + 8);
1847 lang_count = get_unaligned_le32(data + 12);
1849 /* if one is zero the other must be zero */
1850 if (unlikely(!str_count != !lang_count))
1853 /* Do we have at least as many strings as descriptors need? */
1854 needed_count = ffs->strings_count;
1855 if (unlikely(str_count < needed_count))
1859 * If we don't need any strings just return and free all
1862 if (!needed_count) {
1867 /* Allocate everything in one chunk so there's less maintenance. */
1870 struct usb_gadget_strings *stringtabs[lang_count + 1];
1871 struct usb_gadget_strings stringtab[lang_count];
1872 struct usb_string strings[lang_count*(needed_count+1)];
1876 d = kmalloc(sizeof *d, GFP_KERNEL);
1882 stringtabs = d->stringtabs;
1886 *stringtabs++ = t++;
1890 stringtabs = d->stringtabs;
1896 /* For each language */
1900 do { /* lang_count > 0 so we can use do-while */
1901 unsigned needed = needed_count;
1903 if (unlikely(len < 3))
1905 t->language = get_unaligned_le16(data);
1912 /* For each string */
1913 do { /* str_count > 0 so we can use do-while */
1914 size_t length = strnlen(data, len);
1916 if (unlikely(length == len))
1920 * User may provide more strings then we need,
1921 * if that's the case we simply ignore the
1924 if (likely(needed)) {
1926 * s->id will be set while adding
1927 * function to configuration so for
1928 * now just leave garbage here.
1937 } while (--str_count);
1939 s->id = 0; /* terminator */
1943 } while (--lang_count);
1945 /* Some garbage left? */
1950 ffs->stringtabs = stringtabs;
1951 ffs->raw_strings = _data;
1963 /* Events handling and management *******************************************/
1965 static void __ffs_event_add(struct ffs_data *ffs,
1966 enum usb_functionfs_event_type type)
1968 enum usb_functionfs_event_type rem_type1, rem_type2 = type;
1972 * Abort any unhandled setup
1974 * We do not need to worry about some cmpxchg() changing value
1975 * of ffs->setup_state without holding the lock because when
1976 * state is FFS_SETUP_PENDING cmpxchg() in several places in
1977 * the source does nothing.
1979 if (ffs->setup_state == FFS_SETUP_PENDING)
1980 ffs->setup_state = FFS_SETUP_CANCELED;
1983 case FUNCTIONFS_RESUME:
1984 rem_type2 = FUNCTIONFS_SUSPEND;
1986 case FUNCTIONFS_SUSPEND:
1987 case FUNCTIONFS_SETUP:
1989 /* Discard all similar events */
1992 case FUNCTIONFS_BIND:
1993 case FUNCTIONFS_UNBIND:
1994 case FUNCTIONFS_DISABLE:
1995 case FUNCTIONFS_ENABLE:
1996 /* Discard everything other then power management. */
1997 rem_type1 = FUNCTIONFS_SUSPEND;
1998 rem_type2 = FUNCTIONFS_RESUME;
2007 u8 *ev = ffs->ev.types, *out = ev;
2008 unsigned n = ffs->ev.count;
2009 for (; n; --n, ++ev)
2010 if ((*ev == rem_type1 || *ev == rem_type2) == neg)
2013 pr_vdebug("purging event %d\n", *ev);
2014 ffs->ev.count = out - ffs->ev.types;
2017 pr_vdebug("adding event %d\n", type);
2018 ffs->ev.types[ffs->ev.count++] = type;
2019 wake_up_locked(&ffs->ev.waitq);
2022 static void ffs_event_add(struct ffs_data *ffs,
2023 enum usb_functionfs_event_type type)
2025 unsigned long flags;
2026 spin_lock_irqsave(&ffs->ev.waitq.lock, flags);
2027 __ffs_event_add(ffs, type);
2028 spin_unlock_irqrestore(&ffs->ev.waitq.lock, flags);
2032 /* Bind/unbind USB function hooks *******************************************/
2034 static int __ffs_func_bind_do_descs(enum ffs_entity_type type, u8 *valuep,
2035 struct usb_descriptor_header *desc,
2038 struct usb_endpoint_descriptor *ds = (void *)desc;
2039 struct ffs_function *func = priv;
2040 struct ffs_ep *ffs_ep;
2043 * If hs_descriptors is not NULL then we are reading hs
2046 const int isHS = func->function.hs_descriptors != NULL;
2049 if (type != FFS_DESCRIPTOR)
2053 func->function.hs_descriptors[(long)valuep] = desc;
2055 func->function.descriptors[(long)valuep] = desc;
2057 if (!desc || desc->bDescriptorType != USB_DT_ENDPOINT)
2060 idx = (ds->bEndpointAddress & USB_ENDPOINT_NUMBER_MASK) - 1;
2061 ffs_ep = func->eps + idx;
2063 if (unlikely(ffs_ep->descs[isHS])) {
2064 pr_vdebug("two %sspeed descriptors for EP %d\n",
2065 isHS ? "high" : "full",
2066 ds->bEndpointAddress & USB_ENDPOINT_NUMBER_MASK);
2069 ffs_ep->descs[isHS] = ds;
2071 ffs_dump_mem(": Original ep desc", ds, ds->bLength);
2073 ds->bEndpointAddress = ffs_ep->descs[0]->bEndpointAddress;
2074 if (!ds->wMaxPacketSize)
2075 ds->wMaxPacketSize = ffs_ep->descs[0]->wMaxPacketSize;
2077 struct usb_request *req;
2080 pr_vdebug("autoconfig\n");
2081 ep = usb_ep_autoconfig(func->gadget, ds);
2084 ep->driver_data = func->eps + idx;
2086 req = usb_ep_alloc_request(ep, GFP_KERNEL);
2092 func->eps_revmap[ds->bEndpointAddress &
2093 USB_ENDPOINT_NUMBER_MASK] = idx + 1;
2095 ffs_dump_mem(": Rewritten ep desc", ds, ds->bLength);
2100 static int __ffs_func_bind_do_nums(enum ffs_entity_type type, u8 *valuep,
2101 struct usb_descriptor_header *desc,
2104 struct ffs_function *func = priv;
2110 case FFS_DESCRIPTOR:
2111 /* Handled in previous pass by __ffs_func_bind_do_descs() */
2116 if (func->interfaces_nums[idx] < 0) {
2117 int id = usb_interface_id(func->conf, &func->function);
2118 if (unlikely(id < 0))
2120 func->interfaces_nums[idx] = id;
2122 newValue = func->interfaces_nums[idx];
2126 /* String' IDs are allocated when fsf_data is bound to cdev */
2127 newValue = func->ffs->stringtabs[0]->strings[*valuep - 1].id;
2132 * USB_DT_ENDPOINT are handled in
2133 * __ffs_func_bind_do_descs().
2135 if (desc->bDescriptorType == USB_DT_ENDPOINT)
2138 idx = (*valuep & USB_ENDPOINT_NUMBER_MASK) - 1;
2139 if (unlikely(!func->eps[idx].ep))
2143 struct usb_endpoint_descriptor **descs;
2144 descs = func->eps[idx].descs;
2145 newValue = descs[descs[0] ? 0 : 1]->bEndpointAddress;
2150 pr_vdebug("%02x -> %02x\n", *valuep, newValue);
2155 static int ffs_func_bind(struct usb_configuration *c,
2156 struct usb_function *f)
2158 struct ffs_function *func = ffs_func_from_usb(f);
2159 struct ffs_data *ffs = func->ffs;
2161 const int full = !!func->ffs->fs_descs_count;
2162 const int high = gadget_is_dualspeed(func->gadget) &&
2163 func->ffs->hs_descs_count;
2167 /* Make it a single chunk, less management later on */
2169 struct ffs_ep eps[ffs->eps_count];
2170 struct usb_descriptor_header
2171 *fs_descs[full ? ffs->fs_descs_count + 1 : 0];
2172 struct usb_descriptor_header
2173 *hs_descs[high ? ffs->hs_descs_count + 1 : 0];
2174 short inums[ffs->interfaces_count];
2175 char raw_descs[high ? ffs->raw_descs_length
2176 : ffs->raw_fs_descs_length];
2181 /* Only high speed but not supported by gadget? */
2182 if (unlikely(!(full | high)))
2186 data = kmalloc(sizeof *data, GFP_KERNEL);
2187 if (unlikely(!data))
2191 memset(data->eps, 0, sizeof data->eps);
2192 memcpy(data->raw_descs, ffs->raw_descs + 16, sizeof data->raw_descs);
2193 memset(data->inums, 0xff, sizeof data->inums);
2194 for (ret = ffs->eps_count; ret; --ret)
2195 data->eps[ret].num = -1;
2198 func->eps = data->eps;
2199 func->interfaces_nums = data->inums;
2202 * Go through all the endpoint descriptors and allocate
2203 * endpoints first, so that later we can rewrite the endpoint
2204 * numbers without worrying that it may be described later on.
2207 func->function.descriptors = data->fs_descs;
2208 ret = ffs_do_descs(ffs->fs_descs_count,
2210 sizeof data->raw_descs,
2211 __ffs_func_bind_do_descs, func);
2212 if (unlikely(ret < 0))
2219 func->function.hs_descriptors = data->hs_descs;
2220 ret = ffs_do_descs(ffs->hs_descs_count,
2221 data->raw_descs + ret,
2222 (sizeof data->raw_descs) - ret,
2223 __ffs_func_bind_do_descs, func);
2227 * Now handle interface numbers allocation and interface and
2228 * endpoint numbers rewriting. We can do that in one go
2231 ret = ffs_do_descs(ffs->fs_descs_count +
2232 (high ? ffs->hs_descs_count : 0),
2233 data->raw_descs, sizeof data->raw_descs,
2234 __ffs_func_bind_do_nums, func);
2235 if (unlikely(ret < 0))
2238 /* And we're done */
2239 ffs_event_add(ffs, FUNCTIONFS_BIND);
2243 /* XXX Do we need to release all claimed endpoints here? */
2248 /* Other USB function hooks *************************************************/
2250 static void ffs_func_unbind(struct usb_configuration *c,
2251 struct usb_function *f)
2253 struct ffs_function *func = ffs_func_from_usb(f);
2254 struct ffs_data *ffs = func->ffs;
2258 if (ffs->func == func) {
2259 ffs_func_eps_disable(func);
2263 ffs_event_add(ffs, FUNCTIONFS_UNBIND);
2265 ffs_func_free(func);
2268 static int ffs_func_set_alt(struct usb_function *f,
2269 unsigned interface, unsigned alt)
2271 struct ffs_function *func = ffs_func_from_usb(f);
2272 struct ffs_data *ffs = func->ffs;
2275 if (alt != (unsigned)-1) {
2276 intf = ffs_func_revmap_intf(func, interface);
2277 if (unlikely(intf < 0))
2282 ffs_func_eps_disable(ffs->func);
2284 if (ffs->state != FFS_ACTIVE)
2287 if (alt == (unsigned)-1) {
2289 ffs_event_add(ffs, FUNCTIONFS_DISABLE);
2294 ret = ffs_func_eps_enable(func);
2295 if (likely(ret >= 0))
2296 ffs_event_add(ffs, FUNCTIONFS_ENABLE);
2300 static void ffs_func_disable(struct usb_function *f)
2302 ffs_func_set_alt(f, 0, (unsigned)-1);
2305 static int ffs_func_setup(struct usb_function *f,
2306 const struct usb_ctrlrequest *creq)
2308 struct ffs_function *func = ffs_func_from_usb(f);
2309 struct ffs_data *ffs = func->ffs;
2310 unsigned long flags;
2315 pr_vdebug("creq->bRequestType = %02x\n", creq->bRequestType);
2316 pr_vdebug("creq->bRequest = %02x\n", creq->bRequest);
2317 pr_vdebug("creq->wValue = %04x\n", le16_to_cpu(creq->wValue));
2318 pr_vdebug("creq->wIndex = %04x\n", le16_to_cpu(creq->wIndex));
2319 pr_vdebug("creq->wLength = %04x\n", le16_to_cpu(creq->wLength));
2322 * Most requests directed to interface go through here
2323 * (notable exceptions are set/get interface) so we need to
2324 * handle them. All other either handled by composite or
2325 * passed to usb_configuration->setup() (if one is set). No
2326 * matter, we will handle requests directed to endpoint here
2327 * as well (as it's straightforward) but what to do with any
2330 if (ffs->state != FFS_ACTIVE)
2333 switch (creq->bRequestType & USB_RECIP_MASK) {
2334 case USB_RECIP_INTERFACE:
2335 ret = ffs_func_revmap_intf(func, le16_to_cpu(creq->wIndex));
2336 if (unlikely(ret < 0))
2340 case USB_RECIP_ENDPOINT:
2341 ret = ffs_func_revmap_ep(func, le16_to_cpu(creq->wIndex));
2342 if (unlikely(ret < 0))
2350 spin_lock_irqsave(&ffs->ev.waitq.lock, flags);
2351 ffs->ev.setup = *creq;
2352 ffs->ev.setup.wIndex = cpu_to_le16(ret);
2353 __ffs_event_add(ffs, FUNCTIONFS_SETUP);
2354 spin_unlock_irqrestore(&ffs->ev.waitq.lock, flags);
2359 static void ffs_func_suspend(struct usb_function *f)
2362 ffs_event_add(ffs_func_from_usb(f)->ffs, FUNCTIONFS_SUSPEND);
2365 static void ffs_func_resume(struct usb_function *f)
2368 ffs_event_add(ffs_func_from_usb(f)->ffs, FUNCTIONFS_RESUME);
2372 /* Endpoint and interface numbers reverse mapping ***************************/
2374 static int ffs_func_revmap_ep(struct ffs_function *func, u8 num)
2376 num = func->eps_revmap[num & USB_ENDPOINT_NUMBER_MASK];
2377 return num ? num : -EDOM;
2380 static int ffs_func_revmap_intf(struct ffs_function *func, u8 intf)
2382 short *nums = func->interfaces_nums;
2383 unsigned count = func->ffs->interfaces_count;
2385 for (; count; --count, ++nums) {
2386 if (*nums >= 0 && *nums == intf)
2387 return nums - func->interfaces_nums;
2394 /* Misc helper functions ****************************************************/
2396 static int ffs_mutex_lock(struct mutex *mutex, unsigned nonblock)
2399 ? likely(mutex_trylock(mutex)) ? 0 : -EAGAIN
2400 : mutex_lock_interruptible(mutex);
2403 static char *ffs_prepare_buffer(const char * __user buf, size_t len)
2410 data = kmalloc(len, GFP_KERNEL);
2411 if (unlikely(!data))
2412 return ERR_PTR(-ENOMEM);
2414 if (unlikely(__copy_from_user(data, buf, len))) {
2416 return ERR_PTR(-EFAULT);
2419 pr_vdebug("Buffer from user space:\n");
2420 ffs_dump_mem("", data, len);