2 * f_fs.c -- user mode file system API for USB composite function controllers
4 * Copyright (C) 2010 Samsung Electronics
5 * Author: Michal Nazarewicz <mina86@mina86.com>
7 * Based on inode.c (GadgetFS) which was:
8 * Copyright (C) 2003-2004 David Brownell
9 * Copyright (C) 2003 Agilent Technologies
11 * This program is free software; you can redistribute it and/or modify
12 * it under the terms of the GNU General Public License as published by
13 * the Free Software Foundation; either version 2 of the License, or
14 * (at your option) any later version.
19 /* #define VERBOSE_DEBUG */
21 #include <linux/blkdev.h>
22 #include <linux/pagemap.h>
23 #include <linux/export.h>
24 #include <linux/hid.h>
25 #include <linux/module.h>
26 #include <linux/uio.h>
27 #include <asm/unaligned.h>
29 #include <linux/usb/composite.h>
30 #include <linux/usb/functionfs.h>
32 #include <linux/aio.h>
33 #include <linux/mmu_context.h>
34 #include <linux/poll.h>
35 #include <linux/eventfd.h>
39 #include "u_os_desc.h"
42 #define FUNCTIONFS_MAGIC 0xa647361 /* Chosen by a honest dice roll ;) */
44 /* Reference counter handling */
45 static void ffs_data_get(struct ffs_data *ffs);
46 static void ffs_data_put(struct ffs_data *ffs);
47 /* Creates new ffs_data object. */
48 static struct ffs_data *__must_check ffs_data_new(void) __attribute__((malloc));
50 /* Opened counter handling. */
51 static void ffs_data_opened(struct ffs_data *ffs);
52 static void ffs_data_closed(struct ffs_data *ffs);
54 /* Called with ffs->mutex held; take over ownership of data. */
55 static int __must_check
56 __ffs_data_got_descs(struct ffs_data *ffs, char *data, size_t len);
57 static int __must_check
58 __ffs_data_got_strings(struct ffs_data *ffs, char *data, size_t len);
61 /* The function structure ***************************************************/
66 struct usb_configuration *conf;
67 struct usb_gadget *gadget;
72 short *interfaces_nums;
74 struct usb_function function;
78 static struct ffs_function *ffs_func_from_usb(struct usb_function *f)
80 return container_of(f, struct ffs_function, function);
84 static inline enum ffs_setup_state
85 ffs_setup_state_clear_cancelled(struct ffs_data *ffs)
87 return (enum ffs_setup_state)
88 cmpxchg(&ffs->setup_state, FFS_SETUP_CANCELLED, FFS_NO_SETUP);
92 static void ffs_func_eps_disable(struct ffs_function *func);
93 static int __must_check ffs_func_eps_enable(struct ffs_function *func);
95 static int ffs_func_bind(struct usb_configuration *,
96 struct usb_function *);
97 static int ffs_func_set_alt(struct usb_function *, unsigned, unsigned);
98 static void ffs_func_disable(struct usb_function *);
99 static int ffs_func_setup(struct usb_function *,
100 const struct usb_ctrlrequest *);
101 static void ffs_func_suspend(struct usb_function *);
102 static void ffs_func_resume(struct usb_function *);
105 static int ffs_func_revmap_ep(struct ffs_function *func, u8 num);
106 static int ffs_func_revmap_intf(struct ffs_function *func, u8 intf);
109 /* The endpoints structures *************************************************/
112 struct usb_ep *ep; /* P: ffs->eps_lock */
113 struct usb_request *req; /* P: epfile->mutex */
115 /* [0]: full speed, [1]: high speed, [2]: super speed */
116 struct usb_endpoint_descriptor *descs[3];
120 int status; /* P: epfile->mutex */
124 /* Protects ep->ep and ep->req. */
126 wait_queue_head_t wait;
128 struct ffs_data *ffs;
129 struct ffs_ep *ep; /* P: ffs->eps_lock */
131 struct dentry *dentry;
135 unsigned char in; /* P: ffs->eps_lock */
136 unsigned char isoc; /* P: ffs->eps_lock */
141 /* ffs_io_data structure ***************************************************/
148 struct iov_iter data;
152 struct mm_struct *mm;
153 struct work_struct work;
156 struct usb_request *req;
158 struct ffs_data *ffs;
161 struct ffs_desc_helper {
162 struct ffs_data *ffs;
163 unsigned interfaces_count;
167 static int __must_check ffs_epfiles_create(struct ffs_data *ffs);
168 static void ffs_epfiles_destroy(struct ffs_epfile *epfiles, unsigned count);
170 static struct dentry *
171 ffs_sb_create_file(struct super_block *sb, const char *name, void *data,
172 const struct file_operations *fops);
174 /* Devices management *******************************************************/
176 DEFINE_MUTEX(ffs_lock);
177 EXPORT_SYMBOL_GPL(ffs_lock);
179 static struct ffs_dev *_ffs_find_dev(const char *name);
180 static struct ffs_dev *_ffs_alloc_dev(void);
181 static int _ffs_name_dev(struct ffs_dev *dev, const char *name);
182 static void _ffs_free_dev(struct ffs_dev *dev);
183 static void *ffs_acquire_dev(const char *dev_name);
184 static void ffs_release_dev(struct ffs_data *ffs_data);
185 static int ffs_ready(struct ffs_data *ffs);
186 static void ffs_closed(struct ffs_data *ffs);
188 /* Misc helper functions ****************************************************/
190 static int ffs_mutex_lock(struct mutex *mutex, unsigned nonblock)
191 __attribute__((warn_unused_result, nonnull));
192 static char *ffs_prepare_buffer(const char __user *buf, size_t len)
193 __attribute__((warn_unused_result, nonnull));
196 /* Control file aka ep0 *****************************************************/
198 static void ffs_ep0_complete(struct usb_ep *ep, struct usb_request *req)
200 struct ffs_data *ffs = req->context;
202 complete_all(&ffs->ep0req_completion);
205 static int __ffs_ep0_queue_wait(struct ffs_data *ffs, char *data, size_t len)
207 struct usb_request *req = ffs->ep0req;
210 req->zero = len < le16_to_cpu(ffs->ev.setup.wLength);
212 spin_unlock_irq(&ffs->ev.waitq.lock);
218 * UDC layer requires to provide a buffer even for ZLP, but should
219 * not use it at all. Let's provide some poisoned pointer to catch
220 * possible bug in the driver.
222 if (req->buf == NULL)
223 req->buf = (void *)0xDEADBABE;
225 reinit_completion(&ffs->ep0req_completion);
227 ret = usb_ep_queue(ffs->gadget->ep0, req, GFP_ATOMIC);
228 if (unlikely(ret < 0))
231 ret = wait_for_completion_interruptible(&ffs->ep0req_completion);
233 usb_ep_dequeue(ffs->gadget->ep0, req);
237 ffs->setup_state = FFS_NO_SETUP;
238 return req->status ? req->status : req->actual;
241 static int __ffs_ep0_stall(struct ffs_data *ffs)
243 if (ffs->ev.can_stall) {
244 pr_vdebug("ep0 stall\n");
245 usb_ep_set_halt(ffs->gadget->ep0);
246 ffs->setup_state = FFS_NO_SETUP;
249 pr_debug("bogus ep0 stall!\n");
254 static ssize_t ffs_ep0_write(struct file *file, const char __user *buf,
255 size_t len, loff_t *ptr)
257 struct ffs_data *ffs = file->private_data;
263 /* Fast check if setup was canceled */
264 if (ffs_setup_state_clear_cancelled(ffs) == FFS_SETUP_CANCELLED)
268 ret = ffs_mutex_lock(&ffs->mutex, file->f_flags & O_NONBLOCK);
269 if (unlikely(ret < 0))
273 switch (ffs->state) {
274 case FFS_READ_DESCRIPTORS:
275 case FFS_READ_STRINGS:
277 if (unlikely(len < 16)) {
282 data = ffs_prepare_buffer(buf, len);
289 if (ffs->state == FFS_READ_DESCRIPTORS) {
290 pr_info("read descriptors\n");
291 ret = __ffs_data_got_descs(ffs, data, len);
292 if (unlikely(ret < 0))
295 ffs->state = FFS_READ_STRINGS;
298 pr_info("read strings\n");
299 ret = __ffs_data_got_strings(ffs, data, len);
300 if (unlikely(ret < 0))
303 ret = ffs_epfiles_create(ffs);
305 ffs->state = FFS_CLOSING;
309 ffs->state = FFS_ACTIVE;
310 mutex_unlock(&ffs->mutex);
312 ret = ffs_ready(ffs);
313 if (unlikely(ret < 0)) {
314 ffs->state = FFS_CLOSING;
325 * We're called from user space, we can use _irq
326 * rather then _irqsave
328 spin_lock_irq(&ffs->ev.waitq.lock);
329 switch (ffs_setup_state_clear_cancelled(ffs)) {
330 case FFS_SETUP_CANCELLED:
338 case FFS_SETUP_PENDING:
342 /* FFS_SETUP_PENDING */
343 if (!(ffs->ev.setup.bRequestType & USB_DIR_IN)) {
344 spin_unlock_irq(&ffs->ev.waitq.lock);
345 ret = __ffs_ep0_stall(ffs);
349 /* FFS_SETUP_PENDING and not stall */
350 len = min(len, (size_t)le16_to_cpu(ffs->ev.setup.wLength));
352 spin_unlock_irq(&ffs->ev.waitq.lock);
354 data = ffs_prepare_buffer(buf, len);
360 spin_lock_irq(&ffs->ev.waitq.lock);
363 * We are guaranteed to be still in FFS_ACTIVE state
364 * but the state of setup could have changed from
365 * FFS_SETUP_PENDING to FFS_SETUP_CANCELLED so we need
366 * to check for that. If that happened we copied data
367 * from user space in vain but it's unlikely.
369 * For sure we are not in FFS_NO_SETUP since this is
370 * the only place FFS_SETUP_PENDING -> FFS_NO_SETUP
371 * transition can be performed and it's protected by
374 if (ffs_setup_state_clear_cancelled(ffs) ==
375 FFS_SETUP_CANCELLED) {
378 spin_unlock_irq(&ffs->ev.waitq.lock);
380 /* unlocks spinlock */
381 ret = __ffs_ep0_queue_wait(ffs, data, len);
391 mutex_unlock(&ffs->mutex);
395 /* Called with ffs->ev.waitq.lock and ffs->mutex held, both released on exit. */
396 static ssize_t __ffs_ep0_read_events(struct ffs_data *ffs, char __user *buf,
400 * n cannot be bigger than ffs->ev.count, which cannot be bigger than
401 * size of ffs->ev.types array (which is four) so that's how much space
404 struct usb_functionfs_event events[ARRAY_SIZE(ffs->ev.types)];
405 const size_t size = n * sizeof *events;
408 memset(events, 0, size);
411 events[i].type = ffs->ev.types[i];
412 if (events[i].type == FUNCTIONFS_SETUP) {
413 events[i].u.setup = ffs->ev.setup;
414 ffs->setup_state = FFS_SETUP_PENDING;
420 memmove(ffs->ev.types, ffs->ev.types + n,
421 ffs->ev.count * sizeof *ffs->ev.types);
423 spin_unlock_irq(&ffs->ev.waitq.lock);
424 mutex_unlock(&ffs->mutex);
426 return unlikely(copy_to_user(buf, events, size)) ? -EFAULT : size;
429 static ssize_t ffs_ep0_read(struct file *file, char __user *buf,
430 size_t len, loff_t *ptr)
432 struct ffs_data *ffs = file->private_data;
439 /* Fast check if setup was canceled */
440 if (ffs_setup_state_clear_cancelled(ffs) == FFS_SETUP_CANCELLED)
444 ret = ffs_mutex_lock(&ffs->mutex, file->f_flags & O_NONBLOCK);
445 if (unlikely(ret < 0))
449 if (ffs->state != FFS_ACTIVE) {
455 * We're called from user space, we can use _irq rather then
458 spin_lock_irq(&ffs->ev.waitq.lock);
460 switch (ffs_setup_state_clear_cancelled(ffs)) {
461 case FFS_SETUP_CANCELLED:
466 n = len / sizeof(struct usb_functionfs_event);
472 if ((file->f_flags & O_NONBLOCK) && !ffs->ev.count) {
477 if (wait_event_interruptible_exclusive_locked_irq(ffs->ev.waitq,
483 return __ffs_ep0_read_events(ffs, buf,
484 min(n, (size_t)ffs->ev.count));
486 case FFS_SETUP_PENDING:
487 if (ffs->ev.setup.bRequestType & USB_DIR_IN) {
488 spin_unlock_irq(&ffs->ev.waitq.lock);
489 ret = __ffs_ep0_stall(ffs);
493 len = min(len, (size_t)le16_to_cpu(ffs->ev.setup.wLength));
495 spin_unlock_irq(&ffs->ev.waitq.lock);
498 data = kmalloc(len, GFP_KERNEL);
499 if (unlikely(!data)) {
505 spin_lock_irq(&ffs->ev.waitq.lock);
507 /* See ffs_ep0_write() */
508 if (ffs_setup_state_clear_cancelled(ffs) ==
509 FFS_SETUP_CANCELLED) {
514 /* unlocks spinlock */
515 ret = __ffs_ep0_queue_wait(ffs, data, len);
516 if (likely(ret > 0) && unlikely(copy_to_user(buf, data, len)))
525 spin_unlock_irq(&ffs->ev.waitq.lock);
527 mutex_unlock(&ffs->mutex);
532 static int ffs_ep0_open(struct inode *inode, struct file *file)
534 struct ffs_data *ffs = inode->i_private;
538 if (unlikely(ffs->state == FFS_CLOSING))
541 file->private_data = ffs;
542 ffs_data_opened(ffs);
547 static int ffs_ep0_release(struct inode *inode, struct file *file)
549 struct ffs_data *ffs = file->private_data;
553 ffs_data_closed(ffs);
558 static long ffs_ep0_ioctl(struct file *file, unsigned code, unsigned long value)
560 struct ffs_data *ffs = file->private_data;
561 struct usb_gadget *gadget = ffs->gadget;
566 if (code == FUNCTIONFS_INTERFACE_REVMAP) {
567 struct ffs_function *func = ffs->func;
568 ret = func ? ffs_func_revmap_intf(func, value) : -ENODEV;
569 } else if (gadget && gadget->ops->ioctl) {
570 ret = gadget->ops->ioctl(gadget, code, value);
578 static unsigned int ffs_ep0_poll(struct file *file, poll_table *wait)
580 struct ffs_data *ffs = file->private_data;
581 unsigned int mask = POLLWRNORM;
584 poll_wait(file, &ffs->ev.waitq, wait);
586 ret = ffs_mutex_lock(&ffs->mutex, file->f_flags & O_NONBLOCK);
587 if (unlikely(ret < 0))
590 switch (ffs->state) {
591 case FFS_READ_DESCRIPTORS:
592 case FFS_READ_STRINGS:
597 switch (ffs->setup_state) {
603 case FFS_SETUP_PENDING:
604 case FFS_SETUP_CANCELLED:
605 mask |= (POLLIN | POLLOUT);
610 case FFS_DEACTIVATED:
614 mutex_unlock(&ffs->mutex);
619 static const struct file_operations ffs_ep0_operations = {
622 .open = ffs_ep0_open,
623 .write = ffs_ep0_write,
624 .read = ffs_ep0_read,
625 .release = ffs_ep0_release,
626 .unlocked_ioctl = ffs_ep0_ioctl,
627 .poll = ffs_ep0_poll,
631 /* "Normal" endpoints operations ********************************************/
633 static void ffs_epfile_io_complete(struct usb_ep *_ep, struct usb_request *req)
636 if (likely(req->context)) {
637 struct ffs_ep *ep = _ep->driver_data;
638 ep->status = req->status ? req->status : req->actual;
639 complete(req->context);
643 static void ffs_user_copy_worker(struct work_struct *work)
645 struct ffs_io_data *io_data = container_of(work, struct ffs_io_data,
647 int ret = io_data->req->status ? io_data->req->status :
648 io_data->req->actual;
649 bool kiocb_has_eventfd = io_data->kiocb->ki_flags & IOCB_EVENTFD;
651 if (io_data->read && ret > 0) {
652 mm_segment_t oldfs = get_fs();
656 ret = copy_to_iter(io_data->buf, ret, &io_data->data);
657 if (ret != io_data->req->actual && iov_iter_count(&io_data->data))
659 unuse_mm(io_data->mm);
663 io_data->kiocb->ki_complete(io_data->kiocb, ret, ret);
665 if (io_data->ffs->ffs_eventfd && !kiocb_has_eventfd)
666 eventfd_signal(io_data->ffs->ffs_eventfd, 1);
668 usb_ep_free_request(io_data->ep, io_data->req);
671 kfree(io_data->to_free);
676 static void ffs_epfile_async_io_complete(struct usb_ep *_ep,
677 struct usb_request *req)
679 struct ffs_io_data *io_data = req->context;
683 INIT_WORK(&io_data->work, ffs_user_copy_worker);
684 schedule_work(&io_data->work);
687 static ssize_t ffs_epfile_io(struct file *file, struct ffs_io_data *io_data)
689 struct ffs_epfile *epfile = file->private_data;
692 ssize_t ret, data_len = -EINVAL;
695 /* Are we still active? */
696 if (WARN_ON(epfile->ffs->state != FFS_ACTIVE)) {
701 /* Wait for endpoint to be enabled */
704 if (file->f_flags & O_NONBLOCK) {
709 ret = wait_event_interruptible(epfile->wait, (ep = epfile->ep));
717 halt = (!io_data->read == !epfile->in);
718 if (halt && epfile->isoc) {
723 /* Allocate & copy */
726 * if we _do_ wait above, the epfile->ffs->gadget might be NULL
727 * before the waiting completes, so do not assign to 'gadget' earlier
729 struct usb_gadget *gadget = epfile->ffs->gadget;
732 spin_lock_irq(&epfile->ffs->eps_lock);
733 /* In the meantime, endpoint got disabled or changed. */
734 if (epfile->ep != ep) {
735 spin_unlock_irq(&epfile->ffs->eps_lock);
738 data_len = iov_iter_count(&io_data->data);
740 * Controller may require buffer size to be aligned to
741 * maxpacketsize of an out endpoint.
744 data_len = usb_ep_align_maybe(gadget, ep->ep, data_len);
745 spin_unlock_irq(&epfile->ffs->eps_lock);
747 data = kmalloc(data_len, GFP_KERNEL);
750 if (!io_data->read) {
751 copied = copy_from_iter(data, data_len, &io_data->data);
752 if (copied != data_len) {
759 /* We will be using request */
760 ret = ffs_mutex_lock(&epfile->mutex, file->f_flags & O_NONBLOCK);
764 spin_lock_irq(&epfile->ffs->eps_lock);
766 if (epfile->ep != ep) {
767 /* In the meantime, endpoint got disabled or changed. */
769 spin_unlock_irq(&epfile->ffs->eps_lock);
772 if (likely(epfile->ep == ep) && !WARN_ON(!ep->ep))
773 usb_ep_set_halt(ep->ep);
774 spin_unlock_irq(&epfile->ffs->eps_lock);
777 /* Fire the request */
778 struct usb_request *req;
781 * Sanity Check: even though data_len can't be used
782 * uninitialized at the time I write this comment, some
783 * compilers complain about this situation.
784 * In order to keep the code clean from warnings, data_len is
785 * being initialized to -EINVAL during its declaration, which
786 * means we can't rely on compiler anymore to warn no future
787 * changes won't result in data_len being used uninitialized.
788 * For such reason, we're adding this redundant sanity check
791 if (unlikely(data_len == -EINVAL)) {
792 WARN(1, "%s: data_len == -EINVAL\n", __func__);
798 req = usb_ep_alloc_request(ep->ep, GFP_ATOMIC);
803 req->length = data_len;
806 io_data->ep = ep->ep;
808 io_data->ffs = epfile->ffs;
810 req->context = io_data;
811 req->complete = ffs_epfile_async_io_complete;
813 ret = usb_ep_queue(ep->ep, req, GFP_ATOMIC);
816 usb_ep_free_request(ep->ep, req);
821 spin_unlock_irq(&epfile->ffs->eps_lock);
823 DECLARE_COMPLETION_ONSTACK(done);
827 req->length = data_len;
829 req->context = &done;
830 req->complete = ffs_epfile_io_complete;
832 ret = usb_ep_queue(ep->ep, req, GFP_ATOMIC);
834 spin_unlock_irq(&epfile->ffs->eps_lock);
836 if (unlikely(ret < 0)) {
839 wait_for_completion_interruptible(&done))) {
841 usb_ep_dequeue(ep->ep, req);
844 * XXX We may end up silently droping data
845 * here. Since data_len (i.e. req->length) may
846 * be bigger than len (after being rounded up
847 * to maxpacketsize), we may end up with more
848 * data then user space has space for.
851 if (io_data->read && ret > 0) {
852 ret = copy_to_iter(data, ret, &io_data->data);
861 mutex_unlock(&epfile->mutex);
865 spin_unlock_irq(&epfile->ffs->eps_lock);
866 mutex_unlock(&epfile->mutex);
873 ffs_epfile_open(struct inode *inode, struct file *file)
875 struct ffs_epfile *epfile = inode->i_private;
879 if (WARN_ON(epfile->ffs->state != FFS_ACTIVE))
882 file->private_data = epfile;
883 ffs_data_opened(epfile->ffs);
888 static int ffs_aio_cancel(struct kiocb *kiocb)
890 struct ffs_io_data *io_data = kiocb->private;
891 struct ffs_epfile *epfile = kiocb->ki_filp->private_data;
897 spin_lock_irqsave(&epfile->ffs->eps_lock, flags);
899 if (likely(io_data && io_data->ep && io_data->req))
900 value = usb_ep_dequeue(io_data->ep, io_data->req);
904 spin_unlock_irqrestore(&epfile->ffs->eps_lock, flags);
909 static ssize_t ffs_epfile_write_iter(struct kiocb *kiocb, struct iov_iter *from)
911 struct ffs_io_data io_data, *p = &io_data;
916 if (!is_sync_kiocb(kiocb)) {
917 p = kzalloc(sizeof(io_data), GFP_KERNEL);
922 memset(p, 0, sizeof(*p));
934 kiocb_set_cancel_fn(kiocb, ffs_aio_cancel);
936 res = ffs_epfile_io(kiocb->ki_filp, p);
937 if (res == -EIOCBQUEUED)
946 static ssize_t ffs_epfile_read_iter(struct kiocb *kiocb, struct iov_iter *to)
948 struct ffs_io_data io_data, *p = &io_data;
953 if (!is_sync_kiocb(kiocb)) {
954 p = kzalloc(sizeof(io_data), GFP_KERNEL);
959 memset(p, 0, sizeof(*p));
966 p->to_free = dup_iter(&p->data, to, GFP_KERNEL);
980 kiocb_set_cancel_fn(kiocb, ffs_aio_cancel);
982 res = ffs_epfile_io(kiocb->ki_filp, p);
983 if (res == -EIOCBQUEUED)
996 ffs_epfile_release(struct inode *inode, struct file *file)
998 struct ffs_epfile *epfile = inode->i_private;
1002 ffs_data_closed(epfile->ffs);
1007 static long ffs_epfile_ioctl(struct file *file, unsigned code,
1008 unsigned long value)
1010 struct ffs_epfile *epfile = file->private_data;
1015 if (WARN_ON(epfile->ffs->state != FFS_ACTIVE))
1018 spin_lock_irq(&epfile->ffs->eps_lock);
1019 if (likely(epfile->ep)) {
1021 case FUNCTIONFS_FIFO_STATUS:
1022 ret = usb_ep_fifo_status(epfile->ep->ep);
1024 case FUNCTIONFS_FIFO_FLUSH:
1025 usb_ep_fifo_flush(epfile->ep->ep);
1028 case FUNCTIONFS_CLEAR_HALT:
1029 ret = usb_ep_clear_halt(epfile->ep->ep);
1031 case FUNCTIONFS_ENDPOINT_REVMAP:
1032 ret = epfile->ep->num;
1034 case FUNCTIONFS_ENDPOINT_DESC:
1037 struct usb_endpoint_descriptor desc1, *desc;
1039 switch (epfile->ffs->gadget->speed) {
1040 case USB_SPEED_SUPER:
1043 case USB_SPEED_HIGH:
1050 desc = epfile->ep->descs[desc_idx];
1051 memcpy(&desc1, desc, desc->bLength);
1053 spin_unlock_irq(&epfile->ffs->eps_lock);
1054 ret = copy_to_user((void *)value, &desc1, desc1.bLength);
1065 spin_unlock_irq(&epfile->ffs->eps_lock);
1070 static const struct file_operations ffs_epfile_operations = {
1071 .llseek = no_llseek,
1073 .open = ffs_epfile_open,
1074 .write_iter = ffs_epfile_write_iter,
1075 .read_iter = ffs_epfile_read_iter,
1076 .release = ffs_epfile_release,
1077 .unlocked_ioctl = ffs_epfile_ioctl,
1081 /* File system and super block operations ***********************************/
1084 * Mounting the file system creates a controller file, used first for
1085 * function configuration then later for event monitoring.
1088 static struct inode *__must_check
1089 ffs_sb_make_inode(struct super_block *sb, void *data,
1090 const struct file_operations *fops,
1091 const struct inode_operations *iops,
1092 struct ffs_file_perms *perms)
1094 struct inode *inode;
1098 inode = new_inode(sb);
1100 if (likely(inode)) {
1101 struct timespec current_time = CURRENT_TIME;
1103 inode->i_ino = get_next_ino();
1104 inode->i_mode = perms->mode;
1105 inode->i_uid = perms->uid;
1106 inode->i_gid = perms->gid;
1107 inode->i_atime = current_time;
1108 inode->i_mtime = current_time;
1109 inode->i_ctime = current_time;
1110 inode->i_private = data;
1112 inode->i_fop = fops;
1120 /* Create "regular" file */
1121 static struct dentry *ffs_sb_create_file(struct super_block *sb,
1122 const char *name, void *data,
1123 const struct file_operations *fops)
1125 struct ffs_data *ffs = sb->s_fs_info;
1126 struct dentry *dentry;
1127 struct inode *inode;
1131 dentry = d_alloc_name(sb->s_root, name);
1132 if (unlikely(!dentry))
1135 inode = ffs_sb_make_inode(sb, data, fops, NULL, &ffs->file_perms);
1136 if (unlikely(!inode)) {
1141 d_add(dentry, inode);
1146 static const struct super_operations ffs_sb_operations = {
1147 .statfs = simple_statfs,
1148 .drop_inode = generic_delete_inode,
1151 struct ffs_sb_fill_data {
1152 struct ffs_file_perms perms;
1154 const char *dev_name;
1156 struct ffs_data *ffs_data;
1159 static int ffs_sb_fill(struct super_block *sb, void *_data, int silent)
1161 struct ffs_sb_fill_data *data = _data;
1162 struct inode *inode;
1163 struct ffs_data *ffs = data->ffs_data;
1168 data->ffs_data = NULL;
1169 sb->s_fs_info = ffs;
1170 sb->s_blocksize = PAGE_CACHE_SIZE;
1171 sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
1172 sb->s_magic = FUNCTIONFS_MAGIC;
1173 sb->s_op = &ffs_sb_operations;
1174 sb->s_time_gran = 1;
1177 data->perms.mode = data->root_mode;
1178 inode = ffs_sb_make_inode(sb, NULL,
1179 &simple_dir_operations,
1180 &simple_dir_inode_operations,
1182 sb->s_root = d_make_root(inode);
1183 if (unlikely(!sb->s_root))
1187 if (unlikely(!ffs_sb_create_file(sb, "ep0", ffs,
1188 &ffs_ep0_operations)))
1194 static int ffs_fs_parse_opts(struct ffs_sb_fill_data *data, char *opts)
1198 if (!opts || !*opts)
1202 unsigned long value;
1206 comma = strchr(opts, ',');
1211 eq = strchr(opts, '=');
1212 if (unlikely(!eq)) {
1213 pr_err("'=' missing in %s\n", opts);
1219 if (kstrtoul(eq + 1, 0, &value)) {
1220 pr_err("%s: invalid value: %s\n", opts, eq + 1);
1224 /* Interpret option */
1225 switch (eq - opts) {
1227 if (!memcmp(opts, "no_disconnect", 13))
1228 data->no_disconnect = !!value;
1233 if (!memcmp(opts, "rmode", 5))
1234 data->root_mode = (value & 0555) | S_IFDIR;
1235 else if (!memcmp(opts, "fmode", 5))
1236 data->perms.mode = (value & 0666) | S_IFREG;
1242 if (!memcmp(opts, "mode", 4)) {
1243 data->root_mode = (value & 0555) | S_IFDIR;
1244 data->perms.mode = (value & 0666) | S_IFREG;
1251 if (!memcmp(opts, "uid", 3)) {
1252 data->perms.uid = make_kuid(current_user_ns(), value);
1253 if (!uid_valid(data->perms.uid)) {
1254 pr_err("%s: unmapped value: %lu\n", opts, value);
1257 } else if (!memcmp(opts, "gid", 3)) {
1258 data->perms.gid = make_kgid(current_user_ns(), value);
1259 if (!gid_valid(data->perms.gid)) {
1260 pr_err("%s: unmapped value: %lu\n", opts, value);
1270 pr_err("%s: invalid option\n", opts);
1274 /* Next iteration */
1283 /* "mount -t functionfs dev_name /dev/function" ends up here */
1285 static struct dentry *
1286 ffs_fs_mount(struct file_system_type *t, int flags,
1287 const char *dev_name, void *opts)
1289 struct ffs_sb_fill_data data = {
1291 .mode = S_IFREG | 0600,
1292 .uid = GLOBAL_ROOT_UID,
1293 .gid = GLOBAL_ROOT_GID,
1295 .root_mode = S_IFDIR | 0500,
1296 .no_disconnect = false,
1301 struct ffs_data *ffs;
1305 ret = ffs_fs_parse_opts(&data, opts);
1306 if (unlikely(ret < 0))
1307 return ERR_PTR(ret);
1309 ffs = ffs_data_new();
1311 return ERR_PTR(-ENOMEM);
1312 ffs->file_perms = data.perms;
1313 ffs->no_disconnect = data.no_disconnect;
1315 ffs->dev_name = kstrdup(dev_name, GFP_KERNEL);
1316 if (unlikely(!ffs->dev_name)) {
1318 return ERR_PTR(-ENOMEM);
1321 ffs_dev = ffs_acquire_dev(dev_name);
1322 if (IS_ERR(ffs_dev)) {
1324 return ERR_CAST(ffs_dev);
1326 ffs->private_data = ffs_dev;
1327 data.ffs_data = ffs;
1329 rv = mount_nodev(t, flags, &data, ffs_sb_fill);
1330 if (IS_ERR(rv) && data.ffs_data) {
1331 ffs_release_dev(data.ffs_data);
1332 ffs_data_put(data.ffs_data);
1338 ffs_fs_kill_sb(struct super_block *sb)
1342 kill_litter_super(sb);
1343 if (sb->s_fs_info) {
1344 ffs_release_dev(sb->s_fs_info);
1345 ffs_data_closed(sb->s_fs_info);
1349 static struct file_system_type ffs_fs_type = {
1350 .owner = THIS_MODULE,
1351 .name = "functionfs",
1352 .mount = ffs_fs_mount,
1353 .kill_sb = ffs_fs_kill_sb,
1355 MODULE_ALIAS_FS("functionfs");
1358 /* Driver's main init/cleanup functions *************************************/
1360 static int functionfs_init(void)
1366 ret = register_filesystem(&ffs_fs_type);
1368 pr_info("file system registered\n");
1370 pr_err("failed registering file system (%d)\n", ret);
1375 static void functionfs_cleanup(void)
1379 pr_info("unloading\n");
1380 unregister_filesystem(&ffs_fs_type);
1384 /* ffs_data and ffs_function construction and destruction code **************/
1386 static void ffs_data_clear(struct ffs_data *ffs);
1387 static void ffs_data_reset(struct ffs_data *ffs);
1389 static void ffs_data_get(struct ffs_data *ffs)
1393 atomic_inc(&ffs->ref);
1396 static void ffs_data_opened(struct ffs_data *ffs)
1400 atomic_inc(&ffs->ref);
1401 if (atomic_add_return(1, &ffs->opened) == 1 &&
1402 ffs->state == FFS_DEACTIVATED) {
1403 ffs->state = FFS_CLOSING;
1404 ffs_data_reset(ffs);
1408 static void ffs_data_put(struct ffs_data *ffs)
1412 if (unlikely(atomic_dec_and_test(&ffs->ref))) {
1413 pr_info("%s(): freeing\n", __func__);
1414 ffs_data_clear(ffs);
1415 BUG_ON(waitqueue_active(&ffs->ev.waitq) ||
1416 waitqueue_active(&ffs->ep0req_completion.wait));
1417 kfree(ffs->dev_name);
1422 static void ffs_data_closed(struct ffs_data *ffs)
1426 if (atomic_dec_and_test(&ffs->opened)) {
1427 if (ffs->no_disconnect) {
1428 ffs->state = FFS_DEACTIVATED;
1430 ffs_epfiles_destroy(ffs->epfiles,
1432 ffs->epfiles = NULL;
1434 if (ffs->setup_state == FFS_SETUP_PENDING)
1435 __ffs_ep0_stall(ffs);
1437 ffs->state = FFS_CLOSING;
1438 ffs_data_reset(ffs);
1441 if (atomic_read(&ffs->opened) < 0) {
1442 ffs->state = FFS_CLOSING;
1443 ffs_data_reset(ffs);
1449 static struct ffs_data *ffs_data_new(void)
1451 struct ffs_data *ffs = kzalloc(sizeof *ffs, GFP_KERNEL);
1457 atomic_set(&ffs->ref, 1);
1458 atomic_set(&ffs->opened, 0);
1459 ffs->state = FFS_READ_DESCRIPTORS;
1460 mutex_init(&ffs->mutex);
1461 spin_lock_init(&ffs->eps_lock);
1462 init_waitqueue_head(&ffs->ev.waitq);
1463 init_completion(&ffs->ep0req_completion);
1465 /* XXX REVISIT need to update it in some places, or do we? */
1466 ffs->ev.can_stall = 1;
1471 static void ffs_data_clear(struct ffs_data *ffs)
1477 BUG_ON(ffs->gadget);
1480 ffs_epfiles_destroy(ffs->epfiles, ffs->eps_count);
1482 if (ffs->ffs_eventfd)
1483 eventfd_ctx_put(ffs->ffs_eventfd);
1485 kfree(ffs->raw_descs_data);
1486 kfree(ffs->raw_strings);
1487 kfree(ffs->stringtabs);
1490 static void ffs_data_reset(struct ffs_data *ffs)
1494 ffs_data_clear(ffs);
1496 ffs->epfiles = NULL;
1497 ffs->raw_descs_data = NULL;
1498 ffs->raw_descs = NULL;
1499 ffs->raw_strings = NULL;
1500 ffs->stringtabs = NULL;
1502 ffs->raw_descs_length = 0;
1503 ffs->fs_descs_count = 0;
1504 ffs->hs_descs_count = 0;
1505 ffs->ss_descs_count = 0;
1507 ffs->strings_count = 0;
1508 ffs->interfaces_count = 0;
1513 ffs->state = FFS_READ_DESCRIPTORS;
1514 ffs->setup_state = FFS_NO_SETUP;
1517 ffs->ms_os_descs_ext_prop_count = 0;
1518 ffs->ms_os_descs_ext_prop_name_len = 0;
1519 ffs->ms_os_descs_ext_prop_data_len = 0;
1523 static int functionfs_bind(struct ffs_data *ffs, struct usb_composite_dev *cdev)
1525 struct usb_gadget_strings **lang;
1530 if (WARN_ON(ffs->state != FFS_ACTIVE
1531 || test_and_set_bit(FFS_FL_BOUND, &ffs->flags)))
1534 first_id = usb_string_ids_n(cdev, ffs->strings_count);
1535 if (unlikely(first_id < 0))
1538 ffs->ep0req = usb_ep_alloc_request(cdev->gadget->ep0, GFP_KERNEL);
1539 if (unlikely(!ffs->ep0req))
1541 ffs->ep0req->complete = ffs_ep0_complete;
1542 ffs->ep0req->context = ffs;
1544 lang = ffs->stringtabs;
1546 for (; *lang; ++lang) {
1547 struct usb_string *str = (*lang)->strings;
1549 for (; str->s; ++id, ++str)
1554 ffs->gadget = cdev->gadget;
1559 static void functionfs_unbind(struct ffs_data *ffs)
1563 if (!WARN_ON(!ffs->gadget)) {
1564 usb_ep_free_request(ffs->gadget->ep0, ffs->ep0req);
1567 clear_bit(FFS_FL_BOUND, &ffs->flags);
1572 static int ffs_epfiles_create(struct ffs_data *ffs)
1574 struct ffs_epfile *epfile, *epfiles;
1579 count = ffs->eps_count;
1580 epfiles = kcalloc(count, sizeof(*epfiles), GFP_KERNEL);
1585 for (i = 1; i <= count; ++i, ++epfile) {
1587 mutex_init(&epfile->mutex);
1588 init_waitqueue_head(&epfile->wait);
1589 if (ffs->user_flags & FUNCTIONFS_VIRTUAL_ADDR)
1590 sprintf(epfile->name, "ep%02x", ffs->eps_addrmap[i]);
1592 sprintf(epfile->name, "ep%u", i);
1593 epfile->dentry = ffs_sb_create_file(ffs->sb, epfile->name,
1595 &ffs_epfile_operations);
1596 if (unlikely(!epfile->dentry)) {
1597 ffs_epfiles_destroy(epfiles, i - 1);
1602 ffs->epfiles = epfiles;
1606 static void ffs_epfiles_destroy(struct ffs_epfile *epfiles, unsigned count)
1608 struct ffs_epfile *epfile = epfiles;
1612 for (; count; --count, ++epfile) {
1613 BUG_ON(mutex_is_locked(&epfile->mutex) ||
1614 waitqueue_active(&epfile->wait));
1615 if (epfile->dentry) {
1616 d_delete(epfile->dentry);
1617 dput(epfile->dentry);
1618 epfile->dentry = NULL;
1625 static void ffs_func_eps_disable(struct ffs_function *func)
1627 struct ffs_ep *ep = func->eps;
1628 struct ffs_epfile *epfile = func->ffs->epfiles;
1629 unsigned count = func->ffs->eps_count;
1630 unsigned long flags;
1632 spin_lock_irqsave(&func->ffs->eps_lock, flags);
1634 /* pending requests get nuked */
1636 usb_ep_disable(ep->ep);
1644 spin_unlock_irqrestore(&func->ffs->eps_lock, flags);
1647 static int ffs_func_eps_enable(struct ffs_function *func)
1649 struct ffs_data *ffs = func->ffs;
1650 struct ffs_ep *ep = func->eps;
1651 struct ffs_epfile *epfile = ffs->epfiles;
1652 unsigned count = ffs->eps_count;
1653 unsigned long flags;
1656 spin_lock_irqsave(&func->ffs->eps_lock, flags);
1658 struct usb_endpoint_descriptor *ds;
1659 struct usb_ss_ep_comp_descriptor *comp_desc = NULL;
1660 int needs_comp_desc = false;
1663 if (ffs->gadget->speed == USB_SPEED_SUPER) {
1665 needs_comp_desc = true;
1666 } else if (ffs->gadget->speed == USB_SPEED_HIGH)
1671 /* fall-back to lower speed if desc missing for current speed */
1673 ds = ep->descs[desc_idx];
1674 } while (!ds && --desc_idx >= 0);
1681 ep->ep->driver_data = ep;
1684 if (needs_comp_desc) {
1685 comp_desc = (struct usb_ss_ep_comp_descriptor *)(ds +
1686 USB_DT_ENDPOINT_SIZE);
1687 ep->ep->maxburst = comp_desc->bMaxBurst + 1;
1688 ep->ep->comp_desc = comp_desc;
1691 ret = usb_ep_enable(ep->ep);
1694 epfile->in = usb_endpoint_dir_in(ds);
1695 epfile->isoc = usb_endpoint_xfer_isoc(ds);
1700 wake_up(&epfile->wait);
1705 spin_unlock_irqrestore(&func->ffs->eps_lock, flags);
1711 /* Parsing and building descriptors and strings *****************************/
1714 * This validates if data pointed by data is a valid USB descriptor as
1715 * well as record how many interfaces, endpoints and strings are
1716 * required by given configuration. Returns address after the
1717 * descriptor or NULL if data is invalid.
1720 enum ffs_entity_type {
1721 FFS_DESCRIPTOR, FFS_INTERFACE, FFS_STRING, FFS_ENDPOINT
1724 enum ffs_os_desc_type {
1725 FFS_OS_DESC, FFS_OS_DESC_EXT_COMPAT, FFS_OS_DESC_EXT_PROP
1728 typedef int (*ffs_entity_callback)(enum ffs_entity_type entity,
1730 struct usb_descriptor_header *desc,
1733 typedef int (*ffs_os_desc_callback)(enum ffs_os_desc_type entity,
1734 struct usb_os_desc_header *h, void *data,
1735 unsigned len, void *priv);
1737 static int __must_check ffs_do_single_desc(char *data, unsigned len,
1738 ffs_entity_callback entity,
1741 struct usb_descriptor_header *_ds = (void *)data;
1747 /* At least two bytes are required: length and type */
1749 pr_vdebug("descriptor too short\n");
1753 /* If we have at least as many bytes as the descriptor takes? */
1754 length = _ds->bLength;
1756 pr_vdebug("descriptor longer then available data\n");
1760 #define __entity_check_INTERFACE(val) 1
1761 #define __entity_check_STRING(val) (val)
1762 #define __entity_check_ENDPOINT(val) ((val) & USB_ENDPOINT_NUMBER_MASK)
1763 #define __entity(type, val) do { \
1764 pr_vdebug("entity " #type "(%02x)\n", (val)); \
1765 if (unlikely(!__entity_check_ ##type(val))) { \
1766 pr_vdebug("invalid entity's value\n"); \
1769 ret = entity(FFS_ ##type, &val, _ds, priv); \
1770 if (unlikely(ret < 0)) { \
1771 pr_debug("entity " #type "(%02x); ret = %d\n", \
1777 /* Parse descriptor depending on type. */
1778 switch (_ds->bDescriptorType) {
1782 case USB_DT_DEVICE_QUALIFIER:
1783 /* function can't have any of those */
1784 pr_vdebug("descriptor reserved for gadget: %d\n",
1785 _ds->bDescriptorType);
1788 case USB_DT_INTERFACE: {
1789 struct usb_interface_descriptor *ds = (void *)_ds;
1790 pr_vdebug("interface descriptor\n");
1791 if (length != sizeof *ds)
1794 __entity(INTERFACE, ds->bInterfaceNumber);
1796 __entity(STRING, ds->iInterface);
1800 case USB_DT_ENDPOINT: {
1801 struct usb_endpoint_descriptor *ds = (void *)_ds;
1802 pr_vdebug("endpoint descriptor\n");
1803 if (length != USB_DT_ENDPOINT_SIZE &&
1804 length != USB_DT_ENDPOINT_AUDIO_SIZE)
1806 __entity(ENDPOINT, ds->bEndpointAddress);
1811 pr_vdebug("hid descriptor\n");
1812 if (length != sizeof(struct hid_descriptor))
1817 if (length != sizeof(struct usb_otg_descriptor))
1821 case USB_DT_INTERFACE_ASSOCIATION: {
1822 struct usb_interface_assoc_descriptor *ds = (void *)_ds;
1823 pr_vdebug("interface association descriptor\n");
1824 if (length != sizeof *ds)
1827 __entity(STRING, ds->iFunction);
1831 case USB_DT_SS_ENDPOINT_COMP:
1832 pr_vdebug("EP SS companion descriptor\n");
1833 if (length != sizeof(struct usb_ss_ep_comp_descriptor))
1837 case USB_DT_OTHER_SPEED_CONFIG:
1838 case USB_DT_INTERFACE_POWER:
1840 case USB_DT_SECURITY:
1841 case USB_DT_CS_RADIO_CONTROL:
1843 pr_vdebug("unimplemented descriptor: %d\n", _ds->bDescriptorType);
1847 /* We should never be here */
1848 pr_vdebug("unknown descriptor: %d\n", _ds->bDescriptorType);
1852 pr_vdebug("invalid length: %d (descriptor %d)\n",
1853 _ds->bLength, _ds->bDescriptorType);
1858 #undef __entity_check_DESCRIPTOR
1859 #undef __entity_check_INTERFACE
1860 #undef __entity_check_STRING
1861 #undef __entity_check_ENDPOINT
1866 static int __must_check ffs_do_descs(unsigned count, char *data, unsigned len,
1867 ffs_entity_callback entity, void *priv)
1869 const unsigned _len = len;
1870 unsigned long num = 0;
1880 /* Record "descriptor" entity */
1881 ret = entity(FFS_DESCRIPTOR, (u8 *)num, (void *)data, priv);
1882 if (unlikely(ret < 0)) {
1883 pr_debug("entity DESCRIPTOR(%02lx); ret = %d\n",
1891 ret = ffs_do_single_desc(data, len, entity, priv);
1892 if (unlikely(ret < 0)) {
1893 pr_debug("%s returns %d\n", __func__, ret);
1903 static int __ffs_data_do_entity(enum ffs_entity_type type,
1904 u8 *valuep, struct usb_descriptor_header *desc,
1907 struct ffs_desc_helper *helper = priv;
1908 struct usb_endpoint_descriptor *d;
1913 case FFS_DESCRIPTOR:
1918 * Interfaces are indexed from zero so if we
1919 * encountered interface "n" then there are at least
1922 if (*valuep >= helper->interfaces_count)
1923 helper->interfaces_count = *valuep + 1;
1928 * Strings are indexed from 1 (0 is magic ;) reserved
1929 * for languages list or some such)
1931 if (*valuep > helper->ffs->strings_count)
1932 helper->ffs->strings_count = *valuep;
1937 helper->eps_count++;
1938 if (helper->eps_count >= 15)
1940 /* Check if descriptors for any speed were already parsed */
1941 if (!helper->ffs->eps_count && !helper->ffs->interfaces_count)
1942 helper->ffs->eps_addrmap[helper->eps_count] =
1943 d->bEndpointAddress;
1944 else if (helper->ffs->eps_addrmap[helper->eps_count] !=
1945 d->bEndpointAddress)
1953 static int __ffs_do_os_desc_header(enum ffs_os_desc_type *next_type,
1954 struct usb_os_desc_header *desc)
1956 u16 bcd_version = le16_to_cpu(desc->bcdVersion);
1957 u16 w_index = le16_to_cpu(desc->wIndex);
1959 if (bcd_version != 1) {
1960 pr_vdebug("unsupported os descriptors version: %d",
1966 *next_type = FFS_OS_DESC_EXT_COMPAT;
1969 *next_type = FFS_OS_DESC_EXT_PROP;
1972 pr_vdebug("unsupported os descriptor type: %d", w_index);
1976 return sizeof(*desc);
1980 * Process all extended compatibility/extended property descriptors
1981 * of a feature descriptor
1983 static int __must_check ffs_do_single_os_desc(char *data, unsigned len,
1984 enum ffs_os_desc_type type,
1986 ffs_os_desc_callback entity,
1988 struct usb_os_desc_header *h)
1991 const unsigned _len = len;
1995 /* loop over all ext compat/ext prop descriptors */
1996 while (feature_count--) {
1997 ret = entity(type, h, data, len, priv);
1998 if (unlikely(ret < 0)) {
1999 pr_debug("bad OS descriptor, type: %d\n", type);
2008 /* Process a number of complete Feature Descriptors (Ext Compat or Ext Prop) */
2009 static int __must_check ffs_do_os_descs(unsigned count,
2010 char *data, unsigned len,
2011 ffs_os_desc_callback entity, void *priv)
2013 const unsigned _len = len;
2014 unsigned long num = 0;
2018 for (num = 0; num < count; ++num) {
2020 enum ffs_os_desc_type type;
2022 struct usb_os_desc_header *desc = (void *)data;
2024 if (len < sizeof(*desc))
2028 * Record "descriptor" entity.
2029 * Process dwLength, bcdVersion, wIndex, get b/wCount.
2030 * Move the data pointer to the beginning of extended
2031 * compatibilities proper or extended properties proper
2032 * portions of the data
2034 if (le32_to_cpu(desc->dwLength) > len)
2037 ret = __ffs_do_os_desc_header(&type, desc);
2038 if (unlikely(ret < 0)) {
2039 pr_debug("entity OS_DESCRIPTOR(%02lx); ret = %d\n",
2044 * 16-bit hex "?? 00" Little Endian looks like 8-bit hex "??"
2046 feature_count = le16_to_cpu(desc->wCount);
2047 if (type == FFS_OS_DESC_EXT_COMPAT &&
2048 (feature_count > 255 || desc->Reserved))
2054 * Process all function/property descriptors
2055 * of this Feature Descriptor
2057 ret = ffs_do_single_os_desc(data, len, type,
2058 feature_count, entity, priv, desc);
2059 if (unlikely(ret < 0)) {
2060 pr_debug("%s returns %d\n", __func__, ret);
2071 * Validate contents of the buffer from userspace related to OS descriptors.
2073 static int __ffs_data_do_os_desc(enum ffs_os_desc_type type,
2074 struct usb_os_desc_header *h, void *data,
2075 unsigned len, void *priv)
2077 struct ffs_data *ffs = priv;
2083 case FFS_OS_DESC_EXT_COMPAT: {
2084 struct usb_ext_compat_desc *d = data;
2087 if (len < sizeof(*d) ||
2088 d->bFirstInterfaceNumber >= ffs->interfaces_count ||
2091 for (i = 0; i < ARRAY_SIZE(d->Reserved2); ++i)
2092 if (d->Reserved2[i])
2095 length = sizeof(struct usb_ext_compat_desc);
2098 case FFS_OS_DESC_EXT_PROP: {
2099 struct usb_ext_prop_desc *d = data;
2103 if (len < sizeof(*d) || h->interface >= ffs->interfaces_count)
2105 length = le32_to_cpu(d->dwSize);
2108 type = le32_to_cpu(d->dwPropertyDataType);
2109 if (type < USB_EXT_PROP_UNICODE ||
2110 type > USB_EXT_PROP_UNICODE_MULTI) {
2111 pr_vdebug("unsupported os descriptor property type: %d",
2115 pnl = le16_to_cpu(d->wPropertyNameLength);
2116 if (length < 14 + pnl) {
2117 pr_vdebug("invalid os descriptor length: %d pnl:%d (descriptor %d)\n",
2121 pdl = le32_to_cpu(*(u32 *)((u8 *)data + 10 + pnl));
2122 if (length != 14 + pnl + pdl) {
2123 pr_vdebug("invalid os descriptor length: %d pnl:%d pdl:%d (descriptor %d)\n",
2124 length, pnl, pdl, type);
2127 ++ffs->ms_os_descs_ext_prop_count;
2128 /* property name reported to the host as "WCHAR"s */
2129 ffs->ms_os_descs_ext_prop_name_len += pnl * 2;
2130 ffs->ms_os_descs_ext_prop_data_len += pdl;
2134 pr_vdebug("unknown descriptor: %d\n", type);
2140 static int __ffs_data_got_descs(struct ffs_data *ffs,
2141 char *const _data, size_t len)
2143 char *data = _data, *raw_descs;
2144 unsigned os_descs_count = 0, counts[3], flags;
2145 int ret = -EINVAL, i;
2146 struct ffs_desc_helper helper;
2150 if (get_unaligned_le32(data + 4) != len)
2153 switch (get_unaligned_le32(data)) {
2154 case FUNCTIONFS_DESCRIPTORS_MAGIC:
2155 flags = FUNCTIONFS_HAS_FS_DESC | FUNCTIONFS_HAS_HS_DESC;
2159 case FUNCTIONFS_DESCRIPTORS_MAGIC_V2:
2160 flags = get_unaligned_le32(data + 8);
2161 ffs->user_flags = flags;
2162 if (flags & ~(FUNCTIONFS_HAS_FS_DESC |
2163 FUNCTIONFS_HAS_HS_DESC |
2164 FUNCTIONFS_HAS_SS_DESC |
2165 FUNCTIONFS_HAS_MS_OS_DESC |
2166 FUNCTIONFS_VIRTUAL_ADDR |
2167 FUNCTIONFS_EVENTFD)) {
2178 if (flags & FUNCTIONFS_EVENTFD) {
2182 eventfd_ctx_fdget((int)get_unaligned_le32(data));
2183 if (IS_ERR(ffs->ffs_eventfd)) {
2184 ret = PTR_ERR(ffs->ffs_eventfd);
2185 ffs->ffs_eventfd = NULL;
2192 /* Read fs_count, hs_count and ss_count (if present) */
2193 for (i = 0; i < 3; ++i) {
2194 if (!(flags & (1 << i))) {
2196 } else if (len < 4) {
2199 counts[i] = get_unaligned_le32(data);
2204 if (flags & (1 << i)) {
2208 os_descs_count = get_unaligned_le32(data);
2213 /* Read descriptors */
2216 for (i = 0; i < 3; ++i) {
2219 helper.interfaces_count = 0;
2220 helper.eps_count = 0;
2221 ret = ffs_do_descs(counts[i], data, len,
2222 __ffs_data_do_entity, &helper);
2225 if (!ffs->eps_count && !ffs->interfaces_count) {
2226 ffs->eps_count = helper.eps_count;
2227 ffs->interfaces_count = helper.interfaces_count;
2229 if (ffs->eps_count != helper.eps_count) {
2233 if (ffs->interfaces_count != helper.interfaces_count) {
2241 if (os_descs_count) {
2242 ret = ffs_do_os_descs(os_descs_count, data, len,
2243 __ffs_data_do_os_desc, ffs);
2250 if (raw_descs == data || len) {
2255 ffs->raw_descs_data = _data;
2256 ffs->raw_descs = raw_descs;
2257 ffs->raw_descs_length = data - raw_descs;
2258 ffs->fs_descs_count = counts[0];
2259 ffs->hs_descs_count = counts[1];
2260 ffs->ss_descs_count = counts[2];
2261 ffs->ms_os_descs_count = os_descs_count;
2270 static int __ffs_data_got_strings(struct ffs_data *ffs,
2271 char *const _data, size_t len)
2273 u32 str_count, needed_count, lang_count;
2274 struct usb_gadget_strings **stringtabs, *t;
2275 struct usb_string *strings, *s;
2276 const char *data = _data;
2280 if (unlikely(len < 16 ||
2281 get_unaligned_le32(data) != FUNCTIONFS_STRINGS_MAGIC ||
2282 get_unaligned_le32(data + 4) != len))
2284 str_count = get_unaligned_le32(data + 8);
2285 lang_count = get_unaligned_le32(data + 12);
2287 /* if one is zero the other must be zero */
2288 if (unlikely(!str_count != !lang_count))
2291 /* Do we have at least as many strings as descriptors need? */
2292 needed_count = ffs->strings_count;
2293 if (unlikely(str_count < needed_count))
2297 * If we don't need any strings just return and free all
2300 if (!needed_count) {
2305 /* Allocate everything in one chunk so there's less maintenance. */
2309 vla_item(d, struct usb_gadget_strings *, stringtabs,
2311 vla_item(d, struct usb_gadget_strings, stringtab, lang_count);
2312 vla_item(d, struct usb_string, strings,
2313 lang_count*(needed_count+1));
2315 char *vlabuf = kmalloc(vla_group_size(d), GFP_KERNEL);
2317 if (unlikely(!vlabuf)) {
2322 /* Initialize the VLA pointers */
2323 stringtabs = vla_ptr(vlabuf, d, stringtabs);
2324 t = vla_ptr(vlabuf, d, stringtab);
2327 *stringtabs++ = t++;
2331 /* stringtabs = vlabuf = d_stringtabs for later kfree */
2332 stringtabs = vla_ptr(vlabuf, d, stringtabs);
2333 t = vla_ptr(vlabuf, d, stringtab);
2334 s = vla_ptr(vlabuf, d, strings);
2338 /* For each language */
2342 do { /* lang_count > 0 so we can use do-while */
2343 unsigned needed = needed_count;
2344 u32 str_per_lang = str_count;
2346 if (unlikely(len < 3))
2348 t->language = get_unaligned_le16(data);
2355 /* For each string */
2356 do { /* str_count > 0 so we can use do-while */
2357 size_t length = strnlen(data, len);
2359 if (unlikely(length == len))
2363 * User may provide more strings then we need,
2364 * if that's the case we simply ignore the
2367 if (likely(needed)) {
2369 * s->id will be set while adding
2370 * function to configuration so for
2371 * now just leave garbage here.
2380 } while (--str_per_lang);
2382 s->id = 0; /* terminator */
2386 } while (--lang_count);
2388 /* Some garbage left? */
2393 ffs->stringtabs = stringtabs;
2394 ffs->raw_strings = _data;
2406 /* Events handling and management *******************************************/
2408 static void __ffs_event_add(struct ffs_data *ffs,
2409 enum usb_functionfs_event_type type)
2411 enum usb_functionfs_event_type rem_type1, rem_type2 = type;
2415 * Abort any unhandled setup
2417 * We do not need to worry about some cmpxchg() changing value
2418 * of ffs->setup_state without holding the lock because when
2419 * state is FFS_SETUP_PENDING cmpxchg() in several places in
2420 * the source does nothing.
2422 if (ffs->setup_state == FFS_SETUP_PENDING)
2423 ffs->setup_state = FFS_SETUP_CANCELLED;
2426 * Logic of this function guarantees that there are at most four pending
2427 * evens on ffs->ev.types queue. This is important because the queue
2428 * has space for four elements only and __ffs_ep0_read_events function
2429 * depends on that limit as well. If more event types are added, those
2430 * limits have to be revisited or guaranteed to still hold.
2433 case FUNCTIONFS_RESUME:
2434 rem_type2 = FUNCTIONFS_SUSPEND;
2436 case FUNCTIONFS_SUSPEND:
2437 case FUNCTIONFS_SETUP:
2439 /* Discard all similar events */
2442 case FUNCTIONFS_BIND:
2443 case FUNCTIONFS_UNBIND:
2444 case FUNCTIONFS_DISABLE:
2445 case FUNCTIONFS_ENABLE:
2446 /* Discard everything other then power management. */
2447 rem_type1 = FUNCTIONFS_SUSPEND;
2448 rem_type2 = FUNCTIONFS_RESUME;
2453 WARN(1, "%d: unknown event, this should not happen\n", type);
2458 u8 *ev = ffs->ev.types, *out = ev;
2459 unsigned n = ffs->ev.count;
2460 for (; n; --n, ++ev)
2461 if ((*ev == rem_type1 || *ev == rem_type2) == neg)
2464 pr_vdebug("purging event %d\n", *ev);
2465 ffs->ev.count = out - ffs->ev.types;
2468 pr_vdebug("adding event %d\n", type);
2469 ffs->ev.types[ffs->ev.count++] = type;
2470 wake_up_locked(&ffs->ev.waitq);
2471 if (ffs->ffs_eventfd)
2472 eventfd_signal(ffs->ffs_eventfd, 1);
2475 static void ffs_event_add(struct ffs_data *ffs,
2476 enum usb_functionfs_event_type type)
2478 unsigned long flags;
2479 spin_lock_irqsave(&ffs->ev.waitq.lock, flags);
2480 __ffs_event_add(ffs, type);
2481 spin_unlock_irqrestore(&ffs->ev.waitq.lock, flags);
2484 /* Bind/unbind USB function hooks *******************************************/
2486 static int ffs_ep_addr2idx(struct ffs_data *ffs, u8 endpoint_address)
2490 for (i = 1; i < ARRAY_SIZE(ffs->eps_addrmap); ++i)
2491 if (ffs->eps_addrmap[i] == endpoint_address)
2496 static int __ffs_func_bind_do_descs(enum ffs_entity_type type, u8 *valuep,
2497 struct usb_descriptor_header *desc,
2500 struct usb_endpoint_descriptor *ds = (void *)desc;
2501 struct ffs_function *func = priv;
2502 struct ffs_ep *ffs_ep;
2503 unsigned ep_desc_id;
2505 static const char *speed_names[] = { "full", "high", "super" };
2507 if (type != FFS_DESCRIPTOR)
2511 * If ss_descriptors is not NULL, we are reading super speed
2512 * descriptors; if hs_descriptors is not NULL, we are reading high
2513 * speed descriptors; otherwise, we are reading full speed
2516 if (func->function.ss_descriptors) {
2518 func->function.ss_descriptors[(long)valuep] = desc;
2519 } else if (func->function.hs_descriptors) {
2521 func->function.hs_descriptors[(long)valuep] = desc;
2524 func->function.fs_descriptors[(long)valuep] = desc;
2527 if (!desc || desc->bDescriptorType != USB_DT_ENDPOINT)
2530 idx = ffs_ep_addr2idx(func->ffs, ds->bEndpointAddress) - 1;
2534 ffs_ep = func->eps + idx;
2536 if (unlikely(ffs_ep->descs[ep_desc_id])) {
2537 pr_err("two %sspeed descriptors for EP %d\n",
2538 speed_names[ep_desc_id],
2539 ds->bEndpointAddress & USB_ENDPOINT_NUMBER_MASK);
2542 ffs_ep->descs[ep_desc_id] = ds;
2544 ffs_dump_mem(": Original ep desc", ds, ds->bLength);
2546 ds->bEndpointAddress = ffs_ep->descs[0]->bEndpointAddress;
2547 if (!ds->wMaxPacketSize)
2548 ds->wMaxPacketSize = ffs_ep->descs[0]->wMaxPacketSize;
2550 struct usb_request *req;
2552 u8 bEndpointAddress;
2555 * We back up bEndpointAddress because autoconfig overwrites
2556 * it with physical endpoint address.
2558 bEndpointAddress = ds->bEndpointAddress;
2559 pr_vdebug("autoconfig\n");
2560 ep = usb_ep_autoconfig(func->gadget, ds);
2563 ep->driver_data = func->eps + idx;
2565 req = usb_ep_alloc_request(ep, GFP_KERNEL);
2571 func->eps_revmap[ds->bEndpointAddress &
2572 USB_ENDPOINT_NUMBER_MASK] = idx + 1;
2574 * If we use virtual address mapping, we restore
2575 * original bEndpointAddress value.
2577 if (func->ffs->user_flags & FUNCTIONFS_VIRTUAL_ADDR)
2578 ds->bEndpointAddress = bEndpointAddress;
2580 ffs_dump_mem(": Rewritten ep desc", ds, ds->bLength);
2585 static int __ffs_func_bind_do_nums(enum ffs_entity_type type, u8 *valuep,
2586 struct usb_descriptor_header *desc,
2589 struct ffs_function *func = priv;
2595 case FFS_DESCRIPTOR:
2596 /* Handled in previous pass by __ffs_func_bind_do_descs() */
2601 if (func->interfaces_nums[idx] < 0) {
2602 int id = usb_interface_id(func->conf, &func->function);
2603 if (unlikely(id < 0))
2605 func->interfaces_nums[idx] = id;
2607 newValue = func->interfaces_nums[idx];
2611 /* String' IDs are allocated when fsf_data is bound to cdev */
2612 newValue = func->ffs->stringtabs[0]->strings[*valuep - 1].id;
2617 * USB_DT_ENDPOINT are handled in
2618 * __ffs_func_bind_do_descs().
2620 if (desc->bDescriptorType == USB_DT_ENDPOINT)
2623 idx = (*valuep & USB_ENDPOINT_NUMBER_MASK) - 1;
2624 if (unlikely(!func->eps[idx].ep))
2628 struct usb_endpoint_descriptor **descs;
2629 descs = func->eps[idx].descs;
2630 newValue = descs[descs[0] ? 0 : 1]->bEndpointAddress;
2635 pr_vdebug("%02x -> %02x\n", *valuep, newValue);
2640 static int __ffs_func_bind_do_os_desc(enum ffs_os_desc_type type,
2641 struct usb_os_desc_header *h, void *data,
2642 unsigned len, void *priv)
2644 struct ffs_function *func = priv;
2648 case FFS_OS_DESC_EXT_COMPAT: {
2649 struct usb_ext_compat_desc *desc = data;
2650 struct usb_os_desc_table *t;
2652 t = &func->function.os_desc_table[desc->bFirstInterfaceNumber];
2653 t->if_id = func->interfaces_nums[desc->bFirstInterfaceNumber];
2654 memcpy(t->os_desc->ext_compat_id, &desc->CompatibleID,
2655 ARRAY_SIZE(desc->CompatibleID) +
2656 ARRAY_SIZE(desc->SubCompatibleID));
2657 length = sizeof(*desc);
2660 case FFS_OS_DESC_EXT_PROP: {
2661 struct usb_ext_prop_desc *desc = data;
2662 struct usb_os_desc_table *t;
2663 struct usb_os_desc_ext_prop *ext_prop;
2664 char *ext_prop_name;
2665 char *ext_prop_data;
2667 t = &func->function.os_desc_table[h->interface];
2668 t->if_id = func->interfaces_nums[h->interface];
2670 ext_prop = func->ffs->ms_os_descs_ext_prop_avail;
2671 func->ffs->ms_os_descs_ext_prop_avail += sizeof(*ext_prop);
2673 ext_prop->type = le32_to_cpu(desc->dwPropertyDataType);
2674 ext_prop->name_len = le16_to_cpu(desc->wPropertyNameLength);
2675 ext_prop->data_len = le32_to_cpu(*(u32 *)
2676 usb_ext_prop_data_len_ptr(data, ext_prop->name_len));
2677 length = ext_prop->name_len + ext_prop->data_len + 14;
2679 ext_prop_name = func->ffs->ms_os_descs_ext_prop_name_avail;
2680 func->ffs->ms_os_descs_ext_prop_name_avail +=
2683 ext_prop_data = func->ffs->ms_os_descs_ext_prop_data_avail;
2684 func->ffs->ms_os_descs_ext_prop_data_avail +=
2686 memcpy(ext_prop_data,
2687 usb_ext_prop_data_ptr(data, ext_prop->name_len),
2688 ext_prop->data_len);
2689 /* unicode data reported to the host as "WCHAR"s */
2690 switch (ext_prop->type) {
2691 case USB_EXT_PROP_UNICODE:
2692 case USB_EXT_PROP_UNICODE_ENV:
2693 case USB_EXT_PROP_UNICODE_LINK:
2694 case USB_EXT_PROP_UNICODE_MULTI:
2695 ext_prop->data_len *= 2;
2698 ext_prop->data = ext_prop_data;
2700 memcpy(ext_prop_name, usb_ext_prop_name_ptr(data),
2701 ext_prop->name_len);
2702 /* property name reported to the host as "WCHAR"s */
2703 ext_prop->name_len *= 2;
2704 ext_prop->name = ext_prop_name;
2706 t->os_desc->ext_prop_len +=
2707 ext_prop->name_len + ext_prop->data_len + 14;
2708 ++t->os_desc->ext_prop_count;
2709 list_add_tail(&ext_prop->entry, &t->os_desc->ext_prop);
2713 pr_vdebug("unknown descriptor: %d\n", type);
2719 static inline struct f_fs_opts *ffs_do_functionfs_bind(struct usb_function *f,
2720 struct usb_configuration *c)
2722 struct ffs_function *func = ffs_func_from_usb(f);
2723 struct f_fs_opts *ffs_opts =
2724 container_of(f->fi, struct f_fs_opts, func_inst);
2730 * Legacy gadget triggers binding in functionfs_ready_callback,
2731 * which already uses locking; taking the same lock here would
2734 * Configfs-enabled gadgets however do need ffs_dev_lock.
2736 if (!ffs_opts->no_configfs)
2738 ret = ffs_opts->dev->desc_ready ? 0 : -ENODEV;
2739 func->ffs = ffs_opts->dev->ffs_data;
2740 if (!ffs_opts->no_configfs)
2743 return ERR_PTR(ret);
2746 func->gadget = c->cdev->gadget;
2749 * in drivers/usb/gadget/configfs.c:configfs_composite_bind()
2750 * configurations are bound in sequence with list_for_each_entry,
2751 * in each configuration its functions are bound in sequence
2752 * with list_for_each_entry, so we assume no race condition
2753 * with regard to ffs_opts->bound access
2755 if (!ffs_opts->refcnt) {
2756 ret = functionfs_bind(func->ffs, c->cdev);
2758 return ERR_PTR(ret);
2761 func->function.strings = func->ffs->stringtabs;
2766 static int _ffs_func_bind(struct usb_configuration *c,
2767 struct usb_function *f)
2769 struct ffs_function *func = ffs_func_from_usb(f);
2770 struct ffs_data *ffs = func->ffs;
2772 const int full = !!func->ffs->fs_descs_count;
2773 const int high = !!func->ffs->hs_descs_count;
2774 const int super = !!func->ffs->ss_descs_count;
2776 int fs_len, hs_len, ss_len, ret, i;
2777 struct ffs_ep *eps_ptr;
2779 /* Make it a single chunk, less management later on */
2781 vla_item_with_sz(d, struct ffs_ep, eps, ffs->eps_count);
2782 vla_item_with_sz(d, struct usb_descriptor_header *, fs_descs,
2783 full ? ffs->fs_descs_count + 1 : 0);
2784 vla_item_with_sz(d, struct usb_descriptor_header *, hs_descs,
2785 high ? ffs->hs_descs_count + 1 : 0);
2786 vla_item_with_sz(d, struct usb_descriptor_header *, ss_descs,
2787 super ? ffs->ss_descs_count + 1 : 0);
2788 vla_item_with_sz(d, short, inums, ffs->interfaces_count);
2789 vla_item_with_sz(d, struct usb_os_desc_table, os_desc_table,
2790 c->cdev->use_os_string ? ffs->interfaces_count : 0);
2791 vla_item_with_sz(d, char[16], ext_compat,
2792 c->cdev->use_os_string ? ffs->interfaces_count : 0);
2793 vla_item_with_sz(d, struct usb_os_desc, os_desc,
2794 c->cdev->use_os_string ? ffs->interfaces_count : 0);
2795 vla_item_with_sz(d, struct usb_os_desc_ext_prop, ext_prop,
2796 ffs->ms_os_descs_ext_prop_count);
2797 vla_item_with_sz(d, char, ext_prop_name,
2798 ffs->ms_os_descs_ext_prop_name_len);
2799 vla_item_with_sz(d, char, ext_prop_data,
2800 ffs->ms_os_descs_ext_prop_data_len);
2801 vla_item_with_sz(d, char, raw_descs, ffs->raw_descs_length);
2806 /* Has descriptors only for speeds gadget does not support */
2807 if (unlikely(!(full | high | super)))
2810 /* Allocate a single chunk, less management later on */
2811 vlabuf = kzalloc(vla_group_size(d), GFP_KERNEL);
2812 if (unlikely(!vlabuf))
2815 ffs->ms_os_descs_ext_prop_avail = vla_ptr(vlabuf, d, ext_prop);
2816 ffs->ms_os_descs_ext_prop_name_avail =
2817 vla_ptr(vlabuf, d, ext_prop_name);
2818 ffs->ms_os_descs_ext_prop_data_avail =
2819 vla_ptr(vlabuf, d, ext_prop_data);
2821 /* Copy descriptors */
2822 memcpy(vla_ptr(vlabuf, d, raw_descs), ffs->raw_descs,
2823 ffs->raw_descs_length);
2825 memset(vla_ptr(vlabuf, d, inums), 0xff, d_inums__sz);
2826 eps_ptr = vla_ptr(vlabuf, d, eps);
2827 for (i = 0; i < ffs->eps_count; i++)
2828 eps_ptr[i].num = -1;
2831 * d_eps == vlabuf, func->eps used to kfree vlabuf later
2833 func->eps = vla_ptr(vlabuf, d, eps);
2834 func->interfaces_nums = vla_ptr(vlabuf, d, inums);
2837 * Go through all the endpoint descriptors and allocate
2838 * endpoints first, so that later we can rewrite the endpoint
2839 * numbers without worrying that it may be described later on.
2842 func->function.fs_descriptors = vla_ptr(vlabuf, d, fs_descs);
2843 fs_len = ffs_do_descs(ffs->fs_descs_count,
2844 vla_ptr(vlabuf, d, raw_descs),
2846 __ffs_func_bind_do_descs, func);
2847 if (unlikely(fs_len < 0)) {
2856 func->function.hs_descriptors = vla_ptr(vlabuf, d, hs_descs);
2857 hs_len = ffs_do_descs(ffs->hs_descs_count,
2858 vla_ptr(vlabuf, d, raw_descs) + fs_len,
2859 d_raw_descs__sz - fs_len,
2860 __ffs_func_bind_do_descs, func);
2861 if (unlikely(hs_len < 0)) {
2869 if (likely(super)) {
2870 func->function.ss_descriptors = vla_ptr(vlabuf, d, ss_descs);
2871 ss_len = ffs_do_descs(ffs->ss_descs_count,
2872 vla_ptr(vlabuf, d, raw_descs) + fs_len + hs_len,
2873 d_raw_descs__sz - fs_len - hs_len,
2874 __ffs_func_bind_do_descs, func);
2875 if (unlikely(ss_len < 0)) {
2884 * Now handle interface numbers allocation and interface and
2885 * endpoint numbers rewriting. We can do that in one go
2888 ret = ffs_do_descs(ffs->fs_descs_count +
2889 (high ? ffs->hs_descs_count : 0) +
2890 (super ? ffs->ss_descs_count : 0),
2891 vla_ptr(vlabuf, d, raw_descs), d_raw_descs__sz,
2892 __ffs_func_bind_do_nums, func);
2893 if (unlikely(ret < 0))
2896 func->function.os_desc_table = vla_ptr(vlabuf, d, os_desc_table);
2897 if (c->cdev->use_os_string)
2898 for (i = 0; i < ffs->interfaces_count; ++i) {
2899 struct usb_os_desc *desc;
2901 desc = func->function.os_desc_table[i].os_desc =
2902 vla_ptr(vlabuf, d, os_desc) +
2903 i * sizeof(struct usb_os_desc);
2904 desc->ext_compat_id =
2905 vla_ptr(vlabuf, d, ext_compat) + i * 16;
2906 INIT_LIST_HEAD(&desc->ext_prop);
2908 ret = ffs_do_os_descs(ffs->ms_os_descs_count,
2909 vla_ptr(vlabuf, d, raw_descs) +
2910 fs_len + hs_len + ss_len,
2911 d_raw_descs__sz - fs_len - hs_len - ss_len,
2912 __ffs_func_bind_do_os_desc, func);
2913 if (unlikely(ret < 0))
2915 func->function.os_desc_n =
2916 c->cdev->use_os_string ? ffs->interfaces_count : 0;
2918 /* And we're done */
2919 ffs_event_add(ffs, FUNCTIONFS_BIND);
2923 /* XXX Do we need to release all claimed endpoints here? */
2927 static int ffs_func_bind(struct usb_configuration *c,
2928 struct usb_function *f)
2930 struct f_fs_opts *ffs_opts = ffs_do_functionfs_bind(f, c);
2931 struct ffs_function *func = ffs_func_from_usb(f);
2934 if (IS_ERR(ffs_opts))
2935 return PTR_ERR(ffs_opts);
2937 ret = _ffs_func_bind(c, f);
2938 if (ret && !--ffs_opts->refcnt)
2939 functionfs_unbind(func->ffs);
2945 /* Other USB function hooks *************************************************/
2947 static void ffs_reset_work(struct work_struct *work)
2949 struct ffs_data *ffs = container_of(work,
2950 struct ffs_data, reset_work);
2951 ffs_data_reset(ffs);
2954 static int ffs_func_set_alt(struct usb_function *f,
2955 unsigned interface, unsigned alt)
2957 struct ffs_function *func = ffs_func_from_usb(f);
2958 struct ffs_data *ffs = func->ffs;
2961 if (alt != (unsigned)-1) {
2962 intf = ffs_func_revmap_intf(func, interface);
2963 if (unlikely(intf < 0))
2968 ffs_func_eps_disable(ffs->func);
2970 if (ffs->state == FFS_DEACTIVATED) {
2971 ffs->state = FFS_CLOSING;
2972 INIT_WORK(&ffs->reset_work, ffs_reset_work);
2973 schedule_work(&ffs->reset_work);
2977 if (ffs->state != FFS_ACTIVE)
2980 if (alt == (unsigned)-1) {
2982 ffs_event_add(ffs, FUNCTIONFS_DISABLE);
2987 ret = ffs_func_eps_enable(func);
2988 if (likely(ret >= 0))
2989 ffs_event_add(ffs, FUNCTIONFS_ENABLE);
2993 static void ffs_func_disable(struct usb_function *f)
2995 ffs_func_set_alt(f, 0, (unsigned)-1);
2998 static int ffs_func_setup(struct usb_function *f,
2999 const struct usb_ctrlrequest *creq)
3001 struct ffs_function *func = ffs_func_from_usb(f);
3002 struct ffs_data *ffs = func->ffs;
3003 unsigned long flags;
3008 pr_vdebug("creq->bRequestType = %02x\n", creq->bRequestType);
3009 pr_vdebug("creq->bRequest = %02x\n", creq->bRequest);
3010 pr_vdebug("creq->wValue = %04x\n", le16_to_cpu(creq->wValue));
3011 pr_vdebug("creq->wIndex = %04x\n", le16_to_cpu(creq->wIndex));
3012 pr_vdebug("creq->wLength = %04x\n", le16_to_cpu(creq->wLength));
3015 * Most requests directed to interface go through here
3016 * (notable exceptions are set/get interface) so we need to
3017 * handle them. All other either handled by composite or
3018 * passed to usb_configuration->setup() (if one is set). No
3019 * matter, we will handle requests directed to endpoint here
3020 * as well (as it's straightforward) but what to do with any
3023 if (ffs->state != FFS_ACTIVE)
3026 switch (creq->bRequestType & USB_RECIP_MASK) {
3027 case USB_RECIP_INTERFACE:
3028 ret = ffs_func_revmap_intf(func, le16_to_cpu(creq->wIndex));
3029 if (unlikely(ret < 0))
3033 case USB_RECIP_ENDPOINT:
3034 ret = ffs_func_revmap_ep(func, le16_to_cpu(creq->wIndex));
3035 if (unlikely(ret < 0))
3037 if (func->ffs->user_flags & FUNCTIONFS_VIRTUAL_ADDR)
3038 ret = func->ffs->eps_addrmap[ret];
3045 spin_lock_irqsave(&ffs->ev.waitq.lock, flags);
3046 ffs->ev.setup = *creq;
3047 ffs->ev.setup.wIndex = cpu_to_le16(ret);
3048 __ffs_event_add(ffs, FUNCTIONFS_SETUP);
3049 spin_unlock_irqrestore(&ffs->ev.waitq.lock, flags);
3051 return creq->wLength == 0 ? USB_GADGET_DELAYED_STATUS : 0;
3054 static void ffs_func_suspend(struct usb_function *f)
3057 ffs_event_add(ffs_func_from_usb(f)->ffs, FUNCTIONFS_SUSPEND);
3060 static void ffs_func_resume(struct usb_function *f)
3063 ffs_event_add(ffs_func_from_usb(f)->ffs, FUNCTIONFS_RESUME);
3067 /* Endpoint and interface numbers reverse mapping ***************************/
3069 static int ffs_func_revmap_ep(struct ffs_function *func, u8 num)
3071 num = func->eps_revmap[num & USB_ENDPOINT_NUMBER_MASK];
3072 return num ? num : -EDOM;
3075 static int ffs_func_revmap_intf(struct ffs_function *func, u8 intf)
3077 short *nums = func->interfaces_nums;
3078 unsigned count = func->ffs->interfaces_count;
3080 for (; count; --count, ++nums) {
3081 if (*nums >= 0 && *nums == intf)
3082 return nums - func->interfaces_nums;
3089 /* Devices management *******************************************************/
3091 static LIST_HEAD(ffs_devices);
3093 static struct ffs_dev *_ffs_do_find_dev(const char *name)
3095 struct ffs_dev *dev;
3097 list_for_each_entry(dev, &ffs_devices, entry) {
3098 if (!dev->name || !name)
3100 if (strcmp(dev->name, name) == 0)
3108 * ffs_lock must be taken by the caller of this function
3110 static struct ffs_dev *_ffs_get_single_dev(void)
3112 struct ffs_dev *dev;
3114 if (list_is_singular(&ffs_devices)) {
3115 dev = list_first_entry(&ffs_devices, struct ffs_dev, entry);
3124 * ffs_lock must be taken by the caller of this function
3126 static struct ffs_dev *_ffs_find_dev(const char *name)
3128 struct ffs_dev *dev;
3130 dev = _ffs_get_single_dev();
3134 return _ffs_do_find_dev(name);
3137 /* Configfs support *********************************************************/
3139 static inline struct f_fs_opts *to_ffs_opts(struct config_item *item)
3141 return container_of(to_config_group(item), struct f_fs_opts,
3145 static void ffs_attr_release(struct config_item *item)
3147 struct f_fs_opts *opts = to_ffs_opts(item);
3149 usb_put_function_instance(&opts->func_inst);
3152 static struct configfs_item_operations ffs_item_ops = {
3153 .release = ffs_attr_release,
3156 static struct config_item_type ffs_func_type = {
3157 .ct_item_ops = &ffs_item_ops,
3158 .ct_owner = THIS_MODULE,
3162 /* Function registration interface ******************************************/
3164 static void ffs_free_inst(struct usb_function_instance *f)
3166 struct f_fs_opts *opts;
3168 opts = to_f_fs_opts(f);
3170 _ffs_free_dev(opts->dev);
3175 #define MAX_INST_NAME_LEN 40
3177 static int ffs_set_inst_name(struct usb_function_instance *fi, const char *name)
3179 struct f_fs_opts *opts;
3184 name_len = strlen(name) + 1;
3185 if (name_len > MAX_INST_NAME_LEN)
3186 return -ENAMETOOLONG;
3188 ptr = kstrndup(name, name_len, GFP_KERNEL);
3192 opts = to_f_fs_opts(fi);
3197 tmp = opts->dev->name_allocated ? opts->dev->name : NULL;
3198 ret = _ffs_name_dev(opts->dev, ptr);
3204 opts->dev->name_allocated = true;
3213 static struct usb_function_instance *ffs_alloc_inst(void)
3215 struct f_fs_opts *opts;
3216 struct ffs_dev *dev;
3218 opts = kzalloc(sizeof(*opts), GFP_KERNEL);
3220 return ERR_PTR(-ENOMEM);
3222 opts->func_inst.set_inst_name = ffs_set_inst_name;
3223 opts->func_inst.free_func_inst = ffs_free_inst;
3225 dev = _ffs_alloc_dev();
3229 return ERR_CAST(dev);
3234 config_group_init_type_name(&opts->func_inst.group, "",
3236 return &opts->func_inst;
3239 static void ffs_free(struct usb_function *f)
3241 kfree(ffs_func_from_usb(f));
3244 static void ffs_func_unbind(struct usb_configuration *c,
3245 struct usb_function *f)
3247 struct ffs_function *func = ffs_func_from_usb(f);
3248 struct ffs_data *ffs = func->ffs;
3249 struct f_fs_opts *opts =
3250 container_of(f->fi, struct f_fs_opts, func_inst);
3251 struct ffs_ep *ep = func->eps;
3252 unsigned count = ffs->eps_count;
3253 unsigned long flags;
3256 if (ffs->func == func) {
3257 ffs_func_eps_disable(func);
3261 if (!--opts->refcnt)
3262 functionfs_unbind(ffs);
3264 /* cleanup after autoconfig */
3265 spin_lock_irqsave(&func->ffs->eps_lock, flags);
3267 if (ep->ep && ep->req)
3268 usb_ep_free_request(ep->ep, ep->req);
3272 spin_unlock_irqrestore(&func->ffs->eps_lock, flags);
3276 * eps, descriptors and interfaces_nums are allocated in the
3277 * same chunk so only one free is required.
3279 func->function.fs_descriptors = NULL;
3280 func->function.hs_descriptors = NULL;
3281 func->function.ss_descriptors = NULL;
3282 func->interfaces_nums = NULL;
3284 ffs_event_add(ffs, FUNCTIONFS_UNBIND);
3287 static struct usb_function *ffs_alloc(struct usb_function_instance *fi)
3289 struct ffs_function *func;
3293 func = kzalloc(sizeof(*func), GFP_KERNEL);
3294 if (unlikely(!func))
3295 return ERR_PTR(-ENOMEM);
3297 func->function.name = "Function FS Gadget";
3299 func->function.bind = ffs_func_bind;
3300 func->function.unbind = ffs_func_unbind;
3301 func->function.set_alt = ffs_func_set_alt;
3302 func->function.disable = ffs_func_disable;
3303 func->function.setup = ffs_func_setup;
3304 func->function.suspend = ffs_func_suspend;
3305 func->function.resume = ffs_func_resume;
3306 func->function.free_func = ffs_free;
3308 return &func->function;
3312 * ffs_lock must be taken by the caller of this function
3314 static struct ffs_dev *_ffs_alloc_dev(void)
3316 struct ffs_dev *dev;
3319 if (_ffs_get_single_dev())
3320 return ERR_PTR(-EBUSY);
3322 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
3324 return ERR_PTR(-ENOMEM);
3326 if (list_empty(&ffs_devices)) {
3327 ret = functionfs_init();
3330 return ERR_PTR(ret);
3334 list_add(&dev->entry, &ffs_devices);
3340 * ffs_lock must be taken by the caller of this function
3341 * The caller is responsible for "name" being available whenever f_fs needs it
3343 static int _ffs_name_dev(struct ffs_dev *dev, const char *name)
3345 struct ffs_dev *existing;
3347 existing = _ffs_do_find_dev(name);
3357 * The caller is responsible for "name" being available whenever f_fs needs it
3359 int ffs_name_dev(struct ffs_dev *dev, const char *name)
3364 ret = _ffs_name_dev(dev, name);
3369 EXPORT_SYMBOL_GPL(ffs_name_dev);
3371 int ffs_single_dev(struct ffs_dev *dev)
3378 if (!list_is_singular(&ffs_devices))
3386 EXPORT_SYMBOL_GPL(ffs_single_dev);
3389 * ffs_lock must be taken by the caller of this function
3391 static void _ffs_free_dev(struct ffs_dev *dev)
3393 list_del(&dev->entry);
3394 if (dev->name_allocated)
3397 if (list_empty(&ffs_devices))
3398 functionfs_cleanup();
3401 static void *ffs_acquire_dev(const char *dev_name)
3403 struct ffs_dev *ffs_dev;
3408 ffs_dev = _ffs_find_dev(dev_name);
3410 ffs_dev = ERR_PTR(-ENOENT);
3411 else if (ffs_dev->mounted)
3412 ffs_dev = ERR_PTR(-EBUSY);
3413 else if (ffs_dev->ffs_acquire_dev_callback &&
3414 ffs_dev->ffs_acquire_dev_callback(ffs_dev))
3415 ffs_dev = ERR_PTR(-ENOENT);
3417 ffs_dev->mounted = true;
3423 static void ffs_release_dev(struct ffs_data *ffs_data)
3425 struct ffs_dev *ffs_dev;
3430 ffs_dev = ffs_data->private_data;
3432 ffs_dev->mounted = false;
3434 if (ffs_dev->ffs_release_dev_callback)
3435 ffs_dev->ffs_release_dev_callback(ffs_dev);
3441 static int ffs_ready(struct ffs_data *ffs)
3443 struct ffs_dev *ffs_obj;
3449 ffs_obj = ffs->private_data;
3454 if (WARN_ON(ffs_obj->desc_ready)) {
3459 ffs_obj->desc_ready = true;
3460 ffs_obj->ffs_data = ffs;
3462 if (ffs_obj->ffs_ready_callback) {
3463 ret = ffs_obj->ffs_ready_callback(ffs);
3468 set_bit(FFS_FL_CALL_CLOSED_CALLBACK, &ffs->flags);
3474 static void ffs_closed(struct ffs_data *ffs)
3476 struct ffs_dev *ffs_obj;
3477 struct f_fs_opts *opts;
3478 struct config_item *ci;
3483 ffs_obj = ffs->private_data;
3487 ffs_obj->desc_ready = false;
3489 if (test_and_clear_bit(FFS_FL_CALL_CLOSED_CALLBACK, &ffs->flags) &&
3490 ffs_obj->ffs_closed_callback)
3491 ffs_obj->ffs_closed_callback(ffs);
3494 opts = ffs_obj->opts;
3498 if (opts->no_configfs || !opts->func_inst.group.cg_item.ci_parent
3499 || !atomic_read(&opts->func_inst.group.cg_item.ci_kref.refcount))
3502 ci = opts->func_inst.group.cg_item.ci_parent->ci_parent;
3505 if (test_bit(FFS_FL_BOUND, &ffs->flags))
3506 unregister_gadget_item(ci);
3512 /* Misc helper functions ****************************************************/
3514 static int ffs_mutex_lock(struct mutex *mutex, unsigned nonblock)
3517 ? likely(mutex_trylock(mutex)) ? 0 : -EAGAIN
3518 : mutex_lock_interruptible(mutex);
3521 static char *ffs_prepare_buffer(const char __user *buf, size_t len)
3528 data = kmalloc(len, GFP_KERNEL);
3529 if (unlikely(!data))
3530 return ERR_PTR(-ENOMEM);
3532 if (unlikely(copy_from_user(data, buf, len))) {
3534 return ERR_PTR(-EFAULT);
3537 pr_vdebug("Buffer from user space:\n");
3538 ffs_dump_mem("", data, len);
3543 DECLARE_USB_FUNCTION_INIT(ffs, ffs_alloc_inst, ffs_alloc);
3544 MODULE_LICENSE("GPL");
3545 MODULE_AUTHOR("Michal Nazarewicz");