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) {
653 ret = copy_to_iter(io_data->buf, ret, &io_data->data);
654 if (ret != io_data->req->actual && iov_iter_count(&io_data->data))
656 unuse_mm(io_data->mm);
659 io_data->kiocb->ki_complete(io_data->kiocb, ret, ret);
661 if (io_data->ffs->ffs_eventfd && !kiocb_has_eventfd)
662 eventfd_signal(io_data->ffs->ffs_eventfd, 1);
664 usb_ep_free_request(io_data->ep, io_data->req);
667 kfree(io_data->to_free);
672 static void ffs_epfile_async_io_complete(struct usb_ep *_ep,
673 struct usb_request *req)
675 struct ffs_io_data *io_data = req->context;
679 INIT_WORK(&io_data->work, ffs_user_copy_worker);
680 schedule_work(&io_data->work);
683 static ssize_t ffs_epfile_io(struct file *file, struct ffs_io_data *io_data)
685 struct ffs_epfile *epfile = file->private_data;
688 ssize_t ret, data_len = -EINVAL;
691 /* Are we still active? */
692 if (WARN_ON(epfile->ffs->state != FFS_ACTIVE)) {
697 /* Wait for endpoint to be enabled */
700 if (file->f_flags & O_NONBLOCK) {
705 ret = wait_event_interruptible(epfile->wait, (ep = epfile->ep));
713 halt = (!io_data->read == !epfile->in);
714 if (halt && epfile->isoc) {
719 /* Allocate & copy */
722 * if we _do_ wait above, the epfile->ffs->gadget might be NULL
723 * before the waiting completes, so do not assign to 'gadget' earlier
725 struct usb_gadget *gadget = epfile->ffs->gadget;
728 spin_lock_irq(&epfile->ffs->eps_lock);
729 /* In the meantime, endpoint got disabled or changed. */
730 if (epfile->ep != ep) {
731 spin_unlock_irq(&epfile->ffs->eps_lock);
734 data_len = iov_iter_count(&io_data->data);
736 * Controller may require buffer size to be aligned to
737 * maxpacketsize of an out endpoint.
740 data_len = usb_ep_align_maybe(gadget, ep->ep, data_len);
741 spin_unlock_irq(&epfile->ffs->eps_lock);
743 data = kmalloc(data_len, GFP_KERNEL);
746 if (!io_data->read) {
747 copied = copy_from_iter(data, data_len, &io_data->data);
748 if (copied != data_len) {
755 /* We will be using request */
756 ret = ffs_mutex_lock(&epfile->mutex, file->f_flags & O_NONBLOCK);
760 spin_lock_irq(&epfile->ffs->eps_lock);
762 if (epfile->ep != ep) {
763 /* In the meantime, endpoint got disabled or changed. */
765 spin_unlock_irq(&epfile->ffs->eps_lock);
768 if (likely(epfile->ep == ep) && !WARN_ON(!ep->ep))
769 usb_ep_set_halt(ep->ep);
770 spin_unlock_irq(&epfile->ffs->eps_lock);
773 /* Fire the request */
774 struct usb_request *req;
777 * Sanity Check: even though data_len can't be used
778 * uninitialized at the time I write this comment, some
779 * compilers complain about this situation.
780 * In order to keep the code clean from warnings, data_len is
781 * being initialized to -EINVAL during its declaration, which
782 * means we can't rely on compiler anymore to warn no future
783 * changes won't result in data_len being used uninitialized.
784 * For such reason, we're adding this redundant sanity check
787 if (unlikely(data_len == -EINVAL)) {
788 WARN(1, "%s: data_len == -EINVAL\n", __func__);
794 req = usb_ep_alloc_request(ep->ep, GFP_KERNEL);
799 req->length = data_len;
802 io_data->ep = ep->ep;
804 io_data->ffs = epfile->ffs;
806 req->context = io_data;
807 req->complete = ffs_epfile_async_io_complete;
809 ret = usb_ep_queue(ep->ep, req, GFP_ATOMIC);
811 usb_ep_free_request(ep->ep, req);
816 spin_unlock_irq(&epfile->ffs->eps_lock);
818 DECLARE_COMPLETION_ONSTACK(done);
822 req->length = data_len;
824 req->context = &done;
825 req->complete = ffs_epfile_io_complete;
827 ret = usb_ep_queue(ep->ep, req, GFP_ATOMIC);
829 spin_unlock_irq(&epfile->ffs->eps_lock);
831 if (unlikely(ret < 0)) {
834 wait_for_completion_interruptible(&done))) {
836 usb_ep_dequeue(ep->ep, req);
839 * XXX We may end up silently droping data
840 * here. Since data_len (i.e. req->length) may
841 * be bigger than len (after being rounded up
842 * to maxpacketsize), we may end up with more
843 * data then user space has space for.
846 if (io_data->read && ret > 0) {
847 ret = copy_to_iter(data, ret, &io_data->data);
856 mutex_unlock(&epfile->mutex);
860 spin_unlock_irq(&epfile->ffs->eps_lock);
861 mutex_unlock(&epfile->mutex);
868 ffs_epfile_open(struct inode *inode, struct file *file)
870 struct ffs_epfile *epfile = inode->i_private;
874 if (WARN_ON(epfile->ffs->state != FFS_ACTIVE))
877 file->private_data = epfile;
878 ffs_data_opened(epfile->ffs);
883 static int ffs_aio_cancel(struct kiocb *kiocb)
885 struct ffs_io_data *io_data = kiocb->private;
886 struct ffs_epfile *epfile = kiocb->ki_filp->private_data;
891 spin_lock_irq(&epfile->ffs->eps_lock);
893 if (likely(io_data && io_data->ep && io_data->req))
894 value = usb_ep_dequeue(io_data->ep, io_data->req);
898 spin_unlock_irq(&epfile->ffs->eps_lock);
903 static ssize_t ffs_epfile_write_iter(struct kiocb *kiocb, struct iov_iter *from)
905 struct ffs_io_data io_data, *p = &io_data;
910 if (!is_sync_kiocb(kiocb)) {
911 p = kmalloc(sizeof(io_data), GFP_KERNEL);
927 kiocb_set_cancel_fn(kiocb, ffs_aio_cancel);
929 res = ffs_epfile_io(kiocb->ki_filp, p);
930 if (res == -EIOCBQUEUED)
939 static ssize_t ffs_epfile_read_iter(struct kiocb *kiocb, struct iov_iter *to)
941 struct ffs_io_data io_data, *p = &io_data;
946 if (!is_sync_kiocb(kiocb)) {
947 p = kmalloc(sizeof(io_data), GFP_KERNEL);
958 p->to_free = dup_iter(&p->data, to, GFP_KERNEL);
972 kiocb_set_cancel_fn(kiocb, ffs_aio_cancel);
974 res = ffs_epfile_io(kiocb->ki_filp, p);
975 if (res == -EIOCBQUEUED)
988 ffs_epfile_release(struct inode *inode, struct file *file)
990 struct ffs_epfile *epfile = inode->i_private;
994 ffs_data_closed(epfile->ffs);
999 static long ffs_epfile_ioctl(struct file *file, unsigned code,
1000 unsigned long value)
1002 struct ffs_epfile *epfile = file->private_data;
1007 if (WARN_ON(epfile->ffs->state != FFS_ACTIVE))
1010 spin_lock_irq(&epfile->ffs->eps_lock);
1011 if (likely(epfile->ep)) {
1013 case FUNCTIONFS_FIFO_STATUS:
1014 ret = usb_ep_fifo_status(epfile->ep->ep);
1016 case FUNCTIONFS_FIFO_FLUSH:
1017 usb_ep_fifo_flush(epfile->ep->ep);
1020 case FUNCTIONFS_CLEAR_HALT:
1021 ret = usb_ep_clear_halt(epfile->ep->ep);
1023 case FUNCTIONFS_ENDPOINT_REVMAP:
1024 ret = epfile->ep->num;
1026 case FUNCTIONFS_ENDPOINT_DESC:
1029 struct usb_endpoint_descriptor *desc;
1031 switch (epfile->ffs->gadget->speed) {
1032 case USB_SPEED_SUPER:
1035 case USB_SPEED_HIGH:
1041 desc = epfile->ep->descs[desc_idx];
1043 spin_unlock_irq(&epfile->ffs->eps_lock);
1044 ret = copy_to_user((void *)value, desc, sizeof(*desc));
1055 spin_unlock_irq(&epfile->ffs->eps_lock);
1060 static const struct file_operations ffs_epfile_operations = {
1061 .llseek = no_llseek,
1063 .open = ffs_epfile_open,
1064 .write_iter = ffs_epfile_write_iter,
1065 .read_iter = ffs_epfile_read_iter,
1066 .release = ffs_epfile_release,
1067 .unlocked_ioctl = ffs_epfile_ioctl,
1071 /* File system and super block operations ***********************************/
1074 * Mounting the file system creates a controller file, used first for
1075 * function configuration then later for event monitoring.
1078 static struct inode *__must_check
1079 ffs_sb_make_inode(struct super_block *sb, void *data,
1080 const struct file_operations *fops,
1081 const struct inode_operations *iops,
1082 struct ffs_file_perms *perms)
1084 struct inode *inode;
1088 inode = new_inode(sb);
1090 if (likely(inode)) {
1091 struct timespec current_time = CURRENT_TIME;
1093 inode->i_ino = get_next_ino();
1094 inode->i_mode = perms->mode;
1095 inode->i_uid = perms->uid;
1096 inode->i_gid = perms->gid;
1097 inode->i_atime = current_time;
1098 inode->i_mtime = current_time;
1099 inode->i_ctime = current_time;
1100 inode->i_private = data;
1102 inode->i_fop = fops;
1110 /* Create "regular" file */
1111 static struct dentry *ffs_sb_create_file(struct super_block *sb,
1112 const char *name, void *data,
1113 const struct file_operations *fops)
1115 struct ffs_data *ffs = sb->s_fs_info;
1116 struct dentry *dentry;
1117 struct inode *inode;
1121 dentry = d_alloc_name(sb->s_root, name);
1122 if (unlikely(!dentry))
1125 inode = ffs_sb_make_inode(sb, data, fops, NULL, &ffs->file_perms);
1126 if (unlikely(!inode)) {
1131 d_add(dentry, inode);
1136 static const struct super_operations ffs_sb_operations = {
1137 .statfs = simple_statfs,
1138 .drop_inode = generic_delete_inode,
1141 struct ffs_sb_fill_data {
1142 struct ffs_file_perms perms;
1144 const char *dev_name;
1146 struct ffs_data *ffs_data;
1149 static int ffs_sb_fill(struct super_block *sb, void *_data, int silent)
1151 struct ffs_sb_fill_data *data = _data;
1152 struct inode *inode;
1153 struct ffs_data *ffs = data->ffs_data;
1158 data->ffs_data = NULL;
1159 sb->s_fs_info = ffs;
1160 sb->s_blocksize = PAGE_CACHE_SIZE;
1161 sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
1162 sb->s_magic = FUNCTIONFS_MAGIC;
1163 sb->s_op = &ffs_sb_operations;
1164 sb->s_time_gran = 1;
1167 data->perms.mode = data->root_mode;
1168 inode = ffs_sb_make_inode(sb, NULL,
1169 &simple_dir_operations,
1170 &simple_dir_inode_operations,
1172 sb->s_root = d_make_root(inode);
1173 if (unlikely(!sb->s_root))
1177 if (unlikely(!ffs_sb_create_file(sb, "ep0", ffs,
1178 &ffs_ep0_operations)))
1184 static int ffs_fs_parse_opts(struct ffs_sb_fill_data *data, char *opts)
1188 if (!opts || !*opts)
1192 unsigned long value;
1196 comma = strchr(opts, ',');
1201 eq = strchr(opts, '=');
1202 if (unlikely(!eq)) {
1203 pr_err("'=' missing in %s\n", opts);
1209 if (kstrtoul(eq + 1, 0, &value)) {
1210 pr_err("%s: invalid value: %s\n", opts, eq + 1);
1214 /* Interpret option */
1215 switch (eq - opts) {
1217 if (!memcmp(opts, "no_disconnect", 13))
1218 data->no_disconnect = !!value;
1223 if (!memcmp(opts, "rmode", 5))
1224 data->root_mode = (value & 0555) | S_IFDIR;
1225 else if (!memcmp(opts, "fmode", 5))
1226 data->perms.mode = (value & 0666) | S_IFREG;
1232 if (!memcmp(opts, "mode", 4)) {
1233 data->root_mode = (value & 0555) | S_IFDIR;
1234 data->perms.mode = (value & 0666) | S_IFREG;
1241 if (!memcmp(opts, "uid", 3)) {
1242 data->perms.uid = make_kuid(current_user_ns(), value);
1243 if (!uid_valid(data->perms.uid)) {
1244 pr_err("%s: unmapped value: %lu\n", opts, value);
1247 } else if (!memcmp(opts, "gid", 3)) {
1248 data->perms.gid = make_kgid(current_user_ns(), value);
1249 if (!gid_valid(data->perms.gid)) {
1250 pr_err("%s: unmapped value: %lu\n", opts, value);
1260 pr_err("%s: invalid option\n", opts);
1264 /* Next iteration */
1273 /* "mount -t functionfs dev_name /dev/function" ends up here */
1275 static struct dentry *
1276 ffs_fs_mount(struct file_system_type *t, int flags,
1277 const char *dev_name, void *opts)
1279 struct ffs_sb_fill_data data = {
1281 .mode = S_IFREG | 0600,
1282 .uid = GLOBAL_ROOT_UID,
1283 .gid = GLOBAL_ROOT_GID,
1285 .root_mode = S_IFDIR | 0500,
1286 .no_disconnect = false,
1291 struct ffs_data *ffs;
1295 ret = ffs_fs_parse_opts(&data, opts);
1296 if (unlikely(ret < 0))
1297 return ERR_PTR(ret);
1299 ffs = ffs_data_new();
1301 return ERR_PTR(-ENOMEM);
1302 ffs->file_perms = data.perms;
1303 ffs->no_disconnect = data.no_disconnect;
1305 ffs->dev_name = kstrdup(dev_name, GFP_KERNEL);
1306 if (unlikely(!ffs->dev_name)) {
1308 return ERR_PTR(-ENOMEM);
1311 ffs_dev = ffs_acquire_dev(dev_name);
1312 if (IS_ERR(ffs_dev)) {
1314 return ERR_CAST(ffs_dev);
1316 ffs->private_data = ffs_dev;
1317 data.ffs_data = ffs;
1319 rv = mount_nodev(t, flags, &data, ffs_sb_fill);
1320 if (IS_ERR(rv) && data.ffs_data) {
1321 ffs_release_dev(data.ffs_data);
1322 ffs_data_put(data.ffs_data);
1328 ffs_fs_kill_sb(struct super_block *sb)
1332 kill_litter_super(sb);
1333 if (sb->s_fs_info) {
1334 ffs_release_dev(sb->s_fs_info);
1335 ffs_data_closed(sb->s_fs_info);
1336 ffs_data_put(sb->s_fs_info);
1340 static struct file_system_type ffs_fs_type = {
1341 .owner = THIS_MODULE,
1342 .name = "functionfs",
1343 .mount = ffs_fs_mount,
1344 .kill_sb = ffs_fs_kill_sb,
1346 MODULE_ALIAS_FS("functionfs");
1349 /* Driver's main init/cleanup functions *************************************/
1351 static int functionfs_init(void)
1357 ret = register_filesystem(&ffs_fs_type);
1359 pr_info("file system registered\n");
1361 pr_err("failed registering file system (%d)\n", ret);
1366 static void functionfs_cleanup(void)
1370 pr_info("unloading\n");
1371 unregister_filesystem(&ffs_fs_type);
1375 /* ffs_data and ffs_function construction and destruction code **************/
1377 static void ffs_data_clear(struct ffs_data *ffs);
1378 static void ffs_data_reset(struct ffs_data *ffs);
1380 static void ffs_data_get(struct ffs_data *ffs)
1384 atomic_inc(&ffs->ref);
1387 static void ffs_data_opened(struct ffs_data *ffs)
1391 atomic_inc(&ffs->ref);
1392 if (atomic_add_return(1, &ffs->opened) == 1 &&
1393 ffs->state == FFS_DEACTIVATED) {
1394 ffs->state = FFS_CLOSING;
1395 ffs_data_reset(ffs);
1399 static void ffs_data_put(struct ffs_data *ffs)
1403 if (unlikely(atomic_dec_and_test(&ffs->ref))) {
1404 pr_info("%s(): freeing\n", __func__);
1405 ffs_data_clear(ffs);
1406 BUG_ON(waitqueue_active(&ffs->ev.waitq) ||
1407 waitqueue_active(&ffs->ep0req_completion.wait));
1408 kfree(ffs->dev_name);
1413 static void ffs_data_closed(struct ffs_data *ffs)
1417 if (atomic_dec_and_test(&ffs->opened)) {
1418 if (ffs->no_disconnect) {
1419 ffs->state = FFS_DEACTIVATED;
1421 ffs_epfiles_destroy(ffs->epfiles,
1423 ffs->epfiles = NULL;
1425 if (ffs->setup_state == FFS_SETUP_PENDING)
1426 __ffs_ep0_stall(ffs);
1428 ffs->state = FFS_CLOSING;
1429 ffs_data_reset(ffs);
1432 if (atomic_read(&ffs->opened) < 0) {
1433 ffs->state = FFS_CLOSING;
1434 ffs_data_reset(ffs);
1440 static struct ffs_data *ffs_data_new(void)
1442 struct ffs_data *ffs = kzalloc(sizeof *ffs, GFP_KERNEL);
1448 atomic_set(&ffs->ref, 1);
1449 atomic_set(&ffs->opened, 0);
1450 ffs->state = FFS_READ_DESCRIPTORS;
1451 mutex_init(&ffs->mutex);
1452 spin_lock_init(&ffs->eps_lock);
1453 init_waitqueue_head(&ffs->ev.waitq);
1454 init_completion(&ffs->ep0req_completion);
1456 /* XXX REVISIT need to update it in some places, or do we? */
1457 ffs->ev.can_stall = 1;
1462 static void ffs_data_clear(struct ffs_data *ffs)
1468 BUG_ON(ffs->gadget);
1471 ffs_epfiles_destroy(ffs->epfiles, ffs->eps_count);
1473 if (ffs->ffs_eventfd)
1474 eventfd_ctx_put(ffs->ffs_eventfd);
1476 kfree(ffs->raw_descs_data);
1477 kfree(ffs->raw_strings);
1478 kfree(ffs->stringtabs);
1481 static void ffs_data_reset(struct ffs_data *ffs)
1485 ffs_data_clear(ffs);
1487 ffs->epfiles = NULL;
1488 ffs->raw_descs_data = NULL;
1489 ffs->raw_descs = NULL;
1490 ffs->raw_strings = NULL;
1491 ffs->stringtabs = NULL;
1493 ffs->raw_descs_length = 0;
1494 ffs->fs_descs_count = 0;
1495 ffs->hs_descs_count = 0;
1496 ffs->ss_descs_count = 0;
1498 ffs->strings_count = 0;
1499 ffs->interfaces_count = 0;
1504 ffs->state = FFS_READ_DESCRIPTORS;
1505 ffs->setup_state = FFS_NO_SETUP;
1510 static int functionfs_bind(struct ffs_data *ffs, struct usb_composite_dev *cdev)
1512 struct usb_gadget_strings **lang;
1517 if (WARN_ON(ffs->state != FFS_ACTIVE
1518 || test_and_set_bit(FFS_FL_BOUND, &ffs->flags)))
1521 first_id = usb_string_ids_n(cdev, ffs->strings_count);
1522 if (unlikely(first_id < 0))
1525 ffs->ep0req = usb_ep_alloc_request(cdev->gadget->ep0, GFP_KERNEL);
1526 if (unlikely(!ffs->ep0req))
1528 ffs->ep0req->complete = ffs_ep0_complete;
1529 ffs->ep0req->context = ffs;
1531 lang = ffs->stringtabs;
1533 for (; *lang; ++lang) {
1534 struct usb_string *str = (*lang)->strings;
1536 for (; str->s; ++id, ++str)
1541 ffs->gadget = cdev->gadget;
1546 static void functionfs_unbind(struct ffs_data *ffs)
1550 if (!WARN_ON(!ffs->gadget)) {
1551 usb_ep_free_request(ffs->gadget->ep0, ffs->ep0req);
1554 clear_bit(FFS_FL_BOUND, &ffs->flags);
1559 static int ffs_epfiles_create(struct ffs_data *ffs)
1561 struct ffs_epfile *epfile, *epfiles;
1566 count = ffs->eps_count;
1567 epfiles = kcalloc(count, sizeof(*epfiles), GFP_KERNEL);
1572 for (i = 1; i <= count; ++i, ++epfile) {
1574 mutex_init(&epfile->mutex);
1575 init_waitqueue_head(&epfile->wait);
1576 if (ffs->user_flags & FUNCTIONFS_VIRTUAL_ADDR)
1577 sprintf(epfile->name, "ep%02x", ffs->eps_addrmap[i]);
1579 sprintf(epfile->name, "ep%u", i);
1580 epfile->dentry = ffs_sb_create_file(ffs->sb, epfile->name,
1582 &ffs_epfile_operations);
1583 if (unlikely(!epfile->dentry)) {
1584 ffs_epfiles_destroy(epfiles, i - 1);
1589 ffs->epfiles = epfiles;
1593 static void ffs_epfiles_destroy(struct ffs_epfile *epfiles, unsigned count)
1595 struct ffs_epfile *epfile = epfiles;
1599 for (; count; --count, ++epfile) {
1600 BUG_ON(mutex_is_locked(&epfile->mutex) ||
1601 waitqueue_active(&epfile->wait));
1602 if (epfile->dentry) {
1603 d_delete(epfile->dentry);
1604 dput(epfile->dentry);
1605 epfile->dentry = NULL;
1612 static void ffs_func_eps_disable(struct ffs_function *func)
1614 struct ffs_ep *ep = func->eps;
1615 struct ffs_epfile *epfile = func->ffs->epfiles;
1616 unsigned count = func->ffs->eps_count;
1617 unsigned long flags;
1619 spin_lock_irqsave(&func->ffs->eps_lock, flags);
1621 /* pending requests get nuked */
1623 usb_ep_disable(ep->ep);
1631 spin_unlock_irqrestore(&func->ffs->eps_lock, flags);
1634 static int ffs_func_eps_enable(struct ffs_function *func)
1636 struct ffs_data *ffs = func->ffs;
1637 struct ffs_ep *ep = func->eps;
1638 struct ffs_epfile *epfile = ffs->epfiles;
1639 unsigned count = ffs->eps_count;
1640 unsigned long flags;
1643 spin_lock_irqsave(&func->ffs->eps_lock, flags);
1645 struct usb_endpoint_descriptor *ds;
1648 if (ffs->gadget->speed == USB_SPEED_SUPER)
1650 else if (ffs->gadget->speed == USB_SPEED_HIGH)
1655 /* fall-back to lower speed if desc missing for current speed */
1657 ds = ep->descs[desc_idx];
1658 } while (!ds && --desc_idx >= 0);
1665 ep->ep->driver_data = ep;
1667 ret = usb_ep_enable(ep->ep);
1670 epfile->in = usb_endpoint_dir_in(ds);
1671 epfile->isoc = usb_endpoint_xfer_isoc(ds);
1676 wake_up(&epfile->wait);
1681 spin_unlock_irqrestore(&func->ffs->eps_lock, flags);
1687 /* Parsing and building descriptors and strings *****************************/
1690 * This validates if data pointed by data is a valid USB descriptor as
1691 * well as record how many interfaces, endpoints and strings are
1692 * required by given configuration. Returns address after the
1693 * descriptor or NULL if data is invalid.
1696 enum ffs_entity_type {
1697 FFS_DESCRIPTOR, FFS_INTERFACE, FFS_STRING, FFS_ENDPOINT
1700 enum ffs_os_desc_type {
1701 FFS_OS_DESC, FFS_OS_DESC_EXT_COMPAT, FFS_OS_DESC_EXT_PROP
1704 typedef int (*ffs_entity_callback)(enum ffs_entity_type entity,
1706 struct usb_descriptor_header *desc,
1709 typedef int (*ffs_os_desc_callback)(enum ffs_os_desc_type entity,
1710 struct usb_os_desc_header *h, void *data,
1711 unsigned len, void *priv);
1713 static int __must_check ffs_do_single_desc(char *data, unsigned len,
1714 ffs_entity_callback entity,
1717 struct usb_descriptor_header *_ds = (void *)data;
1723 /* At least two bytes are required: length and type */
1725 pr_vdebug("descriptor too short\n");
1729 /* If we have at least as many bytes as the descriptor takes? */
1730 length = _ds->bLength;
1732 pr_vdebug("descriptor longer then available data\n");
1736 #define __entity_check_INTERFACE(val) 1
1737 #define __entity_check_STRING(val) (val)
1738 #define __entity_check_ENDPOINT(val) ((val) & USB_ENDPOINT_NUMBER_MASK)
1739 #define __entity(type, val) do { \
1740 pr_vdebug("entity " #type "(%02x)\n", (val)); \
1741 if (unlikely(!__entity_check_ ##type(val))) { \
1742 pr_vdebug("invalid entity's value\n"); \
1745 ret = entity(FFS_ ##type, &val, _ds, priv); \
1746 if (unlikely(ret < 0)) { \
1747 pr_debug("entity " #type "(%02x); ret = %d\n", \
1753 /* Parse descriptor depending on type. */
1754 switch (_ds->bDescriptorType) {
1758 case USB_DT_DEVICE_QUALIFIER:
1759 /* function can't have any of those */
1760 pr_vdebug("descriptor reserved for gadget: %d\n",
1761 _ds->bDescriptorType);
1764 case USB_DT_INTERFACE: {
1765 struct usb_interface_descriptor *ds = (void *)_ds;
1766 pr_vdebug("interface descriptor\n");
1767 if (length != sizeof *ds)
1770 __entity(INTERFACE, ds->bInterfaceNumber);
1772 __entity(STRING, ds->iInterface);
1776 case USB_DT_ENDPOINT: {
1777 struct usb_endpoint_descriptor *ds = (void *)_ds;
1778 pr_vdebug("endpoint descriptor\n");
1779 if (length != USB_DT_ENDPOINT_SIZE &&
1780 length != USB_DT_ENDPOINT_AUDIO_SIZE)
1782 __entity(ENDPOINT, ds->bEndpointAddress);
1787 pr_vdebug("hid descriptor\n");
1788 if (length != sizeof(struct hid_descriptor))
1793 if (length != sizeof(struct usb_otg_descriptor))
1797 case USB_DT_INTERFACE_ASSOCIATION: {
1798 struct usb_interface_assoc_descriptor *ds = (void *)_ds;
1799 pr_vdebug("interface association descriptor\n");
1800 if (length != sizeof *ds)
1803 __entity(STRING, ds->iFunction);
1807 case USB_DT_SS_ENDPOINT_COMP:
1808 pr_vdebug("EP SS companion descriptor\n");
1809 if (length != sizeof(struct usb_ss_ep_comp_descriptor))
1813 case USB_DT_OTHER_SPEED_CONFIG:
1814 case USB_DT_INTERFACE_POWER:
1816 case USB_DT_SECURITY:
1817 case USB_DT_CS_RADIO_CONTROL:
1819 pr_vdebug("unimplemented descriptor: %d\n", _ds->bDescriptorType);
1823 /* We should never be here */
1824 pr_vdebug("unknown descriptor: %d\n", _ds->bDescriptorType);
1828 pr_vdebug("invalid length: %d (descriptor %d)\n",
1829 _ds->bLength, _ds->bDescriptorType);
1834 #undef __entity_check_DESCRIPTOR
1835 #undef __entity_check_INTERFACE
1836 #undef __entity_check_STRING
1837 #undef __entity_check_ENDPOINT
1842 static int __must_check ffs_do_descs(unsigned count, char *data, unsigned len,
1843 ffs_entity_callback entity, void *priv)
1845 const unsigned _len = len;
1846 unsigned long num = 0;
1856 /* Record "descriptor" entity */
1857 ret = entity(FFS_DESCRIPTOR, (u8 *)num, (void *)data, priv);
1858 if (unlikely(ret < 0)) {
1859 pr_debug("entity DESCRIPTOR(%02lx); ret = %d\n",
1867 ret = ffs_do_single_desc(data, len, entity, priv);
1868 if (unlikely(ret < 0)) {
1869 pr_debug("%s returns %d\n", __func__, ret);
1879 static int __ffs_data_do_entity(enum ffs_entity_type type,
1880 u8 *valuep, struct usb_descriptor_header *desc,
1883 struct ffs_desc_helper *helper = priv;
1884 struct usb_endpoint_descriptor *d;
1889 case FFS_DESCRIPTOR:
1894 * Interfaces are indexed from zero so if we
1895 * encountered interface "n" then there are at least
1898 if (*valuep >= helper->interfaces_count)
1899 helper->interfaces_count = *valuep + 1;
1904 * Strings are indexed from 1 (0 is magic ;) reserved
1905 * for languages list or some such)
1907 if (*valuep > helper->ffs->strings_count)
1908 helper->ffs->strings_count = *valuep;
1913 helper->eps_count++;
1914 if (helper->eps_count >= 15)
1916 /* Check if descriptors for any speed were already parsed */
1917 if (!helper->ffs->eps_count && !helper->ffs->interfaces_count)
1918 helper->ffs->eps_addrmap[helper->eps_count] =
1919 d->bEndpointAddress;
1920 else if (helper->ffs->eps_addrmap[helper->eps_count] !=
1921 d->bEndpointAddress)
1929 static int __ffs_do_os_desc_header(enum ffs_os_desc_type *next_type,
1930 struct usb_os_desc_header *desc)
1932 u16 bcd_version = le16_to_cpu(desc->bcdVersion);
1933 u16 w_index = le16_to_cpu(desc->wIndex);
1935 if (bcd_version != 1) {
1936 pr_vdebug("unsupported os descriptors version: %d",
1942 *next_type = FFS_OS_DESC_EXT_COMPAT;
1945 *next_type = FFS_OS_DESC_EXT_PROP;
1948 pr_vdebug("unsupported os descriptor type: %d", w_index);
1952 return sizeof(*desc);
1956 * Process all extended compatibility/extended property descriptors
1957 * of a feature descriptor
1959 static int __must_check ffs_do_single_os_desc(char *data, unsigned len,
1960 enum ffs_os_desc_type type,
1962 ffs_os_desc_callback entity,
1964 struct usb_os_desc_header *h)
1967 const unsigned _len = len;
1971 /* loop over all ext compat/ext prop descriptors */
1972 while (feature_count--) {
1973 ret = entity(type, h, data, len, priv);
1974 if (unlikely(ret < 0)) {
1975 pr_debug("bad OS descriptor, type: %d\n", type);
1984 /* Process a number of complete Feature Descriptors (Ext Compat or Ext Prop) */
1985 static int __must_check ffs_do_os_descs(unsigned count,
1986 char *data, unsigned len,
1987 ffs_os_desc_callback entity, void *priv)
1989 const unsigned _len = len;
1990 unsigned long num = 0;
1994 for (num = 0; num < count; ++num) {
1996 enum ffs_os_desc_type type;
1998 struct usb_os_desc_header *desc = (void *)data;
2000 if (len < sizeof(*desc))
2004 * Record "descriptor" entity.
2005 * Process dwLength, bcdVersion, wIndex, get b/wCount.
2006 * Move the data pointer to the beginning of extended
2007 * compatibilities proper or extended properties proper
2008 * portions of the data
2010 if (le32_to_cpu(desc->dwLength) > len)
2013 ret = __ffs_do_os_desc_header(&type, desc);
2014 if (unlikely(ret < 0)) {
2015 pr_debug("entity OS_DESCRIPTOR(%02lx); ret = %d\n",
2020 * 16-bit hex "?? 00" Little Endian looks like 8-bit hex "??"
2022 feature_count = le16_to_cpu(desc->wCount);
2023 if (type == FFS_OS_DESC_EXT_COMPAT &&
2024 (feature_count > 255 || desc->Reserved))
2030 * Process all function/property descriptors
2031 * of this Feature Descriptor
2033 ret = ffs_do_single_os_desc(data, len, type,
2034 feature_count, entity, priv, desc);
2035 if (unlikely(ret < 0)) {
2036 pr_debug("%s returns %d\n", __func__, ret);
2047 * Validate contents of the buffer from userspace related to OS descriptors.
2049 static int __ffs_data_do_os_desc(enum ffs_os_desc_type type,
2050 struct usb_os_desc_header *h, void *data,
2051 unsigned len, void *priv)
2053 struct ffs_data *ffs = priv;
2059 case FFS_OS_DESC_EXT_COMPAT: {
2060 struct usb_ext_compat_desc *d = data;
2063 if (len < sizeof(*d) ||
2064 d->bFirstInterfaceNumber >= ffs->interfaces_count ||
2067 for (i = 0; i < ARRAY_SIZE(d->Reserved2); ++i)
2068 if (d->Reserved2[i])
2071 length = sizeof(struct usb_ext_compat_desc);
2074 case FFS_OS_DESC_EXT_PROP: {
2075 struct usb_ext_prop_desc *d = data;
2079 if (len < sizeof(*d) || h->interface >= ffs->interfaces_count)
2081 length = le32_to_cpu(d->dwSize);
2082 type = le32_to_cpu(d->dwPropertyDataType);
2083 if (type < USB_EXT_PROP_UNICODE ||
2084 type > USB_EXT_PROP_UNICODE_MULTI) {
2085 pr_vdebug("unsupported os descriptor property type: %d",
2089 pnl = le16_to_cpu(d->wPropertyNameLength);
2090 pdl = le32_to_cpu(*(u32 *)((u8 *)data + 10 + pnl));
2091 if (length != 14 + pnl + pdl) {
2092 pr_vdebug("invalid os descriptor length: %d pnl:%d pdl:%d (descriptor %d)\n",
2093 length, pnl, pdl, type);
2096 ++ffs->ms_os_descs_ext_prop_count;
2097 /* property name reported to the host as "WCHAR"s */
2098 ffs->ms_os_descs_ext_prop_name_len += pnl * 2;
2099 ffs->ms_os_descs_ext_prop_data_len += pdl;
2103 pr_vdebug("unknown descriptor: %d\n", type);
2109 static int __ffs_data_got_descs(struct ffs_data *ffs,
2110 char *const _data, size_t len)
2112 char *data = _data, *raw_descs;
2113 unsigned os_descs_count = 0, counts[3], flags;
2114 int ret = -EINVAL, i;
2115 struct ffs_desc_helper helper;
2119 if (get_unaligned_le32(data + 4) != len)
2122 switch (get_unaligned_le32(data)) {
2123 case FUNCTIONFS_DESCRIPTORS_MAGIC:
2124 flags = FUNCTIONFS_HAS_FS_DESC | FUNCTIONFS_HAS_HS_DESC;
2128 case FUNCTIONFS_DESCRIPTORS_MAGIC_V2:
2129 flags = get_unaligned_le32(data + 8);
2130 ffs->user_flags = flags;
2131 if (flags & ~(FUNCTIONFS_HAS_FS_DESC |
2132 FUNCTIONFS_HAS_HS_DESC |
2133 FUNCTIONFS_HAS_SS_DESC |
2134 FUNCTIONFS_HAS_MS_OS_DESC |
2135 FUNCTIONFS_VIRTUAL_ADDR |
2136 FUNCTIONFS_EVENTFD)) {
2147 if (flags & FUNCTIONFS_EVENTFD) {
2151 eventfd_ctx_fdget((int)get_unaligned_le32(data));
2152 if (IS_ERR(ffs->ffs_eventfd)) {
2153 ret = PTR_ERR(ffs->ffs_eventfd);
2154 ffs->ffs_eventfd = NULL;
2161 /* Read fs_count, hs_count and ss_count (if present) */
2162 for (i = 0; i < 3; ++i) {
2163 if (!(flags & (1 << i))) {
2165 } else if (len < 4) {
2168 counts[i] = get_unaligned_le32(data);
2173 if (flags & (1 << i)) {
2174 os_descs_count = get_unaligned_le32(data);
2179 /* Read descriptors */
2182 for (i = 0; i < 3; ++i) {
2185 helper.interfaces_count = 0;
2186 helper.eps_count = 0;
2187 ret = ffs_do_descs(counts[i], data, len,
2188 __ffs_data_do_entity, &helper);
2191 if (!ffs->eps_count && !ffs->interfaces_count) {
2192 ffs->eps_count = helper.eps_count;
2193 ffs->interfaces_count = helper.interfaces_count;
2195 if (ffs->eps_count != helper.eps_count) {
2199 if (ffs->interfaces_count != helper.interfaces_count) {
2207 if (os_descs_count) {
2208 ret = ffs_do_os_descs(os_descs_count, data, len,
2209 __ffs_data_do_os_desc, ffs);
2216 if (raw_descs == data || len) {
2221 ffs->raw_descs_data = _data;
2222 ffs->raw_descs = raw_descs;
2223 ffs->raw_descs_length = data - raw_descs;
2224 ffs->fs_descs_count = counts[0];
2225 ffs->hs_descs_count = counts[1];
2226 ffs->ss_descs_count = counts[2];
2227 ffs->ms_os_descs_count = os_descs_count;
2236 static int __ffs_data_got_strings(struct ffs_data *ffs,
2237 char *const _data, size_t len)
2239 u32 str_count, needed_count, lang_count;
2240 struct usb_gadget_strings **stringtabs, *t;
2241 struct usb_string *strings, *s;
2242 const char *data = _data;
2246 if (unlikely(get_unaligned_le32(data) != FUNCTIONFS_STRINGS_MAGIC ||
2247 get_unaligned_le32(data + 4) != len))
2249 str_count = get_unaligned_le32(data + 8);
2250 lang_count = get_unaligned_le32(data + 12);
2252 /* if one is zero the other must be zero */
2253 if (unlikely(!str_count != !lang_count))
2256 /* Do we have at least as many strings as descriptors need? */
2257 needed_count = ffs->strings_count;
2258 if (unlikely(str_count < needed_count))
2262 * If we don't need any strings just return and free all
2265 if (!needed_count) {
2270 /* Allocate everything in one chunk so there's less maintenance. */
2274 vla_item(d, struct usb_gadget_strings *, stringtabs,
2276 vla_item(d, struct usb_gadget_strings, stringtab, lang_count);
2277 vla_item(d, struct usb_string, strings,
2278 lang_count*(needed_count+1));
2280 char *vlabuf = kmalloc(vla_group_size(d), GFP_KERNEL);
2282 if (unlikely(!vlabuf)) {
2287 /* Initialize the VLA pointers */
2288 stringtabs = vla_ptr(vlabuf, d, stringtabs);
2289 t = vla_ptr(vlabuf, d, stringtab);
2292 *stringtabs++ = t++;
2296 /* stringtabs = vlabuf = d_stringtabs for later kfree */
2297 stringtabs = vla_ptr(vlabuf, d, stringtabs);
2298 t = vla_ptr(vlabuf, d, stringtab);
2299 s = vla_ptr(vlabuf, d, strings);
2303 /* For each language */
2307 do { /* lang_count > 0 so we can use do-while */
2308 unsigned needed = needed_count;
2310 if (unlikely(len < 3))
2312 t->language = get_unaligned_le16(data);
2319 /* For each string */
2320 do { /* str_count > 0 so we can use do-while */
2321 size_t length = strnlen(data, len);
2323 if (unlikely(length == len))
2327 * User may provide more strings then we need,
2328 * if that's the case we simply ignore the
2331 if (likely(needed)) {
2333 * s->id will be set while adding
2334 * function to configuration so for
2335 * now just leave garbage here.
2344 } while (--str_count);
2346 s->id = 0; /* terminator */
2350 } while (--lang_count);
2352 /* Some garbage left? */
2357 ffs->stringtabs = stringtabs;
2358 ffs->raw_strings = _data;
2370 /* Events handling and management *******************************************/
2372 static void __ffs_event_add(struct ffs_data *ffs,
2373 enum usb_functionfs_event_type type)
2375 enum usb_functionfs_event_type rem_type1, rem_type2 = type;
2379 * Abort any unhandled setup
2381 * We do not need to worry about some cmpxchg() changing value
2382 * of ffs->setup_state without holding the lock because when
2383 * state is FFS_SETUP_PENDING cmpxchg() in several places in
2384 * the source does nothing.
2386 if (ffs->setup_state == FFS_SETUP_PENDING)
2387 ffs->setup_state = FFS_SETUP_CANCELLED;
2390 * Logic of this function guarantees that there are at most four pending
2391 * evens on ffs->ev.types queue. This is important because the queue
2392 * has space for four elements only and __ffs_ep0_read_events function
2393 * depends on that limit as well. If more event types are added, those
2394 * limits have to be revisited or guaranteed to still hold.
2397 case FUNCTIONFS_RESUME:
2398 rem_type2 = FUNCTIONFS_SUSPEND;
2400 case FUNCTIONFS_SUSPEND:
2401 case FUNCTIONFS_SETUP:
2403 /* Discard all similar events */
2406 case FUNCTIONFS_BIND:
2407 case FUNCTIONFS_UNBIND:
2408 case FUNCTIONFS_DISABLE:
2409 case FUNCTIONFS_ENABLE:
2410 /* Discard everything other then power management. */
2411 rem_type1 = FUNCTIONFS_SUSPEND;
2412 rem_type2 = FUNCTIONFS_RESUME;
2417 WARN(1, "%d: unknown event, this should not happen\n", type);
2422 u8 *ev = ffs->ev.types, *out = ev;
2423 unsigned n = ffs->ev.count;
2424 for (; n; --n, ++ev)
2425 if ((*ev == rem_type1 || *ev == rem_type2) == neg)
2428 pr_vdebug("purging event %d\n", *ev);
2429 ffs->ev.count = out - ffs->ev.types;
2432 pr_vdebug("adding event %d\n", type);
2433 ffs->ev.types[ffs->ev.count++] = type;
2434 wake_up_locked(&ffs->ev.waitq);
2435 if (ffs->ffs_eventfd)
2436 eventfd_signal(ffs->ffs_eventfd, 1);
2439 static void ffs_event_add(struct ffs_data *ffs,
2440 enum usb_functionfs_event_type type)
2442 unsigned long flags;
2443 spin_lock_irqsave(&ffs->ev.waitq.lock, flags);
2444 __ffs_event_add(ffs, type);
2445 spin_unlock_irqrestore(&ffs->ev.waitq.lock, flags);
2448 /* Bind/unbind USB function hooks *******************************************/
2450 static int ffs_ep_addr2idx(struct ffs_data *ffs, u8 endpoint_address)
2454 for (i = 1; i < ARRAY_SIZE(ffs->eps_addrmap); ++i)
2455 if (ffs->eps_addrmap[i] == endpoint_address)
2460 static int __ffs_func_bind_do_descs(enum ffs_entity_type type, u8 *valuep,
2461 struct usb_descriptor_header *desc,
2464 struct usb_endpoint_descriptor *ds = (void *)desc;
2465 struct ffs_function *func = priv;
2466 struct ffs_ep *ffs_ep;
2467 unsigned ep_desc_id;
2469 static const char *speed_names[] = { "full", "high", "super" };
2471 if (type != FFS_DESCRIPTOR)
2475 * If ss_descriptors is not NULL, we are reading super speed
2476 * descriptors; if hs_descriptors is not NULL, we are reading high
2477 * speed descriptors; otherwise, we are reading full speed
2480 if (func->function.ss_descriptors) {
2482 func->function.ss_descriptors[(long)valuep] = desc;
2483 } else if (func->function.hs_descriptors) {
2485 func->function.hs_descriptors[(long)valuep] = desc;
2488 func->function.fs_descriptors[(long)valuep] = desc;
2491 if (!desc || desc->bDescriptorType != USB_DT_ENDPOINT)
2494 idx = ffs_ep_addr2idx(func->ffs, ds->bEndpointAddress) - 1;
2498 ffs_ep = func->eps + idx;
2500 if (unlikely(ffs_ep->descs[ep_desc_id])) {
2501 pr_err("two %sspeed descriptors for EP %d\n",
2502 speed_names[ep_desc_id],
2503 ds->bEndpointAddress & USB_ENDPOINT_NUMBER_MASK);
2506 ffs_ep->descs[ep_desc_id] = ds;
2508 ffs_dump_mem(": Original ep desc", ds, ds->bLength);
2510 ds->bEndpointAddress = ffs_ep->descs[0]->bEndpointAddress;
2511 if (!ds->wMaxPacketSize)
2512 ds->wMaxPacketSize = ffs_ep->descs[0]->wMaxPacketSize;
2514 struct usb_request *req;
2516 u8 bEndpointAddress;
2519 * We back up bEndpointAddress because autoconfig overwrites
2520 * it with physical endpoint address.
2522 bEndpointAddress = ds->bEndpointAddress;
2523 pr_vdebug("autoconfig\n");
2524 ep = usb_ep_autoconfig(func->gadget, ds);
2527 ep->driver_data = func->eps + idx;
2529 req = usb_ep_alloc_request(ep, GFP_KERNEL);
2535 func->eps_revmap[ds->bEndpointAddress &
2536 USB_ENDPOINT_NUMBER_MASK] = idx + 1;
2538 * If we use virtual address mapping, we restore
2539 * original bEndpointAddress value.
2541 if (func->ffs->user_flags & FUNCTIONFS_VIRTUAL_ADDR)
2542 ds->bEndpointAddress = bEndpointAddress;
2544 ffs_dump_mem(": Rewritten ep desc", ds, ds->bLength);
2549 static int __ffs_func_bind_do_nums(enum ffs_entity_type type, u8 *valuep,
2550 struct usb_descriptor_header *desc,
2553 struct ffs_function *func = priv;
2559 case FFS_DESCRIPTOR:
2560 /* Handled in previous pass by __ffs_func_bind_do_descs() */
2565 if (func->interfaces_nums[idx] < 0) {
2566 int id = usb_interface_id(func->conf, &func->function);
2567 if (unlikely(id < 0))
2569 func->interfaces_nums[idx] = id;
2571 newValue = func->interfaces_nums[idx];
2575 /* String' IDs are allocated when fsf_data is bound to cdev */
2576 newValue = func->ffs->stringtabs[0]->strings[*valuep - 1].id;
2581 * USB_DT_ENDPOINT are handled in
2582 * __ffs_func_bind_do_descs().
2584 if (desc->bDescriptorType == USB_DT_ENDPOINT)
2587 idx = (*valuep & USB_ENDPOINT_NUMBER_MASK) - 1;
2588 if (unlikely(!func->eps[idx].ep))
2592 struct usb_endpoint_descriptor **descs;
2593 descs = func->eps[idx].descs;
2594 newValue = descs[descs[0] ? 0 : 1]->bEndpointAddress;
2599 pr_vdebug("%02x -> %02x\n", *valuep, newValue);
2604 static int __ffs_func_bind_do_os_desc(enum ffs_os_desc_type type,
2605 struct usb_os_desc_header *h, void *data,
2606 unsigned len, void *priv)
2608 struct ffs_function *func = priv;
2612 case FFS_OS_DESC_EXT_COMPAT: {
2613 struct usb_ext_compat_desc *desc = data;
2614 struct usb_os_desc_table *t;
2616 t = &func->function.os_desc_table[desc->bFirstInterfaceNumber];
2617 t->if_id = func->interfaces_nums[desc->bFirstInterfaceNumber];
2618 memcpy(t->os_desc->ext_compat_id, &desc->CompatibleID,
2619 ARRAY_SIZE(desc->CompatibleID) +
2620 ARRAY_SIZE(desc->SubCompatibleID));
2621 length = sizeof(*desc);
2624 case FFS_OS_DESC_EXT_PROP: {
2625 struct usb_ext_prop_desc *desc = data;
2626 struct usb_os_desc_table *t;
2627 struct usb_os_desc_ext_prop *ext_prop;
2628 char *ext_prop_name;
2629 char *ext_prop_data;
2631 t = &func->function.os_desc_table[h->interface];
2632 t->if_id = func->interfaces_nums[h->interface];
2634 ext_prop = func->ffs->ms_os_descs_ext_prop_avail;
2635 func->ffs->ms_os_descs_ext_prop_avail += sizeof(*ext_prop);
2637 ext_prop->type = le32_to_cpu(desc->dwPropertyDataType);
2638 ext_prop->name_len = le16_to_cpu(desc->wPropertyNameLength);
2639 ext_prop->data_len = le32_to_cpu(*(u32 *)
2640 usb_ext_prop_data_len_ptr(data, ext_prop->name_len));
2641 length = ext_prop->name_len + ext_prop->data_len + 14;
2643 ext_prop_name = func->ffs->ms_os_descs_ext_prop_name_avail;
2644 func->ffs->ms_os_descs_ext_prop_name_avail +=
2647 ext_prop_data = func->ffs->ms_os_descs_ext_prop_data_avail;
2648 func->ffs->ms_os_descs_ext_prop_data_avail +=
2650 memcpy(ext_prop_data,
2651 usb_ext_prop_data_ptr(data, ext_prop->name_len),
2652 ext_prop->data_len);
2653 /* unicode data reported to the host as "WCHAR"s */
2654 switch (ext_prop->type) {
2655 case USB_EXT_PROP_UNICODE:
2656 case USB_EXT_PROP_UNICODE_ENV:
2657 case USB_EXT_PROP_UNICODE_LINK:
2658 case USB_EXT_PROP_UNICODE_MULTI:
2659 ext_prop->data_len *= 2;
2662 ext_prop->data = ext_prop_data;
2664 memcpy(ext_prop_name, usb_ext_prop_name_ptr(data),
2665 ext_prop->name_len);
2666 /* property name reported to the host as "WCHAR"s */
2667 ext_prop->name_len *= 2;
2668 ext_prop->name = ext_prop_name;
2670 t->os_desc->ext_prop_len +=
2671 ext_prop->name_len + ext_prop->data_len + 14;
2672 ++t->os_desc->ext_prop_count;
2673 list_add_tail(&ext_prop->entry, &t->os_desc->ext_prop);
2677 pr_vdebug("unknown descriptor: %d\n", type);
2683 static inline struct f_fs_opts *ffs_do_functionfs_bind(struct usb_function *f,
2684 struct usb_configuration *c)
2686 struct ffs_function *func = ffs_func_from_usb(f);
2687 struct f_fs_opts *ffs_opts =
2688 container_of(f->fi, struct f_fs_opts, func_inst);
2694 * Legacy gadget triggers binding in functionfs_ready_callback,
2695 * which already uses locking; taking the same lock here would
2698 * Configfs-enabled gadgets however do need ffs_dev_lock.
2700 if (!ffs_opts->no_configfs)
2702 ret = ffs_opts->dev->desc_ready ? 0 : -ENODEV;
2703 func->ffs = ffs_opts->dev->ffs_data;
2704 if (!ffs_opts->no_configfs)
2707 return ERR_PTR(ret);
2710 func->gadget = c->cdev->gadget;
2713 * in drivers/usb/gadget/configfs.c:configfs_composite_bind()
2714 * configurations are bound in sequence with list_for_each_entry,
2715 * in each configuration its functions are bound in sequence
2716 * with list_for_each_entry, so we assume no race condition
2717 * with regard to ffs_opts->bound access
2719 if (!ffs_opts->refcnt) {
2720 ret = functionfs_bind(func->ffs, c->cdev);
2722 return ERR_PTR(ret);
2725 func->function.strings = func->ffs->stringtabs;
2730 static int _ffs_func_bind(struct usb_configuration *c,
2731 struct usb_function *f)
2733 struct ffs_function *func = ffs_func_from_usb(f);
2734 struct ffs_data *ffs = func->ffs;
2736 const int full = !!func->ffs->fs_descs_count;
2737 const int high = gadget_is_dualspeed(func->gadget) &&
2738 func->ffs->hs_descs_count;
2739 const int super = gadget_is_superspeed(func->gadget) &&
2740 func->ffs->ss_descs_count;
2742 int fs_len, hs_len, ss_len, ret, i;
2744 /* Make it a single chunk, less management later on */
2746 vla_item_with_sz(d, struct ffs_ep, eps, ffs->eps_count);
2747 vla_item_with_sz(d, struct usb_descriptor_header *, fs_descs,
2748 full ? ffs->fs_descs_count + 1 : 0);
2749 vla_item_with_sz(d, struct usb_descriptor_header *, hs_descs,
2750 high ? ffs->hs_descs_count + 1 : 0);
2751 vla_item_with_sz(d, struct usb_descriptor_header *, ss_descs,
2752 super ? ffs->ss_descs_count + 1 : 0);
2753 vla_item_with_sz(d, short, inums, ffs->interfaces_count);
2754 vla_item_with_sz(d, struct usb_os_desc_table, os_desc_table,
2755 c->cdev->use_os_string ? ffs->interfaces_count : 0);
2756 vla_item_with_sz(d, char[16], ext_compat,
2757 c->cdev->use_os_string ? ffs->interfaces_count : 0);
2758 vla_item_with_sz(d, struct usb_os_desc, os_desc,
2759 c->cdev->use_os_string ? ffs->interfaces_count : 0);
2760 vla_item_with_sz(d, struct usb_os_desc_ext_prop, ext_prop,
2761 ffs->ms_os_descs_ext_prop_count);
2762 vla_item_with_sz(d, char, ext_prop_name,
2763 ffs->ms_os_descs_ext_prop_name_len);
2764 vla_item_with_sz(d, char, ext_prop_data,
2765 ffs->ms_os_descs_ext_prop_data_len);
2766 vla_item_with_sz(d, char, raw_descs, ffs->raw_descs_length);
2771 /* Has descriptors only for speeds gadget does not support */
2772 if (unlikely(!(full | high | super)))
2775 /* Allocate a single chunk, less management later on */
2776 vlabuf = kzalloc(vla_group_size(d), GFP_KERNEL);
2777 if (unlikely(!vlabuf))
2780 ffs->ms_os_descs_ext_prop_avail = vla_ptr(vlabuf, d, ext_prop);
2781 ffs->ms_os_descs_ext_prop_name_avail =
2782 vla_ptr(vlabuf, d, ext_prop_name);
2783 ffs->ms_os_descs_ext_prop_data_avail =
2784 vla_ptr(vlabuf, d, ext_prop_data);
2786 /* Copy descriptors */
2787 memcpy(vla_ptr(vlabuf, d, raw_descs), ffs->raw_descs,
2788 ffs->raw_descs_length);
2790 memset(vla_ptr(vlabuf, d, inums), 0xff, d_inums__sz);
2791 for (ret = ffs->eps_count; ret; --ret) {
2794 ptr = vla_ptr(vlabuf, d, eps);
2799 * d_eps == vlabuf, func->eps used to kfree vlabuf later
2801 func->eps = vla_ptr(vlabuf, d, eps);
2802 func->interfaces_nums = vla_ptr(vlabuf, d, inums);
2805 * Go through all the endpoint descriptors and allocate
2806 * endpoints first, so that later we can rewrite the endpoint
2807 * numbers without worrying that it may be described later on.
2810 func->function.fs_descriptors = vla_ptr(vlabuf, d, fs_descs);
2811 fs_len = ffs_do_descs(ffs->fs_descs_count,
2812 vla_ptr(vlabuf, d, raw_descs),
2814 __ffs_func_bind_do_descs, func);
2815 if (unlikely(fs_len < 0)) {
2824 func->function.hs_descriptors = vla_ptr(vlabuf, d, hs_descs);
2825 hs_len = ffs_do_descs(ffs->hs_descs_count,
2826 vla_ptr(vlabuf, d, raw_descs) + fs_len,
2827 d_raw_descs__sz - fs_len,
2828 __ffs_func_bind_do_descs, func);
2829 if (unlikely(hs_len < 0)) {
2837 if (likely(super)) {
2838 func->function.ss_descriptors = vla_ptr(vlabuf, d, ss_descs);
2839 ss_len = ffs_do_descs(ffs->ss_descs_count,
2840 vla_ptr(vlabuf, d, raw_descs) + fs_len + hs_len,
2841 d_raw_descs__sz - fs_len - hs_len,
2842 __ffs_func_bind_do_descs, func);
2843 if (unlikely(ss_len < 0)) {
2852 * Now handle interface numbers allocation and interface and
2853 * endpoint numbers rewriting. We can do that in one go
2856 ret = ffs_do_descs(ffs->fs_descs_count +
2857 (high ? ffs->hs_descs_count : 0) +
2858 (super ? ffs->ss_descs_count : 0),
2859 vla_ptr(vlabuf, d, raw_descs), d_raw_descs__sz,
2860 __ffs_func_bind_do_nums, func);
2861 if (unlikely(ret < 0))
2864 func->function.os_desc_table = vla_ptr(vlabuf, d, os_desc_table);
2865 if (c->cdev->use_os_string)
2866 for (i = 0; i < ffs->interfaces_count; ++i) {
2867 struct usb_os_desc *desc;
2869 desc = func->function.os_desc_table[i].os_desc =
2870 vla_ptr(vlabuf, d, os_desc) +
2871 i * sizeof(struct usb_os_desc);
2872 desc->ext_compat_id =
2873 vla_ptr(vlabuf, d, ext_compat) + i * 16;
2874 INIT_LIST_HEAD(&desc->ext_prop);
2876 ret = ffs_do_os_descs(ffs->ms_os_descs_count,
2877 vla_ptr(vlabuf, d, raw_descs) +
2878 fs_len + hs_len + ss_len,
2879 d_raw_descs__sz - fs_len - hs_len - ss_len,
2880 __ffs_func_bind_do_os_desc, func);
2881 if (unlikely(ret < 0))
2883 func->function.os_desc_n =
2884 c->cdev->use_os_string ? ffs->interfaces_count : 0;
2886 /* And we're done */
2887 ffs_event_add(ffs, FUNCTIONFS_BIND);
2891 /* XXX Do we need to release all claimed endpoints here? */
2895 static int ffs_func_bind(struct usb_configuration *c,
2896 struct usb_function *f)
2898 struct f_fs_opts *ffs_opts = ffs_do_functionfs_bind(f, c);
2899 struct ffs_function *func = ffs_func_from_usb(f);
2902 if (IS_ERR(ffs_opts))
2903 return PTR_ERR(ffs_opts);
2905 ret = _ffs_func_bind(c, f);
2906 if (ret && !--ffs_opts->refcnt)
2907 functionfs_unbind(func->ffs);
2913 /* Other USB function hooks *************************************************/
2915 static void ffs_reset_work(struct work_struct *work)
2917 struct ffs_data *ffs = container_of(work,
2918 struct ffs_data, reset_work);
2919 ffs_data_reset(ffs);
2922 static int ffs_func_set_alt(struct usb_function *f,
2923 unsigned interface, unsigned alt)
2925 struct ffs_function *func = ffs_func_from_usb(f);
2926 struct ffs_data *ffs = func->ffs;
2929 if (alt != (unsigned)-1) {
2930 intf = ffs_func_revmap_intf(func, interface);
2931 if (unlikely(intf < 0))
2936 ffs_func_eps_disable(ffs->func);
2938 if (ffs->state == FFS_DEACTIVATED) {
2939 ffs->state = FFS_CLOSING;
2940 INIT_WORK(&ffs->reset_work, ffs_reset_work);
2941 schedule_work(&ffs->reset_work);
2945 if (ffs->state != FFS_ACTIVE)
2948 if (alt == (unsigned)-1) {
2950 ffs_event_add(ffs, FUNCTIONFS_DISABLE);
2955 ret = ffs_func_eps_enable(func);
2956 if (likely(ret >= 0))
2957 ffs_event_add(ffs, FUNCTIONFS_ENABLE);
2961 static void ffs_func_disable(struct usb_function *f)
2963 ffs_func_set_alt(f, 0, (unsigned)-1);
2966 static int ffs_func_setup(struct usb_function *f,
2967 const struct usb_ctrlrequest *creq)
2969 struct ffs_function *func = ffs_func_from_usb(f);
2970 struct ffs_data *ffs = func->ffs;
2971 unsigned long flags;
2976 pr_vdebug("creq->bRequestType = %02x\n", creq->bRequestType);
2977 pr_vdebug("creq->bRequest = %02x\n", creq->bRequest);
2978 pr_vdebug("creq->wValue = %04x\n", le16_to_cpu(creq->wValue));
2979 pr_vdebug("creq->wIndex = %04x\n", le16_to_cpu(creq->wIndex));
2980 pr_vdebug("creq->wLength = %04x\n", le16_to_cpu(creq->wLength));
2983 * Most requests directed to interface go through here
2984 * (notable exceptions are set/get interface) so we need to
2985 * handle them. All other either handled by composite or
2986 * passed to usb_configuration->setup() (if one is set). No
2987 * matter, we will handle requests directed to endpoint here
2988 * as well (as it's straightforward) but what to do with any
2991 if (ffs->state != FFS_ACTIVE)
2994 switch (creq->bRequestType & USB_RECIP_MASK) {
2995 case USB_RECIP_INTERFACE:
2996 ret = ffs_func_revmap_intf(func, le16_to_cpu(creq->wIndex));
2997 if (unlikely(ret < 0))
3001 case USB_RECIP_ENDPOINT:
3002 ret = ffs_func_revmap_ep(func, le16_to_cpu(creq->wIndex));
3003 if (unlikely(ret < 0))
3005 if (func->ffs->user_flags & FUNCTIONFS_VIRTUAL_ADDR)
3006 ret = func->ffs->eps_addrmap[ret];
3013 spin_lock_irqsave(&ffs->ev.waitq.lock, flags);
3014 ffs->ev.setup = *creq;
3015 ffs->ev.setup.wIndex = cpu_to_le16(ret);
3016 __ffs_event_add(ffs, FUNCTIONFS_SETUP);
3017 spin_unlock_irqrestore(&ffs->ev.waitq.lock, flags);
3022 static void ffs_func_suspend(struct usb_function *f)
3025 ffs_event_add(ffs_func_from_usb(f)->ffs, FUNCTIONFS_SUSPEND);
3028 static void ffs_func_resume(struct usb_function *f)
3031 ffs_event_add(ffs_func_from_usb(f)->ffs, FUNCTIONFS_RESUME);
3035 /* Endpoint and interface numbers reverse mapping ***************************/
3037 static int ffs_func_revmap_ep(struct ffs_function *func, u8 num)
3039 num = func->eps_revmap[num & USB_ENDPOINT_NUMBER_MASK];
3040 return num ? num : -EDOM;
3043 static int ffs_func_revmap_intf(struct ffs_function *func, u8 intf)
3045 short *nums = func->interfaces_nums;
3046 unsigned count = func->ffs->interfaces_count;
3048 for (; count; --count, ++nums) {
3049 if (*nums >= 0 && *nums == intf)
3050 return nums - func->interfaces_nums;
3057 /* Devices management *******************************************************/
3059 static LIST_HEAD(ffs_devices);
3061 static struct ffs_dev *_ffs_do_find_dev(const char *name)
3063 struct ffs_dev *dev;
3065 list_for_each_entry(dev, &ffs_devices, entry) {
3066 if (!dev->name || !name)
3068 if (strcmp(dev->name, name) == 0)
3076 * ffs_lock must be taken by the caller of this function
3078 static struct ffs_dev *_ffs_get_single_dev(void)
3080 struct ffs_dev *dev;
3082 if (list_is_singular(&ffs_devices)) {
3083 dev = list_first_entry(&ffs_devices, struct ffs_dev, entry);
3092 * ffs_lock must be taken by the caller of this function
3094 static struct ffs_dev *_ffs_find_dev(const char *name)
3096 struct ffs_dev *dev;
3098 dev = _ffs_get_single_dev();
3102 return _ffs_do_find_dev(name);
3105 /* Configfs support *********************************************************/
3107 static inline struct f_fs_opts *to_ffs_opts(struct config_item *item)
3109 return container_of(to_config_group(item), struct f_fs_opts,
3113 static void ffs_attr_release(struct config_item *item)
3115 struct f_fs_opts *opts = to_ffs_opts(item);
3117 usb_put_function_instance(&opts->func_inst);
3120 static struct configfs_item_operations ffs_item_ops = {
3121 .release = ffs_attr_release,
3124 static struct config_item_type ffs_func_type = {
3125 .ct_item_ops = &ffs_item_ops,
3126 .ct_owner = THIS_MODULE,
3130 /* Function registration interface ******************************************/
3132 static void ffs_free_inst(struct usb_function_instance *f)
3134 struct f_fs_opts *opts;
3136 opts = to_f_fs_opts(f);
3138 _ffs_free_dev(opts->dev);
3143 #define MAX_INST_NAME_LEN 40
3145 static int ffs_set_inst_name(struct usb_function_instance *fi, const char *name)
3147 struct f_fs_opts *opts;
3152 name_len = strlen(name) + 1;
3153 if (name_len > MAX_INST_NAME_LEN)
3154 return -ENAMETOOLONG;
3156 ptr = kstrndup(name, name_len, GFP_KERNEL);
3160 opts = to_f_fs_opts(fi);
3165 tmp = opts->dev->name_allocated ? opts->dev->name : NULL;
3166 ret = _ffs_name_dev(opts->dev, ptr);
3172 opts->dev->name_allocated = true;
3181 static struct usb_function_instance *ffs_alloc_inst(void)
3183 struct f_fs_opts *opts;
3184 struct ffs_dev *dev;
3186 opts = kzalloc(sizeof(*opts), GFP_KERNEL);
3188 return ERR_PTR(-ENOMEM);
3190 opts->func_inst.set_inst_name = ffs_set_inst_name;
3191 opts->func_inst.free_func_inst = ffs_free_inst;
3193 dev = _ffs_alloc_dev();
3197 return ERR_CAST(dev);
3202 config_group_init_type_name(&opts->func_inst.group, "",
3204 return &opts->func_inst;
3207 static void ffs_free(struct usb_function *f)
3209 kfree(ffs_func_from_usb(f));
3212 static void ffs_func_unbind(struct usb_configuration *c,
3213 struct usb_function *f)
3215 struct ffs_function *func = ffs_func_from_usb(f);
3216 struct ffs_data *ffs = func->ffs;
3217 struct f_fs_opts *opts =
3218 container_of(f->fi, struct f_fs_opts, func_inst);
3219 struct ffs_ep *ep = func->eps;
3220 unsigned count = ffs->eps_count;
3221 unsigned long flags;
3224 if (ffs->func == func) {
3225 ffs_func_eps_disable(func);
3229 if (!--opts->refcnt)
3230 functionfs_unbind(ffs);
3232 /* cleanup after autoconfig */
3233 spin_lock_irqsave(&func->ffs->eps_lock, flags);
3235 if (ep->ep && ep->req)
3236 usb_ep_free_request(ep->ep, ep->req);
3240 spin_unlock_irqrestore(&func->ffs->eps_lock, flags);
3244 * eps, descriptors and interfaces_nums are allocated in the
3245 * same chunk so only one free is required.
3247 func->function.fs_descriptors = NULL;
3248 func->function.hs_descriptors = NULL;
3249 func->function.ss_descriptors = NULL;
3250 func->interfaces_nums = NULL;
3252 ffs_event_add(ffs, FUNCTIONFS_UNBIND);
3255 static struct usb_function *ffs_alloc(struct usb_function_instance *fi)
3257 struct ffs_function *func;
3261 func = kzalloc(sizeof(*func), GFP_KERNEL);
3262 if (unlikely(!func))
3263 return ERR_PTR(-ENOMEM);
3265 func->function.name = "Function FS Gadget";
3267 func->function.bind = ffs_func_bind;
3268 func->function.unbind = ffs_func_unbind;
3269 func->function.set_alt = ffs_func_set_alt;
3270 func->function.disable = ffs_func_disable;
3271 func->function.setup = ffs_func_setup;
3272 func->function.suspend = ffs_func_suspend;
3273 func->function.resume = ffs_func_resume;
3274 func->function.free_func = ffs_free;
3276 return &func->function;
3280 * ffs_lock must be taken by the caller of this function
3282 static struct ffs_dev *_ffs_alloc_dev(void)
3284 struct ffs_dev *dev;
3287 if (_ffs_get_single_dev())
3288 return ERR_PTR(-EBUSY);
3290 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
3292 return ERR_PTR(-ENOMEM);
3294 if (list_empty(&ffs_devices)) {
3295 ret = functionfs_init();
3298 return ERR_PTR(ret);
3302 list_add(&dev->entry, &ffs_devices);
3308 * ffs_lock must be taken by the caller of this function
3309 * The caller is responsible for "name" being available whenever f_fs needs it
3311 static int _ffs_name_dev(struct ffs_dev *dev, const char *name)
3313 struct ffs_dev *existing;
3315 existing = _ffs_do_find_dev(name);
3325 * The caller is responsible for "name" being available whenever f_fs needs it
3327 int ffs_name_dev(struct ffs_dev *dev, const char *name)
3332 ret = _ffs_name_dev(dev, name);
3337 EXPORT_SYMBOL_GPL(ffs_name_dev);
3339 int ffs_single_dev(struct ffs_dev *dev)
3346 if (!list_is_singular(&ffs_devices))
3354 EXPORT_SYMBOL_GPL(ffs_single_dev);
3357 * ffs_lock must be taken by the caller of this function
3359 static void _ffs_free_dev(struct ffs_dev *dev)
3361 list_del(&dev->entry);
3362 if (dev->name_allocated)
3365 if (list_empty(&ffs_devices))
3366 functionfs_cleanup();
3369 static void *ffs_acquire_dev(const char *dev_name)
3371 struct ffs_dev *ffs_dev;
3376 ffs_dev = _ffs_find_dev(dev_name);
3378 ffs_dev = ERR_PTR(-ENOENT);
3379 else if (ffs_dev->mounted)
3380 ffs_dev = ERR_PTR(-EBUSY);
3381 else if (ffs_dev->ffs_acquire_dev_callback &&
3382 ffs_dev->ffs_acquire_dev_callback(ffs_dev))
3383 ffs_dev = ERR_PTR(-ENOENT);
3385 ffs_dev->mounted = true;
3391 static void ffs_release_dev(struct ffs_data *ffs_data)
3393 struct ffs_dev *ffs_dev;
3398 ffs_dev = ffs_data->private_data;
3400 ffs_dev->mounted = false;
3402 if (ffs_dev->ffs_release_dev_callback)
3403 ffs_dev->ffs_release_dev_callback(ffs_dev);
3409 static int ffs_ready(struct ffs_data *ffs)
3411 struct ffs_dev *ffs_obj;
3417 ffs_obj = ffs->private_data;
3422 if (WARN_ON(ffs_obj->desc_ready)) {
3427 ffs_obj->desc_ready = true;
3428 ffs_obj->ffs_data = ffs;
3430 if (ffs_obj->ffs_ready_callback) {
3431 ret = ffs_obj->ffs_ready_callback(ffs);
3436 set_bit(FFS_FL_CALL_CLOSED_CALLBACK, &ffs->flags);
3442 static void ffs_closed(struct ffs_data *ffs)
3444 struct ffs_dev *ffs_obj;
3445 struct f_fs_opts *opts;
3450 ffs_obj = ffs->private_data;
3454 ffs_obj->desc_ready = false;
3456 if (test_and_clear_bit(FFS_FL_CALL_CLOSED_CALLBACK, &ffs->flags) &&
3457 ffs_obj->ffs_closed_callback)
3458 ffs_obj->ffs_closed_callback(ffs);
3461 opts = ffs_obj->opts;
3465 if (opts->no_configfs || !opts->func_inst.group.cg_item.ci_parent
3466 || !atomic_read(&opts->func_inst.group.cg_item.ci_kref.refcount))
3469 unregister_gadget_item(ffs_obj->opts->
3470 func_inst.group.cg_item.ci_parent->ci_parent);
3475 /* Misc helper functions ****************************************************/
3477 static int ffs_mutex_lock(struct mutex *mutex, unsigned nonblock)
3480 ? likely(mutex_trylock(mutex)) ? 0 : -EAGAIN
3481 : mutex_lock_interruptible(mutex);
3484 static char *ffs_prepare_buffer(const char __user *buf, size_t len)
3491 data = kmalloc(len, GFP_KERNEL);
3492 if (unlikely(!data))
3493 return ERR_PTR(-ENOMEM);
3495 if (unlikely(copy_from_user(data, buf, len))) {
3497 return ERR_PTR(-EFAULT);
3500 pr_vdebug("Buffer from user space:\n");
3501 ffs_dump_mem("", data, len);
3506 DECLARE_USB_FUNCTION_INIT(ffs, ffs_alloc_inst, ffs_alloc);
3507 MODULE_LICENSE("GPL");
3508 MODULE_AUTHOR("Michal Nazarewicz");