2 * inode.c -- user mode filesystem api for usb gadget controllers
4 * Copyright (C) 2003-2004 David Brownell
5 * Copyright (C) 2003 Agilent Technologies
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 2 of the License, or
10 * (at your option) any later version.
14 /* #define VERBOSE_DEBUG */
16 #include <linux/init.h>
17 #include <linux/module.h>
19 #include <linux/pagemap.h>
20 #include <linux/uts.h>
21 #include <linux/wait.h>
22 #include <linux/compiler.h>
23 #include <asm/uaccess.h>
24 #include <linux/sched.h>
25 #include <linux/slab.h>
26 #include <linux/poll.h>
27 #include <linux/mmu_context.h>
28 #include <linux/aio.h>
30 #include <linux/device.h>
31 #include <linux/moduleparam.h>
33 #include <linux/usb/gadgetfs.h>
34 #include <linux/usb/gadget.h>
38 * The gadgetfs API maps each endpoint to a file descriptor so that you
39 * can use standard synchronous read/write calls for I/O. There's some
40 * O_NONBLOCK and O_ASYNC/FASYNC style i/o support. Example usermode
41 * drivers show how this works in practice. You can also use AIO to
42 * eliminate I/O gaps between requests, to help when streaming data.
44 * Key parts that must be USB-specific are protocols defining how the
45 * read/write operations relate to the hardware state machines. There
46 * are two types of files. One type is for the device, implementing ep0.
47 * The other type is for each IN or OUT endpoint. In both cases, the
48 * user mode driver must configure the hardware before using it.
50 * - First, dev_config() is called when /dev/gadget/$CHIP is configured
51 * (by writing configuration and device descriptors). Afterwards it
52 * may serve as a source of device events, used to handle all control
53 * requests other than basic enumeration.
55 * - Then, after a SET_CONFIGURATION control request, ep_config() is
56 * called when each /dev/gadget/ep* file is configured (by writing
57 * endpoint descriptors). Afterwards these files are used to write()
58 * IN data or to read() OUT data. To halt the endpoint, a "wrong
59 * direction" request is issued (like reading an IN endpoint).
61 * Unlike "usbfs" the only ioctl()s are for things that are rare, and maybe
62 * not possible on all hardware. For example, precise fault handling with
63 * respect to data left in endpoint fifos after aborted operations; or
64 * selective clearing of endpoint halts, to implement SET_INTERFACE.
67 #define DRIVER_DESC "USB Gadget filesystem"
68 #define DRIVER_VERSION "24 Aug 2004"
70 static const char driver_desc [] = DRIVER_DESC;
71 static const char shortname [] = "gadgetfs";
73 MODULE_DESCRIPTION (DRIVER_DESC);
74 MODULE_AUTHOR ("David Brownell");
75 MODULE_LICENSE ("GPL");
78 /*----------------------------------------------------------------------*/
80 #define GADGETFS_MAGIC 0xaee71ee7
82 /* /dev/gadget/$CHIP represents ep0 and the whole device */
84 /* DISBLED is the initial state.
86 STATE_DEV_DISABLED = 0,
88 /* Only one open() of /dev/gadget/$CHIP; only one file tracks
89 * ep0/device i/o modes and binding to the controller. Driver
90 * must always write descriptors to initialize the device, then
91 * the device becomes UNCONNECTED until enumeration.
95 /* From then on, ep0 fd is in either of two basic modes:
96 * - (UN)CONNECTED: read usb_gadgetfs_event(s) from it
97 * - SETUP: read/write will transfer control data and succeed;
98 * or if "wrong direction", performs protocol stall
100 STATE_DEV_UNCONNECTED,
104 /* UNBOUND means the driver closed ep0, so the device won't be
105 * accessible again (DEV_DISABLED) until all fds are closed.
110 /* enough for the whole queue: most events invalidate others */
116 enum ep0_state state; /* P: lock */
117 struct usb_gadgetfs_event event [N_EVENT];
119 struct fasync_struct *fasync;
122 /* drivers reading ep0 MUST handle control requests (SETUP)
123 * reported that way; else the host will time out.
125 unsigned usermode_setup : 1,
131 unsigned setup_wLength;
133 /* the rest is basically write-once */
134 struct usb_config_descriptor *config, *hs_config;
135 struct usb_device_descriptor *dev;
136 struct usb_request *req;
137 struct usb_gadget *gadget;
138 struct list_head epfiles;
140 wait_queue_head_t wait;
141 struct super_block *sb;
142 struct dentry *dentry;
144 /* except this scratch i/o buffer for ep0 */
148 static inline void get_dev (struct dev_data *data)
150 atomic_inc (&data->count);
153 static void put_dev (struct dev_data *data)
155 if (likely (!atomic_dec_and_test (&data->count)))
157 /* needs no more cleanup */
158 BUG_ON (waitqueue_active (&data->wait));
162 static struct dev_data *dev_new (void)
164 struct dev_data *dev;
166 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
169 dev->state = STATE_DEV_DISABLED;
170 atomic_set (&dev->count, 1);
171 spin_lock_init (&dev->lock);
172 INIT_LIST_HEAD (&dev->epfiles);
173 init_waitqueue_head (&dev->wait);
177 /*----------------------------------------------------------------------*/
179 /* other /dev/gadget/$ENDPOINT files represent endpoints */
181 STATE_EP_DISABLED = 0,
191 struct dev_data *dev;
192 /* must hold dev->lock before accessing ep or req */
194 struct usb_request *req;
197 struct usb_endpoint_descriptor desc, hs_desc;
198 struct list_head epfiles;
199 wait_queue_head_t wait;
200 struct dentry *dentry;
204 static inline void get_ep (struct ep_data *data)
206 atomic_inc (&data->count);
209 static void put_ep (struct ep_data *data)
211 if (likely (!atomic_dec_and_test (&data->count)))
214 /* needs no more cleanup */
215 BUG_ON (!list_empty (&data->epfiles));
216 BUG_ON (waitqueue_active (&data->wait));
220 /*----------------------------------------------------------------------*/
222 /* most "how to use the hardware" policy choices are in userspace:
223 * mapping endpoint roles (which the driver needs) to the capabilities
224 * which the usb controller has. most of those capabilities are exposed
225 * implicitly, starting with the driver name and then endpoint names.
228 static const char *CHIP;
230 /*----------------------------------------------------------------------*/
232 /* NOTE: don't use dev_printk calls before binding to the gadget
233 * at the end of ep0 configuration, or after unbind.
236 /* too wordy: dev_printk(level , &(d)->gadget->dev , fmt , ## args) */
237 #define xprintk(d,level,fmt,args...) \
238 printk(level "%s: " fmt , shortname , ## args)
241 #define DBG(dev,fmt,args...) \
242 xprintk(dev , KERN_DEBUG , fmt , ## args)
244 #define DBG(dev,fmt,args...) \
251 #define VDEBUG(dev,fmt,args...) \
255 #define ERROR(dev,fmt,args...) \
256 xprintk(dev , KERN_ERR , fmt , ## args)
257 #define INFO(dev,fmt,args...) \
258 xprintk(dev , KERN_INFO , fmt , ## args)
261 /*----------------------------------------------------------------------*/
263 /* SYNCHRONOUS ENDPOINT OPERATIONS (bulk/intr/iso)
265 * After opening, configure non-control endpoints. Then use normal
266 * stream read() and write() requests; and maybe ioctl() to get more
267 * precise FIFO status when recovering from cancellation.
270 static void epio_complete (struct usb_ep *ep, struct usb_request *req)
272 struct ep_data *epdata = ep->driver_data;
277 epdata->status = req->status;
279 epdata->status = req->actual;
280 complete ((struct completion *)req->context);
283 /* tasklock endpoint, returning when it's connected.
284 * still need dev->lock to use epdata->ep.
287 get_ready_ep (unsigned f_flags, struct ep_data *epdata)
291 if (f_flags & O_NONBLOCK) {
292 if (!mutex_trylock(&epdata->lock))
294 if (epdata->state != STATE_EP_ENABLED) {
295 mutex_unlock(&epdata->lock);
303 val = mutex_lock_interruptible(&epdata->lock);
307 switch (epdata->state) {
308 case STATE_EP_ENABLED:
310 // case STATE_EP_DISABLED: /* "can't happen" */
311 // case STATE_EP_READY: /* "can't happen" */
312 default: /* error! */
313 pr_debug ("%s: ep %p not available, state %d\n",
314 shortname, epdata, epdata->state);
316 case STATE_EP_UNBOUND: /* clean disconnect */
318 mutex_unlock(&epdata->lock);
324 ep_io (struct ep_data *epdata, void *buf, unsigned len)
326 DECLARE_COMPLETION_ONSTACK (done);
329 spin_lock_irq (&epdata->dev->lock);
330 if (likely (epdata->ep != NULL)) {
331 struct usb_request *req = epdata->req;
333 req->context = &done;
334 req->complete = epio_complete;
337 value = usb_ep_queue (epdata->ep, req, GFP_ATOMIC);
340 spin_unlock_irq (&epdata->dev->lock);
342 if (likely (value == 0)) {
343 value = wait_event_interruptible (done.wait, done.done);
345 spin_lock_irq (&epdata->dev->lock);
346 if (likely (epdata->ep != NULL)) {
347 DBG (epdata->dev, "%s i/o interrupted\n",
349 usb_ep_dequeue (epdata->ep, epdata->req);
350 spin_unlock_irq (&epdata->dev->lock);
352 wait_event (done.wait, done.done);
353 if (epdata->status == -ECONNRESET)
354 epdata->status = -EINTR;
356 spin_unlock_irq (&epdata->dev->lock);
358 DBG (epdata->dev, "endpoint gone\n");
359 epdata->status = -ENODEV;
362 return epdata->status;
368 /* handle a synchronous OUT bulk/intr/iso transfer */
370 ep_read (struct file *fd, char __user *buf, size_t len, loff_t *ptr)
372 struct ep_data *data = fd->private_data;
376 if ((value = get_ready_ep (fd->f_flags, data)) < 0)
379 /* halt any endpoint by doing a "wrong direction" i/o call */
380 if (usb_endpoint_dir_in(&data->desc)) {
381 if (usb_endpoint_xfer_isoc(&data->desc)) {
382 mutex_unlock(&data->lock);
385 DBG (data->dev, "%s halt\n", data->name);
386 spin_lock_irq (&data->dev->lock);
387 if (likely (data->ep != NULL))
388 usb_ep_set_halt (data->ep);
389 spin_unlock_irq (&data->dev->lock);
390 mutex_unlock(&data->lock);
394 /* FIXME readahead for O_NONBLOCK and poll(); careful with ZLPs */
397 kbuf = kmalloc (len, GFP_KERNEL);
398 if (unlikely (!kbuf))
401 value = ep_io (data, kbuf, len);
402 VDEBUG (data->dev, "%s read %zu OUT, status %d\n",
403 data->name, len, (int) value);
404 if (value >= 0 && copy_to_user (buf, kbuf, value))
408 mutex_unlock(&data->lock);
413 /* handle a synchronous IN bulk/intr/iso transfer */
415 ep_write (struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
417 struct ep_data *data = fd->private_data;
421 if ((value = get_ready_ep (fd->f_flags, data)) < 0)
424 /* halt any endpoint by doing a "wrong direction" i/o call */
425 if (!usb_endpoint_dir_in(&data->desc)) {
426 if (usb_endpoint_xfer_isoc(&data->desc)) {
427 mutex_unlock(&data->lock);
430 DBG (data->dev, "%s halt\n", data->name);
431 spin_lock_irq (&data->dev->lock);
432 if (likely (data->ep != NULL))
433 usb_ep_set_halt (data->ep);
434 spin_unlock_irq (&data->dev->lock);
435 mutex_unlock(&data->lock);
439 /* FIXME writebehind for O_NONBLOCK and poll(), qlen = 1 */
442 kbuf = kmalloc (len, GFP_KERNEL);
445 if (copy_from_user (kbuf, buf, len)) {
450 value = ep_io (data, kbuf, len);
451 VDEBUG (data->dev, "%s write %zu IN, status %d\n",
452 data->name, len, (int) value);
454 mutex_unlock(&data->lock);
460 ep_release (struct inode *inode, struct file *fd)
462 struct ep_data *data = fd->private_data;
465 value = mutex_lock_interruptible(&data->lock);
469 /* clean up if this can be reopened */
470 if (data->state != STATE_EP_UNBOUND) {
471 data->state = STATE_EP_DISABLED;
472 data->desc.bDescriptorType = 0;
473 data->hs_desc.bDescriptorType = 0;
474 usb_ep_disable(data->ep);
476 mutex_unlock(&data->lock);
481 static long ep_ioctl(struct file *fd, unsigned code, unsigned long value)
483 struct ep_data *data = fd->private_data;
486 if ((status = get_ready_ep (fd->f_flags, data)) < 0)
489 spin_lock_irq (&data->dev->lock);
490 if (likely (data->ep != NULL)) {
492 case GADGETFS_FIFO_STATUS:
493 status = usb_ep_fifo_status (data->ep);
495 case GADGETFS_FIFO_FLUSH:
496 usb_ep_fifo_flush (data->ep);
498 case GADGETFS_CLEAR_HALT:
499 status = usb_ep_clear_halt (data->ep);
506 spin_unlock_irq (&data->dev->lock);
507 mutex_unlock(&data->lock);
511 /*----------------------------------------------------------------------*/
513 /* ASYNCHRONOUS ENDPOINT I/O OPERATIONS (bulk/intr/iso) */
516 struct usb_request *req;
517 struct ep_data *epdata;
519 struct mm_struct *mm;
520 struct work_struct work;
522 const struct iovec *iv;
523 unsigned long nr_segs;
527 static int ep_aio_cancel(struct kiocb *iocb, struct io_event *e)
529 struct kiocb_priv *priv = iocb->private;
530 struct ep_data *epdata;
534 epdata = priv->epdata;
535 // spin_lock(&epdata->dev->lock);
536 if (likely(epdata && epdata->ep && priv->req))
537 value = usb_ep_dequeue (epdata->ep, priv->req);
540 // spin_unlock(&epdata->dev->lock);
547 static ssize_t ep_copy_to_user(struct kiocb_priv *priv)
553 /* copy stuff into user buffers */
554 total = priv->actual;
557 for (i=0; i < priv->nr_segs; i++) {
558 ssize_t this = min((ssize_t)(priv->iv[i].iov_len), total);
560 if (copy_to_user(priv->iv[i].iov_base, to_copy, this)) {
576 static void ep_user_copy_worker(struct work_struct *work)
578 struct kiocb_priv *priv = container_of(work, struct kiocb_priv, work);
579 struct mm_struct *mm = priv->mm;
580 struct kiocb *iocb = priv->iocb;
584 ret = ep_copy_to_user(priv);
587 /* completing the iocb can drop the ctx and mm, don't touch mm after */
588 aio_complete(iocb, ret, ret);
594 static void ep_aio_complete(struct usb_ep *ep, struct usb_request *req)
596 struct kiocb *iocb = req->context;
597 struct kiocb_priv *priv = iocb->private;
598 struct ep_data *epdata = priv->epdata;
600 /* lock against disconnect (and ideally, cancel) */
601 spin_lock(&epdata->dev->lock);
605 /* if this was a write or a read returning no data then we
606 * don't need to copy anything to userspace, so we can
607 * complete the aio request immediately.
609 if (priv->iv == NULL || unlikely(req->actual == 0)) {
612 iocb->private = NULL;
613 /* aio_complete() reports bytes-transferred _and_ faults */
614 aio_complete(iocb, req->actual ? req->actual : req->status,
617 /* ep_copy_to_user() won't report both; we hide some faults */
618 if (unlikely(0 != req->status))
619 DBG(epdata->dev, "%s fault %d len %d\n",
620 ep->name, req->status, req->actual);
622 priv->buf = req->buf;
623 priv->actual = req->actual;
624 schedule_work(&priv->work);
626 spin_unlock(&epdata->dev->lock);
628 usb_ep_free_request(ep, req);
637 struct ep_data *epdata,
638 const struct iovec *iv,
639 unsigned long nr_segs
642 struct kiocb_priv *priv;
643 struct usb_request *req;
646 priv = kmalloc(sizeof *priv, GFP_KERNEL);
653 iocb->private = priv;
656 priv->nr_segs = nr_segs;
657 INIT_WORK(&priv->work, ep_user_copy_worker);
659 value = get_ready_ep(iocb->ki_filp->f_flags, epdata);
660 if (unlikely(value < 0)) {
665 kiocb_set_cancel_fn(iocb, ep_aio_cancel);
667 priv->epdata = epdata;
669 priv->mm = current->mm; /* mm teardown waits for iocbs in exit_aio() */
671 /* each kiocb is coupled to one usb_request, but we can't
672 * allocate or submit those if the host disconnected.
674 spin_lock_irq(&epdata->dev->lock);
675 if (likely(epdata->ep)) {
676 req = usb_ep_alloc_request(epdata->ep, GFP_ATOMIC);
681 req->complete = ep_aio_complete;
683 value = usb_ep_queue(epdata->ep, req, GFP_ATOMIC);
684 if (unlikely(0 != value))
685 usb_ep_free_request(epdata->ep, req);
690 spin_unlock_irq(&epdata->dev->lock);
692 mutex_unlock(&epdata->lock);
694 if (unlikely(value)) {
698 value = -EIOCBQUEUED;
703 ep_aio_read(struct kiocb *iocb, const struct iovec *iov,
704 unsigned long nr_segs, loff_t o)
706 struct ep_data *epdata = iocb->ki_filp->private_data;
709 if (unlikely(usb_endpoint_dir_in(&epdata->desc)))
712 buf = kmalloc(iocb->ki_left, GFP_KERNEL);
716 return ep_aio_rwtail(iocb, buf, iocb->ki_left, epdata, iov, nr_segs);
720 ep_aio_write(struct kiocb *iocb, const struct iovec *iov,
721 unsigned long nr_segs, loff_t o)
723 struct ep_data *epdata = iocb->ki_filp->private_data;
728 if (unlikely(!usb_endpoint_dir_in(&epdata->desc)))
731 buf = kmalloc(iocb->ki_left, GFP_KERNEL);
735 for (i=0; i < nr_segs; i++) {
736 if (unlikely(copy_from_user(&buf[len], iov[i].iov_base,
737 iov[i].iov_len) != 0)) {
741 len += iov[i].iov_len;
743 return ep_aio_rwtail(iocb, buf, len, epdata, NULL, 0);
746 /*----------------------------------------------------------------------*/
748 /* used after endpoint configuration */
749 static const struct file_operations ep_io_operations = {
750 .owner = THIS_MODULE,
755 .unlocked_ioctl = ep_ioctl,
756 .release = ep_release,
758 .aio_read = ep_aio_read,
759 .aio_write = ep_aio_write,
762 /* ENDPOINT INITIALIZATION
764 * fd = open ("/dev/gadget/$ENDPOINT", O_RDWR)
765 * status = write (fd, descriptors, sizeof descriptors)
767 * That write establishes the endpoint configuration, configuring
768 * the controller to process bulk, interrupt, or isochronous transfers
769 * at the right maxpacket size, and so on.
771 * The descriptors are message type 1, identified by a host order u32
772 * at the beginning of what's written. Descriptor order is: full/low
773 * speed descriptor, then optional high speed descriptor.
776 ep_config (struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
778 struct ep_data *data = fd->private_data;
781 int value, length = len;
783 value = mutex_lock_interruptible(&data->lock);
787 if (data->state != STATE_EP_READY) {
793 if (len < USB_DT_ENDPOINT_SIZE + 4)
796 /* we might need to change message format someday */
797 if (copy_from_user (&tag, buf, 4)) {
801 DBG(data->dev, "config %s, bad tag %d\n", data->name, tag);
807 /* NOTE: audio endpoint extensions not accepted here;
808 * just don't include the extra bytes.
811 /* full/low speed descriptor, then high speed */
812 if (copy_from_user (&data->desc, buf, USB_DT_ENDPOINT_SIZE)) {
815 if (data->desc.bLength != USB_DT_ENDPOINT_SIZE
816 || data->desc.bDescriptorType != USB_DT_ENDPOINT)
818 if (len != USB_DT_ENDPOINT_SIZE) {
819 if (len != 2 * USB_DT_ENDPOINT_SIZE)
821 if (copy_from_user (&data->hs_desc, buf + USB_DT_ENDPOINT_SIZE,
822 USB_DT_ENDPOINT_SIZE)) {
825 if (data->hs_desc.bLength != USB_DT_ENDPOINT_SIZE
826 || data->hs_desc.bDescriptorType
827 != USB_DT_ENDPOINT) {
828 DBG(data->dev, "config %s, bad hs length or type\n",
834 spin_lock_irq (&data->dev->lock);
835 if (data->dev->state == STATE_DEV_UNBOUND) {
838 } else if ((ep = data->ep) == NULL) {
842 switch (data->dev->gadget->speed) {
845 ep->desc = &data->desc;
846 value = usb_ep_enable(ep);
848 data->state = STATE_EP_ENABLED;
851 /* fails if caller didn't provide that descriptor... */
852 ep->desc = &data->hs_desc;
853 value = usb_ep_enable(ep);
855 data->state = STATE_EP_ENABLED;
858 DBG(data->dev, "unconnected, %s init abandoned\n",
863 fd->f_op = &ep_io_operations;
867 spin_unlock_irq (&data->dev->lock);
870 data->desc.bDescriptorType = 0;
871 data->hs_desc.bDescriptorType = 0;
873 mutex_unlock(&data->lock);
884 ep_open (struct inode *inode, struct file *fd)
886 struct ep_data *data = inode->i_private;
889 if (mutex_lock_interruptible(&data->lock) != 0)
891 spin_lock_irq (&data->dev->lock);
892 if (data->dev->state == STATE_DEV_UNBOUND)
894 else if (data->state == STATE_EP_DISABLED) {
896 data->state = STATE_EP_READY;
898 fd->private_data = data;
899 VDEBUG (data->dev, "%s ready\n", data->name);
901 DBG (data->dev, "%s state %d\n",
902 data->name, data->state);
903 spin_unlock_irq (&data->dev->lock);
904 mutex_unlock(&data->lock);
908 /* used before endpoint configuration */
909 static const struct file_operations ep_config_operations = {
910 .owner = THIS_MODULE,
915 .release = ep_release,
918 /*----------------------------------------------------------------------*/
920 /* EP0 IMPLEMENTATION can be partly in userspace.
922 * Drivers that use this facility receive various events, including
923 * control requests the kernel doesn't handle. Drivers that don't
924 * use this facility may be too simple-minded for real applications.
927 static inline void ep0_readable (struct dev_data *dev)
929 wake_up (&dev->wait);
930 kill_fasync (&dev->fasync, SIGIO, POLL_IN);
933 static void clean_req (struct usb_ep *ep, struct usb_request *req)
935 struct dev_data *dev = ep->driver_data;
937 if (req->buf != dev->rbuf) {
939 req->buf = dev->rbuf;
941 req->complete = epio_complete;
942 dev->setup_out_ready = 0;
945 static void ep0_complete (struct usb_ep *ep, struct usb_request *req)
947 struct dev_data *dev = ep->driver_data;
951 /* for control OUT, data must still get to userspace */
952 spin_lock_irqsave(&dev->lock, flags);
953 if (!dev->setup_in) {
954 dev->setup_out_error = (req->status != 0);
955 if (!dev->setup_out_error)
957 dev->setup_out_ready = 1;
961 /* clean up as appropriate */
962 if (free && req->buf != &dev->rbuf)
964 req->complete = epio_complete;
965 spin_unlock_irqrestore(&dev->lock, flags);
968 static int setup_req (struct usb_ep *ep, struct usb_request *req, u16 len)
970 struct dev_data *dev = ep->driver_data;
972 if (dev->setup_out_ready) {
973 DBG (dev, "ep0 request busy!\n");
976 if (len > sizeof (dev->rbuf))
977 req->buf = kmalloc(len, GFP_ATOMIC);
978 if (req->buf == NULL) {
979 req->buf = dev->rbuf;
982 req->complete = ep0_complete;
989 ep0_read (struct file *fd, char __user *buf, size_t len, loff_t *ptr)
991 struct dev_data *dev = fd->private_data;
993 enum ep0_state state;
995 spin_lock_irq (&dev->lock);
997 /* report fd mode change before acting on it */
998 if (dev->setup_abort) {
999 dev->setup_abort = 0;
1004 /* control DATA stage */
1005 if ((state = dev->state) == STATE_DEV_SETUP) {
1007 if (dev->setup_in) { /* stall IN */
1008 VDEBUG(dev, "ep0in stall\n");
1009 (void) usb_ep_set_halt (dev->gadget->ep0);
1011 dev->state = STATE_DEV_CONNECTED;
1013 } else if (len == 0) { /* ack SET_CONFIGURATION etc */
1014 struct usb_ep *ep = dev->gadget->ep0;
1015 struct usb_request *req = dev->req;
1017 if ((retval = setup_req (ep, req, 0)) == 0)
1018 retval = usb_ep_queue (ep, req, GFP_ATOMIC);
1019 dev->state = STATE_DEV_CONNECTED;
1021 /* assume that was SET_CONFIGURATION */
1022 if (dev->current_config) {
1025 if (gadget_is_dualspeed(dev->gadget)
1026 && (dev->gadget->speed
1028 power = dev->hs_config->bMaxPower;
1030 power = dev->config->bMaxPower;
1031 usb_gadget_vbus_draw(dev->gadget, 2 * power);
1034 } else { /* collect OUT data */
1035 if ((fd->f_flags & O_NONBLOCK) != 0
1036 && !dev->setup_out_ready) {
1040 spin_unlock_irq (&dev->lock);
1041 retval = wait_event_interruptible (dev->wait,
1042 dev->setup_out_ready != 0);
1044 /* FIXME state could change from under us */
1045 spin_lock_irq (&dev->lock);
1049 if (dev->state != STATE_DEV_SETUP) {
1050 retval = -ECANCELED;
1053 dev->state = STATE_DEV_CONNECTED;
1055 if (dev->setup_out_error)
1058 len = min (len, (size_t)dev->req->actual);
1059 // FIXME don't call this with the spinlock held ...
1060 if (copy_to_user (buf, dev->req->buf, len))
1064 clean_req (dev->gadget->ep0, dev->req);
1065 /* NOTE userspace can't yet choose to stall */
1071 /* else normal: return event data */
1072 if (len < sizeof dev->event [0]) {
1076 len -= len % sizeof (struct usb_gadgetfs_event);
1077 dev->usermode_setup = 1;
1080 /* return queued events right away */
1081 if (dev->ev_next != 0) {
1084 n = len / sizeof (struct usb_gadgetfs_event);
1085 if (dev->ev_next < n)
1088 /* ep0 i/o has special semantics during STATE_DEV_SETUP */
1089 for (i = 0; i < n; i++) {
1090 if (dev->event [i].type == GADGETFS_SETUP) {
1091 dev->state = STATE_DEV_SETUP;
1096 spin_unlock_irq (&dev->lock);
1097 len = n * sizeof (struct usb_gadgetfs_event);
1098 if (copy_to_user (buf, &dev->event, len))
1103 /* NOTE this doesn't guard against broken drivers;
1104 * concurrent ep0 readers may lose events.
1106 spin_lock_irq (&dev->lock);
1107 if (dev->ev_next > n) {
1108 memmove(&dev->event[0], &dev->event[n],
1109 sizeof (struct usb_gadgetfs_event)
1110 * (dev->ev_next - n));
1113 spin_unlock_irq (&dev->lock);
1117 if (fd->f_flags & O_NONBLOCK) {
1124 DBG (dev, "fail %s, state %d\n", __func__, state);
1127 case STATE_DEV_UNCONNECTED:
1128 case STATE_DEV_CONNECTED:
1129 spin_unlock_irq (&dev->lock);
1130 DBG (dev, "%s wait\n", __func__);
1132 /* wait for events */
1133 retval = wait_event_interruptible (dev->wait,
1137 spin_lock_irq (&dev->lock);
1142 spin_unlock_irq (&dev->lock);
1146 static struct usb_gadgetfs_event *
1147 next_event (struct dev_data *dev, enum usb_gadgetfs_event_type type)
1149 struct usb_gadgetfs_event *event;
1153 /* these events purge the queue */
1154 case GADGETFS_DISCONNECT:
1155 if (dev->state == STATE_DEV_SETUP)
1156 dev->setup_abort = 1;
1158 case GADGETFS_CONNECT:
1161 case GADGETFS_SETUP: /* previous request timed out */
1162 case GADGETFS_SUSPEND: /* same effect */
1163 /* these events can't be repeated */
1164 for (i = 0; i != dev->ev_next; i++) {
1165 if (dev->event [i].type != type)
1167 DBG(dev, "discard old event[%d] %d\n", i, type);
1169 if (i == dev->ev_next)
1171 /* indices start at zero, for simplicity */
1172 memmove (&dev->event [i], &dev->event [i + 1],
1173 sizeof (struct usb_gadgetfs_event)
1174 * (dev->ev_next - i));
1180 VDEBUG(dev, "event[%d] = %d\n", dev->ev_next, type);
1181 event = &dev->event [dev->ev_next++];
1182 BUG_ON (dev->ev_next > N_EVENT);
1183 memset (event, 0, sizeof *event);
1189 ep0_write (struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
1191 struct dev_data *dev = fd->private_data;
1192 ssize_t retval = -ESRCH;
1194 spin_lock_irq (&dev->lock);
1196 /* report fd mode change before acting on it */
1197 if (dev->setup_abort) {
1198 dev->setup_abort = 0;
1201 /* data and/or status stage for control request */
1202 } else if (dev->state == STATE_DEV_SETUP) {
1204 /* IN DATA+STATUS caller makes len <= wLength */
1205 if (dev->setup_in) {
1206 retval = setup_req (dev->gadget->ep0, dev->req, len);
1208 dev->state = STATE_DEV_CONNECTED;
1209 spin_unlock_irq (&dev->lock);
1210 if (copy_from_user (dev->req->buf, buf, len))
1213 if (len < dev->setup_wLength)
1215 retval = usb_ep_queue (
1216 dev->gadget->ep0, dev->req,
1220 spin_lock_irq (&dev->lock);
1221 clean_req (dev->gadget->ep0, dev->req);
1222 spin_unlock_irq (&dev->lock);
1229 /* can stall some OUT transfers */
1230 } else if (dev->setup_can_stall) {
1231 VDEBUG(dev, "ep0out stall\n");
1232 (void) usb_ep_set_halt (dev->gadget->ep0);
1234 dev->state = STATE_DEV_CONNECTED;
1236 DBG(dev, "bogus ep0out stall!\n");
1239 DBG (dev, "fail %s, state %d\n", __func__, dev->state);
1241 spin_unlock_irq (&dev->lock);
1246 ep0_fasync (int f, struct file *fd, int on)
1248 struct dev_data *dev = fd->private_data;
1249 // caller must F_SETOWN before signal delivery happens
1250 VDEBUG (dev, "%s %s\n", __func__, on ? "on" : "off");
1251 return fasync_helper (f, fd, on, &dev->fasync);
1254 static struct usb_gadget_driver gadgetfs_driver;
1257 dev_release (struct inode *inode, struct file *fd)
1259 struct dev_data *dev = fd->private_data;
1261 /* closing ep0 === shutdown all */
1263 usb_gadget_unregister_driver (&gadgetfs_driver);
1265 /* at this point "good" hardware has disconnected the
1266 * device from USB; the host won't see it any more.
1267 * alternatively, all host requests will time out.
1274 /* other endpoints were all decoupled from this device */
1275 spin_lock_irq(&dev->lock);
1276 dev->state = STATE_DEV_DISABLED;
1277 spin_unlock_irq(&dev->lock);
1282 ep0_poll (struct file *fd, poll_table *wait)
1284 struct dev_data *dev = fd->private_data;
1287 poll_wait(fd, &dev->wait, wait);
1289 spin_lock_irq (&dev->lock);
1291 /* report fd mode change before acting on it */
1292 if (dev->setup_abort) {
1293 dev->setup_abort = 0;
1298 if (dev->state == STATE_DEV_SETUP) {
1299 if (dev->setup_in || dev->setup_can_stall)
1302 if (dev->ev_next != 0)
1306 spin_unlock_irq(&dev->lock);
1310 static long dev_ioctl (struct file *fd, unsigned code, unsigned long value)
1312 struct dev_data *dev = fd->private_data;
1313 struct usb_gadget *gadget = dev->gadget;
1316 if (gadget->ops->ioctl)
1317 ret = gadget->ops->ioctl (gadget, code, value);
1322 /* used after device configuration */
1323 static const struct file_operations ep0_io_operations = {
1324 .owner = THIS_MODULE,
1325 .llseek = no_llseek,
1329 .fasync = ep0_fasync,
1331 .unlocked_ioctl = dev_ioctl,
1332 .release = dev_release,
1335 /*----------------------------------------------------------------------*/
1337 /* The in-kernel gadget driver handles most ep0 issues, in particular
1338 * enumerating the single configuration (as provided from user space).
1340 * Unrecognized ep0 requests may be handled in user space.
1343 static void make_qualifier (struct dev_data *dev)
1345 struct usb_qualifier_descriptor qual;
1346 struct usb_device_descriptor *desc;
1348 qual.bLength = sizeof qual;
1349 qual.bDescriptorType = USB_DT_DEVICE_QUALIFIER;
1350 qual.bcdUSB = cpu_to_le16 (0x0200);
1353 qual.bDeviceClass = desc->bDeviceClass;
1354 qual.bDeviceSubClass = desc->bDeviceSubClass;
1355 qual.bDeviceProtocol = desc->bDeviceProtocol;
1357 /* assumes ep0 uses the same value for both speeds ... */
1358 qual.bMaxPacketSize0 = dev->gadget->ep0->maxpacket;
1360 qual.bNumConfigurations = 1;
1363 memcpy (dev->rbuf, &qual, sizeof qual);
1367 config_buf (struct dev_data *dev, u8 type, unsigned index)
1372 /* only one configuration */
1376 if (gadget_is_dualspeed(dev->gadget)) {
1377 hs = (dev->gadget->speed == USB_SPEED_HIGH);
1378 if (type == USB_DT_OTHER_SPEED_CONFIG)
1382 dev->req->buf = dev->hs_config;
1383 len = le16_to_cpu(dev->hs_config->wTotalLength);
1385 dev->req->buf = dev->config;
1386 len = le16_to_cpu(dev->config->wTotalLength);
1388 ((u8 *)dev->req->buf) [1] = type;
1393 gadgetfs_setup (struct usb_gadget *gadget, const struct usb_ctrlrequest *ctrl)
1395 struct dev_data *dev = get_gadget_data (gadget);
1396 struct usb_request *req = dev->req;
1397 int value = -EOPNOTSUPP;
1398 struct usb_gadgetfs_event *event;
1399 u16 w_value = le16_to_cpu(ctrl->wValue);
1400 u16 w_length = le16_to_cpu(ctrl->wLength);
1402 spin_lock (&dev->lock);
1403 dev->setup_abort = 0;
1404 if (dev->state == STATE_DEV_UNCONNECTED) {
1405 if (gadget_is_dualspeed(gadget)
1406 && gadget->speed == USB_SPEED_HIGH
1407 && dev->hs_config == NULL) {
1408 spin_unlock(&dev->lock);
1409 ERROR (dev, "no high speed config??\n");
1413 dev->state = STATE_DEV_CONNECTED;
1415 INFO (dev, "connected\n");
1416 event = next_event (dev, GADGETFS_CONNECT);
1417 event->u.speed = gadget->speed;
1420 /* host may have given up waiting for response. we can miss control
1421 * requests handled lower down (device/endpoint status and features);
1422 * then ep0_{read,write} will report the wrong status. controller
1423 * driver will have aborted pending i/o.
1425 } else if (dev->state == STATE_DEV_SETUP)
1426 dev->setup_abort = 1;
1428 req->buf = dev->rbuf;
1429 req->context = NULL;
1430 value = -EOPNOTSUPP;
1431 switch (ctrl->bRequest) {
1433 case USB_REQ_GET_DESCRIPTOR:
1434 if (ctrl->bRequestType != USB_DIR_IN)
1436 switch (w_value >> 8) {
1439 value = min (w_length, (u16) sizeof *dev->dev);
1440 dev->dev->bMaxPacketSize0 = dev->gadget->ep0->maxpacket;
1441 req->buf = dev->dev;
1443 case USB_DT_DEVICE_QUALIFIER:
1444 if (!dev->hs_config)
1446 value = min (w_length, (u16)
1447 sizeof (struct usb_qualifier_descriptor));
1448 make_qualifier (dev);
1450 case USB_DT_OTHER_SPEED_CONFIG:
1453 value = config_buf (dev,
1457 value = min (w_length, (u16) value);
1462 default: // all others are errors
1467 /* currently one config, two speeds */
1468 case USB_REQ_SET_CONFIGURATION:
1469 if (ctrl->bRequestType != 0)
1471 if (0 == (u8) w_value) {
1473 dev->current_config = 0;
1474 usb_gadget_vbus_draw(gadget, 8 /* mA */ );
1475 // user mode expected to disable endpoints
1479 if (gadget_is_dualspeed(gadget)
1480 && gadget->speed == USB_SPEED_HIGH) {
1481 config = dev->hs_config->bConfigurationValue;
1482 power = dev->hs_config->bMaxPower;
1484 config = dev->config->bConfigurationValue;
1485 power = dev->config->bMaxPower;
1488 if (config == (u8) w_value) {
1490 dev->current_config = config;
1491 usb_gadget_vbus_draw(gadget, 2 * power);
1495 /* report SET_CONFIGURATION like any other control request,
1496 * except that usermode may not stall this. the next
1497 * request mustn't be allowed start until this finishes:
1498 * endpoints and threads set up, etc.
1500 * NOTE: older PXA hardware (before PXA 255: without UDCCFR)
1501 * has bad/racey automagic that prevents synchronizing here.
1502 * even kernel mode drivers often miss them.
1505 INFO (dev, "configuration #%d\n", dev->current_config);
1506 if (dev->usermode_setup) {
1507 dev->setup_can_stall = 0;
1513 #ifndef CONFIG_USB_GADGET_PXA25X
1514 /* PXA automagically handles this request too */
1515 case USB_REQ_GET_CONFIGURATION:
1516 if (ctrl->bRequestType != 0x80)
1518 *(u8 *)req->buf = dev->current_config;
1519 value = min (w_length, (u16) 1);
1525 VDEBUG (dev, "%s req%02x.%02x v%04x i%04x l%d\n",
1526 dev->usermode_setup ? "delegate" : "fail",
1527 ctrl->bRequestType, ctrl->bRequest,
1528 w_value, le16_to_cpu(ctrl->wIndex), w_length);
1530 /* if there's an ep0 reader, don't stall */
1531 if (dev->usermode_setup) {
1532 dev->setup_can_stall = 1;
1534 dev->setup_in = (ctrl->bRequestType & USB_DIR_IN)
1536 dev->setup_wLength = w_length;
1537 dev->setup_out_ready = 0;
1538 dev->setup_out_error = 0;
1541 /* read DATA stage for OUT right away */
1542 if (unlikely (!dev->setup_in && w_length)) {
1543 value = setup_req (gadget->ep0, dev->req,
1547 value = usb_ep_queue (gadget->ep0, dev->req,
1550 clean_req (gadget->ep0, dev->req);
1554 /* we can't currently stall these */
1555 dev->setup_can_stall = 0;
1558 /* state changes when reader collects event */
1559 event = next_event (dev, GADGETFS_SETUP);
1560 event->u.setup = *ctrl;
1562 spin_unlock (&dev->lock);
1567 /* proceed with data transfer and status phases? */
1568 if (value >= 0 && dev->state != STATE_DEV_SETUP) {
1569 req->length = value;
1570 req->zero = value < w_length;
1571 value = usb_ep_queue (gadget->ep0, req, GFP_ATOMIC);
1573 DBG (dev, "ep_queue --> %d\n", value);
1578 /* device stalls when value < 0 */
1579 spin_unlock (&dev->lock);
1583 static void destroy_ep_files (struct dev_data *dev)
1585 DBG (dev, "%s %d\n", __func__, dev->state);
1587 /* dev->state must prevent interference */
1588 spin_lock_irq (&dev->lock);
1589 while (!list_empty(&dev->epfiles)) {
1591 struct inode *parent;
1592 struct dentry *dentry;
1594 /* break link to FS */
1595 ep = list_first_entry (&dev->epfiles, struct ep_data, epfiles);
1596 list_del_init (&ep->epfiles);
1597 dentry = ep->dentry;
1599 parent = dentry->d_parent->d_inode;
1601 /* break link to controller */
1602 if (ep->state == STATE_EP_ENABLED)
1603 (void) usb_ep_disable (ep->ep);
1604 ep->state = STATE_EP_UNBOUND;
1605 usb_ep_free_request (ep->ep, ep->req);
1607 wake_up (&ep->wait);
1610 spin_unlock_irq (&dev->lock);
1612 /* break link to dcache */
1613 mutex_lock (&parent->i_mutex);
1616 mutex_unlock (&parent->i_mutex);
1618 spin_lock_irq (&dev->lock);
1620 spin_unlock_irq (&dev->lock);
1624 static struct inode *
1625 gadgetfs_create_file (struct super_block *sb, char const *name,
1626 void *data, const struct file_operations *fops,
1627 struct dentry **dentry_p);
1629 static int activate_ep_files (struct dev_data *dev)
1632 struct ep_data *data;
1634 gadget_for_each_ep (ep, dev->gadget) {
1636 data = kzalloc(sizeof(*data), GFP_KERNEL);
1639 data->state = STATE_EP_DISABLED;
1640 mutex_init(&data->lock);
1641 init_waitqueue_head (&data->wait);
1643 strncpy (data->name, ep->name, sizeof (data->name) - 1);
1644 atomic_set (&data->count, 1);
1649 ep->driver_data = data;
1651 data->req = usb_ep_alloc_request (ep, GFP_KERNEL);
1655 data->inode = gadgetfs_create_file (dev->sb, data->name,
1656 data, &ep_config_operations,
1660 list_add_tail (&data->epfiles, &dev->epfiles);
1665 usb_ep_free_request (ep, data->req);
1670 DBG (dev, "%s enomem\n", __func__);
1671 destroy_ep_files (dev);
1676 gadgetfs_unbind (struct usb_gadget *gadget)
1678 struct dev_data *dev = get_gadget_data (gadget);
1680 DBG (dev, "%s\n", __func__);
1682 spin_lock_irq (&dev->lock);
1683 dev->state = STATE_DEV_UNBOUND;
1684 spin_unlock_irq (&dev->lock);
1686 destroy_ep_files (dev);
1687 gadget->ep0->driver_data = NULL;
1688 set_gadget_data (gadget, NULL);
1690 /* we've already been disconnected ... no i/o is active */
1692 usb_ep_free_request (gadget->ep0, dev->req);
1693 DBG (dev, "%s done\n", __func__);
1697 static struct dev_data *the_device;
1699 static int gadgetfs_bind(struct usb_gadget *gadget,
1700 struct usb_gadget_driver *driver)
1702 struct dev_data *dev = the_device;
1706 if (0 != strcmp (CHIP, gadget->name)) {
1707 pr_err("%s expected %s controller not %s\n",
1708 shortname, CHIP, gadget->name);
1712 set_gadget_data (gadget, dev);
1713 dev->gadget = gadget;
1714 gadget->ep0->driver_data = dev;
1716 /* preallocate control response and buffer */
1717 dev->req = usb_ep_alloc_request (gadget->ep0, GFP_KERNEL);
1720 dev->req->context = NULL;
1721 dev->req->complete = epio_complete;
1723 if (activate_ep_files (dev) < 0)
1726 INFO (dev, "bound to %s driver\n", gadget->name);
1727 spin_lock_irq(&dev->lock);
1728 dev->state = STATE_DEV_UNCONNECTED;
1729 spin_unlock_irq(&dev->lock);
1734 gadgetfs_unbind (gadget);
1739 gadgetfs_disconnect (struct usb_gadget *gadget)
1741 struct dev_data *dev = get_gadget_data (gadget);
1742 unsigned long flags;
1744 spin_lock_irqsave (&dev->lock, flags);
1745 if (dev->state == STATE_DEV_UNCONNECTED)
1747 dev->state = STATE_DEV_UNCONNECTED;
1749 INFO (dev, "disconnected\n");
1750 next_event (dev, GADGETFS_DISCONNECT);
1753 spin_unlock_irqrestore (&dev->lock, flags);
1757 gadgetfs_suspend (struct usb_gadget *gadget)
1759 struct dev_data *dev = get_gadget_data (gadget);
1761 INFO (dev, "suspended from state %d\n", dev->state);
1762 spin_lock (&dev->lock);
1763 switch (dev->state) {
1764 case STATE_DEV_SETUP: // VERY odd... host died??
1765 case STATE_DEV_CONNECTED:
1766 case STATE_DEV_UNCONNECTED:
1767 next_event (dev, GADGETFS_SUSPEND);
1773 spin_unlock (&dev->lock);
1776 static struct usb_gadget_driver gadgetfs_driver = {
1777 .function = (char *) driver_desc,
1778 .bind = gadgetfs_bind,
1779 .unbind = gadgetfs_unbind,
1780 .setup = gadgetfs_setup,
1781 .disconnect = gadgetfs_disconnect,
1782 .suspend = gadgetfs_suspend,
1785 .name = (char *) shortname,
1789 /*----------------------------------------------------------------------*/
1791 static void gadgetfs_nop(struct usb_gadget *arg) { }
1793 static int gadgetfs_probe(struct usb_gadget *gadget,
1794 struct usb_gadget_driver *driver)
1796 CHIP = gadget->name;
1800 static struct usb_gadget_driver probe_driver = {
1801 .max_speed = USB_SPEED_HIGH,
1802 .bind = gadgetfs_probe,
1803 .unbind = gadgetfs_nop,
1804 .setup = (void *)gadgetfs_nop,
1805 .disconnect = gadgetfs_nop,
1812 /* DEVICE INITIALIZATION
1814 * fd = open ("/dev/gadget/$CHIP", O_RDWR)
1815 * status = write (fd, descriptors, sizeof descriptors)
1817 * That write establishes the device configuration, so the kernel can
1818 * bind to the controller ... guaranteeing it can handle enumeration
1819 * at all necessary speeds. Descriptor order is:
1821 * . message tag (u32, host order) ... for now, must be zero; it
1822 * would change to support features like multi-config devices
1823 * . full/low speed config ... all wTotalLength bytes (with interface,
1824 * class, altsetting, endpoint, and other descriptors)
1825 * . high speed config ... all descriptors, for high speed operation;
1826 * this one's optional except for high-speed hardware
1827 * . device descriptor
1829 * Endpoints are not yet enabled. Drivers must wait until device
1830 * configuration and interface altsetting changes create
1831 * the need to configure (or unconfigure) them.
1833 * After initialization, the device stays active for as long as that
1834 * $CHIP file is open. Events must then be read from that descriptor,
1835 * such as configuration notifications.
1838 static int is_valid_config (struct usb_config_descriptor *config)
1840 return config->bDescriptorType == USB_DT_CONFIG
1841 && config->bLength == USB_DT_CONFIG_SIZE
1842 && config->bConfigurationValue != 0
1843 && (config->bmAttributes & USB_CONFIG_ATT_ONE) != 0
1844 && (config->bmAttributes & USB_CONFIG_ATT_WAKEUP) == 0;
1845 /* FIXME if gadget->is_otg, _must_ include an otg descriptor */
1846 /* FIXME check lengths: walk to end */
1850 dev_config (struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
1852 struct dev_data *dev = fd->private_data;
1853 ssize_t value = len, length = len;
1858 if (len < (USB_DT_CONFIG_SIZE + USB_DT_DEVICE_SIZE + 4))
1861 /* we might need to change message format someday */
1862 if (copy_from_user (&tag, buf, 4))
1869 kbuf = memdup_user(buf, length);
1871 return PTR_ERR(kbuf);
1873 spin_lock_irq (&dev->lock);
1879 /* full or low speed config */
1880 dev->config = (void *) kbuf;
1881 total = le16_to_cpu(dev->config->wTotalLength);
1882 if (!is_valid_config (dev->config) || total >= length)
1887 /* optional high speed config */
1888 if (kbuf [1] == USB_DT_CONFIG) {
1889 dev->hs_config = (void *) kbuf;
1890 total = le16_to_cpu(dev->hs_config->wTotalLength);
1891 if (!is_valid_config (dev->hs_config) || total >= length)
1897 /* could support multiple configs, using another encoding! */
1899 /* device descriptor (tweaked for paranoia) */
1900 if (length != USB_DT_DEVICE_SIZE)
1902 dev->dev = (void *)kbuf;
1903 if (dev->dev->bLength != USB_DT_DEVICE_SIZE
1904 || dev->dev->bDescriptorType != USB_DT_DEVICE
1905 || dev->dev->bNumConfigurations != 1)
1907 dev->dev->bNumConfigurations = 1;
1908 dev->dev->bcdUSB = cpu_to_le16 (0x0200);
1910 /* triggers gadgetfs_bind(); then we can enumerate. */
1911 spin_unlock_irq (&dev->lock);
1913 gadgetfs_driver.max_speed = USB_SPEED_HIGH;
1915 gadgetfs_driver.max_speed = USB_SPEED_FULL;
1917 value = usb_gadget_probe_driver(&gadgetfs_driver);
1922 /* at this point "good" hardware has for the first time
1923 * let the USB the host see us. alternatively, if users
1924 * unplug/replug that will clear all the error state.
1926 * note: everything running before here was guaranteed
1927 * to choke driver model style diagnostics. from here
1928 * on, they can work ... except in cleanup paths that
1929 * kick in after the ep0 descriptor is closed.
1931 fd->f_op = &ep0_io_operations;
1937 spin_unlock_irq (&dev->lock);
1938 pr_debug ("%s: %s fail %Zd, %p\n", shortname, __func__, value, dev);
1945 dev_open (struct inode *inode, struct file *fd)
1947 struct dev_data *dev = inode->i_private;
1950 spin_lock_irq(&dev->lock);
1951 if (dev->state == STATE_DEV_DISABLED) {
1953 dev->state = STATE_DEV_OPENED;
1954 fd->private_data = dev;
1958 spin_unlock_irq(&dev->lock);
1962 static const struct file_operations dev_init_operations = {
1963 .owner = THIS_MODULE,
1964 .llseek = no_llseek,
1967 .write = dev_config,
1968 .fasync = ep0_fasync,
1969 .unlocked_ioctl = dev_ioctl,
1970 .release = dev_release,
1973 /*----------------------------------------------------------------------*/
1975 /* FILESYSTEM AND SUPERBLOCK OPERATIONS
1977 * Mounting the filesystem creates a controller file, used first for
1978 * device configuration then later for event monitoring.
1982 /* FIXME PAM etc could set this security policy without mount options
1983 * if epfiles inherited ownership and permissons from ep0 ...
1986 static unsigned default_uid;
1987 static unsigned default_gid;
1988 static unsigned default_perm = S_IRUSR | S_IWUSR;
1990 module_param (default_uid, uint, 0644);
1991 module_param (default_gid, uint, 0644);
1992 module_param (default_perm, uint, 0644);
1995 static struct inode *
1996 gadgetfs_make_inode (struct super_block *sb,
1997 void *data, const struct file_operations *fops,
2000 struct inode *inode = new_inode (sb);
2003 inode->i_ino = get_next_ino();
2004 inode->i_mode = mode;
2005 inode->i_uid = make_kuid(&init_user_ns, default_uid);
2006 inode->i_gid = make_kgid(&init_user_ns, default_gid);
2007 inode->i_atime = inode->i_mtime = inode->i_ctime
2009 inode->i_private = data;
2010 inode->i_fop = fops;
2015 /* creates in fs root directory, so non-renamable and non-linkable.
2016 * so inode and dentry are paired, until device reconfig.
2018 static struct inode *
2019 gadgetfs_create_file (struct super_block *sb, char const *name,
2020 void *data, const struct file_operations *fops,
2021 struct dentry **dentry_p)
2023 struct dentry *dentry;
2024 struct inode *inode;
2026 dentry = d_alloc_name(sb->s_root, name);
2030 inode = gadgetfs_make_inode (sb, data, fops,
2031 S_IFREG | (default_perm & S_IRWXUGO));
2036 d_add (dentry, inode);
2041 static const struct super_operations gadget_fs_operations = {
2042 .statfs = simple_statfs,
2043 .drop_inode = generic_delete_inode,
2047 gadgetfs_fill_super (struct super_block *sb, void *opts, int silent)
2049 struct inode *inode;
2050 struct dev_data *dev;
2055 /* fake probe to determine $CHIP */
2056 usb_gadget_probe_driver(&probe_driver);
2061 sb->s_blocksize = PAGE_CACHE_SIZE;
2062 sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
2063 sb->s_magic = GADGETFS_MAGIC;
2064 sb->s_op = &gadget_fs_operations;
2065 sb->s_time_gran = 1;
2068 inode = gadgetfs_make_inode (sb,
2069 NULL, &simple_dir_operations,
2070 S_IFDIR | S_IRUGO | S_IXUGO);
2073 inode->i_op = &simple_dir_inode_operations;
2074 if (!(sb->s_root = d_make_root (inode)))
2077 /* the ep0 file is named after the controller we expect;
2078 * user mode code can use it for sanity checks, like we do.
2085 if (!gadgetfs_create_file (sb, CHIP,
2086 dev, &dev_init_operations,
2092 /* other endpoint files are available after hardware setup,
2093 * from binding to a controller.
2102 /* "mount -t gadgetfs path /dev/gadget" ends up here */
2103 static struct dentry *
2104 gadgetfs_mount (struct file_system_type *t, int flags,
2105 const char *path, void *opts)
2107 return mount_single (t, flags, opts, gadgetfs_fill_super);
2111 gadgetfs_kill_sb (struct super_block *sb)
2113 kill_litter_super (sb);
2115 put_dev (the_device);
2120 /*----------------------------------------------------------------------*/
2122 static struct file_system_type gadgetfs_type = {
2123 .owner = THIS_MODULE,
2125 .mount = gadgetfs_mount,
2126 .kill_sb = gadgetfs_kill_sb,
2129 /*----------------------------------------------------------------------*/
2131 static int __init init (void)
2135 status = register_filesystem (&gadgetfs_type);
2137 pr_info ("%s: %s, version " DRIVER_VERSION "\n",
2138 shortname, driver_desc);
2143 static void __exit cleanup (void)
2145 pr_debug ("unregister %s\n", shortname);
2146 unregister_filesystem (&gadgetfs_type);
2148 module_exit (cleanup);