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;
203 static inline void get_ep (struct ep_data *data)
205 atomic_inc (&data->count);
208 static void put_ep (struct ep_data *data)
210 if (likely (!atomic_dec_and_test (&data->count)))
213 /* needs no more cleanup */
214 BUG_ON (!list_empty (&data->epfiles));
215 BUG_ON (waitqueue_active (&data->wait));
219 /*----------------------------------------------------------------------*/
221 /* most "how to use the hardware" policy choices are in userspace:
222 * mapping endpoint roles (which the driver needs) to the capabilities
223 * which the usb controller has. most of those capabilities are exposed
224 * implicitly, starting with the driver name and then endpoint names.
227 static const char *CHIP;
229 /*----------------------------------------------------------------------*/
231 /* NOTE: don't use dev_printk calls before binding to the gadget
232 * at the end of ep0 configuration, or after unbind.
235 /* too wordy: dev_printk(level , &(d)->gadget->dev , fmt , ## args) */
236 #define xprintk(d,level,fmt,args...) \
237 printk(level "%s: " fmt , shortname , ## args)
240 #define DBG(dev,fmt,args...) \
241 xprintk(dev , KERN_DEBUG , fmt , ## args)
243 #define DBG(dev,fmt,args...) \
250 #define VDEBUG(dev,fmt,args...) \
254 #define ERROR(dev,fmt,args...) \
255 xprintk(dev , KERN_ERR , fmt , ## args)
256 #define INFO(dev,fmt,args...) \
257 xprintk(dev , KERN_INFO , fmt , ## args)
260 /*----------------------------------------------------------------------*/
262 /* SYNCHRONOUS ENDPOINT OPERATIONS (bulk/intr/iso)
264 * After opening, configure non-control endpoints. Then use normal
265 * stream read() and write() requests; and maybe ioctl() to get more
266 * precise FIFO status when recovering from cancellation.
269 static void epio_complete (struct usb_ep *ep, struct usb_request *req)
271 struct ep_data *epdata = ep->driver_data;
276 epdata->status = req->status;
278 epdata->status = req->actual;
279 complete ((struct completion *)req->context);
282 /* tasklock endpoint, returning when it's connected.
283 * still need dev->lock to use epdata->ep.
286 get_ready_ep (unsigned f_flags, struct ep_data *epdata)
290 if (f_flags & O_NONBLOCK) {
291 if (!mutex_trylock(&epdata->lock))
293 if (epdata->state != STATE_EP_ENABLED) {
294 mutex_unlock(&epdata->lock);
302 val = mutex_lock_interruptible(&epdata->lock);
306 switch (epdata->state) {
307 case STATE_EP_ENABLED:
309 // case STATE_EP_DISABLED: /* "can't happen" */
310 // case STATE_EP_READY: /* "can't happen" */
311 default: /* error! */
312 pr_debug ("%s: ep %p not available, state %d\n",
313 shortname, epdata, epdata->state);
315 case STATE_EP_UNBOUND: /* clean disconnect */
317 mutex_unlock(&epdata->lock);
323 ep_io (struct ep_data *epdata, void *buf, unsigned len)
325 DECLARE_COMPLETION_ONSTACK (done);
328 spin_lock_irq (&epdata->dev->lock);
329 if (likely (epdata->ep != NULL)) {
330 struct usb_request *req = epdata->req;
332 req->context = &done;
333 req->complete = epio_complete;
336 value = usb_ep_queue (epdata->ep, req, GFP_ATOMIC);
339 spin_unlock_irq (&epdata->dev->lock);
341 if (likely (value == 0)) {
342 value = wait_event_interruptible (done.wait, done.done);
344 spin_lock_irq (&epdata->dev->lock);
345 if (likely (epdata->ep != NULL)) {
346 DBG (epdata->dev, "%s i/o interrupted\n",
348 usb_ep_dequeue (epdata->ep, epdata->req);
349 spin_unlock_irq (&epdata->dev->lock);
351 wait_event (done.wait, done.done);
352 if (epdata->status == -ECONNRESET)
353 epdata->status = -EINTR;
355 spin_unlock_irq (&epdata->dev->lock);
357 DBG (epdata->dev, "endpoint gone\n");
358 epdata->status = -ENODEV;
361 return epdata->status;
367 /* handle a synchronous OUT bulk/intr/iso transfer */
369 ep_read (struct file *fd, char __user *buf, size_t len, loff_t *ptr)
371 struct ep_data *data = fd->private_data;
375 if ((value = get_ready_ep (fd->f_flags, data)) < 0)
378 /* halt any endpoint by doing a "wrong direction" i/o call */
379 if (usb_endpoint_dir_in(&data->desc)) {
380 if (usb_endpoint_xfer_isoc(&data->desc)) {
381 mutex_unlock(&data->lock);
384 DBG (data->dev, "%s halt\n", data->name);
385 spin_lock_irq (&data->dev->lock);
386 if (likely (data->ep != NULL))
387 usb_ep_set_halt (data->ep);
388 spin_unlock_irq (&data->dev->lock);
389 mutex_unlock(&data->lock);
393 /* FIXME readahead for O_NONBLOCK and poll(); careful with ZLPs */
396 kbuf = kmalloc (len, GFP_KERNEL);
397 if (unlikely (!kbuf))
400 value = ep_io (data, kbuf, len);
401 VDEBUG (data->dev, "%s read %zu OUT, status %d\n",
402 data->name, len, (int) value);
403 if (value >= 0 && copy_to_user (buf, kbuf, value))
407 mutex_unlock(&data->lock);
412 /* handle a synchronous IN bulk/intr/iso transfer */
414 ep_write (struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
416 struct ep_data *data = fd->private_data;
420 if ((value = get_ready_ep (fd->f_flags, data)) < 0)
423 /* halt any endpoint by doing a "wrong direction" i/o call */
424 if (!usb_endpoint_dir_in(&data->desc)) {
425 if (usb_endpoint_xfer_isoc(&data->desc)) {
426 mutex_unlock(&data->lock);
429 DBG (data->dev, "%s halt\n", data->name);
430 spin_lock_irq (&data->dev->lock);
431 if (likely (data->ep != NULL))
432 usb_ep_set_halt (data->ep);
433 spin_unlock_irq (&data->dev->lock);
434 mutex_unlock(&data->lock);
438 /* FIXME writebehind for O_NONBLOCK and poll(), qlen = 1 */
441 kbuf = memdup_user(buf, len);
443 value = PTR_ERR(kbuf);
447 value = ep_io (data, kbuf, len);
448 VDEBUG (data->dev, "%s write %zu IN, status %d\n",
449 data->name, len, (int) value);
451 mutex_unlock(&data->lock);
456 ep_release (struct inode *inode, struct file *fd)
458 struct ep_data *data = fd->private_data;
461 value = mutex_lock_interruptible(&data->lock);
465 /* clean up if this can be reopened */
466 if (data->state != STATE_EP_UNBOUND) {
467 data->state = STATE_EP_DISABLED;
468 data->desc.bDescriptorType = 0;
469 data->hs_desc.bDescriptorType = 0;
470 usb_ep_disable(data->ep);
472 mutex_unlock(&data->lock);
477 static long ep_ioctl(struct file *fd, unsigned code, unsigned long value)
479 struct ep_data *data = fd->private_data;
482 if ((status = get_ready_ep (fd->f_flags, data)) < 0)
485 spin_lock_irq (&data->dev->lock);
486 if (likely (data->ep != NULL)) {
488 case GADGETFS_FIFO_STATUS:
489 status = usb_ep_fifo_status (data->ep);
491 case GADGETFS_FIFO_FLUSH:
492 usb_ep_fifo_flush (data->ep);
494 case GADGETFS_CLEAR_HALT:
495 status = usb_ep_clear_halt (data->ep);
502 spin_unlock_irq (&data->dev->lock);
503 mutex_unlock(&data->lock);
507 /*----------------------------------------------------------------------*/
509 /* ASYNCHRONOUS ENDPOINT I/O OPERATIONS (bulk/intr/iso) */
512 struct usb_request *req;
513 struct ep_data *epdata;
515 struct mm_struct *mm;
516 struct work_struct work;
518 const struct iovec *iv;
519 unsigned long nr_segs;
523 static int ep_aio_cancel(struct kiocb *iocb)
525 struct kiocb_priv *priv = iocb->private;
526 struct ep_data *epdata;
530 epdata = priv->epdata;
531 // spin_lock(&epdata->dev->lock);
532 if (likely(epdata && epdata->ep && priv->req))
533 value = usb_ep_dequeue (epdata->ep, priv->req);
536 // spin_unlock(&epdata->dev->lock);
542 static ssize_t ep_copy_to_user(struct kiocb_priv *priv)
548 /* copy stuff into user buffers */
549 total = priv->actual;
552 for (i=0; i < priv->nr_segs; i++) {
553 ssize_t this = min((ssize_t)(priv->iv[i].iov_len), total);
555 if (copy_to_user(priv->iv[i].iov_base, to_copy, this)) {
571 static void ep_user_copy_worker(struct work_struct *work)
573 struct kiocb_priv *priv = container_of(work, struct kiocb_priv, work);
574 struct mm_struct *mm = priv->mm;
575 struct kiocb *iocb = priv->iocb;
579 ret = ep_copy_to_user(priv);
582 /* completing the iocb can drop the ctx and mm, don't touch mm after */
583 aio_complete(iocb, ret, ret);
589 static void ep_aio_complete(struct usb_ep *ep, struct usb_request *req)
591 struct kiocb *iocb = req->context;
592 struct kiocb_priv *priv = iocb->private;
593 struct ep_data *epdata = priv->epdata;
595 /* lock against disconnect (and ideally, cancel) */
596 spin_lock(&epdata->dev->lock);
600 /* if this was a write or a read returning no data then we
601 * don't need to copy anything to userspace, so we can
602 * complete the aio request immediately.
604 if (priv->iv == NULL || unlikely(req->actual == 0)) {
607 iocb->private = NULL;
608 /* aio_complete() reports bytes-transferred _and_ faults */
609 aio_complete(iocb, req->actual ? req->actual : req->status,
612 /* ep_copy_to_user() won't report both; we hide some faults */
613 if (unlikely(0 != req->status))
614 DBG(epdata->dev, "%s fault %d len %d\n",
615 ep->name, req->status, req->actual);
617 priv->buf = req->buf;
618 priv->actual = req->actual;
619 schedule_work(&priv->work);
621 spin_unlock(&epdata->dev->lock);
623 usb_ep_free_request(ep, req);
632 struct ep_data *epdata,
633 const struct iovec *iv,
634 unsigned long nr_segs
637 struct kiocb_priv *priv;
638 struct usb_request *req;
641 priv = kmalloc(sizeof *priv, GFP_KERNEL);
648 iocb->private = priv;
651 priv->nr_segs = nr_segs;
652 INIT_WORK(&priv->work, ep_user_copy_worker);
654 value = get_ready_ep(iocb->ki_filp->f_flags, epdata);
655 if (unlikely(value < 0)) {
660 kiocb_set_cancel_fn(iocb, ep_aio_cancel);
662 priv->epdata = epdata;
664 priv->mm = current->mm; /* mm teardown waits for iocbs in exit_aio() */
666 /* each kiocb is coupled to one usb_request, but we can't
667 * allocate or submit those if the host disconnected.
669 spin_lock_irq(&epdata->dev->lock);
670 if (likely(epdata->ep)) {
671 req = usb_ep_alloc_request(epdata->ep, GFP_ATOMIC);
676 req->complete = ep_aio_complete;
678 value = usb_ep_queue(epdata->ep, req, GFP_ATOMIC);
679 if (unlikely(0 != value))
680 usb_ep_free_request(epdata->ep, req);
685 spin_unlock_irq(&epdata->dev->lock);
687 mutex_unlock(&epdata->lock);
689 if (unlikely(value)) {
693 value = -EIOCBQUEUED;
698 ep_aio_read(struct kiocb *iocb, const struct iovec *iov,
699 unsigned long nr_segs, loff_t o)
701 struct ep_data *epdata = iocb->ki_filp->private_data;
704 if (unlikely(usb_endpoint_dir_in(&epdata->desc)))
707 buf = kmalloc(iocb->ki_nbytes, GFP_KERNEL);
711 return ep_aio_rwtail(iocb, buf, iocb->ki_nbytes, epdata, iov, nr_segs);
715 ep_aio_write(struct kiocb *iocb, const struct iovec *iov,
716 unsigned long nr_segs, loff_t o)
718 struct ep_data *epdata = iocb->ki_filp->private_data;
723 if (unlikely(!usb_endpoint_dir_in(&epdata->desc)))
726 buf = kmalloc(iocb->ki_nbytes, GFP_KERNEL);
730 for (i=0; i < nr_segs; i++) {
731 if (unlikely(copy_from_user(&buf[len], iov[i].iov_base,
732 iov[i].iov_len) != 0)) {
736 len += iov[i].iov_len;
738 return ep_aio_rwtail(iocb, buf, len, epdata, NULL, 0);
741 /*----------------------------------------------------------------------*/
743 /* used after endpoint configuration */
744 static const struct file_operations ep_io_operations = {
745 .owner = THIS_MODULE,
750 .unlocked_ioctl = ep_ioctl,
751 .release = ep_release,
753 .aio_read = ep_aio_read,
754 .aio_write = ep_aio_write,
757 /* ENDPOINT INITIALIZATION
759 * fd = open ("/dev/gadget/$ENDPOINT", O_RDWR)
760 * status = write (fd, descriptors, sizeof descriptors)
762 * That write establishes the endpoint configuration, configuring
763 * the controller to process bulk, interrupt, or isochronous transfers
764 * at the right maxpacket size, and so on.
766 * The descriptors are message type 1, identified by a host order u32
767 * at the beginning of what's written. Descriptor order is: full/low
768 * speed descriptor, then optional high speed descriptor.
771 ep_config (struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
773 struct ep_data *data = fd->private_data;
776 int value, length = len;
778 value = mutex_lock_interruptible(&data->lock);
782 if (data->state != STATE_EP_READY) {
788 if (len < USB_DT_ENDPOINT_SIZE + 4)
791 /* we might need to change message format someday */
792 if (copy_from_user (&tag, buf, 4)) {
796 DBG(data->dev, "config %s, bad tag %d\n", data->name, tag);
802 /* NOTE: audio endpoint extensions not accepted here;
803 * just don't include the extra bytes.
806 /* full/low speed descriptor, then high speed */
807 if (copy_from_user (&data->desc, buf, USB_DT_ENDPOINT_SIZE)) {
810 if (data->desc.bLength != USB_DT_ENDPOINT_SIZE
811 || data->desc.bDescriptorType != USB_DT_ENDPOINT)
813 if (len != USB_DT_ENDPOINT_SIZE) {
814 if (len != 2 * USB_DT_ENDPOINT_SIZE)
816 if (copy_from_user (&data->hs_desc, buf + USB_DT_ENDPOINT_SIZE,
817 USB_DT_ENDPOINT_SIZE)) {
820 if (data->hs_desc.bLength != USB_DT_ENDPOINT_SIZE
821 || data->hs_desc.bDescriptorType
822 != USB_DT_ENDPOINT) {
823 DBG(data->dev, "config %s, bad hs length or type\n",
829 spin_lock_irq (&data->dev->lock);
830 if (data->dev->state == STATE_DEV_UNBOUND) {
833 } else if ((ep = data->ep) == NULL) {
837 switch (data->dev->gadget->speed) {
840 ep->desc = &data->desc;
841 value = usb_ep_enable(ep);
843 data->state = STATE_EP_ENABLED;
846 /* fails if caller didn't provide that descriptor... */
847 ep->desc = &data->hs_desc;
848 value = usb_ep_enable(ep);
850 data->state = STATE_EP_ENABLED;
853 DBG(data->dev, "unconnected, %s init abandoned\n",
858 fd->f_op = &ep_io_operations;
862 spin_unlock_irq (&data->dev->lock);
865 data->desc.bDescriptorType = 0;
866 data->hs_desc.bDescriptorType = 0;
868 mutex_unlock(&data->lock);
879 ep_open (struct inode *inode, struct file *fd)
881 struct ep_data *data = inode->i_private;
884 if (mutex_lock_interruptible(&data->lock) != 0)
886 spin_lock_irq (&data->dev->lock);
887 if (data->dev->state == STATE_DEV_UNBOUND)
889 else if (data->state == STATE_EP_DISABLED) {
891 data->state = STATE_EP_READY;
893 fd->private_data = data;
894 VDEBUG (data->dev, "%s ready\n", data->name);
896 DBG (data->dev, "%s state %d\n",
897 data->name, data->state);
898 spin_unlock_irq (&data->dev->lock);
899 mutex_unlock(&data->lock);
903 /* used before endpoint configuration */
904 static const struct file_operations ep_config_operations = {
909 .release = ep_release,
912 /*----------------------------------------------------------------------*/
914 /* EP0 IMPLEMENTATION can be partly in userspace.
916 * Drivers that use this facility receive various events, including
917 * control requests the kernel doesn't handle. Drivers that don't
918 * use this facility may be too simple-minded for real applications.
921 static inline void ep0_readable (struct dev_data *dev)
923 wake_up (&dev->wait);
924 kill_fasync (&dev->fasync, SIGIO, POLL_IN);
927 static void clean_req (struct usb_ep *ep, struct usb_request *req)
929 struct dev_data *dev = ep->driver_data;
931 if (req->buf != dev->rbuf) {
933 req->buf = dev->rbuf;
935 req->complete = epio_complete;
936 dev->setup_out_ready = 0;
939 static void ep0_complete (struct usb_ep *ep, struct usb_request *req)
941 struct dev_data *dev = ep->driver_data;
945 /* for control OUT, data must still get to userspace */
946 spin_lock_irqsave(&dev->lock, flags);
947 if (!dev->setup_in) {
948 dev->setup_out_error = (req->status != 0);
949 if (!dev->setup_out_error)
951 dev->setup_out_ready = 1;
955 /* clean up as appropriate */
956 if (free && req->buf != &dev->rbuf)
958 req->complete = epio_complete;
959 spin_unlock_irqrestore(&dev->lock, flags);
962 static int setup_req (struct usb_ep *ep, struct usb_request *req, u16 len)
964 struct dev_data *dev = ep->driver_data;
966 if (dev->setup_out_ready) {
967 DBG (dev, "ep0 request busy!\n");
970 if (len > sizeof (dev->rbuf))
971 req->buf = kmalloc(len, GFP_ATOMIC);
972 if (req->buf == NULL) {
973 req->buf = dev->rbuf;
976 req->complete = ep0_complete;
983 ep0_read (struct file *fd, char __user *buf, size_t len, loff_t *ptr)
985 struct dev_data *dev = fd->private_data;
987 enum ep0_state state;
989 spin_lock_irq (&dev->lock);
991 /* report fd mode change before acting on it */
992 if (dev->setup_abort) {
993 dev->setup_abort = 0;
998 /* control DATA stage */
999 if ((state = dev->state) == STATE_DEV_SETUP) {
1001 if (dev->setup_in) { /* stall IN */
1002 VDEBUG(dev, "ep0in stall\n");
1003 (void) usb_ep_set_halt (dev->gadget->ep0);
1005 dev->state = STATE_DEV_CONNECTED;
1007 } else if (len == 0) { /* ack SET_CONFIGURATION etc */
1008 struct usb_ep *ep = dev->gadget->ep0;
1009 struct usb_request *req = dev->req;
1011 if ((retval = setup_req (ep, req, 0)) == 0)
1012 retval = usb_ep_queue (ep, req, GFP_ATOMIC);
1013 dev->state = STATE_DEV_CONNECTED;
1015 /* assume that was SET_CONFIGURATION */
1016 if (dev->current_config) {
1019 if (gadget_is_dualspeed(dev->gadget)
1020 && (dev->gadget->speed
1022 power = dev->hs_config->bMaxPower;
1024 power = dev->config->bMaxPower;
1025 usb_gadget_vbus_draw(dev->gadget, 2 * power);
1028 } else { /* collect OUT data */
1029 if ((fd->f_flags & O_NONBLOCK) != 0
1030 && !dev->setup_out_ready) {
1034 spin_unlock_irq (&dev->lock);
1035 retval = wait_event_interruptible (dev->wait,
1036 dev->setup_out_ready != 0);
1038 /* FIXME state could change from under us */
1039 spin_lock_irq (&dev->lock);
1043 if (dev->state != STATE_DEV_SETUP) {
1044 retval = -ECANCELED;
1047 dev->state = STATE_DEV_CONNECTED;
1049 if (dev->setup_out_error)
1052 len = min (len, (size_t)dev->req->actual);
1053 // FIXME don't call this with the spinlock held ...
1054 if (copy_to_user (buf, dev->req->buf, len))
1058 clean_req (dev->gadget->ep0, dev->req);
1059 /* NOTE userspace can't yet choose to stall */
1065 /* else normal: return event data */
1066 if (len < sizeof dev->event [0]) {
1070 len -= len % sizeof (struct usb_gadgetfs_event);
1071 dev->usermode_setup = 1;
1074 /* return queued events right away */
1075 if (dev->ev_next != 0) {
1078 n = len / sizeof (struct usb_gadgetfs_event);
1079 if (dev->ev_next < n)
1082 /* ep0 i/o has special semantics during STATE_DEV_SETUP */
1083 for (i = 0; i < n; i++) {
1084 if (dev->event [i].type == GADGETFS_SETUP) {
1085 dev->state = STATE_DEV_SETUP;
1090 spin_unlock_irq (&dev->lock);
1091 len = n * sizeof (struct usb_gadgetfs_event);
1092 if (copy_to_user (buf, &dev->event, len))
1097 /* NOTE this doesn't guard against broken drivers;
1098 * concurrent ep0 readers may lose events.
1100 spin_lock_irq (&dev->lock);
1101 if (dev->ev_next > n) {
1102 memmove(&dev->event[0], &dev->event[n],
1103 sizeof (struct usb_gadgetfs_event)
1104 * (dev->ev_next - n));
1107 spin_unlock_irq (&dev->lock);
1111 if (fd->f_flags & O_NONBLOCK) {
1118 DBG (dev, "fail %s, state %d\n", __func__, state);
1121 case STATE_DEV_UNCONNECTED:
1122 case STATE_DEV_CONNECTED:
1123 spin_unlock_irq (&dev->lock);
1124 DBG (dev, "%s wait\n", __func__);
1126 /* wait for events */
1127 retval = wait_event_interruptible (dev->wait,
1131 spin_lock_irq (&dev->lock);
1136 spin_unlock_irq (&dev->lock);
1140 static struct usb_gadgetfs_event *
1141 next_event (struct dev_data *dev, enum usb_gadgetfs_event_type type)
1143 struct usb_gadgetfs_event *event;
1147 /* these events purge the queue */
1148 case GADGETFS_DISCONNECT:
1149 if (dev->state == STATE_DEV_SETUP)
1150 dev->setup_abort = 1;
1152 case GADGETFS_CONNECT:
1155 case GADGETFS_SETUP: /* previous request timed out */
1156 case GADGETFS_SUSPEND: /* same effect */
1157 /* these events can't be repeated */
1158 for (i = 0; i != dev->ev_next; i++) {
1159 if (dev->event [i].type != type)
1161 DBG(dev, "discard old event[%d] %d\n", i, type);
1163 if (i == dev->ev_next)
1165 /* indices start at zero, for simplicity */
1166 memmove (&dev->event [i], &dev->event [i + 1],
1167 sizeof (struct usb_gadgetfs_event)
1168 * (dev->ev_next - i));
1174 VDEBUG(dev, "event[%d] = %d\n", dev->ev_next, type);
1175 event = &dev->event [dev->ev_next++];
1176 BUG_ON (dev->ev_next > N_EVENT);
1177 memset (event, 0, sizeof *event);
1183 ep0_write (struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
1185 struct dev_data *dev = fd->private_data;
1186 ssize_t retval = -ESRCH;
1188 spin_lock_irq (&dev->lock);
1190 /* report fd mode change before acting on it */
1191 if (dev->setup_abort) {
1192 dev->setup_abort = 0;
1195 /* data and/or status stage for control request */
1196 } else if (dev->state == STATE_DEV_SETUP) {
1198 /* IN DATA+STATUS caller makes len <= wLength */
1199 if (dev->setup_in) {
1200 retval = setup_req (dev->gadget->ep0, dev->req, len);
1202 dev->state = STATE_DEV_CONNECTED;
1203 spin_unlock_irq (&dev->lock);
1204 if (copy_from_user (dev->req->buf, buf, len))
1207 if (len < dev->setup_wLength)
1209 retval = usb_ep_queue (
1210 dev->gadget->ep0, dev->req,
1214 spin_lock_irq (&dev->lock);
1215 clean_req (dev->gadget->ep0, dev->req);
1216 spin_unlock_irq (&dev->lock);
1223 /* can stall some OUT transfers */
1224 } else if (dev->setup_can_stall) {
1225 VDEBUG(dev, "ep0out stall\n");
1226 (void) usb_ep_set_halt (dev->gadget->ep0);
1228 dev->state = STATE_DEV_CONNECTED;
1230 DBG(dev, "bogus ep0out stall!\n");
1233 DBG (dev, "fail %s, state %d\n", __func__, dev->state);
1235 spin_unlock_irq (&dev->lock);
1240 ep0_fasync (int f, struct file *fd, int on)
1242 struct dev_data *dev = fd->private_data;
1243 // caller must F_SETOWN before signal delivery happens
1244 VDEBUG (dev, "%s %s\n", __func__, on ? "on" : "off");
1245 return fasync_helper (f, fd, on, &dev->fasync);
1248 static struct usb_gadget_driver gadgetfs_driver;
1251 dev_release (struct inode *inode, struct file *fd)
1253 struct dev_data *dev = fd->private_data;
1255 /* closing ep0 === shutdown all */
1257 usb_gadget_unregister_driver (&gadgetfs_driver);
1259 /* at this point "good" hardware has disconnected the
1260 * device from USB; the host won't see it any more.
1261 * alternatively, all host requests will time out.
1267 /* other endpoints were all decoupled from this device */
1268 spin_lock_irq(&dev->lock);
1269 dev->state = STATE_DEV_DISABLED;
1270 spin_unlock_irq(&dev->lock);
1277 ep0_poll (struct file *fd, poll_table *wait)
1279 struct dev_data *dev = fd->private_data;
1282 poll_wait(fd, &dev->wait, wait);
1284 spin_lock_irq (&dev->lock);
1286 /* report fd mode change before acting on it */
1287 if (dev->setup_abort) {
1288 dev->setup_abort = 0;
1293 if (dev->state == STATE_DEV_SETUP) {
1294 if (dev->setup_in || dev->setup_can_stall)
1297 if (dev->ev_next != 0)
1301 spin_unlock_irq(&dev->lock);
1305 static long dev_ioctl (struct file *fd, unsigned code, unsigned long value)
1307 struct dev_data *dev = fd->private_data;
1308 struct usb_gadget *gadget = dev->gadget;
1311 if (gadget->ops->ioctl)
1312 ret = gadget->ops->ioctl (gadget, code, value);
1317 /* used after device configuration */
1318 static const struct file_operations ep0_io_operations = {
1319 .owner = THIS_MODULE,
1320 .llseek = no_llseek,
1324 .fasync = ep0_fasync,
1326 .unlocked_ioctl = dev_ioctl,
1327 .release = dev_release,
1330 /*----------------------------------------------------------------------*/
1332 /* The in-kernel gadget driver handles most ep0 issues, in particular
1333 * enumerating the single configuration (as provided from user space).
1335 * Unrecognized ep0 requests may be handled in user space.
1338 static void make_qualifier (struct dev_data *dev)
1340 struct usb_qualifier_descriptor qual;
1341 struct usb_device_descriptor *desc;
1343 qual.bLength = sizeof qual;
1344 qual.bDescriptorType = USB_DT_DEVICE_QUALIFIER;
1345 qual.bcdUSB = cpu_to_le16 (0x0200);
1348 qual.bDeviceClass = desc->bDeviceClass;
1349 qual.bDeviceSubClass = desc->bDeviceSubClass;
1350 qual.bDeviceProtocol = desc->bDeviceProtocol;
1352 /* assumes ep0 uses the same value for both speeds ... */
1353 qual.bMaxPacketSize0 = dev->gadget->ep0->maxpacket;
1355 qual.bNumConfigurations = 1;
1358 memcpy (dev->rbuf, &qual, sizeof qual);
1362 config_buf (struct dev_data *dev, u8 type, unsigned index)
1367 /* only one configuration */
1371 if (gadget_is_dualspeed(dev->gadget)) {
1372 hs = (dev->gadget->speed == USB_SPEED_HIGH);
1373 if (type == USB_DT_OTHER_SPEED_CONFIG)
1377 dev->req->buf = dev->hs_config;
1378 len = le16_to_cpu(dev->hs_config->wTotalLength);
1380 dev->req->buf = dev->config;
1381 len = le16_to_cpu(dev->config->wTotalLength);
1383 ((u8 *)dev->req->buf) [1] = type;
1388 gadgetfs_setup (struct usb_gadget *gadget, const struct usb_ctrlrequest *ctrl)
1390 struct dev_data *dev = get_gadget_data (gadget);
1391 struct usb_request *req = dev->req;
1392 int value = -EOPNOTSUPP;
1393 struct usb_gadgetfs_event *event;
1394 u16 w_value = le16_to_cpu(ctrl->wValue);
1395 u16 w_length = le16_to_cpu(ctrl->wLength);
1397 spin_lock (&dev->lock);
1398 dev->setup_abort = 0;
1399 if (dev->state == STATE_DEV_UNCONNECTED) {
1400 if (gadget_is_dualspeed(gadget)
1401 && gadget->speed == USB_SPEED_HIGH
1402 && dev->hs_config == NULL) {
1403 spin_unlock(&dev->lock);
1404 ERROR (dev, "no high speed config??\n");
1408 dev->state = STATE_DEV_CONNECTED;
1410 INFO (dev, "connected\n");
1411 event = next_event (dev, GADGETFS_CONNECT);
1412 event->u.speed = gadget->speed;
1415 /* host may have given up waiting for response. we can miss control
1416 * requests handled lower down (device/endpoint status and features);
1417 * then ep0_{read,write} will report the wrong status. controller
1418 * driver will have aborted pending i/o.
1420 } else if (dev->state == STATE_DEV_SETUP)
1421 dev->setup_abort = 1;
1423 req->buf = dev->rbuf;
1424 req->context = NULL;
1425 value = -EOPNOTSUPP;
1426 switch (ctrl->bRequest) {
1428 case USB_REQ_GET_DESCRIPTOR:
1429 if (ctrl->bRequestType != USB_DIR_IN)
1431 switch (w_value >> 8) {
1434 value = min (w_length, (u16) sizeof *dev->dev);
1435 dev->dev->bMaxPacketSize0 = dev->gadget->ep0->maxpacket;
1436 req->buf = dev->dev;
1438 case USB_DT_DEVICE_QUALIFIER:
1439 if (!dev->hs_config)
1441 value = min (w_length, (u16)
1442 sizeof (struct usb_qualifier_descriptor));
1443 make_qualifier (dev);
1445 case USB_DT_OTHER_SPEED_CONFIG:
1448 value = config_buf (dev,
1452 value = min (w_length, (u16) value);
1457 default: // all others are errors
1462 /* currently one config, two speeds */
1463 case USB_REQ_SET_CONFIGURATION:
1464 if (ctrl->bRequestType != 0)
1466 if (0 == (u8) w_value) {
1468 dev->current_config = 0;
1469 usb_gadget_vbus_draw(gadget, 8 /* mA */ );
1470 // user mode expected to disable endpoints
1474 if (gadget_is_dualspeed(gadget)
1475 && gadget->speed == USB_SPEED_HIGH) {
1476 config = dev->hs_config->bConfigurationValue;
1477 power = dev->hs_config->bMaxPower;
1479 config = dev->config->bConfigurationValue;
1480 power = dev->config->bMaxPower;
1483 if (config == (u8) w_value) {
1485 dev->current_config = config;
1486 usb_gadget_vbus_draw(gadget, 2 * power);
1490 /* report SET_CONFIGURATION like any other control request,
1491 * except that usermode may not stall this. the next
1492 * request mustn't be allowed start until this finishes:
1493 * endpoints and threads set up, etc.
1495 * NOTE: older PXA hardware (before PXA 255: without UDCCFR)
1496 * has bad/racey automagic that prevents synchronizing here.
1497 * even kernel mode drivers often miss them.
1500 INFO (dev, "configuration #%d\n", dev->current_config);
1501 usb_gadget_set_state(gadget, USB_STATE_CONFIGURED);
1502 if (dev->usermode_setup) {
1503 dev->setup_can_stall = 0;
1509 #ifndef CONFIG_USB_PXA25X
1510 /* PXA automagically handles this request too */
1511 case USB_REQ_GET_CONFIGURATION:
1512 if (ctrl->bRequestType != 0x80)
1514 *(u8 *)req->buf = dev->current_config;
1515 value = min (w_length, (u16) 1);
1521 VDEBUG (dev, "%s req%02x.%02x v%04x i%04x l%d\n",
1522 dev->usermode_setup ? "delegate" : "fail",
1523 ctrl->bRequestType, ctrl->bRequest,
1524 w_value, le16_to_cpu(ctrl->wIndex), w_length);
1526 /* if there's an ep0 reader, don't stall */
1527 if (dev->usermode_setup) {
1528 dev->setup_can_stall = 1;
1530 dev->setup_in = (ctrl->bRequestType & USB_DIR_IN)
1532 dev->setup_wLength = w_length;
1533 dev->setup_out_ready = 0;
1534 dev->setup_out_error = 0;
1537 /* read DATA stage for OUT right away */
1538 if (unlikely (!dev->setup_in && w_length)) {
1539 value = setup_req (gadget->ep0, dev->req,
1543 value = usb_ep_queue (gadget->ep0, dev->req,
1546 clean_req (gadget->ep0, dev->req);
1550 /* we can't currently stall these */
1551 dev->setup_can_stall = 0;
1554 /* state changes when reader collects event */
1555 event = next_event (dev, GADGETFS_SETUP);
1556 event->u.setup = *ctrl;
1558 spin_unlock (&dev->lock);
1563 /* proceed with data transfer and status phases? */
1564 if (value >= 0 && dev->state != STATE_DEV_SETUP) {
1565 req->length = value;
1566 req->zero = value < w_length;
1567 value = usb_ep_queue (gadget->ep0, req, GFP_ATOMIC);
1569 DBG (dev, "ep_queue --> %d\n", value);
1574 /* device stalls when value < 0 */
1575 spin_unlock (&dev->lock);
1579 static void destroy_ep_files (struct dev_data *dev)
1581 DBG (dev, "%s %d\n", __func__, dev->state);
1583 /* dev->state must prevent interference */
1584 spin_lock_irq (&dev->lock);
1585 while (!list_empty(&dev->epfiles)) {
1587 struct inode *parent;
1588 struct dentry *dentry;
1590 /* break link to FS */
1591 ep = list_first_entry (&dev->epfiles, struct ep_data, epfiles);
1592 list_del_init (&ep->epfiles);
1593 dentry = ep->dentry;
1595 parent = dentry->d_parent->d_inode;
1597 /* break link to controller */
1598 if (ep->state == STATE_EP_ENABLED)
1599 (void) usb_ep_disable (ep->ep);
1600 ep->state = STATE_EP_UNBOUND;
1601 usb_ep_free_request (ep->ep, ep->req);
1603 wake_up (&ep->wait);
1606 spin_unlock_irq (&dev->lock);
1608 /* break link to dcache */
1609 mutex_lock (&parent->i_mutex);
1612 mutex_unlock (&parent->i_mutex);
1614 spin_lock_irq (&dev->lock);
1616 spin_unlock_irq (&dev->lock);
1620 static struct dentry *
1621 gadgetfs_create_file (struct super_block *sb, char const *name,
1622 void *data, const struct file_operations *fops);
1624 static int activate_ep_files (struct dev_data *dev)
1627 struct ep_data *data;
1629 gadget_for_each_ep (ep, dev->gadget) {
1631 data = kzalloc(sizeof(*data), GFP_KERNEL);
1634 data->state = STATE_EP_DISABLED;
1635 mutex_init(&data->lock);
1636 init_waitqueue_head (&data->wait);
1638 strncpy (data->name, ep->name, sizeof (data->name) - 1);
1639 atomic_set (&data->count, 1);
1644 ep->driver_data = data;
1646 data->req = usb_ep_alloc_request (ep, GFP_KERNEL);
1650 data->dentry = gadgetfs_create_file (dev->sb, data->name,
1651 data, &ep_config_operations);
1654 list_add_tail (&data->epfiles, &dev->epfiles);
1659 usb_ep_free_request (ep, data->req);
1664 DBG (dev, "%s enomem\n", __func__);
1665 destroy_ep_files (dev);
1670 gadgetfs_unbind (struct usb_gadget *gadget)
1672 struct dev_data *dev = get_gadget_data (gadget);
1674 DBG (dev, "%s\n", __func__);
1676 spin_lock_irq (&dev->lock);
1677 dev->state = STATE_DEV_UNBOUND;
1678 spin_unlock_irq (&dev->lock);
1680 destroy_ep_files (dev);
1681 gadget->ep0->driver_data = NULL;
1682 set_gadget_data (gadget, NULL);
1684 /* we've already been disconnected ... no i/o is active */
1686 usb_ep_free_request (gadget->ep0, dev->req);
1687 DBG (dev, "%s done\n", __func__);
1691 static struct dev_data *the_device;
1693 static int gadgetfs_bind(struct usb_gadget *gadget,
1694 struct usb_gadget_driver *driver)
1696 struct dev_data *dev = the_device;
1700 if (0 != strcmp (CHIP, gadget->name)) {
1701 pr_err("%s expected %s controller not %s\n",
1702 shortname, CHIP, gadget->name);
1706 set_gadget_data (gadget, dev);
1707 dev->gadget = gadget;
1708 gadget->ep0->driver_data = dev;
1710 /* preallocate control response and buffer */
1711 dev->req = usb_ep_alloc_request (gadget->ep0, GFP_KERNEL);
1714 dev->req->context = NULL;
1715 dev->req->complete = epio_complete;
1717 if (activate_ep_files (dev) < 0)
1720 INFO (dev, "bound to %s driver\n", gadget->name);
1721 spin_lock_irq(&dev->lock);
1722 dev->state = STATE_DEV_UNCONNECTED;
1723 spin_unlock_irq(&dev->lock);
1728 gadgetfs_unbind (gadget);
1733 gadgetfs_disconnect (struct usb_gadget *gadget)
1735 struct dev_data *dev = get_gadget_data (gadget);
1736 unsigned long flags;
1738 spin_lock_irqsave (&dev->lock, flags);
1739 if (dev->state == STATE_DEV_UNCONNECTED)
1741 dev->state = STATE_DEV_UNCONNECTED;
1743 INFO (dev, "disconnected\n");
1744 next_event (dev, GADGETFS_DISCONNECT);
1747 spin_unlock_irqrestore (&dev->lock, flags);
1751 gadgetfs_suspend (struct usb_gadget *gadget)
1753 struct dev_data *dev = get_gadget_data (gadget);
1755 INFO (dev, "suspended from state %d\n", dev->state);
1756 spin_lock (&dev->lock);
1757 switch (dev->state) {
1758 case STATE_DEV_SETUP: // VERY odd... host died??
1759 case STATE_DEV_CONNECTED:
1760 case STATE_DEV_UNCONNECTED:
1761 next_event (dev, GADGETFS_SUSPEND);
1767 spin_unlock (&dev->lock);
1770 static struct usb_gadget_driver gadgetfs_driver = {
1771 .function = (char *) driver_desc,
1772 .bind = gadgetfs_bind,
1773 .unbind = gadgetfs_unbind,
1774 .setup = gadgetfs_setup,
1775 .reset = gadgetfs_disconnect,
1776 .disconnect = gadgetfs_disconnect,
1777 .suspend = gadgetfs_suspend,
1780 .name = (char *) shortname,
1784 /*----------------------------------------------------------------------*/
1786 static void gadgetfs_nop(struct usb_gadget *arg) { }
1788 static int gadgetfs_probe(struct usb_gadget *gadget,
1789 struct usb_gadget_driver *driver)
1791 CHIP = gadget->name;
1795 static struct usb_gadget_driver probe_driver = {
1796 .max_speed = USB_SPEED_HIGH,
1797 .bind = gadgetfs_probe,
1798 .unbind = gadgetfs_nop,
1799 .setup = (void *)gadgetfs_nop,
1800 .disconnect = gadgetfs_nop,
1807 /* DEVICE INITIALIZATION
1809 * fd = open ("/dev/gadget/$CHIP", O_RDWR)
1810 * status = write (fd, descriptors, sizeof descriptors)
1812 * That write establishes the device configuration, so the kernel can
1813 * bind to the controller ... guaranteeing it can handle enumeration
1814 * at all necessary speeds. Descriptor order is:
1816 * . message tag (u32, host order) ... for now, must be zero; it
1817 * would change to support features like multi-config devices
1818 * . full/low speed config ... all wTotalLength bytes (with interface,
1819 * class, altsetting, endpoint, and other descriptors)
1820 * . high speed config ... all descriptors, for high speed operation;
1821 * this one's optional except for high-speed hardware
1822 * . device descriptor
1824 * Endpoints are not yet enabled. Drivers must wait until device
1825 * configuration and interface altsetting changes create
1826 * the need to configure (or unconfigure) them.
1828 * After initialization, the device stays active for as long as that
1829 * $CHIP file is open. Events must then be read from that descriptor,
1830 * such as configuration notifications.
1833 static int is_valid_config (struct usb_config_descriptor *config)
1835 return config->bDescriptorType == USB_DT_CONFIG
1836 && config->bLength == USB_DT_CONFIG_SIZE
1837 && config->bConfigurationValue != 0
1838 && (config->bmAttributes & USB_CONFIG_ATT_ONE) != 0
1839 && (config->bmAttributes & USB_CONFIG_ATT_WAKEUP) == 0;
1840 /* FIXME if gadget->is_otg, _must_ include an otg descriptor */
1841 /* FIXME check lengths: walk to end */
1845 dev_config (struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
1847 struct dev_data *dev = fd->private_data;
1848 ssize_t value = len, length = len;
1853 if (len < (USB_DT_CONFIG_SIZE + USB_DT_DEVICE_SIZE + 4))
1856 /* we might need to change message format someday */
1857 if (copy_from_user (&tag, buf, 4))
1864 kbuf = memdup_user(buf, length);
1866 return PTR_ERR(kbuf);
1868 spin_lock_irq (&dev->lock);
1874 /* full or low speed config */
1875 dev->config = (void *) kbuf;
1876 total = le16_to_cpu(dev->config->wTotalLength);
1877 if (!is_valid_config (dev->config) || total >= length)
1882 /* optional high speed config */
1883 if (kbuf [1] == USB_DT_CONFIG) {
1884 dev->hs_config = (void *) kbuf;
1885 total = le16_to_cpu(dev->hs_config->wTotalLength);
1886 if (!is_valid_config (dev->hs_config) || total >= length)
1892 /* could support multiple configs, using another encoding! */
1894 /* device descriptor (tweaked for paranoia) */
1895 if (length != USB_DT_DEVICE_SIZE)
1897 dev->dev = (void *)kbuf;
1898 if (dev->dev->bLength != USB_DT_DEVICE_SIZE
1899 || dev->dev->bDescriptorType != USB_DT_DEVICE
1900 || dev->dev->bNumConfigurations != 1)
1902 dev->dev->bNumConfigurations = 1;
1903 dev->dev->bcdUSB = cpu_to_le16 (0x0200);
1905 /* triggers gadgetfs_bind(); then we can enumerate. */
1906 spin_unlock_irq (&dev->lock);
1908 gadgetfs_driver.max_speed = USB_SPEED_HIGH;
1910 gadgetfs_driver.max_speed = USB_SPEED_FULL;
1912 value = usb_gadget_probe_driver(&gadgetfs_driver);
1917 /* at this point "good" hardware has for the first time
1918 * let the USB the host see us. alternatively, if users
1919 * unplug/replug that will clear all the error state.
1921 * note: everything running before here was guaranteed
1922 * to choke driver model style diagnostics. from here
1923 * on, they can work ... except in cleanup paths that
1924 * kick in after the ep0 descriptor is closed.
1926 fd->f_op = &ep0_io_operations;
1932 spin_unlock_irq (&dev->lock);
1933 pr_debug ("%s: %s fail %Zd, %p\n", shortname, __func__, value, dev);
1940 dev_open (struct inode *inode, struct file *fd)
1942 struct dev_data *dev = inode->i_private;
1945 spin_lock_irq(&dev->lock);
1946 if (dev->state == STATE_DEV_DISABLED) {
1948 dev->state = STATE_DEV_OPENED;
1949 fd->private_data = dev;
1953 spin_unlock_irq(&dev->lock);
1957 static const struct file_operations dev_init_operations = {
1958 .llseek = no_llseek,
1961 .write = dev_config,
1962 .fasync = ep0_fasync,
1963 .unlocked_ioctl = dev_ioctl,
1964 .release = dev_release,
1967 /*----------------------------------------------------------------------*/
1969 /* FILESYSTEM AND SUPERBLOCK OPERATIONS
1971 * Mounting the filesystem creates a controller file, used first for
1972 * device configuration then later for event monitoring.
1976 /* FIXME PAM etc could set this security policy without mount options
1977 * if epfiles inherited ownership and permissons from ep0 ...
1980 static unsigned default_uid;
1981 static unsigned default_gid;
1982 static unsigned default_perm = S_IRUSR | S_IWUSR;
1984 module_param (default_uid, uint, 0644);
1985 module_param (default_gid, uint, 0644);
1986 module_param (default_perm, uint, 0644);
1989 static struct inode *
1990 gadgetfs_make_inode (struct super_block *sb,
1991 void *data, const struct file_operations *fops,
1994 struct inode *inode = new_inode (sb);
1997 inode->i_ino = get_next_ino();
1998 inode->i_mode = mode;
1999 inode->i_uid = make_kuid(&init_user_ns, default_uid);
2000 inode->i_gid = make_kgid(&init_user_ns, default_gid);
2001 inode->i_atime = inode->i_mtime = inode->i_ctime
2003 inode->i_private = data;
2004 inode->i_fop = fops;
2009 /* creates in fs root directory, so non-renamable and non-linkable.
2010 * so inode and dentry are paired, until device reconfig.
2012 static struct dentry *
2013 gadgetfs_create_file (struct super_block *sb, char const *name,
2014 void *data, const struct file_operations *fops)
2016 struct dentry *dentry;
2017 struct inode *inode;
2019 dentry = d_alloc_name(sb->s_root, name);
2023 inode = gadgetfs_make_inode (sb, data, fops,
2024 S_IFREG | (default_perm & S_IRWXUGO));
2029 d_add (dentry, inode);
2033 static const struct super_operations gadget_fs_operations = {
2034 .statfs = simple_statfs,
2035 .drop_inode = generic_delete_inode,
2039 gadgetfs_fill_super (struct super_block *sb, void *opts, int silent)
2041 struct inode *inode;
2042 struct dev_data *dev;
2047 /* fake probe to determine $CHIP */
2049 usb_gadget_probe_driver(&probe_driver);
2054 sb->s_blocksize = PAGE_CACHE_SIZE;
2055 sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
2056 sb->s_magic = GADGETFS_MAGIC;
2057 sb->s_op = &gadget_fs_operations;
2058 sb->s_time_gran = 1;
2061 inode = gadgetfs_make_inode (sb,
2062 NULL, &simple_dir_operations,
2063 S_IFDIR | S_IRUGO | S_IXUGO);
2066 inode->i_op = &simple_dir_inode_operations;
2067 if (!(sb->s_root = d_make_root (inode)))
2070 /* the ep0 file is named after the controller we expect;
2071 * user mode code can use it for sanity checks, like we do.
2078 dev->dentry = gadgetfs_create_file(sb, CHIP, dev, &dev_init_operations);
2084 /* other endpoint files are available after hardware setup,
2085 * from binding to a controller.
2094 /* "mount -t gadgetfs path /dev/gadget" ends up here */
2095 static struct dentry *
2096 gadgetfs_mount (struct file_system_type *t, int flags,
2097 const char *path, void *opts)
2099 return mount_single (t, flags, opts, gadgetfs_fill_super);
2103 gadgetfs_kill_sb (struct super_block *sb)
2105 kill_litter_super (sb);
2107 put_dev (the_device);
2112 /*----------------------------------------------------------------------*/
2114 static struct file_system_type gadgetfs_type = {
2115 .owner = THIS_MODULE,
2117 .mount = gadgetfs_mount,
2118 .kill_sb = gadgetfs_kill_sb,
2120 MODULE_ALIAS_FS("gadgetfs");
2122 /*----------------------------------------------------------------------*/
2124 static int __init init (void)
2128 status = register_filesystem (&gadgetfs_type);
2130 pr_info ("%s: %s, version " DRIVER_VERSION "\n",
2131 shortname, driver_desc);
2136 static void __exit cleanup (void)
2138 pr_debug ("unregister %s\n", shortname);
2139 unregister_filesystem (&gadgetfs_type);
2141 module_exit (cleanup);