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.
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
17 * You should have received a copy of the GNU General Public License
18 * along with this program; if not, write to the Free Software
19 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
23 // #define DEBUG /* data to help fault diagnosis */
24 // #define VERBOSE /* extra debug messages (success too) */
26 #include <linux/init.h>
27 #include <linux/module.h>
29 #include <linux/pagemap.h>
30 #include <linux/uts.h>
31 #include <linux/wait.h>
32 #include <linux/compiler.h>
33 #include <asm/uaccess.h>
34 #include <linux/slab.h>
35 #include <linux/poll.h>
37 #include <linux/device.h>
38 #include <linux/moduleparam.h>
40 #include <linux/usb_gadgetfs.h>
41 #include <linux/usb_gadget.h>
45 * The gadgetfs API maps each endpoint to a file descriptor so that you
46 * can use standard synchronous read/write calls for I/O. There's some
47 * O_NONBLOCK and O_ASYNC/FASYNC style i/o support. Example usermode
48 * drivers show how this works in practice. You can also use AIO to
49 * eliminate I/O gaps between requests, to help when streaming data.
51 * Key parts that must be USB-specific are protocols defining how the
52 * read/write operations relate to the hardware state machines. There
53 * are two types of files. One type is for the device, implementing ep0.
54 * The other type is for each IN or OUT endpoint. In both cases, the
55 * user mode driver must configure the hardware before using it.
57 * - First, dev_config() is called when /dev/gadget/$CHIP is configured
58 * (by writing configuration and device descriptors). Afterwards it
59 * may serve as a source of device events, used to handle all control
60 * requests other than basic enumeration.
62 * - Then either immediately, or after a SET_CONFIGURATION control request,
63 * ep_config() is called when each /dev/gadget/ep* file is configured
64 * (by writing endpoint descriptors). Afterwards these files are used
65 * to write() IN data or to read() OUT data. To halt the endpoint, a
66 * "wrong direction" request is issued (like reading an IN endpoint).
68 * Unlike "usbfs" the only ioctl()s are for things that are rare, and maybe
69 * not possible on all hardware. For example, precise fault handling with
70 * respect to data left in endpoint fifos after aborted operations; or
71 * selective clearing of endpoint halts, to implement SET_INTERFACE.
74 #define DRIVER_DESC "USB Gadget filesystem"
75 #define DRIVER_VERSION "24 Aug 2004"
77 static const char driver_desc [] = DRIVER_DESC;
78 static const char shortname [] = "gadgetfs";
80 MODULE_DESCRIPTION (DRIVER_DESC);
81 MODULE_AUTHOR ("David Brownell");
82 MODULE_LICENSE ("GPL");
85 /*----------------------------------------------------------------------*/
87 #define GADGETFS_MAGIC 0xaee71ee7
88 #define DMA_ADDR_INVALID (~(dma_addr_t)0)
90 /* /dev/gadget/$CHIP represents ep0 and the whole device */
92 /* DISBLED is the initial state.
94 STATE_DEV_DISABLED = 0,
96 /* Only one open() of /dev/gadget/$CHIP; only one file tracks
97 * ep0/device i/o modes and binding to the controller. Driver
98 * must always write descriptors to initialize the device, then
99 * the device becomes UNCONNECTED until enumeration.
103 /* From then on, ep0 fd is in either of two basic modes:
104 * - (UN)CONNECTED: read usb_gadgetfs_event(s) from it
105 * - SETUP: read/write will transfer control data and succeed;
106 * or if "wrong direction", performs protocol stall
112 /* UNBOUND means the driver closed ep0, so the device won't be
113 * accessible again (DEV_DISABLED) until all fds are closed.
118 /* enough for the whole queue: most events invalidate others */
124 enum ep0_state state;
125 struct usb_gadgetfs_event event [N_EVENT];
127 struct fasync_struct *fasync;
130 /* drivers reading ep0 MUST handle control requests (SETUP)
131 * reported that way; else the host will time out.
133 unsigned usermode_setup : 1,
139 unsigned setup_wLength;
141 /* the rest is basically write-once */
142 struct usb_config_descriptor *config, *hs_config;
143 struct usb_device_descriptor *dev;
144 struct usb_request *req;
145 struct usb_gadget *gadget;
146 struct list_head epfiles;
148 wait_queue_head_t wait;
149 struct super_block *sb;
150 struct dentry *dentry;
152 /* except this scratch i/o buffer for ep0 */
156 static inline void get_dev (struct dev_data *data)
158 atomic_inc (&data->count);
161 static void put_dev (struct dev_data *data)
163 if (likely (!atomic_dec_and_test (&data->count)))
165 /* needs no more cleanup */
166 BUG_ON (waitqueue_active (&data->wait));
170 static struct dev_data *dev_new (void)
172 struct dev_data *dev;
174 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
177 dev->state = STATE_DEV_DISABLED;
178 atomic_set (&dev->count, 1);
179 spin_lock_init (&dev->lock);
180 INIT_LIST_HEAD (&dev->epfiles);
181 init_waitqueue_head (&dev->wait);
185 /*----------------------------------------------------------------------*/
187 /* other /dev/gadget/$ENDPOINT files represent endpoints */
189 STATE_EP_DISABLED = 0,
191 STATE_EP_DEFER_ENABLE,
197 struct semaphore lock;
200 struct dev_data *dev;
201 /* must hold dev->lock before accessing ep or req */
203 struct usb_request *req;
206 struct usb_endpoint_descriptor desc, hs_desc;
207 struct list_head epfiles;
208 wait_queue_head_t wait;
209 struct dentry *dentry;
213 static inline void get_ep (struct ep_data *data)
215 atomic_inc (&data->count);
218 static void put_ep (struct ep_data *data)
220 if (likely (!atomic_dec_and_test (&data->count)))
223 /* needs no more cleanup */
224 BUG_ON (!list_empty (&data->epfiles));
225 BUG_ON (waitqueue_active (&data->wait));
229 /*----------------------------------------------------------------------*/
231 /* most "how to use the hardware" policy choices are in userspace:
232 * mapping endpoint roles (which the driver needs) to the capabilities
233 * which the usb controller has. most of those capabilities are exposed
234 * implicitly, starting with the driver name and then endpoint names.
237 static const char *CHIP;
239 /*----------------------------------------------------------------------*/
241 /* NOTE: don't use dev_printk calls before binding to the gadget
242 * at the end of ep0 configuration, or after unbind.
245 /* too wordy: dev_printk(level , &(d)->gadget->dev , fmt , ## args) */
246 #define xprintk(d,level,fmt,args...) \
247 printk(level "%s: " fmt , shortname , ## args)
250 #define DBG(dev,fmt,args...) \
251 xprintk(dev , KERN_DEBUG , fmt , ## args)
253 #define DBG(dev,fmt,args...) \
260 #define VDEBUG(dev,fmt,args...) \
264 #define ERROR(dev,fmt,args...) \
265 xprintk(dev , KERN_ERR , fmt , ## args)
266 #define WARN(dev,fmt,args...) \
267 xprintk(dev , KERN_WARNING , fmt , ## args)
268 #define INFO(dev,fmt,args...) \
269 xprintk(dev , KERN_INFO , fmt , ## args)
272 /*----------------------------------------------------------------------*/
274 /* SYNCHRONOUS ENDPOINT OPERATIONS (bulk/intr/iso)
276 * After opening, configure non-control endpoints. Then use normal
277 * stream read() and write() requests; and maybe ioctl() to get more
278 * precise FIFO status when recovering from cancellation.
281 static void epio_complete (struct usb_ep *ep, struct usb_request *req)
283 struct ep_data *epdata = ep->driver_data;
288 epdata->status = req->status;
290 epdata->status = req->actual;
291 complete ((struct completion *)req->context);
294 /* tasklock endpoint, returning when it's connected.
295 * still need dev->lock to use epdata->ep.
298 get_ready_ep (unsigned f_flags, struct ep_data *epdata)
302 if (f_flags & O_NONBLOCK) {
303 if (down_trylock (&epdata->lock) != 0)
305 if (epdata->state != STATE_EP_ENABLED) {
314 if ((val = down_interruptible (&epdata->lock)) < 0)
317 switch (epdata->state) {
318 case STATE_EP_ENABLED:
320 case STATE_EP_DEFER_ENABLE:
321 DBG (epdata->dev, "%s wait for host\n", epdata->name);
322 if ((val = wait_event_interruptible (epdata->wait,
323 epdata->state != STATE_EP_DEFER_ENABLE
324 || epdata->dev->state == STATE_DEV_UNBOUND
328 // case STATE_EP_DISABLED: /* "can't happen" */
329 // case STATE_EP_READY: /* "can't happen" */
330 default: /* error! */
331 pr_debug ("%s: ep %p not available, state %d\n",
332 shortname, epdata, epdata->state);
334 case STATE_EP_UNBOUND: /* clean disconnect */
343 ep_io (struct ep_data *epdata, void *buf, unsigned len)
345 DECLARE_COMPLETION (done);
348 spin_lock_irq (&epdata->dev->lock);
349 if (likely (epdata->ep != NULL)) {
350 struct usb_request *req = epdata->req;
352 req->context = &done;
353 req->complete = epio_complete;
356 value = usb_ep_queue (epdata->ep, req, GFP_ATOMIC);
359 spin_unlock_irq (&epdata->dev->lock);
361 if (likely (value == 0)) {
362 value = wait_event_interruptible (done.wait, done.done);
364 spin_lock_irq (&epdata->dev->lock);
365 if (likely (epdata->ep != NULL)) {
366 DBG (epdata->dev, "%s i/o interrupted\n",
368 usb_ep_dequeue (epdata->ep, epdata->req);
369 spin_unlock_irq (&epdata->dev->lock);
371 wait_event (done.wait, done.done);
372 if (epdata->status == -ECONNRESET)
373 epdata->status = -EINTR;
375 spin_unlock_irq (&epdata->dev->lock);
377 DBG (epdata->dev, "endpoint gone\n");
378 epdata->status = -ENODEV;
381 return epdata->status;
387 /* handle a synchronous OUT bulk/intr/iso transfer */
389 ep_read (struct file *fd, char __user *buf, size_t len, loff_t *ptr)
391 struct ep_data *data = fd->private_data;
395 if ((value = get_ready_ep (fd->f_flags, data)) < 0)
398 /* halt any endpoint by doing a "wrong direction" i/o call */
399 if (data->desc.bEndpointAddress & USB_DIR_IN) {
400 if ((data->desc.bmAttributes & USB_ENDPOINT_XFERTYPE_MASK)
401 == USB_ENDPOINT_XFER_ISOC)
403 DBG (data->dev, "%s halt\n", data->name);
404 spin_lock_irq (&data->dev->lock);
405 if (likely (data->ep != NULL))
406 usb_ep_set_halt (data->ep);
407 spin_unlock_irq (&data->dev->lock);
412 /* FIXME readahead for O_NONBLOCK and poll(); careful with ZLPs */
415 kbuf = kmalloc (len, SLAB_KERNEL);
416 if (unlikely (!kbuf))
419 value = ep_io (data, kbuf, len);
420 VDEBUG (data->dev, "%s read %zu OUT, status %d\n",
421 data->name, len, (int) value);
422 if (value >= 0 && copy_to_user (buf, kbuf, value))
431 /* handle a synchronous IN bulk/intr/iso transfer */
433 ep_write (struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
435 struct ep_data *data = fd->private_data;
439 if ((value = get_ready_ep (fd->f_flags, data)) < 0)
442 /* halt any endpoint by doing a "wrong direction" i/o call */
443 if (!(data->desc.bEndpointAddress & USB_DIR_IN)) {
444 if ((data->desc.bmAttributes & USB_ENDPOINT_XFERTYPE_MASK)
445 == USB_ENDPOINT_XFER_ISOC)
447 DBG (data->dev, "%s halt\n", data->name);
448 spin_lock_irq (&data->dev->lock);
449 if (likely (data->ep != NULL))
450 usb_ep_set_halt (data->ep);
451 spin_unlock_irq (&data->dev->lock);
456 /* FIXME writebehind for O_NONBLOCK and poll(), qlen = 1 */
459 kbuf = kmalloc (len, SLAB_KERNEL);
462 if (copy_from_user (kbuf, buf, len)) {
467 value = ep_io (data, kbuf, len);
468 VDEBUG (data->dev, "%s write %zu IN, status %d\n",
469 data->name, len, (int) value);
477 ep_release (struct inode *inode, struct file *fd)
479 struct ep_data *data = fd->private_data;
482 if ((value = down_interruptible(&data->lock)) < 0)
485 /* clean up if this can be reopened */
486 if (data->state != STATE_EP_UNBOUND) {
487 data->state = STATE_EP_DISABLED;
488 data->desc.bDescriptorType = 0;
489 data->hs_desc.bDescriptorType = 0;
490 usb_ep_disable(data->ep);
497 static int ep_ioctl (struct inode *inode, struct file *fd,
498 unsigned code, unsigned long value)
500 struct ep_data *data = fd->private_data;
503 if ((status = get_ready_ep (fd->f_flags, data)) < 0)
506 spin_lock_irq (&data->dev->lock);
507 if (likely (data->ep != NULL)) {
509 case GADGETFS_FIFO_STATUS:
510 status = usb_ep_fifo_status (data->ep);
512 case GADGETFS_FIFO_FLUSH:
513 usb_ep_fifo_flush (data->ep);
515 case GADGETFS_CLEAR_HALT:
516 status = usb_ep_clear_halt (data->ep);
523 spin_unlock_irq (&data->dev->lock);
528 /*----------------------------------------------------------------------*/
530 /* ASYNCHRONOUS ENDPOINT I/O OPERATIONS (bulk/intr/iso) */
533 struct usb_request *req;
534 struct ep_data *epdata;
536 char __user *ubuf; /* NULL for writes */
540 static int ep_aio_cancel(struct kiocb *iocb, struct io_event *e)
542 struct kiocb_priv *priv = iocb->private;
543 struct ep_data *epdata;
547 epdata = priv->epdata;
548 // spin_lock(&epdata->dev->lock);
549 kiocbSetCancelled(iocb);
550 if (likely(epdata && epdata->ep && priv->req))
551 value = usb_ep_dequeue (epdata->ep, priv->req);
554 // spin_unlock(&epdata->dev->lock);
561 static ssize_t ep_aio_read_retry(struct kiocb *iocb)
563 struct kiocb_priv *priv = iocb->private;
564 ssize_t status = priv->actual;
566 /* we "retry" to get the right mm context for this: */
567 status = copy_to_user(priv->ubuf, priv->buf, priv->actual);
568 if (unlikely(0 != status))
571 status = priv->actual;
577 static void ep_aio_complete(struct usb_ep *ep, struct usb_request *req)
579 struct kiocb *iocb = req->context;
580 struct kiocb_priv *priv = iocb->private;
581 struct ep_data *epdata = priv->epdata;
583 /* lock against disconnect (and ideally, cancel) */
584 spin_lock(&epdata->dev->lock);
587 if (priv->ubuf == NULL
588 || unlikely(req->actual == 0)
589 || unlikely(kiocbIsCancelled(iocb))) {
592 iocb->private = NULL;
593 /* aio_complete() reports bytes-transferred _and_ faults */
594 if (unlikely(kiocbIsCancelled(iocb)))
598 req->actual ? req->actual : req->status,
601 /* retry() won't report both; so we hide some faults */
602 if (unlikely(0 != req->status))
603 DBG(epdata->dev, "%s fault %d len %d\n",
604 ep->name, req->status, req->actual);
606 priv->buf = req->buf;
607 priv->actual = req->actual;
610 spin_unlock(&epdata->dev->lock);
612 usb_ep_free_request(ep, req);
621 struct ep_data *epdata,
625 struct kiocb_priv *priv;
626 struct usb_request *req;
629 priv = kmalloc(sizeof *priv, GFP_KERNEL);
636 iocb->private = priv;
639 value = get_ready_ep(iocb->ki_filp->f_flags, epdata);
640 if (unlikely(value < 0)) {
645 iocb->ki_cancel = ep_aio_cancel;
647 priv->epdata = epdata;
650 /* each kiocb is coupled to one usb_request, but we can't
651 * allocate or submit those if the host disconnected.
653 spin_lock_irq(&epdata->dev->lock);
654 if (likely(epdata->ep)) {
655 req = usb_ep_alloc_request(epdata->ep, GFP_ATOMIC);
660 req->complete = ep_aio_complete;
662 value = usb_ep_queue(epdata->ep, req, GFP_ATOMIC);
663 if (unlikely(0 != value))
664 usb_ep_free_request(epdata->ep, req);
669 spin_unlock_irq(&epdata->dev->lock);
673 if (unlikely(value)) {
677 value = (ubuf ? -EIOCBRETRY : -EIOCBQUEUED);
682 ep_aio_read(struct kiocb *iocb, char __user *ubuf, size_t len, loff_t o)
684 struct ep_data *epdata = iocb->ki_filp->private_data;
687 if (unlikely(epdata->desc.bEndpointAddress & USB_DIR_IN))
689 buf = kmalloc(len, GFP_KERNEL);
692 iocb->ki_retry = ep_aio_read_retry;
693 return ep_aio_rwtail(iocb, buf, len, epdata, ubuf);
697 ep_aio_write(struct kiocb *iocb, const char __user *ubuf, size_t len, loff_t o)
699 struct ep_data *epdata = iocb->ki_filp->private_data;
702 if (unlikely(!(epdata->desc.bEndpointAddress & USB_DIR_IN)))
704 buf = kmalloc(len, GFP_KERNEL);
707 if (unlikely(copy_from_user(buf, ubuf, len) != 0)) {
711 return ep_aio_rwtail(iocb, buf, len, epdata, NULL);
714 /*----------------------------------------------------------------------*/
716 /* used after endpoint configuration */
717 static const struct file_operations ep_io_operations = {
718 .owner = THIS_MODULE,
724 .release = ep_release,
726 .aio_read = ep_aio_read,
727 .aio_write = ep_aio_write,
730 /* ENDPOINT INITIALIZATION
732 * fd = open ("/dev/gadget/$ENDPOINT", O_RDWR)
733 * status = write (fd, descriptors, sizeof descriptors)
735 * That write establishes the endpoint configuration, configuring
736 * the controller to process bulk, interrupt, or isochronous transfers
737 * at the right maxpacket size, and so on.
739 * The descriptors are message type 1, identified by a host order u32
740 * at the beginning of what's written. Descriptor order is: full/low
741 * speed descriptor, then optional high speed descriptor.
744 ep_config (struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
746 struct ep_data *data = fd->private_data;
749 int value, length = len;
751 if ((value = down_interruptible (&data->lock)) < 0)
754 if (data->state != STATE_EP_READY) {
760 if (len < USB_DT_ENDPOINT_SIZE + 4)
763 /* we might need to change message format someday */
764 if (copy_from_user (&tag, buf, 4)) {
768 DBG(data->dev, "config %s, bad tag %d\n", data->name, tag);
774 /* NOTE: audio endpoint extensions not accepted here;
775 * just don't include the extra bytes.
778 /* full/low speed descriptor, then high speed */
779 if (copy_from_user (&data->desc, buf, USB_DT_ENDPOINT_SIZE)) {
782 if (data->desc.bLength != USB_DT_ENDPOINT_SIZE
783 || data->desc.bDescriptorType != USB_DT_ENDPOINT)
785 if (len != USB_DT_ENDPOINT_SIZE) {
786 if (len != 2 * USB_DT_ENDPOINT_SIZE)
788 if (copy_from_user (&data->hs_desc, buf + USB_DT_ENDPOINT_SIZE,
789 USB_DT_ENDPOINT_SIZE)) {
792 if (data->hs_desc.bLength != USB_DT_ENDPOINT_SIZE
793 || data->hs_desc.bDescriptorType
794 != USB_DT_ENDPOINT) {
795 DBG(data->dev, "config %s, bad hs length or type\n",
801 spin_lock_irq (&data->dev->lock);
802 if (data->dev->state == STATE_DEV_UNBOUND) {
805 } else if ((ep = data->ep) == NULL) {
809 switch (data->dev->gadget->speed) {
812 value = usb_ep_enable (ep, &data->desc);
814 data->state = STATE_EP_ENABLED;
816 #ifdef CONFIG_USB_GADGET_DUALSPEED
818 /* fails if caller didn't provide that descriptor... */
819 value = usb_ep_enable (ep, &data->hs_desc);
821 data->state = STATE_EP_ENABLED;
825 DBG (data->dev, "unconnected, %s init deferred\n",
827 data->state = STATE_EP_DEFER_ENABLE;
830 fd->f_op = &ep_io_operations;
834 spin_unlock_irq (&data->dev->lock);
837 data->desc.bDescriptorType = 0;
838 data->hs_desc.bDescriptorType = 0;
851 ep_open (struct inode *inode, struct file *fd)
853 struct ep_data *data = inode->i_private;
856 if (down_interruptible (&data->lock) != 0)
858 spin_lock_irq (&data->dev->lock);
859 if (data->dev->state == STATE_DEV_UNBOUND)
861 else if (data->state == STATE_EP_DISABLED) {
863 data->state = STATE_EP_READY;
865 fd->private_data = data;
866 VDEBUG (data->dev, "%s ready\n", data->name);
868 DBG (data->dev, "%s state %d\n",
869 data->name, data->state);
870 spin_unlock_irq (&data->dev->lock);
875 /* used before endpoint configuration */
876 static const struct file_operations ep_config_operations = {
877 .owner = THIS_MODULE,
882 .release = ep_release,
885 /*----------------------------------------------------------------------*/
887 /* EP0 IMPLEMENTATION can be partly in userspace.
889 * Drivers that use this facility receive various events, including
890 * control requests the kernel doesn't handle. Drivers that don't
891 * use this facility may be too simple-minded for real applications.
894 static inline void ep0_readable (struct dev_data *dev)
896 wake_up (&dev->wait);
897 kill_fasync (&dev->fasync, SIGIO, POLL_IN);
900 static void clean_req (struct usb_ep *ep, struct usb_request *req)
902 struct dev_data *dev = ep->driver_data;
904 if (req->buf != dev->rbuf) {
905 usb_ep_free_buffer (ep, req->buf, req->dma, req->length);
906 req->buf = dev->rbuf;
907 req->dma = DMA_ADDR_INVALID;
909 req->complete = epio_complete;
910 dev->setup_out_ready = 0;
913 static void ep0_complete (struct usb_ep *ep, struct usb_request *req)
915 struct dev_data *dev = ep->driver_data;
918 /* for control OUT, data must still get to userspace */
919 if (!dev->setup_in) {
920 dev->setup_out_error = (req->status != 0);
921 if (!dev->setup_out_error)
923 dev->setup_out_ready = 1;
925 } else if (dev->state == STATE_SETUP)
926 dev->state = STATE_CONNECTED;
928 /* clean up as appropriate */
929 if (free && req->buf != &dev->rbuf)
931 req->complete = epio_complete;
934 static int setup_req (struct usb_ep *ep, struct usb_request *req, u16 len)
936 struct dev_data *dev = ep->driver_data;
938 if (dev->setup_out_ready) {
939 DBG (dev, "ep0 request busy!\n");
942 if (len > sizeof (dev->rbuf))
943 req->buf = usb_ep_alloc_buffer (ep, len, &req->dma, GFP_ATOMIC);
945 req->buf = dev->rbuf;
948 req->complete = ep0_complete;
955 ep0_read (struct file *fd, char __user *buf, size_t len, loff_t *ptr)
957 struct dev_data *dev = fd->private_data;
959 enum ep0_state state;
961 spin_lock_irq (&dev->lock);
963 /* report fd mode change before acting on it */
964 if (dev->setup_abort) {
965 dev->setup_abort = 0;
970 /* control DATA stage */
971 if ((state = dev->state) == STATE_SETUP) {
973 if (dev->setup_in) { /* stall IN */
974 VDEBUG(dev, "ep0in stall\n");
975 (void) usb_ep_set_halt (dev->gadget->ep0);
977 dev->state = STATE_CONNECTED;
979 } else if (len == 0) { /* ack SET_CONFIGURATION etc */
980 struct usb_ep *ep = dev->gadget->ep0;
981 struct usb_request *req = dev->req;
983 if ((retval = setup_req (ep, req, 0)) == 0)
984 retval = usb_ep_queue (ep, req, GFP_ATOMIC);
985 dev->state = STATE_CONNECTED;
987 /* assume that was SET_CONFIGURATION */
988 if (dev->current_config) {
990 #ifdef CONFIG_USB_GADGET_DUALSPEED
991 if (dev->gadget->speed == USB_SPEED_HIGH)
992 power = dev->hs_config->bMaxPower;
995 power = dev->config->bMaxPower;
996 usb_gadget_vbus_draw(dev->gadget, 2 * power);
999 } else { /* collect OUT data */
1000 if ((fd->f_flags & O_NONBLOCK) != 0
1001 && !dev->setup_out_ready) {
1005 spin_unlock_irq (&dev->lock);
1006 retval = wait_event_interruptible (dev->wait,
1007 dev->setup_out_ready != 0);
1009 /* FIXME state could change from under us */
1010 spin_lock_irq (&dev->lock);
1013 if (dev->setup_out_error)
1016 len = min (len, (size_t)dev->req->actual);
1017 // FIXME don't call this with the spinlock held ...
1018 if (copy_to_user (buf, &dev->req->buf, len))
1020 clean_req (dev->gadget->ep0, dev->req);
1021 /* NOTE userspace can't yet choose to stall */
1027 /* else normal: return event data */
1028 if (len < sizeof dev->event [0]) {
1032 len -= len % sizeof (struct usb_gadgetfs_event);
1033 dev->usermode_setup = 1;
1036 /* return queued events right away */
1037 if (dev->ev_next != 0) {
1039 int tmp = dev->ev_next;
1041 len = min (len, tmp * sizeof (struct usb_gadgetfs_event));
1042 n = len / sizeof (struct usb_gadgetfs_event);
1044 /* ep0 can't deliver events when STATE_SETUP */
1045 for (i = 0; i < n; i++) {
1046 if (dev->event [i].type == GADGETFS_SETUP) {
1048 len *= sizeof (struct usb_gadgetfs_event);
1053 spin_unlock_irq (&dev->lock);
1054 if (copy_to_user (buf, &dev->event, len))
1059 len /= sizeof (struct usb_gadgetfs_event);
1061 /* NOTE this doesn't guard against broken drivers;
1062 * concurrent ep0 readers may lose events.
1064 spin_lock_irq (&dev->lock);
1065 dev->ev_next -= len;
1066 if (dev->ev_next != 0)
1067 memmove (&dev->event, &dev->event [len],
1068 sizeof (struct usb_gadgetfs_event)
1071 dev->state = STATE_SETUP;
1072 spin_unlock_irq (&dev->lock);
1076 if (fd->f_flags & O_NONBLOCK) {
1083 DBG (dev, "fail %s, state %d\n", __FUNCTION__, state);
1086 case STATE_UNCONNECTED:
1087 case STATE_CONNECTED:
1088 spin_unlock_irq (&dev->lock);
1089 DBG (dev, "%s wait\n", __FUNCTION__);
1091 /* wait for events */
1092 retval = wait_event_interruptible (dev->wait,
1096 spin_lock_irq (&dev->lock);
1101 spin_unlock_irq (&dev->lock);
1105 static struct usb_gadgetfs_event *
1106 next_event (struct dev_data *dev, enum usb_gadgetfs_event_type type)
1108 struct usb_gadgetfs_event *event;
1112 /* these events purge the queue */
1113 case GADGETFS_DISCONNECT:
1114 if (dev->state == STATE_SETUP)
1115 dev->setup_abort = 1;
1117 case GADGETFS_CONNECT:
1120 case GADGETFS_SETUP: /* previous request timed out */
1121 case GADGETFS_SUSPEND: /* same effect */
1122 /* these events can't be repeated */
1123 for (i = 0; i != dev->ev_next; i++) {
1124 if (dev->event [i].type != type)
1126 DBG (dev, "discard old event %d\n", type);
1128 if (i == dev->ev_next)
1130 /* indices start at zero, for simplicity */
1131 memmove (&dev->event [i], &dev->event [i + 1],
1132 sizeof (struct usb_gadgetfs_event)
1133 * (dev->ev_next - i));
1139 event = &dev->event [dev->ev_next++];
1140 BUG_ON (dev->ev_next > N_EVENT);
1141 VDEBUG (dev, "ev %d, next %d\n", type, dev->ev_next);
1142 memset (event, 0, sizeof *event);
1148 ep0_write (struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
1150 struct dev_data *dev = fd->private_data;
1151 ssize_t retval = -ESRCH;
1153 spin_lock_irq (&dev->lock);
1155 /* report fd mode change before acting on it */
1156 if (dev->setup_abort) {
1157 dev->setup_abort = 0;
1160 /* data and/or status stage for control request */
1161 } else if (dev->state == STATE_SETUP) {
1163 /* IN DATA+STATUS caller makes len <= wLength */
1164 if (dev->setup_in) {
1165 retval = setup_req (dev->gadget->ep0, dev->req, len);
1167 spin_unlock_irq (&dev->lock);
1168 if (copy_from_user (dev->req->buf, buf, len))
1171 if (len < dev->setup_wLength)
1173 retval = usb_ep_queue (
1174 dev->gadget->ep0, dev->req,
1178 spin_lock_irq (&dev->lock);
1179 clean_req (dev->gadget->ep0, dev->req);
1180 spin_unlock_irq (&dev->lock);
1187 /* can stall some OUT transfers */
1188 } else if (dev->setup_can_stall) {
1189 VDEBUG(dev, "ep0out stall\n");
1190 (void) usb_ep_set_halt (dev->gadget->ep0);
1192 dev->state = STATE_CONNECTED;
1194 DBG(dev, "bogus ep0out stall!\n");
1197 DBG (dev, "fail %s, state %d\n", __FUNCTION__, dev->state);
1199 spin_unlock_irq (&dev->lock);
1204 ep0_fasync (int f, struct file *fd, int on)
1206 struct dev_data *dev = fd->private_data;
1207 // caller must F_SETOWN before signal delivery happens
1208 VDEBUG (dev, "%s %s\n", __FUNCTION__, on ? "on" : "off");
1209 return fasync_helper (f, fd, on, &dev->fasync);
1212 static struct usb_gadget_driver gadgetfs_driver;
1215 dev_release (struct inode *inode, struct file *fd)
1217 struct dev_data *dev = fd->private_data;
1219 /* closing ep0 === shutdown all */
1221 usb_gadget_unregister_driver (&gadgetfs_driver);
1223 /* at this point "good" hardware has disconnected the
1224 * device from USB; the host won't see it any more.
1225 * alternatively, all host requests will time out.
1228 fasync_helper (-1, fd, 0, &dev->fasync);
1233 /* other endpoints were all decoupled from this device */
1234 dev->state = STATE_DEV_DISABLED;
1239 ep0_poll (struct file *fd, poll_table *wait)
1241 struct dev_data *dev = fd->private_data;
1244 poll_wait(fd, &dev->wait, wait);
1246 spin_lock_irq (&dev->lock);
1248 /* report fd mode change before acting on it */
1249 if (dev->setup_abort) {
1250 dev->setup_abort = 0;
1255 if (dev->state == STATE_SETUP) {
1256 if (dev->setup_in || dev->setup_can_stall)
1259 if (dev->ev_next != 0)
1263 spin_unlock_irq(&dev->lock);
1267 static int dev_ioctl (struct inode *inode, struct file *fd,
1268 unsigned code, unsigned long value)
1270 struct dev_data *dev = fd->private_data;
1271 struct usb_gadget *gadget = dev->gadget;
1273 if (gadget->ops->ioctl)
1274 return gadget->ops->ioctl (gadget, code, value);
1278 /* used after device configuration */
1279 static const struct file_operations ep0_io_operations = {
1280 .owner = THIS_MODULE,
1281 .llseek = no_llseek,
1285 .fasync = ep0_fasync,
1288 .release = dev_release,
1291 /*----------------------------------------------------------------------*/
1293 /* The in-kernel gadget driver handles most ep0 issues, in particular
1294 * enumerating the single configuration (as provided from user space).
1296 * Unrecognized ep0 requests may be handled in user space.
1299 #ifdef CONFIG_USB_GADGET_DUALSPEED
1300 static void make_qualifier (struct dev_data *dev)
1302 struct usb_qualifier_descriptor qual;
1303 struct usb_device_descriptor *desc;
1305 qual.bLength = sizeof qual;
1306 qual.bDescriptorType = USB_DT_DEVICE_QUALIFIER;
1307 qual.bcdUSB = __constant_cpu_to_le16 (0x0200);
1310 qual.bDeviceClass = desc->bDeviceClass;
1311 qual.bDeviceSubClass = desc->bDeviceSubClass;
1312 qual.bDeviceProtocol = desc->bDeviceProtocol;
1314 /* assumes ep0 uses the same value for both speeds ... */
1315 qual.bMaxPacketSize0 = desc->bMaxPacketSize0;
1317 qual.bNumConfigurations = 1;
1320 memcpy (dev->rbuf, &qual, sizeof qual);
1325 config_buf (struct dev_data *dev, u8 type, unsigned index)
1328 #ifdef CONFIG_USB_GADGET_DUALSPEED
1332 /* only one configuration */
1336 #ifdef CONFIG_USB_GADGET_DUALSPEED
1337 hs = (dev->gadget->speed == USB_SPEED_HIGH);
1338 if (type == USB_DT_OTHER_SPEED_CONFIG)
1341 dev->req->buf = dev->hs_config;
1342 len = le16_to_cpup (&dev->hs_config->wTotalLength);
1346 dev->req->buf = dev->config;
1347 len = le16_to_cpup (&dev->config->wTotalLength);
1349 ((u8 *)dev->req->buf) [1] = type;
1354 gadgetfs_setup (struct usb_gadget *gadget, const struct usb_ctrlrequest *ctrl)
1356 struct dev_data *dev = get_gadget_data (gadget);
1357 struct usb_request *req = dev->req;
1358 int value = -EOPNOTSUPP;
1359 struct usb_gadgetfs_event *event;
1360 u16 w_value = le16_to_cpu(ctrl->wValue);
1361 u16 w_length = le16_to_cpu(ctrl->wLength);
1363 spin_lock (&dev->lock);
1364 dev->setup_abort = 0;
1365 if (dev->state == STATE_UNCONNECTED) {
1367 struct ep_data *data;
1369 dev->state = STATE_CONNECTED;
1370 dev->dev->bMaxPacketSize0 = gadget->ep0->maxpacket;
1372 #ifdef CONFIG_USB_GADGET_DUALSPEED
1373 if (gadget->speed == USB_SPEED_HIGH && dev->hs_config == 0) {
1374 ERROR (dev, "no high speed config??\n");
1377 #endif /* CONFIG_USB_GADGET_DUALSPEED */
1379 INFO (dev, "connected\n");
1380 event = next_event (dev, GADGETFS_CONNECT);
1381 event->u.speed = gadget->speed;
1384 list_for_each_entry (ep, &gadget->ep_list, ep_list) {
1385 data = ep->driver_data;
1386 /* ... down_trylock (&data->lock) ... */
1387 if (data->state != STATE_EP_DEFER_ENABLE)
1389 #ifdef CONFIG_USB_GADGET_DUALSPEED
1390 if (gadget->speed == USB_SPEED_HIGH)
1391 value = usb_ep_enable (ep, &data->hs_desc);
1393 #endif /* CONFIG_USB_GADGET_DUALSPEED */
1394 value = usb_ep_enable (ep, &data->desc);
1396 ERROR (dev, "deferred %s enable --> %d\n",
1400 data->state = STATE_EP_ENABLED;
1401 wake_up (&data->wait);
1402 DBG (dev, "woke up %s waiters\n", data->name);
1405 /* host may have given up waiting for response. we can miss control
1406 * requests handled lower down (device/endpoint status and features);
1407 * then ep0_{read,write} will report the wrong status. controller
1408 * driver will have aborted pending i/o.
1410 } else if (dev->state == STATE_SETUP)
1411 dev->setup_abort = 1;
1413 req->buf = dev->rbuf;
1414 req->dma = DMA_ADDR_INVALID;
1415 req->context = NULL;
1416 value = -EOPNOTSUPP;
1417 switch (ctrl->bRequest) {
1419 case USB_REQ_GET_DESCRIPTOR:
1420 if (ctrl->bRequestType != USB_DIR_IN)
1422 switch (w_value >> 8) {
1425 value = min (w_length, (u16) sizeof *dev->dev);
1426 req->buf = dev->dev;
1428 #ifdef CONFIG_USB_GADGET_DUALSPEED
1429 case USB_DT_DEVICE_QUALIFIER:
1430 if (!dev->hs_config)
1432 value = min (w_length, (u16)
1433 sizeof (struct usb_qualifier_descriptor));
1434 make_qualifier (dev);
1436 case USB_DT_OTHER_SPEED_CONFIG:
1440 value = config_buf (dev,
1444 value = min (w_length, (u16) value);
1449 default: // all others are errors
1454 /* currently one config, two speeds */
1455 case USB_REQ_SET_CONFIGURATION:
1456 if (ctrl->bRequestType != 0)
1458 if (0 == (u8) w_value) {
1460 dev->current_config = 0;
1461 usb_gadget_vbus_draw(gadget, 8 /* mA */ );
1462 // user mode expected to disable endpoints
1465 #ifdef CONFIG_USB_GADGET_DUALSPEED
1466 if (gadget->speed == USB_SPEED_HIGH) {
1467 config = dev->hs_config->bConfigurationValue;
1468 power = dev->hs_config->bMaxPower;
1472 config = dev->config->bConfigurationValue;
1473 power = dev->config->bMaxPower;
1476 if (config == (u8) w_value) {
1478 dev->current_config = config;
1479 usb_gadget_vbus_draw(gadget, 2 * power);
1483 /* report SET_CONFIGURATION like any other control request,
1484 * except that usermode may not stall this. the next
1485 * request mustn't be allowed start until this finishes:
1486 * endpoints and threads set up, etc.
1488 * NOTE: older PXA hardware (before PXA 255: without UDCCFR)
1489 * has bad/racey automagic that prevents synchronizing here.
1490 * even kernel mode drivers often miss them.
1493 INFO (dev, "configuration #%d\n", dev->current_config);
1494 if (dev->usermode_setup) {
1495 dev->setup_can_stall = 0;
1501 #ifndef CONFIG_USB_GADGETFS_PXA2XX
1502 /* PXA automagically handles this request too */
1503 case USB_REQ_GET_CONFIGURATION:
1504 if (ctrl->bRequestType != 0x80)
1506 *(u8 *)req->buf = dev->current_config;
1507 value = min (w_length, (u16) 1);
1513 VDEBUG (dev, "%s req%02x.%02x v%04x i%04x l%d\n",
1514 dev->usermode_setup ? "delegate" : "fail",
1515 ctrl->bRequestType, ctrl->bRequest,
1516 w_value, le16_to_cpu(ctrl->wIndex), w_length);
1518 /* if there's an ep0 reader, don't stall */
1519 if (dev->usermode_setup) {
1520 dev->setup_can_stall = 1;
1522 dev->setup_in = (ctrl->bRequestType & USB_DIR_IN)
1524 dev->setup_wLength = w_length;
1525 dev->setup_out_ready = 0;
1526 dev->setup_out_error = 0;
1529 /* read DATA stage for OUT right away */
1530 if (unlikely (!dev->setup_in && w_length)) {
1531 value = setup_req (gadget->ep0, dev->req,
1535 value = usb_ep_queue (gadget->ep0, dev->req,
1538 clean_req (gadget->ep0, dev->req);
1542 /* we can't currently stall these */
1543 dev->setup_can_stall = 0;
1546 /* state changes when reader collects event */
1547 event = next_event (dev, GADGETFS_SETUP);
1548 event->u.setup = *ctrl;
1550 spin_unlock (&dev->lock);
1555 /* proceed with data transfer and status phases? */
1556 if (value >= 0 && dev->state != STATE_SETUP) {
1557 req->length = value;
1558 req->zero = value < w_length;
1559 value = usb_ep_queue (gadget->ep0, req, GFP_ATOMIC);
1561 DBG (dev, "ep_queue --> %d\n", value);
1566 /* device stalls when value < 0 */
1567 spin_unlock (&dev->lock);
1571 static void destroy_ep_files (struct dev_data *dev)
1573 struct list_head *entry, *tmp;
1575 DBG (dev, "%s %d\n", __FUNCTION__, dev->state);
1577 /* dev->state must prevent interference */
1579 spin_lock_irq (&dev->lock);
1580 list_for_each_safe (entry, tmp, &dev->epfiles) {
1582 struct inode *parent;
1583 struct dentry *dentry;
1585 /* break link to FS */
1586 ep = list_entry (entry, struct ep_data, epfiles);
1587 list_del_init (&ep->epfiles);
1588 dentry = ep->dentry;
1590 parent = dentry->d_parent->d_inode;
1592 /* break link to controller */
1593 if (ep->state == STATE_EP_ENABLED)
1594 (void) usb_ep_disable (ep->ep);
1595 ep->state = STATE_EP_UNBOUND;
1596 usb_ep_free_request (ep->ep, ep->req);
1598 wake_up (&ep->wait);
1601 spin_unlock_irq (&dev->lock);
1603 /* break link to dcache */
1604 mutex_lock (&parent->i_mutex);
1607 mutex_unlock (&parent->i_mutex);
1609 /* fds may still be open */
1612 spin_unlock_irq (&dev->lock);
1616 static struct inode *
1617 gadgetfs_create_file (struct super_block *sb, char const *name,
1618 void *data, const struct file_operations *fops,
1619 struct dentry **dentry_p);
1621 static int activate_ep_files (struct dev_data *dev)
1624 struct ep_data *data;
1626 gadget_for_each_ep (ep, dev->gadget) {
1628 data = kzalloc(sizeof(*data), GFP_KERNEL);
1631 data->state = STATE_EP_DISABLED;
1632 init_MUTEX (&data->lock);
1633 init_waitqueue_head (&data->wait);
1635 strncpy (data->name, ep->name, sizeof (data->name) - 1);
1636 atomic_set (&data->count, 1);
1641 ep->driver_data = data;
1643 data->req = usb_ep_alloc_request (ep, GFP_KERNEL);
1647 data->inode = gadgetfs_create_file (dev->sb, data->name,
1648 data, &ep_config_operations,
1652 list_add_tail (&data->epfiles, &dev->epfiles);
1657 usb_ep_free_request (ep, data->req);
1662 DBG (dev, "%s enomem\n", __FUNCTION__);
1663 destroy_ep_files (dev);
1668 gadgetfs_unbind (struct usb_gadget *gadget)
1670 struct dev_data *dev = get_gadget_data (gadget);
1672 DBG (dev, "%s\n", __FUNCTION__);
1674 spin_lock_irq (&dev->lock);
1675 dev->state = STATE_DEV_UNBOUND;
1676 spin_unlock_irq (&dev->lock);
1678 destroy_ep_files (dev);
1679 gadget->ep0->driver_data = NULL;
1680 set_gadget_data (gadget, NULL);
1682 /* we've already been disconnected ... no i/o is active */
1684 usb_ep_free_request (gadget->ep0, dev->req);
1685 DBG (dev, "%s done\n", __FUNCTION__);
1689 static struct dev_data *the_device;
1692 gadgetfs_bind (struct usb_gadget *gadget)
1694 struct dev_data *dev = the_device;
1698 if (0 != strcmp (CHIP, gadget->name)) {
1699 printk (KERN_ERR "%s expected %s controller not %s\n",
1700 shortname, CHIP, gadget->name);
1704 set_gadget_data (gadget, dev);
1705 dev->gadget = gadget;
1706 gadget->ep0->driver_data = dev;
1707 dev->dev->bMaxPacketSize0 = gadget->ep0->maxpacket;
1709 /* preallocate control response and buffer */
1710 dev->req = usb_ep_alloc_request (gadget->ep0, GFP_KERNEL);
1713 dev->req->context = NULL;
1714 dev->req->complete = epio_complete;
1716 if (activate_ep_files (dev) < 0)
1719 INFO (dev, "bound to %s driver\n", gadget->name);
1720 dev->state = STATE_UNCONNECTED;
1725 gadgetfs_unbind (gadget);
1730 gadgetfs_disconnect (struct usb_gadget *gadget)
1732 struct dev_data *dev = get_gadget_data (gadget);
1734 spin_lock (&dev->lock);
1735 if (dev->state == STATE_UNCONNECTED) {
1736 DBG (dev, "already unconnected\n");
1739 dev->state = STATE_UNCONNECTED;
1741 INFO (dev, "disconnected\n");
1742 next_event (dev, GADGETFS_DISCONNECT);
1745 spin_unlock (&dev->lock);
1749 gadgetfs_suspend (struct usb_gadget *gadget)
1751 struct dev_data *dev = get_gadget_data (gadget);
1753 INFO (dev, "suspended from state %d\n", dev->state);
1754 spin_lock (&dev->lock);
1755 switch (dev->state) {
1756 case STATE_SETUP: // VERY odd... host died??
1757 case STATE_CONNECTED:
1758 case STATE_UNCONNECTED:
1759 next_event (dev, GADGETFS_SUSPEND);
1765 spin_unlock (&dev->lock);
1768 static struct usb_gadget_driver gadgetfs_driver = {
1769 #ifdef CONFIG_USB_GADGET_DUALSPEED
1770 .speed = USB_SPEED_HIGH,
1772 .speed = USB_SPEED_FULL,
1774 .function = (char *) driver_desc,
1775 .bind = gadgetfs_bind,
1776 .unbind = gadgetfs_unbind,
1777 .setup = gadgetfs_setup,
1778 .disconnect = gadgetfs_disconnect,
1779 .suspend = gadgetfs_suspend,
1782 .name = (char *) shortname,
1786 /*----------------------------------------------------------------------*/
1788 static void gadgetfs_nop(struct usb_gadget *arg) { }
1790 static int gadgetfs_probe (struct usb_gadget *gadget)
1792 CHIP = gadget->name;
1796 static struct usb_gadget_driver probe_driver = {
1797 .speed = USB_SPEED_HIGH,
1798 .bind = gadgetfs_probe,
1799 .unbind = gadgetfs_nop,
1800 .setup = (void *)gadgetfs_nop,
1801 .disconnect = gadgetfs_nop,
1808 /* DEVICE INITIALIZATION
1810 * fd = open ("/dev/gadget/$CHIP", O_RDWR)
1811 * status = write (fd, descriptors, sizeof descriptors)
1813 * That write establishes the device configuration, so the kernel can
1814 * bind to the controller ... guaranteeing it can handle enumeration
1815 * at all necessary speeds. Descriptor order is:
1817 * . message tag (u32, host order) ... for now, must be zero; it
1818 * would change to support features like multi-config devices
1819 * . full/low speed config ... all wTotalLength bytes (with interface,
1820 * class, altsetting, endpoint, and other descriptors)
1821 * . high speed config ... all descriptors, for high speed operation;
1822 * this one's optional except for high-speed hardware
1823 * . device descriptor
1825 * Endpoints are not yet enabled. Drivers may want to immediately
1826 * initialize them, using the /dev/gadget/ep* files that are available
1827 * as soon as the kernel sees the configuration, or they can wait
1828 * until device configuration and interface altsetting changes create
1829 * the need to configure (or unconfigure) them.
1831 * After initialization, the device stays active for as long as that
1832 * $CHIP file is open. Events may then be read from that descriptor,
1833 * such as configuration notifications. More complex drivers will handle
1834 * some control requests in user space.
1837 static int is_valid_config (struct usb_config_descriptor *config)
1839 return config->bDescriptorType == USB_DT_CONFIG
1840 && config->bLength == USB_DT_CONFIG_SIZE
1841 && config->bConfigurationValue != 0
1842 && (config->bmAttributes & USB_CONFIG_ATT_ONE) != 0
1843 && (config->bmAttributes & USB_CONFIG_ATT_WAKEUP) == 0;
1844 /* FIXME if gadget->is_otg, _must_ include an otg descriptor */
1845 /* FIXME check lengths: walk to end */
1849 dev_config (struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
1851 struct dev_data *dev = fd->private_data;
1852 ssize_t value = len, length = len;
1857 if (dev->state != STATE_OPENED)
1860 if (len < (USB_DT_CONFIG_SIZE + USB_DT_DEVICE_SIZE + 4))
1863 /* we might need to change message format someday */
1864 if (copy_from_user (&tag, buf, 4))
1871 kbuf = kmalloc (length, SLAB_KERNEL);
1874 if (copy_from_user (kbuf, buf, length)) {
1879 spin_lock_irq (&dev->lock);
1885 /* full or low speed config */
1886 dev->config = (void *) kbuf;
1887 total = le16_to_cpup (&dev->config->wTotalLength);
1888 if (!is_valid_config (dev->config) || total >= length)
1893 /* optional high speed config */
1894 if (kbuf [1] == USB_DT_CONFIG) {
1895 dev->hs_config = (void *) kbuf;
1896 total = le16_to_cpup (&dev->hs_config->wTotalLength);
1897 if (!is_valid_config (dev->hs_config) || total >= length)
1903 /* could support multiple configs, using another encoding! */
1905 /* device descriptor (tweaked for paranoia) */
1906 if (length != USB_DT_DEVICE_SIZE)
1908 dev->dev = (void *)kbuf;
1909 if (dev->dev->bLength != USB_DT_DEVICE_SIZE
1910 || dev->dev->bDescriptorType != USB_DT_DEVICE
1911 || dev->dev->bNumConfigurations != 1)
1913 dev->dev->bNumConfigurations = 1;
1914 dev->dev->bcdUSB = __constant_cpu_to_le16 (0x0200);
1916 /* triggers gadgetfs_bind(); then we can enumerate. */
1917 spin_unlock_irq (&dev->lock);
1918 value = usb_gadget_register_driver (&gadgetfs_driver);
1923 /* at this point "good" hardware has for the first time
1924 * let the USB the host see us. alternatively, if users
1925 * unplug/replug that will clear all the error state.
1927 * note: everything running before here was guaranteed
1928 * to choke driver model style diagnostics. from here
1929 * on, they can work ... except in cleanup paths that
1930 * kick in after the ep0 descriptor is closed.
1932 fd->f_op = &ep0_io_operations;
1938 spin_unlock_irq (&dev->lock);
1939 pr_debug ("%s: %s fail %Zd, %p\n", shortname, __FUNCTION__, value, dev);
1946 dev_open (struct inode *inode, struct file *fd)
1948 struct dev_data *dev = inode->i_private;
1951 if (dev->state == STATE_DEV_DISABLED) {
1953 dev->state = STATE_OPENED;
1954 fd->private_data = dev;
1961 static const struct file_operations dev_init_operations = {
1962 .owner = THIS_MODULE,
1963 .llseek = no_llseek,
1966 .write = dev_config,
1967 .fasync = ep0_fasync,
1969 .release = dev_release,
1972 /*----------------------------------------------------------------------*/
1974 /* FILESYSTEM AND SUPERBLOCK OPERATIONS
1976 * Mounting the filesystem creates a controller file, used first for
1977 * device configuration then later for event monitoring.
1981 /* FIXME PAM etc could set this security policy without mount options
1982 * if epfiles inherited ownership and permissons from ep0 ...
1985 static unsigned default_uid;
1986 static unsigned default_gid;
1987 static unsigned default_perm = S_IRUSR | S_IWUSR;
1989 module_param (default_uid, uint, 0644);
1990 module_param (default_gid, uint, 0644);
1991 module_param (default_perm, uint, 0644);
1994 static struct inode *
1995 gadgetfs_make_inode (struct super_block *sb,
1996 void *data, const struct file_operations *fops,
1999 struct inode *inode = new_inode (sb);
2002 inode->i_mode = mode;
2003 inode->i_uid = default_uid;
2004 inode->i_gid = default_gid;
2005 inode->i_blocks = 0;
2006 inode->i_atime = inode->i_mtime = inode->i_ctime
2008 inode->i_private = data;
2009 inode->i_fop = fops;
2014 /* creates in fs root directory, so non-renamable and non-linkable.
2015 * so inode and dentry are paired, until device reconfig.
2017 static struct inode *
2018 gadgetfs_create_file (struct super_block *sb, char const *name,
2019 void *data, const struct file_operations *fops,
2020 struct dentry **dentry_p)
2022 struct dentry *dentry;
2023 struct inode *inode;
2025 dentry = d_alloc_name(sb->s_root, name);
2029 inode = gadgetfs_make_inode (sb, data, fops,
2030 S_IFREG | (default_perm & S_IRWXUGO));
2035 d_add (dentry, inode);
2040 static struct super_operations gadget_fs_operations = {
2041 .statfs = simple_statfs,
2042 .drop_inode = generic_delete_inode,
2046 gadgetfs_fill_super (struct super_block *sb, void *opts, int silent)
2048 struct inode *inode;
2050 struct dev_data *dev;
2055 /* fake probe to determine $CHIP */
2056 (void) usb_gadget_register_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 (!(d = d_alloc_root (inode)))
2078 /* the ep0 file is named after the controller we expect;
2079 * user mode code can use it for sanity checks, like we do.
2086 if (!gadgetfs_create_file (sb, CHIP,
2087 dev, &dev_init_operations,
2091 /* other endpoint files are available after hardware setup,
2092 * from binding to a controller.
2107 /* "mount -t gadgetfs path /dev/gadget" ends up here */
2109 gadgetfs_get_sb (struct file_system_type *t, int flags,
2110 const char *path, void *opts, struct vfsmount *mnt)
2112 return get_sb_single (t, flags, opts, gadgetfs_fill_super, mnt);
2116 gadgetfs_kill_sb (struct super_block *sb)
2118 kill_litter_super (sb);
2120 put_dev (the_device);
2125 /*----------------------------------------------------------------------*/
2127 static struct file_system_type gadgetfs_type = {
2128 .owner = THIS_MODULE,
2130 .get_sb = gadgetfs_get_sb,
2131 .kill_sb = gadgetfs_kill_sb,
2134 /*----------------------------------------------------------------------*/
2136 static int __init init (void)
2140 status = register_filesystem (&gadgetfs_type);
2142 pr_info ("%s: %s, version " DRIVER_VERSION "\n",
2143 shortname, driver_desc);
2148 static void __exit cleanup (void)
2150 pr_debug ("unregister %s\n", shortname);
2151 unregister_filesystem (&gadgetfs_type);
2153 module_exit (cleanup);