2 * inode.c -- user mode filesystem api for usb gadget controllers
4 * Copyright (C) 2003-2004 David Brownell
5 * Copyright (C) 2003 Agilent Technologies
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 2 of the License, or
10 * (at your option) any later version.
14 /* #define VERBOSE_DEBUG */
16 #include <linux/init.h>
17 #include <linux/module.h>
19 #include <linux/pagemap.h>
20 #include <linux/uts.h>
21 #include <linux/wait.h>
22 #include <linux/compiler.h>
23 #include <asm/uaccess.h>
24 #include <linux/sched.h>
25 #include <linux/slab.h>
26 #include <linux/poll.h>
27 #include <linux/mmu_context.h>
28 #include <linux/aio.h>
30 #include <linux/device.h>
31 #include <linux/moduleparam.h>
33 #include <linux/usb/gadgetfs.h>
34 #include <linux/usb/gadget.h>
38 * The gadgetfs API maps each endpoint to a file descriptor so that you
39 * can use standard synchronous read/write calls for I/O. There's some
40 * O_NONBLOCK and O_ASYNC/FASYNC style i/o support. Example usermode
41 * drivers show how this works in practice. You can also use AIO to
42 * eliminate I/O gaps between requests, to help when streaming data.
44 * Key parts that must be USB-specific are protocols defining how the
45 * read/write operations relate to the hardware state machines. There
46 * are two types of files. One type is for the device, implementing ep0.
47 * The other type is for each IN or OUT endpoint. In both cases, the
48 * user mode driver must configure the hardware before using it.
50 * - First, dev_config() is called when /dev/gadget/$CHIP is configured
51 * (by writing configuration and device descriptors). Afterwards it
52 * may serve as a source of device events, used to handle all control
53 * requests other than basic enumeration.
55 * - Then, after a SET_CONFIGURATION control request, ep_config() is
56 * called when each /dev/gadget/ep* file is configured (by writing
57 * endpoint descriptors). Afterwards these files are used to write()
58 * IN data or to read() OUT data. To halt the endpoint, a "wrong
59 * direction" request is issued (like reading an IN endpoint).
61 * Unlike "usbfs" the only ioctl()s are for things that are rare, and maybe
62 * not possible on all hardware. For example, precise fault handling with
63 * respect to data left in endpoint fifos after aborted operations; or
64 * selective clearing of endpoint halts, to implement SET_INTERFACE.
67 #define DRIVER_DESC "USB Gadget filesystem"
68 #define DRIVER_VERSION "24 Aug 2004"
70 static const char driver_desc
[] = DRIVER_DESC
;
71 static const char shortname
[] = "gadgetfs";
73 MODULE_DESCRIPTION (DRIVER_DESC
);
74 MODULE_AUTHOR ("David Brownell");
75 MODULE_LICENSE ("GPL");
78 /*----------------------------------------------------------------------*/
80 #define GADGETFS_MAGIC 0xaee71ee7
82 /* /dev/gadget/$CHIP represents ep0 and the whole device */
84 /* DISBLED is the initial state.
86 STATE_DEV_DISABLED
= 0,
88 /* Only one open() of /dev/gadget/$CHIP; only one file tracks
89 * ep0/device i/o modes and binding to the controller. Driver
90 * must always write descriptors to initialize the device, then
91 * the device becomes UNCONNECTED until enumeration.
95 /* From then on, ep0 fd is in either of two basic modes:
96 * - (UN)CONNECTED: read usb_gadgetfs_event(s) from it
97 * - SETUP: read/write will transfer control data and succeed;
98 * or if "wrong direction", performs protocol stall
100 STATE_DEV_UNCONNECTED
,
104 /* UNBOUND means the driver closed ep0, so the device won't be
105 * accessible again (DEV_DISABLED) until all fds are closed.
110 /* enough for the whole queue: most events invalidate others */
116 enum ep0_state state
; /* P: lock */
117 struct usb_gadgetfs_event event
[N_EVENT
];
119 struct fasync_struct
*fasync
;
122 /* drivers reading ep0 MUST handle control requests (SETUP)
123 * reported that way; else the host will time out.
125 unsigned usermode_setup
: 1,
131 unsigned setup_wLength
;
133 /* the rest is basically write-once */
134 struct usb_config_descriptor
*config
, *hs_config
;
135 struct usb_device_descriptor
*dev
;
136 struct usb_request
*req
;
137 struct usb_gadget
*gadget
;
138 struct list_head epfiles
;
140 wait_queue_head_t wait
;
141 struct super_block
*sb
;
142 struct dentry
*dentry
;
144 /* except this scratch i/o buffer for ep0 */
148 static inline void get_dev (struct dev_data
*data
)
150 atomic_inc (&data
->count
);
153 static void put_dev (struct dev_data
*data
)
155 if (likely (!atomic_dec_and_test (&data
->count
)))
157 /* needs no more cleanup */
158 BUG_ON (waitqueue_active (&data
->wait
));
162 static struct dev_data
*dev_new (void)
164 struct dev_data
*dev
;
166 dev
= kzalloc(sizeof(*dev
), GFP_KERNEL
);
169 dev
->state
= STATE_DEV_DISABLED
;
170 atomic_set (&dev
->count
, 1);
171 spin_lock_init (&dev
->lock
);
172 INIT_LIST_HEAD (&dev
->epfiles
);
173 init_waitqueue_head (&dev
->wait
);
177 /*----------------------------------------------------------------------*/
179 /* other /dev/gadget/$ENDPOINT files represent endpoints */
181 STATE_EP_DISABLED
= 0,
191 struct dev_data
*dev
;
192 /* must hold dev->lock before accessing ep or req */
194 struct usb_request
*req
;
197 struct usb_endpoint_descriptor desc
, hs_desc
;
198 struct list_head epfiles
;
199 wait_queue_head_t wait
;
200 struct dentry
*dentry
;
204 static inline void get_ep (struct ep_data
*data
)
206 atomic_inc (&data
->count
);
209 static void put_ep (struct ep_data
*data
)
211 if (likely (!atomic_dec_and_test (&data
->count
)))
214 /* needs no more cleanup */
215 BUG_ON (!list_empty (&data
->epfiles
));
216 BUG_ON (waitqueue_active (&data
->wait
));
220 /*----------------------------------------------------------------------*/
222 /* most "how to use the hardware" policy choices are in userspace:
223 * mapping endpoint roles (which the driver needs) to the capabilities
224 * which the usb controller has. most of those capabilities are exposed
225 * implicitly, starting with the driver name and then endpoint names.
228 static const char *CHIP
;
230 /*----------------------------------------------------------------------*/
232 /* NOTE: don't use dev_printk calls before binding to the gadget
233 * at the end of ep0 configuration, or after unbind.
236 /* too wordy: dev_printk(level , &(d)->gadget->dev , fmt , ## args) */
237 #define xprintk(d,level,fmt,args...) \
238 printk(level "%s: " fmt , shortname , ## args)
241 #define DBG(dev,fmt,args...) \
242 xprintk(dev , KERN_DEBUG , fmt , ## args)
244 #define DBG(dev,fmt,args...) \
251 #define VDEBUG(dev,fmt,args...) \
255 #define ERROR(dev,fmt,args...) \
256 xprintk(dev , KERN_ERR , fmt , ## args)
257 #define INFO(dev,fmt,args...) \
258 xprintk(dev , KERN_INFO , fmt , ## args)
261 /*----------------------------------------------------------------------*/
263 /* SYNCHRONOUS ENDPOINT OPERATIONS (bulk/intr/iso)
265 * After opening, configure non-control endpoints. Then use normal
266 * stream read() and write() requests; and maybe ioctl() to get more
267 * precise FIFO status when recovering from cancellation.
270 static void epio_complete (struct usb_ep
*ep
, struct usb_request
*req
)
272 struct ep_data
*epdata
= ep
->driver_data
;
277 epdata
->status
= req
->status
;
279 epdata
->status
= req
->actual
;
280 complete ((struct completion
*)req
->context
);
283 /* tasklock endpoint, returning when it's connected.
284 * still need dev->lock to use epdata->ep.
287 get_ready_ep (unsigned f_flags
, struct ep_data
*epdata
)
291 if (f_flags
& O_NONBLOCK
) {
292 if (!mutex_trylock(&epdata
->lock
))
294 if (epdata
->state
!= STATE_EP_ENABLED
) {
295 mutex_unlock(&epdata
->lock
);
303 val
= mutex_lock_interruptible(&epdata
->lock
);
307 switch (epdata
->state
) {
308 case STATE_EP_ENABLED
:
310 // case STATE_EP_DISABLED: /* "can't happen" */
311 // case STATE_EP_READY: /* "can't happen" */
312 default: /* error! */
313 pr_debug ("%s: ep %p not available, state %d\n",
314 shortname
, epdata
, epdata
->state
);
316 case STATE_EP_UNBOUND
: /* clean disconnect */
318 mutex_unlock(&epdata
->lock
);
324 ep_io (struct ep_data
*epdata
, void *buf
, unsigned len
)
326 DECLARE_COMPLETION_ONSTACK (done
);
329 spin_lock_irq (&epdata
->dev
->lock
);
330 if (likely (epdata
->ep
!= NULL
)) {
331 struct usb_request
*req
= epdata
->req
;
333 req
->context
= &done
;
334 req
->complete
= epio_complete
;
337 value
= usb_ep_queue (epdata
->ep
, req
, GFP_ATOMIC
);
340 spin_unlock_irq (&epdata
->dev
->lock
);
342 if (likely (value
== 0)) {
343 value
= wait_event_interruptible (done
.wait
, done
.done
);
345 spin_lock_irq (&epdata
->dev
->lock
);
346 if (likely (epdata
->ep
!= NULL
)) {
347 DBG (epdata
->dev
, "%s i/o interrupted\n",
349 usb_ep_dequeue (epdata
->ep
, epdata
->req
);
350 spin_unlock_irq (&epdata
->dev
->lock
);
352 wait_event (done
.wait
, done
.done
);
353 if (epdata
->status
== -ECONNRESET
)
354 epdata
->status
= -EINTR
;
356 spin_unlock_irq (&epdata
->dev
->lock
);
358 DBG (epdata
->dev
, "endpoint gone\n");
359 epdata
->status
= -ENODEV
;
362 return epdata
->status
;
368 /* handle a synchronous OUT bulk/intr/iso transfer */
370 ep_read (struct file
*fd
, char __user
*buf
, size_t len
, loff_t
*ptr
)
372 struct ep_data
*data
= fd
->private_data
;
376 if ((value
= get_ready_ep (fd
->f_flags
, data
)) < 0)
379 /* halt any endpoint by doing a "wrong direction" i/o call */
380 if (usb_endpoint_dir_in(&data
->desc
)) {
381 if (usb_endpoint_xfer_isoc(&data
->desc
)) {
382 mutex_unlock(&data
->lock
);
385 DBG (data
->dev
, "%s halt\n", data
->name
);
386 spin_lock_irq (&data
->dev
->lock
);
387 if (likely (data
->ep
!= NULL
))
388 usb_ep_set_halt (data
->ep
);
389 spin_unlock_irq (&data
->dev
->lock
);
390 mutex_unlock(&data
->lock
);
394 /* FIXME readahead for O_NONBLOCK and poll(); careful with ZLPs */
397 kbuf
= kmalloc (len
, GFP_KERNEL
);
398 if (unlikely (!kbuf
))
401 value
= ep_io (data
, kbuf
, len
);
402 VDEBUG (data
->dev
, "%s read %zu OUT, status %d\n",
403 data
->name
, len
, (int) value
);
404 if (value
>= 0 && copy_to_user (buf
, kbuf
, value
))
408 mutex_unlock(&data
->lock
);
413 /* handle a synchronous IN bulk/intr/iso transfer */
415 ep_write (struct file
*fd
, const char __user
*buf
, size_t len
, loff_t
*ptr
)
417 struct ep_data
*data
= fd
->private_data
;
421 if ((value
= get_ready_ep (fd
->f_flags
, data
)) < 0)
424 /* halt any endpoint by doing a "wrong direction" i/o call */
425 if (!usb_endpoint_dir_in(&data
->desc
)) {
426 if (usb_endpoint_xfer_isoc(&data
->desc
)) {
427 mutex_unlock(&data
->lock
);
430 DBG (data
->dev
, "%s halt\n", data
->name
);
431 spin_lock_irq (&data
->dev
->lock
);
432 if (likely (data
->ep
!= NULL
))
433 usb_ep_set_halt (data
->ep
);
434 spin_unlock_irq (&data
->dev
->lock
);
435 mutex_unlock(&data
->lock
);
439 /* FIXME writebehind for O_NONBLOCK and poll(), qlen = 1 */
442 kbuf
= kmalloc (len
, GFP_KERNEL
);
445 if (copy_from_user (kbuf
, buf
, len
)) {
450 value
= ep_io (data
, kbuf
, len
);
451 VDEBUG (data
->dev
, "%s write %zu IN, status %d\n",
452 data
->name
, len
, (int) value
);
454 mutex_unlock(&data
->lock
);
460 ep_release (struct inode
*inode
, struct file
*fd
)
462 struct ep_data
*data
= fd
->private_data
;
465 value
= mutex_lock_interruptible(&data
->lock
);
469 /* clean up if this can be reopened */
470 if (data
->state
!= STATE_EP_UNBOUND
) {
471 data
->state
= STATE_EP_DISABLED
;
472 data
->desc
.bDescriptorType
= 0;
473 data
->hs_desc
.bDescriptorType
= 0;
474 usb_ep_disable(data
->ep
);
476 mutex_unlock(&data
->lock
);
481 static long ep_ioctl(struct file
*fd
, unsigned code
, unsigned long value
)
483 struct ep_data
*data
= fd
->private_data
;
486 if ((status
= get_ready_ep (fd
->f_flags
, data
)) < 0)
489 spin_lock_irq (&data
->dev
->lock
);
490 if (likely (data
->ep
!= NULL
)) {
492 case GADGETFS_FIFO_STATUS
:
493 status
= usb_ep_fifo_status (data
->ep
);
495 case GADGETFS_FIFO_FLUSH
:
496 usb_ep_fifo_flush (data
->ep
);
498 case GADGETFS_CLEAR_HALT
:
499 status
= usb_ep_clear_halt (data
->ep
);
506 spin_unlock_irq (&data
->dev
->lock
);
507 mutex_unlock(&data
->lock
);
511 /*----------------------------------------------------------------------*/
513 /* ASYNCHRONOUS ENDPOINT I/O OPERATIONS (bulk/intr/iso) */
516 struct usb_request
*req
;
517 struct ep_data
*epdata
;
519 struct mm_struct
*mm
;
520 struct work_struct work
;
522 const struct iovec
*iv
;
523 unsigned long nr_segs
;
527 static int ep_aio_cancel(struct kiocb
*iocb
, struct io_event
*e
)
529 struct kiocb_priv
*priv
= iocb
->private;
530 struct ep_data
*epdata
;
534 epdata
= priv
->epdata
;
535 // spin_lock(&epdata->dev->lock);
536 if (likely(epdata
&& epdata
->ep
&& priv
->req
))
537 value
= usb_ep_dequeue (epdata
->ep
, priv
->req
);
540 // spin_unlock(&epdata->dev->lock);
547 static ssize_t
ep_copy_to_user(struct kiocb_priv
*priv
)
553 /* copy stuff into user buffers */
554 total
= priv
->actual
;
557 for (i
=0; i
< priv
->nr_segs
; i
++) {
558 ssize_t
this = min((ssize_t
)(priv
->iv
[i
].iov_len
), total
);
560 if (copy_to_user(priv
->iv
[i
].iov_base
, to_copy
, this)) {
576 static void ep_user_copy_worker(struct work_struct
*work
)
578 struct kiocb_priv
*priv
= container_of(work
, struct kiocb_priv
, work
);
579 struct mm_struct
*mm
= priv
->mm
;
580 struct kiocb
*iocb
= priv
->iocb
;
584 ret
= ep_copy_to_user(priv
);
587 /* completing the iocb can drop the ctx and mm, don't touch mm after */
588 aio_complete(iocb
, ret
, ret
);
594 static void ep_aio_complete(struct usb_ep
*ep
, struct usb_request
*req
)
596 struct kiocb
*iocb
= req
->context
;
597 struct kiocb_priv
*priv
= iocb
->private;
598 struct ep_data
*epdata
= priv
->epdata
;
600 /* lock against disconnect (and ideally, cancel) */
601 spin_lock(&epdata
->dev
->lock
);
605 /* if this was a write or a read returning no data then we
606 * don't need to copy anything to userspace, so we can
607 * complete the aio request immediately.
609 if (priv
->iv
== NULL
|| unlikely(req
->actual
== 0)) {
612 iocb
->private = NULL
;
613 /* aio_complete() reports bytes-transferred _and_ faults */
614 aio_complete(iocb
, req
->actual
? req
->actual
: req
->status
,
617 /* ep_copy_to_user() won't report both; we hide some faults */
618 if (unlikely(0 != req
->status
))
619 DBG(epdata
->dev
, "%s fault %d len %d\n",
620 ep
->name
, req
->status
, req
->actual
);
622 priv
->buf
= req
->buf
;
623 priv
->actual
= req
->actual
;
624 schedule_work(&priv
->work
);
626 spin_unlock(&epdata
->dev
->lock
);
628 usb_ep_free_request(ep
, req
);
637 struct ep_data
*epdata
,
638 const struct iovec
*iv
,
639 unsigned long nr_segs
642 struct kiocb_priv
*priv
;
643 struct usb_request
*req
;
646 priv
= kmalloc(sizeof *priv
, GFP_KERNEL
);
653 iocb
->private = priv
;
656 priv
->nr_segs
= nr_segs
;
657 INIT_WORK(&priv
->work
, ep_user_copy_worker
);
659 value
= get_ready_ep(iocb
->ki_filp
->f_flags
, epdata
);
660 if (unlikely(value
< 0)) {
665 kiocb_set_cancel_fn(iocb
, ep_aio_cancel
);
667 priv
->epdata
= epdata
;
669 priv
->mm
= current
->mm
; /* mm teardown waits for iocbs in exit_aio() */
671 /* each kiocb is coupled to one usb_request, but we can't
672 * allocate or submit those if the host disconnected.
674 spin_lock_irq(&epdata
->dev
->lock
);
675 if (likely(epdata
->ep
)) {
676 req
= usb_ep_alloc_request(epdata
->ep
, GFP_ATOMIC
);
681 req
->complete
= ep_aio_complete
;
683 value
= usb_ep_queue(epdata
->ep
, req
, GFP_ATOMIC
);
684 if (unlikely(0 != value
))
685 usb_ep_free_request(epdata
->ep
, req
);
690 spin_unlock_irq(&epdata
->dev
->lock
);
692 mutex_unlock(&epdata
->lock
);
694 if (unlikely(value
)) {
698 value
= -EIOCBQUEUED
;
703 ep_aio_read(struct kiocb
*iocb
, const struct iovec
*iov
,
704 unsigned long nr_segs
, loff_t o
)
706 struct ep_data
*epdata
= iocb
->ki_filp
->private_data
;
709 if (unlikely(usb_endpoint_dir_in(&epdata
->desc
)))
712 buf
= kmalloc(iocb
->ki_left
, GFP_KERNEL
);
716 return ep_aio_rwtail(iocb
, buf
, iocb
->ki_left
, epdata
, iov
, nr_segs
);
720 ep_aio_write(struct kiocb
*iocb
, const struct iovec
*iov
,
721 unsigned long nr_segs
, loff_t o
)
723 struct ep_data
*epdata
= iocb
->ki_filp
->private_data
;
728 if (unlikely(!usb_endpoint_dir_in(&epdata
->desc
)))
731 buf
= kmalloc(iocb
->ki_left
, GFP_KERNEL
);
735 for (i
=0; i
< nr_segs
; i
++) {
736 if (unlikely(copy_from_user(&buf
[len
], iov
[i
].iov_base
,
737 iov
[i
].iov_len
) != 0)) {
741 len
+= iov
[i
].iov_len
;
743 return ep_aio_rwtail(iocb
, buf
, len
, epdata
, NULL
, 0);
746 /*----------------------------------------------------------------------*/
748 /* used after endpoint configuration */
749 static const struct file_operations ep_io_operations
= {
750 .owner
= THIS_MODULE
,
755 .unlocked_ioctl
= ep_ioctl
,
756 .release
= ep_release
,
758 .aio_read
= ep_aio_read
,
759 .aio_write
= ep_aio_write
,
762 /* ENDPOINT INITIALIZATION
764 * fd = open ("/dev/gadget/$ENDPOINT", O_RDWR)
765 * status = write (fd, descriptors, sizeof descriptors)
767 * That write establishes the endpoint configuration, configuring
768 * the controller to process bulk, interrupt, or isochronous transfers
769 * at the right maxpacket size, and so on.
771 * The descriptors are message type 1, identified by a host order u32
772 * at the beginning of what's written. Descriptor order is: full/low
773 * speed descriptor, then optional high speed descriptor.
776 ep_config (struct file
*fd
, const char __user
*buf
, size_t len
, loff_t
*ptr
)
778 struct ep_data
*data
= fd
->private_data
;
781 int value
, length
= len
;
783 value
= mutex_lock_interruptible(&data
->lock
);
787 if (data
->state
!= STATE_EP_READY
) {
793 if (len
< USB_DT_ENDPOINT_SIZE
+ 4)
796 /* we might need to change message format someday */
797 if (copy_from_user (&tag
, buf
, 4)) {
801 DBG(data
->dev
, "config %s, bad tag %d\n", data
->name
, tag
);
807 /* NOTE: audio endpoint extensions not accepted here;
808 * just don't include the extra bytes.
811 /* full/low speed descriptor, then high speed */
812 if (copy_from_user (&data
->desc
, buf
, USB_DT_ENDPOINT_SIZE
)) {
815 if (data
->desc
.bLength
!= USB_DT_ENDPOINT_SIZE
816 || data
->desc
.bDescriptorType
!= USB_DT_ENDPOINT
)
818 if (len
!= USB_DT_ENDPOINT_SIZE
) {
819 if (len
!= 2 * USB_DT_ENDPOINT_SIZE
)
821 if (copy_from_user (&data
->hs_desc
, buf
+ USB_DT_ENDPOINT_SIZE
,
822 USB_DT_ENDPOINT_SIZE
)) {
825 if (data
->hs_desc
.bLength
!= USB_DT_ENDPOINT_SIZE
826 || data
->hs_desc
.bDescriptorType
827 != USB_DT_ENDPOINT
) {
828 DBG(data
->dev
, "config %s, bad hs length or type\n",
834 spin_lock_irq (&data
->dev
->lock
);
835 if (data
->dev
->state
== STATE_DEV_UNBOUND
) {
838 } else if ((ep
= data
->ep
) == NULL
) {
842 switch (data
->dev
->gadget
->speed
) {
845 ep
->desc
= &data
->desc
;
846 value
= usb_ep_enable(ep
);
848 data
->state
= STATE_EP_ENABLED
;
851 /* fails if caller didn't provide that descriptor... */
852 ep
->desc
= &data
->hs_desc
;
853 value
= usb_ep_enable(ep
);
855 data
->state
= STATE_EP_ENABLED
;
858 DBG(data
->dev
, "unconnected, %s init abandoned\n",
863 fd
->f_op
= &ep_io_operations
;
867 spin_unlock_irq (&data
->dev
->lock
);
870 data
->desc
.bDescriptorType
= 0;
871 data
->hs_desc
.bDescriptorType
= 0;
873 mutex_unlock(&data
->lock
);
884 ep_open (struct inode
*inode
, struct file
*fd
)
886 struct ep_data
*data
= inode
->i_private
;
889 if (mutex_lock_interruptible(&data
->lock
) != 0)
891 spin_lock_irq (&data
->dev
->lock
);
892 if (data
->dev
->state
== STATE_DEV_UNBOUND
)
894 else if (data
->state
== STATE_EP_DISABLED
) {
896 data
->state
= STATE_EP_READY
;
898 fd
->private_data
= data
;
899 VDEBUG (data
->dev
, "%s ready\n", data
->name
);
901 DBG (data
->dev
, "%s state %d\n",
902 data
->name
, data
->state
);
903 spin_unlock_irq (&data
->dev
->lock
);
904 mutex_unlock(&data
->lock
);
908 /* used before endpoint configuration */
909 static const struct file_operations ep_config_operations
= {
914 .release
= ep_release
,
917 /*----------------------------------------------------------------------*/
919 /* EP0 IMPLEMENTATION can be partly in userspace.
921 * Drivers that use this facility receive various events, including
922 * control requests the kernel doesn't handle. Drivers that don't
923 * use this facility may be too simple-minded for real applications.
926 static inline void ep0_readable (struct dev_data
*dev
)
928 wake_up (&dev
->wait
);
929 kill_fasync (&dev
->fasync
, SIGIO
, POLL_IN
);
932 static void clean_req (struct usb_ep
*ep
, struct usb_request
*req
)
934 struct dev_data
*dev
= ep
->driver_data
;
936 if (req
->buf
!= dev
->rbuf
) {
938 req
->buf
= dev
->rbuf
;
940 req
->complete
= epio_complete
;
941 dev
->setup_out_ready
= 0;
944 static void ep0_complete (struct usb_ep
*ep
, struct usb_request
*req
)
946 struct dev_data
*dev
= ep
->driver_data
;
950 /* for control OUT, data must still get to userspace */
951 spin_lock_irqsave(&dev
->lock
, flags
);
952 if (!dev
->setup_in
) {
953 dev
->setup_out_error
= (req
->status
!= 0);
954 if (!dev
->setup_out_error
)
956 dev
->setup_out_ready
= 1;
960 /* clean up as appropriate */
961 if (free
&& req
->buf
!= &dev
->rbuf
)
963 req
->complete
= epio_complete
;
964 spin_unlock_irqrestore(&dev
->lock
, flags
);
967 static int setup_req (struct usb_ep
*ep
, struct usb_request
*req
, u16 len
)
969 struct dev_data
*dev
= ep
->driver_data
;
971 if (dev
->setup_out_ready
) {
972 DBG (dev
, "ep0 request busy!\n");
975 if (len
> sizeof (dev
->rbuf
))
976 req
->buf
= kmalloc(len
, GFP_ATOMIC
);
977 if (req
->buf
== NULL
) {
978 req
->buf
= dev
->rbuf
;
981 req
->complete
= ep0_complete
;
988 ep0_read (struct file
*fd
, char __user
*buf
, size_t len
, loff_t
*ptr
)
990 struct dev_data
*dev
= fd
->private_data
;
992 enum ep0_state state
;
994 spin_lock_irq (&dev
->lock
);
996 /* report fd mode change before acting on it */
997 if (dev
->setup_abort
) {
998 dev
->setup_abort
= 0;
1003 /* control DATA stage */
1004 if ((state
= dev
->state
) == STATE_DEV_SETUP
) {
1006 if (dev
->setup_in
) { /* stall IN */
1007 VDEBUG(dev
, "ep0in stall\n");
1008 (void) usb_ep_set_halt (dev
->gadget
->ep0
);
1010 dev
->state
= STATE_DEV_CONNECTED
;
1012 } else if (len
== 0) { /* ack SET_CONFIGURATION etc */
1013 struct usb_ep
*ep
= dev
->gadget
->ep0
;
1014 struct usb_request
*req
= dev
->req
;
1016 if ((retval
= setup_req (ep
, req
, 0)) == 0)
1017 retval
= usb_ep_queue (ep
, req
, GFP_ATOMIC
);
1018 dev
->state
= STATE_DEV_CONNECTED
;
1020 /* assume that was SET_CONFIGURATION */
1021 if (dev
->current_config
) {
1024 if (gadget_is_dualspeed(dev
->gadget
)
1025 && (dev
->gadget
->speed
1027 power
= dev
->hs_config
->bMaxPower
;
1029 power
= dev
->config
->bMaxPower
;
1030 usb_gadget_vbus_draw(dev
->gadget
, 2 * power
);
1033 } else { /* collect OUT data */
1034 if ((fd
->f_flags
& O_NONBLOCK
) != 0
1035 && !dev
->setup_out_ready
) {
1039 spin_unlock_irq (&dev
->lock
);
1040 retval
= wait_event_interruptible (dev
->wait
,
1041 dev
->setup_out_ready
!= 0);
1043 /* FIXME state could change from under us */
1044 spin_lock_irq (&dev
->lock
);
1048 if (dev
->state
!= STATE_DEV_SETUP
) {
1049 retval
= -ECANCELED
;
1052 dev
->state
= STATE_DEV_CONNECTED
;
1054 if (dev
->setup_out_error
)
1057 len
= min (len
, (size_t)dev
->req
->actual
);
1058 // FIXME don't call this with the spinlock held ...
1059 if (copy_to_user (buf
, dev
->req
->buf
, len
))
1063 clean_req (dev
->gadget
->ep0
, dev
->req
);
1064 /* NOTE userspace can't yet choose to stall */
1070 /* else normal: return event data */
1071 if (len
< sizeof dev
->event
[0]) {
1075 len
-= len
% sizeof (struct usb_gadgetfs_event
);
1076 dev
->usermode_setup
= 1;
1079 /* return queued events right away */
1080 if (dev
->ev_next
!= 0) {
1083 n
= len
/ sizeof (struct usb_gadgetfs_event
);
1084 if (dev
->ev_next
< n
)
1087 /* ep0 i/o has special semantics during STATE_DEV_SETUP */
1088 for (i
= 0; i
< n
; i
++) {
1089 if (dev
->event
[i
].type
== GADGETFS_SETUP
) {
1090 dev
->state
= STATE_DEV_SETUP
;
1095 spin_unlock_irq (&dev
->lock
);
1096 len
= n
* sizeof (struct usb_gadgetfs_event
);
1097 if (copy_to_user (buf
, &dev
->event
, len
))
1102 /* NOTE this doesn't guard against broken drivers;
1103 * concurrent ep0 readers may lose events.
1105 spin_lock_irq (&dev
->lock
);
1106 if (dev
->ev_next
> n
) {
1107 memmove(&dev
->event
[0], &dev
->event
[n
],
1108 sizeof (struct usb_gadgetfs_event
)
1109 * (dev
->ev_next
- n
));
1112 spin_unlock_irq (&dev
->lock
);
1116 if (fd
->f_flags
& O_NONBLOCK
) {
1123 DBG (dev
, "fail %s, state %d\n", __func__
, state
);
1126 case STATE_DEV_UNCONNECTED
:
1127 case STATE_DEV_CONNECTED
:
1128 spin_unlock_irq (&dev
->lock
);
1129 DBG (dev
, "%s wait\n", __func__
);
1131 /* wait for events */
1132 retval
= wait_event_interruptible (dev
->wait
,
1136 spin_lock_irq (&dev
->lock
);
1141 spin_unlock_irq (&dev
->lock
);
1145 static struct usb_gadgetfs_event
*
1146 next_event (struct dev_data
*dev
, enum usb_gadgetfs_event_type type
)
1148 struct usb_gadgetfs_event
*event
;
1152 /* these events purge the queue */
1153 case GADGETFS_DISCONNECT
:
1154 if (dev
->state
== STATE_DEV_SETUP
)
1155 dev
->setup_abort
= 1;
1157 case GADGETFS_CONNECT
:
1160 case GADGETFS_SETUP
: /* previous request timed out */
1161 case GADGETFS_SUSPEND
: /* same effect */
1162 /* these events can't be repeated */
1163 for (i
= 0; i
!= dev
->ev_next
; i
++) {
1164 if (dev
->event
[i
].type
!= type
)
1166 DBG(dev
, "discard old event[%d] %d\n", i
, type
);
1168 if (i
== dev
->ev_next
)
1170 /* indices start at zero, for simplicity */
1171 memmove (&dev
->event
[i
], &dev
->event
[i
+ 1],
1172 sizeof (struct usb_gadgetfs_event
)
1173 * (dev
->ev_next
- i
));
1179 VDEBUG(dev
, "event[%d] = %d\n", dev
->ev_next
, type
);
1180 event
= &dev
->event
[dev
->ev_next
++];
1181 BUG_ON (dev
->ev_next
> N_EVENT
);
1182 memset (event
, 0, sizeof *event
);
1188 ep0_write (struct file
*fd
, const char __user
*buf
, size_t len
, loff_t
*ptr
)
1190 struct dev_data
*dev
= fd
->private_data
;
1191 ssize_t retval
= -ESRCH
;
1193 spin_lock_irq (&dev
->lock
);
1195 /* report fd mode change before acting on it */
1196 if (dev
->setup_abort
) {
1197 dev
->setup_abort
= 0;
1200 /* data and/or status stage for control request */
1201 } else if (dev
->state
== STATE_DEV_SETUP
) {
1203 /* IN DATA+STATUS caller makes len <= wLength */
1204 if (dev
->setup_in
) {
1205 retval
= setup_req (dev
->gadget
->ep0
, dev
->req
, len
);
1207 dev
->state
= STATE_DEV_CONNECTED
;
1208 spin_unlock_irq (&dev
->lock
);
1209 if (copy_from_user (dev
->req
->buf
, buf
, len
))
1212 if (len
< dev
->setup_wLength
)
1214 retval
= usb_ep_queue (
1215 dev
->gadget
->ep0
, dev
->req
,
1219 spin_lock_irq (&dev
->lock
);
1220 clean_req (dev
->gadget
->ep0
, dev
->req
);
1221 spin_unlock_irq (&dev
->lock
);
1228 /* can stall some OUT transfers */
1229 } else if (dev
->setup_can_stall
) {
1230 VDEBUG(dev
, "ep0out stall\n");
1231 (void) usb_ep_set_halt (dev
->gadget
->ep0
);
1233 dev
->state
= STATE_DEV_CONNECTED
;
1235 DBG(dev
, "bogus ep0out stall!\n");
1238 DBG (dev
, "fail %s, state %d\n", __func__
, dev
->state
);
1240 spin_unlock_irq (&dev
->lock
);
1245 ep0_fasync (int f
, struct file
*fd
, int on
)
1247 struct dev_data
*dev
= fd
->private_data
;
1248 // caller must F_SETOWN before signal delivery happens
1249 VDEBUG (dev
, "%s %s\n", __func__
, on
? "on" : "off");
1250 return fasync_helper (f
, fd
, on
, &dev
->fasync
);
1253 static struct usb_gadget_driver gadgetfs_driver
;
1256 dev_release (struct inode
*inode
, struct file
*fd
)
1258 struct dev_data
*dev
= fd
->private_data
;
1260 /* closing ep0 === shutdown all */
1262 usb_gadget_unregister_driver (&gadgetfs_driver
);
1264 /* at this point "good" hardware has disconnected the
1265 * device from USB; the host won't see it any more.
1266 * alternatively, all host requests will time out.
1273 /* other endpoints were all decoupled from this device */
1274 spin_lock_irq(&dev
->lock
);
1275 dev
->state
= STATE_DEV_DISABLED
;
1276 spin_unlock_irq(&dev
->lock
);
1281 ep0_poll (struct file
*fd
, poll_table
*wait
)
1283 struct dev_data
*dev
= fd
->private_data
;
1286 poll_wait(fd
, &dev
->wait
, wait
);
1288 spin_lock_irq (&dev
->lock
);
1290 /* report fd mode change before acting on it */
1291 if (dev
->setup_abort
) {
1292 dev
->setup_abort
= 0;
1297 if (dev
->state
== STATE_DEV_SETUP
) {
1298 if (dev
->setup_in
|| dev
->setup_can_stall
)
1301 if (dev
->ev_next
!= 0)
1305 spin_unlock_irq(&dev
->lock
);
1309 static long dev_ioctl (struct file
*fd
, unsigned code
, unsigned long value
)
1311 struct dev_data
*dev
= fd
->private_data
;
1312 struct usb_gadget
*gadget
= dev
->gadget
;
1315 if (gadget
->ops
->ioctl
)
1316 ret
= gadget
->ops
->ioctl (gadget
, code
, value
);
1321 /* used after device configuration */
1322 static const struct file_operations ep0_io_operations
= {
1323 .owner
= THIS_MODULE
,
1324 .llseek
= no_llseek
,
1328 .fasync
= ep0_fasync
,
1330 .unlocked_ioctl
= dev_ioctl
,
1331 .release
= dev_release
,
1334 /*----------------------------------------------------------------------*/
1336 /* The in-kernel gadget driver handles most ep0 issues, in particular
1337 * enumerating the single configuration (as provided from user space).
1339 * Unrecognized ep0 requests may be handled in user space.
1342 static void make_qualifier (struct dev_data
*dev
)
1344 struct usb_qualifier_descriptor qual
;
1345 struct usb_device_descriptor
*desc
;
1347 qual
.bLength
= sizeof qual
;
1348 qual
.bDescriptorType
= USB_DT_DEVICE_QUALIFIER
;
1349 qual
.bcdUSB
= cpu_to_le16 (0x0200);
1352 qual
.bDeviceClass
= desc
->bDeviceClass
;
1353 qual
.bDeviceSubClass
= desc
->bDeviceSubClass
;
1354 qual
.bDeviceProtocol
= desc
->bDeviceProtocol
;
1356 /* assumes ep0 uses the same value for both speeds ... */
1357 qual
.bMaxPacketSize0
= dev
->gadget
->ep0
->maxpacket
;
1359 qual
.bNumConfigurations
= 1;
1362 memcpy (dev
->rbuf
, &qual
, sizeof qual
);
1366 config_buf (struct dev_data
*dev
, u8 type
, unsigned index
)
1371 /* only one configuration */
1375 if (gadget_is_dualspeed(dev
->gadget
)) {
1376 hs
= (dev
->gadget
->speed
== USB_SPEED_HIGH
);
1377 if (type
== USB_DT_OTHER_SPEED_CONFIG
)
1381 dev
->req
->buf
= dev
->hs_config
;
1382 len
= le16_to_cpu(dev
->hs_config
->wTotalLength
);
1384 dev
->req
->buf
= dev
->config
;
1385 len
= le16_to_cpu(dev
->config
->wTotalLength
);
1387 ((u8
*)dev
->req
->buf
) [1] = type
;
1392 gadgetfs_setup (struct usb_gadget
*gadget
, const struct usb_ctrlrequest
*ctrl
)
1394 struct dev_data
*dev
= get_gadget_data (gadget
);
1395 struct usb_request
*req
= dev
->req
;
1396 int value
= -EOPNOTSUPP
;
1397 struct usb_gadgetfs_event
*event
;
1398 u16 w_value
= le16_to_cpu(ctrl
->wValue
);
1399 u16 w_length
= le16_to_cpu(ctrl
->wLength
);
1401 spin_lock (&dev
->lock
);
1402 dev
->setup_abort
= 0;
1403 if (dev
->state
== STATE_DEV_UNCONNECTED
) {
1404 if (gadget_is_dualspeed(gadget
)
1405 && gadget
->speed
== USB_SPEED_HIGH
1406 && dev
->hs_config
== NULL
) {
1407 spin_unlock(&dev
->lock
);
1408 ERROR (dev
, "no high speed config??\n");
1412 dev
->state
= STATE_DEV_CONNECTED
;
1414 INFO (dev
, "connected\n");
1415 event
= next_event (dev
, GADGETFS_CONNECT
);
1416 event
->u
.speed
= gadget
->speed
;
1419 /* host may have given up waiting for response. we can miss control
1420 * requests handled lower down (device/endpoint status and features);
1421 * then ep0_{read,write} will report the wrong status. controller
1422 * driver will have aborted pending i/o.
1424 } else if (dev
->state
== STATE_DEV_SETUP
)
1425 dev
->setup_abort
= 1;
1427 req
->buf
= dev
->rbuf
;
1428 req
->context
= NULL
;
1429 value
= -EOPNOTSUPP
;
1430 switch (ctrl
->bRequest
) {
1432 case USB_REQ_GET_DESCRIPTOR
:
1433 if (ctrl
->bRequestType
!= USB_DIR_IN
)
1435 switch (w_value
>> 8) {
1438 value
= min (w_length
, (u16
) sizeof *dev
->dev
);
1439 dev
->dev
->bMaxPacketSize0
= dev
->gadget
->ep0
->maxpacket
;
1440 req
->buf
= dev
->dev
;
1442 case USB_DT_DEVICE_QUALIFIER
:
1443 if (!dev
->hs_config
)
1445 value
= min (w_length
, (u16
)
1446 sizeof (struct usb_qualifier_descriptor
));
1447 make_qualifier (dev
);
1449 case USB_DT_OTHER_SPEED_CONFIG
:
1452 value
= config_buf (dev
,
1456 value
= min (w_length
, (u16
) value
);
1461 default: // all others are errors
1466 /* currently one config, two speeds */
1467 case USB_REQ_SET_CONFIGURATION
:
1468 if (ctrl
->bRequestType
!= 0)
1470 if (0 == (u8
) w_value
) {
1472 dev
->current_config
= 0;
1473 usb_gadget_vbus_draw(gadget
, 8 /* mA */ );
1474 // user mode expected to disable endpoints
1478 if (gadget_is_dualspeed(gadget
)
1479 && gadget
->speed
== USB_SPEED_HIGH
) {
1480 config
= dev
->hs_config
->bConfigurationValue
;
1481 power
= dev
->hs_config
->bMaxPower
;
1483 config
= dev
->config
->bConfigurationValue
;
1484 power
= dev
->config
->bMaxPower
;
1487 if (config
== (u8
) w_value
) {
1489 dev
->current_config
= config
;
1490 usb_gadget_vbus_draw(gadget
, 2 * power
);
1494 /* report SET_CONFIGURATION like any other control request,
1495 * except that usermode may not stall this. the next
1496 * request mustn't be allowed start until this finishes:
1497 * endpoints and threads set up, etc.
1499 * NOTE: older PXA hardware (before PXA 255: without UDCCFR)
1500 * has bad/racey automagic that prevents synchronizing here.
1501 * even kernel mode drivers often miss them.
1504 INFO (dev
, "configuration #%d\n", dev
->current_config
);
1505 if (dev
->usermode_setup
) {
1506 dev
->setup_can_stall
= 0;
1512 #ifndef CONFIG_USB_GADGET_PXA25X
1513 /* PXA automagically handles this request too */
1514 case USB_REQ_GET_CONFIGURATION
:
1515 if (ctrl
->bRequestType
!= 0x80)
1517 *(u8
*)req
->buf
= dev
->current_config
;
1518 value
= min (w_length
, (u16
) 1);
1524 VDEBUG (dev
, "%s req%02x.%02x v%04x i%04x l%d\n",
1525 dev
->usermode_setup
? "delegate" : "fail",
1526 ctrl
->bRequestType
, ctrl
->bRequest
,
1527 w_value
, le16_to_cpu(ctrl
->wIndex
), w_length
);
1529 /* if there's an ep0 reader, don't stall */
1530 if (dev
->usermode_setup
) {
1531 dev
->setup_can_stall
= 1;
1533 dev
->setup_in
= (ctrl
->bRequestType
& USB_DIR_IN
)
1535 dev
->setup_wLength
= w_length
;
1536 dev
->setup_out_ready
= 0;
1537 dev
->setup_out_error
= 0;
1540 /* read DATA stage for OUT right away */
1541 if (unlikely (!dev
->setup_in
&& w_length
)) {
1542 value
= setup_req (gadget
->ep0
, dev
->req
,
1546 value
= usb_ep_queue (gadget
->ep0
, dev
->req
,
1549 clean_req (gadget
->ep0
, dev
->req
);
1553 /* we can't currently stall these */
1554 dev
->setup_can_stall
= 0;
1557 /* state changes when reader collects event */
1558 event
= next_event (dev
, GADGETFS_SETUP
);
1559 event
->u
.setup
= *ctrl
;
1561 spin_unlock (&dev
->lock
);
1566 /* proceed with data transfer and status phases? */
1567 if (value
>= 0 && dev
->state
!= STATE_DEV_SETUP
) {
1568 req
->length
= value
;
1569 req
->zero
= value
< w_length
;
1570 value
= usb_ep_queue (gadget
->ep0
, req
, GFP_ATOMIC
);
1572 DBG (dev
, "ep_queue --> %d\n", value
);
1577 /* device stalls when value < 0 */
1578 spin_unlock (&dev
->lock
);
1582 static void destroy_ep_files (struct dev_data
*dev
)
1584 DBG (dev
, "%s %d\n", __func__
, dev
->state
);
1586 /* dev->state must prevent interference */
1587 spin_lock_irq (&dev
->lock
);
1588 while (!list_empty(&dev
->epfiles
)) {
1590 struct inode
*parent
;
1591 struct dentry
*dentry
;
1593 /* break link to FS */
1594 ep
= list_first_entry (&dev
->epfiles
, struct ep_data
, epfiles
);
1595 list_del_init (&ep
->epfiles
);
1596 dentry
= ep
->dentry
;
1598 parent
= dentry
->d_parent
->d_inode
;
1600 /* break link to controller */
1601 if (ep
->state
== STATE_EP_ENABLED
)
1602 (void) usb_ep_disable (ep
->ep
);
1603 ep
->state
= STATE_EP_UNBOUND
;
1604 usb_ep_free_request (ep
->ep
, ep
->req
);
1606 wake_up (&ep
->wait
);
1609 spin_unlock_irq (&dev
->lock
);
1611 /* break link to dcache */
1612 mutex_lock (&parent
->i_mutex
);
1615 mutex_unlock (&parent
->i_mutex
);
1617 spin_lock_irq (&dev
->lock
);
1619 spin_unlock_irq (&dev
->lock
);
1623 static struct inode
*
1624 gadgetfs_create_file (struct super_block
*sb
, char const *name
,
1625 void *data
, const struct file_operations
*fops
,
1626 struct dentry
**dentry_p
);
1628 static int activate_ep_files (struct dev_data
*dev
)
1631 struct ep_data
*data
;
1633 gadget_for_each_ep (ep
, dev
->gadget
) {
1635 data
= kzalloc(sizeof(*data
), GFP_KERNEL
);
1638 data
->state
= STATE_EP_DISABLED
;
1639 mutex_init(&data
->lock
);
1640 init_waitqueue_head (&data
->wait
);
1642 strncpy (data
->name
, ep
->name
, sizeof (data
->name
) - 1);
1643 atomic_set (&data
->count
, 1);
1648 ep
->driver_data
= data
;
1650 data
->req
= usb_ep_alloc_request (ep
, GFP_KERNEL
);
1654 data
->inode
= gadgetfs_create_file (dev
->sb
, data
->name
,
1655 data
, &ep_config_operations
,
1659 list_add_tail (&data
->epfiles
, &dev
->epfiles
);
1664 usb_ep_free_request (ep
, data
->req
);
1669 DBG (dev
, "%s enomem\n", __func__
);
1670 destroy_ep_files (dev
);
1675 gadgetfs_unbind (struct usb_gadget
*gadget
)
1677 struct dev_data
*dev
= get_gadget_data (gadget
);
1679 DBG (dev
, "%s\n", __func__
);
1681 spin_lock_irq (&dev
->lock
);
1682 dev
->state
= STATE_DEV_UNBOUND
;
1683 spin_unlock_irq (&dev
->lock
);
1685 destroy_ep_files (dev
);
1686 gadget
->ep0
->driver_data
= NULL
;
1687 set_gadget_data (gadget
, NULL
);
1689 /* we've already been disconnected ... no i/o is active */
1691 usb_ep_free_request (gadget
->ep0
, dev
->req
);
1692 DBG (dev
, "%s done\n", __func__
);
1696 static struct dev_data
*the_device
;
1698 static int gadgetfs_bind(struct usb_gadget
*gadget
,
1699 struct usb_gadget_driver
*driver
)
1701 struct dev_data
*dev
= the_device
;
1705 if (0 != strcmp (CHIP
, gadget
->name
)) {
1706 pr_err("%s expected %s controller not %s\n",
1707 shortname
, CHIP
, gadget
->name
);
1711 set_gadget_data (gadget
, dev
);
1712 dev
->gadget
= gadget
;
1713 gadget
->ep0
->driver_data
= dev
;
1715 /* preallocate control response and buffer */
1716 dev
->req
= usb_ep_alloc_request (gadget
->ep0
, GFP_KERNEL
);
1719 dev
->req
->context
= NULL
;
1720 dev
->req
->complete
= epio_complete
;
1722 if (activate_ep_files (dev
) < 0)
1725 INFO (dev
, "bound to %s driver\n", gadget
->name
);
1726 spin_lock_irq(&dev
->lock
);
1727 dev
->state
= STATE_DEV_UNCONNECTED
;
1728 spin_unlock_irq(&dev
->lock
);
1733 gadgetfs_unbind (gadget
);
1738 gadgetfs_disconnect (struct usb_gadget
*gadget
)
1740 struct dev_data
*dev
= get_gadget_data (gadget
);
1741 unsigned long flags
;
1743 spin_lock_irqsave (&dev
->lock
, flags
);
1744 if (dev
->state
== STATE_DEV_UNCONNECTED
)
1746 dev
->state
= STATE_DEV_UNCONNECTED
;
1748 INFO (dev
, "disconnected\n");
1749 next_event (dev
, GADGETFS_DISCONNECT
);
1752 spin_unlock_irqrestore (&dev
->lock
, flags
);
1756 gadgetfs_suspend (struct usb_gadget
*gadget
)
1758 struct dev_data
*dev
= get_gadget_data (gadget
);
1760 INFO (dev
, "suspended from state %d\n", dev
->state
);
1761 spin_lock (&dev
->lock
);
1762 switch (dev
->state
) {
1763 case STATE_DEV_SETUP
: // VERY odd... host died??
1764 case STATE_DEV_CONNECTED
:
1765 case STATE_DEV_UNCONNECTED
:
1766 next_event (dev
, GADGETFS_SUSPEND
);
1772 spin_unlock (&dev
->lock
);
1775 static struct usb_gadget_driver gadgetfs_driver
= {
1776 .function
= (char *) driver_desc
,
1777 .bind
= gadgetfs_bind
,
1778 .unbind
= gadgetfs_unbind
,
1779 .setup
= gadgetfs_setup
,
1780 .disconnect
= gadgetfs_disconnect
,
1781 .suspend
= gadgetfs_suspend
,
1784 .name
= (char *) shortname
,
1788 /*----------------------------------------------------------------------*/
1790 static void gadgetfs_nop(struct usb_gadget
*arg
) { }
1792 static int gadgetfs_probe(struct usb_gadget
*gadget
,
1793 struct usb_gadget_driver
*driver
)
1795 CHIP
= gadget
->name
;
1799 static struct usb_gadget_driver probe_driver
= {
1800 .max_speed
= USB_SPEED_HIGH
,
1801 .bind
= gadgetfs_probe
,
1802 .unbind
= gadgetfs_nop
,
1803 .setup
= (void *)gadgetfs_nop
,
1804 .disconnect
= gadgetfs_nop
,
1811 /* DEVICE INITIALIZATION
1813 * fd = open ("/dev/gadget/$CHIP", O_RDWR)
1814 * status = write (fd, descriptors, sizeof descriptors)
1816 * That write establishes the device configuration, so the kernel can
1817 * bind to the controller ... guaranteeing it can handle enumeration
1818 * at all necessary speeds. Descriptor order is:
1820 * . message tag (u32, host order) ... for now, must be zero; it
1821 * would change to support features like multi-config devices
1822 * . full/low speed config ... all wTotalLength bytes (with interface,
1823 * class, altsetting, endpoint, and other descriptors)
1824 * . high speed config ... all descriptors, for high speed operation;
1825 * this one's optional except for high-speed hardware
1826 * . device descriptor
1828 * Endpoints are not yet enabled. Drivers must wait until device
1829 * configuration and interface altsetting changes create
1830 * the need to configure (or unconfigure) them.
1832 * After initialization, the device stays active for as long as that
1833 * $CHIP file is open. Events must then be read from that descriptor,
1834 * such as configuration notifications.
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 (len
< (USB_DT_CONFIG_SIZE
+ USB_DT_DEVICE_SIZE
+ 4))
1860 /* we might need to change message format someday */
1861 if (copy_from_user (&tag
, buf
, 4))
1868 kbuf
= memdup_user(buf
, length
);
1870 return PTR_ERR(kbuf
);
1872 spin_lock_irq (&dev
->lock
);
1878 /* full or low speed config */
1879 dev
->config
= (void *) kbuf
;
1880 total
= le16_to_cpu(dev
->config
->wTotalLength
);
1881 if (!is_valid_config (dev
->config
) || total
>= length
)
1886 /* optional high speed config */
1887 if (kbuf
[1] == USB_DT_CONFIG
) {
1888 dev
->hs_config
= (void *) kbuf
;
1889 total
= le16_to_cpu(dev
->hs_config
->wTotalLength
);
1890 if (!is_valid_config (dev
->hs_config
) || total
>= length
)
1896 /* could support multiple configs, using another encoding! */
1898 /* device descriptor (tweaked for paranoia) */
1899 if (length
!= USB_DT_DEVICE_SIZE
)
1901 dev
->dev
= (void *)kbuf
;
1902 if (dev
->dev
->bLength
!= USB_DT_DEVICE_SIZE
1903 || dev
->dev
->bDescriptorType
!= USB_DT_DEVICE
1904 || dev
->dev
->bNumConfigurations
!= 1)
1906 dev
->dev
->bNumConfigurations
= 1;
1907 dev
->dev
->bcdUSB
= cpu_to_le16 (0x0200);
1909 /* triggers gadgetfs_bind(); then we can enumerate. */
1910 spin_unlock_irq (&dev
->lock
);
1912 gadgetfs_driver
.max_speed
= USB_SPEED_HIGH
;
1914 gadgetfs_driver
.max_speed
= USB_SPEED_FULL
;
1916 value
= usb_gadget_probe_driver(&gadgetfs_driver
);
1921 /* at this point "good" hardware has for the first time
1922 * let the USB the host see us. alternatively, if users
1923 * unplug/replug that will clear all the error state.
1925 * note: everything running before here was guaranteed
1926 * to choke driver model style diagnostics. from here
1927 * on, they can work ... except in cleanup paths that
1928 * kick in after the ep0 descriptor is closed.
1930 fd
->f_op
= &ep0_io_operations
;
1936 spin_unlock_irq (&dev
->lock
);
1937 pr_debug ("%s: %s fail %Zd, %p\n", shortname
, __func__
, value
, dev
);
1944 dev_open (struct inode
*inode
, struct file
*fd
)
1946 struct dev_data
*dev
= inode
->i_private
;
1949 spin_lock_irq(&dev
->lock
);
1950 if (dev
->state
== STATE_DEV_DISABLED
) {
1952 dev
->state
= STATE_DEV_OPENED
;
1953 fd
->private_data
= dev
;
1957 spin_unlock_irq(&dev
->lock
);
1961 static const struct file_operations dev_init_operations
= {
1962 .llseek
= no_llseek
,
1965 .write
= dev_config
,
1966 .fasync
= ep0_fasync
,
1967 .unlocked_ioctl
= dev_ioctl
,
1968 .release
= dev_release
,
1971 /*----------------------------------------------------------------------*/
1973 /* FILESYSTEM AND SUPERBLOCK OPERATIONS
1975 * Mounting the filesystem creates a controller file, used first for
1976 * device configuration then later for event monitoring.
1980 /* FIXME PAM etc could set this security policy without mount options
1981 * if epfiles inherited ownership and permissons from ep0 ...
1984 static unsigned default_uid
;
1985 static unsigned default_gid
;
1986 static unsigned default_perm
= S_IRUSR
| S_IWUSR
;
1988 module_param (default_uid
, uint
, 0644);
1989 module_param (default_gid
, uint
, 0644);
1990 module_param (default_perm
, uint
, 0644);
1993 static struct inode
*
1994 gadgetfs_make_inode (struct super_block
*sb
,
1995 void *data
, const struct file_operations
*fops
,
1998 struct inode
*inode
= new_inode (sb
);
2001 inode
->i_ino
= get_next_ino();
2002 inode
->i_mode
= mode
;
2003 inode
->i_uid
= make_kuid(&init_user_ns
, default_uid
);
2004 inode
->i_gid
= make_kgid(&init_user_ns
, default_gid
);
2005 inode
->i_atime
= inode
->i_mtime
= inode
->i_ctime
2007 inode
->i_private
= data
;
2008 inode
->i_fop
= fops
;
2013 /* creates in fs root directory, so non-renamable and non-linkable.
2014 * so inode and dentry are paired, until device reconfig.
2016 static struct inode
*
2017 gadgetfs_create_file (struct super_block
*sb
, char const *name
,
2018 void *data
, const struct file_operations
*fops
,
2019 struct dentry
**dentry_p
)
2021 struct dentry
*dentry
;
2022 struct inode
*inode
;
2024 dentry
= d_alloc_name(sb
->s_root
, name
);
2028 inode
= gadgetfs_make_inode (sb
, data
, fops
,
2029 S_IFREG
| (default_perm
& S_IRWXUGO
));
2034 d_add (dentry
, inode
);
2039 static const struct super_operations gadget_fs_operations
= {
2040 .statfs
= simple_statfs
,
2041 .drop_inode
= generic_delete_inode
,
2045 gadgetfs_fill_super (struct super_block
*sb
, void *opts
, int silent
)
2047 struct inode
*inode
;
2048 struct dev_data
*dev
;
2053 /* fake probe to determine $CHIP */
2054 usb_gadget_probe_driver(&probe_driver
);
2059 sb
->s_blocksize
= PAGE_CACHE_SIZE
;
2060 sb
->s_blocksize_bits
= PAGE_CACHE_SHIFT
;
2061 sb
->s_magic
= GADGETFS_MAGIC
;
2062 sb
->s_op
= &gadget_fs_operations
;
2063 sb
->s_time_gran
= 1;
2066 inode
= gadgetfs_make_inode (sb
,
2067 NULL
, &simple_dir_operations
,
2068 S_IFDIR
| S_IRUGO
| S_IXUGO
);
2071 inode
->i_op
= &simple_dir_inode_operations
;
2072 if (!(sb
->s_root
= d_make_root (inode
)))
2075 /* the ep0 file is named after the controller we expect;
2076 * user mode code can use it for sanity checks, like we do.
2083 if (!gadgetfs_create_file (sb
, CHIP
,
2084 dev
, &dev_init_operations
,
2090 /* other endpoint files are available after hardware setup,
2091 * from binding to a controller.
2100 /* "mount -t gadgetfs path /dev/gadget" ends up here */
2101 static struct dentry
*
2102 gadgetfs_mount (struct file_system_type
*t
, int flags
,
2103 const char *path
, void *opts
)
2105 return mount_single (t
, flags
, opts
, gadgetfs_fill_super
);
2109 gadgetfs_kill_sb (struct super_block
*sb
)
2111 kill_litter_super (sb
);
2113 put_dev (the_device
);
2118 /*----------------------------------------------------------------------*/
2120 static struct file_system_type gadgetfs_type
= {
2121 .owner
= THIS_MODULE
,
2123 .mount
= gadgetfs_mount
,
2124 .kill_sb
= gadgetfs_kill_sb
,
2126 MODULE_ALIAS_FS("gadgetfs");
2128 /*----------------------------------------------------------------------*/
2130 static int __init
init (void)
2134 status
= register_filesystem (&gadgetfs_type
);
2136 pr_info ("%s: %s, version " DRIVER_VERSION
"\n",
2137 shortname
, driver_desc
);
2142 static void __exit
cleanup (void)
2144 pr_debug ("unregister %s\n", shortname
);
2145 unregister_filesystem (&gadgetfs_type
);
2147 module_exit (cleanup
);