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 <linux/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>
29 #include <linux/uio.h>
30 #include <linux/refcount.h>
31 #include <linux/delay.h>
32 #include <linux/device.h>
33 #include <linux/moduleparam.h>
35 #include <linux/usb/gadgetfs.h>
36 #include <linux/usb/gadget.h>
40 * The gadgetfs API maps each endpoint to a file descriptor so that you
41 * can use standard synchronous read/write calls for I/O. There's some
42 * O_NONBLOCK and O_ASYNC/FASYNC style i/o support. Example usermode
43 * drivers show how this works in practice. You can also use AIO to
44 * eliminate I/O gaps between requests, to help when streaming data.
46 * Key parts that must be USB-specific are protocols defining how the
47 * read/write operations relate to the hardware state machines. There
48 * are two types of files. One type is for the device, implementing ep0.
49 * The other type is for each IN or OUT endpoint. In both cases, the
50 * user mode driver must configure the hardware before using it.
52 * - First, dev_config() is called when /dev/gadget/$CHIP is configured
53 * (by writing configuration and device descriptors). Afterwards it
54 * may serve as a source of device events, used to handle all control
55 * requests other than basic enumeration.
57 * - Then, after a SET_CONFIGURATION control request, ep_config() is
58 * called when each /dev/gadget/ep* file is configured (by writing
59 * endpoint descriptors). Afterwards these files are used to write()
60 * IN data or to read() OUT data. To halt the endpoint, a "wrong
61 * direction" request is issued (like reading an IN endpoint).
63 * Unlike "usbfs" the only ioctl()s are for things that are rare, and maybe
64 * not possible on all hardware. For example, precise fault handling with
65 * respect to data left in endpoint fifos after aborted operations; or
66 * selective clearing of endpoint halts, to implement SET_INTERFACE.
69 #define DRIVER_DESC "USB Gadget filesystem"
70 #define DRIVER_VERSION "24 Aug 2004"
72 static const char driver_desc
[] = DRIVER_DESC
;
73 static const char shortname
[] = "gadgetfs";
75 MODULE_DESCRIPTION (DRIVER_DESC
);
76 MODULE_AUTHOR ("David Brownell");
77 MODULE_LICENSE ("GPL");
79 static int ep_open(struct inode
*, struct file
*);
82 /*----------------------------------------------------------------------*/
84 #define GADGETFS_MAGIC 0xaee71ee7
86 /* /dev/gadget/$CHIP represents ep0 and the whole device */
88 /* DISABLED is the initial state. */
89 STATE_DEV_DISABLED
= 0,
91 /* Only one open() of /dev/gadget/$CHIP; only one file tracks
92 * ep0/device i/o modes and binding to the controller. Driver
93 * must always write descriptors to initialize the device, then
94 * the device becomes UNCONNECTED until enumeration.
98 /* From then on, ep0 fd is in either of two basic modes:
99 * - (UN)CONNECTED: read usb_gadgetfs_event(s) from it
100 * - SETUP: read/write will transfer control data and succeed;
101 * or if "wrong direction", performs protocol stall
103 STATE_DEV_UNCONNECTED
,
107 /* UNBOUND means the driver closed ep0, so the device won't be
108 * accessible again (DEV_DISABLED) until all fds are closed.
113 /* enough for the whole queue: most events invalidate others */
116 #define RBUF_SIZE 256
122 enum ep0_state state
; /* P: lock */
123 struct usb_gadgetfs_event event
[N_EVENT
];
125 struct fasync_struct
*fasync
;
128 /* drivers reading ep0 MUST handle control requests (SETUP)
129 * reported that way; else the host will time out.
131 unsigned usermode_setup
: 1,
137 gadget_registered
: 1;
138 unsigned setup_wLength
;
140 /* the rest is basically write-once */
141 struct usb_config_descriptor
*config
, *hs_config
;
142 struct usb_device_descriptor
*dev
;
143 struct usb_request
*req
;
144 struct usb_gadget
*gadget
;
145 struct list_head epfiles
;
147 wait_queue_head_t wait
;
148 struct super_block
*sb
;
149 struct dentry
*dentry
;
151 /* except this scratch i/o buffer for ep0 */
155 static inline void get_dev (struct dev_data
*data
)
157 refcount_inc (&data
->count
);
160 static void put_dev (struct dev_data
*data
)
162 if (likely (!refcount_dec_and_test (&data
->count
)))
164 /* needs no more cleanup */
165 BUG_ON (waitqueue_active (&data
->wait
));
169 static struct dev_data
*dev_new (void)
171 struct dev_data
*dev
;
173 dev
= kzalloc(sizeof(*dev
), GFP_KERNEL
);
176 dev
->state
= STATE_DEV_DISABLED
;
177 refcount_set (&dev
->count
, 1);
178 spin_lock_init (&dev
->lock
);
179 INIT_LIST_HEAD (&dev
->epfiles
);
180 init_waitqueue_head (&dev
->wait
);
184 /*----------------------------------------------------------------------*/
186 /* other /dev/gadget/$ENDPOINT files represent endpoints */
188 STATE_EP_DISABLED
= 0,
198 struct dev_data
*dev
;
199 /* must hold dev->lock before accessing ep or req */
201 struct usb_request
*req
;
204 struct usb_endpoint_descriptor desc
, hs_desc
;
205 struct list_head epfiles
;
206 wait_queue_head_t wait
;
207 struct dentry
*dentry
;
210 static inline void get_ep (struct ep_data
*data
)
212 refcount_inc (&data
->count
);
215 static void put_ep (struct ep_data
*data
)
217 if (likely (!refcount_dec_and_test (&data
->count
)))
220 /* needs no more cleanup */
221 BUG_ON (!list_empty (&data
->epfiles
));
222 BUG_ON (waitqueue_active (&data
->wait
));
226 /*----------------------------------------------------------------------*/
228 /* most "how to use the hardware" policy choices are in userspace:
229 * mapping endpoint roles (which the driver needs) to the capabilities
230 * which the usb controller has. most of those capabilities are exposed
231 * implicitly, starting with the driver name and then endpoint names.
234 static const char *CHIP
;
236 /*----------------------------------------------------------------------*/
238 /* NOTE: don't use dev_printk calls before binding to the gadget
239 * at the end of ep0 configuration, or after unbind.
242 /* too wordy: dev_printk(level , &(d)->gadget->dev , fmt , ## args) */
243 #define xprintk(d,level,fmt,args...) \
244 printk(level "%s: " fmt , shortname , ## args)
247 #define DBG(dev,fmt,args...) \
248 xprintk(dev , KERN_DEBUG , fmt , ## args)
250 #define DBG(dev,fmt,args...) \
257 #define VDEBUG(dev,fmt,args...) \
261 #define ERROR(dev,fmt,args...) \
262 xprintk(dev , KERN_ERR , fmt , ## args)
263 #define INFO(dev,fmt,args...) \
264 xprintk(dev , KERN_INFO , fmt , ## args)
267 /*----------------------------------------------------------------------*/
269 /* SYNCHRONOUS ENDPOINT OPERATIONS (bulk/intr/iso)
271 * After opening, configure non-control endpoints. Then use normal
272 * stream read() and write() requests; and maybe ioctl() to get more
273 * precise FIFO status when recovering from cancellation.
276 static void epio_complete (struct usb_ep
*ep
, struct usb_request
*req
)
278 struct ep_data
*epdata
= ep
->driver_data
;
283 epdata
->status
= req
->status
;
285 epdata
->status
= req
->actual
;
286 complete ((struct completion
*)req
->context
);
289 /* tasklock endpoint, returning when it's connected.
290 * still need dev->lock to use epdata->ep.
293 get_ready_ep (unsigned f_flags
, struct ep_data
*epdata
, bool is_write
)
297 if (f_flags
& O_NONBLOCK
) {
298 if (!mutex_trylock(&epdata
->lock
))
300 if (epdata
->state
!= STATE_EP_ENABLED
&&
301 (!is_write
|| epdata
->state
!= STATE_EP_READY
)) {
302 mutex_unlock(&epdata
->lock
);
310 val
= mutex_lock_interruptible(&epdata
->lock
);
314 switch (epdata
->state
) {
315 case STATE_EP_ENABLED
:
317 case STATE_EP_READY
: /* not configured yet */
321 case STATE_EP_UNBOUND
: /* clean disconnect */
323 // case STATE_EP_DISABLED: /* "can't happen" */
324 default: /* error! */
325 pr_debug ("%s: ep %p not available, state %d\n",
326 shortname
, epdata
, epdata
->state
);
328 mutex_unlock(&epdata
->lock
);
333 ep_io (struct ep_data
*epdata
, void *buf
, unsigned len
)
335 DECLARE_COMPLETION_ONSTACK (done
);
338 spin_lock_irq (&epdata
->dev
->lock
);
339 if (likely (epdata
->ep
!= NULL
)) {
340 struct usb_request
*req
= epdata
->req
;
342 req
->context
= &done
;
343 req
->complete
= epio_complete
;
346 value
= usb_ep_queue (epdata
->ep
, req
, GFP_ATOMIC
);
349 spin_unlock_irq (&epdata
->dev
->lock
);
351 if (likely (value
== 0)) {
352 value
= wait_event_interruptible (done
.wait
, done
.done
);
354 spin_lock_irq (&epdata
->dev
->lock
);
355 if (likely (epdata
->ep
!= NULL
)) {
356 DBG (epdata
->dev
, "%s i/o interrupted\n",
358 usb_ep_dequeue (epdata
->ep
, epdata
->req
);
359 spin_unlock_irq (&epdata
->dev
->lock
);
361 wait_event (done
.wait
, done
.done
);
362 if (epdata
->status
== -ECONNRESET
)
363 epdata
->status
= -EINTR
;
365 spin_unlock_irq (&epdata
->dev
->lock
);
367 DBG (epdata
->dev
, "endpoint gone\n");
368 epdata
->status
= -ENODEV
;
371 return epdata
->status
;
377 ep_release (struct inode
*inode
, struct file
*fd
)
379 struct ep_data
*data
= fd
->private_data
;
382 value
= mutex_lock_interruptible(&data
->lock
);
386 /* clean up if this can be reopened */
387 if (data
->state
!= STATE_EP_UNBOUND
) {
388 data
->state
= STATE_EP_DISABLED
;
389 data
->desc
.bDescriptorType
= 0;
390 data
->hs_desc
.bDescriptorType
= 0;
391 usb_ep_disable(data
->ep
);
393 mutex_unlock(&data
->lock
);
398 static long ep_ioctl(struct file
*fd
, unsigned code
, unsigned long value
)
400 struct ep_data
*data
= fd
->private_data
;
403 if ((status
= get_ready_ep (fd
->f_flags
, data
, false)) < 0)
406 spin_lock_irq (&data
->dev
->lock
);
407 if (likely (data
->ep
!= NULL
)) {
409 case GADGETFS_FIFO_STATUS
:
410 status
= usb_ep_fifo_status (data
->ep
);
412 case GADGETFS_FIFO_FLUSH
:
413 usb_ep_fifo_flush (data
->ep
);
415 case GADGETFS_CLEAR_HALT
:
416 status
= usb_ep_clear_halt (data
->ep
);
423 spin_unlock_irq (&data
->dev
->lock
);
424 mutex_unlock(&data
->lock
);
428 /*----------------------------------------------------------------------*/
430 /* ASYNCHRONOUS ENDPOINT I/O OPERATIONS (bulk/intr/iso) */
433 struct usb_request
*req
;
434 struct ep_data
*epdata
;
436 struct mm_struct
*mm
;
437 struct work_struct work
;
444 static int ep_aio_cancel(struct kiocb
*iocb
)
446 struct kiocb_priv
*priv
= iocb
->private;
447 struct ep_data
*epdata
;
451 epdata
= priv
->epdata
;
452 // spin_lock(&epdata->dev->lock);
453 if (likely(epdata
&& epdata
->ep
&& priv
->req
))
454 value
= usb_ep_dequeue (epdata
->ep
, priv
->req
);
457 // spin_unlock(&epdata->dev->lock);
463 static void ep_user_copy_worker(struct work_struct
*work
)
465 struct kiocb_priv
*priv
= container_of(work
, struct kiocb_priv
, work
);
466 struct mm_struct
*mm
= priv
->mm
;
467 struct kiocb
*iocb
= priv
->iocb
;
471 ret
= copy_to_iter(priv
->buf
, priv
->actual
, &priv
->to
);
476 /* completing the iocb can drop the ctx and mm, don't touch mm after */
477 iocb
->ki_complete(iocb
, ret
, ret
);
480 kfree(priv
->to_free
);
484 static void ep_aio_complete(struct usb_ep
*ep
, struct usb_request
*req
)
486 struct kiocb
*iocb
= req
->context
;
487 struct kiocb_priv
*priv
= iocb
->private;
488 struct ep_data
*epdata
= priv
->epdata
;
490 /* lock against disconnect (and ideally, cancel) */
491 spin_lock(&epdata
->dev
->lock
);
495 /* if this was a write or a read returning no data then we
496 * don't need to copy anything to userspace, so we can
497 * complete the aio request immediately.
499 if (priv
->to_free
== NULL
|| unlikely(req
->actual
== 0)) {
501 kfree(priv
->to_free
);
503 iocb
->private = NULL
;
504 /* aio_complete() reports bytes-transferred _and_ faults */
506 iocb
->ki_complete(iocb
, req
->actual
? req
->actual
: req
->status
,
509 /* ep_copy_to_user() won't report both; we hide some faults */
510 if (unlikely(0 != req
->status
))
511 DBG(epdata
->dev
, "%s fault %d len %d\n",
512 ep
->name
, req
->status
, req
->actual
);
514 priv
->buf
= req
->buf
;
515 priv
->actual
= req
->actual
;
516 INIT_WORK(&priv
->work
, ep_user_copy_worker
);
517 schedule_work(&priv
->work
);
520 usb_ep_free_request(ep
, req
);
521 spin_unlock(&epdata
->dev
->lock
);
525 static ssize_t
ep_aio(struct kiocb
*iocb
,
526 struct kiocb_priv
*priv
,
527 struct ep_data
*epdata
,
531 struct usb_request
*req
;
534 iocb
->private = priv
;
537 kiocb_set_cancel_fn(iocb
, ep_aio_cancel
);
539 priv
->epdata
= epdata
;
541 priv
->mm
= current
->mm
; /* mm teardown waits for iocbs in exit_aio() */
543 /* each kiocb is coupled to one usb_request, but we can't
544 * allocate or submit those if the host disconnected.
546 spin_lock_irq(&epdata
->dev
->lock
);
548 if (unlikely(epdata
->ep
== NULL
))
551 req
= usb_ep_alloc_request(epdata
->ep
, GFP_ATOMIC
);
559 req
->complete
= ep_aio_complete
;
561 value
= usb_ep_queue(epdata
->ep
, req
, GFP_ATOMIC
);
562 if (unlikely(0 != value
)) {
563 usb_ep_free_request(epdata
->ep
, req
);
566 spin_unlock_irq(&epdata
->dev
->lock
);
570 spin_unlock_irq(&epdata
->dev
->lock
);
571 kfree(priv
->to_free
);
578 ep_read_iter(struct kiocb
*iocb
, struct iov_iter
*to
)
580 struct file
*file
= iocb
->ki_filp
;
581 struct ep_data
*epdata
= file
->private_data
;
582 size_t len
= iov_iter_count(to
);
586 if ((value
= get_ready_ep(file
->f_flags
, epdata
, false)) < 0)
589 /* halt any endpoint by doing a "wrong direction" i/o call */
590 if (usb_endpoint_dir_in(&epdata
->desc
)) {
591 if (usb_endpoint_xfer_isoc(&epdata
->desc
) ||
592 !is_sync_kiocb(iocb
)) {
593 mutex_unlock(&epdata
->lock
);
596 DBG (epdata
->dev
, "%s halt\n", epdata
->name
);
597 spin_lock_irq(&epdata
->dev
->lock
);
598 if (likely(epdata
->ep
!= NULL
))
599 usb_ep_set_halt(epdata
->ep
);
600 spin_unlock_irq(&epdata
->dev
->lock
);
601 mutex_unlock(&epdata
->lock
);
605 buf
= kmalloc(len
, GFP_KERNEL
);
606 if (unlikely(!buf
)) {
607 mutex_unlock(&epdata
->lock
);
610 if (is_sync_kiocb(iocb
)) {
611 value
= ep_io(epdata
, buf
, len
);
612 if (value
>= 0 && (copy_to_iter(buf
, value
, to
) != value
))
615 struct kiocb_priv
*priv
= kzalloc(sizeof *priv
, GFP_KERNEL
);
619 priv
->to_free
= dup_iter(&priv
->to
, to
, GFP_KERNEL
);
620 if (!priv
->to_free
) {
624 value
= ep_aio(iocb
, priv
, epdata
, buf
, len
);
625 if (value
== -EIOCBQUEUED
)
630 mutex_unlock(&epdata
->lock
);
634 static ssize_t
ep_config(struct ep_data
*, const char *, size_t);
637 ep_write_iter(struct kiocb
*iocb
, struct iov_iter
*from
)
639 struct file
*file
= iocb
->ki_filp
;
640 struct ep_data
*epdata
= file
->private_data
;
641 size_t len
= iov_iter_count(from
);
646 if ((value
= get_ready_ep(file
->f_flags
, epdata
, true)) < 0)
649 configured
= epdata
->state
== STATE_EP_ENABLED
;
651 /* halt any endpoint by doing a "wrong direction" i/o call */
652 if (configured
&& !usb_endpoint_dir_in(&epdata
->desc
)) {
653 if (usb_endpoint_xfer_isoc(&epdata
->desc
) ||
654 !is_sync_kiocb(iocb
)) {
655 mutex_unlock(&epdata
->lock
);
658 DBG (epdata
->dev
, "%s halt\n", epdata
->name
);
659 spin_lock_irq(&epdata
->dev
->lock
);
660 if (likely(epdata
->ep
!= NULL
))
661 usb_ep_set_halt(epdata
->ep
);
662 spin_unlock_irq(&epdata
->dev
->lock
);
663 mutex_unlock(&epdata
->lock
);
667 buf
= kmalloc(len
, GFP_KERNEL
);
668 if (unlikely(!buf
)) {
669 mutex_unlock(&epdata
->lock
);
673 if (unlikely(!copy_from_iter_full(buf
, len
, from
))) {
678 if (unlikely(!configured
)) {
679 value
= ep_config(epdata
, buf
, len
);
680 } else if (is_sync_kiocb(iocb
)) {
681 value
= ep_io(epdata
, buf
, len
);
683 struct kiocb_priv
*priv
= kzalloc(sizeof *priv
, GFP_KERNEL
);
686 value
= ep_aio(iocb
, priv
, epdata
, buf
, len
);
687 if (value
== -EIOCBQUEUED
)
693 mutex_unlock(&epdata
->lock
);
697 /*----------------------------------------------------------------------*/
699 /* used after endpoint configuration */
700 static const struct file_operations ep_io_operations
= {
701 .owner
= THIS_MODULE
,
704 .release
= ep_release
,
706 .unlocked_ioctl
= ep_ioctl
,
707 .read_iter
= ep_read_iter
,
708 .write_iter
= ep_write_iter
,
711 /* ENDPOINT INITIALIZATION
713 * fd = open ("/dev/gadget/$ENDPOINT", O_RDWR)
714 * status = write (fd, descriptors, sizeof descriptors)
716 * That write establishes the endpoint configuration, configuring
717 * the controller to process bulk, interrupt, or isochronous transfers
718 * at the right maxpacket size, and so on.
720 * The descriptors are message type 1, identified by a host order u32
721 * at the beginning of what's written. Descriptor order is: full/low
722 * speed descriptor, then optional high speed descriptor.
725 ep_config (struct ep_data
*data
, const char *buf
, size_t len
)
729 int value
, length
= len
;
731 if (data
->state
!= STATE_EP_READY
) {
737 if (len
< USB_DT_ENDPOINT_SIZE
+ 4)
740 /* we might need to change message format someday */
741 memcpy(&tag
, buf
, 4);
743 DBG(data
->dev
, "config %s, bad tag %d\n", data
->name
, tag
);
749 /* NOTE: audio endpoint extensions not accepted here;
750 * just don't include the extra bytes.
753 /* full/low speed descriptor, then high speed */
754 memcpy(&data
->desc
, buf
, USB_DT_ENDPOINT_SIZE
);
755 if (data
->desc
.bLength
!= USB_DT_ENDPOINT_SIZE
756 || data
->desc
.bDescriptorType
!= USB_DT_ENDPOINT
)
758 if (len
!= USB_DT_ENDPOINT_SIZE
) {
759 if (len
!= 2 * USB_DT_ENDPOINT_SIZE
)
761 memcpy(&data
->hs_desc
, buf
+ USB_DT_ENDPOINT_SIZE
,
762 USB_DT_ENDPOINT_SIZE
);
763 if (data
->hs_desc
.bLength
!= USB_DT_ENDPOINT_SIZE
764 || data
->hs_desc
.bDescriptorType
765 != USB_DT_ENDPOINT
) {
766 DBG(data
->dev
, "config %s, bad hs length or type\n",
772 spin_lock_irq (&data
->dev
->lock
);
773 if (data
->dev
->state
== STATE_DEV_UNBOUND
) {
783 switch (data
->dev
->gadget
->speed
) {
786 ep
->desc
= &data
->desc
;
789 /* fails if caller didn't provide that descriptor... */
790 ep
->desc
= &data
->hs_desc
;
793 DBG(data
->dev
, "unconnected, %s init abandoned\n",
798 value
= usb_ep_enable(ep
);
800 data
->state
= STATE_EP_ENABLED
;
804 spin_unlock_irq (&data
->dev
->lock
);
807 data
->desc
.bDescriptorType
= 0;
808 data
->hs_desc
.bDescriptorType
= 0;
817 ep_open (struct inode
*inode
, struct file
*fd
)
819 struct ep_data
*data
= inode
->i_private
;
822 if (mutex_lock_interruptible(&data
->lock
) != 0)
824 spin_lock_irq (&data
->dev
->lock
);
825 if (data
->dev
->state
== STATE_DEV_UNBOUND
)
827 else if (data
->state
== STATE_EP_DISABLED
) {
829 data
->state
= STATE_EP_READY
;
831 fd
->private_data
= data
;
832 VDEBUG (data
->dev
, "%s ready\n", data
->name
);
834 DBG (data
->dev
, "%s state %d\n",
835 data
->name
, data
->state
);
836 spin_unlock_irq (&data
->dev
->lock
);
837 mutex_unlock(&data
->lock
);
841 /*----------------------------------------------------------------------*/
843 /* EP0 IMPLEMENTATION can be partly in userspace.
845 * Drivers that use this facility receive various events, including
846 * control requests the kernel doesn't handle. Drivers that don't
847 * use this facility may be too simple-minded for real applications.
850 static inline void ep0_readable (struct dev_data
*dev
)
852 wake_up (&dev
->wait
);
853 kill_fasync (&dev
->fasync
, SIGIO
, POLL_IN
);
856 static void clean_req (struct usb_ep
*ep
, struct usb_request
*req
)
858 struct dev_data
*dev
= ep
->driver_data
;
860 if (req
->buf
!= dev
->rbuf
) {
862 req
->buf
= dev
->rbuf
;
864 req
->complete
= epio_complete
;
865 dev
->setup_out_ready
= 0;
868 static void ep0_complete (struct usb_ep
*ep
, struct usb_request
*req
)
870 struct dev_data
*dev
= ep
->driver_data
;
874 /* for control OUT, data must still get to userspace */
875 spin_lock_irqsave(&dev
->lock
, flags
);
876 if (!dev
->setup_in
) {
877 dev
->setup_out_error
= (req
->status
!= 0);
878 if (!dev
->setup_out_error
)
880 dev
->setup_out_ready
= 1;
884 /* clean up as appropriate */
885 if (free
&& req
->buf
!= &dev
->rbuf
)
887 req
->complete
= epio_complete
;
888 spin_unlock_irqrestore(&dev
->lock
, flags
);
891 static int setup_req (struct usb_ep
*ep
, struct usb_request
*req
, u16 len
)
893 struct dev_data
*dev
= ep
->driver_data
;
895 if (dev
->setup_out_ready
) {
896 DBG (dev
, "ep0 request busy!\n");
899 if (len
> sizeof (dev
->rbuf
))
900 req
->buf
= kmalloc(len
, GFP_ATOMIC
);
901 if (req
->buf
== NULL
) {
902 req
->buf
= dev
->rbuf
;
905 req
->complete
= ep0_complete
;
912 ep0_read (struct file
*fd
, char __user
*buf
, size_t len
, loff_t
*ptr
)
914 struct dev_data
*dev
= fd
->private_data
;
916 enum ep0_state state
;
918 spin_lock_irq (&dev
->lock
);
919 if (dev
->state
<= STATE_DEV_OPENED
) {
924 /* report fd mode change before acting on it */
925 if (dev
->setup_abort
) {
926 dev
->setup_abort
= 0;
931 /* control DATA stage */
932 if ((state
= dev
->state
) == STATE_DEV_SETUP
) {
934 if (dev
->setup_in
) { /* stall IN */
935 VDEBUG(dev
, "ep0in stall\n");
936 (void) usb_ep_set_halt (dev
->gadget
->ep0
);
938 dev
->state
= STATE_DEV_CONNECTED
;
940 } else if (len
== 0) { /* ack SET_CONFIGURATION etc */
941 struct usb_ep
*ep
= dev
->gadget
->ep0
;
942 struct usb_request
*req
= dev
->req
;
944 if ((retval
= setup_req (ep
, req
, 0)) == 0) {
946 spin_unlock_irq (&dev
->lock
);
947 retval
= usb_ep_queue (ep
, req
, GFP_KERNEL
);
948 spin_lock_irq (&dev
->lock
);
951 dev
->state
= STATE_DEV_CONNECTED
;
953 /* assume that was SET_CONFIGURATION */
954 if (dev
->current_config
) {
957 if (gadget_is_dualspeed(dev
->gadget
)
958 && (dev
->gadget
->speed
960 power
= dev
->hs_config
->bMaxPower
;
962 power
= dev
->config
->bMaxPower
;
963 usb_gadget_vbus_draw(dev
->gadget
, 2 * power
);
966 } else { /* collect OUT data */
967 if ((fd
->f_flags
& O_NONBLOCK
) != 0
968 && !dev
->setup_out_ready
) {
972 spin_unlock_irq (&dev
->lock
);
973 retval
= wait_event_interruptible (dev
->wait
,
974 dev
->setup_out_ready
!= 0);
976 /* FIXME state could change from under us */
977 spin_lock_irq (&dev
->lock
);
981 if (dev
->state
!= STATE_DEV_SETUP
) {
985 dev
->state
= STATE_DEV_CONNECTED
;
987 if (dev
->setup_out_error
)
990 len
= min (len
, (size_t)dev
->req
->actual
);
992 spin_unlock_irq(&dev
->lock
);
993 if (copy_to_user (buf
, dev
->req
->buf
, len
))
997 spin_lock_irq(&dev
->lock
);
999 clean_req (dev
->gadget
->ep0
, dev
->req
);
1000 /* NOTE userspace can't yet choose to stall */
1006 /* else normal: return event data */
1007 if (len
< sizeof dev
->event
[0]) {
1011 len
-= len
% sizeof (struct usb_gadgetfs_event
);
1012 dev
->usermode_setup
= 1;
1015 /* return queued events right away */
1016 if (dev
->ev_next
!= 0) {
1019 n
= len
/ sizeof (struct usb_gadgetfs_event
);
1020 if (dev
->ev_next
< n
)
1023 /* ep0 i/o has special semantics during STATE_DEV_SETUP */
1024 for (i
= 0; i
< n
; i
++) {
1025 if (dev
->event
[i
].type
== GADGETFS_SETUP
) {
1026 dev
->state
= STATE_DEV_SETUP
;
1031 spin_unlock_irq (&dev
->lock
);
1032 len
= n
* sizeof (struct usb_gadgetfs_event
);
1033 if (copy_to_user (buf
, &dev
->event
, len
))
1038 /* NOTE this doesn't guard against broken drivers;
1039 * concurrent ep0 readers may lose events.
1041 spin_lock_irq (&dev
->lock
);
1042 if (dev
->ev_next
> n
) {
1043 memmove(&dev
->event
[0], &dev
->event
[n
],
1044 sizeof (struct usb_gadgetfs_event
)
1045 * (dev
->ev_next
- n
));
1048 spin_unlock_irq (&dev
->lock
);
1052 if (fd
->f_flags
& O_NONBLOCK
) {
1059 DBG (dev
, "fail %s, state %d\n", __func__
, state
);
1062 case STATE_DEV_UNCONNECTED
:
1063 case STATE_DEV_CONNECTED
:
1064 spin_unlock_irq (&dev
->lock
);
1065 DBG (dev
, "%s wait\n", __func__
);
1067 /* wait for events */
1068 retval
= wait_event_interruptible (dev
->wait
,
1072 spin_lock_irq (&dev
->lock
);
1077 spin_unlock_irq (&dev
->lock
);
1081 static struct usb_gadgetfs_event
*
1082 next_event (struct dev_data
*dev
, enum usb_gadgetfs_event_type type
)
1084 struct usb_gadgetfs_event
*event
;
1088 /* these events purge the queue */
1089 case GADGETFS_DISCONNECT
:
1090 if (dev
->state
== STATE_DEV_SETUP
)
1091 dev
->setup_abort
= 1;
1093 case GADGETFS_CONNECT
:
1096 case GADGETFS_SETUP
: /* previous request timed out */
1097 case GADGETFS_SUSPEND
: /* same effect */
1098 /* these events can't be repeated */
1099 for (i
= 0; i
!= dev
->ev_next
; i
++) {
1100 if (dev
->event
[i
].type
!= type
)
1102 DBG(dev
, "discard old event[%d] %d\n", i
, type
);
1104 if (i
== dev
->ev_next
)
1106 /* indices start at zero, for simplicity */
1107 memmove (&dev
->event
[i
], &dev
->event
[i
+ 1],
1108 sizeof (struct usb_gadgetfs_event
)
1109 * (dev
->ev_next
- i
));
1115 VDEBUG(dev
, "event[%d] = %d\n", dev
->ev_next
, type
);
1116 event
= &dev
->event
[dev
->ev_next
++];
1117 BUG_ON (dev
->ev_next
> N_EVENT
);
1118 memset (event
, 0, sizeof *event
);
1124 ep0_write (struct file
*fd
, const char __user
*buf
, size_t len
, loff_t
*ptr
)
1126 struct dev_data
*dev
= fd
->private_data
;
1127 ssize_t retval
= -ESRCH
;
1129 /* report fd mode change before acting on it */
1130 if (dev
->setup_abort
) {
1131 dev
->setup_abort
= 0;
1134 /* data and/or status stage for control request */
1135 } else if (dev
->state
== STATE_DEV_SETUP
) {
1137 len
= min_t(size_t, len
, dev
->setup_wLength
);
1138 if (dev
->setup_in
) {
1139 retval
= setup_req (dev
->gadget
->ep0
, dev
->req
, len
);
1141 dev
->state
= STATE_DEV_CONNECTED
;
1143 spin_unlock_irq (&dev
->lock
);
1144 if (copy_from_user (dev
->req
->buf
, buf
, len
))
1147 if (len
< dev
->setup_wLength
)
1149 retval
= usb_ep_queue (
1150 dev
->gadget
->ep0
, dev
->req
,
1153 spin_lock_irq(&dev
->lock
);
1156 clean_req (dev
->gadget
->ep0
, dev
->req
);
1163 /* can stall some OUT transfers */
1164 } else if (dev
->setup_can_stall
) {
1165 VDEBUG(dev
, "ep0out stall\n");
1166 (void) usb_ep_set_halt (dev
->gadget
->ep0
);
1168 dev
->state
= STATE_DEV_CONNECTED
;
1170 DBG(dev
, "bogus ep0out stall!\n");
1173 DBG (dev
, "fail %s, state %d\n", __func__
, dev
->state
);
1179 ep0_fasync (int f
, struct file
*fd
, int on
)
1181 struct dev_data
*dev
= fd
->private_data
;
1182 // caller must F_SETOWN before signal delivery happens
1183 VDEBUG (dev
, "%s %s\n", __func__
, on
? "on" : "off");
1184 return fasync_helper (f
, fd
, on
, &dev
->fasync
);
1187 static struct usb_gadget_driver gadgetfs_driver
;
1190 dev_release (struct inode
*inode
, struct file
*fd
)
1192 struct dev_data
*dev
= fd
->private_data
;
1194 /* closing ep0 === shutdown all */
1196 if (dev
->gadget_registered
) {
1197 usb_gadget_unregister_driver (&gadgetfs_driver
);
1198 dev
->gadget_registered
= false;
1201 /* at this point "good" hardware has disconnected the
1202 * device from USB; the host won't see it any more.
1203 * alternatively, all host requests will time out.
1209 /* other endpoints were all decoupled from this device */
1210 spin_lock_irq(&dev
->lock
);
1211 dev
->state
= STATE_DEV_DISABLED
;
1212 spin_unlock_irq(&dev
->lock
);
1219 ep0_poll (struct file
*fd
, poll_table
*wait
)
1221 struct dev_data
*dev
= fd
->private_data
;
1224 if (dev
->state
<= STATE_DEV_OPENED
)
1225 return DEFAULT_POLLMASK
;
1227 poll_wait(fd
, &dev
->wait
, wait
);
1229 spin_lock_irq (&dev
->lock
);
1231 /* report fd mode change before acting on it */
1232 if (dev
->setup_abort
) {
1233 dev
->setup_abort
= 0;
1238 if (dev
->state
== STATE_DEV_SETUP
) {
1239 if (dev
->setup_in
|| dev
->setup_can_stall
)
1242 if (dev
->ev_next
!= 0)
1246 spin_unlock_irq(&dev
->lock
);
1250 static long dev_ioctl (struct file
*fd
, unsigned code
, unsigned long value
)
1252 struct dev_data
*dev
= fd
->private_data
;
1253 struct usb_gadget
*gadget
= dev
->gadget
;
1256 spin_lock_irq(&dev
->lock
);
1257 if (dev
->state
== STATE_DEV_OPENED
||
1258 dev
->state
== STATE_DEV_UNBOUND
) {
1259 /* Not bound to a UDC */
1260 } else if (gadget
->ops
->ioctl
) {
1262 spin_unlock_irq(&dev
->lock
);
1264 ret
= gadget
->ops
->ioctl (gadget
, code
, value
);
1266 spin_lock_irq(&dev
->lock
);
1269 spin_unlock_irq(&dev
->lock
);
1274 /*----------------------------------------------------------------------*/
1276 /* The in-kernel gadget driver handles most ep0 issues, in particular
1277 * enumerating the single configuration (as provided from user space).
1279 * Unrecognized ep0 requests may be handled in user space.
1282 static void make_qualifier (struct dev_data
*dev
)
1284 struct usb_qualifier_descriptor qual
;
1285 struct usb_device_descriptor
*desc
;
1287 qual
.bLength
= sizeof qual
;
1288 qual
.bDescriptorType
= USB_DT_DEVICE_QUALIFIER
;
1289 qual
.bcdUSB
= cpu_to_le16 (0x0200);
1292 qual
.bDeviceClass
= desc
->bDeviceClass
;
1293 qual
.bDeviceSubClass
= desc
->bDeviceSubClass
;
1294 qual
.bDeviceProtocol
= desc
->bDeviceProtocol
;
1296 /* assumes ep0 uses the same value for both speeds ... */
1297 qual
.bMaxPacketSize0
= dev
->gadget
->ep0
->maxpacket
;
1299 qual
.bNumConfigurations
= 1;
1302 memcpy (dev
->rbuf
, &qual
, sizeof qual
);
1306 config_buf (struct dev_data
*dev
, u8 type
, unsigned index
)
1311 /* only one configuration */
1315 if (gadget_is_dualspeed(dev
->gadget
)) {
1316 hs
= (dev
->gadget
->speed
== USB_SPEED_HIGH
);
1317 if (type
== USB_DT_OTHER_SPEED_CONFIG
)
1321 dev
->req
->buf
= dev
->hs_config
;
1322 len
= le16_to_cpu(dev
->hs_config
->wTotalLength
);
1324 dev
->req
->buf
= dev
->config
;
1325 len
= le16_to_cpu(dev
->config
->wTotalLength
);
1327 ((u8
*)dev
->req
->buf
) [1] = type
;
1332 gadgetfs_setup (struct usb_gadget
*gadget
, const struct usb_ctrlrequest
*ctrl
)
1334 struct dev_data
*dev
= get_gadget_data (gadget
);
1335 struct usb_request
*req
= dev
->req
;
1336 int value
= -EOPNOTSUPP
;
1337 struct usb_gadgetfs_event
*event
;
1338 u16 w_value
= le16_to_cpu(ctrl
->wValue
);
1339 u16 w_length
= le16_to_cpu(ctrl
->wLength
);
1341 if (w_length
> RBUF_SIZE
) {
1342 if (ctrl
->bRequestType
& USB_DIR_IN
) {
1343 /* Cast away the const, we are going to overwrite on purpose. */
1344 __le16
*temp
= (__le16
*)&ctrl
->wLength
;
1346 *temp
= cpu_to_le16(RBUF_SIZE
);
1347 w_length
= RBUF_SIZE
;
1353 spin_lock (&dev
->lock
);
1354 dev
->setup_abort
= 0;
1355 if (dev
->state
== STATE_DEV_UNCONNECTED
) {
1356 if (gadget_is_dualspeed(gadget
)
1357 && gadget
->speed
== USB_SPEED_HIGH
1358 && dev
->hs_config
== NULL
) {
1359 spin_unlock(&dev
->lock
);
1360 ERROR (dev
, "no high speed config??\n");
1364 dev
->state
= STATE_DEV_CONNECTED
;
1366 INFO (dev
, "connected\n");
1367 event
= next_event (dev
, GADGETFS_CONNECT
);
1368 event
->u
.speed
= gadget
->speed
;
1371 /* host may have given up waiting for response. we can miss control
1372 * requests handled lower down (device/endpoint status and features);
1373 * then ep0_{read,write} will report the wrong status. controller
1374 * driver will have aborted pending i/o.
1376 } else if (dev
->state
== STATE_DEV_SETUP
)
1377 dev
->setup_abort
= 1;
1379 req
->buf
= dev
->rbuf
;
1380 req
->context
= NULL
;
1381 value
= -EOPNOTSUPP
;
1382 switch (ctrl
->bRequest
) {
1384 case USB_REQ_GET_DESCRIPTOR
:
1385 if (ctrl
->bRequestType
!= USB_DIR_IN
)
1387 switch (w_value
>> 8) {
1390 value
= min (w_length
, (u16
) sizeof *dev
->dev
);
1391 dev
->dev
->bMaxPacketSize0
= dev
->gadget
->ep0
->maxpacket
;
1392 req
->buf
= dev
->dev
;
1394 case USB_DT_DEVICE_QUALIFIER
:
1395 if (!dev
->hs_config
)
1397 value
= min (w_length
, (u16
)
1398 sizeof (struct usb_qualifier_descriptor
));
1399 make_qualifier (dev
);
1401 case USB_DT_OTHER_SPEED_CONFIG
:
1404 value
= config_buf (dev
,
1408 value
= min (w_length
, (u16
) value
);
1413 default: // all others are errors
1418 /* currently one config, two speeds */
1419 case USB_REQ_SET_CONFIGURATION
:
1420 if (ctrl
->bRequestType
!= 0)
1422 if (0 == (u8
) w_value
) {
1424 dev
->current_config
= 0;
1425 usb_gadget_vbus_draw(gadget
, 8 /* mA */ );
1426 // user mode expected to disable endpoints
1430 if (gadget_is_dualspeed(gadget
)
1431 && gadget
->speed
== USB_SPEED_HIGH
) {
1432 config
= dev
->hs_config
->bConfigurationValue
;
1433 power
= dev
->hs_config
->bMaxPower
;
1435 config
= dev
->config
->bConfigurationValue
;
1436 power
= dev
->config
->bMaxPower
;
1439 if (config
== (u8
) w_value
) {
1441 dev
->current_config
= config
;
1442 usb_gadget_vbus_draw(gadget
, 2 * power
);
1446 /* report SET_CONFIGURATION like any other control request,
1447 * except that usermode may not stall this. the next
1448 * request mustn't be allowed start until this finishes:
1449 * endpoints and threads set up, etc.
1451 * NOTE: older PXA hardware (before PXA 255: without UDCCFR)
1452 * has bad/racey automagic that prevents synchronizing here.
1453 * even kernel mode drivers often miss them.
1456 INFO (dev
, "configuration #%d\n", dev
->current_config
);
1457 usb_gadget_set_state(gadget
, USB_STATE_CONFIGURED
);
1458 if (dev
->usermode_setup
) {
1459 dev
->setup_can_stall
= 0;
1465 #ifndef CONFIG_USB_PXA25X
1466 /* PXA automagically handles this request too */
1467 case USB_REQ_GET_CONFIGURATION
:
1468 if (ctrl
->bRequestType
!= 0x80)
1470 *(u8
*)req
->buf
= dev
->current_config
;
1471 value
= min (w_length
, (u16
) 1);
1477 VDEBUG (dev
, "%s req%02x.%02x v%04x i%04x l%d\n",
1478 dev
->usermode_setup
? "delegate" : "fail",
1479 ctrl
->bRequestType
, ctrl
->bRequest
,
1480 w_value
, le16_to_cpu(ctrl
->wIndex
), w_length
);
1482 /* if there's an ep0 reader, don't stall */
1483 if (dev
->usermode_setup
) {
1484 dev
->setup_can_stall
= 1;
1486 dev
->setup_in
= (ctrl
->bRequestType
& USB_DIR_IN
)
1488 dev
->setup_wLength
= w_length
;
1489 dev
->setup_out_ready
= 0;
1490 dev
->setup_out_error
= 0;
1493 /* read DATA stage for OUT right away */
1494 if (unlikely (!dev
->setup_in
&& w_length
)) {
1495 value
= setup_req (gadget
->ep0
, dev
->req
,
1501 spin_unlock (&dev
->lock
);
1502 value
= usb_ep_queue (gadget
->ep0
, dev
->req
,
1504 spin_lock (&dev
->lock
);
1507 clean_req (gadget
->ep0
, dev
->req
);
1511 /* we can't currently stall these */
1512 dev
->setup_can_stall
= 0;
1515 /* state changes when reader collects event */
1516 event
= next_event (dev
, GADGETFS_SETUP
);
1517 event
->u
.setup
= *ctrl
;
1519 spin_unlock (&dev
->lock
);
1524 /* proceed with data transfer and status phases? */
1525 if (value
>= 0 && dev
->state
!= STATE_DEV_SETUP
) {
1526 req
->length
= value
;
1527 req
->zero
= value
< w_length
;
1530 spin_unlock (&dev
->lock
);
1531 value
= usb_ep_queue (gadget
->ep0
, req
, GFP_KERNEL
);
1532 spin_lock(&dev
->lock
);
1534 spin_unlock(&dev
->lock
);
1536 DBG (dev
, "ep_queue --> %d\n", value
);
1542 /* device stalls when value < 0 */
1543 spin_unlock (&dev
->lock
);
1547 static void destroy_ep_files (struct dev_data
*dev
)
1549 DBG (dev
, "%s %d\n", __func__
, dev
->state
);
1551 /* dev->state must prevent interference */
1552 spin_lock_irq (&dev
->lock
);
1553 while (!list_empty(&dev
->epfiles
)) {
1555 struct inode
*parent
;
1556 struct dentry
*dentry
;
1558 /* break link to FS */
1559 ep
= list_first_entry (&dev
->epfiles
, struct ep_data
, epfiles
);
1560 list_del_init (&ep
->epfiles
);
1561 spin_unlock_irq (&dev
->lock
);
1563 dentry
= ep
->dentry
;
1565 parent
= d_inode(dentry
->d_parent
);
1567 /* break link to controller */
1568 mutex_lock(&ep
->lock
);
1569 if (ep
->state
== STATE_EP_ENABLED
)
1570 (void) usb_ep_disable (ep
->ep
);
1571 ep
->state
= STATE_EP_UNBOUND
;
1572 usb_ep_free_request (ep
->ep
, ep
->req
);
1574 mutex_unlock(&ep
->lock
);
1576 wake_up (&ep
->wait
);
1579 /* break link to dcache */
1583 inode_unlock(parent
);
1585 spin_lock_irq (&dev
->lock
);
1587 spin_unlock_irq (&dev
->lock
);
1591 static struct dentry
*
1592 gadgetfs_create_file (struct super_block
*sb
, char const *name
,
1593 void *data
, const struct file_operations
*fops
);
1595 static int activate_ep_files (struct dev_data
*dev
)
1598 struct ep_data
*data
;
1600 gadget_for_each_ep (ep
, dev
->gadget
) {
1602 data
= kzalloc(sizeof(*data
), GFP_KERNEL
);
1605 data
->state
= STATE_EP_DISABLED
;
1606 mutex_init(&data
->lock
);
1607 init_waitqueue_head (&data
->wait
);
1609 strncpy (data
->name
, ep
->name
, sizeof (data
->name
) - 1);
1610 refcount_set (&data
->count
, 1);
1615 ep
->driver_data
= data
;
1617 data
->req
= usb_ep_alloc_request (ep
, GFP_KERNEL
);
1621 data
->dentry
= gadgetfs_create_file (dev
->sb
, data
->name
,
1622 data
, &ep_io_operations
);
1625 list_add_tail (&data
->epfiles
, &dev
->epfiles
);
1630 usb_ep_free_request (ep
, data
->req
);
1635 DBG (dev
, "%s enomem\n", __func__
);
1636 destroy_ep_files (dev
);
1641 gadgetfs_unbind (struct usb_gadget
*gadget
)
1643 struct dev_data
*dev
= get_gadget_data (gadget
);
1645 DBG (dev
, "%s\n", __func__
);
1647 spin_lock_irq (&dev
->lock
);
1648 dev
->state
= STATE_DEV_UNBOUND
;
1649 while (dev
->udc_usage
> 0) {
1650 spin_unlock_irq(&dev
->lock
);
1651 usleep_range(1000, 2000);
1652 spin_lock_irq(&dev
->lock
);
1654 spin_unlock_irq (&dev
->lock
);
1656 destroy_ep_files (dev
);
1657 gadget
->ep0
->driver_data
= NULL
;
1658 set_gadget_data (gadget
, NULL
);
1660 /* we've already been disconnected ... no i/o is active */
1662 usb_ep_free_request (gadget
->ep0
, dev
->req
);
1663 DBG (dev
, "%s done\n", __func__
);
1667 static struct dev_data
*the_device
;
1669 static int gadgetfs_bind(struct usb_gadget
*gadget
,
1670 struct usb_gadget_driver
*driver
)
1672 struct dev_data
*dev
= the_device
;
1676 if (0 != strcmp (CHIP
, gadget
->name
)) {
1677 pr_err("%s expected %s controller not %s\n",
1678 shortname
, CHIP
, gadget
->name
);
1682 set_gadget_data (gadget
, dev
);
1683 dev
->gadget
= gadget
;
1684 gadget
->ep0
->driver_data
= dev
;
1686 /* preallocate control response and buffer */
1687 dev
->req
= usb_ep_alloc_request (gadget
->ep0
, GFP_KERNEL
);
1690 dev
->req
->context
= NULL
;
1691 dev
->req
->complete
= epio_complete
;
1693 if (activate_ep_files (dev
) < 0)
1696 INFO (dev
, "bound to %s driver\n", gadget
->name
);
1697 spin_lock_irq(&dev
->lock
);
1698 dev
->state
= STATE_DEV_UNCONNECTED
;
1699 spin_unlock_irq(&dev
->lock
);
1704 gadgetfs_unbind (gadget
);
1709 gadgetfs_disconnect (struct usb_gadget
*gadget
)
1711 struct dev_data
*dev
= get_gadget_data (gadget
);
1712 unsigned long flags
;
1714 spin_lock_irqsave (&dev
->lock
, flags
);
1715 if (dev
->state
== STATE_DEV_UNCONNECTED
)
1717 dev
->state
= STATE_DEV_UNCONNECTED
;
1719 INFO (dev
, "disconnected\n");
1720 next_event (dev
, GADGETFS_DISCONNECT
);
1723 spin_unlock_irqrestore (&dev
->lock
, flags
);
1727 gadgetfs_suspend (struct usb_gadget
*gadget
)
1729 struct dev_data
*dev
= get_gadget_data (gadget
);
1730 unsigned long flags
;
1732 INFO (dev
, "suspended from state %d\n", dev
->state
);
1733 spin_lock_irqsave(&dev
->lock
, flags
);
1734 switch (dev
->state
) {
1735 case STATE_DEV_SETUP
: // VERY odd... host died??
1736 case STATE_DEV_CONNECTED
:
1737 case STATE_DEV_UNCONNECTED
:
1738 next_event (dev
, GADGETFS_SUSPEND
);
1744 spin_unlock_irqrestore(&dev
->lock
, flags
);
1747 static struct usb_gadget_driver gadgetfs_driver
= {
1748 .function
= (char *) driver_desc
,
1749 .bind
= gadgetfs_bind
,
1750 .unbind
= gadgetfs_unbind
,
1751 .setup
= gadgetfs_setup
,
1752 .reset
= gadgetfs_disconnect
,
1753 .disconnect
= gadgetfs_disconnect
,
1754 .suspend
= gadgetfs_suspend
,
1757 .name
= (char *) shortname
,
1761 /*----------------------------------------------------------------------*/
1762 /* DEVICE INITIALIZATION
1764 * fd = open ("/dev/gadget/$CHIP", O_RDWR)
1765 * status = write (fd, descriptors, sizeof descriptors)
1767 * That write establishes the device configuration, so the kernel can
1768 * bind to the controller ... guaranteeing it can handle enumeration
1769 * at all necessary speeds. Descriptor order is:
1771 * . message tag (u32, host order) ... for now, must be zero; it
1772 * would change to support features like multi-config devices
1773 * . full/low speed config ... all wTotalLength bytes (with interface,
1774 * class, altsetting, endpoint, and other descriptors)
1775 * . high speed config ... all descriptors, for high speed operation;
1776 * this one's optional except for high-speed hardware
1777 * . device descriptor
1779 * Endpoints are not yet enabled. Drivers must wait until device
1780 * configuration and interface altsetting changes create
1781 * the need to configure (or unconfigure) them.
1783 * After initialization, the device stays active for as long as that
1784 * $CHIP file is open. Events must then be read from that descriptor,
1785 * such as configuration notifications.
1788 static int is_valid_config(struct usb_config_descriptor
*config
,
1791 return config
->bDescriptorType
== USB_DT_CONFIG
1792 && config
->bLength
== USB_DT_CONFIG_SIZE
1793 && total
>= USB_DT_CONFIG_SIZE
1794 && config
->bConfigurationValue
!= 0
1795 && (config
->bmAttributes
& USB_CONFIG_ATT_ONE
) != 0
1796 && (config
->bmAttributes
& USB_CONFIG_ATT_WAKEUP
) == 0;
1797 /* FIXME if gadget->is_otg, _must_ include an otg descriptor */
1798 /* FIXME check lengths: walk to end */
1802 dev_config (struct file
*fd
, const char __user
*buf
, size_t len
, loff_t
*ptr
)
1804 struct dev_data
*dev
= fd
->private_data
;
1805 ssize_t value
= len
, length
= len
;
1810 spin_lock_irq(&dev
->lock
);
1811 if (dev
->state
> STATE_DEV_OPENED
) {
1812 value
= ep0_write(fd
, buf
, len
, ptr
);
1813 spin_unlock_irq(&dev
->lock
);
1816 spin_unlock_irq(&dev
->lock
);
1818 if ((len
< (USB_DT_CONFIG_SIZE
+ USB_DT_DEVICE_SIZE
+ 4)) ||
1819 (len
> PAGE_SIZE
* 4))
1822 /* we might need to change message format someday */
1823 if (copy_from_user (&tag
, buf
, 4))
1830 kbuf
= memdup_user(buf
, length
);
1832 return PTR_ERR(kbuf
);
1834 spin_lock_irq (&dev
->lock
);
1837 spin_unlock_irq(&dev
->lock
);
1843 /* full or low speed config */
1844 dev
->config
= (void *) kbuf
;
1845 total
= le16_to_cpu(dev
->config
->wTotalLength
);
1846 if (!is_valid_config(dev
->config
, total
) ||
1847 total
> length
- USB_DT_DEVICE_SIZE
)
1852 /* optional high speed config */
1853 if (kbuf
[1] == USB_DT_CONFIG
) {
1854 dev
->hs_config
= (void *) kbuf
;
1855 total
= le16_to_cpu(dev
->hs_config
->wTotalLength
);
1856 if (!is_valid_config(dev
->hs_config
, total
) ||
1857 total
> length
- USB_DT_DEVICE_SIZE
)
1862 dev
->hs_config
= NULL
;
1865 /* could support multiple configs, using another encoding! */
1867 /* device descriptor (tweaked for paranoia) */
1868 if (length
!= USB_DT_DEVICE_SIZE
)
1870 dev
->dev
= (void *)kbuf
;
1871 if (dev
->dev
->bLength
!= USB_DT_DEVICE_SIZE
1872 || dev
->dev
->bDescriptorType
!= USB_DT_DEVICE
1873 || dev
->dev
->bNumConfigurations
!= 1)
1875 dev
->dev
->bcdUSB
= cpu_to_le16 (0x0200);
1877 /* triggers gadgetfs_bind(); then we can enumerate. */
1878 spin_unlock_irq (&dev
->lock
);
1880 gadgetfs_driver
.max_speed
= USB_SPEED_HIGH
;
1882 gadgetfs_driver
.max_speed
= USB_SPEED_FULL
;
1884 value
= usb_gadget_probe_driver(&gadgetfs_driver
);
1889 /* at this point "good" hardware has for the first time
1890 * let the USB the host see us. alternatively, if users
1891 * unplug/replug that will clear all the error state.
1893 * note: everything running before here was guaranteed
1894 * to choke driver model style diagnostics. from here
1895 * on, they can work ... except in cleanup paths that
1896 * kick in after the ep0 descriptor is closed.
1899 dev
->gadget_registered
= true;
1904 spin_unlock_irq (&dev
->lock
);
1905 pr_debug ("%s: %s fail %zd, %p\n", shortname
, __func__
, value
, dev
);
1912 dev_open (struct inode
*inode
, struct file
*fd
)
1914 struct dev_data
*dev
= inode
->i_private
;
1917 spin_lock_irq(&dev
->lock
);
1918 if (dev
->state
== STATE_DEV_DISABLED
) {
1920 dev
->state
= STATE_DEV_OPENED
;
1921 fd
->private_data
= dev
;
1925 spin_unlock_irq(&dev
->lock
);
1929 static const struct file_operations ep0_operations
= {
1930 .llseek
= no_llseek
,
1934 .write
= dev_config
,
1935 .fasync
= ep0_fasync
,
1937 .unlocked_ioctl
= dev_ioctl
,
1938 .release
= dev_release
,
1941 /*----------------------------------------------------------------------*/
1943 /* FILESYSTEM AND SUPERBLOCK OPERATIONS
1945 * Mounting the filesystem creates a controller file, used first for
1946 * device configuration then later for event monitoring.
1950 /* FIXME PAM etc could set this security policy without mount options
1951 * if epfiles inherited ownership and permissons from ep0 ...
1954 static unsigned default_uid
;
1955 static unsigned default_gid
;
1956 static unsigned default_perm
= S_IRUSR
| S_IWUSR
;
1958 module_param (default_uid
, uint
, 0644);
1959 module_param (default_gid
, uint
, 0644);
1960 module_param (default_perm
, uint
, 0644);
1963 static struct inode
*
1964 gadgetfs_make_inode (struct super_block
*sb
,
1965 void *data
, const struct file_operations
*fops
,
1968 struct inode
*inode
= new_inode (sb
);
1971 inode
->i_ino
= get_next_ino();
1972 inode
->i_mode
= mode
;
1973 inode
->i_uid
= make_kuid(&init_user_ns
, default_uid
);
1974 inode
->i_gid
= make_kgid(&init_user_ns
, default_gid
);
1975 inode
->i_atime
= inode
->i_mtime
= inode
->i_ctime
1976 = current_time(inode
);
1977 inode
->i_private
= data
;
1978 inode
->i_fop
= fops
;
1983 /* creates in fs root directory, so non-renamable and non-linkable.
1984 * so inode and dentry are paired, until device reconfig.
1986 static struct dentry
*
1987 gadgetfs_create_file (struct super_block
*sb
, char const *name
,
1988 void *data
, const struct file_operations
*fops
)
1990 struct dentry
*dentry
;
1991 struct inode
*inode
;
1993 dentry
= d_alloc_name(sb
->s_root
, name
);
1997 inode
= gadgetfs_make_inode (sb
, data
, fops
,
1998 S_IFREG
| (default_perm
& S_IRWXUGO
));
2003 d_add (dentry
, inode
);
2007 static const struct super_operations gadget_fs_operations
= {
2008 .statfs
= simple_statfs
,
2009 .drop_inode
= generic_delete_inode
,
2013 gadgetfs_fill_super (struct super_block
*sb
, void *opts
, int silent
)
2015 struct inode
*inode
;
2016 struct dev_data
*dev
;
2021 CHIP
= usb_get_gadget_udc_name();
2026 sb
->s_blocksize
= PAGE_SIZE
;
2027 sb
->s_blocksize_bits
= PAGE_SHIFT
;
2028 sb
->s_magic
= GADGETFS_MAGIC
;
2029 sb
->s_op
= &gadget_fs_operations
;
2030 sb
->s_time_gran
= 1;
2033 inode
= gadgetfs_make_inode (sb
,
2034 NULL
, &simple_dir_operations
,
2035 S_IFDIR
| S_IRUGO
| S_IXUGO
);
2038 inode
->i_op
= &simple_dir_inode_operations
;
2039 if (!(sb
->s_root
= d_make_root (inode
)))
2042 /* the ep0 file is named after the controller we expect;
2043 * user mode code can use it for sanity checks, like we do.
2050 dev
->dentry
= gadgetfs_create_file(sb
, CHIP
, dev
, &ep0_operations
);
2056 /* other endpoint files are available after hardware setup,
2057 * from binding to a controller.
2066 /* "mount -t gadgetfs path /dev/gadget" ends up here */
2067 static struct dentry
*
2068 gadgetfs_mount (struct file_system_type
*t
, int flags
,
2069 const char *path
, void *opts
)
2071 return mount_single (t
, flags
, opts
, gadgetfs_fill_super
);
2075 gadgetfs_kill_sb (struct super_block
*sb
)
2077 kill_litter_super (sb
);
2079 put_dev (the_device
);
2086 /*----------------------------------------------------------------------*/
2088 static struct file_system_type gadgetfs_type
= {
2089 .owner
= THIS_MODULE
,
2091 .mount
= gadgetfs_mount
,
2092 .kill_sb
= gadgetfs_kill_sb
,
2094 MODULE_ALIAS_FS("gadgetfs");
2096 /*----------------------------------------------------------------------*/
2098 static int __init
init (void)
2102 status
= register_filesystem (&gadgetfs_type
);
2104 pr_info ("%s: %s, version " DRIVER_VERSION
"\n",
2105 shortname
, driver_desc
);
2110 static void __exit
cleanup (void)
2112 pr_debug ("unregister %s\n", shortname
);
2113 unregister_filesystem (&gadgetfs_type
);
2115 module_exit (cleanup
);