2 * inode.c -- user mode filesystem api for usb gadget controllers
4 * Copyright (C) 2003-2004 David Brownell
5 * Copyright (C) 2003 Agilent Technologies
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 2 of the License, or
10 * (at your option) any later version.
14 /* #define VERBOSE_DEBUG */
16 #include <linux/init.h>
17 #include <linux/module.h>
19 #include <linux/pagemap.h>
20 #include <linux/uts.h>
21 #include <linux/wait.h>
22 #include <linux/compiler.h>
23 #include <asm/uaccess.h>
24 #include <linux/sched.h>
25 #include <linux/slab.h>
26 #include <linux/poll.h>
27 #include <linux/mmu_context.h>
28 #include <linux/aio.h>
30 #include <linux/device.h>
31 #include <linux/moduleparam.h>
33 #include <linux/usb/gadgetfs.h>
34 #include <linux/usb/gadget.h>
38 * The gadgetfs API maps each endpoint to a file descriptor so that you
39 * can use standard synchronous read/write calls for I/O. There's some
40 * O_NONBLOCK and O_ASYNC/FASYNC style i/o support. Example usermode
41 * drivers show how this works in practice. You can also use AIO to
42 * eliminate I/O gaps between requests, to help when streaming data.
44 * Key parts that must be USB-specific are protocols defining how the
45 * read/write operations relate to the hardware state machines. There
46 * are two types of files. One type is for the device, implementing ep0.
47 * The other type is for each IN or OUT endpoint. In both cases, the
48 * user mode driver must configure the hardware before using it.
50 * - First, dev_config() is called when /dev/gadget/$CHIP is configured
51 * (by writing configuration and device descriptors). Afterwards it
52 * may serve as a source of device events, used to handle all control
53 * requests other than basic enumeration.
55 * - Then, after a SET_CONFIGURATION control request, ep_config() is
56 * called when each /dev/gadget/ep* file is configured (by writing
57 * endpoint descriptors). Afterwards these files are used to write()
58 * IN data or to read() OUT data. To halt the endpoint, a "wrong
59 * direction" request is issued (like reading an IN endpoint).
61 * Unlike "usbfs" the only ioctl()s are for things that are rare, and maybe
62 * not possible on all hardware. For example, precise fault handling with
63 * respect to data left in endpoint fifos after aborted operations; or
64 * selective clearing of endpoint halts, to implement SET_INTERFACE.
67 #define DRIVER_DESC "USB Gadget filesystem"
68 #define DRIVER_VERSION "24 Aug 2004"
70 static const char driver_desc
[] = DRIVER_DESC
;
71 static const char shortname
[] = "gadgetfs";
73 MODULE_DESCRIPTION (DRIVER_DESC
);
74 MODULE_AUTHOR ("David Brownell");
75 MODULE_LICENSE ("GPL");
78 /*----------------------------------------------------------------------*/
80 #define GADGETFS_MAGIC 0xaee71ee7
82 /* /dev/gadget/$CHIP represents ep0 and the whole device */
84 /* DISBLED is the initial state.
86 STATE_DEV_DISABLED
= 0,
88 /* Only one open() of /dev/gadget/$CHIP; only one file tracks
89 * ep0/device i/o modes and binding to the controller. Driver
90 * must always write descriptors to initialize the device, then
91 * the device becomes UNCONNECTED until enumeration.
95 /* From then on, ep0 fd is in either of two basic modes:
96 * - (UN)CONNECTED: read usb_gadgetfs_event(s) from it
97 * - SETUP: read/write will transfer control data and succeed;
98 * or if "wrong direction", performs protocol stall
100 STATE_DEV_UNCONNECTED
,
104 /* UNBOUND means the driver closed ep0, so the device won't be
105 * accessible again (DEV_DISABLED) until all fds are closed.
110 /* enough for the whole queue: most events invalidate others */
116 enum ep0_state state
; /* P: lock */
117 struct usb_gadgetfs_event event
[N_EVENT
];
119 struct fasync_struct
*fasync
;
122 /* drivers reading ep0 MUST handle control requests (SETUP)
123 * reported that way; else the host will time out.
125 unsigned usermode_setup
: 1,
131 unsigned setup_wLength
;
133 /* the rest is basically write-once */
134 struct usb_config_descriptor
*config
, *hs_config
;
135 struct usb_device_descriptor
*dev
;
136 struct usb_request
*req
;
137 struct usb_gadget
*gadget
;
138 struct list_head epfiles
;
140 wait_queue_head_t wait
;
141 struct super_block
*sb
;
142 struct dentry
*dentry
;
144 /* except this scratch i/o buffer for ep0 */
148 static inline void get_dev (struct dev_data
*data
)
150 atomic_inc (&data
->count
);
153 static void put_dev (struct dev_data
*data
)
155 if (likely (!atomic_dec_and_test (&data
->count
)))
157 /* needs no more cleanup */
158 BUG_ON (waitqueue_active (&data
->wait
));
162 static struct dev_data
*dev_new (void)
164 struct dev_data
*dev
;
166 dev
= kzalloc(sizeof(*dev
), GFP_KERNEL
);
169 dev
->state
= STATE_DEV_DISABLED
;
170 atomic_set (&dev
->count
, 1);
171 spin_lock_init (&dev
->lock
);
172 INIT_LIST_HEAD (&dev
->epfiles
);
173 init_waitqueue_head (&dev
->wait
);
177 /*----------------------------------------------------------------------*/
179 /* other /dev/gadget/$ENDPOINT files represent endpoints */
181 STATE_EP_DISABLED
= 0,
191 struct dev_data
*dev
;
192 /* must hold dev->lock before accessing ep or req */
194 struct usb_request
*req
;
197 struct usb_endpoint_descriptor desc
, hs_desc
;
198 struct list_head epfiles
;
199 wait_queue_head_t wait
;
200 struct dentry
*dentry
;
203 static inline void get_ep (struct ep_data
*data
)
205 atomic_inc (&data
->count
);
208 static void put_ep (struct ep_data
*data
)
210 if (likely (!atomic_dec_and_test (&data
->count
)))
213 /* needs no more cleanup */
214 BUG_ON (!list_empty (&data
->epfiles
));
215 BUG_ON (waitqueue_active (&data
->wait
));
219 /*----------------------------------------------------------------------*/
221 /* most "how to use the hardware" policy choices are in userspace:
222 * mapping endpoint roles (which the driver needs) to the capabilities
223 * which the usb controller has. most of those capabilities are exposed
224 * implicitly, starting with the driver name and then endpoint names.
227 static const char *CHIP
;
229 /*----------------------------------------------------------------------*/
231 /* NOTE: don't use dev_printk calls before binding to the gadget
232 * at the end of ep0 configuration, or after unbind.
235 /* too wordy: dev_printk(level , &(d)->gadget->dev , fmt , ## args) */
236 #define xprintk(d,level,fmt,args...) \
237 printk(level "%s: " fmt , shortname , ## args)
240 #define DBG(dev,fmt,args...) \
241 xprintk(dev , KERN_DEBUG , fmt , ## args)
243 #define DBG(dev,fmt,args...) \
250 #define VDEBUG(dev,fmt,args...) \
254 #define ERROR(dev,fmt,args...) \
255 xprintk(dev , KERN_ERR , fmt , ## args)
256 #define INFO(dev,fmt,args...) \
257 xprintk(dev , KERN_INFO , fmt , ## args)
260 /*----------------------------------------------------------------------*/
262 /* SYNCHRONOUS ENDPOINT OPERATIONS (bulk/intr/iso)
264 * After opening, configure non-control endpoints. Then use normal
265 * stream read() and write() requests; and maybe ioctl() to get more
266 * precise FIFO status when recovering from cancellation.
269 static void epio_complete (struct usb_ep
*ep
, struct usb_request
*req
)
271 struct ep_data
*epdata
= ep
->driver_data
;
276 epdata
->status
= req
->status
;
278 epdata
->status
= req
->actual
;
279 complete ((struct completion
*)req
->context
);
282 /* tasklock endpoint, returning when it's connected.
283 * still need dev->lock to use epdata->ep.
286 get_ready_ep (unsigned f_flags
, struct ep_data
*epdata
)
290 if (f_flags
& O_NONBLOCK
) {
291 if (!mutex_trylock(&epdata
->lock
))
293 if (epdata
->state
!= STATE_EP_ENABLED
) {
294 mutex_unlock(&epdata
->lock
);
302 val
= mutex_lock_interruptible(&epdata
->lock
);
306 switch (epdata
->state
) {
307 case STATE_EP_ENABLED
:
309 // case STATE_EP_DISABLED: /* "can't happen" */
310 // case STATE_EP_READY: /* "can't happen" */
311 default: /* error! */
312 pr_debug ("%s: ep %p not available, state %d\n",
313 shortname
, epdata
, epdata
->state
);
315 case STATE_EP_UNBOUND
: /* clean disconnect */
317 mutex_unlock(&epdata
->lock
);
323 ep_io (struct ep_data
*epdata
, void *buf
, unsigned len
)
325 DECLARE_COMPLETION_ONSTACK (done
);
328 spin_lock_irq (&epdata
->dev
->lock
);
329 if (likely (epdata
->ep
!= NULL
)) {
330 struct usb_request
*req
= epdata
->req
;
332 req
->context
= &done
;
333 req
->complete
= epio_complete
;
336 value
= usb_ep_queue (epdata
->ep
, req
, GFP_ATOMIC
);
339 spin_unlock_irq (&epdata
->dev
->lock
);
341 if (likely (value
== 0)) {
342 value
= wait_event_interruptible (done
.wait
, done
.done
);
344 spin_lock_irq (&epdata
->dev
->lock
);
345 if (likely (epdata
->ep
!= NULL
)) {
346 DBG (epdata
->dev
, "%s i/o interrupted\n",
348 usb_ep_dequeue (epdata
->ep
, epdata
->req
);
349 spin_unlock_irq (&epdata
->dev
->lock
);
351 wait_event (done
.wait
, done
.done
);
352 if (epdata
->status
== -ECONNRESET
)
353 epdata
->status
= -EINTR
;
355 spin_unlock_irq (&epdata
->dev
->lock
);
357 DBG (epdata
->dev
, "endpoint gone\n");
358 epdata
->status
= -ENODEV
;
361 return epdata
->status
;
367 /* handle a synchronous OUT bulk/intr/iso transfer */
369 ep_read (struct file
*fd
, char __user
*buf
, size_t len
, loff_t
*ptr
)
371 struct ep_data
*data
= fd
->private_data
;
375 if ((value
= get_ready_ep (fd
->f_flags
, data
)) < 0)
378 /* halt any endpoint by doing a "wrong direction" i/o call */
379 if (usb_endpoint_dir_in(&data
->desc
)) {
380 if (usb_endpoint_xfer_isoc(&data
->desc
)) {
381 mutex_unlock(&data
->lock
);
384 DBG (data
->dev
, "%s halt\n", data
->name
);
385 spin_lock_irq (&data
->dev
->lock
);
386 if (likely (data
->ep
!= NULL
))
387 usb_ep_set_halt (data
->ep
);
388 spin_unlock_irq (&data
->dev
->lock
);
389 mutex_unlock(&data
->lock
);
393 /* FIXME readahead for O_NONBLOCK and poll(); careful with ZLPs */
396 kbuf
= kmalloc (len
, GFP_KERNEL
);
397 if (unlikely (!kbuf
))
400 value
= ep_io (data
, kbuf
, len
);
401 VDEBUG (data
->dev
, "%s read %zu OUT, status %d\n",
402 data
->name
, len
, (int) value
);
403 if (value
>= 0 && copy_to_user (buf
, kbuf
, value
))
407 mutex_unlock(&data
->lock
);
412 /* handle a synchronous IN bulk/intr/iso transfer */
414 ep_write (struct file
*fd
, const char __user
*buf
, size_t len
, loff_t
*ptr
)
416 struct ep_data
*data
= fd
->private_data
;
420 if ((value
= get_ready_ep (fd
->f_flags
, data
)) < 0)
423 /* halt any endpoint by doing a "wrong direction" i/o call */
424 if (!usb_endpoint_dir_in(&data
->desc
)) {
425 if (usb_endpoint_xfer_isoc(&data
->desc
)) {
426 mutex_unlock(&data
->lock
);
429 DBG (data
->dev
, "%s halt\n", data
->name
);
430 spin_lock_irq (&data
->dev
->lock
);
431 if (likely (data
->ep
!= NULL
))
432 usb_ep_set_halt (data
->ep
);
433 spin_unlock_irq (&data
->dev
->lock
);
434 mutex_unlock(&data
->lock
);
438 /* FIXME writebehind for O_NONBLOCK and poll(), qlen = 1 */
441 kbuf
= memdup_user(buf
, len
);
443 value
= PTR_ERR(kbuf
);
448 value
= ep_io (data
, kbuf
, len
);
449 VDEBUG (data
->dev
, "%s write %zu IN, status %d\n",
450 data
->name
, len
, (int) value
);
452 mutex_unlock(&data
->lock
);
458 ep_release (struct inode
*inode
, struct file
*fd
)
460 struct ep_data
*data
= fd
->private_data
;
463 value
= mutex_lock_interruptible(&data
->lock
);
467 /* clean up if this can be reopened */
468 if (data
->state
!= STATE_EP_UNBOUND
) {
469 data
->state
= STATE_EP_DISABLED
;
470 data
->desc
.bDescriptorType
= 0;
471 data
->hs_desc
.bDescriptorType
= 0;
472 usb_ep_disable(data
->ep
);
474 mutex_unlock(&data
->lock
);
479 static long ep_ioctl(struct file
*fd
, unsigned code
, unsigned long value
)
481 struct ep_data
*data
= fd
->private_data
;
484 if ((status
= get_ready_ep (fd
->f_flags
, data
)) < 0)
487 spin_lock_irq (&data
->dev
->lock
);
488 if (likely (data
->ep
!= NULL
)) {
490 case GADGETFS_FIFO_STATUS
:
491 status
= usb_ep_fifo_status (data
->ep
);
493 case GADGETFS_FIFO_FLUSH
:
494 usb_ep_fifo_flush (data
->ep
);
496 case GADGETFS_CLEAR_HALT
:
497 status
= usb_ep_clear_halt (data
->ep
);
504 spin_unlock_irq (&data
->dev
->lock
);
505 mutex_unlock(&data
->lock
);
509 /*----------------------------------------------------------------------*/
511 /* ASYNCHRONOUS ENDPOINT I/O OPERATIONS (bulk/intr/iso) */
514 struct usb_request
*req
;
515 struct ep_data
*epdata
;
517 struct mm_struct
*mm
;
518 struct work_struct work
;
520 const struct iovec
*iv
;
521 unsigned long nr_segs
;
525 static int ep_aio_cancel(struct kiocb
*iocb
)
527 struct kiocb_priv
*priv
= iocb
->private;
528 struct ep_data
*epdata
;
532 epdata
= priv
->epdata
;
533 // spin_lock(&epdata->dev->lock);
534 if (likely(epdata
&& epdata
->ep
&& priv
->req
))
535 value
= usb_ep_dequeue (epdata
->ep
, priv
->req
);
538 // spin_unlock(&epdata->dev->lock);
544 static ssize_t
ep_copy_to_user(struct kiocb_priv
*priv
)
550 /* copy stuff into user buffers */
551 total
= priv
->actual
;
554 for (i
=0; i
< priv
->nr_segs
; i
++) {
555 ssize_t
this = min((ssize_t
)(priv
->iv
[i
].iov_len
), total
);
557 if (copy_to_user(priv
->iv
[i
].iov_base
, to_copy
, this)) {
573 static void ep_user_copy_worker(struct work_struct
*work
)
575 struct kiocb_priv
*priv
= container_of(work
, struct kiocb_priv
, work
);
576 struct mm_struct
*mm
= priv
->mm
;
577 struct kiocb
*iocb
= priv
->iocb
;
581 ret
= ep_copy_to_user(priv
);
584 /* completing the iocb can drop the ctx and mm, don't touch mm after */
585 aio_complete(iocb
, ret
, ret
);
591 static void ep_aio_complete(struct usb_ep
*ep
, struct usb_request
*req
)
593 struct kiocb
*iocb
= req
->context
;
594 struct kiocb_priv
*priv
= iocb
->private;
595 struct ep_data
*epdata
= priv
->epdata
;
597 /* lock against disconnect (and ideally, cancel) */
598 spin_lock(&epdata
->dev
->lock
);
602 /* if this was a write or a read returning no data then we
603 * don't need to copy anything to userspace, so we can
604 * complete the aio request immediately.
606 if (priv
->iv
== NULL
|| unlikely(req
->actual
== 0)) {
609 iocb
->private = NULL
;
610 /* aio_complete() reports bytes-transferred _and_ faults */
611 aio_complete(iocb
, req
->actual
? req
->actual
: req
->status
,
614 /* ep_copy_to_user() won't report both; we hide some faults */
615 if (unlikely(0 != req
->status
))
616 DBG(epdata
->dev
, "%s fault %d len %d\n",
617 ep
->name
, req
->status
, req
->actual
);
619 priv
->buf
= req
->buf
;
620 priv
->actual
= req
->actual
;
621 schedule_work(&priv
->work
);
623 spin_unlock(&epdata
->dev
->lock
);
625 usb_ep_free_request(ep
, req
);
634 struct ep_data
*epdata
,
635 const struct iovec
*iv
,
636 unsigned long nr_segs
639 struct kiocb_priv
*priv
;
640 struct usb_request
*req
;
643 priv
= kmalloc(sizeof *priv
, GFP_KERNEL
);
650 iocb
->private = priv
;
653 priv
->nr_segs
= nr_segs
;
654 INIT_WORK(&priv
->work
, ep_user_copy_worker
);
656 value
= get_ready_ep(iocb
->ki_filp
->f_flags
, epdata
);
657 if (unlikely(value
< 0)) {
662 kiocb_set_cancel_fn(iocb
, ep_aio_cancel
);
664 priv
->epdata
= epdata
;
666 priv
->mm
= current
->mm
; /* mm teardown waits for iocbs in exit_aio() */
668 /* each kiocb is coupled to one usb_request, but we can't
669 * allocate or submit those if the host disconnected.
671 spin_lock_irq(&epdata
->dev
->lock
);
672 if (likely(epdata
->ep
)) {
673 req
= usb_ep_alloc_request(epdata
->ep
, GFP_ATOMIC
);
678 req
->complete
= ep_aio_complete
;
680 value
= usb_ep_queue(epdata
->ep
, req
, GFP_ATOMIC
);
681 if (unlikely(0 != value
))
682 usb_ep_free_request(epdata
->ep
, req
);
687 spin_unlock_irq(&epdata
->dev
->lock
);
689 mutex_unlock(&epdata
->lock
);
691 if (unlikely(value
)) {
695 value
= -EIOCBQUEUED
;
700 ep_aio_read(struct kiocb
*iocb
, const struct iovec
*iov
,
701 unsigned long nr_segs
, loff_t o
)
703 struct ep_data
*epdata
= iocb
->ki_filp
->private_data
;
706 if (unlikely(usb_endpoint_dir_in(&epdata
->desc
)))
709 buf
= kmalloc(iocb
->ki_nbytes
, GFP_KERNEL
);
713 return ep_aio_rwtail(iocb
, buf
, iocb
->ki_nbytes
, epdata
, iov
, nr_segs
);
717 ep_aio_write(struct kiocb
*iocb
, const struct iovec
*iov
,
718 unsigned long nr_segs
, loff_t o
)
720 struct ep_data
*epdata
= iocb
->ki_filp
->private_data
;
725 if (unlikely(!usb_endpoint_dir_in(&epdata
->desc
)))
728 buf
= kmalloc(iocb
->ki_nbytes
, GFP_KERNEL
);
732 for (i
=0; i
< nr_segs
; i
++) {
733 if (unlikely(copy_from_user(&buf
[len
], iov
[i
].iov_base
,
734 iov
[i
].iov_len
) != 0)) {
738 len
+= iov
[i
].iov_len
;
740 return ep_aio_rwtail(iocb
, buf
, len
, epdata
, NULL
, 0);
743 /*----------------------------------------------------------------------*/
745 /* used after endpoint configuration */
746 static const struct file_operations ep_io_operations
= {
747 .owner
= THIS_MODULE
,
752 .unlocked_ioctl
= ep_ioctl
,
753 .release
= ep_release
,
755 .aio_read
= ep_aio_read
,
756 .aio_write
= ep_aio_write
,
759 /* ENDPOINT INITIALIZATION
761 * fd = open ("/dev/gadget/$ENDPOINT", O_RDWR)
762 * status = write (fd, descriptors, sizeof descriptors)
764 * That write establishes the endpoint configuration, configuring
765 * the controller to process bulk, interrupt, or isochronous transfers
766 * at the right maxpacket size, and so on.
768 * The descriptors are message type 1, identified by a host order u32
769 * at the beginning of what's written. Descriptor order is: full/low
770 * speed descriptor, then optional high speed descriptor.
773 ep_config (struct file
*fd
, const char __user
*buf
, size_t len
, loff_t
*ptr
)
775 struct ep_data
*data
= fd
->private_data
;
778 int value
, length
= len
;
780 value
= mutex_lock_interruptible(&data
->lock
);
784 if (data
->state
!= STATE_EP_READY
) {
790 if (len
< USB_DT_ENDPOINT_SIZE
+ 4)
793 /* we might need to change message format someday */
794 if (copy_from_user (&tag
, buf
, 4)) {
798 DBG(data
->dev
, "config %s, bad tag %d\n", data
->name
, tag
);
804 /* NOTE: audio endpoint extensions not accepted here;
805 * just don't include the extra bytes.
808 /* full/low speed descriptor, then high speed */
809 if (copy_from_user (&data
->desc
, buf
, USB_DT_ENDPOINT_SIZE
)) {
812 if (data
->desc
.bLength
!= USB_DT_ENDPOINT_SIZE
813 || data
->desc
.bDescriptorType
!= USB_DT_ENDPOINT
)
815 if (len
!= USB_DT_ENDPOINT_SIZE
) {
816 if (len
!= 2 * USB_DT_ENDPOINT_SIZE
)
818 if (copy_from_user (&data
->hs_desc
, buf
+ USB_DT_ENDPOINT_SIZE
,
819 USB_DT_ENDPOINT_SIZE
)) {
822 if (data
->hs_desc
.bLength
!= USB_DT_ENDPOINT_SIZE
823 || data
->hs_desc
.bDescriptorType
824 != USB_DT_ENDPOINT
) {
825 DBG(data
->dev
, "config %s, bad hs length or type\n",
831 spin_lock_irq (&data
->dev
->lock
);
832 if (data
->dev
->state
== STATE_DEV_UNBOUND
) {
835 } else if ((ep
= data
->ep
) == NULL
) {
839 switch (data
->dev
->gadget
->speed
) {
842 ep
->desc
= &data
->desc
;
843 value
= usb_ep_enable(ep
);
845 data
->state
= STATE_EP_ENABLED
;
848 /* fails if caller didn't provide that descriptor... */
849 ep
->desc
= &data
->hs_desc
;
850 value
= usb_ep_enable(ep
);
852 data
->state
= STATE_EP_ENABLED
;
855 DBG(data
->dev
, "unconnected, %s init abandoned\n",
860 fd
->f_op
= &ep_io_operations
;
864 spin_unlock_irq (&data
->dev
->lock
);
867 data
->desc
.bDescriptorType
= 0;
868 data
->hs_desc
.bDescriptorType
= 0;
870 mutex_unlock(&data
->lock
);
881 ep_open (struct inode
*inode
, struct file
*fd
)
883 struct ep_data
*data
= inode
->i_private
;
886 if (mutex_lock_interruptible(&data
->lock
) != 0)
888 spin_lock_irq (&data
->dev
->lock
);
889 if (data
->dev
->state
== STATE_DEV_UNBOUND
)
891 else if (data
->state
== STATE_EP_DISABLED
) {
893 data
->state
= STATE_EP_READY
;
895 fd
->private_data
= data
;
896 VDEBUG (data
->dev
, "%s ready\n", data
->name
);
898 DBG (data
->dev
, "%s state %d\n",
899 data
->name
, data
->state
);
900 spin_unlock_irq (&data
->dev
->lock
);
901 mutex_unlock(&data
->lock
);
905 /* used before endpoint configuration */
906 static const struct file_operations ep_config_operations
= {
911 .release
= ep_release
,
914 /*----------------------------------------------------------------------*/
916 /* EP0 IMPLEMENTATION can be partly in userspace.
918 * Drivers that use this facility receive various events, including
919 * control requests the kernel doesn't handle. Drivers that don't
920 * use this facility may be too simple-minded for real applications.
923 static inline void ep0_readable (struct dev_data
*dev
)
925 wake_up (&dev
->wait
);
926 kill_fasync (&dev
->fasync
, SIGIO
, POLL_IN
);
929 static void clean_req (struct usb_ep
*ep
, struct usb_request
*req
)
931 struct dev_data
*dev
= ep
->driver_data
;
933 if (req
->buf
!= dev
->rbuf
) {
935 req
->buf
= dev
->rbuf
;
937 req
->complete
= epio_complete
;
938 dev
->setup_out_ready
= 0;
941 static void ep0_complete (struct usb_ep
*ep
, struct usb_request
*req
)
943 struct dev_data
*dev
= ep
->driver_data
;
947 /* for control OUT, data must still get to userspace */
948 spin_lock_irqsave(&dev
->lock
, flags
);
949 if (!dev
->setup_in
) {
950 dev
->setup_out_error
= (req
->status
!= 0);
951 if (!dev
->setup_out_error
)
953 dev
->setup_out_ready
= 1;
957 /* clean up as appropriate */
958 if (free
&& req
->buf
!= &dev
->rbuf
)
960 req
->complete
= epio_complete
;
961 spin_unlock_irqrestore(&dev
->lock
, flags
);
964 static int setup_req (struct usb_ep
*ep
, struct usb_request
*req
, u16 len
)
966 struct dev_data
*dev
= ep
->driver_data
;
968 if (dev
->setup_out_ready
) {
969 DBG (dev
, "ep0 request busy!\n");
972 if (len
> sizeof (dev
->rbuf
))
973 req
->buf
= kmalloc(len
, GFP_ATOMIC
);
974 if (req
->buf
== NULL
) {
975 req
->buf
= dev
->rbuf
;
978 req
->complete
= ep0_complete
;
985 ep0_read (struct file
*fd
, char __user
*buf
, size_t len
, loff_t
*ptr
)
987 struct dev_data
*dev
= fd
->private_data
;
989 enum ep0_state state
;
991 spin_lock_irq (&dev
->lock
);
993 /* report fd mode change before acting on it */
994 if (dev
->setup_abort
) {
995 dev
->setup_abort
= 0;
1000 /* control DATA stage */
1001 if ((state
= dev
->state
) == STATE_DEV_SETUP
) {
1003 if (dev
->setup_in
) { /* stall IN */
1004 VDEBUG(dev
, "ep0in stall\n");
1005 (void) usb_ep_set_halt (dev
->gadget
->ep0
);
1007 dev
->state
= STATE_DEV_CONNECTED
;
1009 } else if (len
== 0) { /* ack SET_CONFIGURATION etc */
1010 struct usb_ep
*ep
= dev
->gadget
->ep0
;
1011 struct usb_request
*req
= dev
->req
;
1013 if ((retval
= setup_req (ep
, req
, 0)) == 0)
1014 retval
= usb_ep_queue (ep
, req
, GFP_ATOMIC
);
1015 dev
->state
= STATE_DEV_CONNECTED
;
1017 /* assume that was SET_CONFIGURATION */
1018 if (dev
->current_config
) {
1021 if (gadget_is_dualspeed(dev
->gadget
)
1022 && (dev
->gadget
->speed
1024 power
= dev
->hs_config
->bMaxPower
;
1026 power
= dev
->config
->bMaxPower
;
1027 usb_gadget_vbus_draw(dev
->gadget
, 2 * power
);
1030 } else { /* collect OUT data */
1031 if ((fd
->f_flags
& O_NONBLOCK
) != 0
1032 && !dev
->setup_out_ready
) {
1036 spin_unlock_irq (&dev
->lock
);
1037 retval
= wait_event_interruptible (dev
->wait
,
1038 dev
->setup_out_ready
!= 0);
1040 /* FIXME state could change from under us */
1041 spin_lock_irq (&dev
->lock
);
1045 if (dev
->state
!= STATE_DEV_SETUP
) {
1046 retval
= -ECANCELED
;
1049 dev
->state
= STATE_DEV_CONNECTED
;
1051 if (dev
->setup_out_error
)
1054 len
= min (len
, (size_t)dev
->req
->actual
);
1055 // FIXME don't call this with the spinlock held ...
1056 if (copy_to_user (buf
, dev
->req
->buf
, len
))
1060 clean_req (dev
->gadget
->ep0
, dev
->req
);
1061 /* NOTE userspace can't yet choose to stall */
1067 /* else normal: return event data */
1068 if (len
< sizeof dev
->event
[0]) {
1072 len
-= len
% sizeof (struct usb_gadgetfs_event
);
1073 dev
->usermode_setup
= 1;
1076 /* return queued events right away */
1077 if (dev
->ev_next
!= 0) {
1080 n
= len
/ sizeof (struct usb_gadgetfs_event
);
1081 if (dev
->ev_next
< n
)
1084 /* ep0 i/o has special semantics during STATE_DEV_SETUP */
1085 for (i
= 0; i
< n
; i
++) {
1086 if (dev
->event
[i
].type
== GADGETFS_SETUP
) {
1087 dev
->state
= STATE_DEV_SETUP
;
1092 spin_unlock_irq (&dev
->lock
);
1093 len
= n
* sizeof (struct usb_gadgetfs_event
);
1094 if (copy_to_user (buf
, &dev
->event
, len
))
1099 /* NOTE this doesn't guard against broken drivers;
1100 * concurrent ep0 readers may lose events.
1102 spin_lock_irq (&dev
->lock
);
1103 if (dev
->ev_next
> n
) {
1104 memmove(&dev
->event
[0], &dev
->event
[n
],
1105 sizeof (struct usb_gadgetfs_event
)
1106 * (dev
->ev_next
- n
));
1109 spin_unlock_irq (&dev
->lock
);
1113 if (fd
->f_flags
& O_NONBLOCK
) {
1120 DBG (dev
, "fail %s, state %d\n", __func__
, state
);
1123 case STATE_DEV_UNCONNECTED
:
1124 case STATE_DEV_CONNECTED
:
1125 spin_unlock_irq (&dev
->lock
);
1126 DBG (dev
, "%s wait\n", __func__
);
1128 /* wait for events */
1129 retval
= wait_event_interruptible (dev
->wait
,
1133 spin_lock_irq (&dev
->lock
);
1138 spin_unlock_irq (&dev
->lock
);
1142 static struct usb_gadgetfs_event
*
1143 next_event (struct dev_data
*dev
, enum usb_gadgetfs_event_type type
)
1145 struct usb_gadgetfs_event
*event
;
1149 /* these events purge the queue */
1150 case GADGETFS_DISCONNECT
:
1151 if (dev
->state
== STATE_DEV_SETUP
)
1152 dev
->setup_abort
= 1;
1154 case GADGETFS_CONNECT
:
1157 case GADGETFS_SETUP
: /* previous request timed out */
1158 case GADGETFS_SUSPEND
: /* same effect */
1159 /* these events can't be repeated */
1160 for (i
= 0; i
!= dev
->ev_next
; i
++) {
1161 if (dev
->event
[i
].type
!= type
)
1163 DBG(dev
, "discard old event[%d] %d\n", i
, type
);
1165 if (i
== dev
->ev_next
)
1167 /* indices start at zero, for simplicity */
1168 memmove (&dev
->event
[i
], &dev
->event
[i
+ 1],
1169 sizeof (struct usb_gadgetfs_event
)
1170 * (dev
->ev_next
- i
));
1176 VDEBUG(dev
, "event[%d] = %d\n", dev
->ev_next
, type
);
1177 event
= &dev
->event
[dev
->ev_next
++];
1178 BUG_ON (dev
->ev_next
> N_EVENT
);
1179 memset (event
, 0, sizeof *event
);
1185 ep0_write (struct file
*fd
, const char __user
*buf
, size_t len
, loff_t
*ptr
)
1187 struct dev_data
*dev
= fd
->private_data
;
1188 ssize_t retval
= -ESRCH
;
1190 spin_lock_irq (&dev
->lock
);
1192 /* report fd mode change before acting on it */
1193 if (dev
->setup_abort
) {
1194 dev
->setup_abort
= 0;
1197 /* data and/or status stage for control request */
1198 } else if (dev
->state
== STATE_DEV_SETUP
) {
1200 /* IN DATA+STATUS caller makes len <= wLength */
1201 if (dev
->setup_in
) {
1202 retval
= setup_req (dev
->gadget
->ep0
, dev
->req
, len
);
1204 dev
->state
= STATE_DEV_CONNECTED
;
1205 spin_unlock_irq (&dev
->lock
);
1206 if (copy_from_user (dev
->req
->buf
, buf
, len
))
1209 if (len
< dev
->setup_wLength
)
1211 retval
= usb_ep_queue (
1212 dev
->gadget
->ep0
, dev
->req
,
1216 spin_lock_irq (&dev
->lock
);
1217 clean_req (dev
->gadget
->ep0
, dev
->req
);
1218 spin_unlock_irq (&dev
->lock
);
1225 /* can stall some OUT transfers */
1226 } else if (dev
->setup_can_stall
) {
1227 VDEBUG(dev
, "ep0out stall\n");
1228 (void) usb_ep_set_halt (dev
->gadget
->ep0
);
1230 dev
->state
= STATE_DEV_CONNECTED
;
1232 DBG(dev
, "bogus ep0out stall!\n");
1235 DBG (dev
, "fail %s, state %d\n", __func__
, dev
->state
);
1237 spin_unlock_irq (&dev
->lock
);
1242 ep0_fasync (int f
, struct file
*fd
, int on
)
1244 struct dev_data
*dev
= fd
->private_data
;
1245 // caller must F_SETOWN before signal delivery happens
1246 VDEBUG (dev
, "%s %s\n", __func__
, on
? "on" : "off");
1247 return fasync_helper (f
, fd
, on
, &dev
->fasync
);
1250 static struct usb_gadget_driver gadgetfs_driver
;
1253 dev_release (struct inode
*inode
, struct file
*fd
)
1255 struct dev_data
*dev
= fd
->private_data
;
1257 /* closing ep0 === shutdown all */
1259 usb_gadget_unregister_driver (&gadgetfs_driver
);
1261 /* at this point "good" hardware has disconnected the
1262 * device from USB; the host won't see it any more.
1263 * alternatively, all host requests will time out.
1269 /* other endpoints were all decoupled from this device */
1270 spin_lock_irq(&dev
->lock
);
1271 dev
->state
= STATE_DEV_DISABLED
;
1272 spin_unlock_irq(&dev
->lock
);
1279 ep0_poll (struct file
*fd
, poll_table
*wait
)
1281 struct dev_data
*dev
= fd
->private_data
;
1284 poll_wait(fd
, &dev
->wait
, wait
);
1286 spin_lock_irq (&dev
->lock
);
1288 /* report fd mode change before acting on it */
1289 if (dev
->setup_abort
) {
1290 dev
->setup_abort
= 0;
1295 if (dev
->state
== STATE_DEV_SETUP
) {
1296 if (dev
->setup_in
|| dev
->setup_can_stall
)
1299 if (dev
->ev_next
!= 0)
1303 spin_unlock_irq(&dev
->lock
);
1307 static long dev_ioctl (struct file
*fd
, unsigned code
, unsigned long value
)
1309 struct dev_data
*dev
= fd
->private_data
;
1310 struct usb_gadget
*gadget
= dev
->gadget
;
1313 if (gadget
->ops
->ioctl
)
1314 ret
= gadget
->ops
->ioctl (gadget
, code
, value
);
1319 /* used after device configuration */
1320 static const struct file_operations ep0_io_operations
= {
1321 .owner
= THIS_MODULE
,
1322 .llseek
= no_llseek
,
1326 .fasync
= ep0_fasync
,
1328 .unlocked_ioctl
= dev_ioctl
,
1329 .release
= dev_release
,
1332 /*----------------------------------------------------------------------*/
1334 /* The in-kernel gadget driver handles most ep0 issues, in particular
1335 * enumerating the single configuration (as provided from user space).
1337 * Unrecognized ep0 requests may be handled in user space.
1340 static void make_qualifier (struct dev_data
*dev
)
1342 struct usb_qualifier_descriptor qual
;
1343 struct usb_device_descriptor
*desc
;
1345 qual
.bLength
= sizeof qual
;
1346 qual
.bDescriptorType
= USB_DT_DEVICE_QUALIFIER
;
1347 qual
.bcdUSB
= cpu_to_le16 (0x0200);
1350 qual
.bDeviceClass
= desc
->bDeviceClass
;
1351 qual
.bDeviceSubClass
= desc
->bDeviceSubClass
;
1352 qual
.bDeviceProtocol
= desc
->bDeviceProtocol
;
1354 /* assumes ep0 uses the same value for both speeds ... */
1355 qual
.bMaxPacketSize0
= dev
->gadget
->ep0
->maxpacket
;
1357 qual
.bNumConfigurations
= 1;
1360 memcpy (dev
->rbuf
, &qual
, sizeof qual
);
1364 config_buf (struct dev_data
*dev
, u8 type
, unsigned index
)
1369 /* only one configuration */
1373 if (gadget_is_dualspeed(dev
->gadget
)) {
1374 hs
= (dev
->gadget
->speed
== USB_SPEED_HIGH
);
1375 if (type
== USB_DT_OTHER_SPEED_CONFIG
)
1379 dev
->req
->buf
= dev
->hs_config
;
1380 len
= le16_to_cpu(dev
->hs_config
->wTotalLength
);
1382 dev
->req
->buf
= dev
->config
;
1383 len
= le16_to_cpu(dev
->config
->wTotalLength
);
1385 ((u8
*)dev
->req
->buf
) [1] = type
;
1390 gadgetfs_setup (struct usb_gadget
*gadget
, const struct usb_ctrlrequest
*ctrl
)
1392 struct dev_data
*dev
= get_gadget_data (gadget
);
1393 struct usb_request
*req
= dev
->req
;
1394 int value
= -EOPNOTSUPP
;
1395 struct usb_gadgetfs_event
*event
;
1396 u16 w_value
= le16_to_cpu(ctrl
->wValue
);
1397 u16 w_length
= le16_to_cpu(ctrl
->wLength
);
1399 spin_lock (&dev
->lock
);
1400 dev
->setup_abort
= 0;
1401 if (dev
->state
== STATE_DEV_UNCONNECTED
) {
1402 if (gadget_is_dualspeed(gadget
)
1403 && gadget
->speed
== USB_SPEED_HIGH
1404 && dev
->hs_config
== NULL
) {
1405 spin_unlock(&dev
->lock
);
1406 ERROR (dev
, "no high speed config??\n");
1410 dev
->state
= STATE_DEV_CONNECTED
;
1412 INFO (dev
, "connected\n");
1413 event
= next_event (dev
, GADGETFS_CONNECT
);
1414 event
->u
.speed
= gadget
->speed
;
1417 /* host may have given up waiting for response. we can miss control
1418 * requests handled lower down (device/endpoint status and features);
1419 * then ep0_{read,write} will report the wrong status. controller
1420 * driver will have aborted pending i/o.
1422 } else if (dev
->state
== STATE_DEV_SETUP
)
1423 dev
->setup_abort
= 1;
1425 req
->buf
= dev
->rbuf
;
1426 req
->context
= NULL
;
1427 value
= -EOPNOTSUPP
;
1428 switch (ctrl
->bRequest
) {
1430 case USB_REQ_GET_DESCRIPTOR
:
1431 if (ctrl
->bRequestType
!= USB_DIR_IN
)
1433 switch (w_value
>> 8) {
1436 value
= min (w_length
, (u16
) sizeof *dev
->dev
);
1437 dev
->dev
->bMaxPacketSize0
= dev
->gadget
->ep0
->maxpacket
;
1438 req
->buf
= dev
->dev
;
1440 case USB_DT_DEVICE_QUALIFIER
:
1441 if (!dev
->hs_config
)
1443 value
= min (w_length
, (u16
)
1444 sizeof (struct usb_qualifier_descriptor
));
1445 make_qualifier (dev
);
1447 case USB_DT_OTHER_SPEED_CONFIG
:
1450 value
= config_buf (dev
,
1454 value
= min (w_length
, (u16
) value
);
1459 default: // all others are errors
1464 /* currently one config, two speeds */
1465 case USB_REQ_SET_CONFIGURATION
:
1466 if (ctrl
->bRequestType
!= 0)
1468 if (0 == (u8
) w_value
) {
1470 dev
->current_config
= 0;
1471 usb_gadget_vbus_draw(gadget
, 8 /* mA */ );
1472 // user mode expected to disable endpoints
1476 if (gadget_is_dualspeed(gadget
)
1477 && gadget
->speed
== USB_SPEED_HIGH
) {
1478 config
= dev
->hs_config
->bConfigurationValue
;
1479 power
= dev
->hs_config
->bMaxPower
;
1481 config
= dev
->config
->bConfigurationValue
;
1482 power
= dev
->config
->bMaxPower
;
1485 if (config
== (u8
) w_value
) {
1487 dev
->current_config
= config
;
1488 usb_gadget_vbus_draw(gadget
, 2 * power
);
1492 /* report SET_CONFIGURATION like any other control request,
1493 * except that usermode may not stall this. the next
1494 * request mustn't be allowed start until this finishes:
1495 * endpoints and threads set up, etc.
1497 * NOTE: older PXA hardware (before PXA 255: without UDCCFR)
1498 * has bad/racey automagic that prevents synchronizing here.
1499 * even kernel mode drivers often miss them.
1502 INFO (dev
, "configuration #%d\n", dev
->current_config
);
1503 usb_gadget_set_state(gadget
, USB_STATE_CONFIGURED
);
1504 if (dev
->usermode_setup
) {
1505 dev
->setup_can_stall
= 0;
1511 #ifndef CONFIG_USB_PXA25X
1512 /* PXA automagically handles this request too */
1513 case USB_REQ_GET_CONFIGURATION
:
1514 if (ctrl
->bRequestType
!= 0x80)
1516 *(u8
*)req
->buf
= dev
->current_config
;
1517 value
= min (w_length
, (u16
) 1);
1523 VDEBUG (dev
, "%s req%02x.%02x v%04x i%04x l%d\n",
1524 dev
->usermode_setup
? "delegate" : "fail",
1525 ctrl
->bRequestType
, ctrl
->bRequest
,
1526 w_value
, le16_to_cpu(ctrl
->wIndex
), w_length
);
1528 /* if there's an ep0 reader, don't stall */
1529 if (dev
->usermode_setup
) {
1530 dev
->setup_can_stall
= 1;
1532 dev
->setup_in
= (ctrl
->bRequestType
& USB_DIR_IN
)
1534 dev
->setup_wLength
= w_length
;
1535 dev
->setup_out_ready
= 0;
1536 dev
->setup_out_error
= 0;
1539 /* read DATA stage for OUT right away */
1540 if (unlikely (!dev
->setup_in
&& w_length
)) {
1541 value
= setup_req (gadget
->ep0
, dev
->req
,
1545 value
= usb_ep_queue (gadget
->ep0
, dev
->req
,
1548 clean_req (gadget
->ep0
, dev
->req
);
1552 /* we can't currently stall these */
1553 dev
->setup_can_stall
= 0;
1556 /* state changes when reader collects event */
1557 event
= next_event (dev
, GADGETFS_SETUP
);
1558 event
->u
.setup
= *ctrl
;
1560 spin_unlock (&dev
->lock
);
1565 /* proceed with data transfer and status phases? */
1566 if (value
>= 0 && dev
->state
!= STATE_DEV_SETUP
) {
1567 req
->length
= value
;
1568 req
->zero
= value
< w_length
;
1569 value
= usb_ep_queue (gadget
->ep0
, req
, GFP_ATOMIC
);
1571 DBG (dev
, "ep_queue --> %d\n", value
);
1576 /* device stalls when value < 0 */
1577 spin_unlock (&dev
->lock
);
1581 static void destroy_ep_files (struct dev_data
*dev
)
1583 DBG (dev
, "%s %d\n", __func__
, dev
->state
);
1585 /* dev->state must prevent interference */
1586 spin_lock_irq (&dev
->lock
);
1587 while (!list_empty(&dev
->epfiles
)) {
1589 struct inode
*parent
;
1590 struct dentry
*dentry
;
1592 /* break link to FS */
1593 ep
= list_first_entry (&dev
->epfiles
, struct ep_data
, epfiles
);
1594 list_del_init (&ep
->epfiles
);
1595 dentry
= ep
->dentry
;
1597 parent
= dentry
->d_parent
->d_inode
;
1599 /* break link to controller */
1600 if (ep
->state
== STATE_EP_ENABLED
)
1601 (void) usb_ep_disable (ep
->ep
);
1602 ep
->state
= STATE_EP_UNBOUND
;
1603 usb_ep_free_request (ep
->ep
, ep
->req
);
1605 wake_up (&ep
->wait
);
1608 spin_unlock_irq (&dev
->lock
);
1610 /* break link to dcache */
1611 mutex_lock (&parent
->i_mutex
);
1614 mutex_unlock (&parent
->i_mutex
);
1616 spin_lock_irq (&dev
->lock
);
1618 spin_unlock_irq (&dev
->lock
);
1622 static struct dentry
*
1623 gadgetfs_create_file (struct super_block
*sb
, char const *name
,
1624 void *data
, const struct file_operations
*fops
);
1626 static int activate_ep_files (struct dev_data
*dev
)
1629 struct ep_data
*data
;
1631 gadget_for_each_ep (ep
, dev
->gadget
) {
1633 data
= kzalloc(sizeof(*data
), GFP_KERNEL
);
1636 data
->state
= STATE_EP_DISABLED
;
1637 mutex_init(&data
->lock
);
1638 init_waitqueue_head (&data
->wait
);
1640 strncpy (data
->name
, ep
->name
, sizeof (data
->name
) - 1);
1641 atomic_set (&data
->count
, 1);
1646 ep
->driver_data
= data
;
1648 data
->req
= usb_ep_alloc_request (ep
, GFP_KERNEL
);
1652 data
->dentry
= gadgetfs_create_file (dev
->sb
, data
->name
,
1653 data
, &ep_config_operations
);
1656 list_add_tail (&data
->epfiles
, &dev
->epfiles
);
1661 usb_ep_free_request (ep
, data
->req
);
1666 DBG (dev
, "%s enomem\n", __func__
);
1667 destroy_ep_files (dev
);
1672 gadgetfs_unbind (struct usb_gadget
*gadget
)
1674 struct dev_data
*dev
= get_gadget_data (gadget
);
1676 DBG (dev
, "%s\n", __func__
);
1678 spin_lock_irq (&dev
->lock
);
1679 dev
->state
= STATE_DEV_UNBOUND
;
1680 spin_unlock_irq (&dev
->lock
);
1682 destroy_ep_files (dev
);
1683 gadget
->ep0
->driver_data
= NULL
;
1684 set_gadget_data (gadget
, NULL
);
1686 /* we've already been disconnected ... no i/o is active */
1688 usb_ep_free_request (gadget
->ep0
, dev
->req
);
1689 DBG (dev
, "%s done\n", __func__
);
1693 static struct dev_data
*the_device
;
1695 static int gadgetfs_bind(struct usb_gadget
*gadget
,
1696 struct usb_gadget_driver
*driver
)
1698 struct dev_data
*dev
= the_device
;
1702 if (0 != strcmp (CHIP
, gadget
->name
)) {
1703 pr_err("%s expected %s controller not %s\n",
1704 shortname
, CHIP
, gadget
->name
);
1708 set_gadget_data (gadget
, dev
);
1709 dev
->gadget
= gadget
;
1710 gadget
->ep0
->driver_data
= dev
;
1712 /* preallocate control response and buffer */
1713 dev
->req
= usb_ep_alloc_request (gadget
->ep0
, GFP_KERNEL
);
1716 dev
->req
->context
= NULL
;
1717 dev
->req
->complete
= epio_complete
;
1719 if (activate_ep_files (dev
) < 0)
1722 INFO (dev
, "bound to %s driver\n", gadget
->name
);
1723 spin_lock_irq(&dev
->lock
);
1724 dev
->state
= STATE_DEV_UNCONNECTED
;
1725 spin_unlock_irq(&dev
->lock
);
1730 gadgetfs_unbind (gadget
);
1735 gadgetfs_disconnect (struct usb_gadget
*gadget
)
1737 struct dev_data
*dev
= get_gadget_data (gadget
);
1738 unsigned long flags
;
1740 spin_lock_irqsave (&dev
->lock
, flags
);
1741 if (dev
->state
== STATE_DEV_UNCONNECTED
)
1743 dev
->state
= STATE_DEV_UNCONNECTED
;
1745 INFO (dev
, "disconnected\n");
1746 next_event (dev
, GADGETFS_DISCONNECT
);
1749 spin_unlock_irqrestore (&dev
->lock
, flags
);
1753 gadgetfs_suspend (struct usb_gadget
*gadget
)
1755 struct dev_data
*dev
= get_gadget_data (gadget
);
1757 INFO (dev
, "suspended from state %d\n", dev
->state
);
1758 spin_lock (&dev
->lock
);
1759 switch (dev
->state
) {
1760 case STATE_DEV_SETUP
: // VERY odd... host died??
1761 case STATE_DEV_CONNECTED
:
1762 case STATE_DEV_UNCONNECTED
:
1763 next_event (dev
, GADGETFS_SUSPEND
);
1769 spin_unlock (&dev
->lock
);
1772 static struct usb_gadget_driver gadgetfs_driver
= {
1773 .function
= (char *) driver_desc
,
1774 .bind
= gadgetfs_bind
,
1775 .unbind
= gadgetfs_unbind
,
1776 .setup
= gadgetfs_setup
,
1777 .reset
= gadgetfs_disconnect
,
1778 .disconnect
= gadgetfs_disconnect
,
1779 .suspend
= gadgetfs_suspend
,
1782 .name
= (char *) shortname
,
1786 /*----------------------------------------------------------------------*/
1788 static void gadgetfs_nop(struct usb_gadget
*arg
) { }
1790 static int gadgetfs_probe(struct usb_gadget
*gadget
,
1791 struct usb_gadget_driver
*driver
)
1793 CHIP
= gadget
->name
;
1797 static struct usb_gadget_driver probe_driver
= {
1798 .max_speed
= USB_SPEED_HIGH
,
1799 .bind
= gadgetfs_probe
,
1800 .unbind
= gadgetfs_nop
,
1801 .setup
= (void *)gadgetfs_nop
,
1802 .disconnect
= gadgetfs_nop
,
1809 /* DEVICE INITIALIZATION
1811 * fd = open ("/dev/gadget/$CHIP", O_RDWR)
1812 * status = write (fd, descriptors, sizeof descriptors)
1814 * That write establishes the device configuration, so the kernel can
1815 * bind to the controller ... guaranteeing it can handle enumeration
1816 * at all necessary speeds. Descriptor order is:
1818 * . message tag (u32, host order) ... for now, must be zero; it
1819 * would change to support features like multi-config devices
1820 * . full/low speed config ... all wTotalLength bytes (with interface,
1821 * class, altsetting, endpoint, and other descriptors)
1822 * . high speed config ... all descriptors, for high speed operation;
1823 * this one's optional except for high-speed hardware
1824 * . device descriptor
1826 * Endpoints are not yet enabled. Drivers must wait until device
1827 * configuration and interface altsetting changes create
1828 * the need to configure (or unconfigure) them.
1830 * After initialization, the device stays active for as long as that
1831 * $CHIP file is open. Events must then be read from that descriptor,
1832 * such as configuration notifications.
1835 static int is_valid_config (struct usb_config_descriptor
*config
)
1837 return config
->bDescriptorType
== USB_DT_CONFIG
1838 && config
->bLength
== USB_DT_CONFIG_SIZE
1839 && config
->bConfigurationValue
!= 0
1840 && (config
->bmAttributes
& USB_CONFIG_ATT_ONE
) != 0
1841 && (config
->bmAttributes
& USB_CONFIG_ATT_WAKEUP
) == 0;
1842 /* FIXME if gadget->is_otg, _must_ include an otg descriptor */
1843 /* FIXME check lengths: walk to end */
1847 dev_config (struct file
*fd
, const char __user
*buf
, size_t len
, loff_t
*ptr
)
1849 struct dev_data
*dev
= fd
->private_data
;
1850 ssize_t value
= len
, length
= len
;
1855 if (len
< (USB_DT_CONFIG_SIZE
+ USB_DT_DEVICE_SIZE
+ 4))
1858 /* we might need to change message format someday */
1859 if (copy_from_user (&tag
, buf
, 4))
1866 kbuf
= memdup_user(buf
, length
);
1868 return PTR_ERR(kbuf
);
1870 spin_lock_irq (&dev
->lock
);
1876 /* full or low speed config */
1877 dev
->config
= (void *) kbuf
;
1878 total
= le16_to_cpu(dev
->config
->wTotalLength
);
1879 if (!is_valid_config (dev
->config
) || total
>= length
)
1884 /* optional high speed config */
1885 if (kbuf
[1] == USB_DT_CONFIG
) {
1886 dev
->hs_config
= (void *) kbuf
;
1887 total
= le16_to_cpu(dev
->hs_config
->wTotalLength
);
1888 if (!is_valid_config (dev
->hs_config
) || total
>= length
)
1894 /* could support multiple configs, using another encoding! */
1896 /* device descriptor (tweaked for paranoia) */
1897 if (length
!= USB_DT_DEVICE_SIZE
)
1899 dev
->dev
= (void *)kbuf
;
1900 if (dev
->dev
->bLength
!= USB_DT_DEVICE_SIZE
1901 || dev
->dev
->bDescriptorType
!= USB_DT_DEVICE
1902 || dev
->dev
->bNumConfigurations
!= 1)
1904 dev
->dev
->bNumConfigurations
= 1;
1905 dev
->dev
->bcdUSB
= cpu_to_le16 (0x0200);
1907 /* triggers gadgetfs_bind(); then we can enumerate. */
1908 spin_unlock_irq (&dev
->lock
);
1910 gadgetfs_driver
.max_speed
= USB_SPEED_HIGH
;
1912 gadgetfs_driver
.max_speed
= USB_SPEED_FULL
;
1914 value
= usb_gadget_probe_driver(&gadgetfs_driver
);
1919 /* at this point "good" hardware has for the first time
1920 * let the USB the host see us. alternatively, if users
1921 * unplug/replug that will clear all the error state.
1923 * note: everything running before here was guaranteed
1924 * to choke driver model style diagnostics. from here
1925 * on, they can work ... except in cleanup paths that
1926 * kick in after the ep0 descriptor is closed.
1928 fd
->f_op
= &ep0_io_operations
;
1934 spin_unlock_irq (&dev
->lock
);
1935 pr_debug ("%s: %s fail %Zd, %p\n", shortname
, __func__
, value
, dev
);
1942 dev_open (struct inode
*inode
, struct file
*fd
)
1944 struct dev_data
*dev
= inode
->i_private
;
1947 spin_lock_irq(&dev
->lock
);
1948 if (dev
->state
== STATE_DEV_DISABLED
) {
1950 dev
->state
= STATE_DEV_OPENED
;
1951 fd
->private_data
= dev
;
1955 spin_unlock_irq(&dev
->lock
);
1959 static const struct file_operations dev_init_operations
= {
1960 .llseek
= no_llseek
,
1963 .write
= dev_config
,
1964 .fasync
= ep0_fasync
,
1965 .unlocked_ioctl
= dev_ioctl
,
1966 .release
= dev_release
,
1969 /*----------------------------------------------------------------------*/
1971 /* FILESYSTEM AND SUPERBLOCK OPERATIONS
1973 * Mounting the filesystem creates a controller file, used first for
1974 * device configuration then later for event monitoring.
1978 /* FIXME PAM etc could set this security policy without mount options
1979 * if epfiles inherited ownership and permissons from ep0 ...
1982 static unsigned default_uid
;
1983 static unsigned default_gid
;
1984 static unsigned default_perm
= S_IRUSR
| S_IWUSR
;
1986 module_param (default_uid
, uint
, 0644);
1987 module_param (default_gid
, uint
, 0644);
1988 module_param (default_perm
, uint
, 0644);
1991 static struct inode
*
1992 gadgetfs_make_inode (struct super_block
*sb
,
1993 void *data
, const struct file_operations
*fops
,
1996 struct inode
*inode
= new_inode (sb
);
1999 inode
->i_ino
= get_next_ino();
2000 inode
->i_mode
= mode
;
2001 inode
->i_uid
= make_kuid(&init_user_ns
, default_uid
);
2002 inode
->i_gid
= make_kgid(&init_user_ns
, default_gid
);
2003 inode
->i_atime
= inode
->i_mtime
= inode
->i_ctime
2005 inode
->i_private
= data
;
2006 inode
->i_fop
= fops
;
2011 /* creates in fs root directory, so non-renamable and non-linkable.
2012 * so inode and dentry are paired, until device reconfig.
2014 static struct dentry
*
2015 gadgetfs_create_file (struct super_block
*sb
, char const *name
,
2016 void *data
, const struct file_operations
*fops
)
2018 struct dentry
*dentry
;
2019 struct inode
*inode
;
2021 dentry
= d_alloc_name(sb
->s_root
, name
);
2025 inode
= gadgetfs_make_inode (sb
, data
, fops
,
2026 S_IFREG
| (default_perm
& S_IRWXUGO
));
2031 d_add (dentry
, inode
);
2035 static const struct super_operations gadget_fs_operations
= {
2036 .statfs
= simple_statfs
,
2037 .drop_inode
= generic_delete_inode
,
2041 gadgetfs_fill_super (struct super_block
*sb
, void *opts
, int silent
)
2043 struct inode
*inode
;
2044 struct dev_data
*dev
;
2049 /* fake probe to determine $CHIP */
2051 usb_gadget_probe_driver(&probe_driver
);
2056 sb
->s_blocksize
= PAGE_CACHE_SIZE
;
2057 sb
->s_blocksize_bits
= PAGE_CACHE_SHIFT
;
2058 sb
->s_magic
= GADGETFS_MAGIC
;
2059 sb
->s_op
= &gadget_fs_operations
;
2060 sb
->s_time_gran
= 1;
2063 inode
= gadgetfs_make_inode (sb
,
2064 NULL
, &simple_dir_operations
,
2065 S_IFDIR
| S_IRUGO
| S_IXUGO
);
2068 inode
->i_op
= &simple_dir_inode_operations
;
2069 if (!(sb
->s_root
= d_make_root (inode
)))
2072 /* the ep0 file is named after the controller we expect;
2073 * user mode code can use it for sanity checks, like we do.
2080 dev
->dentry
= gadgetfs_create_file(sb
, CHIP
, dev
, &dev_init_operations
);
2086 /* other endpoint files are available after hardware setup,
2087 * from binding to a controller.
2096 /* "mount -t gadgetfs path /dev/gadget" ends up here */
2097 static struct dentry
*
2098 gadgetfs_mount (struct file_system_type
*t
, int flags
,
2099 const char *path
, void *opts
)
2101 return mount_single (t
, flags
, opts
, gadgetfs_fill_super
);
2105 gadgetfs_kill_sb (struct super_block
*sb
)
2107 kill_litter_super (sb
);
2109 put_dev (the_device
);
2114 /*----------------------------------------------------------------------*/
2116 static struct file_system_type gadgetfs_type
= {
2117 .owner
= THIS_MODULE
,
2119 .mount
= gadgetfs_mount
,
2120 .kill_sb
= gadgetfs_kill_sb
,
2122 MODULE_ALIAS_FS("gadgetfs");
2124 /*----------------------------------------------------------------------*/
2126 static int __init
init (void)
2130 status
= register_filesystem (&gadgetfs_type
);
2132 pr_info ("%s: %s, version " DRIVER_VERSION
"\n",
2133 shortname
, driver_desc
);
2138 static void __exit
cleanup (void)
2140 pr_debug ("unregister %s\n", shortname
);
2141 unregister_filesystem (&gadgetfs_type
);
2143 module_exit (cleanup
);