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Committer: Michael Beasley <mike@snafu.setup>
[mikesnafu-overlay.git] / drivers / usb / gadget / inode.c
blob0a6feafc8d2847ef39ab4ed3c74cac750e8b931c
1 /*
2 * inode.c -- user mode filesystem api for usb gadget controllers
3 *
4 * Copyright (C) 2003-2004 David Brownell
5 * Copyright (C) 2003 Agilent Technologies
6 *
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.
11 *
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
16 *
17 * You should have received a copy of the GNU General Public License
18 * along with this program; if not, write to the Free Software
19 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
20 */
21
22
23 /* #define VERBOSE_DEBUG */
24
25 #include <linux/init.h>
26 #include <linux/module.h>
27 #include <linux/fs.h>
28 #include <linux/pagemap.h>
29 #include <linux/uts.h>
30 #include <linux/wait.h>
31 #include <linux/compiler.h>
32 #include <asm/uaccess.h>
33 #include <linux/slab.h>
34 #include <linux/poll.h>
35
36 #include <linux/device.h>
37 #include <linux/moduleparam.h>
38
39 #include <linux/usb/gadgetfs.h>
40 #include <linux/usb/gadget.h>
41
42
43 /*
44 * The gadgetfs API maps each endpoint to a file descriptor so that you
45 * can use standard synchronous read/write calls for I/O. There's some
46 * O_NONBLOCK and O_ASYNC/FASYNC style i/o support. Example usermode
47 * drivers show how this works in practice. You can also use AIO to
48 * eliminate I/O gaps between requests, to help when streaming data.
49 *
50 * Key parts that must be USB-specific are protocols defining how the
51 * read/write operations relate to the hardware state machines. There
52 * are two types of files. One type is for the device, implementing ep0.
53 * The other type is for each IN or OUT endpoint. In both cases, the
54 * user mode driver must configure the hardware before using it.
55 *
56 * - First, dev_config() is called when /dev/gadget/$CHIP is configured
57 * (by writing configuration and device descriptors). Afterwards it
58 * may serve as a source of device events, used to handle all control
59 * requests other than basic enumeration.
60 *
61 * - Then, after a SET_CONFIGURATION control request, ep_config() is
62 * called when each /dev/gadget/ep* file is configured (by writing
63 * endpoint descriptors). Afterwards these files are used to write()
64 * IN data or to read() OUT data. To halt the endpoint, a "wrong
65 * direction" request is issued (like reading an IN endpoint).
66 *
67 * Unlike "usbfs" the only ioctl()s are for things that are rare, and maybe
68 * not possible on all hardware. For example, precise fault handling with
69 * respect to data left in endpoint fifos after aborted operations; or
70 * selective clearing of endpoint halts, to implement SET_INTERFACE.
71 */
72
73 #define DRIVER_DESC "USB Gadget filesystem"
74 #define DRIVER_VERSION "24 Aug 2004"
75
76 static const char driver_desc [] = DRIVER_DESC;
77 static const char shortname [] = "gadgetfs";
78
79 MODULE_DESCRIPTION (DRIVER_DESC);
80 MODULE_AUTHOR ("David Brownell");
81 MODULE_LICENSE ("GPL");
82
83
84 /*----------------------------------------------------------------------*/
85
86 #define GADGETFS_MAGIC 0xaee71ee7
87 #define DMA_ADDR_INVALID (~(dma_addr_t)0)
88
89 /* /dev/gadget/$CHIP represents ep0 and the whole device */
90 enum ep0_state {
91 /* DISBLED is the initial state.
92 */
93 STATE_DEV_DISABLED = 0,
94
95 /* Only one open() of /dev/gadget/$CHIP; only one file tracks
96 * ep0/device i/o modes and binding to the controller. Driver
97 * must always write descriptors to initialize the device, then
98 * the device becomes UNCONNECTED until enumeration.
99 */
100 STATE_DEV_OPENED,
101
102 /* From then on, ep0 fd is in either of two basic modes:
103 * - (UN)CONNECTED: read usb_gadgetfs_event(s) from it
104 * - SETUP: read/write will transfer control data and succeed;
105 * or if "wrong direction", performs protocol stall
106 */
107 STATE_DEV_UNCONNECTED,
108 STATE_DEV_CONNECTED,
109 STATE_DEV_SETUP,
110
111 /* UNBOUND means the driver closed ep0, so the device won't be
112 * accessible again (DEV_DISABLED) until all fds are closed.
113 */
114 STATE_DEV_UNBOUND,
115 };
116
117 /* enough for the whole queue: most events invalidate others */
118 #define N_EVENT 5
119
120 struct dev_data {
121 spinlock_t lock;
122 atomic_t count;
123 enum ep0_state state; /* P: lock */
124 struct usb_gadgetfs_event event [N_EVENT];
125 unsigned ev_next;
126 struct fasync_struct *fasync;
127 u8 current_config;
128
129 /* drivers reading ep0 MUST handle control requests (SETUP)
130 * reported that way; else the host will time out.
131 */
132 unsigned usermode_setup : 1,
133 setup_in : 1,
134 setup_can_stall : 1,
135 setup_out_ready : 1,
136 setup_out_error : 1,
137 setup_abort : 1;
138 unsigned setup_wLength;
139
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;
146 void *buf;
147 wait_queue_head_t wait;
148 struct super_block *sb;
149 struct dentry *dentry;
150
151 /* except this scratch i/o buffer for ep0 */
152 u8 rbuf [256];
153 };
154
155 static inline void get_dev (struct dev_data *data)
156 {
157 atomic_inc (&data->count);
158 }
159
160 static void put_dev (struct dev_data *data)
161 {
162 if (likely (!atomic_dec_and_test (&data->count)))
163 return;
164 /* needs no more cleanup */
165 BUG_ON (waitqueue_active (&data->wait));
166 kfree (data);
167 }
168
169 static struct dev_data *dev_new (void)
170 {
171 struct dev_data *dev;
172
173 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
174 if (!dev)
175 return NULL;
176 dev->state = STATE_DEV_DISABLED;
177 atomic_set (&dev->count, 1);
178 spin_lock_init (&dev->lock);
179 INIT_LIST_HEAD (&dev->epfiles);
180 init_waitqueue_head (&dev->wait);
181 return dev;
182 }
183
184 /*----------------------------------------------------------------------*/
185
186 /* other /dev/gadget/$ENDPOINT files represent endpoints */
187 enum ep_state {
188 STATE_EP_DISABLED = 0,
189 STATE_EP_READY,
190 STATE_EP_ENABLED,
191 STATE_EP_UNBOUND,
192 };
193
194 struct ep_data {
195 struct semaphore lock;
196 enum ep_state state;
197 atomic_t count;
198 struct dev_data *dev;
199 /* must hold dev->lock before accessing ep or req */
200 struct usb_ep *ep;
201 struct usb_request *req;
202 ssize_t status;
203 char name [16];
204 struct usb_endpoint_descriptor desc, hs_desc;
205 struct list_head epfiles;
206 wait_queue_head_t wait;
207 struct dentry *dentry;
208 struct inode *inode;
209 };
210
211 static inline void get_ep (struct ep_data *data)
212 {
213 atomic_inc (&data->count);
214 }
215
216 static void put_ep (struct ep_data *data)
217 {
218 if (likely (!atomic_dec_and_test (&data->count)))
219 return;
220 put_dev (data->dev);
221 /* needs no more cleanup */
222 BUG_ON (!list_empty (&data->epfiles));
223 BUG_ON (waitqueue_active (&data->wait));
224 kfree (data);
225 }
226
227 /*----------------------------------------------------------------------*/
228
229 /* most "how to use the hardware" policy choices are in userspace:
230 * mapping endpoint roles (which the driver needs) to the capabilities
231 * which the usb controller has. most of those capabilities are exposed
232 * implicitly, starting with the driver name and then endpoint names.
233 */
234
235 static const char *CHIP;
236
237 /*----------------------------------------------------------------------*/
238
239 /* NOTE: don't use dev_printk calls before binding to the gadget
240 * at the end of ep0 configuration, or after unbind.
241 */
242
243 /* too wordy: dev_printk(level , &(d)->gadget->dev , fmt , ## args) */
244 #define xprintk(d,level,fmt,args...) \
245 printk(level "%s: " fmt , shortname , ## args)
246
247 #ifdef DEBUG
248 #define DBG(dev,fmt,args...) \
249 xprintk(dev , KERN_DEBUG , fmt , ## args)
250 #else
251 #define DBG(dev,fmt,args...) \
252 do { } while (0)
253 #endif /* DEBUG */
254
255 #ifdef VERBOSE_DEBUG
256 #define VDEBUG DBG
257 #else
258 #define VDEBUG(dev,fmt,args...) \
259 do { } while (0)
260 #endif /* DEBUG */
261
262 #define ERROR(dev,fmt,args...) \
263 xprintk(dev , KERN_ERR , fmt , ## args)
264 #define WARN(dev,fmt,args...) \
265 xprintk(dev , KERN_WARNING , fmt , ## args)
266 #define INFO(dev,fmt,args...) \
267 xprintk(dev , KERN_INFO , fmt , ## args)
268
269
270 /*----------------------------------------------------------------------*/
271
272 /* SYNCHRONOUS ENDPOINT OPERATIONS (bulk/intr/iso)
273 *
274 * After opening, configure non-control endpoints. Then use normal
275 * stream read() and write() requests; and maybe ioctl() to get more
276 * precise FIFO status when recovering from cancellation.
277 */
278
279 static void epio_complete (struct usb_ep *ep, struct usb_request *req)
280 {
281 struct ep_data *epdata = ep->driver_data;
282
283 if (!req->context)
284 return;
285 if (req->status)
286 epdata->status = req->status;
287 else
288 epdata->status = req->actual;
289 complete ((struct completion *)req->context);
290 }
291
292 /* tasklock endpoint, returning when it's connected.
293 * still need dev->lock to use epdata->ep.
294 */
295 static int
296 get_ready_ep (unsigned f_flags, struct ep_data *epdata)
297 {
298 int val;
299
300 if (f_flags & O_NONBLOCK) {
301 if (down_trylock (&epdata->lock) != 0)
302 goto nonblock;
303 if (epdata->state != STATE_EP_ENABLED) {
304 up (&epdata->lock);
305 nonblock:
306 val = -EAGAIN;
307 } else
308 val = 0;
309 return val;
310 }
311
312 if ((val = down_interruptible (&epdata->lock)) < 0)
313 return val;
314
315 switch (epdata->state) {
316 case STATE_EP_ENABLED:
317 break;
318 // case STATE_EP_DISABLED: /* "can't happen" */
319 // case STATE_EP_READY: /* "can't happen" */
320 default: /* error! */
321 pr_debug ("%s: ep %p not available, state %d\n",
322 shortname, epdata, epdata->state);
323 // FALLTHROUGH
324 case STATE_EP_UNBOUND: /* clean disconnect */
325 val = -ENODEV;
326 up (&epdata->lock);
327 }
328 return val;
329 }
330
331 static ssize_t
332 ep_io (struct ep_data *epdata, void *buf, unsigned len)
333 {
334 DECLARE_COMPLETION_ONSTACK (done);
335 int value;
336
337 spin_lock_irq (&epdata->dev->lock);
338 if (likely (epdata->ep != NULL)) {
339 struct usb_request *req = epdata->req;
340
341 req->context = &done;
342 req->complete = epio_complete;
343 req->buf = buf;
344 req->length = len;
345 value = usb_ep_queue (epdata->ep, req, GFP_ATOMIC);
346 } else
347 value = -ENODEV;
348 spin_unlock_irq (&epdata->dev->lock);
349
350 if (likely (value == 0)) {
351 value = wait_event_interruptible (done.wait, done.done);
352 if (value != 0) {
353 spin_lock_irq (&epdata->dev->lock);
354 if (likely (epdata->ep != NULL)) {
355 DBG (epdata->dev, "%s i/o interrupted\n",
356 epdata->name);
357 usb_ep_dequeue (epdata->ep, epdata->req);
358 spin_unlock_irq (&epdata->dev->lock);
359
360 wait_event (done.wait, done.done);
361 if (epdata->status == -ECONNRESET)
362 epdata->status = -EINTR;
363 } else {
364 spin_unlock_irq (&epdata->dev->lock);
365
366 DBG (epdata->dev, "endpoint gone\n");
367 epdata->status = -ENODEV;
368 }
369 }
370 return epdata->status;
371 }
372 return value;
373 }
374
375
376 /* handle a synchronous OUT bulk/intr/iso transfer */
377 static ssize_t
378 ep_read (struct file *fd, char __user *buf, size_t len, loff_t *ptr)
379 {
380 struct ep_data *data = fd->private_data;
381 void *kbuf;
382 ssize_t value;
383
384 if ((value = get_ready_ep (fd->f_flags, data)) < 0)
385 return value;
386
387 /* halt any endpoint by doing a "wrong direction" i/o call */
388 if (data->desc.bEndpointAddress & USB_DIR_IN) {
389 if ((data->desc.bmAttributes & USB_ENDPOINT_XFERTYPE_MASK)
390 == USB_ENDPOINT_XFER_ISOC)
391 return -EINVAL;
392 DBG (data->dev, "%s halt\n", data->name);
393 spin_lock_irq (&data->dev->lock);
394 if (likely (data->ep != NULL))
395 usb_ep_set_halt (data->ep);
396 spin_unlock_irq (&data->dev->lock);
397 up (&data->lock);
398 return -EBADMSG;
399 }
400
401 /* FIXME readahead for O_NONBLOCK and poll(); careful with ZLPs */
402
403 value = -ENOMEM;
404 kbuf = kmalloc (len, GFP_KERNEL);
405 if (unlikely (!kbuf))
406 goto free1;
407
408 value = ep_io (data, kbuf, len);
409 VDEBUG (data->dev, "%s read %zu OUT, status %d\n",
410 data->name, len, (int) value);
411 if (value >= 0 && copy_to_user (buf, kbuf, value))
412 value = -EFAULT;
413
414 free1:
415 up (&data->lock);
416 kfree (kbuf);
417 return value;
418 }
419
420 /* handle a synchronous IN bulk/intr/iso transfer */
421 static ssize_t
422 ep_write (struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
423 {
424 struct ep_data *data = fd->private_data;
425 void *kbuf;
426 ssize_t value;
427
428 if ((value = get_ready_ep (fd->f_flags, data)) < 0)
429 return value;
430
431 /* halt any endpoint by doing a "wrong direction" i/o call */
432 if (!(data->desc.bEndpointAddress & USB_DIR_IN)) {
433 if ((data->desc.bmAttributes & USB_ENDPOINT_XFERTYPE_MASK)
434 == USB_ENDPOINT_XFER_ISOC)
435 return -EINVAL;
436 DBG (data->dev, "%s halt\n", data->name);
437 spin_lock_irq (&data->dev->lock);
438 if (likely (data->ep != NULL))
439 usb_ep_set_halt (data->ep);
440 spin_unlock_irq (&data->dev->lock);
441 up (&data->lock);
442 return -EBADMSG;
443 }
444
445 /* FIXME writebehind for O_NONBLOCK and poll(), qlen = 1 */
446
447 value = -ENOMEM;
448 kbuf = kmalloc (len, GFP_KERNEL);
449 if (!kbuf)
450 goto free1;
451 if (copy_from_user (kbuf, buf, len)) {
452 value = -EFAULT;
453 goto free1;
454 }
455
456 value = ep_io (data, kbuf, len);
457 VDEBUG (data->dev, "%s write %zu IN, status %d\n",
458 data->name, len, (int) value);
459 free1:
460 up (&data->lock);
461 kfree (kbuf);
462 return value;
463 }
464
465 static int
466 ep_release (struct inode *inode, struct file *fd)
467 {
468 struct ep_data *data = fd->private_data;
469 int value;
470
471 if ((value = down_interruptible(&data->lock)) < 0)
472 return value;
473
474 /* clean up if this can be reopened */
475 if (data->state != STATE_EP_UNBOUND) {
476 data->state = STATE_EP_DISABLED;
477 data->desc.bDescriptorType = 0;
478 data->hs_desc.bDescriptorType = 0;
479 usb_ep_disable(data->ep);
480 }
481 up (&data->lock);
482 put_ep (data);
483 return 0;
484 }
485
486 static int ep_ioctl (struct inode *inode, struct file *fd,
487 unsigned code, unsigned long value)
488 {
489 struct ep_data *data = fd->private_data;
490 int status;
491
492 if ((status = get_ready_ep (fd->f_flags, data)) < 0)
493 return status;
494
495 spin_lock_irq (&data->dev->lock);
496 if (likely (data->ep != NULL)) {
497 switch (code) {
498 case GADGETFS_FIFO_STATUS:
499 status = usb_ep_fifo_status (data->ep);
500 break;
501 case GADGETFS_FIFO_FLUSH:
502 usb_ep_fifo_flush (data->ep);
503 break;
504 case GADGETFS_CLEAR_HALT:
505 status = usb_ep_clear_halt (data->ep);
506 break;
507 default:
508 status = -ENOTTY;
509 }
510 } else
511 status = -ENODEV;
512 spin_unlock_irq (&data->dev->lock);
513 up (&data->lock);
514 return status;
515 }
516
517 /*----------------------------------------------------------------------*/
518
519 /* ASYNCHRONOUS ENDPOINT I/O OPERATIONS (bulk/intr/iso) */
520
521 struct kiocb_priv {
522 struct usb_request *req;
523 struct ep_data *epdata;
524 void *buf;
525 const struct iovec *iv;
526 unsigned long nr_segs;
527 unsigned actual;
528 };
529
530 static int ep_aio_cancel(struct kiocb *iocb, struct io_event *e)
531 {
532 struct kiocb_priv *priv = iocb->private;
533 struct ep_data *epdata;
534 int value;
535
536 local_irq_disable();
537 epdata = priv->epdata;
538 // spin_lock(&epdata->dev->lock);
539 kiocbSetCancelled(iocb);
540 if (likely(epdata && epdata->ep && priv->req))
541 value = usb_ep_dequeue (epdata->ep, priv->req);
542 else
543 value = -EINVAL;
544 // spin_unlock(&epdata->dev->lock);
545 local_irq_enable();
546
547 aio_put_req(iocb);
548 return value;
549 }
550
551 static ssize_t ep_aio_read_retry(struct kiocb *iocb)
552 {
553 struct kiocb_priv *priv = iocb->private;
554 ssize_t len, total;
555 void *to_copy;
556 int i;
557
558 /* we "retry" to get the right mm context for this: */
559
560 /* copy stuff into user buffers */
561 total = priv->actual;
562 len = 0;
563 to_copy = priv->buf;
564 for (i=0; i < priv->nr_segs; i++) {
565 ssize_t this = min((ssize_t)(priv->iv[i].iov_len), total);
566
567 if (copy_to_user(priv->iv[i].iov_base, to_copy, this)) {
568 if (len == 0)
569 len = -EFAULT;
570 break;
571 }
572
573 total -= this;
574 len += this;
575 to_copy += this;
576 if (total == 0)
577 break;
578 }
579 kfree(priv->buf);
580 kfree(priv);
581 return len;
582 }
583
584 static void ep_aio_complete(struct usb_ep *ep, struct usb_request *req)
585 {
586 struct kiocb *iocb = req->context;
587 struct kiocb_priv *priv = iocb->private;
588 struct ep_data *epdata = priv->epdata;
589
590 /* lock against disconnect (and ideally, cancel) */
591 spin_lock(&epdata->dev->lock);
592 priv->req = NULL;
593 priv->epdata = NULL;
594
595 /* if this was a write or a read returning no data then we
596 * don't need to copy anything to userspace, so we can
597 * complete the aio request immediately.
598 */
599 if (priv->iv == NULL || unlikely(req->actual == 0)) {
600 kfree(req->buf);
601 kfree(priv);
602 iocb->private = NULL;
603 /* aio_complete() reports bytes-transferred _and_ faults */
604 aio_complete(iocb, req->actual ? req->actual : req->status,
605 req->status);
606 } else {
607 /* retry() won't report both; so we hide some faults */
608 if (unlikely(0 != req->status))
609 DBG(epdata->dev, "%s fault %d len %d\n",
610 ep->name, req->status, req->actual);
611
612 priv->buf = req->buf;
613 priv->actual = req->actual;
614 kick_iocb(iocb);
615 }
616 spin_unlock(&epdata->dev->lock);
617
618 usb_ep_free_request(ep, req);
619 put_ep(epdata);
620 }
621
622 static ssize_t
623 ep_aio_rwtail(
624 struct kiocb *iocb,
625 char *buf,
626 size_t len,
627 struct ep_data *epdata,
628 const struct iovec *iv,
629 unsigned long nr_segs
630 )
631 {
632 struct kiocb_priv *priv;
633 struct usb_request *req;
634 ssize_t value;
635
636 priv = kmalloc(sizeof *priv, GFP_KERNEL);
637 if (!priv) {
638 value = -ENOMEM;
639 fail:
640 kfree(buf);
641 return value;
642 }
643 iocb->private = priv;
644 priv->iv = iv;
645 priv->nr_segs = nr_segs;
646
647 value = get_ready_ep(iocb->ki_filp->f_flags, epdata);
648 if (unlikely(value < 0)) {
649 kfree(priv);
650 goto fail;
651 }
652
653 iocb->ki_cancel = ep_aio_cancel;
654 get_ep(epdata);
655 priv->epdata = epdata;
656 priv->actual = 0;
657
658 /* each kiocb is coupled to one usb_request, but we can't
659 * allocate or submit those if the host disconnected.
660 */
661 spin_lock_irq(&epdata->dev->lock);
662 if (likely(epdata->ep)) {
663 req = usb_ep_alloc_request(epdata->ep, GFP_ATOMIC);
664 if (likely(req)) {
665 priv->req = req;
666 req->buf = buf;
667 req->length = len;
668 req->complete = ep_aio_complete;
669 req->context = iocb;
670 value = usb_ep_queue(epdata->ep, req, GFP_ATOMIC);
671 if (unlikely(0 != value))
672 usb_ep_free_request(epdata->ep, req);
673 } else
674 value = -EAGAIN;
675 } else
676 value = -ENODEV;
677 spin_unlock_irq(&epdata->dev->lock);
678
679 up(&epdata->lock);
680
681 if (unlikely(value)) {
682 kfree(priv);
683 put_ep(epdata);
684 } else
685 value = (iv ? -EIOCBRETRY : -EIOCBQUEUED);
686 return value;
687 }
688
689 static ssize_t
690 ep_aio_read(struct kiocb *iocb, const struct iovec *iov,
691 unsigned long nr_segs, loff_t o)
692 {
693 struct ep_data *epdata = iocb->ki_filp->private_data;
694 char *buf;
695
696 if (unlikely(epdata->desc.bEndpointAddress & USB_DIR_IN))
697 return -EINVAL;
698
699 buf = kmalloc(iocb->ki_left, GFP_KERNEL);
700 if (unlikely(!buf))
701 return -ENOMEM;
702
703 iocb->ki_retry = ep_aio_read_retry;
704 return ep_aio_rwtail(iocb, buf, iocb->ki_left, epdata, iov, nr_segs);
705 }
706
707 static ssize_t
708 ep_aio_write(struct kiocb *iocb, const struct iovec *iov,
709 unsigned long nr_segs, loff_t o)
710 {
711 struct ep_data *epdata = iocb->ki_filp->private_data;
712 char *buf;
713 size_t len = 0;
714 int i = 0;
715
716 if (unlikely(!(epdata->desc.bEndpointAddress & USB_DIR_IN)))
717 return -EINVAL;
718
719 buf = kmalloc(iocb->ki_left, GFP_KERNEL);
720 if (unlikely(!buf))
721 return -ENOMEM;
722
723 for (i=0; i < nr_segs; i++) {
724 if (unlikely(copy_from_user(&buf[len], iov[i].iov_base,
725 iov[i].iov_len) != 0)) {
726 kfree(buf);
727 return -EFAULT;
728 }
729 len += iov[i].iov_len;
730 }
731 return ep_aio_rwtail(iocb, buf, len, epdata, NULL, 0);
732 }
733
734 /*----------------------------------------------------------------------*/
735
736 /* used after endpoint configuration */
737 static const struct file_operations ep_io_operations = {
738 .owner = THIS_MODULE,
739 .llseek = no_llseek,
740
741 .read = ep_read,
742 .write = ep_write,
743 .ioctl = ep_ioctl,
744 .release = ep_release,
745
746 .aio_read = ep_aio_read,
747 .aio_write = ep_aio_write,
748 };
749
750 /* ENDPOINT INITIALIZATION
751 *
752 * fd = open ("/dev/gadget/$ENDPOINT", O_RDWR)
753 * status = write (fd, descriptors, sizeof descriptors)
754 *
755 * That write establishes the endpoint configuration, configuring
756 * the controller to process bulk, interrupt, or isochronous transfers
757 * at the right maxpacket size, and so on.
758 *
759 * The descriptors are message type 1, identified by a host order u32
760 * at the beginning of what's written. Descriptor order is: full/low
761 * speed descriptor, then optional high speed descriptor.
762 */
763 static ssize_t
764 ep_config (struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
765 {
766 struct ep_data *data = fd->private_data;
767 struct usb_ep *ep;
768 u32 tag;
769 int value, length = len;
770
771 if ((value = down_interruptible (&data->lock)) < 0)
772 return value;
773
774 if (data->state != STATE_EP_READY) {
775 value = -EL2HLT;
776 goto fail;
777 }
778
779 value = len;
780 if (len < USB_DT_ENDPOINT_SIZE + 4)
781 goto fail0;
782
783 /* we might need to change message format someday */
784 if (copy_from_user (&tag, buf, 4)) {
785 goto fail1;
786 }
787 if (tag != 1) {
788 DBG(data->dev, "config %s, bad tag %d\n", data->name, tag);
789 goto fail0;
790 }
791 buf += 4;
792 len -= 4;
793
794 /* NOTE: audio endpoint extensions not accepted here;
795 * just don't include the extra bytes.
796 */
797
798 /* full/low speed descriptor, then high speed */
799 if (copy_from_user (&data->desc, buf, USB_DT_ENDPOINT_SIZE)) {
800 goto fail1;
801 }
802 if (data->desc.bLength != USB_DT_ENDPOINT_SIZE
803 || data->desc.bDescriptorType != USB_DT_ENDPOINT)
804 goto fail0;
805 if (len != USB_DT_ENDPOINT_SIZE) {
806 if (len != 2 * USB_DT_ENDPOINT_SIZE)
807 goto fail0;
808 if (copy_from_user (&data->hs_desc, buf + USB_DT_ENDPOINT_SIZE,
809 USB_DT_ENDPOINT_SIZE)) {
810 goto fail1;
811 }
812 if (data->hs_desc.bLength != USB_DT_ENDPOINT_SIZE
813 || data->hs_desc.bDescriptorType
814 != USB_DT_ENDPOINT) {
815 DBG(data->dev, "config %s, bad hs length or type\n",
816 data->name);
817 goto fail0;
818 }
819 }
820
821 spin_lock_irq (&data->dev->lock);
822 if (data->dev->state == STATE_DEV_UNBOUND) {
823 value = -ENOENT;
824 goto gone;
825 } else if ((ep = data->ep) == NULL) {
826 value = -ENODEV;
827 goto gone;
828 }
829 switch (data->dev->gadget->speed) {
830 case USB_SPEED_LOW:
831 case USB_SPEED_FULL:
832 value = usb_ep_enable (ep, &data->desc);
833 if (value == 0)
834 data->state = STATE_EP_ENABLED;
835 break;
836 #ifdef CONFIG_USB_GADGET_DUALSPEED
837 case USB_SPEED_HIGH:
838 /* fails if caller didn't provide that descriptor... */
839 value = usb_ep_enable (ep, &data->hs_desc);
840 if (value == 0)
841 data->state = STATE_EP_ENABLED;
842 break;
843 #endif
844 default:
845 DBG(data->dev, "unconnected, %s init abandoned\n",
846 data->name);
847 value = -EINVAL;
848 }
849 if (value == 0) {
850 fd->f_op = &ep_io_operations;
851 value = length;
852 }
853 gone:
854 spin_unlock_irq (&data->dev->lock);
855 if (value < 0) {
856 fail:
857 data->desc.bDescriptorType = 0;
858 data->hs_desc.bDescriptorType = 0;
859 }
860 up (&data->lock);
861 return value;
862 fail0:
863 value = -EINVAL;
864 goto fail;
865 fail1:
866 value = -EFAULT;
867 goto fail;
868 }
869
870 static int
871 ep_open (struct inode *inode, struct file *fd)
872 {
873 struct ep_data *data = inode->i_private;
874 int value = -EBUSY;
875
876 if (down_interruptible (&data->lock) != 0)
877 return -EINTR;
878 spin_lock_irq (&data->dev->lock);
879 if (data->dev->state == STATE_DEV_UNBOUND)
880 value = -ENOENT;
881 else if (data->state == STATE_EP_DISABLED) {
882 value = 0;
883 data->state = STATE_EP_READY;
884 get_ep (data);
885 fd->private_data = data;
886 VDEBUG (data->dev, "%s ready\n", data->name);
887 } else
888 DBG (data->dev, "%s state %d\n",
889 data->name, data->state);
890 spin_unlock_irq (&data->dev->lock);
891 up (&data->lock);
892 return value;
893 }
894
895 /* used before endpoint configuration */
896 static const struct file_operations ep_config_operations = {
897 .owner = THIS_MODULE,
898 .llseek = no_llseek,
899
900 .open = ep_open,
901 .write = ep_config,
902 .release = ep_release,
903 };
904
905 /*----------------------------------------------------------------------*/
906
907 /* EP0 IMPLEMENTATION can be partly in userspace.
908 *
909 * Drivers that use this facility receive various events, including
910 * control requests the kernel doesn't handle. Drivers that don't
911 * use this facility may be too simple-minded for real applications.
912 */
913
914 static inline void ep0_readable (struct dev_data *dev)
915 {
916 wake_up (&dev->wait);
917 kill_fasync (&dev->fasync, SIGIO, POLL_IN);
918 }
919
920 static void clean_req (struct usb_ep *ep, struct usb_request *req)
921 {
922 struct dev_data *dev = ep->driver_data;
923
924 if (req->buf != dev->rbuf) {
925 kfree(req->buf);
926 req->buf = dev->rbuf;
927 req->dma = DMA_ADDR_INVALID;
928 }
929 req->complete = epio_complete;
930 dev->setup_out_ready = 0;
931 }
932
933 static void ep0_complete (struct usb_ep *ep, struct usb_request *req)
934 {
935 struct dev_data *dev = ep->driver_data;
936 unsigned long flags;
937 int free = 1;
938
939 /* for control OUT, data must still get to userspace */
940 spin_lock_irqsave(&dev->lock, flags);
941 if (!dev->setup_in) {
942 dev->setup_out_error = (req->status != 0);
943 if (!dev->setup_out_error)
944 free = 0;
945 dev->setup_out_ready = 1;
946 ep0_readable (dev);
947 }
948
949 /* clean up as appropriate */
950 if (free && req->buf != &dev->rbuf)
951 clean_req (ep, req);
952 req->complete = epio_complete;
953 spin_unlock_irqrestore(&dev->lock, flags);
954 }
955
956 static int setup_req (struct usb_ep *ep, struct usb_request *req, u16 len)
957 {
958 struct dev_data *dev = ep->driver_data;
959
960 if (dev->setup_out_ready) {
961 DBG (dev, "ep0 request busy!\n");
962 return -EBUSY;
963 }
964 if (len > sizeof (dev->rbuf))
965 req->buf = kmalloc(len, GFP_ATOMIC);
966 if (req->buf == NULL) {
967 req->buf = dev->rbuf;
968 return -ENOMEM;
969 }
970 req->complete = ep0_complete;
971 req->length = len;
972 req->zero = 0;
973 return 0;
974 }
975
976 static ssize_t
977 ep0_read (struct file *fd, char __user *buf, size_t len, loff_t *ptr)
978 {
979 struct dev_data *dev = fd->private_data;
980 ssize_t retval;
981 enum ep0_state state;
982
983 spin_lock_irq (&dev->lock);
984
985 /* report fd mode change before acting on it */
986 if (dev->setup_abort) {
987 dev->setup_abort = 0;
988 retval = -EIDRM;
989 goto done;
990 }
991
992 /* control DATA stage */
993 if ((state = dev->state) == STATE_DEV_SETUP) {
994
995 if (dev->setup_in) { /* stall IN */
996 VDEBUG(dev, "ep0in stall\n");
997 (void) usb_ep_set_halt (dev->gadget->ep0);
998 retval = -EL2HLT;
999 dev->state = STATE_DEV_CONNECTED;
1000
1001 } else if (len == 0) { /* ack SET_CONFIGURATION etc */
1002 struct usb_ep *ep = dev->gadget->ep0;
1003 struct usb_request *req = dev->req;
1004
1005 if ((retval = setup_req (ep, req, 0)) == 0)
1006 retval = usb_ep_queue (ep, req, GFP_ATOMIC);
1007 dev->state = STATE_DEV_CONNECTED;
1008
1009 /* assume that was SET_CONFIGURATION */
1010 if (dev->current_config) {
1011 unsigned power;
1012
1013 if (gadget_is_dualspeed(dev->gadget)
1014 && (dev->gadget->speed
1015 == USB_SPEED_HIGH))
1016 power = dev->hs_config->bMaxPower;
1017 else
1018 power = dev->config->bMaxPower;
1019 usb_gadget_vbus_draw(dev->gadget, 2 * power);
1020 }
1021
1022 } else { /* collect OUT data */
1023 if ((fd->f_flags & O_NONBLOCK) != 0
1024 && !dev->setup_out_ready) {
1025 retval = -EAGAIN;
1026 goto done;
1027 }
1028 spin_unlock_irq (&dev->lock);
1029 retval = wait_event_interruptible (dev->wait,
1030 dev->setup_out_ready != 0);
1031
1032 /* FIXME state could change from under us */
1033 spin_lock_irq (&dev->lock);
1034 if (retval)
1035 goto done;
1036
1037 if (dev->state != STATE_DEV_SETUP) {
1038 retval = -ECANCELED;
1039 goto done;
1040 }
1041 dev->state = STATE_DEV_CONNECTED;
1042
1043 if (dev->setup_out_error)
1044 retval = -EIO;
1045 else {
1046 len = min (len, (size_t)dev->req->actual);
1047 // FIXME don't call this with the spinlock held ...
1048 if (copy_to_user (buf, dev->req->buf, len))
1049 retval = -EFAULT;
1050 clean_req (dev->gadget->ep0, dev->req);
1051 /* NOTE userspace can't yet choose to stall */
1052 }
1053 }
1054 goto done;
1055 }
1056
1057 /* else normal: return event data */
1058 if (len < sizeof dev->event [0]) {
1059 retval = -EINVAL;
1060 goto done;
1061 }
1062 len -= len % sizeof (struct usb_gadgetfs_event);
1063 dev->usermode_setup = 1;
1064
1065 scan:
1066 /* return queued events right away */
1067 if (dev->ev_next != 0) {
1068 unsigned i, n;
1069
1070 n = len / sizeof (struct usb_gadgetfs_event);
1071 if (dev->ev_next < n)
1072 n = dev->ev_next;
1073
1074 /* ep0 i/o has special semantics during STATE_DEV_SETUP */
1075 for (i = 0; i < n; i++) {
1076 if (dev->event [i].type == GADGETFS_SETUP) {
1077 dev->state = STATE_DEV_SETUP;
1078 n = i + 1;
1079 break;
1080 }
1081 }
1082 spin_unlock_irq (&dev->lock);
1083 len = n * sizeof (struct usb_gadgetfs_event);
1084 if (copy_to_user (buf, &dev->event, len))
1085 retval = -EFAULT;
1086 else
1087 retval = len;
1088 if (len > 0) {
1089 /* NOTE this doesn't guard against broken drivers;
1090 * concurrent ep0 readers may lose events.
1091 */
1092 spin_lock_irq (&dev->lock);
1093 if (dev->ev_next > n) {
1094 memmove(&dev->event[0], &dev->event[n],
1095 sizeof (struct usb_gadgetfs_event)
1096 * (dev->ev_next - n));
1097 }
1098 dev->ev_next -= n;
1099 spin_unlock_irq (&dev->lock);
1100 }
1101 return retval;
1102 }
1103 if (fd->f_flags & O_NONBLOCK) {
1104 retval = -EAGAIN;
1105 goto done;
1106 }
1107
1108 switch (state) {
1109 default:
1110 DBG (dev, "fail %s, state %d\n", __FUNCTION__, state);
1111 retval = -ESRCH;
1112 break;
1113 case STATE_DEV_UNCONNECTED:
1114 case STATE_DEV_CONNECTED:
1115 spin_unlock_irq (&dev->lock);
1116 DBG (dev, "%s wait\n", __FUNCTION__);
1117
1118 /* wait for events */
1119 retval = wait_event_interruptible (dev->wait,
1120 dev->ev_next != 0);
1121 if (retval < 0)
1122 return retval;
1123 spin_lock_irq (&dev->lock);
1124 goto scan;
1125 }
1126
1127 done:
1128 spin_unlock_irq (&dev->lock);
1129 return retval;
1130 }
1131
1132 static struct usb_gadgetfs_event *
1133 next_event (struct dev_data *dev, enum usb_gadgetfs_event_type type)
1134 {
1135 struct usb_gadgetfs_event *event;
1136 unsigned i;
1137
1138 switch (type) {
1139 /* these events purge the queue */
1140 case GADGETFS_DISCONNECT:
1141 if (dev->state == STATE_DEV_SETUP)
1142 dev->setup_abort = 1;
1143 // FALL THROUGH
1144 case GADGETFS_CONNECT:
1145 dev->ev_next = 0;
1146 break;
1147 case GADGETFS_SETUP: /* previous request timed out */
1148 case GADGETFS_SUSPEND: /* same effect */
1149 /* these events can't be repeated */
1150 for (i = 0; i != dev->ev_next; i++) {
1151 if (dev->event [i].type != type)
1152 continue;
1153 DBG(dev, "discard old event[%d] %d\n", i, type);
1154 dev->ev_next--;
1155 if (i == dev->ev_next)
1156 break;
1157 /* indices start at zero, for simplicity */
1158 memmove (&dev->event [i], &dev->event [i + 1],
1159 sizeof (struct usb_gadgetfs_event)
1160 * (dev->ev_next - i));
1161 }
1162 break;
1163 default:
1164 BUG ();
1165 }
1166 VDEBUG(dev, "event[%d] = %d\n", dev->ev_next, type);
1167 event = &dev->event [dev->ev_next++];
1168 BUG_ON (dev->ev_next > N_EVENT);
1169 memset (event, 0, sizeof *event);
1170 event->type = type;
1171 return event;
1172 }
1173
1174 static ssize_t
1175 ep0_write (struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
1176 {
1177 struct dev_data *dev = fd->private_data;
1178 ssize_t retval = -ESRCH;
1179
1180 spin_lock_irq (&dev->lock);
1181
1182 /* report fd mode change before acting on it */
1183 if (dev->setup_abort) {
1184 dev->setup_abort = 0;
1185 retval = -EIDRM;
1186
1187 /* data and/or status stage for control request */
1188 } else if (dev->state == STATE_DEV_SETUP) {
1189
1190 /* IN DATA+STATUS caller makes len <= wLength */
1191 if (dev->setup_in) {
1192 retval = setup_req (dev->gadget->ep0, dev->req, len);
1193 if (retval == 0) {
1194 dev->state = STATE_DEV_CONNECTED;
1195 spin_unlock_irq (&dev->lock);
1196 if (copy_from_user (dev->req->buf, buf, len))
1197 retval = -EFAULT;
1198 else {
1199 if (len < dev->setup_wLength)
1200 dev->req->zero = 1;
1201 retval = usb_ep_queue (
1202 dev->gadget->ep0, dev->req,
1203 GFP_KERNEL);
1204 }
1205 if (retval < 0) {
1206 spin_lock_irq (&dev->lock);
1207 clean_req (dev->gadget->ep0, dev->req);
1208 spin_unlock_irq (&dev->lock);
1209 } else
1210 retval = len;
1211
1212 return retval;
1213 }
1214
1215 /* can stall some OUT transfers */
1216 } else if (dev->setup_can_stall) {
1217 VDEBUG(dev, "ep0out stall\n");
1218 (void) usb_ep_set_halt (dev->gadget->ep0);
1219 retval = -EL2HLT;
1220 dev->state = STATE_DEV_CONNECTED;
1221 } else {
1222 DBG(dev, "bogus ep0out stall!\n");
1223 }
1224 } else
1225 DBG (dev, "fail %s, state %d\n", __FUNCTION__, dev->state);
1226
1227 spin_unlock_irq (&dev->lock);
1228 return retval;
1229 }
1230
1231 static int
1232 ep0_fasync (int f, struct file *fd, int on)
1233 {
1234 struct dev_data *dev = fd->private_data;
1235 // caller must F_SETOWN before signal delivery happens
1236 VDEBUG (dev, "%s %s\n", __FUNCTION__, on ? "on" : "off");
1237 return fasync_helper (f, fd, on, &dev->fasync);
1238 }
1239
1240 static struct usb_gadget_driver gadgetfs_driver;
1241
1242 static int
1243 dev_release (struct inode *inode, struct file *fd)
1244 {
1245 struct dev_data *dev = fd->private_data;
1246
1247 /* closing ep0 === shutdown all */
1248
1249 usb_gadget_unregister_driver (&gadgetfs_driver);
1250
1251 /* at this point "good" hardware has disconnected the
1252 * device from USB; the host won't see it any more.
1253 * alternatively, all host requests will time out.
1254 */
1255
1256 fasync_helper (-1, fd, 0, &dev->fasync);
1257 kfree (dev->buf);
1258 dev->buf = NULL;
1259 put_dev (dev);
1260
1261 /* other endpoints were all decoupled from this device */
1262 spin_lock_irq(&dev->lock);
1263 dev->state = STATE_DEV_DISABLED;
1264 spin_unlock_irq(&dev->lock);
1265 return 0;
1266 }
1267
1268 static unsigned int
1269 ep0_poll (struct file *fd, poll_table *wait)
1270 {
1271 struct dev_data *dev = fd->private_data;
1272 int mask = 0;
1273
1274 poll_wait(fd, &dev->wait, wait);
1275
1276 spin_lock_irq (&dev->lock);
1277
1278 /* report fd mode change before acting on it */
1279 if (dev->setup_abort) {
1280 dev->setup_abort = 0;
1281 mask = POLLHUP;
1282 goto out;
1283 }
1284
1285 if (dev->state == STATE_DEV_SETUP) {
1286 if (dev->setup_in || dev->setup_can_stall)
1287 mask = POLLOUT;
1288 } else {
1289 if (dev->ev_next != 0)
1290 mask = POLLIN;
1291 }
1292 out:
1293 spin_unlock_irq(&dev->lock);
1294 return mask;
1295 }
1296
1297 static int dev_ioctl (struct inode *inode, struct file *fd,
1298 unsigned code, unsigned long value)
1299 {
1300 struct dev_data *dev = fd->private_data;
1301 struct usb_gadget *gadget = dev->gadget;
1302
1303 if (gadget->ops->ioctl)
1304 return gadget->ops->ioctl (gadget, code, value);
1305 return -ENOTTY;
1306 }
1307
1308 /* used after device configuration */
1309 static const struct file_operations ep0_io_operations = {
1310 .owner = THIS_MODULE,
1311 .llseek = no_llseek,
1312
1313 .read = ep0_read,
1314 .write = ep0_write,
1315 .fasync = ep0_fasync,
1316 .poll = ep0_poll,
1317 .ioctl = dev_ioctl,
1318 .release = dev_release,
1319 };
1320
1321 /*----------------------------------------------------------------------*/
1322
1323 /* The in-kernel gadget driver handles most ep0 issues, in particular
1324 * enumerating the single configuration (as provided from user space).
1325 *
1326 * Unrecognized ep0 requests may be handled in user space.
1327 */
1328
1329 #ifdef CONFIG_USB_GADGET_DUALSPEED
1330 static void make_qualifier (struct dev_data *dev)
1331 {
1332 struct usb_qualifier_descriptor qual;
1333 struct usb_device_descriptor *desc;
1334
1335 qual.bLength = sizeof qual;
1336 qual.bDescriptorType = USB_DT_DEVICE_QUALIFIER;
1337 qual.bcdUSB = __constant_cpu_to_le16 (0x0200);
1338
1339 desc = dev->dev;
1340 qual.bDeviceClass = desc->bDeviceClass;
1341 qual.bDeviceSubClass = desc->bDeviceSubClass;
1342 qual.bDeviceProtocol = desc->bDeviceProtocol;
1343
1344 /* assumes ep0 uses the same value for both speeds ... */
1345 qual.bMaxPacketSize0 = desc->bMaxPacketSize0;
1346
1347 qual.bNumConfigurations = 1;
1348 qual.bRESERVED = 0;
1349
1350 memcpy (dev->rbuf, &qual, sizeof qual);
1351 }
1352 #endif
1353
1354 static int
1355 config_buf (struct dev_data *dev, u8 type, unsigned index)
1356 {
1357 int len;
1358 int hs = 0;
1359
1360 /* only one configuration */
1361 if (index > 0)
1362 return -EINVAL;
1363
1364 if (gadget_is_dualspeed(dev->gadget)) {
1365 hs = (dev->gadget->speed == USB_SPEED_HIGH);
1366 if (type == USB_DT_OTHER_SPEED_CONFIG)
1367 hs = !hs;
1368 }
1369 if (hs) {
1370 dev->req->buf = dev->hs_config;
1371 len = le16_to_cpu(dev->hs_config->wTotalLength);
1372 } else {
1373 dev->req->buf = dev->config;
1374 len = le16_to_cpu(dev->config->wTotalLength);
1375 }
1376 ((u8 *)dev->req->buf) [1] = type;
1377 return len;
1378 }
1379
1380 static int
1381 gadgetfs_setup (struct usb_gadget *gadget, const struct usb_ctrlrequest *ctrl)
1382 {
1383 struct dev_data *dev = get_gadget_data (gadget);
1384 struct usb_request *req = dev->req;
1385 int value = -EOPNOTSUPP;
1386 struct usb_gadgetfs_event *event;
1387 u16 w_value = le16_to_cpu(ctrl->wValue);
1388 u16 w_length = le16_to_cpu(ctrl->wLength);
1389
1390 spin_lock (&dev->lock);
1391 dev->setup_abort = 0;
1392 if (dev->state == STATE_DEV_UNCONNECTED) {
1393 if (gadget_is_dualspeed(gadget)
1394 && gadget->speed == USB_SPEED_HIGH
1395 && dev->hs_config == NULL) {
1396 spin_unlock(&dev->lock);
1397 ERROR (dev, "no high speed config??\n");
1398 return -EINVAL;
1399 }
1400
1401 dev->state = STATE_DEV_CONNECTED;
1402 dev->dev->bMaxPacketSize0 = gadget->ep0->maxpacket;
1403
1404 INFO (dev, "connected\n");
1405 event = next_event (dev, GADGETFS_CONNECT);
1406 event->u.speed = gadget->speed;
1407 ep0_readable (dev);
1408
1409 /* host may have given up waiting for response. we can miss control
1410 * requests handled lower down (device/endpoint status and features);
1411 * then ep0_{read,write} will report the wrong status. controller
1412 * driver will have aborted pending i/o.
1413 */
1414 } else if (dev->state == STATE_DEV_SETUP)
1415 dev->setup_abort = 1;
1416
1417 req->buf = dev->rbuf;
1418 req->dma = DMA_ADDR_INVALID;
1419 req->context = NULL;
1420 value = -EOPNOTSUPP;
1421 switch (ctrl->bRequest) {
1422
1423 case USB_REQ_GET_DESCRIPTOR:
1424 if (ctrl->bRequestType != USB_DIR_IN)
1425 goto unrecognized;
1426 switch (w_value >> 8) {
1427
1428 case USB_DT_DEVICE:
1429 value = min (w_length, (u16) sizeof *dev->dev);
1430 req->buf = dev->dev;
1431 break;
1432 #ifdef CONFIG_USB_GADGET_DUALSPEED
1433 case USB_DT_DEVICE_QUALIFIER:
1434 if (!dev->hs_config)
1435 break;
1436 value = min (w_length, (u16)
1437 sizeof (struct usb_qualifier_descriptor));
1438 make_qualifier (dev);
1439 break;
1440 case USB_DT_OTHER_SPEED_CONFIG:
1441 // FALLTHROUGH
1442 #endif
1443 case USB_DT_CONFIG:
1444 value = config_buf (dev,
1445 w_value >> 8,
1446 w_value & 0xff);
1447 if (value >= 0)
1448 value = min (w_length, (u16) value);
1449 break;
1450 case USB_DT_STRING:
1451 goto unrecognized;
1452
1453 default: // all others are errors
1454 break;
1455 }
1456 break;
1457
1458 /* currently one config, two speeds */
1459 case USB_REQ_SET_CONFIGURATION:
1460 if (ctrl->bRequestType != 0)
1461 goto unrecognized;
1462 if (0 == (u8) w_value) {
1463 value = 0;
1464 dev->current_config = 0;
1465 usb_gadget_vbus_draw(gadget, 8 /* mA */ );
1466 // user mode expected to disable endpoints
1467 } else {
1468 u8 config, power;
1469
1470 if (gadget_is_dualspeed(gadget)
1471 && gadget->speed == USB_SPEED_HIGH) {
1472 config = dev->hs_config->bConfigurationValue;
1473 power = dev->hs_config->bMaxPower;
1474 } else {
1475 config = dev->config->bConfigurationValue;
1476 power = dev->config->bMaxPower;
1477 }
1478
1479 if (config == (u8) w_value) {
1480 value = 0;
1481 dev->current_config = config;
1482 usb_gadget_vbus_draw(gadget, 2 * power);
1483 }
1484 }
1485
1486 /* report SET_CONFIGURATION like any other control request,
1487 * except that usermode may not stall this. the next
1488 * request mustn't be allowed start until this finishes:
1489 * endpoints and threads set up, etc.
1490 *
1491 * NOTE: older PXA hardware (before PXA 255: without UDCCFR)
1492 * has bad/racey automagic that prevents synchronizing here.
1493 * even kernel mode drivers often miss them.
1494 */
1495 if (value == 0) {
1496 INFO (dev, "configuration #%d\n", dev->current_config);
1497 if (dev->usermode_setup) {
1498 dev->setup_can_stall = 0;
1499 goto delegate;
1500 }
1501 }
1502 break;
1503
1504 #ifndef CONFIG_USB_GADGET_PXA2XX
1505 /* PXA automagically handles this request too */
1506 case USB_REQ_GET_CONFIGURATION:
1507 if (ctrl->bRequestType != 0x80)
1508 goto unrecognized;
1509 *(u8 *)req->buf = dev->current_config;
1510 value = min (w_length, (u16) 1);
1511 break;
1512 #endif
1513
1514 default:
1515 unrecognized:
1516 VDEBUG (dev, "%s req%02x.%02x v%04x i%04x l%d\n",
1517 dev->usermode_setup ? "delegate" : "fail",
1518 ctrl->bRequestType, ctrl->bRequest,
1519 w_value, le16_to_cpu(ctrl->wIndex), w_length);
1520
1521 /* if there's an ep0 reader, don't stall */
1522 if (dev->usermode_setup) {
1523 dev->setup_can_stall = 1;
1524 delegate:
1525 dev->setup_in = (ctrl->bRequestType & USB_DIR_IN)
1526 ? 1 : 0;
1527 dev->setup_wLength = w_length;
1528 dev->setup_out_ready = 0;
1529 dev->setup_out_error = 0;
1530 value = 0;
1531
1532 /* read DATA stage for OUT right away */
1533 if (unlikely (!dev->setup_in && w_length)) {
1534 value = setup_req (gadget->ep0, dev->req,
1535 w_length);
1536 if (value < 0)
1537 break;
1538 value = usb_ep_queue (gadget->ep0, dev->req,
1539 GFP_ATOMIC);
1540 if (value < 0) {
1541 clean_req (gadget->ep0, dev->req);
1542 break;
1543 }
1544
1545 /* we can't currently stall these */
1546 dev->setup_can_stall = 0;
1547 }
1548
1549 /* state changes when reader collects event */
1550 event = next_event (dev, GADGETFS_SETUP);
1551 event->u.setup = *ctrl;
1552 ep0_readable (dev);
1553 spin_unlock (&dev->lock);
1554 return 0;
1555 }
1556 }
1557
1558 /* proceed with data transfer and status phases? */
1559 if (value >= 0 && dev->state != STATE_DEV_SETUP) {
1560 req->length = value;
1561 req->zero = value < w_length;
1562 value = usb_ep_queue (gadget->ep0, req, GFP_ATOMIC);
1563 if (value < 0) {
1564 DBG (dev, "ep_queue --> %d\n", value);
1565 req->status = 0;
1566 }
1567 }
1568
1569 /* device stalls when value < 0 */
1570 spin_unlock (&dev->lock);
1571 return value;
1572 }
1573
1574 static void destroy_ep_files (struct dev_data *dev)
1575 {
1576 struct list_head *entry, *tmp;
1577
1578 DBG (dev, "%s %d\n", __FUNCTION__, dev->state);
1579
1580 /* dev->state must prevent interference */
1581 restart:
1582 spin_lock_irq (&dev->lock);
1583 list_for_each_safe (entry, tmp, &dev->epfiles) {
1584 struct ep_data *ep;
1585 struct inode *parent;
1586 struct dentry *dentry;
1587
1588 /* break link to FS */
1589 ep = list_entry (entry, struct ep_data, epfiles);
1590 list_del_init (&ep->epfiles);
1591 dentry = ep->dentry;
1592 ep->dentry = NULL;
1593 parent = dentry->d_parent->d_inode;
1594
1595 /* break link to controller */
1596 if (ep->state == STATE_EP_ENABLED)
1597 (void) usb_ep_disable (ep->ep);
1598 ep->state = STATE_EP_UNBOUND;
1599 usb_ep_free_request (ep->ep, ep->req);
1600 ep->ep = NULL;
1601 wake_up (&ep->wait);
1602 put_ep (ep);
1603
1604 spin_unlock_irq (&dev->lock);
1605
1606 /* break link to dcache */
1607 mutex_lock (&parent->i_mutex);
1608 d_delete (dentry);
1609 dput (dentry);
1610 mutex_unlock (&parent->i_mutex);
1611
1612 /* fds may still be open */
1613 goto restart;
1614 }
1615 spin_unlock_irq (&dev->lock);
1616 }
1617
1618
1619 static struct inode *
1620 gadgetfs_create_file (struct super_block *sb, char const *name,
1621 void *data, const struct file_operations *fops,
1622 struct dentry **dentry_p);
1623
1624 static int activate_ep_files (struct dev_data *dev)
1625 {
1626 struct usb_ep *ep;
1627 struct ep_data *data;
1628
1629 gadget_for_each_ep (ep, dev->gadget) {
1630
1631 data = kzalloc(sizeof(*data), GFP_KERNEL);
1632 if (!data)
1633 goto enomem0;
1634 data->state = STATE_EP_DISABLED;
1635 init_MUTEX (&data->lock);
1636 init_waitqueue_head (&data->wait);
1637
1638 strncpy (data->name, ep->name, sizeof (data->name) - 1);
1639 atomic_set (&data->count, 1);
1640 data->dev = dev;
1641 get_dev (dev);
1642
1643 data->ep = ep;
1644 ep->driver_data = data;
1645
1646 data->req = usb_ep_alloc_request (ep, GFP_KERNEL);
1647 if (!data->req)
1648 goto enomem1;
1649
1650 data->inode = gadgetfs_create_file (dev->sb, data->name,
1651 data, &ep_config_operations,
1652 &data->dentry);
1653 if (!data->inode)
1654 goto enomem2;
1655 list_add_tail (&data->epfiles, &dev->epfiles);
1656 }
1657 return 0;
1658
1659 enomem2:
1660 usb_ep_free_request (ep, data->req);
1661 enomem1:
1662 put_dev (dev);
1663 kfree (data);
1664 enomem0:
1665 DBG (dev, "%s enomem\n", __FUNCTION__);
1666 destroy_ep_files (dev);
1667 return -ENOMEM;
1668 }
1669
1670 static void
1671 gadgetfs_unbind (struct usb_gadget *gadget)
1672 {
1673 struct dev_data *dev = get_gadget_data (gadget);
1674
1675 DBG (dev, "%s\n", __FUNCTION__);
1676
1677 spin_lock_irq (&dev->lock);
1678 dev->state = STATE_DEV_UNBOUND;
1679 spin_unlock_irq (&dev->lock);
1680
1681 destroy_ep_files (dev);
1682 gadget->ep0->driver_data = NULL;
1683 set_gadget_data (gadget, NULL);
1684
1685 /* we've already been disconnected ... no i/o is active */
1686 if (dev->req)
1687 usb_ep_free_request (gadget->ep0, dev->req);
1688 DBG (dev, "%s done\n", __FUNCTION__);
1689 put_dev (dev);
1690 }
1691
1692 static struct dev_data *the_device;
1693
1694 static int
1695 gadgetfs_bind (struct usb_gadget *gadget)
1696 {
1697 struct dev_data *dev = the_device;
1698
1699 if (!dev)
1700 return -ESRCH;
1701 if (0 != strcmp (CHIP, gadget->name)) {
1702 pr_err("%s expected %s controller not %s\n",
1703 shortname, CHIP, gadget->name);
1704 return -ENODEV;
1705 }
1706
1707 set_gadget_data (gadget, dev);
1708 dev->gadget = gadget;
1709 gadget->ep0->driver_data = dev;
1710 dev->dev->bMaxPacketSize0 = gadget->ep0->maxpacket;
1711
1712 /* preallocate control response and buffer */
1713 dev->req = usb_ep_alloc_request (gadget->ep0, GFP_KERNEL);
1714 if (!dev->req)
1715 goto enomem;
1716 dev->req->context = NULL;
1717 dev->req->complete = epio_complete;
1718
1719 if (activate_ep_files (dev) < 0)
1720 goto enomem;
1721
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);
1726 get_dev (dev);
1727 return 0;
1728
1729 enomem:
1730 gadgetfs_unbind (gadget);
1731 return -ENOMEM;
1732 }
1733
1734 static void
1735 gadgetfs_disconnect (struct usb_gadget *gadget)
1736 {
1737 struct dev_data *dev = get_gadget_data (gadget);
1738
1739 spin_lock (&dev->lock);
1740 if (dev->state == STATE_DEV_UNCONNECTED)
1741 goto exit;
1742 dev->state = STATE_DEV_UNCONNECTED;
1743
1744 INFO (dev, "disconnected\n");
1745 next_event (dev, GADGETFS_DISCONNECT);
1746 ep0_readable (dev);
1747 exit:
1748 spin_unlock (&dev->lock);
1749 }
1750
1751 static void
1752 gadgetfs_suspend (struct usb_gadget *gadget)
1753 {
1754 struct dev_data *dev = get_gadget_data (gadget);
1755
1756 INFO (dev, "suspended from state %d\n", dev->state);
1757 spin_lock (&dev->lock);
1758 switch (dev->state) {
1759 case STATE_DEV_SETUP: // VERY odd... host died??
1760 case STATE_DEV_CONNECTED:
1761 case STATE_DEV_UNCONNECTED:
1762 next_event (dev, GADGETFS_SUSPEND);
1763 ep0_readable (dev);
1764 /* FALLTHROUGH */
1765 default:
1766 break;
1767 }
1768 spin_unlock (&dev->lock);
1769 }
1770
1771 static struct usb_gadget_driver gadgetfs_driver = {
1772 #ifdef CONFIG_USB_GADGET_DUALSPEED
1773 .speed = USB_SPEED_HIGH,
1774 #else
1775 .speed = USB_SPEED_FULL,
1776 #endif
1777 .function = (char *) driver_desc,
1778 .bind = gadgetfs_bind,
1779 .unbind = gadgetfs_unbind,
1780 .setup = gadgetfs_setup,
1781 .disconnect = gadgetfs_disconnect,
1782 .suspend = gadgetfs_suspend,
1783
1784 .driver = {
1785 .name = (char *) shortname,
1786 },
1787 };
1788
1789 /*----------------------------------------------------------------------*/
1790
1791 static void gadgetfs_nop(struct usb_gadget *arg) { }
1792
1793 static int gadgetfs_probe (struct usb_gadget *gadget)
1794 {
1795 CHIP = gadget->name;
1796 return -EISNAM;
1797 }
1798
1799 static struct usb_gadget_driver probe_driver = {
1800 .speed = USB_SPEED_HIGH,
1801 .bind = gadgetfs_probe,
1802 .unbind = gadgetfs_nop,
1803 .setup = (void *)gadgetfs_nop,
1804 .disconnect = gadgetfs_nop,
1805 .driver = {
1806 .name = "nop",
1807 },
1808 };
1809
1810
1811 /* DEVICE INITIALIZATION
1812 *
1813 * fd = open ("/dev/gadget/$CHIP", O_RDWR)
1814 * status = write (fd, descriptors, sizeof descriptors)
1815 *
1816 * That write establishes the device configuration, so the kernel can
1817 * bind to the controller ... guaranteeing it can handle enumeration
1818 * at all necessary speeds. Descriptor order is:
1819 *
1820 * . message tag (u32, host order) ... for now, must be zero; it
1821 * would change to support features like multi-config devices
1822 * . full/low speed config ... all wTotalLength bytes (with interface,
1823 * class, altsetting, endpoint, and other descriptors)
1824 * . high speed config ... all descriptors, for high speed operation;
1825 * this one's optional except for high-speed hardware
1826 * . device descriptor
1827 *
1828 * Endpoints are not yet enabled. Drivers must wait until device
1829 * configuration and interface altsetting changes create
1830 * the need to configure (or unconfigure) them.
1831 *
1832 * After initialization, the device stays active for as long as that
1833 * $CHIP file is open. Events must then be read from that descriptor,
1834 * such as configuration notifications.
1835 */
1836
1837 static int is_valid_config (struct usb_config_descriptor *config)
1838 {
1839 return config->bDescriptorType == USB_DT_CONFIG
1840 && config->bLength == USB_DT_CONFIG_SIZE
1841 && config->bConfigurationValue != 0
1842 && (config->bmAttributes & USB_CONFIG_ATT_ONE) != 0
1843 && (config->bmAttributes & USB_CONFIG_ATT_WAKEUP) == 0;
1844 /* FIXME if gadget->is_otg, _must_ include an otg descriptor */
1845 /* FIXME check lengths: walk to end */
1846 }
1847
1848 static ssize_t
1849 dev_config (struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
1850 {
1851 struct dev_data *dev = fd->private_data;
1852 ssize_t value = len, length = len;
1853 unsigned total;
1854 u32 tag;
1855 char *kbuf;
1856
1857 if (len < (USB_DT_CONFIG_SIZE + USB_DT_DEVICE_SIZE + 4))
1858 return -EINVAL;
1859
1860 /* we might need to change message format someday */
1861 if (copy_from_user (&tag, buf, 4))
1862 return -EFAULT;
1863 if (tag != 0)
1864 return -EINVAL;
1865 buf += 4;
1866 length -= 4;
1867
1868 kbuf = kmalloc (length, GFP_KERNEL);
1869 if (!kbuf)
1870 return -ENOMEM;
1871 if (copy_from_user (kbuf, buf, length)) {
1872 kfree (kbuf);
1873 return -EFAULT;
1874 }
1875
1876 spin_lock_irq (&dev->lock);
1877 value = -EINVAL;
1878 if (dev->buf)
1879 goto fail;
1880 dev->buf = kbuf;
1881
1882 /* full or low speed config */
1883 dev->config = (void *) kbuf;
1884 total = le16_to_cpu(dev->config->wTotalLength);
1885 if (!is_valid_config (dev->config) || total >= length)
1886 goto fail;
1887 kbuf += total;
1888 length -= total;
1889
1890 /* optional high speed config */
1891 if (kbuf [1] == USB_DT_CONFIG) {
1892 dev->hs_config = (void *) kbuf;
1893 total = le16_to_cpu(dev->hs_config->wTotalLength);
1894 if (!is_valid_config (dev->hs_config) || total >= length)
1895 goto fail;
1896 kbuf += total;
1897 length -= total;
1898 }
1899
1900 /* could support multiple configs, using another encoding! */
1901
1902 /* device descriptor (tweaked for paranoia) */
1903 if (length != USB_DT_DEVICE_SIZE)
1904 goto fail;
1905 dev->dev = (void *)kbuf;
1906 if (dev->dev->bLength != USB_DT_DEVICE_SIZE
1907 || dev->dev->bDescriptorType != USB_DT_DEVICE
1908 || dev->dev->bNumConfigurations != 1)
1909 goto fail;
1910 dev->dev->bNumConfigurations = 1;
1911 dev->dev->bcdUSB = __constant_cpu_to_le16 (0x0200);
1912
1913 /* triggers gadgetfs_bind(); then we can enumerate. */
1914 spin_unlock_irq (&dev->lock);
1915 value = usb_gadget_register_driver (&gadgetfs_driver);
1916 if (value != 0) {
1917 kfree (dev->buf);
1918 dev->buf = NULL;
1919 } else {
1920 /* at this point "good" hardware has for the first time
1921 * let the USB the host see us. alternatively, if users
1922 * unplug/replug that will clear all the error state.
1923 *
1924 * note: everything running before here was guaranteed
1925 * to choke driver model style diagnostics. from here
1926 * on, they can work ... except in cleanup paths that
1927 * kick in after the ep0 descriptor is closed.
1928 */
1929 fd->f_op = &ep0_io_operations;
1930 value = len;
1931 }
1932 return value;
1933
1934 fail:
1935 spin_unlock_irq (&dev->lock);
1936 pr_debug ("%s: %s fail %Zd, %p\n", shortname, __FUNCTION__, value, dev);
1937 kfree (dev->buf);
1938 dev->buf = NULL;
1939 return value;
1940 }
1941
1942 static int
1943 dev_open (struct inode *inode, struct file *fd)
1944 {
1945 struct dev_data *dev = inode->i_private;
1946 int value = -EBUSY;
1947
1948 spin_lock_irq(&dev->lock);
1949 if (dev->state == STATE_DEV_DISABLED) {
1950 dev->ev_next = 0;
1951 dev->state = STATE_DEV_OPENED;
1952 fd->private_data = dev;
1953 get_dev (dev);
1954 value = 0;
1955 }
1956 spin_unlock_irq(&dev->lock);
1957 return value;
1958 }
1959
1960 static const struct file_operations dev_init_operations = {
1961 .owner = THIS_MODULE,
1962 .llseek = no_llseek,
1963
1964 .open = dev_open,
1965 .write = dev_config,
1966 .fasync = ep0_fasync,
1967 .ioctl = dev_ioctl,
1968 .release = dev_release,
1969 };
1970
1971 /*----------------------------------------------------------------------*/
1972
1973 /* FILESYSTEM AND SUPERBLOCK OPERATIONS
1974 *
1975 * Mounting the filesystem creates a controller file, used first for
1976 * device configuration then later for event monitoring.
1977 */
1978
1979
1980 /* FIXME PAM etc could set this security policy without mount options
1981 * if epfiles inherited ownership and permissons from ep0 ...
1982 */
1983
1984 static unsigned default_uid;
1985 static unsigned default_gid;
1986 static unsigned default_perm = S_IRUSR | S_IWUSR;
1987
1988 module_param (default_uid, uint, 0644);
1989 module_param (default_gid, uint, 0644);
1990 module_param (default_perm, uint, 0644);
1991
1992
1993 static struct inode *
1994 gadgetfs_make_inode (struct super_block *sb,
1995 void *data, const struct file_operations *fops,
1996 int mode)
1997 {
1998 struct inode *inode = new_inode (sb);
1999
2000 if (inode) {
2001 inode->i_mode = mode;
2002 inode->i_uid = default_uid;
2003 inode->i_gid = default_gid;
2004 inode->i_blocks = 0;
2005 inode->i_atime = inode->i_mtime = inode->i_ctime
2006 = CURRENT_TIME;
2007 inode->i_private = data;
2008 inode->i_fop = fops;
2009 }
2010 return inode;
2011 }
2012
2013 /* creates in fs root directory, so non-renamable and non-linkable.
2014 * so inode and dentry are paired, until device reconfig.
2015 */
2016 static struct inode *
2017 gadgetfs_create_file (struct super_block *sb, char const *name,
2018 void *data, const struct file_operations *fops,
2019 struct dentry **dentry_p)
2020 {
2021 struct dentry *dentry;
2022 struct inode *inode;
2023
2024 dentry = d_alloc_name(sb->s_root, name);
2025 if (!dentry)
2026 return NULL;
2027
2028 inode = gadgetfs_make_inode (sb, data, fops,
2029 S_IFREG | (default_perm & S_IRWXUGO));
2030 if (!inode) {
2031 dput(dentry);
2032 return NULL;
2033 }
2034 d_add (dentry, inode);
2035 *dentry_p = dentry;
2036 return inode;
2037 }
2038
2039 static struct super_operations gadget_fs_operations = {
2040 .statfs = simple_statfs,
2041 .drop_inode = generic_delete_inode,
2042 };
2043
2044 static int
2045 gadgetfs_fill_super (struct super_block *sb, void *opts, int silent)
2046 {
2047 struct inode *inode;
2048 struct dentry *d;
2049 struct dev_data *dev;
2050
2051 if (the_device)
2052 return -ESRCH;
2053
2054 /* fake probe to determine $CHIP */
2055 (void) usb_gadget_register_driver (&probe_driver);
2056 if (!CHIP)
2057 return -ENODEV;
2058
2059 /* superblock */
2060 sb->s_blocksize = PAGE_CACHE_SIZE;
2061 sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
2062 sb->s_magic = GADGETFS_MAGIC;
2063 sb->s_op = &gadget_fs_operations;
2064 sb->s_time_gran = 1;
2065
2066 /* root inode */
2067 inode = gadgetfs_make_inode (sb,
2068 NULL, &simple_dir_operations,
2069 S_IFDIR | S_IRUGO | S_IXUGO);
2070 if (!inode)
2071 goto enomem0;
2072 inode->i_op = &simple_dir_inode_operations;
2073 if (!(d = d_alloc_root (inode)))
2074 goto enomem1;
2075 sb->s_root = d;
2076
2077 /* the ep0 file is named after the controller we expect;
2078 * user mode code can use it for sanity checks, like we do.
2079 */
2080 dev = dev_new ();
2081 if (!dev)
2082 goto enomem2;
2083
2084 dev->sb = sb;
2085 if (!gadgetfs_create_file (sb, CHIP,
2086 dev, &dev_init_operations,
2087 &dev->dentry))
2088 goto enomem3;
2089
2090 /* other endpoint files are available after hardware setup,
2091 * from binding to a controller.
2092 */
2093 the_device = dev;
2094 return 0;
2095
2096 enomem3:
2097 put_dev (dev);
2098 enomem2:
2099 dput (d);
2100 enomem1:
2101 iput (inode);
2102 enomem0:
2103 return -ENOMEM;
2104 }
2105
2106 /* "mount -t gadgetfs path /dev/gadget" ends up here */
2107 static int
2108 gadgetfs_get_sb (struct file_system_type *t, int flags,
2109 const char *path, void *opts, struct vfsmount *mnt)
2110 {
2111 return get_sb_single (t, flags, opts, gadgetfs_fill_super, mnt);
2112 }
2113
2114 static void
2115 gadgetfs_kill_sb (struct super_block *sb)
2116 {
2117 kill_litter_super (sb);
2118 if (the_device) {
2119 put_dev (the_device);
2120 the_device = NULL;
2121 }
2122 }
2123
2124 /*----------------------------------------------------------------------*/
2125
2126 static struct file_system_type gadgetfs_type = {
2127 .owner = THIS_MODULE,
2128 .name = shortname,
2129 .get_sb = gadgetfs_get_sb,
2130 .kill_sb = gadgetfs_kill_sb,
2131 };
2132
2133 /*----------------------------------------------------------------------*/
2134
2135 static int __init init (void)
2136 {
2137 int status;
2138
2139 status = register_filesystem (&gadgetfs_type);
2140 if (status == 0)
2141 pr_info ("%s: %s, version " DRIVER_VERSION "\n",
2142 shortname, driver_desc);
2143 return status;
2144 }
2145 module_init (init);
2146
2147 static void __exit cleanup (void)
2148 {
2149 pr_debug ("unregister %s\n", shortname);
2150 unregister_filesystem (&gadgetfs_type);
2151 }
2152 module_exit (cleanup);
2153
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