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usb: gadgetfs remove delayed init mode
[linux-2.6.git] / drivers / usb / gadget / inode.c
blob0f00249720b3037492be30bf8698cd2a8a441950
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 DEBUG /* data to help fault diagnosis */
24 // #define VERBOSE /* extra debug messages (success too) */
25
26 #include <linux/init.h>
27 #include <linux/module.h>
28 #include <linux/fs.h>
29 #include <linux/pagemap.h>
30 #include <linux/uts.h>
31 #include <linux/wait.h>
32 #include <linux/compiler.h>
33 #include <asm/uaccess.h>
34 #include <linux/slab.h>
35 #include <linux/poll.h>
36
37 #include <linux/device.h>
38 #include <linux/moduleparam.h>
39
40 #include <linux/usb_gadgetfs.h>
41 #include <linux/usb_gadget.h>
42
43
44 /*
45 * The gadgetfs API maps each endpoint to a file descriptor so that you
46 * can use standard synchronous read/write calls for I/O. There's some
47 * O_NONBLOCK and O_ASYNC/FASYNC style i/o support. Example usermode
48 * drivers show how this works in practice. You can also use AIO to
49 * eliminate I/O gaps between requests, to help when streaming data.
50 *
51 * Key parts that must be USB-specific are protocols defining how the
52 * read/write operations relate to the hardware state machines. There
53 * are two types of files. One type is for the device, implementing ep0.
54 * The other type is for each IN or OUT endpoint. In both cases, the
55 * user mode driver must configure the hardware before using it.
56 *
57 * - First, dev_config() is called when /dev/gadget/$CHIP is configured
58 * (by writing configuration and device descriptors). Afterwards it
59 * may serve as a source of device events, used to handle all control
60 * requests other than basic enumeration.
61 *
62 * - Then, after a SET_CONFIGURATION control request, ep_config() is
63 * called when each /dev/gadget/ep* file is configured (by writing
64 * endpoint descriptors). Afterwards these files are used to write()
65 * IN data or to read() OUT data. To halt the endpoint, a "wrong
66 * direction" request is issued (like reading an IN endpoint).
67 *
68 * Unlike "usbfs" the only ioctl()s are for things that are rare, and maybe
69 * not possible on all hardware. For example, precise fault handling with
70 * respect to data left in endpoint fifos after aborted operations; or
71 * selective clearing of endpoint halts, to implement SET_INTERFACE.
72 */
73
74 #define DRIVER_DESC "USB Gadget filesystem"
75 #define DRIVER_VERSION "24 Aug 2004"
76
77 static const char driver_desc [] = DRIVER_DESC;
78 static const char shortname [] = "gadgetfs";
79
80 MODULE_DESCRIPTION (DRIVER_DESC);
81 MODULE_AUTHOR ("David Brownell");
82 MODULE_LICENSE ("GPL");
83
84
85 /*----------------------------------------------------------------------*/
86
87 #define GADGETFS_MAGIC 0xaee71ee7
88 #define DMA_ADDR_INVALID (~(dma_addr_t)0)
89
90 /* /dev/gadget/$CHIP represents ep0 and the whole device */
91 enum ep0_state {
92 /* DISBLED is the initial state.
93 */
94 STATE_DEV_DISABLED = 0,
95
96 /* Only one open() of /dev/gadget/$CHIP; only one file tracks
97 * ep0/device i/o modes and binding to the controller. Driver
98 * must always write descriptors to initialize the device, then
99 * the device becomes UNCONNECTED until enumeration.
100 */
101 STATE_OPENED,
102
103 /* From then on, ep0 fd is in either of two basic modes:
104 * - (UN)CONNECTED: read usb_gadgetfs_event(s) from it
105 * - SETUP: read/write will transfer control data and succeed;
106 * or if "wrong direction", performs protocol stall
107 */
108 STATE_UNCONNECTED,
109 STATE_CONNECTED,
110 STATE_SETUP,
111
112 /* UNBOUND means the driver closed ep0, so the device won't be
113 * accessible again (DEV_DISABLED) until all fds are closed.
114 */
115 STATE_DEV_UNBOUND,
116 };
117
118 /* enough for the whole queue: most events invalidate others */
119 #define N_EVENT 5
120
121 struct dev_data {
122 spinlock_t lock;
123 atomic_t count;
124 enum ep0_state state;
125 struct usb_gadgetfs_event event [N_EVENT];
126 unsigned ev_next;
127 struct fasync_struct *fasync;
128 u8 current_config;
129
130 /* drivers reading ep0 MUST handle control requests (SETUP)
131 * reported that way; else the host will time out.
132 */
133 unsigned usermode_setup : 1,
134 setup_in : 1,
135 setup_can_stall : 1,
136 setup_out_ready : 1,
137 setup_out_error : 1,
138 setup_abort : 1;
139 unsigned setup_wLength;
140
141 /* the rest is basically write-once */
142 struct usb_config_descriptor *config, *hs_config;
143 struct usb_device_descriptor *dev;
144 struct usb_request *req;
145 struct usb_gadget *gadget;
146 struct list_head epfiles;
147 void *buf;
148 wait_queue_head_t wait;
149 struct super_block *sb;
150 struct dentry *dentry;
151
152 /* except this scratch i/o buffer for ep0 */
153 u8 rbuf [256];
154 };
155
156 static inline void get_dev (struct dev_data *data)
157 {
158 atomic_inc (&data->count);
159 }
160
161 static void put_dev (struct dev_data *data)
162 {
163 if (likely (!atomic_dec_and_test (&data->count)))
164 return;
165 /* needs no more cleanup */
166 BUG_ON (waitqueue_active (&data->wait));
167 kfree (data);
168 }
169
170 static struct dev_data *dev_new (void)
171 {
172 struct dev_data *dev;
173
174 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
175 if (!dev)
176 return NULL;
177 dev->state = STATE_DEV_DISABLED;
178 atomic_set (&dev->count, 1);
179 spin_lock_init (&dev->lock);
180 INIT_LIST_HEAD (&dev->epfiles);
181 init_waitqueue_head (&dev->wait);
182 return dev;
183 }
184
185 /*----------------------------------------------------------------------*/
186
187 /* other /dev/gadget/$ENDPOINT files represent endpoints */
188 enum ep_state {
189 STATE_EP_DISABLED = 0,
190 STATE_EP_READY,
191 STATE_EP_ENABLED,
192 STATE_EP_UNBOUND,
193 };
194
195 struct ep_data {
196 struct semaphore lock;
197 enum ep_state state;
198 atomic_t count;
199 struct dev_data *dev;
200 /* must hold dev->lock before accessing ep or req */
201 struct usb_ep *ep;
202 struct usb_request *req;
203 ssize_t status;
204 char name [16];
205 struct usb_endpoint_descriptor desc, hs_desc;
206 struct list_head epfiles;
207 wait_queue_head_t wait;
208 struct dentry *dentry;
209 struct inode *inode;
210 };
211
212 static inline void get_ep (struct ep_data *data)
213 {
214 atomic_inc (&data->count);
215 }
216
217 static void put_ep (struct ep_data *data)
218 {
219 if (likely (!atomic_dec_and_test (&data->count)))
220 return;
221 put_dev (data->dev);
222 /* needs no more cleanup */
223 BUG_ON (!list_empty (&data->epfiles));
224 BUG_ON (waitqueue_active (&data->wait));
225 kfree (data);
226 }
227
228 /*----------------------------------------------------------------------*/
229
230 /* most "how to use the hardware" policy choices are in userspace:
231 * mapping endpoint roles (which the driver needs) to the capabilities
232 * which the usb controller has. most of those capabilities are exposed
233 * implicitly, starting with the driver name and then endpoint names.
234 */
235
236 static const char *CHIP;
237
238 /*----------------------------------------------------------------------*/
239
240 /* NOTE: don't use dev_printk calls before binding to the gadget
241 * at the end of ep0 configuration, or after unbind.
242 */
243
244 /* too wordy: dev_printk(level , &(d)->gadget->dev , fmt , ## args) */
245 #define xprintk(d,level,fmt,args...) \
246 printk(level "%s: " fmt , shortname , ## args)
247
248 #ifdef DEBUG
249 #define DBG(dev,fmt,args...) \
250 xprintk(dev , KERN_DEBUG , fmt , ## args)
251 #else
252 #define DBG(dev,fmt,args...) \
253 do { } while (0)
254 #endif /* DEBUG */
255
256 #ifdef VERBOSE
257 #define VDEBUG DBG
258 #else
259 #define VDEBUG(dev,fmt,args...) \
260 do { } while (0)
261 #endif /* DEBUG */
262
263 #define ERROR(dev,fmt,args...) \
264 xprintk(dev , KERN_ERR , fmt , ## args)
265 #define WARN(dev,fmt,args...) \
266 xprintk(dev , KERN_WARNING , fmt , ## args)
267 #define INFO(dev,fmt,args...) \
268 xprintk(dev , KERN_INFO , fmt , ## args)
269
270
271 /*----------------------------------------------------------------------*/
272
273 /* SYNCHRONOUS ENDPOINT OPERATIONS (bulk/intr/iso)
274 *
275 * After opening, configure non-control endpoints. Then use normal
276 * stream read() and write() requests; and maybe ioctl() to get more
277 * precise FIFO status when recovering from cancellation.
278 */
279
280 static void epio_complete (struct usb_ep *ep, struct usb_request *req)
281 {
282 struct ep_data *epdata = ep->driver_data;
283
284 if (!req->context)
285 return;
286 if (req->status)
287 epdata->status = req->status;
288 else
289 epdata->status = req->actual;
290 complete ((struct completion *)req->context);
291 }
292
293 /* tasklock endpoint, returning when it's connected.
294 * still need dev->lock to use epdata->ep.
295 */
296 static int
297 get_ready_ep (unsigned f_flags, struct ep_data *epdata)
298 {
299 int val;
300
301 if (f_flags & O_NONBLOCK) {
302 if (down_trylock (&epdata->lock) != 0)
303 goto nonblock;
304 if (epdata->state != STATE_EP_ENABLED) {
305 up (&epdata->lock);
306 nonblock:
307 val = -EAGAIN;
308 } else
309 val = 0;
310 return val;
311 }
312
313 if ((val = down_interruptible (&epdata->lock)) < 0)
314 return val;
315
316 switch (epdata->state) {
317 case STATE_EP_ENABLED:
318 break;
319 // case STATE_EP_DISABLED: /* "can't happen" */
320 // case STATE_EP_READY: /* "can't happen" */
321 default: /* error! */
322 pr_debug ("%s: ep %p not available, state %d\n",
323 shortname, epdata, epdata->state);
324 // FALLTHROUGH
325 case STATE_EP_UNBOUND: /* clean disconnect */
326 val = -ENODEV;
327 up (&epdata->lock);
328 }
329 return val;
330 }
331
332 static ssize_t
333 ep_io (struct ep_data *epdata, void *buf, unsigned len)
334 {
335 DECLARE_COMPLETION_ONSTACK (done);
336 int value;
337
338 spin_lock_irq (&epdata->dev->lock);
339 if (likely (epdata->ep != NULL)) {
340 struct usb_request *req = epdata->req;
341
342 req->context = &done;
343 req->complete = epio_complete;
344 req->buf = buf;
345 req->length = len;
346 value = usb_ep_queue (epdata->ep, req, GFP_ATOMIC);
347 } else
348 value = -ENODEV;
349 spin_unlock_irq (&epdata->dev->lock);
350
351 if (likely (value == 0)) {
352 value = wait_event_interruptible (done.wait, done.done);
353 if (value != 0) {
354 spin_lock_irq (&epdata->dev->lock);
355 if (likely (epdata->ep != NULL)) {
356 DBG (epdata->dev, "%s i/o interrupted\n",
357 epdata->name);
358 usb_ep_dequeue (epdata->ep, epdata->req);
359 spin_unlock_irq (&epdata->dev->lock);
360
361 wait_event (done.wait, done.done);
362 if (epdata->status == -ECONNRESET)
363 epdata->status = -EINTR;
364 } else {
365 spin_unlock_irq (&epdata->dev->lock);
366
367 DBG (epdata->dev, "endpoint gone\n");
368 epdata->status = -ENODEV;
369 }
370 }
371 return epdata->status;
372 }
373 return value;
374 }
375
376
377 /* handle a synchronous OUT bulk/intr/iso transfer */
378 static ssize_t
379 ep_read (struct file *fd, char __user *buf, size_t len, loff_t *ptr)
380 {
381 struct ep_data *data = fd->private_data;
382 void *kbuf;
383 ssize_t value;
384
385 if ((value = get_ready_ep (fd->f_flags, data)) < 0)
386 return value;
387
388 /* halt any endpoint by doing a "wrong direction" i/o call */
389 if (data->desc.bEndpointAddress & USB_DIR_IN) {
390 if ((data->desc.bmAttributes & USB_ENDPOINT_XFERTYPE_MASK)
391 == USB_ENDPOINT_XFER_ISOC)
392 return -EINVAL;
393 DBG (data->dev, "%s halt\n", data->name);
394 spin_lock_irq (&data->dev->lock);
395 if (likely (data->ep != NULL))
396 usb_ep_set_halt (data->ep);
397 spin_unlock_irq (&data->dev->lock);
398 up (&data->lock);
399 return -EBADMSG;
400 }
401
402 /* FIXME readahead for O_NONBLOCK and poll(); careful with ZLPs */
403
404 value = -ENOMEM;
405 kbuf = kmalloc (len, GFP_KERNEL);
406 if (unlikely (!kbuf))
407 goto free1;
408
409 value = ep_io (data, kbuf, len);
410 VDEBUG (data->dev, "%s read %zu OUT, status %d\n",
411 data->name, len, (int) value);
412 if (value >= 0 && copy_to_user (buf, kbuf, value))
413 value = -EFAULT;
414
415 free1:
416 up (&data->lock);
417 kfree (kbuf);
418 return value;
419 }
420
421 /* handle a synchronous IN bulk/intr/iso transfer */
422 static ssize_t
423 ep_write (struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
424 {
425 struct ep_data *data = fd->private_data;
426 void *kbuf;
427 ssize_t value;
428
429 if ((value = get_ready_ep (fd->f_flags, data)) < 0)
430 return value;
431
432 /* halt any endpoint by doing a "wrong direction" i/o call */
433 if (!(data->desc.bEndpointAddress & USB_DIR_IN)) {
434 if ((data->desc.bmAttributes & USB_ENDPOINT_XFERTYPE_MASK)
435 == USB_ENDPOINT_XFER_ISOC)
436 return -EINVAL;
437 DBG (data->dev, "%s halt\n", data->name);
438 spin_lock_irq (&data->dev->lock);
439 if (likely (data->ep != NULL))
440 usb_ep_set_halt (data->ep);
441 spin_unlock_irq (&data->dev->lock);
442 up (&data->lock);
443 return -EBADMSG;
444 }
445
446 /* FIXME writebehind for O_NONBLOCK and poll(), qlen = 1 */
447
448 value = -ENOMEM;
449 kbuf = kmalloc (len, GFP_KERNEL);
450 if (!kbuf)
451 goto free1;
452 if (copy_from_user (kbuf, buf, len)) {
453 value = -EFAULT;
454 goto free1;
455 }
456
457 value = ep_io (data, kbuf, len);
458 VDEBUG (data->dev, "%s write %zu IN, status %d\n",
459 data->name, len, (int) value);
460 free1:
461 up (&data->lock);
462 kfree (kbuf);
463 return value;
464 }
465
466 static int
467 ep_release (struct inode *inode, struct file *fd)
468 {
469 struct ep_data *data = fd->private_data;
470 int value;
471
472 if ((value = down_interruptible(&data->lock)) < 0)
473 return value;
474
475 /* clean up if this can be reopened */
476 if (data->state != STATE_EP_UNBOUND) {
477 data->state = STATE_EP_DISABLED;
478 data->desc.bDescriptorType = 0;
479 data->hs_desc.bDescriptorType = 0;
480 usb_ep_disable(data->ep);
481 }
482 up (&data->lock);
483 put_ep (data);
484 return 0;
485 }
486
487 static int ep_ioctl (struct inode *inode, struct file *fd,
488 unsigned code, unsigned long value)
489 {
490 struct ep_data *data = fd->private_data;
491 int status;
492
493 if ((status = get_ready_ep (fd->f_flags, data)) < 0)
494 return status;
495
496 spin_lock_irq (&data->dev->lock);
497 if (likely (data->ep != NULL)) {
498 switch (code) {
499 case GADGETFS_FIFO_STATUS:
500 status = usb_ep_fifo_status (data->ep);
501 break;
502 case GADGETFS_FIFO_FLUSH:
503 usb_ep_fifo_flush (data->ep);
504 break;
505 case GADGETFS_CLEAR_HALT:
506 status = usb_ep_clear_halt (data->ep);
507 break;
508 default:
509 status = -ENOTTY;
510 }
511 } else
512 status = -ENODEV;
513 spin_unlock_irq (&data->dev->lock);
514 up (&data->lock);
515 return status;
516 }
517
518 /*----------------------------------------------------------------------*/
519
520 /* ASYNCHRONOUS ENDPOINT I/O OPERATIONS (bulk/intr/iso) */
521
522 struct kiocb_priv {
523 struct usb_request *req;
524 struct ep_data *epdata;
525 void *buf;
526 const struct iovec *iv;
527 unsigned long nr_segs;
528 unsigned actual;
529 };
530
531 static int ep_aio_cancel(struct kiocb *iocb, struct io_event *e)
532 {
533 struct kiocb_priv *priv = iocb->private;
534 struct ep_data *epdata;
535 int value;
536
537 local_irq_disable();
538 epdata = priv->epdata;
539 // spin_lock(&epdata->dev->lock);
540 kiocbSetCancelled(iocb);
541 if (likely(epdata && epdata->ep && priv->req))
542 value = usb_ep_dequeue (epdata->ep, priv->req);
543 else
544 value = -EINVAL;
545 // spin_unlock(&epdata->dev->lock);
546 local_irq_enable();
547
548 aio_put_req(iocb);
549 return value;
550 }
551
552 static ssize_t ep_aio_read_retry(struct kiocb *iocb)
553 {
554 struct kiocb_priv *priv = iocb->private;
555 ssize_t len, total;
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 for (i=0; i < priv->nr_segs; i++) {
564 ssize_t this = min((ssize_t)(priv->iv[i].iov_len), total);
565
566 if (copy_to_user(priv->iv[i].iov_base, priv->buf, this)) {
567 if (len == 0)
568 len = -EFAULT;
569 break;
570 }
571
572 total -= this;
573 len += this;
574 if (total == 0)
575 break;
576 }
577 kfree(priv->buf);
578 kfree(priv);
579 aio_put_req(iocb);
580 return len;
581 }
582
583 static void ep_aio_complete(struct usb_ep *ep, struct usb_request *req)
584 {
585 struct kiocb *iocb = req->context;
586 struct kiocb_priv *priv = iocb->private;
587 struct ep_data *epdata = priv->epdata;
588
589 /* lock against disconnect (and ideally, cancel) */
590 spin_lock(&epdata->dev->lock);
591 priv->req = NULL;
592 priv->epdata = NULL;
593 if (priv->iv == NULL
594 || unlikely(req->actual == 0)
595 || unlikely(kiocbIsCancelled(iocb))) {
596 kfree(req->buf);
597 kfree(priv);
598 iocb->private = NULL;
599 /* aio_complete() reports bytes-transferred _and_ faults */
600 if (unlikely(kiocbIsCancelled(iocb)))
601 aio_put_req(iocb);
602 else
603 aio_complete(iocb,
604 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 usb_ep_free_buffer (ep, req->buf, req->dma, req->length);
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 int free = 1;
937
938 /* for control OUT, data must still get to userspace */
939 if (!dev->setup_in) {
940 dev->setup_out_error = (req->status != 0);
941 if (!dev->setup_out_error)
942 free = 0;
943 dev->setup_out_ready = 1;
944 ep0_readable (dev);
945 } else if (dev->state == STATE_SETUP)
946 dev->state = STATE_CONNECTED;
947
948 /* clean up as appropriate */
949 if (free && req->buf != &dev->rbuf)
950 clean_req (ep, req);
951 req->complete = epio_complete;
952 }
953
954 static int setup_req (struct usb_ep *ep, struct usb_request *req, u16 len)
955 {
956 struct dev_data *dev = ep->driver_data;
957
958 if (dev->setup_out_ready) {
959 DBG (dev, "ep0 request busy!\n");
960 return -EBUSY;
961 }
962 if (len > sizeof (dev->rbuf))
963 req->buf = usb_ep_alloc_buffer (ep, len, &req->dma, GFP_ATOMIC);
964 if (req->buf == 0) {
965 req->buf = dev->rbuf;
966 return -ENOMEM;
967 }
968 req->complete = ep0_complete;
969 req->length = len;
970 req->zero = 0;
971 return 0;
972 }
973
974 static ssize_t
975 ep0_read (struct file *fd, char __user *buf, size_t len, loff_t *ptr)
976 {
977 struct dev_data *dev = fd->private_data;
978 ssize_t retval;
979 enum ep0_state state;
980
981 spin_lock_irq (&dev->lock);
982
983 /* report fd mode change before acting on it */
984 if (dev->setup_abort) {
985 dev->setup_abort = 0;
986 retval = -EIDRM;
987 goto done;
988 }
989
990 /* control DATA stage */
991 if ((state = dev->state) == STATE_SETUP) {
992
993 if (dev->setup_in) { /* stall IN */
994 VDEBUG(dev, "ep0in stall\n");
995 (void) usb_ep_set_halt (dev->gadget->ep0);
996 retval = -EL2HLT;
997 dev->state = STATE_CONNECTED;
998
999 } else if (len == 0) { /* ack SET_CONFIGURATION etc */
1000 struct usb_ep *ep = dev->gadget->ep0;
1001 struct usb_request *req = dev->req;
1002
1003 if ((retval = setup_req (ep, req, 0)) == 0)
1004 retval = usb_ep_queue (ep, req, GFP_ATOMIC);
1005 dev->state = STATE_CONNECTED;
1006
1007 /* assume that was SET_CONFIGURATION */
1008 if (dev->current_config) {
1009 unsigned power;
1010 #ifdef CONFIG_USB_GADGET_DUALSPEED
1011 if (dev->gadget->speed == USB_SPEED_HIGH)
1012 power = dev->hs_config->bMaxPower;
1013 else
1014 #endif
1015 power = dev->config->bMaxPower;
1016 usb_gadget_vbus_draw(dev->gadget, 2 * power);
1017 }
1018
1019 } else { /* collect OUT data */
1020 if ((fd->f_flags & O_NONBLOCK) != 0
1021 && !dev->setup_out_ready) {
1022 retval = -EAGAIN;
1023 goto done;
1024 }
1025 spin_unlock_irq (&dev->lock);
1026 retval = wait_event_interruptible (dev->wait,
1027 dev->setup_out_ready != 0);
1028
1029 /* FIXME state could change from under us */
1030 spin_lock_irq (&dev->lock);
1031 if (retval)
1032 goto done;
1033 if (dev->setup_out_error)
1034 retval = -EIO;
1035 else {
1036 len = min (len, (size_t)dev->req->actual);
1037 // FIXME don't call this with the spinlock held ...
1038 if (copy_to_user (buf, dev->req->buf, len))
1039 retval = -EFAULT;
1040 clean_req (dev->gadget->ep0, dev->req);
1041 /* NOTE userspace can't yet choose to stall */
1042 }
1043 }
1044 goto done;
1045 }
1046
1047 /* else normal: return event data */
1048 if (len < sizeof dev->event [0]) {
1049 retval = -EINVAL;
1050 goto done;
1051 }
1052 len -= len % sizeof (struct usb_gadgetfs_event);
1053 dev->usermode_setup = 1;
1054
1055 scan:
1056 /* return queued events right away */
1057 if (dev->ev_next != 0) {
1058 unsigned i, n;
1059 int tmp = dev->ev_next;
1060
1061 len = min (len, tmp * sizeof (struct usb_gadgetfs_event));
1062 n = len / sizeof (struct usb_gadgetfs_event);
1063
1064 /* ep0 can't deliver events when STATE_SETUP */
1065 for (i = 0; i < n; i++) {
1066 if (dev->event [i].type == GADGETFS_SETUP) {
1067 len = i + 1;
1068 len *= sizeof (struct usb_gadgetfs_event);
1069 n = 0;
1070 break;
1071 }
1072 }
1073 spin_unlock_irq (&dev->lock);
1074 if (copy_to_user (buf, &dev->event, len))
1075 retval = -EFAULT;
1076 else
1077 retval = len;
1078 if (len > 0) {
1079 len /= sizeof (struct usb_gadgetfs_event);
1080
1081 /* NOTE this doesn't guard against broken drivers;
1082 * concurrent ep0 readers may lose events.
1083 */
1084 spin_lock_irq (&dev->lock);
1085 dev->ev_next -= len;
1086 if (dev->ev_next != 0)
1087 memmove (&dev->event, &dev->event [len],
1088 sizeof (struct usb_gadgetfs_event)
1089 * (tmp - len));
1090 if (n == 0)
1091 dev->state = STATE_SETUP;
1092 spin_unlock_irq (&dev->lock);
1093 }
1094 return retval;
1095 }
1096 if (fd->f_flags & O_NONBLOCK) {
1097 retval = -EAGAIN;
1098 goto done;
1099 }
1100
1101 switch (state) {
1102 default:
1103 DBG (dev, "fail %s, state %d\n", __FUNCTION__, state);
1104 retval = -ESRCH;
1105 break;
1106 case STATE_UNCONNECTED:
1107 case STATE_CONNECTED:
1108 spin_unlock_irq (&dev->lock);
1109 DBG (dev, "%s wait\n", __FUNCTION__);
1110
1111 /* wait for events */
1112 retval = wait_event_interruptible (dev->wait,
1113 dev->ev_next != 0);
1114 if (retval < 0)
1115 return retval;
1116 spin_lock_irq (&dev->lock);
1117 goto scan;
1118 }
1119
1120 done:
1121 spin_unlock_irq (&dev->lock);
1122 return retval;
1123 }
1124
1125 static struct usb_gadgetfs_event *
1126 next_event (struct dev_data *dev, enum usb_gadgetfs_event_type type)
1127 {
1128 struct usb_gadgetfs_event *event;
1129 unsigned i;
1130
1131 switch (type) {
1132 /* these events purge the queue */
1133 case GADGETFS_DISCONNECT:
1134 if (dev->state == STATE_SETUP)
1135 dev->setup_abort = 1;
1136 // FALL THROUGH
1137 case GADGETFS_CONNECT:
1138 dev->ev_next = 0;
1139 break;
1140 case GADGETFS_SETUP: /* previous request timed out */
1141 case GADGETFS_SUSPEND: /* same effect */
1142 /* these events can't be repeated */
1143 for (i = 0; i != dev->ev_next; i++) {
1144 if (dev->event [i].type != type)
1145 continue;
1146 DBG (dev, "discard old event %d\n", type);
1147 dev->ev_next--;
1148 if (i == dev->ev_next)
1149 break;
1150 /* indices start at zero, for simplicity */
1151 memmove (&dev->event [i], &dev->event [i + 1],
1152 sizeof (struct usb_gadgetfs_event)
1153 * (dev->ev_next - i));
1154 }
1155 break;
1156 default:
1157 BUG ();
1158 }
1159 event = &dev->event [dev->ev_next++];
1160 BUG_ON (dev->ev_next > N_EVENT);
1161 VDEBUG (dev, "ev %d, next %d\n", type, dev->ev_next);
1162 memset (event, 0, sizeof *event);
1163 event->type = type;
1164 return event;
1165 }
1166
1167 static ssize_t
1168 ep0_write (struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
1169 {
1170 struct dev_data *dev = fd->private_data;
1171 ssize_t retval = -ESRCH;
1172
1173 spin_lock_irq (&dev->lock);
1174
1175 /* report fd mode change before acting on it */
1176 if (dev->setup_abort) {
1177 dev->setup_abort = 0;
1178 retval = -EIDRM;
1179
1180 /* data and/or status stage for control request */
1181 } else if (dev->state == STATE_SETUP) {
1182
1183 /* IN DATA+STATUS caller makes len <= wLength */
1184 if (dev->setup_in) {
1185 retval = setup_req (dev->gadget->ep0, dev->req, len);
1186 if (retval == 0) {
1187 spin_unlock_irq (&dev->lock);
1188 if (copy_from_user (dev->req->buf, buf, len))
1189 retval = -EFAULT;
1190 else {
1191 if (len < dev->setup_wLength)
1192 dev->req->zero = 1;
1193 retval = usb_ep_queue (
1194 dev->gadget->ep0, dev->req,
1195 GFP_KERNEL);
1196 }
1197 if (retval < 0) {
1198 spin_lock_irq (&dev->lock);
1199 clean_req (dev->gadget->ep0, dev->req);
1200 spin_unlock_irq (&dev->lock);
1201 } else
1202 retval = len;
1203
1204 return retval;
1205 }
1206
1207 /* can stall some OUT transfers */
1208 } else if (dev->setup_can_stall) {
1209 VDEBUG(dev, "ep0out stall\n");
1210 (void) usb_ep_set_halt (dev->gadget->ep0);
1211 retval = -EL2HLT;
1212 dev->state = STATE_CONNECTED;
1213 } else {
1214 DBG(dev, "bogus ep0out stall!\n");
1215 }
1216 } else
1217 DBG (dev, "fail %s, state %d\n", __FUNCTION__, dev->state);
1218
1219 spin_unlock_irq (&dev->lock);
1220 return retval;
1221 }
1222
1223 static int
1224 ep0_fasync (int f, struct file *fd, int on)
1225 {
1226 struct dev_data *dev = fd->private_data;
1227 // caller must F_SETOWN before signal delivery happens
1228 VDEBUG (dev, "%s %s\n", __FUNCTION__, on ? "on" : "off");
1229 return fasync_helper (f, fd, on, &dev->fasync);
1230 }
1231
1232 static struct usb_gadget_driver gadgetfs_driver;
1233
1234 static int
1235 dev_release (struct inode *inode, struct file *fd)
1236 {
1237 struct dev_data *dev = fd->private_data;
1238
1239 /* closing ep0 === shutdown all */
1240
1241 usb_gadget_unregister_driver (&gadgetfs_driver);
1242
1243 /* at this point "good" hardware has disconnected the
1244 * device from USB; the host won't see it any more.
1245 * alternatively, all host requests will time out.
1246 */
1247
1248 fasync_helper (-1, fd, 0, &dev->fasync);
1249 kfree (dev->buf);
1250 dev->buf = NULL;
1251 put_dev (dev);
1252
1253 /* other endpoints were all decoupled from this device */
1254 dev->state = STATE_DEV_DISABLED;
1255 return 0;
1256 }
1257
1258 static unsigned int
1259 ep0_poll (struct file *fd, poll_table *wait)
1260 {
1261 struct dev_data *dev = fd->private_data;
1262 int mask = 0;
1263
1264 poll_wait(fd, &dev->wait, wait);
1265
1266 spin_lock_irq (&dev->lock);
1267
1268 /* report fd mode change before acting on it */
1269 if (dev->setup_abort) {
1270 dev->setup_abort = 0;
1271 mask = POLLHUP;
1272 goto out;
1273 }
1274
1275 if (dev->state == STATE_SETUP) {
1276 if (dev->setup_in || dev->setup_can_stall)
1277 mask = POLLOUT;
1278 } else {
1279 if (dev->ev_next != 0)
1280 mask = POLLIN;
1281 }
1282 out:
1283 spin_unlock_irq(&dev->lock);
1284 return mask;
1285 }
1286
1287 static int dev_ioctl (struct inode *inode, struct file *fd,
1288 unsigned code, unsigned long value)
1289 {
1290 struct dev_data *dev = fd->private_data;
1291 struct usb_gadget *gadget = dev->gadget;
1292
1293 if (gadget->ops->ioctl)
1294 return gadget->ops->ioctl (gadget, code, value);
1295 return -ENOTTY;
1296 }
1297
1298 /* used after device configuration */
1299 static const struct file_operations ep0_io_operations = {
1300 .owner = THIS_MODULE,
1301 .llseek = no_llseek,
1302
1303 .read = ep0_read,
1304 .write = ep0_write,
1305 .fasync = ep0_fasync,
1306 .poll = ep0_poll,
1307 .ioctl = dev_ioctl,
1308 .release = dev_release,
1309 };
1310
1311 /*----------------------------------------------------------------------*/
1312
1313 /* The in-kernel gadget driver handles most ep0 issues, in particular
1314 * enumerating the single configuration (as provided from user space).
1315 *
1316 * Unrecognized ep0 requests may be handled in user space.
1317 */
1318
1319 #ifdef CONFIG_USB_GADGET_DUALSPEED
1320 static void make_qualifier (struct dev_data *dev)
1321 {
1322 struct usb_qualifier_descriptor qual;
1323 struct usb_device_descriptor *desc;
1324
1325 qual.bLength = sizeof qual;
1326 qual.bDescriptorType = USB_DT_DEVICE_QUALIFIER;
1327 qual.bcdUSB = __constant_cpu_to_le16 (0x0200);
1328
1329 desc = dev->dev;
1330 qual.bDeviceClass = desc->bDeviceClass;
1331 qual.bDeviceSubClass = desc->bDeviceSubClass;
1332 qual.bDeviceProtocol = desc->bDeviceProtocol;
1333
1334 /* assumes ep0 uses the same value for both speeds ... */
1335 qual.bMaxPacketSize0 = desc->bMaxPacketSize0;
1336
1337 qual.bNumConfigurations = 1;
1338 qual.bRESERVED = 0;
1339
1340 memcpy (dev->rbuf, &qual, sizeof qual);
1341 }
1342 #endif
1343
1344 static int
1345 config_buf (struct dev_data *dev, u8 type, unsigned index)
1346 {
1347 int len;
1348 #ifdef CONFIG_USB_GADGET_DUALSPEED
1349 int hs;
1350 #endif
1351
1352 /* only one configuration */
1353 if (index > 0)
1354 return -EINVAL;
1355
1356 #ifdef CONFIG_USB_GADGET_DUALSPEED
1357 hs = (dev->gadget->speed == USB_SPEED_HIGH);
1358 if (type == USB_DT_OTHER_SPEED_CONFIG)
1359 hs = !hs;
1360 if (hs) {
1361 dev->req->buf = dev->hs_config;
1362 len = le16_to_cpup (&dev->hs_config->wTotalLength);
1363 } else
1364 #endif
1365 {
1366 dev->req->buf = dev->config;
1367 len = le16_to_cpup (&dev->config->wTotalLength);
1368 }
1369 ((u8 *)dev->req->buf) [1] = type;
1370 return len;
1371 }
1372
1373 static int
1374 gadgetfs_setup (struct usb_gadget *gadget, const struct usb_ctrlrequest *ctrl)
1375 {
1376 struct dev_data *dev = get_gadget_data (gadget);
1377 struct usb_request *req = dev->req;
1378 int value = -EOPNOTSUPP;
1379 struct usb_gadgetfs_event *event;
1380 u16 w_value = le16_to_cpu(ctrl->wValue);
1381 u16 w_length = le16_to_cpu(ctrl->wLength);
1382
1383 spin_lock (&dev->lock);
1384 dev->setup_abort = 0;
1385 if (dev->state == STATE_UNCONNECTED) {
1386
1387 dev->state = STATE_CONNECTED;
1388 dev->dev->bMaxPacketSize0 = gadget->ep0->maxpacket;
1389
1390 #ifdef CONFIG_USB_GADGET_DUALSPEED
1391 if (gadget->speed == USB_SPEED_HIGH && dev->hs_config == 0) {
1392 ERROR (dev, "no high speed config??\n");
1393 return -EINVAL;
1394 }
1395 #endif /* CONFIG_USB_GADGET_DUALSPEED */
1396
1397 INFO (dev, "connected\n");
1398 event = next_event (dev, GADGETFS_CONNECT);
1399 event->u.speed = gadget->speed;
1400 ep0_readable (dev);
1401
1402 /* host may have given up waiting for response. we can miss control
1403 * requests handled lower down (device/endpoint status and features);
1404 * then ep0_{read,write} will report the wrong status. controller
1405 * driver will have aborted pending i/o.
1406 */
1407 } else if (dev->state == STATE_SETUP)
1408 dev->setup_abort = 1;
1409
1410 req->buf = dev->rbuf;
1411 req->dma = DMA_ADDR_INVALID;
1412 req->context = NULL;
1413 value = -EOPNOTSUPP;
1414 switch (ctrl->bRequest) {
1415
1416 case USB_REQ_GET_DESCRIPTOR:
1417 if (ctrl->bRequestType != USB_DIR_IN)
1418 goto unrecognized;
1419 switch (w_value >> 8) {
1420
1421 case USB_DT_DEVICE:
1422 value = min (w_length, (u16) sizeof *dev->dev);
1423 req->buf = dev->dev;
1424 break;
1425 #ifdef CONFIG_USB_GADGET_DUALSPEED
1426 case USB_DT_DEVICE_QUALIFIER:
1427 if (!dev->hs_config)
1428 break;
1429 value = min (w_length, (u16)
1430 sizeof (struct usb_qualifier_descriptor));
1431 make_qualifier (dev);
1432 break;
1433 case USB_DT_OTHER_SPEED_CONFIG:
1434 // FALLTHROUGH
1435 #endif
1436 case USB_DT_CONFIG:
1437 value = config_buf (dev,
1438 w_value >> 8,
1439 w_value & 0xff);
1440 if (value >= 0)
1441 value = min (w_length, (u16) value);
1442 break;
1443 case USB_DT_STRING:
1444 goto unrecognized;
1445
1446 default: // all others are errors
1447 break;
1448 }
1449 break;
1450
1451 /* currently one config, two speeds */
1452 case USB_REQ_SET_CONFIGURATION:
1453 if (ctrl->bRequestType != 0)
1454 break;
1455 if (0 == (u8) w_value) {
1456 value = 0;
1457 dev->current_config = 0;
1458 usb_gadget_vbus_draw(gadget, 8 /* mA */ );
1459 // user mode expected to disable endpoints
1460 } else {
1461 u8 config, power;
1462 #ifdef CONFIG_USB_GADGET_DUALSPEED
1463 if (gadget->speed == USB_SPEED_HIGH) {
1464 config = dev->hs_config->bConfigurationValue;
1465 power = dev->hs_config->bMaxPower;
1466 } else
1467 #endif
1468 {
1469 config = dev->config->bConfigurationValue;
1470 power = dev->config->bMaxPower;
1471 }
1472
1473 if (config == (u8) w_value) {
1474 value = 0;
1475 dev->current_config = config;
1476 usb_gadget_vbus_draw(gadget, 2 * power);
1477 }
1478 }
1479
1480 /* report SET_CONFIGURATION like any other control request,
1481 * except that usermode may not stall this. the next
1482 * request mustn't be allowed start until this finishes:
1483 * endpoints and threads set up, etc.
1484 *
1485 * NOTE: older PXA hardware (before PXA 255: without UDCCFR)
1486 * has bad/racey automagic that prevents synchronizing here.
1487 * even kernel mode drivers often miss them.
1488 */
1489 if (value == 0) {
1490 INFO (dev, "configuration #%d\n", dev->current_config);
1491 if (dev->usermode_setup) {
1492 dev->setup_can_stall = 0;
1493 goto delegate;
1494 }
1495 }
1496 break;
1497
1498 #ifndef CONFIG_USB_GADGETFS_PXA2XX
1499 /* PXA automagically handles this request too */
1500 case USB_REQ_GET_CONFIGURATION:
1501 if (ctrl->bRequestType != 0x80)
1502 break;
1503 *(u8 *)req->buf = dev->current_config;
1504 value = min (w_length, (u16) 1);
1505 break;
1506 #endif
1507
1508 default:
1509 unrecognized:
1510 VDEBUG (dev, "%s req%02x.%02x v%04x i%04x l%d\n",
1511 dev->usermode_setup ? "delegate" : "fail",
1512 ctrl->bRequestType, ctrl->bRequest,
1513 w_value, le16_to_cpu(ctrl->wIndex), w_length);
1514
1515 /* if there's an ep0 reader, don't stall */
1516 if (dev->usermode_setup) {
1517 dev->setup_can_stall = 1;
1518 delegate:
1519 dev->setup_in = (ctrl->bRequestType & USB_DIR_IN)
1520 ? 1 : 0;
1521 dev->setup_wLength = w_length;
1522 dev->setup_out_ready = 0;
1523 dev->setup_out_error = 0;
1524 value = 0;
1525
1526 /* read DATA stage for OUT right away */
1527 if (unlikely (!dev->setup_in && w_length)) {
1528 value = setup_req (gadget->ep0, dev->req,
1529 w_length);
1530 if (value < 0)
1531 break;
1532 value = usb_ep_queue (gadget->ep0, dev->req,
1533 GFP_ATOMIC);
1534 if (value < 0) {
1535 clean_req (gadget->ep0, dev->req);
1536 break;
1537 }
1538
1539 /* we can't currently stall these */
1540 dev->setup_can_stall = 0;
1541 }
1542
1543 /* state changes when reader collects event */
1544 event = next_event (dev, GADGETFS_SETUP);
1545 event->u.setup = *ctrl;
1546 ep0_readable (dev);
1547 spin_unlock (&dev->lock);
1548 return 0;
1549 }
1550 }
1551
1552 /* proceed with data transfer and status phases? */
1553 if (value >= 0 && dev->state != STATE_SETUP) {
1554 req->length = value;
1555 req->zero = value < w_length;
1556 value = usb_ep_queue (gadget->ep0, req, GFP_ATOMIC);
1557 if (value < 0) {
1558 DBG (dev, "ep_queue --> %d\n", value);
1559 req->status = 0;
1560 }
1561 }
1562
1563 /* device stalls when value < 0 */
1564 spin_unlock (&dev->lock);
1565 return value;
1566 }
1567
1568 static void destroy_ep_files (struct dev_data *dev)
1569 {
1570 struct list_head *entry, *tmp;
1571
1572 DBG (dev, "%s %d\n", __FUNCTION__, dev->state);
1573
1574 /* dev->state must prevent interference */
1575 restart:
1576 spin_lock_irq (&dev->lock);
1577 list_for_each_safe (entry, tmp, &dev->epfiles) {
1578 struct ep_data *ep;
1579 struct inode *parent;
1580 struct dentry *dentry;
1581
1582 /* break link to FS */
1583 ep = list_entry (entry, struct ep_data, epfiles);
1584 list_del_init (&ep->epfiles);
1585 dentry = ep->dentry;
1586 ep->dentry = NULL;
1587 parent = dentry->d_parent->d_inode;
1588
1589 /* break link to controller */
1590 if (ep->state == STATE_EP_ENABLED)
1591 (void) usb_ep_disable (ep->ep);
1592 ep->state = STATE_EP_UNBOUND;
1593 usb_ep_free_request (ep->ep, ep->req);
1594 ep->ep = NULL;
1595 wake_up (&ep->wait);
1596 put_ep (ep);
1597
1598 spin_unlock_irq (&dev->lock);
1599
1600 /* break link to dcache */
1601 mutex_lock (&parent->i_mutex);
1602 d_delete (dentry);
1603 dput (dentry);
1604 mutex_unlock (&parent->i_mutex);
1605
1606 /* fds may still be open */
1607 goto restart;
1608 }
1609 spin_unlock_irq (&dev->lock);
1610 }
1611
1612
1613 static struct inode *
1614 gadgetfs_create_file (struct super_block *sb, char const *name,
1615 void *data, const struct file_operations *fops,
1616 struct dentry **dentry_p);
1617
1618 static int activate_ep_files (struct dev_data *dev)
1619 {
1620 struct usb_ep *ep;
1621 struct ep_data *data;
1622
1623 gadget_for_each_ep (ep, dev->gadget) {
1624
1625 data = kzalloc(sizeof(*data), GFP_KERNEL);
1626 if (!data)
1627 goto enomem0;
1628 data->state = STATE_EP_DISABLED;
1629 init_MUTEX (&data->lock);
1630 init_waitqueue_head (&data->wait);
1631
1632 strncpy (data->name, ep->name, sizeof (data->name) - 1);
1633 atomic_set (&data->count, 1);
1634 data->dev = dev;
1635 get_dev (dev);
1636
1637 data->ep = ep;
1638 ep->driver_data = data;
1639
1640 data->req = usb_ep_alloc_request (ep, GFP_KERNEL);
1641 if (!data->req)
1642 goto enomem1;
1643
1644 data->inode = gadgetfs_create_file (dev->sb, data->name,
1645 data, &ep_config_operations,
1646 &data->dentry);
1647 if (!data->inode)
1648 goto enomem2;
1649 list_add_tail (&data->epfiles, &dev->epfiles);
1650 }
1651 return 0;
1652
1653 enomem2:
1654 usb_ep_free_request (ep, data->req);
1655 enomem1:
1656 put_dev (dev);
1657 kfree (data);
1658 enomem0:
1659 DBG (dev, "%s enomem\n", __FUNCTION__);
1660 destroy_ep_files (dev);
1661 return -ENOMEM;
1662 }
1663
1664 static void
1665 gadgetfs_unbind (struct usb_gadget *gadget)
1666 {
1667 struct dev_data *dev = get_gadget_data (gadget);
1668
1669 DBG (dev, "%s\n", __FUNCTION__);
1670
1671 spin_lock_irq (&dev->lock);
1672 dev->state = STATE_DEV_UNBOUND;
1673 spin_unlock_irq (&dev->lock);
1674
1675 destroy_ep_files (dev);
1676 gadget->ep0->driver_data = NULL;
1677 set_gadget_data (gadget, NULL);
1678
1679 /* we've already been disconnected ... no i/o is active */
1680 if (dev->req)
1681 usb_ep_free_request (gadget->ep0, dev->req);
1682 DBG (dev, "%s done\n", __FUNCTION__);
1683 put_dev (dev);
1684 }
1685
1686 static struct dev_data *the_device;
1687
1688 static int
1689 gadgetfs_bind (struct usb_gadget *gadget)
1690 {
1691 struct dev_data *dev = the_device;
1692
1693 if (!dev)
1694 return -ESRCH;
1695 if (0 != strcmp (CHIP, gadget->name)) {
1696 printk (KERN_ERR "%s expected %s controller not %s\n",
1697 shortname, CHIP, gadget->name);
1698 return -ENODEV;
1699 }
1700
1701 set_gadget_data (gadget, dev);
1702 dev->gadget = gadget;
1703 gadget->ep0->driver_data = dev;
1704 dev->dev->bMaxPacketSize0 = gadget->ep0->maxpacket;
1705
1706 /* preallocate control response and buffer */
1707 dev->req = usb_ep_alloc_request (gadget->ep0, GFP_KERNEL);
1708 if (!dev->req)
1709 goto enomem;
1710 dev->req->context = NULL;
1711 dev->req->complete = epio_complete;
1712
1713 if (activate_ep_files (dev) < 0)
1714 goto enomem;
1715
1716 INFO (dev, "bound to %s driver\n", gadget->name);
1717 dev->state = STATE_UNCONNECTED;
1718 get_dev (dev);
1719 return 0;
1720
1721 enomem:
1722 gadgetfs_unbind (gadget);
1723 return -ENOMEM;
1724 }
1725
1726 static void
1727 gadgetfs_disconnect (struct usb_gadget *gadget)
1728 {
1729 struct dev_data *dev = get_gadget_data (gadget);
1730
1731 spin_lock (&dev->lock);
1732 if (dev->state == STATE_UNCONNECTED) {
1733 DBG (dev, "already unconnected\n");
1734 goto exit;
1735 }
1736 dev->state = STATE_UNCONNECTED;
1737
1738 INFO (dev, "disconnected\n");
1739 next_event (dev, GADGETFS_DISCONNECT);
1740 ep0_readable (dev);
1741 exit:
1742 spin_unlock (&dev->lock);
1743 }
1744
1745 static void
1746 gadgetfs_suspend (struct usb_gadget *gadget)
1747 {
1748 struct dev_data *dev = get_gadget_data (gadget);
1749
1750 INFO (dev, "suspended from state %d\n", dev->state);
1751 spin_lock (&dev->lock);
1752 switch (dev->state) {
1753 case STATE_SETUP: // VERY odd... host died??
1754 case STATE_CONNECTED:
1755 case STATE_UNCONNECTED:
1756 next_event (dev, GADGETFS_SUSPEND);
1757 ep0_readable (dev);
1758 /* FALLTHROUGH */
1759 default:
1760 break;
1761 }
1762 spin_unlock (&dev->lock);
1763 }
1764
1765 static struct usb_gadget_driver gadgetfs_driver = {
1766 #ifdef CONFIG_USB_GADGET_DUALSPEED
1767 .speed = USB_SPEED_HIGH,
1768 #else
1769 .speed = USB_SPEED_FULL,
1770 #endif
1771 .function = (char *) driver_desc,
1772 .bind = gadgetfs_bind,
1773 .unbind = gadgetfs_unbind,
1774 .setup = gadgetfs_setup,
1775 .disconnect = gadgetfs_disconnect,
1776 .suspend = gadgetfs_suspend,
1777
1778 .driver = {
1779 .name = (char *) shortname,
1780 },
1781 };
1782
1783 /*----------------------------------------------------------------------*/
1784
1785 static void gadgetfs_nop(struct usb_gadget *arg) { }
1786
1787 static int gadgetfs_probe (struct usb_gadget *gadget)
1788 {
1789 CHIP = gadget->name;
1790 return -EISNAM;
1791 }
1792
1793 static struct usb_gadget_driver probe_driver = {
1794 .speed = USB_SPEED_HIGH,
1795 .bind = gadgetfs_probe,
1796 .unbind = gadgetfs_nop,
1797 .setup = (void *)gadgetfs_nop,
1798 .disconnect = gadgetfs_nop,
1799 .driver = {
1800 .name = "nop",
1801 },
1802 };
1803
1804
1805 /* DEVICE INITIALIZATION
1806 *
1807 * fd = open ("/dev/gadget/$CHIP", O_RDWR)
1808 * status = write (fd, descriptors, sizeof descriptors)
1809 *
1810 * That write establishes the device configuration, so the kernel can
1811 * bind to the controller ... guaranteeing it can handle enumeration
1812 * at all necessary speeds. Descriptor order is:
1813 *
1814 * . message tag (u32, host order) ... for now, must be zero; it
1815 * would change to support features like multi-config devices
1816 * . full/low speed config ... all wTotalLength bytes (with interface,
1817 * class, altsetting, endpoint, and other descriptors)
1818 * . high speed config ... all descriptors, for high speed operation;
1819 * this one's optional except for high-speed hardware
1820 * . device descriptor
1821 *
1822 * Endpoints are not yet enabled. Drivers must wait until device
1823 * configuration and interface altsetting changes create
1824 * the need to configure (or unconfigure) them.
1825 *
1826 * After initialization, the device stays active for as long as that
1827 * $CHIP file is open. Events must then be read from that descriptor,
1828 * such as configuration notifications.
1829 */
1830
1831 static int is_valid_config (struct usb_config_descriptor *config)
1832 {
1833 return config->bDescriptorType == USB_DT_CONFIG
1834 && config->bLength == USB_DT_CONFIG_SIZE
1835 && config->bConfigurationValue != 0
1836 && (config->bmAttributes & USB_CONFIG_ATT_ONE) != 0
1837 && (config->bmAttributes & USB_CONFIG_ATT_WAKEUP) == 0;
1838 /* FIXME if gadget->is_otg, _must_ include an otg descriptor */
1839 /* FIXME check lengths: walk to end */
1840 }
1841
1842 static ssize_t
1843 dev_config (struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
1844 {
1845 struct dev_data *dev = fd->private_data;
1846 ssize_t value = len, length = len;
1847 unsigned total;
1848 u32 tag;
1849 char *kbuf;
1850
1851 if (dev->state != STATE_OPENED)
1852 return -EEXIST;
1853
1854 if (len < (USB_DT_CONFIG_SIZE + USB_DT_DEVICE_SIZE + 4))
1855 return -EINVAL;
1856
1857 /* we might need to change message format someday */
1858 if (copy_from_user (&tag, buf, 4))
1859 return -EFAULT;
1860 if (tag != 0)
1861 return -EINVAL;
1862 buf += 4;
1863 length -= 4;
1864
1865 kbuf = kmalloc (length, GFP_KERNEL);
1866 if (!kbuf)
1867 return -ENOMEM;
1868 if (copy_from_user (kbuf, buf, length)) {
1869 kfree (kbuf);
1870 return -EFAULT;
1871 }
1872
1873 spin_lock_irq (&dev->lock);
1874 value = -EINVAL;
1875 if (dev->buf)
1876 goto fail;
1877 dev->buf = kbuf;
1878
1879 /* full or low speed config */
1880 dev->config = (void *) kbuf;
1881 total = le16_to_cpup (&dev->config->wTotalLength);
1882 if (!is_valid_config (dev->config) || total >= length)
1883 goto fail;
1884 kbuf += total;
1885 length -= total;
1886
1887 /* optional high speed config */
1888 if (kbuf [1] == USB_DT_CONFIG) {
1889 dev->hs_config = (void *) kbuf;
1890 total = le16_to_cpup (&dev->hs_config->wTotalLength);
1891 if (!is_valid_config (dev->hs_config) || total >= length)
1892 goto fail;
1893 kbuf += total;
1894 length -= total;
1895 }
1896
1897 /* could support multiple configs, using another encoding! */
1898
1899 /* device descriptor (tweaked for paranoia) */
1900 if (length != USB_DT_DEVICE_SIZE)
1901 goto fail;
1902 dev->dev = (void *)kbuf;
1903 if (dev->dev->bLength != USB_DT_DEVICE_SIZE
1904 || dev->dev->bDescriptorType != USB_DT_DEVICE
1905 || dev->dev->bNumConfigurations != 1)
1906 goto fail;
1907 dev->dev->bNumConfigurations = 1;
1908 dev->dev->bcdUSB = __constant_cpu_to_le16 (0x0200);
1909
1910 /* triggers gadgetfs_bind(); then we can enumerate. */
1911 spin_unlock_irq (&dev->lock);
1912 value = usb_gadget_register_driver (&gadgetfs_driver);
1913 if (value != 0) {
1914 kfree (dev->buf);
1915 dev->buf = NULL;
1916 } else {
1917 /* at this point "good" hardware has for the first time
1918 * let the USB the host see us. alternatively, if users
1919 * unplug/replug that will clear all the error state.
1920 *
1921 * note: everything running before here was guaranteed
1922 * to choke driver model style diagnostics. from here
1923 * on, they can work ... except in cleanup paths that
1924 * kick in after the ep0 descriptor is closed.
1925 */
1926 fd->f_op = &ep0_io_operations;
1927 value = len;
1928 }
1929 return value;
1930
1931 fail:
1932 spin_unlock_irq (&dev->lock);
1933 pr_debug ("%s: %s fail %Zd, %p\n", shortname, __FUNCTION__, value, dev);
1934 kfree (dev->buf);
1935 dev->buf = NULL;
1936 return value;
1937 }
1938
1939 static int
1940 dev_open (struct inode *inode, struct file *fd)
1941 {
1942 struct dev_data *dev = inode->i_private;
1943 int value = -EBUSY;
1944
1945 if (dev->state == STATE_DEV_DISABLED) {
1946 dev->ev_next = 0;
1947 dev->state = STATE_OPENED;
1948 fd->private_data = dev;
1949 get_dev (dev);
1950 value = 0;
1951 }
1952 return value;
1953 }
1954
1955 static const struct file_operations dev_init_operations = {
1956 .owner = THIS_MODULE,
1957 .llseek = no_llseek,
1958
1959 .open = dev_open,
1960 .write = dev_config,
1961 .fasync = ep0_fasync,
1962 .ioctl = dev_ioctl,
1963 .release = dev_release,
1964 };
1965
1966 /*----------------------------------------------------------------------*/
1967
1968 /* FILESYSTEM AND SUPERBLOCK OPERATIONS
1969 *
1970 * Mounting the filesystem creates a controller file, used first for
1971 * device configuration then later for event monitoring.
1972 */
1973
1974
1975 /* FIXME PAM etc could set this security policy without mount options
1976 * if epfiles inherited ownership and permissons from ep0 ...
1977 */
1978
1979 static unsigned default_uid;
1980 static unsigned default_gid;
1981 static unsigned default_perm = S_IRUSR | S_IWUSR;
1982
1983 module_param (default_uid, uint, 0644);
1984 module_param (default_gid, uint, 0644);
1985 module_param (default_perm, uint, 0644);
1986
1987
1988 static struct inode *
1989 gadgetfs_make_inode (struct super_block *sb,
1990 void *data, const struct file_operations *fops,
1991 int mode)
1992 {
1993 struct inode *inode = new_inode (sb);
1994
1995 if (inode) {
1996 inode->i_mode = mode;
1997 inode->i_uid = default_uid;
1998 inode->i_gid = default_gid;
1999 inode->i_blocks = 0;
2000 inode->i_atime = inode->i_mtime = inode->i_ctime
2001 = CURRENT_TIME;
2002 inode->i_private = data;
2003 inode->i_fop = fops;
2004 }
2005 return inode;
2006 }
2007
2008 /* creates in fs root directory, so non-renamable and non-linkable.
2009 * so inode and dentry are paired, until device reconfig.
2010 */
2011 static struct inode *
2012 gadgetfs_create_file (struct super_block *sb, char const *name,
2013 void *data, const struct file_operations *fops,
2014 struct dentry **dentry_p)
2015 {
2016 struct dentry *dentry;
2017 struct inode *inode;
2018
2019 dentry = d_alloc_name(sb->s_root, name);
2020 if (!dentry)
2021 return NULL;
2022
2023 inode = gadgetfs_make_inode (sb, data, fops,
2024 S_IFREG | (default_perm & S_IRWXUGO));
2025 if (!inode) {
2026 dput(dentry);
2027 return NULL;
2028 }
2029 d_add (dentry, inode);
2030 *dentry_p = dentry;
2031 return inode;
2032 }
2033
2034 static struct super_operations gadget_fs_operations = {
2035 .statfs = simple_statfs,
2036 .drop_inode = generic_delete_inode,
2037 };
2038
2039 static int
2040 gadgetfs_fill_super (struct super_block *sb, void *opts, int silent)
2041 {
2042 struct inode *inode;
2043 struct dentry *d;
2044 struct dev_data *dev;
2045
2046 if (the_device)
2047 return -ESRCH;
2048
2049 /* fake probe to determine $CHIP */
2050 (void) usb_gadget_register_driver (&probe_driver);
2051 if (!CHIP)
2052 return -ENODEV;
2053
2054 /* superblock */
2055 sb->s_blocksize = PAGE_CACHE_SIZE;
2056 sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
2057 sb->s_magic = GADGETFS_MAGIC;
2058 sb->s_op = &gadget_fs_operations;
2059 sb->s_time_gran = 1;
2060
2061 /* root inode */
2062 inode = gadgetfs_make_inode (sb,
2063 NULL, &simple_dir_operations,
2064 S_IFDIR | S_IRUGO | S_IXUGO);
2065 if (!inode)
2066 goto enomem0;
2067 inode->i_op = &simple_dir_inode_operations;
2068 if (!(d = d_alloc_root (inode)))
2069 goto enomem1;
2070 sb->s_root = d;
2071
2072 /* the ep0 file is named after the controller we expect;
2073 * user mode code can use it for sanity checks, like we do.
2074 */
2075 dev = dev_new ();
2076 if (!dev)
2077 goto enomem2;
2078
2079 dev->sb = sb;
2080 if (!gadgetfs_create_file (sb, CHIP,
2081 dev, &dev_init_operations,
2082 &dev->dentry))
2083 goto enomem3;
2084
2085 /* other endpoint files are available after hardware setup,
2086 * from binding to a controller.
2087 */
2088 the_device = dev;
2089 return 0;
2090
2091 enomem3:
2092 put_dev (dev);
2093 enomem2:
2094 dput (d);
2095 enomem1:
2096 iput (inode);
2097 enomem0:
2098 return -ENOMEM;
2099 }
2100
2101 /* "mount -t gadgetfs path /dev/gadget" ends up here */
2102 static int
2103 gadgetfs_get_sb (struct file_system_type *t, int flags,
2104 const char *path, void *opts, struct vfsmount *mnt)
2105 {
2106 return get_sb_single (t, flags, opts, gadgetfs_fill_super, mnt);
2107 }
2108
2109 static void
2110 gadgetfs_kill_sb (struct super_block *sb)
2111 {
2112 kill_litter_super (sb);
2113 if (the_device) {
2114 put_dev (the_device);
2115 the_device = NULL;
2116 }
2117 }
2118
2119 /*----------------------------------------------------------------------*/
2120
2121 static struct file_system_type gadgetfs_type = {
2122 .owner = THIS_MODULE,
2123 .name = shortname,
2124 .get_sb = gadgetfs_get_sb,
2125 .kill_sb = gadgetfs_kill_sb,
2126 };
2127
2128 /*----------------------------------------------------------------------*/
2129
2130 static int __init init (void)
2131 {
2132 int status;
2133
2134 status = register_filesystem (&gadgetfs_type);
2135 if (status == 0)
2136 pr_info ("%s: %s, version " DRIVER_VERSION "\n",
2137 shortname, driver_desc);
2138 return status;
2139 }
2140 module_init (init);
2141
2142 static void __exit cleanup (void)
2143 {
2144 pr_debug ("unregister %s\n", shortname);
2145 unregister_filesystem (&gadgetfs_type);
2146 }
2147 module_exit (cleanup);
2148
Linus' kernel tree