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USB: gadgetfs: use helper functions to determine endpoint type and direction
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / drivers / usb / gadget / inode.c
blob7d33f50b5874bc683ed42db17aa87c8b59544035
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 #include <linux/smp_lock.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_DEV_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_DEV_UNCONNECTED,
109 STATE_DEV_CONNECTED,
110 STATE_DEV_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; /* P: lock */
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_DEBUG
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 INFO(dev,fmt,args...) \
266 xprintk(dev , KERN_INFO , fmt , ## args)
267
268
269 /*----------------------------------------------------------------------*/
270
271 /* SYNCHRONOUS ENDPOINT OPERATIONS (bulk/intr/iso)
272 *
273 * After opening, configure non-control endpoints. Then use normal
274 * stream read() and write() requests; and maybe ioctl() to get more
275 * precise FIFO status when recovering from cancellation.
276 */
277
278 static void epio_complete (struct usb_ep *ep, struct usb_request *req)
279 {
280 struct ep_data *epdata = ep->driver_data;
281
282 if (!req->context)
283 return;
284 if (req->status)
285 epdata->status = req->status;
286 else
287 epdata->status = req->actual;
288 complete ((struct completion *)req->context);
289 }
290
291 /* tasklock endpoint, returning when it's connected.
292 * still need dev->lock to use epdata->ep.
293 */
294 static int
295 get_ready_ep (unsigned f_flags, struct ep_data *epdata)
296 {
297 int val;
298
299 if (f_flags & O_NONBLOCK) {
300 if (down_trylock (&epdata->lock) != 0)
301 goto nonblock;
302 if (epdata->state != STATE_EP_ENABLED) {
303 up (&epdata->lock);
304 nonblock:
305 val = -EAGAIN;
306 } else
307 val = 0;
308 return val;
309 }
310
311 if ((val = down_interruptible (&epdata->lock)) < 0)
312 return val;
313
314 switch (epdata->state) {
315 case STATE_EP_ENABLED:
316 break;
317 // case STATE_EP_DISABLED: /* "can't happen" */
318 // case STATE_EP_READY: /* "can't happen" */
319 default: /* error! */
320 pr_debug ("%s: ep %p not available, state %d\n",
321 shortname, epdata, epdata->state);
322 // FALLTHROUGH
323 case STATE_EP_UNBOUND: /* clean disconnect */
324 val = -ENODEV;
325 up (&epdata->lock);
326 }
327 return val;
328 }
329
330 static ssize_t
331 ep_io (struct ep_data *epdata, void *buf, unsigned len)
332 {
333 DECLARE_COMPLETION_ONSTACK (done);
334 int value;
335
336 spin_lock_irq (&epdata->dev->lock);
337 if (likely (epdata->ep != NULL)) {
338 struct usb_request *req = epdata->req;
339
340 req->context = &done;
341 req->complete = epio_complete;
342 req->buf = buf;
343 req->length = len;
344 value = usb_ep_queue (epdata->ep, req, GFP_ATOMIC);
345 } else
346 value = -ENODEV;
347 spin_unlock_irq (&epdata->dev->lock);
348
349 if (likely (value == 0)) {
350 value = wait_event_interruptible (done.wait, done.done);
351 if (value != 0) {
352 spin_lock_irq (&epdata->dev->lock);
353 if (likely (epdata->ep != NULL)) {
354 DBG (epdata->dev, "%s i/o interrupted\n",
355 epdata->name);
356 usb_ep_dequeue (epdata->ep, epdata->req);
357 spin_unlock_irq (&epdata->dev->lock);
358
359 wait_event (done.wait, done.done);
360 if (epdata->status == -ECONNRESET)
361 epdata->status = -EINTR;
362 } else {
363 spin_unlock_irq (&epdata->dev->lock);
364
365 DBG (epdata->dev, "endpoint gone\n");
366 epdata->status = -ENODEV;
367 }
368 }
369 return epdata->status;
370 }
371 return value;
372 }
373
374
375 /* handle a synchronous OUT bulk/intr/iso transfer */
376 static ssize_t
377 ep_read (struct file *fd, char __user *buf, size_t len, loff_t *ptr)
378 {
379 struct ep_data *data = fd->private_data;
380 void *kbuf;
381 ssize_t value;
382
383 if ((value = get_ready_ep (fd->f_flags, data)) < 0)
384 return value;
385
386 /* halt any endpoint by doing a "wrong direction" i/o call */
387 if (usb_endpoint_dir_in(&data->desc)) {
388 if (usb_endpoint_xfer_isoc(&data->desc))
389 return -EINVAL;
390 DBG (data->dev, "%s halt\n", data->name);
391 spin_lock_irq (&data->dev->lock);
392 if (likely (data->ep != NULL))
393 usb_ep_set_halt (data->ep);
394 spin_unlock_irq (&data->dev->lock);
395 up (&data->lock);
396 return -EBADMSG;
397 }
398
399 /* FIXME readahead for O_NONBLOCK and poll(); careful with ZLPs */
400
401 value = -ENOMEM;
402 kbuf = kmalloc (len, GFP_KERNEL);
403 if (unlikely (!kbuf))
404 goto free1;
405
406 value = ep_io (data, kbuf, len);
407 VDEBUG (data->dev, "%s read %zu OUT, status %d\n",
408 data->name, len, (int) value);
409 if (value >= 0 && copy_to_user (buf, kbuf, value))
410 value = -EFAULT;
411
412 free1:
413 up (&data->lock);
414 kfree (kbuf);
415 return value;
416 }
417
418 /* handle a synchronous IN bulk/intr/iso transfer */
419 static ssize_t
420 ep_write (struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
421 {
422 struct ep_data *data = fd->private_data;
423 void *kbuf;
424 ssize_t value;
425
426 if ((value = get_ready_ep (fd->f_flags, data)) < 0)
427 return value;
428
429 /* halt any endpoint by doing a "wrong direction" i/o call */
430 if (!usb_endpoint_dir_in(&data->desc)) {
431 if (usb_endpoint_xfer_isoc(&data->desc))
432 return -EINVAL;
433 DBG (data->dev, "%s halt\n", data->name);
434 spin_lock_irq (&data->dev->lock);
435 if (likely (data->ep != NULL))
436 usb_ep_set_halt (data->ep);
437 spin_unlock_irq (&data->dev->lock);
438 up (&data->lock);
439 return -EBADMSG;
440 }
441
442 /* FIXME writebehind for O_NONBLOCK and poll(), qlen = 1 */
443
444 value = -ENOMEM;
445 kbuf = kmalloc (len, GFP_KERNEL);
446 if (!kbuf)
447 goto free1;
448 if (copy_from_user (kbuf, buf, len)) {
449 value = -EFAULT;
450 goto free1;
451 }
452
453 value = ep_io (data, kbuf, len);
454 VDEBUG (data->dev, "%s write %zu IN, status %d\n",
455 data->name, len, (int) value);
456 free1:
457 up (&data->lock);
458 kfree (kbuf);
459 return value;
460 }
461
462 static int
463 ep_release (struct inode *inode, struct file *fd)
464 {
465 struct ep_data *data = fd->private_data;
466 int value;
467
468 if ((value = down_interruptible(&data->lock)) < 0)
469 return value;
470
471 /* clean up if this can be reopened */
472 if (data->state != STATE_EP_UNBOUND) {
473 data->state = STATE_EP_DISABLED;
474 data->desc.bDescriptorType = 0;
475 data->hs_desc.bDescriptorType = 0;
476 usb_ep_disable(data->ep);
477 }
478 up (&data->lock);
479 put_ep (data);
480 return 0;
481 }
482
483 static long ep_ioctl(struct file *fd, unsigned code, unsigned long value)
484 {
485 struct ep_data *data = fd->private_data;
486 int status;
487
488 if ((status = get_ready_ep (fd->f_flags, data)) < 0)
489 return status;
490
491 spin_lock_irq (&data->dev->lock);
492 if (likely (data->ep != NULL)) {
493 switch (code) {
494 case GADGETFS_FIFO_STATUS:
495 status = usb_ep_fifo_status (data->ep);
496 break;
497 case GADGETFS_FIFO_FLUSH:
498 usb_ep_fifo_flush (data->ep);
499 break;
500 case GADGETFS_CLEAR_HALT:
501 status = usb_ep_clear_halt (data->ep);
502 break;
503 default:
504 status = -ENOTTY;
505 }
506 } else
507 status = -ENODEV;
508 spin_unlock_irq (&data->dev->lock);
509 up (&data->lock);
510 return status;
511 }
512
513 /*----------------------------------------------------------------------*/
514
515 /* ASYNCHRONOUS ENDPOINT I/O OPERATIONS (bulk/intr/iso) */
516
517 struct kiocb_priv {
518 struct usb_request *req;
519 struct ep_data *epdata;
520 void *buf;
521 const struct iovec *iv;
522 unsigned long nr_segs;
523 unsigned actual;
524 };
525
526 static int ep_aio_cancel(struct kiocb *iocb, struct io_event *e)
527 {
528 struct kiocb_priv *priv = iocb->private;
529 struct ep_data *epdata;
530 int value;
531
532 local_irq_disable();
533 epdata = priv->epdata;
534 // spin_lock(&epdata->dev->lock);
535 kiocbSetCancelled(iocb);
536 if (likely(epdata && epdata->ep && priv->req))
537 value = usb_ep_dequeue (epdata->ep, priv->req);
538 else
539 value = -EINVAL;
540 // spin_unlock(&epdata->dev->lock);
541 local_irq_enable();
542
543 aio_put_req(iocb);
544 return value;
545 }
546
547 static ssize_t ep_aio_read_retry(struct kiocb *iocb)
548 {
549 struct kiocb_priv *priv = iocb->private;
550 ssize_t len, total;
551 void *to_copy;
552 int i;
553
554 /* we "retry" to get the right mm context for this: */
555
556 /* copy stuff into user buffers */
557 total = priv->actual;
558 len = 0;
559 to_copy = priv->buf;
560 for (i=0; i < priv->nr_segs; i++) {
561 ssize_t this = min((ssize_t)(priv->iv[i].iov_len), total);
562
563 if (copy_to_user(priv->iv[i].iov_base, to_copy, this)) {
564 if (len == 0)
565 len = -EFAULT;
566 break;
567 }
568
569 total -= this;
570 len += this;
571 to_copy += this;
572 if (total == 0)
573 break;
574 }
575 kfree(priv->buf);
576 kfree(priv);
577 return len;
578 }
579
580 static void ep_aio_complete(struct usb_ep *ep, struct usb_request *req)
581 {
582 struct kiocb *iocb = req->context;
583 struct kiocb_priv *priv = iocb->private;
584 struct ep_data *epdata = priv->epdata;
585
586 /* lock against disconnect (and ideally, cancel) */
587 spin_lock(&epdata->dev->lock);
588 priv->req = NULL;
589 priv->epdata = NULL;
590
591 /* if this was a write or a read returning no data then we
592 * don't need to copy anything to userspace, so we can
593 * complete the aio request immediately.
594 */
595 if (priv->iv == NULL || unlikely(req->actual == 0)) {
596 kfree(req->buf);
597 kfree(priv);
598 iocb->private = NULL;
599 /* aio_complete() reports bytes-transferred _and_ faults */
600 aio_complete(iocb, req->actual ? req->actual : req->status,
601 req->status);
602 } else {
603 /* retry() won't report both; so we hide some faults */
604 if (unlikely(0 != req->status))
605 DBG(epdata->dev, "%s fault %d len %d\n",
606 ep->name, req->status, req->actual);
607
608 priv->buf = req->buf;
609 priv->actual = req->actual;
610 kick_iocb(iocb);
611 }
612 spin_unlock(&epdata->dev->lock);
613
614 usb_ep_free_request(ep, req);
615 put_ep(epdata);
616 }
617
618 static ssize_t
619 ep_aio_rwtail(
620 struct kiocb *iocb,
621 char *buf,
622 size_t len,
623 struct ep_data *epdata,
624 const struct iovec *iv,
625 unsigned long nr_segs
626 )
627 {
628 struct kiocb_priv *priv;
629 struct usb_request *req;
630 ssize_t value;
631
632 priv = kmalloc(sizeof *priv, GFP_KERNEL);
633 if (!priv) {
634 value = -ENOMEM;
635 fail:
636 kfree(buf);
637 return value;
638 }
639 iocb->private = priv;
640 priv->iv = iv;
641 priv->nr_segs = nr_segs;
642
643 value = get_ready_ep(iocb->ki_filp->f_flags, epdata);
644 if (unlikely(value < 0)) {
645 kfree(priv);
646 goto fail;
647 }
648
649 iocb->ki_cancel = ep_aio_cancel;
650 get_ep(epdata);
651 priv->epdata = epdata;
652 priv->actual = 0;
653
654 /* each kiocb is coupled to one usb_request, but we can't
655 * allocate or submit those if the host disconnected.
656 */
657 spin_lock_irq(&epdata->dev->lock);
658 if (likely(epdata->ep)) {
659 req = usb_ep_alloc_request(epdata->ep, GFP_ATOMIC);
660 if (likely(req)) {
661 priv->req = req;
662 req->buf = buf;
663 req->length = len;
664 req->complete = ep_aio_complete;
665 req->context = iocb;
666 value = usb_ep_queue(epdata->ep, req, GFP_ATOMIC);
667 if (unlikely(0 != value))
668 usb_ep_free_request(epdata->ep, req);
669 } else
670 value = -EAGAIN;
671 } else
672 value = -ENODEV;
673 spin_unlock_irq(&epdata->dev->lock);
674
675 up(&epdata->lock);
676
677 if (unlikely(value)) {
678 kfree(priv);
679 put_ep(epdata);
680 } else
681 value = (iv ? -EIOCBRETRY : -EIOCBQUEUED);
682 return value;
683 }
684
685 static ssize_t
686 ep_aio_read(struct kiocb *iocb, const struct iovec *iov,
687 unsigned long nr_segs, loff_t o)
688 {
689 struct ep_data *epdata = iocb->ki_filp->private_data;
690 char *buf;
691
692 if (unlikely(usb_endpoint_dir_in(&epdata->desc)))
693 return -EINVAL;
694
695 buf = kmalloc(iocb->ki_left, GFP_KERNEL);
696 if (unlikely(!buf))
697 return -ENOMEM;
698
699 iocb->ki_retry = ep_aio_read_retry;
700 return ep_aio_rwtail(iocb, buf, iocb->ki_left, epdata, iov, nr_segs);
701 }
702
703 static ssize_t
704 ep_aio_write(struct kiocb *iocb, const struct iovec *iov,
705 unsigned long nr_segs, loff_t o)
706 {
707 struct ep_data *epdata = iocb->ki_filp->private_data;
708 char *buf;
709 size_t len = 0;
710 int i = 0;
711
712 if (unlikely(!usb_endpoint_dir_in(&epdata->desc)))
713 return -EINVAL;
714
715 buf = kmalloc(iocb->ki_left, GFP_KERNEL);
716 if (unlikely(!buf))
717 return -ENOMEM;
718
719 for (i=0; i < nr_segs; i++) {
720 if (unlikely(copy_from_user(&buf[len], iov[i].iov_base,
721 iov[i].iov_len) != 0)) {
722 kfree(buf);
723 return -EFAULT;
724 }
725 len += iov[i].iov_len;
726 }
727 return ep_aio_rwtail(iocb, buf, len, epdata, NULL, 0);
728 }
729
730 /*----------------------------------------------------------------------*/
731
732 /* used after endpoint configuration */
733 static const struct file_operations ep_io_operations = {
734 .owner = THIS_MODULE,
735 .llseek = no_llseek,
736
737 .read = ep_read,
738 .write = ep_write,
739 .unlocked_ioctl = ep_ioctl,
740 .release = ep_release,
741
742 .aio_read = ep_aio_read,
743 .aio_write = ep_aio_write,
744 };
745
746 /* ENDPOINT INITIALIZATION
747 *
748 * fd = open ("/dev/gadget/$ENDPOINT", O_RDWR)
749 * status = write (fd, descriptors, sizeof descriptors)
750 *
751 * That write establishes the endpoint configuration, configuring
752 * the controller to process bulk, interrupt, or isochronous transfers
753 * at the right maxpacket size, and so on.
754 *
755 * The descriptors are message type 1, identified by a host order u32
756 * at the beginning of what's written. Descriptor order is: full/low
757 * speed descriptor, then optional high speed descriptor.
758 */
759 static ssize_t
760 ep_config (struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
761 {
762 struct ep_data *data = fd->private_data;
763 struct usb_ep *ep;
764 u32 tag;
765 int value, length = len;
766
767 if ((value = down_interruptible (&data->lock)) < 0)
768 return value;
769
770 if (data->state != STATE_EP_READY) {
771 value = -EL2HLT;
772 goto fail;
773 }
774
775 value = len;
776 if (len < USB_DT_ENDPOINT_SIZE + 4)
777 goto fail0;
778
779 /* we might need to change message format someday */
780 if (copy_from_user (&tag, buf, 4)) {
781 goto fail1;
782 }
783 if (tag != 1) {
784 DBG(data->dev, "config %s, bad tag %d\n", data->name, tag);
785 goto fail0;
786 }
787 buf += 4;
788 len -= 4;
789
790 /* NOTE: audio endpoint extensions not accepted here;
791 * just don't include the extra bytes.
792 */
793
794 /* full/low speed descriptor, then high speed */
795 if (copy_from_user (&data->desc, buf, USB_DT_ENDPOINT_SIZE)) {
796 goto fail1;
797 }
798 if (data->desc.bLength != USB_DT_ENDPOINT_SIZE
799 || data->desc.bDescriptorType != USB_DT_ENDPOINT)
800 goto fail0;
801 if (len != USB_DT_ENDPOINT_SIZE) {
802 if (len != 2 * USB_DT_ENDPOINT_SIZE)
803 goto fail0;
804 if (copy_from_user (&data->hs_desc, buf + USB_DT_ENDPOINT_SIZE,
805 USB_DT_ENDPOINT_SIZE)) {
806 goto fail1;
807 }
808 if (data->hs_desc.bLength != USB_DT_ENDPOINT_SIZE
809 || data->hs_desc.bDescriptorType
810 != USB_DT_ENDPOINT) {
811 DBG(data->dev, "config %s, bad hs length or type\n",
812 data->name);
813 goto fail0;
814 }
815 }
816
817 spin_lock_irq (&data->dev->lock);
818 if (data->dev->state == STATE_DEV_UNBOUND) {
819 value = -ENOENT;
820 goto gone;
821 } else if ((ep = data->ep) == NULL) {
822 value = -ENODEV;
823 goto gone;
824 }
825 switch (data->dev->gadget->speed) {
826 case USB_SPEED_LOW:
827 case USB_SPEED_FULL:
828 value = usb_ep_enable (ep, &data->desc);
829 if (value == 0)
830 data->state = STATE_EP_ENABLED;
831 break;
832 #ifdef CONFIG_USB_GADGET_DUALSPEED
833 case USB_SPEED_HIGH:
834 /* fails if caller didn't provide that descriptor... */
835 value = usb_ep_enable (ep, &data->hs_desc);
836 if (value == 0)
837 data->state = STATE_EP_ENABLED;
838 break;
839 #endif
840 default:
841 DBG(data->dev, "unconnected, %s init abandoned\n",
842 data->name);
843 value = -EINVAL;
844 }
845 if (value == 0) {
846 fd->f_op = &ep_io_operations;
847 value = length;
848 }
849 gone:
850 spin_unlock_irq (&data->dev->lock);
851 if (value < 0) {
852 fail:
853 data->desc.bDescriptorType = 0;
854 data->hs_desc.bDescriptorType = 0;
855 }
856 up (&data->lock);
857 return value;
858 fail0:
859 value = -EINVAL;
860 goto fail;
861 fail1:
862 value = -EFAULT;
863 goto fail;
864 }
865
866 static int
867 ep_open (struct inode *inode, struct file *fd)
868 {
869 struct ep_data *data = inode->i_private;
870 int value = -EBUSY;
871
872 if (down_interruptible (&data->lock) != 0)
873 return -EINTR;
874 spin_lock_irq (&data->dev->lock);
875 if (data->dev->state == STATE_DEV_UNBOUND)
876 value = -ENOENT;
877 else if (data->state == STATE_EP_DISABLED) {
878 value = 0;
879 data->state = STATE_EP_READY;
880 get_ep (data);
881 fd->private_data = data;
882 VDEBUG (data->dev, "%s ready\n", data->name);
883 } else
884 DBG (data->dev, "%s state %d\n",
885 data->name, data->state);
886 spin_unlock_irq (&data->dev->lock);
887 up (&data->lock);
888 return value;
889 }
890
891 /* used before endpoint configuration */
892 static const struct file_operations ep_config_operations = {
893 .owner = THIS_MODULE,
894 .llseek = no_llseek,
895
896 .open = ep_open,
897 .write = ep_config,
898 .release = ep_release,
899 };
900
901 /*----------------------------------------------------------------------*/
902
903 /* EP0 IMPLEMENTATION can be partly in userspace.
904 *
905 * Drivers that use this facility receive various events, including
906 * control requests the kernel doesn't handle. Drivers that don't
907 * use this facility may be too simple-minded for real applications.
908 */
909
910 static inline void ep0_readable (struct dev_data *dev)
911 {
912 wake_up (&dev->wait);
913 kill_fasync (&dev->fasync, SIGIO, POLL_IN);
914 }
915
916 static void clean_req (struct usb_ep *ep, struct usb_request *req)
917 {
918 struct dev_data *dev = ep->driver_data;
919
920 if (req->buf != dev->rbuf) {
921 kfree(req->buf);
922 req->buf = dev->rbuf;
923 req->dma = DMA_ADDR_INVALID;
924 }
925 req->complete = epio_complete;
926 dev->setup_out_ready = 0;
927 }
928
929 static void ep0_complete (struct usb_ep *ep, struct usb_request *req)
930 {
931 struct dev_data *dev = ep->driver_data;
932 unsigned long flags;
933 int free = 1;
934
935 /* for control OUT, data must still get to userspace */
936 spin_lock_irqsave(&dev->lock, flags);
937 if (!dev->setup_in) {
938 dev->setup_out_error = (req->status != 0);
939 if (!dev->setup_out_error)
940 free = 0;
941 dev->setup_out_ready = 1;
942 ep0_readable (dev);
943 }
944
945 /* clean up as appropriate */
946 if (free && req->buf != &dev->rbuf)
947 clean_req (ep, req);
948 req->complete = epio_complete;
949 spin_unlock_irqrestore(&dev->lock, flags);
950 }
951
952 static int setup_req (struct usb_ep *ep, struct usb_request *req, u16 len)
953 {
954 struct dev_data *dev = ep->driver_data;
955
956 if (dev->setup_out_ready) {
957 DBG (dev, "ep0 request busy!\n");
958 return -EBUSY;
959 }
960 if (len > sizeof (dev->rbuf))
961 req->buf = kmalloc(len, GFP_ATOMIC);
962 if (req->buf == NULL) {
963 req->buf = dev->rbuf;
964 return -ENOMEM;
965 }
966 req->complete = ep0_complete;
967 req->length = len;
968 req->zero = 0;
969 return 0;
970 }
971
972 static ssize_t
973 ep0_read (struct file *fd, char __user *buf, size_t len, loff_t *ptr)
974 {
975 struct dev_data *dev = fd->private_data;
976 ssize_t retval;
977 enum ep0_state state;
978
979 spin_lock_irq (&dev->lock);
980
981 /* report fd mode change before acting on it */
982 if (dev->setup_abort) {
983 dev->setup_abort = 0;
984 retval = -EIDRM;
985 goto done;
986 }
987
988 /* control DATA stage */
989 if ((state = dev->state) == STATE_DEV_SETUP) {
990
991 if (dev->setup_in) { /* stall IN */
992 VDEBUG(dev, "ep0in stall\n");
993 (void) usb_ep_set_halt (dev->gadget->ep0);
994 retval = -EL2HLT;
995 dev->state = STATE_DEV_CONNECTED;
996
997 } else if (len == 0) { /* ack SET_CONFIGURATION etc */
998 struct usb_ep *ep = dev->gadget->ep0;
999 struct usb_request *req = dev->req;
1000
1001 if ((retval = setup_req (ep, req, 0)) == 0)
1002 retval = usb_ep_queue (ep, req, GFP_ATOMIC);
1003 dev->state = STATE_DEV_CONNECTED;
1004
1005 /* assume that was SET_CONFIGURATION */
1006 if (dev->current_config) {
1007 unsigned power;
1008
1009 if (gadget_is_dualspeed(dev->gadget)
1010 && (dev->gadget->speed
1011 == USB_SPEED_HIGH))
1012 power = dev->hs_config->bMaxPower;
1013 else
1014 power = dev->config->bMaxPower;
1015 usb_gadget_vbus_draw(dev->gadget, 2 * power);
1016 }
1017
1018 } else { /* collect OUT data */
1019 if ((fd->f_flags & O_NONBLOCK) != 0
1020 && !dev->setup_out_ready) {
1021 retval = -EAGAIN;
1022 goto done;
1023 }
1024 spin_unlock_irq (&dev->lock);
1025 retval = wait_event_interruptible (dev->wait,
1026 dev->setup_out_ready != 0);
1027
1028 /* FIXME state could change from under us */
1029 spin_lock_irq (&dev->lock);
1030 if (retval)
1031 goto done;
1032
1033 if (dev->state != STATE_DEV_SETUP) {
1034 retval = -ECANCELED;
1035 goto done;
1036 }
1037 dev->state = STATE_DEV_CONNECTED;
1038
1039 if (dev->setup_out_error)
1040 retval = -EIO;
1041 else {
1042 len = min (len, (size_t)dev->req->actual);
1043 // FIXME don't call this with the spinlock held ...
1044 if (copy_to_user (buf, dev->req->buf, len))
1045 retval = -EFAULT;
1046 clean_req (dev->gadget->ep0, dev->req);
1047 /* NOTE userspace can't yet choose to stall */
1048 }
1049 }
1050 goto done;
1051 }
1052
1053 /* else normal: return event data */
1054 if (len < sizeof dev->event [0]) {
1055 retval = -EINVAL;
1056 goto done;
1057 }
1058 len -= len % sizeof (struct usb_gadgetfs_event);
1059 dev->usermode_setup = 1;
1060
1061 scan:
1062 /* return queued events right away */
1063 if (dev->ev_next != 0) {
1064 unsigned i, n;
1065
1066 n = len / sizeof (struct usb_gadgetfs_event);
1067 if (dev->ev_next < n)
1068 n = dev->ev_next;
1069
1070 /* ep0 i/o has special semantics during STATE_DEV_SETUP */
1071 for (i = 0; i < n; i++) {
1072 if (dev->event [i].type == GADGETFS_SETUP) {
1073 dev->state = STATE_DEV_SETUP;
1074 n = i + 1;
1075 break;
1076 }
1077 }
1078 spin_unlock_irq (&dev->lock);
1079 len = n * sizeof (struct usb_gadgetfs_event);
1080 if (copy_to_user (buf, &dev->event, len))
1081 retval = -EFAULT;
1082 else
1083 retval = len;
1084 if (len > 0) {
1085 /* NOTE this doesn't guard against broken drivers;
1086 * concurrent ep0 readers may lose events.
1087 */
1088 spin_lock_irq (&dev->lock);
1089 if (dev->ev_next > n) {
1090 memmove(&dev->event[0], &dev->event[n],
1091 sizeof (struct usb_gadgetfs_event)
1092 * (dev->ev_next - n));
1093 }
1094 dev->ev_next -= n;
1095 spin_unlock_irq (&dev->lock);
1096 }
1097 return retval;
1098 }
1099 if (fd->f_flags & O_NONBLOCK) {
1100 retval = -EAGAIN;
1101 goto done;
1102 }
1103
1104 switch (state) {
1105 default:
1106 DBG (dev, "fail %s, state %d\n", __func__, state);
1107 retval = -ESRCH;
1108 break;
1109 case STATE_DEV_UNCONNECTED:
1110 case STATE_DEV_CONNECTED:
1111 spin_unlock_irq (&dev->lock);
1112 DBG (dev, "%s wait\n", __func__);
1113
1114 /* wait for events */
1115 retval = wait_event_interruptible (dev->wait,
1116 dev->ev_next != 0);
1117 if (retval < 0)
1118 return retval;
1119 spin_lock_irq (&dev->lock);
1120 goto scan;
1121 }
1122
1123 done:
1124 spin_unlock_irq (&dev->lock);
1125 return retval;
1126 }
1127
1128 static struct usb_gadgetfs_event *
1129 next_event (struct dev_data *dev, enum usb_gadgetfs_event_type type)
1130 {
1131 struct usb_gadgetfs_event *event;
1132 unsigned i;
1133
1134 switch (type) {
1135 /* these events purge the queue */
1136 case GADGETFS_DISCONNECT:
1137 if (dev->state == STATE_DEV_SETUP)
1138 dev->setup_abort = 1;
1139 // FALL THROUGH
1140 case GADGETFS_CONNECT:
1141 dev->ev_next = 0;
1142 break;
1143 case GADGETFS_SETUP: /* previous request timed out */
1144 case GADGETFS_SUSPEND: /* same effect */
1145 /* these events can't be repeated */
1146 for (i = 0; i != dev->ev_next; i++) {
1147 if (dev->event [i].type != type)
1148 continue;
1149 DBG(dev, "discard old event[%d] %d\n", i, type);
1150 dev->ev_next--;
1151 if (i == dev->ev_next)
1152 break;
1153 /* indices start at zero, for simplicity */
1154 memmove (&dev->event [i], &dev->event [i + 1],
1155 sizeof (struct usb_gadgetfs_event)
1156 * (dev->ev_next - i));
1157 }
1158 break;
1159 default:
1160 BUG ();
1161 }
1162 VDEBUG(dev, "event[%d] = %d\n", dev->ev_next, type);
1163 event = &dev->event [dev->ev_next++];
1164 BUG_ON (dev->ev_next > N_EVENT);
1165 memset (event, 0, sizeof *event);
1166 event->type = type;
1167 return event;
1168 }
1169
1170 static ssize_t
1171 ep0_write (struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
1172 {
1173 struct dev_data *dev = fd->private_data;
1174 ssize_t retval = -ESRCH;
1175
1176 spin_lock_irq (&dev->lock);
1177
1178 /* report fd mode change before acting on it */
1179 if (dev->setup_abort) {
1180 dev->setup_abort = 0;
1181 retval = -EIDRM;
1182
1183 /* data and/or status stage for control request */
1184 } else if (dev->state == STATE_DEV_SETUP) {
1185
1186 /* IN DATA+STATUS caller makes len <= wLength */
1187 if (dev->setup_in) {
1188 retval = setup_req (dev->gadget->ep0, dev->req, len);
1189 if (retval == 0) {
1190 dev->state = STATE_DEV_CONNECTED;
1191 spin_unlock_irq (&dev->lock);
1192 if (copy_from_user (dev->req->buf, buf, len))
1193 retval = -EFAULT;
1194 else {
1195 if (len < dev->setup_wLength)
1196 dev->req->zero = 1;
1197 retval = usb_ep_queue (
1198 dev->gadget->ep0, dev->req,
1199 GFP_KERNEL);
1200 }
1201 if (retval < 0) {
1202 spin_lock_irq (&dev->lock);
1203 clean_req (dev->gadget->ep0, dev->req);
1204 spin_unlock_irq (&dev->lock);
1205 } else
1206 retval = len;
1207
1208 return retval;
1209 }
1210
1211 /* can stall some OUT transfers */
1212 } else if (dev->setup_can_stall) {
1213 VDEBUG(dev, "ep0out stall\n");
1214 (void) usb_ep_set_halt (dev->gadget->ep0);
1215 retval = -EL2HLT;
1216 dev->state = STATE_DEV_CONNECTED;
1217 } else {
1218 DBG(dev, "bogus ep0out stall!\n");
1219 }
1220 } else
1221 DBG (dev, "fail %s, state %d\n", __func__, dev->state);
1222
1223 spin_unlock_irq (&dev->lock);
1224 return retval;
1225 }
1226
1227 static int
1228 ep0_fasync (int f, struct file *fd, int on)
1229 {
1230 struct dev_data *dev = fd->private_data;
1231 // caller must F_SETOWN before signal delivery happens
1232 VDEBUG (dev, "%s %s\n", __func__, on ? "on" : "off");
1233 return fasync_helper (f, fd, on, &dev->fasync);
1234 }
1235
1236 static struct usb_gadget_driver gadgetfs_driver;
1237
1238 static int
1239 dev_release (struct inode *inode, struct file *fd)
1240 {
1241 struct dev_data *dev = fd->private_data;
1242
1243 /* closing ep0 === shutdown all */
1244
1245 usb_gadget_unregister_driver (&gadgetfs_driver);
1246
1247 /* at this point "good" hardware has disconnected the
1248 * device from USB; the host won't see it any more.
1249 * alternatively, all host requests will time out.
1250 */
1251
1252 kfree (dev->buf);
1253 dev->buf = NULL;
1254 put_dev (dev);
1255
1256 /* other endpoints were all decoupled from this device */
1257 spin_lock_irq(&dev->lock);
1258 dev->state = STATE_DEV_DISABLED;
1259 spin_unlock_irq(&dev->lock);
1260 return 0;
1261 }
1262
1263 static unsigned int
1264 ep0_poll (struct file *fd, poll_table *wait)
1265 {
1266 struct dev_data *dev = fd->private_data;
1267 int mask = 0;
1268
1269 poll_wait(fd, &dev->wait, wait);
1270
1271 spin_lock_irq (&dev->lock);
1272
1273 /* report fd mode change before acting on it */
1274 if (dev->setup_abort) {
1275 dev->setup_abort = 0;
1276 mask = POLLHUP;
1277 goto out;
1278 }
1279
1280 if (dev->state == STATE_DEV_SETUP) {
1281 if (dev->setup_in || dev->setup_can_stall)
1282 mask = POLLOUT;
1283 } else {
1284 if (dev->ev_next != 0)
1285 mask = POLLIN;
1286 }
1287 out:
1288 spin_unlock_irq(&dev->lock);
1289 return mask;
1290 }
1291
1292 static long dev_ioctl (struct file *fd, unsigned code, unsigned long value)
1293 {
1294 struct dev_data *dev = fd->private_data;
1295 struct usb_gadget *gadget = dev->gadget;
1296 long ret = -ENOTTY;
1297
1298 if (gadget->ops->ioctl) {
1299 lock_kernel();
1300 ret = gadget->ops->ioctl (gadget, code, value);
1301 unlock_kernel();
1302 }
1303 return ret;
1304 }
1305
1306 /* used after device configuration */
1307 static const struct file_operations ep0_io_operations = {
1308 .owner = THIS_MODULE,
1309 .llseek = no_llseek,
1310
1311 .read = ep0_read,
1312 .write = ep0_write,
1313 .fasync = ep0_fasync,
1314 .poll = ep0_poll,
1315 .unlocked_ioctl = dev_ioctl,
1316 .release = dev_release,
1317 };
1318
1319 /*----------------------------------------------------------------------*/
1320
1321 /* The in-kernel gadget driver handles most ep0 issues, in particular
1322 * enumerating the single configuration (as provided from user space).
1323 *
1324 * Unrecognized ep0 requests may be handled in user space.
1325 */
1326
1327 #ifdef CONFIG_USB_GADGET_DUALSPEED
1328 static void make_qualifier (struct dev_data *dev)
1329 {
1330 struct usb_qualifier_descriptor qual;
1331 struct usb_device_descriptor *desc;
1332
1333 qual.bLength = sizeof qual;
1334 qual.bDescriptorType = USB_DT_DEVICE_QUALIFIER;
1335 qual.bcdUSB = cpu_to_le16 (0x0200);
1336
1337 desc = dev->dev;
1338 qual.bDeviceClass = desc->bDeviceClass;
1339 qual.bDeviceSubClass = desc->bDeviceSubClass;
1340 qual.bDeviceProtocol = desc->bDeviceProtocol;
1341
1342 /* assumes ep0 uses the same value for both speeds ... */
1343 qual.bMaxPacketSize0 = desc->bMaxPacketSize0;
1344
1345 qual.bNumConfigurations = 1;
1346 qual.bRESERVED = 0;
1347
1348 memcpy (dev->rbuf, &qual, sizeof qual);
1349 }
1350 #endif
1351
1352 static int
1353 config_buf (struct dev_data *dev, u8 type, unsigned index)
1354 {
1355 int len;
1356 int hs = 0;
1357
1358 /* only one configuration */
1359 if (index > 0)
1360 return -EINVAL;
1361
1362 if (gadget_is_dualspeed(dev->gadget)) {
1363 hs = (dev->gadget->speed == USB_SPEED_HIGH);
1364 if (type == USB_DT_OTHER_SPEED_CONFIG)
1365 hs = !hs;
1366 }
1367 if (hs) {
1368 dev->req->buf = dev->hs_config;
1369 len = le16_to_cpu(dev->hs_config->wTotalLength);
1370 } else {
1371 dev->req->buf = dev->config;
1372 len = le16_to_cpu(dev->config->wTotalLength);
1373 }
1374 ((u8 *)dev->req->buf) [1] = type;
1375 return len;
1376 }
1377
1378 static int
1379 gadgetfs_setup (struct usb_gadget *gadget, const struct usb_ctrlrequest *ctrl)
1380 {
1381 struct dev_data *dev = get_gadget_data (gadget);
1382 struct usb_request *req = dev->req;
1383 int value = -EOPNOTSUPP;
1384 struct usb_gadgetfs_event *event;
1385 u16 w_value = le16_to_cpu(ctrl->wValue);
1386 u16 w_length = le16_to_cpu(ctrl->wLength);
1387
1388 spin_lock (&dev->lock);
1389 dev->setup_abort = 0;
1390 if (dev->state == STATE_DEV_UNCONNECTED) {
1391 if (gadget_is_dualspeed(gadget)
1392 && gadget->speed == USB_SPEED_HIGH
1393 && dev->hs_config == NULL) {
1394 spin_unlock(&dev->lock);
1395 ERROR (dev, "no high speed config??\n");
1396 return -EINVAL;
1397 }
1398
1399 dev->state = STATE_DEV_CONNECTED;
1400 dev->dev->bMaxPacketSize0 = gadget->ep0->maxpacket;
1401
1402 INFO (dev, "connected\n");
1403 event = next_event (dev, GADGETFS_CONNECT);
1404 event->u.speed = gadget->speed;
1405 ep0_readable (dev);
1406
1407 /* host may have given up waiting for response. we can miss control
1408 * requests handled lower down (device/endpoint status and features);
1409 * then ep0_{read,write} will report the wrong status. controller
1410 * driver will have aborted pending i/o.
1411 */
1412 } else if (dev->state == STATE_DEV_SETUP)
1413 dev->setup_abort = 1;
1414
1415 req->buf = dev->rbuf;
1416 req->dma = DMA_ADDR_INVALID;
1417 req->context = NULL;
1418 value = -EOPNOTSUPP;
1419 switch (ctrl->bRequest) {
1420
1421 case USB_REQ_GET_DESCRIPTOR:
1422 if (ctrl->bRequestType != USB_DIR_IN)
1423 goto unrecognized;
1424 switch (w_value >> 8) {
1425
1426 case USB_DT_DEVICE:
1427 value = min (w_length, (u16) sizeof *dev->dev);
1428 req->buf = dev->dev;
1429 break;
1430 #ifdef CONFIG_USB_GADGET_DUALSPEED
1431 case USB_DT_DEVICE_QUALIFIER:
1432 if (!dev->hs_config)
1433 break;
1434 value = min (w_length, (u16)
1435 sizeof (struct usb_qualifier_descriptor));
1436 make_qualifier (dev);
1437 break;
1438 case USB_DT_OTHER_SPEED_CONFIG:
1439 // FALLTHROUGH
1440 #endif
1441 case USB_DT_CONFIG:
1442 value = config_buf (dev,
1443 w_value >> 8,
1444 w_value & 0xff);
1445 if (value >= 0)
1446 value = min (w_length, (u16) value);
1447 break;
1448 case USB_DT_STRING:
1449 goto unrecognized;
1450
1451 default: // all others are errors
1452 break;
1453 }
1454 break;
1455
1456 /* currently one config, two speeds */
1457 case USB_REQ_SET_CONFIGURATION:
1458 if (ctrl->bRequestType != 0)
1459 goto unrecognized;
1460 if (0 == (u8) w_value) {
1461 value = 0;
1462 dev->current_config = 0;
1463 usb_gadget_vbus_draw(gadget, 8 /* mA */ );
1464 // user mode expected to disable endpoints
1465 } else {
1466 u8 config, power;
1467
1468 if (gadget_is_dualspeed(gadget)
1469 && gadget->speed == USB_SPEED_HIGH) {
1470 config = dev->hs_config->bConfigurationValue;
1471 power = dev->hs_config->bMaxPower;
1472 } else {
1473 config = dev->config->bConfigurationValue;
1474 power = dev->config->bMaxPower;
1475 }
1476
1477 if (config == (u8) w_value) {
1478 value = 0;
1479 dev->current_config = config;
1480 usb_gadget_vbus_draw(gadget, 2 * power);
1481 }
1482 }
1483
1484 /* report SET_CONFIGURATION like any other control request,
1485 * except that usermode may not stall this. the next
1486 * request mustn't be allowed start until this finishes:
1487 * endpoints and threads set up, etc.
1488 *
1489 * NOTE: older PXA hardware (before PXA 255: without UDCCFR)
1490 * has bad/racey automagic that prevents synchronizing here.
1491 * even kernel mode drivers often miss them.
1492 */
1493 if (value == 0) {
1494 INFO (dev, "configuration #%d\n", dev->current_config);
1495 if (dev->usermode_setup) {
1496 dev->setup_can_stall = 0;
1497 goto delegate;
1498 }
1499 }
1500 break;
1501
1502 #ifndef CONFIG_USB_GADGET_PXA25X
1503 /* PXA automagically handles this request too */
1504 case USB_REQ_GET_CONFIGURATION:
1505 if (ctrl->bRequestType != 0x80)
1506 goto unrecognized;
1507 *(u8 *)req->buf = dev->current_config;
1508 value = min (w_length, (u16) 1);
1509 break;
1510 #endif
1511
1512 default:
1513 unrecognized:
1514 VDEBUG (dev, "%s req%02x.%02x v%04x i%04x l%d\n",
1515 dev->usermode_setup ? "delegate" : "fail",
1516 ctrl->bRequestType, ctrl->bRequest,
1517 w_value, le16_to_cpu(ctrl->wIndex), w_length);
1518
1519 /* if there's an ep0 reader, don't stall */
1520 if (dev->usermode_setup) {
1521 dev->setup_can_stall = 1;
1522 delegate:
1523 dev->setup_in = (ctrl->bRequestType & USB_DIR_IN)
1524 ? 1 : 0;
1525 dev->setup_wLength = w_length;
1526 dev->setup_out_ready = 0;
1527 dev->setup_out_error = 0;
1528 value = 0;
1529
1530 /* read DATA stage for OUT right away */
1531 if (unlikely (!dev->setup_in && w_length)) {
1532 value = setup_req (gadget->ep0, dev->req,
1533 w_length);
1534 if (value < 0)
1535 break;
1536 value = usb_ep_queue (gadget->ep0, dev->req,
1537 GFP_ATOMIC);
1538 if (value < 0) {
1539 clean_req (gadget->ep0, dev->req);
1540 break;
1541 }
1542
1543 /* we can't currently stall these */
1544 dev->setup_can_stall = 0;
1545 }
1546
1547 /* state changes when reader collects event */
1548 event = next_event (dev, GADGETFS_SETUP);
1549 event->u.setup = *ctrl;
1550 ep0_readable (dev);
1551 spin_unlock (&dev->lock);
1552 return 0;
1553 }
1554 }
1555
1556 /* proceed with data transfer and status phases? */
1557 if (value >= 0 && dev->state != STATE_DEV_SETUP) {
1558 req->length = value;
1559 req->zero = value < w_length;
1560 value = usb_ep_queue (gadget->ep0, req, GFP_ATOMIC);
1561 if (value < 0) {
1562 DBG (dev, "ep_queue --> %d\n", value);
1563 req->status = 0;
1564 }
1565 }
1566
1567 /* device stalls when value < 0 */
1568 spin_unlock (&dev->lock);
1569 return value;
1570 }
1571
1572 static void destroy_ep_files (struct dev_data *dev)
1573 {
1574 struct list_head *entry, *tmp;
1575
1576 DBG (dev, "%s %d\n", __func__, dev->state);
1577
1578 /* dev->state must prevent interference */
1579 restart:
1580 spin_lock_irq (&dev->lock);
1581 list_for_each_safe (entry, tmp, &dev->epfiles) {
1582 struct ep_data *ep;
1583 struct inode *parent;
1584 struct dentry *dentry;
1585
1586 /* break link to FS */
1587 ep = list_entry (entry, struct ep_data, epfiles);
1588 list_del_init (&ep->epfiles);
1589 dentry = ep->dentry;
1590 ep->dentry = NULL;
1591 parent = dentry->d_parent->d_inode;
1592
1593 /* break link to controller */
1594 if (ep->state == STATE_EP_ENABLED)
1595 (void) usb_ep_disable (ep->ep);
1596 ep->state = STATE_EP_UNBOUND;
1597 usb_ep_free_request (ep->ep, ep->req);
1598 ep->ep = NULL;
1599 wake_up (&ep->wait);
1600 put_ep (ep);
1601
1602 spin_unlock_irq (&dev->lock);
1603
1604 /* break link to dcache */
1605 mutex_lock (&parent->i_mutex);
1606 d_delete (dentry);
1607 dput (dentry);
1608 mutex_unlock (&parent->i_mutex);
1609
1610 /* fds may still be open */
1611 goto restart;
1612 }
1613 spin_unlock_irq (&dev->lock);
1614 }
1615
1616
1617 static struct inode *
1618 gadgetfs_create_file (struct super_block *sb, char const *name,
1619 void *data, const struct file_operations *fops,
1620 struct dentry **dentry_p);
1621
1622 static int activate_ep_files (struct dev_data *dev)
1623 {
1624 struct usb_ep *ep;
1625 struct ep_data *data;
1626
1627 gadget_for_each_ep (ep, dev->gadget) {
1628
1629 data = kzalloc(sizeof(*data), GFP_KERNEL);
1630 if (!data)
1631 goto enomem0;
1632 data->state = STATE_EP_DISABLED;
1633 init_MUTEX (&data->lock);
1634 init_waitqueue_head (&data->wait);
1635
1636 strncpy (data->name, ep->name, sizeof (data->name) - 1);
1637 atomic_set (&data->count, 1);
1638 data->dev = dev;
1639 get_dev (dev);
1640
1641 data->ep = ep;
1642 ep->driver_data = data;
1643
1644 data->req = usb_ep_alloc_request (ep, GFP_KERNEL);
1645 if (!data->req)
1646 goto enomem1;
1647
1648 data->inode = gadgetfs_create_file (dev->sb, data->name,
1649 data, &ep_config_operations,
1650 &data->dentry);
1651 if (!data->inode)
1652 goto enomem2;
1653 list_add_tail (&data->epfiles, &dev->epfiles);
1654 }
1655 return 0;
1656
1657 enomem2:
1658 usb_ep_free_request (ep, data->req);
1659 enomem1:
1660 put_dev (dev);
1661 kfree (data);
1662 enomem0:
1663 DBG (dev, "%s enomem\n", __func__);
1664 destroy_ep_files (dev);
1665 return -ENOMEM;
1666 }
1667
1668 static void
1669 gadgetfs_unbind (struct usb_gadget *gadget)
1670 {
1671 struct dev_data *dev = get_gadget_data (gadget);
1672
1673 DBG (dev, "%s\n", __func__);
1674
1675 spin_lock_irq (&dev->lock);
1676 dev->state = STATE_DEV_UNBOUND;
1677 spin_unlock_irq (&dev->lock);
1678
1679 destroy_ep_files (dev);
1680 gadget->ep0->driver_data = NULL;
1681 set_gadget_data (gadget, NULL);
1682
1683 /* we've already been disconnected ... no i/o is active */
1684 if (dev->req)
1685 usb_ep_free_request (gadget->ep0, dev->req);
1686 DBG (dev, "%s done\n", __func__);
1687 put_dev (dev);
1688 }
1689
1690 static struct dev_data *the_device;
1691
1692 static int
1693 gadgetfs_bind (struct usb_gadget *gadget)
1694 {
1695 struct dev_data *dev = the_device;
1696
1697 if (!dev)
1698 return -ESRCH;
1699 if (0 != strcmp (CHIP, gadget->name)) {
1700 pr_err("%s expected %s controller not %s\n",
1701 shortname, CHIP, gadget->name);
1702 return -ENODEV;
1703 }
1704
1705 set_gadget_data (gadget, dev);
1706 dev->gadget = gadget;
1707 gadget->ep0->driver_data = dev;
1708 dev->dev->bMaxPacketSize0 = gadget->ep0->maxpacket;
1709
1710 /* preallocate control response and buffer */
1711 dev->req = usb_ep_alloc_request (gadget->ep0, GFP_KERNEL);
1712 if (!dev->req)
1713 goto enomem;
1714 dev->req->context = NULL;
1715 dev->req->complete = epio_complete;
1716
1717 if (activate_ep_files (dev) < 0)
1718 goto enomem;
1719
1720 INFO (dev, "bound to %s driver\n", gadget->name);
1721 spin_lock_irq(&dev->lock);
1722 dev->state = STATE_DEV_UNCONNECTED;
1723 spin_unlock_irq(&dev->lock);
1724 get_dev (dev);
1725 return 0;
1726
1727 enomem:
1728 gadgetfs_unbind (gadget);
1729 return -ENOMEM;
1730 }
1731
1732 static void
1733 gadgetfs_disconnect (struct usb_gadget *gadget)
1734 {
1735 struct dev_data *dev = get_gadget_data (gadget);
1736
1737 spin_lock (&dev->lock);
1738 if (dev->state == STATE_DEV_UNCONNECTED)
1739 goto exit;
1740 dev->state = STATE_DEV_UNCONNECTED;
1741
1742 INFO (dev, "disconnected\n");
1743 next_event (dev, GADGETFS_DISCONNECT);
1744 ep0_readable (dev);
1745 exit:
1746 spin_unlock (&dev->lock);
1747 }
1748
1749 static void
1750 gadgetfs_suspend (struct usb_gadget *gadget)
1751 {
1752 struct dev_data *dev = get_gadget_data (gadget);
1753
1754 INFO (dev, "suspended from state %d\n", dev->state);
1755 spin_lock (&dev->lock);
1756 switch (dev->state) {
1757 case STATE_DEV_SETUP: // VERY odd... host died??
1758 case STATE_DEV_CONNECTED:
1759 case STATE_DEV_UNCONNECTED:
1760 next_event (dev, GADGETFS_SUSPEND);
1761 ep0_readable (dev);
1762 /* FALLTHROUGH */
1763 default:
1764 break;
1765 }
1766 spin_unlock (&dev->lock);
1767 }
1768
1769 static struct usb_gadget_driver gadgetfs_driver = {
1770 #ifdef CONFIG_USB_GADGET_DUALSPEED
1771 .speed = USB_SPEED_HIGH,
1772 #else
1773 .speed = USB_SPEED_FULL,
1774 #endif
1775 .function = (char *) driver_desc,
1776 .bind = gadgetfs_bind,
1777 .unbind = gadgetfs_unbind,
1778 .setup = gadgetfs_setup,
1779 .disconnect = gadgetfs_disconnect,
1780 .suspend = gadgetfs_suspend,
1781
1782 .driver = {
1783 .name = (char *) shortname,
1784 },
1785 };
1786
1787 /*----------------------------------------------------------------------*/
1788
1789 static void gadgetfs_nop(struct usb_gadget *arg) { }
1790
1791 static int gadgetfs_probe (struct usb_gadget *gadget)
1792 {
1793 CHIP = gadget->name;
1794 return -EISNAM;
1795 }
1796
1797 static struct usb_gadget_driver probe_driver = {
1798 .speed = USB_SPEED_HIGH,
1799 .bind = gadgetfs_probe,
1800 .unbind = gadgetfs_nop,
1801 .setup = (void *)gadgetfs_nop,
1802 .disconnect = gadgetfs_nop,
1803 .driver = {
1804 .name = "nop",
1805 },
1806 };
1807
1808
1809 /* DEVICE INITIALIZATION
1810 *
1811 * fd = open ("/dev/gadget/$CHIP", O_RDWR)
1812 * status = write (fd, descriptors, sizeof descriptors)
1813 *
1814 * That write establishes the device configuration, so the kernel can
1815 * bind to the controller ... guaranteeing it can handle enumeration
1816 * at all necessary speeds. Descriptor order is:
1817 *
1818 * . message tag (u32, host order) ... for now, must be zero; it
1819 * would change to support features like multi-config devices
1820 * . full/low speed config ... all wTotalLength bytes (with interface,
1821 * class, altsetting, endpoint, and other descriptors)
1822 * . high speed config ... all descriptors, for high speed operation;
1823 * this one's optional except for high-speed hardware
1824 * . device descriptor
1825 *
1826 * Endpoints are not yet enabled. Drivers must wait until device
1827 * configuration and interface altsetting changes create
1828 * the need to configure (or unconfigure) them.
1829 *
1830 * After initialization, the device stays active for as long as that
1831 * $CHIP file is open. Events must then be read from that descriptor,
1832 * such as configuration notifications.
1833 */
1834
1835 static int is_valid_config (struct usb_config_descriptor *config)
1836 {
1837 return config->bDescriptorType == USB_DT_CONFIG
1838 && config->bLength == USB_DT_CONFIG_SIZE
1839 && config->bConfigurationValue != 0
1840 && (config->bmAttributes & USB_CONFIG_ATT_ONE) != 0
1841 && (config->bmAttributes & USB_CONFIG_ATT_WAKEUP) == 0;
1842 /* FIXME if gadget->is_otg, _must_ include an otg descriptor */
1843 /* FIXME check lengths: walk to end */
1844 }
1845
1846 static ssize_t
1847 dev_config (struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
1848 {
1849 struct dev_data *dev = fd->private_data;
1850 ssize_t value = len, length = len;
1851 unsigned total;
1852 u32 tag;
1853 char *kbuf;
1854
1855 if (len < (USB_DT_CONFIG_SIZE + USB_DT_DEVICE_SIZE + 4))
1856 return -EINVAL;
1857
1858 /* we might need to change message format someday */
1859 if (copy_from_user (&tag, buf, 4))
1860 return -EFAULT;
1861 if (tag != 0)
1862 return -EINVAL;
1863 buf += 4;
1864 length -= 4;
1865
1866 kbuf = kmalloc (length, GFP_KERNEL);
1867 if (!kbuf)
1868 return -ENOMEM;
1869 if (copy_from_user (kbuf, buf, length)) {
1870 kfree (kbuf);
1871 return -EFAULT;
1872 }
1873
1874 spin_lock_irq (&dev->lock);
1875 value = -EINVAL;
1876 if (dev->buf)
1877 goto fail;
1878 dev->buf = kbuf;
1879
1880 /* full or low speed config */
1881 dev->config = (void *) kbuf;
1882 total = le16_to_cpu(dev->config->wTotalLength);
1883 if (!is_valid_config (dev->config) || total >= length)
1884 goto fail;
1885 kbuf += total;
1886 length -= total;
1887
1888 /* optional high speed config */
1889 if (kbuf [1] == USB_DT_CONFIG) {
1890 dev->hs_config = (void *) kbuf;
1891 total = le16_to_cpu(dev->hs_config->wTotalLength);
1892 if (!is_valid_config (dev->hs_config) || total >= length)
1893 goto fail;
1894 kbuf += total;
1895 length -= total;
1896 }
1897
1898 /* could support multiple configs, using another encoding! */
1899
1900 /* device descriptor (tweaked for paranoia) */
1901 if (length != USB_DT_DEVICE_SIZE)
1902 goto fail;
1903 dev->dev = (void *)kbuf;
1904 if (dev->dev->bLength != USB_DT_DEVICE_SIZE
1905 || dev->dev->bDescriptorType != USB_DT_DEVICE
1906 || dev->dev->bNumConfigurations != 1)
1907 goto fail;
1908 dev->dev->bNumConfigurations = 1;
1909 dev->dev->bcdUSB = cpu_to_le16 (0x0200);
1910
1911 /* triggers gadgetfs_bind(); then we can enumerate. */
1912 spin_unlock_irq (&dev->lock);
1913 value = usb_gadget_register_driver (&gadgetfs_driver);
1914 if (value != 0) {
1915 kfree (dev->buf);
1916 dev->buf = NULL;
1917 } else {
1918 /* at this point "good" hardware has for the first time
1919 * let the USB the host see us. alternatively, if users
1920 * unplug/replug that will clear all the error state.
1921 *
1922 * note: everything running before here was guaranteed
1923 * to choke driver model style diagnostics. from here
1924 * on, they can work ... except in cleanup paths that
1925 * kick in after the ep0 descriptor is closed.
1926 */
1927 fd->f_op = &ep0_io_operations;
1928 value = len;
1929 }
1930 return value;
1931
1932 fail:
1933 spin_unlock_irq (&dev->lock);
1934 pr_debug ("%s: %s fail %Zd, %p\n", shortname, __func__, value, dev);
1935 kfree (dev->buf);
1936 dev->buf = NULL;
1937 return value;
1938 }
1939
1940 static int
1941 dev_open (struct inode *inode, struct file *fd)
1942 {
1943 struct dev_data *dev = inode->i_private;
1944 int value = -EBUSY;
1945
1946 spin_lock_irq(&dev->lock);
1947 if (dev->state == STATE_DEV_DISABLED) {
1948 dev->ev_next = 0;
1949 dev->state = STATE_DEV_OPENED;
1950 fd->private_data = dev;
1951 get_dev (dev);
1952 value = 0;
1953 }
1954 spin_unlock_irq(&dev->lock);
1955 return value;
1956 }
1957
1958 static const struct file_operations dev_init_operations = {
1959 .owner = THIS_MODULE,
1960 .llseek = no_llseek,
1961
1962 .open = dev_open,
1963 .write = dev_config,
1964 .fasync = ep0_fasync,
1965 .unlocked_ioctl = dev_ioctl,
1966 .release = dev_release,
1967 };
1968
1969 /*----------------------------------------------------------------------*/
1970
1971 /* FILESYSTEM AND SUPERBLOCK OPERATIONS
1972 *
1973 * Mounting the filesystem creates a controller file, used first for
1974 * device configuration then later for event monitoring.
1975 */
1976
1977
1978 /* FIXME PAM etc could set this security policy without mount options
1979 * if epfiles inherited ownership and permissons from ep0 ...
1980 */
1981
1982 static unsigned default_uid;
1983 static unsigned default_gid;
1984 static unsigned default_perm = S_IRUSR | S_IWUSR;
1985
1986 module_param (default_uid, uint, 0644);
1987 module_param (default_gid, uint, 0644);
1988 module_param (default_perm, uint, 0644);
1989
1990
1991 static struct inode *
1992 gadgetfs_make_inode (struct super_block *sb,
1993 void *data, const struct file_operations *fops,
1994 int mode)
1995 {
1996 struct inode *inode = new_inode (sb);
1997
1998 if (inode) {
1999 inode->i_mode = mode;
2000 inode->i_uid = default_uid;
2001 inode->i_gid = default_gid;
2002 inode->i_atime = inode->i_mtime = inode->i_ctime
2003 = CURRENT_TIME;
2004 inode->i_private = data;
2005 inode->i_fop = fops;
2006 }
2007 return inode;
2008 }
2009
2010 /* creates in fs root directory, so non-renamable and non-linkable.
2011 * so inode and dentry are paired, until device reconfig.
2012 */
2013 static struct inode *
2014 gadgetfs_create_file (struct super_block *sb, char const *name,
2015 void *data, const struct file_operations *fops,
2016 struct dentry **dentry_p)
2017 {
2018 struct dentry *dentry;
2019 struct inode *inode;
2020
2021 dentry = d_alloc_name(sb->s_root, name);
2022 if (!dentry)
2023 return NULL;
2024
2025 inode = gadgetfs_make_inode (sb, data, fops,
2026 S_IFREG | (default_perm & S_IRWXUGO));
2027 if (!inode) {
2028 dput(dentry);
2029 return NULL;
2030 }
2031 d_add (dentry, inode);
2032 *dentry_p = dentry;
2033 return inode;
2034 }
2035
2036 static struct super_operations gadget_fs_operations = {
2037 .statfs = simple_statfs,
2038 .drop_inode = generic_delete_inode,
2039 };
2040
2041 static int
2042 gadgetfs_fill_super (struct super_block *sb, void *opts, int silent)
2043 {
2044 struct inode *inode;
2045 struct dentry *d;
2046 struct dev_data *dev;
2047
2048 if (the_device)
2049 return -ESRCH;
2050
2051 /* fake probe to determine $CHIP */
2052 (void) usb_gadget_register_driver (&probe_driver);
2053 if (!CHIP)
2054 return -ENODEV;
2055
2056 /* superblock */
2057 sb->s_blocksize = PAGE_CACHE_SIZE;
2058 sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
2059 sb->s_magic = GADGETFS_MAGIC;
2060 sb->s_op = &gadget_fs_operations;
2061 sb->s_time_gran = 1;
2062
2063 /* root inode */
2064 inode = gadgetfs_make_inode (sb,
2065 NULL, &simple_dir_operations,
2066 S_IFDIR | S_IRUGO | S_IXUGO);
2067 if (!inode)
2068 goto enomem0;
2069 inode->i_op = &simple_dir_inode_operations;
2070 if (!(d = d_alloc_root (inode)))
2071 goto enomem1;
2072 sb->s_root = d;
2073
2074 /* the ep0 file is named after the controller we expect;
2075 * user mode code can use it for sanity checks, like we do.
2076 */
2077 dev = dev_new ();
2078 if (!dev)
2079 goto enomem2;
2080
2081 dev->sb = sb;
2082 if (!gadgetfs_create_file (sb, CHIP,
2083 dev, &dev_init_operations,
2084 &dev->dentry))
2085 goto enomem3;
2086
2087 /* other endpoint files are available after hardware setup,
2088 * from binding to a controller.
2089 */
2090 the_device = dev;
2091 return 0;
2092
2093 enomem3:
2094 put_dev (dev);
2095 enomem2:
2096 dput (d);
2097 enomem1:
2098 iput (inode);
2099 enomem0:
2100 return -ENOMEM;
2101 }
2102
2103 /* "mount -t gadgetfs path /dev/gadget" ends up here */
2104 static int
2105 gadgetfs_get_sb (struct file_system_type *t, int flags,
2106 const char *path, void *opts, struct vfsmount *mnt)
2107 {
2108 return get_sb_single (t, flags, opts, gadgetfs_fill_super, mnt);
2109 }
2110
2111 static void
2112 gadgetfs_kill_sb (struct super_block *sb)
2113 {
2114 kill_litter_super (sb);
2115 if (the_device) {
2116 put_dev (the_device);
2117 the_device = NULL;
2118 }
2119 }
2120
2121 /*----------------------------------------------------------------------*/
2122
2123 static struct file_system_type gadgetfs_type = {
2124 .owner = THIS_MODULE,
2125 .name = shortname,
2126 .get_sb = gadgetfs_get_sb,
2127 .kill_sb = gadgetfs_kill_sb,
2128 };
2129
2130 /*----------------------------------------------------------------------*/
2131
2132 static int __init init (void)
2133 {
2134 int status;
2135
2136 status = register_filesystem (&gadgetfs_type);
2137 if (status == 0)
2138 pr_info ("%s: %s, version " DRIVER_VERSION "\n",
2139 shortname, driver_desc);
2140 return status;
2141 }
2142 module_init (init);
2143
2144 static void __exit cleanup (void)
2145 {
2146 pr_debug ("unregister %s\n", shortname);
2147 unregister_filesystem (&gadgetfs_type);
2148 }
2149 module_exit (cleanup);
2150
Linux 2.6 ibm-acpi/thinkpad-acpi driver git tree