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[PATCH] inode-diet: Eliminate i_blksize from the inode structure
[linux-2.6/libata-dev.git] / drivers / usb / gadget / inode.c
blob2a7162d897994e631a96e49c91751eb968ca705f
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
36 #include <linux/device.h>
37 #include <linux/moduleparam.h>
38
39 #include <linux/usb_gadgetfs.h>
40 #include <linux/usb_gadget.h>
41
42
43 /*
44 * The gadgetfs API maps each endpoint to a file descriptor so that you
45 * can use standard synchronous read/write calls for I/O. There's some
46 * O_NONBLOCK and O_ASYNC/FASYNC style i/o support. Example usermode
47 * drivers show how this works in practice. You can also use AIO to
48 * eliminate I/O gaps between requests, to help when streaming data.
49 *
50 * Key parts that must be USB-specific are protocols defining how the
51 * read/write operations relate to the hardware state machines. There
52 * are two types of files. One type is for the device, implementing ep0.
53 * The other type is for each IN or OUT endpoint. In both cases, the
54 * user mode driver must configure the hardware before using it.
55 *
56 * - First, dev_config() is called when /dev/gadget/$CHIP is configured
57 * (by writing configuration and device descriptors). Afterwards it
58 * may serve as a source of device events, used to handle all control
59 * requests other than basic enumeration.
60 *
61 * - Then either immediately, or after a SET_CONFIGURATION control request,
62 * ep_config() is called when each /dev/gadget/ep* file is configured
63 * (by writing endpoint descriptors). Afterwards these files are used
64 * to write() IN data or to read() OUT data. To halt the endpoint, a
65 * "wrong direction" request is issued (like reading an IN endpoint).
66 *
67 * Unlike "usbfs" the only ioctl()s are for things that are rare, and maybe
68 * not possible on all hardware. For example, precise fault handling with
69 * respect to data left in endpoint fifos after aborted operations; or
70 * selective clearing of endpoint halts, to implement SET_INTERFACE.
71 */
72
73 #define DRIVER_DESC "USB Gadget filesystem"
74 #define DRIVER_VERSION "24 Aug 2004"
75
76 static const char driver_desc [] = DRIVER_DESC;
77 static const char shortname [] = "gadgetfs";
78
79 MODULE_DESCRIPTION (DRIVER_DESC);
80 MODULE_AUTHOR ("David Brownell");
81 MODULE_LICENSE ("GPL");
82
83
84 /*----------------------------------------------------------------------*/
85
86 #define GADGETFS_MAGIC 0xaee71ee7
87 #define DMA_ADDR_INVALID (~(dma_addr_t)0)
88
89 /* /dev/gadget/$CHIP represents ep0 and the whole device */
90 enum ep0_state {
91 /* DISBLED is the initial state.
92 */
93 STATE_DEV_DISABLED = 0,
94
95 /* Only one open() of /dev/gadget/$CHIP; only one file tracks
96 * ep0/device i/o modes and binding to the controller. Driver
97 * must always write descriptors to initialize the device, then
98 * the device becomes UNCONNECTED until enumeration.
99 */
100 STATE_OPENED,
101
102 /* From then on, ep0 fd is in either of two basic modes:
103 * - (UN)CONNECTED: read usb_gadgetfs_event(s) from it
104 * - SETUP: read/write will transfer control data and succeed;
105 * or if "wrong direction", performs protocol stall
106 */
107 STATE_UNCONNECTED,
108 STATE_CONNECTED,
109 STATE_SETUP,
110
111 /* UNBOUND means the driver closed ep0, so the device won't be
112 * accessible again (DEV_DISABLED) until all fds are closed.
113 */
114 STATE_DEV_UNBOUND,
115 };
116
117 /* enough for the whole queue: most events invalidate others */
118 #define N_EVENT 5
119
120 struct dev_data {
121 spinlock_t lock;
122 atomic_t count;
123 enum ep0_state state;
124 struct usb_gadgetfs_event event [N_EVENT];
125 unsigned ev_next;
126 struct fasync_struct *fasync;
127 u8 current_config;
128
129 /* drivers reading ep0 MUST handle control requests (SETUP)
130 * reported that way; else the host will time out.
131 */
132 unsigned usermode_setup : 1,
133 setup_in : 1,
134 setup_can_stall : 1,
135 setup_out_ready : 1,
136 setup_out_error : 1,
137 setup_abort : 1;
138 unsigned setup_wLength;
139
140 /* the rest is basically write-once */
141 struct usb_config_descriptor *config, *hs_config;
142 struct usb_device_descriptor *dev;
143 struct usb_request *req;
144 struct usb_gadget *gadget;
145 struct list_head epfiles;
146 void *buf;
147 wait_queue_head_t wait;
148 struct super_block *sb;
149 struct dentry *dentry;
150
151 /* except this scratch i/o buffer for ep0 */
152 u8 rbuf [256];
153 };
154
155 static inline void get_dev (struct dev_data *data)
156 {
157 atomic_inc (&data->count);
158 }
159
160 static void put_dev (struct dev_data *data)
161 {
162 if (likely (!atomic_dec_and_test (&data->count)))
163 return;
164 /* needs no more cleanup */
165 BUG_ON (waitqueue_active (&data->wait));
166 kfree (data);
167 }
168
169 static struct dev_data *dev_new (void)
170 {
171 struct dev_data *dev;
172
173 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
174 if (!dev)
175 return NULL;
176 dev->state = STATE_DEV_DISABLED;
177 atomic_set (&dev->count, 1);
178 spin_lock_init (&dev->lock);
179 INIT_LIST_HEAD (&dev->epfiles);
180 init_waitqueue_head (&dev->wait);
181 return dev;
182 }
183
184 /*----------------------------------------------------------------------*/
185
186 /* other /dev/gadget/$ENDPOINT files represent endpoints */
187 enum ep_state {
188 STATE_EP_DISABLED = 0,
189 STATE_EP_READY,
190 STATE_EP_DEFER_ENABLE,
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 BUG_ON (down_trylock (&data->lock) != 0);
226 kfree (data);
227 }
228
229 /*----------------------------------------------------------------------*/
230
231 /* most "how to use the hardware" policy choices are in userspace:
232 * mapping endpoint roles (which the driver needs) to the capabilities
233 * which the usb controller has. most of those capabilities are exposed
234 * implicitly, starting with the driver name and then endpoint names.
235 */
236
237 static const char *CHIP;
238
239 /*----------------------------------------------------------------------*/
240
241 /* NOTE: don't use dev_printk calls before binding to the gadget
242 * at the end of ep0 configuration, or after unbind.
243 */
244
245 /* too wordy: dev_printk(level , &(d)->gadget->dev , fmt , ## args) */
246 #define xprintk(d,level,fmt,args...) \
247 printk(level "%s: " fmt , shortname , ## args)
248
249 #ifdef DEBUG
250 #define DBG(dev,fmt,args...) \
251 xprintk(dev , KERN_DEBUG , fmt , ## args)
252 #else
253 #define DBG(dev,fmt,args...) \
254 do { } while (0)
255 #endif /* DEBUG */
256
257 #ifdef VERBOSE
258 #define VDEBUG DBG
259 #else
260 #define VDEBUG(dev,fmt,args...) \
261 do { } while (0)
262 #endif /* DEBUG */
263
264 #define ERROR(dev,fmt,args...) \
265 xprintk(dev , KERN_ERR , fmt , ## args)
266 #define WARN(dev,fmt,args...) \
267 xprintk(dev , KERN_WARNING , fmt , ## args)
268 #define INFO(dev,fmt,args...) \
269 xprintk(dev , KERN_INFO , fmt , ## args)
270
271
272 /*----------------------------------------------------------------------*/
273
274 /* SYNCHRONOUS ENDPOINT OPERATIONS (bulk/intr/iso)
275 *
276 * After opening, configure non-control endpoints. Then use normal
277 * stream read() and write() requests; and maybe ioctl() to get more
278 * precise FIFO status when recovering from cancellation.
279 */
280
281 static void epio_complete (struct usb_ep *ep, struct usb_request *req)
282 {
283 struct ep_data *epdata = ep->driver_data;
284
285 if (!req->context)
286 return;
287 if (req->status)
288 epdata->status = req->status;
289 else
290 epdata->status = req->actual;
291 complete ((struct completion *)req->context);
292 }
293
294 /* tasklock endpoint, returning when it's connected.
295 * still need dev->lock to use epdata->ep.
296 */
297 static int
298 get_ready_ep (unsigned f_flags, struct ep_data *epdata)
299 {
300 int val;
301
302 if (f_flags & O_NONBLOCK) {
303 if (down_trylock (&epdata->lock) != 0)
304 goto nonblock;
305 if (epdata->state != STATE_EP_ENABLED) {
306 up (&epdata->lock);
307 nonblock:
308 val = -EAGAIN;
309 } else
310 val = 0;
311 return val;
312 }
313
314 if ((val = down_interruptible (&epdata->lock)) < 0)
315 return val;
316 newstate:
317 switch (epdata->state) {
318 case STATE_EP_ENABLED:
319 break;
320 case STATE_EP_DEFER_ENABLE:
321 DBG (epdata->dev, "%s wait for host\n", epdata->name);
322 if ((val = wait_event_interruptible (epdata->wait,
323 epdata->state != STATE_EP_DEFER_ENABLE
324 || epdata->dev->state == STATE_DEV_UNBOUND
325 )) < 0)
326 goto fail;
327 goto newstate;
328 // case STATE_EP_DISABLED: /* "can't happen" */
329 // case STATE_EP_READY: /* "can't happen" */
330 default: /* error! */
331 pr_debug ("%s: ep %p not available, state %d\n",
332 shortname, epdata, epdata->state);
333 // FALLTHROUGH
334 case STATE_EP_UNBOUND: /* clean disconnect */
335 val = -ENODEV;
336 fail:
337 up (&epdata->lock);
338 }
339 return val;
340 }
341
342 static ssize_t
343 ep_io (struct ep_data *epdata, void *buf, unsigned len)
344 {
345 DECLARE_COMPLETION (done);
346 int value;
347
348 spin_lock_irq (&epdata->dev->lock);
349 if (likely (epdata->ep != NULL)) {
350 struct usb_request *req = epdata->req;
351
352 req->context = &done;
353 req->complete = epio_complete;
354 req->buf = buf;
355 req->length = len;
356 value = usb_ep_queue (epdata->ep, req, GFP_ATOMIC);
357 } else
358 value = -ENODEV;
359 spin_unlock_irq (&epdata->dev->lock);
360
361 if (likely (value == 0)) {
362 value = wait_event_interruptible (done.wait, done.done);
363 if (value != 0) {
364 spin_lock_irq (&epdata->dev->lock);
365 if (likely (epdata->ep != NULL)) {
366 DBG (epdata->dev, "%s i/o interrupted\n",
367 epdata->name);
368 usb_ep_dequeue (epdata->ep, epdata->req);
369 spin_unlock_irq (&epdata->dev->lock);
370
371 wait_event (done.wait, done.done);
372 if (epdata->status == -ECONNRESET)
373 epdata->status = -EINTR;
374 } else {
375 spin_unlock_irq (&epdata->dev->lock);
376
377 DBG (epdata->dev, "endpoint gone\n");
378 epdata->status = -ENODEV;
379 }
380 }
381 return epdata->status;
382 }
383 return value;
384 }
385
386
387 /* handle a synchronous OUT bulk/intr/iso transfer */
388 static ssize_t
389 ep_read (struct file *fd, char __user *buf, size_t len, loff_t *ptr)
390 {
391 struct ep_data *data = fd->private_data;
392 void *kbuf;
393 ssize_t value;
394
395 if ((value = get_ready_ep (fd->f_flags, data)) < 0)
396 return value;
397
398 /* halt any endpoint by doing a "wrong direction" i/o call */
399 if (data->desc.bEndpointAddress & USB_DIR_IN) {
400 if ((data->desc.bmAttributes & USB_ENDPOINT_XFERTYPE_MASK)
401 == USB_ENDPOINT_XFER_ISOC)
402 return -EINVAL;
403 DBG (data->dev, "%s halt\n", data->name);
404 spin_lock_irq (&data->dev->lock);
405 if (likely (data->ep != NULL))
406 usb_ep_set_halt (data->ep);
407 spin_unlock_irq (&data->dev->lock);
408 up (&data->lock);
409 return -EBADMSG;
410 }
411
412 /* FIXME readahead for O_NONBLOCK and poll(); careful with ZLPs */
413
414 value = -ENOMEM;
415 kbuf = kmalloc (len, SLAB_KERNEL);
416 if (unlikely (!kbuf))
417 goto free1;
418
419 value = ep_io (data, kbuf, len);
420 VDEBUG (data->dev, "%s read %zu OUT, status %d\n",
421 data->name, len, (int) value);
422 if (value >= 0 && copy_to_user (buf, kbuf, value))
423 value = -EFAULT;
424
425 free1:
426 up (&data->lock);
427 kfree (kbuf);
428 return value;
429 }
430
431 /* handle a synchronous IN bulk/intr/iso transfer */
432 static ssize_t
433 ep_write (struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
434 {
435 struct ep_data *data = fd->private_data;
436 void *kbuf;
437 ssize_t value;
438
439 if ((value = get_ready_ep (fd->f_flags, data)) < 0)
440 return value;
441
442 /* halt any endpoint by doing a "wrong direction" i/o call */
443 if (!(data->desc.bEndpointAddress & USB_DIR_IN)) {
444 if ((data->desc.bmAttributes & USB_ENDPOINT_XFERTYPE_MASK)
445 == USB_ENDPOINT_XFER_ISOC)
446 return -EINVAL;
447 DBG (data->dev, "%s halt\n", data->name);
448 spin_lock_irq (&data->dev->lock);
449 if (likely (data->ep != NULL))
450 usb_ep_set_halt (data->ep);
451 spin_unlock_irq (&data->dev->lock);
452 up (&data->lock);
453 return -EBADMSG;
454 }
455
456 /* FIXME writebehind for O_NONBLOCK and poll(), qlen = 1 */
457
458 value = -ENOMEM;
459 kbuf = kmalloc (len, SLAB_KERNEL);
460 if (!kbuf)
461 goto free1;
462 if (copy_from_user (kbuf, buf, len)) {
463 value = -EFAULT;
464 goto free1;
465 }
466
467 value = ep_io (data, kbuf, len);
468 VDEBUG (data->dev, "%s write %zu IN, status %d\n",
469 data->name, len, (int) value);
470 free1:
471 up (&data->lock);
472 kfree (kbuf);
473 return value;
474 }
475
476 static int
477 ep_release (struct inode *inode, struct file *fd)
478 {
479 struct ep_data *data = fd->private_data;
480
481 /* clean up if this can be reopened */
482 if (data->state != STATE_EP_UNBOUND) {
483 data->state = STATE_EP_DISABLED;
484 data->desc.bDescriptorType = 0;
485 data->hs_desc.bDescriptorType = 0;
486 usb_ep_disable(data->ep);
487 }
488 put_ep (data);
489 return 0;
490 }
491
492 static int ep_ioctl (struct inode *inode, struct file *fd,
493 unsigned code, unsigned long value)
494 {
495 struct ep_data *data = fd->private_data;
496 int status;
497
498 if ((status = get_ready_ep (fd->f_flags, data)) < 0)
499 return status;
500
501 spin_lock_irq (&data->dev->lock);
502 if (likely (data->ep != NULL)) {
503 switch (code) {
504 case GADGETFS_FIFO_STATUS:
505 status = usb_ep_fifo_status (data->ep);
506 break;
507 case GADGETFS_FIFO_FLUSH:
508 usb_ep_fifo_flush (data->ep);
509 break;
510 case GADGETFS_CLEAR_HALT:
511 status = usb_ep_clear_halt (data->ep);
512 break;
513 default:
514 status = -ENOTTY;
515 }
516 } else
517 status = -ENODEV;
518 spin_unlock_irq (&data->dev->lock);
519 up (&data->lock);
520 return status;
521 }
522
523 /*----------------------------------------------------------------------*/
524
525 /* ASYNCHRONOUS ENDPOINT I/O OPERATIONS (bulk/intr/iso) */
526
527 struct kiocb_priv {
528 struct usb_request *req;
529 struct ep_data *epdata;
530 void *buf;
531 char __user *ubuf; /* NULL for writes */
532 unsigned actual;
533 };
534
535 static int ep_aio_cancel(struct kiocb *iocb, struct io_event *e)
536 {
537 struct kiocb_priv *priv = iocb->private;
538 struct ep_data *epdata;
539 int value;
540
541 local_irq_disable();
542 epdata = priv->epdata;
543 // spin_lock(&epdata->dev->lock);
544 kiocbSetCancelled(iocb);
545 if (likely(epdata && epdata->ep && priv->req))
546 value = usb_ep_dequeue (epdata->ep, priv->req);
547 else
548 value = -EINVAL;
549 // spin_unlock(&epdata->dev->lock);
550 local_irq_enable();
551
552 aio_put_req(iocb);
553 return value;
554 }
555
556 static ssize_t ep_aio_read_retry(struct kiocb *iocb)
557 {
558 struct kiocb_priv *priv = iocb->private;
559 ssize_t status = priv->actual;
560
561 /* we "retry" to get the right mm context for this: */
562 status = copy_to_user(priv->ubuf, priv->buf, priv->actual);
563 if (unlikely(0 != status))
564 status = -EFAULT;
565 else
566 status = priv->actual;
567 kfree(priv->buf);
568 kfree(priv);
569 return status;
570 }
571
572 static void ep_aio_complete(struct usb_ep *ep, struct usb_request *req)
573 {
574 struct kiocb *iocb = req->context;
575 struct kiocb_priv *priv = iocb->private;
576 struct ep_data *epdata = priv->epdata;
577
578 /* lock against disconnect (and ideally, cancel) */
579 spin_lock(&epdata->dev->lock);
580 priv->req = NULL;
581 priv->epdata = NULL;
582 if (priv->ubuf == NULL
583 || unlikely(req->actual == 0)
584 || unlikely(kiocbIsCancelled(iocb))) {
585 kfree(req->buf);
586 kfree(priv);
587 iocb->private = NULL;
588 /* aio_complete() reports bytes-transferred _and_ faults */
589 if (unlikely(kiocbIsCancelled(iocb)))
590 aio_put_req(iocb);
591 else
592 aio_complete(iocb,
593 req->actual ? req->actual : req->status,
594 req->status);
595 } else {
596 /* retry() won't report both; so we hide some faults */
597 if (unlikely(0 != req->status))
598 DBG(epdata->dev, "%s fault %d len %d\n",
599 ep->name, req->status, req->actual);
600
601 priv->buf = req->buf;
602 priv->actual = req->actual;
603 kick_iocb(iocb);
604 }
605 spin_unlock(&epdata->dev->lock);
606
607 usb_ep_free_request(ep, req);
608 put_ep(epdata);
609 }
610
611 static ssize_t
612 ep_aio_rwtail(
613 struct kiocb *iocb,
614 char *buf,
615 size_t len,
616 struct ep_data *epdata,
617 char __user *ubuf
618 )
619 {
620 struct kiocb_priv *priv;
621 struct usb_request *req;
622 ssize_t value;
623
624 priv = kmalloc(sizeof *priv, GFP_KERNEL);
625 if (!priv) {
626 value = -ENOMEM;
627 fail:
628 kfree(buf);
629 return value;
630 }
631 iocb->private = priv;
632 priv->ubuf = ubuf;
633
634 value = get_ready_ep(iocb->ki_filp->f_flags, epdata);
635 if (unlikely(value < 0)) {
636 kfree(priv);
637 goto fail;
638 }
639
640 iocb->ki_cancel = ep_aio_cancel;
641 get_ep(epdata);
642 priv->epdata = epdata;
643 priv->actual = 0;
644
645 /* each kiocb is coupled to one usb_request, but we can't
646 * allocate or submit those if the host disconnected.
647 */
648 spin_lock_irq(&epdata->dev->lock);
649 if (likely(epdata->ep)) {
650 req = usb_ep_alloc_request(epdata->ep, GFP_ATOMIC);
651 if (likely(req)) {
652 priv->req = req;
653 req->buf = buf;
654 req->length = len;
655 req->complete = ep_aio_complete;
656 req->context = iocb;
657 value = usb_ep_queue(epdata->ep, req, GFP_ATOMIC);
658 if (unlikely(0 != value))
659 usb_ep_free_request(epdata->ep, req);
660 } else
661 value = -EAGAIN;
662 } else
663 value = -ENODEV;
664 spin_unlock_irq(&epdata->dev->lock);
665
666 up(&epdata->lock);
667
668 if (unlikely(value)) {
669 kfree(priv);
670 put_ep(epdata);
671 } else
672 value = (ubuf ? -EIOCBRETRY : -EIOCBQUEUED);
673 return value;
674 }
675
676 static ssize_t
677 ep_aio_read(struct kiocb *iocb, char __user *ubuf, size_t len, loff_t o)
678 {
679 struct ep_data *epdata = iocb->ki_filp->private_data;
680 char *buf;
681
682 if (unlikely(epdata->desc.bEndpointAddress & USB_DIR_IN))
683 return -EINVAL;
684 buf = kmalloc(len, GFP_KERNEL);
685 if (unlikely(!buf))
686 return -ENOMEM;
687 iocb->ki_retry = ep_aio_read_retry;
688 return ep_aio_rwtail(iocb, buf, len, epdata, ubuf);
689 }
690
691 static ssize_t
692 ep_aio_write(struct kiocb *iocb, const char __user *ubuf, size_t len, loff_t o)
693 {
694 struct ep_data *epdata = iocb->ki_filp->private_data;
695 char *buf;
696
697 if (unlikely(!(epdata->desc.bEndpointAddress & USB_DIR_IN)))
698 return -EINVAL;
699 buf = kmalloc(len, GFP_KERNEL);
700 if (unlikely(!buf))
701 return -ENOMEM;
702 if (unlikely(copy_from_user(buf, ubuf, len) != 0)) {
703 kfree(buf);
704 return -EFAULT;
705 }
706 return ep_aio_rwtail(iocb, buf, len, epdata, NULL);
707 }
708
709 /*----------------------------------------------------------------------*/
710
711 /* used after endpoint configuration */
712 static struct file_operations ep_io_operations = {
713 .owner = THIS_MODULE,
714 .llseek = no_llseek,
715
716 .read = ep_read,
717 .write = ep_write,
718 .ioctl = ep_ioctl,
719 .release = ep_release,
720
721 .aio_read = ep_aio_read,
722 .aio_write = ep_aio_write,
723 };
724
725 /* ENDPOINT INITIALIZATION
726 *
727 * fd = open ("/dev/gadget/$ENDPOINT", O_RDWR)
728 * status = write (fd, descriptors, sizeof descriptors)
729 *
730 * That write establishes the endpoint configuration, configuring
731 * the controller to process bulk, interrupt, or isochronous transfers
732 * at the right maxpacket size, and so on.
733 *
734 * The descriptors are message type 1, identified by a host order u32
735 * at the beginning of what's written. Descriptor order is: full/low
736 * speed descriptor, then optional high speed descriptor.
737 */
738 static ssize_t
739 ep_config (struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
740 {
741 struct ep_data *data = fd->private_data;
742 struct usb_ep *ep;
743 u32 tag;
744 int value;
745
746 if ((value = down_interruptible (&data->lock)) < 0)
747 return value;
748
749 if (data->state != STATE_EP_READY) {
750 value = -EL2HLT;
751 goto fail;
752 }
753
754 value = len;
755 if (len < USB_DT_ENDPOINT_SIZE + 4)
756 goto fail0;
757
758 /* we might need to change message format someday */
759 if (copy_from_user (&tag, buf, 4)) {
760 goto fail1;
761 }
762 if (tag != 1) {
763 DBG(data->dev, "config %s, bad tag %d\n", data->name, tag);
764 goto fail0;
765 }
766 buf += 4;
767 len -= 4;
768
769 /* NOTE: audio endpoint extensions not accepted here;
770 * just don't include the extra bytes.
771 */
772
773 /* full/low speed descriptor, then high speed */
774 if (copy_from_user (&data->desc, buf, USB_DT_ENDPOINT_SIZE)) {
775 goto fail1;
776 }
777 if (data->desc.bLength != USB_DT_ENDPOINT_SIZE
778 || data->desc.bDescriptorType != USB_DT_ENDPOINT)
779 goto fail0;
780 if (len != USB_DT_ENDPOINT_SIZE) {
781 if (len != 2 * USB_DT_ENDPOINT_SIZE)
782 goto fail0;
783 if (copy_from_user (&data->hs_desc, buf + USB_DT_ENDPOINT_SIZE,
784 USB_DT_ENDPOINT_SIZE)) {
785 goto fail1;
786 }
787 if (data->hs_desc.bLength != USB_DT_ENDPOINT_SIZE
788 || data->hs_desc.bDescriptorType
789 != USB_DT_ENDPOINT) {
790 DBG(data->dev, "config %s, bad hs length or type\n",
791 data->name);
792 goto fail0;
793 }
794 }
795 value = len;
796
797 spin_lock_irq (&data->dev->lock);
798 if (data->dev->state == STATE_DEV_UNBOUND) {
799 value = -ENOENT;
800 goto gone;
801 } else if ((ep = data->ep) == NULL) {
802 value = -ENODEV;
803 goto gone;
804 }
805 switch (data->dev->gadget->speed) {
806 case USB_SPEED_LOW:
807 case USB_SPEED_FULL:
808 value = usb_ep_enable (ep, &data->desc);
809 if (value == 0)
810 data->state = STATE_EP_ENABLED;
811 break;
812 #ifdef CONFIG_USB_GADGET_DUALSPEED
813 case USB_SPEED_HIGH:
814 /* fails if caller didn't provide that descriptor... */
815 value = usb_ep_enable (ep, &data->hs_desc);
816 if (value == 0)
817 data->state = STATE_EP_ENABLED;
818 break;
819 #endif
820 default:
821 DBG (data->dev, "unconnected, %s init deferred\n",
822 data->name);
823 data->state = STATE_EP_DEFER_ENABLE;
824 }
825 if (value == 0)
826 fd->f_op = &ep_io_operations;
827 gone:
828 spin_unlock_irq (&data->dev->lock);
829 if (value < 0) {
830 fail:
831 data->desc.bDescriptorType = 0;
832 data->hs_desc.bDescriptorType = 0;
833 }
834 up (&data->lock);
835 return value;
836 fail0:
837 value = -EINVAL;
838 goto fail;
839 fail1:
840 value = -EFAULT;
841 goto fail;
842 }
843
844 static int
845 ep_open (struct inode *inode, struct file *fd)
846 {
847 struct ep_data *data = inode->i_private;
848 int value = -EBUSY;
849
850 if (down_interruptible (&data->lock) != 0)
851 return -EINTR;
852 spin_lock_irq (&data->dev->lock);
853 if (data->dev->state == STATE_DEV_UNBOUND)
854 value = -ENOENT;
855 else if (data->state == STATE_EP_DISABLED) {
856 value = 0;
857 data->state = STATE_EP_READY;
858 get_ep (data);
859 fd->private_data = data;
860 VDEBUG (data->dev, "%s ready\n", data->name);
861 } else
862 DBG (data->dev, "%s state %d\n",
863 data->name, data->state);
864 spin_unlock_irq (&data->dev->lock);
865 up (&data->lock);
866 return value;
867 }
868
869 /* used before endpoint configuration */
870 static struct file_operations ep_config_operations = {
871 .owner = THIS_MODULE,
872 .llseek = no_llseek,
873
874 .open = ep_open,
875 .write = ep_config,
876 .release = ep_release,
877 };
878
879 /*----------------------------------------------------------------------*/
880
881 /* EP0 IMPLEMENTATION can be partly in userspace.
882 *
883 * Drivers that use this facility receive various events, including
884 * control requests the kernel doesn't handle. Drivers that don't
885 * use this facility may be too simple-minded for real applications.
886 */
887
888 static inline void ep0_readable (struct dev_data *dev)
889 {
890 wake_up (&dev->wait);
891 kill_fasync (&dev->fasync, SIGIO, POLL_IN);
892 }
893
894 static void clean_req (struct usb_ep *ep, struct usb_request *req)
895 {
896 struct dev_data *dev = ep->driver_data;
897
898 if (req->buf != dev->rbuf) {
899 usb_ep_free_buffer (ep, req->buf, req->dma, req->length);
900 req->buf = dev->rbuf;
901 req->dma = DMA_ADDR_INVALID;
902 }
903 req->complete = epio_complete;
904 dev->setup_out_ready = 0;
905 }
906
907 static void ep0_complete (struct usb_ep *ep, struct usb_request *req)
908 {
909 struct dev_data *dev = ep->driver_data;
910 int free = 1;
911
912 /* for control OUT, data must still get to userspace */
913 if (!dev->setup_in) {
914 dev->setup_out_error = (req->status != 0);
915 if (!dev->setup_out_error)
916 free = 0;
917 dev->setup_out_ready = 1;
918 ep0_readable (dev);
919 } else if (dev->state == STATE_SETUP)
920 dev->state = STATE_CONNECTED;
921
922 /* clean up as appropriate */
923 if (free && req->buf != &dev->rbuf)
924 clean_req (ep, req);
925 req->complete = epio_complete;
926 }
927
928 static int setup_req (struct usb_ep *ep, struct usb_request *req, u16 len)
929 {
930 struct dev_data *dev = ep->driver_data;
931
932 if (dev->setup_out_ready) {
933 DBG (dev, "ep0 request busy!\n");
934 return -EBUSY;
935 }
936 if (len > sizeof (dev->rbuf))
937 req->buf = usb_ep_alloc_buffer (ep, len, &req->dma, GFP_ATOMIC);
938 if (req->buf == 0) {
939 req->buf = dev->rbuf;
940 return -ENOMEM;
941 }
942 req->complete = ep0_complete;
943 req->length = len;
944 req->zero = 0;
945 return 0;
946 }
947
948 static ssize_t
949 ep0_read (struct file *fd, char __user *buf, size_t len, loff_t *ptr)
950 {
951 struct dev_data *dev = fd->private_data;
952 ssize_t retval;
953 enum ep0_state state;
954
955 spin_lock_irq (&dev->lock);
956
957 /* report fd mode change before acting on it */
958 if (dev->setup_abort) {
959 dev->setup_abort = 0;
960 retval = -EIDRM;
961 goto done;
962 }
963
964 /* control DATA stage */
965 if ((state = dev->state) == STATE_SETUP) {
966
967 if (dev->setup_in) { /* stall IN */
968 VDEBUG(dev, "ep0in stall\n");
969 (void) usb_ep_set_halt (dev->gadget->ep0);
970 retval = -EL2HLT;
971 dev->state = STATE_CONNECTED;
972
973 } else if (len == 0) { /* ack SET_CONFIGURATION etc */
974 struct usb_ep *ep = dev->gadget->ep0;
975 struct usb_request *req = dev->req;
976
977 if ((retval = setup_req (ep, req, 0)) == 0)
978 retval = usb_ep_queue (ep, req, GFP_ATOMIC);
979 dev->state = STATE_CONNECTED;
980
981 /* assume that was SET_CONFIGURATION */
982 if (dev->current_config) {
983 unsigned power;
984 #ifdef CONFIG_USB_GADGET_DUALSPEED
985 if (dev->gadget->speed == USB_SPEED_HIGH)
986 power = dev->hs_config->bMaxPower;
987 else
988 #endif
989 power = dev->config->bMaxPower;
990 usb_gadget_vbus_draw(dev->gadget, 2 * power);
991 }
992
993 } else { /* collect OUT data */
994 if ((fd->f_flags & O_NONBLOCK) != 0
995 && !dev->setup_out_ready) {
996 retval = -EAGAIN;
997 goto done;
998 }
999 spin_unlock_irq (&dev->lock);
1000 retval = wait_event_interruptible (dev->wait,
1001 dev->setup_out_ready != 0);
1002
1003 /* FIXME state could change from under us */
1004 spin_lock_irq (&dev->lock);
1005 if (retval)
1006 goto done;
1007 if (dev->setup_out_error)
1008 retval = -EIO;
1009 else {
1010 len = min (len, (size_t)dev->req->actual);
1011 // FIXME don't call this with the spinlock held ...
1012 if (copy_to_user (buf, &dev->req->buf, len))
1013 retval = -EFAULT;
1014 clean_req (dev->gadget->ep0, dev->req);
1015 /* NOTE userspace can't yet choose to stall */
1016 }
1017 }
1018 goto done;
1019 }
1020
1021 /* else normal: return event data */
1022 if (len < sizeof dev->event [0]) {
1023 retval = -EINVAL;
1024 goto done;
1025 }
1026 len -= len % sizeof (struct usb_gadgetfs_event);
1027 dev->usermode_setup = 1;
1028
1029 scan:
1030 /* return queued events right away */
1031 if (dev->ev_next != 0) {
1032 unsigned i, n;
1033 int tmp = dev->ev_next;
1034
1035 len = min (len, tmp * sizeof (struct usb_gadgetfs_event));
1036 n = len / sizeof (struct usb_gadgetfs_event);
1037
1038 /* ep0 can't deliver events when STATE_SETUP */
1039 for (i = 0; i < n; i++) {
1040 if (dev->event [i].type == GADGETFS_SETUP) {
1041 len = i + 1;
1042 len *= sizeof (struct usb_gadgetfs_event);
1043 n = 0;
1044 break;
1045 }
1046 }
1047 spin_unlock_irq (&dev->lock);
1048 if (copy_to_user (buf, &dev->event, len))
1049 retval = -EFAULT;
1050 else
1051 retval = len;
1052 if (len > 0) {
1053 len /= sizeof (struct usb_gadgetfs_event);
1054
1055 /* NOTE this doesn't guard against broken drivers;
1056 * concurrent ep0 readers may lose events.
1057 */
1058 spin_lock_irq (&dev->lock);
1059 dev->ev_next -= len;
1060 if (dev->ev_next != 0)
1061 memmove (&dev->event, &dev->event [len],
1062 sizeof (struct usb_gadgetfs_event)
1063 * (tmp - len));
1064 if (n == 0)
1065 dev->state = STATE_SETUP;
1066 spin_unlock_irq (&dev->lock);
1067 }
1068 return retval;
1069 }
1070 if (fd->f_flags & O_NONBLOCK) {
1071 retval = -EAGAIN;
1072 goto done;
1073 }
1074
1075 switch (state) {
1076 default:
1077 DBG (dev, "fail %s, state %d\n", __FUNCTION__, state);
1078 retval = -ESRCH;
1079 break;
1080 case STATE_UNCONNECTED:
1081 case STATE_CONNECTED:
1082 spin_unlock_irq (&dev->lock);
1083 DBG (dev, "%s wait\n", __FUNCTION__);
1084
1085 /* wait for events */
1086 retval = wait_event_interruptible (dev->wait,
1087 dev->ev_next != 0);
1088 if (retval < 0)
1089 return retval;
1090 spin_lock_irq (&dev->lock);
1091 goto scan;
1092 }
1093
1094 done:
1095 spin_unlock_irq (&dev->lock);
1096 return retval;
1097 }
1098
1099 static struct usb_gadgetfs_event *
1100 next_event (struct dev_data *dev, enum usb_gadgetfs_event_type type)
1101 {
1102 struct usb_gadgetfs_event *event;
1103 unsigned i;
1104
1105 switch (type) {
1106 /* these events purge the queue */
1107 case GADGETFS_DISCONNECT:
1108 if (dev->state == STATE_SETUP)
1109 dev->setup_abort = 1;
1110 // FALL THROUGH
1111 case GADGETFS_CONNECT:
1112 dev->ev_next = 0;
1113 break;
1114 case GADGETFS_SETUP: /* previous request timed out */
1115 case GADGETFS_SUSPEND: /* same effect */
1116 /* these events can't be repeated */
1117 for (i = 0; i != dev->ev_next; i++) {
1118 if (dev->event [i].type != type)
1119 continue;
1120 DBG (dev, "discard old event %d\n", type);
1121 dev->ev_next--;
1122 if (i == dev->ev_next)
1123 break;
1124 /* indices start at zero, for simplicity */
1125 memmove (&dev->event [i], &dev->event [i + 1],
1126 sizeof (struct usb_gadgetfs_event)
1127 * (dev->ev_next - i));
1128 }
1129 break;
1130 default:
1131 BUG ();
1132 }
1133 event = &dev->event [dev->ev_next++];
1134 BUG_ON (dev->ev_next > N_EVENT);
1135 VDEBUG (dev, "ev %d, next %d\n", type, dev->ev_next);
1136 memset (event, 0, sizeof *event);
1137 event->type = type;
1138 return event;
1139 }
1140
1141 static ssize_t
1142 ep0_write (struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
1143 {
1144 struct dev_data *dev = fd->private_data;
1145 ssize_t retval = -ESRCH;
1146
1147 spin_lock_irq (&dev->lock);
1148
1149 /* report fd mode change before acting on it */
1150 if (dev->setup_abort) {
1151 dev->setup_abort = 0;
1152 retval = -EIDRM;
1153
1154 /* data and/or status stage for control request */
1155 } else if (dev->state == STATE_SETUP) {
1156
1157 /* IN DATA+STATUS caller makes len <= wLength */
1158 if (dev->setup_in) {
1159 retval = setup_req (dev->gadget->ep0, dev->req, len);
1160 if (retval == 0) {
1161 spin_unlock_irq (&dev->lock);
1162 if (copy_from_user (dev->req->buf, buf, len))
1163 retval = -EFAULT;
1164 else {
1165 if (len < dev->setup_wLength)
1166 dev->req->zero = 1;
1167 retval = usb_ep_queue (
1168 dev->gadget->ep0, dev->req,
1169 GFP_KERNEL);
1170 }
1171 if (retval < 0) {
1172 spin_lock_irq (&dev->lock);
1173 clean_req (dev->gadget->ep0, dev->req);
1174 spin_unlock_irq (&dev->lock);
1175 } else
1176 retval = len;
1177
1178 return retval;
1179 }
1180
1181 /* can stall some OUT transfers */
1182 } else if (dev->setup_can_stall) {
1183 VDEBUG(dev, "ep0out stall\n");
1184 (void) usb_ep_set_halt (dev->gadget->ep0);
1185 retval = -EL2HLT;
1186 dev->state = STATE_CONNECTED;
1187 } else {
1188 DBG(dev, "bogus ep0out stall!\n");
1189 }
1190 } else
1191 DBG (dev, "fail %s, state %d\n", __FUNCTION__, dev->state);
1192
1193 spin_unlock_irq (&dev->lock);
1194 return retval;
1195 }
1196
1197 static int
1198 ep0_fasync (int f, struct file *fd, int on)
1199 {
1200 struct dev_data *dev = fd->private_data;
1201 // caller must F_SETOWN before signal delivery happens
1202 VDEBUG (dev, "%s %s\n", __FUNCTION__, on ? "on" : "off");
1203 return fasync_helper (f, fd, on, &dev->fasync);
1204 }
1205
1206 static struct usb_gadget_driver gadgetfs_driver;
1207
1208 static int
1209 dev_release (struct inode *inode, struct file *fd)
1210 {
1211 struct dev_data *dev = fd->private_data;
1212
1213 /* closing ep0 === shutdown all */
1214
1215 usb_gadget_unregister_driver (&gadgetfs_driver);
1216
1217 /* at this point "good" hardware has disconnected the
1218 * device from USB; the host won't see it any more.
1219 * alternatively, all host requests will time out.
1220 */
1221
1222 fasync_helper (-1, fd, 0, &dev->fasync);
1223 kfree (dev->buf);
1224 dev->buf = NULL;
1225 put_dev (dev);
1226
1227 /* other endpoints were all decoupled from this device */
1228 dev->state = STATE_DEV_DISABLED;
1229 return 0;
1230 }
1231
1232 static int dev_ioctl (struct inode *inode, struct file *fd,
1233 unsigned code, unsigned long value)
1234 {
1235 struct dev_data *dev = fd->private_data;
1236 struct usb_gadget *gadget = dev->gadget;
1237
1238 if (gadget->ops->ioctl)
1239 return gadget->ops->ioctl (gadget, code, value);
1240 return -ENOTTY;
1241 }
1242
1243 /* used after device configuration */
1244 static struct file_operations ep0_io_operations = {
1245 .owner = THIS_MODULE,
1246 .llseek = no_llseek,
1247
1248 .read = ep0_read,
1249 .write = ep0_write,
1250 .fasync = ep0_fasync,
1251 // .poll = ep0_poll,
1252 .ioctl = dev_ioctl,
1253 .release = dev_release,
1254 };
1255
1256 /*----------------------------------------------------------------------*/
1257
1258 /* The in-kernel gadget driver handles most ep0 issues, in particular
1259 * enumerating the single configuration (as provided from user space).
1260 *
1261 * Unrecognized ep0 requests may be handled in user space.
1262 */
1263
1264 #ifdef CONFIG_USB_GADGET_DUALSPEED
1265 static void make_qualifier (struct dev_data *dev)
1266 {
1267 struct usb_qualifier_descriptor qual;
1268 struct usb_device_descriptor *desc;
1269
1270 qual.bLength = sizeof qual;
1271 qual.bDescriptorType = USB_DT_DEVICE_QUALIFIER;
1272 qual.bcdUSB = __constant_cpu_to_le16 (0x0200);
1273
1274 desc = dev->dev;
1275 qual.bDeviceClass = desc->bDeviceClass;
1276 qual.bDeviceSubClass = desc->bDeviceSubClass;
1277 qual.bDeviceProtocol = desc->bDeviceProtocol;
1278
1279 /* assumes ep0 uses the same value for both speeds ... */
1280 qual.bMaxPacketSize0 = desc->bMaxPacketSize0;
1281
1282 qual.bNumConfigurations = 1;
1283 qual.bRESERVED = 0;
1284
1285 memcpy (dev->rbuf, &qual, sizeof qual);
1286 }
1287 #endif
1288
1289 static int
1290 config_buf (struct dev_data *dev, u8 type, unsigned index)
1291 {
1292 int len;
1293 #ifdef CONFIG_USB_GADGET_DUALSPEED
1294 int hs;
1295 #endif
1296
1297 /* only one configuration */
1298 if (index > 0)
1299 return -EINVAL;
1300
1301 #ifdef CONFIG_USB_GADGET_DUALSPEED
1302 hs = (dev->gadget->speed == USB_SPEED_HIGH);
1303 if (type == USB_DT_OTHER_SPEED_CONFIG)
1304 hs = !hs;
1305 if (hs) {
1306 dev->req->buf = dev->hs_config;
1307 len = le16_to_cpup (&dev->hs_config->wTotalLength);
1308 } else
1309 #endif
1310 {
1311 dev->req->buf = dev->config;
1312 len = le16_to_cpup (&dev->config->wTotalLength);
1313 }
1314 ((u8 *)dev->req->buf) [1] = type;
1315 return len;
1316 }
1317
1318 static int
1319 gadgetfs_setup (struct usb_gadget *gadget, const struct usb_ctrlrequest *ctrl)
1320 {
1321 struct dev_data *dev = get_gadget_data (gadget);
1322 struct usb_request *req = dev->req;
1323 int value = -EOPNOTSUPP;
1324 struct usb_gadgetfs_event *event;
1325 u16 w_value = le16_to_cpu(ctrl->wValue);
1326 u16 w_length = le16_to_cpu(ctrl->wLength);
1327
1328 spin_lock (&dev->lock);
1329 dev->setup_abort = 0;
1330 if (dev->state == STATE_UNCONNECTED) {
1331 struct usb_ep *ep;
1332 struct ep_data *data;
1333
1334 dev->state = STATE_CONNECTED;
1335 dev->dev->bMaxPacketSize0 = gadget->ep0->maxpacket;
1336
1337 #ifdef CONFIG_USB_GADGET_DUALSPEED
1338 if (gadget->speed == USB_SPEED_HIGH && dev->hs_config == 0) {
1339 ERROR (dev, "no high speed config??\n");
1340 return -EINVAL;
1341 }
1342 #endif /* CONFIG_USB_GADGET_DUALSPEED */
1343
1344 INFO (dev, "connected\n");
1345 event = next_event (dev, GADGETFS_CONNECT);
1346 event->u.speed = gadget->speed;
1347 ep0_readable (dev);
1348
1349 list_for_each_entry (ep, &gadget->ep_list, ep_list) {
1350 data = ep->driver_data;
1351 /* ... down_trylock (&data->lock) ... */
1352 if (data->state != STATE_EP_DEFER_ENABLE)
1353 continue;
1354 #ifdef CONFIG_USB_GADGET_DUALSPEED
1355 if (gadget->speed == USB_SPEED_HIGH)
1356 value = usb_ep_enable (ep, &data->hs_desc);
1357 else
1358 #endif /* CONFIG_USB_GADGET_DUALSPEED */
1359 value = usb_ep_enable (ep, &data->desc);
1360 if (value) {
1361 ERROR (dev, "deferred %s enable --> %d\n",
1362 data->name, value);
1363 continue;
1364 }
1365 data->state = STATE_EP_ENABLED;
1366 wake_up (&data->wait);
1367 DBG (dev, "woke up %s waiters\n", data->name);
1368 }
1369
1370 /* host may have given up waiting for response. we can miss control
1371 * requests handled lower down (device/endpoint status and features);
1372 * then ep0_{read,write} will report the wrong status. controller
1373 * driver will have aborted pending i/o.
1374 */
1375 } else if (dev->state == STATE_SETUP)
1376 dev->setup_abort = 1;
1377
1378 req->buf = dev->rbuf;
1379 req->dma = DMA_ADDR_INVALID;
1380 req->context = NULL;
1381 value = -EOPNOTSUPP;
1382 switch (ctrl->bRequest) {
1383
1384 case USB_REQ_GET_DESCRIPTOR:
1385 if (ctrl->bRequestType != USB_DIR_IN)
1386 goto unrecognized;
1387 switch (w_value >> 8) {
1388
1389 case USB_DT_DEVICE:
1390 value = min (w_length, (u16) sizeof *dev->dev);
1391 req->buf = dev->dev;
1392 break;
1393 #ifdef CONFIG_USB_GADGET_DUALSPEED
1394 case USB_DT_DEVICE_QUALIFIER:
1395 if (!dev->hs_config)
1396 break;
1397 value = min (w_length, (u16)
1398 sizeof (struct usb_qualifier_descriptor));
1399 make_qualifier (dev);
1400 break;
1401 case USB_DT_OTHER_SPEED_CONFIG:
1402 // FALLTHROUGH
1403 #endif
1404 case USB_DT_CONFIG:
1405 value = config_buf (dev,
1406 w_value >> 8,
1407 w_value & 0xff);
1408 if (value >= 0)
1409 value = min (w_length, (u16) value);
1410 break;
1411 case USB_DT_STRING:
1412 goto unrecognized;
1413
1414 default: // all others are errors
1415 break;
1416 }
1417 break;
1418
1419 /* currently one config, two speeds */
1420 case USB_REQ_SET_CONFIGURATION:
1421 if (ctrl->bRequestType != 0)
1422 break;
1423 if (0 == (u8) w_value) {
1424 value = 0;
1425 dev->current_config = 0;
1426 usb_gadget_vbus_draw(gadget, 8 /* mA */ );
1427 // user mode expected to disable endpoints
1428 } else {
1429 u8 config, power;
1430 #ifdef CONFIG_USB_GADGET_DUALSPEED
1431 if (gadget->speed == USB_SPEED_HIGH) {
1432 config = dev->hs_config->bConfigurationValue;
1433 power = dev->hs_config->bMaxPower;
1434 } else
1435 #endif
1436 {
1437 config = dev->config->bConfigurationValue;
1438 power = dev->config->bMaxPower;
1439 }
1440
1441 if (config == (u8) w_value) {
1442 value = 0;
1443 dev->current_config = config;
1444 usb_gadget_vbus_draw(gadget, 2 * power);
1445 }
1446 }
1447
1448 /* report SET_CONFIGURATION like any other control request,
1449 * except that usermode may not stall this. the next
1450 * request mustn't be allowed start until this finishes:
1451 * endpoints and threads set up, etc.
1452 *
1453 * NOTE: older PXA hardware (before PXA 255: without UDCCFR)
1454 * has bad/racey automagic that prevents synchronizing here.
1455 * even kernel mode drivers often miss them.
1456 */
1457 if (value == 0) {
1458 INFO (dev, "configuration #%d\n", dev->current_config);
1459 if (dev->usermode_setup) {
1460 dev->setup_can_stall = 0;
1461 goto delegate;
1462 }
1463 }
1464 break;
1465
1466 #ifndef CONFIG_USB_GADGETFS_PXA2XX
1467 /* PXA automagically handles this request too */
1468 case USB_REQ_GET_CONFIGURATION:
1469 if (ctrl->bRequestType != 0x80)
1470 break;
1471 *(u8 *)req->buf = dev->current_config;
1472 value = min (w_length, (u16) 1);
1473 break;
1474 #endif
1475
1476 default:
1477 unrecognized:
1478 VDEBUG (dev, "%s req%02x.%02x v%04x i%04x l%d\n",
1479 dev->usermode_setup ? "delegate" : "fail",
1480 ctrl->bRequestType, ctrl->bRequest,
1481 w_value, le16_to_cpu(ctrl->wIndex), w_length);
1482
1483 /* if there's an ep0 reader, don't stall */
1484 if (dev->usermode_setup) {
1485 dev->setup_can_stall = 1;
1486 delegate:
1487 dev->setup_in = (ctrl->bRequestType & USB_DIR_IN)
1488 ? 1 : 0;
1489 dev->setup_wLength = w_length;
1490 dev->setup_out_ready = 0;
1491 dev->setup_out_error = 0;
1492 value = 0;
1493
1494 /* read DATA stage for OUT right away */
1495 if (unlikely (!dev->setup_in && w_length)) {
1496 value = setup_req (gadget->ep0, dev->req,
1497 w_length);
1498 if (value < 0)
1499 break;
1500 value = usb_ep_queue (gadget->ep0, dev->req,
1501 GFP_ATOMIC);
1502 if (value < 0) {
1503 clean_req (gadget->ep0, dev->req);
1504 break;
1505 }
1506
1507 /* we can't currently stall these */
1508 dev->setup_can_stall = 0;
1509 }
1510
1511 /* state changes when reader collects event */
1512 event = next_event (dev, GADGETFS_SETUP);
1513 event->u.setup = *ctrl;
1514 ep0_readable (dev);
1515 spin_unlock (&dev->lock);
1516 return 0;
1517 }
1518 }
1519
1520 /* proceed with data transfer and status phases? */
1521 if (value >= 0 && dev->state != STATE_SETUP) {
1522 req->length = value;
1523 req->zero = value < w_length;
1524 value = usb_ep_queue (gadget->ep0, req, GFP_ATOMIC);
1525 if (value < 0) {
1526 DBG (dev, "ep_queue --> %d\n", value);
1527 req->status = 0;
1528 }
1529 }
1530
1531 /* device stalls when value < 0 */
1532 spin_unlock (&dev->lock);
1533 return value;
1534 }
1535
1536 static void destroy_ep_files (struct dev_data *dev)
1537 {
1538 struct list_head *entry, *tmp;
1539
1540 DBG (dev, "%s %d\n", __FUNCTION__, dev->state);
1541
1542 /* dev->state must prevent interference */
1543 restart:
1544 spin_lock_irq (&dev->lock);
1545 list_for_each_safe (entry, tmp, &dev->epfiles) {
1546 struct ep_data *ep;
1547 struct inode *parent;
1548 struct dentry *dentry;
1549
1550 /* break link to FS */
1551 ep = list_entry (entry, struct ep_data, epfiles);
1552 list_del_init (&ep->epfiles);
1553 dentry = ep->dentry;
1554 ep->dentry = NULL;
1555 parent = dentry->d_parent->d_inode;
1556
1557 /* break link to controller */
1558 if (ep->state == STATE_EP_ENABLED)
1559 (void) usb_ep_disable (ep->ep);
1560 ep->state = STATE_EP_UNBOUND;
1561 usb_ep_free_request (ep->ep, ep->req);
1562 ep->ep = NULL;
1563 wake_up (&ep->wait);
1564 put_ep (ep);
1565
1566 spin_unlock_irq (&dev->lock);
1567
1568 /* break link to dcache */
1569 mutex_lock (&parent->i_mutex);
1570 d_delete (dentry);
1571 dput (dentry);
1572 mutex_unlock (&parent->i_mutex);
1573
1574 /* fds may still be open */
1575 goto restart;
1576 }
1577 spin_unlock_irq (&dev->lock);
1578 }
1579
1580
1581 static struct inode *
1582 gadgetfs_create_file (struct super_block *sb, char const *name,
1583 void *data, const struct file_operations *fops,
1584 struct dentry **dentry_p);
1585
1586 static int activate_ep_files (struct dev_data *dev)
1587 {
1588 struct usb_ep *ep;
1589 struct ep_data *data;
1590
1591 gadget_for_each_ep (ep, dev->gadget) {
1592
1593 data = kzalloc(sizeof(*data), GFP_KERNEL);
1594 if (!data)
1595 goto enomem0;
1596 data->state = STATE_EP_DISABLED;
1597 init_MUTEX (&data->lock);
1598 init_waitqueue_head (&data->wait);
1599
1600 strncpy (data->name, ep->name, sizeof (data->name) - 1);
1601 atomic_set (&data->count, 1);
1602 data->dev = dev;
1603 get_dev (dev);
1604
1605 data->ep = ep;
1606 ep->driver_data = data;
1607
1608 data->req = usb_ep_alloc_request (ep, GFP_KERNEL);
1609 if (!data->req)
1610 goto enomem1;
1611
1612 data->inode = gadgetfs_create_file (dev->sb, data->name,
1613 data, &ep_config_operations,
1614 &data->dentry);
1615 if (!data->inode)
1616 goto enomem2;
1617 list_add_tail (&data->epfiles, &dev->epfiles);
1618 }
1619 return 0;
1620
1621 enomem2:
1622 usb_ep_free_request (ep, data->req);
1623 enomem1:
1624 put_dev (dev);
1625 kfree (data);
1626 enomem0:
1627 DBG (dev, "%s enomem\n", __FUNCTION__);
1628 destroy_ep_files (dev);
1629 return -ENOMEM;
1630 }
1631
1632 static void
1633 gadgetfs_unbind (struct usb_gadget *gadget)
1634 {
1635 struct dev_data *dev = get_gadget_data (gadget);
1636
1637 DBG (dev, "%s\n", __FUNCTION__);
1638
1639 spin_lock_irq (&dev->lock);
1640 dev->state = STATE_DEV_UNBOUND;
1641 spin_unlock_irq (&dev->lock);
1642
1643 destroy_ep_files (dev);
1644 gadget->ep0->driver_data = NULL;
1645 set_gadget_data (gadget, NULL);
1646
1647 /* we've already been disconnected ... no i/o is active */
1648 if (dev->req)
1649 usb_ep_free_request (gadget->ep0, dev->req);
1650 DBG (dev, "%s done\n", __FUNCTION__);
1651 put_dev (dev);
1652 }
1653
1654 static struct dev_data *the_device;
1655
1656 static int
1657 gadgetfs_bind (struct usb_gadget *gadget)
1658 {
1659 struct dev_data *dev = the_device;
1660
1661 if (!dev)
1662 return -ESRCH;
1663 if (0 != strcmp (CHIP, gadget->name)) {
1664 printk (KERN_ERR "%s expected %s controller not %s\n",
1665 shortname, CHIP, gadget->name);
1666 return -ENODEV;
1667 }
1668
1669 set_gadget_data (gadget, dev);
1670 dev->gadget = gadget;
1671 gadget->ep0->driver_data = dev;
1672 dev->dev->bMaxPacketSize0 = gadget->ep0->maxpacket;
1673
1674 /* preallocate control response and buffer */
1675 dev->req = usb_ep_alloc_request (gadget->ep0, GFP_KERNEL);
1676 if (!dev->req)
1677 goto enomem;
1678 dev->req->context = NULL;
1679 dev->req->complete = epio_complete;
1680
1681 if (activate_ep_files (dev) < 0)
1682 goto enomem;
1683
1684 INFO (dev, "bound to %s driver\n", gadget->name);
1685 dev->state = STATE_UNCONNECTED;
1686 get_dev (dev);
1687 return 0;
1688
1689 enomem:
1690 gadgetfs_unbind (gadget);
1691 return -ENOMEM;
1692 }
1693
1694 static void
1695 gadgetfs_disconnect (struct usb_gadget *gadget)
1696 {
1697 struct dev_data *dev = get_gadget_data (gadget);
1698
1699 if (dev->state == STATE_UNCONNECTED) {
1700 DBG (dev, "already unconnected\n");
1701 return;
1702 }
1703 dev->state = STATE_UNCONNECTED;
1704
1705 INFO (dev, "disconnected\n");
1706 spin_lock (&dev->lock);
1707 next_event (dev, GADGETFS_DISCONNECT);
1708 ep0_readable (dev);
1709 spin_unlock (&dev->lock);
1710 }
1711
1712 static void
1713 gadgetfs_suspend (struct usb_gadget *gadget)
1714 {
1715 struct dev_data *dev = get_gadget_data (gadget);
1716
1717 INFO (dev, "suspended from state %d\n", dev->state);
1718 spin_lock (&dev->lock);
1719 switch (dev->state) {
1720 case STATE_SETUP: // VERY odd... host died??
1721 case STATE_CONNECTED:
1722 case STATE_UNCONNECTED:
1723 next_event (dev, GADGETFS_SUSPEND);
1724 ep0_readable (dev);
1725 /* FALLTHROUGH */
1726 default:
1727 break;
1728 }
1729 spin_unlock (&dev->lock);
1730 }
1731
1732 static struct usb_gadget_driver gadgetfs_driver = {
1733 #ifdef CONFIG_USB_GADGET_DUALSPEED
1734 .speed = USB_SPEED_HIGH,
1735 #else
1736 .speed = USB_SPEED_FULL,
1737 #endif
1738 .function = (char *) driver_desc,
1739 .bind = gadgetfs_bind,
1740 .unbind = gadgetfs_unbind,
1741 .setup = gadgetfs_setup,
1742 .disconnect = gadgetfs_disconnect,
1743 .suspend = gadgetfs_suspend,
1744
1745 .driver = {
1746 .name = (char *) shortname,
1747 },
1748 };
1749
1750 /*----------------------------------------------------------------------*/
1751
1752 static void gadgetfs_nop(struct usb_gadget *arg) { }
1753
1754 static int gadgetfs_probe (struct usb_gadget *gadget)
1755 {
1756 CHIP = gadget->name;
1757 return -EISNAM;
1758 }
1759
1760 static struct usb_gadget_driver probe_driver = {
1761 .speed = USB_SPEED_HIGH,
1762 .bind = gadgetfs_probe,
1763 .unbind = gadgetfs_nop,
1764 .setup = (void *)gadgetfs_nop,
1765 .disconnect = gadgetfs_nop,
1766 .driver = {
1767 .name = "nop",
1768 },
1769 };
1770
1771
1772 /* DEVICE INITIALIZATION
1773 *
1774 * fd = open ("/dev/gadget/$CHIP", O_RDWR)
1775 * status = write (fd, descriptors, sizeof descriptors)
1776 *
1777 * That write establishes the device configuration, so the kernel can
1778 * bind to the controller ... guaranteeing it can handle enumeration
1779 * at all necessary speeds. Descriptor order is:
1780 *
1781 * . message tag (u32, host order) ... for now, must be zero; it
1782 * would change to support features like multi-config devices
1783 * . full/low speed config ... all wTotalLength bytes (with interface,
1784 * class, altsetting, endpoint, and other descriptors)
1785 * . high speed config ... all descriptors, for high speed operation;
1786 * this one's optional except for high-speed hardware
1787 * . device descriptor
1788 *
1789 * Endpoints are not yet enabled. Drivers may want to immediately
1790 * initialize them, using the /dev/gadget/ep* files that are available
1791 * as soon as the kernel sees the configuration, or they can wait
1792 * until device configuration and interface altsetting changes create
1793 * the need to configure (or unconfigure) them.
1794 *
1795 * After initialization, the device stays active for as long as that
1796 * $CHIP file is open. Events may then be read from that descriptor,
1797 * such as configuration notifications. More complex drivers will handle
1798 * some control requests in user space.
1799 */
1800
1801 static int is_valid_config (struct usb_config_descriptor *config)
1802 {
1803 return config->bDescriptorType == USB_DT_CONFIG
1804 && config->bLength == USB_DT_CONFIG_SIZE
1805 && config->bConfigurationValue != 0
1806 && (config->bmAttributes & USB_CONFIG_ATT_ONE) != 0
1807 && (config->bmAttributes & USB_CONFIG_ATT_WAKEUP) == 0;
1808 /* FIXME if gadget->is_otg, _must_ include an otg descriptor */
1809 /* FIXME check lengths: walk to end */
1810 }
1811
1812 static ssize_t
1813 dev_config (struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
1814 {
1815 struct dev_data *dev = fd->private_data;
1816 ssize_t value = len, length = len;
1817 unsigned total;
1818 u32 tag;
1819 char *kbuf;
1820
1821 if (dev->state != STATE_OPENED)
1822 return -EEXIST;
1823
1824 if (len < (USB_DT_CONFIG_SIZE + USB_DT_DEVICE_SIZE + 4))
1825 return -EINVAL;
1826
1827 /* we might need to change message format someday */
1828 if (copy_from_user (&tag, buf, 4))
1829 return -EFAULT;
1830 if (tag != 0)
1831 return -EINVAL;
1832 buf += 4;
1833 length -= 4;
1834
1835 kbuf = kmalloc (length, SLAB_KERNEL);
1836 if (!kbuf)
1837 return -ENOMEM;
1838 if (copy_from_user (kbuf, buf, length)) {
1839 kfree (kbuf);
1840 return -EFAULT;
1841 }
1842
1843 spin_lock_irq (&dev->lock);
1844 value = -EINVAL;
1845 if (dev->buf)
1846 goto fail;
1847 dev->buf = kbuf;
1848
1849 /* full or low speed config */
1850 dev->config = (void *) kbuf;
1851 total = le16_to_cpup (&dev->config->wTotalLength);
1852 if (!is_valid_config (dev->config) || total >= length)
1853 goto fail;
1854 kbuf += total;
1855 length -= total;
1856
1857 /* optional high speed config */
1858 if (kbuf [1] == USB_DT_CONFIG) {
1859 dev->hs_config = (void *) kbuf;
1860 total = le16_to_cpup (&dev->hs_config->wTotalLength);
1861 if (!is_valid_config (dev->hs_config) || total >= length)
1862 goto fail;
1863 kbuf += total;
1864 length -= total;
1865 }
1866
1867 /* could support multiple configs, using another encoding! */
1868
1869 /* device descriptor (tweaked for paranoia) */
1870 if (length != USB_DT_DEVICE_SIZE)
1871 goto fail;
1872 dev->dev = (void *)kbuf;
1873 if (dev->dev->bLength != USB_DT_DEVICE_SIZE
1874 || dev->dev->bDescriptorType != USB_DT_DEVICE
1875 || dev->dev->bNumConfigurations != 1)
1876 goto fail;
1877 dev->dev->bNumConfigurations = 1;
1878 dev->dev->bcdUSB = __constant_cpu_to_le16 (0x0200);
1879
1880 /* triggers gadgetfs_bind(); then we can enumerate. */
1881 spin_unlock_irq (&dev->lock);
1882 value = usb_gadget_register_driver (&gadgetfs_driver);
1883 if (value != 0) {
1884 kfree (dev->buf);
1885 dev->buf = NULL;
1886 } else {
1887 /* at this point "good" hardware has for the first time
1888 * let the USB the host see us. alternatively, if users
1889 * unplug/replug that will clear all the error state.
1890 *
1891 * note: everything running before here was guaranteed
1892 * to choke driver model style diagnostics. from here
1893 * on, they can work ... except in cleanup paths that
1894 * kick in after the ep0 descriptor is closed.
1895 */
1896 fd->f_op = &ep0_io_operations;
1897 value = len;
1898 }
1899 return value;
1900
1901 fail:
1902 spin_unlock_irq (&dev->lock);
1903 pr_debug ("%s: %s fail %Zd, %p\n", shortname, __FUNCTION__, value, dev);
1904 kfree (dev->buf);
1905 dev->buf = NULL;
1906 return value;
1907 }
1908
1909 static int
1910 dev_open (struct inode *inode, struct file *fd)
1911 {
1912 struct dev_data *dev = inode->i_private;
1913 int value = -EBUSY;
1914
1915 if (dev->state == STATE_DEV_DISABLED) {
1916 dev->ev_next = 0;
1917 dev->state = STATE_OPENED;
1918 fd->private_data = dev;
1919 get_dev (dev);
1920 value = 0;
1921 }
1922 return value;
1923 }
1924
1925 static struct file_operations dev_init_operations = {
1926 .owner = THIS_MODULE,
1927 .llseek = no_llseek,
1928
1929 .open = dev_open,
1930 .write = dev_config,
1931 .fasync = ep0_fasync,
1932 .ioctl = dev_ioctl,
1933 .release = dev_release,
1934 };
1935
1936 /*----------------------------------------------------------------------*/
1937
1938 /* FILESYSTEM AND SUPERBLOCK OPERATIONS
1939 *
1940 * Mounting the filesystem creates a controller file, used first for
1941 * device configuration then later for event monitoring.
1942 */
1943
1944
1945 /* FIXME PAM etc could set this security policy without mount options
1946 * if epfiles inherited ownership and permissons from ep0 ...
1947 */
1948
1949 static unsigned default_uid;
1950 static unsigned default_gid;
1951 static unsigned default_perm = S_IRUSR | S_IWUSR;
1952
1953 module_param (default_uid, uint, 0644);
1954 module_param (default_gid, uint, 0644);
1955 module_param (default_perm, uint, 0644);
1956
1957
1958 static struct inode *
1959 gadgetfs_make_inode (struct super_block *sb,
1960 void *data, const struct file_operations *fops,
1961 int mode)
1962 {
1963 struct inode *inode = new_inode (sb);
1964
1965 if (inode) {
1966 inode->i_mode = mode;
1967 inode->i_uid = default_uid;
1968 inode->i_gid = default_gid;
1969 inode->i_blocks = 0;
1970 inode->i_atime = inode->i_mtime = inode->i_ctime
1971 = CURRENT_TIME;
1972 inode->i_private = data;
1973 inode->i_fop = fops;
1974 }
1975 return inode;
1976 }
1977
1978 /* creates in fs root directory, so non-renamable and non-linkable.
1979 * so inode and dentry are paired, until device reconfig.
1980 */
1981 static struct inode *
1982 gadgetfs_create_file (struct super_block *sb, char const *name,
1983 void *data, const struct file_operations *fops,
1984 struct dentry **dentry_p)
1985 {
1986 struct dentry *dentry;
1987 struct inode *inode;
1988
1989 dentry = d_alloc_name(sb->s_root, name);
1990 if (!dentry)
1991 return NULL;
1992
1993 inode = gadgetfs_make_inode (sb, data, fops,
1994 S_IFREG | (default_perm & S_IRWXUGO));
1995 if (!inode) {
1996 dput(dentry);
1997 return NULL;
1998 }
1999 d_add (dentry, inode);
2000 *dentry_p = dentry;
2001 return inode;
2002 }
2003
2004 static struct super_operations gadget_fs_operations = {
2005 .statfs = simple_statfs,
2006 .drop_inode = generic_delete_inode,
2007 };
2008
2009 static int
2010 gadgetfs_fill_super (struct super_block *sb, void *opts, int silent)
2011 {
2012 struct inode *inode;
2013 struct dentry *d;
2014 struct dev_data *dev;
2015
2016 if (the_device)
2017 return -ESRCH;
2018
2019 /* fake probe to determine $CHIP */
2020 (void) usb_gadget_register_driver (&probe_driver);
2021 if (!CHIP)
2022 return -ENODEV;
2023
2024 /* superblock */
2025 sb->s_blocksize = PAGE_CACHE_SIZE;
2026 sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
2027 sb->s_magic = GADGETFS_MAGIC;
2028 sb->s_op = &gadget_fs_operations;
2029 sb->s_time_gran = 1;
2030
2031 /* root inode */
2032 inode = gadgetfs_make_inode (sb,
2033 NULL, &simple_dir_operations,
2034 S_IFDIR | S_IRUGO | S_IXUGO);
2035 if (!inode)
2036 goto enomem0;
2037 inode->i_op = &simple_dir_inode_operations;
2038 if (!(d = d_alloc_root (inode)))
2039 goto enomem1;
2040 sb->s_root = d;
2041
2042 /* the ep0 file is named after the controller we expect;
2043 * user mode code can use it for sanity checks, like we do.
2044 */
2045 dev = dev_new ();
2046 if (!dev)
2047 goto enomem2;
2048
2049 dev->sb = sb;
2050 if (!gadgetfs_create_file (sb, CHIP,
2051 dev, &dev_init_operations,
2052 &dev->dentry))
2053 goto enomem3;
2054
2055 /* other endpoint files are available after hardware setup,
2056 * from binding to a controller.
2057 */
2058 the_device = dev;
2059 return 0;
2060
2061 enomem3:
2062 put_dev (dev);
2063 enomem2:
2064 dput (d);
2065 enomem1:
2066 iput (inode);
2067 enomem0:
2068 return -ENOMEM;
2069 }
2070
2071 /* "mount -t gadgetfs path /dev/gadget" ends up here */
2072 static int
2073 gadgetfs_get_sb (struct file_system_type *t, int flags,
2074 const char *path, void *opts, struct vfsmount *mnt)
2075 {
2076 return get_sb_single (t, flags, opts, gadgetfs_fill_super, mnt);
2077 }
2078
2079 static void
2080 gadgetfs_kill_sb (struct super_block *sb)
2081 {
2082 kill_litter_super (sb);
2083 if (the_device) {
2084 put_dev (the_device);
2085 the_device = NULL;
2086 }
2087 }
2088
2089 /*----------------------------------------------------------------------*/
2090
2091 static struct file_system_type gadgetfs_type = {
2092 .owner = THIS_MODULE,
2093 .name = shortname,
2094 .get_sb = gadgetfs_get_sb,
2095 .kill_sb = gadgetfs_kill_sb,
2096 };
2097
2098 /*----------------------------------------------------------------------*/
2099
2100 static int __init init (void)
2101 {
2102 int status;
2103
2104 status = register_filesystem (&gadgetfs_type);
2105 if (status == 0)
2106 pr_info ("%s: %s, version " DRIVER_VERSION "\n",
2107 shortname, driver_desc);
2108 return status;
2109 }
2110 module_init (init);
2111
2112 static void __exit cleanup (void)
2113 {
2114 pr_debug ("unregister %s\n", shortname);
2115 unregister_filesystem (&gadgetfs_type);
2116 }
2117 module_exit (cleanup);
2118
Linux 2.6 libata-dev (mirror)