Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6
[pandora-kernel.git] / drivers / usb / gadget / inode.c
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/sched.h>
34 #include <linux/slab.h>
35 #include <linux/poll.h>
36
37 #include <linux/device.h>
38 #include <linux/moduleparam.h>
39
40 #include <linux/usb/gadgetfs.h>
41 #include <linux/usb/gadget.h>
42
43
44 /*
45  * The gadgetfs API maps each endpoint to a file descriptor so that you
46  * can use standard synchronous read/write calls for I/O.  There's some
47  * O_NONBLOCK and O_ASYNC/FASYNC style i/o support.  Example usermode
48  * drivers show how this works in practice.  You can also use AIO to
49  * eliminate I/O gaps between requests, to help when streaming data.
50  *
51  * Key parts that must be USB-specific are protocols defining how the
52  * read/write operations relate to the hardware state machines.  There
53  * are two types of files.  One type is for the device, implementing ep0.
54  * The other type is for each IN or OUT endpoint.  In both cases, the
55  * user mode driver must configure the hardware before using it.
56  *
57  * - First, dev_config() is called when /dev/gadget/$CHIP is configured
58  *   (by writing configuration and device descriptors).  Afterwards it
59  *   may serve as a source of device events, used to handle all control
60  *   requests other than basic enumeration.
61  *
62  * - Then, after a SET_CONFIGURATION control request, ep_config() is
63  *   called when each /dev/gadget/ep* file is configured (by writing
64  *   endpoint descriptors).  Afterwards these files are used to write()
65  *   IN data or to read() OUT data.  To halt the endpoint, a "wrong
66  *   direction" request is issued (like reading an IN endpoint).
67  *
68  * Unlike "usbfs" the only ioctl()s are for things that are rare, and maybe
69  * not possible on all hardware.  For example, precise fault handling with
70  * respect to data left in endpoint fifos after aborted operations; or
71  * selective clearing of endpoint halts, to implement SET_INTERFACE.
72  */
73
74 #define DRIVER_DESC     "USB Gadget filesystem"
75 #define DRIVER_VERSION  "24 Aug 2004"
76
77 static const char driver_desc [] = DRIVER_DESC;
78 static const char shortname [] = "gadgetfs";
79
80 MODULE_DESCRIPTION (DRIVER_DESC);
81 MODULE_AUTHOR ("David Brownell");
82 MODULE_LICENSE ("GPL");
83
84
85 /*----------------------------------------------------------------------*/
86
87 #define GADGETFS_MAGIC          0xaee71ee7
88 #define DMA_ADDR_INVALID        (~(dma_addr_t)0)
89
90 /* /dev/gadget/$CHIP represents ep0 and the whole device */
91 enum ep0_state {
92         /* DISBLED is the initial state.
93          */
94         STATE_DEV_DISABLED = 0,
95
96         /* Only one open() of /dev/gadget/$CHIP; only one file tracks
97          * ep0/device i/o modes and binding to the controller.  Driver
98          * must always write descriptors to initialize the device, then
99          * the device becomes UNCONNECTED until enumeration.
100          */
101         STATE_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 mutex                    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 (!mutex_trylock(&epdata->lock))
301                         goto nonblock;
302                 if (epdata->state != STATE_EP_ENABLED) {
303                         mutex_unlock(&epdata->lock);
304 nonblock:
305                         val = -EAGAIN;
306                 } else
307                         val = 0;
308                 return val;
309         }
310
311         val = mutex_lock_interruptible(&epdata->lock);
312         if (val < 0)
313                 return val;
314
315         switch (epdata->state) {
316         case STATE_EP_ENABLED:
317                 break;
318         // case STATE_EP_DISABLED:              /* "can't happen" */
319         // case STATE_EP_READY:                 /* "can't happen" */
320         default:                                /* error! */
321                 pr_debug ("%s: ep %p not available, state %d\n",
322                                 shortname, epdata, epdata->state);
323                 // FALLTHROUGH
324         case STATE_EP_UNBOUND:                  /* clean disconnect */
325                 val = -ENODEV;
326                 mutex_unlock(&epdata->lock);
327         }
328         return val;
329 }
330
331 static ssize_t
332 ep_io (struct ep_data *epdata, void *buf, unsigned len)
333 {
334         DECLARE_COMPLETION_ONSTACK (done);
335         int value;
336
337         spin_lock_irq (&epdata->dev->lock);
338         if (likely (epdata->ep != NULL)) {
339                 struct usb_request      *req = epdata->req;
340
341                 req->context = &done;
342                 req->complete = epio_complete;
343                 req->buf = buf;
344                 req->length = len;
345                 value = usb_ep_queue (epdata->ep, req, GFP_ATOMIC);
346         } else
347                 value = -ENODEV;
348         spin_unlock_irq (&epdata->dev->lock);
349
350         if (likely (value == 0)) {
351                 value = wait_event_interruptible (done.wait, done.done);
352                 if (value != 0) {
353                         spin_lock_irq (&epdata->dev->lock);
354                         if (likely (epdata->ep != NULL)) {
355                                 DBG (epdata->dev, "%s i/o interrupted\n",
356                                                 epdata->name);
357                                 usb_ep_dequeue (epdata->ep, epdata->req);
358                                 spin_unlock_irq (&epdata->dev->lock);
359
360                                 wait_event (done.wait, done.done);
361                                 if (epdata->status == -ECONNRESET)
362                                         epdata->status = -EINTR;
363                         } else {
364                                 spin_unlock_irq (&epdata->dev->lock);
365
366                                 DBG (epdata->dev, "endpoint gone\n");
367                                 epdata->status = -ENODEV;
368                         }
369                 }
370                 return epdata->status;
371         }
372         return value;
373 }
374
375
376 /* handle a synchronous OUT bulk/intr/iso transfer */
377 static ssize_t
378 ep_read (struct file *fd, char __user *buf, size_t len, loff_t *ptr)
379 {
380         struct ep_data          *data = fd->private_data;
381         void                    *kbuf;
382         ssize_t                 value;
383
384         if ((value = get_ready_ep (fd->f_flags, data)) < 0)
385                 return value;
386
387         /* halt any endpoint by doing a "wrong direction" i/o call */
388         if (usb_endpoint_dir_in(&data->desc)) {
389                 if (usb_endpoint_xfer_isoc(&data->desc)) {
390                         mutex_unlock(&data->lock);
391                         return -EINVAL;
392                 }
393                 DBG (data->dev, "%s halt\n", data->name);
394                 spin_lock_irq (&data->dev->lock);
395                 if (likely (data->ep != NULL))
396                         usb_ep_set_halt (data->ep);
397                 spin_unlock_irq (&data->dev->lock);
398                 mutex_unlock(&data->lock);
399                 return -EBADMSG;
400         }
401
402         /* FIXME readahead for O_NONBLOCK and poll(); careful with ZLPs */
403
404         value = -ENOMEM;
405         kbuf = kmalloc (len, GFP_KERNEL);
406         if (unlikely (!kbuf))
407                 goto free1;
408
409         value = ep_io (data, kbuf, len);
410         VDEBUG (data->dev, "%s read %zu OUT, status %d\n",
411                 data->name, len, (int) value);
412         if (value >= 0 && copy_to_user (buf, kbuf, value))
413                 value = -EFAULT;
414
415 free1:
416         mutex_unlock(&data->lock);
417         kfree (kbuf);
418         return value;
419 }
420
421 /* handle a synchronous IN bulk/intr/iso transfer */
422 static ssize_t
423 ep_write (struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
424 {
425         struct ep_data          *data = fd->private_data;
426         void                    *kbuf;
427         ssize_t                 value;
428
429         if ((value = get_ready_ep (fd->f_flags, data)) < 0)
430                 return value;
431
432         /* halt any endpoint by doing a "wrong direction" i/o call */
433         if (!usb_endpoint_dir_in(&data->desc)) {
434                 if (usb_endpoint_xfer_isoc(&data->desc))
435                         return -EINVAL;
436                 DBG (data->dev, "%s halt\n", data->name);
437                 spin_lock_irq (&data->dev->lock);
438                 if (likely (data->ep != NULL))
439                         usb_ep_set_halt (data->ep);
440                 spin_unlock_irq (&data->dev->lock);
441                 mutex_unlock(&data->lock);
442                 return -EBADMSG;
443         }
444
445         /* FIXME writebehind for O_NONBLOCK and poll(), qlen = 1 */
446
447         value = -ENOMEM;
448         kbuf = kmalloc (len, GFP_KERNEL);
449         if (!kbuf)
450                 goto free1;
451         if (copy_from_user (kbuf, buf, len)) {
452                 value = -EFAULT;
453                 goto free1;
454         }
455
456         value = ep_io (data, kbuf, len);
457         VDEBUG (data->dev, "%s write %zu IN, status %d\n",
458                 data->name, len, (int) value);
459 free1:
460         mutex_unlock(&data->lock);
461         kfree (kbuf);
462         return value;
463 }
464
465 static int
466 ep_release (struct inode *inode, struct file *fd)
467 {
468         struct ep_data          *data = fd->private_data;
469         int value;
470
471         value = mutex_lock_interruptible(&data->lock);
472         if (value < 0)
473                 return value;
474
475         /* clean up if this can be reopened */
476         if (data->state != STATE_EP_UNBOUND) {
477                 data->state = STATE_EP_DISABLED;
478                 data->desc.bDescriptorType = 0;
479                 data->hs_desc.bDescriptorType = 0;
480                 usb_ep_disable(data->ep);
481         }
482         mutex_unlock(&data->lock);
483         put_ep (data);
484         return 0;
485 }
486
487 static long ep_ioctl(struct file *fd, unsigned code, unsigned long value)
488 {
489         struct ep_data          *data = fd->private_data;
490         int                     status;
491
492         if ((status = get_ready_ep (fd->f_flags, data)) < 0)
493                 return status;
494
495         spin_lock_irq (&data->dev->lock);
496         if (likely (data->ep != NULL)) {
497                 switch (code) {
498                 case GADGETFS_FIFO_STATUS:
499                         status = usb_ep_fifo_status (data->ep);
500                         break;
501                 case GADGETFS_FIFO_FLUSH:
502                         usb_ep_fifo_flush (data->ep);
503                         break;
504                 case GADGETFS_CLEAR_HALT:
505                         status = usb_ep_clear_halt (data->ep);
506                         break;
507                 default:
508                         status = -ENOTTY;
509                 }
510         } else
511                 status = -ENODEV;
512         spin_unlock_irq (&data->dev->lock);
513         mutex_unlock(&data->lock);
514         return status;
515 }
516
517 /*----------------------------------------------------------------------*/
518
519 /* ASYNCHRONOUS ENDPOINT I/O OPERATIONS (bulk/intr/iso) */
520
521 struct kiocb_priv {
522         struct usb_request      *req;
523         struct ep_data          *epdata;
524         void                    *buf;
525         const struct iovec      *iv;
526         unsigned long           nr_segs;
527         unsigned                actual;
528 };
529
530 static int ep_aio_cancel(struct kiocb *iocb, struct io_event *e)
531 {
532         struct kiocb_priv       *priv = iocb->private;
533         struct ep_data          *epdata;
534         int                     value;
535
536         local_irq_disable();
537         epdata = priv->epdata;
538         // spin_lock(&epdata->dev->lock);
539         kiocbSetCancelled(iocb);
540         if (likely(epdata && epdata->ep && priv->req))
541                 value = usb_ep_dequeue (epdata->ep, priv->req);
542         else
543                 value = -EINVAL;
544         // spin_unlock(&epdata->dev->lock);
545         local_irq_enable();
546
547         aio_put_req(iocb);
548         return value;
549 }
550
551 static ssize_t ep_aio_read_retry(struct kiocb *iocb)
552 {
553         struct kiocb_priv       *priv = iocb->private;
554         ssize_t                 len, total;
555         void                    *to_copy;
556         int                     i;
557
558         /* we "retry" to get the right mm context for this: */
559
560         /* copy stuff into user buffers */
561         total = priv->actual;
562         len = 0;
563         to_copy = priv->buf;
564         for (i=0; i < priv->nr_segs; i++) {
565                 ssize_t this = min((ssize_t)(priv->iv[i].iov_len), total);
566
567                 if (copy_to_user(priv->iv[i].iov_base, to_copy, this)) {
568                         if (len == 0)
569                                 len = -EFAULT;
570                         break;
571                 }
572
573                 total -= this;
574                 len += this;
575                 to_copy += this;
576                 if (total == 0)
577                         break;
578         }
579         kfree(priv->buf);
580         kfree(priv);
581         return len;
582 }
583
584 static void ep_aio_complete(struct usb_ep *ep, struct usb_request *req)
585 {
586         struct kiocb            *iocb = req->context;
587         struct kiocb_priv       *priv = iocb->private;
588         struct ep_data          *epdata = priv->epdata;
589
590         /* lock against disconnect (and ideally, cancel) */
591         spin_lock(&epdata->dev->lock);
592         priv->req = NULL;
593         priv->epdata = NULL;
594
595         /* if this was a write or a read returning no data then we
596          * don't need to copy anything to userspace, so we can
597          * complete the aio request immediately.
598          */
599         if (priv->iv == NULL || unlikely(req->actual == 0)) {
600                 kfree(req->buf);
601                 kfree(priv);
602                 iocb->private = NULL;
603                 /* aio_complete() reports bytes-transferred _and_ faults */
604                 aio_complete(iocb, req->actual ? req->actual : req->status,
605                                 req->status);
606         } else {
607                 /* retry() won't report both; so we hide some faults */
608                 if (unlikely(0 != req->status))
609                         DBG(epdata->dev, "%s fault %d len %d\n",
610                                 ep->name, req->status, req->actual);
611
612                 priv->buf = req->buf;
613                 priv->actual = req->actual;
614                 kick_iocb(iocb);
615         }
616         spin_unlock(&epdata->dev->lock);
617
618         usb_ep_free_request(ep, req);
619         put_ep(epdata);
620 }
621
622 static ssize_t
623 ep_aio_rwtail(
624         struct kiocb    *iocb,
625         char            *buf,
626         size_t          len,
627         struct ep_data  *epdata,
628         const struct iovec *iv,
629         unsigned long   nr_segs
630 )
631 {
632         struct kiocb_priv       *priv;
633         struct usb_request      *req;
634         ssize_t                 value;
635
636         priv = kmalloc(sizeof *priv, GFP_KERNEL);
637         if (!priv) {
638                 value = -ENOMEM;
639 fail:
640                 kfree(buf);
641                 return value;
642         }
643         iocb->private = priv;
644         priv->iv = iv;
645         priv->nr_segs = nr_segs;
646
647         value = get_ready_ep(iocb->ki_filp->f_flags, epdata);
648         if (unlikely(value < 0)) {
649                 kfree(priv);
650                 goto fail;
651         }
652
653         iocb->ki_cancel = ep_aio_cancel;
654         get_ep(epdata);
655         priv->epdata = epdata;
656         priv->actual = 0;
657
658         /* each kiocb is coupled to one usb_request, but we can't
659          * allocate or submit those if the host disconnected.
660          */
661         spin_lock_irq(&epdata->dev->lock);
662         if (likely(epdata->ep)) {
663                 req = usb_ep_alloc_request(epdata->ep, GFP_ATOMIC);
664                 if (likely(req)) {
665                         priv->req = req;
666                         req->buf = buf;
667                         req->length = len;
668                         req->complete = ep_aio_complete;
669                         req->context = iocb;
670                         value = usb_ep_queue(epdata->ep, req, GFP_ATOMIC);
671                         if (unlikely(0 != value))
672                                 usb_ep_free_request(epdata->ep, req);
673                 } else
674                         value = -EAGAIN;
675         } else
676                 value = -ENODEV;
677         spin_unlock_irq(&epdata->dev->lock);
678
679         mutex_unlock(&epdata->lock);
680
681         if (unlikely(value)) {
682                 kfree(priv);
683                 put_ep(epdata);
684         } else
685                 value = (iv ? -EIOCBRETRY : -EIOCBQUEUED);
686         return value;
687 }
688
689 static ssize_t
690 ep_aio_read(struct kiocb *iocb, const struct iovec *iov,
691                 unsigned long nr_segs, loff_t o)
692 {
693         struct ep_data          *epdata = iocb->ki_filp->private_data;
694         char                    *buf;
695
696         if (unlikely(usb_endpoint_dir_in(&epdata->desc)))
697                 return -EINVAL;
698
699         buf = kmalloc(iocb->ki_left, GFP_KERNEL);
700         if (unlikely(!buf))
701                 return -ENOMEM;
702
703         iocb->ki_retry = ep_aio_read_retry;
704         return ep_aio_rwtail(iocb, buf, iocb->ki_left, epdata, iov, nr_segs);
705 }
706
707 static ssize_t
708 ep_aio_write(struct kiocb *iocb, const struct iovec *iov,
709                 unsigned long nr_segs, loff_t o)
710 {
711         struct ep_data          *epdata = iocb->ki_filp->private_data;
712         char                    *buf;
713         size_t                  len = 0;
714         int                     i = 0;
715
716         if (unlikely(!usb_endpoint_dir_in(&epdata->desc)))
717                 return -EINVAL;
718
719         buf = kmalloc(iocb->ki_left, GFP_KERNEL);
720         if (unlikely(!buf))
721                 return -ENOMEM;
722
723         for (i=0; i < nr_segs; i++) {
724                 if (unlikely(copy_from_user(&buf[len], iov[i].iov_base,
725                                 iov[i].iov_len) != 0)) {
726                         kfree(buf);
727                         return -EFAULT;
728                 }
729                 len += iov[i].iov_len;
730         }
731         return ep_aio_rwtail(iocb, buf, len, epdata, NULL, 0);
732 }
733
734 /*----------------------------------------------------------------------*/
735
736 /* used after endpoint configuration */
737 static const struct file_operations ep_io_operations = {
738         .owner =        THIS_MODULE,
739         .llseek =       no_llseek,
740
741         .read =         ep_read,
742         .write =        ep_write,
743         .unlocked_ioctl = ep_ioctl,
744         .release =      ep_release,
745
746         .aio_read =     ep_aio_read,
747         .aio_write =    ep_aio_write,
748 };
749
750 /* ENDPOINT INITIALIZATION
751  *
752  *     fd = open ("/dev/gadget/$ENDPOINT", O_RDWR)
753  *     status = write (fd, descriptors, sizeof descriptors)
754  *
755  * That write establishes the endpoint configuration, configuring
756  * the controller to process bulk, interrupt, or isochronous transfers
757  * at the right maxpacket size, and so on.
758  *
759  * The descriptors are message type 1, identified by a host order u32
760  * at the beginning of what's written.  Descriptor order is: full/low
761  * speed descriptor, then optional high speed descriptor.
762  */
763 static ssize_t
764 ep_config (struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
765 {
766         struct ep_data          *data = fd->private_data;
767         struct usb_ep           *ep;
768         u32                     tag;
769         int                     value, length = len;
770
771         value = mutex_lock_interruptible(&data->lock);
772         if (value < 0)
773                 return value;
774
775         if (data->state != STATE_EP_READY) {
776                 value = -EL2HLT;
777                 goto fail;
778         }
779
780         value = len;
781         if (len < USB_DT_ENDPOINT_SIZE + 4)
782                 goto fail0;
783
784         /* we might need to change message format someday */
785         if (copy_from_user (&tag, buf, 4)) {
786                 goto fail1;
787         }
788         if (tag != 1) {
789                 DBG(data->dev, "config %s, bad tag %d\n", data->name, tag);
790                 goto fail0;
791         }
792         buf += 4;
793         len -= 4;
794
795         /* NOTE:  audio endpoint extensions not accepted here;
796          * just don't include the extra bytes.
797          */
798
799         /* full/low speed descriptor, then high speed */
800         if (copy_from_user (&data->desc, buf, USB_DT_ENDPOINT_SIZE)) {
801                 goto fail1;
802         }
803         if (data->desc.bLength != USB_DT_ENDPOINT_SIZE
804                         || data->desc.bDescriptorType != USB_DT_ENDPOINT)
805                 goto fail0;
806         if (len != USB_DT_ENDPOINT_SIZE) {
807                 if (len != 2 * USB_DT_ENDPOINT_SIZE)
808                         goto fail0;
809                 if (copy_from_user (&data->hs_desc, buf + USB_DT_ENDPOINT_SIZE,
810                                         USB_DT_ENDPOINT_SIZE)) {
811                         goto fail1;
812                 }
813                 if (data->hs_desc.bLength != USB_DT_ENDPOINT_SIZE
814                                 || data->hs_desc.bDescriptorType
815                                         != USB_DT_ENDPOINT) {
816                         DBG(data->dev, "config %s, bad hs length or type\n",
817                                         data->name);
818                         goto fail0;
819                 }
820         }
821
822         spin_lock_irq (&data->dev->lock);
823         if (data->dev->state == STATE_DEV_UNBOUND) {
824                 value = -ENOENT;
825                 goto gone;
826         } else if ((ep = data->ep) == NULL) {
827                 value = -ENODEV;
828                 goto gone;
829         }
830         switch (data->dev->gadget->speed) {
831         case USB_SPEED_LOW:
832         case USB_SPEED_FULL:
833                 value = usb_ep_enable (ep, &data->desc);
834                 if (value == 0)
835                         data->state = STATE_EP_ENABLED;
836                 break;
837 #ifdef  CONFIG_USB_GADGET_DUALSPEED
838         case USB_SPEED_HIGH:
839                 /* fails if caller didn't provide that descriptor... */
840                 value = usb_ep_enable (ep, &data->hs_desc);
841                 if (value == 0)
842                         data->state = STATE_EP_ENABLED;
843                 break;
844 #endif
845         default:
846                 DBG(data->dev, "unconnected, %s init abandoned\n",
847                                 data->name);
848                 value = -EINVAL;
849         }
850         if (value == 0) {
851                 fd->f_op = &ep_io_operations;
852                 value = length;
853         }
854 gone:
855         spin_unlock_irq (&data->dev->lock);
856         if (value < 0) {
857 fail:
858                 data->desc.bDescriptorType = 0;
859                 data->hs_desc.bDescriptorType = 0;
860         }
861         mutex_unlock(&data->lock);
862         return value;
863 fail0:
864         value = -EINVAL;
865         goto fail;
866 fail1:
867         value = -EFAULT;
868         goto fail;
869 }
870
871 static int
872 ep_open (struct inode *inode, struct file *fd)
873 {
874         struct ep_data          *data = inode->i_private;
875         int                     value = -EBUSY;
876
877         if (mutex_lock_interruptible(&data->lock) != 0)
878                 return -EINTR;
879         spin_lock_irq (&data->dev->lock);
880         if (data->dev->state == STATE_DEV_UNBOUND)
881                 value = -ENOENT;
882         else if (data->state == STATE_EP_DISABLED) {
883                 value = 0;
884                 data->state = STATE_EP_READY;
885                 get_ep (data);
886                 fd->private_data = data;
887                 VDEBUG (data->dev, "%s ready\n", data->name);
888         } else
889                 DBG (data->dev, "%s state %d\n",
890                         data->name, data->state);
891         spin_unlock_irq (&data->dev->lock);
892         mutex_unlock(&data->lock);
893         return value;
894 }
895
896 /* used before endpoint configuration */
897 static const struct file_operations ep_config_operations = {
898         .owner =        THIS_MODULE,
899         .llseek =       no_llseek,
900
901         .open =         ep_open,
902         .write =        ep_config,
903         .release =      ep_release,
904 };
905
906 /*----------------------------------------------------------------------*/
907
908 /* EP0 IMPLEMENTATION can be partly in userspace.
909  *
910  * Drivers that use this facility receive various events, including
911  * control requests the kernel doesn't handle.  Drivers that don't
912  * use this facility may be too simple-minded for real applications.
913  */
914
915 static inline void ep0_readable (struct dev_data *dev)
916 {
917         wake_up (&dev->wait);
918         kill_fasync (&dev->fasync, SIGIO, POLL_IN);
919 }
920
921 static void clean_req (struct usb_ep *ep, struct usb_request *req)
922 {
923         struct dev_data         *dev = ep->driver_data;
924
925         if (req->buf != dev->rbuf) {
926                 kfree(req->buf);
927                 req->buf = dev->rbuf;
928                 req->dma = DMA_ADDR_INVALID;
929         }
930         req->complete = epio_complete;
931         dev->setup_out_ready = 0;
932 }
933
934 static void ep0_complete (struct usb_ep *ep, struct usb_request *req)
935 {
936         struct dev_data         *dev = ep->driver_data;
937         unsigned long           flags;
938         int                     free = 1;
939
940         /* for control OUT, data must still get to userspace */
941         spin_lock_irqsave(&dev->lock, flags);
942         if (!dev->setup_in) {
943                 dev->setup_out_error = (req->status != 0);
944                 if (!dev->setup_out_error)
945                         free = 0;
946                 dev->setup_out_ready = 1;
947                 ep0_readable (dev);
948         }
949
950         /* clean up as appropriate */
951         if (free && req->buf != &dev->rbuf)
952                 clean_req (ep, req);
953         req->complete = epio_complete;
954         spin_unlock_irqrestore(&dev->lock, flags);
955 }
956
957 static int setup_req (struct usb_ep *ep, struct usb_request *req, u16 len)
958 {
959         struct dev_data *dev = ep->driver_data;
960
961         if (dev->setup_out_ready) {
962                 DBG (dev, "ep0 request busy!\n");
963                 return -EBUSY;
964         }
965         if (len > sizeof (dev->rbuf))
966                 req->buf = kmalloc(len, GFP_ATOMIC);
967         if (req->buf == NULL) {
968                 req->buf = dev->rbuf;
969                 return -ENOMEM;
970         }
971         req->complete = ep0_complete;
972         req->length = len;
973         req->zero = 0;
974         return 0;
975 }
976
977 static ssize_t
978 ep0_read (struct file *fd, char __user *buf, size_t len, loff_t *ptr)
979 {
980         struct dev_data                 *dev = fd->private_data;
981         ssize_t                         retval;
982         enum ep0_state                  state;
983
984         spin_lock_irq (&dev->lock);
985
986         /* report fd mode change before acting on it */
987         if (dev->setup_abort) {
988                 dev->setup_abort = 0;
989                 retval = -EIDRM;
990                 goto done;
991         }
992
993         /* control DATA stage */
994         if ((state = dev->state) == STATE_DEV_SETUP) {
995
996                 if (dev->setup_in) {            /* stall IN */
997                         VDEBUG(dev, "ep0in stall\n");
998                         (void) usb_ep_set_halt (dev->gadget->ep0);
999                         retval = -EL2HLT;
1000                         dev->state = STATE_DEV_CONNECTED;
1001
1002                 } else if (len == 0) {          /* ack SET_CONFIGURATION etc */
1003                         struct usb_ep           *ep = dev->gadget->ep0;
1004                         struct usb_request      *req = dev->req;
1005
1006                         if ((retval = setup_req (ep, req, 0)) == 0)
1007                                 retval = usb_ep_queue (ep, req, GFP_ATOMIC);
1008                         dev->state = STATE_DEV_CONNECTED;
1009
1010                         /* assume that was SET_CONFIGURATION */
1011                         if (dev->current_config) {
1012                                 unsigned power;
1013
1014                                 if (gadget_is_dualspeed(dev->gadget)
1015                                                 && (dev->gadget->speed
1016                                                         == USB_SPEED_HIGH))
1017                                         power = dev->hs_config->bMaxPower;
1018                                 else
1019                                         power = dev->config->bMaxPower;
1020                                 usb_gadget_vbus_draw(dev->gadget, 2 * power);
1021                         }
1022
1023                 } else {                        /* collect OUT data */
1024                         if ((fd->f_flags & O_NONBLOCK) != 0
1025                                         && !dev->setup_out_ready) {
1026                                 retval = -EAGAIN;
1027                                 goto done;
1028                         }
1029                         spin_unlock_irq (&dev->lock);
1030                         retval = wait_event_interruptible (dev->wait,
1031                                         dev->setup_out_ready != 0);
1032
1033                         /* FIXME state could change from under us */
1034                         spin_lock_irq (&dev->lock);
1035                         if (retval)
1036                                 goto done;
1037
1038                         if (dev->state != STATE_DEV_SETUP) {
1039                                 retval = -ECANCELED;
1040                                 goto done;
1041                         }
1042                         dev->state = STATE_DEV_CONNECTED;
1043
1044                         if (dev->setup_out_error)
1045                                 retval = -EIO;
1046                         else {
1047                                 len = min (len, (size_t)dev->req->actual);
1048 // FIXME don't call this with the spinlock held ...
1049                                 if (copy_to_user (buf, dev->req->buf, len))
1050                                         retval = -EFAULT;
1051                                 clean_req (dev->gadget->ep0, dev->req);
1052                                 /* NOTE userspace can't yet choose to stall */
1053                         }
1054                 }
1055                 goto done;
1056         }
1057
1058         /* else normal: return event data */
1059         if (len < sizeof dev->event [0]) {
1060                 retval = -EINVAL;
1061                 goto done;
1062         }
1063         len -= len % sizeof (struct usb_gadgetfs_event);
1064         dev->usermode_setup = 1;
1065
1066 scan:
1067         /* return queued events right away */
1068         if (dev->ev_next != 0) {
1069                 unsigned                i, n;
1070
1071                 n = len / sizeof (struct usb_gadgetfs_event);
1072                 if (dev->ev_next < n)
1073                         n = dev->ev_next;
1074
1075                 /* ep0 i/o has special semantics during STATE_DEV_SETUP */
1076                 for (i = 0; i < n; i++) {
1077                         if (dev->event [i].type == GADGETFS_SETUP) {
1078                                 dev->state = STATE_DEV_SETUP;
1079                                 n = i + 1;
1080                                 break;
1081                         }
1082                 }
1083                 spin_unlock_irq (&dev->lock);
1084                 len = n * sizeof (struct usb_gadgetfs_event);
1085                 if (copy_to_user (buf, &dev->event, len))
1086                         retval = -EFAULT;
1087                 else
1088                         retval = len;
1089                 if (len > 0) {
1090                         /* NOTE this doesn't guard against broken drivers;
1091                          * concurrent ep0 readers may lose events.
1092                          */
1093                         spin_lock_irq (&dev->lock);
1094                         if (dev->ev_next > n) {
1095                                 memmove(&dev->event[0], &dev->event[n],
1096                                         sizeof (struct usb_gadgetfs_event)
1097                                                 * (dev->ev_next - n));
1098                         }
1099                         dev->ev_next -= n;
1100                         spin_unlock_irq (&dev->lock);
1101                 }
1102                 return retval;
1103         }
1104         if (fd->f_flags & O_NONBLOCK) {
1105                 retval = -EAGAIN;
1106                 goto done;
1107         }
1108
1109         switch (state) {
1110         default:
1111                 DBG (dev, "fail %s, state %d\n", __func__, state);
1112                 retval = -ESRCH;
1113                 break;
1114         case STATE_DEV_UNCONNECTED:
1115         case STATE_DEV_CONNECTED:
1116                 spin_unlock_irq (&dev->lock);
1117                 DBG (dev, "%s wait\n", __func__);
1118
1119                 /* wait for events */
1120                 retval = wait_event_interruptible (dev->wait,
1121                                 dev->ev_next != 0);
1122                 if (retval < 0)
1123                         return retval;
1124                 spin_lock_irq (&dev->lock);
1125                 goto scan;
1126         }
1127
1128 done:
1129         spin_unlock_irq (&dev->lock);
1130         return retval;
1131 }
1132
1133 static struct usb_gadgetfs_event *
1134 next_event (struct dev_data *dev, enum usb_gadgetfs_event_type type)
1135 {
1136         struct usb_gadgetfs_event       *event;
1137         unsigned                        i;
1138
1139         switch (type) {
1140         /* these events purge the queue */
1141         case GADGETFS_DISCONNECT:
1142                 if (dev->state == STATE_DEV_SETUP)
1143                         dev->setup_abort = 1;
1144                 // FALL THROUGH
1145         case GADGETFS_CONNECT:
1146                 dev->ev_next = 0;
1147                 break;
1148         case GADGETFS_SETUP:            /* previous request timed out */
1149         case GADGETFS_SUSPEND:          /* same effect */
1150                 /* these events can't be repeated */
1151                 for (i = 0; i != dev->ev_next; i++) {
1152                         if (dev->event [i].type != type)
1153                                 continue;
1154                         DBG(dev, "discard old event[%d] %d\n", i, type);
1155                         dev->ev_next--;
1156                         if (i == dev->ev_next)
1157                                 break;
1158                         /* indices start at zero, for simplicity */
1159                         memmove (&dev->event [i], &dev->event [i + 1],
1160                                 sizeof (struct usb_gadgetfs_event)
1161                                         * (dev->ev_next - i));
1162                 }
1163                 break;
1164         default:
1165                 BUG ();
1166         }
1167         VDEBUG(dev, "event[%d] = %d\n", dev->ev_next, type);
1168         event = &dev->event [dev->ev_next++];
1169         BUG_ON (dev->ev_next > N_EVENT);
1170         memset (event, 0, sizeof *event);
1171         event->type = type;
1172         return event;
1173 }
1174
1175 static ssize_t
1176 ep0_write (struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
1177 {
1178         struct dev_data         *dev = fd->private_data;
1179         ssize_t                 retval = -ESRCH;
1180
1181         spin_lock_irq (&dev->lock);
1182
1183         /* report fd mode change before acting on it */
1184         if (dev->setup_abort) {
1185                 dev->setup_abort = 0;
1186                 retval = -EIDRM;
1187
1188         /* data and/or status stage for control request */
1189         } else if (dev->state == STATE_DEV_SETUP) {
1190
1191                 /* IN DATA+STATUS caller makes len <= wLength */
1192                 if (dev->setup_in) {
1193                         retval = setup_req (dev->gadget->ep0, dev->req, len);
1194                         if (retval == 0) {
1195                                 dev->state = STATE_DEV_CONNECTED;
1196                                 spin_unlock_irq (&dev->lock);
1197                                 if (copy_from_user (dev->req->buf, buf, len))
1198                                         retval = -EFAULT;
1199                                 else {
1200                                         if (len < dev->setup_wLength)
1201                                                 dev->req->zero = 1;
1202                                         retval = usb_ep_queue (
1203                                                 dev->gadget->ep0, dev->req,
1204                                                 GFP_KERNEL);
1205                                 }
1206                                 if (retval < 0) {
1207                                         spin_lock_irq (&dev->lock);
1208                                         clean_req (dev->gadget->ep0, dev->req);
1209                                         spin_unlock_irq (&dev->lock);
1210                                 } else
1211                                         retval = len;
1212
1213                                 return retval;
1214                         }
1215
1216                 /* can stall some OUT transfers */
1217                 } else if (dev->setup_can_stall) {
1218                         VDEBUG(dev, "ep0out stall\n");
1219                         (void) usb_ep_set_halt (dev->gadget->ep0);
1220                         retval = -EL2HLT;
1221                         dev->state = STATE_DEV_CONNECTED;
1222                 } else {
1223                         DBG(dev, "bogus ep0out stall!\n");
1224                 }
1225         } else
1226                 DBG (dev, "fail %s, state %d\n", __func__, dev->state);
1227
1228         spin_unlock_irq (&dev->lock);
1229         return retval;
1230 }
1231
1232 static int
1233 ep0_fasync (int f, struct file *fd, int on)
1234 {
1235         struct dev_data         *dev = fd->private_data;
1236         // caller must F_SETOWN before signal delivery happens
1237         VDEBUG (dev, "%s %s\n", __func__, on ? "on" : "off");
1238         return fasync_helper (f, fd, on, &dev->fasync);
1239 }
1240
1241 static struct usb_gadget_driver gadgetfs_driver;
1242
1243 static int
1244 dev_release (struct inode *inode, struct file *fd)
1245 {
1246         struct dev_data         *dev = fd->private_data;
1247
1248         /* closing ep0 === shutdown all */
1249
1250         usb_gadget_unregister_driver (&gadgetfs_driver);
1251
1252         /* at this point "good" hardware has disconnected the
1253          * device from USB; the host won't see it any more.
1254          * alternatively, all host requests will time out.
1255          */
1256
1257         kfree (dev->buf);
1258         dev->buf = NULL;
1259         put_dev (dev);
1260
1261         /* other endpoints were all decoupled from this device */
1262         spin_lock_irq(&dev->lock);
1263         dev->state = STATE_DEV_DISABLED;
1264         spin_unlock_irq(&dev->lock);
1265         return 0;
1266 }
1267
1268 static unsigned int
1269 ep0_poll (struct file *fd, poll_table *wait)
1270 {
1271        struct dev_data         *dev = fd->private_data;
1272        int                     mask = 0;
1273
1274        poll_wait(fd, &dev->wait, wait);
1275
1276        spin_lock_irq (&dev->lock);
1277
1278        /* report fd mode change before acting on it */
1279        if (dev->setup_abort) {
1280                dev->setup_abort = 0;
1281                mask = POLLHUP;
1282                goto out;
1283        }
1284
1285        if (dev->state == STATE_DEV_SETUP) {
1286                if (dev->setup_in || dev->setup_can_stall)
1287                        mask = POLLOUT;
1288        } else {
1289                if (dev->ev_next != 0)
1290                        mask = POLLIN;
1291        }
1292 out:
1293        spin_unlock_irq(&dev->lock);
1294        return mask;
1295 }
1296
1297 static long dev_ioctl (struct file *fd, unsigned code, unsigned long value)
1298 {
1299         struct dev_data         *dev = fd->private_data;
1300         struct usb_gadget       *gadget = dev->gadget;
1301         long ret = -ENOTTY;
1302
1303         if (gadget->ops->ioctl)
1304                 ret = gadget->ops->ioctl (gadget, code, value);
1305
1306         return ret;
1307 }
1308
1309 /* used after device configuration */
1310 static const struct file_operations ep0_io_operations = {
1311         .owner =        THIS_MODULE,
1312         .llseek =       no_llseek,
1313
1314         .read =         ep0_read,
1315         .write =        ep0_write,
1316         .fasync =       ep0_fasync,
1317         .poll =         ep0_poll,
1318         .unlocked_ioctl =       dev_ioctl,
1319         .release =      dev_release,
1320 };
1321
1322 /*----------------------------------------------------------------------*/
1323
1324 /* The in-kernel gadget driver handles most ep0 issues, in particular
1325  * enumerating the single configuration (as provided from user space).
1326  *
1327  * Unrecognized ep0 requests may be handled in user space.
1328  */
1329
1330 #ifdef  CONFIG_USB_GADGET_DUALSPEED
1331 static void make_qualifier (struct dev_data *dev)
1332 {
1333         struct usb_qualifier_descriptor         qual;
1334         struct usb_device_descriptor            *desc;
1335
1336         qual.bLength = sizeof qual;
1337         qual.bDescriptorType = USB_DT_DEVICE_QUALIFIER;
1338         qual.bcdUSB = cpu_to_le16 (0x0200);
1339
1340         desc = dev->dev;
1341         qual.bDeviceClass = desc->bDeviceClass;
1342         qual.bDeviceSubClass = desc->bDeviceSubClass;
1343         qual.bDeviceProtocol = desc->bDeviceProtocol;
1344
1345         /* assumes ep0 uses the same value for both speeds ... */
1346         qual.bMaxPacketSize0 = desc->bMaxPacketSize0;
1347
1348         qual.bNumConfigurations = 1;
1349         qual.bRESERVED = 0;
1350
1351         memcpy (dev->rbuf, &qual, sizeof qual);
1352 }
1353 #endif
1354
1355 static int
1356 config_buf (struct dev_data *dev, u8 type, unsigned index)
1357 {
1358         int             len;
1359         int             hs = 0;
1360
1361         /* only one configuration */
1362         if (index > 0)
1363                 return -EINVAL;
1364
1365         if (gadget_is_dualspeed(dev->gadget)) {
1366                 hs = (dev->gadget->speed == USB_SPEED_HIGH);
1367                 if (type == USB_DT_OTHER_SPEED_CONFIG)
1368                         hs = !hs;
1369         }
1370         if (hs) {
1371                 dev->req->buf = dev->hs_config;
1372                 len = le16_to_cpu(dev->hs_config->wTotalLength);
1373         } else {
1374                 dev->req->buf = dev->config;
1375                 len = le16_to_cpu(dev->config->wTotalLength);
1376         }
1377         ((u8 *)dev->req->buf) [1] = type;
1378         return len;
1379 }
1380
1381 static int
1382 gadgetfs_setup (struct usb_gadget *gadget, const struct usb_ctrlrequest *ctrl)
1383 {
1384         struct dev_data                 *dev = get_gadget_data (gadget);
1385         struct usb_request              *req = dev->req;
1386         int                             value = -EOPNOTSUPP;
1387         struct usb_gadgetfs_event       *event;
1388         u16                             w_value = le16_to_cpu(ctrl->wValue);
1389         u16                             w_length = le16_to_cpu(ctrl->wLength);
1390
1391         spin_lock (&dev->lock);
1392         dev->setup_abort = 0;
1393         if (dev->state == STATE_DEV_UNCONNECTED) {
1394                 if (gadget_is_dualspeed(gadget)
1395                                 && gadget->speed == USB_SPEED_HIGH
1396                                 && dev->hs_config == NULL) {
1397                         spin_unlock(&dev->lock);
1398                         ERROR (dev, "no high speed config??\n");
1399                         return -EINVAL;
1400                 }
1401
1402                 dev->state = STATE_DEV_CONNECTED;
1403                 dev->dev->bMaxPacketSize0 = gadget->ep0->maxpacket;
1404
1405                 INFO (dev, "connected\n");
1406                 event = next_event (dev, GADGETFS_CONNECT);
1407                 event->u.speed = gadget->speed;
1408                 ep0_readable (dev);
1409
1410         /* host may have given up waiting for response.  we can miss control
1411          * requests handled lower down (device/endpoint status and features);
1412          * then ep0_{read,write} will report the wrong status. controller
1413          * driver will have aborted pending i/o.
1414          */
1415         } else if (dev->state == STATE_DEV_SETUP)
1416                 dev->setup_abort = 1;
1417
1418         req->buf = dev->rbuf;
1419         req->dma = DMA_ADDR_INVALID;
1420         req->context = NULL;
1421         value = -EOPNOTSUPP;
1422         switch (ctrl->bRequest) {
1423
1424         case USB_REQ_GET_DESCRIPTOR:
1425                 if (ctrl->bRequestType != USB_DIR_IN)
1426                         goto unrecognized;
1427                 switch (w_value >> 8) {
1428
1429                 case USB_DT_DEVICE:
1430                         value = min (w_length, (u16) sizeof *dev->dev);
1431                         req->buf = dev->dev;
1432                         break;
1433 #ifdef  CONFIG_USB_GADGET_DUALSPEED
1434                 case USB_DT_DEVICE_QUALIFIER:
1435                         if (!dev->hs_config)
1436                                 break;
1437                         value = min (w_length, (u16)
1438                                 sizeof (struct usb_qualifier_descriptor));
1439                         make_qualifier (dev);
1440                         break;
1441                 case USB_DT_OTHER_SPEED_CONFIG:
1442                         // FALLTHROUGH
1443 #endif
1444                 case USB_DT_CONFIG:
1445                         value = config_buf (dev,
1446                                         w_value >> 8,
1447                                         w_value & 0xff);
1448                         if (value >= 0)
1449                                 value = min (w_length, (u16) value);
1450                         break;
1451                 case USB_DT_STRING:
1452                         goto unrecognized;
1453
1454                 default:                // all others are errors
1455                         break;
1456                 }
1457                 break;
1458
1459         /* currently one config, two speeds */
1460         case USB_REQ_SET_CONFIGURATION:
1461                 if (ctrl->bRequestType != 0)
1462                         goto unrecognized;
1463                 if (0 == (u8) w_value) {
1464                         value = 0;
1465                         dev->current_config = 0;
1466                         usb_gadget_vbus_draw(gadget, 8 /* mA */ );
1467                         // user mode expected to disable endpoints
1468                 } else {
1469                         u8      config, power;
1470
1471                         if (gadget_is_dualspeed(gadget)
1472                                         && gadget->speed == USB_SPEED_HIGH) {
1473                                 config = dev->hs_config->bConfigurationValue;
1474                                 power = dev->hs_config->bMaxPower;
1475                         } else {
1476                                 config = dev->config->bConfigurationValue;
1477                                 power = dev->config->bMaxPower;
1478                         }
1479
1480                         if (config == (u8) w_value) {
1481                                 value = 0;
1482                                 dev->current_config = config;
1483                                 usb_gadget_vbus_draw(gadget, 2 * power);
1484                         }
1485                 }
1486
1487                 /* report SET_CONFIGURATION like any other control request,
1488                  * except that usermode may not stall this.  the next
1489                  * request mustn't be allowed start until this finishes:
1490                  * endpoints and threads set up, etc.
1491                  *
1492                  * NOTE:  older PXA hardware (before PXA 255: without UDCCFR)
1493                  * has bad/racey automagic that prevents synchronizing here.
1494                  * even kernel mode drivers often miss them.
1495                  */
1496                 if (value == 0) {
1497                         INFO (dev, "configuration #%d\n", dev->current_config);
1498                         if (dev->usermode_setup) {
1499                                 dev->setup_can_stall = 0;
1500                                 goto delegate;
1501                         }
1502                 }
1503                 break;
1504
1505 #ifndef CONFIG_USB_GADGET_PXA25X
1506         /* PXA automagically handles this request too */
1507         case USB_REQ_GET_CONFIGURATION:
1508                 if (ctrl->bRequestType != 0x80)
1509                         goto unrecognized;
1510                 *(u8 *)req->buf = dev->current_config;
1511                 value = min (w_length, (u16) 1);
1512                 break;
1513 #endif
1514
1515         default:
1516 unrecognized:
1517                 VDEBUG (dev, "%s req%02x.%02x v%04x i%04x l%d\n",
1518                         dev->usermode_setup ? "delegate" : "fail",
1519                         ctrl->bRequestType, ctrl->bRequest,
1520                         w_value, le16_to_cpu(ctrl->wIndex), w_length);
1521
1522                 /* if there's an ep0 reader, don't stall */
1523                 if (dev->usermode_setup) {
1524                         dev->setup_can_stall = 1;
1525 delegate:
1526                         dev->setup_in = (ctrl->bRequestType & USB_DIR_IN)
1527                                                 ? 1 : 0;
1528                         dev->setup_wLength = w_length;
1529                         dev->setup_out_ready = 0;
1530                         dev->setup_out_error = 0;
1531                         value = 0;
1532
1533                         /* read DATA stage for OUT right away */
1534                         if (unlikely (!dev->setup_in && w_length)) {
1535                                 value = setup_req (gadget->ep0, dev->req,
1536                                                         w_length);
1537                                 if (value < 0)
1538                                         break;
1539                                 value = usb_ep_queue (gadget->ep0, dev->req,
1540                                                         GFP_ATOMIC);
1541                                 if (value < 0) {
1542                                         clean_req (gadget->ep0, dev->req);
1543                                         break;
1544                                 }
1545
1546                                 /* we can't currently stall these */
1547                                 dev->setup_can_stall = 0;
1548                         }
1549
1550                         /* state changes when reader collects event */
1551                         event = next_event (dev, GADGETFS_SETUP);
1552                         event->u.setup = *ctrl;
1553                         ep0_readable (dev);
1554                         spin_unlock (&dev->lock);
1555                         return 0;
1556                 }
1557         }
1558
1559         /* proceed with data transfer and status phases? */
1560         if (value >= 0 && dev->state != STATE_DEV_SETUP) {
1561                 req->length = value;
1562                 req->zero = value < w_length;
1563                 value = usb_ep_queue (gadget->ep0, req, GFP_ATOMIC);
1564                 if (value < 0) {
1565                         DBG (dev, "ep_queue --> %d\n", value);
1566                         req->status = 0;
1567                 }
1568         }
1569
1570         /* device stalls when value < 0 */
1571         spin_unlock (&dev->lock);
1572         return value;
1573 }
1574
1575 static void destroy_ep_files (struct dev_data *dev)
1576 {
1577         struct list_head        *entry, *tmp;
1578
1579         DBG (dev, "%s %d\n", __func__, dev->state);
1580
1581         /* dev->state must prevent interference */
1582 restart:
1583         spin_lock_irq (&dev->lock);
1584         list_for_each_safe (entry, tmp, &dev->epfiles) {
1585                 struct ep_data  *ep;
1586                 struct inode    *parent;
1587                 struct dentry   *dentry;
1588
1589                 /* break link to FS */
1590                 ep = list_entry (entry, struct ep_data, epfiles);
1591                 list_del_init (&ep->epfiles);
1592                 dentry = ep->dentry;
1593                 ep->dentry = NULL;
1594                 parent = dentry->d_parent->d_inode;
1595
1596                 /* break link to controller */
1597                 if (ep->state == STATE_EP_ENABLED)
1598                         (void) usb_ep_disable (ep->ep);
1599                 ep->state = STATE_EP_UNBOUND;
1600                 usb_ep_free_request (ep->ep, ep->req);
1601                 ep->ep = NULL;
1602                 wake_up (&ep->wait);
1603                 put_ep (ep);
1604
1605                 spin_unlock_irq (&dev->lock);
1606
1607                 /* break link to dcache */
1608                 mutex_lock (&parent->i_mutex);
1609                 d_delete (dentry);
1610                 dput (dentry);
1611                 mutex_unlock (&parent->i_mutex);
1612
1613                 /* fds may still be open */
1614                 goto restart;
1615         }
1616         spin_unlock_irq (&dev->lock);
1617 }
1618
1619
1620 static struct inode *
1621 gadgetfs_create_file (struct super_block *sb, char const *name,
1622                 void *data, const struct file_operations *fops,
1623                 struct dentry **dentry_p);
1624
1625 static int activate_ep_files (struct dev_data *dev)
1626 {
1627         struct usb_ep   *ep;
1628         struct ep_data  *data;
1629
1630         gadget_for_each_ep (ep, dev->gadget) {
1631
1632                 data = kzalloc(sizeof(*data), GFP_KERNEL);
1633                 if (!data)
1634                         goto enomem0;
1635                 data->state = STATE_EP_DISABLED;
1636                 mutex_init(&data->lock);
1637                 init_waitqueue_head (&data->wait);
1638
1639                 strncpy (data->name, ep->name, sizeof (data->name) - 1);
1640                 atomic_set (&data->count, 1);
1641                 data->dev = dev;
1642                 get_dev (dev);
1643
1644                 data->ep = ep;
1645                 ep->driver_data = data;
1646
1647                 data->req = usb_ep_alloc_request (ep, GFP_KERNEL);
1648                 if (!data->req)
1649                         goto enomem1;
1650
1651                 data->inode = gadgetfs_create_file (dev->sb, data->name,
1652                                 data, &ep_config_operations,
1653                                 &data->dentry);
1654                 if (!data->inode)
1655                         goto enomem2;
1656                 list_add_tail (&data->epfiles, &dev->epfiles);
1657         }
1658         return 0;
1659
1660 enomem2:
1661         usb_ep_free_request (ep, data->req);
1662 enomem1:
1663         put_dev (dev);
1664         kfree (data);
1665 enomem0:
1666         DBG (dev, "%s enomem\n", __func__);
1667         destroy_ep_files (dev);
1668         return -ENOMEM;
1669 }
1670
1671 static void
1672 gadgetfs_unbind (struct usb_gadget *gadget)
1673 {
1674         struct dev_data         *dev = get_gadget_data (gadget);
1675
1676         DBG (dev, "%s\n", __func__);
1677
1678         spin_lock_irq (&dev->lock);
1679         dev->state = STATE_DEV_UNBOUND;
1680         spin_unlock_irq (&dev->lock);
1681
1682         destroy_ep_files (dev);
1683         gadget->ep0->driver_data = NULL;
1684         set_gadget_data (gadget, NULL);
1685
1686         /* we've already been disconnected ... no i/o is active */
1687         if (dev->req)
1688                 usb_ep_free_request (gadget->ep0, dev->req);
1689         DBG (dev, "%s done\n", __func__);
1690         put_dev (dev);
1691 }
1692
1693 static struct dev_data          *the_device;
1694
1695 static int
1696 gadgetfs_bind (struct usb_gadget *gadget)
1697 {
1698         struct dev_data         *dev = the_device;
1699
1700         if (!dev)
1701                 return -ESRCH;
1702         if (0 != strcmp (CHIP, gadget->name)) {
1703                 pr_err("%s expected %s controller not %s\n",
1704                         shortname, CHIP, gadget->name);
1705                 return -ENODEV;
1706         }
1707
1708         set_gadget_data (gadget, dev);
1709         dev->gadget = gadget;
1710         gadget->ep0->driver_data = dev;
1711         dev->dev->bMaxPacketSize0 = gadget->ep0->maxpacket;
1712
1713         /* preallocate control response and buffer */
1714         dev->req = usb_ep_alloc_request (gadget->ep0, GFP_KERNEL);
1715         if (!dev->req)
1716                 goto enomem;
1717         dev->req->context = NULL;
1718         dev->req->complete = epio_complete;
1719
1720         if (activate_ep_files (dev) < 0)
1721                 goto enomem;
1722
1723         INFO (dev, "bound to %s driver\n", gadget->name);
1724         spin_lock_irq(&dev->lock);
1725         dev->state = STATE_DEV_UNCONNECTED;
1726         spin_unlock_irq(&dev->lock);
1727         get_dev (dev);
1728         return 0;
1729
1730 enomem:
1731         gadgetfs_unbind (gadget);
1732         return -ENOMEM;
1733 }
1734
1735 static void
1736 gadgetfs_disconnect (struct usb_gadget *gadget)
1737 {
1738         struct dev_data         *dev = get_gadget_data (gadget);
1739
1740         spin_lock (&dev->lock);
1741         if (dev->state == STATE_DEV_UNCONNECTED)
1742                 goto exit;
1743         dev->state = STATE_DEV_UNCONNECTED;
1744
1745         INFO (dev, "disconnected\n");
1746         next_event (dev, GADGETFS_DISCONNECT);
1747         ep0_readable (dev);
1748 exit:
1749         spin_unlock (&dev->lock);
1750 }
1751
1752 static void
1753 gadgetfs_suspend (struct usb_gadget *gadget)
1754 {
1755         struct dev_data         *dev = get_gadget_data (gadget);
1756
1757         INFO (dev, "suspended from state %d\n", dev->state);
1758         spin_lock (&dev->lock);
1759         switch (dev->state) {
1760         case STATE_DEV_SETUP:           // VERY odd... host died??
1761         case STATE_DEV_CONNECTED:
1762         case STATE_DEV_UNCONNECTED:
1763                 next_event (dev, GADGETFS_SUSPEND);
1764                 ep0_readable (dev);
1765                 /* FALLTHROUGH */
1766         default:
1767                 break;
1768         }
1769         spin_unlock (&dev->lock);
1770 }
1771
1772 static struct usb_gadget_driver gadgetfs_driver = {
1773 #ifdef  CONFIG_USB_GADGET_DUALSPEED
1774         .speed          = USB_SPEED_HIGH,
1775 #else
1776         .speed          = USB_SPEED_FULL,
1777 #endif
1778         .function       = (char *) driver_desc,
1779         .unbind         = gadgetfs_unbind,
1780         .setup          = gadgetfs_setup,
1781         .disconnect     = gadgetfs_disconnect,
1782         .suspend        = gadgetfs_suspend,
1783
1784         .driver = {
1785                 .name           = (char *) shortname,
1786         },
1787 };
1788
1789 /*----------------------------------------------------------------------*/
1790
1791 static void gadgetfs_nop(struct usb_gadget *arg) { }
1792
1793 static int gadgetfs_probe (struct usb_gadget *gadget)
1794 {
1795         CHIP = gadget->name;
1796         return -EISNAM;
1797 }
1798
1799 static struct usb_gadget_driver probe_driver = {
1800         .speed          = USB_SPEED_HIGH,
1801         .unbind         = gadgetfs_nop,
1802         .setup          = (void *)gadgetfs_nop,
1803         .disconnect     = gadgetfs_nop,
1804         .driver = {
1805                 .name           = "nop",
1806         },
1807 };
1808
1809
1810 /* DEVICE INITIALIZATION
1811  *
1812  *     fd = open ("/dev/gadget/$CHIP", O_RDWR)
1813  *     status = write (fd, descriptors, sizeof descriptors)
1814  *
1815  * That write establishes the device configuration, so the kernel can
1816  * bind to the controller ... guaranteeing it can handle enumeration
1817  * at all necessary speeds.  Descriptor order is:
1818  *
1819  * . message tag (u32, host order) ... for now, must be zero; it
1820  *      would change to support features like multi-config devices
1821  * . full/low speed config ... all wTotalLength bytes (with interface,
1822  *      class, altsetting, endpoint, and other descriptors)
1823  * . high speed config ... all descriptors, for high speed operation;
1824  *      this one's optional except for high-speed hardware
1825  * . device descriptor
1826  *
1827  * Endpoints are not yet enabled. Drivers must wait until device
1828  * configuration and interface altsetting changes create
1829  * the need to configure (or unconfigure) them.
1830  *
1831  * After initialization, the device stays active for as long as that
1832  * $CHIP file is open.  Events must then be read from that descriptor,
1833  * such as configuration notifications.
1834  */
1835
1836 static int is_valid_config (struct usb_config_descriptor *config)
1837 {
1838         return config->bDescriptorType == USB_DT_CONFIG
1839                 && config->bLength == USB_DT_CONFIG_SIZE
1840                 && config->bConfigurationValue != 0
1841                 && (config->bmAttributes & USB_CONFIG_ATT_ONE) != 0
1842                 && (config->bmAttributes & USB_CONFIG_ATT_WAKEUP) == 0;
1843         /* FIXME if gadget->is_otg, _must_ include an otg descriptor */
1844         /* FIXME check lengths: walk to end */
1845 }
1846
1847 static ssize_t
1848 dev_config (struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
1849 {
1850         struct dev_data         *dev = fd->private_data;
1851         ssize_t                 value = len, length = len;
1852         unsigned                total;
1853         u32                     tag;
1854         char                    *kbuf;
1855
1856         if (len < (USB_DT_CONFIG_SIZE + USB_DT_DEVICE_SIZE + 4))
1857                 return -EINVAL;
1858
1859         /* we might need to change message format someday */
1860         if (copy_from_user (&tag, buf, 4))
1861                 return -EFAULT;
1862         if (tag != 0)
1863                 return -EINVAL;
1864         buf += 4;
1865         length -= 4;
1866
1867         kbuf = memdup_user(buf, length);
1868         if (IS_ERR(kbuf))
1869                 return PTR_ERR(kbuf);
1870
1871         spin_lock_irq (&dev->lock);
1872         value = -EINVAL;
1873         if (dev->buf)
1874                 goto fail;
1875         dev->buf = kbuf;
1876
1877         /* full or low speed config */
1878         dev->config = (void *) kbuf;
1879         total = le16_to_cpu(dev->config->wTotalLength);
1880         if (!is_valid_config (dev->config) || total >= length)
1881                 goto fail;
1882         kbuf += total;
1883         length -= total;
1884
1885         /* optional high speed config */
1886         if (kbuf [1] == USB_DT_CONFIG) {
1887                 dev->hs_config = (void *) kbuf;
1888                 total = le16_to_cpu(dev->hs_config->wTotalLength);
1889                 if (!is_valid_config (dev->hs_config) || total >= length)
1890                         goto fail;
1891                 kbuf += total;
1892                 length -= total;
1893         }
1894
1895         /* could support multiple configs, using another encoding! */
1896
1897         /* device descriptor (tweaked for paranoia) */
1898         if (length != USB_DT_DEVICE_SIZE)
1899                 goto fail;
1900         dev->dev = (void *)kbuf;
1901         if (dev->dev->bLength != USB_DT_DEVICE_SIZE
1902                         || dev->dev->bDescriptorType != USB_DT_DEVICE
1903                         || dev->dev->bNumConfigurations != 1)
1904                 goto fail;
1905         dev->dev->bNumConfigurations = 1;
1906         dev->dev->bcdUSB = cpu_to_le16 (0x0200);
1907
1908         /* triggers gadgetfs_bind(); then we can enumerate. */
1909         spin_unlock_irq (&dev->lock);
1910         value = usb_gadget_probe_driver(&gadgetfs_driver, gadgetfs_bind);
1911         if (value != 0) {
1912                 kfree (dev->buf);
1913                 dev->buf = NULL;
1914         } else {
1915                 /* at this point "good" hardware has for the first time
1916                  * let the USB the host see us.  alternatively, if users
1917                  * unplug/replug that will clear all the error state.
1918                  *
1919                  * note:  everything running before here was guaranteed
1920                  * to choke driver model style diagnostics.  from here
1921                  * on, they can work ... except in cleanup paths that
1922                  * kick in after the ep0 descriptor is closed.
1923                  */
1924                 fd->f_op = &ep0_io_operations;
1925                 value = len;
1926         }
1927         return value;
1928
1929 fail:
1930         spin_unlock_irq (&dev->lock);
1931         pr_debug ("%s: %s fail %Zd, %p\n", shortname, __func__, value, dev);
1932         kfree (dev->buf);
1933         dev->buf = NULL;
1934         return value;
1935 }
1936
1937 static int
1938 dev_open (struct inode *inode, struct file *fd)
1939 {
1940         struct dev_data         *dev = inode->i_private;
1941         int                     value = -EBUSY;
1942
1943         spin_lock_irq(&dev->lock);
1944         if (dev->state == STATE_DEV_DISABLED) {
1945                 dev->ev_next = 0;
1946                 dev->state = STATE_DEV_OPENED;
1947                 fd->private_data = dev;
1948                 get_dev (dev);
1949                 value = 0;
1950         }
1951         spin_unlock_irq(&dev->lock);
1952         return value;
1953 }
1954
1955 static const struct file_operations dev_init_operations = {
1956         .owner =        THIS_MODULE,
1957         .llseek =       no_llseek,
1958
1959         .open =         dev_open,
1960         .write =        dev_config,
1961         .fasync =       ep0_fasync,
1962         .unlocked_ioctl = dev_ioctl,
1963         .release =      dev_release,
1964 };
1965
1966 /*----------------------------------------------------------------------*/
1967
1968 /* FILESYSTEM AND SUPERBLOCK OPERATIONS
1969  *
1970  * Mounting the filesystem creates a controller file, used first for
1971  * device configuration then later for event monitoring.
1972  */
1973
1974
1975 /* FIXME PAM etc could set this security policy without mount options
1976  * if epfiles inherited ownership and permissons from ep0 ...
1977  */
1978
1979 static unsigned default_uid;
1980 static unsigned default_gid;
1981 static unsigned default_perm = S_IRUSR | S_IWUSR;
1982
1983 module_param (default_uid, uint, 0644);
1984 module_param (default_gid, uint, 0644);
1985 module_param (default_perm, uint, 0644);
1986
1987
1988 static struct inode *
1989 gadgetfs_make_inode (struct super_block *sb,
1990                 void *data, const struct file_operations *fops,
1991                 int mode)
1992 {
1993         struct inode *inode = new_inode (sb);
1994
1995         if (inode) {
1996                 inode->i_ino = get_next_ino();
1997                 inode->i_mode = mode;
1998                 inode->i_uid = default_uid;
1999                 inode->i_gid = default_gid;
2000                 inode->i_atime = inode->i_mtime = inode->i_ctime
2001                                 = CURRENT_TIME;
2002                 inode->i_private = data;
2003                 inode->i_fop = fops;
2004         }
2005         return inode;
2006 }
2007
2008 /* creates in fs root directory, so non-renamable and non-linkable.
2009  * so inode and dentry are paired, until device reconfig.
2010  */
2011 static struct inode *
2012 gadgetfs_create_file (struct super_block *sb, char const *name,
2013                 void *data, const struct file_operations *fops,
2014                 struct dentry **dentry_p)
2015 {
2016         struct dentry   *dentry;
2017         struct inode    *inode;
2018
2019         dentry = d_alloc_name(sb->s_root, name);
2020         if (!dentry)
2021                 return NULL;
2022
2023         inode = gadgetfs_make_inode (sb, data, fops,
2024                         S_IFREG | (default_perm & S_IRWXUGO));
2025         if (!inode) {
2026                 dput(dentry);
2027                 return NULL;
2028         }
2029         d_add (dentry, inode);
2030         *dentry_p = dentry;
2031         return inode;
2032 }
2033
2034 static const struct super_operations gadget_fs_operations = {
2035         .statfs =       simple_statfs,
2036         .drop_inode =   generic_delete_inode,
2037 };
2038
2039 static int
2040 gadgetfs_fill_super (struct super_block *sb, void *opts, int silent)
2041 {
2042         struct inode    *inode;
2043         struct dentry   *d;
2044         struct dev_data *dev;
2045
2046         if (the_device)
2047                 return -ESRCH;
2048
2049         /* fake probe to determine $CHIP */
2050         (void) usb_gadget_probe_driver(&probe_driver, gadgetfs_probe);
2051         if (!CHIP)
2052                 return -ENODEV;
2053
2054         /* superblock */
2055         sb->s_blocksize = PAGE_CACHE_SIZE;
2056         sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
2057         sb->s_magic = GADGETFS_MAGIC;
2058         sb->s_op = &gadget_fs_operations;
2059         sb->s_time_gran = 1;
2060
2061         /* root inode */
2062         inode = gadgetfs_make_inode (sb,
2063                         NULL, &simple_dir_operations,
2064                         S_IFDIR | S_IRUGO | S_IXUGO);
2065         if (!inode)
2066                 goto enomem0;
2067         inode->i_op = &simple_dir_inode_operations;
2068         if (!(d = d_alloc_root (inode)))
2069                 goto enomem1;
2070         sb->s_root = d;
2071
2072         /* the ep0 file is named after the controller we expect;
2073          * user mode code can use it for sanity checks, like we do.
2074          */
2075         dev = dev_new ();
2076         if (!dev)
2077                 goto enomem2;
2078
2079         dev->sb = sb;
2080         if (!gadgetfs_create_file (sb, CHIP,
2081                                 dev, &dev_init_operations,
2082                                 &dev->dentry))
2083                 goto enomem3;
2084
2085         /* other endpoint files are available after hardware setup,
2086          * from binding to a controller.
2087          */
2088         the_device = dev;
2089         return 0;
2090
2091 enomem3:
2092         put_dev (dev);
2093 enomem2:
2094         dput (d);
2095 enomem1:
2096         iput (inode);
2097 enomem0:
2098         return -ENOMEM;
2099 }
2100
2101 /* "mount -t gadgetfs path /dev/gadget" ends up here */
2102 static struct dentry *
2103 gadgetfs_mount (struct file_system_type *t, int flags,
2104                 const char *path, void *opts)
2105 {
2106         return mount_single (t, flags, opts, gadgetfs_fill_super);
2107 }
2108
2109 static void
2110 gadgetfs_kill_sb (struct super_block *sb)
2111 {
2112         kill_litter_super (sb);
2113         if (the_device) {
2114                 put_dev (the_device);
2115                 the_device = NULL;
2116         }
2117 }
2118
2119 /*----------------------------------------------------------------------*/
2120
2121 static struct file_system_type gadgetfs_type = {
2122         .owner          = THIS_MODULE,
2123         .name           = shortname,
2124         .mount          = gadgetfs_mount,
2125         .kill_sb        = gadgetfs_kill_sb,
2126 };
2127
2128 /*----------------------------------------------------------------------*/
2129
2130 static int __init init (void)
2131 {
2132         int status;
2133
2134         status = register_filesystem (&gadgetfs_type);
2135         if (status == 0)
2136                 pr_info ("%s: %s, version " DRIVER_VERSION "\n",
2137                         shortname, driver_desc);
2138         return status;
2139 }
2140 module_init (init);
2141
2142 static void __exit cleanup (void)
2143 {
2144         pr_debug ("unregister %s\n", shortname);
2145         unregister_filesystem (&gadgetfs_type);
2146 }
2147 module_exit (cleanup);
2148