switch open-coded instances of d_make_root() to new helper
[linux-2.6.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
13
14 /* #define VERBOSE_DEBUG */
15
16 #include <linux/init.h>
17 #include <linux/module.h>
18 #include <linux/fs.h>
19 #include <linux/pagemap.h>
20 #include <linux/uts.h>
21 #include <linux/wait.h>
22 #include <linux/compiler.h>
23 #include <asm/uaccess.h>
24 #include <linux/sched.h>
25 #include <linux/slab.h>
26 #include <linux/poll.h>
27
28 #include <linux/device.h>
29 #include <linux/moduleparam.h>
30
31 #include <linux/usb/gadgetfs.h>
32 #include <linux/usb/gadget.h>
33
34
35 /*
36  * The gadgetfs API maps each endpoint to a file descriptor so that you
37  * can use standard synchronous read/write calls for I/O.  There's some
38  * O_NONBLOCK and O_ASYNC/FASYNC style i/o support.  Example usermode
39  * drivers show how this works in practice.  You can also use AIO to
40  * eliminate I/O gaps between requests, to help when streaming data.
41  *
42  * Key parts that must be USB-specific are protocols defining how the
43  * read/write operations relate to the hardware state machines.  There
44  * are two types of files.  One type is for the device, implementing ep0.
45  * The other type is for each IN or OUT endpoint.  In both cases, the
46  * user mode driver must configure the hardware before using it.
47  *
48  * - First, dev_config() is called when /dev/gadget/$CHIP is configured
49  *   (by writing configuration and device descriptors).  Afterwards it
50  *   may serve as a source of device events, used to handle all control
51  *   requests other than basic enumeration.
52  *
53  * - Then, after a SET_CONFIGURATION control request, ep_config() is
54  *   called when each /dev/gadget/ep* file is configured (by writing
55  *   endpoint descriptors).  Afterwards these files are used to write()
56  *   IN data or to read() OUT data.  To halt the endpoint, a "wrong
57  *   direction" request is issued (like reading an IN endpoint).
58  *
59  * Unlike "usbfs" the only ioctl()s are for things that are rare, and maybe
60  * not possible on all hardware.  For example, precise fault handling with
61  * respect to data left in endpoint fifos after aborted operations; or
62  * selective clearing of endpoint halts, to implement SET_INTERFACE.
63  */
64
65 #define DRIVER_DESC     "USB Gadget filesystem"
66 #define DRIVER_VERSION  "24 Aug 2004"
67
68 static const char driver_desc [] = DRIVER_DESC;
69 static const char shortname [] = "gadgetfs";
70
71 MODULE_DESCRIPTION (DRIVER_DESC);
72 MODULE_AUTHOR ("David Brownell");
73 MODULE_LICENSE ("GPL");
74
75
76 /*----------------------------------------------------------------------*/
77
78 #define GADGETFS_MAGIC          0xaee71ee7
79 #define DMA_ADDR_INVALID        (~(dma_addr_t)0)
80
81 /* /dev/gadget/$CHIP represents ep0 and the whole device */
82 enum ep0_state {
83         /* DISBLED is the initial state.
84          */
85         STATE_DEV_DISABLED = 0,
86
87         /* Only one open() of /dev/gadget/$CHIP; only one file tracks
88          * ep0/device i/o modes and binding to the controller.  Driver
89          * must always write descriptors to initialize the device, then
90          * the device becomes UNCONNECTED until enumeration.
91          */
92         STATE_DEV_OPENED,
93
94         /* From then on, ep0 fd is in either of two basic modes:
95          * - (UN)CONNECTED: read usb_gadgetfs_event(s) from it
96          * - SETUP: read/write will transfer control data and succeed;
97          *   or if "wrong direction", performs protocol stall
98          */
99         STATE_DEV_UNCONNECTED,
100         STATE_DEV_CONNECTED,
101         STATE_DEV_SETUP,
102
103         /* UNBOUND means the driver closed ep0, so the device won't be
104          * accessible again (DEV_DISABLED) until all fds are closed.
105          */
106         STATE_DEV_UNBOUND,
107 };
108
109 /* enough for the whole queue: most events invalidate others */
110 #define N_EVENT                 5
111
112 struct dev_data {
113         spinlock_t                      lock;
114         atomic_t                        count;
115         enum ep0_state                  state;          /* P: lock */
116         struct usb_gadgetfs_event       event [N_EVENT];
117         unsigned                        ev_next;
118         struct fasync_struct            *fasync;
119         u8                              current_config;
120
121         /* drivers reading ep0 MUST handle control requests (SETUP)
122          * reported that way; else the host will time out.
123          */
124         unsigned                        usermode_setup : 1,
125                                         setup_in : 1,
126                                         setup_can_stall : 1,
127                                         setup_out_ready : 1,
128                                         setup_out_error : 1,
129                                         setup_abort : 1;
130         unsigned                        setup_wLength;
131
132         /* the rest is basically write-once */
133         struct usb_config_descriptor    *config, *hs_config;
134         struct usb_device_descriptor    *dev;
135         struct usb_request              *req;
136         struct usb_gadget               *gadget;
137         struct list_head                epfiles;
138         void                            *buf;
139         wait_queue_head_t               wait;
140         struct super_block              *sb;
141         struct dentry                   *dentry;
142
143         /* except this scratch i/o buffer for ep0 */
144         u8                              rbuf [256];
145 };
146
147 static inline void get_dev (struct dev_data *data)
148 {
149         atomic_inc (&data->count);
150 }
151
152 static void put_dev (struct dev_data *data)
153 {
154         if (likely (!atomic_dec_and_test (&data->count)))
155                 return;
156         /* needs no more cleanup */
157         BUG_ON (waitqueue_active (&data->wait));
158         kfree (data);
159 }
160
161 static struct dev_data *dev_new (void)
162 {
163         struct dev_data         *dev;
164
165         dev = kzalloc(sizeof(*dev), GFP_KERNEL);
166         if (!dev)
167                 return NULL;
168         dev->state = STATE_DEV_DISABLED;
169         atomic_set (&dev->count, 1);
170         spin_lock_init (&dev->lock);
171         INIT_LIST_HEAD (&dev->epfiles);
172         init_waitqueue_head (&dev->wait);
173         return dev;
174 }
175
176 /*----------------------------------------------------------------------*/
177
178 /* other /dev/gadget/$ENDPOINT files represent endpoints */
179 enum ep_state {
180         STATE_EP_DISABLED = 0,
181         STATE_EP_READY,
182         STATE_EP_ENABLED,
183         STATE_EP_UNBOUND,
184 };
185
186 struct ep_data {
187         struct mutex                    lock;
188         enum ep_state                   state;
189         atomic_t                        count;
190         struct dev_data                 *dev;
191         /* must hold dev->lock before accessing ep or req */
192         struct usb_ep                   *ep;
193         struct usb_request              *req;
194         ssize_t                         status;
195         char                            name [16];
196         struct usb_endpoint_descriptor  desc, hs_desc;
197         struct list_head                epfiles;
198         wait_queue_head_t               wait;
199         struct dentry                   *dentry;
200         struct inode                    *inode;
201 };
202
203 static inline void get_ep (struct ep_data *data)
204 {
205         atomic_inc (&data->count);
206 }
207
208 static void put_ep (struct ep_data *data)
209 {
210         if (likely (!atomic_dec_and_test (&data->count)))
211                 return;
212         put_dev (data->dev);
213         /* needs no more cleanup */
214         BUG_ON (!list_empty (&data->epfiles));
215         BUG_ON (waitqueue_active (&data->wait));
216         kfree (data);
217 }
218
219 /*----------------------------------------------------------------------*/
220
221 /* most "how to use the hardware" policy choices are in userspace:
222  * mapping endpoint roles (which the driver needs) to the capabilities
223  * which the usb controller has.  most of those capabilities are exposed
224  * implicitly, starting with the driver name and then endpoint names.
225  */
226
227 static const char *CHIP;
228
229 /*----------------------------------------------------------------------*/
230
231 /* NOTE:  don't use dev_printk calls before binding to the gadget
232  * at the end of ep0 configuration, or after unbind.
233  */
234
235 /* too wordy: dev_printk(level , &(d)->gadget->dev , fmt , ## args) */
236 #define xprintk(d,level,fmt,args...) \
237         printk(level "%s: " fmt , shortname , ## args)
238
239 #ifdef DEBUG
240 #define DBG(dev,fmt,args...) \
241         xprintk(dev , KERN_DEBUG , fmt , ## args)
242 #else
243 #define DBG(dev,fmt,args...) \
244         do { } while (0)
245 #endif /* DEBUG */
246
247 #ifdef VERBOSE_DEBUG
248 #define VDEBUG  DBG
249 #else
250 #define VDEBUG(dev,fmt,args...) \
251         do { } while (0)
252 #endif /* DEBUG */
253
254 #define ERROR(dev,fmt,args...) \
255         xprintk(dev , KERN_ERR , fmt , ## args)
256 #define INFO(dev,fmt,args...) \
257         xprintk(dev , KERN_INFO , fmt , ## args)
258
259
260 /*----------------------------------------------------------------------*/
261
262 /* SYNCHRONOUS ENDPOINT OPERATIONS (bulk/intr/iso)
263  *
264  * After opening, configure non-control endpoints.  Then use normal
265  * stream read() and write() requests; and maybe ioctl() to get more
266  * precise FIFO status when recovering from cancellation.
267  */
268
269 static void epio_complete (struct usb_ep *ep, struct usb_request *req)
270 {
271         struct ep_data  *epdata = ep->driver_data;
272
273         if (!req->context)
274                 return;
275         if (req->status)
276                 epdata->status = req->status;
277         else
278                 epdata->status = req->actual;
279         complete ((struct completion *)req->context);
280 }
281
282 /* tasklock endpoint, returning when it's connected.
283  * still need dev->lock to use epdata->ep.
284  */
285 static int
286 get_ready_ep (unsigned f_flags, struct ep_data *epdata)
287 {
288         int     val;
289
290         if (f_flags & O_NONBLOCK) {
291                 if (!mutex_trylock(&epdata->lock))
292                         goto nonblock;
293                 if (epdata->state != STATE_EP_ENABLED) {
294                         mutex_unlock(&epdata->lock);
295 nonblock:
296                         val = -EAGAIN;
297                 } else
298                         val = 0;
299                 return val;
300         }
301
302         val = mutex_lock_interruptible(&epdata->lock);
303         if (val < 0)
304                 return val;
305
306         switch (epdata->state) {
307         case STATE_EP_ENABLED:
308                 break;
309         // case STATE_EP_DISABLED:              /* "can't happen" */
310         // case STATE_EP_READY:                 /* "can't happen" */
311         default:                                /* error! */
312                 pr_debug ("%s: ep %p not available, state %d\n",
313                                 shortname, epdata, epdata->state);
314                 // FALLTHROUGH
315         case STATE_EP_UNBOUND:                  /* clean disconnect */
316                 val = -ENODEV;
317                 mutex_unlock(&epdata->lock);
318         }
319         return val;
320 }
321
322 static ssize_t
323 ep_io (struct ep_data *epdata, void *buf, unsigned len)
324 {
325         DECLARE_COMPLETION_ONSTACK (done);
326         int value;
327
328         spin_lock_irq (&epdata->dev->lock);
329         if (likely (epdata->ep != NULL)) {
330                 struct usb_request      *req = epdata->req;
331
332                 req->context = &done;
333                 req->complete = epio_complete;
334                 req->buf = buf;
335                 req->length = len;
336                 value = usb_ep_queue (epdata->ep, req, GFP_ATOMIC);
337         } else
338                 value = -ENODEV;
339         spin_unlock_irq (&epdata->dev->lock);
340
341         if (likely (value == 0)) {
342                 value = wait_event_interruptible (done.wait, done.done);
343                 if (value != 0) {
344                         spin_lock_irq (&epdata->dev->lock);
345                         if (likely (epdata->ep != NULL)) {
346                                 DBG (epdata->dev, "%s i/o interrupted\n",
347                                                 epdata->name);
348                                 usb_ep_dequeue (epdata->ep, epdata->req);
349                                 spin_unlock_irq (&epdata->dev->lock);
350
351                                 wait_event (done.wait, done.done);
352                                 if (epdata->status == -ECONNRESET)
353                                         epdata->status = -EINTR;
354                         } else {
355                                 spin_unlock_irq (&epdata->dev->lock);
356
357                                 DBG (epdata->dev, "endpoint gone\n");
358                                 epdata->status = -ENODEV;
359                         }
360                 }
361                 return epdata->status;
362         }
363         return value;
364 }
365
366
367 /* handle a synchronous OUT bulk/intr/iso transfer */
368 static ssize_t
369 ep_read (struct file *fd, char __user *buf, size_t len, loff_t *ptr)
370 {
371         struct ep_data          *data = fd->private_data;
372         void                    *kbuf;
373         ssize_t                 value;
374
375         if ((value = get_ready_ep (fd->f_flags, data)) < 0)
376                 return value;
377
378         /* halt any endpoint by doing a "wrong direction" i/o call */
379         if (usb_endpoint_dir_in(&data->desc)) {
380                 if (usb_endpoint_xfer_isoc(&data->desc)) {
381                         mutex_unlock(&data->lock);
382                         return -EINVAL;
383                 }
384                 DBG (data->dev, "%s halt\n", data->name);
385                 spin_lock_irq (&data->dev->lock);
386                 if (likely (data->ep != NULL))
387                         usb_ep_set_halt (data->ep);
388                 spin_unlock_irq (&data->dev->lock);
389                 mutex_unlock(&data->lock);
390                 return -EBADMSG;
391         }
392
393         /* FIXME readahead for O_NONBLOCK and poll(); careful with ZLPs */
394
395         value = -ENOMEM;
396         kbuf = kmalloc (len, GFP_KERNEL);
397         if (unlikely (!kbuf))
398                 goto free1;
399
400         value = ep_io (data, kbuf, len);
401         VDEBUG (data->dev, "%s read %zu OUT, status %d\n",
402                 data->name, len, (int) value);
403         if (value >= 0 && copy_to_user (buf, kbuf, value))
404                 value = -EFAULT;
405
406 free1:
407         mutex_unlock(&data->lock);
408         kfree (kbuf);
409         return value;
410 }
411
412 /* handle a synchronous IN bulk/intr/iso transfer */
413 static ssize_t
414 ep_write (struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
415 {
416         struct ep_data          *data = fd->private_data;
417         void                    *kbuf;
418         ssize_t                 value;
419
420         if ((value = get_ready_ep (fd->f_flags, data)) < 0)
421                 return value;
422
423         /* halt any endpoint by doing a "wrong direction" i/o call */
424         if (!usb_endpoint_dir_in(&data->desc)) {
425                 if (usb_endpoint_xfer_isoc(&data->desc)) {
426                         mutex_unlock(&data->lock);
427                         return -EINVAL;
428                 }
429                 DBG (data->dev, "%s halt\n", data->name);
430                 spin_lock_irq (&data->dev->lock);
431                 if (likely (data->ep != NULL))
432                         usb_ep_set_halt (data->ep);
433                 spin_unlock_irq (&data->dev->lock);
434                 mutex_unlock(&data->lock);
435                 return -EBADMSG;
436         }
437
438         /* FIXME writebehind for O_NONBLOCK and poll(), qlen = 1 */
439
440         value = -ENOMEM;
441         kbuf = kmalloc (len, GFP_KERNEL);
442         if (!kbuf)
443                 goto free1;
444         if (copy_from_user (kbuf, buf, len)) {
445                 value = -EFAULT;
446                 goto free1;
447         }
448
449         value = ep_io (data, kbuf, len);
450         VDEBUG (data->dev, "%s write %zu IN, status %d\n",
451                 data->name, len, (int) value);
452 free1:
453         mutex_unlock(&data->lock);
454         kfree (kbuf);
455         return value;
456 }
457
458 static int
459 ep_release (struct inode *inode, struct file *fd)
460 {
461         struct ep_data          *data = fd->private_data;
462         int value;
463
464         value = mutex_lock_interruptible(&data->lock);
465         if (value < 0)
466                 return value;
467
468         /* clean up if this can be reopened */
469         if (data->state != STATE_EP_UNBOUND) {
470                 data->state = STATE_EP_DISABLED;
471                 data->desc.bDescriptorType = 0;
472                 data->hs_desc.bDescriptorType = 0;
473                 usb_ep_disable(data->ep);
474         }
475         mutex_unlock(&data->lock);
476         put_ep (data);
477         return 0;
478 }
479
480 static long ep_ioctl(struct file *fd, unsigned code, unsigned long value)
481 {
482         struct ep_data          *data = fd->private_data;
483         int                     status;
484
485         if ((status = get_ready_ep (fd->f_flags, data)) < 0)
486                 return status;
487
488         spin_lock_irq (&data->dev->lock);
489         if (likely (data->ep != NULL)) {
490                 switch (code) {
491                 case GADGETFS_FIFO_STATUS:
492                         status = usb_ep_fifo_status (data->ep);
493                         break;
494                 case GADGETFS_FIFO_FLUSH:
495                         usb_ep_fifo_flush (data->ep);
496                         break;
497                 case GADGETFS_CLEAR_HALT:
498                         status = usb_ep_clear_halt (data->ep);
499                         break;
500                 default:
501                         status = -ENOTTY;
502                 }
503         } else
504                 status = -ENODEV;
505         spin_unlock_irq (&data->dev->lock);
506         mutex_unlock(&data->lock);
507         return status;
508 }
509
510 /*----------------------------------------------------------------------*/
511
512 /* ASYNCHRONOUS ENDPOINT I/O OPERATIONS (bulk/intr/iso) */
513
514 struct kiocb_priv {
515         struct usb_request      *req;
516         struct ep_data          *epdata;
517         void                    *buf;
518         const struct iovec      *iv;
519         unsigned long           nr_segs;
520         unsigned                actual;
521 };
522
523 static int ep_aio_cancel(struct kiocb *iocb, struct io_event *e)
524 {
525         struct kiocb_priv       *priv = iocb->private;
526         struct ep_data          *epdata;
527         int                     value;
528
529         local_irq_disable();
530         epdata = priv->epdata;
531         // spin_lock(&epdata->dev->lock);
532         kiocbSetCancelled(iocb);
533         if (likely(epdata && epdata->ep && priv->req))
534                 value = usb_ep_dequeue (epdata->ep, priv->req);
535         else
536                 value = -EINVAL;
537         // spin_unlock(&epdata->dev->lock);
538         local_irq_enable();
539
540         aio_put_req(iocb);
541         return value;
542 }
543
544 static ssize_t ep_aio_read_retry(struct kiocb *iocb)
545 {
546         struct kiocb_priv       *priv = iocb->private;
547         ssize_t                 len, total;
548         void                    *to_copy;
549         int                     i;
550
551         /* we "retry" to get the right mm context for this: */
552
553         /* copy stuff into user buffers */
554         total = priv->actual;
555         len = 0;
556         to_copy = priv->buf;
557         for (i=0; i < priv->nr_segs; i++) {
558                 ssize_t this = min((ssize_t)(priv->iv[i].iov_len), total);
559
560                 if (copy_to_user(priv->iv[i].iov_base, to_copy, this)) {
561                         if (len == 0)
562                                 len = -EFAULT;
563                         break;
564                 }
565
566                 total -= this;
567                 len += this;
568                 to_copy += this;
569                 if (total == 0)
570                         break;
571         }
572         kfree(priv->buf);
573         kfree(priv);
574         return len;
575 }
576
577 static void ep_aio_complete(struct usb_ep *ep, struct usb_request *req)
578 {
579         struct kiocb            *iocb = req->context;
580         struct kiocb_priv       *priv = iocb->private;
581         struct ep_data          *epdata = priv->epdata;
582
583         /* lock against disconnect (and ideally, cancel) */
584         spin_lock(&epdata->dev->lock);
585         priv->req = NULL;
586         priv->epdata = NULL;
587
588         /* if this was a write or a read returning no data then we
589          * don't need to copy anything to userspace, so we can
590          * complete the aio request immediately.
591          */
592         if (priv->iv == NULL || unlikely(req->actual == 0)) {
593                 kfree(req->buf);
594                 kfree(priv);
595                 iocb->private = NULL;
596                 /* aio_complete() reports bytes-transferred _and_ faults */
597                 aio_complete(iocb, req->actual ? req->actual : req->status,
598                                 req->status);
599         } else {
600                 /* retry() won't report both; so we hide some faults */
601                 if (unlikely(0 != req->status))
602                         DBG(epdata->dev, "%s fault %d len %d\n",
603                                 ep->name, req->status, req->actual);
604
605                 priv->buf = req->buf;
606                 priv->actual = req->actual;
607                 kick_iocb(iocb);
608         }
609         spin_unlock(&epdata->dev->lock);
610
611         usb_ep_free_request(ep, req);
612         put_ep(epdata);
613 }
614
615 static ssize_t
616 ep_aio_rwtail(
617         struct kiocb    *iocb,
618         char            *buf,
619         size_t          len,
620         struct ep_data  *epdata,
621         const struct iovec *iv,
622         unsigned long   nr_segs
623 )
624 {
625         struct kiocb_priv       *priv;
626         struct usb_request      *req;
627         ssize_t                 value;
628
629         priv = kmalloc(sizeof *priv, GFP_KERNEL);
630         if (!priv) {
631                 value = -ENOMEM;
632 fail:
633                 kfree(buf);
634                 return value;
635         }
636         iocb->private = priv;
637         priv->iv = iv;
638         priv->nr_segs = nr_segs;
639
640         value = get_ready_ep(iocb->ki_filp->f_flags, epdata);
641         if (unlikely(value < 0)) {
642                 kfree(priv);
643                 goto fail;
644         }
645
646         iocb->ki_cancel = ep_aio_cancel;
647         get_ep(epdata);
648         priv->epdata = epdata;
649         priv->actual = 0;
650
651         /* each kiocb is coupled to one usb_request, but we can't
652          * allocate or submit those if the host disconnected.
653          */
654         spin_lock_irq(&epdata->dev->lock);
655         if (likely(epdata->ep)) {
656                 req = usb_ep_alloc_request(epdata->ep, GFP_ATOMIC);
657                 if (likely(req)) {
658                         priv->req = req;
659                         req->buf = buf;
660                         req->length = len;
661                         req->complete = ep_aio_complete;
662                         req->context = iocb;
663                         value = usb_ep_queue(epdata->ep, req, GFP_ATOMIC);
664                         if (unlikely(0 != value))
665                                 usb_ep_free_request(epdata->ep, req);
666                 } else
667                         value = -EAGAIN;
668         } else
669                 value = -ENODEV;
670         spin_unlock_irq(&epdata->dev->lock);
671
672         mutex_unlock(&epdata->lock);
673
674         if (unlikely(value)) {
675                 kfree(priv);
676                 put_ep(epdata);
677         } else
678                 value = (iv ? -EIOCBRETRY : -EIOCBQUEUED);
679         return value;
680 }
681
682 static ssize_t
683 ep_aio_read(struct kiocb *iocb, const struct iovec *iov,
684                 unsigned long nr_segs, loff_t o)
685 {
686         struct ep_data          *epdata = iocb->ki_filp->private_data;
687         char                    *buf;
688
689         if (unlikely(usb_endpoint_dir_in(&epdata->desc)))
690                 return -EINVAL;
691
692         buf = kmalloc(iocb->ki_left, GFP_KERNEL);
693         if (unlikely(!buf))
694                 return -ENOMEM;
695
696         iocb->ki_retry = ep_aio_read_retry;
697         return ep_aio_rwtail(iocb, buf, iocb->ki_left, epdata, iov, nr_segs);
698 }
699
700 static ssize_t
701 ep_aio_write(struct kiocb *iocb, const struct iovec *iov,
702                 unsigned long nr_segs, loff_t o)
703 {
704         struct ep_data          *epdata = iocb->ki_filp->private_data;
705         char                    *buf;
706         size_t                  len = 0;
707         int                     i = 0;
708
709         if (unlikely(!usb_endpoint_dir_in(&epdata->desc)))
710                 return -EINVAL;
711
712         buf = kmalloc(iocb->ki_left, GFP_KERNEL);
713         if (unlikely(!buf))
714                 return -ENOMEM;
715
716         for (i=0; i < nr_segs; i++) {
717                 if (unlikely(copy_from_user(&buf[len], iov[i].iov_base,
718                                 iov[i].iov_len) != 0)) {
719                         kfree(buf);
720                         return -EFAULT;
721                 }
722                 len += iov[i].iov_len;
723         }
724         return ep_aio_rwtail(iocb, buf, len, epdata, NULL, 0);
725 }
726
727 /*----------------------------------------------------------------------*/
728
729 /* used after endpoint configuration */
730 static const struct file_operations ep_io_operations = {
731         .owner =        THIS_MODULE,
732         .llseek =       no_llseek,
733
734         .read =         ep_read,
735         .write =        ep_write,
736         .unlocked_ioctl = ep_ioctl,
737         .release =      ep_release,
738
739         .aio_read =     ep_aio_read,
740         .aio_write =    ep_aio_write,
741 };
742
743 /* ENDPOINT INITIALIZATION
744  *
745  *     fd = open ("/dev/gadget/$ENDPOINT", O_RDWR)
746  *     status = write (fd, descriptors, sizeof descriptors)
747  *
748  * That write establishes the endpoint configuration, configuring
749  * the controller to process bulk, interrupt, or isochronous transfers
750  * at the right maxpacket size, and so on.
751  *
752  * The descriptors are message type 1, identified by a host order u32
753  * at the beginning of what's written.  Descriptor order is: full/low
754  * speed descriptor, then optional high speed descriptor.
755  */
756 static ssize_t
757 ep_config (struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
758 {
759         struct ep_data          *data = fd->private_data;
760         struct usb_ep           *ep;
761         u32                     tag;
762         int                     value, length = len;
763
764         value = mutex_lock_interruptible(&data->lock);
765         if (value < 0)
766                 return value;
767
768         if (data->state != STATE_EP_READY) {
769                 value = -EL2HLT;
770                 goto fail;
771         }
772
773         value = len;
774         if (len < USB_DT_ENDPOINT_SIZE + 4)
775                 goto fail0;
776
777         /* we might need to change message format someday */
778         if (copy_from_user (&tag, buf, 4)) {
779                 goto fail1;
780         }
781         if (tag != 1) {
782                 DBG(data->dev, "config %s, bad tag %d\n", data->name, tag);
783                 goto fail0;
784         }
785         buf += 4;
786         len -= 4;
787
788         /* NOTE:  audio endpoint extensions not accepted here;
789          * just don't include the extra bytes.
790          */
791
792         /* full/low speed descriptor, then high speed */
793         if (copy_from_user (&data->desc, buf, USB_DT_ENDPOINT_SIZE)) {
794                 goto fail1;
795         }
796         if (data->desc.bLength != USB_DT_ENDPOINT_SIZE
797                         || data->desc.bDescriptorType != USB_DT_ENDPOINT)
798                 goto fail0;
799         if (len != USB_DT_ENDPOINT_SIZE) {
800                 if (len != 2 * USB_DT_ENDPOINT_SIZE)
801                         goto fail0;
802                 if (copy_from_user (&data->hs_desc, buf + USB_DT_ENDPOINT_SIZE,
803                                         USB_DT_ENDPOINT_SIZE)) {
804                         goto fail1;
805                 }
806                 if (data->hs_desc.bLength != USB_DT_ENDPOINT_SIZE
807                                 || data->hs_desc.bDescriptorType
808                                         != USB_DT_ENDPOINT) {
809                         DBG(data->dev, "config %s, bad hs length or type\n",
810                                         data->name);
811                         goto fail0;
812                 }
813         }
814
815         spin_lock_irq (&data->dev->lock);
816         if (data->dev->state == STATE_DEV_UNBOUND) {
817                 value = -ENOENT;
818                 goto gone;
819         } else if ((ep = data->ep) == NULL) {
820                 value = -ENODEV;
821                 goto gone;
822         }
823         switch (data->dev->gadget->speed) {
824         case USB_SPEED_LOW:
825         case USB_SPEED_FULL:
826                 ep->desc = &data->desc;
827                 value = usb_ep_enable(ep);
828                 if (value == 0)
829                         data->state = STATE_EP_ENABLED;
830                 break;
831 #ifdef  CONFIG_USB_GADGET_DUALSPEED
832         case USB_SPEED_HIGH:
833                 /* fails if caller didn't provide that descriptor... */
834                 ep->desc = &data->hs_desc;
835                 value = usb_ep_enable(ep);
836                 if (value == 0)
837                         data->state = STATE_EP_ENABLED;
838                 break;
839 #endif
840         default:
841                 DBG(data->dev, "unconnected, %s init abandoned\n",
842                                 data->name);
843                 value = -EINVAL;
844         }
845         if (value == 0) {
846                 fd->f_op = &ep_io_operations;
847                 value = length;
848         }
849 gone:
850         spin_unlock_irq (&data->dev->lock);
851         if (value < 0) {
852 fail:
853                 data->desc.bDescriptorType = 0;
854                 data->hs_desc.bDescriptorType = 0;
855         }
856         mutex_unlock(&data->lock);
857         return value;
858 fail0:
859         value = -EINVAL;
860         goto fail;
861 fail1:
862         value = -EFAULT;
863         goto fail;
864 }
865
866 static int
867 ep_open (struct inode *inode, struct file *fd)
868 {
869         struct ep_data          *data = inode->i_private;
870         int                     value = -EBUSY;
871
872         if (mutex_lock_interruptible(&data->lock) != 0)
873                 return -EINTR;
874         spin_lock_irq (&data->dev->lock);
875         if (data->dev->state == STATE_DEV_UNBOUND)
876                 value = -ENOENT;
877         else if (data->state == STATE_EP_DISABLED) {
878                 value = 0;
879                 data->state = STATE_EP_READY;
880                 get_ep (data);
881                 fd->private_data = data;
882                 VDEBUG (data->dev, "%s ready\n", data->name);
883         } else
884                 DBG (data->dev, "%s state %d\n",
885                         data->name, data->state);
886         spin_unlock_irq (&data->dev->lock);
887         mutex_unlock(&data->lock);
888         return value;
889 }
890
891 /* used before endpoint configuration */
892 static const struct file_operations ep_config_operations = {
893         .owner =        THIS_MODULE,
894         .llseek =       no_llseek,
895
896         .open =         ep_open,
897         .write =        ep_config,
898         .release =      ep_release,
899 };
900
901 /*----------------------------------------------------------------------*/
902
903 /* EP0 IMPLEMENTATION can be partly in userspace.
904  *
905  * Drivers that use this facility receive various events, including
906  * control requests the kernel doesn't handle.  Drivers that don't
907  * use this facility may be too simple-minded for real applications.
908  */
909
910 static inline void ep0_readable (struct dev_data *dev)
911 {
912         wake_up (&dev->wait);
913         kill_fasync (&dev->fasync, SIGIO, POLL_IN);
914 }
915
916 static void clean_req (struct usb_ep *ep, struct usb_request *req)
917 {
918         struct dev_data         *dev = ep->driver_data;
919
920         if (req->buf != dev->rbuf) {
921                 kfree(req->buf);
922                 req->buf = dev->rbuf;
923                 req->dma = DMA_ADDR_INVALID;
924         }
925         req->complete = epio_complete;
926         dev->setup_out_ready = 0;
927 }
928
929 static void ep0_complete (struct usb_ep *ep, struct usb_request *req)
930 {
931         struct dev_data         *dev = ep->driver_data;
932         unsigned long           flags;
933         int                     free = 1;
934
935         /* for control OUT, data must still get to userspace */
936         spin_lock_irqsave(&dev->lock, flags);
937         if (!dev->setup_in) {
938                 dev->setup_out_error = (req->status != 0);
939                 if (!dev->setup_out_error)
940                         free = 0;
941                 dev->setup_out_ready = 1;
942                 ep0_readable (dev);
943         }
944
945         /* clean up as appropriate */
946         if (free && req->buf != &dev->rbuf)
947                 clean_req (ep, req);
948         req->complete = epio_complete;
949         spin_unlock_irqrestore(&dev->lock, flags);
950 }
951
952 static int setup_req (struct usb_ep *ep, struct usb_request *req, u16 len)
953 {
954         struct dev_data *dev = ep->driver_data;
955
956         if (dev->setup_out_ready) {
957                 DBG (dev, "ep0 request busy!\n");
958                 return -EBUSY;
959         }
960         if (len > sizeof (dev->rbuf))
961                 req->buf = kmalloc(len, GFP_ATOMIC);
962         if (req->buf == NULL) {
963                 req->buf = dev->rbuf;
964                 return -ENOMEM;
965         }
966         req->complete = ep0_complete;
967         req->length = len;
968         req->zero = 0;
969         return 0;
970 }
971
972 static ssize_t
973 ep0_read (struct file *fd, char __user *buf, size_t len, loff_t *ptr)
974 {
975         struct dev_data                 *dev = fd->private_data;
976         ssize_t                         retval;
977         enum ep0_state                  state;
978
979         spin_lock_irq (&dev->lock);
980
981         /* report fd mode change before acting on it */
982         if (dev->setup_abort) {
983                 dev->setup_abort = 0;
984                 retval = -EIDRM;
985                 goto done;
986         }
987
988         /* control DATA stage */
989         if ((state = dev->state) == STATE_DEV_SETUP) {
990
991                 if (dev->setup_in) {            /* stall IN */
992                         VDEBUG(dev, "ep0in stall\n");
993                         (void) usb_ep_set_halt (dev->gadget->ep0);
994                         retval = -EL2HLT;
995                         dev->state = STATE_DEV_CONNECTED;
996
997                 } else if (len == 0) {          /* ack SET_CONFIGURATION etc */
998                         struct usb_ep           *ep = dev->gadget->ep0;
999                         struct usb_request      *req = dev->req;
1000
1001                         if ((retval = setup_req (ep, req, 0)) == 0)
1002                                 retval = usb_ep_queue (ep, req, GFP_ATOMIC);
1003                         dev->state = STATE_DEV_CONNECTED;
1004
1005                         /* assume that was SET_CONFIGURATION */
1006                         if (dev->current_config) {
1007                                 unsigned power;
1008
1009                                 if (gadget_is_dualspeed(dev->gadget)
1010                                                 && (dev->gadget->speed
1011                                                         == USB_SPEED_HIGH))
1012                                         power = dev->hs_config->bMaxPower;
1013                                 else
1014                                         power = dev->config->bMaxPower;
1015                                 usb_gadget_vbus_draw(dev->gadget, 2 * power);
1016                         }
1017
1018                 } else {                        /* collect OUT data */
1019                         if ((fd->f_flags & O_NONBLOCK) != 0
1020                                         && !dev->setup_out_ready) {
1021                                 retval = -EAGAIN;
1022                                 goto done;
1023                         }
1024                         spin_unlock_irq (&dev->lock);
1025                         retval = wait_event_interruptible (dev->wait,
1026                                         dev->setup_out_ready != 0);
1027
1028                         /* FIXME state could change from under us */
1029                         spin_lock_irq (&dev->lock);
1030                         if (retval)
1031                                 goto done;
1032
1033                         if (dev->state != STATE_DEV_SETUP) {
1034                                 retval = -ECANCELED;
1035                                 goto done;
1036                         }
1037                         dev->state = STATE_DEV_CONNECTED;
1038
1039                         if (dev->setup_out_error)
1040                                 retval = -EIO;
1041                         else {
1042                                 len = min (len, (size_t)dev->req->actual);
1043 // FIXME don't call this with the spinlock held ...
1044                                 if (copy_to_user (buf, dev->req->buf, len))
1045                                         retval = -EFAULT;
1046                                 clean_req (dev->gadget->ep0, dev->req);
1047                                 /* NOTE userspace can't yet choose to stall */
1048                         }
1049                 }
1050                 goto done;
1051         }
1052
1053         /* else normal: return event data */
1054         if (len < sizeof dev->event [0]) {
1055                 retval = -EINVAL;
1056                 goto done;
1057         }
1058         len -= len % sizeof (struct usb_gadgetfs_event);
1059         dev->usermode_setup = 1;
1060
1061 scan:
1062         /* return queued events right away */
1063         if (dev->ev_next != 0) {
1064                 unsigned                i, n;
1065
1066                 n = len / sizeof (struct usb_gadgetfs_event);
1067                 if (dev->ev_next < n)
1068                         n = dev->ev_next;
1069
1070                 /* ep0 i/o has special semantics during STATE_DEV_SETUP */
1071                 for (i = 0; i < n; i++) {
1072                         if (dev->event [i].type == GADGETFS_SETUP) {
1073                                 dev->state = STATE_DEV_SETUP;
1074                                 n = i + 1;
1075                                 break;
1076                         }
1077                 }
1078                 spin_unlock_irq (&dev->lock);
1079                 len = n * sizeof (struct usb_gadgetfs_event);
1080                 if (copy_to_user (buf, &dev->event, len))
1081                         retval = -EFAULT;
1082                 else
1083                         retval = len;
1084                 if (len > 0) {
1085                         /* NOTE this doesn't guard against broken drivers;
1086                          * concurrent ep0 readers may lose events.
1087                          */
1088                         spin_lock_irq (&dev->lock);
1089                         if (dev->ev_next > n) {
1090                                 memmove(&dev->event[0], &dev->event[n],
1091                                         sizeof (struct usb_gadgetfs_event)
1092                                                 * (dev->ev_next - n));
1093                         }
1094                         dev->ev_next -= n;
1095                         spin_unlock_irq (&dev->lock);
1096                 }
1097                 return retval;
1098         }
1099         if (fd->f_flags & O_NONBLOCK) {
1100                 retval = -EAGAIN;
1101                 goto done;
1102         }
1103
1104         switch (state) {
1105         default:
1106                 DBG (dev, "fail %s, state %d\n", __func__, state);
1107                 retval = -ESRCH;
1108                 break;
1109         case STATE_DEV_UNCONNECTED:
1110         case STATE_DEV_CONNECTED:
1111                 spin_unlock_irq (&dev->lock);
1112                 DBG (dev, "%s wait\n", __func__);
1113
1114                 /* wait for events */
1115                 retval = wait_event_interruptible (dev->wait,
1116                                 dev->ev_next != 0);
1117                 if (retval < 0)
1118                         return retval;
1119                 spin_lock_irq (&dev->lock);
1120                 goto scan;
1121         }
1122
1123 done:
1124         spin_unlock_irq (&dev->lock);
1125         return retval;
1126 }
1127
1128 static struct usb_gadgetfs_event *
1129 next_event (struct dev_data *dev, enum usb_gadgetfs_event_type type)
1130 {
1131         struct usb_gadgetfs_event       *event;
1132         unsigned                        i;
1133
1134         switch (type) {
1135         /* these events purge the queue */
1136         case GADGETFS_DISCONNECT:
1137                 if (dev->state == STATE_DEV_SETUP)
1138                         dev->setup_abort = 1;
1139                 // FALL THROUGH
1140         case GADGETFS_CONNECT:
1141                 dev->ev_next = 0;
1142                 break;
1143         case GADGETFS_SETUP:            /* previous request timed out */
1144         case GADGETFS_SUSPEND:          /* same effect */
1145                 /* these events can't be repeated */
1146                 for (i = 0; i != dev->ev_next; i++) {
1147                         if (dev->event [i].type != type)
1148                                 continue;
1149                         DBG(dev, "discard old event[%d] %d\n", i, type);
1150                         dev->ev_next--;
1151                         if (i == dev->ev_next)
1152                                 break;
1153                         /* indices start at zero, for simplicity */
1154                         memmove (&dev->event [i], &dev->event [i + 1],
1155                                 sizeof (struct usb_gadgetfs_event)
1156                                         * (dev->ev_next - i));
1157                 }
1158                 break;
1159         default:
1160                 BUG ();
1161         }
1162         VDEBUG(dev, "event[%d] = %d\n", dev->ev_next, type);
1163         event = &dev->event [dev->ev_next++];
1164         BUG_ON (dev->ev_next > N_EVENT);
1165         memset (event, 0, sizeof *event);
1166         event->type = type;
1167         return event;
1168 }
1169
1170 static ssize_t
1171 ep0_write (struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
1172 {
1173         struct dev_data         *dev = fd->private_data;
1174         ssize_t                 retval = -ESRCH;
1175
1176         spin_lock_irq (&dev->lock);
1177
1178         /* report fd mode change before acting on it */
1179         if (dev->setup_abort) {
1180                 dev->setup_abort = 0;
1181                 retval = -EIDRM;
1182
1183         /* data and/or status stage for control request */
1184         } else if (dev->state == STATE_DEV_SETUP) {
1185
1186                 /* IN DATA+STATUS caller makes len <= wLength */
1187                 if (dev->setup_in) {
1188                         retval = setup_req (dev->gadget->ep0, dev->req, len);
1189                         if (retval == 0) {
1190                                 dev->state = STATE_DEV_CONNECTED;
1191                                 spin_unlock_irq (&dev->lock);
1192                                 if (copy_from_user (dev->req->buf, buf, len))
1193                                         retval = -EFAULT;
1194                                 else {
1195                                         if (len < dev->setup_wLength)
1196                                                 dev->req->zero = 1;
1197                                         retval = usb_ep_queue (
1198                                                 dev->gadget->ep0, dev->req,
1199                                                 GFP_KERNEL);
1200                                 }
1201                                 if (retval < 0) {
1202                                         spin_lock_irq (&dev->lock);
1203                                         clean_req (dev->gadget->ep0, dev->req);
1204                                         spin_unlock_irq (&dev->lock);
1205                                 } else
1206                                         retval = len;
1207
1208                                 return retval;
1209                         }
1210
1211                 /* can stall some OUT transfers */
1212                 } else if (dev->setup_can_stall) {
1213                         VDEBUG(dev, "ep0out stall\n");
1214                         (void) usb_ep_set_halt (dev->gadget->ep0);
1215                         retval = -EL2HLT;
1216                         dev->state = STATE_DEV_CONNECTED;
1217                 } else {
1218                         DBG(dev, "bogus ep0out stall!\n");
1219                 }
1220         } else
1221                 DBG (dev, "fail %s, state %d\n", __func__, dev->state);
1222
1223         spin_unlock_irq (&dev->lock);
1224         return retval;
1225 }
1226
1227 static int
1228 ep0_fasync (int f, struct file *fd, int on)
1229 {
1230         struct dev_data         *dev = fd->private_data;
1231         // caller must F_SETOWN before signal delivery happens
1232         VDEBUG (dev, "%s %s\n", __func__, on ? "on" : "off");
1233         return fasync_helper (f, fd, on, &dev->fasync);
1234 }
1235
1236 static struct usb_gadget_driver gadgetfs_driver;
1237
1238 static int
1239 dev_release (struct inode *inode, struct file *fd)
1240 {
1241         struct dev_data         *dev = fd->private_data;
1242
1243         /* closing ep0 === shutdown all */
1244
1245         usb_gadget_unregister_driver (&gadgetfs_driver);
1246
1247         /* at this point "good" hardware has disconnected the
1248          * device from USB; the host won't see it any more.
1249          * alternatively, all host requests will time out.
1250          */
1251
1252         kfree (dev->buf);
1253         dev->buf = NULL;
1254         put_dev (dev);
1255
1256         /* other endpoints were all decoupled from this device */
1257         spin_lock_irq(&dev->lock);
1258         dev->state = STATE_DEV_DISABLED;
1259         spin_unlock_irq(&dev->lock);
1260         return 0;
1261 }
1262
1263 static unsigned int
1264 ep0_poll (struct file *fd, poll_table *wait)
1265 {
1266        struct dev_data         *dev = fd->private_data;
1267        int                     mask = 0;
1268
1269        poll_wait(fd, &dev->wait, wait);
1270
1271        spin_lock_irq (&dev->lock);
1272
1273        /* report fd mode change before acting on it */
1274        if (dev->setup_abort) {
1275                dev->setup_abort = 0;
1276                mask = POLLHUP;
1277                goto out;
1278        }
1279
1280        if (dev->state == STATE_DEV_SETUP) {
1281                if (dev->setup_in || dev->setup_can_stall)
1282                        mask = POLLOUT;
1283        } else {
1284                if (dev->ev_next != 0)
1285                        mask = POLLIN;
1286        }
1287 out:
1288        spin_unlock_irq(&dev->lock);
1289        return mask;
1290 }
1291
1292 static long dev_ioctl (struct file *fd, unsigned code, unsigned long value)
1293 {
1294         struct dev_data         *dev = fd->private_data;
1295         struct usb_gadget       *gadget = dev->gadget;
1296         long ret = -ENOTTY;
1297
1298         if (gadget->ops->ioctl)
1299                 ret = gadget->ops->ioctl (gadget, code, value);
1300
1301         return ret;
1302 }
1303
1304 /* used after device configuration */
1305 static const struct file_operations ep0_io_operations = {
1306         .owner =        THIS_MODULE,
1307         .llseek =       no_llseek,
1308
1309         .read =         ep0_read,
1310         .write =        ep0_write,
1311         .fasync =       ep0_fasync,
1312         .poll =         ep0_poll,
1313         .unlocked_ioctl =       dev_ioctl,
1314         .release =      dev_release,
1315 };
1316
1317 /*----------------------------------------------------------------------*/
1318
1319 /* The in-kernel gadget driver handles most ep0 issues, in particular
1320  * enumerating the single configuration (as provided from user space).
1321  *
1322  * Unrecognized ep0 requests may be handled in user space.
1323  */
1324
1325 #ifdef  CONFIG_USB_GADGET_DUALSPEED
1326 static void make_qualifier (struct dev_data *dev)
1327 {
1328         struct usb_qualifier_descriptor         qual;
1329         struct usb_device_descriptor            *desc;
1330
1331         qual.bLength = sizeof qual;
1332         qual.bDescriptorType = USB_DT_DEVICE_QUALIFIER;
1333         qual.bcdUSB = cpu_to_le16 (0x0200);
1334
1335         desc = dev->dev;
1336         qual.bDeviceClass = desc->bDeviceClass;
1337         qual.bDeviceSubClass = desc->bDeviceSubClass;
1338         qual.bDeviceProtocol = desc->bDeviceProtocol;
1339
1340         /* assumes ep0 uses the same value for both speeds ... */
1341         qual.bMaxPacketSize0 = dev->gadget->ep0->maxpacket;
1342
1343         qual.bNumConfigurations = 1;
1344         qual.bRESERVED = 0;
1345
1346         memcpy (dev->rbuf, &qual, sizeof qual);
1347 }
1348 #endif
1349
1350 static int
1351 config_buf (struct dev_data *dev, u8 type, unsigned index)
1352 {
1353         int             len;
1354         int             hs = 0;
1355
1356         /* only one configuration */
1357         if (index > 0)
1358                 return -EINVAL;
1359
1360         if (gadget_is_dualspeed(dev->gadget)) {
1361                 hs = (dev->gadget->speed == USB_SPEED_HIGH);
1362                 if (type == USB_DT_OTHER_SPEED_CONFIG)
1363                         hs = !hs;
1364         }
1365         if (hs) {
1366                 dev->req->buf = dev->hs_config;
1367                 len = le16_to_cpu(dev->hs_config->wTotalLength);
1368         } else {
1369                 dev->req->buf = dev->config;
1370                 len = le16_to_cpu(dev->config->wTotalLength);
1371         }
1372         ((u8 *)dev->req->buf) [1] = type;
1373         return len;
1374 }
1375
1376 static int
1377 gadgetfs_setup (struct usb_gadget *gadget, const struct usb_ctrlrequest *ctrl)
1378 {
1379         struct dev_data                 *dev = get_gadget_data (gadget);
1380         struct usb_request              *req = dev->req;
1381         int                             value = -EOPNOTSUPP;
1382         struct usb_gadgetfs_event       *event;
1383         u16                             w_value = le16_to_cpu(ctrl->wValue);
1384         u16                             w_length = le16_to_cpu(ctrl->wLength);
1385
1386         spin_lock (&dev->lock);
1387         dev->setup_abort = 0;
1388         if (dev->state == STATE_DEV_UNCONNECTED) {
1389                 if (gadget_is_dualspeed(gadget)
1390                                 && gadget->speed == USB_SPEED_HIGH
1391                                 && dev->hs_config == NULL) {
1392                         spin_unlock(&dev->lock);
1393                         ERROR (dev, "no high speed config??\n");
1394                         return -EINVAL;
1395                 }
1396
1397                 dev->state = STATE_DEV_CONNECTED;
1398
1399                 INFO (dev, "connected\n");
1400                 event = next_event (dev, GADGETFS_CONNECT);
1401                 event->u.speed = gadget->speed;
1402                 ep0_readable (dev);
1403
1404         /* host may have given up waiting for response.  we can miss control
1405          * requests handled lower down (device/endpoint status and features);
1406          * then ep0_{read,write} will report the wrong status. controller
1407          * driver will have aborted pending i/o.
1408          */
1409         } else if (dev->state == STATE_DEV_SETUP)
1410                 dev->setup_abort = 1;
1411
1412         req->buf = dev->rbuf;
1413         req->dma = DMA_ADDR_INVALID;
1414         req->context = NULL;
1415         value = -EOPNOTSUPP;
1416         switch (ctrl->bRequest) {
1417
1418         case USB_REQ_GET_DESCRIPTOR:
1419                 if (ctrl->bRequestType != USB_DIR_IN)
1420                         goto unrecognized;
1421                 switch (w_value >> 8) {
1422
1423                 case USB_DT_DEVICE:
1424                         value = min (w_length, (u16) sizeof *dev->dev);
1425                         dev->dev->bMaxPacketSize0 = dev->gadget->ep0->maxpacket;
1426                         req->buf = dev->dev;
1427                         break;
1428 #ifdef  CONFIG_USB_GADGET_DUALSPEED
1429                 case USB_DT_DEVICE_QUALIFIER:
1430                         if (!dev->hs_config)
1431                                 break;
1432                         value = min (w_length, (u16)
1433                                 sizeof (struct usb_qualifier_descriptor));
1434                         make_qualifier (dev);
1435                         break;
1436                 case USB_DT_OTHER_SPEED_CONFIG:
1437                         // FALLTHROUGH
1438 #endif
1439                 case USB_DT_CONFIG:
1440                         value = config_buf (dev,
1441                                         w_value >> 8,
1442                                         w_value & 0xff);
1443                         if (value >= 0)
1444                                 value = min (w_length, (u16) value);
1445                         break;
1446                 case USB_DT_STRING:
1447                         goto unrecognized;
1448
1449                 default:                // all others are errors
1450                         break;
1451                 }
1452                 break;
1453
1454         /* currently one config, two speeds */
1455         case USB_REQ_SET_CONFIGURATION:
1456                 if (ctrl->bRequestType != 0)
1457                         goto unrecognized;
1458                 if (0 == (u8) w_value) {
1459                         value = 0;
1460                         dev->current_config = 0;
1461                         usb_gadget_vbus_draw(gadget, 8 /* mA */ );
1462                         // user mode expected to disable endpoints
1463                 } else {
1464                         u8      config, power;
1465
1466                         if (gadget_is_dualspeed(gadget)
1467                                         && gadget->speed == USB_SPEED_HIGH) {
1468                                 config = dev->hs_config->bConfigurationValue;
1469                                 power = dev->hs_config->bMaxPower;
1470                         } else {
1471                                 config = dev->config->bConfigurationValue;
1472                                 power = dev->config->bMaxPower;
1473                         }
1474
1475                         if (config == (u8) w_value) {
1476                                 value = 0;
1477                                 dev->current_config = config;
1478                                 usb_gadget_vbus_draw(gadget, 2 * power);
1479                         }
1480                 }
1481
1482                 /* report SET_CONFIGURATION like any other control request,
1483                  * except that usermode may not stall this.  the next
1484                  * request mustn't be allowed start until this finishes:
1485                  * endpoints and threads set up, etc.
1486                  *
1487                  * NOTE:  older PXA hardware (before PXA 255: without UDCCFR)
1488                  * has bad/racey automagic that prevents synchronizing here.
1489                  * even kernel mode drivers often miss them.
1490                  */
1491                 if (value == 0) {
1492                         INFO (dev, "configuration #%d\n", dev->current_config);
1493                         if (dev->usermode_setup) {
1494                                 dev->setup_can_stall = 0;
1495                                 goto delegate;
1496                         }
1497                 }
1498                 break;
1499
1500 #ifndef CONFIG_USB_GADGET_PXA25X
1501         /* PXA automagically handles this request too */
1502         case USB_REQ_GET_CONFIGURATION:
1503                 if (ctrl->bRequestType != 0x80)
1504                         goto unrecognized;
1505                 *(u8 *)req->buf = dev->current_config;
1506                 value = min (w_length, (u16) 1);
1507                 break;
1508 #endif
1509
1510         default:
1511 unrecognized:
1512                 VDEBUG (dev, "%s req%02x.%02x v%04x i%04x l%d\n",
1513                         dev->usermode_setup ? "delegate" : "fail",
1514                         ctrl->bRequestType, ctrl->bRequest,
1515                         w_value, le16_to_cpu(ctrl->wIndex), w_length);
1516
1517                 /* if there's an ep0 reader, don't stall */
1518                 if (dev->usermode_setup) {
1519                         dev->setup_can_stall = 1;
1520 delegate:
1521                         dev->setup_in = (ctrl->bRequestType & USB_DIR_IN)
1522                                                 ? 1 : 0;
1523                         dev->setup_wLength = w_length;
1524                         dev->setup_out_ready = 0;
1525                         dev->setup_out_error = 0;
1526                         value = 0;
1527
1528                         /* read DATA stage for OUT right away */
1529                         if (unlikely (!dev->setup_in && w_length)) {
1530                                 value = setup_req (gadget->ep0, dev->req,
1531                                                         w_length);
1532                                 if (value < 0)
1533                                         break;
1534                                 value = usb_ep_queue (gadget->ep0, dev->req,
1535                                                         GFP_ATOMIC);
1536                                 if (value < 0) {
1537                                         clean_req (gadget->ep0, dev->req);
1538                                         break;
1539                                 }
1540
1541                                 /* we can't currently stall these */
1542                                 dev->setup_can_stall = 0;
1543                         }
1544
1545                         /* state changes when reader collects event */
1546                         event = next_event (dev, GADGETFS_SETUP);
1547                         event->u.setup = *ctrl;
1548                         ep0_readable (dev);
1549                         spin_unlock (&dev->lock);
1550                         return 0;
1551                 }
1552         }
1553
1554         /* proceed with data transfer and status phases? */
1555         if (value >= 0 && dev->state != STATE_DEV_SETUP) {
1556                 req->length = value;
1557                 req->zero = value < w_length;
1558                 value = usb_ep_queue (gadget->ep0, req, GFP_ATOMIC);
1559                 if (value < 0) {
1560                         DBG (dev, "ep_queue --> %d\n", value);
1561                         req->status = 0;
1562                 }
1563         }
1564
1565         /* device stalls when value < 0 */
1566         spin_unlock (&dev->lock);
1567         return value;
1568 }
1569
1570 static void destroy_ep_files (struct dev_data *dev)
1571 {
1572         struct list_head        *entry, *tmp;
1573
1574         DBG (dev, "%s %d\n", __func__, dev->state);
1575
1576         /* dev->state must prevent interference */
1577 restart:
1578         spin_lock_irq (&dev->lock);
1579         list_for_each_safe (entry, tmp, &dev->epfiles) {
1580                 struct ep_data  *ep;
1581                 struct inode    *parent;
1582                 struct dentry   *dentry;
1583
1584                 /* break link to FS */
1585                 ep = list_entry (entry, struct ep_data, epfiles);
1586                 list_del_init (&ep->epfiles);
1587                 dentry = ep->dentry;
1588                 ep->dentry = NULL;
1589                 parent = dentry->d_parent->d_inode;
1590
1591                 /* break link to controller */
1592                 if (ep->state == STATE_EP_ENABLED)
1593                         (void) usb_ep_disable (ep->ep);
1594                 ep->state = STATE_EP_UNBOUND;
1595                 usb_ep_free_request (ep->ep, ep->req);
1596                 ep->ep = NULL;
1597                 wake_up (&ep->wait);
1598                 put_ep (ep);
1599
1600                 spin_unlock_irq (&dev->lock);
1601
1602                 /* break link to dcache */
1603                 mutex_lock (&parent->i_mutex);
1604                 d_delete (dentry);
1605                 dput (dentry);
1606                 mutex_unlock (&parent->i_mutex);
1607
1608                 /* fds may still be open */
1609                 goto restart;
1610         }
1611         spin_unlock_irq (&dev->lock);
1612 }
1613
1614
1615 static struct inode *
1616 gadgetfs_create_file (struct super_block *sb, char const *name,
1617                 void *data, const struct file_operations *fops,
1618                 struct dentry **dentry_p);
1619
1620 static int activate_ep_files (struct dev_data *dev)
1621 {
1622         struct usb_ep   *ep;
1623         struct ep_data  *data;
1624
1625         gadget_for_each_ep (ep, dev->gadget) {
1626
1627                 data = kzalloc(sizeof(*data), GFP_KERNEL);
1628                 if (!data)
1629                         goto enomem0;
1630                 data->state = STATE_EP_DISABLED;
1631                 mutex_init(&data->lock);
1632                 init_waitqueue_head (&data->wait);
1633
1634                 strncpy (data->name, ep->name, sizeof (data->name) - 1);
1635                 atomic_set (&data->count, 1);
1636                 data->dev = dev;
1637                 get_dev (dev);
1638
1639                 data->ep = ep;
1640                 ep->driver_data = data;
1641
1642                 data->req = usb_ep_alloc_request (ep, GFP_KERNEL);
1643                 if (!data->req)
1644                         goto enomem1;
1645
1646                 data->inode = gadgetfs_create_file (dev->sb, data->name,
1647                                 data, &ep_config_operations,
1648                                 &data->dentry);
1649                 if (!data->inode)
1650                         goto enomem2;
1651                 list_add_tail (&data->epfiles, &dev->epfiles);
1652         }
1653         return 0;
1654
1655 enomem2:
1656         usb_ep_free_request (ep, data->req);
1657 enomem1:
1658         put_dev (dev);
1659         kfree (data);
1660 enomem0:
1661         DBG (dev, "%s enomem\n", __func__);
1662         destroy_ep_files (dev);
1663         return -ENOMEM;
1664 }
1665
1666 static void
1667 gadgetfs_unbind (struct usb_gadget *gadget)
1668 {
1669         struct dev_data         *dev = get_gadget_data (gadget);
1670
1671         DBG (dev, "%s\n", __func__);
1672
1673         spin_lock_irq (&dev->lock);
1674         dev->state = STATE_DEV_UNBOUND;
1675         spin_unlock_irq (&dev->lock);
1676
1677         destroy_ep_files (dev);
1678         gadget->ep0->driver_data = NULL;
1679         set_gadget_data (gadget, NULL);
1680
1681         /* we've already been disconnected ... no i/o is active */
1682         if (dev->req)
1683                 usb_ep_free_request (gadget->ep0, dev->req);
1684         DBG (dev, "%s done\n", __func__);
1685         put_dev (dev);
1686 }
1687
1688 static struct dev_data          *the_device;
1689
1690 static int
1691 gadgetfs_bind (struct usb_gadget *gadget)
1692 {
1693         struct dev_data         *dev = the_device;
1694
1695         if (!dev)
1696                 return -ESRCH;
1697         if (0 != strcmp (CHIP, gadget->name)) {
1698                 pr_err("%s expected %s controller not %s\n",
1699                         shortname, CHIP, gadget->name);
1700                 return -ENODEV;
1701         }
1702
1703         set_gadget_data (gadget, dev);
1704         dev->gadget = gadget;
1705         gadget->ep0->driver_data = dev;
1706
1707         /* preallocate control response and buffer */
1708         dev->req = usb_ep_alloc_request (gadget->ep0, GFP_KERNEL);
1709         if (!dev->req)
1710                 goto enomem;
1711         dev->req->context = NULL;
1712         dev->req->complete = epio_complete;
1713
1714         if (activate_ep_files (dev) < 0)
1715                 goto enomem;
1716
1717         INFO (dev, "bound to %s driver\n", gadget->name);
1718         spin_lock_irq(&dev->lock);
1719         dev->state = STATE_DEV_UNCONNECTED;
1720         spin_unlock_irq(&dev->lock);
1721         get_dev (dev);
1722         return 0;
1723
1724 enomem:
1725         gadgetfs_unbind (gadget);
1726         return -ENOMEM;
1727 }
1728
1729 static void
1730 gadgetfs_disconnect (struct usb_gadget *gadget)
1731 {
1732         struct dev_data         *dev = get_gadget_data (gadget);
1733         unsigned long           flags;
1734
1735         spin_lock_irqsave (&dev->lock, flags);
1736         if (dev->state == STATE_DEV_UNCONNECTED)
1737                 goto exit;
1738         dev->state = STATE_DEV_UNCONNECTED;
1739
1740         INFO (dev, "disconnected\n");
1741         next_event (dev, GADGETFS_DISCONNECT);
1742         ep0_readable (dev);
1743 exit:
1744         spin_unlock_irqrestore (&dev->lock, flags);
1745 }
1746
1747 static void
1748 gadgetfs_suspend (struct usb_gadget *gadget)
1749 {
1750         struct dev_data         *dev = get_gadget_data (gadget);
1751
1752         INFO (dev, "suspended from state %d\n", dev->state);
1753         spin_lock (&dev->lock);
1754         switch (dev->state) {
1755         case STATE_DEV_SETUP:           // VERY odd... host died??
1756         case STATE_DEV_CONNECTED:
1757         case STATE_DEV_UNCONNECTED:
1758                 next_event (dev, GADGETFS_SUSPEND);
1759                 ep0_readable (dev);
1760                 /* FALLTHROUGH */
1761         default:
1762                 break;
1763         }
1764         spin_unlock (&dev->lock);
1765 }
1766
1767 static struct usb_gadget_driver gadgetfs_driver = {
1768 #ifdef  CONFIG_USB_GADGET_DUALSPEED
1769         .max_speed      = USB_SPEED_HIGH,
1770 #else
1771         .max_speed      = USB_SPEED_FULL,
1772 #endif
1773         .function       = (char *) driver_desc,
1774         .unbind         = gadgetfs_unbind,
1775         .setup          = gadgetfs_setup,
1776         .disconnect     = gadgetfs_disconnect,
1777         .suspend        = gadgetfs_suspend,
1778
1779         .driver = {
1780                 .name           = (char *) shortname,
1781         },
1782 };
1783
1784 /*----------------------------------------------------------------------*/
1785
1786 static void gadgetfs_nop(struct usb_gadget *arg) { }
1787
1788 static int gadgetfs_probe (struct usb_gadget *gadget)
1789 {
1790         CHIP = gadget->name;
1791         return -EISNAM;
1792 }
1793
1794 static struct usb_gadget_driver probe_driver = {
1795         .max_speed      = USB_SPEED_HIGH,
1796         .unbind         = gadgetfs_nop,
1797         .setup          = (void *)gadgetfs_nop,
1798         .disconnect     = gadgetfs_nop,
1799         .driver = {
1800                 .name           = "nop",
1801         },
1802 };
1803
1804
1805 /* DEVICE INITIALIZATION
1806  *
1807  *     fd = open ("/dev/gadget/$CHIP", O_RDWR)
1808  *     status = write (fd, descriptors, sizeof descriptors)
1809  *
1810  * That write establishes the device configuration, so the kernel can
1811  * bind to the controller ... guaranteeing it can handle enumeration
1812  * at all necessary speeds.  Descriptor order is:
1813  *
1814  * . message tag (u32, host order) ... for now, must be zero; it
1815  *      would change to support features like multi-config devices
1816  * . full/low speed config ... all wTotalLength bytes (with interface,
1817  *      class, altsetting, endpoint, and other descriptors)
1818  * . high speed config ... all descriptors, for high speed operation;
1819  *      this one's optional except for high-speed hardware
1820  * . device descriptor
1821  *
1822  * Endpoints are not yet enabled. Drivers must wait until device
1823  * configuration and interface altsetting changes create
1824  * the need to configure (or unconfigure) them.
1825  *
1826  * After initialization, the device stays active for as long as that
1827  * $CHIP file is open.  Events must then be read from that descriptor,
1828  * such as configuration notifications.
1829  */
1830
1831 static int is_valid_config (struct usb_config_descriptor *config)
1832 {
1833         return config->bDescriptorType == USB_DT_CONFIG
1834                 && config->bLength == USB_DT_CONFIG_SIZE
1835                 && config->bConfigurationValue != 0
1836                 && (config->bmAttributes & USB_CONFIG_ATT_ONE) != 0
1837                 && (config->bmAttributes & USB_CONFIG_ATT_WAKEUP) == 0;
1838         /* FIXME if gadget->is_otg, _must_ include an otg descriptor */
1839         /* FIXME check lengths: walk to end */
1840 }
1841
1842 static ssize_t
1843 dev_config (struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
1844 {
1845         struct dev_data         *dev = fd->private_data;
1846         ssize_t                 value = len, length = len;
1847         unsigned                total;
1848         u32                     tag;
1849         char                    *kbuf;
1850
1851         if (len < (USB_DT_CONFIG_SIZE + USB_DT_DEVICE_SIZE + 4))
1852                 return -EINVAL;
1853
1854         /* we might need to change message format someday */
1855         if (copy_from_user (&tag, buf, 4))
1856                 return -EFAULT;
1857         if (tag != 0)
1858                 return -EINVAL;
1859         buf += 4;
1860         length -= 4;
1861
1862         kbuf = memdup_user(buf, length);
1863         if (IS_ERR(kbuf))
1864                 return PTR_ERR(kbuf);
1865
1866         spin_lock_irq (&dev->lock);
1867         value = -EINVAL;
1868         if (dev->buf)
1869                 goto fail;
1870         dev->buf = kbuf;
1871
1872         /* full or low speed config */
1873         dev->config = (void *) kbuf;
1874         total = le16_to_cpu(dev->config->wTotalLength);
1875         if (!is_valid_config (dev->config) || total >= length)
1876                 goto fail;
1877         kbuf += total;
1878         length -= total;
1879
1880         /* optional high speed config */
1881         if (kbuf [1] == USB_DT_CONFIG) {
1882                 dev->hs_config = (void *) kbuf;
1883                 total = le16_to_cpu(dev->hs_config->wTotalLength);
1884                 if (!is_valid_config (dev->hs_config) || total >= length)
1885                         goto fail;
1886                 kbuf += total;
1887                 length -= total;
1888         }
1889
1890         /* could support multiple configs, using another encoding! */
1891
1892         /* device descriptor (tweaked for paranoia) */
1893         if (length != USB_DT_DEVICE_SIZE)
1894                 goto fail;
1895         dev->dev = (void *)kbuf;
1896         if (dev->dev->bLength != USB_DT_DEVICE_SIZE
1897                         || dev->dev->bDescriptorType != USB_DT_DEVICE
1898                         || dev->dev->bNumConfigurations != 1)
1899                 goto fail;
1900         dev->dev->bNumConfigurations = 1;
1901         dev->dev->bcdUSB = cpu_to_le16 (0x0200);
1902
1903         /* triggers gadgetfs_bind(); then we can enumerate. */
1904         spin_unlock_irq (&dev->lock);
1905         value = usb_gadget_probe_driver(&gadgetfs_driver, gadgetfs_bind);
1906         if (value != 0) {
1907                 kfree (dev->buf);
1908                 dev->buf = NULL;
1909         } else {
1910                 /* at this point "good" hardware has for the first time
1911                  * let the USB the host see us.  alternatively, if users
1912                  * unplug/replug that will clear all the error state.
1913                  *
1914                  * note:  everything running before here was guaranteed
1915                  * to choke driver model style diagnostics.  from here
1916                  * on, they can work ... except in cleanup paths that
1917                  * kick in after the ep0 descriptor is closed.
1918                  */
1919                 fd->f_op = &ep0_io_operations;
1920                 value = len;
1921         }
1922         return value;
1923
1924 fail:
1925         spin_unlock_irq (&dev->lock);
1926         pr_debug ("%s: %s fail %Zd, %p\n", shortname, __func__, value, dev);
1927         kfree (dev->buf);
1928         dev->buf = NULL;
1929         return value;
1930 }
1931
1932 static int
1933 dev_open (struct inode *inode, struct file *fd)
1934 {
1935         struct dev_data         *dev = inode->i_private;
1936         int                     value = -EBUSY;
1937
1938         spin_lock_irq(&dev->lock);
1939         if (dev->state == STATE_DEV_DISABLED) {
1940                 dev->ev_next = 0;
1941                 dev->state = STATE_DEV_OPENED;
1942                 fd->private_data = dev;
1943                 get_dev (dev);
1944                 value = 0;
1945         }
1946         spin_unlock_irq(&dev->lock);
1947         return value;
1948 }
1949
1950 static const struct file_operations dev_init_operations = {
1951         .owner =        THIS_MODULE,
1952         .llseek =       no_llseek,
1953
1954         .open =         dev_open,
1955         .write =        dev_config,
1956         .fasync =       ep0_fasync,
1957         .unlocked_ioctl = dev_ioctl,
1958         .release =      dev_release,
1959 };
1960
1961 /*----------------------------------------------------------------------*/
1962
1963 /* FILESYSTEM AND SUPERBLOCK OPERATIONS
1964  *
1965  * Mounting the filesystem creates a controller file, used first for
1966  * device configuration then later for event monitoring.
1967  */
1968
1969
1970 /* FIXME PAM etc could set this security policy without mount options
1971  * if epfiles inherited ownership and permissons from ep0 ...
1972  */
1973
1974 static unsigned default_uid;
1975 static unsigned default_gid;
1976 static unsigned default_perm = S_IRUSR | S_IWUSR;
1977
1978 module_param (default_uid, uint, 0644);
1979 module_param (default_gid, uint, 0644);
1980 module_param (default_perm, uint, 0644);
1981
1982
1983 static struct inode *
1984 gadgetfs_make_inode (struct super_block *sb,
1985                 void *data, const struct file_operations *fops,
1986                 int mode)
1987 {
1988         struct inode *inode = new_inode (sb);
1989
1990         if (inode) {
1991                 inode->i_ino = get_next_ino();
1992                 inode->i_mode = mode;
1993                 inode->i_uid = default_uid;
1994                 inode->i_gid = default_gid;
1995                 inode->i_atime = inode->i_mtime = inode->i_ctime
1996                                 = CURRENT_TIME;
1997                 inode->i_private = data;
1998                 inode->i_fop = fops;
1999         }
2000         return inode;
2001 }
2002
2003 /* creates in fs root directory, so non-renamable and non-linkable.
2004  * so inode and dentry are paired, until device reconfig.
2005  */
2006 static struct inode *
2007 gadgetfs_create_file (struct super_block *sb, char const *name,
2008                 void *data, const struct file_operations *fops,
2009                 struct dentry **dentry_p)
2010 {
2011         struct dentry   *dentry;
2012         struct inode    *inode;
2013
2014         dentry = d_alloc_name(sb->s_root, name);
2015         if (!dentry)
2016                 return NULL;
2017
2018         inode = gadgetfs_make_inode (sb, data, fops,
2019                         S_IFREG | (default_perm & S_IRWXUGO));
2020         if (!inode) {
2021                 dput(dentry);
2022                 return NULL;
2023         }
2024         d_add (dentry, inode);
2025         *dentry_p = dentry;
2026         return inode;
2027 }
2028
2029 static const struct super_operations gadget_fs_operations = {
2030         .statfs =       simple_statfs,
2031         .drop_inode =   generic_delete_inode,
2032 };
2033
2034 static int
2035 gadgetfs_fill_super (struct super_block *sb, void *opts, int silent)
2036 {
2037         struct inode    *inode;
2038         struct dev_data *dev;
2039
2040         if (the_device)
2041                 return -ESRCH;
2042
2043         /* fake probe to determine $CHIP */
2044         (void) usb_gadget_probe_driver(&probe_driver, gadgetfs_probe);
2045         if (!CHIP)
2046                 return -ENODEV;
2047
2048         /* superblock */
2049         sb->s_blocksize = PAGE_CACHE_SIZE;
2050         sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
2051         sb->s_magic = GADGETFS_MAGIC;
2052         sb->s_op = &gadget_fs_operations;
2053         sb->s_time_gran = 1;
2054
2055         /* root inode */
2056         inode = gadgetfs_make_inode (sb,
2057                         NULL, &simple_dir_operations,
2058                         S_IFDIR | S_IRUGO | S_IXUGO);
2059         if (!inode)
2060                 goto Enomem;
2061         inode->i_op = &simple_dir_inode_operations;
2062         if (!(sb->s_root = d_make_root (inode)))
2063                 goto Enomem;
2064
2065         /* the ep0 file is named after the controller we expect;
2066          * user mode code can use it for sanity checks, like we do.
2067          */
2068         dev = dev_new ();
2069         if (!dev)
2070                 goto Enomem;
2071
2072         dev->sb = sb;
2073         if (!gadgetfs_create_file (sb, CHIP,
2074                                 dev, &dev_init_operations,
2075                                 &dev->dentry)) {
2076                 put_dev(dev);
2077                 goto Enomem;
2078         }
2079
2080         /* other endpoint files are available after hardware setup,
2081          * from binding to a controller.
2082          */
2083         the_device = dev;
2084         return 0;
2085
2086 Enomem:
2087         return -ENOMEM;
2088 }
2089
2090 /* "mount -t gadgetfs path /dev/gadget" ends up here */
2091 static struct dentry *
2092 gadgetfs_mount (struct file_system_type *t, int flags,
2093                 const char *path, void *opts)
2094 {
2095         return mount_single (t, flags, opts, gadgetfs_fill_super);
2096 }
2097
2098 static void
2099 gadgetfs_kill_sb (struct super_block *sb)
2100 {
2101         kill_litter_super (sb);
2102         if (the_device) {
2103                 put_dev (the_device);
2104                 the_device = NULL;
2105         }
2106 }
2107
2108 /*----------------------------------------------------------------------*/
2109
2110 static struct file_system_type gadgetfs_type = {
2111         .owner          = THIS_MODULE,
2112         .name           = shortname,
2113         .mount          = gadgetfs_mount,
2114         .kill_sb        = gadgetfs_kill_sb,
2115 };
2116
2117 /*----------------------------------------------------------------------*/
2118
2119 static int __init init (void)
2120 {
2121         int status;
2122
2123         status = register_filesystem (&gadgetfs_type);
2124         if (status == 0)
2125                 pr_info ("%s: %s, version " DRIVER_VERSION "\n",
2126                         shortname, driver_desc);
2127         return status;
2128 }
2129 module_init (init);
2130
2131 static void __exit cleanup (void)
2132 {
2133         pr_debug ("unregister %s\n", shortname);
2134         unregister_filesystem (&gadgetfs_type);
2135 }
2136 module_exit (cleanup);
2137