Merge branch 'upstream-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/linvil...
[linux-2.6] / 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      DEBUG                   /* data to help fault diagnosis */
24 // #define      VERBOSE         /* extra debug messages (success too) */
25
26 #include <linux/init.h>
27 #include <linux/module.h>
28 #include <linux/fs.h>
29 #include <linux/pagemap.h>
30 #include <linux/uts.h>
31 #include <linux/wait.h>
32 #include <linux/compiler.h>
33 #include <asm/uaccess.h>
34 #include <linux/slab.h>
35
36 #include <linux/device.h>
37 #include <linux/moduleparam.h>
38
39 #include <linux/usb_gadgetfs.h>
40 #include <linux/usb_gadget.h>
41
42
43 /*
44  * The gadgetfs API maps each endpoint to a file descriptor so that you
45  * can use standard synchronous read/write calls for I/O.  There's some
46  * O_NONBLOCK and O_ASYNC/FASYNC style i/o support.  Example usermode
47  * drivers show how this works in practice.  You can also use AIO to
48  * eliminate I/O gaps between requests, to help when streaming data.
49  *
50  * Key parts that must be USB-specific are protocols defining how the
51  * read/write operations relate to the hardware state machines.  There
52  * are two types of files.  One type is for the device, implementing ep0.
53  * The other type is for each IN or OUT endpoint.  In both cases, the
54  * user mode driver must configure the hardware before using it.
55  *
56  * - First, dev_config() is called when /dev/gadget/$CHIP is configured
57  *   (by writing configuration and device descriptors).  Afterwards it
58  *   may serve as a source of device events, used to handle all control
59  *   requests other than basic enumeration.
60  *
61  * - Then either immediately, or after a SET_CONFIGURATION control request,
62  *   ep_config() is called when each /dev/gadget/ep* file is configured
63  *   (by writing endpoint descriptors).  Afterwards these files are used
64  *   to write() IN data or to read() OUT data.  To halt the endpoint, a
65  *   "wrong direction" request is issued (like reading an IN endpoint).
66  *
67  * Unlike "usbfs" the only ioctl()s are for things that are rare, and maybe
68  * not possible on all hardware.  For example, precise fault handling with
69  * respect to data left in endpoint fifos after aborted operations; or
70  * selective clearing of endpoint halts, to implement SET_INTERFACE.
71  */
72
73 #define DRIVER_DESC     "USB Gadget filesystem"
74 #define DRIVER_VERSION  "24 Aug 2004"
75
76 static const char driver_desc [] = DRIVER_DESC;
77 static const char shortname [] = "gadgetfs";
78
79 MODULE_DESCRIPTION (DRIVER_DESC);
80 MODULE_AUTHOR ("David Brownell");
81 MODULE_LICENSE ("GPL");
82
83
84 /*----------------------------------------------------------------------*/
85
86 #define GADGETFS_MAGIC          0xaee71ee7
87 #define DMA_ADDR_INVALID        (~(dma_addr_t)0)
88
89 /* /dev/gadget/$CHIP represents ep0 and the whole device */
90 enum ep0_state {
91         /* DISBLED is the initial state.
92          */
93         STATE_DEV_DISABLED = 0,
94
95         /* Only one open() of /dev/gadget/$CHIP; only one file tracks
96          * ep0/device i/o modes and binding to the controller.  Driver
97          * must always write descriptors to initialize the device, then
98          * the device becomes UNCONNECTED until enumeration.
99          */
100         STATE_OPENED,
101
102         /* From then on, ep0 fd is in either of two basic modes:
103          * - (UN)CONNECTED: read usb_gadgetfs_event(s) from it
104          * - SETUP: read/write will transfer control data and succeed;
105          *   or if "wrong direction", performs protocol stall
106          */
107         STATE_UNCONNECTED,
108         STATE_CONNECTED,
109         STATE_SETUP,
110
111         /* UNBOUND means the driver closed ep0, so the device won't be
112          * accessible again (DEV_DISABLED) until all fds are closed.
113          */
114         STATE_DEV_UNBOUND,
115 };
116
117 /* enough for the whole queue: most events invalidate others */
118 #define N_EVENT                 5
119
120 struct dev_data {
121         spinlock_t                      lock;
122         atomic_t                        count;
123         enum ep0_state                  state;
124         struct usb_gadgetfs_event       event [N_EVENT];
125         unsigned                        ev_next;
126         struct fasync_struct            *fasync;
127         u8                              current_config;
128
129         /* drivers reading ep0 MUST handle control requests (SETUP)
130          * reported that way; else the host will time out.
131          */
132         unsigned                        usermode_setup : 1,
133                                         setup_in : 1,
134                                         setup_can_stall : 1,
135                                         setup_out_ready : 1,
136                                         setup_out_error : 1,
137                                         setup_abort : 1;
138         unsigned                        setup_wLength;
139
140         /* the rest is basically write-once */
141         struct usb_config_descriptor    *config, *hs_config;
142         struct usb_device_descriptor    *dev;
143         struct usb_request              *req;
144         struct usb_gadget               *gadget;
145         struct list_head                epfiles;
146         void                            *buf;
147         wait_queue_head_t               wait;
148         struct super_block              *sb;
149         struct dentry                   *dentry;
150
151         /* except this scratch i/o buffer for ep0 */
152         u8                              rbuf [256];
153 };
154
155 static inline void get_dev (struct dev_data *data)
156 {
157         atomic_inc (&data->count);
158 }
159
160 static void put_dev (struct dev_data *data)
161 {
162         if (likely (!atomic_dec_and_test (&data->count)))
163                 return;
164         /* needs no more cleanup */
165         BUG_ON (waitqueue_active (&data->wait));
166         kfree (data);
167 }
168
169 static struct dev_data *dev_new (void)
170 {
171         struct dev_data         *dev;
172
173         dev = kmalloc (sizeof *dev, GFP_KERNEL);
174         if (!dev)
175                 return NULL;
176         memset (dev, 0, sizeof *dev);
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_DEFER_ENABLE,
192         STATE_EP_ENABLED,
193         STATE_EP_UNBOUND,
194 };
195
196 struct ep_data {
197         struct semaphore                lock;
198         enum ep_state                   state;
199         atomic_t                        count;
200         struct dev_data                 *dev;
201         /* must hold dev->lock before accessing ep or req */
202         struct usb_ep                   *ep;
203         struct usb_request              *req;
204         ssize_t                         status;
205         char                            name [16];
206         struct usb_endpoint_descriptor  desc, hs_desc;
207         struct list_head                epfiles;
208         wait_queue_head_t               wait;
209         struct dentry                   *dentry;
210         struct inode                    *inode;
211 };
212
213 static inline void get_ep (struct ep_data *data)
214 {
215         atomic_inc (&data->count);
216 }
217
218 static void put_ep (struct ep_data *data)
219 {
220         if (likely (!atomic_dec_and_test (&data->count)))
221                 return;
222         put_dev (data->dev);
223         /* needs no more cleanup */
224         BUG_ON (!list_empty (&data->epfiles));
225         BUG_ON (waitqueue_active (&data->wait));
226         BUG_ON (down_trylock (&data->lock) != 0);
227         kfree (data);
228 }
229
230 /*----------------------------------------------------------------------*/
231
232 /* most "how to use the hardware" policy choices are in userspace:
233  * mapping endpoint roles (which the driver needs) to the capabilities
234  * which the usb controller has.  most of those capabilities are exposed
235  * implicitly, starting with the driver name and then endpoint names.
236  */
237
238 static const char *CHIP;
239
240 /*----------------------------------------------------------------------*/
241
242 /* NOTE:  don't use dev_printk calls before binding to the gadget
243  * at the end of ep0 configuration, or after unbind.
244  */
245
246 /* too wordy: dev_printk(level , &(d)->gadget->dev , fmt , ## args) */
247 #define xprintk(d,level,fmt,args...) \
248         printk(level "%s: " fmt , shortname , ## args)
249
250 #ifdef DEBUG
251 #define DBG(dev,fmt,args...) \
252         xprintk(dev , KERN_DEBUG , fmt , ## args)
253 #else
254 #define DBG(dev,fmt,args...) \
255         do { } while (0)
256 #endif /* DEBUG */
257
258 #ifdef VERBOSE
259 #define VDEBUG  DBG
260 #else
261 #define VDEBUG(dev,fmt,args...) \
262         do { } while (0)
263 #endif /* DEBUG */
264
265 #define ERROR(dev,fmt,args...) \
266         xprintk(dev , KERN_ERR , fmt , ## args)
267 #define WARN(dev,fmt,args...) \
268         xprintk(dev , KERN_WARNING , fmt , ## args)
269 #define INFO(dev,fmt,args...) \
270         xprintk(dev , KERN_INFO , fmt , ## args)
271
272
273 /*----------------------------------------------------------------------*/
274
275 /* SYNCHRONOUS ENDPOINT OPERATIONS (bulk/intr/iso)
276  *
277  * After opening, configure non-control endpoints.  Then use normal
278  * stream read() and write() requests; and maybe ioctl() to get more
279  * precise FIFO status when recovering from cancellation.
280  */
281
282 static void epio_complete (struct usb_ep *ep, struct usb_request *req)
283 {
284         struct ep_data  *epdata = ep->driver_data;
285
286         if (!req->context)
287                 return;
288         if (req->status)
289                 epdata->status = req->status;
290         else
291                 epdata->status = req->actual;
292         complete ((struct completion *)req->context);
293 }
294
295 /* tasklock endpoint, returning when it's connected.
296  * still need dev->lock to use epdata->ep.
297  */
298 static int
299 get_ready_ep (unsigned f_flags, struct ep_data *epdata)
300 {
301         int     val;
302
303         if (f_flags & O_NONBLOCK) {
304                 if (down_trylock (&epdata->lock) != 0)
305                         goto nonblock;
306                 if (epdata->state != STATE_EP_ENABLED) {
307                         up (&epdata->lock);
308 nonblock:
309                         val = -EAGAIN;
310                 } else
311                         val = 0;
312                 return val;
313         }
314
315         if ((val = down_interruptible (&epdata->lock)) < 0)
316                 return val;
317 newstate:
318         switch (epdata->state) {
319         case STATE_EP_ENABLED:
320                 break;
321         case STATE_EP_DEFER_ENABLE:
322                 DBG (epdata->dev, "%s wait for host\n", epdata->name);
323                 if ((val = wait_event_interruptible (epdata->wait, 
324                                 epdata->state != STATE_EP_DEFER_ENABLE
325                                 || epdata->dev->state == STATE_DEV_UNBOUND
326                                 )) < 0)
327                         goto fail;
328                 goto newstate;
329         // case STATE_EP_DISABLED:              /* "can't happen" */
330         // case STATE_EP_READY:                 /* "can't happen" */
331         default:                                /* error! */
332                 pr_debug ("%s: ep %p not available, state %d\n",
333                                 shortname, epdata, epdata->state);
334                 // FALLTHROUGH
335         case STATE_EP_UNBOUND:                  /* clean disconnect */
336                 val = -ENODEV;
337 fail:
338                 up (&epdata->lock);
339         }
340         return val;
341 }
342
343 static ssize_t
344 ep_io (struct ep_data *epdata, void *buf, unsigned len)
345 {
346         DECLARE_COMPLETION (done);
347         int value;
348
349         spin_lock_irq (&epdata->dev->lock);
350         if (likely (epdata->ep != NULL)) {
351                 struct usb_request      *req = epdata->req;
352
353                 req->context = &done;
354                 req->complete = epio_complete;
355                 req->buf = buf;
356                 req->length = len;
357                 value = usb_ep_queue (epdata->ep, req, GFP_ATOMIC);
358         } else
359                 value = -ENODEV;
360         spin_unlock_irq (&epdata->dev->lock);
361
362         if (likely (value == 0)) {
363                 value = wait_event_interruptible (done.wait, done.done);
364                 if (value != 0) {
365                         spin_lock_irq (&epdata->dev->lock);
366                         if (likely (epdata->ep != NULL)) {
367                                 DBG (epdata->dev, "%s i/o interrupted\n",
368                                                 epdata->name);
369                                 usb_ep_dequeue (epdata->ep, epdata->req);
370                                 spin_unlock_irq (&epdata->dev->lock);
371
372                                 wait_event (done.wait, done.done);
373                                 if (epdata->status == -ECONNRESET)
374                                         epdata->status = -EINTR;
375                         } else {
376                                 spin_unlock_irq (&epdata->dev->lock);
377
378                                 DBG (epdata->dev, "endpoint gone\n");
379                                 epdata->status = -ENODEV;
380                         }
381                 }
382                 return epdata->status;
383         }
384         return value;
385 }
386
387
388 /* handle a synchronous OUT bulk/intr/iso transfer */
389 static ssize_t
390 ep_read (struct file *fd, char __user *buf, size_t len, loff_t *ptr)
391 {
392         struct ep_data          *data = fd->private_data;
393         void                    *kbuf;
394         ssize_t                 value;
395
396         if ((value = get_ready_ep (fd->f_flags, data)) < 0)
397                 return value;
398
399         /* halt any endpoint by doing a "wrong direction" i/o call */
400         if (data->desc.bEndpointAddress & USB_DIR_IN) {
401                 if ((data->desc.bmAttributes & USB_ENDPOINT_XFERTYPE_MASK)
402                                 == USB_ENDPOINT_XFER_ISOC)
403                         return -EINVAL;
404                 DBG (data->dev, "%s halt\n", data->name);
405                 spin_lock_irq (&data->dev->lock);
406                 if (likely (data->ep != NULL))
407                         usb_ep_set_halt (data->ep);
408                 spin_unlock_irq (&data->dev->lock);
409                 up (&data->lock);
410                 return -EBADMSG;
411         }
412
413         /* FIXME readahead for O_NONBLOCK and poll(); careful with ZLPs */
414
415         value = -ENOMEM;
416         kbuf = kmalloc (len, SLAB_KERNEL);
417         if (unlikely (!kbuf))
418                 goto free1;
419
420         value = ep_io (data, kbuf, len);
421         VDEBUG (data->dev, "%s read %zu OUT, status %d\n",
422                 data->name, len, (int) value);
423         if (value >= 0 && copy_to_user (buf, kbuf, value))
424                 value = -EFAULT;
425
426 free1:
427         up (&data->lock);
428         kfree (kbuf);
429         return value;
430 }
431
432 /* handle a synchronous IN bulk/intr/iso transfer */
433 static ssize_t
434 ep_write (struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
435 {
436         struct ep_data          *data = fd->private_data;
437         void                    *kbuf;
438         ssize_t                 value;
439
440         if ((value = get_ready_ep (fd->f_flags, data)) < 0)
441                 return value;
442
443         /* halt any endpoint by doing a "wrong direction" i/o call */
444         if (!(data->desc.bEndpointAddress & USB_DIR_IN)) {
445                 if ((data->desc.bmAttributes & USB_ENDPOINT_XFERTYPE_MASK)
446                                 == USB_ENDPOINT_XFER_ISOC)
447                         return -EINVAL;
448                 DBG (data->dev, "%s halt\n", data->name);
449                 spin_lock_irq (&data->dev->lock);
450                 if (likely (data->ep != NULL))
451                         usb_ep_set_halt (data->ep);
452                 spin_unlock_irq (&data->dev->lock);
453                 up (&data->lock);
454                 return -EBADMSG;
455         }
456
457         /* FIXME writebehind for O_NONBLOCK and poll(), qlen = 1 */
458
459         value = -ENOMEM;
460         kbuf = kmalloc (len, SLAB_KERNEL);
461         if (!kbuf)
462                 goto free1;
463         if (copy_from_user (kbuf, buf, len)) {
464                 value = -EFAULT;
465                 goto free1;
466         }
467
468         value = ep_io (data, kbuf, len);
469         VDEBUG (data->dev, "%s write %zu IN, status %d\n",
470                 data->name, len, (int) value);
471 free1:
472         up (&data->lock);
473         kfree (kbuf);
474         return value;
475 }
476
477 static int
478 ep_release (struct inode *inode, struct file *fd)
479 {
480         struct ep_data          *data = fd->private_data;
481
482         /* clean up if this can be reopened */
483         if (data->state != STATE_EP_UNBOUND) {
484                 data->state = STATE_EP_DISABLED;
485                 data->desc.bDescriptorType = 0;
486                 data->hs_desc.bDescriptorType = 0;
487                 usb_ep_disable(data->ep);
488         }
489         put_ep (data);
490         return 0;
491 }
492
493 static int ep_ioctl (struct inode *inode, struct file *fd,
494                 unsigned code, unsigned long value)
495 {
496         struct ep_data          *data = fd->private_data;
497         int                     status;
498
499         if ((status = get_ready_ep (fd->f_flags, data)) < 0)
500                 return status;
501
502         spin_lock_irq (&data->dev->lock);
503         if (likely (data->ep != NULL)) {
504                 switch (code) {
505                 case GADGETFS_FIFO_STATUS:
506                         status = usb_ep_fifo_status (data->ep);
507                         break;
508                 case GADGETFS_FIFO_FLUSH:
509                         usb_ep_fifo_flush (data->ep);
510                         break;
511                 case GADGETFS_CLEAR_HALT:
512                         status = usb_ep_clear_halt (data->ep);
513                         break;
514                 default:
515                         status = -ENOTTY;
516                 }
517         } else
518                 status = -ENODEV;
519         spin_unlock_irq (&data->dev->lock);
520         up (&data->lock);
521         return status;
522 }
523
524 /*----------------------------------------------------------------------*/
525
526 /* ASYNCHRONOUS ENDPOINT I/O OPERATIONS (bulk/intr/iso) */
527
528 struct kiocb_priv {
529         struct usb_request      *req;
530         struct ep_data          *epdata;
531         void                    *buf;
532         char __user             *ubuf;
533         unsigned                actual;
534 };
535
536 static int ep_aio_cancel(struct kiocb *iocb, struct io_event *e)
537 {
538         struct kiocb_priv       *priv = iocb->private;
539         struct ep_data          *epdata;
540         int                     value;
541
542         local_irq_disable();
543         epdata = priv->epdata;
544         // spin_lock(&epdata->dev->lock);
545         kiocbSetCancelled(iocb);
546         if (likely(epdata && epdata->ep && priv->req))
547                 value = usb_ep_dequeue (epdata->ep, priv->req);
548         else
549                 value = -EINVAL;
550         // spin_unlock(&epdata->dev->lock);
551         local_irq_enable();
552
553         aio_put_req(iocb);
554         return value;
555 }
556
557 static ssize_t ep_aio_read_retry(struct kiocb *iocb)
558 {
559         struct kiocb_priv       *priv = iocb->private;
560         ssize_t                 status = priv->actual;
561
562         /* we "retry" to get the right mm context for this: */
563         status = copy_to_user(priv->ubuf, priv->buf, priv->actual);
564         if (unlikely(0 != status))
565                 status = -EFAULT;
566         else
567                 status = priv->actual;
568         kfree(priv->buf);
569         kfree(priv);
570         aio_put_req(iocb);
571         return status;
572 }
573
574 static void ep_aio_complete(struct usb_ep *ep, struct usb_request *req)
575 {
576         struct kiocb            *iocb = req->context;
577         struct kiocb_priv       *priv = iocb->private;
578         struct ep_data          *epdata = priv->epdata;
579
580         /* lock against disconnect (and ideally, cancel) */
581         spin_lock(&epdata->dev->lock);
582         priv->req = NULL;
583         priv->epdata = NULL;
584         if (NULL == iocb->ki_retry
585                         || unlikely(0 == req->actual)
586                         || unlikely(kiocbIsCancelled(iocb))) {
587                 kfree(req->buf);
588                 kfree(priv);
589                 iocb->private = NULL;
590                 /* aio_complete() reports bytes-transferred _and_ faults */
591                 if (unlikely(kiocbIsCancelled(iocb)))
592                         aio_put_req(iocb);
593                 else
594                         aio_complete(iocb,
595                                 req->actual ? req->actual : req->status,
596                                 req->status);
597         } else {
598                 /* retry() won't report both; so we hide some faults */
599                 if (unlikely(0 != req->status))
600                         DBG(epdata->dev, "%s fault %d len %d\n",
601                                 ep->name, req->status, req->actual);
602
603                 priv->buf = req->buf;
604                 priv->actual = req->actual;
605                 kick_iocb(iocb);
606         }
607         spin_unlock(&epdata->dev->lock);
608
609         usb_ep_free_request(ep, req);
610         put_ep(epdata);
611 }
612
613 static ssize_t
614 ep_aio_rwtail(
615         struct kiocb    *iocb,
616         char            *buf,
617         size_t          len,
618         struct ep_data  *epdata,
619         char __user     *ubuf
620 )
621 {
622         struct kiocb_priv       *priv = (void *) &iocb->private;
623         struct usb_request      *req;
624         ssize_t                 value;
625
626         priv = kmalloc(sizeof *priv, GFP_KERNEL);
627         if (!priv) {
628                 value = -ENOMEM;
629 fail:
630                 kfree(buf);
631                 return value;
632         }
633         iocb->private = priv;
634         priv->ubuf = ubuf;
635
636         value = get_ready_ep(iocb->ki_filp->f_flags, epdata);
637         if (unlikely(value < 0)) {
638                 kfree(priv);
639                 goto fail;
640         }
641
642         iocb->ki_cancel = ep_aio_cancel;
643         get_ep(epdata);
644         priv->epdata = epdata;
645         priv->actual = 0;
646
647         /* each kiocb is coupled to one usb_request, but we can't
648          * allocate or submit those if the host disconnected.
649          */
650         spin_lock_irq(&epdata->dev->lock);
651         if (likely(epdata->ep)) {
652                 req = usb_ep_alloc_request(epdata->ep, GFP_ATOMIC);
653                 if (likely(req)) {
654                         priv->req = req;
655                         req->buf = buf;
656                         req->length = len;
657                         req->complete = ep_aio_complete;
658                         req->context = iocb;
659                         value = usb_ep_queue(epdata->ep, req, GFP_ATOMIC);
660                         if (unlikely(0 != value))
661                                 usb_ep_free_request(epdata->ep, req);
662                 } else
663                         value = -EAGAIN;
664         } else
665                 value = -ENODEV;
666         spin_unlock_irq(&epdata->dev->lock);
667
668         up(&epdata->lock);
669
670         if (unlikely(value)) {
671                 kfree(priv);
672                 put_ep(epdata);
673         } else
674                 value = -EIOCBQUEUED;
675         return value;
676 }
677
678 static ssize_t
679 ep_aio_read(struct kiocb *iocb, char __user *ubuf, size_t len, loff_t o)
680 {
681         struct ep_data          *epdata = iocb->ki_filp->private_data;
682         char                    *buf;
683
684         if (unlikely(epdata->desc.bEndpointAddress & USB_DIR_IN))
685                 return -EINVAL;
686         buf = kmalloc(len, GFP_KERNEL);
687         if (unlikely(!buf))
688                 return -ENOMEM;
689         iocb->ki_retry = ep_aio_read_retry;
690         return ep_aio_rwtail(iocb, buf, len, epdata, ubuf);
691 }
692
693 static ssize_t
694 ep_aio_write(struct kiocb *iocb, const char __user *ubuf, size_t len, loff_t o)
695 {
696         struct ep_data          *epdata = iocb->ki_filp->private_data;
697         char                    *buf;
698
699         if (unlikely(!(epdata->desc.bEndpointAddress & USB_DIR_IN)))
700                 return -EINVAL;
701         buf = kmalloc(len, GFP_KERNEL);
702         if (unlikely(!buf))
703                 return -ENOMEM;
704         if (unlikely(copy_from_user(buf, ubuf, len) != 0)) {
705                 kfree(buf);
706                 return -EFAULT;
707         }
708         return ep_aio_rwtail(iocb, buf, len, epdata, NULL);
709 }
710
711 /*----------------------------------------------------------------------*/
712
713 /* used after endpoint configuration */
714 static struct file_operations ep_io_operations = {
715         .owner =        THIS_MODULE,
716         .llseek =       no_llseek,
717
718         .read =         ep_read,
719         .write =        ep_write,
720         .ioctl =        ep_ioctl,
721         .release =      ep_release,
722
723         .aio_read =     ep_aio_read,
724         .aio_write =    ep_aio_write,
725 };
726
727 /* ENDPOINT INITIALIZATION
728  *
729  *     fd = open ("/dev/gadget/$ENDPOINT", O_RDWR)
730  *     status = write (fd, descriptors, sizeof descriptors)
731  *
732  * That write establishes the endpoint configuration, configuring
733  * the controller to process bulk, interrupt, or isochronous transfers
734  * at the right maxpacket size, and so on.
735  *
736  * The descriptors are message type 1, identified by a host order u32
737  * at the beginning of what's written.  Descriptor order is: full/low
738  * speed descriptor, then optional high speed descriptor.
739  */
740 static ssize_t
741 ep_config (struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
742 {
743         struct ep_data          *data = fd->private_data;
744         struct usb_ep           *ep;
745         u32                     tag;
746         int                     value;
747
748         if ((value = down_interruptible (&data->lock)) < 0)
749                 return value;
750
751         if (data->state != STATE_EP_READY) {
752                 value = -EL2HLT;
753                 goto fail;
754         }
755
756         value = len;
757         if (len < USB_DT_ENDPOINT_SIZE + 4)
758                 goto fail0;
759
760         /* we might need to change message format someday */
761         if (copy_from_user (&tag, buf, 4)) {
762                 goto fail1;
763         }
764         if (tag != 1) {
765                 DBG(data->dev, "config %s, bad tag %d\n", data->name, tag);
766                 goto fail0;
767         }
768         buf += 4;
769         len -= 4;
770
771         /* NOTE:  audio endpoint extensions not accepted here;
772          * just don't include the extra bytes.
773          */
774
775         /* full/low speed descriptor, then high speed */
776         if (copy_from_user (&data->desc, buf, USB_DT_ENDPOINT_SIZE)) {
777                 goto fail1;
778         }
779         if (data->desc.bLength != USB_DT_ENDPOINT_SIZE
780                         || data->desc.bDescriptorType != USB_DT_ENDPOINT)
781                 goto fail0;
782         if (len != USB_DT_ENDPOINT_SIZE) {
783                 if (len != 2 * USB_DT_ENDPOINT_SIZE)
784                         goto fail0;
785                 if (copy_from_user (&data->hs_desc, buf + USB_DT_ENDPOINT_SIZE,
786                                         USB_DT_ENDPOINT_SIZE)) {
787                         goto fail1;
788                 }
789                 if (data->hs_desc.bLength != USB_DT_ENDPOINT_SIZE
790                                 || data->hs_desc.bDescriptorType
791                                         != USB_DT_ENDPOINT) {
792                         DBG(data->dev, "config %s, bad hs length or type\n",
793                                         data->name);
794                         goto fail0;
795                 }
796         }
797         value = len;
798
799         spin_lock_irq (&data->dev->lock);
800         if (data->dev->state == STATE_DEV_UNBOUND) {
801                 value = -ENOENT;
802                 goto gone;
803         } else if ((ep = data->ep) == NULL) {
804                 value = -ENODEV;
805                 goto gone;
806         }
807         switch (data->dev->gadget->speed) {
808         case USB_SPEED_LOW:
809         case USB_SPEED_FULL:
810                 value = usb_ep_enable (ep, &data->desc);
811                 if (value == 0)
812                         data->state = STATE_EP_ENABLED;
813                 break;
814 #ifdef  HIGHSPEED
815         case USB_SPEED_HIGH:
816                 /* fails if caller didn't provide that descriptor... */
817                 value = usb_ep_enable (ep, &data->hs_desc);
818                 if (value == 0)
819                         data->state = STATE_EP_ENABLED;
820                 break;
821 #endif
822         default:
823                 DBG (data->dev, "unconnected, %s init deferred\n",
824                                 data->name);
825                 data->state = STATE_EP_DEFER_ENABLE;
826         }
827         if (value == 0)
828                 fd->f_op = &ep_io_operations;
829 gone:
830         spin_unlock_irq (&data->dev->lock);
831         if (value < 0) {
832 fail:
833                 data->desc.bDescriptorType = 0;
834                 data->hs_desc.bDescriptorType = 0;
835         }
836         up (&data->lock);
837         return value;
838 fail0:
839         value = -EINVAL;
840         goto fail;
841 fail1:
842         value = -EFAULT;
843         goto fail;
844 }
845
846 static int
847 ep_open (struct inode *inode, struct file *fd)
848 {
849         struct ep_data          *data = inode->u.generic_ip;
850         int                     value = -EBUSY;
851
852         if (down_interruptible (&data->lock) != 0)
853                 return -EINTR;
854         spin_lock_irq (&data->dev->lock);
855         if (data->dev->state == STATE_DEV_UNBOUND)
856                 value = -ENOENT;
857         else if (data->state == STATE_EP_DISABLED) {
858                 value = 0;
859                 data->state = STATE_EP_READY;
860                 get_ep (data);
861                 fd->private_data = data;
862                 VDEBUG (data->dev, "%s ready\n", data->name);
863         } else
864                 DBG (data->dev, "%s state %d\n",
865                         data->name, data->state);
866         spin_unlock_irq (&data->dev->lock);
867         up (&data->lock);
868         return value;
869 }
870
871 /* used before endpoint configuration */
872 static struct file_operations ep_config_operations = {
873         .owner =        THIS_MODULE,
874         .llseek =       no_llseek,
875
876         .open =         ep_open,
877         .write =        ep_config,
878         .release =      ep_release,
879 };
880
881 /*----------------------------------------------------------------------*/
882
883 /* EP0 IMPLEMENTATION can be partly in userspace.
884  *
885  * Drivers that use this facility receive various events, including
886  * control requests the kernel doesn't handle.  Drivers that don't
887  * use this facility may be too simple-minded for real applications.
888  */
889
890 static inline void ep0_readable (struct dev_data *dev)
891 {
892         wake_up (&dev->wait);
893         kill_fasync (&dev->fasync, SIGIO, POLL_IN);
894 }
895
896 static void clean_req (struct usb_ep *ep, struct usb_request *req)
897 {
898         struct dev_data         *dev = ep->driver_data;
899
900         if (req->buf != dev->rbuf) {
901                 usb_ep_free_buffer (ep, req->buf, req->dma, req->length);
902                 req->buf = dev->rbuf;
903                 req->dma = DMA_ADDR_INVALID;
904         }
905         req->complete = epio_complete;
906         dev->setup_out_ready = 0;
907 }
908
909 static void ep0_complete (struct usb_ep *ep, struct usb_request *req)
910 {
911         struct dev_data         *dev = ep->driver_data;
912         int                     free = 1;
913
914         /* for control OUT, data must still get to userspace */
915         if (!dev->setup_in) {
916                 dev->setup_out_error = (req->status != 0);
917                 if (!dev->setup_out_error)
918                         free = 0;
919                 dev->setup_out_ready = 1;
920                 ep0_readable (dev);
921         } else if (dev->state == STATE_SETUP)
922                 dev->state = STATE_CONNECTED;
923
924         /* clean up as appropriate */
925         if (free && req->buf != &dev->rbuf)
926                 clean_req (ep, req);
927         req->complete = epio_complete;
928 }
929
930 static int setup_req (struct usb_ep *ep, struct usb_request *req, u16 len)
931 {
932         struct dev_data *dev = ep->driver_data;
933
934         if (dev->setup_out_ready) {
935                 DBG (dev, "ep0 request busy!\n");
936                 return -EBUSY;
937         }
938         if (len > sizeof (dev->rbuf))
939                 req->buf = usb_ep_alloc_buffer (ep, len, &req->dma, GFP_ATOMIC);
940         if (req->buf == 0) {
941                 req->buf = dev->rbuf;
942                 return -ENOMEM;
943         }
944         req->complete = ep0_complete;
945         req->length = len;
946         req->zero = 0;
947         return 0;
948 }
949
950 static ssize_t
951 ep0_read (struct file *fd, char __user *buf, size_t len, loff_t *ptr)
952 {
953         struct dev_data                 *dev = fd->private_data;
954         ssize_t                         retval;
955         enum ep0_state                  state;
956
957         spin_lock_irq (&dev->lock);
958
959         /* report fd mode change before acting on it */
960         if (dev->setup_abort) {
961                 dev->setup_abort = 0;
962                 retval = -EIDRM;
963                 goto done;
964         }
965
966         /* control DATA stage */
967         if ((state = dev->state) == STATE_SETUP) {
968
969                 if (dev->setup_in) {            /* stall IN */
970                         VDEBUG(dev, "ep0in stall\n");
971                         (void) usb_ep_set_halt (dev->gadget->ep0);
972                         retval = -EL2HLT;
973                         dev->state = STATE_CONNECTED;
974
975                 } else if (len == 0) {          /* ack SET_CONFIGURATION etc */
976                         struct usb_ep           *ep = dev->gadget->ep0;
977                         struct usb_request      *req = dev->req;
978
979                         if ((retval = setup_req (ep, req, 0)) == 0)
980                                 retval = usb_ep_queue (ep, req, GFP_ATOMIC);
981                         dev->state = STATE_CONNECTED;
982
983                         /* assume that was SET_CONFIGURATION */
984                         if (dev->current_config) {
985                                 unsigned power;
986 #ifdef  HIGHSPEED
987                                 if (dev->gadget->speed == USB_SPEED_HIGH)
988                                         power = dev->hs_config->bMaxPower;
989                                 else
990 #endif
991                                         power = dev->config->bMaxPower;
992                                 usb_gadget_vbus_draw(dev->gadget, 2 * power);
993                         }
994
995                 } else {                        /* collect OUT data */
996                         if ((fd->f_flags & O_NONBLOCK) != 0
997                                         && !dev->setup_out_ready) {
998                                 retval = -EAGAIN;
999                                 goto done;
1000                         }
1001                         spin_unlock_irq (&dev->lock);
1002                         retval = wait_event_interruptible (dev->wait,
1003                                         dev->setup_out_ready != 0);
1004
1005                         /* FIXME state could change from under us */
1006                         spin_lock_irq (&dev->lock);
1007                         if (retval)
1008                                 goto done;
1009                         if (dev->setup_out_error)
1010                                 retval = -EIO;
1011                         else {
1012                                 len = min (len, (size_t)dev->req->actual);
1013 // FIXME don't call this with the spinlock held ...
1014                                 if (copy_to_user (buf, &dev->req->buf, len))
1015                                         retval = -EFAULT;
1016                                 clean_req (dev->gadget->ep0, dev->req);
1017                                 /* NOTE userspace can't yet choose to stall */
1018                         }
1019                 }
1020                 goto done;
1021         }
1022
1023         /* else normal: return event data */
1024         if (len < sizeof dev->event [0]) {
1025                 retval = -EINVAL;
1026                 goto done;
1027         }
1028         len -= len % sizeof (struct usb_gadgetfs_event);
1029         dev->usermode_setup = 1;
1030
1031 scan:
1032         /* return queued events right away */
1033         if (dev->ev_next != 0) {
1034                 unsigned                i, n;
1035                 int                     tmp = dev->ev_next;
1036
1037                 len = min (len, tmp * sizeof (struct usb_gadgetfs_event));
1038                 n = len / sizeof (struct usb_gadgetfs_event);
1039
1040                 /* ep0 can't deliver events when STATE_SETUP */
1041                 for (i = 0; i < n; i++) {
1042                         if (dev->event [i].type == GADGETFS_SETUP) {
1043                                 len = n = i + 1;
1044                                 len *= sizeof (struct usb_gadgetfs_event);
1045                                 n = 0;
1046                                 break;
1047                         }
1048                 }
1049                 spin_unlock_irq (&dev->lock);
1050                 if (copy_to_user (buf, &dev->event, len))
1051                         retval = -EFAULT;
1052                 else
1053                         retval = len;
1054                 if (len > 0) {
1055                         len /= sizeof (struct usb_gadgetfs_event);
1056
1057                         /* NOTE this doesn't guard against broken drivers;
1058                          * concurrent ep0 readers may lose events.
1059                          */
1060                         spin_lock_irq (&dev->lock);
1061                         dev->ev_next -= len;
1062                         if (dev->ev_next != 0)
1063                                 memmove (&dev->event, &dev->event [len],
1064                                         sizeof (struct usb_gadgetfs_event)
1065                                                 * (tmp - len));
1066                         if (n == 0)
1067                                 dev->state = STATE_SETUP;
1068                         spin_unlock_irq (&dev->lock);
1069                 }
1070                 return retval;
1071         }
1072         if (fd->f_flags & O_NONBLOCK) {
1073                 retval = -EAGAIN;
1074                 goto done;
1075         }
1076
1077         switch (state) {
1078         default:
1079                 DBG (dev, "fail %s, state %d\n", __FUNCTION__, state);
1080                 retval = -ESRCH;
1081                 break;
1082         case STATE_UNCONNECTED:
1083         case STATE_CONNECTED:
1084                 spin_unlock_irq (&dev->lock);
1085                 DBG (dev, "%s wait\n", __FUNCTION__);
1086
1087                 /* wait for events */
1088                 retval = wait_event_interruptible (dev->wait,
1089                                 dev->ev_next != 0);
1090                 if (retval < 0)
1091                         return retval;
1092                 spin_lock_irq (&dev->lock);
1093                 goto scan;
1094         }
1095
1096 done:
1097         spin_unlock_irq (&dev->lock);
1098         return retval;
1099 }
1100
1101 static struct usb_gadgetfs_event *
1102 next_event (struct dev_data *dev, enum usb_gadgetfs_event_type type)
1103 {
1104         struct usb_gadgetfs_event       *event;
1105         unsigned                        i;
1106
1107         switch (type) {
1108         /* these events purge the queue */
1109         case GADGETFS_DISCONNECT:
1110                 if (dev->state == STATE_SETUP)
1111                         dev->setup_abort = 1;
1112                 // FALL THROUGH
1113         case GADGETFS_CONNECT:
1114                 dev->ev_next = 0;
1115                 break;
1116         case GADGETFS_SETUP:            /* previous request timed out */
1117         case GADGETFS_SUSPEND:          /* same effect */
1118                 /* these events can't be repeated */
1119                 for (i = 0; i != dev->ev_next; i++) {
1120                         if (dev->event [i].type != type)
1121                                 continue;
1122                         DBG (dev, "discard old event %d\n", type);
1123                         dev->ev_next--;
1124                         if (i == dev->ev_next)
1125                                 break;
1126                         /* indices start at zero, for simplicity */
1127                         memmove (&dev->event [i], &dev->event [i + 1],
1128                                 sizeof (struct usb_gadgetfs_event)
1129                                         * (dev->ev_next - i));
1130                 }
1131                 break;
1132         default:
1133                 BUG ();
1134         }
1135         event = &dev->event [dev->ev_next++];
1136         BUG_ON (dev->ev_next > N_EVENT);
1137         VDEBUG (dev, "ev %d, next %d\n", type, dev->ev_next);
1138         memset (event, 0, sizeof *event);
1139         event->type = type;
1140         return event;
1141 }
1142
1143 static ssize_t
1144 ep0_write (struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
1145 {
1146         struct dev_data         *dev = fd->private_data;
1147         ssize_t                 retval = -ESRCH;
1148
1149         spin_lock_irq (&dev->lock);
1150
1151         /* report fd mode change before acting on it */
1152         if (dev->setup_abort) {
1153                 dev->setup_abort = 0;
1154                 retval = -EIDRM;
1155
1156         /* data and/or status stage for control request */
1157         } else if (dev->state == STATE_SETUP) {
1158
1159                 /* IN DATA+STATUS caller makes len <= wLength */
1160                 if (dev->setup_in) {
1161                         retval = setup_req (dev->gadget->ep0, dev->req, len);
1162                         if (retval == 0) {
1163                                 spin_unlock_irq (&dev->lock);
1164                                 if (copy_from_user (dev->req->buf, buf, len))
1165                                         retval = -EFAULT;
1166                                 else {
1167                                         if (len < dev->setup_wLength)
1168                                                 dev->req->zero = 1;
1169                                         retval = usb_ep_queue (
1170                                                 dev->gadget->ep0, dev->req,
1171                                                 GFP_KERNEL);
1172                                 }
1173                                 if (retval < 0) {
1174                                         spin_lock_irq (&dev->lock);
1175                                         clean_req (dev->gadget->ep0, dev->req);
1176                                         spin_unlock_irq (&dev->lock);
1177                                 } else
1178                                         retval = len;
1179
1180                                 return retval;
1181                         }
1182
1183                 /* can stall some OUT transfers */
1184                 } else if (dev->setup_can_stall) {
1185                         VDEBUG(dev, "ep0out stall\n");
1186                         (void) usb_ep_set_halt (dev->gadget->ep0);
1187                         retval = -EL2HLT;
1188                         dev->state = STATE_CONNECTED;
1189                 } else {
1190                         DBG(dev, "bogus ep0out stall!\n");
1191                 }
1192         } else
1193                 DBG (dev, "fail %s, state %d\n", __FUNCTION__, dev->state);
1194
1195         spin_unlock_irq (&dev->lock);
1196         return retval;
1197 }
1198
1199 static int
1200 ep0_fasync (int f, struct file *fd, int on)
1201 {
1202         struct dev_data         *dev = fd->private_data;
1203         // caller must F_SETOWN before signal delivery happens
1204         VDEBUG (dev, "%s %s\n", __FUNCTION__, on ? "on" : "off");
1205         return fasync_helper (f, fd, on, &dev->fasync);
1206 }
1207
1208 static struct usb_gadget_driver gadgetfs_driver;
1209
1210 static int
1211 dev_release (struct inode *inode, struct file *fd)
1212 {
1213         struct dev_data         *dev = fd->private_data;
1214
1215         /* closing ep0 === shutdown all */
1216
1217         usb_gadget_unregister_driver (&gadgetfs_driver);
1218
1219         /* at this point "good" hardware has disconnected the
1220          * device from USB; the host won't see it any more.
1221          * alternatively, all host requests will time out.
1222          */
1223
1224         fasync_helper (-1, fd, 0, &dev->fasync);
1225         kfree (dev->buf);
1226         dev->buf = NULL;
1227         put_dev (dev);
1228
1229         /* other endpoints were all decoupled from this device */
1230         dev->state = STATE_DEV_DISABLED;
1231         return 0;
1232 }
1233
1234 static int dev_ioctl (struct inode *inode, struct file *fd,
1235                 unsigned code, unsigned long value)
1236 {
1237         struct dev_data         *dev = fd->private_data;
1238         struct usb_gadget       *gadget = dev->gadget;
1239
1240         if (gadget->ops->ioctl)
1241                 return gadget->ops->ioctl (gadget, code, value);
1242         return -ENOTTY;
1243 }
1244
1245 /* used after device configuration */
1246 static struct file_operations ep0_io_operations = {
1247         .owner =        THIS_MODULE,
1248         .llseek =       no_llseek,
1249
1250         .read =         ep0_read,
1251         .write =        ep0_write,
1252         .fasync =       ep0_fasync,
1253         // .poll =      ep0_poll,
1254         .ioctl =        dev_ioctl,
1255         .release =      dev_release,
1256 };
1257
1258 /*----------------------------------------------------------------------*/
1259
1260 /* The in-kernel gadget driver handles most ep0 issues, in particular
1261  * enumerating the single configuration (as provided from user space).
1262  *
1263  * Unrecognized ep0 requests may be handled in user space.
1264  */
1265
1266 #ifdef  HIGHSPEED
1267 static void make_qualifier (struct dev_data *dev)
1268 {
1269         struct usb_qualifier_descriptor         qual;
1270         struct usb_device_descriptor            *desc;
1271
1272         qual.bLength = sizeof qual;
1273         qual.bDescriptorType = USB_DT_DEVICE_QUALIFIER;
1274         qual.bcdUSB = __constant_cpu_to_le16 (0x0200);
1275
1276         desc = dev->dev;
1277         qual.bDeviceClass = desc->bDeviceClass;
1278         qual.bDeviceSubClass = desc->bDeviceSubClass;
1279         qual.bDeviceProtocol = desc->bDeviceProtocol;
1280
1281         /* assumes ep0 uses the same value for both speeds ... */
1282         qual.bMaxPacketSize0 = desc->bMaxPacketSize0;
1283
1284         qual.bNumConfigurations = 1;
1285         qual.bRESERVED = 0;
1286
1287         memcpy (dev->rbuf, &qual, sizeof qual);
1288 }
1289 #endif
1290
1291 static int
1292 config_buf (struct dev_data *dev, u8 type, unsigned index)
1293 {
1294         int             len;
1295 #ifdef HIGHSPEED
1296         int             hs;
1297 #endif
1298
1299         /* only one configuration */
1300         if (index > 0)
1301                 return -EINVAL;
1302
1303 #ifdef HIGHSPEED
1304         hs = (dev->gadget->speed == USB_SPEED_HIGH);
1305         if (type == USB_DT_OTHER_SPEED_CONFIG)
1306                 hs = !hs;
1307         if (hs) {
1308                 dev->req->buf = dev->hs_config;
1309                 len = le16_to_cpup (&dev->hs_config->wTotalLength);
1310         } else
1311 #endif
1312         {
1313                 dev->req->buf = dev->config;
1314                 len = le16_to_cpup (&dev->config->wTotalLength);
1315         }
1316         ((u8 *)dev->req->buf) [1] = type;
1317         return len;
1318 }
1319
1320 static int
1321 gadgetfs_setup (struct usb_gadget *gadget, const struct usb_ctrlrequest *ctrl)
1322 {
1323         struct dev_data                 *dev = get_gadget_data (gadget);
1324         struct usb_request              *req = dev->req;
1325         int                             value = -EOPNOTSUPP;
1326         struct usb_gadgetfs_event       *event;
1327         u16                             w_value = le16_to_cpu(ctrl->wValue);
1328         u16                             w_length = le16_to_cpu(ctrl->wLength);
1329
1330         spin_lock (&dev->lock);
1331         dev->setup_abort = 0;
1332         if (dev->state == STATE_UNCONNECTED) {
1333                 struct usb_ep   *ep;
1334                 struct ep_data  *data;
1335
1336                 dev->state = STATE_CONNECTED;
1337                 dev->dev->bMaxPacketSize0 = gadget->ep0->maxpacket;
1338
1339 #ifdef  HIGHSPEED
1340                 if (gadget->speed == USB_SPEED_HIGH && dev->hs_config == 0) {
1341                         ERROR (dev, "no high speed config??\n");
1342                         return -EINVAL;
1343                 }
1344 #endif  /* HIGHSPEED */
1345
1346                 INFO (dev, "connected\n");
1347                 event = next_event (dev, GADGETFS_CONNECT);
1348                 event->u.speed = gadget->speed;
1349                 ep0_readable (dev);
1350
1351                 list_for_each_entry (ep, &gadget->ep_list, ep_list) {
1352                         data = ep->driver_data;
1353                         /* ... down_trylock (&data->lock) ... */
1354                         if (data->state != STATE_EP_DEFER_ENABLE)
1355                                 continue;
1356 #ifdef  HIGHSPEED
1357                         if (gadget->speed == USB_SPEED_HIGH)
1358                                 value = usb_ep_enable (ep, &data->hs_desc);
1359                         else
1360 #endif  /* HIGHSPEED */
1361                                 value = usb_ep_enable (ep, &data->desc);
1362                         if (value) {
1363                                 ERROR (dev, "deferred %s enable --> %d\n",
1364                                         data->name, value);
1365                                 continue;
1366                         }
1367                         data->state = STATE_EP_ENABLED;
1368                         wake_up (&data->wait);
1369                         DBG (dev, "woke up %s waiters\n", data->name);
1370                 }
1371
1372         /* host may have given up waiting for response.  we can miss control
1373          * requests handled lower down (device/endpoint status and features);
1374          * then ep0_{read,write} will report the wrong status. controller
1375          * driver will have aborted pending i/o.
1376          */
1377         } else if (dev->state == STATE_SETUP)
1378                 dev->setup_abort = 1;
1379
1380         req->buf = dev->rbuf;
1381         req->dma = DMA_ADDR_INVALID;
1382         req->context = NULL;
1383         value = -EOPNOTSUPP;
1384         switch (ctrl->bRequest) {
1385
1386         case USB_REQ_GET_DESCRIPTOR:
1387                 if (ctrl->bRequestType != USB_DIR_IN)
1388                         goto unrecognized;
1389                 switch (w_value >> 8) {
1390
1391                 case USB_DT_DEVICE:
1392                         value = min (w_length, (u16) sizeof *dev->dev);
1393                         req->buf = dev->dev;
1394                         break;
1395 #ifdef  HIGHSPEED
1396                 case USB_DT_DEVICE_QUALIFIER:
1397                         if (!dev->hs_config)
1398                                 break;
1399                         value = min (w_length, (u16)
1400                                 sizeof (struct usb_qualifier_descriptor));
1401                         make_qualifier (dev);
1402                         break;
1403                 case USB_DT_OTHER_SPEED_CONFIG:
1404                         // FALLTHROUGH
1405 #endif
1406                 case USB_DT_CONFIG:
1407                         value = config_buf (dev,
1408                                         w_value >> 8,
1409                                         w_value & 0xff);
1410                         if (value >= 0)
1411                                 value = min (w_length, (u16) value);
1412                         break;
1413                 case USB_DT_STRING:
1414                         goto unrecognized;
1415
1416                 default:                // all others are errors
1417                         break;
1418                 }
1419                 break;
1420
1421         /* currently one config, two speeds */
1422         case USB_REQ_SET_CONFIGURATION:
1423                 if (ctrl->bRequestType != 0)
1424                         break;
1425                 if (0 == (u8) w_value) {
1426                         value = 0;
1427                         dev->current_config = 0;
1428                         usb_gadget_vbus_draw(gadget, 8 /* mA */ );
1429                         // user mode expected to disable endpoints
1430                 } else {
1431                         u8      config, power;
1432 #ifdef  HIGHSPEED
1433                         if (gadget->speed == USB_SPEED_HIGH) {
1434                                 config = dev->hs_config->bConfigurationValue;
1435                                 power = dev->hs_config->bMaxPower;
1436                         } else
1437 #endif
1438                         {
1439                                 config = dev->config->bConfigurationValue;
1440                                 power = dev->config->bMaxPower;
1441                         }
1442
1443                         if (config == (u8) w_value) {
1444                                 value = 0;
1445                                 dev->current_config = config;
1446                                 usb_gadget_vbus_draw(gadget, 2 * power);
1447                         }
1448                 }
1449
1450                 /* report SET_CONFIGURATION like any other control request,
1451                  * except that usermode may not stall this.  the next
1452                  * request mustn't be allowed start until this finishes:
1453                  * endpoints and threads set up, etc.
1454                  *
1455                  * NOTE:  older PXA hardware (before PXA 255: without UDCCFR)
1456                  * has bad/racey automagic that prevents synchronizing here.
1457                  * even kernel mode drivers often miss them.
1458                  */
1459                 if (value == 0) {
1460                         INFO (dev, "configuration #%d\n", dev->current_config);
1461                         if (dev->usermode_setup) {
1462                                 dev->setup_can_stall = 0;
1463                                 goto delegate;
1464                         }
1465                 }
1466                 break;
1467
1468 #ifndef CONFIG_USB_GADGETFS_PXA2XX
1469         /* PXA automagically handles this request too */
1470         case USB_REQ_GET_CONFIGURATION:
1471                 if (ctrl->bRequestType != 0x80)
1472                         break;
1473                 *(u8 *)req->buf = dev->current_config;
1474                 value = min (w_length, (u16) 1);
1475                 break;
1476 #endif
1477
1478         default:
1479 unrecognized:
1480                 VDEBUG (dev, "%s req%02x.%02x v%04x i%04x l%d\n",
1481                         dev->usermode_setup ? "delegate" : "fail",
1482                         ctrl->bRequestType, ctrl->bRequest,
1483                         w_value, le16_to_cpu(ctrl->wIndex), w_length);
1484
1485                 /* if there's an ep0 reader, don't stall */
1486                 if (dev->usermode_setup) {
1487                         dev->setup_can_stall = 1;
1488 delegate:
1489                         dev->setup_in = (ctrl->bRequestType & USB_DIR_IN)
1490                                                 ? 1 : 0;
1491                         dev->setup_wLength = w_length;
1492                         dev->setup_out_ready = 0;
1493                         dev->setup_out_error = 0;
1494                         value = 0;
1495
1496                         /* read DATA stage for OUT right away */
1497                         if (unlikely (!dev->setup_in && w_length)) {
1498                                 value = setup_req (gadget->ep0, dev->req,
1499                                                         w_length);
1500                                 if (value < 0)
1501                                         break;
1502                                 value = usb_ep_queue (gadget->ep0, dev->req,
1503                                                         GFP_ATOMIC);
1504                                 if (value < 0) {
1505                                         clean_req (gadget->ep0, dev->req);
1506                                         break;
1507                                 }
1508
1509                                 /* we can't currently stall these */
1510                                 dev->setup_can_stall = 0;
1511                         }
1512
1513                         /* state changes when reader collects event */
1514                         event = next_event (dev, GADGETFS_SETUP);
1515                         event->u.setup = *ctrl;
1516                         ep0_readable (dev);
1517                         spin_unlock (&dev->lock);
1518                         return 0;
1519                 }
1520         }
1521
1522         /* proceed with data transfer and status phases? */
1523         if (value >= 0 && dev->state != STATE_SETUP) {
1524                 req->length = value;
1525                 req->zero = value < w_length;
1526                 value = usb_ep_queue (gadget->ep0, req, GFP_ATOMIC);
1527                 if (value < 0) {
1528                         DBG (dev, "ep_queue --> %d\n", value);
1529                         req->status = 0;
1530                 }
1531         }
1532
1533         /* device stalls when value < 0 */
1534         spin_unlock (&dev->lock);
1535         return value;
1536 }
1537
1538 static void destroy_ep_files (struct dev_data *dev)
1539 {
1540         struct list_head        *entry, *tmp;
1541
1542         DBG (dev, "%s %d\n", __FUNCTION__, dev->state);
1543
1544         /* dev->state must prevent interference */
1545 restart:
1546         spin_lock_irq (&dev->lock);
1547         list_for_each_safe (entry, tmp, &dev->epfiles) {
1548                 struct ep_data  *ep;
1549                 struct inode    *parent;
1550                 struct dentry   *dentry;
1551
1552                 /* break link to FS */
1553                 ep = list_entry (entry, struct ep_data, epfiles);
1554                 list_del_init (&ep->epfiles);
1555                 dentry = ep->dentry;
1556                 ep->dentry = NULL;
1557                 parent = dentry->d_parent->d_inode;
1558
1559                 /* break link to controller */
1560                 if (ep->state == STATE_EP_ENABLED)
1561                         (void) usb_ep_disable (ep->ep);
1562                 ep->state = STATE_EP_UNBOUND;
1563                 usb_ep_free_request (ep->ep, ep->req);
1564                 ep->ep = NULL;
1565                 wake_up (&ep->wait);
1566                 put_ep (ep);
1567
1568                 spin_unlock_irq (&dev->lock);
1569
1570                 /* break link to dcache */
1571                 mutex_lock (&parent->i_mutex);
1572                 d_delete (dentry);
1573                 dput (dentry);
1574                 mutex_unlock (&parent->i_mutex);
1575
1576                 /* fds may still be open */
1577                 goto restart;
1578         }
1579         spin_unlock_irq (&dev->lock);
1580 }
1581
1582
1583 static struct inode *
1584 gadgetfs_create_file (struct super_block *sb, char const *name,
1585                 void *data, struct file_operations *fops,
1586                 struct dentry **dentry_p);
1587
1588 static int activate_ep_files (struct dev_data *dev)
1589 {
1590         struct usb_ep   *ep;
1591
1592         gadget_for_each_ep (ep, dev->gadget) {
1593                 struct ep_data  *data;
1594
1595                 data = kmalloc (sizeof *data, GFP_KERNEL);
1596                 if (!data)
1597                         goto enomem;
1598                 memset (data, 0, sizeof data);
1599                 data->state = STATE_EP_DISABLED;
1600                 init_MUTEX (&data->lock);
1601                 init_waitqueue_head (&data->wait);
1602
1603                 strncpy (data->name, ep->name, sizeof (data->name) - 1);
1604                 atomic_set (&data->count, 1);
1605                 data->dev = dev;
1606                 get_dev (dev);
1607
1608                 data->ep = ep;
1609                 ep->driver_data = data;
1610
1611                 data->req = usb_ep_alloc_request (ep, GFP_KERNEL);
1612                 if (!data->req)
1613                         goto enomem;
1614
1615                 data->inode = gadgetfs_create_file (dev->sb, data->name,
1616                                 data, &ep_config_operations,
1617                                 &data->dentry);
1618                 if (!data->inode) {
1619                         kfree (data);
1620                         goto enomem;
1621                 }
1622                 list_add_tail (&data->epfiles, &dev->epfiles);
1623         }
1624         return 0;
1625
1626 enomem:
1627         DBG (dev, "%s enomem\n", __FUNCTION__);
1628         destroy_ep_files (dev);
1629         return -ENOMEM;
1630 }
1631
1632 static void
1633 gadgetfs_unbind (struct usb_gadget *gadget)
1634 {
1635         struct dev_data         *dev = get_gadget_data (gadget);
1636
1637         DBG (dev, "%s\n", __FUNCTION__);
1638
1639         spin_lock_irq (&dev->lock);
1640         dev->state = STATE_DEV_UNBOUND;
1641         spin_unlock_irq (&dev->lock);
1642
1643         destroy_ep_files (dev);
1644         gadget->ep0->driver_data = NULL;
1645         set_gadget_data (gadget, NULL);
1646
1647         /* we've already been disconnected ... no i/o is active */
1648         if (dev->req)
1649                 usb_ep_free_request (gadget->ep0, dev->req);
1650         DBG (dev, "%s done\n", __FUNCTION__);
1651         put_dev (dev);
1652 }
1653
1654 static struct dev_data          *the_device;
1655
1656 static int
1657 gadgetfs_bind (struct usb_gadget *gadget)
1658 {
1659         struct dev_data         *dev = the_device;
1660
1661         if (!dev)
1662                 return -ESRCH;
1663         if (0 != strcmp (CHIP, gadget->name)) {
1664                 printk (KERN_ERR "%s expected %s controller not %s\n",
1665                         shortname, CHIP, gadget->name);
1666                 return -ENODEV;
1667         }
1668
1669         set_gadget_data (gadget, dev);
1670         dev->gadget = gadget;
1671         gadget->ep0->driver_data = dev;
1672         dev->dev->bMaxPacketSize0 = gadget->ep0->maxpacket;
1673
1674         /* preallocate control response and buffer */
1675         dev->req = usb_ep_alloc_request (gadget->ep0, GFP_KERNEL);
1676         if (!dev->req)
1677                 goto enomem;
1678         dev->req->context = NULL;
1679         dev->req->complete = epio_complete;
1680
1681         if (activate_ep_files (dev) < 0)
1682                 goto enomem;
1683
1684         INFO (dev, "bound to %s driver\n", gadget->name);
1685         dev->state = STATE_UNCONNECTED;
1686         get_dev (dev);
1687         return 0;
1688
1689 enomem:
1690         gadgetfs_unbind (gadget);
1691         return -ENOMEM;
1692 }
1693
1694 static void
1695 gadgetfs_disconnect (struct usb_gadget *gadget)
1696 {
1697         struct dev_data         *dev = get_gadget_data (gadget);
1698
1699         if (dev->state == STATE_UNCONNECTED) {
1700                 DBG (dev, "already unconnected\n");
1701                 return;
1702         }
1703         dev->state = STATE_UNCONNECTED;
1704
1705         INFO (dev, "disconnected\n");
1706         spin_lock (&dev->lock);
1707         next_event (dev, GADGETFS_DISCONNECT);
1708         ep0_readable (dev);
1709         spin_unlock (&dev->lock);
1710 }
1711
1712 static void
1713 gadgetfs_suspend (struct usb_gadget *gadget)
1714 {
1715         struct dev_data         *dev = get_gadget_data (gadget);
1716
1717         INFO (dev, "suspended from state %d\n", dev->state);
1718         spin_lock (&dev->lock);
1719         switch (dev->state) {
1720         case STATE_SETUP:               // VERY odd... host died??
1721         case STATE_CONNECTED:
1722         case STATE_UNCONNECTED:
1723                 next_event (dev, GADGETFS_SUSPEND);
1724                 ep0_readable (dev);
1725                 /* FALLTHROUGH */
1726         default:
1727                 break;
1728         }
1729         spin_unlock (&dev->lock);
1730 }
1731
1732 static struct usb_gadget_driver gadgetfs_driver = {
1733 #ifdef  HIGHSPEED
1734         .speed          = USB_SPEED_HIGH,
1735 #else
1736         .speed          = USB_SPEED_FULL,
1737 #endif
1738         .function       = (char *) driver_desc,
1739         .bind           = gadgetfs_bind,
1740         .unbind         = gadgetfs_unbind,
1741         .setup          = gadgetfs_setup,
1742         .disconnect     = gadgetfs_disconnect,
1743         .suspend        = gadgetfs_suspend,
1744
1745         .driver         = {
1746                 .name           = (char *) shortname,
1747         },
1748 };
1749
1750 /*----------------------------------------------------------------------*/
1751
1752 static void gadgetfs_nop(struct usb_gadget *arg) { }
1753
1754 static int gadgetfs_probe (struct usb_gadget *gadget)
1755 {
1756         CHIP = gadget->name;
1757         return -EISNAM;
1758 }
1759
1760 static struct usb_gadget_driver probe_driver = {
1761         .speed          = USB_SPEED_HIGH,
1762         .bind           = gadgetfs_probe,
1763         .unbind         = gadgetfs_nop,
1764         .setup          = (void *)gadgetfs_nop,
1765         .disconnect     = gadgetfs_nop,
1766         .driver         = {
1767                 .name           = "nop",
1768         },
1769 };
1770
1771
1772 /* DEVICE INITIALIZATION
1773  *
1774  *     fd = open ("/dev/gadget/$CHIP", O_RDWR)
1775  *     status = write (fd, descriptors, sizeof descriptors)
1776  *
1777  * That write establishes the device configuration, so the kernel can
1778  * bind to the controller ... guaranteeing it can handle enumeration
1779  * at all necessary speeds.  Descriptor order is:
1780  *
1781  * . message tag (u32, host order) ... for now, must be zero; it
1782  *      would change to support features like multi-config devices
1783  * . full/low speed config ... all wTotalLength bytes (with interface,
1784  *      class, altsetting, endpoint, and other descriptors)
1785  * . high speed config ... all descriptors, for high speed operation;
1786  *      this one's optional except for high-speed hardware
1787  * . device descriptor
1788  *
1789  * Endpoints are not yet enabled. Drivers may want to immediately
1790  * initialize them, using the /dev/gadget/ep* files that are available
1791  * as soon as the kernel sees the configuration, or they can wait
1792  * until device configuration and interface altsetting changes create
1793  * the need to configure (or unconfigure) them.
1794  *
1795  * After initialization, the device stays active for as long as that
1796  * $CHIP file is open.  Events may then be read from that descriptor,
1797  * such configuration notifications.  More complex drivers will handle
1798  * some control requests in user space.
1799  */
1800
1801 static int is_valid_config (struct usb_config_descriptor *config)
1802 {
1803         return config->bDescriptorType == USB_DT_CONFIG
1804                 && config->bLength == USB_DT_CONFIG_SIZE
1805                 && config->bConfigurationValue != 0
1806                 && (config->bmAttributes & USB_CONFIG_ATT_ONE) != 0
1807                 && (config->bmAttributes & USB_CONFIG_ATT_WAKEUP) == 0;
1808         /* FIXME if gadget->is_otg, _must_ include an otg descriptor */
1809         /* FIXME check lengths: walk to end */
1810 }
1811
1812 static ssize_t
1813 dev_config (struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
1814 {
1815         struct dev_data         *dev = fd->private_data;
1816         ssize_t                 value = len, length = len;
1817         unsigned                total;
1818         u32                     tag;
1819         char                    *kbuf;
1820
1821         if (dev->state != STATE_OPENED)
1822                 return -EEXIST;
1823
1824         if (len < (USB_DT_CONFIG_SIZE + USB_DT_DEVICE_SIZE + 4))
1825                 return -EINVAL;
1826
1827         /* we might need to change message format someday */
1828         if (copy_from_user (&tag, buf, 4))
1829                 return -EFAULT;
1830         if (tag != 0)
1831                 return -EINVAL;
1832         buf += 4;
1833         length -= 4;
1834
1835         kbuf = kmalloc (length, SLAB_KERNEL);
1836         if (!kbuf)
1837                 return -ENOMEM;
1838         if (copy_from_user (kbuf, buf, length)) {
1839                 kfree (kbuf);
1840                 return -EFAULT;
1841         }
1842
1843         spin_lock_irq (&dev->lock);
1844         value = -EINVAL;
1845         if (dev->buf)
1846                 goto fail;
1847         dev->buf = kbuf;
1848
1849         /* full or low speed config */
1850         dev->config = (void *) kbuf;
1851         total = le16_to_cpup (&dev->config->wTotalLength);
1852         if (!is_valid_config (dev->config) || total >= length)
1853                 goto fail;
1854         kbuf += total;
1855         length -= total;
1856
1857         /* optional high speed config */
1858         if (kbuf [1] == USB_DT_CONFIG) {
1859                 dev->hs_config = (void *) kbuf;
1860                 total = le16_to_cpup (&dev->hs_config->wTotalLength);
1861                 if (!is_valid_config (dev->hs_config) || total >= length)
1862                         goto fail;
1863                 kbuf += total;
1864                 length -= total;
1865         }
1866
1867         /* could support multiple configs, using another encoding! */
1868
1869         /* device descriptor (tweaked for paranoia) */
1870         if (length != USB_DT_DEVICE_SIZE)
1871                 goto fail;
1872         dev->dev = (void *)kbuf;
1873         if (dev->dev->bLength != USB_DT_DEVICE_SIZE
1874                         || dev->dev->bDescriptorType != USB_DT_DEVICE
1875                         || dev->dev->bNumConfigurations != 1)
1876                 goto fail;
1877         dev->dev->bNumConfigurations = 1;
1878         dev->dev->bcdUSB = __constant_cpu_to_le16 (0x0200);
1879
1880         /* triggers gadgetfs_bind(); then we can enumerate. */
1881         spin_unlock_irq (&dev->lock);
1882         value = usb_gadget_register_driver (&gadgetfs_driver);
1883         if (value != 0) {
1884                 kfree (dev->buf);
1885                 dev->buf = NULL;
1886         } else {
1887                 /* at this point "good" hardware has for the first time
1888                  * let the USB the host see us.  alternatively, if users
1889                  * unplug/replug that will clear all the error state.
1890                  *
1891                  * note:  everything running before here was guaranteed
1892                  * to choke driver model style diagnostics.  from here
1893                  * on, they can work ... except in cleanup paths that
1894                  * kick in after the ep0 descriptor is closed.
1895                  */
1896                 fd->f_op = &ep0_io_operations;
1897                 value = len;
1898         }
1899         return value;
1900
1901 fail:
1902         spin_unlock_irq (&dev->lock);
1903         pr_debug ("%s: %s fail %Zd, %p\n", shortname, __FUNCTION__, value, dev);
1904         kfree (dev->buf);
1905         dev->buf = NULL;
1906         return value;
1907 }
1908
1909 static int
1910 dev_open (struct inode *inode, struct file *fd)
1911 {
1912         struct dev_data         *dev = inode->u.generic_ip;
1913         int                     value = -EBUSY;
1914
1915         if (dev->state == STATE_DEV_DISABLED) {
1916                 dev->ev_next = 0;
1917                 dev->state = STATE_OPENED;
1918                 fd->private_data = dev;
1919                 get_dev (dev);
1920                 value = 0;
1921         }
1922         return value;
1923 }
1924
1925 static struct file_operations dev_init_operations = {
1926         .owner =        THIS_MODULE,
1927         .llseek =       no_llseek,
1928
1929         .open =         dev_open,
1930         .write =        dev_config,
1931         .fasync =       ep0_fasync,
1932         .ioctl =        dev_ioctl,
1933         .release =      dev_release,
1934 };
1935
1936 /*----------------------------------------------------------------------*/
1937
1938 /* FILESYSTEM AND SUPERBLOCK OPERATIONS
1939  *
1940  * Mounting the filesystem creates a controller file, used first for
1941  * device configuration then later for event monitoring.
1942  */
1943
1944
1945 /* FIXME PAM etc could set this security policy without mount options
1946  * if epfiles inherited ownership and permissons from ep0 ...
1947  */
1948
1949 static unsigned default_uid;
1950 static unsigned default_gid;
1951 static unsigned default_perm = S_IRUSR | S_IWUSR;
1952
1953 module_param (default_uid, uint, 0644);
1954 module_param (default_gid, uint, 0644);
1955 module_param (default_perm, uint, 0644);
1956
1957
1958 static struct inode *
1959 gadgetfs_make_inode (struct super_block *sb,
1960                 void *data, struct file_operations *fops,
1961                 int mode)
1962 {
1963         struct inode *inode = new_inode (sb);
1964
1965         if (inode) {
1966                 inode->i_mode = mode;
1967                 inode->i_uid = default_uid;
1968                 inode->i_gid = default_gid;
1969                 inode->i_blksize = PAGE_CACHE_SIZE;
1970                 inode->i_blocks = 0;
1971                 inode->i_atime = inode->i_mtime = inode->i_ctime
1972                                 = CURRENT_TIME;
1973                 inode->u.generic_ip = data;
1974                 inode->i_fop = fops;
1975         }
1976         return inode;
1977 }
1978
1979 /* creates in fs root directory, so non-renamable and non-linkable.
1980  * so inode and dentry are paired, until device reconfig.
1981  */
1982 static struct inode *
1983 gadgetfs_create_file (struct super_block *sb, char const *name,
1984                 void *data, struct file_operations *fops,
1985                 struct dentry **dentry_p)
1986 {
1987         struct dentry   *dentry;
1988         struct inode    *inode;
1989
1990         dentry = d_alloc_name(sb->s_root, name);
1991         if (!dentry)
1992                 return NULL;
1993
1994         inode = gadgetfs_make_inode (sb, data, fops,
1995                         S_IFREG | (default_perm & S_IRWXUGO));
1996         if (!inode) {
1997                 dput(dentry);
1998                 return NULL;
1999         }
2000         d_add (dentry, inode);
2001         *dentry_p = dentry;
2002         return inode;
2003 }
2004
2005 static struct super_operations gadget_fs_operations = {
2006         .statfs =       simple_statfs,
2007         .drop_inode =   generic_delete_inode,
2008 };
2009
2010 static int
2011 gadgetfs_fill_super (struct super_block *sb, void *opts, int silent)
2012 {
2013         struct inode    *inode;
2014         struct dentry   *d;
2015         struct dev_data *dev;
2016
2017         if (the_device)
2018                 return -ESRCH;
2019
2020         /* fake probe to determine $CHIP */
2021         (void) usb_gadget_register_driver (&probe_driver);
2022         if (!CHIP)
2023                 return -ENODEV;
2024
2025         /* superblock */
2026         sb->s_blocksize = PAGE_CACHE_SIZE;
2027         sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
2028         sb->s_magic = GADGETFS_MAGIC;
2029         sb->s_op = &gadget_fs_operations;
2030         sb->s_time_gran = 1;
2031
2032         /* root inode */
2033         inode = gadgetfs_make_inode (sb,
2034                         NULL, &simple_dir_operations,
2035                         S_IFDIR | S_IRUGO | S_IXUGO);
2036         if (!inode)
2037                 return -ENOMEM;
2038         inode->i_op = &simple_dir_inode_operations;
2039         if (!(d = d_alloc_root (inode))) {
2040                 iput (inode);
2041                 return -ENOMEM;
2042         }
2043         sb->s_root = d;
2044
2045         /* the ep0 file is named after the controller we expect;
2046          * user mode code can use it for sanity checks, like we do.
2047          */
2048         dev = dev_new ();
2049         if (!dev)
2050                 return -ENOMEM;
2051
2052         dev->sb = sb;
2053         if (!(inode = gadgetfs_create_file (sb, CHIP,
2054                                 dev, &dev_init_operations,
2055                                 &dev->dentry))) {
2056                 put_dev(dev);
2057                 return -ENOMEM;
2058         }
2059
2060         /* other endpoint files are available after hardware setup,
2061          * from binding to a controller.
2062          */
2063         the_device = dev;
2064         return 0;
2065 }
2066
2067 /* "mount -t gadgetfs path /dev/gadget" ends up here */
2068 static struct super_block *
2069 gadgetfs_get_sb (struct file_system_type *t, int flags,
2070                 const char *path, void *opts)
2071 {
2072         return get_sb_single (t, flags, opts, gadgetfs_fill_super);
2073 }
2074
2075 static void
2076 gadgetfs_kill_sb (struct super_block *sb)
2077 {
2078         kill_litter_super (sb);
2079         if (the_device) {
2080                 put_dev (the_device);
2081                 the_device = NULL;
2082         }
2083 }
2084
2085 /*----------------------------------------------------------------------*/
2086
2087 static struct file_system_type gadgetfs_type = {
2088         .owner          = THIS_MODULE,
2089         .name           = shortname,
2090         .get_sb         = gadgetfs_get_sb,
2091         .kill_sb        = gadgetfs_kill_sb,
2092 };
2093
2094 /*----------------------------------------------------------------------*/
2095
2096 static int __init init (void)
2097 {
2098         int status;
2099
2100         status = register_filesystem (&gadgetfs_type);
2101         if (status == 0)
2102                 pr_info ("%s: %s, version " DRIVER_VERSION "\n",
2103                         shortname, driver_desc);
2104         return status;
2105 }
2106 module_init (init);
2107
2108 static void __exit cleanup (void)
2109 {
2110         pr_debug ("unregister %s\n", shortname);
2111         unregister_filesystem (&gadgetfs_type);
2112 }
2113 module_exit (cleanup);
2114