Merge branch 'pxa-tosa' into pxa
[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 VERBOSE_DEBUG */
24
25 #include <linux/init.h>
26 #include <linux/module.h>
27 #include <linux/fs.h>
28 #include <linux/pagemap.h>
29 #include <linux/uts.h>
30 #include <linux/wait.h>
31 #include <linux/compiler.h>
32 #include <asm/uaccess.h>
33 #include <linux/slab.h>
34 #include <linux/poll.h>
35
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/$CHIP is configured
57  *   (by writing configuration and device descriptors).  Afterwards it
58  *   may serve as a source of device events, used to handle all control
59  *   requests other than basic enumeration.
60  *
61  * - Then, after a SET_CONFIGURATION control request, ep_config() is
62  *   called when each /dev/gadget/ep* file is configured (by writing
63  *   endpoint descriptors).  Afterwards these files are used to write()
64  *   IN data or to read() OUT data.  To halt the endpoint, a "wrong
65  *   direction" request is issued (like reading an IN endpoint).
66  *
67  * Unlike "usbfs" the only ioctl()s are for things that are rare, and maybe
68  * not possible on all hardware.  For example, precise fault handling with
69  * respect to data left in endpoint fifos after aborted operations; or
70  * selective clearing of endpoint halts, to implement SET_INTERFACE.
71  */
72
73 #define DRIVER_DESC     "USB Gadget filesystem"
74 #define DRIVER_VERSION  "24 Aug 2004"
75
76 static const char driver_desc [] = DRIVER_DESC;
77 static const char shortname [] = "gadgetfs";
78
79 MODULE_DESCRIPTION (DRIVER_DESC);
80 MODULE_AUTHOR ("David Brownell");
81 MODULE_LICENSE ("GPL");
82
83
84 /*----------------------------------------------------------------------*/
85
86 #define GADGETFS_MAGIC          0xaee71ee7
87 #define DMA_ADDR_INVALID        (~(dma_addr_t)0)
88
89 /* /dev/gadget/$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_DEV_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_DEV_UNCONNECTED,
108         STATE_DEV_CONNECTED,
109         STATE_DEV_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;          /* P: lock */
124         struct usb_gadgetfs_event       event [N_EVENT];
125         unsigned                        ev_next;
126         struct fasync_struct            *fasync;
127         u8                              current_config;
128
129         /* drivers reading ep0 MUST handle control requests (SETUP)
130          * reported that way; else the host will time out.
131          */
132         unsigned                        usermode_setup : 1,
133                                         setup_in : 1,
134                                         setup_can_stall : 1,
135                                         setup_out_ready : 1,
136                                         setup_out_error : 1,
137                                         setup_abort : 1;
138         unsigned                        setup_wLength;
139
140         /* the rest is basically write-once */
141         struct usb_config_descriptor    *config, *hs_config;
142         struct usb_device_descriptor    *dev;
143         struct usb_request              *req;
144         struct usb_gadget               *gadget;
145         struct list_head                epfiles;
146         void                            *buf;
147         wait_queue_head_t               wait;
148         struct super_block              *sb;
149         struct dentry                   *dentry;
150
151         /* except this scratch i/o buffer for ep0 */
152         u8                              rbuf [256];
153 };
154
155 static inline void get_dev (struct dev_data *data)
156 {
157         atomic_inc (&data->count);
158 }
159
160 static void put_dev (struct dev_data *data)
161 {
162         if (likely (!atomic_dec_and_test (&data->count)))
163                 return;
164         /* needs no more cleanup */
165         BUG_ON (waitqueue_active (&data->wait));
166         kfree (data);
167 }
168
169 static struct dev_data *dev_new (void)
170 {
171         struct dev_data         *dev;
172
173         dev = kzalloc(sizeof(*dev), GFP_KERNEL);
174         if (!dev)
175                 return NULL;
176         dev->state = STATE_DEV_DISABLED;
177         atomic_set (&dev->count, 1);
178         spin_lock_init (&dev->lock);
179         INIT_LIST_HEAD (&dev->epfiles);
180         init_waitqueue_head (&dev->wait);
181         return dev;
182 }
183
184 /*----------------------------------------------------------------------*/
185
186 /* other /dev/gadget/$ENDPOINT files represent endpoints */
187 enum ep_state {
188         STATE_EP_DISABLED = 0,
189         STATE_EP_READY,
190         STATE_EP_ENABLED,
191         STATE_EP_UNBOUND,
192 };
193
194 struct ep_data {
195         struct semaphore                lock;
196         enum ep_state                   state;
197         atomic_t                        count;
198         struct dev_data                 *dev;
199         /* must hold dev->lock before accessing ep or req */
200         struct usb_ep                   *ep;
201         struct usb_request              *req;
202         ssize_t                         status;
203         char                            name [16];
204         struct usb_endpoint_descriptor  desc, hs_desc;
205         struct list_head                epfiles;
206         wait_queue_head_t               wait;
207         struct dentry                   *dentry;
208         struct inode                    *inode;
209 };
210
211 static inline void get_ep (struct ep_data *data)
212 {
213         atomic_inc (&data->count);
214 }
215
216 static void put_ep (struct ep_data *data)
217 {
218         if (likely (!atomic_dec_and_test (&data->count)))
219                 return;
220         put_dev (data->dev);
221         /* needs no more cleanup */
222         BUG_ON (!list_empty (&data->epfiles));
223         BUG_ON (waitqueue_active (&data->wait));
224         kfree (data);
225 }
226
227 /*----------------------------------------------------------------------*/
228
229 /* most "how to use the hardware" policy choices are in userspace:
230  * mapping endpoint roles (which the driver needs) to the capabilities
231  * which the usb controller has.  most of those capabilities are exposed
232  * implicitly, starting with the driver name and then endpoint names.
233  */
234
235 static const char *CHIP;
236
237 /*----------------------------------------------------------------------*/
238
239 /* NOTE:  don't use dev_printk calls before binding to the gadget
240  * at the end of ep0 configuration, or after unbind.
241  */
242
243 /* too wordy: dev_printk(level , &(d)->gadget->dev , fmt , ## args) */
244 #define xprintk(d,level,fmt,args...) \
245         printk(level "%s: " fmt , shortname , ## args)
246
247 #ifdef DEBUG
248 #define DBG(dev,fmt,args...) \
249         xprintk(dev , KERN_DEBUG , fmt , ## args)
250 #else
251 #define DBG(dev,fmt,args...) \
252         do { } while (0)
253 #endif /* DEBUG */
254
255 #ifdef VERBOSE_DEBUG
256 #define VDEBUG  DBG
257 #else
258 #define VDEBUG(dev,fmt,args...) \
259         do { } while (0)
260 #endif /* DEBUG */
261
262 #define ERROR(dev,fmt,args...) \
263         xprintk(dev , KERN_ERR , fmt , ## args)
264 #define WARN(dev,fmt,args...) \
265         xprintk(dev , KERN_WARNING , fmt , ## args)
266 #define INFO(dev,fmt,args...) \
267         xprintk(dev , KERN_INFO , fmt , ## args)
268
269
270 /*----------------------------------------------------------------------*/
271
272 /* SYNCHRONOUS ENDPOINT OPERATIONS (bulk/intr/iso)
273  *
274  * After opening, configure non-control endpoints.  Then use normal
275  * stream read() and write() requests; and maybe ioctl() to get more
276  * precise FIFO status when recovering from cancellation.
277  */
278
279 static void epio_complete (struct usb_ep *ep, struct usb_request *req)
280 {
281         struct ep_data  *epdata = ep->driver_data;
282
283         if (!req->context)
284                 return;
285         if (req->status)
286                 epdata->status = req->status;
287         else
288                 epdata->status = req->actual;
289         complete ((struct completion *)req->context);
290 }
291
292 /* tasklock endpoint, returning when it's connected.
293  * still need dev->lock to use epdata->ep.
294  */
295 static int
296 get_ready_ep (unsigned f_flags, struct ep_data *epdata)
297 {
298         int     val;
299
300         if (f_flags & O_NONBLOCK) {
301                 if (down_trylock (&epdata->lock) != 0)
302                         goto nonblock;
303                 if (epdata->state != STATE_EP_ENABLED) {
304                         up (&epdata->lock);
305 nonblock:
306                         val = -EAGAIN;
307                 } else
308                         val = 0;
309                 return val;
310         }
311
312         if ((val = down_interruptible (&epdata->lock)) < 0)
313                 return val;
314
315         switch (epdata->state) {
316         case STATE_EP_ENABLED:
317                 break;
318         // case STATE_EP_DISABLED:              /* "can't happen" */
319         // case STATE_EP_READY:                 /* "can't happen" */
320         default:                                /* error! */
321                 pr_debug ("%s: ep %p not available, state %d\n",
322                                 shortname, epdata, epdata->state);
323                 // FALLTHROUGH
324         case STATE_EP_UNBOUND:                  /* clean disconnect */
325                 val = -ENODEV;
326                 up (&epdata->lock);
327         }
328         return val;
329 }
330
331 static ssize_t
332 ep_io (struct ep_data *epdata, void *buf, unsigned len)
333 {
334         DECLARE_COMPLETION_ONSTACK (done);
335         int value;
336
337         spin_lock_irq (&epdata->dev->lock);
338         if (likely (epdata->ep != NULL)) {
339                 struct usb_request      *req = epdata->req;
340
341                 req->context = &done;
342                 req->complete = epio_complete;
343                 req->buf = buf;
344                 req->length = len;
345                 value = usb_ep_queue (epdata->ep, req, GFP_ATOMIC);
346         } else
347                 value = -ENODEV;
348         spin_unlock_irq (&epdata->dev->lock);
349
350         if (likely (value == 0)) {
351                 value = wait_event_interruptible (done.wait, done.done);
352                 if (value != 0) {
353                         spin_lock_irq (&epdata->dev->lock);
354                         if (likely (epdata->ep != NULL)) {
355                                 DBG (epdata->dev, "%s i/o interrupted\n",
356                                                 epdata->name);
357                                 usb_ep_dequeue (epdata->ep, epdata->req);
358                                 spin_unlock_irq (&epdata->dev->lock);
359
360                                 wait_event (done.wait, done.done);
361                                 if (epdata->status == -ECONNRESET)
362                                         epdata->status = -EINTR;
363                         } else {
364                                 spin_unlock_irq (&epdata->dev->lock);
365
366                                 DBG (epdata->dev, "endpoint gone\n");
367                                 epdata->status = -ENODEV;
368                         }
369                 }
370                 return epdata->status;
371         }
372         return value;
373 }
374
375
376 /* handle a synchronous OUT bulk/intr/iso transfer */
377 static ssize_t
378 ep_read (struct file *fd, char __user *buf, size_t len, loff_t *ptr)
379 {
380         struct ep_data          *data = fd->private_data;
381         void                    *kbuf;
382         ssize_t                 value;
383
384         if ((value = get_ready_ep (fd->f_flags, data)) < 0)
385                 return value;
386
387         /* halt any endpoint by doing a "wrong direction" i/o call */
388         if (data->desc.bEndpointAddress & USB_DIR_IN) {
389                 if ((data->desc.bmAttributes & USB_ENDPOINT_XFERTYPE_MASK)
390                                 == USB_ENDPOINT_XFER_ISOC)
391                         return -EINVAL;
392                 DBG (data->dev, "%s halt\n", data->name);
393                 spin_lock_irq (&data->dev->lock);
394                 if (likely (data->ep != NULL))
395                         usb_ep_set_halt (data->ep);
396                 spin_unlock_irq (&data->dev->lock);
397                 up (&data->lock);
398                 return -EBADMSG;
399         }
400
401         /* FIXME readahead for O_NONBLOCK and poll(); careful with ZLPs */
402
403         value = -ENOMEM;
404         kbuf = kmalloc (len, GFP_KERNEL);
405         if (unlikely (!kbuf))
406                 goto free1;
407
408         value = ep_io (data, kbuf, len);
409         VDEBUG (data->dev, "%s read %zu OUT, status %d\n",
410                 data->name, len, (int) value);
411         if (value >= 0 && copy_to_user (buf, kbuf, value))
412                 value = -EFAULT;
413
414 free1:
415         up (&data->lock);
416         kfree (kbuf);
417         return value;
418 }
419
420 /* handle a synchronous IN bulk/intr/iso transfer */
421 static ssize_t
422 ep_write (struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
423 {
424         struct ep_data          *data = fd->private_data;
425         void                    *kbuf;
426         ssize_t                 value;
427
428         if ((value = get_ready_ep (fd->f_flags, data)) < 0)
429                 return value;
430
431         /* halt any endpoint by doing a "wrong direction" i/o call */
432         if (!(data->desc.bEndpointAddress & USB_DIR_IN)) {
433                 if ((data->desc.bmAttributes & USB_ENDPOINT_XFERTYPE_MASK)
434                                 == USB_ENDPOINT_XFER_ISOC)
435                         return -EINVAL;
436                 DBG (data->dev, "%s halt\n", data->name);
437                 spin_lock_irq (&data->dev->lock);
438                 if (likely (data->ep != NULL))
439                         usb_ep_set_halt (data->ep);
440                 spin_unlock_irq (&data->dev->lock);
441                 up (&data->lock);
442                 return -EBADMSG;
443         }
444
445         /* FIXME writebehind for O_NONBLOCK and poll(), qlen = 1 */
446
447         value = -ENOMEM;
448         kbuf = kmalloc (len, GFP_KERNEL);
449         if (!kbuf)
450                 goto free1;
451         if (copy_from_user (kbuf, buf, len)) {
452                 value = -EFAULT;
453                 goto free1;
454         }
455
456         value = ep_io (data, kbuf, len);
457         VDEBUG (data->dev, "%s write %zu IN, status %d\n",
458                 data->name, len, (int) value);
459 free1:
460         up (&data->lock);
461         kfree (kbuf);
462         return value;
463 }
464
465 static int
466 ep_release (struct inode *inode, struct file *fd)
467 {
468         struct ep_data          *data = fd->private_data;
469         int value;
470
471         if ((value = down_interruptible(&data->lock)) < 0)
472                 return value;
473
474         /* clean up if this can be reopened */
475         if (data->state != STATE_EP_UNBOUND) {
476                 data->state = STATE_EP_DISABLED;
477                 data->desc.bDescriptorType = 0;
478                 data->hs_desc.bDescriptorType = 0;
479                 usb_ep_disable(data->ep);
480         }
481         up (&data->lock);
482         put_ep (data);
483         return 0;
484 }
485
486 static int ep_ioctl (struct inode *inode, struct file *fd,
487                 unsigned code, unsigned long value)
488 {
489         struct ep_data          *data = fd->private_data;
490         int                     status;
491
492         if ((status = get_ready_ep (fd->f_flags, data)) < 0)
493                 return status;
494
495         spin_lock_irq (&data->dev->lock);
496         if (likely (data->ep != NULL)) {
497                 switch (code) {
498                 case GADGETFS_FIFO_STATUS:
499                         status = usb_ep_fifo_status (data->ep);
500                         break;
501                 case GADGETFS_FIFO_FLUSH:
502                         usb_ep_fifo_flush (data->ep);
503                         break;
504                 case GADGETFS_CLEAR_HALT:
505                         status = usb_ep_clear_halt (data->ep);
506                         break;
507                 default:
508                         status = -ENOTTY;
509                 }
510         } else
511                 status = -ENODEV;
512         spin_unlock_irq (&data->dev->lock);
513         up (&data->lock);
514         return status;
515 }
516
517 /*----------------------------------------------------------------------*/
518
519 /* ASYNCHRONOUS ENDPOINT I/O OPERATIONS (bulk/intr/iso) */
520
521 struct kiocb_priv {
522         struct usb_request      *req;
523         struct ep_data          *epdata;
524         void                    *buf;
525         const struct iovec      *iv;
526         unsigned long           nr_segs;
527         unsigned                actual;
528 };
529
530 static int ep_aio_cancel(struct kiocb *iocb, struct io_event *e)
531 {
532         struct kiocb_priv       *priv = iocb->private;
533         struct ep_data          *epdata;
534         int                     value;
535
536         local_irq_disable();
537         epdata = priv->epdata;
538         // spin_lock(&epdata->dev->lock);
539         kiocbSetCancelled(iocb);
540         if (likely(epdata && epdata->ep && priv->req))
541                 value = usb_ep_dequeue (epdata->ep, priv->req);
542         else
543                 value = -EINVAL;
544         // spin_unlock(&epdata->dev->lock);
545         local_irq_enable();
546
547         aio_put_req(iocb);
548         return value;
549 }
550
551 static ssize_t ep_aio_read_retry(struct kiocb *iocb)
552 {
553         struct kiocb_priv       *priv = iocb->private;
554         ssize_t                 len, total;
555         void                    *to_copy;
556         int                     i;
557
558         /* we "retry" to get the right mm context for this: */
559
560         /* copy stuff into user buffers */
561         total = priv->actual;
562         len = 0;
563         to_copy = priv->buf;
564         for (i=0; i < priv->nr_segs; i++) {
565                 ssize_t this = min((ssize_t)(priv->iv[i].iov_len), total);
566
567                 if (copy_to_user(priv->iv[i].iov_base, to_copy, this)) {
568                         if (len == 0)
569                                 len = -EFAULT;
570                         break;
571                 }
572
573                 total -= this;
574                 len += this;
575                 to_copy += this;
576                 if (total == 0)
577                         break;
578         }
579         kfree(priv->buf);
580         kfree(priv);
581         return len;
582 }
583
584 static void ep_aio_complete(struct usb_ep *ep, struct usb_request *req)
585 {
586         struct kiocb            *iocb = req->context;
587         struct kiocb_priv       *priv = iocb->private;
588         struct ep_data          *epdata = priv->epdata;
589
590         /* lock against disconnect (and ideally, cancel) */
591         spin_lock(&epdata->dev->lock);
592         priv->req = NULL;
593         priv->epdata = NULL;
594
595         /* if this was a write or a read returning no data then we
596          * don't need to copy anything to userspace, so we can
597          * complete the aio request immediately.
598          */
599         if (priv->iv == NULL || unlikely(req->actual == 0)) {
600                 kfree(req->buf);
601                 kfree(priv);
602                 iocb->private = NULL;
603                 /* aio_complete() reports bytes-transferred _and_ faults */
604                 aio_complete(iocb, req->actual ? req->actual : req->status,
605                                 req->status);
606         } else {
607                 /* retry() won't report both; so we hide some faults */
608                 if (unlikely(0 != req->status))
609                         DBG(epdata->dev, "%s fault %d len %d\n",
610                                 ep->name, req->status, req->actual);
611
612                 priv->buf = req->buf;
613                 priv->actual = req->actual;
614                 kick_iocb(iocb);
615         }
616         spin_unlock(&epdata->dev->lock);
617
618         usb_ep_free_request(ep, req);
619         put_ep(epdata);
620 }
621
622 static ssize_t
623 ep_aio_rwtail(
624         struct kiocb    *iocb,
625         char            *buf,
626         size_t          len,
627         struct ep_data  *epdata,
628         const struct iovec *iv,
629         unsigned long   nr_segs
630 )
631 {
632         struct kiocb_priv       *priv;
633         struct usb_request      *req;
634         ssize_t                 value;
635
636         priv = kmalloc(sizeof *priv, GFP_KERNEL);
637         if (!priv) {
638                 value = -ENOMEM;
639 fail:
640                 kfree(buf);
641                 return value;
642         }
643         iocb->private = priv;
644         priv->iv = iv;
645         priv->nr_segs = nr_segs;
646
647         value = get_ready_ep(iocb->ki_filp->f_flags, epdata);
648         if (unlikely(value < 0)) {
649                 kfree(priv);
650                 goto fail;
651         }
652
653         iocb->ki_cancel = ep_aio_cancel;
654         get_ep(epdata);
655         priv->epdata = epdata;
656         priv->actual = 0;
657
658         /* each kiocb is coupled to one usb_request, but we can't
659          * allocate or submit those if the host disconnected.
660          */
661         spin_lock_irq(&epdata->dev->lock);
662         if (likely(epdata->ep)) {
663                 req = usb_ep_alloc_request(epdata->ep, GFP_ATOMIC);
664                 if (likely(req)) {
665                         priv->req = req;
666                         req->buf = buf;
667                         req->length = len;
668                         req->complete = ep_aio_complete;
669                         req->context = iocb;
670                         value = usb_ep_queue(epdata->ep, req, GFP_ATOMIC);
671                         if (unlikely(0 != value))
672                                 usb_ep_free_request(epdata->ep, req);
673                 } else
674                         value = -EAGAIN;
675         } else
676                 value = -ENODEV;
677         spin_unlock_irq(&epdata->dev->lock);
678
679         up(&epdata->lock);
680
681         if (unlikely(value)) {
682                 kfree(priv);
683                 put_ep(epdata);
684         } else
685                 value = (iv ? -EIOCBRETRY : -EIOCBQUEUED);
686         return value;
687 }
688
689 static ssize_t
690 ep_aio_read(struct kiocb *iocb, const struct iovec *iov,
691                 unsigned long nr_segs, loff_t o)
692 {
693         struct ep_data          *epdata = iocb->ki_filp->private_data;
694         char                    *buf;
695
696         if (unlikely(epdata->desc.bEndpointAddress & USB_DIR_IN))
697                 return -EINVAL;
698
699         buf = kmalloc(iocb->ki_left, GFP_KERNEL);
700         if (unlikely(!buf))
701                 return -ENOMEM;
702
703         iocb->ki_retry = ep_aio_read_retry;
704         return ep_aio_rwtail(iocb, buf, iocb->ki_left, epdata, iov, nr_segs);
705 }
706
707 static ssize_t
708 ep_aio_write(struct kiocb *iocb, const struct iovec *iov,
709                 unsigned long nr_segs, loff_t o)
710 {
711         struct ep_data          *epdata = iocb->ki_filp->private_data;
712         char                    *buf;
713         size_t                  len = 0;
714         int                     i = 0;
715
716         if (unlikely(!(epdata->desc.bEndpointAddress & USB_DIR_IN)))
717                 return -EINVAL;
718
719         buf = kmalloc(iocb->ki_left, GFP_KERNEL);
720         if (unlikely(!buf))
721                 return -ENOMEM;
722
723         for (i=0; i < nr_segs; i++) {
724                 if (unlikely(copy_from_user(&buf[len], iov[i].iov_base,
725                                 iov[i].iov_len) != 0)) {
726                         kfree(buf);
727                         return -EFAULT;
728                 }
729                 len += iov[i].iov_len;
730         }
731         return ep_aio_rwtail(iocb, buf, len, epdata, NULL, 0);
732 }
733
734 /*----------------------------------------------------------------------*/
735
736 /* used after endpoint configuration */
737 static const struct file_operations ep_io_operations = {
738         .owner =        THIS_MODULE,
739         .llseek =       no_llseek,
740
741         .read =         ep_read,
742         .write =        ep_write,
743         .ioctl =        ep_ioctl,
744         .release =      ep_release,
745
746         .aio_read =     ep_aio_read,
747         .aio_write =    ep_aio_write,
748 };
749
750 /* ENDPOINT INITIALIZATION
751  *
752  *     fd = open ("/dev/gadget/$ENDPOINT", O_RDWR)
753  *     status = write (fd, descriptors, sizeof descriptors)
754  *
755  * That write establishes the endpoint configuration, configuring
756  * the controller to process bulk, interrupt, or isochronous transfers
757  * at the right maxpacket size, and so on.
758  *
759  * The descriptors are message type 1, identified by a host order u32
760  * at the beginning of what's written.  Descriptor order is: full/low
761  * speed descriptor, then optional high speed descriptor.
762  */
763 static ssize_t
764 ep_config (struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
765 {
766         struct ep_data          *data = fd->private_data;
767         struct usb_ep           *ep;
768         u32                     tag;
769         int                     value, length = len;
770
771         if ((value = down_interruptible (&data->lock)) < 0)
772                 return value;
773
774         if (data->state != STATE_EP_READY) {
775                 value = -EL2HLT;
776                 goto fail;
777         }
778
779         value = len;
780         if (len < USB_DT_ENDPOINT_SIZE + 4)
781                 goto fail0;
782
783         /* we might need to change message format someday */
784         if (copy_from_user (&tag, buf, 4)) {
785                 goto fail1;
786         }
787         if (tag != 1) {
788                 DBG(data->dev, "config %s, bad tag %d\n", data->name, tag);
789                 goto fail0;
790         }
791         buf += 4;
792         len -= 4;
793
794         /* NOTE:  audio endpoint extensions not accepted here;
795          * just don't include the extra bytes.
796          */
797
798         /* full/low speed descriptor, then high speed */
799         if (copy_from_user (&data->desc, buf, USB_DT_ENDPOINT_SIZE)) {
800                 goto fail1;
801         }
802         if (data->desc.bLength != USB_DT_ENDPOINT_SIZE
803                         || data->desc.bDescriptorType != USB_DT_ENDPOINT)
804                 goto fail0;
805         if (len != USB_DT_ENDPOINT_SIZE) {
806                 if (len != 2 * USB_DT_ENDPOINT_SIZE)
807                         goto fail0;
808                 if (copy_from_user (&data->hs_desc, buf + USB_DT_ENDPOINT_SIZE,
809                                         USB_DT_ENDPOINT_SIZE)) {
810                         goto fail1;
811                 }
812                 if (data->hs_desc.bLength != USB_DT_ENDPOINT_SIZE
813                                 || data->hs_desc.bDescriptorType
814                                         != USB_DT_ENDPOINT) {
815                         DBG(data->dev, "config %s, bad hs length or type\n",
816                                         data->name);
817                         goto fail0;
818                 }
819         }
820
821         spin_lock_irq (&data->dev->lock);
822         if (data->dev->state == STATE_DEV_UNBOUND) {
823                 value = -ENOENT;
824                 goto gone;
825         } else if ((ep = data->ep) == NULL) {
826                 value = -ENODEV;
827                 goto gone;
828         }
829         switch (data->dev->gadget->speed) {
830         case USB_SPEED_LOW:
831         case USB_SPEED_FULL:
832                 value = usb_ep_enable (ep, &data->desc);
833                 if (value == 0)
834                         data->state = STATE_EP_ENABLED;
835                 break;
836 #ifdef  CONFIG_USB_GADGET_DUALSPEED
837         case USB_SPEED_HIGH:
838                 /* fails if caller didn't provide that descriptor... */
839                 value = usb_ep_enable (ep, &data->hs_desc);
840                 if (value == 0)
841                         data->state = STATE_EP_ENABLED;
842                 break;
843 #endif
844         default:
845                 DBG(data->dev, "unconnected, %s init abandoned\n",
846                                 data->name);
847                 value = -EINVAL;
848         }
849         if (value == 0) {
850                 fd->f_op = &ep_io_operations;
851                 value = length;
852         }
853 gone:
854         spin_unlock_irq (&data->dev->lock);
855         if (value < 0) {
856 fail:
857                 data->desc.bDescriptorType = 0;
858                 data->hs_desc.bDescriptorType = 0;
859         }
860         up (&data->lock);
861         return value;
862 fail0:
863         value = -EINVAL;
864         goto fail;
865 fail1:
866         value = -EFAULT;
867         goto fail;
868 }
869
870 static int
871 ep_open (struct inode *inode, struct file *fd)
872 {
873         struct ep_data          *data = inode->i_private;
874         int                     value = -EBUSY;
875
876         if (down_interruptible (&data->lock) != 0)
877                 return -EINTR;
878         spin_lock_irq (&data->dev->lock);
879         if (data->dev->state == STATE_DEV_UNBOUND)
880                 value = -ENOENT;
881         else if (data->state == STATE_EP_DISABLED) {
882                 value = 0;
883                 data->state = STATE_EP_READY;
884                 get_ep (data);
885                 fd->private_data = data;
886                 VDEBUG (data->dev, "%s ready\n", data->name);
887         } else
888                 DBG (data->dev, "%s state %d\n",
889                         data->name, data->state);
890         spin_unlock_irq (&data->dev->lock);
891         up (&data->lock);
892         return value;
893 }
894
895 /* used before endpoint configuration */
896 static const struct file_operations ep_config_operations = {
897         .owner =        THIS_MODULE,
898         .llseek =       no_llseek,
899
900         .open =         ep_open,
901         .write =        ep_config,
902         .release =      ep_release,
903 };
904
905 /*----------------------------------------------------------------------*/
906
907 /* EP0 IMPLEMENTATION can be partly in userspace.
908  *
909  * Drivers that use this facility receive various events, including
910  * control requests the kernel doesn't handle.  Drivers that don't
911  * use this facility may be too simple-minded for real applications.
912  */
913
914 static inline void ep0_readable (struct dev_data *dev)
915 {
916         wake_up (&dev->wait);
917         kill_fasync (&dev->fasync, SIGIO, POLL_IN);
918 }
919
920 static void clean_req (struct usb_ep *ep, struct usb_request *req)
921 {
922         struct dev_data         *dev = ep->driver_data;
923
924         if (req->buf != dev->rbuf) {
925                 kfree(req->buf);
926                 req->buf = dev->rbuf;
927                 req->dma = DMA_ADDR_INVALID;
928         }
929         req->complete = epio_complete;
930         dev->setup_out_ready = 0;
931 }
932
933 static void ep0_complete (struct usb_ep *ep, struct usb_request *req)
934 {
935         struct dev_data         *dev = ep->driver_data;
936         unsigned long           flags;
937         int                     free = 1;
938
939         /* for control OUT, data must still get to userspace */
940         spin_lock_irqsave(&dev->lock, flags);
941         if (!dev->setup_in) {
942                 dev->setup_out_error = (req->status != 0);
943                 if (!dev->setup_out_error)
944                         free = 0;
945                 dev->setup_out_ready = 1;
946                 ep0_readable (dev);
947         }
948
949         /* clean up as appropriate */
950         if (free && req->buf != &dev->rbuf)
951                 clean_req (ep, req);
952         req->complete = epio_complete;
953         spin_unlock_irqrestore(&dev->lock, flags);
954 }
955
956 static int setup_req (struct usb_ep *ep, struct usb_request *req, u16 len)
957 {
958         struct dev_data *dev = ep->driver_data;
959
960         if (dev->setup_out_ready) {
961                 DBG (dev, "ep0 request busy!\n");
962                 return -EBUSY;
963         }
964         if (len > sizeof (dev->rbuf))
965                 req->buf = kmalloc(len, GFP_ATOMIC);
966         if (req->buf == NULL) {
967                 req->buf = dev->rbuf;
968                 return -ENOMEM;
969         }
970         req->complete = ep0_complete;
971         req->length = len;
972         req->zero = 0;
973         return 0;
974 }
975
976 static ssize_t
977 ep0_read (struct file *fd, char __user *buf, size_t len, loff_t *ptr)
978 {
979         struct dev_data                 *dev = fd->private_data;
980         ssize_t                         retval;
981         enum ep0_state                  state;
982
983         spin_lock_irq (&dev->lock);
984
985         /* report fd mode change before acting on it */
986         if (dev->setup_abort) {
987                 dev->setup_abort = 0;
988                 retval = -EIDRM;
989                 goto done;
990         }
991
992         /* control DATA stage */
993         if ((state = dev->state) == STATE_DEV_SETUP) {
994
995                 if (dev->setup_in) {            /* stall IN */
996                         VDEBUG(dev, "ep0in stall\n");
997                         (void) usb_ep_set_halt (dev->gadget->ep0);
998                         retval = -EL2HLT;
999                         dev->state = STATE_DEV_CONNECTED;
1000
1001                 } else if (len == 0) {          /* ack SET_CONFIGURATION etc */
1002                         struct usb_ep           *ep = dev->gadget->ep0;
1003                         struct usb_request      *req = dev->req;
1004
1005                         if ((retval = setup_req (ep, req, 0)) == 0)
1006                                 retval = usb_ep_queue (ep, req, GFP_ATOMIC);
1007                         dev->state = STATE_DEV_CONNECTED;
1008
1009                         /* assume that was SET_CONFIGURATION */
1010                         if (dev->current_config) {
1011                                 unsigned power;
1012
1013                                 if (gadget_is_dualspeed(dev->gadget)
1014                                                 && (dev->gadget->speed
1015                                                         == USB_SPEED_HIGH))
1016                                         power = dev->hs_config->bMaxPower;
1017                                 else
1018                                         power = dev->config->bMaxPower;
1019                                 usb_gadget_vbus_draw(dev->gadget, 2 * power);
1020                         }
1021
1022                 } else {                        /* collect OUT data */
1023                         if ((fd->f_flags & O_NONBLOCK) != 0
1024                                         && !dev->setup_out_ready) {
1025                                 retval = -EAGAIN;
1026                                 goto done;
1027                         }
1028                         spin_unlock_irq (&dev->lock);
1029                         retval = wait_event_interruptible (dev->wait,
1030                                         dev->setup_out_ready != 0);
1031
1032                         /* FIXME state could change from under us */
1033                         spin_lock_irq (&dev->lock);
1034                         if (retval)
1035                                 goto done;
1036
1037                         if (dev->state != STATE_DEV_SETUP) {
1038                                 retval = -ECANCELED;
1039                                 goto done;
1040                         }
1041                         dev->state = STATE_DEV_CONNECTED;
1042
1043                         if (dev->setup_out_error)
1044                                 retval = -EIO;
1045                         else {
1046                                 len = min (len, (size_t)dev->req->actual);
1047 // FIXME don't call this with the spinlock held ...
1048                                 if (copy_to_user (buf, dev->req->buf, len))
1049                                         retval = -EFAULT;
1050                                 clean_req (dev->gadget->ep0, dev->req);
1051                                 /* NOTE userspace can't yet choose to stall */
1052                         }
1053                 }
1054                 goto done;
1055         }
1056
1057         /* else normal: return event data */
1058         if (len < sizeof dev->event [0]) {
1059                 retval = -EINVAL;
1060                 goto done;
1061         }
1062         len -= len % sizeof (struct usb_gadgetfs_event);
1063         dev->usermode_setup = 1;
1064
1065 scan:
1066         /* return queued events right away */
1067         if (dev->ev_next != 0) {
1068                 unsigned                i, n;
1069
1070                 n = len / sizeof (struct usb_gadgetfs_event);
1071                 if (dev->ev_next < n)
1072                         n = dev->ev_next;
1073
1074                 /* ep0 i/o has special semantics during STATE_DEV_SETUP */
1075                 for (i = 0; i < n; i++) {
1076                         if (dev->event [i].type == GADGETFS_SETUP) {
1077                                 dev->state = STATE_DEV_SETUP;
1078                                 n = i + 1;
1079                                 break;
1080                         }
1081                 }
1082                 spin_unlock_irq (&dev->lock);
1083                 len = n * sizeof (struct usb_gadgetfs_event);
1084                 if (copy_to_user (buf, &dev->event, len))
1085                         retval = -EFAULT;
1086                 else
1087                         retval = len;
1088                 if (len > 0) {
1089                         /* NOTE this doesn't guard against broken drivers;
1090                          * concurrent ep0 readers may lose events.
1091                          */
1092                         spin_lock_irq (&dev->lock);
1093                         if (dev->ev_next > n) {
1094                                 memmove(&dev->event[0], &dev->event[n],
1095                                         sizeof (struct usb_gadgetfs_event)
1096                                                 * (dev->ev_next - n));
1097                         }
1098                         dev->ev_next -= n;
1099                         spin_unlock_irq (&dev->lock);
1100                 }
1101                 return retval;
1102         }
1103         if (fd->f_flags & O_NONBLOCK) {
1104                 retval = -EAGAIN;
1105                 goto done;
1106         }
1107
1108         switch (state) {
1109         default:
1110                 DBG (dev, "fail %s, state %d\n", __func__, state);
1111                 retval = -ESRCH;
1112                 break;
1113         case STATE_DEV_UNCONNECTED:
1114         case STATE_DEV_CONNECTED:
1115                 spin_unlock_irq (&dev->lock);
1116                 DBG (dev, "%s wait\n", __func__);
1117
1118                 /* wait for events */
1119                 retval = wait_event_interruptible (dev->wait,
1120                                 dev->ev_next != 0);
1121                 if (retval < 0)
1122                         return retval;
1123                 spin_lock_irq (&dev->lock);
1124                 goto scan;
1125         }
1126
1127 done:
1128         spin_unlock_irq (&dev->lock);
1129         return retval;
1130 }
1131
1132 static struct usb_gadgetfs_event *
1133 next_event (struct dev_data *dev, enum usb_gadgetfs_event_type type)
1134 {
1135         struct usb_gadgetfs_event       *event;
1136         unsigned                        i;
1137
1138         switch (type) {
1139         /* these events purge the queue */
1140         case GADGETFS_DISCONNECT:
1141                 if (dev->state == STATE_DEV_SETUP)
1142                         dev->setup_abort = 1;
1143                 // FALL THROUGH
1144         case GADGETFS_CONNECT:
1145                 dev->ev_next = 0;
1146                 break;
1147         case GADGETFS_SETUP:            /* previous request timed out */
1148         case GADGETFS_SUSPEND:          /* same effect */
1149                 /* these events can't be repeated */
1150                 for (i = 0; i != dev->ev_next; i++) {
1151                         if (dev->event [i].type != type)
1152                                 continue;
1153                         DBG(dev, "discard old event[%d] %d\n", i, type);
1154                         dev->ev_next--;
1155                         if (i == dev->ev_next)
1156                                 break;
1157                         /* indices start at zero, for simplicity */
1158                         memmove (&dev->event [i], &dev->event [i + 1],
1159                                 sizeof (struct usb_gadgetfs_event)
1160                                         * (dev->ev_next - i));
1161                 }
1162                 break;
1163         default:
1164                 BUG ();
1165         }
1166         VDEBUG(dev, "event[%d] = %d\n", dev->ev_next, type);
1167         event = &dev->event [dev->ev_next++];
1168         BUG_ON (dev->ev_next > N_EVENT);
1169         memset (event, 0, sizeof *event);
1170         event->type = type;
1171         return event;
1172 }
1173
1174 static ssize_t
1175 ep0_write (struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
1176 {
1177         struct dev_data         *dev = fd->private_data;
1178         ssize_t                 retval = -ESRCH;
1179
1180         spin_lock_irq (&dev->lock);
1181
1182         /* report fd mode change before acting on it */
1183         if (dev->setup_abort) {
1184                 dev->setup_abort = 0;
1185                 retval = -EIDRM;
1186
1187         /* data and/or status stage for control request */
1188         } else if (dev->state == STATE_DEV_SETUP) {
1189
1190                 /* IN DATA+STATUS caller makes len <= wLength */
1191                 if (dev->setup_in) {
1192                         retval = setup_req (dev->gadget->ep0, dev->req, len);
1193                         if (retval == 0) {
1194                                 dev->state = STATE_DEV_CONNECTED;
1195                                 spin_unlock_irq (&dev->lock);
1196                                 if (copy_from_user (dev->req->buf, buf, len))
1197                                         retval = -EFAULT;
1198                                 else {
1199                                         if (len < dev->setup_wLength)
1200                                                 dev->req->zero = 1;
1201                                         retval = usb_ep_queue (
1202                                                 dev->gadget->ep0, dev->req,
1203                                                 GFP_KERNEL);
1204                                 }
1205                                 if (retval < 0) {
1206                                         spin_lock_irq (&dev->lock);
1207                                         clean_req (dev->gadget->ep0, dev->req);
1208                                         spin_unlock_irq (&dev->lock);
1209                                 } else
1210                                         retval = len;
1211
1212                                 return retval;
1213                         }
1214
1215                 /* can stall some OUT transfers */
1216                 } else if (dev->setup_can_stall) {
1217                         VDEBUG(dev, "ep0out stall\n");
1218                         (void) usb_ep_set_halt (dev->gadget->ep0);
1219                         retval = -EL2HLT;
1220                         dev->state = STATE_DEV_CONNECTED;
1221                 } else {
1222                         DBG(dev, "bogus ep0out stall!\n");
1223                 }
1224         } else
1225                 DBG (dev, "fail %s, state %d\n", __func__, dev->state);
1226
1227         spin_unlock_irq (&dev->lock);
1228         return retval;
1229 }
1230
1231 static int
1232 ep0_fasync (int f, struct file *fd, int on)
1233 {
1234         struct dev_data         *dev = fd->private_data;
1235         // caller must F_SETOWN before signal delivery happens
1236         VDEBUG (dev, "%s %s\n", __func__, on ? "on" : "off");
1237         return fasync_helper (f, fd, on, &dev->fasync);
1238 }
1239
1240 static struct usb_gadget_driver gadgetfs_driver;
1241
1242 static int
1243 dev_release (struct inode *inode, struct file *fd)
1244 {
1245         struct dev_data         *dev = fd->private_data;
1246
1247         /* closing ep0 === shutdown all */
1248
1249         usb_gadget_unregister_driver (&gadgetfs_driver);
1250
1251         /* at this point "good" hardware has disconnected the
1252          * device from USB; the host won't see it any more.
1253          * alternatively, all host requests will time out.
1254          */
1255
1256         fasync_helper (-1, fd, 0, &dev->fasync);
1257         kfree (dev->buf);
1258         dev->buf = NULL;
1259         put_dev (dev);
1260
1261         /* other endpoints were all decoupled from this device */
1262         spin_lock_irq(&dev->lock);
1263         dev->state = STATE_DEV_DISABLED;
1264         spin_unlock_irq(&dev->lock);
1265         return 0;
1266 }
1267
1268 static unsigned int
1269 ep0_poll (struct file *fd, poll_table *wait)
1270 {
1271        struct dev_data         *dev = fd->private_data;
1272        int                     mask = 0;
1273
1274        poll_wait(fd, &dev->wait, wait);
1275
1276        spin_lock_irq (&dev->lock);
1277
1278        /* report fd mode change before acting on it */
1279        if (dev->setup_abort) {
1280                dev->setup_abort = 0;
1281                mask = POLLHUP;
1282                goto out;
1283        }
1284
1285        if (dev->state == STATE_DEV_SETUP) {
1286                if (dev->setup_in || dev->setup_can_stall)
1287                        mask = POLLOUT;
1288        } else {
1289                if (dev->ev_next != 0)
1290                        mask = POLLIN;
1291        }
1292 out:
1293        spin_unlock_irq(&dev->lock);
1294        return mask;
1295 }
1296
1297 static int dev_ioctl (struct inode *inode, struct file *fd,
1298                 unsigned code, unsigned long value)
1299 {
1300         struct dev_data         *dev = fd->private_data;
1301         struct usb_gadget       *gadget = dev->gadget;
1302
1303         if (gadget->ops->ioctl)
1304                 return gadget->ops->ioctl (gadget, code, value);
1305         return -ENOTTY;
1306 }
1307
1308 /* used after device configuration */
1309 static const struct file_operations ep0_io_operations = {
1310         .owner =        THIS_MODULE,
1311         .llseek =       no_llseek,
1312
1313         .read =         ep0_read,
1314         .write =        ep0_write,
1315         .fasync =       ep0_fasync,
1316         .poll =         ep0_poll,
1317         .ioctl =        dev_ioctl,
1318         .release =      dev_release,
1319 };
1320
1321 /*----------------------------------------------------------------------*/
1322
1323 /* The in-kernel gadget driver handles most ep0 issues, in particular
1324  * enumerating the single configuration (as provided from user space).
1325  *
1326  * Unrecognized ep0 requests may be handled in user space.
1327  */
1328
1329 #ifdef  CONFIG_USB_GADGET_DUALSPEED
1330 static void make_qualifier (struct dev_data *dev)
1331 {
1332         struct usb_qualifier_descriptor         qual;
1333         struct usb_device_descriptor            *desc;
1334
1335         qual.bLength = sizeof qual;
1336         qual.bDescriptorType = USB_DT_DEVICE_QUALIFIER;
1337         qual.bcdUSB = __constant_cpu_to_le16 (0x0200);
1338
1339         desc = dev->dev;
1340         qual.bDeviceClass = desc->bDeviceClass;
1341         qual.bDeviceSubClass = desc->bDeviceSubClass;
1342         qual.bDeviceProtocol = desc->bDeviceProtocol;
1343
1344         /* assumes ep0 uses the same value for both speeds ... */
1345         qual.bMaxPacketSize0 = desc->bMaxPacketSize0;
1346
1347         qual.bNumConfigurations = 1;
1348         qual.bRESERVED = 0;
1349
1350         memcpy (dev->rbuf, &qual, sizeof qual);
1351 }
1352 #endif
1353
1354 static int
1355 config_buf (struct dev_data *dev, u8 type, unsigned index)
1356 {
1357         int             len;
1358         int             hs = 0;
1359
1360         /* only one configuration */
1361         if (index > 0)
1362                 return -EINVAL;
1363
1364         if (gadget_is_dualspeed(dev->gadget)) {
1365                 hs = (dev->gadget->speed == USB_SPEED_HIGH);
1366                 if (type == USB_DT_OTHER_SPEED_CONFIG)
1367                         hs = !hs;
1368         }
1369         if (hs) {
1370                 dev->req->buf = dev->hs_config;
1371                 len = le16_to_cpu(dev->hs_config->wTotalLength);
1372         } else {
1373                 dev->req->buf = dev->config;
1374                 len = le16_to_cpu(dev->config->wTotalLength);
1375         }
1376         ((u8 *)dev->req->buf) [1] = type;
1377         return len;
1378 }
1379
1380 static int
1381 gadgetfs_setup (struct usb_gadget *gadget, const struct usb_ctrlrequest *ctrl)
1382 {
1383         struct dev_data                 *dev = get_gadget_data (gadget);
1384         struct usb_request              *req = dev->req;
1385         int                             value = -EOPNOTSUPP;
1386         struct usb_gadgetfs_event       *event;
1387         u16                             w_value = le16_to_cpu(ctrl->wValue);
1388         u16                             w_length = le16_to_cpu(ctrl->wLength);
1389
1390         spin_lock (&dev->lock);
1391         dev->setup_abort = 0;
1392         if (dev->state == STATE_DEV_UNCONNECTED) {
1393                 if (gadget_is_dualspeed(gadget)
1394                                 && gadget->speed == USB_SPEED_HIGH
1395                                 && dev->hs_config == NULL) {
1396                         spin_unlock(&dev->lock);
1397                         ERROR (dev, "no high speed config??\n");
1398                         return -EINVAL;
1399                 }
1400
1401                 dev->state = STATE_DEV_CONNECTED;
1402                 dev->dev->bMaxPacketSize0 = gadget->ep0->maxpacket;
1403
1404                 INFO (dev, "connected\n");
1405                 event = next_event (dev, GADGETFS_CONNECT);
1406                 event->u.speed = gadget->speed;
1407                 ep0_readable (dev);
1408
1409         /* host may have given up waiting for response.  we can miss control
1410          * requests handled lower down (device/endpoint status and features);
1411          * then ep0_{read,write} will report the wrong status. controller
1412          * driver will have aborted pending i/o.
1413          */
1414         } else if (dev->state == STATE_DEV_SETUP)
1415                 dev->setup_abort = 1;
1416
1417         req->buf = dev->rbuf;
1418         req->dma = DMA_ADDR_INVALID;
1419         req->context = NULL;
1420         value = -EOPNOTSUPP;
1421         switch (ctrl->bRequest) {
1422
1423         case USB_REQ_GET_DESCRIPTOR:
1424                 if (ctrl->bRequestType != USB_DIR_IN)
1425                         goto unrecognized;
1426                 switch (w_value >> 8) {
1427
1428                 case USB_DT_DEVICE:
1429                         value = min (w_length, (u16) sizeof *dev->dev);
1430                         req->buf = dev->dev;
1431                         break;
1432 #ifdef  CONFIG_USB_GADGET_DUALSPEED
1433                 case USB_DT_DEVICE_QUALIFIER:
1434                         if (!dev->hs_config)
1435                                 break;
1436                         value = min (w_length, (u16)
1437                                 sizeof (struct usb_qualifier_descriptor));
1438                         make_qualifier (dev);
1439                         break;
1440                 case USB_DT_OTHER_SPEED_CONFIG:
1441                         // FALLTHROUGH
1442 #endif
1443                 case USB_DT_CONFIG:
1444                         value = config_buf (dev,
1445                                         w_value >> 8,
1446                                         w_value & 0xff);
1447                         if (value >= 0)
1448                                 value = min (w_length, (u16) value);
1449                         break;
1450                 case USB_DT_STRING:
1451                         goto unrecognized;
1452
1453                 default:                // all others are errors
1454                         break;
1455                 }
1456                 break;
1457
1458         /* currently one config, two speeds */
1459         case USB_REQ_SET_CONFIGURATION:
1460                 if (ctrl->bRequestType != 0)
1461                         goto unrecognized;
1462                 if (0 == (u8) w_value) {
1463                         value = 0;
1464                         dev->current_config = 0;
1465                         usb_gadget_vbus_draw(gadget, 8 /* mA */ );
1466                         // user mode expected to disable endpoints
1467                 } else {
1468                         u8      config, power;
1469
1470                         if (gadget_is_dualspeed(gadget)
1471                                         && gadget->speed == USB_SPEED_HIGH) {
1472                                 config = dev->hs_config->bConfigurationValue;
1473                                 power = dev->hs_config->bMaxPower;
1474                         } else {
1475                                 config = dev->config->bConfigurationValue;
1476                                 power = dev->config->bMaxPower;
1477                         }
1478
1479                         if (config == (u8) w_value) {
1480                                 value = 0;
1481                                 dev->current_config = config;
1482                                 usb_gadget_vbus_draw(gadget, 2 * power);
1483                         }
1484                 }
1485
1486                 /* report SET_CONFIGURATION like any other control request,
1487                  * except that usermode may not stall this.  the next
1488                  * request mustn't be allowed start until this finishes:
1489                  * endpoints and threads set up, etc.
1490                  *
1491                  * NOTE:  older PXA hardware (before PXA 255: without UDCCFR)
1492                  * has bad/racey automagic that prevents synchronizing here.
1493                  * even kernel mode drivers often miss them.
1494                  */
1495                 if (value == 0) {
1496                         INFO (dev, "configuration #%d\n", dev->current_config);
1497                         if (dev->usermode_setup) {
1498                                 dev->setup_can_stall = 0;
1499                                 goto delegate;
1500                         }
1501                 }
1502                 break;
1503
1504 #ifndef CONFIG_USB_GADGET_PXA25X
1505         /* PXA automagically handles this request too */
1506         case USB_REQ_GET_CONFIGURATION:
1507                 if (ctrl->bRequestType != 0x80)
1508                         goto unrecognized;
1509                 *(u8 *)req->buf = dev->current_config;
1510                 value = min (w_length, (u16) 1);
1511                 break;
1512 #endif
1513
1514         default:
1515 unrecognized:
1516                 VDEBUG (dev, "%s req%02x.%02x v%04x i%04x l%d\n",
1517                         dev->usermode_setup ? "delegate" : "fail",
1518                         ctrl->bRequestType, ctrl->bRequest,
1519                         w_value, le16_to_cpu(ctrl->wIndex), w_length);
1520
1521                 /* if there's an ep0 reader, don't stall */
1522                 if (dev->usermode_setup) {
1523                         dev->setup_can_stall = 1;
1524 delegate:
1525                         dev->setup_in = (ctrl->bRequestType & USB_DIR_IN)
1526                                                 ? 1 : 0;
1527                         dev->setup_wLength = w_length;
1528                         dev->setup_out_ready = 0;
1529                         dev->setup_out_error = 0;
1530                         value = 0;
1531
1532                         /* read DATA stage for OUT right away */
1533                         if (unlikely (!dev->setup_in && w_length)) {
1534                                 value = setup_req (gadget->ep0, dev->req,
1535                                                         w_length);
1536                                 if (value < 0)
1537                                         break;
1538                                 value = usb_ep_queue (gadget->ep0, dev->req,
1539                                                         GFP_ATOMIC);
1540                                 if (value < 0) {
1541                                         clean_req (gadget->ep0, dev->req);
1542                                         break;
1543                                 }
1544
1545                                 /* we can't currently stall these */
1546                                 dev->setup_can_stall = 0;
1547                         }
1548
1549                         /* state changes when reader collects event */
1550                         event = next_event (dev, GADGETFS_SETUP);
1551                         event->u.setup = *ctrl;
1552                         ep0_readable (dev);
1553                         spin_unlock (&dev->lock);
1554                         return 0;
1555                 }
1556         }
1557
1558         /* proceed with data transfer and status phases? */
1559         if (value >= 0 && dev->state != STATE_DEV_SETUP) {
1560                 req->length = value;
1561                 req->zero = value < w_length;
1562                 value = usb_ep_queue (gadget->ep0, req, GFP_ATOMIC);
1563                 if (value < 0) {
1564                         DBG (dev, "ep_queue --> %d\n", value);
1565                         req->status = 0;
1566                 }
1567         }
1568
1569         /* device stalls when value < 0 */
1570         spin_unlock (&dev->lock);
1571         return value;
1572 }
1573
1574 static void destroy_ep_files (struct dev_data *dev)
1575 {
1576         struct list_head        *entry, *tmp;
1577
1578         DBG (dev, "%s %d\n", __func__, dev->state);
1579
1580         /* dev->state must prevent interference */
1581 restart:
1582         spin_lock_irq (&dev->lock);
1583         list_for_each_safe (entry, tmp, &dev->epfiles) {
1584                 struct ep_data  *ep;
1585                 struct inode    *parent;
1586                 struct dentry   *dentry;
1587
1588                 /* break link to FS */
1589                 ep = list_entry (entry, struct ep_data, epfiles);
1590                 list_del_init (&ep->epfiles);
1591                 dentry = ep->dentry;
1592                 ep->dentry = NULL;
1593                 parent = dentry->d_parent->d_inode;
1594
1595                 /* break link to controller */
1596                 if (ep->state == STATE_EP_ENABLED)
1597                         (void) usb_ep_disable (ep->ep);
1598                 ep->state = STATE_EP_UNBOUND;
1599                 usb_ep_free_request (ep->ep, ep->req);
1600                 ep->ep = NULL;
1601                 wake_up (&ep->wait);
1602                 put_ep (ep);
1603
1604                 spin_unlock_irq (&dev->lock);
1605
1606                 /* break link to dcache */
1607                 mutex_lock (&parent->i_mutex);
1608                 d_delete (dentry);
1609                 dput (dentry);
1610                 mutex_unlock (&parent->i_mutex);
1611
1612                 /* fds may still be open */
1613                 goto restart;
1614         }
1615         spin_unlock_irq (&dev->lock);
1616 }
1617
1618
1619 static struct inode *
1620 gadgetfs_create_file (struct super_block *sb, char const *name,
1621                 void *data, const struct file_operations *fops,
1622                 struct dentry **dentry_p);
1623
1624 static int activate_ep_files (struct dev_data *dev)
1625 {
1626         struct usb_ep   *ep;
1627         struct ep_data  *data;
1628
1629         gadget_for_each_ep (ep, dev->gadget) {
1630
1631                 data = kzalloc(sizeof(*data), GFP_KERNEL);
1632                 if (!data)
1633                         goto enomem0;
1634                 data->state = STATE_EP_DISABLED;
1635                 init_MUTEX (&data->lock);
1636                 init_waitqueue_head (&data->wait);
1637
1638                 strncpy (data->name, ep->name, sizeof (data->name) - 1);
1639                 atomic_set (&data->count, 1);
1640                 data->dev = dev;
1641                 get_dev (dev);
1642
1643                 data->ep = ep;
1644                 ep->driver_data = data;
1645
1646                 data->req = usb_ep_alloc_request (ep, GFP_KERNEL);
1647                 if (!data->req)
1648                         goto enomem1;
1649
1650                 data->inode = gadgetfs_create_file (dev->sb, data->name,
1651                                 data, &ep_config_operations,
1652                                 &data->dentry);
1653                 if (!data->inode)
1654                         goto enomem2;
1655                 list_add_tail (&data->epfiles, &dev->epfiles);
1656         }
1657         return 0;
1658
1659 enomem2:
1660         usb_ep_free_request (ep, data->req);
1661 enomem1:
1662         put_dev (dev);
1663         kfree (data);
1664 enomem0:
1665         DBG (dev, "%s enomem\n", __func__);
1666         destroy_ep_files (dev);
1667         return -ENOMEM;
1668 }
1669
1670 static void
1671 gadgetfs_unbind (struct usb_gadget *gadget)
1672 {
1673         struct dev_data         *dev = get_gadget_data (gadget);
1674
1675         DBG (dev, "%s\n", __func__);
1676
1677         spin_lock_irq (&dev->lock);
1678         dev->state = STATE_DEV_UNBOUND;
1679         spin_unlock_irq (&dev->lock);
1680
1681         destroy_ep_files (dev);
1682         gadget->ep0->driver_data = NULL;
1683         set_gadget_data (gadget, NULL);
1684
1685         /* we've already been disconnected ... no i/o is active */
1686         if (dev->req)
1687                 usb_ep_free_request (gadget->ep0, dev->req);
1688         DBG (dev, "%s done\n", __func__);
1689         put_dev (dev);
1690 }
1691
1692 static struct dev_data          *the_device;
1693
1694 static int
1695 gadgetfs_bind (struct usb_gadget *gadget)
1696 {
1697         struct dev_data         *dev = the_device;
1698
1699         if (!dev)
1700                 return -ESRCH;
1701         if (0 != strcmp (CHIP, gadget->name)) {
1702                 pr_err("%s expected %s controller not %s\n",
1703                         shortname, CHIP, gadget->name);
1704                 return -ENODEV;
1705         }
1706
1707         set_gadget_data (gadget, dev);
1708         dev->gadget = gadget;
1709         gadget->ep0->driver_data = dev;
1710         dev->dev->bMaxPacketSize0 = gadget->ep0->maxpacket;
1711
1712         /* preallocate control response and buffer */
1713         dev->req = usb_ep_alloc_request (gadget->ep0, GFP_KERNEL);
1714         if (!dev->req)
1715                 goto enomem;
1716         dev->req->context = NULL;
1717         dev->req->complete = epio_complete;
1718
1719         if (activate_ep_files (dev) < 0)
1720                 goto enomem;
1721
1722         INFO (dev, "bound to %s driver\n", gadget->name);
1723         spin_lock_irq(&dev->lock);
1724         dev->state = STATE_DEV_UNCONNECTED;
1725         spin_unlock_irq(&dev->lock);
1726         get_dev (dev);
1727         return 0;
1728
1729 enomem:
1730         gadgetfs_unbind (gadget);
1731         return -ENOMEM;
1732 }
1733
1734 static void
1735 gadgetfs_disconnect (struct usb_gadget *gadget)
1736 {
1737         struct dev_data         *dev = get_gadget_data (gadget);
1738
1739         spin_lock (&dev->lock);
1740         if (dev->state == STATE_DEV_UNCONNECTED)
1741                 goto exit;
1742         dev->state = STATE_DEV_UNCONNECTED;
1743
1744         INFO (dev, "disconnected\n");
1745         next_event (dev, GADGETFS_DISCONNECT);
1746         ep0_readable (dev);
1747 exit:
1748         spin_unlock (&dev->lock);
1749 }
1750
1751 static void
1752 gadgetfs_suspend (struct usb_gadget *gadget)
1753 {
1754         struct dev_data         *dev = get_gadget_data (gadget);
1755
1756         INFO (dev, "suspended from state %d\n", dev->state);
1757         spin_lock (&dev->lock);
1758         switch (dev->state) {
1759         case STATE_DEV_SETUP:           // VERY odd... host died??
1760         case STATE_DEV_CONNECTED:
1761         case STATE_DEV_UNCONNECTED:
1762                 next_event (dev, GADGETFS_SUSPEND);
1763                 ep0_readable (dev);
1764                 /* FALLTHROUGH */
1765         default:
1766                 break;
1767         }
1768         spin_unlock (&dev->lock);
1769 }
1770
1771 static struct usb_gadget_driver gadgetfs_driver = {
1772 #ifdef  CONFIG_USB_GADGET_DUALSPEED
1773         .speed          = USB_SPEED_HIGH,
1774 #else
1775         .speed          = USB_SPEED_FULL,
1776 #endif
1777         .function       = (char *) driver_desc,
1778         .bind           = gadgetfs_bind,
1779         .unbind         = gadgetfs_unbind,
1780         .setup          = gadgetfs_setup,
1781         .disconnect     = gadgetfs_disconnect,
1782         .suspend        = gadgetfs_suspend,
1783
1784         .driver = {
1785                 .name           = (char *) shortname,
1786         },
1787 };
1788
1789 /*----------------------------------------------------------------------*/
1790
1791 static void gadgetfs_nop(struct usb_gadget *arg) { }
1792
1793 static int gadgetfs_probe (struct usb_gadget *gadget)
1794 {
1795         CHIP = gadget->name;
1796         return -EISNAM;
1797 }
1798
1799 static struct usb_gadget_driver probe_driver = {
1800         .speed          = USB_SPEED_HIGH,
1801         .bind           = gadgetfs_probe,
1802         .unbind         = gadgetfs_nop,
1803         .setup          = (void *)gadgetfs_nop,
1804         .disconnect     = gadgetfs_nop,
1805         .driver = {
1806                 .name           = "nop",
1807         },
1808 };
1809
1810
1811 /* DEVICE INITIALIZATION
1812  *
1813  *     fd = open ("/dev/gadget/$CHIP", O_RDWR)
1814  *     status = write (fd, descriptors, sizeof descriptors)
1815  *
1816  * That write establishes the device configuration, so the kernel can
1817  * bind to the controller ... guaranteeing it can handle enumeration
1818  * at all necessary speeds.  Descriptor order is:
1819  *
1820  * . message tag (u32, host order) ... for now, must be zero; it
1821  *      would change to support features like multi-config devices
1822  * . full/low speed config ... all wTotalLength bytes (with interface,
1823  *      class, altsetting, endpoint, and other descriptors)
1824  * . high speed config ... all descriptors, for high speed operation;
1825  *      this one's optional except for high-speed hardware
1826  * . device descriptor
1827  *
1828  * Endpoints are not yet enabled. Drivers must wait until device
1829  * configuration and interface altsetting changes create
1830  * the need to configure (or unconfigure) them.
1831  *
1832  * After initialization, the device stays active for as long as that
1833  * $CHIP file is open.  Events must then be read from that descriptor,
1834  * such as configuration notifications.
1835  */
1836
1837 static int is_valid_config (struct usb_config_descriptor *config)
1838 {
1839         return config->bDescriptorType == USB_DT_CONFIG
1840                 && config->bLength == USB_DT_CONFIG_SIZE
1841                 && config->bConfigurationValue != 0
1842                 && (config->bmAttributes & USB_CONFIG_ATT_ONE) != 0
1843                 && (config->bmAttributes & USB_CONFIG_ATT_WAKEUP) == 0;
1844         /* FIXME if gadget->is_otg, _must_ include an otg descriptor */
1845         /* FIXME check lengths: walk to end */
1846 }
1847
1848 static ssize_t
1849 dev_config (struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
1850 {
1851         struct dev_data         *dev = fd->private_data;
1852         ssize_t                 value = len, length = len;
1853         unsigned                total;
1854         u32                     tag;
1855         char                    *kbuf;
1856
1857         if (len < (USB_DT_CONFIG_SIZE + USB_DT_DEVICE_SIZE + 4))
1858                 return -EINVAL;
1859
1860         /* we might need to change message format someday */
1861         if (copy_from_user (&tag, buf, 4))
1862                 return -EFAULT;
1863         if (tag != 0)
1864                 return -EINVAL;
1865         buf += 4;
1866         length -= 4;
1867
1868         kbuf = kmalloc (length, GFP_KERNEL);
1869         if (!kbuf)
1870                 return -ENOMEM;
1871         if (copy_from_user (kbuf, buf, length)) {
1872                 kfree (kbuf);
1873                 return -EFAULT;
1874         }
1875
1876         spin_lock_irq (&dev->lock);
1877         value = -EINVAL;
1878         if (dev->buf)
1879                 goto fail;
1880         dev->buf = kbuf;
1881
1882         /* full or low speed config */
1883         dev->config = (void *) kbuf;
1884         total = le16_to_cpu(dev->config->wTotalLength);
1885         if (!is_valid_config (dev->config) || total >= length)
1886                 goto fail;
1887         kbuf += total;
1888         length -= total;
1889
1890         /* optional high speed config */
1891         if (kbuf [1] == USB_DT_CONFIG) {
1892                 dev->hs_config = (void *) kbuf;
1893                 total = le16_to_cpu(dev->hs_config->wTotalLength);
1894                 if (!is_valid_config (dev->hs_config) || total >= length)
1895                         goto fail;
1896                 kbuf += total;
1897                 length -= total;
1898         }
1899
1900         /* could support multiple configs, using another encoding! */
1901
1902         /* device descriptor (tweaked for paranoia) */
1903         if (length != USB_DT_DEVICE_SIZE)
1904                 goto fail;
1905         dev->dev = (void *)kbuf;
1906         if (dev->dev->bLength != USB_DT_DEVICE_SIZE
1907                         || dev->dev->bDescriptorType != USB_DT_DEVICE
1908                         || dev->dev->bNumConfigurations != 1)
1909                 goto fail;
1910         dev->dev->bNumConfigurations = 1;
1911         dev->dev->bcdUSB = __constant_cpu_to_le16 (0x0200);
1912
1913         /* triggers gadgetfs_bind(); then we can enumerate. */
1914         spin_unlock_irq (&dev->lock);
1915         value = usb_gadget_register_driver (&gadgetfs_driver);
1916         if (value != 0) {
1917                 kfree (dev->buf);
1918                 dev->buf = NULL;
1919         } else {
1920                 /* at this point "good" hardware has for the first time
1921                  * let the USB the host see us.  alternatively, if users
1922                  * unplug/replug that will clear all the error state.
1923                  *
1924                  * note:  everything running before here was guaranteed
1925                  * to choke driver model style diagnostics.  from here
1926                  * on, they can work ... except in cleanup paths that
1927                  * kick in after the ep0 descriptor is closed.
1928                  */
1929                 fd->f_op = &ep0_io_operations;
1930                 value = len;
1931         }
1932         return value;
1933
1934 fail:
1935         spin_unlock_irq (&dev->lock);
1936         pr_debug ("%s: %s fail %Zd, %p\n", shortname, __func__, value, dev);
1937         kfree (dev->buf);
1938         dev->buf = NULL;
1939         return value;
1940 }
1941
1942 static int
1943 dev_open (struct inode *inode, struct file *fd)
1944 {
1945         struct dev_data         *dev = inode->i_private;
1946         int                     value = -EBUSY;
1947
1948         spin_lock_irq(&dev->lock);
1949         if (dev->state == STATE_DEV_DISABLED) {
1950                 dev->ev_next = 0;
1951                 dev->state = STATE_DEV_OPENED;
1952                 fd->private_data = dev;
1953                 get_dev (dev);
1954                 value = 0;
1955         }
1956         spin_unlock_irq(&dev->lock);
1957         return value;
1958 }
1959
1960 static const struct file_operations dev_init_operations = {
1961         .owner =        THIS_MODULE,
1962         .llseek =       no_llseek,
1963
1964         .open =         dev_open,
1965         .write =        dev_config,
1966         .fasync =       ep0_fasync,
1967         .ioctl =        dev_ioctl,
1968         .release =      dev_release,
1969 };
1970
1971 /*----------------------------------------------------------------------*/
1972
1973 /* FILESYSTEM AND SUPERBLOCK OPERATIONS
1974  *
1975  * Mounting the filesystem creates a controller file, used first for
1976  * device configuration then later for event monitoring.
1977  */
1978
1979
1980 /* FIXME PAM etc could set this security policy without mount options
1981  * if epfiles inherited ownership and permissons from ep0 ...
1982  */
1983
1984 static unsigned default_uid;
1985 static unsigned default_gid;
1986 static unsigned default_perm = S_IRUSR | S_IWUSR;
1987
1988 module_param (default_uid, uint, 0644);
1989 module_param (default_gid, uint, 0644);
1990 module_param (default_perm, uint, 0644);
1991
1992
1993 static struct inode *
1994 gadgetfs_make_inode (struct super_block *sb,
1995                 void *data, const struct file_operations *fops,
1996                 int mode)
1997 {
1998         struct inode *inode = new_inode (sb);
1999
2000         if (inode) {
2001                 inode->i_mode = mode;
2002                 inode->i_uid = default_uid;
2003                 inode->i_gid = default_gid;
2004                 inode->i_blocks = 0;
2005                 inode->i_atime = inode->i_mtime = inode->i_ctime
2006                                 = CURRENT_TIME;
2007                 inode->i_private = data;
2008                 inode->i_fop = fops;
2009         }
2010         return inode;
2011 }
2012
2013 /* creates in fs root directory, so non-renamable and non-linkable.
2014  * so inode and dentry are paired, until device reconfig.
2015  */
2016 static struct inode *
2017 gadgetfs_create_file (struct super_block *sb, char const *name,
2018                 void *data, const struct file_operations *fops,
2019                 struct dentry **dentry_p)
2020 {
2021         struct dentry   *dentry;
2022         struct inode    *inode;
2023
2024         dentry = d_alloc_name(sb->s_root, name);
2025         if (!dentry)
2026                 return NULL;
2027
2028         inode = gadgetfs_make_inode (sb, data, fops,
2029                         S_IFREG | (default_perm & S_IRWXUGO));
2030         if (!inode) {
2031                 dput(dentry);
2032                 return NULL;
2033         }
2034         d_add (dentry, inode);
2035         *dentry_p = dentry;
2036         return inode;
2037 }
2038
2039 static struct super_operations gadget_fs_operations = {
2040         .statfs =       simple_statfs,
2041         .drop_inode =   generic_delete_inode,
2042 };
2043
2044 static int
2045 gadgetfs_fill_super (struct super_block *sb, void *opts, int silent)
2046 {
2047         struct inode    *inode;
2048         struct dentry   *d;
2049         struct dev_data *dev;
2050
2051         if (the_device)
2052                 return -ESRCH;
2053
2054         /* fake probe to determine $CHIP */
2055         (void) usb_gadget_register_driver (&probe_driver);
2056         if (!CHIP)
2057                 return -ENODEV;
2058
2059         /* superblock */
2060         sb->s_blocksize = PAGE_CACHE_SIZE;
2061         sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
2062         sb->s_magic = GADGETFS_MAGIC;
2063         sb->s_op = &gadget_fs_operations;
2064         sb->s_time_gran = 1;
2065
2066         /* root inode */
2067         inode = gadgetfs_make_inode (sb,
2068                         NULL, &simple_dir_operations,
2069                         S_IFDIR | S_IRUGO | S_IXUGO);
2070         if (!inode)
2071                 goto enomem0;
2072         inode->i_op = &simple_dir_inode_operations;
2073         if (!(d = d_alloc_root (inode)))
2074                 goto enomem1;
2075         sb->s_root = d;
2076
2077         /* the ep0 file is named after the controller we expect;
2078          * user mode code can use it for sanity checks, like we do.
2079          */
2080         dev = dev_new ();
2081         if (!dev)
2082                 goto enomem2;
2083
2084         dev->sb = sb;
2085         if (!gadgetfs_create_file (sb, CHIP,
2086                                 dev, &dev_init_operations,
2087                                 &dev->dentry))
2088                 goto enomem3;
2089
2090         /* other endpoint files are available after hardware setup,
2091          * from binding to a controller.
2092          */
2093         the_device = dev;
2094         return 0;
2095
2096 enomem3:
2097         put_dev (dev);
2098 enomem2:
2099         dput (d);
2100 enomem1:
2101         iput (inode);
2102 enomem0:
2103         return -ENOMEM;
2104 }
2105
2106 /* "mount -t gadgetfs path /dev/gadget" ends up here */
2107 static int
2108 gadgetfs_get_sb (struct file_system_type *t, int flags,
2109                 const char *path, void *opts, struct vfsmount *mnt)
2110 {
2111         return get_sb_single (t, flags, opts, gadgetfs_fill_super, mnt);
2112 }
2113
2114 static void
2115 gadgetfs_kill_sb (struct super_block *sb)
2116 {
2117         kill_litter_super (sb);
2118         if (the_device) {
2119                 put_dev (the_device);
2120                 the_device = NULL;
2121         }
2122 }
2123
2124 /*----------------------------------------------------------------------*/
2125
2126 static struct file_system_type gadgetfs_type = {
2127         .owner          = THIS_MODULE,
2128         .name           = shortname,
2129         .get_sb         = gadgetfs_get_sb,
2130         .kill_sb        = gadgetfs_kill_sb,
2131 };
2132
2133 /*----------------------------------------------------------------------*/
2134
2135 static int __init init (void)
2136 {
2137         int status;
2138
2139         status = register_filesystem (&gadgetfs_type);
2140         if (status == 0)
2141                 pr_info ("%s: %s, version " DRIVER_VERSION "\n",
2142                         shortname, driver_desc);
2143         return status;
2144 }
2145 module_init (init);
2146
2147 static void __exit cleanup (void)
2148 {
2149         pr_debug ("unregister %s\n", shortname);
2150         unregister_filesystem (&gadgetfs_type);
2151 }
2152 module_exit (cleanup);
2153