Merge branch 'core/xen' into x86/xen
[safe/jmp/linux-2.6] / drivers / media / video / gspca / gspca.c
1 /*
2  * Main USB camera driver
3  *
4  * V4L2 by Jean-Francois Moine <http://moinejf.free.fr>
5  *
6  * This program is free software; you can redistribute it and/or modify it
7  * under the terms of the GNU General Public License as published by the
8  * Free Software Foundation; either version 2 of the License, or (at your
9  * option) any later version.
10  *
11  * This program is distributed in the hope that it will be useful, but
12  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
13  * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
14  * for more details.
15  *
16  * You should have received a copy of the GNU General Public License
17  * along with this program; if not, write to the Free Software Foundation,
18  * Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
19  */
20
21 #define MODULE_NAME "gspca"
22
23 #include <linux/init.h>
24 #include <linux/fs.h>
25 #include <linux/vmalloc.h>
26 #include <linux/sched.h>
27 #include <linux/slab.h>
28 #include <linux/mm.h>
29 #include <linux/string.h>
30 #include <linux/pagemap.h>
31 #include <linux/io.h>
32 #include <asm/page.h>
33 #include <linux/uaccess.h>
34 #include <linux/jiffies.h>
35 #include <media/v4l2-ioctl.h>
36
37 #include "gspca.h"
38
39 /* global values */
40 #define DEF_NURBS 2             /* default number of URBs */
41
42 MODULE_AUTHOR("Jean-Francois Moine <http://moinejf.free.fr>");
43 MODULE_DESCRIPTION("GSPCA USB Camera Driver");
44 MODULE_LICENSE("GPL");
45
46 #define DRIVER_VERSION_NUMBER   KERNEL_VERSION(2, 2, 0)
47
48 static int video_nr = -1;
49
50 #ifdef GSPCA_DEBUG
51 int gspca_debug = D_ERR | D_PROBE;
52 EXPORT_SYMBOL(gspca_debug);
53
54 static void PDEBUG_MODE(char *txt, __u32 pixfmt, int w, int h)
55 {
56         if ((pixfmt >> 24) >= '0' && (pixfmt >> 24) <= 'z') {
57                 PDEBUG(D_CONF|D_STREAM, "%s %c%c%c%c %dx%d",
58                         txt,
59                         pixfmt & 0xff,
60                         (pixfmt >> 8) & 0xff,
61                         (pixfmt >> 16) & 0xff,
62                         pixfmt >> 24,
63                         w, h);
64         } else {
65                 PDEBUG(D_CONF|D_STREAM, "%s 0x%08x %dx%d",
66                         txt,
67                         pixfmt,
68                         w, h);
69         }
70 }
71 #else
72 #define PDEBUG_MODE(txt, pixfmt, w, h)
73 #endif
74
75 /* specific memory types - !! should different from V4L2_MEMORY_xxx */
76 #define GSPCA_MEMORY_NO 0       /* V4L2_MEMORY_xxx starts from 1 */
77 #define GSPCA_MEMORY_READ 7
78
79 #define BUF_ALL_FLAGS (V4L2_BUF_FLAG_QUEUED | V4L2_BUF_FLAG_DONE)
80
81 /*
82  * VMA operations.
83  */
84 static void gspca_vm_open(struct vm_area_struct *vma)
85 {
86         struct gspca_frame *frame = vma->vm_private_data;
87
88         frame->vma_use_count++;
89         frame->v4l2_buf.flags |= V4L2_BUF_FLAG_MAPPED;
90 }
91
92 static void gspca_vm_close(struct vm_area_struct *vma)
93 {
94         struct gspca_frame *frame = vma->vm_private_data;
95
96         if (--frame->vma_use_count <= 0)
97                 frame->v4l2_buf.flags &= ~V4L2_BUF_FLAG_MAPPED;
98 }
99
100 static struct vm_operations_struct gspca_vm_ops = {
101         .open           = gspca_vm_open,
102         .close          = gspca_vm_close,
103 };
104
105 /*
106  * fill a video frame from an URB and resubmit
107  */
108 static void fill_frame(struct gspca_dev *gspca_dev,
109                         struct urb *urb)
110 {
111         struct gspca_frame *frame;
112         __u8 *data;             /* address of data in the iso message */
113         int i, j, len, st;
114         cam_pkt_op pkt_scan;
115
116         if (urb->status != 0) {
117 #ifdef CONFIG_PM
118                 if (!gspca_dev->frozen)
119 #endif
120                         PDEBUG(D_ERR|D_PACK, "urb status: %d", urb->status);
121                 return;         /* disconnection ? */
122         }
123         pkt_scan = gspca_dev->sd_desc->pkt_scan;
124         for (i = 0; i < urb->number_of_packets; i++) {
125
126                 /* check the availability of the frame buffer */
127                 j = gspca_dev->fr_i;
128                 j = gspca_dev->fr_queue[j];
129                 frame = &gspca_dev->frame[j];
130                 if ((frame->v4l2_buf.flags & BUF_ALL_FLAGS)
131                                         != V4L2_BUF_FLAG_QUEUED) {
132                         gspca_dev->last_packet_type = DISCARD_PACKET;
133                         break;
134                 }
135
136                 /* check the packet status and length */
137                 len = urb->iso_frame_desc[i].actual_length;
138                 if (len == 0)
139                         continue;
140                 st = urb->iso_frame_desc[i].status;
141                 if (st) {
142                         PDEBUG(D_ERR,
143                                 "ISOC data error: [%d] len=%d, status=%d",
144                                 i, len, st);
145                         gspca_dev->last_packet_type = DISCARD_PACKET;
146                         continue;
147                 }
148
149                 /* let the packet be analyzed by the subdriver */
150                 PDEBUG(D_PACK, "packet [%d] o:%d l:%d",
151                         i, urb->iso_frame_desc[i].offset, len);
152                 data = (__u8 *) urb->transfer_buffer
153                                         + urb->iso_frame_desc[i].offset;
154                 pkt_scan(gspca_dev, frame, data, len);
155         }
156
157         /* resubmit the URB */
158         urb->status = 0;
159         st = usb_submit_urb(urb, GFP_ATOMIC);
160         if (st < 0)
161                 PDEBUG(D_ERR|D_PACK, "usb_submit_urb() ret %d", st);
162 }
163
164 /*
165  * ISOC message interrupt from the USB device
166  *
167  * Analyse each packet and call the subdriver for copy to the frame buffer.
168  */
169 static void isoc_irq(struct urb *urb
170 )
171 {
172         struct gspca_dev *gspca_dev = (struct gspca_dev *) urb->context;
173
174         PDEBUG(D_PACK, "isoc irq");
175         if (!gspca_dev->streaming)
176                 return;
177         fill_frame(gspca_dev, urb);
178 }
179
180 /*
181  * add data to the current frame
182  *
183  * This function is called by the subdrivers at interrupt level.
184  *
185  * To build a frame, these ones must add
186  *      - one FIRST_PACKET
187  *      - 0 or many INTER_PACKETs
188  *      - one LAST_PACKET
189  * DISCARD_PACKET invalidates the whole frame.
190  * On LAST_PACKET, a new frame is returned.
191  */
192 struct gspca_frame *gspca_frame_add(struct gspca_dev *gspca_dev,
193                                     int packet_type,
194                                     struct gspca_frame *frame,
195                                     const __u8 *data,
196                                     int len)
197 {
198         int i, j;
199
200         PDEBUG(D_PACK, "add t:%d l:%d", packet_type, len);
201
202         /* when start of a new frame, if the current frame buffer
203          * is not queued, discard the whole frame */
204         if (packet_type == FIRST_PACKET) {
205                 if ((frame->v4l2_buf.flags & BUF_ALL_FLAGS)
206                                                 != V4L2_BUF_FLAG_QUEUED) {
207                         gspca_dev->last_packet_type = DISCARD_PACKET;
208                         return frame;
209                 }
210                 frame->data_end = frame->data;
211                 jiffies_to_timeval(get_jiffies_64(),
212                                    &frame->v4l2_buf.timestamp);
213                 frame->v4l2_buf.sequence = ++gspca_dev->sequence;
214         } else if (gspca_dev->last_packet_type == DISCARD_PACKET) {
215                 if (packet_type == LAST_PACKET)
216                         gspca_dev->last_packet_type = packet_type;
217                 return frame;
218         }
219
220         /* append the packet to the frame buffer */
221         if (len > 0) {
222                 if (frame->data_end - frame->data + len
223                                                  > frame->v4l2_buf.length) {
224                         PDEBUG(D_ERR|D_PACK, "frame overflow %zd > %d",
225                                 frame->data_end - frame->data + len,
226                                 frame->v4l2_buf.length);
227                         packet_type = DISCARD_PACKET;
228                 } else {
229                         memcpy(frame->data_end, data, len);
230                         frame->data_end += len;
231                 }
232         }
233         gspca_dev->last_packet_type = packet_type;
234
235         /* if last packet, wake the application and advance in the queue */
236         if (packet_type == LAST_PACKET) {
237                 frame->v4l2_buf.bytesused = frame->data_end - frame->data;
238                 frame->v4l2_buf.flags &= ~V4L2_BUF_FLAG_QUEUED;
239                 frame->v4l2_buf.flags |= V4L2_BUF_FLAG_DONE;
240                 atomic_inc(&gspca_dev->nevent);
241                 wake_up_interruptible(&gspca_dev->wq);  /* event = new frame */
242                 i = (gspca_dev->fr_i + 1) % gspca_dev->nframes;
243                 gspca_dev->fr_i = i;
244                 PDEBUG(D_FRAM, "frame complete len:%d q:%d i:%d o:%d",
245                         frame->v4l2_buf.bytesused,
246                         gspca_dev->fr_q,
247                         i,
248                         gspca_dev->fr_o);
249                 j = gspca_dev->fr_queue[i];
250                 frame = &gspca_dev->frame[j];
251         }
252         return frame;
253 }
254 EXPORT_SYMBOL(gspca_frame_add);
255
256 static int gspca_is_compressed(__u32 format)
257 {
258         switch (format) {
259         case V4L2_PIX_FMT_MJPEG:
260         case V4L2_PIX_FMT_JPEG:
261         case V4L2_PIX_FMT_SPCA561:
262         case V4L2_PIX_FMT_PAC207:
263                 return 1;
264         }
265         return 0;
266 }
267
268 static void *rvmalloc(unsigned long size)
269 {
270         void *mem;
271         unsigned long adr;
272
273 /*      size = PAGE_ALIGN(size);        (already done) */
274         mem = vmalloc_32(size);
275         if (mem != NULL) {
276                 adr = (unsigned long) mem;
277                 while ((long) size > 0) {
278                         SetPageReserved(vmalloc_to_page((void *) adr));
279                         adr += PAGE_SIZE;
280                         size -= PAGE_SIZE;
281                 }
282         }
283         return mem;
284 }
285
286 static void rvfree(void *mem, long size)
287 {
288         unsigned long adr;
289
290         adr = (unsigned long) mem;
291         while (size > 0) {
292                 ClearPageReserved(vmalloc_to_page((void *) adr));
293                 adr += PAGE_SIZE;
294                 size -= PAGE_SIZE;
295         }
296         vfree(mem);
297 }
298
299 static int frame_alloc(struct gspca_dev *gspca_dev,
300                         unsigned int count)
301 {
302         struct gspca_frame *frame;
303         unsigned int frsz;
304         int i;
305
306         i = gspca_dev->curr_mode;
307         frsz = gspca_dev->cam.cam_mode[i].sizeimage;
308         PDEBUG(D_STREAM, "frame alloc frsz: %d", frsz);
309         frsz = PAGE_ALIGN(frsz);
310         gspca_dev->frsz = frsz;
311         if (count > GSPCA_MAX_FRAMES)
312                 count = GSPCA_MAX_FRAMES;
313         gspca_dev->frbuf = rvmalloc(frsz * count);
314         if (!gspca_dev->frbuf) {
315                 err("frame alloc failed");
316                 return -ENOMEM;
317         }
318         gspca_dev->nframes = count;
319         for (i = 0; i < count; i++) {
320                 frame = &gspca_dev->frame[i];
321                 frame->v4l2_buf.index = i;
322                 frame->v4l2_buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
323                 frame->v4l2_buf.flags = 0;
324                 frame->v4l2_buf.field = V4L2_FIELD_NONE;
325                 frame->v4l2_buf.length = frsz;
326                 frame->v4l2_buf.memory = gspca_dev->memory;
327                 frame->v4l2_buf.sequence = 0;
328                 frame->data = frame->data_end =
329                                         gspca_dev->frbuf + i * frsz;
330                 frame->v4l2_buf.m.offset = i * frsz;
331         }
332         gspca_dev->fr_i = gspca_dev->fr_o = gspca_dev->fr_q = 0;
333         gspca_dev->last_packet_type = DISCARD_PACKET;
334         gspca_dev->sequence = 0;
335         atomic_set(&gspca_dev->nevent, 0);
336         return 0;
337 }
338
339 static void frame_free(struct gspca_dev *gspca_dev)
340 {
341         int i;
342
343         PDEBUG(D_STREAM, "frame free");
344         if (gspca_dev->frbuf != NULL) {
345                 rvfree(gspca_dev->frbuf,
346                         gspca_dev->nframes * gspca_dev->frsz);
347                 gspca_dev->frbuf = NULL;
348                 for (i = 0; i < gspca_dev->nframes; i++)
349                         gspca_dev->frame[i].data = NULL;
350         }
351         gspca_dev->nframes = 0;
352 }
353
354 static void destroy_urbs(struct gspca_dev *gspca_dev)
355 {
356         struct urb *urb;
357         unsigned int i;
358
359         PDEBUG(D_STREAM, "kill transfer");
360         for (i = 0; i < MAX_NURBS; ++i) {
361                 urb = gspca_dev->urb[i];
362                 if (urb == NULL)
363                         break;
364
365                 gspca_dev->urb[i] = NULL;
366                 usb_kill_urb(urb);
367                 if (urb->transfer_buffer != NULL)
368                         usb_buffer_free(gspca_dev->dev,
369                                         urb->transfer_buffer_length,
370                                         urb->transfer_buffer,
371                                         urb->transfer_dma);
372                 usb_free_urb(urb);
373         }
374 }
375
376 /*
377  * search an input isochronous endpoint in an alternate setting
378  */
379 static struct usb_host_endpoint *alt_isoc(struct usb_host_interface *alt,
380                                           __u8 epaddr)
381 {
382         struct usb_host_endpoint *ep;
383         int i, attr;
384
385         epaddr |= USB_DIR_IN;
386         for (i = 0; i < alt->desc.bNumEndpoints; i++) {
387                 ep = &alt->endpoint[i];
388                 if (ep->desc.bEndpointAddress == epaddr) {
389                         attr = ep->desc.bmAttributes
390                                                 & USB_ENDPOINT_XFERTYPE_MASK;
391                         if (attr == USB_ENDPOINT_XFER_ISOC)
392                                 return ep;
393                         break;
394                 }
395         }
396         return NULL;
397 }
398
399 /*
400  * search an input isochronous endpoint
401  *
402  * The endpoint is defined by the subdriver.
403  * Use only the first isoc (some Zoran - 0x0572:0x0001 - have two such ep).
404  * This routine may be called many times when the bandwidth is too small
405  * (the bandwidth is checked on urb submit).
406  */
407 static struct usb_host_endpoint *get_isoc_ep(struct gspca_dev *gspca_dev)
408 {
409         struct usb_interface *intf;
410         struct usb_host_endpoint *ep;
411         int i, ret;
412
413         intf = usb_ifnum_to_if(gspca_dev->dev, gspca_dev->iface);
414         ep = NULL;
415         i = gspca_dev->alt;                     /* previous alt setting */
416         while (--i > 0) {                       /* alt 0 is unusable */
417                 ep = alt_isoc(&intf->altsetting[i], gspca_dev->cam.epaddr);
418                 if (ep)
419                         break;
420         }
421         if (ep == NULL) {
422                 err("no ISOC endpoint found");
423                 return NULL;
424         }
425         PDEBUG(D_STREAM, "use ISOC alt %d ep 0x%02x",
426                         i, ep->desc.bEndpointAddress);
427         ret = usb_set_interface(gspca_dev->dev, gspca_dev->iface, i);
428         if (ret < 0) {
429                 err("set interface err %d", ret);
430                 return NULL;
431         }
432         gspca_dev->alt = i;             /* memorize the current alt setting */
433         return ep;
434 }
435
436 /*
437  * create the isochronous URBs
438  */
439 static int create_urbs(struct gspca_dev *gspca_dev,
440                         struct usb_host_endpoint *ep)
441 {
442         struct urb *urb;
443         int n, nurbs, i, psize, npkt, bsize;
444
445         /* calculate the packet size and the number of packets */
446         psize = le16_to_cpu(ep->desc.wMaxPacketSize);
447
448         /* See paragraph 5.9 / table 5-11 of the usb 2.0 spec. */
449         psize = (psize & 0x07ff) * (1 + ((psize >> 11) & 3));
450         npkt = ISO_MAX_SIZE / psize;
451         if (npkt > ISO_MAX_PKT)
452                 npkt = ISO_MAX_PKT;
453         bsize = psize * npkt;
454         PDEBUG(D_STREAM,
455                 "isoc %d pkts size %d (bsize:%d)", npkt, psize, bsize);
456         nurbs = DEF_NURBS;
457         gspca_dev->nurbs = nurbs;
458         for (n = 0; n < nurbs; n++) {
459                 urb = usb_alloc_urb(npkt, GFP_KERNEL);
460                 if (!urb) {
461                         err("usb_alloc_urb failed");
462                         return -ENOMEM;
463                 }
464                 urb->transfer_buffer = usb_buffer_alloc(gspca_dev->dev,
465                                                 bsize,
466                                                 GFP_KERNEL,
467                                                 &urb->transfer_dma);
468
469                 if (urb->transfer_buffer == NULL) {
470                         usb_free_urb(urb);
471                         destroy_urbs(gspca_dev);
472                         err("usb_buffer_urb failed");
473                         return -ENOMEM;
474                 }
475                 gspca_dev->urb[n] = urb;
476                 urb->dev = gspca_dev->dev;
477                 urb->context = gspca_dev;
478                 urb->pipe = usb_rcvisocpipe(gspca_dev->dev,
479                                             ep->desc.bEndpointAddress);
480                 urb->transfer_flags = URB_ISO_ASAP
481                                         | URB_NO_TRANSFER_DMA_MAP;
482                 urb->interval = ep->desc.bInterval;
483                 urb->complete = isoc_irq;
484                 urb->number_of_packets = npkt;
485                 urb->transfer_buffer_length = bsize;
486                 for (i = 0; i < npkt; i++) {
487                         urb->iso_frame_desc[i].length = psize;
488                         urb->iso_frame_desc[i].offset = psize * i;
489                 }
490         }
491         return 0;
492 }
493
494 /*
495  * start the USB transfer
496  */
497 static int gspca_init_transfer(struct gspca_dev *gspca_dev)
498 {
499         struct usb_host_endpoint *ep;
500         int n, ret;
501
502         if (mutex_lock_interruptible(&gspca_dev->usb_lock))
503                 return -ERESTARTSYS;
504
505         /* set the higher alternate setting and
506          * loop until urb submit succeeds */
507         gspca_dev->alt = gspca_dev->nbalt;
508         for (;;) {
509                 PDEBUG(D_STREAM, "init transfer alt %d", gspca_dev->alt);
510                 ep = get_isoc_ep(gspca_dev);
511                 if (ep == NULL) {
512                         ret = -EIO;
513                         goto out;
514                 }
515                 ret = create_urbs(gspca_dev, ep);
516                 if (ret < 0)
517                         goto out;
518
519                 /* start the cam */
520                 gspca_dev->sd_desc->start(gspca_dev);
521                 gspca_dev->streaming = 1;
522                 atomic_set(&gspca_dev->nevent, 0);
523
524                 /* submit the URBs */
525                 for (n = 0; n < gspca_dev->nurbs; n++) {
526                         ret = usb_submit_urb(gspca_dev->urb[n], GFP_KERNEL);
527                         if (ret < 0) {
528                                 PDEBUG(D_ERR|D_STREAM,
529                                         "usb_submit_urb [%d] err %d", n, ret);
530                                 gspca_dev->streaming = 0;
531                                 destroy_urbs(gspca_dev);
532                                 if (ret == -ENOSPC)
533                                         break;  /* try the previous alt */
534                                 goto out;
535                         }
536                 }
537                 if (ret >= 0)
538                         break;
539         }
540 out:
541         mutex_unlock(&gspca_dev->usb_lock);
542         return ret;
543 }
544
545 static int gspca_set_alt0(struct gspca_dev *gspca_dev)
546 {
547         int ret;
548
549         ret = usb_set_interface(gspca_dev->dev, gspca_dev->iface, 0);
550         if (ret < 0)
551                 PDEBUG(D_ERR|D_STREAM, "set interface 0 err %d", ret);
552         return ret;
553 }
554
555 /* Note both the queue and the usb lock should be hold when calling this */
556 static void gspca_stream_off(struct gspca_dev *gspca_dev)
557 {
558         gspca_dev->streaming = 0;
559         atomic_set(&gspca_dev->nevent, 0);
560         if (gspca_dev->present) {
561                 if (gspca_dev->sd_desc->stopN)
562                         gspca_dev->sd_desc->stopN(gspca_dev);
563                 destroy_urbs(gspca_dev);
564                 gspca_set_alt0(gspca_dev);
565                 if (gspca_dev->sd_desc->stop0)
566                         gspca_dev->sd_desc->stop0(gspca_dev);
567                 PDEBUG(D_STREAM, "stream off OK");
568         }
569 }
570
571 static void gspca_set_default_mode(struct gspca_dev *gspca_dev)
572 {
573         int i;
574
575         i = gspca_dev->cam.nmodes - 1;  /* take the highest mode */
576         gspca_dev->curr_mode = i;
577         gspca_dev->width = gspca_dev->cam.cam_mode[i].width;
578         gspca_dev->height = gspca_dev->cam.cam_mode[i].height;
579         gspca_dev->pixfmt = gspca_dev->cam.cam_mode[i].pixelformat;
580 }
581
582 static int wxh_to_mode(struct gspca_dev *gspca_dev,
583                         int width, int height)
584 {
585         int i;
586
587         for (i = gspca_dev->cam.nmodes; --i > 0; ) {
588                 if (width >= gspca_dev->cam.cam_mode[i].width
589                     && height >= gspca_dev->cam.cam_mode[i].height)
590                         break;
591         }
592         return i;
593 }
594
595 /*
596  * search a mode with the right pixel format
597  */
598 static int gspca_get_mode(struct gspca_dev *gspca_dev,
599                         int mode,
600                         int pixfmt)
601 {
602         int modeU, modeD;
603
604         modeU = modeD = mode;
605         while ((modeU < gspca_dev->cam.nmodes) || modeD >= 0) {
606                 if (--modeD >= 0) {
607                         if (gspca_dev->cam.cam_mode[modeD].pixelformat
608                                                                 == pixfmt)
609                                 return modeD;
610                 }
611                 if (++modeU < gspca_dev->cam.nmodes) {
612                         if (gspca_dev->cam.cam_mode[modeU].pixelformat
613                                                                 == pixfmt)
614                                 return modeU;
615                 }
616         }
617         return -EINVAL;
618 }
619
620 static int vidioc_enum_fmt_vid_cap(struct file *file, void  *priv,
621                                 struct v4l2_fmtdesc *fmtdesc)
622 {
623         struct gspca_dev *gspca_dev = priv;
624         int i, j, index;
625         __u32 fmt_tb[8];
626
627         /* give an index to each format */
628         index = 0;
629         j = 0;
630         for (i = gspca_dev->cam.nmodes; --i >= 0; ) {
631                 fmt_tb[index] = gspca_dev->cam.cam_mode[i].pixelformat;
632                 j = 0;
633                 for (;;) {
634                         if (fmt_tb[j] == fmt_tb[index])
635                                 break;
636                         j++;
637                 }
638                 if (j == index) {
639                         if (fmtdesc->index == index)
640                                 break;          /* new format */
641                         index++;
642                         if (index >= sizeof fmt_tb / sizeof fmt_tb[0])
643                                 return -EINVAL;
644                 }
645         }
646         if (i < 0)
647                 return -EINVAL;         /* no more format */
648
649         fmtdesc->pixelformat = fmt_tb[index];
650         if (gspca_is_compressed(fmt_tb[index]))
651                 fmtdesc->flags = V4L2_FMT_FLAG_COMPRESSED;
652         fmtdesc->type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
653         fmtdesc->description[0] = fmtdesc->pixelformat & 0xff;
654         fmtdesc->description[1] = (fmtdesc->pixelformat >> 8) & 0xff;
655         fmtdesc->description[2] = (fmtdesc->pixelformat >> 16) & 0xff;
656         fmtdesc->description[3] = fmtdesc->pixelformat >> 24;
657         fmtdesc->description[4] = '\0';
658         return 0;
659 }
660
661 static int vidioc_g_fmt_vid_cap(struct file *file, void *priv,
662                             struct v4l2_format *fmt)
663 {
664         struct gspca_dev *gspca_dev = priv;
665         int mode;
666
667         if (fmt->type != V4L2_BUF_TYPE_VIDEO_CAPTURE)
668                 return -EINVAL;
669         mode = gspca_dev->curr_mode;
670         memcpy(&fmt->fmt.pix, &gspca_dev->cam.cam_mode[mode],
671                 sizeof fmt->fmt.pix);
672         return 0;
673 }
674
675 static int try_fmt_vid_cap(struct gspca_dev *gspca_dev,
676                         struct v4l2_format *fmt)
677 {
678         int w, h, mode, mode2;
679
680         if (fmt->type != V4L2_BUF_TYPE_VIDEO_CAPTURE)
681                 return -EINVAL;
682         w = fmt->fmt.pix.width;
683         h = fmt->fmt.pix.height;
684
685 #ifdef GSPCA_DEBUG
686         if (gspca_debug & D_CONF)
687                 PDEBUG_MODE("try fmt cap", fmt->fmt.pix.pixelformat, w, h);
688 #endif
689         /* search the closest mode for width and height */
690         mode = wxh_to_mode(gspca_dev, w, h);
691
692         /* OK if right palette */
693         if (gspca_dev->cam.cam_mode[mode].pixelformat
694                                                 != fmt->fmt.pix.pixelformat) {
695
696                 /* else, search the closest mode with the same pixel format */
697                 mode2 = gspca_get_mode(gspca_dev, mode,
698                                         fmt->fmt.pix.pixelformat);
699                 if (mode2 >= 0)
700                         mode = mode2;
701 /*              else
702                         ;                * no chance, return this mode */
703         }
704         memcpy(&fmt->fmt.pix, &gspca_dev->cam.cam_mode[mode],
705                 sizeof fmt->fmt.pix);
706         return mode;                    /* used when s_fmt */
707 }
708
709 static int vidioc_try_fmt_vid_cap(struct file *file,
710                               void *priv,
711                               struct v4l2_format *fmt)
712 {
713         struct gspca_dev *gspca_dev = priv;
714         int ret;
715
716         ret = try_fmt_vid_cap(gspca_dev, fmt);
717         if (ret < 0)
718                 return ret;
719         return 0;
720 }
721
722 static int vidioc_s_fmt_vid_cap(struct file *file, void *priv,
723                             struct v4l2_format *fmt)
724 {
725         struct gspca_dev *gspca_dev = priv;
726         int ret;
727
728         if (mutex_lock_interruptible(&gspca_dev->queue_lock))
729                 return -ERESTARTSYS;
730
731         ret = try_fmt_vid_cap(gspca_dev, fmt);
732         if (ret < 0)
733                 goto out;
734
735         if (gspca_dev->nframes != 0
736             && fmt->fmt.pix.sizeimage > gspca_dev->frsz) {
737                 ret = -EINVAL;
738                 goto out;
739         }
740
741         if (ret == gspca_dev->curr_mode) {
742                 ret = 0;
743                 goto out;                       /* same mode */
744         }
745
746         if (gspca_dev->streaming) {
747                 ret = -EBUSY;
748                 goto out;
749         }
750         gspca_dev->width = fmt->fmt.pix.width;
751         gspca_dev->height = fmt->fmt.pix.height;
752         gspca_dev->pixfmt = fmt->fmt.pix.pixelformat;
753         gspca_dev->curr_mode = ret;
754
755         ret = 0;
756 out:
757         mutex_unlock(&gspca_dev->queue_lock);
758         return ret;
759 }
760
761 static int dev_open(struct inode *inode, struct file *file)
762 {
763         struct gspca_dev *gspca_dev;
764         int ret;
765
766         PDEBUG(D_STREAM, "%s open", current->comm);
767         gspca_dev = (struct gspca_dev *) video_devdata(file);
768         if (mutex_lock_interruptible(&gspca_dev->queue_lock))
769                 return -ERESTARTSYS;
770         if (!gspca_dev->present) {
771                 ret = -ENODEV;
772                 goto out;
773         }
774
775         if (gspca_dev->users > 4) {     /* (arbitrary value) */
776                 ret = -EBUSY;
777                 goto out;
778         }
779         gspca_dev->users++;
780         file->private_data = gspca_dev;
781 #ifdef GSPCA_DEBUG
782         /* activate the v4l2 debug */
783         if (gspca_debug & D_V4L2)
784                 gspca_dev->vdev.debug |= 3;
785         else
786                 gspca_dev->vdev.debug &= ~3;
787 #endif
788         ret = 0;
789 out:
790         mutex_unlock(&gspca_dev->queue_lock);
791         if (ret != 0)
792                 PDEBUG(D_ERR|D_STREAM, "open failed err %d", ret);
793         else
794                 PDEBUG(D_STREAM, "open done");
795         return ret;
796 }
797
798 static int dev_close(struct inode *inode, struct file *file)
799 {
800         struct gspca_dev *gspca_dev = file->private_data;
801
802         PDEBUG(D_STREAM, "%s close", current->comm);
803         if (mutex_lock_interruptible(&gspca_dev->queue_lock))
804                 return -ERESTARTSYS;
805         gspca_dev->users--;
806
807         /* if the file did the capture, free the streaming resources */
808         if (gspca_dev->capt_file == file) {
809                 if (gspca_dev->streaming) {
810                         mutex_lock(&gspca_dev->usb_lock);
811                         gspca_stream_off(gspca_dev);
812                         mutex_unlock(&gspca_dev->usb_lock);
813                 }
814                 frame_free(gspca_dev);
815                 gspca_dev->capt_file = NULL;
816                 gspca_dev->memory = GSPCA_MEMORY_NO;
817         }
818         file->private_data = NULL;
819         mutex_unlock(&gspca_dev->queue_lock);
820         PDEBUG(D_STREAM, "close done");
821         return 0;
822 }
823
824 static int vidioc_querycap(struct file *file, void  *priv,
825                            struct v4l2_capability *cap)
826 {
827         struct gspca_dev *gspca_dev = priv;
828
829         memset(cap, 0, sizeof *cap);
830         strncpy(cap->driver, gspca_dev->sd_desc->name, sizeof cap->driver);
831 /*      strncpy(cap->card, gspca_dev->cam.dev_name, sizeof cap->card); */
832         if (gspca_dev->dev->product != NULL) {
833                 strncpy(cap->card, gspca_dev->dev->product,
834                         sizeof cap->card);
835         } else {
836                 snprintf(cap->card, sizeof cap->card,
837                         "USB Camera (%04x:%04x)",
838                         le16_to_cpu(gspca_dev->dev->descriptor.idVendor),
839                         le16_to_cpu(gspca_dev->dev->descriptor.idProduct));
840         }
841         strncpy(cap->bus_info, gspca_dev->dev->bus->bus_name,
842                 sizeof cap->bus_info);
843         cap->version = DRIVER_VERSION_NUMBER;
844         cap->capabilities = V4L2_CAP_VIDEO_CAPTURE
845                           | V4L2_CAP_STREAMING
846                           | V4L2_CAP_READWRITE;
847         return 0;
848 }
849
850 static int vidioc_queryctrl(struct file *file, void *priv,
851                            struct v4l2_queryctrl *q_ctrl)
852 {
853         struct gspca_dev *gspca_dev = priv;
854         int i, ix;
855         u32 id;
856
857         ix = -1;
858         id = q_ctrl->id;
859         if (id & V4L2_CTRL_FLAG_NEXT_CTRL) {
860                 id &= V4L2_CTRL_ID_MASK;
861                 id++;
862                 for (i = 0; i < gspca_dev->sd_desc->nctrls; i++) {
863                         if (gspca_dev->sd_desc->ctrls[i].qctrl.id < id)
864                                 continue;
865                         if (ix < 0) {
866                                 ix = i;
867                                 continue;
868                         }
869                         if (gspca_dev->sd_desc->ctrls[i].qctrl.id
870                                     > gspca_dev->sd_desc->ctrls[ix].qctrl.id)
871                                 continue;
872                         ix = i;
873                 }
874         }
875         for (i = 0; i < gspca_dev->sd_desc->nctrls; i++) {
876                 if (id == gspca_dev->sd_desc->ctrls[i].qctrl.id) {
877                         ix = i;
878                         break;
879                 }
880         }
881         if (ix < 0)
882                 return -EINVAL;
883         memcpy(q_ctrl, &gspca_dev->sd_desc->ctrls[ix].qctrl,
884                 sizeof *q_ctrl);
885         if (gspca_dev->ctrl_dis & (1 << ix))
886                 q_ctrl->flags |= V4L2_CTRL_FLAG_DISABLED;
887         return 0;
888 }
889
890 static int vidioc_s_ctrl(struct file *file, void *priv,
891                          struct v4l2_control *ctrl)
892 {
893         struct gspca_dev *gspca_dev = priv;
894         const struct ctrl *ctrls;
895         int i, ret;
896
897         for (i = 0, ctrls = gspca_dev->sd_desc->ctrls;
898              i < gspca_dev->sd_desc->nctrls;
899              i++, ctrls++) {
900                 if (ctrl->id != ctrls->qctrl.id)
901                         continue;
902                 if (gspca_dev->ctrl_dis & (1 << i))
903                         return -EINVAL;
904                 if (ctrl->value < ctrls->qctrl.minimum
905                     || ctrl->value > ctrls->qctrl.maximum)
906                         return -ERANGE;
907                 PDEBUG(D_CONF, "set ctrl [%08x] = %d", ctrl->id, ctrl->value);
908                 if (mutex_lock_interruptible(&gspca_dev->usb_lock))
909                         return -ERESTARTSYS;
910                 ret = ctrls->set(gspca_dev, ctrl->value);
911                 mutex_unlock(&gspca_dev->usb_lock);
912                 return ret;
913         }
914         return -EINVAL;
915 }
916
917 static int vidioc_g_ctrl(struct file *file, void *priv,
918                          struct v4l2_control *ctrl)
919 {
920         struct gspca_dev *gspca_dev = priv;
921
922         const struct ctrl *ctrls;
923         int i, ret;
924
925         for (i = 0, ctrls = gspca_dev->sd_desc->ctrls;
926              i < gspca_dev->sd_desc->nctrls;
927              i++, ctrls++) {
928                 if (ctrl->id != ctrls->qctrl.id)
929                         continue;
930                 if (gspca_dev->ctrl_dis & (1 << i))
931                         return -EINVAL;
932                 if (mutex_lock_interruptible(&gspca_dev->usb_lock))
933                         return -ERESTARTSYS;
934                 ret = ctrls->get(gspca_dev, &ctrl->value);
935                 mutex_unlock(&gspca_dev->usb_lock);
936                 return ret;
937         }
938         return -EINVAL;
939 }
940
941 static int vidioc_querymenu(struct file *file, void *priv,
942                             struct v4l2_querymenu *qmenu)
943 {
944         struct gspca_dev *gspca_dev = priv;
945
946         if (!gspca_dev->sd_desc->querymenu)
947                 return -EINVAL;
948         return gspca_dev->sd_desc->querymenu(gspca_dev, qmenu);
949 }
950
951 static int vidioc_enum_input(struct file *file, void *priv,
952                                 struct v4l2_input *input)
953 {
954         struct gspca_dev *gspca_dev = priv;
955
956         if (input->index != 0)
957                 return -EINVAL;
958         memset(input, 0, sizeof *input);
959         input->type = V4L2_INPUT_TYPE_CAMERA;
960         strncpy(input->name, gspca_dev->sd_desc->name,
961                 sizeof input->name);
962         return 0;
963 }
964
965 static int vidioc_g_input(struct file *file, void *priv, unsigned int *i)
966 {
967         *i = 0;
968         return 0;
969 }
970
971 static int vidioc_s_input(struct file *file, void *priv, unsigned int i)
972 {
973         if (i > 0)
974                 return -EINVAL;
975         return (0);
976 }
977
978 static int vidioc_reqbufs(struct file *file, void *priv,
979                           struct v4l2_requestbuffers *rb)
980 {
981         struct gspca_dev *gspca_dev = priv;
982         int i, ret = 0;
983
984         if (rb->type != V4L2_BUF_TYPE_VIDEO_CAPTURE)
985                 return -EINVAL;
986         switch (rb->memory) {
987         case GSPCA_MEMORY_READ:                 /* (internal call) */
988         case V4L2_MEMORY_MMAP:
989         case V4L2_MEMORY_USERPTR:
990                 break;
991         default:
992                 return -EINVAL;
993         }
994         if (mutex_lock_interruptible(&gspca_dev->queue_lock))
995                 return -ERESTARTSYS;
996
997         if (gspca_dev->memory != GSPCA_MEMORY_NO
998             && gspca_dev->memory != rb->memory) {
999                 ret = -EBUSY;
1000                 goto out;
1001         }
1002
1003         /* only one file may do the capture */
1004         if (gspca_dev->capt_file != NULL
1005             && gspca_dev->capt_file != file) {
1006                 ret = -EBUSY;
1007                 goto out;
1008         }
1009
1010         /* if allocated, the buffers must not be mapped */
1011         for (i = 0; i < gspca_dev->nframes; i++) {
1012                 if (gspca_dev->frame[i].vma_use_count) {
1013                         ret = -EBUSY;
1014                         goto out;
1015                 }
1016         }
1017
1018         /* stop streaming */
1019         if (gspca_dev->streaming) {
1020                 mutex_lock(&gspca_dev->usb_lock);
1021                 gspca_stream_off(gspca_dev);
1022                 mutex_unlock(&gspca_dev->usb_lock);
1023         }
1024
1025         /* free the previous allocated buffers, if any */
1026         if (gspca_dev->nframes != 0) {
1027                 frame_free(gspca_dev);
1028                 gspca_dev->capt_file = NULL;
1029         }
1030         if (rb->count == 0)                     /* unrequest */
1031                 goto out;
1032         gspca_dev->memory = rb->memory;
1033         ret = frame_alloc(gspca_dev, rb->count);
1034         if (ret == 0) {
1035                 rb->count = gspca_dev->nframes;
1036                 gspca_dev->capt_file = file;
1037         }
1038 out:
1039         mutex_unlock(&gspca_dev->queue_lock);
1040         PDEBUG(D_STREAM, "reqbufs st:%d c:%d", ret, rb->count);
1041         return ret;
1042 }
1043
1044 static int vidioc_querybuf(struct file *file, void *priv,
1045                            struct v4l2_buffer *v4l2_buf)
1046 {
1047         struct gspca_dev *gspca_dev = priv;
1048         struct gspca_frame *frame;
1049
1050         if (v4l2_buf->type != V4L2_BUF_TYPE_VIDEO_CAPTURE
1051             || v4l2_buf->index < 0
1052             || v4l2_buf->index >= gspca_dev->nframes)
1053                 return -EINVAL;
1054
1055         frame = &gspca_dev->frame[v4l2_buf->index];
1056         memcpy(v4l2_buf, &frame->v4l2_buf, sizeof *v4l2_buf);
1057         return 0;
1058 }
1059
1060 static int vidioc_streamon(struct file *file, void *priv,
1061                            enum v4l2_buf_type buf_type)
1062 {
1063         struct gspca_dev *gspca_dev = priv;
1064         int ret;
1065
1066         if (buf_type != V4L2_BUF_TYPE_VIDEO_CAPTURE)
1067                 return -EINVAL;
1068         if (mutex_lock_interruptible(&gspca_dev->queue_lock))
1069                 return -ERESTARTSYS;
1070         if (!gspca_dev->present) {
1071                 ret = -ENODEV;
1072                 goto out;
1073         }
1074         if (gspca_dev->nframes == 0) {
1075                 ret = -EINVAL;
1076                 goto out;
1077         }
1078         if (!gspca_dev->streaming) {
1079                 ret = gspca_init_transfer(gspca_dev);
1080                 if (ret < 0)
1081                         goto out;
1082         }
1083 #ifdef GSPCA_DEBUG
1084         if (gspca_debug & D_STREAM) {
1085                 PDEBUG_MODE("stream on OK",
1086                         gspca_dev->pixfmt,
1087                         gspca_dev->width,
1088                         gspca_dev->height);
1089         }
1090 #endif
1091         ret = 0;
1092 out:
1093         mutex_unlock(&gspca_dev->queue_lock);
1094         return ret;
1095 }
1096
1097 static int vidioc_streamoff(struct file *file, void *priv,
1098                                 enum v4l2_buf_type buf_type)
1099 {
1100         struct gspca_dev *gspca_dev = priv;
1101         int i, ret;
1102
1103         if (buf_type != V4L2_BUF_TYPE_VIDEO_CAPTURE)
1104                 return -EINVAL;
1105         if (!gspca_dev->streaming)
1106                 return 0;
1107         if (mutex_lock_interruptible(&gspca_dev->queue_lock))
1108                 return -ERESTARTSYS;
1109
1110         /* stop streaming */
1111         if (mutex_lock_interruptible(&gspca_dev->usb_lock)) {
1112                 ret = -ERESTARTSYS;
1113                 goto out;
1114         }
1115         gspca_stream_off(gspca_dev);
1116         mutex_unlock(&gspca_dev->usb_lock);
1117
1118         /* empty the application queues */
1119         for (i = 0; i < gspca_dev->nframes; i++)
1120                 gspca_dev->frame[i].v4l2_buf.flags &= ~BUF_ALL_FLAGS;
1121         gspca_dev->fr_i = gspca_dev->fr_o = gspca_dev->fr_q = 0;
1122         gspca_dev->last_packet_type = DISCARD_PACKET;
1123         gspca_dev->sequence = 0;
1124         atomic_set(&gspca_dev->nevent, 0);
1125         ret = 0;
1126 out:
1127         mutex_unlock(&gspca_dev->queue_lock);
1128         return ret;
1129 }
1130
1131 static int vidioc_g_jpegcomp(struct file *file, void *priv,
1132                         struct v4l2_jpegcompression *jpegcomp)
1133 {
1134         struct gspca_dev *gspca_dev = priv;
1135         int ret;
1136
1137         if (!gspca_dev->sd_desc->get_jcomp)
1138                 return -EINVAL;
1139         if (mutex_lock_interruptible(&gspca_dev->usb_lock))
1140                 return -ERESTARTSYS;
1141         ret = gspca_dev->sd_desc->get_jcomp(gspca_dev, jpegcomp);
1142         mutex_unlock(&gspca_dev->usb_lock);
1143         return ret;
1144 }
1145
1146 static int vidioc_s_jpegcomp(struct file *file, void *priv,
1147                         struct v4l2_jpegcompression *jpegcomp)
1148 {
1149         struct gspca_dev *gspca_dev = priv;
1150         int ret;
1151
1152         if (mutex_lock_interruptible(&gspca_dev->usb_lock))
1153                 return -ERESTARTSYS;
1154         if (!gspca_dev->sd_desc->set_jcomp)
1155                 return -EINVAL;
1156         ret = gspca_dev->sd_desc->set_jcomp(gspca_dev, jpegcomp);
1157         mutex_unlock(&gspca_dev->usb_lock);
1158         return ret;
1159 }
1160
1161 static int vidioc_g_parm(struct file *filp, void *priv,
1162                         struct v4l2_streamparm *parm)
1163 {
1164         struct gspca_dev *gspca_dev = priv;
1165
1166         memset(parm, 0, sizeof *parm);
1167         parm->type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
1168         parm->parm.capture.readbuffers = gspca_dev->nbufread;
1169         return 0;
1170 }
1171
1172 static int vidioc_s_parm(struct file *filp, void *priv,
1173                         struct v4l2_streamparm *parm)
1174 {
1175         struct gspca_dev *gspca_dev = priv;
1176         int n;
1177
1178         n = parm->parm.capture.readbuffers;
1179         if (n == 0 || n > GSPCA_MAX_FRAMES)
1180                 parm->parm.capture.readbuffers = gspca_dev->nbufread;
1181         else
1182                 gspca_dev->nbufread = n;
1183         return 0;
1184 }
1185
1186 static int vidioc_s_std(struct file *filp, void *priv,
1187                         v4l2_std_id *parm)
1188 {
1189         return 0;
1190 }
1191
1192 #ifdef CONFIG_VIDEO_V4L1_COMPAT
1193 static int vidiocgmbuf(struct file *file, void *priv,
1194                         struct video_mbuf *mbuf)
1195 {
1196         struct gspca_dev *gspca_dev = file->private_data;
1197         int i;
1198
1199         PDEBUG(D_STREAM, "cgmbuf");
1200         if (gspca_dev->nframes == 0) {
1201                 int ret;
1202
1203                 {
1204                         struct v4l2_format fmt;
1205
1206                         memset(&fmt, 0, sizeof fmt);
1207                         fmt.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
1208                         i = gspca_dev->cam.nmodes - 1;  /* highest mode */
1209                         fmt.fmt.pix.width = gspca_dev->cam.cam_mode[i].width;
1210                         fmt.fmt.pix.height = gspca_dev->cam.cam_mode[i].height;
1211                         fmt.fmt.pix.pixelformat = V4L2_PIX_FMT_BGR24;
1212                         ret = vidioc_s_fmt_vid_cap(file, priv, &fmt);
1213                         if (ret != 0)
1214                                 return ret;
1215                 }
1216                 {
1217                         struct v4l2_requestbuffers rb;
1218
1219                         memset(&rb, 0, sizeof rb);
1220                         rb.count = 4;
1221                         rb.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
1222                         rb.memory = V4L2_MEMORY_MMAP;
1223                         ret = vidioc_reqbufs(file, priv, &rb);
1224                         if (ret != 0)
1225                                 return ret;
1226                 }
1227         }
1228         mbuf->frames = gspca_dev->nframes;
1229         mbuf->size = gspca_dev->frsz * gspca_dev->nframes;
1230         for (i = 0; i < mbuf->frames; i++)
1231                 mbuf->offsets[i] = gspca_dev->frame[i].v4l2_buf.m.offset;
1232         return 0;
1233 }
1234 #endif
1235
1236 static int dev_mmap(struct file *file, struct vm_area_struct *vma)
1237 {
1238         struct gspca_dev *gspca_dev = file->private_data;
1239         struct gspca_frame *frame;
1240         struct page *page;
1241         unsigned long addr, start, size;
1242         int i, ret;
1243
1244         start = vma->vm_start;
1245         size = vma->vm_end - vma->vm_start;
1246         PDEBUG(D_STREAM, "mmap start:%08x size:%d", (int) start, (int) size);
1247
1248         if (mutex_lock_interruptible(&gspca_dev->queue_lock))
1249                 return -ERESTARTSYS;
1250         if (!gspca_dev->present) {
1251                 ret = -ENODEV;
1252                 goto out;
1253         }
1254         if (gspca_dev->capt_file != file) {
1255                 ret = -EINVAL;
1256                 goto out;
1257         }
1258
1259         frame = NULL;
1260         for (i = 0; i < gspca_dev->nframes; ++i) {
1261                 if (gspca_dev->frame[i].v4l2_buf.memory != V4L2_MEMORY_MMAP) {
1262                         PDEBUG(D_STREAM, "mmap bad memory type");
1263                         break;
1264                 }
1265                 if ((gspca_dev->frame[i].v4l2_buf.m.offset >> PAGE_SHIFT)
1266                                                 == vma->vm_pgoff) {
1267                         frame = &gspca_dev->frame[i];
1268                         break;
1269                 }
1270         }
1271         if (frame == NULL) {
1272                 PDEBUG(D_STREAM, "mmap no frame buffer found");
1273                 ret = -EINVAL;
1274                 goto out;
1275         }
1276 #ifdef CONFIG_VIDEO_V4L1_COMPAT
1277         /* v4l1 maps all the buffers */
1278         if (i != 0
1279             || size != frame->v4l2_buf.length * gspca_dev->nframes)
1280 #endif
1281             if (size != frame->v4l2_buf.length) {
1282                 PDEBUG(D_STREAM, "mmap bad size");
1283                 ret = -EINVAL;
1284                 goto out;
1285         }
1286
1287         /*
1288          * - VM_IO marks the area as being a mmaped region for I/O to a
1289          *   device. It also prevents the region from being core dumped.
1290          */
1291         vma->vm_flags |= VM_IO;
1292
1293         addr = (unsigned long) frame->data;
1294         while (size > 0) {
1295                 page = vmalloc_to_page((void *) addr);
1296                 ret = vm_insert_page(vma, start, page);
1297                 if (ret < 0)
1298                         goto out;
1299                 start += PAGE_SIZE;
1300                 addr += PAGE_SIZE;
1301                 size -= PAGE_SIZE;
1302         }
1303
1304         vma->vm_ops = &gspca_vm_ops;
1305         vma->vm_private_data = frame;
1306         gspca_vm_open(vma);
1307         ret = 0;
1308 out:
1309         mutex_unlock(&gspca_dev->queue_lock);
1310         return ret;
1311 }
1312
1313 /*
1314  * wait for a video frame
1315  *
1316  * If a frame is ready, its index is returned.
1317  */
1318 static int frame_wait(struct gspca_dev *gspca_dev,
1319                         int nonblock_ing)
1320 {
1321         struct gspca_frame *frame;
1322         int i, j, ret;
1323
1324         /* check if a frame is ready */
1325         i = gspca_dev->fr_o;
1326         j = gspca_dev->fr_queue[i];
1327         frame = &gspca_dev->frame[j];
1328         if (frame->v4l2_buf.flags & V4L2_BUF_FLAG_DONE) {
1329                 atomic_dec(&gspca_dev->nevent);
1330                 goto ok;
1331         }
1332         if (nonblock_ing)                       /* no frame yet */
1333                 return -EAGAIN;
1334
1335         /* wait till a frame is ready */
1336         for (;;) {
1337                 ret = wait_event_interruptible_timeout(gspca_dev->wq,
1338                                         atomic_read(&gspca_dev->nevent) > 0,
1339                                         msecs_to_jiffies(3000));
1340                 if (ret <= 0) {
1341                         if (ret < 0)
1342                                 return ret;     /* interrupt */
1343                         return -EIO;            /* timeout */
1344                 }
1345                 atomic_dec(&gspca_dev->nevent);
1346                 if (!gspca_dev->streaming || !gspca_dev->present)
1347                         return -EIO;
1348                 i = gspca_dev->fr_o;
1349                 j = gspca_dev->fr_queue[i];
1350                 frame = &gspca_dev->frame[j];
1351                 if (frame->v4l2_buf.flags & V4L2_BUF_FLAG_DONE)
1352                         break;
1353         }
1354 ok:
1355         gspca_dev->fr_o = (i + 1) % gspca_dev->nframes;
1356         PDEBUG(D_FRAM, "frame wait q:%d i:%d o:%d",
1357                 gspca_dev->fr_q,
1358                 gspca_dev->fr_i,
1359                 gspca_dev->fr_o);
1360
1361         if (gspca_dev->sd_desc->dq_callback) {
1362                 mutex_lock(&gspca_dev->usb_lock);
1363                 gspca_dev->sd_desc->dq_callback(gspca_dev);
1364                 mutex_unlock(&gspca_dev->usb_lock);
1365         }
1366         return j;
1367 }
1368
1369 /*
1370  * dequeue a video buffer
1371  *
1372  * If nonblock_ing is false, block until a buffer is available.
1373  */
1374 static int vidioc_dqbuf(struct file *file, void *priv,
1375                         struct v4l2_buffer *v4l2_buf)
1376 {
1377         struct gspca_dev *gspca_dev = priv;
1378         struct gspca_frame *frame;
1379         int i, ret;
1380
1381         PDEBUG(D_FRAM, "dqbuf");
1382         if (v4l2_buf->type != V4L2_BUF_TYPE_VIDEO_CAPTURE)
1383                 return -EINVAL;
1384         if (v4l2_buf->memory != gspca_dev->memory)
1385                 return -EINVAL;
1386
1387         /* if not streaming, be sure the application will not loop forever */
1388         if (!(file->f_flags & O_NONBLOCK)
1389             && !gspca_dev->streaming && gspca_dev->users == 1)
1390                 return -EINVAL;
1391
1392         /* only the capturing file may dequeue */
1393         if (gspca_dev->capt_file != file)
1394                 return -EINVAL;
1395
1396         /* only one dequeue / read at a time */
1397         if (mutex_lock_interruptible(&gspca_dev->read_lock))
1398                 return -ERESTARTSYS;
1399
1400         ret = frame_wait(gspca_dev, file->f_flags & O_NONBLOCK);
1401         if (ret < 0)
1402                 goto out;
1403         i = ret;                                /* frame index */
1404         frame = &gspca_dev->frame[i];
1405         if (gspca_dev->memory == V4L2_MEMORY_USERPTR) {
1406                 if (copy_to_user((__u8 __user *) frame->v4l2_buf.m.userptr,
1407                                  frame->data,
1408                                  frame->v4l2_buf.bytesused)) {
1409                         PDEBUG(D_ERR|D_STREAM,
1410                                 "dqbuf cp to user failed");
1411                         ret = -EFAULT;
1412                         goto out;
1413                 }
1414         }
1415         frame->v4l2_buf.flags &= ~V4L2_BUF_FLAG_DONE;
1416         memcpy(v4l2_buf, &frame->v4l2_buf, sizeof *v4l2_buf);
1417         PDEBUG(D_FRAM, "dqbuf %d", i);
1418         ret = 0;
1419 out:
1420         mutex_unlock(&gspca_dev->read_lock);
1421         return ret;
1422 }
1423
1424 /*
1425  * queue a video buffer
1426  *
1427  * Attempting to queue a buffer that has already been
1428  * queued will return -EINVAL.
1429  */
1430 static int vidioc_qbuf(struct file *file, void *priv,
1431                         struct v4l2_buffer *v4l2_buf)
1432 {
1433         struct gspca_dev *gspca_dev = priv;
1434         struct gspca_frame *frame;
1435         int i, index, ret;
1436
1437         PDEBUG(D_FRAM, "qbuf %d", v4l2_buf->index);
1438         if (v4l2_buf->type != V4L2_BUF_TYPE_VIDEO_CAPTURE)
1439                 return -EINVAL;
1440
1441         if (mutex_lock_interruptible(&gspca_dev->queue_lock))
1442                 return -ERESTARTSYS;
1443
1444         index = v4l2_buf->index;
1445         if ((unsigned) index >= gspca_dev->nframes) {
1446                 PDEBUG(D_FRAM,
1447                         "qbuf idx %d >= %d", index, gspca_dev->nframes);
1448                 ret = -EINVAL;
1449                 goto out;
1450         }
1451         if (v4l2_buf->memory != gspca_dev->memory) {
1452                 PDEBUG(D_FRAM, "qbuf bad memory type");
1453                 ret = -EINVAL;
1454                 goto out;
1455         }
1456
1457         frame = &gspca_dev->frame[index];
1458         if (frame->v4l2_buf.flags & BUF_ALL_FLAGS) {
1459                 PDEBUG(D_FRAM, "qbuf bad state");
1460                 ret = -EINVAL;
1461                 goto out;
1462         }
1463
1464         frame->v4l2_buf.flags |= V4L2_BUF_FLAG_QUEUED;
1465 /*      frame->v4l2_buf.flags &= ~V4L2_BUF_FLAG_DONE; */
1466
1467         if (frame->v4l2_buf.memory == V4L2_MEMORY_USERPTR) {
1468                 frame->v4l2_buf.m.userptr = v4l2_buf->m.userptr;
1469                 frame->v4l2_buf.length = v4l2_buf->length;
1470         }
1471
1472         /* put the buffer in the 'queued' queue */
1473         i = gspca_dev->fr_q;
1474         gspca_dev->fr_queue[i] = index;
1475         gspca_dev->fr_q = (i + 1) % gspca_dev->nframes;
1476         PDEBUG(D_FRAM, "qbuf q:%d i:%d o:%d",
1477                 gspca_dev->fr_q,
1478                 gspca_dev->fr_i,
1479                 gspca_dev->fr_o);
1480
1481         v4l2_buf->flags |= V4L2_BUF_FLAG_QUEUED;
1482         v4l2_buf->flags &= ~V4L2_BUF_FLAG_DONE;
1483         ret = 0;
1484 out:
1485         mutex_unlock(&gspca_dev->queue_lock);
1486         return ret;
1487 }
1488
1489 /*
1490  * allocate the resources for read()
1491  */
1492 static int read_alloc(struct gspca_dev *gspca_dev,
1493                         struct file *file)
1494 {
1495         struct v4l2_buffer v4l2_buf;
1496         int i, ret;
1497
1498         PDEBUG(D_STREAM, "read alloc");
1499         if (gspca_dev->nframes == 0) {
1500                 struct v4l2_requestbuffers rb;
1501
1502                 memset(&rb, 0, sizeof rb);
1503                 rb.count = gspca_dev->nbufread;
1504                 rb.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
1505                 rb.memory = GSPCA_MEMORY_READ;
1506                 ret = vidioc_reqbufs(file, gspca_dev, &rb);
1507                 if (ret != 0) {
1508                         PDEBUG(D_STREAM, "read reqbuf err %d", ret);
1509                         return ret;
1510                 }
1511                 memset(&v4l2_buf, 0, sizeof v4l2_buf);
1512                 v4l2_buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
1513                 v4l2_buf.memory = GSPCA_MEMORY_READ;
1514                 for (i = 0; i < gspca_dev->nbufread; i++) {
1515                         v4l2_buf.index = i;
1516                         ret = vidioc_qbuf(file, gspca_dev, &v4l2_buf);
1517                         if (ret != 0) {
1518                                 PDEBUG(D_STREAM, "read qbuf err: %d", ret);
1519                                 return ret;
1520                         }
1521                 }
1522                 gspca_dev->memory = GSPCA_MEMORY_READ;
1523         }
1524
1525         /* start streaming */
1526         ret = vidioc_streamon(file, gspca_dev, V4L2_BUF_TYPE_VIDEO_CAPTURE);
1527         if (ret != 0)
1528                 PDEBUG(D_STREAM, "read streamon err %d", ret);
1529         return ret;
1530 }
1531
1532 static unsigned int dev_poll(struct file *file, poll_table *wait)
1533 {
1534         struct gspca_dev *gspca_dev = file->private_data;
1535         int i, ret;
1536
1537         PDEBUG(D_FRAM, "poll");
1538
1539         poll_wait(file, &gspca_dev->wq, wait);
1540         if (!gspca_dev->present)
1541                 return POLLERR;
1542
1543         /* if reqbufs is not done, the user would use read() */
1544         if (gspca_dev->nframes == 0) {
1545                 if (gspca_dev->memory != GSPCA_MEMORY_NO)
1546                         return POLLERR;         /* not the 1st time */
1547                 ret = read_alloc(gspca_dev, file);
1548                 if (ret != 0)
1549                         return POLLERR;
1550         }
1551
1552         if (mutex_lock_interruptible(&gspca_dev->queue_lock) != 0)
1553                 return POLLERR;
1554         if (!gspca_dev->present) {
1555                 ret = POLLERR;
1556                 goto out;
1557         }
1558
1559         /* check the next incoming buffer */
1560         i = gspca_dev->fr_o;
1561         i = gspca_dev->fr_queue[i];
1562         if (gspca_dev->frame[i].v4l2_buf.flags & V4L2_BUF_FLAG_DONE)
1563                 ret = POLLIN | POLLRDNORM;      /* something to read */
1564         else
1565                 ret = 0;
1566 out:
1567         mutex_unlock(&gspca_dev->queue_lock);
1568         return ret;
1569 }
1570
1571 static ssize_t dev_read(struct file *file, char __user *data,
1572                     size_t count, loff_t *ppos)
1573 {
1574         struct gspca_dev *gspca_dev = file->private_data;
1575         struct gspca_frame *frame;
1576         struct v4l2_buffer v4l2_buf;
1577         struct timeval timestamp;
1578         int n, ret, ret2;
1579
1580         PDEBUG(D_FRAM, "read (%zd)", count);
1581         if (!gspca_dev->present)
1582                 return -ENODEV;
1583         switch (gspca_dev->memory) {
1584         case GSPCA_MEMORY_NO:                   /* first time */
1585                 ret = read_alloc(gspca_dev, file);
1586                 if (ret != 0)
1587                         return ret;
1588                 break;
1589         case GSPCA_MEMORY_READ:
1590                 if (gspca_dev->capt_file == file)
1591                         break;
1592                 /* fall thru */
1593         default:
1594                 return -EINVAL;
1595         }
1596
1597         /* get a frame */
1598         jiffies_to_timeval(get_jiffies_64(), &timestamp);
1599         timestamp.tv_sec--;
1600         n = 2;
1601         for (;;) {
1602                 memset(&v4l2_buf, 0, sizeof v4l2_buf);
1603                 v4l2_buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
1604                 v4l2_buf.memory = GSPCA_MEMORY_READ;
1605                 ret = vidioc_dqbuf(file, gspca_dev, &v4l2_buf);
1606                 if (ret != 0) {
1607                         PDEBUG(D_STREAM, "read dqbuf err %d", ret);
1608                         return ret;
1609                 }
1610
1611                 /* if the process slept for more than 1 second,
1612                  * get anewer frame */
1613                 frame = &gspca_dev->frame[v4l2_buf.index];
1614                 if (--n < 0)
1615                         break;                  /* avoid infinite loop */
1616                 if (frame->v4l2_buf.timestamp.tv_sec >= timestamp.tv_sec)
1617                         break;
1618                 ret = vidioc_qbuf(file, gspca_dev, &v4l2_buf);
1619                 if (ret != 0) {
1620                         PDEBUG(D_STREAM, "read qbuf err %d", ret);
1621                         return ret;
1622                 }
1623         }
1624
1625         /* copy the frame */
1626         if (count > frame->v4l2_buf.bytesused)
1627                 count = frame->v4l2_buf.bytesused;
1628         ret = copy_to_user(data, frame->data, count);
1629         if (ret != 0) {
1630                 PDEBUG(D_ERR|D_STREAM,
1631                         "read cp to user lack %d / %zd", ret, count);
1632                 ret = -EFAULT;
1633                 goto out;
1634         }
1635         ret = count;
1636 out:
1637         /* in each case, requeue the buffer */
1638         ret2 = vidioc_qbuf(file, gspca_dev, &v4l2_buf);
1639         if (ret2 != 0)
1640                 return ret2;
1641         return ret;
1642 }
1643
1644 static void dev_release(struct video_device *vfd)
1645 {
1646         /* nothing */
1647 }
1648
1649 static struct file_operations dev_fops = {
1650         .owner = THIS_MODULE,
1651         .open = dev_open,
1652         .release = dev_close,
1653         .read = dev_read,
1654         .mmap = dev_mmap,
1655         .ioctl = video_ioctl2,
1656 #ifdef CONFIG_COMPAT
1657         .compat_ioctl = v4l_compat_ioctl32,
1658 #endif
1659         .llseek = no_llseek,
1660         .poll   = dev_poll,
1661 };
1662
1663 static const struct v4l2_ioctl_ops dev_ioctl_ops = {
1664         .vidioc_querycap        = vidioc_querycap,
1665         .vidioc_dqbuf           = vidioc_dqbuf,
1666         .vidioc_qbuf            = vidioc_qbuf,
1667         .vidioc_enum_fmt_vid_cap = vidioc_enum_fmt_vid_cap,
1668         .vidioc_try_fmt_vid_cap = vidioc_try_fmt_vid_cap,
1669         .vidioc_g_fmt_vid_cap   = vidioc_g_fmt_vid_cap,
1670         .vidioc_s_fmt_vid_cap   = vidioc_s_fmt_vid_cap,
1671         .vidioc_streamon        = vidioc_streamon,
1672         .vidioc_queryctrl       = vidioc_queryctrl,
1673         .vidioc_g_ctrl          = vidioc_g_ctrl,
1674         .vidioc_s_ctrl          = vidioc_s_ctrl,
1675         .vidioc_querymenu       = vidioc_querymenu,
1676         .vidioc_enum_input      = vidioc_enum_input,
1677         .vidioc_g_input         = vidioc_g_input,
1678         .vidioc_s_input         = vidioc_s_input,
1679         .vidioc_reqbufs         = vidioc_reqbufs,
1680         .vidioc_querybuf        = vidioc_querybuf,
1681         .vidioc_streamoff       = vidioc_streamoff,
1682         .vidioc_g_jpegcomp      = vidioc_g_jpegcomp,
1683         .vidioc_s_jpegcomp      = vidioc_s_jpegcomp,
1684         .vidioc_g_parm          = vidioc_g_parm,
1685         .vidioc_s_parm          = vidioc_s_parm,
1686         .vidioc_s_std           = vidioc_s_std,
1687 #ifdef CONFIG_VIDEO_V4L1_COMPAT
1688         .vidiocgmbuf          = vidiocgmbuf,
1689 #endif
1690 };
1691
1692 static struct video_device gspca_template = {
1693         .name = "gspca main driver",
1694         .fops = &dev_fops,
1695         .ioctl_ops = &dev_ioctl_ops,
1696         .release = dev_release,         /* mandatory */
1697         .minor = -1,
1698 };
1699
1700 /*
1701  * probe and create a new gspca device
1702  *
1703  * This function must be called by the sub-driver when it is
1704  * called for probing a new device.
1705  */
1706 int gspca_dev_probe(struct usb_interface *intf,
1707                 const struct usb_device_id *id,
1708                 const struct sd_desc *sd_desc,
1709                 int dev_size,
1710                 struct module *module)
1711 {
1712         struct usb_interface_descriptor *interface;
1713         struct gspca_dev *gspca_dev;
1714         struct usb_device *dev = interface_to_usbdev(intf);
1715         int ret;
1716
1717         PDEBUG(D_PROBE, "probing %04x:%04x", id->idVendor, id->idProduct);
1718
1719         /* we don't handle multi-config cameras */
1720         if (dev->descriptor.bNumConfigurations != 1)
1721                 return -ENODEV;
1722         interface = &intf->cur_altsetting->desc;
1723         if (interface->bInterfaceNumber > 0)
1724                 return -ENODEV;
1725
1726         /* create the device */
1727         if (dev_size < sizeof *gspca_dev)
1728                 dev_size = sizeof *gspca_dev;
1729         gspca_dev = kzalloc(dev_size, GFP_KERNEL);
1730         if (gspca_dev == NULL) {
1731                 err("couldn't kzalloc gspca struct");
1732                 return -EIO;
1733         }
1734         gspca_dev->usb_buf = kmalloc(USB_BUF_SZ, GFP_KERNEL);
1735         if (!gspca_dev->usb_buf) {
1736                 err("out of memory");
1737                 ret = -EIO;
1738                 goto out;
1739         }
1740         gspca_dev->dev = dev;
1741         gspca_dev->iface = interface->bInterfaceNumber;
1742         gspca_dev->nbalt = intf->num_altsetting;
1743         gspca_dev->sd_desc = sd_desc;
1744 /*      gspca_dev->users = 0;                   (done by kzalloc) */
1745         gspca_dev->nbufread = 2;
1746
1747         /* configure the subdriver and initialize the USB device */
1748         ret = gspca_dev->sd_desc->config(gspca_dev, id);
1749         if (ret < 0)
1750                 goto out;
1751         ret = gspca_dev->sd_desc->init(gspca_dev);
1752         if (ret < 0)
1753                 goto out;
1754         ret = gspca_set_alt0(gspca_dev);
1755         if (ret < 0)
1756                 goto out;
1757         gspca_set_default_mode(gspca_dev);
1758
1759         mutex_init(&gspca_dev->usb_lock);
1760         mutex_init(&gspca_dev->read_lock);
1761         mutex_init(&gspca_dev->queue_lock);
1762         init_waitqueue_head(&gspca_dev->wq);
1763
1764         /* init video stuff */
1765         memcpy(&gspca_dev->vdev, &gspca_template, sizeof gspca_template);
1766         gspca_dev->vdev.parent = &dev->dev;
1767         memcpy(&gspca_dev->fops, &dev_fops, sizeof gspca_dev->fops);
1768         gspca_dev->vdev.fops = &gspca_dev->fops;
1769         gspca_dev->fops.owner = module;         /* module protection */
1770         gspca_dev->present = 1;
1771         ret = video_register_device(&gspca_dev->vdev,
1772                                   VFL_TYPE_GRABBER,
1773                                   video_nr);
1774         if (ret < 0) {
1775                 err("video_register_device err %d", ret);
1776                 goto out;
1777         }
1778
1779         usb_set_intfdata(intf, gspca_dev);
1780         PDEBUG(D_PROBE, "probe ok");
1781         return 0;
1782 out:
1783         kfree(gspca_dev->usb_buf);
1784         kfree(gspca_dev);
1785         return ret;
1786 }
1787 EXPORT_SYMBOL(gspca_dev_probe);
1788
1789 /*
1790  * USB disconnection
1791  *
1792  * This function must be called by the sub-driver
1793  * when the device disconnects, after the specific resources are freed.
1794  */
1795 void gspca_disconnect(struct usb_interface *intf)
1796 {
1797         struct gspca_dev *gspca_dev = usb_get_intfdata(intf);
1798
1799         if (!gspca_dev)
1800                 return;
1801         gspca_dev->present = 0;
1802         mutex_lock(&gspca_dev->queue_lock);
1803         mutex_lock(&gspca_dev->usb_lock);
1804         gspca_dev->streaming = 0;
1805         destroy_urbs(gspca_dev);
1806         mutex_unlock(&gspca_dev->usb_lock);
1807         mutex_unlock(&gspca_dev->queue_lock);
1808         while (gspca_dev->users != 0) {         /* wait until fully closed */
1809                 atomic_inc(&gspca_dev->nevent);
1810                 wake_up_interruptible(&gspca_dev->wq);  /* wake processes */
1811                 schedule();
1812         }
1813 /* We don't want people trying to open up the device */
1814         video_unregister_device(&gspca_dev->vdev);
1815 /* Free the memory */
1816         kfree(gspca_dev->usb_buf);
1817         kfree(gspca_dev);
1818         PDEBUG(D_PROBE, "disconnect complete");
1819 }
1820 EXPORT_SYMBOL(gspca_disconnect);
1821
1822 #ifdef CONFIG_PM
1823 int gspca_suspend(struct usb_interface *intf, pm_message_t message)
1824 {
1825         struct gspca_dev *gspca_dev = usb_get_intfdata(intf);
1826
1827         if (!gspca_dev->streaming)
1828                 return 0;
1829         gspca_dev->frozen = 1;          /* avoid urb error messages */
1830         if (gspca_dev->sd_desc->stopN)
1831                 gspca_dev->sd_desc->stopN(gspca_dev);
1832         destroy_urbs(gspca_dev);
1833         gspca_set_alt0(gspca_dev);
1834         if (gspca_dev->sd_desc->stop0)
1835                 gspca_dev->sd_desc->stop0(gspca_dev);
1836         return 0;
1837 }
1838 EXPORT_SYMBOL(gspca_suspend);
1839
1840 int gspca_resume(struct usb_interface *intf)
1841 {
1842         struct gspca_dev *gspca_dev = usb_get_intfdata(intf);
1843
1844         gspca_dev->frozen = 0;
1845         gspca_dev->sd_desc->init(gspca_dev);
1846         if (gspca_dev->streaming)
1847                 return gspca_init_transfer(gspca_dev);
1848         return 0;
1849 }
1850 EXPORT_SYMBOL(gspca_resume);
1851 #endif
1852 /* -- cam driver utility functions -- */
1853
1854 /* auto gain and exposure algorithm based on the knee algorithm described here:
1855    http://ytse.tricolour.net/docs/LowLightOptimization.html
1856
1857    Returns 0 if no changes were made, 1 if the gain and or exposure settings
1858    where changed. */
1859 int gspca_auto_gain_n_exposure(struct gspca_dev *gspca_dev, int avg_lum,
1860         int desired_avg_lum, int deadzone, int gain_knee, int exposure_knee)
1861 {
1862         int i, steps, gain, orig_gain, exposure, orig_exposure, autogain;
1863         const struct ctrl *gain_ctrl = NULL;
1864         const struct ctrl *exposure_ctrl = NULL;
1865         const struct ctrl *autogain_ctrl = NULL;
1866         int retval = 0;
1867
1868         for (i = 0; i < gspca_dev->sd_desc->nctrls; i++) {
1869                 if (gspca_dev->sd_desc->ctrls[i].qctrl.id == V4L2_CID_GAIN)
1870                         gain_ctrl = &gspca_dev->sd_desc->ctrls[i];
1871                 if (gspca_dev->sd_desc->ctrls[i].qctrl.id == V4L2_CID_EXPOSURE)
1872                         exposure_ctrl = &gspca_dev->sd_desc->ctrls[i];
1873                 if (gspca_dev->sd_desc->ctrls[i].qctrl.id == V4L2_CID_AUTOGAIN)
1874                         autogain_ctrl = &gspca_dev->sd_desc->ctrls[i];
1875         }
1876         if (!gain_ctrl || !exposure_ctrl || !autogain_ctrl) {
1877                 PDEBUG(D_ERR, "Error: gspca_auto_gain_n_exposure called "
1878                         "on cam without (auto)gain/exposure");
1879                 return 0;
1880         }
1881
1882         if (gain_ctrl->get(gspca_dev, &gain) ||
1883                         exposure_ctrl->get(gspca_dev, &exposure) ||
1884                         autogain_ctrl->get(gspca_dev, &autogain) || !autogain)
1885                 return 0;
1886
1887         orig_gain = gain;
1888         orig_exposure = exposure;
1889
1890         /* If we are of a multiple of deadzone, do multiple steps to reach the
1891            desired lumination fast (with the risc of a slight overshoot) */
1892         steps = abs(desired_avg_lum - avg_lum) / deadzone;
1893
1894         PDEBUG(D_FRAM, "autogain: lum: %d, desired: %d, steps: %d\n",
1895                 avg_lum, desired_avg_lum, steps);
1896
1897         for (i = 0; i < steps; i++) {
1898                 if (avg_lum > desired_avg_lum) {
1899                         if (gain > gain_knee)
1900                                 gain--;
1901                         else if (exposure > exposure_knee)
1902                                 exposure--;
1903                         else if (gain > gain_ctrl->qctrl.default_value)
1904                                 gain--;
1905                         else if (exposure > exposure_ctrl->qctrl.minimum)
1906                                 exposure--;
1907                         else if (gain > gain_ctrl->qctrl.minimum)
1908                                 gain--;
1909                         else
1910                                 break;
1911                 } else {
1912                         if (gain < gain_ctrl->qctrl.default_value)
1913                                 gain++;
1914                         else if (exposure < exposure_knee)
1915                                 exposure++;
1916                         else if (gain < gain_knee)
1917                                 gain++;
1918                         else if (exposure < exposure_ctrl->qctrl.maximum)
1919                                 exposure++;
1920                         else if (gain < gain_ctrl->qctrl.maximum)
1921                                 gain++;
1922                         else
1923                                 break;
1924                 }
1925         }
1926
1927         if (gain != orig_gain) {
1928                 gain_ctrl->set(gspca_dev, gain);
1929                 retval = 1;
1930         }
1931         if (exposure != orig_exposure) {
1932                 exposure_ctrl->set(gspca_dev, exposure);
1933                 retval = 1;
1934         }
1935
1936         return retval;
1937 }
1938 EXPORT_SYMBOL(gspca_auto_gain_n_exposure);
1939
1940 /* -- module insert / remove -- */
1941 static int __init gspca_init(void)
1942 {
1943         info("main v%d.%d.%d registered",
1944                 (DRIVER_VERSION_NUMBER >> 16) & 0xff,
1945                 (DRIVER_VERSION_NUMBER >> 8) & 0xff,
1946                 DRIVER_VERSION_NUMBER & 0xff);
1947         return 0;
1948 }
1949 static void __exit gspca_exit(void)
1950 {
1951         info("main deregistered");
1952 }
1953
1954 module_init(gspca_init);
1955 module_exit(gspca_exit);
1956
1957 #ifdef GSPCA_DEBUG
1958 module_param_named(debug, gspca_debug, int, 0644);
1959 MODULE_PARM_DESC(debug,
1960                 "Debug (bit) 0x01:error 0x02:probe 0x04:config"
1961                 " 0x08:stream 0x10:frame 0x20:packet 0x40:USBin 0x80:USBout"
1962                 " 0x0100: v4l2");
1963 #endif