V4L/DVB (8718): gspca: suspend/resume added.
[linux-2.6.git] / 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                 if (!gspca_dev->frozen)
118                         PDEBUG(D_ERR|D_PACK, "urb status: %d", urb->status);
119                 return;         /* disconnection ? */
120         }
121         pkt_scan = gspca_dev->sd_desc->pkt_scan;
122         for (i = 0; i < urb->number_of_packets; i++) {
123
124                 /* check the availability of the frame buffer */
125                 j = gspca_dev->fr_i;
126                 j = gspca_dev->fr_queue[j];
127                 frame = &gspca_dev->frame[j];
128                 if ((frame->v4l2_buf.flags & BUF_ALL_FLAGS)
129                                         != V4L2_BUF_FLAG_QUEUED) {
130                         gspca_dev->last_packet_type = DISCARD_PACKET;
131                         break;
132                 }
133
134                 /* check the packet status and length */
135                 len = urb->iso_frame_desc[i].actual_length;
136                 if (len == 0)
137                         continue;
138                 st = urb->iso_frame_desc[i].status;
139                 if (st) {
140                         PDEBUG(D_ERR,
141                                 "ISOC data error: [%d] len=%d, status=%d",
142                                 i, len, st);
143                         gspca_dev->last_packet_type = DISCARD_PACKET;
144                         continue;
145                 }
146
147                 /* let the packet be analyzed by the subdriver */
148                 PDEBUG(D_PACK, "packet [%d] o:%d l:%d",
149                         i, urb->iso_frame_desc[i].offset, len);
150                 data = (__u8 *) urb->transfer_buffer
151                                         + urb->iso_frame_desc[i].offset;
152                 pkt_scan(gspca_dev, frame, data, len);
153         }
154
155         /* resubmit the URB */
156         urb->status = 0;
157         st = usb_submit_urb(urb, GFP_ATOMIC);
158         if (st < 0)
159                 PDEBUG(D_ERR|D_PACK, "usb_submit_urb() ret %d", st);
160 }
161
162 /*
163  * ISOC message interrupt from the USB device
164  *
165  * Analyse each packet and call the subdriver for copy to the frame buffer.
166  */
167 static void isoc_irq(struct urb *urb
168 )
169 {
170         struct gspca_dev *gspca_dev = (struct gspca_dev *) urb->context;
171
172         PDEBUG(D_PACK, "isoc irq");
173         if (!gspca_dev->streaming)
174                 return;
175         fill_frame(gspca_dev, urb);
176 }
177
178 /*
179  * add data to the current frame
180  *
181  * This function is called by the subdrivers at interrupt level.
182  *
183  * To build a frame, these ones must add
184  *      - one FIRST_PACKET
185  *      - 0 or many INTER_PACKETs
186  *      - one LAST_PACKET
187  * DISCARD_PACKET invalidates the whole frame.
188  * On LAST_PACKET, a new frame is returned.
189  */
190 struct gspca_frame *gspca_frame_add(struct gspca_dev *gspca_dev,
191                                     int packet_type,
192                                     struct gspca_frame *frame,
193                                     const __u8 *data,
194                                     int len)
195 {
196         int i, j;
197
198         PDEBUG(D_PACK, "add t:%d l:%d", packet_type, len);
199
200         /* when start of a new frame, if the current frame buffer
201          * is not queued, discard the whole frame */
202         if (packet_type == FIRST_PACKET) {
203                 if ((frame->v4l2_buf.flags & BUF_ALL_FLAGS)
204                                                 != V4L2_BUF_FLAG_QUEUED) {
205                         gspca_dev->last_packet_type = DISCARD_PACKET;
206                         return frame;
207                 }
208                 frame->data_end = frame->data;
209                 jiffies_to_timeval(get_jiffies_64(),
210                                    &frame->v4l2_buf.timestamp);
211                 frame->v4l2_buf.sequence = ++gspca_dev->sequence;
212         } else if (gspca_dev->last_packet_type == DISCARD_PACKET) {
213                 if (packet_type == LAST_PACKET)
214                         gspca_dev->last_packet_type = packet_type;
215                 return frame;
216         }
217
218         /* append the packet to the frame buffer */
219         if (len > 0) {
220                 if (frame->data_end - frame->data + len
221                                                  > frame->v4l2_buf.length) {
222                         PDEBUG(D_ERR|D_PACK, "frame overflow %zd > %d",
223                                 frame->data_end - frame->data + len,
224                                 frame->v4l2_buf.length);
225                         packet_type = DISCARD_PACKET;
226                 } else {
227                         memcpy(frame->data_end, data, len);
228                         frame->data_end += len;
229                 }
230         }
231         gspca_dev->last_packet_type = packet_type;
232
233         /* if last packet, wake the application and advance in the queue */
234         if (packet_type == LAST_PACKET) {
235                 frame->v4l2_buf.bytesused = frame->data_end - frame->data;
236                 frame->v4l2_buf.flags &= ~V4L2_BUF_FLAG_QUEUED;
237                 frame->v4l2_buf.flags |= V4L2_BUF_FLAG_DONE;
238                 atomic_inc(&gspca_dev->nevent);
239                 wake_up_interruptible(&gspca_dev->wq);  /* event = new frame */
240                 i = (gspca_dev->fr_i + 1) % gspca_dev->nframes;
241                 gspca_dev->fr_i = i;
242                 PDEBUG(D_FRAM, "frame complete len:%d q:%d i:%d o:%d",
243                         frame->v4l2_buf.bytesused,
244                         gspca_dev->fr_q,
245                         i,
246                         gspca_dev->fr_o);
247                 j = gspca_dev->fr_queue[i];
248                 frame = &gspca_dev->frame[j];
249         }
250         return frame;
251 }
252 EXPORT_SYMBOL(gspca_frame_add);
253
254 static int gspca_is_compressed(__u32 format)
255 {
256         switch (format) {
257         case V4L2_PIX_FMT_MJPEG:
258         case V4L2_PIX_FMT_JPEG:
259         case V4L2_PIX_FMT_SPCA561:
260         case V4L2_PIX_FMT_PAC207:
261                 return 1;
262         }
263         return 0;
264 }
265
266 static void *rvmalloc(unsigned long size)
267 {
268         void *mem;
269         unsigned long adr;
270
271 /*      size = PAGE_ALIGN(size);        (already done) */
272         mem = vmalloc_32(size);
273         if (mem != NULL) {
274                 adr = (unsigned long) mem;
275                 while ((long) size > 0) {
276                         SetPageReserved(vmalloc_to_page((void *) adr));
277                         adr += PAGE_SIZE;
278                         size -= PAGE_SIZE;
279                 }
280         }
281         return mem;
282 }
283
284 static void rvfree(void *mem, long size)
285 {
286         unsigned long adr;
287
288         adr = (unsigned long) mem;
289         while (size > 0) {
290                 ClearPageReserved(vmalloc_to_page((void *) adr));
291                 adr += PAGE_SIZE;
292                 size -= PAGE_SIZE;
293         }
294         vfree(mem);
295 }
296
297 static int frame_alloc(struct gspca_dev *gspca_dev,
298                         unsigned int count)
299 {
300         struct gspca_frame *frame;
301         unsigned int frsz;
302         int i;
303
304         i = gspca_dev->curr_mode;
305         frsz = gspca_dev->cam.cam_mode[i].sizeimage;
306         PDEBUG(D_STREAM, "frame alloc frsz: %d", frsz);
307         frsz = PAGE_ALIGN(frsz);
308         gspca_dev->frsz = frsz;
309         if (count > GSPCA_MAX_FRAMES)
310                 count = GSPCA_MAX_FRAMES;
311         gspca_dev->frbuf = rvmalloc(frsz * count);
312         if (!gspca_dev->frbuf) {
313                 err("frame alloc failed");
314                 return -ENOMEM;
315         }
316         gspca_dev->nframes = count;
317         for (i = 0; i < count; i++) {
318                 frame = &gspca_dev->frame[i];
319                 frame->v4l2_buf.index = i;
320                 frame->v4l2_buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
321                 frame->v4l2_buf.flags = 0;
322                 frame->v4l2_buf.field = V4L2_FIELD_NONE;
323                 frame->v4l2_buf.length = frsz;
324                 frame->v4l2_buf.memory = gspca_dev->memory;
325                 frame->v4l2_buf.sequence = 0;
326                 frame->data = frame->data_end =
327                                         gspca_dev->frbuf + i * frsz;
328                 frame->v4l2_buf.m.offset = i * frsz;
329         }
330         gspca_dev->fr_i = gspca_dev->fr_o = gspca_dev->fr_q = 0;
331         gspca_dev->last_packet_type = DISCARD_PACKET;
332         gspca_dev->sequence = 0;
333         atomic_set(&gspca_dev->nevent, 0);
334         return 0;
335 }
336
337 static void frame_free(struct gspca_dev *gspca_dev)
338 {
339         int i;
340
341         PDEBUG(D_STREAM, "frame free");
342         if (gspca_dev->frbuf != NULL) {
343                 rvfree(gspca_dev->frbuf,
344                         gspca_dev->nframes * gspca_dev->frsz);
345                 gspca_dev->frbuf = NULL;
346                 for (i = 0; i < gspca_dev->nframes; i++)
347                         gspca_dev->frame[i].data = NULL;
348         }
349         gspca_dev->nframes = 0;
350 }
351
352 static void destroy_urbs(struct gspca_dev *gspca_dev)
353 {
354         struct urb *urb;
355         unsigned int i;
356
357         PDEBUG(D_STREAM, "kill transfer");
358         for (i = 0; i < MAX_NURBS; ++i) {
359                 urb = gspca_dev->urb[i];
360                 if (urb == NULL)
361                         break;
362
363                 gspca_dev->urb[i] = NULL;
364                 usb_kill_urb(urb);
365                 if (urb->transfer_buffer != NULL)
366                         usb_buffer_free(gspca_dev->dev,
367                                         urb->transfer_buffer_length,
368                                         urb->transfer_buffer,
369                                         urb->transfer_dma);
370                 usb_free_urb(urb);
371         }
372 }
373
374 /*
375  * search an input isochronous endpoint in an alternate setting
376  */
377 static struct usb_host_endpoint *alt_isoc(struct usb_host_interface *alt,
378                                           __u8 epaddr)
379 {
380         struct usb_host_endpoint *ep;
381         int i, attr;
382
383         epaddr |= USB_DIR_IN;
384         for (i = 0; i < alt->desc.bNumEndpoints; i++) {
385                 ep = &alt->endpoint[i];
386                 if (ep->desc.bEndpointAddress == epaddr) {
387                         attr = ep->desc.bmAttributes
388                                                 & USB_ENDPOINT_XFERTYPE_MASK;
389                         if (attr == USB_ENDPOINT_XFER_ISOC)
390                                 return ep;
391                         break;
392                 }
393         }
394         return NULL;
395 }
396
397 /*
398  * search an input isochronous endpoint
399  *
400  * The endpoint is defined by the subdriver.
401  * Use only the first isoc (some Zoran - 0x0572:0x0001 - have two such ep).
402  * This routine may be called many times when the bandwidth is too small
403  * (the bandwidth is checked on urb submit).
404  */
405 static struct usb_host_endpoint *get_isoc_ep(struct gspca_dev *gspca_dev)
406 {
407         struct usb_interface *intf;
408         struct usb_host_endpoint *ep;
409         int i, ret;
410
411         intf = usb_ifnum_to_if(gspca_dev->dev, gspca_dev->iface);
412         ep = NULL;
413         i = gspca_dev->alt;                     /* previous alt setting */
414         while (--i > 0) {                       /* alt 0 is unusable */
415                 ep = alt_isoc(&intf->altsetting[i], gspca_dev->cam.epaddr);
416                 if (ep)
417                         break;
418         }
419         if (ep == NULL) {
420                 err("no ISOC endpoint found");
421                 return NULL;
422         }
423         PDEBUG(D_STREAM, "use ISOC alt %d ep 0x%02x",
424                         i, ep->desc.bEndpointAddress);
425         ret = usb_set_interface(gspca_dev->dev, gspca_dev->iface, i);
426         if (ret < 0) {
427                 err("set interface err %d", ret);
428                 return NULL;
429         }
430         gspca_dev->alt = i;             /* memorize the current alt setting */
431         return ep;
432 }
433
434 /*
435  * create the isochronous URBs
436  */
437 static int create_urbs(struct gspca_dev *gspca_dev,
438                         struct usb_host_endpoint *ep)
439 {
440         struct urb *urb;
441         int n, nurbs, i, psize, npkt, bsize;
442
443         /* calculate the packet size and the number of packets */
444         psize = le16_to_cpu(ep->desc.wMaxPacketSize);
445
446         /* See paragraph 5.9 / table 5-11 of the usb 2.0 spec. */
447         psize = (psize & 0x07ff) * (1 + ((psize >> 11) & 3));
448         npkt = ISO_MAX_SIZE / psize;
449         if (npkt > ISO_MAX_PKT)
450                 npkt = ISO_MAX_PKT;
451         bsize = psize * npkt;
452         PDEBUG(D_STREAM,
453                 "isoc %d pkts size %d (bsize:%d)", npkt, psize, bsize);
454         nurbs = DEF_NURBS;
455         gspca_dev->nurbs = nurbs;
456         for (n = 0; n < nurbs; n++) {
457                 urb = usb_alloc_urb(npkt, GFP_KERNEL);
458                 if (!urb) {
459                         err("usb_alloc_urb failed");
460                         return -ENOMEM;
461                 }
462                 urb->transfer_buffer = usb_buffer_alloc(gspca_dev->dev,
463                                                 bsize,
464                                                 GFP_KERNEL,
465                                                 &urb->transfer_dma);
466
467                 if (urb->transfer_buffer == NULL) {
468                         usb_free_urb(urb);
469                         destroy_urbs(gspca_dev);
470                         err("usb_buffer_urb failed");
471                         return -ENOMEM;
472                 }
473                 gspca_dev->urb[n] = urb;
474                 urb->dev = gspca_dev->dev;
475                 urb->context = gspca_dev;
476                 urb->pipe = usb_rcvisocpipe(gspca_dev->dev,
477                                             ep->desc.bEndpointAddress);
478                 urb->transfer_flags = URB_ISO_ASAP
479                                         | URB_NO_TRANSFER_DMA_MAP;
480                 urb->interval = ep->desc.bInterval;
481                 urb->complete = isoc_irq;
482                 urb->number_of_packets = npkt;
483                 urb->transfer_buffer_length = bsize;
484                 for (i = 0; i < npkt; i++) {
485                         urb->iso_frame_desc[i].length = psize;
486                         urb->iso_frame_desc[i].offset = psize * i;
487                 }
488         }
489         return 0;
490 }
491
492 /*
493  * start the USB transfer
494  */
495 static int gspca_init_transfer(struct gspca_dev *gspca_dev)
496 {
497         struct usb_host_endpoint *ep;
498         int n, ret;
499
500         if (mutex_lock_interruptible(&gspca_dev->usb_lock))
501                 return -ERESTARTSYS;
502
503         /* set the higher alternate setting and
504          * loop until urb submit succeeds */
505         gspca_dev->alt = gspca_dev->nbalt;
506         for (;;) {
507                 PDEBUG(D_STREAM, "init transfer alt %d", gspca_dev->alt);
508                 ep = get_isoc_ep(gspca_dev);
509                 if (ep == NULL) {
510                         ret = -EIO;
511                         goto out;
512                 }
513                 ret = create_urbs(gspca_dev, ep);
514                 if (ret < 0)
515                         goto out;
516
517                 /* start the cam */
518                 gspca_dev->sd_desc->start(gspca_dev);
519                 gspca_dev->streaming = 1;
520                 atomic_set(&gspca_dev->nevent, 0);
521
522                 /* submit the URBs */
523                 for (n = 0; n < gspca_dev->nurbs; n++) {
524                         ret = usb_submit_urb(gspca_dev->urb[n], GFP_KERNEL);
525                         if (ret < 0) {
526                                 PDEBUG(D_ERR|D_STREAM,
527                                         "usb_submit_urb [%d] err %d", n, ret);
528                                 gspca_dev->streaming = 0;
529                                 destroy_urbs(gspca_dev);
530                                 if (ret == -ENOSPC)
531                                         break;  /* try the previous alt */
532                                 goto out;
533                         }
534                 }
535                 if (ret >= 0)
536                         break;
537         }
538 out:
539         mutex_unlock(&gspca_dev->usb_lock);
540         return ret;
541 }
542
543 static int gspca_set_alt0(struct gspca_dev *gspca_dev)
544 {
545         int ret;
546
547         ret = usb_set_interface(gspca_dev->dev, gspca_dev->iface, 0);
548         if (ret < 0)
549                 PDEBUG(D_ERR|D_STREAM, "set interface 0 err %d", ret);
550         return ret;
551 }
552
553 /* Note both the queue and the usb lock should be hold when calling this */
554 static void gspca_stream_off(struct gspca_dev *gspca_dev)
555 {
556         gspca_dev->streaming = 0;
557         atomic_set(&gspca_dev->nevent, 0);
558         if (gspca_dev->present) {
559                 gspca_dev->sd_desc->stopN(gspca_dev);
560                 destroy_urbs(gspca_dev);
561                 gspca_set_alt0(gspca_dev);
562                 gspca_dev->sd_desc->stop0(gspca_dev);
563                 PDEBUG(D_STREAM, "stream off OK");
564         }
565 }
566
567 static void gspca_set_default_mode(struct gspca_dev *gspca_dev)
568 {
569         int i;
570
571         i = gspca_dev->cam.nmodes - 1;  /* take the highest mode */
572         gspca_dev->curr_mode = i;
573         gspca_dev->width = gspca_dev->cam.cam_mode[i].width;
574         gspca_dev->height = gspca_dev->cam.cam_mode[i].height;
575         gspca_dev->pixfmt = gspca_dev->cam.cam_mode[i].pixelformat;
576 }
577
578 static int wxh_to_mode(struct gspca_dev *gspca_dev,
579                         int width, int height)
580 {
581         int i;
582
583         for (i = gspca_dev->cam.nmodes; --i > 0; ) {
584                 if (width >= gspca_dev->cam.cam_mode[i].width
585                     && height >= gspca_dev->cam.cam_mode[i].height)
586                         break;
587         }
588         return i;
589 }
590
591 /*
592  * search a mode with the right pixel format
593  */
594 static int gspca_get_mode(struct gspca_dev *gspca_dev,
595                         int mode,
596                         int pixfmt)
597 {
598         int modeU, modeD;
599
600         modeU = modeD = mode;
601         while ((modeU < gspca_dev->cam.nmodes) || modeD >= 0) {
602                 if (--modeD >= 0) {
603                         if (gspca_dev->cam.cam_mode[modeD].pixelformat
604                                                                 == pixfmt)
605                                 return modeD;
606                 }
607                 if (++modeU < gspca_dev->cam.nmodes) {
608                         if (gspca_dev->cam.cam_mode[modeU].pixelformat
609                                                                 == pixfmt)
610                                 return modeU;
611                 }
612         }
613         return -EINVAL;
614 }
615
616 static int vidioc_enum_fmt_vid_cap(struct file *file, void  *priv,
617                                 struct v4l2_fmtdesc *fmtdesc)
618 {
619         struct gspca_dev *gspca_dev = priv;
620         int i, j, index;
621         __u32 fmt_tb[8];
622
623         /* give an index to each format */
624         index = 0;
625         j = 0;
626         for (i = gspca_dev->cam.nmodes; --i >= 0; ) {
627                 fmt_tb[index] = gspca_dev->cam.cam_mode[i].pixelformat;
628                 j = 0;
629                 for (;;) {
630                         if (fmt_tb[j] == fmt_tb[index])
631                                 break;
632                         j++;
633                 }
634                 if (j == index) {
635                         if (fmtdesc->index == index)
636                                 break;          /* new format */
637                         index++;
638                         if (index >= sizeof fmt_tb / sizeof fmt_tb[0])
639                                 return -EINVAL;
640                 }
641         }
642         if (i < 0)
643                 return -EINVAL;         /* no more format */
644
645         fmtdesc->pixelformat = fmt_tb[index];
646         if (gspca_is_compressed(fmt_tb[index]))
647                 fmtdesc->flags = V4L2_FMT_FLAG_COMPRESSED;
648         fmtdesc->type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
649         fmtdesc->description[0] = fmtdesc->pixelformat & 0xff;
650         fmtdesc->description[1] = (fmtdesc->pixelformat >> 8) & 0xff;
651         fmtdesc->description[2] = (fmtdesc->pixelformat >> 16) & 0xff;
652         fmtdesc->description[3] = fmtdesc->pixelformat >> 24;
653         fmtdesc->description[4] = '\0';
654         return 0;
655 }
656
657 static int vidioc_g_fmt_vid_cap(struct file *file, void *priv,
658                             struct v4l2_format *fmt)
659 {
660         struct gspca_dev *gspca_dev = priv;
661         int mode;
662
663         if (fmt->type != V4L2_BUF_TYPE_VIDEO_CAPTURE)
664                 return -EINVAL;
665         mode = gspca_dev->curr_mode;
666         memcpy(&fmt->fmt.pix, &gspca_dev->cam.cam_mode[mode],
667                 sizeof fmt->fmt.pix);
668         return 0;
669 }
670
671 static int try_fmt_vid_cap(struct gspca_dev *gspca_dev,
672                         struct v4l2_format *fmt)
673 {
674         int w, h, mode, mode2;
675
676         if (fmt->type != V4L2_BUF_TYPE_VIDEO_CAPTURE)
677                 return -EINVAL;
678         w = fmt->fmt.pix.width;
679         h = fmt->fmt.pix.height;
680
681 #ifdef GSPCA_DEBUG
682         if (gspca_debug & D_CONF)
683                 PDEBUG_MODE("try fmt cap", fmt->fmt.pix.pixelformat, w, h);
684 #endif
685         /* search the closest mode for width and height */
686         mode = wxh_to_mode(gspca_dev, w, h);
687
688         /* OK if right palette */
689         if (gspca_dev->cam.cam_mode[mode].pixelformat
690                                                 != fmt->fmt.pix.pixelformat) {
691
692                 /* else, search the closest mode with the same pixel format */
693                 mode2 = gspca_get_mode(gspca_dev, mode,
694                                         fmt->fmt.pix.pixelformat);
695                 if (mode2 >= 0)
696                         mode = mode2;
697 /*              else
698                         ;                * no chance, return this mode */
699         }
700         memcpy(&fmt->fmt.pix, &gspca_dev->cam.cam_mode[mode],
701                 sizeof fmt->fmt.pix);
702         return mode;                    /* used when s_fmt */
703 }
704
705 static int vidioc_try_fmt_vid_cap(struct file *file,
706                               void *priv,
707                               struct v4l2_format *fmt)
708 {
709         struct gspca_dev *gspca_dev = priv;
710         int ret;
711
712         ret = try_fmt_vid_cap(gspca_dev, fmt);
713         if (ret < 0)
714                 return ret;
715         return 0;
716 }
717
718 static int vidioc_s_fmt_vid_cap(struct file *file, void *priv,
719                             struct v4l2_format *fmt)
720 {
721         struct gspca_dev *gspca_dev = priv;
722         int ret;
723
724         if (mutex_lock_interruptible(&gspca_dev->queue_lock))
725                 return -ERESTARTSYS;
726
727         ret = try_fmt_vid_cap(gspca_dev, fmt);
728         if (ret < 0)
729                 goto out;
730
731         if (gspca_dev->nframes != 0
732             && fmt->fmt.pix.sizeimage > gspca_dev->frsz) {
733                 ret = -EINVAL;
734                 goto out;
735         }
736
737         if (ret == gspca_dev->curr_mode) {
738                 ret = 0;
739                 goto out;                       /* same mode */
740         }
741
742         if (gspca_dev->streaming) {
743                 ret = -EBUSY;
744                 goto out;
745         }
746         gspca_dev->width = fmt->fmt.pix.width;
747         gspca_dev->height = fmt->fmt.pix.height;
748         gspca_dev->pixfmt = fmt->fmt.pix.pixelformat;
749         gspca_dev->curr_mode = ret;
750
751         ret = 0;
752 out:
753         mutex_unlock(&gspca_dev->queue_lock);
754         return ret;
755 }
756
757 static int dev_open(struct inode *inode, struct file *file)
758 {
759         struct gspca_dev *gspca_dev;
760         int ret;
761
762         PDEBUG(D_STREAM, "%s open", current->comm);
763         gspca_dev = (struct gspca_dev *) video_devdata(file);
764         if (mutex_lock_interruptible(&gspca_dev->queue_lock))
765                 return -ERESTARTSYS;
766         if (!gspca_dev->present) {
767                 ret = -ENODEV;
768                 goto out;
769         }
770
771         /* if not done yet, initialize the sensor */
772         if (gspca_dev->users == 0) {
773                 if (mutex_lock_interruptible(&gspca_dev->usb_lock)) {
774                         ret = -ERESTARTSYS;
775                         goto out;
776                 }
777                 ret = gspca_dev->sd_desc->open(gspca_dev);
778                 mutex_unlock(&gspca_dev->usb_lock);
779                 if (ret != 0) {
780                         PDEBUG(D_ERR|D_CONF, "init device failed %d", ret);
781                         goto out;
782                 }
783         } else if (gspca_dev->users > 4) {      /* (arbitrary value) */
784                 ret = -EBUSY;
785                 goto out;
786         }
787         gspca_dev->users++;
788         file->private_data = gspca_dev;
789 #ifdef GSPCA_DEBUG
790         /* activate the v4l2 debug */
791         if (gspca_debug & D_V4L2)
792                 gspca_dev->vdev.debug |= 3;
793         else
794                 gspca_dev->vdev.debug &= ~3;
795 #endif
796 out:
797         mutex_unlock(&gspca_dev->queue_lock);
798         if (ret != 0)
799                 PDEBUG(D_ERR|D_STREAM, "open failed err %d", ret);
800         else
801                 PDEBUG(D_STREAM, "open done");
802         return ret;
803 }
804
805 static int dev_close(struct inode *inode, struct file *file)
806 {
807         struct gspca_dev *gspca_dev = file->private_data;
808
809         PDEBUG(D_STREAM, "%s close", current->comm);
810         if (mutex_lock_interruptible(&gspca_dev->queue_lock))
811                 return -ERESTARTSYS;
812         gspca_dev->users--;
813
814         /* if the file did the capture, free the streaming resources */
815         if (gspca_dev->capt_file == file) {
816                 mutex_lock(&gspca_dev->usb_lock);
817                 if (gspca_dev->streaming)
818                         gspca_stream_off(gspca_dev);
819                 gspca_dev->sd_desc->close(gspca_dev);
820                 mutex_unlock(&gspca_dev->usb_lock);
821                 frame_free(gspca_dev);
822                 gspca_dev->capt_file = NULL;
823                 gspca_dev->memory = GSPCA_MEMORY_NO;
824         }
825         file->private_data = NULL;
826         mutex_unlock(&gspca_dev->queue_lock);
827         PDEBUG(D_STREAM, "close done");
828         return 0;
829 }
830
831 static int vidioc_querycap(struct file *file, void  *priv,
832                            struct v4l2_capability *cap)
833 {
834         struct gspca_dev *gspca_dev = priv;
835
836         memset(cap, 0, sizeof *cap);
837         strncpy(cap->driver, gspca_dev->sd_desc->name, sizeof cap->driver);
838 /*      strncpy(cap->card, gspca_dev->cam.dev_name, sizeof cap->card); */
839         if (gspca_dev->dev->product != NULL) {
840                 strncpy(cap->card, gspca_dev->dev->product,
841                         sizeof cap->card);
842         } else {
843                 snprintf(cap->card, sizeof cap->card,
844                         "USB Camera (%04x:%04x)",
845                         le16_to_cpu(gspca_dev->dev->descriptor.idVendor),
846                         le16_to_cpu(gspca_dev->dev->descriptor.idProduct));
847         }
848         strncpy(cap->bus_info, gspca_dev->dev->bus->bus_name,
849                 sizeof cap->bus_info);
850         cap->version = DRIVER_VERSION_NUMBER;
851         cap->capabilities = V4L2_CAP_VIDEO_CAPTURE
852                           | V4L2_CAP_STREAMING
853                           | V4L2_CAP_READWRITE;
854         return 0;
855 }
856
857 /* the use of V4L2_CTRL_FLAG_NEXT_CTRL asks for the controls to be sorted */
858 static int vidioc_queryctrl(struct file *file, void *priv,
859                            struct v4l2_queryctrl *q_ctrl)
860 {
861         struct gspca_dev *gspca_dev = priv;
862         int i;
863         u32 id;
864
865         id = q_ctrl->id;
866         if (id & V4L2_CTRL_FLAG_NEXT_CTRL) {
867                 id &= V4L2_CTRL_ID_MASK;
868                 id++;
869                 for (i = 0; i < gspca_dev->sd_desc->nctrls; i++) {
870                         if (id >= gspca_dev->sd_desc->ctrls[i].qctrl.id) {
871                                 memcpy(q_ctrl,
872                                         &gspca_dev->sd_desc->ctrls[i].qctrl,
873                                         sizeof *q_ctrl);
874                                 return 0;
875                         }
876                 }
877                 return -EINVAL;
878         }
879         for (i = 0; i < gspca_dev->sd_desc->nctrls; i++) {
880                 if (id == gspca_dev->sd_desc->ctrls[i].qctrl.id) {
881                         memcpy(q_ctrl,
882                                 &gspca_dev->sd_desc->ctrls[i].qctrl,
883                                 sizeof *q_ctrl);
884                         return 0;
885                 }
886         }
887         if (id >= V4L2_CID_BASE
888             && id <= V4L2_CID_LASTP1) {
889                 q_ctrl->flags |= V4L2_CTRL_FLAG_DISABLED;
890                 return 0;
891         }
892         return -EINVAL;
893 }
894
895 static int vidioc_s_ctrl(struct file *file, void *priv,
896                          struct v4l2_control *ctrl)
897 {
898         struct gspca_dev *gspca_dev = priv;
899         const struct ctrl *ctrls;
900         int i, ret;
901
902         for (i = 0, ctrls = gspca_dev->sd_desc->ctrls;
903              i < gspca_dev->sd_desc->nctrls;
904              i++, ctrls++) {
905                 if (ctrl->id != ctrls->qctrl.id)
906                         continue;
907                 if (ctrl->value < ctrls->qctrl.minimum
908                     || ctrl->value > ctrls->qctrl.maximum)
909                         return -ERANGE;
910                 PDEBUG(D_CONF, "set ctrl [%08x] = %d", ctrl->id, ctrl->value);
911                 if (mutex_lock_interruptible(&gspca_dev->usb_lock))
912                         return -ERESTARTSYS;
913                 ret = ctrls->set(gspca_dev, ctrl->value);
914                 mutex_unlock(&gspca_dev->usb_lock);
915                 return ret;
916         }
917         return -EINVAL;
918 }
919
920 static int vidioc_g_ctrl(struct file *file, void *priv,
921                          struct v4l2_control *ctrl)
922 {
923         struct gspca_dev *gspca_dev = priv;
924
925         const struct ctrl *ctrls;
926         int i, ret;
927
928         for (i = 0, ctrls = gspca_dev->sd_desc->ctrls;
929              i < gspca_dev->sd_desc->nctrls;
930              i++, ctrls++) {
931                 if (ctrl->id != ctrls->qctrl.id)
932                         continue;
933                 if (mutex_lock_interruptible(&gspca_dev->usb_lock))
934                         return -ERESTARTSYS;
935                 ret = ctrls->get(gspca_dev, &ctrl->value);
936                 mutex_unlock(&gspca_dev->usb_lock);
937                 return ret;
938         }
939         return -EINVAL;
940 }
941
942 static int vidioc_querymenu(struct file *file, void *priv,
943                             struct v4l2_querymenu *qmenu)
944 {
945         struct gspca_dev *gspca_dev = priv;
946
947         if (!gspca_dev->sd_desc->querymenu)
948                 return -EINVAL;
949         return gspca_dev->sd_desc->querymenu(gspca_dev, qmenu);
950 }
951
952 static int vidioc_enum_input(struct file *file, void *priv,
953                                 struct v4l2_input *input)
954 {
955         struct gspca_dev *gspca_dev = priv;
956
957         if (input->index != 0)
958                 return -EINVAL;
959         memset(input, 0, sizeof *input);
960         input->type = V4L2_INPUT_TYPE_CAMERA;
961         strncpy(input->name, gspca_dev->sd_desc->name,
962                 sizeof input->name);
963         return 0;
964 }
965
966 static int vidioc_g_input(struct file *file, void *priv, unsigned int *i)
967 {
968         *i = 0;
969         return 0;
970 }
971
972 static int vidioc_s_input(struct file *file, void *priv, unsigned int i)
973 {
974         if (i > 0)
975                 return -EINVAL;
976         return (0);
977 }
978
979 static int vidioc_reqbufs(struct file *file, void *priv,
980                           struct v4l2_requestbuffers *rb)
981 {
982         struct gspca_dev *gspca_dev = priv;
983         int i, ret = 0;
984
985         if (rb->type != V4L2_BUF_TYPE_VIDEO_CAPTURE)
986                 return -EINVAL;
987         switch (rb->memory) {
988         case GSPCA_MEMORY_READ:                 /* (internal call) */
989         case V4L2_MEMORY_MMAP:
990         case V4L2_MEMORY_USERPTR:
991                 break;
992         default:
993                 return -EINVAL;
994         }
995         if (mutex_lock_interruptible(&gspca_dev->queue_lock))
996                 return -ERESTARTSYS;
997
998         if (gspca_dev->memory != GSPCA_MEMORY_NO
999             && gspca_dev->memory != rb->memory) {
1000                 ret = -EBUSY;
1001                 goto out;
1002         }
1003
1004         /* only one file may do the capture */
1005         if (gspca_dev->capt_file != NULL
1006             && gspca_dev->capt_file != file) {
1007                 ret = -EBUSY;
1008                 goto out;
1009         }
1010
1011         /* if allocated, the buffers must not be mapped */
1012         for (i = 0; i < gspca_dev->nframes; i++) {
1013                 if (gspca_dev->frame[i].vma_use_count) {
1014                         ret = -EBUSY;
1015                         goto out;
1016                 }
1017         }
1018
1019         /* stop streaming */
1020         if (gspca_dev->streaming) {
1021                 mutex_lock(&gspca_dev->usb_lock);
1022                 gspca_stream_off(gspca_dev);
1023                 mutex_unlock(&gspca_dev->usb_lock);
1024         }
1025
1026         /* free the previous allocated buffers, if any */
1027         if (gspca_dev->nframes != 0) {
1028                 frame_free(gspca_dev);
1029                 gspca_dev->capt_file = NULL;
1030         }
1031         if (rb->count == 0)                     /* unrequest */
1032                 goto out;
1033         gspca_dev->memory = rb->memory;
1034         ret = frame_alloc(gspca_dev, rb->count);
1035         if (ret == 0) {
1036                 rb->count = gspca_dev->nframes;
1037                 gspca_dev->capt_file = file;
1038         }
1039 out:
1040         mutex_unlock(&gspca_dev->queue_lock);
1041         PDEBUG(D_STREAM, "reqbufs st:%d c:%d", ret, rb->count);
1042         return ret;
1043 }
1044
1045 static int vidioc_querybuf(struct file *file, void *priv,
1046                            struct v4l2_buffer *v4l2_buf)
1047 {
1048         struct gspca_dev *gspca_dev = priv;
1049         struct gspca_frame *frame;
1050
1051         if (v4l2_buf->type != V4L2_BUF_TYPE_VIDEO_CAPTURE
1052             || v4l2_buf->index < 0
1053             || v4l2_buf->index >= gspca_dev->nframes)
1054                 return -EINVAL;
1055
1056         frame = &gspca_dev->frame[v4l2_buf->index];
1057         memcpy(v4l2_buf, &frame->v4l2_buf, sizeof *v4l2_buf);
1058         return 0;
1059 }
1060
1061 static int vidioc_streamon(struct file *file, void *priv,
1062                            enum v4l2_buf_type buf_type)
1063 {
1064         struct gspca_dev *gspca_dev = priv;
1065         int ret;
1066
1067         if (buf_type != V4L2_BUF_TYPE_VIDEO_CAPTURE)
1068                 return -EINVAL;
1069         if (mutex_lock_interruptible(&gspca_dev->queue_lock))
1070                 return -ERESTARTSYS;
1071         if (!gspca_dev->present) {
1072                 ret = -ENODEV;
1073                 goto out;
1074         }
1075         if (gspca_dev->nframes == 0) {
1076                 ret = -EINVAL;
1077                 goto out;
1078         }
1079         if (!gspca_dev->streaming) {
1080                 ret = gspca_init_transfer(gspca_dev);
1081                 if (ret < 0)
1082                         goto out;
1083         }
1084 #ifdef GSPCA_DEBUG
1085         if (gspca_debug & D_STREAM) {
1086                 PDEBUG_MODE("stream on OK",
1087                         gspca_dev->pixfmt,
1088                         gspca_dev->width,
1089                         gspca_dev->height);
1090         }
1091 #endif
1092         ret = 0;
1093 out:
1094         mutex_unlock(&gspca_dev->queue_lock);
1095         return ret;
1096 }
1097
1098 static int vidioc_streamoff(struct file *file, void *priv,
1099                                 enum v4l2_buf_type buf_type)
1100 {
1101         struct gspca_dev *gspca_dev = priv;
1102         int i, ret;
1103
1104         if (buf_type != V4L2_BUF_TYPE_VIDEO_CAPTURE)
1105                 return -EINVAL;
1106         if (!gspca_dev->streaming)
1107                 return 0;
1108         if (mutex_lock_interruptible(&gspca_dev->queue_lock))
1109                 return -ERESTARTSYS;
1110
1111         /* stop streaming */
1112         if (mutex_lock_interruptible(&gspca_dev->usb_lock)) {
1113                 ret = -ERESTARTSYS;
1114                 goto out;
1115         }
1116         gspca_stream_off(gspca_dev);
1117         mutex_unlock(&gspca_dev->usb_lock);
1118
1119         /* empty the application queues */
1120         for (i = 0; i < gspca_dev->nframes; i++)
1121                 gspca_dev->frame[i].v4l2_buf.flags &= ~BUF_ALL_FLAGS;
1122         gspca_dev->fr_i = gspca_dev->fr_o = gspca_dev->fr_q = 0;
1123         gspca_dev->last_packet_type = DISCARD_PACKET;
1124         gspca_dev->sequence = 0;
1125         atomic_set(&gspca_dev->nevent, 0);
1126         ret = 0;
1127 out:
1128         mutex_unlock(&gspca_dev->queue_lock);
1129         return ret;
1130 }
1131
1132 static int vidioc_g_jpegcomp(struct file *file, void *priv,
1133                         struct v4l2_jpegcompression *jpegcomp)
1134 {
1135         struct gspca_dev *gspca_dev = priv;
1136         int ret;
1137
1138         if (!gspca_dev->sd_desc->get_jcomp)
1139                 return -EINVAL;
1140         if (mutex_lock_interruptible(&gspca_dev->usb_lock))
1141                 return -ERESTARTSYS;
1142         ret = gspca_dev->sd_desc->get_jcomp(gspca_dev, jpegcomp);
1143         mutex_unlock(&gspca_dev->usb_lock);
1144         return ret;
1145 }
1146
1147 static int vidioc_s_jpegcomp(struct file *file, void *priv,
1148                         struct v4l2_jpegcompression *jpegcomp)
1149 {
1150         struct gspca_dev *gspca_dev = priv;
1151         int ret;
1152
1153         if (mutex_lock_interruptible(&gspca_dev->usb_lock))
1154                 return -ERESTARTSYS;
1155         if (!gspca_dev->sd_desc->set_jcomp)
1156                 return -EINVAL;
1157         ret = gspca_dev->sd_desc->set_jcomp(gspca_dev, jpegcomp);
1158         mutex_unlock(&gspca_dev->usb_lock);
1159         return ret;
1160 }
1161
1162 static int vidioc_g_parm(struct file *filp, void *priv,
1163                         struct v4l2_streamparm *parm)
1164 {
1165         struct gspca_dev *gspca_dev = priv;
1166
1167         memset(parm, 0, sizeof *parm);
1168         parm->type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
1169         parm->parm.capture.readbuffers = gspca_dev->nbufread;
1170         return 0;
1171 }
1172
1173 static int vidioc_s_parm(struct file *filp, void *priv,
1174                         struct v4l2_streamparm *parm)
1175 {
1176         struct gspca_dev *gspca_dev = priv;
1177         int n;
1178
1179         n = parm->parm.capture.readbuffers;
1180         if (n == 0 || n > GSPCA_MAX_FRAMES)
1181                 parm->parm.capture.readbuffers = gspca_dev->nbufread;
1182         else
1183                 gspca_dev->nbufread = n;
1184         return 0;
1185 }
1186
1187 static int vidioc_s_std(struct file *filp, void *priv,
1188                         v4l2_std_id *parm)
1189 {
1190         return 0;
1191 }
1192
1193 #ifdef CONFIG_VIDEO_V4L1_COMPAT
1194 static int vidiocgmbuf(struct file *file, void *priv,
1195                         struct video_mbuf *mbuf)
1196 {
1197         struct gspca_dev *gspca_dev = file->private_data;
1198         int i;
1199
1200         PDEBUG(D_STREAM, "cgmbuf");
1201         if (gspca_dev->nframes == 0) {
1202                 int ret;
1203
1204                 {
1205                         struct v4l2_format fmt;
1206
1207                         memset(&fmt, 0, sizeof fmt);
1208                         fmt.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
1209                         i = gspca_dev->cam.nmodes - 1;  /* highest mode */
1210                         fmt.fmt.pix.width = gspca_dev->cam.cam_mode[i].width;
1211                         fmt.fmt.pix.height = gspca_dev->cam.cam_mode[i].height;
1212                         fmt.fmt.pix.pixelformat = V4L2_PIX_FMT_BGR24;
1213                         ret = vidioc_s_fmt_vid_cap(file, priv, &fmt);
1214                         if (ret != 0)
1215                                 return ret;
1216                 }
1217                 {
1218                         struct v4l2_requestbuffers rb;
1219
1220                         memset(&rb, 0, sizeof rb);
1221                         rb.count = 4;
1222                         rb.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
1223                         rb.memory = V4L2_MEMORY_MMAP;
1224                         ret = vidioc_reqbufs(file, priv, &rb);
1225                         if (ret != 0)
1226                                 return ret;
1227                 }
1228         }
1229         mbuf->frames = gspca_dev->nframes;
1230         mbuf->size = gspca_dev->frsz * gspca_dev->nframes;
1231         for (i = 0; i < mbuf->frames; i++)
1232                 mbuf->offsets[i] = gspca_dev->frame[i].v4l2_buf.m.offset;
1233         return 0;
1234 }
1235 #endif
1236
1237 static int dev_mmap(struct file *file, struct vm_area_struct *vma)
1238 {
1239         struct gspca_dev *gspca_dev = file->private_data;
1240         struct gspca_frame *frame;
1241         struct page *page;
1242         unsigned long addr, start, size;
1243         int i, ret;
1244
1245         start = vma->vm_start;
1246         size = vma->vm_end - vma->vm_start;
1247         PDEBUG(D_STREAM, "mmap start:%08x size:%d", (int) start, (int) size);
1248
1249         if (mutex_lock_interruptible(&gspca_dev->queue_lock))
1250                 return -ERESTARTSYS;
1251         if (!gspca_dev->present) {
1252                 ret = -ENODEV;
1253                 goto out;
1254         }
1255         if (gspca_dev->capt_file != file) {
1256                 ret = -EINVAL;
1257                 goto out;
1258         }
1259
1260         frame = NULL;
1261         for (i = 0; i < gspca_dev->nframes; ++i) {
1262                 if (gspca_dev->frame[i].v4l2_buf.memory != V4L2_MEMORY_MMAP) {
1263                         PDEBUG(D_STREAM, "mmap bad memory type");
1264                         break;
1265                 }
1266                 if ((gspca_dev->frame[i].v4l2_buf.m.offset >> PAGE_SHIFT)
1267                                                 == vma->vm_pgoff) {
1268                         frame = &gspca_dev->frame[i];
1269                         break;
1270                 }
1271         }
1272         if (frame == NULL) {
1273                 PDEBUG(D_STREAM, "mmap no frame buffer found");
1274                 ret = -EINVAL;
1275                 goto out;
1276         }
1277 #ifdef CONFIG_VIDEO_V4L1_COMPAT
1278         /* v4l1 maps all the buffers */
1279         if (i != 0
1280             || size != frame->v4l2_buf.length * gspca_dev->nframes)
1281 #endif
1282             if (size != frame->v4l2_buf.length) {
1283                 PDEBUG(D_STREAM, "mmap bad size");
1284                 ret = -EINVAL;
1285                 goto out;
1286         }
1287
1288         /*
1289          * - VM_IO marks the area as being a mmaped region for I/O to a
1290          *   device. It also prevents the region from being core dumped.
1291          */
1292         vma->vm_flags |= VM_IO;
1293
1294         addr = (unsigned long) frame->data;
1295         while (size > 0) {
1296                 page = vmalloc_to_page((void *) addr);
1297                 ret = vm_insert_page(vma, start, page);
1298                 if (ret < 0)
1299                         goto out;
1300                 start += PAGE_SIZE;
1301                 addr += PAGE_SIZE;
1302                 size -= PAGE_SIZE;
1303         }
1304
1305         vma->vm_ops = &gspca_vm_ops;
1306         vma->vm_private_data = frame;
1307         gspca_vm_open(vma);
1308         ret = 0;
1309 out:
1310         mutex_unlock(&gspca_dev->queue_lock);
1311         return ret;
1312 }
1313
1314 /*
1315  * wait for a video frame
1316  *
1317  * If a frame is ready, its index is returned.
1318  */
1319 static int frame_wait(struct gspca_dev *gspca_dev,
1320                         int nonblock_ing)
1321 {
1322         struct gspca_frame *frame;
1323         int i, j, ret;
1324
1325         /* check if a frame is ready */
1326         i = gspca_dev->fr_o;
1327         j = gspca_dev->fr_queue[i];
1328         frame = &gspca_dev->frame[j];
1329         if (frame->v4l2_buf.flags & V4L2_BUF_FLAG_DONE) {
1330                 atomic_dec(&gspca_dev->nevent);
1331                 goto ok;
1332         }
1333         if (nonblock_ing)                       /* no frame yet */
1334                 return -EAGAIN;
1335
1336         /* wait till a frame is ready */
1337         for (;;) {
1338                 ret = wait_event_interruptible_timeout(gspca_dev->wq,
1339                                         atomic_read(&gspca_dev->nevent) > 0,
1340                                         msecs_to_jiffies(3000));
1341                 if (ret <= 0) {
1342                         if (ret < 0)
1343                                 return ret;     /* interrupt */
1344                         return -EIO;            /* timeout */
1345                 }
1346                 atomic_dec(&gspca_dev->nevent);
1347                 if (!gspca_dev->streaming || !gspca_dev->present)
1348                         return -EIO;
1349                 i = gspca_dev->fr_o;
1350                 j = gspca_dev->fr_queue[i];
1351                 frame = &gspca_dev->frame[j];
1352                 if (frame->v4l2_buf.flags & V4L2_BUF_FLAG_DONE)
1353                         break;
1354         }
1355 ok:
1356         gspca_dev->fr_o = (i + 1) % gspca_dev->nframes;
1357         PDEBUG(D_FRAM, "frame wait q:%d i:%d o:%d",
1358                 gspca_dev->fr_q,
1359                 gspca_dev->fr_i,
1360                 gspca_dev->fr_o);
1361
1362         if (gspca_dev->sd_desc->dq_callback) {
1363                 mutex_lock(&gspca_dev->usb_lock);
1364                 gspca_dev->sd_desc->dq_callback(gspca_dev);
1365                 mutex_unlock(&gspca_dev->usb_lock);
1366         }
1367         return j;
1368 }
1369
1370 /*
1371  * dequeue a video buffer
1372  *
1373  * If nonblock_ing is false, block until a buffer is available.
1374  */
1375 static int vidioc_dqbuf(struct file *file, void *priv,
1376                         struct v4l2_buffer *v4l2_buf)
1377 {
1378         struct gspca_dev *gspca_dev = priv;
1379         struct gspca_frame *frame;
1380         int i, ret;
1381
1382         PDEBUG(D_FRAM, "dqbuf");
1383         if (v4l2_buf->type != V4L2_BUF_TYPE_VIDEO_CAPTURE)
1384                 return -EINVAL;
1385         if (v4l2_buf->memory != gspca_dev->memory)
1386                 return -EINVAL;
1387
1388         /* if not streaming, be sure the application will not loop forever */
1389         if (!(file->f_flags & O_NONBLOCK)
1390             && !gspca_dev->streaming && gspca_dev->users == 1)
1391                 return -EINVAL;
1392
1393         /* only the capturing file may dequeue */
1394         if (gspca_dev->capt_file != file)
1395                 return -EINVAL;
1396
1397         /* only one dequeue / read at a time */
1398         if (mutex_lock_interruptible(&gspca_dev->read_lock))
1399                 return -ERESTARTSYS;
1400
1401         ret = frame_wait(gspca_dev, file->f_flags & O_NONBLOCK);
1402         if (ret < 0)
1403                 goto out;
1404         i = ret;                                /* frame index */
1405         frame = &gspca_dev->frame[i];
1406         if (gspca_dev->memory == V4L2_MEMORY_USERPTR) {
1407                 if (copy_to_user((__u8 *) frame->v4l2_buf.m.userptr,
1408                                  frame->data,
1409                                  frame->v4l2_buf.bytesused)) {
1410                         PDEBUG(D_ERR|D_STREAM,
1411                                 "dqbuf cp to user failed");
1412                         ret = -EFAULT;
1413                         goto out;
1414                 }
1415         }
1416         frame->v4l2_buf.flags &= ~V4L2_BUF_FLAG_DONE;
1417         memcpy(v4l2_buf, &frame->v4l2_buf, sizeof *v4l2_buf);
1418         PDEBUG(D_FRAM, "dqbuf %d", i);
1419         ret = 0;
1420 out:
1421         mutex_unlock(&gspca_dev->read_lock);
1422         return ret;
1423 }
1424
1425 /*
1426  * queue a video buffer
1427  *
1428  * Attempting to queue a buffer that has already been
1429  * queued will return -EINVAL.
1430  */
1431 static int vidioc_qbuf(struct file *file, void *priv,
1432                         struct v4l2_buffer *v4l2_buf)
1433 {
1434         struct gspca_dev *gspca_dev = priv;
1435         struct gspca_frame *frame;
1436         int i, index, ret;
1437
1438         PDEBUG(D_FRAM, "qbuf %d", v4l2_buf->index);
1439         if (v4l2_buf->type != V4L2_BUF_TYPE_VIDEO_CAPTURE)
1440                 return -EINVAL;
1441
1442         if (mutex_lock_interruptible(&gspca_dev->queue_lock))
1443                 return -ERESTARTSYS;
1444
1445         index = v4l2_buf->index;
1446         if ((unsigned) index >= gspca_dev->nframes) {
1447                 PDEBUG(D_FRAM,
1448                         "qbuf idx %d >= %d", index, gspca_dev->nframes);
1449                 ret = -EINVAL;
1450                 goto out;
1451         }
1452         if (v4l2_buf->memory != gspca_dev->memory) {
1453                 PDEBUG(D_FRAM, "qbuf bad memory type");
1454                 ret = -EINVAL;
1455                 goto out;
1456         }
1457
1458         frame = &gspca_dev->frame[index];
1459         if (frame->v4l2_buf.flags & BUF_ALL_FLAGS) {
1460                 PDEBUG(D_FRAM, "qbuf bad state");
1461                 ret = -EINVAL;
1462                 goto out;
1463         }
1464
1465         frame->v4l2_buf.flags |= V4L2_BUF_FLAG_QUEUED;
1466 /*      frame->v4l2_buf.flags &= ~V4L2_BUF_FLAG_DONE; */
1467
1468         if (frame->v4l2_buf.memory == V4L2_MEMORY_USERPTR) {
1469                 frame->v4l2_buf.m.userptr = v4l2_buf->m.userptr;
1470                 frame->v4l2_buf.length = v4l2_buf->length;
1471         }
1472
1473         /* put the buffer in the 'queued' queue */
1474         i = gspca_dev->fr_q;
1475         gspca_dev->fr_queue[i] = index;
1476         gspca_dev->fr_q = (i + 1) % gspca_dev->nframes;
1477         PDEBUG(D_FRAM, "qbuf q:%d i:%d o:%d",
1478                 gspca_dev->fr_q,
1479                 gspca_dev->fr_i,
1480                 gspca_dev->fr_o);
1481
1482         v4l2_buf->flags |= V4L2_BUF_FLAG_QUEUED;
1483         v4l2_buf->flags &= ~V4L2_BUF_FLAG_DONE;
1484         ret = 0;
1485 out:
1486         mutex_unlock(&gspca_dev->queue_lock);
1487         return ret;
1488 }
1489
1490 /*
1491  * allocate the resources for read()
1492  */
1493 static int read_alloc(struct gspca_dev *gspca_dev,
1494                         struct file *file)
1495 {
1496         struct v4l2_buffer v4l2_buf;
1497         int i, ret;
1498
1499         PDEBUG(D_STREAM, "read alloc");
1500         if (gspca_dev->nframes == 0) {
1501                 struct v4l2_requestbuffers rb;
1502
1503                 memset(&rb, 0, sizeof rb);
1504                 rb.count = gspca_dev->nbufread;
1505                 rb.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
1506                 rb.memory = GSPCA_MEMORY_READ;
1507                 ret = vidioc_reqbufs(file, gspca_dev, &rb);
1508                 if (ret != 0) {
1509                         PDEBUG(D_STREAM, "read reqbuf err %d", ret);
1510                         return ret;
1511                 }
1512                 memset(&v4l2_buf, 0, sizeof v4l2_buf);
1513                 v4l2_buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
1514                 v4l2_buf.memory = GSPCA_MEMORY_READ;
1515                 for (i = 0; i < gspca_dev->nbufread; i++) {
1516                         v4l2_buf.index = i;
1517                         ret = vidioc_qbuf(file, gspca_dev, &v4l2_buf);
1518                         if (ret != 0) {
1519                                 PDEBUG(D_STREAM, "read qbuf err: %d", ret);
1520                                 return ret;
1521                         }
1522                 }
1523                 gspca_dev->memory = GSPCA_MEMORY_READ;
1524         }
1525
1526         /* start streaming */
1527         ret = vidioc_streamon(file, gspca_dev, V4L2_BUF_TYPE_VIDEO_CAPTURE);
1528         if (ret != 0)
1529                 PDEBUG(D_STREAM, "read streamon err %d", ret);
1530         return ret;
1531 }
1532
1533 static unsigned int dev_poll(struct file *file, poll_table *wait)
1534 {
1535         struct gspca_dev *gspca_dev = file->private_data;
1536         int i, ret;
1537
1538         PDEBUG(D_FRAM, "poll");
1539
1540         poll_wait(file, &gspca_dev->wq, wait);
1541         if (!gspca_dev->present)
1542                 return POLLERR;
1543
1544         /* if reqbufs is not done, the user would use read() */
1545         if (gspca_dev->nframes == 0) {
1546                 if (gspca_dev->memory != GSPCA_MEMORY_NO)
1547                         return POLLERR;         /* not the 1st time */
1548                 ret = read_alloc(gspca_dev, file);
1549                 if (ret != 0)
1550                         return POLLERR;
1551         }
1552
1553         if (mutex_lock_interruptible(&gspca_dev->queue_lock) != 0)
1554                 return POLLERR;
1555         if (!gspca_dev->present) {
1556                 ret = POLLERR;
1557                 goto out;
1558         }
1559
1560         /* check the next incoming buffer */
1561         i = gspca_dev->fr_o;
1562         i = gspca_dev->fr_queue[i];
1563         if (gspca_dev->frame[i].v4l2_buf.flags & V4L2_BUF_FLAG_DONE)
1564                 ret = POLLIN | POLLRDNORM;      /* something to read */
1565         else
1566                 ret = 0;
1567 out:
1568         mutex_unlock(&gspca_dev->queue_lock);
1569         return ret;
1570 }
1571
1572 static ssize_t dev_read(struct file *file, char __user *data,
1573                     size_t count, loff_t *ppos)
1574 {
1575         struct gspca_dev *gspca_dev = file->private_data;
1576         struct gspca_frame *frame;
1577         struct v4l2_buffer v4l2_buf;
1578         struct timeval timestamp;
1579         int n, ret, ret2;
1580
1581         PDEBUG(D_FRAM, "read (%zd)", count);
1582         if (!gspca_dev->present)
1583                 return -ENODEV;
1584         switch (gspca_dev->memory) {
1585         case GSPCA_MEMORY_NO:                   /* first time */
1586                 ret = read_alloc(gspca_dev, file);
1587                 if (ret != 0)
1588                         return ret;
1589                 break;
1590         case GSPCA_MEMORY_READ:
1591                 if (gspca_dev->capt_file == file)
1592                         break;
1593                 /* fall thru */
1594         default:
1595                 return -EINVAL;
1596         }
1597
1598         /* get a frame */
1599         jiffies_to_timeval(get_jiffies_64(), &timestamp);
1600         timestamp.tv_sec--;
1601         n = 2;
1602         for (;;) {
1603                 memset(&v4l2_buf, 0, sizeof v4l2_buf);
1604                 v4l2_buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
1605                 v4l2_buf.memory = GSPCA_MEMORY_READ;
1606                 ret = vidioc_dqbuf(file, gspca_dev, &v4l2_buf);
1607                 if (ret != 0) {
1608                         PDEBUG(D_STREAM, "read dqbuf err %d", ret);
1609                         return ret;
1610                 }
1611
1612                 /* if the process slept for more than 1 second,
1613                  * get anewer frame */
1614                 frame = &gspca_dev->frame[v4l2_buf.index];
1615                 if (--n < 0)
1616                         break;                  /* avoid infinite loop */
1617                 if (frame->v4l2_buf.timestamp.tv_sec >= timestamp.tv_sec)
1618                         break;
1619                 ret = vidioc_qbuf(file, gspca_dev, &v4l2_buf);
1620                 if (ret != 0) {
1621                         PDEBUG(D_STREAM, "read qbuf err %d", ret);
1622                         return ret;
1623                 }
1624         }
1625
1626         /* copy the frame */
1627         if (count > frame->v4l2_buf.bytesused)
1628                 count = frame->v4l2_buf.bytesused;
1629         ret = copy_to_user(data, frame->data, count);
1630         if (ret != 0) {
1631                 PDEBUG(D_ERR|D_STREAM,
1632                         "read cp to user lack %d / %zd", ret, count);
1633                 ret = -EFAULT;
1634                 goto out;
1635         }
1636         ret = count;
1637 out:
1638         /* in each case, requeue the buffer */
1639         ret2 = vidioc_qbuf(file, gspca_dev, &v4l2_buf);
1640         if (ret2 != 0)
1641                 return ret2;
1642         return ret;
1643 }
1644
1645 static void dev_release(struct video_device *vfd)
1646 {
1647         /* nothing */
1648 }
1649
1650 static struct file_operations dev_fops = {
1651         .owner = THIS_MODULE,
1652         .open = dev_open,
1653         .release = dev_close,
1654         .read = dev_read,
1655         .mmap = dev_mmap,
1656         .ioctl = video_ioctl2,
1657 #ifdef CONFIG_COMPAT
1658         .compat_ioctl = v4l_compat_ioctl32,
1659 #endif
1660         .llseek = no_llseek,
1661         .poll   = dev_poll,
1662 };
1663
1664 static const struct v4l2_ioctl_ops dev_ioctl_ops = {
1665         .vidioc_querycap        = vidioc_querycap,
1666         .vidioc_dqbuf           = vidioc_dqbuf,
1667         .vidioc_qbuf            = vidioc_qbuf,
1668         .vidioc_enum_fmt_vid_cap = vidioc_enum_fmt_vid_cap,
1669         .vidioc_try_fmt_vid_cap = vidioc_try_fmt_vid_cap,
1670         .vidioc_g_fmt_vid_cap   = vidioc_g_fmt_vid_cap,
1671         .vidioc_s_fmt_vid_cap   = vidioc_s_fmt_vid_cap,
1672         .vidioc_streamon        = vidioc_streamon,
1673         .vidioc_queryctrl       = vidioc_queryctrl,
1674         .vidioc_g_ctrl          = vidioc_g_ctrl,
1675         .vidioc_s_ctrl          = vidioc_s_ctrl,
1676         .vidioc_querymenu       = vidioc_querymenu,
1677         .vidioc_enum_input      = vidioc_enum_input,
1678         .vidioc_g_input         = vidioc_g_input,
1679         .vidioc_s_input         = vidioc_s_input,
1680         .vidioc_reqbufs         = vidioc_reqbufs,
1681         .vidioc_querybuf        = vidioc_querybuf,
1682         .vidioc_streamoff       = vidioc_streamoff,
1683         .vidioc_g_jpegcomp      = vidioc_g_jpegcomp,
1684         .vidioc_s_jpegcomp      = vidioc_s_jpegcomp,
1685         .vidioc_g_parm          = vidioc_g_parm,
1686         .vidioc_s_parm          = vidioc_s_parm,
1687         .vidioc_s_std           = vidioc_s_std,
1688 #ifdef CONFIG_VIDEO_V4L1_COMPAT
1689         .vidiocgmbuf          = vidiocgmbuf,
1690 #endif
1691 };
1692
1693 static struct video_device gspca_template = {
1694         .name = "gspca main driver",
1695         .fops = &dev_fops,
1696         .ioctl_ops = &dev_ioctl_ops,
1697         .release = dev_release,         /* mandatory */
1698         .minor = -1,
1699 };
1700
1701 /*
1702  * probe and create a new gspca device
1703  *
1704  * This function must be called by the sub-driver when it is
1705  * called for probing a new device.
1706  */
1707 int gspca_dev_probe(struct usb_interface *intf,
1708                 const struct usb_device_id *id,
1709                 const struct sd_desc *sd_desc,
1710                 int dev_size,
1711                 struct module *module)
1712 {
1713         struct usb_interface_descriptor *interface;
1714         struct gspca_dev *gspca_dev;
1715         struct usb_device *dev = interface_to_usbdev(intf);
1716         int ret;
1717
1718         PDEBUG(D_PROBE, "probing %04x:%04x", id->idVendor, id->idProduct);
1719
1720         /* we don't handle multi-config cameras */
1721         if (dev->descriptor.bNumConfigurations != 1)
1722                 return -ENODEV;
1723         interface = &intf->cur_altsetting->desc;
1724         if (interface->bInterfaceNumber > 0)
1725                 return -ENODEV;
1726
1727         /* create the device */
1728         if (dev_size < sizeof *gspca_dev)
1729                 dev_size = sizeof *gspca_dev;
1730         gspca_dev = kzalloc(dev_size, GFP_KERNEL);
1731         if (gspca_dev == NULL) {
1732                 err("couldn't kzalloc gspca struct");
1733                 return -EIO;
1734         }
1735         gspca_dev->dev = dev;
1736         gspca_dev->iface = interface->bInterfaceNumber;
1737         gspca_dev->nbalt = intf->num_altsetting;
1738         gspca_dev->sd_desc = sd_desc;
1739 /*      gspca_dev->users = 0;                   (done by kzalloc) */
1740         gspca_dev->nbufread = 2;
1741
1742         /* configure the subdriver */
1743         ret = gspca_dev->sd_desc->config(gspca_dev, id);
1744         if (ret < 0)
1745                 goto out;
1746         ret = gspca_set_alt0(gspca_dev);
1747         if (ret < 0)
1748                 goto out;
1749         gspca_set_default_mode(gspca_dev);
1750
1751         mutex_init(&gspca_dev->usb_lock);
1752         mutex_init(&gspca_dev->read_lock);
1753         mutex_init(&gspca_dev->queue_lock);
1754         init_waitqueue_head(&gspca_dev->wq);
1755
1756         /* init video stuff */
1757         memcpy(&gspca_dev->vdev, &gspca_template, sizeof gspca_template);
1758         gspca_dev->vdev.parent = &dev->dev;
1759         memcpy(&gspca_dev->fops, &dev_fops, sizeof gspca_dev->fops);
1760         gspca_dev->vdev.fops = &gspca_dev->fops;
1761         gspca_dev->fops.owner = module;         /* module protection */
1762         gspca_dev->present = 1;
1763         ret = video_register_device(&gspca_dev->vdev,
1764                                   VFL_TYPE_GRABBER,
1765                                   video_nr);
1766         if (ret < 0) {
1767                 err("video_register_device err %d", ret);
1768                 goto out;
1769         }
1770
1771         usb_set_intfdata(intf, gspca_dev);
1772         PDEBUG(D_PROBE, "probe ok");
1773         return 0;
1774 out:
1775         kfree(gspca_dev);
1776         return ret;
1777 }
1778 EXPORT_SYMBOL(gspca_dev_probe);
1779
1780 /*
1781  * USB disconnection
1782  *
1783  * This function must be called by the sub-driver
1784  * when the device disconnects, after the specific resources are freed.
1785  */
1786 void gspca_disconnect(struct usb_interface *intf)
1787 {
1788         struct gspca_dev *gspca_dev = usb_get_intfdata(intf);
1789
1790         if (!gspca_dev)
1791                 return;
1792         gspca_dev->present = 0;
1793         mutex_lock(&gspca_dev->queue_lock);
1794         mutex_lock(&gspca_dev->usb_lock);
1795         gspca_dev->streaming = 0;
1796         destroy_urbs(gspca_dev);
1797         mutex_unlock(&gspca_dev->usb_lock);
1798         mutex_unlock(&gspca_dev->queue_lock);
1799         while (gspca_dev->users != 0) {         /* wait until fully closed */
1800                 atomic_inc(&gspca_dev->nevent);
1801                 wake_up_interruptible(&gspca_dev->wq);  /* wake processes */
1802                 schedule();
1803         }
1804 /* We don't want people trying to open up the device */
1805         video_unregister_device(&gspca_dev->vdev);
1806 /* Free the memory */
1807         kfree(gspca_dev);
1808         PDEBUG(D_PROBE, "disconnect complete");
1809 }
1810 EXPORT_SYMBOL(gspca_disconnect);
1811
1812 #ifdef CONFIG_PM
1813 int gspca_suspend(struct usb_interface *intf, pm_message_t message)
1814 {
1815         struct gspca_dev *gspca_dev = usb_get_intfdata(intf);
1816
1817         if (!gspca_dev->streaming)
1818                 return 0;
1819         gspca_dev->frozen = 1;          /* avoid urb error messages */
1820         gspca_dev->sd_desc->stopN(gspca_dev);
1821         destroy_urbs(gspca_dev);
1822         gspca_set_alt0(gspca_dev);
1823         gspca_dev->sd_desc->stop0(gspca_dev);
1824         return 0;
1825 }
1826 EXPORT_SYMBOL(gspca_suspend);
1827
1828 int gspca_resume(struct usb_interface *intf)
1829 {
1830         struct gspca_dev *gspca_dev = usb_get_intfdata(intf);
1831
1832         gspca_dev->frozen = 0;
1833         if (!gspca_dev->streaming)
1834                 return 0;
1835         return gspca_init_transfer(gspca_dev);
1836 }
1837 EXPORT_SYMBOL(gspca_resume);
1838 #endif
1839 /* -- cam driver utility functions -- */
1840
1841 /* auto gain and exposure algorithm based on the knee algorithm described here:
1842    http://ytse.tricolour.net/docs/LowLightOptimization.html
1843
1844    Returns 0 if no changes were made, 1 if the gain and or exposure settings
1845    where changed. */
1846 int gspca_auto_gain_n_exposure(struct gspca_dev *gspca_dev, int avg_lum,
1847         int desired_avg_lum, int deadzone, int gain_knee, int exposure_knee)
1848 {
1849         int i, steps, gain, orig_gain, exposure, orig_exposure, autogain;
1850         const struct ctrl *gain_ctrl = NULL;
1851         const struct ctrl *exposure_ctrl = NULL;
1852         const struct ctrl *autogain_ctrl = NULL;
1853         int retval = 0;
1854
1855         for (i = 0; i < gspca_dev->sd_desc->nctrls; i++) {
1856                 if (gspca_dev->sd_desc->ctrls[i].qctrl.id == V4L2_CID_GAIN)
1857                         gain_ctrl = &gspca_dev->sd_desc->ctrls[i];
1858                 if (gspca_dev->sd_desc->ctrls[i].qctrl.id == V4L2_CID_EXPOSURE)
1859                         exposure_ctrl = &gspca_dev->sd_desc->ctrls[i];
1860                 if (gspca_dev->sd_desc->ctrls[i].qctrl.id == V4L2_CID_AUTOGAIN)
1861                         autogain_ctrl = &gspca_dev->sd_desc->ctrls[i];
1862         }
1863         if (!gain_ctrl || !exposure_ctrl || !autogain_ctrl) {
1864                 PDEBUG(D_ERR, "Error: gspca_auto_gain_n_exposure called "
1865                         "on cam without (auto)gain/exposure");
1866                 return 0;
1867         }
1868
1869         if (gain_ctrl->get(gspca_dev, &gain) ||
1870                         exposure_ctrl->get(gspca_dev, &exposure) ||
1871                         autogain_ctrl->get(gspca_dev, &autogain) || !autogain)
1872                 return 0;
1873
1874         orig_gain = gain;
1875         orig_exposure = exposure;
1876
1877         /* If we are of a multiple of deadzone, do multiple steps to reach the
1878            desired lumination fast (with the risc of a slight overshoot) */
1879         steps = abs(desired_avg_lum - avg_lum) / deadzone;
1880
1881         PDEBUG(D_FRAM, "autogain: lum: %d, desired: %d, steps: %d\n",
1882                 avg_lum, desired_avg_lum, steps);
1883
1884         for (i = 0; i < steps; i++) {
1885                 if (avg_lum > desired_avg_lum) {
1886                         if (gain > gain_knee)
1887                                 gain--;
1888                         else if (exposure > exposure_knee)
1889                                 exposure--;
1890                         else if (gain > gain_ctrl->qctrl.default_value)
1891                                 gain--;
1892                         else if (exposure > exposure_ctrl->qctrl.minimum)
1893                                 exposure--;
1894                         else if (gain > gain_ctrl->qctrl.minimum)
1895                                 gain--;
1896                         else
1897                                 break;
1898                 } else {
1899                         if (gain < gain_ctrl->qctrl.default_value)
1900                                 gain++;
1901                         else if (exposure < exposure_knee)
1902                                 exposure++;
1903                         else if (gain < gain_knee)
1904                                 gain++;
1905                         else if (exposure < exposure_ctrl->qctrl.maximum)
1906                                 exposure++;
1907                         else if (gain < gain_ctrl->qctrl.maximum)
1908                                 gain++;
1909                         else
1910                                 break;
1911                 }
1912         }
1913
1914         if (gain != orig_gain) {
1915                 gain_ctrl->set(gspca_dev, gain);
1916                 retval = 1;
1917         }
1918         if (exposure != orig_exposure) {
1919                 exposure_ctrl->set(gspca_dev, exposure);
1920                 retval = 1;
1921         }
1922
1923         return retval;
1924 }
1925 EXPORT_SYMBOL(gspca_auto_gain_n_exposure);
1926
1927 /* -- module insert / remove -- */
1928 static int __init gspca_init(void)
1929 {
1930         info("main v%d.%d.%d registered",
1931                 (DRIVER_VERSION_NUMBER >> 16) & 0xff,
1932                 (DRIVER_VERSION_NUMBER >> 8) & 0xff,
1933                 DRIVER_VERSION_NUMBER & 0xff);
1934         return 0;
1935 }
1936 static void __exit gspca_exit(void)
1937 {
1938         info("main deregistered");
1939 }
1940
1941 module_init(gspca_init);
1942 module_exit(gspca_exit);
1943
1944 #ifdef GSPCA_DEBUG
1945 module_param_named(debug, gspca_debug, int, 0644);
1946 MODULE_PARM_DESC(debug,
1947                 "Debug (bit) 0x01:error 0x02:probe 0x04:config"
1948                 " 0x08:stream 0x10:frame 0x20:packet 0x40:USBin 0x80:USBout"
1949                 " 0x0100: v4l2");
1950 #endif