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
  36 #include "gspca.h"
  37
  38 /* global values */
  39 #define DEF_NURBS 2             /* default number of URBs */
  40
  41 MODULE_AUTHOR("Jean-Francois Moine <http://moinejf.free.fr>");
  42 MODULE_DESCRIPTION("GSPCA USB Camera Driver");
  43 MODULE_LICENSE("GPL");
  44
  45 #define DRIVER_VERSION_NUMBER   KERNEL_VERSION(2, 1, 7)
  46 static const char version[] = "2.1.7";
  47
  48 static int video_nr = -1;
  49
  50 #ifdef CONFIG_VIDEO_ADV_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                 PDEBUG(D_ERR|D_PACK, "urb status: %d", urb->status);
 118                 return;         /* disconnection ? */
 119         }
 120         pkt_scan = gspca_dev->sd_desc->pkt_scan;
 121         for (i = 0; i < urb->number_of_packets; i++) {
 122
 123                 /* check the availability of the frame buffer */
 124                 j = gspca_dev->fr_i;
 125                 j = gspca_dev->fr_queue[j];
 126                 frame = &gspca_dev->frame[j];
 127                 if ((frame->v4l2_buf.flags & BUF_ALL_FLAGS)
 128                                         != V4L2_BUF_FLAG_QUEUED) {
 129                         gspca_dev->last_packet_type = DISCARD_PACKET;
 130                         break;
 131                 }
 132
 133                 /* check the packet status and length */
 134                 len = urb->iso_frame_desc[i].actual_length;
 135                 if (len == 0)
 136                         continue;
 137                 st = urb->iso_frame_desc[i].status;
 138                 if (st) {
 139                         PDEBUG(D_ERR,
 140                                 "ISOC data error: [%d] len=%d, status=%d",
 141                                 i, len, st);
 142                         gspca_dev->last_packet_type = DISCARD_PACKET;
 143                         continue;
 144                 }
 145
 146                 /* let the packet be analyzed by the subdriver */
 147                 PDEBUG(D_PACK, "packet [%d] o:%d l:%d",
 148                         i, urb->iso_frame_desc[i].offset, len);
 149                 data = (__u8 *) urb->transfer_buffer
 150                                         + urb->iso_frame_desc[i].offset;
 151                 pkt_scan(gspca_dev, frame, data, len);
 152         }
 153
 154         /* resubmit the URB */
 155         urb->status = 0;
 156         st = usb_submit_urb(urb, GFP_ATOMIC);
 157         if (st < 0)
 158                 PDEBUG(D_ERR|D_PACK, "usb_submit_urb() ret %d", st);
 159 }
 160
 161 /*
 162  * ISOC message interrupt from the USB device
 163  *
 164  * Analyse each packet and call the subdriver for copy to the frame buffer.
 165  */
 166 static void isoc_irq(struct urb *urb
 167 )
 168 {
 169         struct gspca_dev *gspca_dev = (struct gspca_dev *) urb->context;
 170
 171         PDEBUG(D_PACK, "isoc irq");
 172         if (!gspca_dev->streaming)
 173                 return;
 174         fill_frame(gspca_dev, urb);
 175 }
 176
 177 /*
 178  * add data to the current frame
 179  *
 180  * This function is called by the subdrivers at interrupt level.
 181  *
 182  * To build a frame, these ones must add
 183  *      - one FIRST_PACKET
 184  *      - 0 or many INTER_PACKETs
 185  *      - one LAST_PACKET
 186  * DISCARD_PACKET invalidates the whole frame.
 187  * On LAST_PACKET, a new frame is returned.
 188  */
 189 struct gspca_frame *gspca_frame_add(struct gspca_dev *gspca_dev,
 190                                     int packet_type,
 191                                     struct gspca_frame *frame,
 192                                     const __u8 *data,
 193                                     int len)
 194 {
 195         int i, j;
 196
 197         PDEBUG(D_PACK, "add t:%d l:%d", packet_type, len);
 198
 199         /* when start of a new frame, if the current frame buffer
 200          * is not queued, discard the whole frame */
 201         if (packet_type == FIRST_PACKET) {
 202                 if ((frame->v4l2_buf.flags & BUF_ALL_FLAGS)
 203                                                 != V4L2_BUF_FLAG_QUEUED) {
 204                         gspca_dev->last_packet_type = DISCARD_PACKET;
 205                         return frame;
 206                 }
 207                 frame->data_end = frame->data;
 208                 jiffies_to_timeval(get_jiffies_64(),
 209                                    &frame->v4l2_buf.timestamp);
 210                 frame->v4l2_buf.sequence = ++gspca_dev->sequence;
 211         } else if (gspca_dev->last_packet_type == DISCARD_PACKET) {
 212                 return frame;
 213         }
 214
 215         /* append the packet to the frame buffer */
 216         if (len > 0) {
 217                 if (frame->data_end - frame->data + len
 218                                                  > frame->v4l2_buf.length) {
 219                         PDEBUG(D_ERR|D_PACK, "frame overflow %zd > %d",
 220                                 frame->data_end - frame->data + len,
 221                                 frame->v4l2_buf.length);
 222                         packet_type = DISCARD_PACKET;
 223                 } else {
 224                         memcpy(frame->data_end, data, len);
 225                         frame->data_end += len;
 226                 }
 227         }
 228         gspca_dev->last_packet_type = packet_type;
 229
 230         /* if last packet, wake the application and advance in the queue */
 231         if (packet_type == LAST_PACKET) {
 232                 frame->v4l2_buf.bytesused = frame->data_end - frame->data;
 233                 frame->v4l2_buf.flags &= ~V4L2_BUF_FLAG_QUEUED;
 234                 frame->v4l2_buf.flags |= V4L2_BUF_FLAG_DONE;
 235                 atomic_inc(&gspca_dev->nevent);
 236                 wake_up_interruptible(&gspca_dev->wq);  /* event = new frame */
 237                 i = (gspca_dev->fr_i + 1) % gspca_dev->nframes;
 238                 gspca_dev->fr_i = i;
 239                 PDEBUG(D_FRAM, "frame complete len:%d q:%d i:%d o:%d",
 240                         frame->v4l2_buf.bytesused,
 241                         gspca_dev->fr_q,
 242                         i,
 243                         gspca_dev->fr_o);
 244                 j = gspca_dev->fr_queue[i];
 245                 frame = &gspca_dev->frame[j];
 246         }
 247         return frame;
 248 }
 249 EXPORT_SYMBOL(gspca_frame_add);
 250
 251 static int gspca_is_compressed(__u32 format)
 252 {
 253         switch (format) {
 254         case V4L2_PIX_FMT_MJPEG:
 255         case V4L2_PIX_FMT_JPEG:
 256         case V4L2_PIX_FMT_SPCA561:
 257         case V4L2_PIX_FMT_PAC207:
 258                 return 1;
 259         }
 260         return 0;
 261 }
 262
 263 static void *rvmalloc(unsigned long size)
 264 {
 265         void *mem;
 266         unsigned long adr;
 267
 268 /*      size = PAGE_ALIGN(size);        (already done) */
 269         mem = vmalloc_32(size);
 270         if (mem != NULL) {
 271                 adr = (unsigned long) mem;
 272                 while ((long) size > 0) {
 273                         SetPageReserved(vmalloc_to_page((void *) adr));
 274                         adr += PAGE_SIZE;
 275                         size -= PAGE_SIZE;
 276                 }
 277         }
 278         return mem;
 279 }
 280
 281 static void rvfree(void *mem, long size)
 282 {
 283         unsigned long adr;
 284
 285         adr = (unsigned long) mem;
 286         while (size > 0) {
 287                 ClearPageReserved(vmalloc_to_page((void *) adr));
 288                 adr += PAGE_SIZE;
 289                 size -= PAGE_SIZE;
 290         }
 291         vfree(mem);
 292 }
 293
 294 static int frame_alloc(struct gspca_dev *gspca_dev,
 295                         unsigned int count)
 296 {
 297         struct gspca_frame *frame;
 298         unsigned int frsz;
 299         int i;
 300
 301         i = gspca_dev->curr_mode;
 302         frsz = gspca_dev->cam.cam_mode[i].sizeimage;
 303         PDEBUG(D_STREAM, "frame alloc frsz: %d", frsz);
 304         frsz = PAGE_ALIGN(frsz);
 305         gspca_dev->frsz = frsz;
 306         if (count > GSPCA_MAX_FRAMES)
 307                 count = GSPCA_MAX_FRAMES;
 308         gspca_dev->frbuf = rvmalloc(frsz * count);
 309         if (!gspca_dev->frbuf) {
 310                 err("frame alloc failed");
 311                 return -ENOMEM;
 312         }
 313         gspca_dev->nframes = count;
 314         for (i = 0; i < count; i++) {
 315                 frame = &gspca_dev->frame[i];
 316                 frame->v4l2_buf.index = i;
 317                 frame->v4l2_buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
 318                 frame->v4l2_buf.flags = 0;
 319                 frame->v4l2_buf.field = V4L2_FIELD_NONE;
 320                 frame->v4l2_buf.length = frsz;
 321                 frame->v4l2_buf.memory = gspca_dev->memory;
 322                 frame->v4l2_buf.sequence = 0;
 323                 frame->data = frame->data_end =
 324                                         gspca_dev->frbuf + i * frsz;
 325                 frame->v4l2_buf.m.offset = i * frsz;
 326         }
 327         gspca_dev->fr_i = gspca_dev->fr_o = gspca_dev->fr_q = 0;
 328         gspca_dev->last_packet_type = DISCARD_PACKET;
 329         gspca_dev->sequence = 0;
 330         atomic_set(&gspca_dev->nevent, 0);
 331         return 0;
 332 }
 333
 334 static void frame_free(struct gspca_dev *gspca_dev)
 335 {
 336         int i;
 337
 338         PDEBUG(D_STREAM, "frame free");
 339         if (gspca_dev->frbuf != NULL) {
 340                 rvfree(gspca_dev->frbuf,
 341                         gspca_dev->nframes * gspca_dev->frsz);
 342                 gspca_dev->frbuf = NULL;
 343                 for (i = 0; i < gspca_dev->nframes; i++)
 344                         gspca_dev->frame[i].data = NULL;
 345         }
 346         gspca_dev->nframes = 0;
 347 }
 348
 349 static void destroy_urbs(struct gspca_dev *gspca_dev)
 350 {
 351         struct urb *urb;
 352         unsigned int i;
 353
 354         PDEBUG(D_STREAM, "kill transfer");
 355         for (i = 0; i < MAX_NURBS; ++i) {
 356                 urb = gspca_dev->urb[i];
 357                 if (urb == NULL)
 358                         break;
 359
 360                 gspca_dev->urb[i] = NULL;
 361                 usb_kill_urb(urb);
 362                 if (urb->transfer_buffer != NULL)
 363                         usb_buffer_free(gspca_dev->dev,
 364                                         urb->transfer_buffer_length,
 365                                         urb->transfer_buffer,
 366                                         urb->transfer_dma);
 367                 usb_free_urb(urb);
 368         }
 369 }
 370
 371 /*
 372  * search an input isochronous endpoint in an alternate setting
 373  */
 374 static struct usb_host_endpoint *alt_isoc(struct usb_host_interface *alt,
 375                                           __u8 epaddr)
 376 {
 377         struct usb_host_endpoint *ep;
 378         int i, attr;
 379
 380         epaddr |= USB_DIR_IN;
 381         for (i = 0; i < alt->desc.bNumEndpoints; i++) {
 382                 ep = &alt->endpoint[i];
 383                 if (ep->desc.bEndpointAddress == epaddr) {
 384                         attr = ep->desc.bmAttributes
 385                                                 & USB_ENDPOINT_XFERTYPE_MASK;
 386                         if (attr == USB_ENDPOINT_XFER_ISOC)
 387                                 return ep;
 388                         break;
 389                 }
 390         }
 391         return NULL;
 392 }
 393
 394 /*
 395  * search an input isochronous endpoint
 396  *
 397  * The endpoint is defined by the subdriver.
 398  * Use only the first isoc (some Zoran - 0x0572:0x0001 - have two such ep).
 399  * This routine may be called many times when the bandwidth is too small
 400  * (the bandwidth is checked on urb submit).
 401  */
 402 struct usb_host_endpoint *get_isoc_ep(struct gspca_dev *gspca_dev)
 403 {
 404         struct usb_interface *intf;
 405         struct usb_host_endpoint *ep;
 406         int i, ret;
 407
 408         intf = usb_ifnum_to_if(gspca_dev->dev, gspca_dev->iface);
 409         ep = NULL;
 410         i = gspca_dev->alt;                     /* previous alt setting */
 411         while (--i > 0) {                       /* alt 0 is unusable */
 412                 ep = alt_isoc(&intf->altsetting[i], gspca_dev->cam.epaddr);
 413                 if (ep)
 414                         break;
 415         }
 416         if (ep == NULL) {
 417                 err("no ISOC endpoint found");
 418                 return NULL;
 419         }
 420         PDEBUG(D_STREAM, "use ISOC alt %d ep 0x%02x",
 421                         i, ep->desc.bEndpointAddress);
 422         ret = usb_set_interface(gspca_dev->dev, gspca_dev->iface, i);
 423         if (ret < 0) {
 424                 err("set interface err %d", ret);
 425                 return NULL;
 426         }
 427         gspca_dev->alt = i;             /* memorize the current alt setting */
 428         return ep;
 429 }
 430
 431 /*
 432  * create the isochronous URBs
 433  */
 434 static int create_urbs(struct gspca_dev *gspca_dev,
 435                         struct usb_host_endpoint *ep)
 436 {
 437         struct urb *urb;
 438         int n, nurbs, i, psize, npkt, bsize;
 439
 440         /* calculate the packet size and the number of packets */
 441         psize = le16_to_cpu(ep->desc.wMaxPacketSize);
 442
 443         /* See paragraph 5.9 / table 5-11 of the usb 2.0 spec. */
 444         psize = (psize & 0x07ff) * (1 + ((psize >> 11) & 3));
 445         npkt = ISO_MAX_SIZE / psize;
 446         if (npkt > ISO_MAX_PKT)
 447                 npkt = ISO_MAX_PKT;
 448         bsize = psize * npkt;
 449         PDEBUG(D_STREAM,
 450                 "isoc %d pkts size %d (bsize:%d)", npkt, psize, bsize);
 451         nurbs = DEF_NURBS;
 452         gspca_dev->nurbs = nurbs;
 453         for (n = 0; n < nurbs; n++) {
 454                 urb = usb_alloc_urb(npkt, GFP_KERNEL);
 455                 if (!urb) {
 456                         err("usb_alloc_urb failed");
 457                         return -ENOMEM;
 458                 }
 459                 urb->transfer_buffer = usb_buffer_alloc(gspca_dev->dev,
 460                                                 bsize,
 461                                                 GFP_KERNEL,
 462                                                 &urb->transfer_dma);
 463
 464                 if (urb->transfer_buffer == NULL) {
 465                         usb_free_urb(urb);
 466                         destroy_urbs(gspca_dev);
 467                         err("usb_buffer_urb failed");
 468                         return -ENOMEM;
 469                 }
 470                 gspca_dev->urb[n] = urb;
 471                 urb->dev = gspca_dev->dev;
 472                 urb->context = gspca_dev;
 473                 urb->pipe = usb_rcvisocpipe(gspca_dev->dev,
 474                                             ep->desc.bEndpointAddress);
 475                 urb->transfer_flags = URB_ISO_ASAP
 476                                         | URB_NO_TRANSFER_DMA_MAP;
 477                 urb->interval = ep->desc.bInterval;
 478                 urb->complete = isoc_irq;
 479                 urb->number_of_packets = npkt;
 480                 urb->transfer_buffer_length = bsize;
 481                 for (i = 0; i < npkt; i++) {
 482                         urb->iso_frame_desc[i].length = psize;
 483                         urb->iso_frame_desc[i].offset = psize * i;
 484                 }
 485         }
 486         return 0;
 487 }
 488
 489 /*
 490  * start the USB transfer
 491  */
 492 static int gspca_init_transfer(struct gspca_dev *gspca_dev)
 493 {
 494         struct usb_host_endpoint *ep;
 495         int n, ret;
 496
 497         if (mutex_lock_interruptible(&gspca_dev->usb_lock))
 498                 return -ERESTARTSYS;
 499
 500         /* set the higher alternate setting and
 501          * loop until urb submit succeeds */
 502         gspca_dev->alt = gspca_dev->nbalt;
 503         for (;;) {
 504                 PDEBUG(D_STREAM, "init transfer alt %d", gspca_dev->alt);
 505                 ep = get_isoc_ep(gspca_dev);
 506                 if (ep == NULL) {
 507                         ret = -EIO;
 508                         goto out;
 509                 }
 510                 ret = create_urbs(gspca_dev, ep);
 511                 if (ret < 0)
 512                         goto out;
 513
 514                 /* start the cam */
 515                 gspca_dev->sd_desc->start(gspca_dev);
 516                 gspca_dev->streaming = 1;
 517                 atomic_set(&gspca_dev->nevent, 0);
 518
 519                 /* submit the URBs */
 520                 for (n = 0; n < gspca_dev->nurbs; n++) {
 521                         ret = usb_submit_urb(gspca_dev->urb[n], GFP_KERNEL);
 522                         if (ret < 0) {
 523                                 PDEBUG(D_ERR|D_STREAM,
 524                                         "usb_submit_urb [%d] err %d", n, ret);
 525                                 gspca_dev->streaming = 0;
 526                                 destroy_urbs(gspca_dev);
 527                                 if (ret == -ENOSPC)
 528                                         break;  /* try the previous alt */
 529                                 goto out;
 530                         }
 531                 }
 532                 if (ret >= 0)
 533                         break;
 534         }
 535 out:
 536         mutex_unlock(&gspca_dev->usb_lock);
 537         return ret;
 538 }
 539
 540 static int gspca_set_alt0(struct gspca_dev *gspca_dev)
 541 {
 542         int ret;
 543
 544         ret = usb_set_interface(gspca_dev->dev, gspca_dev->iface, 0);
 545         if (ret < 0)
 546                 PDEBUG(D_ERR|D_STREAM, "set interface 0 err %d", ret);
 547         return ret;
 548 }
 549
 550 /* Note both the queue and the usb lock should be hold when calling this */
 551 static void gspca_stream_off(struct gspca_dev *gspca_dev)
 552 {
 553         gspca_dev->streaming = 0;
 554         atomic_set(&gspca_dev->nevent, 0);
 555         if (gspca_dev->present) {
 556                 gspca_dev->sd_desc->stopN(gspca_dev);
 557                 destroy_urbs(gspca_dev);
 558                 gspca_set_alt0(gspca_dev);
 559                 gspca_dev->sd_desc->stop0(gspca_dev);
 560                 PDEBUG(D_STREAM, "stream off OK");
 561         }
 562 }
 563
 564 static void gspca_set_default_mode(struct gspca_dev *gspca_dev)
 565 {
 566         int i;
 567
 568         i = gspca_dev->cam.nmodes - 1;  /* take the highest mode */
 569         gspca_dev->curr_mode = i;
 570         gspca_dev->width = gspca_dev->cam.cam_mode[i].width;
 571         gspca_dev->height = gspca_dev->cam.cam_mode[i].height;
 572         gspca_dev->pixfmt = gspca_dev->cam.cam_mode[i].pixelformat;
 573 }
 574
 575 static int wxh_to_mode(struct gspca_dev *gspca_dev,
 576                         int width, int height)
 577 {
 578         int i;
 579
 580         for (i = gspca_dev->cam.nmodes; --i > 0; ) {
 581                 if (width >= gspca_dev->cam.cam_mode[i].width
 582                     && height >= gspca_dev->cam.cam_mode[i].height)
 583                         break;
 584         }
 585         return i;
 586 }
 587
 588 /*
 589  * search a mode with the right pixel format
 590  */
 591 static int gspca_get_mode(struct gspca_dev *gspca_dev,
 592                         int mode,
 593                         int pixfmt)
 594 {
 595         int modeU, modeD;
 596
 597         modeU = modeD = mode;
 598         while ((modeU < gspca_dev->cam.nmodes) || modeD >= 0) {
 599                 if (--modeD >= 0) {
 600                         if (gspca_dev->cam.cam_mode[modeD].pixelformat
 601                                                                 == pixfmt)
 602                                 return modeD;
 603                 }
 604                 if (++modeU < gspca_dev->cam.nmodes) {
 605                         if (gspca_dev->cam.cam_mode[modeU].pixelformat
 606                                                                 == pixfmt)
 607                                 return modeU;
 608                 }
 609         }
 610         return -EINVAL;
 611 }
 612
 613 static int vidioc_enum_fmt_vid_cap(struct file *file, void  *priv,
 614                                 struct v4l2_fmtdesc *fmtdesc)
 615 {
 616         struct gspca_dev *gspca_dev = priv;
 617         int i, j, index;
 618         __u32 fmt_tb[8];
 619
 620         /* give an index to each format */
 621         index = 0;
 622         j = 0;
 623         for (i = gspca_dev->cam.nmodes; --i >= 0; ) {
 624                 fmt_tb[index] = gspca_dev->cam.cam_mode[i].pixelformat;
 625                 j = 0;
 626                 for (;;) {
 627                         if (fmt_tb[j] == fmt_tb[index])
 628                                 break;
 629                         j++;
 630                 }
 631                 if (j == index) {
 632                         if (fmtdesc->index == index)
 633                                 break;          /* new format */
 634                         index++;
 635                         if (index >= sizeof fmt_tb / sizeof fmt_tb[0])
 636                                 return -EINVAL;
 637                 }
 638         }
 639         if (i < 0)
 640                 return -EINVAL;         /* no more format */
 641
 642         fmtdesc->pixelformat = fmt_tb[index];
 643         if (gspca_is_compressed(fmt_tb[index]))
 644                 fmtdesc->flags = V4L2_FMT_FLAG_COMPRESSED;
 645         fmtdesc->type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
 646         fmtdesc->description[0] = fmtdesc->pixelformat & 0xff;
 647         fmtdesc->description[1] = (fmtdesc->pixelformat >> 8) & 0xff;
 648         fmtdesc->description[2] = (fmtdesc->pixelformat >> 16) & 0xff;
 649         fmtdesc->description[3] = fmtdesc->pixelformat >> 24;
 650         fmtdesc->description[4] = '\0';
 651         return 0;
 652 }
 653
 654 static int vidioc_g_fmt_vid_cap(struct file *file, void *priv,
 655                             struct v4l2_format *fmt)
 656 {
 657         struct gspca_dev *gspca_dev = priv;
 658         int mode;
 659
 660         if (fmt->type != V4L2_BUF_TYPE_VIDEO_CAPTURE)
 661                 return -EINVAL;
 662         mode = gspca_dev->curr_mode;
 663         memcpy(&fmt->fmt.pix, &gspca_dev->cam.cam_mode[mode],
 664                 sizeof fmt->fmt.pix);
 665         return 0;
 666 }
 667
 668 static int try_fmt_vid_cap(struct gspca_dev *gspca_dev,
 669                         struct v4l2_format *fmt)
 670 {
 671         int w, h, mode, mode2;
 672
 673         if (fmt->type != V4L2_BUF_TYPE_VIDEO_CAPTURE)
 674                 return -EINVAL;
 675         w = fmt->fmt.pix.width;
 676         h = fmt->fmt.pix.height;
 677
 678 #ifdef CONFIG_VIDEO_ADV_DEBUG
 679         if (gspca_debug & D_CONF)
 680                 PDEBUG_MODE("try fmt cap", fmt->fmt.pix.pixelformat, w, h);
 681 #endif
 682         /* search the closest mode for width and height */
 683         mode = wxh_to_mode(gspca_dev, w, h);
 684
 685         /* OK if right palette */
 686         if (gspca_dev->cam.cam_mode[mode].pixelformat
 687                                                 != fmt->fmt.pix.pixelformat) {
 688
 689                 /* else, search the closest mode with the same pixel format */
 690                 mode2 = gspca_get_mode(gspca_dev, mode,
 691                                         fmt->fmt.pix.pixelformat);
 692                 if (mode2 >= 0)
 693                         mode = mode2;
 694 /*              else
 695                         ;                * no chance, return this mode */
 696         }
 697         memcpy(&fmt->fmt.pix, &gspca_dev->cam.cam_mode[mode],
 698                 sizeof fmt->fmt.pix);
 699         return mode;                    /* used when s_fmt */
 700 }
 701
 702 static int vidioc_try_fmt_vid_cap(struct file *file,
 703                               void *priv,
 704                               struct v4l2_format *fmt)
 705 {
 706         struct gspca_dev *gspca_dev = priv;
 707         int ret;
 708
 709         ret = try_fmt_vid_cap(gspca_dev, fmt);
 710         if (ret < 0)
 711                 return ret;
 712         return 0;
 713 }
 714
 715 static int vidioc_s_fmt_vid_cap(struct file *file, void *priv,
 716                             struct v4l2_format *fmt)
 717 {
 718         struct gspca_dev *gspca_dev = priv;
 719         int ret;
 720
 721         if (mutex_lock_interruptible(&gspca_dev->queue_lock))
 722                 return -ERESTARTSYS;
 723
 724         ret = try_fmt_vid_cap(gspca_dev, fmt);
 725         if (ret < 0)
 726                 goto out;
 727
 728         if (gspca_dev->nframes != 0
 729             && fmt->fmt.pix.sizeimage > gspca_dev->frsz) {
 730                 ret = -EINVAL;
 731                 goto out;
 732         }
 733
 734         if (ret == gspca_dev->curr_mode) {
 735                 ret = 0;
 736                 goto out;                       /* same mode */
 737         }
 738
 739         if (gspca_dev->streaming) {
 740                 ret = -EBUSY;
 741                 goto out;
 742         }
 743         gspca_dev->width = fmt->fmt.pix.width;
 744         gspca_dev->height = fmt->fmt.pix.height;
 745         gspca_dev->pixfmt = fmt->fmt.pix.pixelformat;
 746         gspca_dev->curr_mode = ret;
 747
 748         ret = 0;
 749 out:
 750         mutex_unlock(&gspca_dev->queue_lock);
 751         return ret;
 752 }
 753
 754 static int dev_open(struct inode *inode, struct file *file)
 755 {
 756         struct gspca_dev *gspca_dev;
 757         int ret;
 758
 759         PDEBUG(D_STREAM, "%s open", current->comm);
 760         gspca_dev = (struct gspca_dev *) video_devdata(file);
 761         if (mutex_lock_interruptible(&gspca_dev->queue_lock))
 762                 return -ERESTARTSYS;
 763         if (!gspca_dev->present) {
 764                 ret = -ENODEV;
 765                 goto out;
 766         }
 767
 768         /* if not done yet, initialize the sensor */
 769         if (gspca_dev->users == 0) {
 770                 if (mutex_lock_interruptible(&gspca_dev->usb_lock)) {
 771                         ret = -ERESTARTSYS;
 772                         goto out;
 773                 }
 774                 ret = gspca_dev->sd_desc->open(gspca_dev);
 775                 mutex_unlock(&gspca_dev->usb_lock);
 776                 if (ret != 0) {
 777                         PDEBUG(D_ERR|D_CONF, "init device failed %d", ret);
 778                         goto out;
 779                 }
 780         } else if (gspca_dev->users > 4) {      /* (arbitrary value) */
 781                 ret = -EBUSY;
 782                 goto out;
 783         }
 784         gspca_dev->users++;
 785         file->private_data = gspca_dev;
 786 #ifdef CONFIG_VIDEO_ADV_DEBUG
 787         /* activate the v4l2 debug */
 788         if (gspca_debug & D_V4L2)
 789                 gspca_dev->vdev.debug |= 3;
 790         else
 791                 gspca_dev->vdev.debug &= ~3;
 792 #endif
 793 out:
 794         mutex_unlock(&gspca_dev->queue_lock);
 795         if (ret != 0)
 796                 PDEBUG(D_ERR|D_STREAM, "open failed err %d", ret);
 797         else
 798                 PDEBUG(D_STREAM, "open done");
 799         return ret;
 800 }
 801
 802 static int dev_close(struct inode *inode, struct file *file)
 803 {
 804         struct gspca_dev *gspca_dev = file->private_data;
 805
 806         PDEBUG(D_STREAM, "%s close", current->comm);
 807         if (mutex_lock_interruptible(&gspca_dev->queue_lock))
 808                 return -ERESTARTSYS;
 809         gspca_dev->users--;
 810
 811         /* if the file did the capture, free the streaming resources */
 812         if (gspca_dev->capt_file == file) {
 813                 mutex_lock(&gspca_dev->usb_lock);
 814                 if (gspca_dev->streaming)
 815                         gspca_stream_off(gspca_dev);
 816                 gspca_dev->sd_desc->close(gspca_dev);
 817                 mutex_unlock(&gspca_dev->usb_lock);
 818                 frame_free(gspca_dev);
 819                 gspca_dev->capt_file = NULL;
 820                 gspca_dev->memory = GSPCA_MEMORY_NO;
 821         }
 822         file->private_data = NULL;
 823         mutex_unlock(&gspca_dev->queue_lock);
 824         PDEBUG(D_STREAM, "close done");
 825         return 0;
 826 }
 827
 828 static int vidioc_querycap(struct file *file, void  *priv,
 829                            struct v4l2_capability *cap)
 830 {
 831         struct gspca_dev *gspca_dev = priv;
 832
 833         memset(cap, 0, sizeof *cap);
 834         strncpy(cap->driver, gspca_dev->sd_desc->name, sizeof cap->driver);
 835         strncpy(cap->card, gspca_dev->cam.dev_name, sizeof cap->card);
 836         strncpy(cap->bus_info, gspca_dev->dev->bus->bus_name,
 837                 sizeof cap->bus_info);
 838         cap->version = DRIVER_VERSION_NUMBER;
 839         cap->capabilities = V4L2_CAP_VIDEO_CAPTURE
 840                           | V4L2_CAP_STREAMING
 841                           | V4L2_CAP_READWRITE;
 842         return 0;
 843 }
 844
 845 /* the use of V4L2_CTRL_FLAG_NEXT_CTRL asks for the controls to be sorted */
 846 static int vidioc_queryctrl(struct file *file, void *priv,
 847                            struct v4l2_queryctrl *q_ctrl)
 848 {
 849         struct gspca_dev *gspca_dev = priv;
 850         int i;
 851         u32 id;
 852
 853         id = q_ctrl->id;
 854         if (id & V4L2_CTRL_FLAG_NEXT_CTRL) {
 855                 id &= V4L2_CTRL_ID_MASK;
 856                 id++;
 857                 for (i = 0; i < gspca_dev->sd_desc->nctrls; i++) {
 858                         if (id >= gspca_dev->sd_desc->ctrls[i].qctrl.id) {
 859                                 memcpy(q_ctrl,
 860                                         &gspca_dev->sd_desc->ctrls[i].qctrl,
 861                                         sizeof *q_ctrl);
 862                                 return 0;
 863                         }
 864                 }
 865                 return -EINVAL;
 866         }
 867         for (i = 0; i < gspca_dev->sd_desc->nctrls; i++) {
 868                 if (id == gspca_dev->sd_desc->ctrls[i].qctrl.id) {
 869                         memcpy(q_ctrl,
 870                                 &gspca_dev->sd_desc->ctrls[i].qctrl,
 871                                 sizeof *q_ctrl);
 872                         return 0;
 873                 }
 874         }
 875         if (id >= V4L2_CID_BASE
 876             && id <= V4L2_CID_LASTP1) {
 877                 q_ctrl->flags |= V4L2_CTRL_FLAG_DISABLED;
 878                 return 0;
 879         }
 880         return -EINVAL;
 881 }
 882
 883 static int vidioc_s_ctrl(struct file *file, void *priv,
 884                          struct v4l2_control *ctrl)
 885 {
 886         struct gspca_dev *gspca_dev = priv;
 887         const struct ctrl *ctrls;
 888         int i, ret;
 889
 890         for (i = 0, ctrls = gspca_dev->sd_desc->ctrls;
 891              i < gspca_dev->sd_desc->nctrls;
 892              i++, ctrls++) {
 893                 if (ctrl->id != ctrls->qctrl.id)
 894                         continue;
 895                 if (ctrl->value < ctrls->qctrl.minimum
 896                     && ctrl->value > ctrls->qctrl.maximum)
 897                         return -ERANGE;
 898                 PDEBUG(D_CONF, "set ctrl [%08x] = %d", ctrl->id, ctrl->value);
 899                 if (mutex_lock_interruptible(&gspca_dev->usb_lock))
 900                         return -ERESTARTSYS;
 901                 ret = ctrls->set(gspca_dev, ctrl->value);
 902                 mutex_unlock(&gspca_dev->usb_lock);
 903                 return ret;
 904         }
 905         return -EINVAL;
 906 }
 907
 908 static int vidioc_g_ctrl(struct file *file, void *priv,
 909                          struct v4l2_control *ctrl)
 910 {
 911         struct gspca_dev *gspca_dev = priv;
 912
 913         const struct ctrl *ctrls;
 914         int i, ret;
 915
 916         for (i = 0, ctrls = gspca_dev->sd_desc->ctrls;
 917              i < gspca_dev->sd_desc->nctrls;
 918              i++, ctrls++) {
 919                 if (ctrl->id != ctrls->qctrl.id)
 920                         continue;
 921                 if (mutex_lock_interruptible(&gspca_dev->usb_lock))
 922                         return -ERESTARTSYS;
 923                 ret = ctrls->get(gspca_dev, &ctrl->value);
 924                 mutex_unlock(&gspca_dev->usb_lock);
 925                 return ret;
 926         }
 927         return -EINVAL;
 928 }
 929
 930 static int vidioc_querymenu(struct file *file, void *priv,
 931                             struct v4l2_querymenu *qmenu)
 932 {
 933         struct gspca_dev *gspca_dev = priv;
 934
 935         if (!gspca_dev->sd_desc->querymenu)
 936                 return -EINVAL;
 937         return gspca_dev->sd_desc->querymenu(gspca_dev, qmenu);
 938 }
 939
 940 static int vidioc_enum_input(struct file *file, void *priv,
 941                                 struct v4l2_input *input)
 942 {
 943         struct gspca_dev *gspca_dev = priv;
 944
 945         if (input->index != 0)
 946                 return -EINVAL;
 947         memset(input, 0, sizeof *input);
 948         input->type = V4L2_INPUT_TYPE_CAMERA;
 949         strncpy(input->name, gspca_dev->sd_desc->name,
 950                 sizeof input->name);
 951         return 0;
 952 }
 953
 954 static int vidioc_g_input(struct file *file, void *priv, unsigned int *i)
 955 {
 956         *i = 0;
 957         return 0;
 958 }
 959
 960 static int vidioc_s_input(struct file *file, void *priv, unsigned int i)
 961 {
 962         if (i > 0)
 963                 return -EINVAL;
 964         return (0);
 965 }
 966
 967 static int vidioc_reqbufs(struct file *file, void *priv,
 968                           struct v4l2_requestbuffers *rb)
 969 {
 970         struct gspca_dev *gspca_dev = priv;
 971         int i, ret = 0;
 972
 973         if (rb->type != V4L2_BUF_TYPE_VIDEO_CAPTURE)
 974                 return -EINVAL;
 975         switch (rb->memory) {
 976         case GSPCA_MEMORY_READ:                 /* (internal call) */
 977         case V4L2_MEMORY_MMAP:
 978         case V4L2_MEMORY_USERPTR:
 979                 break;
 980         default:
 981                 return -EINVAL;
 982         }
 983         if (mutex_lock_interruptible(&gspca_dev->queue_lock))
 984                 return -ERESTARTSYS;
 985
 986         if (gspca_dev->memory != GSPCA_MEMORY_NO
 987             && gspca_dev->memory != rb->memory) {
 988                 ret = -EBUSY;
 989                 goto out;
 990         }
 991
 992         /* only one file may do the capture */
 993         if (gspca_dev->capt_file != NULL
 994             && gspca_dev->capt_file != file) {
 995                 ret = -EBUSY;
 996                 goto out;
 997         }
 998
 999         /* if allocated, the buffers must not be mapped */
1000         for (i = 0; i < gspca_dev->nframes; i++) {
1001                 if (gspca_dev->frame[i].vma_use_count) {
1002                         ret = -EBUSY;
1003                         goto out;
1004                 }
1005         }
1006
1007         /* stop streaming */
1008         if (gspca_dev->streaming) {
1009                 mutex_lock(&gspca_dev->usb_lock);
1010                 gspca_stream_off(gspca_dev);
1011                 mutex_unlock(&gspca_dev->usb_lock);
1012         }
1013
1014         /* free the previous allocated buffers, if any */
1015         if (gspca_dev->nframes != 0) {
1016                 frame_free(gspca_dev);
1017                 gspca_dev->capt_file = NULL;
1018         }
1019         if (rb->count == 0)                     /* unrequest */
1020                 goto out;
1021         gspca_dev->memory = rb->memory;
1022         ret = frame_alloc(gspca_dev, rb->count);
1023         if (ret == 0) {
1024                 rb->count = gspca_dev->nframes;
1025                 gspca_dev->capt_file = file;
1026         }
1027 out:
1028         mutex_unlock(&gspca_dev->queue_lock);
1029         PDEBUG(D_STREAM, "reqbufs st:%d c:%d", ret, rb->count);
1030         return ret;
1031 }
1032
1033 static int vidioc_querybuf(struct file *file, void *priv,
1034                            struct v4l2_buffer *v4l2_buf)
1035 {
1036         struct gspca_dev *gspca_dev = priv;
1037         struct gspca_frame *frame;
1038
1039         if (v4l2_buf->type != V4L2_BUF_TYPE_VIDEO_CAPTURE
1040             || v4l2_buf->index < 0
1041             || v4l2_buf->index >= gspca_dev->nframes)
1042                 return -EINVAL;
1043
1044         frame = &gspca_dev->frame[v4l2_buf->index];
1045         memcpy(v4l2_buf, &frame->v4l2_buf, sizeof *v4l2_buf);
1046         return 0;
1047 }
1048
1049 static int vidioc_streamon(struct file *file, void *priv,
1050                            enum v4l2_buf_type buf_type)
1051 {
1052         struct gspca_dev *gspca_dev = priv;
1053         int ret;
1054
1055         if (buf_type != V4L2_BUF_TYPE_VIDEO_CAPTURE)
1056                 return -EINVAL;
1057         if (mutex_lock_interruptible(&gspca_dev->queue_lock))
1058                 return -ERESTARTSYS;
1059         if (!gspca_dev->present) {
1060                 ret = -ENODEV;
1061                 goto out;
1062         }
1063         if (gspca_dev->nframes == 0) {
1064                 ret = -EINVAL;
1065                 goto out;
1066         }
1067         if (!gspca_dev->streaming) {
1068                 ret = gspca_init_transfer(gspca_dev);
1069                 if (ret < 0)
1070                         goto out;
1071         }
1072 #ifdef CONFIG_VIDEO_ADV_DEBUG
1073         if (gspca_debug & D_STREAM) {
1074                 PDEBUG_MODE("stream on OK",
1075                         gspca_dev->pixfmt,
1076                         gspca_dev->width,
1077                         gspca_dev->height);
1078         }
1079 #endif
1080         ret = 0;
1081 out:
1082         mutex_unlock(&gspca_dev->queue_lock);
1083         return ret;
1084 }
1085
1086 static int vidioc_streamoff(struct file *file, void *priv,
1087                                 enum v4l2_buf_type buf_type)
1088 {
1089         struct gspca_dev *gspca_dev = priv;
1090         int i, ret;
1091
1092         if (buf_type != V4L2_BUF_TYPE_VIDEO_CAPTURE)
1093                 return -EINVAL;
1094         if (!gspca_dev->streaming)
1095                 return 0;
1096         if (mutex_lock_interruptible(&gspca_dev->queue_lock))
1097                 return -ERESTARTSYS;
1098
1099         /* stop streaming */
1100         if (mutex_lock_interruptible(&gspca_dev->usb_lock)) {
1101                 ret = -ERESTARTSYS;
1102                 goto out;
1103         }
1104         gspca_stream_off(gspca_dev);
1105         mutex_unlock(&gspca_dev->usb_lock);
1106
1107         /* empty the application queues */
1108         for (i = 0; i < gspca_dev->nframes; i++)
1109                 gspca_dev->frame[i].v4l2_buf.flags &= ~BUF_ALL_FLAGS;
1110         gspca_dev->fr_i = gspca_dev->fr_o = gspca_dev->fr_q = 0;
1111         gspca_dev->last_packet_type = DISCARD_PACKET;
1112         gspca_dev->sequence = 0;
1113         atomic_set(&gspca_dev->nevent, 0);
1114         ret = 0;
1115 out:
1116         mutex_unlock(&gspca_dev->queue_lock);
1117         return ret;
1118 }
1119
1120 static int vidioc_g_jpegcomp(struct file *file, void *priv,
1121                         struct v4l2_jpegcompression *jpegcomp)
1122 {
1123         struct gspca_dev *gspca_dev = priv;
1124         int ret;
1125
1126         if (!gspca_dev->sd_desc->get_jcomp)
1127                 return -EINVAL;
1128         if (mutex_lock_interruptible(&gspca_dev->usb_lock))
1129                 return -ERESTARTSYS;
1130         ret = gspca_dev->sd_desc->get_jcomp(gspca_dev, jpegcomp);
1131         mutex_unlock(&gspca_dev->usb_lock);
1132         return ret;
1133 }
1134
1135 static int vidioc_s_jpegcomp(struct file *file, void *priv,
1136                         struct v4l2_jpegcompression *jpegcomp)
1137 {
1138         struct gspca_dev *gspca_dev = priv;
1139         int ret;
1140
1141         if (mutex_lock_interruptible(&gspca_dev->usb_lock))
1142                 return -ERESTARTSYS;
1143         if (!gspca_dev->sd_desc->set_jcomp)
1144                 return -EINVAL;
1145         ret = gspca_dev->sd_desc->set_jcomp(gspca_dev, jpegcomp);
1146         mutex_unlock(&gspca_dev->usb_lock);
1147         return ret;
1148 }
1149
1150 static int vidioc_g_parm(struct file *filp, void *priv,
1151                         struct v4l2_streamparm *parm)
1152 {
1153         struct gspca_dev *gspca_dev = priv;
1154
1155         memset(parm, 0, sizeof *parm);
1156         parm->type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
1157         parm->parm.capture.readbuffers = gspca_dev->nbufread;
1158         return 0;
1159 }
1160
1161 static int vidioc_s_parm(struct file *filp, void *priv,
1162                         struct v4l2_streamparm *parm)
1163 {
1164         struct gspca_dev *gspca_dev = priv;
1165         int n;
1166
1167         n = parm->parm.capture.readbuffers;
1168         if (n == 0 || n > GSPCA_MAX_FRAMES)
1169                 parm->parm.capture.readbuffers = gspca_dev->nbufread;
1170         else
1171                 gspca_dev->nbufread = n;
1172         return 0;
1173 }
1174
1175 static int vidioc_s_std(struct file *filp, void *priv,
1176                         v4l2_std_id *parm)
1177 {
1178         return 0;
1179 }
1180
1181 #ifdef CONFIG_VIDEO_V4L1_COMPAT
1182 static int vidiocgmbuf(struct file *file, void *priv,
1183                         struct video_mbuf *mbuf)
1184 {
1185         struct gspca_dev *gspca_dev = file->private_data;
1186         int i;
1187
1188         PDEBUG(D_STREAM, "cgmbuf");
1189         if (gspca_dev->nframes == 0) {
1190                 int ret;
1191
1192                 {
1193                         struct v4l2_format fmt;
1194
1195                         memset(&fmt, 0, sizeof fmt);
1196                         fmt.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
1197                         i = gspca_dev->cam.nmodes - 1;  /* highest mode */
1198                         fmt.fmt.pix.width = gspca_dev->cam.cam_mode[i].width;
1199                         fmt.fmt.pix.height = gspca_dev->cam.cam_mode[i].height;
1200                         fmt.fmt.pix.pixelformat = V4L2_PIX_FMT_BGR24;
1201                         ret = vidioc_s_fmt_vid_cap(file, priv, &fmt);
1202                         if (ret != 0)
1203                                 return ret;
1204                 }
1205                 {
1206                         struct v4l2_requestbuffers rb;
1207
1208                         memset(&rb, 0, sizeof rb);
1209                         rb.count = 4;
1210                         rb.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
1211                         rb.memory = V4L2_MEMORY_MMAP;
1212                         ret = vidioc_reqbufs(file, priv, &rb);
1213                         if (ret != 0)
1214                                 return ret;
1215                 }
1216         }
1217         mbuf->frames = gspca_dev->nframes;
1218         mbuf->size = gspca_dev->frsz * gspca_dev->nframes;
1219         for (i = 0; i < mbuf->frames; i++)
1220                 mbuf->offsets[i] = gspca_dev->frame[i].v4l2_buf.m.offset;
1221         return 0;
1222 }
1223 #endif
1224
1225 static int dev_mmap(struct file *file, struct vm_area_struct *vma)
1226 {
1227         struct gspca_dev *gspca_dev = file->private_data;
1228         struct gspca_frame *frame;
1229         struct page *page;
1230         unsigned long addr, start, size;
1231         int i, ret;
1232
1233         start = vma->vm_start;
1234         size = vma->vm_end - vma->vm_start;
1235         PDEBUG(D_STREAM, "mmap start:%08x size:%d", (int) start, (int) size);
1236
1237         if (mutex_lock_interruptible(&gspca_dev->queue_lock))
1238                 return -ERESTARTSYS;
1239         if (!gspca_dev->present) {
1240                 ret = -ENODEV;
1241                 goto out;
1242         }
1243         if (gspca_dev->capt_file != file) {
1244                 ret = -EINVAL;
1245                 goto out;
1246         }
1247
1248         frame = NULL;
1249         for (i = 0; i < gspca_dev->nframes; ++i) {
1250                 if (gspca_dev->frame[i].v4l2_buf.memory != V4L2_MEMORY_MMAP) {
1251                         PDEBUG(D_STREAM, "mmap bad memory type");
1252                         break;
1253                 }
1254                 if ((gspca_dev->frame[i].v4l2_buf.m.offset >> PAGE_SHIFT)
1255                                                 == vma->vm_pgoff) {
1256                         frame = &gspca_dev->frame[i];
1257                         break;
1258                 }
1259         }
1260         if (frame == NULL) {
1261                 PDEBUG(D_STREAM, "mmap no frame buffer found");
1262                 ret = -EINVAL;
1263                 goto out;
1264         }
1265 #ifdef CONFIG_VIDEO_V4L1_COMPAT
1266         /* v4l1 maps all the buffers */
1267         if (i != 0
1268             || size != frame->v4l2_buf.length * gspca_dev->nframes)
1269 #endif
1270             if (size != frame->v4l2_buf.length) {
1271                 PDEBUG(D_STREAM, "mmap bad size");
1272                 ret = -EINVAL;
1273                 goto out;
1274         }
1275
1276         /*
1277          * - VM_IO marks the area as being a mmaped region for I/O to a
1278          *   device. It also prevents the region from being core dumped.
1279          */
1280         vma->vm_flags |= VM_IO;
1281
1282         addr = (unsigned long) frame->data;
1283         while (size > 0) {
1284                 page = vmalloc_to_page((void *) addr);
1285                 ret = vm_insert_page(vma, start, page);
1286                 if (ret < 0)
1287                         goto out;
1288                 start += PAGE_SIZE;
1289                 addr += PAGE_SIZE;
1290                 size -= PAGE_SIZE;
1291         }
1292
1293         vma->vm_ops = &gspca_vm_ops;
1294         vma->vm_private_data = frame;
1295         gspca_vm_open(vma);
1296         ret = 0;
1297 out:
1298         mutex_unlock(&gspca_dev->queue_lock);
1299         return ret;
1300 }
1301
1302 /*
1303  * wait for a video frame
1304  *
1305  * If a frame is ready, its index is returned.
1306  */
1307 static int frame_wait(struct gspca_dev *gspca_dev,
1308                         int nonblock_ing)
1309 {
1310         struct gspca_frame *frame;
1311         int i, j, ret;
1312
1313         /* check if a frame is ready */
1314         i = gspca_dev->fr_o;
1315         j = gspca_dev->fr_queue[i];
1316         frame = &gspca_dev->frame[j];
1317         if (frame->v4l2_buf.flags & V4L2_BUF_FLAG_DONE) {
1318                 atomic_dec(&gspca_dev->nevent);
1319                 goto ok;
1320         }
1321         if (nonblock_ing)                       /* no frame yet */
1322                 return -EAGAIN;
1323
1324         /* wait till a frame is ready */
1325         for (;;) {
1326                 ret = wait_event_interruptible_timeout(gspca_dev->wq,
1327                                         atomic_read(&gspca_dev->nevent) > 0,
1328                                         msecs_to_jiffies(3000));
1329                 if (ret <= 0) {
1330                         if (ret < 0)
1331                                 return ret;     /* interrupt */
1332                         return -EIO;            /* timeout */
1333                 }
1334                 atomic_dec(&gspca_dev->nevent);
1335                 if (!gspca_dev->streaming || !gspca_dev->present)
1336                         return -EIO;
1337                 i = gspca_dev->fr_o;
1338                 j = gspca_dev->fr_queue[i];
1339                 frame = &gspca_dev->frame[j];
1340                 if (frame->v4l2_buf.flags & V4L2_BUF_FLAG_DONE)
1341                         break;
1342         }
1343 ok:
1344         gspca_dev->fr_o = (i + 1) % gspca_dev->nframes;
1345         PDEBUG(D_FRAM, "frame wait q:%d i:%d o:%d",
1346                 gspca_dev->fr_q,
1347                 gspca_dev->fr_i,
1348                 gspca_dev->fr_o);
1349
1350         if (gspca_dev->sd_desc->dq_callback) {
1351                 mutex_lock(&gspca_dev->usb_lock);
1352                 gspca_dev->sd_desc->dq_callback(gspca_dev);
1353                 mutex_unlock(&gspca_dev->usb_lock);
1354         }
1355         return j;
1356 }
1357
1358 /*
1359  * dequeue a video buffer
1360  *
1361  * If nonblock_ing is false, block until a buffer is available.
1362  */
1363 static int vidioc_dqbuf(struct file *file, void *priv,
1364                         struct v4l2_buffer *v4l2_buf)
1365 {
1366         struct gspca_dev *gspca_dev = priv;
1367         struct gspca_frame *frame;
1368         int i, ret;
1369
1370         PDEBUG(D_FRAM, "dqbuf");
1371         if (v4l2_buf->type != V4L2_BUF_TYPE_VIDEO_CAPTURE)
1372                 return -EINVAL;
1373         if (v4l2_buf->memory != gspca_dev->memory)
1374                 return -EINVAL;
1375
1376         /* if not streaming, be sure the application will not loop forever */
1377         if (!(file->f_flags & O_NONBLOCK)
1378             && !gspca_dev->streaming && gspca_dev->users == 1)
1379                 return -EINVAL;
1380
1381         /* only the capturing file may dequeue */
1382         if (gspca_dev->capt_file != file)
1383                 return -EINVAL;
1384
1385         /* only one dequeue / read at a time */
1386         if (mutex_lock_interruptible(&gspca_dev->read_lock))
1387                 return -ERESTARTSYS;
1388
1389         ret = frame_wait(gspca_dev, file->f_flags & O_NONBLOCK);
1390         if (ret < 0)
1391                 goto out;
1392         i = ret;                                /* frame index */
1393         frame = &gspca_dev->frame[i];
1394         if (gspca_dev->memory == V4L2_MEMORY_USERPTR) {
1395                 if (copy_to_user((__u8 *) frame->v4l2_buf.m.userptr,
1396                                  frame->data,
1397                                  frame->v4l2_buf.bytesused)) {
1398                         PDEBUG(D_ERR|D_STREAM,
1399                                 "dqbuf cp to user failed");
1400                         ret = -EFAULT;
1401                         goto out;
1402                 }
1403         }
1404         frame->v4l2_buf.flags &= ~V4L2_BUF_FLAG_DONE;
1405         memcpy(v4l2_buf, &frame->v4l2_buf, sizeof *v4l2_buf);
1406         PDEBUG(D_FRAM, "dqbuf %d", i);
1407         ret = 0;
1408 out:
1409         mutex_unlock(&gspca_dev->read_lock);
1410         return ret;
1411 }
1412
1413 /*
1414  * queue a video buffer
1415  *
1416  * Attempting to queue a buffer that has already been
1417  * queued will return -EINVAL.
1418  */
1419 static int vidioc_qbuf(struct file *file, void *priv,
1420                         struct v4l2_buffer *v4l2_buf)
1421 {
1422         struct gspca_dev *gspca_dev = priv;
1423         struct gspca_frame *frame;
1424         int i, index, ret;
1425
1426         PDEBUG(D_FRAM, "qbuf %d", v4l2_buf->index);
1427         if (v4l2_buf->type != V4L2_BUF_TYPE_VIDEO_CAPTURE)
1428                 return -EINVAL;
1429
1430         if (mutex_lock_interruptible(&gspca_dev->queue_lock))
1431                 return -ERESTARTSYS;
1432
1433         index = v4l2_buf->index;
1434         if ((unsigned) index >= gspca_dev->nframes) {
1435                 PDEBUG(D_FRAM,
1436                         "qbuf idx %d >= %d", index, gspca_dev->nframes);
1437                 ret = -EINVAL;
1438                 goto out;
1439         }
1440         if (v4l2_buf->memory != gspca_dev->memory) {
1441                 PDEBUG(D_FRAM, "qbuf bad memory type");
1442                 ret = -EINVAL;
1443                 goto out;
1444         }
1445
1446         frame = &gspca_dev->frame[index];
1447         if (frame->v4l2_buf.flags & BUF_ALL_FLAGS) {
1448                 PDEBUG(D_FRAM, "qbuf bad state");
1449                 ret = -EINVAL;
1450                 goto out;
1451         }
1452
1453         frame->v4l2_buf.flags |= V4L2_BUF_FLAG_QUEUED;
1454 /*      frame->v4l2_buf.flags &= ~V4L2_BUF_FLAG_DONE; */
1455
1456         if (frame->v4l2_buf.memory == V4L2_MEMORY_USERPTR) {
1457                 frame->v4l2_buf.m.userptr = v4l2_buf->m.userptr;
1458                 frame->v4l2_buf.length = v4l2_buf->length;
1459         }
1460
1461         /* put the buffer in the 'queued' queue */
1462         i = gspca_dev->fr_q;
1463         gspca_dev->fr_queue[i] = index;
1464         gspca_dev->fr_q = (i + 1) % gspca_dev->nframes;
1465         PDEBUG(D_FRAM, "qbuf q:%d i:%d o:%d",
1466                 gspca_dev->fr_q,
1467                 gspca_dev->fr_i,
1468                 gspca_dev->fr_o);
1469
1470         v4l2_buf->flags |= V4L2_BUF_FLAG_QUEUED;
1471         v4l2_buf->flags &= ~V4L2_BUF_FLAG_DONE;
1472         ret = 0;
1473 out:
1474         mutex_unlock(&gspca_dev->queue_lock);
1475         return ret;
1476 }
1477
1478 /*
1479  * allocate the resources for read()
1480  */
1481 static int read_alloc(struct gspca_dev *gspca_dev,
1482                         struct file *file)
1483 {
1484         struct v4l2_buffer v4l2_buf;
1485         int i, ret;
1486
1487         PDEBUG(D_STREAM, "read alloc");
1488         if (gspca_dev->nframes == 0) {
1489                 struct v4l2_requestbuffers rb;
1490
1491                 memset(&rb, 0, sizeof rb);
1492                 rb.count = gspca_dev->nbufread;
1493                 rb.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
1494                 rb.memory = GSPCA_MEMORY_READ;
1495                 ret = vidioc_reqbufs(file, gspca_dev, &rb);
1496                 if (ret != 0) {
1497                         PDEBUG(D_STREAM, "read reqbuf err %d", ret);
1498                         return ret;
1499                 }
1500                 memset(&v4l2_buf, 0, sizeof v4l2_buf);
1501                 v4l2_buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
1502                 v4l2_buf.memory = GSPCA_MEMORY_READ;
1503                 for (i = 0; i < gspca_dev->nbufread; i++) {
1504                         v4l2_buf.index = i;
1505                         ret = vidioc_qbuf(file, gspca_dev, &v4l2_buf);
1506                         if (ret != 0) {
1507                                 PDEBUG(D_STREAM, "read qbuf err: %d", ret);
1508                                 return ret;
1509                         }
1510                 }
1511                 gspca_dev->memory = GSPCA_MEMORY_READ;
1512         }
1513
1514         /* start streaming */
1515         ret = vidioc_streamon(file, gspca_dev, V4L2_BUF_TYPE_VIDEO_CAPTURE);
1516         if (ret != 0)
1517                 PDEBUG(D_STREAM, "read streamon err %d", ret);
1518         return ret;
1519 }
1520
1521 static unsigned int dev_poll(struct file *file, poll_table *wait)
1522 {
1523         struct gspca_dev *gspca_dev = file->private_data;
1524         int i, ret;
1525
1526         PDEBUG(D_FRAM, "poll");
1527
1528         poll_wait(file, &gspca_dev->wq, wait);
1529         if (!gspca_dev->present)
1530                 return POLLERR;
1531
1532         /* if reqbufs is not done, the user would use read() */
1533         if (gspca_dev->nframes == 0) {
1534                 if (gspca_dev->memory != GSPCA_MEMORY_NO)
1535                         return POLLERR;         /* not the 1st time */
1536                 ret = read_alloc(gspca_dev, file);
1537                 if (ret != 0)
1538                         return POLLERR;
1539         }
1540
1541         if (mutex_lock_interruptible(&gspca_dev->queue_lock) != 0)
1542                 return POLLERR;
1543         if (!gspca_dev->present) {
1544                 ret = POLLERR;
1545                 goto out;
1546         }
1547
1548         /* check the next incoming buffer */
1549         i = gspca_dev->fr_o;
1550         i = gspca_dev->fr_queue[i];
1551         if (gspca_dev->frame[i].v4l2_buf.flags & V4L2_BUF_FLAG_DONE)
1552                 ret = POLLIN | POLLRDNORM;      /* something to read */
1553         else
1554                 ret = 0;
1555 out:
1556         mutex_unlock(&gspca_dev->queue_lock);
1557         return ret;
1558 }
1559
1560 static ssize_t dev_read(struct file *file, char __user *data,
1561                     size_t count, loff_t *ppos)
1562 {
1563         struct gspca_dev *gspca_dev = file->private_data;
1564         struct gspca_frame *frame;
1565         struct v4l2_buffer v4l2_buf;
1566         struct timeval timestamp;
1567         int n, ret, ret2;
1568
1569         PDEBUG(D_FRAM, "read (%zd)", count);
1570         if (!gspca_dev->present)
1571                 return -ENODEV;
1572         switch (gspca_dev->memory) {
1573         case GSPCA_MEMORY_NO:                   /* first time */
1574                 ret = read_alloc(gspca_dev, file);
1575                 if (ret != 0)
1576                         return ret;
1577                 break;
1578         case GSPCA_MEMORY_READ:
1579                 if (gspca_dev->capt_file == file)
1580                         break;
1581                 /* fall thru */
1582         default:
1583                 return -EINVAL;
1584         }
1585
1586         /* get a frame */
1587         jiffies_to_timeval(get_jiffies_64(), &timestamp);
1588         timestamp.tv_sec--;
1589         n = 2;
1590         for (;;) {
1591                 memset(&v4l2_buf, 0, sizeof v4l2_buf);
1592                 v4l2_buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
1593                 v4l2_buf.memory = GSPCA_MEMORY_READ;
1594                 ret = vidioc_dqbuf(file, gspca_dev, &v4l2_buf);
1595                 if (ret != 0) {
1596                         PDEBUG(D_STREAM, "read dqbuf err %d", ret);
1597                         return ret;
1598                 }
1599
1600                 /* if the process slept for more than 1 second,
1601                  * get anewer frame */
1602                 frame = &gspca_dev->frame[v4l2_buf.index];
1603                 if (--n < 0)
1604                         break;                  /* avoid infinite loop */
1605                 if (frame->v4l2_buf.timestamp.tv_sec >= timestamp.tv_sec)
1606                         break;
1607                 ret = vidioc_qbuf(file, gspca_dev, &v4l2_buf);
1608                 if (ret != 0) {
1609                         PDEBUG(D_STREAM, "read qbuf err %d", ret);
1610                         return ret;
1611                 }
1612         }
1613
1614         /* copy the frame */
1615         if (count > frame->v4l2_buf.bytesused)
1616                 count = frame->v4l2_buf.bytesused;
1617         ret = copy_to_user(data, frame->data, count);
1618         if (ret != 0) {
1619                 PDEBUG(D_ERR|D_STREAM,
1620                         "read cp to user lack %d / %zd", ret, count);
1621                 ret = -EFAULT;
1622                 goto out;
1623         }
1624         ret = count;
1625 out:
1626         /* in each case, requeue the buffer */
1627         ret2 = vidioc_qbuf(file, gspca_dev, &v4l2_buf);
1628         if (ret2 != 0)
1629                 return ret2;
1630         return ret;
1631 }
1632
1633 static void dev_release(struct video_device *vfd)
1634 {
1635         /* nothing */
1636 }
1637
1638 static struct file_operations dev_fops = {
1639         .owner = THIS_MODULE,
1640         .open = dev_open,
1641         .release = dev_close,
1642         .read = dev_read,
1643         .mmap = dev_mmap,
1644         .ioctl = video_ioctl2,
1645 #ifdef CONFIG_COMPAT
1646         .compat_ioctl = v4l_compat_ioctl32,
1647 #endif
1648         .llseek = no_llseek,
1649         .poll   = dev_poll,
1650 };
1651
1652 static struct video_device gspca_template = {
1653         .name = "gspca main driver",
1654         .type = VID_TYPE_CAPTURE,
1655         .fops = &dev_fops,
1656         .release = dev_release,         /* mandatory */
1657         .minor = -1,
1658         .vidioc_querycap        = vidioc_querycap,
1659         .vidioc_dqbuf           = vidioc_dqbuf,
1660         .vidioc_qbuf            = vidioc_qbuf,
1661         .vidioc_enum_fmt_vid_cap = vidioc_enum_fmt_vid_cap,
1662         .vidioc_try_fmt_vid_cap = vidioc_try_fmt_vid_cap,
1663         .vidioc_g_fmt_vid_cap   = vidioc_g_fmt_vid_cap,
1664         .vidioc_s_fmt_vid_cap   = vidioc_s_fmt_vid_cap,
1665         .vidioc_streamon        = vidioc_streamon,
1666         .vidioc_queryctrl       = vidioc_queryctrl,
1667         .vidioc_g_ctrl          = vidioc_g_ctrl,
1668         .vidioc_s_ctrl          = vidioc_s_ctrl,
1669         .vidioc_querymenu       = vidioc_querymenu,
1670         .vidioc_enum_input      = vidioc_enum_input,
1671         .vidioc_g_input         = vidioc_g_input,
1672         .vidioc_s_input         = vidioc_s_input,
1673         .vidioc_reqbufs         = vidioc_reqbufs,
1674         .vidioc_querybuf        = vidioc_querybuf,
1675         .vidioc_streamoff       = vidioc_streamoff,
1676         .vidioc_g_jpegcomp      = vidioc_g_jpegcomp,
1677         .vidioc_s_jpegcomp      = vidioc_s_jpegcomp,
1678         .vidioc_g_parm          = vidioc_g_parm,
1679         .vidioc_s_parm          = vidioc_s_parm,
1680         .vidioc_s_std           = vidioc_s_std,
1681 #ifdef CONFIG_VIDEO_V4L1_COMPAT
1682         .vidiocgmbuf          = vidiocgmbuf,
1683 #endif
1684 };
1685
1686 /*
1687  * probe and create a new gspca device
1688  *
1689  * This function must be called by the sub-driver when it is
1690  * called for probing a new device.
1691  */
1692 int gspca_dev_probe(struct usb_interface *intf,
1693                 const struct usb_device_id *id,
1694                 const struct sd_desc *sd_desc,
1695                 int dev_size,
1696                 struct module *module)
1697 {
1698         struct usb_interface_descriptor *interface;
1699         struct gspca_dev *gspca_dev;
1700         struct usb_device *dev = interface_to_usbdev(intf);
1701         int ret;
1702
1703         PDEBUG(D_PROBE, "probing %04x:%04x", id->idVendor, id->idProduct);
1704
1705         /* we don't handle multi-config cameras */
1706         if (dev->descriptor.bNumConfigurations != 1)
1707                 return -ENODEV;
1708         interface = &intf->cur_altsetting->desc;
1709         if (interface->bInterfaceNumber > 0)
1710                 return -ENODEV;
1711
1712         /* create the device */
1713         if (dev_size < sizeof *gspca_dev)
1714                 dev_size = sizeof *gspca_dev;
1715         gspca_dev = kzalloc(dev_size, GFP_KERNEL);
1716         if (gspca_dev == NULL) {
1717                 err("couldn't kzalloc gspca struct");
1718                 return -EIO;
1719         }
1720         gspca_dev->dev = dev;
1721         gspca_dev->iface = interface->bInterfaceNumber;
1722         gspca_dev->nbalt = intf->num_altsetting;
1723         gspca_dev->sd_desc = sd_desc;
1724 /*      gspca_dev->users = 0;                   (done by kzalloc) */
1725         gspca_dev->nbufread = 2;
1726
1727         /* configure the subdriver */
1728         ret = gspca_dev->sd_desc->config(gspca_dev, id);
1729         if (ret < 0)
1730                 goto out;
1731         ret = gspca_set_alt0(gspca_dev);
1732         if (ret < 0)
1733                 goto out;
1734         gspca_set_default_mode(gspca_dev);
1735
1736         mutex_init(&gspca_dev->usb_lock);
1737         mutex_init(&gspca_dev->read_lock);
1738         mutex_init(&gspca_dev->queue_lock);
1739         init_waitqueue_head(&gspca_dev->wq);
1740
1741         /* init video stuff */
1742         memcpy(&gspca_dev->vdev, &gspca_template, sizeof gspca_template);
1743         gspca_dev->vdev.dev = &dev->dev;
1744         memcpy(&gspca_dev->fops, &dev_fops, sizeof gspca_dev->fops);
1745         gspca_dev->vdev.fops = &gspca_dev->fops;
1746         gspca_dev->fops.owner = module;         /* module protection */
1747         ret = video_register_device(&gspca_dev->vdev,
1748                                   VFL_TYPE_GRABBER,
1749                                   video_nr);
1750         if (ret < 0) {
1751                 err("video_register_device err %d", ret);
1752                 goto out;
1753         }
1754
1755         gspca_dev->present = 1;
1756         usb_set_intfdata(intf, gspca_dev);
1757         PDEBUG(D_PROBE, "probe ok");
1758         return 0;
1759 out:
1760         kfree(gspca_dev);
1761         return ret;
1762 }
1763 EXPORT_SYMBOL(gspca_dev_probe);
1764
1765 /*
1766  * USB disconnection
1767  *
1768  * This function must be called by the sub-driver
1769  * when the device disconnects, after the specific resources are freed.
1770  */
1771 void gspca_disconnect(struct usb_interface *intf)
1772 {
1773         struct gspca_dev *gspca_dev = usb_get_intfdata(intf);
1774
1775         if (!gspca_dev)
1776                 return;
1777         gspca_dev->present = 0;
1778         mutex_lock(&gspca_dev->queue_lock);
1779         mutex_lock(&gspca_dev->usb_lock);
1780         gspca_dev->streaming = 0;
1781         destroy_urbs(gspca_dev);
1782         mutex_unlock(&gspca_dev->usb_lock);
1783         mutex_unlock(&gspca_dev->queue_lock);
1784         while (gspca_dev->users != 0) {         /* wait until fully closed */
1785                 atomic_inc(&gspca_dev->nevent);
1786                 wake_up_interruptible(&gspca_dev->wq);  /* wake processes */
1787                 schedule();
1788         }
1789 /* We don't want people trying to open up the device */
1790         video_unregister_device(&gspca_dev->vdev);
1791 /* Free the memory */
1792         kfree(gspca_dev);
1793         PDEBUG(D_PROBE, "disconnect complete");
1794 }
1795 EXPORT_SYMBOL(gspca_disconnect);
1796
1797 /* -- cam driver utility functions -- */
1798
1799 /* auto gain and exposure algorithm based on the knee algorithm described here:
1800    http://ytse.tricolour.net/docs/LowLightOptimization.html
1801
1802    Returns 0 if no changes were made, 1 if the gain and or exposure settings
1803    where changed. */
1804 int gspca_auto_gain_n_exposure(struct gspca_dev *gspca_dev, int avg_lum,
1805         int desired_avg_lum, int deadzone, int gain_knee, int exposure_knee)
1806 {
1807         int i, steps, gain, orig_gain, exposure, orig_exposure, autogain;
1808         const struct ctrl *gain_ctrl = NULL;
1809         const struct ctrl *exposure_ctrl = NULL;
1810         const struct ctrl *autogain_ctrl = NULL;
1811         int retval = 0;
1812
1813         for (i = 0; i < gspca_dev->sd_desc->nctrls; i++) {
1814                 if (gspca_dev->sd_desc->ctrls[i].qctrl.id == V4L2_CID_GAIN)
1815                         gain_ctrl = &gspca_dev->sd_desc->ctrls[i];
1816                 if (gspca_dev->sd_desc->ctrls[i].qctrl.id == V4L2_CID_EXPOSURE)
1817                         exposure_ctrl = &gspca_dev->sd_desc->ctrls[i];
1818                 if (gspca_dev->sd_desc->ctrls[i].qctrl.id == V4L2_CID_AUTOGAIN)
1819                         autogain_ctrl = &gspca_dev->sd_desc->ctrls[i];
1820         }
1821         if (!gain_ctrl || !exposure_ctrl || !autogain_ctrl) {
1822                 PDEBUG(D_ERR, "Error: gspca_auto_gain_n_exposure called "
1823                         "on cam without (auto)gain/exposure");
1824                 return 0;
1825         }
1826
1827         if (gain_ctrl->get(gspca_dev, &gain) ||
1828                         exposure_ctrl->get(gspca_dev, &exposure) ||
1829                         autogain_ctrl->get(gspca_dev, &autogain) || !autogain)
1830                 return 0;
1831
1832         orig_gain = gain;
1833         orig_exposure = exposure;
1834
1835         /* If we are of a multiple of deadzone, do multiple steps to reach the
1836            desired lumination fast (with the risc of a slight overshoot) */
1837         steps = abs(desired_avg_lum - avg_lum) / deadzone;
1838
1839         PDEBUG(D_FRAM, "autogain: lum: %d, desired: %d, steps: %d\n",
1840                 avg_lum, desired_avg_lum, steps);
1841
1842         for (i = 0; i < steps; i++) {
1843                 if (avg_lum > desired_avg_lum) {
1844                         if (gain > gain_knee)
1845                                 gain--;
1846                         else if (exposure > exposure_knee)
1847                                 exposure--;
1848                         else if (gain > gain_ctrl->qctrl.default_value)
1849                                 gain--;
1850                         else if (exposure > exposure_ctrl->qctrl.minimum)
1851                                 exposure--;
1852                         else if (gain > gain_ctrl->qctrl.minimum)
1853                                 gain--;
1854                         else
1855                                 break;
1856                 } else {
1857                         if (gain < gain_ctrl->qctrl.default_value)
1858                                 gain++;
1859                         else if (exposure < exposure_knee)
1860                                 exposure++;
1861                         else if (gain < gain_knee)
1862                                 gain++;
1863                         else if (exposure < exposure_ctrl->qctrl.maximum)
1864                                 exposure++;
1865                         else if (gain < gain_ctrl->qctrl.maximum)
1866                                 gain++;
1867                         else
1868                                 break;
1869                 }
1870         }
1871
1872         if (gain != orig_gain) {
1873                 gain_ctrl->set(gspca_dev, gain);
1874                 retval = 1;
1875         }
1876         if (exposure != orig_exposure) {
1877                 exposure_ctrl->set(gspca_dev, exposure);
1878                 retval = 1;
1879         }
1880
1881         return retval;
1882 }
1883 EXPORT_SYMBOL(gspca_auto_gain_n_exposure);
1884
1885 /* -- module insert / remove -- */
1886 static int __init gspca_init(void)
1887 {
1888         info("main v%s registered", version);
1889         return 0;
1890 }
1891 static void __exit gspca_exit(void)
1892 {
1893         info("main deregistered");
1894 }
1895
1896 module_init(gspca_init);
1897 module_exit(gspca_exit);
1898
1899 #ifdef CONFIG_VIDEO_ADV_DEBUG
1900 module_param_named(debug, gspca_debug, int, 0644);
1901 MODULE_PARM_DESC(debug,
1902                 "Debug (bit) 0x01:error 0x02:probe 0x04:config"
1903                 " 0x08:stream 0x10:frame 0x20:packet 0x40:USBin 0x80:USBout"
1904                 " 0x0100: v4l2");
1905 #endif