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