git.oblomov.eu Git - linux-2.6/blob - drivers/media/video/vivi.c

   1 /*
   2  * Virtual Video driver - This code emulates a real video device with v4l2 api
   3  *
   4  * Copyright (c) 2006 by:
   5  *      Mauro Carvalho Chehab <mchehab--a.t--infradead.org>
   6  *      Ted Walther <ted--a.t--enumera.com>
   7  *      John Sokol <sokol--a.t--videotechnology.com>
   8  *      http://v4l.videotechnology.com/
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the BSD Licence, GNU General Public License
  12  * as published by the Free Software Foundation; either version 2 of the
  13  * License, or (at your option) any later version
  14  */
  15 #include <linux/module.h>
  16 #include <linux/delay.h>
  17 #include <linux/errno.h>
  18 #include <linux/fs.h>
  19 #include <linux/kernel.h>
  20 #include <linux/slab.h>
  21 #include <linux/mm.h>
  22 #include <linux/ioport.h>
  23 #include <linux/init.h>
  24 #include <linux/sched.h>
  25 #include <linux/pci.h>
  26 #include <linux/random.h>
  27 #include <linux/version.h>
  28 #include <linux/mutex.h>
  29 #include <linux/videodev2.h>
  30 #include <linux/dma-mapping.h>
  31 #ifdef CONFIG_VIDEO_V4L1_COMPAT
  32 /* Include V4L1 specific functions. Should be removed soon */
  33 #include <linux/videodev.h>
  34 #endif
  35 #include <linux/interrupt.h>
  36 #include <media/videobuf-vmalloc.h>
  37 #include <media/v4l2-common.h>
  38 #include <linux/kthread.h>
  39 #include <linux/highmem.h>
  40 #include <linux/freezer.h>
  41
  42 /* Wake up at about 30 fps */
  43 #define WAKE_NUMERATOR 30
  44 #define WAKE_DENOMINATOR 1001
  45 #define BUFFER_TIMEOUT     msecs_to_jiffies(500)  /* 0.5 seconds */
  46
  47 #include "font.h"
  48
  49 #define VIVI_MAJOR_VERSION 0
  50 #define VIVI_MINOR_VERSION 4
  51 #define VIVI_RELEASE 0
  52 #define VIVI_VERSION \
  53         KERNEL_VERSION(VIVI_MAJOR_VERSION, VIVI_MINOR_VERSION, VIVI_RELEASE)
  54
  55 /* Declare static vars that will be used as parameters */
  56 static unsigned int vid_limit = 16;     /* Video memory limit, in Mb */
  57 static int video_nr = -1;               /* /dev/videoN, -1 for autodetect */
  58 static int n_devs = 1;                  /* Number of virtual devices */
  59
  60 /* supported controls */
  61 static struct v4l2_queryctrl vivi_qctrl[] = {
  62         {
  63                 .id            = V4L2_CID_AUDIO_VOLUME,
  64                 .name          = "Volume",
  65                 .minimum       = 0,
  66                 .maximum       = 65535,
  67                 .step          = 65535/100,
  68                 .default_value = 65535,
  69                 .flags         = 0,
  70                 .type          = V4L2_CTRL_TYPE_INTEGER,
  71         }, {
  72                 .id            = V4L2_CID_BRIGHTNESS,
  73                 .type          = V4L2_CTRL_TYPE_INTEGER,
  74                 .name          = "Brightness",
  75                 .minimum       = 0,
  76                 .maximum       = 255,
  77                 .step          = 1,
  78                 .default_value = 127,
  79                 .flags         = 0,
  80         }, {
  81                 .id            = V4L2_CID_CONTRAST,
  82                 .type          = V4L2_CTRL_TYPE_INTEGER,
  83                 .name          = "Contrast",
  84                 .minimum       = 0,
  85                 .maximum       = 255,
  86                 .step          = 0x1,
  87                 .default_value = 0x10,
  88                 .flags         = 0,
  89         }, {
  90                 .id            = V4L2_CID_SATURATION,
  91                 .type          = V4L2_CTRL_TYPE_INTEGER,
  92                 .name          = "Saturation",
  93                 .minimum       = 0,
  94                 .maximum       = 255,
  95                 .step          = 0x1,
  96                 .default_value = 127,
  97                 .flags         = 0,
  98         }, {
  99                 .id            = V4L2_CID_HUE,
 100                 .type          = V4L2_CTRL_TYPE_INTEGER,
 101                 .name          = "Hue",
 102                 .minimum       = -128,
 103                 .maximum       = 127,
 104                 .step          = 0x1,
 105                 .default_value = 0,
 106                 .flags         = 0,
 107         }
 108 };
 109
 110 static int qctl_regs[ARRAY_SIZE(vivi_qctrl)];
 111
 112 #define dprintk(dev, level, fmt, arg...)                                \
 113         do {                                                            \
 114                 if (dev->vfd->debug >= (level))                         \
 115                         printk(KERN_DEBUG "vivi: " fmt , ## arg);       \
 116         } while (0)
 117
 118 /* ------------------------------------------------------------------
 119         Basic structures
 120    ------------------------------------------------------------------*/
 121
 122 struct vivi_fmt {
 123         char  *name;
 124         u32   fourcc;          /* v4l2 format id */
 125         int   depth;
 126 };
 127
 128 static struct vivi_fmt format = {
 129         .name     = "4:2:2, packed, YUYV",
 130         .fourcc   = V4L2_PIX_FMT_YUYV,
 131         .depth    = 16,
 132 };
 133
 134 struct sg_to_addr {
 135         int pos;
 136         struct scatterlist *sg;
 137 };
 138
 139 /* buffer for one video frame */
 140 struct vivi_buffer {
 141         /* common v4l buffer stuff -- must be first */
 142         struct videobuf_buffer vb;
 143
 144         struct vivi_fmt        *fmt;
 145 };
 146
 147 struct vivi_dmaqueue {
 148         struct list_head       active;
 149         struct list_head       queued;
 150         struct timer_list      timeout;
 151
 152         /* thread for generating video stream*/
 153         struct task_struct         *kthread;
 154         wait_queue_head_t          wq;
 155         /* Counters to control fps rate */
 156         int                        frame;
 157         int                        ini_jiffies;
 158 };
 159
 160 static LIST_HEAD(vivi_devlist);
 161
 162 struct vivi_dev {
 163         struct list_head           vivi_devlist;
 164
 165         struct mutex               lock;
 166         spinlock_t                 slock;
 167
 168         int                        users;
 169
 170         /* various device info */
 171         struct video_device        *vfd;
 172
 173         struct vivi_dmaqueue       vidq;
 174
 175         /* Several counters */
 176         int                        h, m, s, us, jiffies;
 177         char                       timestr[13];
 178
 179         int                        mv_count;    /* Controls bars movement */
 180 };
 181
 182 struct vivi_fh {
 183         struct vivi_dev            *dev;
 184
 185         /* video capture */
 186         struct vivi_fmt            *fmt;
 187         unsigned int               width, height;
 188         struct videobuf_queue      vb_vidq;
 189
 190         enum v4l2_buf_type         type;
 191 };
 192
 193 /* ------------------------------------------------------------------
 194         DMA and thread functions
 195    ------------------------------------------------------------------*/
 196
 197 /* Bars and Colors should match positions */
 198
 199 enum colors {
 200         WHITE,
 201         AMBAR,
 202         CYAN,
 203         GREEN,
 204         MAGENTA,
 205         RED,
 206         BLUE,
 207         BLACK,
 208 };
 209
 210 static u8 bars[8][3] = {
 211         /* R   G   B */
 212         {204, 204, 204},  /* white */
 213         {208, 208,   0},  /* ambar */
 214         {  0, 206, 206},  /* cyan */
 215         {  0, 239,   0},  /* green */
 216         {239,   0, 239},  /* magenta */
 217         {205,   0,   0},  /* red */
 218         {  0,   0, 255},  /* blue */
 219         {  0,   0,   0},  /* black */
 220 };
 221
 222 #define TO_Y(r, g, b) \
 223         (((16829 * r + 33039 * g + 6416 * b  + 32768) >> 16) + 16)
 224 /* RGB to  V(Cr) Color transform */
 225 #define TO_V(r, g, b) \
 226         (((28784 * r - 24103 * g - 4681 * b  + 32768) >> 16) + 128)
 227 /* RGB to  U(Cb) Color transform */
 228 #define TO_U(r, g, b) \
 229         (((-9714 * r - 19070 * g + 28784 * b + 32768) >> 16) + 128)
 230
 231 #define TSTAMP_MIN_Y 24
 232 #define TSTAMP_MAX_Y TSTAMP_MIN_Y+15
 233 #define TSTAMP_MIN_X 64
 234
 235 static void gen_line(char *basep, int inipos, int wmax,
 236                 int hmax, int line, int count, char *timestr)
 237 {
 238         int  w, i, j, y;
 239         int pos = inipos;
 240         char *p, *s;
 241         u8   chr, r, g, b, color;
 242
 243         /* We will just duplicate the second pixel at the packet */
 244         wmax /= 2;
 245
 246         /* Generate a standard color bar pattern */
 247         for (w = 0; w < wmax; w++) {
 248                 int colorpos = ((w + count) * 8/(wmax + 1)) % 8;
 249                 r = bars[colorpos][0];
 250                 g = bars[colorpos][1];
 251                 b = bars[colorpos][2];
 252
 253                 for (color = 0; color < 4; color++) {
 254                         p = basep + pos;
 255
 256                         switch (color) {
 257                         case 0:
 258                         case 2:
 259                                 *p = TO_Y(r, g, b);     /* Luma */
 260                                 break;
 261                         case 1:
 262                                 *p = TO_U(r, g, b);     /* Cb */
 263                                 break;
 264                         case 3:
 265                                 *p = TO_V(r, g, b);     /* Cr */
 266                                 break;
 267                         }
 268                         pos++;
 269                 }
 270         }
 271
 272         /* Checks if it is possible to show timestamp */
 273         if (TSTAMP_MAX_Y >= hmax)
 274                 goto end;
 275         if (TSTAMP_MIN_X + strlen(timestr) >= wmax)
 276                 goto end;
 277
 278         /* Print stream time */
 279         if (line >= TSTAMP_MIN_Y && line <= TSTAMP_MAX_Y) {
 280                 j = TSTAMP_MIN_X;
 281                 for (s = timestr; *s; s++) {
 282                         chr = rom8x16_bits[(*s-0x30)*16+line-TSTAMP_MIN_Y];
 283                         for (i = 0; i < 7; i++) {
 284                                 if (chr & 1 << (7 - i)) {
 285                                         /* Font color*/
 286                                         r = 0;
 287                                         g = 198;
 288                                         b = 0;
 289                                 } else {
 290                                         /* Background color */
 291                                         r = bars[BLACK][0];
 292                                         g = bars[BLACK][1];
 293                                         b = bars[BLACK][2];
 294                                 }
 295
 296                                 pos = inipos + j * 2;
 297                                 for (color = 0; color < 4; color++) {
 298                                         p = basep + pos;
 299
 300                                         y = TO_Y(r, g, b);
 301
 302                                         switch (color) {
 303                                         case 0:
 304                                         case 2:
 305                                                 *p = TO_Y(r, g, b); /* Luma */
 306                                                 break;
 307                                         case 1:
 308                                                 *p = TO_U(r, g, b); /* Cb */
 309                                                 break;
 310                                         case 3:
 311                                                 *p = TO_V(r, g, b); /* Cr */
 312                                                 break;
 313                                         }
 314                                         pos++;
 315                                 }
 316                                 j++;
 317                         }
 318                 }
 319         }
 320
 321 end:
 322         return;
 323 }
 324 static void vivi_fillbuff(struct vivi_dev *dev, struct vivi_buffer *buf)
 325 {
 326         int h , pos = 0;
 327         int hmax  = buf->vb.height;
 328         int wmax  = buf->vb.width;
 329         struct timeval ts;
 330         char *tmpbuf = kmalloc(wmax * 2, GFP_KERNEL);
 331         void *vbuf = videobuf_to_vmalloc(&buf->vb);
 332
 333         if (!tmpbuf)
 334                 return;
 335
 336         for (h = 0; h < hmax; h++) {
 337                 gen_line(tmpbuf, 0, wmax, hmax, h, dev->mv_count,
 338                          dev->timestr);
 339                 /* FIXME: replacing to __copy_to_user */
 340                 if (copy_to_user(vbuf + pos, tmpbuf, wmax * 2) != 0)
 341                         dprintk(dev, 2, "vivifill copy_to_user failed.\n");
 342                 pos += wmax*2;
 343         }
 344
 345         dev->mv_count++;
 346
 347         kfree(tmpbuf);
 348
 349         /* Updates stream time */
 350
 351         dev->us += jiffies_to_usecs(jiffies-dev->jiffies);
 352         dev->jiffies = jiffies;
 353         if (dev->us >= 1000000) {
 354                 dev->us -= 1000000;
 355                 dev->s++;
 356                 if (dev->s >= 60) {
 357                         dev->s -= 60;
 358                         dev->m++;
 359                         if (dev->m > 60) {
 360                                 dev->m -= 60;
 361                                 dev->h++;
 362                                 if (dev->h > 24)
 363                                         dev->h -= 24;
 364                         }
 365                 }
 366         }
 367         sprintf(dev->timestr, "%02d:%02d:%02d:%03d",
 368                         dev->h, dev->m, dev->s,  (dev->us + 500) / 1000);
 369
 370         dprintk(dev, 2, "vivifill at %s: Buffer 0x%08lx size= %d\n",
 371                         dev->timestr, (unsigned long)tmpbuf, pos);
 372
 373         /* Advice that buffer was filled */
 374         buf->vb.state = VIDEOBUF_DONE;
 375         buf->vb.field_count++;
 376         do_gettimeofday(&ts);
 377         buf->vb.ts = ts;
 378
 379         list_del(&buf->vb.queue);
 380         wake_up(&buf->vb.done);
 381 }
 382
 383 static int restart_video_queue(struct vivi_dmaqueue *dma_q);
 384
 385 static void vivi_thread_tick(struct vivi_dmaqueue  *dma_q)
 386 {
 387         struct vivi_buffer    *buf;
 388         struct vivi_dev *dev = container_of(dma_q, struct vivi_dev, vidq);
 389
 390         int bc;
 391
 392         spin_lock(&dev->slock);
 393         /* Announces videobuf that all went ok */
 394         for (bc = 0;; bc++) {
 395                 if (list_empty(&dma_q->active)) {
 396                         dprintk(dev, 1, "No active queue to serve\n");
 397                         break;
 398                 }
 399
 400                 buf = list_entry(dma_q->active.next,
 401                                  struct vivi_buffer, vb.queue);
 402
 403                 /* Nobody is waiting something to be done, just return */
 404                 if (!waitqueue_active(&buf->vb.done)) {
 405                         mod_timer(&dma_q->timeout, jiffies+BUFFER_TIMEOUT);
 406                         spin_unlock(&dev->slock);
 407                         return;
 408                 }
 409
 410                 do_gettimeofday(&buf->vb.ts);
 411                 dprintk(dev, 2, "[%p/%d] wakeup\n", buf, buf->vb. i);
 412
 413                 /* Fill buffer */
 414                 vivi_fillbuff(dev, buf);
 415
 416                 if (list_empty(&dma_q->active)) {
 417                         del_timer(&dma_q->timeout);
 418                 } else {
 419                         mod_timer(&dma_q->timeout, jiffies + BUFFER_TIMEOUT);
 420                 }
 421         }
 422         if (bc != 1)
 423                 dprintk(dev, 1, "%s: %d buffers handled (should be 1)\n",
 424                         __FUNCTION__, bc);
 425         spin_unlock(&dev->slock);
 426 }
 427
 428 #define frames_to_ms(frames)                                    \
 429         ((frames * WAKE_NUMERATOR * 1000) / WAKE_DENOMINATOR)
 430
 431 static void vivi_sleep(struct vivi_dmaqueue  *dma_q)
 432 {
 433         struct vivi_dev *dev = container_of(dma_q, struct vivi_dev, vidq);
 434         int timeout, running_time;
 435         DECLARE_WAITQUEUE(wait, current);
 436
 437         dprintk(dev, 1, "%s dma_q=0x%08lx\n", __FUNCTION__,
 438                 (unsigned long)dma_q);
 439
 440         add_wait_queue(&dma_q->wq, &wait);
 441         if (kthread_should_stop())
 442                 goto stop_task;
 443
 444         running_time = jiffies - dma_q->ini_jiffies;
 445         dma_q->frame++;
 446
 447         /* Calculate time to wake up */
 448         timeout = msecs_to_jiffies(frames_to_ms(dma_q->frame)) - running_time;
 449
 450         if (timeout > msecs_to_jiffies(frames_to_ms(2)) || timeout <= 0) {
 451                 int old = dma_q->frame;
 452                 int nframes;
 453
 454                 dma_q->frame = (jiffies_to_msecs(running_time) /
 455                                frames_to_ms(1)) + 1;
 456
 457                 timeout = msecs_to_jiffies(frames_to_ms(dma_q->frame))
 458                           - running_time;
 459
 460                 if (unlikely (timeout <= 0))
 461                         timeout = 1;
 462
 463                 nframes = (dma_q->frame > old)?
 464                                   dma_q->frame - old : old - dma_q->frame;
 465
 466                 dprintk(dev, 1, "%ld: %s %d frames. "
 467                         "Current frame is %d. Will sleep for %d jiffies\n",
 468                         jiffies,
 469                         (dma_q->frame > old)? "Underrun, losed" : "Overrun of",
 470                         nframes, dma_q->frame, timeout);
 471         } else
 472                 dprintk(dev, 1, "will sleep for %d jiffies\n", timeout);
 473
 474         vivi_thread_tick(dma_q);
 475
 476         schedule_timeout_interruptible(timeout);
 477
 478 stop_task:
 479         remove_wait_queue(&dma_q->wq, &wait);
 480         try_to_freeze();
 481 }
 482
 483 static int vivi_thread(void *data)
 484 {
 485         struct vivi_dmaqueue  *dma_q = data;
 486         struct vivi_dev *dev = container_of(dma_q, struct vivi_dev, vidq);
 487
 488         dprintk(dev, 1, "thread started\n");
 489
 490         mod_timer(&dma_q->timeout, jiffies+BUFFER_TIMEOUT);
 491         set_freezable();
 492
 493         for (;;) {
 494                 vivi_sleep(dma_q);
 495
 496                 if (kthread_should_stop())
 497                         break;
 498         }
 499         dprintk(dev, 1, "thread: exit\n");
 500         return 0;
 501 }
 502
 503 static int vivi_start_thread(struct vivi_dmaqueue  *dma_q)
 504 {
 505         struct vivi_dev *dev = container_of(dma_q, struct vivi_dev, vidq);
 506
 507         dma_q->frame = 0;
 508         dma_q->ini_jiffies = jiffies;
 509
 510         dprintk(dev, 1, "%s\n", __FUNCTION__);
 511
 512         dma_q->kthread = kthread_run(vivi_thread, dma_q, "vivi");
 513
 514         if (IS_ERR(dma_q->kthread)) {
 515                 printk(KERN_ERR "vivi: kernel_thread() failed\n");
 516                 return PTR_ERR(dma_q->kthread);
 517         }
 518         /* Wakes thread */
 519         wake_up_interruptible(&dma_q->wq);
 520
 521         dprintk(dev, 1, "returning from %s\n", __FUNCTION__);
 522         return 0;
 523 }
 524
 525 static void vivi_stop_thread(struct vivi_dmaqueue  *dma_q)
 526 {
 527         struct vivi_dev *dev = container_of(dma_q, struct vivi_dev, vidq);
 528
 529         dprintk(dev, 1, "%s\n", __FUNCTION__);
 530         /* shutdown control thread */
 531         if (dma_q->kthread) {
 532                 kthread_stop(dma_q->kthread);
 533                 dma_q->kthread = NULL;
 534         }
 535 }
 536
 537 static int restart_video_queue(struct vivi_dmaqueue *dma_q)
 538 {
 539         struct vivi_dev *dev = container_of(dma_q, struct vivi_dev, vidq);
 540         struct vivi_buffer *buf, *prev;
 541
 542         dprintk(dev, 1, "%s dma_q=0x%08lx\n", __FUNCTION__,
 543                 (unsigned long)dma_q);
 544
 545         if (!list_empty(&dma_q->active)) {
 546                 buf = list_entry(dma_q->active.next,
 547                                  struct vivi_buffer, vb.queue);
 548                 dprintk(dev, 2, "restart_queue [%p/%d]: restart dma\n",
 549                         buf, buf->vb.i);
 550
 551                 dprintk(dev, 1, "Restarting video dma\n");
 552                 vivi_stop_thread(dma_q);
 553
 554                 /* cancel all outstanding capture / vbi requests */
 555                 list_for_each_entry_safe(buf, prev, &dma_q->active, vb.queue) {
 556                         list_del(&buf->vb.queue);
 557                         buf->vb.state = VIDEOBUF_ERROR;
 558                         wake_up(&buf->vb.done);
 559                 }
 560                 mod_timer(&dma_q->timeout, jiffies+BUFFER_TIMEOUT);
 561
 562                 return 0;
 563         }
 564
 565         prev = NULL;
 566         for (;;) {
 567                 if (list_empty(&dma_q->queued))
 568                         return 0;
 569                 buf = list_entry(dma_q->queued.next,
 570                                  struct vivi_buffer, vb.queue);
 571                 if (NULL == prev) {
 572                         list_del(&buf->vb.queue);
 573                         list_add_tail(&buf->vb.queue, &dma_q->active);
 574
 575                         dprintk(dev, 1, "Restarting video dma\n");
 576                         vivi_stop_thread(dma_q);
 577                         vivi_start_thread(dma_q);
 578
 579                         buf->vb.state = VIDEOBUF_ACTIVE;
 580                         mod_timer(&dma_q->timeout, jiffies+BUFFER_TIMEOUT);
 581                         dprintk(dev, 2,
 582                                 "[%p/%d] restart_queue - first active\n",
 583                                 buf, buf->vb.i);
 584
 585                 } else if (prev->vb.width  == buf->vb.width  &&
 586                            prev->vb.height == buf->vb.height &&
 587                            prev->fmt       == buf->fmt) {
 588                         list_del(&buf->vb.queue);
 589                         list_add_tail(&buf->vb.queue, &dma_q->active);
 590                         buf->vb.state = VIDEOBUF_ACTIVE;
 591                         dprintk(dev, 2,
 592                                 "[%p/%d] restart_queue - move to active\n",
 593                                 buf, buf->vb.i);
 594                 } else {
 595                         return 0;
 596                 }
 597                 prev = buf;
 598         }
 599 }
 600
 601 static void vivi_vid_timeout(unsigned long data)
 602 {
 603         struct vivi_dev      *dev  = (struct vivi_dev *)data;
 604         struct vivi_dmaqueue *vidq = &dev->vidq;
 605         struct vivi_buffer   *buf;
 606
 607         spin_lock(&dev->slock);
 608
 609         while (!list_empty(&vidq->active)) {
 610                 buf = list_entry(vidq->active.next,
 611                                  struct vivi_buffer, vb.queue);
 612                 list_del(&buf->vb.queue);
 613                 buf->vb.state = VIDEOBUF_ERROR;
 614                 wake_up(&buf->vb.done);
 615                 printk(KERN_INFO "vivi/0: [%p/%d] timeout\n", buf, buf->vb.i);
 616         }
 617         restart_video_queue(vidq);
 618
 619         spin_unlock(&dev->slock);
 620 }
 621
 622 /* ------------------------------------------------------------------
 623         Videobuf operations
 624    ------------------------------------------------------------------*/
 625 static int
 626 buffer_setup(struct videobuf_queue *vq, unsigned int *count, unsigned int *size)
 627 {
 628         struct vivi_fh  *fh = vq->priv_data;
 629         struct vivi_dev *dev  = fh->dev;
 630
 631         *size = fh->width*fh->height*2;
 632
 633         if (0 == *count)
 634                 *count = 32;
 635
 636         while (*size * *count > vid_limit * 1024 * 1024)
 637                 (*count)--;
 638
 639         dprintk(dev, 1, "%s, count=%d, size=%d\n", __FUNCTION__,
 640                 *count, *size);
 641
 642         return 0;
 643 }
 644
 645 static void free_buffer(struct videobuf_queue *vq, struct vivi_buffer *buf)
 646 {
 647         struct vivi_fh  *fh = vq->priv_data;
 648         struct vivi_dev *dev  = fh->dev;
 649
 650         dprintk(dev, 1, "%s\n", __FUNCTION__);
 651
 652         if (in_interrupt())
 653                 BUG();
 654
 655         videobuf_waiton(&buf->vb, 0, 0);
 656         videobuf_vmalloc_free(&buf->vb);
 657         buf->vb.state = VIDEOBUF_NEEDS_INIT;
 658 }
 659
 660 #define norm_maxw() 1024
 661 #define norm_maxh() 768
 662 static int
 663 buffer_prepare(struct videobuf_queue *vq, struct videobuf_buffer *vb,
 664                                                 enum v4l2_field field)
 665 {
 666         struct vivi_fh     *fh  = vq->priv_data;
 667         struct vivi_dev    *dev = fh->dev;
 668         struct vivi_buffer *buf = container_of(vb, struct vivi_buffer, vb);
 669         int rc, init_buffer = 0;
 670
 671         dprintk(dev, 1, "%s, field=%d\n", __FUNCTION__, field);
 672
 673         BUG_ON(NULL == fh->fmt);
 674         if (fh->width  < 48 || fh->width  > norm_maxw() ||
 675             fh->height < 32 || fh->height > norm_maxh())
 676                 return -EINVAL;
 677         buf->vb.size = fh->width*fh->height*2;
 678         if (0 != buf->vb.baddr  &&  buf->vb.bsize < buf->vb.size)
 679                 return -EINVAL;
 680
 681         if (buf->fmt       != fh->fmt    ||
 682             buf->vb.width  != fh->width  ||
 683             buf->vb.height != fh->height ||
 684         buf->vb.field  != field) {
 685                 buf->fmt       = fh->fmt;
 686                 buf->vb.width  = fh->width;
 687                 buf->vb.height = fh->height;
 688                 buf->vb.field  = field;
 689                 init_buffer = 1;
 690         }
 691
 692         if (VIDEOBUF_NEEDS_INIT == buf->vb.state) {
 693                 rc = videobuf_iolock(vq, &buf->vb, NULL);
 694                 if (rc < 0)
 695                         goto fail;
 696         }
 697
 698         buf->vb.state = VIDEOBUF_PREPARED;
 699
 700         return 0;
 701
 702 fail:
 703         free_buffer(vq, buf);
 704         return rc;
 705 }
 706
 707 static void
 708 buffer_queue(struct videobuf_queue *vq, struct videobuf_buffer *vb)
 709 {
 710         struct vivi_buffer    *buf  = container_of(vb, struct vivi_buffer, vb);
 711         struct vivi_fh        *fh   = vq->priv_data;
 712         struct vivi_dev       *dev  = fh->dev;
 713         struct vivi_dmaqueue  *vidq = &dev->vidq;
 714         struct vivi_buffer    *prev;
 715
 716         if (!list_empty(&vidq->queued)) {
 717                 dprintk(dev, 1, "adding vb queue=0x%08lx\n",
 718                         (unsigned long)&buf->vb.queue);
 719                 list_add_tail(&buf->vb.queue, &vidq->queued);
 720                 buf->vb.state = VIDEOBUF_QUEUED;
 721                 dprintk(dev, 2, "[%p/%d] buffer_queue - append to queued\n",
 722                         buf, buf->vb.i);
 723         } else if (list_empty(&vidq->active)) {
 724                 list_add_tail(&buf->vb.queue, &vidq->active);
 725
 726                 buf->vb.state = VIDEOBUF_ACTIVE;
 727                 mod_timer(&vidq->timeout, jiffies+BUFFER_TIMEOUT);
 728                 dprintk(dev, 2, "[%p/%d] buffer_queue - first active\n",
 729                         buf, buf->vb.i);
 730
 731                 vivi_start_thread(vidq);
 732         } else {
 733                 prev = list_entry(vidq->active.prev,
 734                                   struct vivi_buffer, vb.queue);
 735                 if (prev->vb.width  == buf->vb.width  &&
 736                     prev->vb.height == buf->vb.height &&
 737                     prev->fmt       == buf->fmt) {
 738                         list_add_tail(&buf->vb.queue, &vidq->active);
 739                         buf->vb.state = VIDEOBUF_ACTIVE;
 740                         dprintk(dev, 2,
 741                                 "[%p/%d] buffer_queue - append to active\n",
 742                                 buf, buf->vb.i);
 743
 744                 } else {
 745                         list_add_tail(&buf->vb.queue, &vidq->queued);
 746                         buf->vb.state = VIDEOBUF_QUEUED;
 747                         dprintk(dev, 2,
 748                                 "[%p/%d] buffer_queue - first queued\n",
 749                                 buf, buf->vb.i);
 750                 }
 751         }
 752 }
 753
 754 static void buffer_release(struct videobuf_queue *vq,
 755                            struct videobuf_buffer *vb)
 756 {
 757         struct vivi_buffer   *buf  = container_of(vb, struct vivi_buffer, vb);
 758         struct vivi_fh       *fh   = vq->priv_data;
 759         struct vivi_dev      *dev  = (struct vivi_dev *)fh->dev;
 760         struct vivi_dmaqueue *vidq = &dev->vidq;
 761
 762         dprintk(dev, 1, "%s\n", __FUNCTION__);
 763
 764         vivi_stop_thread(vidq);
 765
 766         free_buffer(vq, buf);
 767 }
 768
 769 static struct videobuf_queue_ops vivi_video_qops = {
 770         .buf_setup      = buffer_setup,
 771         .buf_prepare    = buffer_prepare,
 772         .buf_queue      = buffer_queue,
 773         .buf_release    = buffer_release,
 774 };
 775
 776 /* ------------------------------------------------------------------
 777         IOCTL vidioc handling
 778    ------------------------------------------------------------------*/
 779 static int vidioc_querycap(struct file *file, void  *priv,
 780                                         struct v4l2_capability *cap)
 781 {
 782         strcpy(cap->driver, "vivi");
 783         strcpy(cap->card, "vivi");
 784         cap->version = VIVI_VERSION;
 785         cap->capabilities =     V4L2_CAP_VIDEO_CAPTURE |
 786                                 V4L2_CAP_STREAMING     |
 787                                 V4L2_CAP_READWRITE;
 788         return 0;
 789 }
 790
 791 static int vidioc_enum_fmt_cap(struct file *file, void  *priv,
 792                                         struct v4l2_fmtdesc *f)
 793 {
 794         if (f->index > 0)
 795                 return -EINVAL;
 796
 797         strlcpy(f->description, format.name, sizeof(f->description));
 798         f->pixelformat = format.fourcc;
 799         return 0;
 800 }
 801
 802 static int vidioc_g_fmt_cap(struct file *file, void *priv,
 803                                         struct v4l2_format *f)
 804 {
 805         struct vivi_fh *fh = priv;
 806
 807         f->fmt.pix.width        = fh->width;
 808         f->fmt.pix.height       = fh->height;
 809         f->fmt.pix.field        = fh->vb_vidq.field;
 810         f->fmt.pix.pixelformat  = fh->fmt->fourcc;
 811         f->fmt.pix.bytesperline =
 812                 (f->fmt.pix.width * fh->fmt->depth) >> 3;
 813         f->fmt.pix.sizeimage =
 814                 f->fmt.pix.height * f->fmt.pix.bytesperline;
 815
 816         return (0);
 817 }
 818
 819 static int vidioc_try_fmt_cap(struct file *file, void *priv,
 820                         struct v4l2_format *f)
 821 {
 822         struct vivi_fh  *fh  = priv;
 823         struct vivi_dev *dev = fh->dev;
 824         struct vivi_fmt *fmt;
 825         enum v4l2_field field;
 826         unsigned int maxw, maxh;
 827
 828         if (format.fourcc != f->fmt.pix.pixelformat) {
 829                 dprintk(dev, 1, "Fourcc format (0x%08x) invalid. "
 830                         "Driver accepts only 0x%08x\n",
 831                         f->fmt.pix.pixelformat, format.fourcc);
 832                 return -EINVAL;
 833         }
 834         fmt = &format;
 835
 836         field = f->fmt.pix.field;
 837
 838         if (field == V4L2_FIELD_ANY) {
 839                 field = V4L2_FIELD_INTERLACED;
 840         } else if (V4L2_FIELD_INTERLACED != field) {
 841                 dprintk(dev, 1, "Field type invalid.\n");
 842                 return -EINVAL;
 843         }
 844
 845         maxw  = norm_maxw();
 846         maxh  = norm_maxh();
 847
 848         f->fmt.pix.field = field;
 849         if (f->fmt.pix.height < 32)
 850                 f->fmt.pix.height = 32;
 851         if (f->fmt.pix.height > maxh)
 852                 f->fmt.pix.height = maxh;
 853         if (f->fmt.pix.width < 48)
 854                 f->fmt.pix.width = 48;
 855         if (f->fmt.pix.width > maxw)
 856                 f->fmt.pix.width = maxw;
 857         f->fmt.pix.width &= ~0x03;
 858         f->fmt.pix.bytesperline =
 859                 (f->fmt.pix.width * fmt->depth) >> 3;
 860         f->fmt.pix.sizeimage =
 861                 f->fmt.pix.height * f->fmt.pix.bytesperline;
 862
 863         return 0;
 864 }
 865
 866 /*FIXME: This seems to be generic enough to be at videodev2 */
 867 static int vidioc_s_fmt_cap(struct file *file, void *priv,
 868                                         struct v4l2_format *f)
 869 {
 870         struct vivi_fh  *fh = priv;
 871         int ret = vidioc_try_fmt_cap(file, fh, f);
 872         if (ret < 0)
 873                 return (ret);
 874
 875         fh->fmt           = &format;
 876         fh->width         = f->fmt.pix.width;
 877         fh->height        = f->fmt.pix.height;
 878         fh->vb_vidq.field = f->fmt.pix.field;
 879         fh->type          = f->type;
 880
 881         return (0);
 882 }
 883
 884 static int vidioc_reqbufs(struct file *file, void *priv,
 885                           struct v4l2_requestbuffers *p)
 886 {
 887         struct vivi_fh  *fh = priv;
 888
 889         return (videobuf_reqbufs(&fh->vb_vidq, p));
 890 }
 891
 892 static int vidioc_querybuf(struct file *file, void *priv, struct v4l2_buffer *p)
 893 {
 894         struct vivi_fh  *fh = priv;
 895
 896         return (videobuf_querybuf(&fh->vb_vidq, p));
 897 }
 898
 899 static int vidioc_qbuf(struct file *file, void *priv, struct v4l2_buffer *p)
 900 {
 901         struct vivi_fh *fh = priv;
 902
 903         return (videobuf_qbuf(&fh->vb_vidq, p));
 904 }
 905
 906 static int vidioc_dqbuf(struct file *file, void *priv, struct v4l2_buffer *p)
 907 {
 908         struct vivi_fh  *fh = priv;
 909
 910         return (videobuf_dqbuf(&fh->vb_vidq, p,
 911                                 file->f_flags & O_NONBLOCK));
 912 }
 913
 914 #ifdef CONFIG_VIDEO_V4L1_COMPAT
 915 static int vidiocgmbuf(struct file *file, void *priv, struct video_mbuf *mbuf)
 916 {
 917         struct vivi_fh  *fh = priv;
 918
 919         return videobuf_cgmbuf(&fh->vb_vidq, mbuf, 8);
 920 }
 921 #endif
 922
 923 static int vidioc_streamon(struct file *file, void *priv, enum v4l2_buf_type i)
 924 {
 925         struct vivi_fh  *fh = priv;
 926
 927         if (fh->type != V4L2_BUF_TYPE_VIDEO_CAPTURE)
 928                 return -EINVAL;
 929         if (i != fh->type)
 930                 return -EINVAL;
 931
 932         return videobuf_streamon(&fh->vb_vidq);
 933 }
 934
 935 static int vidioc_streamoff(struct file *file, void *priv, enum v4l2_buf_type i)
 936 {
 937         struct vivi_fh  *fh = priv;
 938
 939         if (fh->type != V4L2_BUF_TYPE_VIDEO_CAPTURE)
 940                 return -EINVAL;
 941         if (i != fh->type)
 942                 return -EINVAL;
 943
 944         return videobuf_streamoff(&fh->vb_vidq);
 945 }
 946
 947 static int vidioc_s_std(struct file *file, void *priv, v4l2_std_id *i)
 948 {
 949         return 0;
 950 }
 951
 952 /* only one input in this sample driver */
 953 static int vidioc_enum_input(struct file *file, void *priv,
 954                                 struct v4l2_input *inp)
 955 {
 956         if (inp->index != 0)
 957                 return -EINVAL;
 958
 959         inp->type = V4L2_INPUT_TYPE_CAMERA;
 960         inp->std = V4L2_STD_525_60;
 961         strcpy(inp->name, "Camera");
 962
 963         return (0);
 964 }
 965
 966 static int vidioc_g_input(struct file *file, void *priv, unsigned int *i)
 967 {
 968         *i = 0;
 969
 970         return (0);
 971 }
 972 static int vidioc_s_input(struct file *file, void *priv, unsigned int i)
 973 {
 974         if (i > 0)
 975                 return -EINVAL;
 976
 977         return (0);
 978 }
 979
 980         /* --- controls ---------------------------------------------- */
 981 static int vidioc_queryctrl(struct file *file, void *priv,
 982                             struct v4l2_queryctrl *qc)
 983 {
 984         int i;
 985
 986         for (i = 0; i < ARRAY_SIZE(vivi_qctrl); i++)
 987                 if (qc->id && qc->id == vivi_qctrl[i].id) {
 988                         memcpy(qc, &(vivi_qctrl[i]),
 989                                 sizeof(*qc));
 990                         return (0);
 991                 }
 992
 993         return -EINVAL;
 994 }
 995
 996 static int vidioc_g_ctrl(struct file *file, void *priv,
 997                          struct v4l2_control *ctrl)
 998 {
 999         int i;
1000
1001         for (i = 0; i < ARRAY_SIZE(vivi_qctrl); i++)
1002                 if (ctrl->id == vivi_qctrl[i].id) {
1003                         ctrl->value = qctl_regs[i];
1004                         return (0);
1005                 }
1006
1007         return -EINVAL;
1008 }
1009 static int vidioc_s_ctrl(struct file *file, void *priv,
1010                                 struct v4l2_control *ctrl)
1011 {
1012         int i;
1013
1014         for (i = 0; i < ARRAY_SIZE(vivi_qctrl); i++)
1015                 if (ctrl->id == vivi_qctrl[i].id) {
1016                         if (ctrl->value < vivi_qctrl[i].minimum
1017                             || ctrl->value > vivi_qctrl[i].maximum) {
1018                                         return (-ERANGE);
1019                                 }
1020                         qctl_regs[i] = ctrl->value;
1021                         return (0);
1022                 }
1023         return -EINVAL;
1024 }
1025
1026 /* ------------------------------------------------------------------
1027         File operations for the device
1028    ------------------------------------------------------------------*/
1029
1030 #define line_buf_size(norm) (norm_maxw(norm)*(format.depth+7)/8)
1031
1032 static int vivi_open(struct inode *inode, struct file *file)
1033 {
1034         int minor = iminor(inode);
1035         struct vivi_dev *dev;
1036         struct vivi_fh *fh;
1037         int i;
1038
1039         printk(KERN_DEBUG "vivi: open called (minor=%d)\n", minor);
1040
1041         list_for_each_entry(dev, &vivi_devlist, vivi_devlist)
1042                 if (dev->vfd->minor == minor)
1043                         goto found;
1044         return -ENODEV;
1045
1046 found:
1047         /* If more than one user, mutex should be added */
1048         dev->users++;
1049
1050         dprintk(dev, 1, "open minor=%d type=%s users=%d\n", minor,
1051                 v4l2_type_names[V4L2_BUF_TYPE_VIDEO_CAPTURE], dev->users);
1052
1053         /* allocate + initialize per filehandle data */
1054         fh = kzalloc(sizeof(*fh), GFP_KERNEL);
1055         if (NULL == fh) {
1056                 dev->users--;
1057                 return -ENOMEM;
1058         }
1059
1060         file->private_data = fh;
1061         fh->dev      = dev;
1062
1063         fh->type     = V4L2_BUF_TYPE_VIDEO_CAPTURE;
1064         fh->fmt      = &format;
1065         fh->width    = 640;
1066         fh->height   = 480;
1067
1068         /* Put all controls at a sane state */
1069         for (i = 0; i < ARRAY_SIZE(vivi_qctrl); i++)
1070                 qctl_regs[i] = vivi_qctrl[i].default_value;
1071
1072         /* Resets frame counters */
1073         dev->h = 0;
1074         dev->m = 0;
1075         dev->s = 0;
1076         dev->us = 0;
1077         dev->mv_count = 0;
1078         dev->jiffies = jiffies;
1079         sprintf(dev->timestr, "%02d:%02d:%02d:%03d",
1080                         dev->h, dev->m, dev->s, (dev->us + 500) / 1000);
1081
1082         videobuf_queue_vmalloc_init(&fh->vb_vidq, &vivi_video_qops,
1083                         NULL, &dev->slock, fh->type, V4L2_FIELD_INTERLACED,
1084                         sizeof(struct vivi_buffer), fh);
1085
1086         return 0;
1087 }
1088
1089 static ssize_t
1090 vivi_read(struct file *file, char __user *data, size_t count, loff_t *ppos)
1091 {
1092         struct vivi_fh *fh = file->private_data;
1093
1094         if (fh->type == V4L2_BUF_TYPE_VIDEO_CAPTURE) {
1095                 return videobuf_read_stream(&fh->vb_vidq, data, count, ppos, 0,
1096                                         file->f_flags & O_NONBLOCK);
1097         }
1098         return 0;
1099 }
1100
1101 static unsigned int
1102 vivi_poll(struct file *file, struct poll_table_struct *wait)
1103 {
1104         struct vivi_fh        *fh = file->private_data;
1105         struct vivi_dev       *dev = fh->dev;
1106         struct videobuf_queue *q = &fh->vb_vidq;
1107
1108         dprintk(dev, 1, "%s\n", __FUNCTION__);
1109
1110         if (V4L2_BUF_TYPE_VIDEO_CAPTURE != fh->type)
1111                 return POLLERR;
1112
1113         return videobuf_poll_stream(file, q, wait);
1114 }
1115
1116 static int vivi_close(struct inode *inode, struct file *file)
1117 {
1118         struct vivi_fh         *fh = file->private_data;
1119         struct vivi_dev *dev       = fh->dev;
1120         struct vivi_dmaqueue *vidq = &dev->vidq;
1121
1122         int minor = iminor(inode);
1123
1124         vivi_stop_thread(vidq);
1125         videobuf_stop(&fh->vb_vidq);
1126         videobuf_mmap_free(&fh->vb_vidq);
1127
1128         kfree(fh);
1129
1130         dev->users--;
1131
1132         dprintk(dev, 1, "close called (minor=%d, users=%d)\n",
1133                 minor, dev->users);
1134
1135         return 0;
1136 }
1137
1138 static int vivi_release(void)
1139 {
1140         struct vivi_dev *dev;
1141         struct list_head *list;
1142
1143         while (!list_empty(&vivi_devlist)) {
1144                 list = vivi_devlist.next;
1145                 list_del(list);
1146                 dev = list_entry(list, struct vivi_dev, vivi_devlist);
1147
1148                 if (-1 != dev->vfd->minor)
1149                         video_unregister_device(dev->vfd);
1150                 else
1151                         video_device_release(dev->vfd);
1152
1153                 kfree(dev);
1154         }
1155
1156         return 0;
1157 }
1158
1159 static int vivi_mmap(struct file *file, struct vm_area_struct *vma)
1160 {
1161         struct vivi_fh  *fh = file->private_data;
1162         struct vivi_dev *dev = fh->dev;
1163         int ret;
1164
1165         dprintk(dev, 1, "mmap called, vma=0x%08lx\n", (unsigned long)vma);
1166
1167         ret = videobuf_mmap_mapper(&fh->vb_vidq, vma);
1168
1169         dprintk(dev, 1, "vma start=0x%08lx, size=%ld, ret=%d\n",
1170                 (unsigned long)vma->vm_start,
1171                 (unsigned long)vma->vm_end-(unsigned long)vma->vm_start,
1172                 ret);
1173
1174         return ret;
1175 }
1176
1177 static const struct file_operations vivi_fops = {
1178         .owner          = THIS_MODULE,
1179         .open           = vivi_open,
1180         .release        = vivi_close,
1181         .read           = vivi_read,
1182         .poll           = vivi_poll,
1183         .ioctl          = video_ioctl2, /* V4L2 ioctl handler */
1184         .mmap           = vivi_mmap,
1185         .llseek         = no_llseek,
1186 };
1187
1188 static struct video_device vivi_template = {
1189         .name           = "vivi",
1190         .type           = VID_TYPE_CAPTURE,
1191         .fops           = &vivi_fops,
1192         .minor          = -1,
1193         .release        = video_device_release,
1194
1195         .vidioc_querycap      = vidioc_querycap,
1196         .vidioc_enum_fmt_cap  = vidioc_enum_fmt_cap,
1197         .vidioc_g_fmt_cap     = vidioc_g_fmt_cap,
1198         .vidioc_try_fmt_cap   = vidioc_try_fmt_cap,
1199         .vidioc_s_fmt_cap     = vidioc_s_fmt_cap,
1200         .vidioc_reqbufs       = vidioc_reqbufs,
1201         .vidioc_querybuf      = vidioc_querybuf,
1202         .vidioc_qbuf          = vidioc_qbuf,
1203         .vidioc_dqbuf         = vidioc_dqbuf,
1204         .vidioc_s_std         = vidioc_s_std,
1205         .vidioc_enum_input    = vidioc_enum_input,
1206         .vidioc_g_input       = vidioc_g_input,
1207         .vidioc_s_input       = vidioc_s_input,
1208         .vidioc_queryctrl     = vidioc_queryctrl,
1209         .vidioc_g_ctrl        = vidioc_g_ctrl,
1210         .vidioc_s_ctrl        = vidioc_s_ctrl,
1211         .vidioc_streamon      = vidioc_streamon,
1212         .vidioc_streamoff     = vidioc_streamoff,
1213 #ifdef CONFIG_VIDEO_V4L1_COMPAT
1214         .vidiocgmbuf          = vidiocgmbuf,
1215 #endif
1216         .tvnorms              = V4L2_STD_525_60,
1217         .current_norm         = V4L2_STD_NTSC_M,
1218 };
1219 /* -----------------------------------------------------------------
1220         Initialization and module stuff
1221    ------------------------------------------------------------------*/
1222
1223 static int __init vivi_init(void)
1224 {
1225         int ret = -ENOMEM, i;
1226         struct vivi_dev *dev;
1227         struct video_device *vfd;
1228
1229         for (i = 0; i < n_devs; i++) {
1230                 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
1231                 if (NULL == dev)
1232                         break;
1233
1234                 list_add_tail(&dev->vivi_devlist, &vivi_devlist);
1235
1236                 /* init video dma queues */
1237                 INIT_LIST_HEAD(&dev->vidq.active);
1238                 INIT_LIST_HEAD(&dev->vidq.queued);
1239                 init_waitqueue_head(&dev->vidq.wq);
1240
1241                 /* initialize locks */
1242                 mutex_init(&dev->lock);
1243                 spin_lock_init(&dev->slock);
1244
1245                 dev->vidq.timeout.function = vivi_vid_timeout;
1246                 dev->vidq.timeout.data     = (unsigned long)dev;
1247                 init_timer(&dev->vidq.timeout);
1248
1249                 vfd = video_device_alloc();
1250                 if (NULL == vfd)
1251                         break;
1252
1253                 *vfd = vivi_template;
1254
1255                 ret = video_register_device(vfd, VFL_TYPE_GRABBER, video_nr);
1256                 if (ret < 0)
1257                         break;
1258
1259                 snprintf(vfd->name, sizeof(vfd->name), "%s (%i)",
1260                          vivi_template.name, vfd->minor);
1261
1262                 if (video_nr >= 0)
1263                         video_nr++;
1264
1265                 dev->vfd = vfd;
1266         }
1267
1268         if (ret < 0) {
1269                 vivi_release();
1270                 printk(KERN_INFO "Error %d while loading vivi driver\n", ret);
1271         } else
1272                 printk(KERN_INFO "Video Technology Magazine Virtual Video "
1273                                  "Capture Board successfully loaded.\n");
1274         return ret;
1275 }
1276
1277 static void __exit vivi_exit(void)
1278 {
1279         vivi_release();
1280 }
1281
1282 module_init(vivi_init);
1283 module_exit(vivi_exit);
1284
1285 MODULE_DESCRIPTION("Video Technology Magazine Virtual Video Capture Board");
1286 MODULE_AUTHOR("Mauro Carvalho Chehab, Ted Walther and John Sokol");
1287 MODULE_LICENSE("Dual BSD/GPL");
1288
1289 module_param(video_nr, int, 0);
1290 MODULE_PARM_DESC(video_nr, "video iminor start number");
1291
1292 module_param(n_devs, int, 0);
1293 MODULE_PARM_DESC(n_devs, "number of video devices to create");
1294
1295 module_param_named(debug, vivi_template.debug, int, 0444);
1296 MODULE_PARM_DESC(debug, "activates debug info");
1297
1298 module_param(vid_limit, int, 0644);
1299 MODULE_PARM_DESC(vid_limit, "capture memory limit in megabytes");