drivers/media/video/cx231xx/cx231xx-vbi.c

   1 /*
   2    cx231xx_vbi.c - driver for Conexant Cx23100/101/102 USB video capture devices
   3
   4    Copyright (C) 2008 <srinivasa.deevi at conexant dot com>
   5         Based on cx88 driver
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 2 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program; if not, write to the Free Software
  19    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  20  */
  21
  22 #include <linux/init.h>
  23 #include <linux/list.h>
  24 #include <linux/module.h>
  25 #include <linux/kernel.h>
  26 #include <linux/bitmap.h>
  27 #include <linux/usb.h>
  28 #include <linux/i2c.h>
  29 #include <linux/mm.h>
  30 #include <linux/mutex.h>
  31 #include <linux/slab.h>
  32
  33 #include <media/v4l2-common.h>
  34 #include <media/v4l2-ioctl.h>
  35 #include <media/v4l2-chip-ident.h>
  36 #include <media/msp3400.h>
  37 #include <media/tuner.h>
  38
  39 #include "cx231xx.h"
  40 #include "cx231xx-vbi.h"
  41
  42 static inline void print_err_status(struct cx231xx *dev, int packet, int status)
  43 {
  44         char *errmsg = "Unknown";
  45
  46         switch (status) {
  47         case -ENOENT:
  48                 errmsg = "unlinked synchronuously";
  49                 break;
  50         case -ECONNRESET:
  51                 errmsg = "unlinked asynchronuously";
  52                 break;
  53         case -ENOSR:
  54                 errmsg = "Buffer error (overrun)";
  55                 break;
  56         case -EPIPE:
  57                 errmsg = "Stalled (device not responding)";
  58                 break;
  59         case -EOVERFLOW:
  60                 errmsg = "Babble (bad cable?)";
  61                 break;
  62         case -EPROTO:
  63                 errmsg = "Bit-stuff error (bad cable?)";
  64                 break;
  65         case -EILSEQ:
  66                 errmsg = "CRC/Timeout (could be anything)";
  67                 break;
  68         case -ETIME:
  69                 errmsg = "Device does not respond";
  70                 break;
  71         }
  72         if (packet < 0) {
  73                 cx231xx_err(DRIVER_NAME "URB status %d [%s].\n", status,
  74                             errmsg);
  75         } else {
  76                 cx231xx_err(DRIVER_NAME "URB packet %d, status %d [%s].\n",
  77                             packet, status, errmsg);
  78         }
  79 }
  80
  81 /*
  82  * Controls the isoc copy of each urb packet
  83  */
  84 static inline int cx231xx_isoc_vbi_copy(struct cx231xx *dev, struct urb *urb)
  85 {
  86         struct cx231xx_dmaqueue *dma_q = urb->context;
  87         int rc = 1;
  88         unsigned char *p_buffer;
  89         u32 bytes_parsed = 0, buffer_size = 0;
  90         u8 sav_eav = 0;
  91
  92         if (!dev)
  93                 return 0;
  94
  95         if (dev->state & DEV_DISCONNECTED)
  96                 return 0;
  97
  98         if (urb->status < 0) {
  99                 print_err_status(dev, -1, urb->status);
 100                 if (urb->status == -ENOENT)
 101                         return 0;
 102         }
 103
 104         /* get buffer pointer and length */
 105         p_buffer = urb->transfer_buffer;
 106         buffer_size = urb->actual_length;
 107
 108         if (buffer_size > 0) {
 109                 bytes_parsed = 0;
 110
 111                 if (dma_q->is_partial_line) {
 112                         /* Handle the case where we were working on a partial
 113                            line */
 114                         sav_eav = dma_q->last_sav;
 115                 } else {
 116                         /* Check for a SAV/EAV overlapping the
 117                            buffer boundary */
 118
 119                         sav_eav = cx231xx_find_boundary_SAV_EAV(p_buffer,
 120                                                           dma_q->partial_buf,
 121                                                           &bytes_parsed);
 122                 }
 123
 124                 sav_eav &= 0xF0;
 125                 /* Get the first line if we have some portion of an SAV/EAV from
 126                    the last buffer or a partial line */
 127                 if (sav_eav) {
 128                         bytes_parsed += cx231xx_get_vbi_line(dev, dma_q,
 129                                 sav_eav,                       /* SAV/EAV */
 130                                 p_buffer + bytes_parsed,       /* p_buffer */
 131                                 buffer_size - bytes_parsed);   /* buffer size */
 132                 }
 133
 134                 /* Now parse data that is completely in this buffer */
 135                 dma_q->is_partial_line = 0;
 136
 137                 while (bytes_parsed < buffer_size) {
 138                         u32 bytes_used = 0;
 139
 140                         sav_eav = cx231xx_find_next_SAV_EAV(
 141                                 p_buffer + bytes_parsed,        /* p_buffer */
 142                                 buffer_size - bytes_parsed, /* buffer size */
 143                                 &bytes_used);   /* bytes used to get SAV/EAV */
 144
 145                         bytes_parsed += bytes_used;
 146
 147                         sav_eav &= 0xF0;
 148                         if (sav_eav && (bytes_parsed < buffer_size)) {
 149                                 bytes_parsed += cx231xx_get_vbi_line(dev,
 150                                         dma_q, sav_eav, /* SAV/EAV */
 151                                         p_buffer+bytes_parsed, /* p_buffer */
 152                                         buffer_size-bytes_parsed);/*buf size*/
 153                         }
 154                 }
 155
 156                 /* Save the last four bytes of the buffer so we can
 157                 check the buffer boundary condition next time */
 158                 memcpy(dma_q->partial_buf, p_buffer + buffer_size - 4, 4);
 159                 bytes_parsed = 0;
 160         }
 161
 162         return rc;
 163 }
 164
 165 /* ------------------------------------------------------------------
 166         Vbi buf operations
 167    ------------------------------------------------------------------*/
 168
 169 static int
 170 vbi_buffer_setup(struct videobuf_queue *vq, unsigned int *count,
 171                  unsigned int *size)
 172 {
 173         struct cx231xx_fh *fh = vq->priv_data;
 174         struct cx231xx *dev = fh->dev;
 175         u32 height = 0;
 176
 177         height = ((dev->norm & V4L2_STD_625_50) ?
 178                   PAL_VBI_LINES : NTSC_VBI_LINES);
 179
 180         *size = (dev->width * height * 2 * 2);
 181         if (0 == *count)
 182                 *count = CX231XX_DEF_VBI_BUF;
 183
 184         if (*count < CX231XX_MIN_BUF)
 185                 *count = CX231XX_MIN_BUF;
 186
 187         return 0;
 188 }
 189
 190 /* This is called *without* dev->slock held; please keep it that way */
 191 static void free_buffer(struct videobuf_queue *vq, struct cx231xx_buffer *buf)
 192 {
 193         struct cx231xx_fh *fh = vq->priv_data;
 194         struct cx231xx *dev = fh->dev;
 195         unsigned long flags = 0;
 196         if (in_interrupt())
 197                 BUG();
 198
 199         /* We used to wait for the buffer to finish here, but this didn't work
 200            because, as we were keeping the state as VIDEOBUF_QUEUED,
 201            videobuf_queue_cancel marked it as finished for us.
 202            (Also, it could wedge forever if the hardware was misconfigured.)
 203
 204            This should be safe; by the time we get here, the buffer isn't
 205            queued anymore. If we ever start marking the buffers as
 206            VIDEOBUF_ACTIVE, it won't be, though.
 207          */
 208         spin_lock_irqsave(&dev->vbi_mode.slock, flags);
 209         if (dev->vbi_mode.bulk_ctl.buf == buf)
 210                 dev->vbi_mode.bulk_ctl.buf = NULL;
 211         spin_unlock_irqrestore(&dev->vbi_mode.slock, flags);
 212
 213         videobuf_vmalloc_free(&buf->vb);
 214         buf->vb.state = VIDEOBUF_NEEDS_INIT;
 215 }
 216
 217 static int
 218 vbi_buffer_prepare(struct videobuf_queue *vq, struct videobuf_buffer *vb,
 219                    enum v4l2_field field)
 220 {
 221         struct cx231xx_fh *fh = vq->priv_data;
 222         struct cx231xx_buffer *buf =
 223             container_of(vb, struct cx231xx_buffer, vb);
 224         struct cx231xx *dev = fh->dev;
 225         int rc = 0, urb_init = 0;
 226         u32 height = 0;
 227
 228         height = ((dev->norm & V4L2_STD_625_50) ?
 229                   PAL_VBI_LINES : NTSC_VBI_LINES);
 230         buf->vb.size = ((dev->width << 1) * height * 2);
 231
 232         if (0 != buf->vb.baddr && buf->vb.bsize < buf->vb.size)
 233                 return -EINVAL;
 234
 235         buf->vb.width = dev->width;
 236         buf->vb.height = height;
 237         buf->vb.field = field;
 238         buf->vb.field = V4L2_FIELD_SEQ_TB;
 239
 240         if (VIDEOBUF_NEEDS_INIT == buf->vb.state) {
 241                 rc = videobuf_iolock(vq, &buf->vb, NULL);
 242                 if (rc < 0)
 243                         goto fail;
 244         }
 245
 246         if (!dev->vbi_mode.bulk_ctl.num_bufs)
 247                 urb_init = 1;
 248
 249         if (urb_init) {
 250                 rc = cx231xx_init_vbi_isoc(dev, CX231XX_NUM_VBI_PACKETS,
 251                                            CX231XX_NUM_VBI_BUFS,
 252                                            dev->vbi_mode.alt_max_pkt_size[0],
 253                                            cx231xx_isoc_vbi_copy);
 254                 if (rc < 0)
 255                         goto fail;
 256         }
 257
 258         buf->vb.state = VIDEOBUF_PREPARED;
 259         return 0;
 260
 261 fail:
 262         free_buffer(vq, buf);
 263         return rc;
 264 }
 265
 266 static void
 267 vbi_buffer_queue(struct videobuf_queue *vq, struct videobuf_buffer *vb)
 268 {
 269         struct cx231xx_buffer *buf =
 270             container_of(vb, struct cx231xx_buffer, vb);
 271         struct cx231xx_fh *fh = vq->priv_data;
 272         struct cx231xx *dev = fh->dev;
 273         struct cx231xx_dmaqueue *vidq = &dev->vbi_mode.vidq;
 274
 275         buf->vb.state = VIDEOBUF_QUEUED;
 276         list_add_tail(&buf->vb.queue, &vidq->active);
 277
 278 }
 279
 280 static void vbi_buffer_release(struct videobuf_queue *vq,
 281                                struct videobuf_buffer *vb)
 282 {
 283         struct cx231xx_buffer *buf =
 284             container_of(vb, struct cx231xx_buffer, vb);
 285
 286
 287         free_buffer(vq, buf);
 288 }
 289
 290 struct videobuf_queue_ops cx231xx_vbi_qops = {
 291         .buf_setup   = vbi_buffer_setup,
 292         .buf_prepare = vbi_buffer_prepare,
 293         .buf_queue   = vbi_buffer_queue,
 294         .buf_release = vbi_buffer_release,
 295 };
 296
 297 /* ------------------------------------------------------------------
 298         URB control
 299    ------------------------------------------------------------------*/
 300
 301 /*
 302  * IRQ callback, called by URB callback
 303  */
 304 static void cx231xx_irq_vbi_callback(struct urb *urb)
 305 {
 306         struct cx231xx_dmaqueue *dma_q = urb->context;
 307         struct cx231xx_video_mode *vmode =
 308             container_of(dma_q, struct cx231xx_video_mode, vidq);
 309         struct cx231xx *dev = container_of(vmode, struct cx231xx, vbi_mode);
 310
 311         switch (urb->status) {
 312         case 0:         /* success */
 313         case -ETIMEDOUT:        /* NAK */
 314                 break;
 315         case -ECONNRESET:       /* kill */
 316         case -ENOENT:
 317         case -ESHUTDOWN:
 318                 return;
 319         default:                /* error */
 320                 cx231xx_err(DRIVER_NAME "urb completition error %d.\n",
 321                             urb->status);
 322                 break;
 323         }
 324
 325         /* Copy data from URB */
 326         spin_lock(&dev->vbi_mode.slock);
 327         dev->vbi_mode.bulk_ctl.bulk_copy(dev, urb);
 328         spin_unlock(&dev->vbi_mode.slock);
 329
 330         /* Reset status */
 331         urb->status = 0;
 332
 333         urb->status = usb_submit_urb(urb, GFP_ATOMIC);
 334         if (urb->status) {
 335                 cx231xx_err(DRIVER_NAME "urb resubmit failed (error=%i)\n",
 336                             urb->status);
 337         }
 338 }
 339
 340 /*
 341  * Stop and Deallocate URBs
 342  */
 343 void cx231xx_uninit_vbi_isoc(struct cx231xx *dev)
 344 {
 345         struct urb *urb;
 346         int i;
 347
 348         cx231xx_info(DRIVER_NAME "cx231xx: called cx231xx_uninit_vbi_isoc\n");
 349
 350         dev->vbi_mode.bulk_ctl.nfields = -1;
 351         for (i = 0; i < dev->vbi_mode.bulk_ctl.num_bufs; i++) {
 352                 urb = dev->vbi_mode.bulk_ctl.urb[i];
 353                 if (urb) {
 354                         if (!irqs_disabled())
 355                                 usb_kill_urb(urb);
 356                         else
 357                                 usb_unlink_urb(urb);
 358
 359                         if (dev->vbi_mode.bulk_ctl.transfer_buffer[i]) {
 360
 361                                 kfree(dev->vbi_mode.bulk_ctl.
 362                                       transfer_buffer[i]);
 363                                 dev->vbi_mode.bulk_ctl.transfer_buffer[i] =
 364                                     NULL;
 365                         }
 366                         usb_free_urb(urb);
 367                         dev->vbi_mode.bulk_ctl.urb[i] = NULL;
 368                 }
 369                 dev->vbi_mode.bulk_ctl.transfer_buffer[i] = NULL;
 370         }
 371
 372         kfree(dev->vbi_mode.bulk_ctl.urb);
 373         kfree(dev->vbi_mode.bulk_ctl.transfer_buffer);
 374
 375         dev->vbi_mode.bulk_ctl.urb = NULL;
 376         dev->vbi_mode.bulk_ctl.transfer_buffer = NULL;
 377         dev->vbi_mode.bulk_ctl.num_bufs = 0;
 378
 379         cx231xx_capture_start(dev, 0, Vbi);
 380 }
 381 EXPORT_SYMBOL_GPL(cx231xx_uninit_vbi_isoc);
 382
 383 /*
 384  * Allocate URBs and start IRQ
 385  */
 386 int cx231xx_init_vbi_isoc(struct cx231xx *dev, int max_packets,
 387                           int num_bufs, int max_pkt_size,
 388                           int (*bulk_copy) (struct cx231xx *dev,
 389                                             struct urb *urb))
 390 {
 391         struct cx231xx_dmaqueue *dma_q = &dev->vbi_mode.vidq;
 392         int i;
 393         int sb_size, pipe;
 394         struct urb *urb;
 395         int rc;
 396
 397         cx231xx_info(DRIVER_NAME "cx231xx: called cx231xx_prepare_isoc\n");
 398
 399         /* De-allocates all pending stuff */
 400         cx231xx_uninit_vbi_isoc(dev);
 401
 402         /* clear if any halt */
 403         usb_clear_halt(dev->udev,
 404                        usb_rcvbulkpipe(dev->udev,
 405                                        dev->vbi_mode.end_point_addr));
 406
 407         dev->vbi_mode.bulk_ctl.bulk_copy = bulk_copy;
 408         dev->vbi_mode.bulk_ctl.num_bufs = num_bufs;
 409         dma_q->pos = 0;
 410         dma_q->is_partial_line = 0;
 411         dma_q->last_sav = 0;
 412         dma_q->current_field = -1;
 413         dma_q->bytes_left_in_line = dev->width << 1;
 414         dma_q->lines_per_field = ((dev->norm & V4L2_STD_625_50) ?
 415                                   PAL_VBI_LINES : NTSC_VBI_LINES);
 416         dma_q->lines_completed = 0;
 417         for (i = 0; i < 8; i++)
 418                 dma_q->partial_buf[i] = 0;
 419
 420         dev->vbi_mode.bulk_ctl.urb = kzalloc(sizeof(void *) * num_bufs,
 421                                              GFP_KERNEL);
 422         if (!dev->vbi_mode.bulk_ctl.urb) {
 423                 cx231xx_errdev("cannot alloc memory for usb buffers\n");
 424                 return -ENOMEM;
 425         }
 426
 427         dev->vbi_mode.bulk_ctl.transfer_buffer =
 428             kzalloc(sizeof(void *) * num_bufs, GFP_KERNEL);
 429         if (!dev->vbi_mode.bulk_ctl.transfer_buffer) {
 430                 cx231xx_errdev("cannot allocate memory for usbtransfer\n");
 431                 kfree(dev->vbi_mode.bulk_ctl.urb);
 432                 return -ENOMEM;
 433         }
 434
 435         dev->vbi_mode.bulk_ctl.max_pkt_size = max_pkt_size;
 436         dev->vbi_mode.bulk_ctl.buf = NULL;
 437
 438         sb_size = max_packets * dev->vbi_mode.bulk_ctl.max_pkt_size;
 439
 440         /* allocate urbs and transfer buffers */
 441         for (i = 0; i < dev->vbi_mode.bulk_ctl.num_bufs; i++) {
 442
 443                 urb = usb_alloc_urb(0, GFP_KERNEL);
 444                 if (!urb) {
 445                         cx231xx_err(DRIVER_NAME
 446                                     ": cannot alloc bulk_ctl.urb %i\n", i);
 447                         cx231xx_uninit_vbi_isoc(dev);
 448                         return -ENOMEM;
 449                 }
 450                 dev->vbi_mode.bulk_ctl.urb[i] = urb;
 451                 urb->transfer_flags = URB_NO_TRANSFER_DMA_MAP;
 452
 453                 dev->vbi_mode.bulk_ctl.transfer_buffer[i] =
 454                     kzalloc(sb_size, GFP_KERNEL);
 455                 if (!dev->vbi_mode.bulk_ctl.transfer_buffer[i]) {
 456                         cx231xx_err(DRIVER_NAME
 457                                     ": unable to allocate %i bytes for transfer"
 458                                     " buffer %i%s\n", sb_size, i,
 459                                     in_interrupt() ? " while in int" : "");
 460                         cx231xx_uninit_vbi_isoc(dev);
 461                         return -ENOMEM;
 462                 }
 463
 464                 pipe = usb_rcvbulkpipe(dev->udev, dev->vbi_mode.end_point_addr);
 465                 usb_fill_bulk_urb(urb, dev->udev, pipe,
 466                                   dev->vbi_mode.bulk_ctl.transfer_buffer[i],
 467                                   sb_size, cx231xx_irq_vbi_callback, dma_q);
 468         }
 469
 470         init_waitqueue_head(&dma_q->wq);
 471
 472         /* submit urbs and enables IRQ */
 473         for (i = 0; i < dev->vbi_mode.bulk_ctl.num_bufs; i++) {
 474                 rc = usb_submit_urb(dev->vbi_mode.bulk_ctl.urb[i], GFP_ATOMIC);
 475                 if (rc) {
 476                         cx231xx_err(DRIVER_NAME
 477                                     ": submit of urb %i failed (error=%i)\n", i,
 478                                     rc);
 479                         cx231xx_uninit_vbi_isoc(dev);
 480                         return rc;
 481                 }
 482         }
 483
 484         cx231xx_capture_start(dev, 1, Vbi);
 485
 486         return 0;
 487 }
 488 EXPORT_SYMBOL_GPL(cx231xx_init_vbi_isoc);
 489
 490 u32 cx231xx_get_vbi_line(struct cx231xx *dev, struct cx231xx_dmaqueue *dma_q,
 491                          u8 sav_eav, u8 *p_buffer, u32 buffer_size)
 492 {
 493         u32 bytes_copied = 0;
 494         int current_field = -1;
 495
 496         switch (sav_eav) {
 497
 498         case SAV_VBI_FIELD1:
 499                 current_field = 1;
 500                 break;
 501
 502         case SAV_VBI_FIELD2:
 503                 current_field = 2;
 504                 break;
 505         default:
 506                 break;
 507         }
 508
 509         if (current_field < 0)
 510                 return bytes_copied;
 511
 512         dma_q->last_sav = sav_eav;
 513
 514         bytes_copied =
 515             cx231xx_copy_vbi_line(dev, dma_q, p_buffer, buffer_size,
 516                                   current_field);
 517
 518         return bytes_copied;
 519 }
 520
 521 /*
 522  * Announces that a buffer were filled and request the next
 523  */
 524 static inline void vbi_buffer_filled(struct cx231xx *dev,
 525                                      struct cx231xx_dmaqueue *dma_q,
 526                                      struct cx231xx_buffer *buf)
 527 {
 528         /* Advice that buffer was filled */
 529         /* cx231xx_info(DRIVER_NAME "[%p/%d] wakeup\n", buf, buf->vb.i); */
 530
 531         buf->vb.state = VIDEOBUF_DONE;
 532         buf->vb.field_count++;
 533         do_gettimeofday(&buf->vb.ts);
 534
 535         dev->vbi_mode.bulk_ctl.buf = NULL;
 536
 537         list_del(&buf->vb.queue);
 538         wake_up(&buf->vb.done);
 539 }
 540
 541 u32 cx231xx_copy_vbi_line(struct cx231xx *dev, struct cx231xx_dmaqueue *dma_q,
 542                           u8 *p_line, u32 length, int field_number)
 543 {
 544         u32 bytes_to_copy;
 545         struct cx231xx_buffer *buf;
 546         u32 _line_size = dev->width * 2;
 547
 548         if (dma_q->current_field == -1) {
 549                 /* Just starting up */
 550                 cx231xx_reset_vbi_buffer(dev, dma_q);
 551         }
 552
 553         if (dma_q->current_field != field_number)
 554                 dma_q->lines_completed = 0;
 555
 556         /* get the buffer pointer */
 557         buf = dev->vbi_mode.bulk_ctl.buf;
 558
 559         /* Remember the field number for next time */
 560         dma_q->current_field = field_number;
 561
 562         bytes_to_copy = dma_q->bytes_left_in_line;
 563         if (bytes_to_copy > length)
 564                 bytes_to_copy = length;
 565
 566         if (dma_q->lines_completed >= dma_q->lines_per_field) {
 567                 dma_q->bytes_left_in_line -= bytes_to_copy;
 568                 dma_q->is_partial_line =
 569                     (dma_q->bytes_left_in_line == 0) ? 0 : 1;
 570                 return 0;
 571         }
 572
 573         dma_q->is_partial_line = 1;
 574
 575         /* If we don't have a buffer, just return the number of bytes we would
 576            have copied if we had a buffer. */
 577         if (!buf) {
 578                 dma_q->bytes_left_in_line -= bytes_to_copy;
 579                 dma_q->is_partial_line =
 580                     (dma_q->bytes_left_in_line == 0) ? 0 : 1;
 581                 return bytes_to_copy;
 582         }
 583
 584         /* copy the data to video buffer */
 585         cx231xx_do_vbi_copy(dev, dma_q, p_line, bytes_to_copy);
 586
 587         dma_q->pos += bytes_to_copy;
 588         dma_q->bytes_left_in_line -= bytes_to_copy;
 589
 590         if (dma_q->bytes_left_in_line == 0) {
 591
 592                 dma_q->bytes_left_in_line = _line_size;
 593                 dma_q->lines_completed++;
 594                 dma_q->is_partial_line = 0;
 595
 596                 if (cx231xx_is_vbi_buffer_done(dev, dma_q) && buf) {
 597
 598                         vbi_buffer_filled(dev, dma_q, buf);
 599
 600                         dma_q->pos = 0;
 601                         dma_q->lines_completed = 0;
 602                         cx231xx_reset_vbi_buffer(dev, dma_q);
 603                 }
 604         }
 605
 606         return bytes_to_copy;
 607 }
 608
 609 /*
 610  * video-buf generic routine to get the next available buffer
 611  */
 612 static inline void get_next_vbi_buf(struct cx231xx_dmaqueue *dma_q,
 613                                     struct cx231xx_buffer **buf)
 614 {
 615         struct cx231xx_video_mode *vmode =
 616             container_of(dma_q, struct cx231xx_video_mode, vidq);
 617         struct cx231xx *dev = container_of(vmode, struct cx231xx, vbi_mode);
 618         char *outp;
 619
 620         if (list_empty(&dma_q->active)) {
 621                 cx231xx_err(DRIVER_NAME ": No active queue to serve\n");
 622                 dev->vbi_mode.bulk_ctl.buf = NULL;
 623                 *buf = NULL;
 624                 return;
 625         }
 626
 627         /* Get the next buffer */
 628         *buf = list_entry(dma_q->active.next, struct cx231xx_buffer, vb.queue);
 629
 630         /* Cleans up buffer - Useful for testing for frame/URB loss */
 631         outp = videobuf_to_vmalloc(&(*buf)->vb);
 632         memset(outp, 0, (*buf)->vb.size);
 633
 634         dev->vbi_mode.bulk_ctl.buf = *buf;
 635
 636         return;
 637 }
 638
 639 void cx231xx_reset_vbi_buffer(struct cx231xx *dev,
 640                               struct cx231xx_dmaqueue *dma_q)
 641 {
 642         struct cx231xx_buffer *buf;
 643
 644         buf = dev->vbi_mode.bulk_ctl.buf;
 645
 646         if (buf == NULL) {
 647                 /* first try to get the buffer */
 648                 get_next_vbi_buf(dma_q, &buf);
 649
 650                 dma_q->pos = 0;
 651                 dma_q->current_field = -1;
 652         }
 653
 654         dma_q->bytes_left_in_line = dev->width << 1;
 655         dma_q->lines_completed = 0;
 656 }
 657
 658 int cx231xx_do_vbi_copy(struct cx231xx *dev, struct cx231xx_dmaqueue *dma_q,
 659                         u8 *p_buffer, u32 bytes_to_copy)
 660 {
 661         u8 *p_out_buffer = NULL;
 662         u32 current_line_bytes_copied = 0;
 663         struct cx231xx_buffer *buf;
 664         u32 _line_size = dev->width << 1;
 665         void *startwrite;
 666         int offset, lencopy;
 667
 668         buf = dev->vbi_mode.bulk_ctl.buf;
 669
 670         if (buf == NULL)
 671                 return -EINVAL;
 672
 673         p_out_buffer = videobuf_to_vmalloc(&buf->vb);
 674
 675         if (dma_q->bytes_left_in_line != _line_size) {
 676                 current_line_bytes_copied =
 677                     _line_size - dma_q->bytes_left_in_line;
 678         }
 679
 680         offset = (dma_q->lines_completed * _line_size) +
 681                  current_line_bytes_copied;
 682
 683         if (dma_q->current_field == 2) {
 684                 /* Populate the second half of the frame */
 685                 offset += (dev->width * 2 * dma_q->lines_per_field);
 686         }
 687
 688         /* prepare destination address */
 689         startwrite = p_out_buffer + offset;
 690
 691         lencopy = dma_q->bytes_left_in_line > bytes_to_copy ?
 692                   bytes_to_copy : dma_q->bytes_left_in_line;
 693
 694         memcpy(startwrite, p_buffer, lencopy);
 695
 696         return 0;
 697 }
 698
 699 u8 cx231xx_is_vbi_buffer_done(struct cx231xx *dev,
 700                               struct cx231xx_dmaqueue *dma_q)
 701 {
 702         u32 height = 0;
 703
 704         height = ((dev->norm & V4L2_STD_625_50) ?
 705                   PAL_VBI_LINES : NTSC_VBI_LINES);
 706         if (dma_q->lines_completed == height && dma_q->current_field == 2)
 707                 return 1;
 708         else
 709                 return 0;
 710 }