drivers/media/usb/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 "cx231xx.h"
  23 #include <linux/init.h>
  24 #include <linux/list.h>
  25 #include <linux/module.h>
  26 #include <linux/kernel.h>
  27 #include <linux/bitmap.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/drv-intf/msp3400.h>
  36 #include <media/tuner.h>
  37
  38 #include "cx231xx-vbi.h"
  39
  40 static inline void print_err_status(struct cx231xx *dev, int packet, int status)
  41 {
  42         char *errmsg = "Unknown";
  43
  44         switch (status) {
  45         case -ENOENT:
  46                 errmsg = "unlinked synchronously";
  47                 break;
  48         case -ECONNRESET:
  49                 errmsg = "unlinked asynchronously";
  50                 break;
  51         case -ENOSR:
  52                 errmsg = "Buffer error (overrun)";
  53                 break;
  54         case -EPIPE:
  55                 errmsg = "Stalled (device not responding)";
  56                 break;
  57         case -EOVERFLOW:
  58                 errmsg = "Babble (bad cable?)";
  59                 break;
  60         case -EPROTO:
  61                 errmsg = "Bit-stuff error (bad cable?)";
  62                 break;
  63         case -EILSEQ:
  64                 errmsg = "CRC/Timeout (could be anything)";
  65                 break;
  66         case -ETIME:
  67                 errmsg = "Device does not respond";
  68                 break;
  69         }
  70         if (packet < 0) {
  71                 dev_err(dev->dev,
  72                         "URB status %d [%s].\n", status, errmsg);
  73         } else {
  74                 dev_err(dev->dev,
  75                         "URB packet %d, status %d [%s].\n",
  76                         packet, status, errmsg);
  77         }
  78 }
  79
  80 /*
  81  * Controls the isoc copy of each urb packet
  82  */
  83 static inline int cx231xx_isoc_vbi_copy(struct cx231xx *dev, struct urb *urb)
  84 {
  85         struct cx231xx_dmaqueue *dma_q = urb->context;
  86         int rc = 1;
  87         unsigned char *p_buffer;
  88         u32 bytes_parsed = 0, buffer_size = 0;
  89         u8 sav_eav = 0;
  90
  91         if (!dev)
  92                 return 0;
  93
  94         if (dev->state & DEV_DISCONNECTED)
  95                 return 0;
  96
  97         if (urb->status < 0) {
  98                 print_err_status(dev, -1, urb->status);
  99                 if (urb->status == -ENOENT)
 100                         return 0;
 101         }
 102
 103         /* get buffer pointer and length */
 104         p_buffer = urb->transfer_buffer;
 105         buffer_size = urb->actual_length;
 106
 107         if (buffer_size > 0) {
 108                 bytes_parsed = 0;
 109
 110                 if (dma_q->is_partial_line) {
 111                         /* Handle the case where we were working on a partial
 112                            line */
 113                         sav_eav = dma_q->last_sav;
 114                 } else {
 115                         /* Check for a SAV/EAV overlapping the
 116                            buffer boundary */
 117
 118                         sav_eav = cx231xx_find_boundary_SAV_EAV(p_buffer,
 119                                                           dma_q->partial_buf,
 120                                                           &bytes_parsed);
 121                 }
 122
 123                 sav_eav &= 0xF0;
 124                 /* Get the first line if we have some portion of an SAV/EAV from
 125                    the last buffer or a partial line */
 126                 if (sav_eav) {
 127                         bytes_parsed += cx231xx_get_vbi_line(dev, dma_q,
 128                                 sav_eav,                       /* SAV/EAV */
 129                                 p_buffer + bytes_parsed,       /* p_buffer */
 130                                 buffer_size - bytes_parsed);   /* buffer size */
 131                 }
 132
 133                 /* Now parse data that is completely in this buffer */
 134                 dma_q->is_partial_line = 0;
 135
 136                 while (bytes_parsed < buffer_size) {
 137                         u32 bytes_used = 0;
 138
 139                         sav_eav = cx231xx_find_next_SAV_EAV(
 140                                 p_buffer + bytes_parsed,        /* p_buffer */
 141                                 buffer_size - bytes_parsed, /* buffer size */
 142                                 &bytes_used);   /* bytes used to get SAV/EAV */
 143
 144                         bytes_parsed += bytes_used;
 145
 146                         sav_eav &= 0xF0;
 147                         if (sav_eav && (bytes_parsed < buffer_size)) {
 148                                 bytes_parsed += cx231xx_get_vbi_line(dev,
 149                                         dma_q, sav_eav, /* SAV/EAV */
 150                                         p_buffer+bytes_parsed, /* p_buffer */
 151                                         buffer_size-bytes_parsed);/*buf size*/
 152                         }
 153                 }
 154
 155                 /* Save the last four bytes of the buffer so we can
 156                 check the buffer boundary condition next time */
 157                 memcpy(dma_q->partial_buf, p_buffer + buffer_size - 4, 4);
 158                 bytes_parsed = 0;
 159         }
 160
 161         return rc;
 162 }
 163
 164 /* ------------------------------------------------------------------
 165         Vbi buf operations
 166    ------------------------------------------------------------------*/
 167
 168 static int
 169 vbi_buffer_setup(struct videobuf_queue *vq, unsigned int *count,
 170                  unsigned int *size)
 171 {
 172         struct cx231xx_fh *fh = vq->priv_data;
 173         struct cx231xx *dev = fh->dev;
 174         u32 height = 0;
 175
 176         height = ((dev->norm & V4L2_STD_625_50) ?
 177                   PAL_VBI_LINES : NTSC_VBI_LINES);
 178
 179         *size = (dev->width * height * 2 * 2);
 180         if (0 == *count)
 181                 *count = CX231XX_DEF_VBI_BUF;
 182
 183         if (*count < CX231XX_MIN_BUF)
 184                 *count = CX231XX_MIN_BUF;
 185
 186         return 0;
 187 }
 188
 189 /* This is called *without* dev->slock held; please keep it that way */
 190 static void free_buffer(struct videobuf_queue *vq, struct cx231xx_buffer *buf)
 191 {
 192         struct cx231xx_fh *fh = vq->priv_data;
 193         struct cx231xx *dev = fh->dev;
 194         unsigned long flags = 0;
 195         BUG_ON(in_interrupt());
 196
 197         /* We used to wait for the buffer to finish here, but this didn't work
 198            because, as we were keeping the state as VIDEOBUF_QUEUED,
 199            videobuf_queue_cancel marked it as finished for us.
 200            (Also, it could wedge forever if the hardware was misconfigured.)
 201
 202            This should be safe; by the time we get here, the buffer isn't
 203            queued anymore. If we ever start marking the buffers as
 204            VIDEOBUF_ACTIVE, it won't be, though.
 205          */
 206         spin_lock_irqsave(&dev->vbi_mode.slock, flags);
 207         if (dev->vbi_mode.bulk_ctl.buf == buf)
 208                 dev->vbi_mode.bulk_ctl.buf = NULL;
 209         spin_unlock_irqrestore(&dev->vbi_mode.slock, flags);
 210
 211         videobuf_vmalloc_free(&buf->vb);
 212         buf->vb.state = VIDEOBUF_NEEDS_INIT;
 213 }
 214
 215 static int
 216 vbi_buffer_prepare(struct videobuf_queue *vq, struct videobuf_buffer *vb,
 217                    enum v4l2_field field)
 218 {
 219         struct cx231xx_fh *fh = vq->priv_data;
 220         struct cx231xx_buffer *buf =
 221             container_of(vb, struct cx231xx_buffer, vb);
 222         struct cx231xx *dev = fh->dev;
 223         int rc = 0, urb_init = 0;
 224         u32 height = 0;
 225
 226         height = ((dev->norm & V4L2_STD_625_50) ?
 227                   PAL_VBI_LINES : NTSC_VBI_LINES);
 228         buf->vb.size = ((dev->width << 1) * height * 2);
 229
 230         if (0 != buf->vb.baddr && buf->vb.bsize < buf->vb.size)
 231                 return -EINVAL;
 232
 233         buf->vb.width = dev->width;
 234         buf->vb.height = height;
 235         buf->vb.field = field;
 236         buf->vb.field = V4L2_FIELD_SEQ_TB;
 237
 238         if (VIDEOBUF_NEEDS_INIT == buf->vb.state) {
 239                 rc = videobuf_iolock(vq, &buf->vb, NULL);
 240                 if (rc < 0)
 241                         goto fail;
 242         }
 243
 244         if (!dev->vbi_mode.bulk_ctl.num_bufs)
 245                 urb_init = 1;
 246
 247         if (urb_init) {
 248                 rc = cx231xx_init_vbi_isoc(dev, CX231XX_NUM_VBI_PACKETS,
 249                                            CX231XX_NUM_VBI_BUFS,
 250                                            dev->vbi_mode.alt_max_pkt_size[0],
 251                                            cx231xx_isoc_vbi_copy);
 252                 if (rc < 0)
 253                         goto fail;
 254         }
 255
 256         buf->vb.state = VIDEOBUF_PREPARED;
 257         return 0;
 258
 259 fail:
 260         free_buffer(vq, buf);
 261         return rc;
 262 }
 263
 264 static void
 265 vbi_buffer_queue(struct videobuf_queue *vq, struct videobuf_buffer *vb)
 266 {
 267         struct cx231xx_buffer *buf =
 268             container_of(vb, struct cx231xx_buffer, vb);
 269         struct cx231xx_fh *fh = vq->priv_data;
 270         struct cx231xx *dev = fh->dev;
 271         struct cx231xx_dmaqueue *vidq = &dev->vbi_mode.vidq;
 272
 273         buf->vb.state = VIDEOBUF_QUEUED;
 274         list_add_tail(&buf->vb.queue, &vidq->active);
 275
 276 }
 277
 278 static void vbi_buffer_release(struct videobuf_queue *vq,
 279                                struct videobuf_buffer *vb)
 280 {
 281         struct cx231xx_buffer *buf =
 282             container_of(vb, struct cx231xx_buffer, vb);
 283
 284
 285         free_buffer(vq, buf);
 286 }
 287
 288 const struct videobuf_queue_ops cx231xx_vbi_qops = {
 289         .buf_setup   = vbi_buffer_setup,
 290         .buf_prepare = vbi_buffer_prepare,
 291         .buf_queue   = vbi_buffer_queue,
 292         .buf_release = vbi_buffer_release,
 293 };
 294
 295 /* ------------------------------------------------------------------
 296         URB control
 297    ------------------------------------------------------------------*/
 298
 299 /*
 300  * IRQ callback, called by URB callback
 301  */
 302 static void cx231xx_irq_vbi_callback(struct urb *urb)
 303 {
 304         struct cx231xx_dmaqueue *dma_q = urb->context;
 305         struct cx231xx_video_mode *vmode =
 306             container_of(dma_q, struct cx231xx_video_mode, vidq);
 307         struct cx231xx *dev = container_of(vmode, struct cx231xx, vbi_mode);
 308         unsigned long flags;
 309
 310         switch (urb->status) {
 311         case 0:         /* success */
 312         case -ETIMEDOUT:        /* NAK */
 313                 break;
 314         case -ECONNRESET:       /* kill */
 315         case -ENOENT:
 316         case -ESHUTDOWN:
 317                 return;
 318         default:                /* error */
 319                 dev_err(dev->dev,
 320                         "urb completion error %d.\n", urb->status);
 321                 break;
 322         }
 323
 324         /* Copy data from URB */
 325         spin_lock_irqsave(&dev->vbi_mode.slock, flags);
 326         dev->vbi_mode.bulk_ctl.bulk_copy(dev, urb);
 327         spin_unlock_irqrestore(&dev->vbi_mode.slock, flags);
 328
 329         /* Reset status */
 330         urb->status = 0;
 331
 332         urb->status = usb_submit_urb(urb, GFP_ATOMIC);
 333         if (urb->status) {
 334                 dev_err(dev->dev, "urb resubmit failed (error=%i)\n",
 335                         urb->status);
 336         }
 337 }
 338
 339 /*
 340  * Stop and Deallocate URBs
 341  */
 342 void cx231xx_uninit_vbi_isoc(struct cx231xx *dev)
 343 {
 344         struct urb *urb;
 345         int i;
 346
 347         dev_dbg(dev->dev, "called cx231xx_uninit_vbi_isoc\n");
 348
 349         dev->vbi_mode.bulk_ctl.nfields = -1;
 350         for (i = 0; i < dev->vbi_mode.bulk_ctl.num_bufs; i++) {
 351                 urb = dev->vbi_mode.bulk_ctl.urb[i];
 352                 if (urb) {
 353                         if (!irqs_disabled())
 354                                 usb_kill_urb(urb);
 355                         else
 356                                 usb_unlink_urb(urb);
 357
 358                         if (dev->vbi_mode.bulk_ctl.transfer_buffer[i]) {
 359
 360                                 kfree(dev->vbi_mode.bulk_ctl.
 361                                       transfer_buffer[i]);
 362                                 dev->vbi_mode.bulk_ctl.transfer_buffer[i] =
 363                                     NULL;
 364                         }
 365                         usb_free_urb(urb);
 366                         dev->vbi_mode.bulk_ctl.urb[i] = NULL;
 367                 }
 368                 dev->vbi_mode.bulk_ctl.transfer_buffer[i] = NULL;
 369         }
 370
 371         kfree(dev->vbi_mode.bulk_ctl.urb);
 372         kfree(dev->vbi_mode.bulk_ctl.transfer_buffer);
 373
 374         dev->vbi_mode.bulk_ctl.urb = NULL;
 375         dev->vbi_mode.bulk_ctl.transfer_buffer = NULL;
 376         dev->vbi_mode.bulk_ctl.num_bufs = 0;
 377
 378         cx231xx_capture_start(dev, 0, Vbi);
 379 }
 380 EXPORT_SYMBOL_GPL(cx231xx_uninit_vbi_isoc);
 381
 382 /*
 383  * Allocate URBs and start IRQ
 384  */
 385 int cx231xx_init_vbi_isoc(struct cx231xx *dev, int max_packets,
 386                           int num_bufs, int max_pkt_size,
 387                           int (*bulk_copy) (struct cx231xx *dev,
 388                                             struct urb *urb))
 389 {
 390         struct cx231xx_dmaqueue *dma_q = &dev->vbi_mode.vidq;
 391         int i;
 392         int sb_size, pipe;
 393         struct urb *urb;
 394         int rc;
 395
 396         dev_dbg(dev->dev, "called cx231xx_vbi_isoc\n");
 397
 398         /* De-allocates all pending stuff */
 399         cx231xx_uninit_vbi_isoc(dev);
 400
 401         /* clear if any halt */
 402         usb_clear_halt(dev->udev,
 403                        usb_rcvbulkpipe(dev->udev,
 404                                        dev->vbi_mode.end_point_addr));
 405
 406         dev->vbi_mode.bulk_ctl.bulk_copy = bulk_copy;
 407         dev->vbi_mode.bulk_ctl.num_bufs = num_bufs;
 408         dma_q->pos = 0;
 409         dma_q->is_partial_line = 0;
 410         dma_q->last_sav = 0;
 411         dma_q->current_field = -1;
 412         dma_q->bytes_left_in_line = dev->width << 1;
 413         dma_q->lines_per_field = ((dev->norm & V4L2_STD_625_50) ?
 414                                   PAL_VBI_LINES : NTSC_VBI_LINES);
 415         dma_q->lines_completed = 0;
 416         for (i = 0; i < 8; i++)
 417                 dma_q->partial_buf[i] = 0;
 418
 419         dev->vbi_mode.bulk_ctl.urb = kcalloc(num_bufs, sizeof(void *),
 420                                              GFP_KERNEL);
 421         if (!dev->vbi_mode.bulk_ctl.urb) {
 422                 dev_err(dev->dev,
 423                         "cannot alloc memory for usb buffers\n");
 424                 return -ENOMEM;
 425         }
 426
 427         dev->vbi_mode.bulk_ctl.transfer_buffer =
 428             kcalloc(num_bufs, sizeof(void *), GFP_KERNEL);
 429         if (!dev->vbi_mode.bulk_ctl.transfer_buffer) {
 430                 dev_err(dev->dev,
 431                         "cannot allocate memory for usbtransfer\n");
 432                 kfree(dev->vbi_mode.bulk_ctl.urb);
 433                 return -ENOMEM;
 434         }
 435
 436         dev->vbi_mode.bulk_ctl.max_pkt_size = max_pkt_size;
 437         dev->vbi_mode.bulk_ctl.buf = NULL;
 438
 439         sb_size = max_packets * dev->vbi_mode.bulk_ctl.max_pkt_size;
 440
 441         /* allocate urbs and transfer buffers */
 442         for (i = 0; i < dev->vbi_mode.bulk_ctl.num_bufs; i++) {
 443
 444                 urb = usb_alloc_urb(0, GFP_KERNEL);
 445                 if (!urb) {
 446                         cx231xx_uninit_vbi_isoc(dev);
 447                         return -ENOMEM;
 448                 }
 449                 dev->vbi_mode.bulk_ctl.urb[i] = urb;
 450                 urb->transfer_flags = 0;
 451
 452                 dev->vbi_mode.bulk_ctl.transfer_buffer[i] =
 453                     kzalloc(sb_size, GFP_KERNEL);
 454                 if (!dev->vbi_mode.bulk_ctl.transfer_buffer[i]) {
 455                         dev_err(dev->dev,
 456                                 "unable to allocate %i bytes for transfer buffer %i%s\n",
 457                                 sb_size, i,
 458                                 in_interrupt() ? " while in int" : "");
 459                         cx231xx_uninit_vbi_isoc(dev);
 460                         return -ENOMEM;
 461                 }
 462
 463                 pipe = usb_rcvbulkpipe(dev->udev, dev->vbi_mode.end_point_addr);
 464                 usb_fill_bulk_urb(urb, dev->udev, pipe,
 465                                   dev->vbi_mode.bulk_ctl.transfer_buffer[i],
 466                                   sb_size, cx231xx_irq_vbi_callback, dma_q);
 467         }
 468
 469         init_waitqueue_head(&dma_q->wq);
 470
 471         /* submit urbs and enables IRQ */
 472         for (i = 0; i < dev->vbi_mode.bulk_ctl.num_bufs; i++) {
 473                 rc = usb_submit_urb(dev->vbi_mode.bulk_ctl.urb[i], GFP_ATOMIC);
 474                 if (rc) {
 475                         dev_err(dev->dev,
 476                                 "submit of urb %i failed (error=%i)\n", i, rc);
 477                         cx231xx_uninit_vbi_isoc(dev);
 478                         return rc;
 479                 }
 480         }
 481
 482         cx231xx_capture_start(dev, 1, Vbi);
 483
 484         return 0;
 485 }
 486 EXPORT_SYMBOL_GPL(cx231xx_init_vbi_isoc);
 487
 488 u32 cx231xx_get_vbi_line(struct cx231xx *dev, struct cx231xx_dmaqueue *dma_q,
 489                          u8 sav_eav, u8 *p_buffer, u32 buffer_size)
 490 {
 491         u32 bytes_copied = 0;
 492         int current_field = -1;
 493
 494         switch (sav_eav) {
 495
 496         case SAV_VBI_FIELD1:
 497                 current_field = 1;
 498                 break;
 499
 500         case SAV_VBI_FIELD2:
 501                 current_field = 2;
 502                 break;
 503         default:
 504                 break;
 505         }
 506
 507         if (current_field < 0)
 508                 return bytes_copied;
 509
 510         dma_q->last_sav = sav_eav;
 511
 512         bytes_copied =
 513             cx231xx_copy_vbi_line(dev, dma_q, p_buffer, buffer_size,
 514                                   current_field);
 515
 516         return bytes_copied;
 517 }
 518
 519 /*
 520  * Announces that a buffer were filled and request the next
 521  */
 522 static inline void vbi_buffer_filled(struct cx231xx *dev,
 523                                      struct cx231xx_dmaqueue *dma_q,
 524                                      struct cx231xx_buffer *buf)
 525 {
 526         /* Advice that buffer was filled */
 527         /* dev_dbg(dev->dev, "[%p/%d] wakeup\n", buf, buf->vb.i); */
 528
 529         buf->vb.state = VIDEOBUF_DONE;
 530         buf->vb.field_count++;
 531         v4l2_get_timestamp(&buf->vb.ts);
 532
 533         dev->vbi_mode.bulk_ctl.buf = NULL;
 534
 535         list_del(&buf->vb.queue);
 536         wake_up(&buf->vb.done);
 537 }
 538
 539 u32 cx231xx_copy_vbi_line(struct cx231xx *dev, struct cx231xx_dmaqueue *dma_q,
 540                           u8 *p_line, u32 length, int field_number)
 541 {
 542         u32 bytes_to_copy;
 543         struct cx231xx_buffer *buf;
 544         u32 _line_size = dev->width * 2;
 545
 546         if (dma_q->current_field == -1) {
 547                 /* Just starting up */
 548                 cx231xx_reset_vbi_buffer(dev, dma_q);
 549         }
 550
 551         if (dma_q->current_field != field_number)
 552                 dma_q->lines_completed = 0;
 553
 554         /* get the buffer pointer */
 555         buf = dev->vbi_mode.bulk_ctl.buf;
 556
 557         /* Remember the field number for next time */
 558         dma_q->current_field = field_number;
 559
 560         bytes_to_copy = dma_q->bytes_left_in_line;
 561         if (bytes_to_copy > length)
 562                 bytes_to_copy = length;
 563
 564         if (dma_q->lines_completed >= dma_q->lines_per_field) {
 565                 dma_q->bytes_left_in_line -= bytes_to_copy;
 566                 dma_q->is_partial_line =
 567                     (dma_q->bytes_left_in_line == 0) ? 0 : 1;
 568                 return 0;
 569         }
 570
 571         dma_q->is_partial_line = 1;
 572
 573         /* If we don't have a buffer, just return the number of bytes we would
 574            have copied if we had a buffer. */
 575         if (!buf) {
 576                 dma_q->bytes_left_in_line -= bytes_to_copy;
 577                 dma_q->is_partial_line =
 578                     (dma_q->bytes_left_in_line == 0) ? 0 : 1;
 579                 return bytes_to_copy;
 580         }
 581
 582         /* copy the data to video buffer */
 583         cx231xx_do_vbi_copy(dev, dma_q, p_line, bytes_to_copy);
 584
 585         dma_q->pos += bytes_to_copy;
 586         dma_q->bytes_left_in_line -= bytes_to_copy;
 587
 588         if (dma_q->bytes_left_in_line == 0) {
 589
 590                 dma_q->bytes_left_in_line = _line_size;
 591                 dma_q->lines_completed++;
 592                 dma_q->is_partial_line = 0;
 593
 594                 if (cx231xx_is_vbi_buffer_done(dev, dma_q) && buf) {
 595
 596                         vbi_buffer_filled(dev, dma_q, buf);
 597
 598                         dma_q->pos = 0;
 599                         dma_q->lines_completed = 0;
 600                         cx231xx_reset_vbi_buffer(dev, dma_q);
 601                 }
 602         }
 603
 604         return bytes_to_copy;
 605 }
 606
 607 /*
 608  * video-buf generic routine to get the next available buffer
 609  */
 610 static inline void get_next_vbi_buf(struct cx231xx_dmaqueue *dma_q,
 611                                     struct cx231xx_buffer **buf)
 612 {
 613         struct cx231xx_video_mode *vmode =
 614             container_of(dma_q, struct cx231xx_video_mode, vidq);
 615         struct cx231xx *dev = container_of(vmode, struct cx231xx, vbi_mode);
 616         char *outp;
 617
 618         if (list_empty(&dma_q->active)) {
 619                 dev_err(dev->dev, "No active queue to serve\n");
 620                 dev->vbi_mode.bulk_ctl.buf = NULL;
 621                 *buf = NULL;
 622                 return;
 623         }
 624
 625         /* Get the next buffer */
 626         *buf = list_entry(dma_q->active.next, struct cx231xx_buffer, vb.queue);
 627
 628         /* Cleans up buffer - Useful for testing for frame/URB loss */
 629         outp = videobuf_to_vmalloc(&(*buf)->vb);
 630         memset(outp, 0, (*buf)->vb.size);
 631
 632         dev->vbi_mode.bulk_ctl.buf = *buf;
 633
 634         return;
 635 }
 636
 637 void cx231xx_reset_vbi_buffer(struct cx231xx *dev,
 638                               struct cx231xx_dmaqueue *dma_q)
 639 {
 640         struct cx231xx_buffer *buf;
 641
 642         buf = dev->vbi_mode.bulk_ctl.buf;
 643
 644         if (buf == NULL) {
 645                 /* first try to get the buffer */
 646                 get_next_vbi_buf(dma_q, &buf);
 647
 648                 dma_q->pos = 0;
 649                 dma_q->current_field = -1;
 650         }
 651
 652         dma_q->bytes_left_in_line = dev->width << 1;
 653         dma_q->lines_completed = 0;
 654 }
 655
 656 int cx231xx_do_vbi_copy(struct cx231xx *dev, struct cx231xx_dmaqueue *dma_q,
 657                         u8 *p_buffer, u32 bytes_to_copy)
 658 {
 659         u8 *p_out_buffer = NULL;
 660         u32 current_line_bytes_copied = 0;
 661         struct cx231xx_buffer *buf;
 662         u32 _line_size = dev->width << 1;
 663         void *startwrite;
 664         int offset, lencopy;
 665
 666         buf = dev->vbi_mode.bulk_ctl.buf;
 667
 668         if (buf == NULL)
 669                 return -EINVAL;
 670
 671         p_out_buffer = videobuf_to_vmalloc(&buf->vb);
 672
 673         if (dma_q->bytes_left_in_line != _line_size) {
 674                 current_line_bytes_copied =
 675                     _line_size - dma_q->bytes_left_in_line;
 676         }
 677
 678         offset = (dma_q->lines_completed * _line_size) +
 679                  current_line_bytes_copied;
 680
 681         if (dma_q->current_field == 2) {
 682                 /* Populate the second half of the frame */
 683                 offset += (dev->width * 2 * dma_q->lines_per_field);
 684         }
 685
 686         /* prepare destination address */
 687         startwrite = p_out_buffer + offset;
 688
 689         lencopy = dma_q->bytes_left_in_line > bytes_to_copy ?
 690                   bytes_to_copy : dma_q->bytes_left_in_line;
 691
 692         memcpy(startwrite, p_buffer, lencopy);
 693
 694         return 0;
 695 }
 696
 697 u8 cx231xx_is_vbi_buffer_done(struct cx231xx *dev,
 698                               struct cx231xx_dmaqueue *dma_q)
 699 {
 700         u32 height = 0;
 701
 702         height = ((dev->norm & V4L2_STD_625_50) ?
 703                   PAL_VBI_LINES : NTSC_VBI_LINES);
 704         if (dma_q->lines_completed == height && dma_q->current_field == 2)
 705                 return 1;
 706         else
 707                 return 0;
 708 }