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 synchronuously";
  47                 break;
  48         case -ECONNRESET:
  49                 errmsg = "unlinked asynchronuously";
  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 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
 309         switch (urb->status) {
 310         case 0:         /* success */
 311         case -ETIMEDOUT:        /* NAK */
 312                 break;
 313         case -ECONNRESET:       /* kill */
 314         case -ENOENT:
 315         case -ESHUTDOWN:
 316                 return;
 317         default:                /* error */
 318                 dev_err(dev->dev,
 319                         "urb completition error %d.\n", urb->status);
 320                 break;
 321         }
 322
 323         /* Copy data from URB */
 324         spin_lock(&dev->vbi_mode.slock);
 325         dev->vbi_mode.bulk_ctl.bulk_copy(dev, urb);
 326         spin_unlock(&dev->vbi_mode.slock);
 327
 328         /* Reset status */
 329         urb->status = 0;
 330
 331         urb->status = usb_submit_urb(urb, GFP_ATOMIC);
 332         if (urb->status) {
 333                 dev_err(dev->dev, "urb resubmit failed (error=%i)\n",
 334                         urb->status);
 335         }
 336 }
 337
 338 /*
 339  * Stop and Deallocate URBs
 340  */
 341 void cx231xx_uninit_vbi_isoc(struct cx231xx *dev)
 342 {
 343         struct urb *urb;
 344         int i;
 345
 346         dev_dbg(dev->dev, "called cx231xx_uninit_vbi_isoc\n");
 347
 348         dev->vbi_mode.bulk_ctl.nfields = -1;
 349         for (i = 0; i < dev->vbi_mode.bulk_ctl.num_bufs; i++) {
 350                 urb = dev->vbi_mode.bulk_ctl.urb[i];
 351                 if (urb) {
 352                         if (!irqs_disabled())
 353                                 usb_kill_urb(urb);
 354                         else
 355                                 usb_unlink_urb(urb);
 356
 357                         if (dev->vbi_mode.bulk_ctl.transfer_buffer[i]) {
 358
 359                                 kfree(dev->vbi_mode.bulk_ctl.
 360                                       transfer_buffer[i]);
 361                                 dev->vbi_mode.bulk_ctl.transfer_buffer[i] =
 362                                     NULL;
 363                         }
 364                         usb_free_urb(urb);
 365                         dev->vbi_mode.bulk_ctl.urb[i] = NULL;
 366                 }
 367                 dev->vbi_mode.bulk_ctl.transfer_buffer[i] = NULL;
 368         }
 369
 370         kfree(dev->vbi_mode.bulk_ctl.urb);
 371         kfree(dev->vbi_mode.bulk_ctl.transfer_buffer);
 372
 373         dev->vbi_mode.bulk_ctl.urb = NULL;
 374         dev->vbi_mode.bulk_ctl.transfer_buffer = NULL;
 375         dev->vbi_mode.bulk_ctl.num_bufs = 0;
 376
 377         cx231xx_capture_start(dev, 0, Vbi);
 378 }
 379 EXPORT_SYMBOL_GPL(cx231xx_uninit_vbi_isoc);
 380
 381 /*
 382  * Allocate URBs and start IRQ
 383  */
 384 int cx231xx_init_vbi_isoc(struct cx231xx *dev, int max_packets,
 385                           int num_bufs, int max_pkt_size,
 386                           int (*bulk_copy) (struct cx231xx *dev,
 387                                             struct urb *urb))
 388 {
 389         struct cx231xx_dmaqueue *dma_q = &dev->vbi_mode.vidq;
 390         int i;
 391         int sb_size, pipe;
 392         struct urb *urb;
 393         int rc;
 394
 395         dev_dbg(dev->dev, "called cx231xx_vbi_isoc\n");
 396
 397         /* De-allocates all pending stuff */
 398         cx231xx_uninit_vbi_isoc(dev);
 399
 400         /* clear if any halt */
 401         usb_clear_halt(dev->udev,
 402                        usb_rcvbulkpipe(dev->udev,
 403                                        dev->vbi_mode.end_point_addr));
 404
 405         dev->vbi_mode.bulk_ctl.bulk_copy = bulk_copy;
 406         dev->vbi_mode.bulk_ctl.num_bufs = num_bufs;
 407         dma_q->pos = 0;
 408         dma_q->is_partial_line = 0;
 409         dma_q->last_sav = 0;
 410         dma_q->current_field = -1;
 411         dma_q->bytes_left_in_line = dev->width << 1;
 412         dma_q->lines_per_field = ((dev->norm & V4L2_STD_625_50) ?
 413                                   PAL_VBI_LINES : NTSC_VBI_LINES);
 414         dma_q->lines_completed = 0;
 415         for (i = 0; i < 8; i++)
 416                 dma_q->partial_buf[i] = 0;
 417
 418         dev->vbi_mode.bulk_ctl.urb = kzalloc(sizeof(void *) * num_bufs,
 419                                              GFP_KERNEL);
 420         if (!dev->vbi_mode.bulk_ctl.urb) {
 421                 dev_err(dev->dev,
 422                         "cannot alloc memory for usb buffers\n");
 423                 return -ENOMEM;
 424         }
 425
 426         dev->vbi_mode.bulk_ctl.transfer_buffer =
 427             kzalloc(sizeof(void *) * num_bufs, GFP_KERNEL);
 428         if (!dev->vbi_mode.bulk_ctl.transfer_buffer) {
 429                 dev_err(dev->dev,
 430                         "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_uninit_vbi_isoc(dev);
 446                         return -ENOMEM;
 447                 }
 448                 dev->vbi_mode.bulk_ctl.urb[i] = urb;
 449                 urb->transfer_flags = 0;
 450
 451                 dev->vbi_mode.bulk_ctl.transfer_buffer[i] =
 452                     kzalloc(sb_size, GFP_KERNEL);
 453                 if (!dev->vbi_mode.bulk_ctl.transfer_buffer[i]) {
 454                         dev_err(dev->dev,
 455                                 "unable to allocate %i bytes for transfer buffer %i%s\n",
 456                                 sb_size, i,
 457                                 in_interrupt() ? " while in int" : "");
 458                         cx231xx_uninit_vbi_isoc(dev);
 459                         return -ENOMEM;
 460                 }
 461
 462                 pipe = usb_rcvbulkpipe(dev->udev, dev->vbi_mode.end_point_addr);
 463                 usb_fill_bulk_urb(urb, dev->udev, pipe,
 464                                   dev->vbi_mode.bulk_ctl.transfer_buffer[i],
 465                                   sb_size, cx231xx_irq_vbi_callback, dma_q);
 466         }
 467
 468         init_waitqueue_head(&dma_q->wq);
 469
 470         /* submit urbs and enables IRQ */
 471         for (i = 0; i < dev->vbi_mode.bulk_ctl.num_bufs; i++) {
 472                 rc = usb_submit_urb(dev->vbi_mode.bulk_ctl.urb[i], GFP_ATOMIC);
 473                 if (rc) {
 474                         dev_err(dev->dev,
 475                                 "submit of urb %i failed (error=%i)\n", i, rc);
 476                         cx231xx_uninit_vbi_isoc(dev);
 477                         return rc;
 478                 }
 479         }
 480
 481         cx231xx_capture_start(dev, 1, Vbi);
 482
 483         return 0;
 484 }
 485 EXPORT_SYMBOL_GPL(cx231xx_init_vbi_isoc);
 486
 487 u32 cx231xx_get_vbi_line(struct cx231xx *dev, struct cx231xx_dmaqueue *dma_q,
 488                          u8 sav_eav, u8 *p_buffer, u32 buffer_size)
 489 {
 490         u32 bytes_copied = 0;
 491         int current_field = -1;
 492
 493         switch (sav_eav) {
 494
 495         case SAV_VBI_FIELD1:
 496                 current_field = 1;
 497                 break;
 498
 499         case SAV_VBI_FIELD2:
 500                 current_field = 2;
 501                 break;
 502         default:
 503                 break;
 504         }
 505
 506         if (current_field < 0)
 507                 return bytes_copied;
 508
 509         dma_q->last_sav = sav_eav;
 510
 511         bytes_copied =
 512             cx231xx_copy_vbi_line(dev, dma_q, p_buffer, buffer_size,
 513                                   current_field);
 514
 515         return bytes_copied;
 516 }
 517
 518 /*
 519  * Announces that a buffer were filled and request the next
 520  */
 521 static inline void vbi_buffer_filled(struct cx231xx *dev,
 522                                      struct cx231xx_dmaqueue *dma_q,
 523                                      struct cx231xx_buffer *buf)
 524 {
 525         /* Advice that buffer was filled */
 526         /* dev_dbg(dev->dev, "[%p/%d] wakeup\n", buf, buf->vb.i); */
 527
 528         buf->vb.state = VIDEOBUF_DONE;
 529         buf->vb.field_count++;
 530         v4l2_get_timestamp(&buf->vb.ts);
 531
 532         dev->vbi_mode.bulk_ctl.buf = NULL;
 533
 534         list_del(&buf->vb.queue);
 535         wake_up(&buf->vb.done);
 536 }
 537
 538 u32 cx231xx_copy_vbi_line(struct cx231xx *dev, struct cx231xx_dmaqueue *dma_q,
 539                           u8 *p_line, u32 length, int field_number)
 540 {
 541         u32 bytes_to_copy;
 542         struct cx231xx_buffer *buf;
 543         u32 _line_size = dev->width * 2;
 544
 545         if (dma_q->current_field == -1) {
 546                 /* Just starting up */
 547                 cx231xx_reset_vbi_buffer(dev, dma_q);
 548         }
 549
 550         if (dma_q->current_field != field_number)
 551                 dma_q->lines_completed = 0;
 552
 553         /* get the buffer pointer */
 554         buf = dev->vbi_mode.bulk_ctl.buf;
 555
 556         /* Remember the field number for next time */
 557         dma_q->current_field = field_number;
 558
 559         bytes_to_copy = dma_q->bytes_left_in_line;
 560         if (bytes_to_copy > length)
 561                 bytes_to_copy = length;
 562
 563         if (dma_q->lines_completed >= dma_q->lines_per_field) {
 564                 dma_q->bytes_left_in_line -= bytes_to_copy;
 565                 dma_q->is_partial_line =
 566                     (dma_q->bytes_left_in_line == 0) ? 0 : 1;
 567                 return 0;
 568         }
 569
 570         dma_q->is_partial_line = 1;
 571
 572         /* If we don't have a buffer, just return the number of bytes we would
 573            have copied if we had a buffer. */
 574         if (!buf) {
 575                 dma_q->bytes_left_in_line -= bytes_to_copy;
 576                 dma_q->is_partial_line =
 577                     (dma_q->bytes_left_in_line == 0) ? 0 : 1;
 578                 return bytes_to_copy;
 579         }
 580
 581         /* copy the data to video buffer */
 582         cx231xx_do_vbi_copy(dev, dma_q, p_line, bytes_to_copy);
 583
 584         dma_q->pos += bytes_to_copy;
 585         dma_q->bytes_left_in_line -= bytes_to_copy;
 586
 587         if (dma_q->bytes_left_in_line == 0) {
 588
 589                 dma_q->bytes_left_in_line = _line_size;
 590                 dma_q->lines_completed++;
 591                 dma_q->is_partial_line = 0;
 592
 593                 if (cx231xx_is_vbi_buffer_done(dev, dma_q) && buf) {
 594
 595                         vbi_buffer_filled(dev, dma_q, buf);
 596
 597                         dma_q->pos = 0;
 598                         dma_q->lines_completed = 0;
 599                         cx231xx_reset_vbi_buffer(dev, dma_q);
 600                 }
 601         }
 602
 603         return bytes_to_copy;
 604 }
 605
 606 /*
 607  * video-buf generic routine to get the next available buffer
 608  */
 609 static inline void get_next_vbi_buf(struct cx231xx_dmaqueue *dma_q,
 610                                     struct cx231xx_buffer **buf)
 611 {
 612         struct cx231xx_video_mode *vmode =
 613             container_of(dma_q, struct cx231xx_video_mode, vidq);
 614         struct cx231xx *dev = container_of(vmode, struct cx231xx, vbi_mode);
 615         char *outp;
 616
 617         if (list_empty(&dma_q->active)) {
 618                 dev_err(dev->dev, "No active queue to serve\n");
 619                 dev->vbi_mode.bulk_ctl.buf = NULL;
 620                 *buf = NULL;
 621                 return;
 622         }
 623
 624         /* Get the next buffer */
 625         *buf = list_entry(dma_q->active.next, struct cx231xx_buffer, vb.queue);
 626
 627         /* Cleans up buffer - Useful for testing for frame/URB loss */
 628         outp = videobuf_to_vmalloc(&(*buf)->vb);
 629         memset(outp, 0, (*buf)->vb.size);
 630
 631         dev->vbi_mode.bulk_ctl.buf = *buf;
 632
 633         return;
 634 }
 635
 636 void cx231xx_reset_vbi_buffer(struct cx231xx *dev,
 637                               struct cx231xx_dmaqueue *dma_q)
 638 {
 639         struct cx231xx_buffer *buf;
 640
 641         buf = dev->vbi_mode.bulk_ctl.buf;
 642
 643         if (buf == NULL) {
 644                 /* first try to get the buffer */
 645                 get_next_vbi_buf(dma_q, &buf);
 646
 647                 dma_q->pos = 0;
 648                 dma_q->current_field = -1;
 649         }
 650
 651         dma_q->bytes_left_in_line = dev->width << 1;
 652         dma_q->lines_completed = 0;
 653 }
 654
 655 int cx231xx_do_vbi_copy(struct cx231xx *dev, struct cx231xx_dmaqueue *dma_q,
 656                         u8 *p_buffer, u32 bytes_to_copy)
 657 {
 658         u8 *p_out_buffer = NULL;
 659         u32 current_line_bytes_copied = 0;
 660         struct cx231xx_buffer *buf;
 661         u32 _line_size = dev->width << 1;
 662         void *startwrite;
 663         int offset, lencopy;
 664
 665         buf = dev->vbi_mode.bulk_ctl.buf;
 666
 667         if (buf == NULL)
 668                 return -EINVAL;
 669
 670         p_out_buffer = videobuf_to_vmalloc(&buf->vb);
 671
 672         if (dma_q->bytes_left_in_line != _line_size) {
 673                 current_line_bytes_copied =
 674                     _line_size - dma_q->bytes_left_in_line;
 675         }
 676
 677         offset = (dma_q->lines_completed * _line_size) +
 678                  current_line_bytes_copied;
 679
 680         if (dma_q->current_field == 2) {
 681                 /* Populate the second half of the frame */
 682                 offset += (dev->width * 2 * dma_q->lines_per_field);
 683         }
 684
 685         /* prepare destination address */
 686         startwrite = p_out_buffer + offset;
 687
 688         lencopy = dma_q->bytes_left_in_line > bytes_to_copy ?
 689                   bytes_to_copy : dma_q->bytes_left_in_line;
 690
 691         memcpy(startwrite, p_buffer, lencopy);
 692
 693         return 0;
 694 }
 695
 696 u8 cx231xx_is_vbi_buffer_done(struct cx231xx *dev,
 697                               struct cx231xx_dmaqueue *dma_q)
 698 {
 699         u32 height = 0;
 700
 701         height = ((dev->norm & V4L2_STD_625_50) ?
 702                   PAL_VBI_LINES : NTSC_VBI_LINES);
 703         if (dma_q->lines_completed == height && dma_q->current_field == 2)
 704                 return 1;
 705         else
 706                 return 0;
 707 }