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_buffer *buf;
  87         struct cx231xx_dmaqueue *dma_q = urb->context;
  88         int rc = 1;
  89         unsigned char *p_buffer;
  90         u32 bytes_parsed = 0, buffer_size = 0;
  91         u8 sav_eav = 0;
  92
  93         if (!dev)
  94                 return 0;
  95
  96         if ((dev->state & DEV_DISCONNECTED) || (dev->state & DEV_MISCONFIGURED))
  97                 return 0;
  98
  99         if (urb->status < 0) {
 100                 print_err_status(dev, -1, urb->status);
 101                 if (urb->status == -ENOENT)
 102                         return 0;
 103         }
 104
 105         buf = dev->vbi_mode.bulk_ctl.buf;
 106
 107         /* get buffer pointer and length */
 108         p_buffer = urb->transfer_buffer;
 109         buffer_size = urb->actual_length;
 110
 111         if (buffer_size > 0) {
 112                 bytes_parsed = 0;
 113
 114                 if (dma_q->is_partial_line) {
 115                         /* Handle the case where we were working on a partial
 116                            line */
 117                         sav_eav = dma_q->last_sav;
 118                 } else {
 119                         /* Check for a SAV/EAV overlapping the
 120                            buffer boundary */
 121
 122                         sav_eav = cx231xx_find_boundary_SAV_EAV(p_buffer,
 123                                                           dma_q->partial_buf,
 124                                                           &bytes_parsed);
 125                 }
 126
 127                 sav_eav &= 0xF0;
 128                 /* Get the first line if we have some portion of an SAV/EAV from
 129                    the last buffer or a partial line */
 130                 if (sav_eav) {
 131                         bytes_parsed += cx231xx_get_vbi_line(dev, dma_q,
 132                                 sav_eav,                       /* SAV/EAV */
 133                                 p_buffer + bytes_parsed,       /* p_buffer */
 134                                 buffer_size - bytes_parsed);   /* buffer size */
 135                 }
 136
 137                 /* Now parse data that is completely in this buffer */
 138                 dma_q->is_partial_line = 0;
 139
 140                 while (bytes_parsed < buffer_size) {
 141                         u32 bytes_used = 0;
 142
 143                         sav_eav = cx231xx_find_next_SAV_EAV(
 144                                 p_buffer + bytes_parsed,        /* p_buffer */
 145                                 buffer_size - bytes_parsed, /* buffer size */
 146                                 &bytes_used);   /* bytes used to get SAV/EAV */
 147
 148                         bytes_parsed += bytes_used;
 149
 150                         sav_eav &= 0xF0;
 151                         if (sav_eav && (bytes_parsed < buffer_size)) {
 152                                 bytes_parsed += cx231xx_get_vbi_line(dev,
 153                                         dma_q, sav_eav, /* SAV/EAV */
 154                                         p_buffer+bytes_parsed, /* p_buffer */
 155                                         buffer_size-bytes_parsed);/*buf size*/
 156                         }
 157                 }
 158
 159                 /* Save the last four bytes of the buffer so we can
 160                 check the buffer boundary condition next time */
 161                 memcpy(dma_q->partial_buf, p_buffer + buffer_size - 4, 4);
 162                 bytes_parsed = 0;
 163         }
 164
 165         return rc;
 166 }
 167
 168 /* ------------------------------------------------------------------
 169         Vbi buf operations
 170    ------------------------------------------------------------------*/
 171
 172 static int
 173 vbi_buffer_setup(struct videobuf_queue *vq, unsigned int *count,
 174                  unsigned int *size)
 175 {
 176         struct cx231xx_fh *fh = vq->priv_data;
 177         struct cx231xx *dev = fh->dev;
 178         u32 height = 0;
 179
 180         height = ((dev->norm & V4L2_STD_625_50) ?
 181                   PAL_VBI_LINES : NTSC_VBI_LINES);
 182
 183         *size = (dev->width * height * 2 * 2);
 184         if (0 == *count)
 185                 *count = CX231XX_DEF_VBI_BUF;
 186
 187         if (*count < CX231XX_MIN_BUF)
 188                 *count = CX231XX_MIN_BUF;
 189
 190         return 0;
 191 }
 192
 193 /* This is called *without* dev->slock held; please keep it that way */
 194 static void free_buffer(struct videobuf_queue *vq, struct cx231xx_buffer *buf)
 195 {
 196         struct cx231xx_fh *fh = vq->priv_data;
 197         struct cx231xx *dev = fh->dev;
 198         unsigned long flags = 0;
 199         if (in_interrupt())
 200                 BUG();
 201
 202         /* We used to wait for the buffer to finish here, but this didn't work
 203            because, as we were keeping the state as VIDEOBUF_QUEUED,
 204            videobuf_queue_cancel marked it as finished for us.
 205            (Also, it could wedge forever if the hardware was misconfigured.)
 206
 207            This should be safe; by the time we get here, the buffer isn't
 208            queued anymore. If we ever start marking the buffers as
 209            VIDEOBUF_ACTIVE, it won't be, though.
 210          */
 211         spin_lock_irqsave(&dev->vbi_mode.slock, flags);
 212         if (dev->vbi_mode.bulk_ctl.buf == buf)
 213                 dev->vbi_mode.bulk_ctl.buf = NULL;
 214         spin_unlock_irqrestore(&dev->vbi_mode.slock, flags);
 215
 216         videobuf_vmalloc_free(&buf->vb);
 217         buf->vb.state = VIDEOBUF_NEEDS_INIT;
 218 }
 219
 220 static int
 221 vbi_buffer_prepare(struct videobuf_queue *vq, struct videobuf_buffer *vb,
 222                    enum v4l2_field field)
 223 {
 224         struct cx231xx_fh *fh = vq->priv_data;
 225         struct cx231xx_buffer *buf =
 226             container_of(vb, struct cx231xx_buffer, vb);
 227         struct cx231xx *dev = fh->dev;
 228         int rc = 0, urb_init = 0;
 229         u32 height = 0;
 230
 231         height = ((dev->norm & V4L2_STD_625_50) ?
 232                   PAL_VBI_LINES : NTSC_VBI_LINES);
 233         buf->vb.size = ((dev->width << 1) * height * 2);
 234
 235         if (0 != buf->vb.baddr && buf->vb.bsize < buf->vb.size)
 236                 return -EINVAL;
 237
 238         buf->vb.width = dev->width;
 239         buf->vb.height = height;
 240         buf->vb.field = field;
 241         buf->vb.field = V4L2_FIELD_SEQ_TB;
 242
 243         if (VIDEOBUF_NEEDS_INIT == buf->vb.state) {
 244                 rc = videobuf_iolock(vq, &buf->vb, NULL);
 245                 if (rc < 0)
 246                         goto fail;
 247         }
 248
 249         if (!dev->vbi_mode.bulk_ctl.num_bufs)
 250                 urb_init = 1;
 251
 252         if (urb_init) {
 253                 rc = cx231xx_init_vbi_isoc(dev, CX231XX_NUM_VBI_PACKETS,
 254                                            CX231XX_NUM_VBI_BUFS,
 255                                            dev->vbi_mode.alt_max_pkt_size[0],
 256                                            cx231xx_isoc_vbi_copy);
 257                 if (rc < 0)
 258                         goto fail;
 259         }
 260
 261         buf->vb.state = VIDEOBUF_PREPARED;
 262         return 0;
 263
 264 fail:
 265         free_buffer(vq, buf);
 266         return rc;
 267 }
 268
 269 static void
 270 vbi_buffer_queue(struct videobuf_queue *vq, struct videobuf_buffer *vb)
 271 {
 272         struct cx231xx_buffer *buf =
 273             container_of(vb, struct cx231xx_buffer, vb);
 274         struct cx231xx_fh *fh = vq->priv_data;
 275         struct cx231xx *dev = fh->dev;
 276         struct cx231xx_dmaqueue *vidq = &dev->vbi_mode.vidq;
 277
 278         buf->vb.state = VIDEOBUF_QUEUED;
 279         list_add_tail(&buf->vb.queue, &vidq->active);
 280
 281 }
 282
 283 static void vbi_buffer_release(struct videobuf_queue *vq,
 284                                struct videobuf_buffer *vb)
 285 {
 286         struct cx231xx_buffer *buf =
 287             container_of(vb, struct cx231xx_buffer, vb);
 288
 289
 290         free_buffer(vq, buf);
 291 }
 292
 293 struct videobuf_queue_ops cx231xx_vbi_qops = {
 294         .buf_setup   = vbi_buffer_setup,
 295         .buf_prepare = vbi_buffer_prepare,
 296         .buf_queue   = vbi_buffer_queue,
 297         .buf_release = vbi_buffer_release,
 298 };
 299
 300 /* ------------------------------------------------------------------
 301         URB control
 302    ------------------------------------------------------------------*/
 303
 304 /*
 305  * IRQ callback, called by URB callback
 306  */
 307 static void cx231xx_irq_vbi_callback(struct urb *urb)
 308 {
 309         struct cx231xx_dmaqueue *dma_q = urb->context;
 310         struct cx231xx_video_mode *vmode =
 311             container_of(dma_q, struct cx231xx_video_mode, vidq);
 312         struct cx231xx *dev = container_of(vmode, struct cx231xx, vbi_mode);
 313         int rc;
 314
 315         switch (urb->status) {
 316         case 0:         /* success */
 317         case -ETIMEDOUT:        /* NAK */
 318                 break;
 319         case -ECONNRESET:       /* kill */
 320         case -ENOENT:
 321         case -ESHUTDOWN:
 322                 return;
 323         default:                /* error */
 324                 cx231xx_err(DRIVER_NAME "urb completition error %d.\n",
 325                             urb->status);
 326                 break;
 327         }
 328
 329         /* Copy data from URB */
 330         spin_lock(&dev->vbi_mode.slock);
 331         rc = dev->vbi_mode.bulk_ctl.bulk_copy(dev, urb);
 332         spin_unlock(&dev->vbi_mode.slock);
 333
 334         /* Reset status */
 335         urb->status = 0;
 336
 337         urb->status = usb_submit_urb(urb, GFP_ATOMIC);
 338         if (urb->status) {
 339                 cx231xx_err(DRIVER_NAME "urb resubmit failed (error=%i)\n",
 340                             urb->status);
 341         }
 342 }
 343
 344 /*
 345  * Stop and Deallocate URBs
 346  */
 347 void cx231xx_uninit_vbi_isoc(struct cx231xx *dev)
 348 {
 349         struct urb *urb;
 350         int i;
 351
 352         cx231xx_info(DRIVER_NAME "cx231xx: called cx231xx_uninit_vbi_isoc\n");
 353
 354         dev->vbi_mode.bulk_ctl.nfields = -1;
 355         for (i = 0; i < dev->vbi_mode.bulk_ctl.num_bufs; i++) {
 356                 urb = dev->vbi_mode.bulk_ctl.urb[i];
 357                 if (urb) {
 358                         if (!irqs_disabled())
 359                                 usb_kill_urb(urb);
 360                         else
 361                                 usb_unlink_urb(urb);
 362
 363                         if (dev->vbi_mode.bulk_ctl.transfer_buffer[i]) {
 364
 365                                 kfree(dev->vbi_mode.bulk_ctl.
 366                                       transfer_buffer[i]);
 367                                 dev->vbi_mode.bulk_ctl.transfer_buffer[i] =
 368                                     NULL;
 369                         }
 370                         usb_free_urb(urb);
 371                         dev->vbi_mode.bulk_ctl.urb[i] = NULL;
 372                 }
 373                 dev->vbi_mode.bulk_ctl.transfer_buffer[i] = NULL;
 374         }
 375
 376         kfree(dev->vbi_mode.bulk_ctl.urb);
 377         kfree(dev->vbi_mode.bulk_ctl.transfer_buffer);
 378
 379         dev->vbi_mode.bulk_ctl.urb = NULL;
 380         dev->vbi_mode.bulk_ctl.transfer_buffer = NULL;
 381         dev->vbi_mode.bulk_ctl.num_bufs = 0;
 382
 383         cx231xx_capture_start(dev, 0, Vbi);
 384 }
 385 EXPORT_SYMBOL_GPL(cx231xx_uninit_vbi_isoc);
 386
 387 /*
 388  * Allocate URBs and start IRQ
 389  */
 390 int cx231xx_init_vbi_isoc(struct cx231xx *dev, int max_packets,
 391                           int num_bufs, int max_pkt_size,
 392                           int (*bulk_copy) (struct cx231xx *dev,
 393                                             struct urb *urb))
 394 {
 395         struct cx231xx_dmaqueue *dma_q = &dev->vbi_mode.vidq;
 396         int i;
 397         int sb_size, pipe;
 398         struct urb *urb;
 399         int rc;
 400
 401         cx231xx_info(DRIVER_NAME "cx231xx: called cx231xx_prepare_isoc\n");
 402
 403         /* De-allocates all pending stuff */
 404         cx231xx_uninit_vbi_isoc(dev);
 405
 406         /* clear if any halt */
 407         usb_clear_halt(dev->udev,
 408                        usb_rcvbulkpipe(dev->udev,
 409                                        dev->vbi_mode.end_point_addr));
 410
 411         dev->vbi_mode.bulk_ctl.bulk_copy = bulk_copy;
 412         dev->vbi_mode.bulk_ctl.num_bufs = num_bufs;
 413         dma_q->pos = 0;
 414         dma_q->is_partial_line = 0;
 415         dma_q->last_sav = 0;
 416         dma_q->current_field = -1;
 417         dma_q->bytes_left_in_line = dev->width << 1;
 418         dma_q->lines_per_field = ((dev->norm & V4L2_STD_625_50) ?
 419                                   PAL_VBI_LINES : NTSC_VBI_LINES);
 420         dma_q->lines_completed = 0;
 421         for (i = 0; i < 8; i++)
 422                 dma_q->partial_buf[i] = 0;
 423
 424         dev->vbi_mode.bulk_ctl.urb = kzalloc(sizeof(void *) * num_bufs,
 425                                              GFP_KERNEL);
 426         if (!dev->vbi_mode.bulk_ctl.urb) {
 427                 cx231xx_errdev("cannot alloc memory for usb buffers\n");
 428                 return -ENOMEM;
 429         }
 430
 431         dev->vbi_mode.bulk_ctl.transfer_buffer =
 432             kzalloc(sizeof(void *) * num_bufs, GFP_KERNEL);
 433         if (!dev->vbi_mode.bulk_ctl.transfer_buffer) {
 434                 cx231xx_errdev("cannot allocate memory for usbtransfer\n");
 435                 kfree(dev->vbi_mode.bulk_ctl.urb);
 436                 return -ENOMEM;
 437         }
 438
 439         dev->vbi_mode.bulk_ctl.max_pkt_size = max_pkt_size;
 440         dev->vbi_mode.bulk_ctl.buf = NULL;
 441
 442         sb_size = max_packets * dev->vbi_mode.bulk_ctl.max_pkt_size;
 443
 444         /* allocate urbs and transfer buffers */
 445         for (i = 0; i < dev->vbi_mode.bulk_ctl.num_bufs; i++) {
 446
 447                 urb = usb_alloc_urb(0, GFP_KERNEL);
 448                 if (!urb) {
 449                         cx231xx_err(DRIVER_NAME
 450                                     ": cannot alloc bulk_ctl.urb %i\n", i);
 451                         cx231xx_uninit_vbi_isoc(dev);
 452                         return -ENOMEM;
 453                 }
 454                 dev->vbi_mode.bulk_ctl.urb[i] = urb;
 455                 urb->transfer_flags = 0;
 456
 457                 dev->vbi_mode.bulk_ctl.transfer_buffer[i] =
 458                     kzalloc(sb_size, GFP_KERNEL);
 459                 if (!dev->vbi_mode.bulk_ctl.transfer_buffer[i]) {
 460                         cx231xx_err(DRIVER_NAME
 461                                     ": unable to allocate %i bytes for transfer"
 462                                     " buffer %i%s\n", sb_size, i,
 463                                     in_interrupt() ? " while in int" : "");
 464                         cx231xx_uninit_vbi_isoc(dev);
 465                         return -ENOMEM;
 466                 }
 467
 468                 pipe = usb_rcvbulkpipe(dev->udev, dev->vbi_mode.end_point_addr);
 469                 usb_fill_bulk_urb(urb, dev->udev, pipe,
 470                                   dev->vbi_mode.bulk_ctl.transfer_buffer[i],
 471                                   sb_size, cx231xx_irq_vbi_callback, dma_q);
 472         }
 473
 474         init_waitqueue_head(&dma_q->wq);
 475
 476         /* submit urbs and enables IRQ */
 477         for (i = 0; i < dev->vbi_mode.bulk_ctl.num_bufs; i++) {
 478                 rc = usb_submit_urb(dev->vbi_mode.bulk_ctl.urb[i], GFP_ATOMIC);
 479                 if (rc) {
 480                         cx231xx_err(DRIVER_NAME
 481                                     ": submit of urb %i failed (error=%i)\n", i,
 482                                     rc);
 483                         cx231xx_uninit_vbi_isoc(dev);
 484                         return rc;
 485                 }
 486         }
 487
 488         cx231xx_capture_start(dev, 1, Vbi);
 489
 490         return 0;
 491 }
 492 EXPORT_SYMBOL_GPL(cx231xx_init_vbi_isoc);
 493
 494 u32 cx231xx_get_vbi_line(struct cx231xx *dev, struct cx231xx_dmaqueue *dma_q,
 495                          u8 sav_eav, u8 *p_buffer, u32 buffer_size)
 496 {
 497         u32 bytes_copied = 0;
 498         int current_field = -1;
 499
 500         switch (sav_eav) {
 501
 502         case SAV_VBI_FIELD1:
 503                 current_field = 1;
 504                 break;
 505
 506         case SAV_VBI_FIELD2:
 507                 current_field = 2;
 508                 break;
 509         default:
 510                 break;
 511         }
 512
 513         if (current_field < 0)
 514                 return bytes_copied;
 515
 516         dma_q->last_sav = sav_eav;
 517
 518         bytes_copied =
 519             cx231xx_copy_vbi_line(dev, dma_q, p_buffer, buffer_size,
 520                                   current_field);
 521
 522         return bytes_copied;
 523 }
 524
 525 /*
 526  * Announces that a buffer were filled and request the next
 527  */
 528 static inline void vbi_buffer_filled(struct cx231xx *dev,
 529                                      struct cx231xx_dmaqueue *dma_q,
 530                                      struct cx231xx_buffer *buf)
 531 {
 532         /* Advice that buffer was filled */
 533         /* cx231xx_info(DRIVER_NAME "[%p/%d] wakeup\n", buf, buf->vb.i); */
 534
 535         buf->vb.state = VIDEOBUF_DONE;
 536         buf->vb.field_count++;
 537         do_gettimeofday(&buf->vb.ts);
 538
 539         dev->vbi_mode.bulk_ctl.buf = NULL;
 540
 541         list_del(&buf->vb.queue);
 542         wake_up(&buf->vb.done);
 543 }
 544
 545 u32 cx231xx_copy_vbi_line(struct cx231xx *dev, struct cx231xx_dmaqueue *dma_q,
 546                           u8 *p_line, u32 length, int field_number)
 547 {
 548         u32 bytes_to_copy;
 549         struct cx231xx_buffer *buf;
 550         u32 _line_size = dev->width * 2;
 551
 552         if (dma_q->current_field == -1) {
 553                 /* Just starting up */
 554                 cx231xx_reset_vbi_buffer(dev, dma_q);
 555         }
 556
 557         if (dma_q->current_field != field_number)
 558                 dma_q->lines_completed = 0;
 559
 560         /* get the buffer pointer */
 561         buf = dev->vbi_mode.bulk_ctl.buf;
 562
 563         /* Remember the field number for next time */
 564         dma_q->current_field = field_number;
 565
 566         bytes_to_copy = dma_q->bytes_left_in_line;
 567         if (bytes_to_copy > length)
 568                 bytes_to_copy = length;
 569
 570         if (dma_q->lines_completed >= dma_q->lines_per_field) {
 571                 dma_q->bytes_left_in_line -= bytes_to_copy;
 572                 dma_q->is_partial_line =
 573                     (dma_q->bytes_left_in_line == 0) ? 0 : 1;
 574                 return 0;
 575         }
 576
 577         dma_q->is_partial_line = 1;
 578
 579         /* If we don't have a buffer, just return the number of bytes we would
 580            have copied if we had a buffer. */
 581         if (!buf) {
 582                 dma_q->bytes_left_in_line -= bytes_to_copy;
 583                 dma_q->is_partial_line =
 584                     (dma_q->bytes_left_in_line == 0) ? 0 : 1;
 585                 return bytes_to_copy;
 586         }
 587
 588         /* copy the data to video buffer */
 589         cx231xx_do_vbi_copy(dev, dma_q, p_line, bytes_to_copy);
 590
 591         dma_q->pos += bytes_to_copy;
 592         dma_q->bytes_left_in_line -= bytes_to_copy;
 593
 594         if (dma_q->bytes_left_in_line == 0) {
 595
 596                 dma_q->bytes_left_in_line = _line_size;
 597                 dma_q->lines_completed++;
 598                 dma_q->is_partial_line = 0;
 599
 600                 if (cx231xx_is_vbi_buffer_done(dev, dma_q) && buf) {
 601
 602                         vbi_buffer_filled(dev, dma_q, buf);
 603
 604                         dma_q->pos = 0;
 605                         dma_q->lines_completed = 0;
 606                         cx231xx_reset_vbi_buffer(dev, dma_q);
 607                 }
 608         }
 609
 610         return bytes_to_copy;
 611 }
 612
 613 /*
 614  * video-buf generic routine to get the next available buffer
 615  */
 616 static inline void get_next_vbi_buf(struct cx231xx_dmaqueue *dma_q,
 617                                     struct cx231xx_buffer **buf)
 618 {
 619         struct cx231xx_video_mode *vmode =
 620             container_of(dma_q, struct cx231xx_video_mode, vidq);
 621         struct cx231xx *dev = container_of(vmode, struct cx231xx, vbi_mode);
 622         char *outp;
 623
 624         if (list_empty(&dma_q->active)) {
 625                 cx231xx_err(DRIVER_NAME ": No active queue to serve\n");
 626                 dev->vbi_mode.bulk_ctl.buf = NULL;
 627                 *buf = NULL;
 628                 return;
 629         }
 630
 631         /* Get the next buffer */
 632         *buf = list_entry(dma_q->active.next, struct cx231xx_buffer, vb.queue);
 633
 634         /* Cleans up buffer - Usefull for testing for frame/URB loss */
 635         outp = videobuf_to_vmalloc(&(*buf)->vb);
 636         memset(outp, 0, (*buf)->vb.size);
 637
 638         dev->vbi_mode.bulk_ctl.buf = *buf;
 639
 640         return;
 641 }
 642
 643 void cx231xx_reset_vbi_buffer(struct cx231xx *dev,
 644                               struct cx231xx_dmaqueue *dma_q)
 645 {
 646         struct cx231xx_buffer *buf;
 647
 648         buf = dev->vbi_mode.bulk_ctl.buf;
 649
 650         if (buf == NULL) {
 651                 /* first try to get the buffer */
 652                 get_next_vbi_buf(dma_q, &buf);
 653
 654                 dma_q->pos = 0;
 655                 dma_q->current_field = -1;
 656         }
 657
 658         dma_q->bytes_left_in_line = dev->width << 1;
 659         dma_q->lines_completed = 0;
 660 }
 661
 662 int cx231xx_do_vbi_copy(struct cx231xx *dev, struct cx231xx_dmaqueue *dma_q,
 663                         u8 *p_buffer, u32 bytes_to_copy)
 664 {
 665         u8 *p_out_buffer = NULL;
 666         u32 current_line_bytes_copied = 0;
 667         struct cx231xx_buffer *buf;
 668         u32 _line_size = dev->width << 1;
 669         void *startwrite;
 670         int offset, lencopy;
 671
 672         buf = dev->vbi_mode.bulk_ctl.buf;
 673
 674         if (buf == NULL)
 675                 return -EINVAL;
 676
 677         p_out_buffer = videobuf_to_vmalloc(&buf->vb);
 678
 679         if (dma_q->bytes_left_in_line != _line_size) {
 680                 current_line_bytes_copied =
 681                     _line_size - dma_q->bytes_left_in_line;
 682         }
 683
 684         offset = (dma_q->lines_completed * _line_size) +
 685                  current_line_bytes_copied;
 686
 687         if (dma_q->current_field == 2) {
 688                 /* Populate the second half of the frame */
 689                 offset += (dev->width * 2 * dma_q->lines_per_field);
 690         }
 691
 692         /* prepare destination address */
 693         startwrite = p_out_buffer + offset;
 694
 695         lencopy = dma_q->bytes_left_in_line > bytes_to_copy ?
 696                   bytes_to_copy : dma_q->bytes_left_in_line;
 697
 698         memcpy(startwrite, p_buffer, lencopy);
 699
 700         return 0;
 701 }
 702
 703 u8 cx231xx_is_vbi_buffer_done(struct cx231xx *dev,
 704                               struct cx231xx_dmaqueue *dma_q)
 705 {
 706         u32 height = 0;
 707
 708         height = ((dev->norm & V4L2_STD_625_50) ?
 709                   PAL_VBI_LINES : NTSC_VBI_LINES);
 710         if (dma_q->lines_completed == height && dma_q->current_field == 2)
 711                 return 1;
 712         else
 713                 return 0;
 714 }