LXR linux/drivers/media/usb/cx231xx/cx231xx-vbi.c

   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3   cx231xx_vbi.c - driver for Conexant Cx23100/101/102 USB video capture devices
   4
   5   Copyright (C) 2008 <srinivasa.deevi at conexant dot com>
   6        Based on cx88 driver
   7
   8 */
   9
  10#include "cx231xx.h"
  11#include <linux/init.h>
  12#include <linux/list.h>
  13#include <linux/module.h>
  14#include <linux/kernel.h>
  15#include <linux/bitmap.h>
  16#include <linux/i2c.h>
  17#include <linux/mm.h>
  18#include <linux/mutex.h>
  19#include <linux/slab.h>
  20
  21#include <media/v4l2-common.h>
  22#include <media/v4l2-ioctl.h>
  23#include <media/drv-intf/msp3400.h>
  24#include <media/tuner.h>
  25
  26#include "cx231xx-vbi.h"
  27
  28static inline void print_err_status(struct cx231xx *dev, int packet, int status)
  29{
  30        char *errmsg = "Unknown";
  31
  32        switch (status) {
  33        case -ENOENT:
  34                errmsg = "unlinked synchronously";
  35                break;
  36        case -ECONNRESET:
  37                errmsg = "unlinked asynchronously";
  38                break;
  39        case -ENOSR:
  40                errmsg = "Buffer error (overrun)";
  41                break;
  42        case -EPIPE:
  43                errmsg = "Stalled (device not responding)";
  44                break;
  45        case -EOVERFLOW:
  46                errmsg = "Babble (bad cable?)";
  47                break;
  48        case -EPROTO:
  49                errmsg = "Bit-stuff error (bad cable?)";
  50                break;
  51        case -EILSEQ:
  52                errmsg = "CRC/Timeout (could be anything)";
  53                break;
  54        case -ETIME:
  55                errmsg = "Device does not respond";
  56                break;
  57        }
  58        if (packet < 0) {
  59                dev_err(dev->dev,
  60                        "URB status %d [%s].\n", status, errmsg);
  61        } else {
  62                dev_err(dev->dev,
  63                        "URB packet %d, status %d [%s].\n",
  64                        packet, status, errmsg);
  65        }
  66}
  67
  68/*
  69 * Controls the isoc copy of each urb packet
  70 */
  71static inline int cx231xx_isoc_vbi_copy(struct cx231xx *dev, struct urb *urb)
  72{
  73        struct cx231xx_dmaqueue *dma_q = urb->context;
  74        int rc = 1;
  75        unsigned char *p_buffer;
  76        u32 bytes_parsed = 0, buffer_size = 0;
  77        u8 sav_eav = 0;
  78
  79        if (!dev)
  80                return 0;
  81
  82        if (dev->state & DEV_DISCONNECTED)
  83                return 0;
  84
  85        if (urb->status < 0) {
  86                print_err_status(dev, -1, urb->status);
  87                if (urb->status == -ENOENT)
  88                        return 0;
  89        }
  90
  91        /* get buffer pointer and length */
  92        p_buffer = urb->transfer_buffer;
  93        buffer_size = urb->actual_length;
  94
  95        if (buffer_size > 0) {
  96                bytes_parsed = 0;
  97
  98                if (dma_q->is_partial_line) {
  99                        /* Handle the case where we were working on a partial
 100                           line */
 101                        sav_eav = dma_q->last_sav;
 102                } else {
 103                        /* Check for a SAV/EAV overlapping the
 104                           buffer boundary */
 105
 106                        sav_eav = cx231xx_find_boundary_SAV_EAV(p_buffer,
 107                                                          dma_q->partial_buf,
 108                                                          &bytes_parsed);
 109                }
 110
 111                sav_eav &= 0xF0;
 112                /* Get the first line if we have some portion of an SAV/EAV from
 113                   the last buffer or a partial line */
 114                if (sav_eav) {
 115                        bytes_parsed += cx231xx_get_vbi_line(dev, dma_q,
 116                                sav_eav,                       /* SAV/EAV */
 117                                p_buffer + bytes_parsed,       /* p_buffer */
 118                                buffer_size - bytes_parsed);   /* buffer size */
 119                }
 120
 121                /* Now parse data that is completely in this buffer */
 122                dma_q->is_partial_line = 0;
 123
 124                while (bytes_parsed < buffer_size) {
 125                        u32 bytes_used = 0;
 126
 127                        sav_eav = cx231xx_find_next_SAV_EAV(
 128                                p_buffer + bytes_parsed,        /* p_buffer */
 129                                buffer_size - bytes_parsed, /* buffer size */
 130                                &bytes_used);   /* bytes used to get SAV/EAV */
 131
 132                        bytes_parsed += bytes_used;
 133
 134                        sav_eav &= 0xF0;
 135                        if (sav_eav && (bytes_parsed < buffer_size)) {
 136                                bytes_parsed += cx231xx_get_vbi_line(dev,
 137                                        dma_q, sav_eav, /* SAV/EAV */
 138                                        p_buffer+bytes_parsed, /* p_buffer */
 139                                        buffer_size-bytes_parsed);/*buf size*/
 140                        }
 141                }
 142
 143                /* Save the last four bytes of the buffer so we can
 144                check the buffer boundary condition next time */
 145                memcpy(dma_q->partial_buf, p_buffer + buffer_size - 4, 4);
 146                bytes_parsed = 0;
 147        }
 148
 149        return rc;
 150}
 151
 152/* ------------------------------------------------------------------
 153        Vbi buf operations
 154   ------------------------------------------------------------------*/
 155
 156static int
 157vbi_buffer_setup(struct videobuf_queue *vq, unsigned int *count,
 158                 unsigned int *size)
 159{
 160        struct cx231xx_fh *fh = vq->priv_data;
 161        struct cx231xx *dev = fh->dev;
 162        u32 height = 0;
 163
 164        height = ((dev->norm & V4L2_STD_625_50) ?
 165                  PAL_VBI_LINES : NTSC_VBI_LINES);
 166
 167        *size = (dev->width * height * 2 * 2);
 168        if (0 == *count)
 169                *count = CX231XX_DEF_VBI_BUF;
 170
 171        if (*count < CX231XX_MIN_BUF)
 172                *count = CX231XX_MIN_BUF;
 173
 174        return 0;
 175}
 176
 177/* This is called *without* dev->slock held; please keep it that way */
 178static void free_buffer(struct videobuf_queue *vq, struct cx231xx_buffer *buf)
 179{
 180        struct cx231xx_fh *fh = vq->priv_data;
 181        struct cx231xx *dev = fh->dev;
 182        unsigned long flags = 0;
 183        BUG_ON(in_interrupt());
 184
 185        /* We used to wait for the buffer to finish here, but this didn't work
 186           because, as we were keeping the state as VIDEOBUF_QUEUED,
 187           videobuf_queue_cancel marked it as finished for us.
 188           (Also, it could wedge forever if the hardware was misconfigured.)
 189
 190           This should be safe; by the time we get here, the buffer isn't
 191           queued anymore. If we ever start marking the buffers as
 192           VIDEOBUF_ACTIVE, it won't be, though.
 193         */
 194        spin_lock_irqsave(&dev->vbi_mode.slock, flags);
 195        if (dev->vbi_mode.bulk_ctl.buf == buf)
 196                dev->vbi_mode.bulk_ctl.buf = NULL;
 197        spin_unlock_irqrestore(&dev->vbi_mode.slock, flags);
 198
 199        videobuf_vmalloc_free(&buf->vb);
 200        buf->vb.state = VIDEOBUF_NEEDS_INIT;
 201}
 202
 203static int
 204vbi_buffer_prepare(struct videobuf_queue *vq, struct videobuf_buffer *vb,
 205                   enum v4l2_field field)
 206{
 207        struct cx231xx_fh *fh = vq->priv_data;
 208        struct cx231xx_buffer *buf =
 209            container_of(vb, struct cx231xx_buffer, vb);
 210        struct cx231xx *dev = fh->dev;
 211        int rc = 0, urb_init = 0;
 212        u32 height = 0;
 213
 214        height = ((dev->norm & V4L2_STD_625_50) ?
 215                  PAL_VBI_LINES : NTSC_VBI_LINES);
 216        buf->vb.size = ((dev->width << 1) * height * 2);
 217
 218        if (0 != buf->vb.baddr && buf->vb.bsize < buf->vb.size)
 219                return -EINVAL;
 220
 221        buf->vb.width = dev->width;
 222        buf->vb.height = height;
 223        buf->vb.field = field;
 224        buf->vb.field = V4L2_FIELD_SEQ_TB;
 225
 226        if (VIDEOBUF_NEEDS_INIT == buf->vb.state) {
 227                rc = videobuf_iolock(vq, &buf->vb, NULL);
 228                if (rc < 0)
 229                        goto fail;
 230        }
 231
 232        if (!dev->vbi_mode.bulk_ctl.num_bufs)
 233                urb_init = 1;
 234
 235        if (urb_init) {
 236                rc = cx231xx_init_vbi_isoc(dev, CX231XX_NUM_VBI_PACKETS,
 237                                           CX231XX_NUM_VBI_BUFS,
 238                                           dev->vbi_mode.alt_max_pkt_size[0],
 239                                           cx231xx_isoc_vbi_copy);
 240                if (rc < 0)
 241                        goto fail;
 242        }
 243
 244        buf->vb.state = VIDEOBUF_PREPARED;
 245        return 0;
 246
 247fail:
 248        free_buffer(vq, buf);
 249        return rc;
 250}
 251
 252static void
 253vbi_buffer_queue(struct videobuf_queue *vq, struct videobuf_buffer *vb)
 254{
 255        struct cx231xx_buffer *buf =
 256            container_of(vb, struct cx231xx_buffer, vb);
 257        struct cx231xx_fh *fh = vq->priv_data;
 258        struct cx231xx *dev = fh->dev;
 259        struct cx231xx_dmaqueue *vidq = &dev->vbi_mode.vidq;
 260
 261        buf->vb.state = VIDEOBUF_QUEUED;
 262        list_add_tail(&buf->vb.queue, &vidq->active);
 263
 264}
 265
 266static void vbi_buffer_release(struct videobuf_queue *vq,
 267                               struct videobuf_buffer *vb)
 268{
 269        struct cx231xx_buffer *buf =
 270            container_of(vb, struct cx231xx_buffer, vb);
 271
 272
 273        free_buffer(vq, buf);
 274}
 275
 276const struct videobuf_queue_ops cx231xx_vbi_qops = {
 277        .buf_setup   = vbi_buffer_setup,
 278        .buf_prepare = vbi_buffer_prepare,
 279        .buf_queue   = vbi_buffer_queue,
 280        .buf_release = vbi_buffer_release,
 281};
 282
 283/* ------------------------------------------------------------------
 284        URB control
 285   ------------------------------------------------------------------*/
 286
 287/*
 288 * IRQ callback, called by URB callback
 289 */
 290static void cx231xx_irq_vbi_callback(struct urb *urb)
 291{
 292        struct cx231xx_dmaqueue *dma_q = urb->context;
 293        struct cx231xx_video_mode *vmode =
 294            container_of(dma_q, struct cx231xx_video_mode, vidq);
 295        struct cx231xx *dev = container_of(vmode, struct cx231xx, vbi_mode);
 296        unsigned long flags;
 297
 298        switch (urb->status) {
 299        case 0:         /* success */
 300        case -ETIMEDOUT:        /* NAK */
 301                break;
 302        case -ECONNRESET:       /* kill */
 303        case -ENOENT:
 304        case -ESHUTDOWN:
 305                return;
 306        default:                /* error */
 307                dev_err(dev->dev,
 308                        "urb completion error %d.\n", urb->status);
 309                break;
 310        }
 311
 312        /* Copy data from URB */
 313        spin_lock_irqsave(&dev->vbi_mode.slock, flags);
 314        dev->vbi_mode.bulk_ctl.bulk_copy(dev, urb);
 315        spin_unlock_irqrestore(&dev->vbi_mode.slock, flags);
 316
 317        /* Reset status */
 318        urb->status = 0;
 319
 320        urb->status = usb_submit_urb(urb, GFP_ATOMIC);
 321        if (urb->status) {
 322                dev_err(dev->dev, "urb resubmit failed (error=%i)\n",
 323                        urb->status);
 324        }
 325}
 326
 327/*
 328 * Stop and Deallocate URBs
 329 */
 330void cx231xx_uninit_vbi_isoc(struct cx231xx *dev)
 331{
 332        struct urb *urb;
 333        int i;
 334
 335        dev_dbg(dev->dev, "called cx231xx_uninit_vbi_isoc\n");
 336
 337        dev->vbi_mode.bulk_ctl.nfields = -1;
 338        for (i = 0; i < dev->vbi_mode.bulk_ctl.num_bufs; i++) {
 339                urb = dev->vbi_mode.bulk_ctl.urb[i];
 340                if (urb) {
 341                        if (!irqs_disabled())
 342                                usb_kill_urb(urb);
 343                        else
 344                                usb_unlink_urb(urb);
 345
 346                        if (dev->vbi_mode.bulk_ctl.transfer_buffer[i]) {
 347
 348                                kfree(dev->vbi_mode.bulk_ctl.
 349                                      transfer_buffer[i]);
 350                                dev->vbi_mode.bulk_ctl.transfer_buffer[i] =
 351                                    NULL;
 352                        }
 353                        usb_free_urb(urb);
 354                        dev->vbi_mode.bulk_ctl.urb[i] = NULL;
 355                }
 356                dev->vbi_mode.bulk_ctl.transfer_buffer[i] = NULL;
 357        }
 358
 359        kfree(dev->vbi_mode.bulk_ctl.urb);
 360        kfree(dev->vbi_mode.bulk_ctl.transfer_buffer);
 361
 362        dev->vbi_mode.bulk_ctl.urb = NULL;
 363        dev->vbi_mode.bulk_ctl.transfer_buffer = NULL;
 364        dev->vbi_mode.bulk_ctl.num_bufs = 0;
 365
 366        cx231xx_capture_start(dev, 0, Vbi);
 367}
 368EXPORT_SYMBOL_GPL(cx231xx_uninit_vbi_isoc);
 369
 370/*
 371 * Allocate URBs and start IRQ
 372 */
 373int cx231xx_init_vbi_isoc(struct cx231xx *dev, int max_packets,
 374                          int num_bufs, int max_pkt_size,
 375                          int (*bulk_copy) (struct cx231xx *dev,
 376                                            struct urb *urb))
 377{
 378        struct cx231xx_dmaqueue *dma_q = &dev->vbi_mode.vidq;
 379        int i;
 380        int sb_size, pipe;
 381        struct urb *urb;
 382        int rc;
 383
 384        dev_dbg(dev->dev, "called cx231xx_vbi_isoc\n");
 385
 386        /* De-allocates all pending stuff */
 387        cx231xx_uninit_vbi_isoc(dev);
 388
 389        /* clear if any halt */
 390        usb_clear_halt(dev->udev,
 391                       usb_rcvbulkpipe(dev->udev,
 392                                       dev->vbi_mode.end_point_addr));
 393
 394        dev->vbi_mode.bulk_ctl.bulk_copy = bulk_copy;
 395        dev->vbi_mode.bulk_ctl.num_bufs = num_bufs;
 396        dma_q->pos = 0;
 397        dma_q->is_partial_line = 0;
 398        dma_q->last_sav = 0;
 399        dma_q->current_field = -1;
 400        dma_q->bytes_left_in_line = dev->width << 1;
 401        dma_q->lines_per_field = ((dev->norm & V4L2_STD_625_50) ?
 402                                  PAL_VBI_LINES : NTSC_VBI_LINES);
 403        dma_q->lines_completed = 0;
 404        for (i = 0; i < 8; i++)
 405                dma_q->partial_buf[i] = 0;
 406
 407        dev->vbi_mode.bulk_ctl.urb = kcalloc(num_bufs, sizeof(void *),
 408                                             GFP_KERNEL);
 409        if (!dev->vbi_mode.bulk_ctl.urb) {
 410                dev_err(dev->dev,
 411                        "cannot alloc memory for usb buffers\n");
 412                return -ENOMEM;
 413        }
 414
 415        dev->vbi_mode.bulk_ctl.transfer_buffer =
 416            kcalloc(num_bufs, sizeof(void *), GFP_KERNEL);
 417        if (!dev->vbi_mode.bulk_ctl.transfer_buffer) {
 418                dev_err(dev->dev,
 419                        "cannot allocate memory for usbtransfer\n");
 420                kfree(dev->vbi_mode.bulk_ctl.urb);
 421                return -ENOMEM;
 422        }
 423
 424        dev->vbi_mode.bulk_ctl.max_pkt_size = max_pkt_size;
 425        dev->vbi_mode.bulk_ctl.buf = NULL;
 426
 427        sb_size = max_packets * dev->vbi_mode.bulk_ctl.max_pkt_size;
 428
 429        /* allocate urbs and transfer buffers */
 430        for (i = 0; i < dev->vbi_mode.bulk_ctl.num_bufs; i++) {
 431
 432                urb = usb_alloc_urb(0, GFP_KERNEL);
 433                if (!urb) {
 434                        cx231xx_uninit_vbi_isoc(dev);
 435                        return -ENOMEM;
 436                }
 437                dev->vbi_mode.bulk_ctl.urb[i] = urb;
 438                urb->transfer_flags = 0;
 439
 440                dev->vbi_mode.bulk_ctl.transfer_buffer[i] =
 441                    kzalloc(sb_size, GFP_KERNEL);
 442                if (!dev->vbi_mode.bulk_ctl.transfer_buffer[i]) {
 443                        dev_err(dev->dev,
 444                                "unable to allocate %i bytes for transfer buffer %i%s\n",
 445                                sb_size, i,
 446                                in_interrupt() ? " while in int" : "");
 447                        cx231xx_uninit_vbi_isoc(dev);
 448                        return -ENOMEM;
 449                }
 450
 451                pipe = usb_rcvbulkpipe(dev->udev, dev->vbi_mode.end_point_addr);
 452                usb_fill_bulk_urb(urb, dev->udev, pipe,
 453                                  dev->vbi_mode.bulk_ctl.transfer_buffer[i],
 454                                  sb_size, cx231xx_irq_vbi_callback, dma_q);
 455        }
 456
 457        init_waitqueue_head(&dma_q->wq);
 458
 459        /* submit urbs and enables IRQ */
 460        for (i = 0; i < dev->vbi_mode.bulk_ctl.num_bufs; i++) {
 461                rc = usb_submit_urb(dev->vbi_mode.bulk_ctl.urb[i], GFP_ATOMIC);
 462                if (rc) {
 463                        dev_err(dev->dev,
 464                                "submit of urb %i failed (error=%i)\n", i, rc);
 465                        cx231xx_uninit_vbi_isoc(dev);
 466                        return rc;
 467                }
 468        }
 469
 470        cx231xx_capture_start(dev, 1, Vbi);
 471
 472        return 0;
 473}
 474EXPORT_SYMBOL_GPL(cx231xx_init_vbi_isoc);
 475
 476u32 cx231xx_get_vbi_line(struct cx231xx *dev, struct cx231xx_dmaqueue *dma_q,
 477                         u8 sav_eav, u8 *p_buffer, u32 buffer_size)
 478{
 479        u32 bytes_copied = 0;
 480        int current_field = -1;
 481
 482        switch (sav_eav) {
 483
 484        case SAV_VBI_FIELD1:
 485                current_field = 1;
 486                break;
 487
 488        case SAV_VBI_FIELD2:
 489                current_field = 2;
 490                break;
 491        default:
 492                break;
 493        }
 494
 495        if (current_field < 0)
 496                return bytes_copied;
 497
 498        dma_q->last_sav = sav_eav;
 499
 500        bytes_copied =
 501            cx231xx_copy_vbi_line(dev, dma_q, p_buffer, buffer_size,
 502                                  current_field);
 503
 504        return bytes_copied;
 505}
 506
 507/*
 508 * Announces that a buffer were filled and request the next
 509 */
 510static inline void vbi_buffer_filled(struct cx231xx *dev,
 511                                     struct cx231xx_dmaqueue *dma_q,
 512                                     struct cx231xx_buffer *buf)
 513{
 514        /* Advice that buffer was filled */
 515        /* dev_dbg(dev->dev, "[%p/%d] wakeup\n", buf, buf->vb.i); */
 516
 517        buf->vb.state = VIDEOBUF_DONE;
 518        buf->vb.field_count++;
 519        buf->vb.ts = ktime_get_ns();
 520
 521        dev->vbi_mode.bulk_ctl.buf = NULL;
 522
 523        list_del(&buf->vb.queue);
 524        wake_up(&buf->vb.done);
 525}
 526
 527u32 cx231xx_copy_vbi_line(struct cx231xx *dev, struct cx231xx_dmaqueue *dma_q,
 528                          u8 *p_line, u32 length, int field_number)
 529{
 530        u32 bytes_to_copy;
 531        struct cx231xx_buffer *buf;
 532        u32 _line_size = dev->width * 2;
 533
 534        if (dma_q->current_field == -1) {
 535                /* Just starting up */
 536                cx231xx_reset_vbi_buffer(dev, dma_q);
 537        }
 538
 539        if (dma_q->current_field != field_number)
 540                dma_q->lines_completed = 0;
 541
 542        /* get the buffer pointer */
 543        buf = dev->vbi_mode.bulk_ctl.buf;
 544
 545        /* Remember the field number for next time */
 546        dma_q->current_field = field_number;
 547
 548        bytes_to_copy = dma_q->bytes_left_in_line;
 549        if (bytes_to_copy > length)
 550                bytes_to_copy = length;
 551
 552        if (dma_q->lines_completed >= dma_q->lines_per_field) {
 553                dma_q->bytes_left_in_line -= bytes_to_copy;
 554                dma_q->is_partial_line =
 555                    (dma_q->bytes_left_in_line == 0) ? 0 : 1;
 556                return 0;
 557        }
 558
 559        dma_q->is_partial_line = 1;
 560
 561        /* If we don't have a buffer, just return the number of bytes we would
 562           have copied if we had a buffer. */
 563        if (!buf) {
 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 bytes_to_copy;
 568        }
 569
 570        /* copy the data to video buffer */
 571        cx231xx_do_vbi_copy(dev, dma_q, p_line, bytes_to_copy);
 572
 573        dma_q->pos += bytes_to_copy;
 574        dma_q->bytes_left_in_line -= bytes_to_copy;
 575
 576        if (dma_q->bytes_left_in_line == 0) {
 577
 578                dma_q->bytes_left_in_line = _line_size;
 579                dma_q->lines_completed++;
 580                dma_q->is_partial_line = 0;
 581
 582                if (cx231xx_is_vbi_buffer_done(dev, dma_q) && buf) {
 583
 584                        vbi_buffer_filled(dev, dma_q, buf);
 585
 586                        dma_q->pos = 0;
 587                        dma_q->lines_completed = 0;
 588                        cx231xx_reset_vbi_buffer(dev, dma_q);
 589                }
 590        }
 591
 592        return bytes_to_copy;
 593}
 594
 595/*
 596 * video-buf generic routine to get the next available buffer
 597 */
 598static inline void get_next_vbi_buf(struct cx231xx_dmaqueue *dma_q,
 599                                    struct cx231xx_buffer **buf)
 600{
 601        struct cx231xx_video_mode *vmode =
 602            container_of(dma_q, struct cx231xx_video_mode, vidq);
 603        struct cx231xx *dev = container_of(vmode, struct cx231xx, vbi_mode);
 604        char *outp;
 605
 606        if (list_empty(&dma_q->active)) {
 607                dev_err(dev->dev, "No active queue to serve\n");
 608                dev->vbi_mode.bulk_ctl.buf = NULL;
 609                *buf = NULL;
 610                return;
 611        }
 612
 613        /* Get the next buffer */
 614        *buf = list_entry(dma_q->active.next, struct cx231xx_buffer, vb.queue);
 615
 616        /* Cleans up buffer - Useful for testing for frame/URB loss */
 617        outp = videobuf_to_vmalloc(&(*buf)->vb);
 618        memset(outp, 0, (*buf)->vb.size);
 619
 620        dev->vbi_mode.bulk_ctl.buf = *buf;
 621
 622        return;
 623}
 624
 625void cx231xx_reset_vbi_buffer(struct cx231xx *dev,
 626                              struct cx231xx_dmaqueue *dma_q)
 627{
 628        struct cx231xx_buffer *buf;
 629
 630        buf = dev->vbi_mode.bulk_ctl.buf;
 631
 632        if (buf == NULL) {
 633                /* first try to get the buffer */
 634                get_next_vbi_buf(dma_q, &buf);
 635
 636                dma_q->pos = 0;
 637                dma_q->current_field = -1;
 638        }
 639
 640        dma_q->bytes_left_in_line = dev->width << 1;
 641        dma_q->lines_completed = 0;
 642}
 643
 644int cx231xx_do_vbi_copy(struct cx231xx *dev, struct cx231xx_dmaqueue *dma_q,
 645                        u8 *p_buffer, u32 bytes_to_copy)
 646{
 647        u8 *p_out_buffer = NULL;
 648        u32 current_line_bytes_copied = 0;
 649        struct cx231xx_buffer *buf;
 650        u32 _line_size = dev->width << 1;
 651        void *startwrite;
 652        int offset, lencopy;
 653
 654        buf = dev->vbi_mode.bulk_ctl.buf;
 655
 656        if (buf == NULL)
 657                return -EINVAL;
 658
 659        p_out_buffer = videobuf_to_vmalloc(&buf->vb);
 660
 661        if (dma_q->bytes_left_in_line != _line_size) {
 662                current_line_bytes_copied =
 663                    _line_size - dma_q->bytes_left_in_line;
 664        }
 665
 666        offset = (dma_q->lines_completed * _line_size) +
 667                 current_line_bytes_copied;
 668
 669        if (dma_q->current_field == 2) {
 670                /* Populate the second half of the frame */
 671                offset += (dev->width * 2 * dma_q->lines_per_field);
 672        }
 673
 674        /* prepare destination address */
 675        startwrite = p_out_buffer + offset;
 676
 677        lencopy = dma_q->bytes_left_in_line > bytes_to_copy ?
 678                  bytes_to_copy : dma_q->bytes_left_in_line;
 679
 680        memcpy(startwrite, p_buffer, lencopy);
 681
 682        return 0;
 683}
 684
 685u8 cx231xx_is_vbi_buffer_done(struct cx231xx *dev,
 686                              struct cx231xx_dmaqueue *dma_q)
 687{
 688        u32 height = 0;
 689
 690        height = ((dev->norm & V4L2_STD_625_50) ?
 691                  PAL_VBI_LINES : NTSC_VBI_LINES);
 692        if (dma_q->lines_completed == height && dma_q->current_field == 2)
 693                return 1;
 694        else
 695                return 0;
 696}
 697