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
  28 static 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  */
  71 static 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
 156 static int vbi_queue_setup(struct vb2_queue *vq,
 157                            unsigned int *nbuffers, unsigned int *nplanes,
 158                            unsigned int sizes[], struct device *alloc_devs[])
 159 {
 160         struct cx231xx *dev = vb2_get_drv_priv(vq);
 161         u32 height = 0;
 162
 163         height = ((dev->norm & V4L2_STD_625_50) ?
 164                   PAL_VBI_LINES : NTSC_VBI_LINES);
 165
 166         *nplanes = 1;
 167         sizes[0] = (dev->width * height * 2 * 2);
 168         return 0;
 169 }
 170
 171 /* This is called *without* dev->slock held; please keep it that way */
 172 static int vbi_buf_prepare(struct vb2_buffer *vb)
 173 {
 174         struct cx231xx *dev = vb2_get_drv_priv(vb->vb2_queue);
 175         u32 height = 0;
 176         u32 size;
 177
 178         height = ((dev->norm & V4L2_STD_625_50) ?
 179                   PAL_VBI_LINES : NTSC_VBI_LINES);
 180         size = ((dev->width << 1) * height * 2);
 181
 182         if (vb2_plane_size(vb, 0) < size)
 183                 return -EINVAL;
 184         vb2_set_plane_payload(vb, 0, size);
 185         return 0;
 186 }
 187
 188 static void vbi_buf_queue(struct vb2_buffer *vb)
 189 {
 190         struct cx231xx *dev = vb2_get_drv_priv(vb->vb2_queue);
 191         struct cx231xx_buffer *buf =
 192             container_of(vb, struct cx231xx_buffer, vb.vb2_buf);
 193         struct cx231xx_dmaqueue *vidq = &dev->vbi_mode.vidq;
 194         unsigned long flags;
 195
 196         spin_lock_irqsave(&dev->vbi_mode.slock, flags);
 197         list_add_tail(&buf->list, &vidq->active);
 198         spin_unlock_irqrestore(&dev->vbi_mode.slock, flags);
 199 }
 200
 201 static void return_all_buffers(struct cx231xx *dev,
 202                                enum vb2_buffer_state state)
 203 {
 204         struct cx231xx_dmaqueue *vidq = &dev->vbi_mode.vidq;
 205         struct cx231xx_buffer *buf, *node;
 206         unsigned long flags;
 207
 208         spin_lock_irqsave(&dev->vbi_mode.slock, flags);
 209         dev->vbi_mode.bulk_ctl.buf = NULL;
 210         list_for_each_entry_safe(buf, node, &vidq->active, list) {
 211                 list_del(&buf->list);
 212                 vb2_buffer_done(&buf->vb.vb2_buf, state);
 213         }
 214         spin_unlock_irqrestore(&dev->vbi_mode.slock, flags);
 215 }
 216
 217 static int vbi_start_streaming(struct vb2_queue *vq, unsigned int count)
 218 {
 219         struct cx231xx *dev = vb2_get_drv_priv(vq);
 220         struct cx231xx_dmaqueue *vidq = &dev->vbi_mode.vidq;
 221         int ret;
 222
 223         vidq->sequence = 0;
 224         ret = cx231xx_init_vbi_isoc(dev, CX231XX_NUM_VBI_PACKETS,
 225                                     CX231XX_NUM_VBI_BUFS,
 226                                     dev->vbi_mode.alt_max_pkt_size[0],
 227                                     cx231xx_isoc_vbi_copy);
 228         if (ret)
 229                 return_all_buffers(dev, VB2_BUF_STATE_QUEUED);
 230         return ret;
 231 }
 232
 233 static void vbi_stop_streaming(struct vb2_queue *vq)
 234 {
 235         struct cx231xx *dev = vb2_get_drv_priv(vq);
 236
 237         return_all_buffers(dev, VB2_BUF_STATE_ERROR);
 238 }
 239
 240 struct vb2_ops cx231xx_vbi_qops = {
 241         .queue_setup = vbi_queue_setup,
 242         .buf_prepare = vbi_buf_prepare,
 243         .buf_queue = vbi_buf_queue,
 244         .start_streaming = vbi_start_streaming,
 245         .stop_streaming = vbi_stop_streaming,
 246 };
 247
 248 /* ------------------------------------------------------------------
 249         URB control
 250    ------------------------------------------------------------------*/
 251
 252 /*
 253  * IRQ callback, called by URB callback
 254  */
 255 static void cx231xx_irq_vbi_callback(struct urb *urb)
 256 {
 257         struct cx231xx_dmaqueue *dma_q = urb->context;
 258         struct cx231xx_video_mode *vmode =
 259             container_of(dma_q, struct cx231xx_video_mode, vidq);
 260         struct cx231xx *dev = container_of(vmode, struct cx231xx, vbi_mode);
 261         unsigned long flags;
 262
 263         switch (urb->status) {
 264         case 0:         /* success */
 265         case -ETIMEDOUT:        /* NAK */
 266                 break;
 267         case -ECONNRESET:       /* kill */
 268         case -ENOENT:
 269         case -ESHUTDOWN:
 270                 return;
 271         default:                /* error */
 272                 dev_err(dev->dev,
 273                         "urb completion error %d.\n", urb->status);
 274                 break;
 275         }
 276
 277         /* Copy data from URB */
 278         spin_lock_irqsave(&dev->vbi_mode.slock, flags);
 279         dev->vbi_mode.bulk_ctl.bulk_copy(dev, urb);
 280         spin_unlock_irqrestore(&dev->vbi_mode.slock, flags);
 281
 282         /* Reset status */
 283         urb->status = 0;
 284
 285         urb->status = usb_submit_urb(urb, GFP_ATOMIC);
 286         if (urb->status) {
 287                 dev_err(dev->dev, "urb resubmit failed (error=%i)\n",
 288                         urb->status);
 289         }
 290 }
 291
 292 /*
 293  * Stop and Deallocate URBs
 294  */
 295 void cx231xx_uninit_vbi_isoc(struct cx231xx *dev)
 296 {
 297         struct urb *urb;
 298         int i;
 299
 300         dev_dbg(dev->dev, "called cx231xx_uninit_vbi_isoc\n");
 301
 302         dev->vbi_mode.bulk_ctl.nfields = -1;
 303         for (i = 0; i < dev->vbi_mode.bulk_ctl.num_bufs; i++) {
 304                 urb = dev->vbi_mode.bulk_ctl.urb[i];
 305                 if (urb) {
 306                         if (!irqs_disabled())
 307                                 usb_kill_urb(urb);
 308                         else
 309                                 usb_unlink_urb(urb);
 310
 311                         if (dev->vbi_mode.bulk_ctl.transfer_buffer[i]) {
 312
 313                                 kfree(dev->vbi_mode.bulk_ctl.
 314                                       transfer_buffer[i]);
 315                                 dev->vbi_mode.bulk_ctl.transfer_buffer[i] =
 316                                     NULL;
 317                         }
 318                         usb_free_urb(urb);
 319                         dev->vbi_mode.bulk_ctl.urb[i] = NULL;
 320                 }
 321                 dev->vbi_mode.bulk_ctl.transfer_buffer[i] = NULL;
 322         }
 323
 324         kfree(dev->vbi_mode.bulk_ctl.urb);
 325         kfree(dev->vbi_mode.bulk_ctl.transfer_buffer);
 326
 327         dev->vbi_mode.bulk_ctl.urb = NULL;
 328         dev->vbi_mode.bulk_ctl.transfer_buffer = NULL;
 329         dev->vbi_mode.bulk_ctl.num_bufs = 0;
 330
 331         cx231xx_capture_start(dev, 0, Vbi);
 332 }
 333 EXPORT_SYMBOL_GPL(cx231xx_uninit_vbi_isoc);
 334
 335 /*
 336  * Allocate URBs and start IRQ
 337  */
 338 int cx231xx_init_vbi_isoc(struct cx231xx *dev, int max_packets,
 339                           int num_bufs, int max_pkt_size,
 340                           int (*bulk_copy) (struct cx231xx *dev,
 341                                             struct urb *urb))
 342 {
 343         struct cx231xx_dmaqueue *dma_q = &dev->vbi_mode.vidq;
 344         int i;
 345         int sb_size, pipe;
 346         struct urb *urb;
 347         int rc;
 348
 349         dev_dbg(dev->dev, "called cx231xx_vbi_isoc\n");
 350
 351         /* De-allocates all pending stuff */
 352         cx231xx_uninit_vbi_isoc(dev);
 353
 354         /* clear if any halt */
 355         usb_clear_halt(dev->udev,
 356                        usb_rcvbulkpipe(dev->udev,
 357                                        dev->vbi_mode.end_point_addr));
 358
 359         dev->vbi_mode.bulk_ctl.bulk_copy = bulk_copy;
 360         dev->vbi_mode.bulk_ctl.num_bufs = num_bufs;
 361         dma_q->pos = 0;
 362         dma_q->is_partial_line = 0;
 363         dma_q->last_sav = 0;
 364         dma_q->current_field = -1;
 365         dma_q->bytes_left_in_line = dev->width << 1;
 366         dma_q->lines_per_field = ((dev->norm & V4L2_STD_625_50) ?
 367                                   PAL_VBI_LINES : NTSC_VBI_LINES);
 368         dma_q->lines_completed = 0;
 369         for (i = 0; i < 8; i++)
 370                 dma_q->partial_buf[i] = 0;
 371
 372         dev->vbi_mode.bulk_ctl.urb = kcalloc(num_bufs, sizeof(void *),
 373                                              GFP_KERNEL);
 374         if (!dev->vbi_mode.bulk_ctl.urb) {
 375                 dev_err(dev->dev,
 376                         "cannot alloc memory for usb buffers\n");
 377                 return -ENOMEM;
 378         }
 379
 380         dev->vbi_mode.bulk_ctl.transfer_buffer =
 381             kcalloc(num_bufs, sizeof(void *), GFP_KERNEL);
 382         if (!dev->vbi_mode.bulk_ctl.transfer_buffer) {
 383                 dev_err(dev->dev,
 384                         "cannot allocate memory for usbtransfer\n");
 385                 kfree(dev->vbi_mode.bulk_ctl.urb);
 386                 return -ENOMEM;
 387         }
 388
 389         dev->vbi_mode.bulk_ctl.max_pkt_size = max_pkt_size;
 390         dev->vbi_mode.bulk_ctl.buf = NULL;
 391
 392         sb_size = max_packets * dev->vbi_mode.bulk_ctl.max_pkt_size;
 393
 394         /* allocate urbs and transfer buffers */
 395         for (i = 0; i < dev->vbi_mode.bulk_ctl.num_bufs; i++) {
 396
 397                 urb = usb_alloc_urb(0, GFP_KERNEL);
 398                 if (!urb) {
 399                         cx231xx_uninit_vbi_isoc(dev);
 400                         return -ENOMEM;
 401                 }
 402                 dev->vbi_mode.bulk_ctl.urb[i] = urb;
 403                 urb->transfer_flags = 0;
 404
 405                 dev->vbi_mode.bulk_ctl.transfer_buffer[i] =
 406                     kzalloc(sb_size, GFP_KERNEL);
 407                 if (!dev->vbi_mode.bulk_ctl.transfer_buffer[i]) {
 408                         dev_err(dev->dev,
 409                                 "unable to allocate %i bytes for transfer buffer %i\n",
 410                                 sb_size, i);
 411                         cx231xx_uninit_vbi_isoc(dev);
 412                         return -ENOMEM;
 413                 }
 414
 415                 pipe = usb_rcvbulkpipe(dev->udev, dev->vbi_mode.end_point_addr);
 416                 usb_fill_bulk_urb(urb, dev->udev, pipe,
 417                                   dev->vbi_mode.bulk_ctl.transfer_buffer[i],
 418                                   sb_size, cx231xx_irq_vbi_callback, dma_q);
 419         }
 420
 421         init_waitqueue_head(&dma_q->wq);
 422
 423         /* submit urbs and enables IRQ */
 424         for (i = 0; i < dev->vbi_mode.bulk_ctl.num_bufs; i++) {
 425                 rc = usb_submit_urb(dev->vbi_mode.bulk_ctl.urb[i], GFP_ATOMIC);
 426                 if (rc) {
 427                         dev_err(dev->dev,
 428                                 "submit of urb %i failed (error=%i)\n", i, rc);
 429                         cx231xx_uninit_vbi_isoc(dev);
 430                         return rc;
 431                 }
 432         }
 433
 434         cx231xx_capture_start(dev, 1, Vbi);
 435
 436         return 0;
 437 }
 438 EXPORT_SYMBOL_GPL(cx231xx_init_vbi_isoc);
 439
 440 u32 cx231xx_get_vbi_line(struct cx231xx *dev, struct cx231xx_dmaqueue *dma_q,
 441                          u8 sav_eav, u8 *p_buffer, u32 buffer_size)
 442 {
 443         u32 bytes_copied = 0;
 444         int current_field = -1;
 445
 446         switch (sav_eav) {
 447
 448         case SAV_VBI_FIELD1:
 449                 current_field = 1;
 450                 break;
 451
 452         case SAV_VBI_FIELD2:
 453                 current_field = 2;
 454                 break;
 455         default:
 456                 break;
 457         }
 458
 459         if (current_field < 0)
 460                 return bytes_copied;
 461
 462         dma_q->last_sav = sav_eav;
 463
 464         bytes_copied =
 465             cx231xx_copy_vbi_line(dev, dma_q, p_buffer, buffer_size,
 466                                   current_field);
 467
 468         return bytes_copied;
 469 }
 470
 471 /*
 472  * Announces that a buffer were filled and request the next
 473  */
 474 static inline void vbi_buffer_filled(struct cx231xx *dev,
 475                                      struct cx231xx_dmaqueue *dma_q,
 476                                      struct cx231xx_buffer *buf)
 477 {
 478         /* Advice that buffer was filled */
 479         /* dev_dbg(dev->dev, "[%p/%d] wakeup\n", buf, buf->vb.index); */
 480
 481         buf->vb.sequence = dma_q->sequence++;
 482         buf->vb.vb2_buf.timestamp = ktime_get_ns();
 483
 484         dev->vbi_mode.bulk_ctl.buf = NULL;
 485
 486         list_del(&buf->list);
 487         vb2_buffer_done(&buf->vb.vb2_buf, VB2_BUF_STATE_DONE);
 488 }
 489
 490 u32 cx231xx_copy_vbi_line(struct cx231xx *dev, struct cx231xx_dmaqueue *dma_q,
 491                           u8 *p_line, u32 length, int field_number)
 492 {
 493         u32 bytes_to_copy;
 494         struct cx231xx_buffer *buf;
 495         u32 _line_size = dev->width * 2;
 496
 497         if (dma_q->current_field == -1) {
 498                 /* Just starting up */
 499                 cx231xx_reset_vbi_buffer(dev, dma_q);
 500         }
 501
 502         if (dma_q->current_field != field_number)
 503                 dma_q->lines_completed = 0;
 504
 505         /* get the buffer pointer */
 506         buf = dev->vbi_mode.bulk_ctl.buf;
 507
 508         /* Remember the field number for next time */
 509         dma_q->current_field = field_number;
 510
 511         bytes_to_copy = dma_q->bytes_left_in_line;
 512         if (bytes_to_copy > length)
 513                 bytes_to_copy = length;
 514
 515         if (dma_q->lines_completed >= dma_q->lines_per_field) {
 516                 dma_q->bytes_left_in_line -= bytes_to_copy;
 517                 dma_q->is_partial_line =
 518                     (dma_q->bytes_left_in_line == 0) ? 0 : 1;
 519                 return 0;
 520         }
 521
 522         dma_q->is_partial_line = 1;
 523
 524         /* If we don't have a buffer, just return the number of bytes we would
 525            have copied if we had a buffer. */
 526         if (!buf) {
 527                 dma_q->bytes_left_in_line -= bytes_to_copy;
 528                 dma_q->is_partial_line =
 529                     (dma_q->bytes_left_in_line == 0) ? 0 : 1;
 530                 return bytes_to_copy;
 531         }
 532
 533         /* copy the data to video buffer */
 534         cx231xx_do_vbi_copy(dev, dma_q, p_line, bytes_to_copy);
 535
 536         dma_q->pos += bytes_to_copy;
 537         dma_q->bytes_left_in_line -= bytes_to_copy;
 538
 539         if (dma_q->bytes_left_in_line == 0) {
 540
 541                 dma_q->bytes_left_in_line = _line_size;
 542                 dma_q->lines_completed++;
 543                 dma_q->is_partial_line = 0;
 544
 545                 if (cx231xx_is_vbi_buffer_done(dev, dma_q) && buf) {
 546
 547                         vbi_buffer_filled(dev, dma_q, buf);
 548
 549                         dma_q->pos = 0;
 550                         dma_q->lines_completed = 0;
 551                         cx231xx_reset_vbi_buffer(dev, dma_q);
 552                 }
 553         }
 554
 555         return bytes_to_copy;
 556 }
 557
 558 /*
 559  * generic routine to get the next available buffer
 560  */
 561 static inline void get_next_vbi_buf(struct cx231xx_dmaqueue *dma_q,
 562                                     struct cx231xx_buffer **buf)
 563 {
 564         struct cx231xx_video_mode *vmode =
 565             container_of(dma_q, struct cx231xx_video_mode, vidq);
 566         struct cx231xx *dev = container_of(vmode, struct cx231xx, vbi_mode);
 567         char *outp;
 568
 569         if (list_empty(&dma_q->active)) {
 570                 dev_err(dev->dev, "No active queue to serve\n");
 571                 dev->vbi_mode.bulk_ctl.buf = NULL;
 572                 *buf = NULL;
 573                 return;
 574         }
 575
 576         /* Get the next buffer */
 577         *buf = list_entry(dma_q->active.next, struct cx231xx_buffer, list);
 578
 579         /* Cleans up buffer - Useful for testing for frame/URB loss */
 580         outp = vb2_plane_vaddr(&(*buf)->vb.vb2_buf, 0);
 581         memset(outp, 0, vb2_plane_size(&(*buf)->vb.vb2_buf, 0));
 582
 583         dev->vbi_mode.bulk_ctl.buf = *buf;
 584
 585         return;
 586 }
 587
 588 void cx231xx_reset_vbi_buffer(struct cx231xx *dev,
 589                               struct cx231xx_dmaqueue *dma_q)
 590 {
 591         struct cx231xx_buffer *buf;
 592
 593         buf = dev->vbi_mode.bulk_ctl.buf;
 594
 595         if (buf == NULL) {
 596                 /* first try to get the buffer */
 597                 get_next_vbi_buf(dma_q, &buf);
 598
 599                 dma_q->pos = 0;
 600                 dma_q->current_field = -1;
 601         }
 602
 603         dma_q->bytes_left_in_line = dev->width << 1;
 604         dma_q->lines_completed = 0;
 605 }
 606
 607 int cx231xx_do_vbi_copy(struct cx231xx *dev, struct cx231xx_dmaqueue *dma_q,
 608                         u8 *p_buffer, u32 bytes_to_copy)
 609 {
 610         u8 *p_out_buffer = NULL;
 611         u32 current_line_bytes_copied = 0;
 612         struct cx231xx_buffer *buf;
 613         u32 _line_size = dev->width << 1;
 614         void *startwrite;
 615         int offset, lencopy;
 616
 617         buf = dev->vbi_mode.bulk_ctl.buf;
 618
 619         if (buf == NULL)
 620                 return -EINVAL;
 621
 622         p_out_buffer = vb2_plane_vaddr(&buf->vb.vb2_buf, 0);
 623
 624         if (dma_q->bytes_left_in_line != _line_size) {
 625                 current_line_bytes_copied =
 626                     _line_size - dma_q->bytes_left_in_line;
 627         }
 628
 629         offset = (dma_q->lines_completed * _line_size) +
 630                  current_line_bytes_copied;
 631
 632         if (dma_q->current_field == 2) {
 633                 /* Populate the second half of the frame */
 634                 offset += (dev->width * 2 * dma_q->lines_per_field);
 635         }
 636
 637         /* prepare destination address */
 638         startwrite = p_out_buffer + offset;
 639
 640         lencopy = dma_q->bytes_left_in_line > bytes_to_copy ?
 641                   bytes_to_copy : dma_q->bytes_left_in_line;
 642
 643         memcpy(startwrite, p_buffer, lencopy);
 644
 645         return 0;
 646 }
 647
 648 u8 cx231xx_is_vbi_buffer_done(struct cx231xx *dev,
 649                               struct cx231xx_dmaqueue *dma_q)
 650 {
 651         u32 height = 0;
 652
 653         height = ((dev->norm & V4L2_STD_625_50) ?
 654                   PAL_VBI_LINES : NTSC_VBI_LINES);
 655         if (dma_q->lines_completed == height && dma_q->current_field == 2)
 656                 return 1;
 657         else
 658                 return 0;
 659 }