git.oblomov.eu Git - linux-2.6/blob - drivers/media/video/ivtv/ivtv-irq.c

   1 /* interrupt handling
   2     Copyright (C) 2003-2004  Kevin Thayer <nufan_wfk at yahoo.com>
   3     Copyright (C) 2004  Chris Kennedy <c@groovy.org>
   4     Copyright (C) 2005-2007  Hans Verkuil <hverkuil@xs4all.nl>
   5
   6     This program is free software; you can redistribute it and/or modify
   7     it under the terms of the GNU General Public License as published by
   8     the Free Software Foundation; either version 2 of the License, or
   9     (at your option) any later version.
  10
  11     This program is distributed in the hope that it will be useful,
  12     but WITHOUT ANY WARRANTY; without even the implied warranty of
  13     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14     GNU General Public License for more details.
  15
  16     You should have received a copy of the GNU General Public License
  17     along with this program; if not, write to the Free Software
  18     Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  19  */
  20
  21 #include "ivtv-driver.h"
  22 #include "ivtv-queue.h"
  23 #include "ivtv-udma.h"
  24 #include "ivtv-irq.h"
  25 #include "ivtv-mailbox.h"
  26 #include "ivtv-vbi.h"
  27 #include "ivtv-yuv.h"
  28
  29 #define DMA_MAGIC_COOKIE 0x000001fe
  30
  31 static void ivtv_dma_dec_start(struct ivtv_stream *s);
  32
  33 static const int ivtv_stream_map[] = {
  34         IVTV_ENC_STREAM_TYPE_MPG,
  35         IVTV_ENC_STREAM_TYPE_YUV,
  36         IVTV_ENC_STREAM_TYPE_PCM,
  37         IVTV_ENC_STREAM_TYPE_VBI,
  38 };
  39
  40
  41 static void ivtv_pio_work_handler(struct ivtv *itv)
  42 {
  43         struct ivtv_stream *s = &itv->streams[itv->cur_pio_stream];
  44         struct ivtv_buffer *buf;
  45         int i = 0;
  46
  47         IVTV_DEBUG_HI_DMA("ivtv_pio_work_handler\n");
  48         if (itv->cur_pio_stream < 0 || itv->cur_pio_stream >= IVTV_MAX_STREAMS ||
  49                         s->v4l2dev == NULL || !ivtv_use_pio(s)) {
  50                 itv->cur_pio_stream = -1;
  51                 /* trigger PIO complete user interrupt */
  52                 write_reg(IVTV_IRQ_ENC_PIO_COMPLETE, 0x44);
  53                 return;
  54         }
  55         IVTV_DEBUG_HI_DMA("Process PIO %s\n", s->name);
  56         list_for_each_entry(buf, &s->q_dma.list, list) {
  57                 u32 size = s->sg_processing[i].size & 0x3ffff;
  58
  59                 /* Copy the data from the card to the buffer */
  60                 if (s->type == IVTV_DEC_STREAM_TYPE_VBI) {
  61                         memcpy_fromio(buf->buf, itv->dec_mem + s->sg_processing[i].src - IVTV_DECODER_OFFSET, size);
  62                 }
  63                 else {
  64                         memcpy_fromio(buf->buf, itv->enc_mem + s->sg_processing[i].src, size);
  65                 }
  66                 i++;
  67                 if (i == s->sg_processing_size)
  68                         break;
  69         }
  70         write_reg(IVTV_IRQ_ENC_PIO_COMPLETE, 0x44);
  71 }
  72
  73 void ivtv_irq_work_handler(struct work_struct *work)
  74 {
  75         struct ivtv *itv = container_of(work, struct ivtv, irq_work_queue);
  76
  77         DEFINE_WAIT(wait);
  78
  79         if (test_and_clear_bit(IVTV_F_I_WORK_INITED, &itv->i_flags)) {
  80                 struct sched_param param = { .sched_priority = 99 };
  81
  82                 /* This thread must use the FIFO scheduler as it
  83                    is realtime sensitive. */
  84                 sched_setscheduler(current, SCHED_FIFO, &param);
  85         }
  86         if (test_and_clear_bit(IVTV_F_I_WORK_HANDLER_PIO, &itv->i_flags))
  87                 ivtv_pio_work_handler(itv);
  88
  89         if (test_and_clear_bit(IVTV_F_I_WORK_HANDLER_VBI, &itv->i_flags))
  90                 ivtv_vbi_work_handler(itv);
  91
  92         if (test_and_clear_bit(IVTV_F_I_WORK_HANDLER_YUV, &itv->i_flags))
  93                 ivtv_yuv_work_handler(itv);
  94 }
  95
  96 /* Determine the required DMA size, setup enough buffers in the predma queue and
  97    actually copy the data from the card to the buffers in case a PIO transfer is
  98    required for this stream.
  99  */
 100 static int stream_enc_dma_append(struct ivtv_stream *s, u32 data[CX2341X_MBOX_MAX_DATA])
 101 {
 102         struct ivtv *itv = s->itv;
 103         struct ivtv_buffer *buf;
 104         u32 bytes_needed = 0;
 105         u32 offset, size;
 106         u32 UVoffset = 0, UVsize = 0;
 107         int skip_bufs = s->q_predma.buffers;
 108         int idx = s->sg_pending_size;
 109         int rc;
 110
 111         /* sanity checks */
 112         if (s->v4l2dev == NULL) {
 113                 IVTV_DEBUG_WARN("Stream %s not started\n", s->name);
 114                 return -1;
 115         }
 116         if (!test_bit(IVTV_F_S_CLAIMED, &s->s_flags)) {
 117                 IVTV_DEBUG_WARN("Stream %s not open\n", s->name);
 118                 return -1;
 119         }
 120
 121         /* determine offset, size and PTS for the various streams */
 122         switch (s->type) {
 123                 case IVTV_ENC_STREAM_TYPE_MPG:
 124                         offset = data[1];
 125                         size = data[2];
 126                         s->pending_pts = 0;
 127                         break;
 128
 129                 case IVTV_ENC_STREAM_TYPE_YUV:
 130                         offset = data[1];
 131                         size = data[2];
 132                         UVoffset = data[3];
 133                         UVsize = data[4];
 134                         s->pending_pts = ((u64) data[5] << 32) | data[6];
 135                         break;
 136
 137                 case IVTV_ENC_STREAM_TYPE_PCM:
 138                         offset = data[1] + 12;
 139                         size = data[2] - 12;
 140                         s->pending_pts = read_dec(offset - 8) |
 141                                 ((u64)(read_dec(offset - 12)) << 32);
 142                         if (itv->has_cx23415)
 143                                 offset += IVTV_DECODER_OFFSET;
 144                         break;
 145
 146                 case IVTV_ENC_STREAM_TYPE_VBI:
 147                         size = itv->vbi.enc_size * itv->vbi.fpi;
 148                         offset = read_enc(itv->vbi.enc_start - 4) + 12;
 149                         if (offset == 12) {
 150                                 IVTV_DEBUG_INFO("VBI offset == 0\n");
 151                                 return -1;
 152                         }
 153                         s->pending_pts = read_enc(offset - 4) | ((u64)read_enc(offset - 8) << 32);
 154                         break;
 155
 156                 case IVTV_DEC_STREAM_TYPE_VBI:
 157                         size = read_dec(itv->vbi.dec_start + 4) + 8;
 158                         offset = read_dec(itv->vbi.dec_start) + itv->vbi.dec_start;
 159                         s->pending_pts = 0;
 160                         offset += IVTV_DECODER_OFFSET;
 161                         break;
 162                 default:
 163                         /* shouldn't happen */
 164                         return -1;
 165         }
 166
 167         /* if this is the start of the DMA then fill in the magic cookie */
 168         if (s->sg_pending_size == 0 && ivtv_use_dma(s)) {
 169                 if (itv->has_cx23415 && (s->type == IVTV_ENC_STREAM_TYPE_PCM ||
 170                     s->type == IVTV_DEC_STREAM_TYPE_VBI)) {
 171                         s->pending_backup = read_dec(offset - IVTV_DECODER_OFFSET);
 172                         write_dec_sync(cpu_to_le32(DMA_MAGIC_COOKIE), offset - IVTV_DECODER_OFFSET);
 173                 }
 174                 else {
 175                         s->pending_backup = read_enc(offset);
 176                         write_enc_sync(cpu_to_le32(DMA_MAGIC_COOKIE), offset);
 177                 }
 178                 s->pending_offset = offset;
 179         }
 180
 181         bytes_needed = size;
 182         if (s->type == IVTV_ENC_STREAM_TYPE_YUV) {
 183                 /* The size for the Y samples needs to be rounded upwards to a
 184                    multiple of the buf_size. The UV samples then start in the
 185                    next buffer. */
 186                 bytes_needed = s->buf_size * ((bytes_needed + s->buf_size - 1) / s->buf_size);
 187                 bytes_needed += UVsize;
 188         }
 189
 190         IVTV_DEBUG_HI_DMA("%s %s: 0x%08x bytes at 0x%08x\n",
 191                 ivtv_use_pio(s) ? "PIO" : "DMA", s->name, bytes_needed, offset);
 192
 193         rc = ivtv_queue_move(s, &s->q_free, &s->q_full, &s->q_predma, bytes_needed);
 194         if (rc < 0) { /* Insufficient buffers */
 195                 IVTV_DEBUG_WARN("Cannot obtain %d bytes for %s data transfer\n",
 196                                 bytes_needed, s->name);
 197                 return -1;
 198         }
 199         if (rc && !s->buffers_stolen && (s->s_flags & IVTV_F_S_APPL_IO)) {
 200                 IVTV_WARN("All %s stream buffers are full. Dropping data.\n", s->name);
 201                 IVTV_WARN("Cause: the application is not reading fast enough.\n");
 202         }
 203         s->buffers_stolen = rc;
 204
 205         /* got the buffers, now fill in sg_pending */
 206         buf = list_entry(s->q_predma.list.next, struct ivtv_buffer, list);
 207         memset(buf->buf, 0, 128);
 208         list_for_each_entry(buf, &s->q_predma.list, list) {
 209                 if (skip_bufs-- > 0)
 210                         continue;
 211                 s->sg_pending[idx].dst = buf->dma_handle;
 212                 s->sg_pending[idx].src = offset;
 213                 s->sg_pending[idx].size = s->buf_size;
 214                 buf->bytesused = min(size, s->buf_size);
 215                 buf->dma_xfer_cnt = s->dma_xfer_cnt;
 216
 217                 s->q_predma.bytesused += buf->bytesused;
 218                 size -= buf->bytesused;
 219                 offset += s->buf_size;
 220
 221                 /* Sync SG buffers */
 222                 ivtv_buf_sync_for_device(s, buf);
 223
 224                 if (size == 0) {        /* YUV */
 225                         /* process the UV section */
 226                         offset = UVoffset;
 227                         size = UVsize;
 228                 }
 229                 idx++;
 230         }
 231         s->sg_pending_size = idx;
 232         return 0;
 233 }
 234
 235 static void dma_post(struct ivtv_stream *s)
 236 {
 237         struct ivtv *itv = s->itv;
 238         struct ivtv_buffer *buf = NULL;
 239         struct list_head *p;
 240         u32 offset;
 241         __le32 *u32buf;
 242         int x = 0;
 243
 244         IVTV_DEBUG_HI_DMA("%s %s completed (%x)\n", ivtv_use_pio(s) ? "PIO" : "DMA",
 245                         s->name, s->dma_offset);
 246         list_for_each(p, &s->q_dma.list) {
 247                 buf = list_entry(p, struct ivtv_buffer, list);
 248                 u32buf = (__le32 *)buf->buf;
 249
 250                 /* Sync Buffer */
 251                 ivtv_buf_sync_for_cpu(s, buf);
 252
 253                 if (x == 0 && ivtv_use_dma(s)) {
 254                         offset = s->dma_last_offset;
 255                         if (u32buf[offset / 4] != DMA_MAGIC_COOKIE)
 256                         {
 257                                 for (offset = 0; offset < 64; offset++) {
 258                                         if (u32buf[offset] == DMA_MAGIC_COOKIE) {
 259                                                 break;
 260                                         }
 261                                 }
 262                                 offset *= 4;
 263                                 if (offset == 256) {
 264                                         IVTV_DEBUG_WARN("%s: Couldn't find start of buffer within the first 256 bytes\n", s->name);
 265                                         offset = s->dma_last_offset;
 266                                 }
 267                                 if (s->dma_last_offset != offset)
 268                                         IVTV_DEBUG_WARN("%s: offset %d -> %d\n", s->name, s->dma_last_offset, offset);
 269                                 s->dma_last_offset = offset;
 270                         }
 271                         if (itv->has_cx23415 && (s->type == IVTV_ENC_STREAM_TYPE_PCM ||
 272                                                 s->type == IVTV_DEC_STREAM_TYPE_VBI)) {
 273                                 write_dec_sync(0, s->dma_offset - IVTV_DECODER_OFFSET);
 274                         }
 275                         else {
 276                                 write_enc_sync(0, s->dma_offset);
 277                         }
 278                         if (offset) {
 279                                 buf->bytesused -= offset;
 280                                 memcpy(buf->buf, buf->buf + offset, buf->bytesused + offset);
 281                         }
 282                         *u32buf = cpu_to_le32(s->dma_backup);
 283                 }
 284                 x++;
 285                 /* flag byteswap ABCD -> DCBA for MPG & VBI data outside irq */
 286                 if (s->type == IVTV_ENC_STREAM_TYPE_MPG ||
 287                     s->type == IVTV_ENC_STREAM_TYPE_VBI)
 288                         buf->b_flags |= IVTV_F_B_NEED_BUF_SWAP;
 289         }
 290         if (buf)
 291                 buf->bytesused += s->dma_last_offset;
 292         if (buf && s->type == IVTV_DEC_STREAM_TYPE_VBI) {
 293                 list_for_each_entry(buf, &s->q_dma.list, list) {
 294                         /* Parse and Groom VBI Data */
 295                         s->q_dma.bytesused -= buf->bytesused;
 296                         ivtv_process_vbi_data(itv, buf, 0, s->type);
 297                         s->q_dma.bytesused += buf->bytesused;
 298                 }
 299                 if (s->id == -1) {
 300                         ivtv_queue_move(s, &s->q_dma, NULL, &s->q_free, 0);
 301                         return;
 302                 }
 303         }
 304         ivtv_queue_move(s, &s->q_dma, NULL, &s->q_full, s->q_dma.bytesused);
 305         if (s->id != -1)
 306                 wake_up(&s->waitq);
 307 }
 308
 309 void ivtv_dma_stream_dec_prepare(struct ivtv_stream *s, u32 offset, int lock)
 310 {
 311         struct ivtv *itv = s->itv;
 312         struct yuv_playback_info *yi = &itv->yuv_info;
 313         u8 frame = yi->draw_frame;
 314         struct yuv_frame_info *f = &yi->new_frame_info[frame];
 315         struct ivtv_buffer *buf;
 316         u32 y_size = 720 * ((f->src_h + 31) & ~31);
 317         u32 uv_offset = offset + IVTV_YUV_BUFFER_UV_OFFSET;
 318         int y_done = 0;
 319         int bytes_written = 0;
 320         unsigned long flags = 0;
 321         int idx = 0;
 322
 323         IVTV_DEBUG_HI_DMA("DEC PREPARE DMA %s: %08x %08x\n", s->name, s->q_predma.bytesused, offset);
 324
 325         /* Insert buffer block for YUV if needed */
 326         if (s->type == IVTV_DEC_STREAM_TYPE_YUV && f->offset_y) {
 327                 if (yi->blanking_dmaptr) {
 328                         s->sg_pending[idx].src = yi->blanking_dmaptr;
 329                         s->sg_pending[idx].dst = offset;
 330                         s->sg_pending[idx].size = 720 * 16;
 331                 }
 332                 offset += 720 * 16;
 333                 idx++;
 334         }
 335
 336         list_for_each_entry(buf, &s->q_predma.list, list) {
 337                 /* YUV UV Offset from Y Buffer */
 338                 if (s->type == IVTV_DEC_STREAM_TYPE_YUV && !y_done &&
 339                                 (bytes_written + buf->bytesused) >= y_size) {
 340                         s->sg_pending[idx].src = buf->dma_handle;
 341                         s->sg_pending[idx].dst = offset;
 342                         s->sg_pending[idx].size = y_size - bytes_written;
 343                         offset = uv_offset;
 344                         if (s->sg_pending[idx].size != buf->bytesused) {
 345                                 idx++;
 346                                 s->sg_pending[idx].src =
 347                                   buf->dma_handle + s->sg_pending[idx - 1].size;
 348                                 s->sg_pending[idx].dst = offset;
 349                                 s->sg_pending[idx].size =
 350                                    buf->bytesused - s->sg_pending[idx - 1].size;
 351                                 offset += s->sg_pending[idx].size;
 352                         }
 353                         y_done = 1;
 354                 } else {
 355                         s->sg_pending[idx].src = buf->dma_handle;
 356                         s->sg_pending[idx].dst = offset;
 357                         s->sg_pending[idx].size = buf->bytesused;
 358                         offset += buf->bytesused;
 359                 }
 360                 bytes_written += buf->bytesused;
 361
 362                 /* Sync SG buffers */
 363                 ivtv_buf_sync_for_device(s, buf);
 364                 idx++;
 365         }
 366         s->sg_pending_size = idx;
 367
 368         /* Sync Hardware SG List of buffers */
 369         ivtv_stream_sync_for_device(s);
 370         if (lock)
 371                 spin_lock_irqsave(&itv->dma_reg_lock, flags);
 372         if (!test_bit(IVTV_F_I_DMA, &itv->i_flags)) {
 373                 ivtv_dma_dec_start(s);
 374         }
 375         else {
 376                 set_bit(IVTV_F_S_DMA_PENDING, &s->s_flags);
 377         }
 378         if (lock)
 379                 spin_unlock_irqrestore(&itv->dma_reg_lock, flags);
 380 }
 381
 382 static void ivtv_dma_enc_start_xfer(struct ivtv_stream *s)
 383 {
 384         struct ivtv *itv = s->itv;
 385
 386         s->sg_dma->src = cpu_to_le32(s->sg_processing[s->sg_processed].src);
 387         s->sg_dma->dst = cpu_to_le32(s->sg_processing[s->sg_processed].dst);
 388         s->sg_dma->size = cpu_to_le32(s->sg_processing[s->sg_processed].size | 0x80000000);
 389         s->sg_processed++;
 390         /* Sync Hardware SG List of buffers */
 391         ivtv_stream_sync_for_device(s);
 392         write_reg(s->sg_handle, IVTV_REG_ENCDMAADDR);
 393         write_reg_sync(read_reg(IVTV_REG_DMAXFER) | 0x02, IVTV_REG_DMAXFER);
 394         itv->dma_timer.expires = jiffies + msecs_to_jiffies(300);
 395         add_timer(&itv->dma_timer);
 396 }
 397
 398 static void ivtv_dma_dec_start_xfer(struct ivtv_stream *s)
 399 {
 400         struct ivtv *itv = s->itv;
 401
 402         s->sg_dma->src = cpu_to_le32(s->sg_processing[s->sg_processed].src);
 403         s->sg_dma->dst = cpu_to_le32(s->sg_processing[s->sg_processed].dst);
 404         s->sg_dma->size = cpu_to_le32(s->sg_processing[s->sg_processed].size | 0x80000000);
 405         s->sg_processed++;
 406         /* Sync Hardware SG List of buffers */
 407         ivtv_stream_sync_for_device(s);
 408         write_reg(s->sg_handle, IVTV_REG_DECDMAADDR);
 409         write_reg_sync(read_reg(IVTV_REG_DMAXFER) | 0x01, IVTV_REG_DMAXFER);
 410         itv->dma_timer.expires = jiffies + msecs_to_jiffies(300);
 411         add_timer(&itv->dma_timer);
 412 }
 413
 414 /* start the encoder DMA */
 415 static void ivtv_dma_enc_start(struct ivtv_stream *s)
 416 {
 417         struct ivtv *itv = s->itv;
 418         struct ivtv_stream *s_vbi = &itv->streams[IVTV_ENC_STREAM_TYPE_VBI];
 419         int i;
 420
 421         IVTV_DEBUG_HI_DMA("start %s for %s\n", ivtv_use_dma(s) ? "DMA" : "PIO", s->name);
 422
 423         if (s->q_predma.bytesused)
 424                 ivtv_queue_move(s, &s->q_predma, NULL, &s->q_dma, s->q_predma.bytesused);
 425
 426         if (ivtv_use_dma(s))
 427                 s->sg_pending[s->sg_pending_size - 1].size += 256;
 428
 429         /* If this is an MPEG stream, and VBI data is also pending, then append the
 430            VBI DMA to the MPEG DMA and transfer both sets of data at once.
 431
 432            VBI DMA is a second class citizen compared to MPEG and mixing them together
 433            will confuse the firmware (the end of a VBI DMA is seen as the end of a
 434            MPEG DMA, thus effectively dropping an MPEG frame). So instead we make
 435            sure we only use the MPEG DMA to transfer the VBI DMA if both are in
 436            use. This way no conflicts occur. */
 437         clear_bit(IVTV_F_S_DMA_HAS_VBI, &s->s_flags);
 438         if (s->type == IVTV_ENC_STREAM_TYPE_MPG && s_vbi->sg_pending_size &&
 439                         s->sg_pending_size + s_vbi->sg_pending_size <= s->buffers) {
 440                 ivtv_queue_move(s_vbi, &s_vbi->q_predma, NULL, &s_vbi->q_dma, s_vbi->q_predma.bytesused);
 441                 if (ivtv_use_dma(s_vbi))
 442                         s_vbi->sg_pending[s_vbi->sg_pending_size - 1].size += 256;
 443                 for (i = 0; i < s_vbi->sg_pending_size; i++) {
 444                         s->sg_pending[s->sg_pending_size++] = s_vbi->sg_pending[i];
 445                 }
 446                 s_vbi->dma_offset = s_vbi->pending_offset;
 447                 s_vbi->sg_pending_size = 0;
 448                 s_vbi->dma_xfer_cnt++;
 449                 set_bit(IVTV_F_S_DMA_HAS_VBI, &s->s_flags);
 450                 IVTV_DEBUG_HI_DMA("include DMA for %s\n", s_vbi->name);
 451         }
 452
 453         s->dma_xfer_cnt++;
 454         memcpy(s->sg_processing, s->sg_pending, sizeof(struct ivtv_sg_host_element) * s->sg_pending_size);
 455         s->sg_processing_size = s->sg_pending_size;
 456         s->sg_pending_size = 0;
 457         s->sg_processed = 0;
 458         s->dma_offset = s->pending_offset;
 459         s->dma_backup = s->pending_backup;
 460         s->dma_pts = s->pending_pts;
 461
 462         if (ivtv_use_pio(s)) {
 463                 set_bit(IVTV_F_I_WORK_HANDLER_PIO, &itv->i_flags);
 464                 set_bit(IVTV_F_I_HAVE_WORK, &itv->i_flags);
 465                 set_bit(IVTV_F_I_PIO, &itv->i_flags);
 466                 itv->cur_pio_stream = s->type;
 467         }
 468         else {
 469                 itv->dma_retries = 0;
 470                 ivtv_dma_enc_start_xfer(s);
 471                 set_bit(IVTV_F_I_DMA, &itv->i_flags);
 472                 itv->cur_dma_stream = s->type;
 473         }
 474 }
 475
 476 static void ivtv_dma_dec_start(struct ivtv_stream *s)
 477 {
 478         struct ivtv *itv = s->itv;
 479
 480         if (s->q_predma.bytesused)
 481                 ivtv_queue_move(s, &s->q_predma, NULL, &s->q_dma, s->q_predma.bytesused);
 482         s->dma_xfer_cnt++;
 483         memcpy(s->sg_processing, s->sg_pending, sizeof(struct ivtv_sg_host_element) * s->sg_pending_size);
 484         s->sg_processing_size = s->sg_pending_size;
 485         s->sg_pending_size = 0;
 486         s->sg_processed = 0;
 487
 488         IVTV_DEBUG_HI_DMA("start DMA for %s\n", s->name);
 489         itv->dma_retries = 0;
 490         ivtv_dma_dec_start_xfer(s);
 491         set_bit(IVTV_F_I_DMA, &itv->i_flags);
 492         itv->cur_dma_stream = s->type;
 493 }
 494
 495 static void ivtv_irq_dma_read(struct ivtv *itv)
 496 {
 497         struct ivtv_stream *s = NULL;
 498         struct ivtv_buffer *buf;
 499         int hw_stream_type = 0;
 500
 501         IVTV_DEBUG_HI_IRQ("DEC DMA READ\n");
 502
 503         del_timer(&itv->dma_timer);
 504
 505         if (!test_bit(IVTV_F_I_UDMA, &itv->i_flags) && itv->cur_dma_stream < 0)
 506                 return;
 507
 508         if (!test_bit(IVTV_F_I_UDMA, &itv->i_flags)) {
 509                 s = &itv->streams[itv->cur_dma_stream];
 510                 ivtv_stream_sync_for_cpu(s);
 511
 512                 if (read_reg(IVTV_REG_DMASTATUS) & 0x14) {
 513                         IVTV_DEBUG_WARN("DEC DMA ERROR %x (xfer %d of %d, retry %d)\n",
 514                                         read_reg(IVTV_REG_DMASTATUS),
 515                                         s->sg_processed, s->sg_processing_size, itv->dma_retries);
 516                         write_reg(read_reg(IVTV_REG_DMASTATUS) & 3, IVTV_REG_DMASTATUS);
 517                         if (itv->dma_retries == 3) {
 518                                 /* Too many retries, give up on this frame */
 519                                 itv->dma_retries = 0;
 520                                 s->sg_processed = s->sg_processing_size;
 521                         }
 522                         else {
 523                                 /* Retry, starting with the first xfer segment.
 524                                    Just retrying the current segment is not sufficient. */
 525                                 s->sg_processed = 0;
 526                                 itv->dma_retries++;
 527                         }
 528                 }
 529                 if (s->sg_processed < s->sg_processing_size) {
 530                         /* DMA next buffer */
 531                         ivtv_dma_dec_start_xfer(s);
 532                         return;
 533                 }
 534                 if (s->type == IVTV_DEC_STREAM_TYPE_YUV)
 535                         hw_stream_type = 2;
 536                 IVTV_DEBUG_HI_DMA("DEC DATA READ %s: %d\n", s->name, s->q_dma.bytesused);
 537
 538                 /* For some reason must kick the firmware, like PIO mode,
 539                    I think this tells the firmware we are done and the size
 540                    of the xfer so it can calculate what we need next.
 541                    I think we can do this part ourselves but would have to
 542                    fully calculate xfer info ourselves and not use interrupts
 543                  */
 544                 ivtv_vapi(itv, CX2341X_DEC_SCHED_DMA_FROM_HOST, 3, 0, s->q_dma.bytesused,
 545                                 hw_stream_type);
 546
 547                 /* Free last DMA call */
 548                 while ((buf = ivtv_dequeue(s, &s->q_dma)) != NULL) {
 549                         ivtv_buf_sync_for_cpu(s, buf);
 550                         ivtv_enqueue(s, buf, &s->q_free);
 551                 }
 552                 wake_up(&s->waitq);
 553         }
 554         clear_bit(IVTV_F_I_UDMA, &itv->i_flags);
 555         clear_bit(IVTV_F_I_DMA, &itv->i_flags);
 556         itv->cur_dma_stream = -1;
 557         wake_up(&itv->dma_waitq);
 558 }
 559
 560 static void ivtv_irq_enc_dma_complete(struct ivtv *itv)
 561 {
 562         u32 data[CX2341X_MBOX_MAX_DATA];
 563         struct ivtv_stream *s;
 564
 565         ivtv_api_get_data(&itv->enc_mbox, IVTV_MBOX_DMA_END, data);
 566         IVTV_DEBUG_HI_IRQ("ENC DMA COMPLETE %x %d (%d)\n", data[0], data[1], itv->cur_dma_stream);
 567
 568         del_timer(&itv->dma_timer);
 569
 570         if (itv->cur_dma_stream < 0)
 571                 return;
 572
 573         s = &itv->streams[itv->cur_dma_stream];
 574         ivtv_stream_sync_for_cpu(s);
 575
 576         if (data[0] & 0x18) {
 577                 IVTV_DEBUG_WARN("ENC DMA ERROR %x (offset %08x, xfer %d of %d, retry %d)\n", data[0],
 578                         s->dma_offset, s->sg_processed, s->sg_processing_size, itv->dma_retries);
 579                 write_reg(read_reg(IVTV_REG_DMASTATUS) & 3, IVTV_REG_DMASTATUS);
 580                 if (itv->dma_retries == 3) {
 581                         /* Too many retries, give up on this frame */
 582                         itv->dma_retries = 0;
 583                         s->sg_processed = s->sg_processing_size;
 584                 }
 585                 else {
 586                         /* Retry, starting with the first xfer segment.
 587                            Just retrying the current segment is not sufficient. */
 588                         s->sg_processed = 0;
 589                         itv->dma_retries++;
 590                 }
 591         }
 592         if (s->sg_processed < s->sg_processing_size) {
 593                 /* DMA next buffer */
 594                 ivtv_dma_enc_start_xfer(s);
 595                 return;
 596         }
 597         clear_bit(IVTV_F_I_DMA, &itv->i_flags);
 598         itv->cur_dma_stream = -1;
 599         dma_post(s);
 600         if (test_and_clear_bit(IVTV_F_S_DMA_HAS_VBI, &s->s_flags)) {
 601                 s = &itv->streams[IVTV_ENC_STREAM_TYPE_VBI];
 602                 dma_post(s);
 603         }
 604         s->sg_processing_size = 0;
 605         s->sg_processed = 0;
 606         wake_up(&itv->dma_waitq);
 607 }
 608
 609 static void ivtv_irq_enc_pio_complete(struct ivtv *itv)
 610 {
 611         struct ivtv_stream *s;
 612
 613         if (itv->cur_pio_stream < 0 || itv->cur_pio_stream >= IVTV_MAX_STREAMS) {
 614                 itv->cur_pio_stream = -1;
 615                 return;
 616         }
 617         s = &itv->streams[itv->cur_pio_stream];
 618         IVTV_DEBUG_HI_IRQ("ENC PIO COMPLETE %s\n", s->name);
 619         clear_bit(IVTV_F_I_PIO, &itv->i_flags);
 620         itv->cur_pio_stream = -1;
 621         dma_post(s);
 622         if (s->type == IVTV_ENC_STREAM_TYPE_MPG)
 623                 ivtv_vapi(itv, CX2341X_ENC_SCHED_DMA_TO_HOST, 3, 0, 0, 0);
 624         else if (s->type == IVTV_ENC_STREAM_TYPE_YUV)
 625                 ivtv_vapi(itv, CX2341X_ENC_SCHED_DMA_TO_HOST, 3, 0, 0, 1);
 626         else if (s->type == IVTV_ENC_STREAM_TYPE_PCM)
 627                 ivtv_vapi(itv, CX2341X_ENC_SCHED_DMA_TO_HOST, 3, 0, 0, 2);
 628         clear_bit(IVTV_F_I_PIO, &itv->i_flags);
 629         if (test_and_clear_bit(IVTV_F_S_DMA_HAS_VBI, &s->s_flags)) {
 630                 s = &itv->streams[IVTV_ENC_STREAM_TYPE_VBI];
 631                 dma_post(s);
 632         }
 633         wake_up(&itv->dma_waitq);
 634 }
 635
 636 static void ivtv_irq_dma_err(struct ivtv *itv)
 637 {
 638         u32 data[CX2341X_MBOX_MAX_DATA];
 639
 640         del_timer(&itv->dma_timer);
 641         ivtv_api_get_data(&itv->enc_mbox, IVTV_MBOX_DMA_END, data);
 642         IVTV_DEBUG_WARN("DMA ERROR %08x %08x %08x %d\n", data[0], data[1],
 643                                 read_reg(IVTV_REG_DMASTATUS), itv->cur_dma_stream);
 644         write_reg(read_reg(IVTV_REG_DMASTATUS) & 3, IVTV_REG_DMASTATUS);
 645         if (!test_bit(IVTV_F_I_UDMA, &itv->i_flags) &&
 646             itv->cur_dma_stream >= 0 && itv->cur_dma_stream < IVTV_MAX_STREAMS) {
 647                 struct ivtv_stream *s = &itv->streams[itv->cur_dma_stream];
 648
 649                 /* retry */
 650                 if (s->type >= IVTV_DEC_STREAM_TYPE_MPG)
 651                         ivtv_dma_dec_start(s);
 652                 else
 653                         ivtv_dma_enc_start(s);
 654                 return;
 655         }
 656         if (test_bit(IVTV_F_I_UDMA, &itv->i_flags)) {
 657                 ivtv_udma_start(itv);
 658                 return;
 659         }
 660         clear_bit(IVTV_F_I_UDMA, &itv->i_flags);
 661         clear_bit(IVTV_F_I_DMA, &itv->i_flags);
 662         itv->cur_dma_stream = -1;
 663         wake_up(&itv->dma_waitq);
 664 }
 665
 666 static void ivtv_irq_enc_start_cap(struct ivtv *itv)
 667 {
 668         u32 data[CX2341X_MBOX_MAX_DATA];
 669         struct ivtv_stream *s;
 670
 671         /* Get DMA destination and size arguments from card */
 672         ivtv_api_get_data(&itv->enc_mbox, IVTV_MBOX_DMA, data);
 673         IVTV_DEBUG_HI_IRQ("ENC START CAP %d: %08x %08x\n", data[0], data[1], data[2]);
 674
 675         if (data[0] > 2 || data[1] == 0 || data[2] == 0) {
 676                 IVTV_DEBUG_WARN("Unknown input: %08x %08x %08x\n",
 677                                 data[0], data[1], data[2]);
 678                 return;
 679         }
 680         s = &itv->streams[ivtv_stream_map[data[0]]];
 681         if (!stream_enc_dma_append(s, data)) {
 682                 set_bit(ivtv_use_pio(s) ? IVTV_F_S_PIO_PENDING : IVTV_F_S_DMA_PENDING, &s->s_flags);
 683         }
 684 }
 685
 686 static void ivtv_irq_enc_vbi_cap(struct ivtv *itv)
 687 {
 688         u32 data[CX2341X_MBOX_MAX_DATA];
 689         struct ivtv_stream *s;
 690
 691         IVTV_DEBUG_HI_IRQ("ENC START VBI CAP\n");
 692         s = &itv->streams[IVTV_ENC_STREAM_TYPE_VBI];
 693
 694         if (!stream_enc_dma_append(s, data))
 695                 set_bit(ivtv_use_pio(s) ? IVTV_F_S_PIO_PENDING : IVTV_F_S_DMA_PENDING, &s->s_flags);
 696 }
 697
 698 static void ivtv_irq_dec_vbi_reinsert(struct ivtv *itv)
 699 {
 700         u32 data[CX2341X_MBOX_MAX_DATA];
 701         struct ivtv_stream *s = &itv->streams[IVTV_DEC_STREAM_TYPE_VBI];
 702
 703         IVTV_DEBUG_HI_IRQ("DEC VBI REINSERT\n");
 704         if (test_bit(IVTV_F_S_CLAIMED, &s->s_flags) &&
 705                         !stream_enc_dma_append(s, data)) {
 706                 set_bit(IVTV_F_S_PIO_PENDING, &s->s_flags);
 707         }
 708 }
 709
 710 static void ivtv_irq_dec_data_req(struct ivtv *itv)
 711 {
 712         u32 data[CX2341X_MBOX_MAX_DATA];
 713         struct ivtv_stream *s;
 714
 715         /* YUV or MPG */
 716         ivtv_api_get_data(&itv->dec_mbox, IVTV_MBOX_DMA, data);
 717
 718         if (test_bit(IVTV_F_I_DEC_YUV, &itv->i_flags)) {
 719                 itv->dma_data_req_size =
 720                                  1080 * ((itv->yuv_info.v4l2_src_h + 31) & ~31);
 721                 itv->dma_data_req_offset = data[1];
 722                 if (atomic_read(&itv->yuv_info.next_dma_frame) >= 0)
 723                         ivtv_yuv_frame_complete(itv);
 724                 s = &itv->streams[IVTV_DEC_STREAM_TYPE_YUV];
 725         }
 726         else {
 727                 itv->dma_data_req_size = min_t(u32, data[2], 0x10000);
 728                 itv->dma_data_req_offset = data[1];
 729                 s = &itv->streams[IVTV_DEC_STREAM_TYPE_MPG];
 730         }
 731         IVTV_DEBUG_HI_IRQ("DEC DATA REQ %s: %d %08x %u\n", s->name, s->q_full.bytesused,
 732                        itv->dma_data_req_offset, itv->dma_data_req_size);
 733         if (itv->dma_data_req_size == 0 || s->q_full.bytesused < itv->dma_data_req_size) {
 734                 set_bit(IVTV_F_S_NEEDS_DATA, &s->s_flags);
 735         }
 736         else {
 737                 if (test_bit(IVTV_F_I_DEC_YUV, &itv->i_flags))
 738                         ivtv_yuv_setup_stream_frame(itv);
 739                 clear_bit(IVTV_F_S_NEEDS_DATA, &s->s_flags);
 740                 ivtv_queue_move(s, &s->q_full, NULL, &s->q_predma, itv->dma_data_req_size);
 741                 ivtv_dma_stream_dec_prepare(s, itv->dma_data_req_offset + IVTV_DECODER_OFFSET, 0);
 742         }
 743 }
 744
 745 static void ivtv_irq_vsync(struct ivtv *itv)
 746 {
 747         /* The vsync interrupt is unusual in that it won't clear until
 748          * the end of the first line for the current field, at which
 749          * point it clears itself. This can result in repeated vsync
 750          * interrupts, or a missed vsync. Read some of the registers
 751          * to determine the line being displayed and ensure we handle
 752          * one vsync per frame.
 753          */
 754         unsigned int frame = read_reg(0x28c0) & 1;
 755         struct yuv_playback_info *yi = &itv->yuv_info;
 756         int last_dma_frame = atomic_read(&itv->yuv_info.next_dma_frame);
 757         struct yuv_frame_info *f = &yi->new_frame_info[last_dma_frame];
 758
 759         if (0) IVTV_DEBUG_IRQ("DEC VSYNC\n");
 760
 761         if (((frame ^ f->sync_field) == 0 &&
 762                 ((itv->last_vsync_field & 1) ^ f->sync_field)) ||
 763                         (frame != (itv->last_vsync_field & 1) && !f->interlaced)) {
 764                 int next_dma_frame = last_dma_frame;
 765
 766                 if (!(f->interlaced && f->delay && yi->fields_lapsed < 1)) {
 767                         if (next_dma_frame >= 0 && next_dma_frame != atomic_read(&yi->next_fill_frame)) {
 768                                 write_reg(yuv_offset[next_dma_frame] >> 4, 0x82c);
 769                                 write_reg((yuv_offset[next_dma_frame] + IVTV_YUV_BUFFER_UV_OFFSET) >> 4, 0x830);
 770                                 write_reg(yuv_offset[next_dma_frame] >> 4, 0x834);
 771                                 write_reg((yuv_offset[next_dma_frame] + IVTV_YUV_BUFFER_UV_OFFSET) >> 4, 0x838);
 772                                 next_dma_frame = (next_dma_frame + 1) % IVTV_YUV_BUFFERS;
 773                                 atomic_set(&yi->next_dma_frame, next_dma_frame);
 774                                 yi->fields_lapsed = -1;
 775                         }
 776                 }
 777         }
 778         if (frame != (itv->last_vsync_field & 1)) {
 779                 struct ivtv_stream *s = ivtv_get_output_stream(itv);
 780
 781                 itv->last_vsync_field += 1;
 782                 if (frame == 0) {
 783                         clear_bit(IVTV_F_I_VALID_DEC_TIMINGS, &itv->i_flags);
 784                         clear_bit(IVTV_F_I_EV_VSYNC_FIELD, &itv->i_flags);
 785                 }
 786                 else {
 787                         set_bit(IVTV_F_I_EV_VSYNC_FIELD, &itv->i_flags);
 788                 }
 789                 if (test_bit(IVTV_F_I_EV_VSYNC_ENABLED, &itv->i_flags)) {
 790                         set_bit(IVTV_F_I_EV_VSYNC, &itv->i_flags);
 791                         wake_up(&itv->event_waitq);
 792                 }
 793                 wake_up(&itv->vsync_waitq);
 794                 if (s)
 795                         wake_up(&s->waitq);
 796
 797                 /* Send VBI to saa7127 */
 798                 if (frame && (itv->output_mode == OUT_PASSTHROUGH ||
 799                         test_bit(IVTV_F_I_UPDATE_WSS, &itv->i_flags) ||
 800                         test_bit(IVTV_F_I_UPDATE_VPS, &itv->i_flags) ||
 801                         test_bit(IVTV_F_I_UPDATE_CC, &itv->i_flags))) {
 802                         set_bit(IVTV_F_I_WORK_HANDLER_VBI, &itv->i_flags);
 803                         set_bit(IVTV_F_I_HAVE_WORK, &itv->i_flags);
 804                 }
 805
 806                 /* Check if we need to update the yuv registers */
 807                 if ((yi->yuv_forced_update || f->update) && last_dma_frame != -1) {
 808                         if (!f->update) {
 809                                 last_dma_frame = (u8)(last_dma_frame - 1) % IVTV_YUV_BUFFERS;
 810                                 f = &yi->new_frame_info[last_dma_frame];
 811                         }
 812
 813                         if (f->src_w) {
 814                                 yi->update_frame = last_dma_frame;
 815                                 f->update = 0;
 816                                 yi->yuv_forced_update = 0;
 817                                 set_bit(IVTV_F_I_WORK_HANDLER_YUV, &itv->i_flags);
 818                                 set_bit(IVTV_F_I_HAVE_WORK, &itv->i_flags);
 819                         }
 820                 }
 821
 822                 yi->fields_lapsed++;
 823         }
 824 }
 825
 826 #define IVTV_IRQ_DMA (IVTV_IRQ_DMA_READ | IVTV_IRQ_ENC_DMA_COMPLETE | IVTV_IRQ_DMA_ERR | IVTV_IRQ_ENC_START_CAP | IVTV_IRQ_ENC_VBI_CAP | IVTV_IRQ_DEC_DATA_REQ | IVTV_IRQ_DEC_VBI_RE_INSERT)
 827
 828 irqreturn_t ivtv_irq_handler(int irq, void *dev_id)
 829 {
 830         struct ivtv *itv = (struct ivtv *)dev_id;
 831         u32 combo;
 832         u32 stat;
 833         int i;
 834         u8 vsync_force = 0;
 835
 836         spin_lock(&itv->dma_reg_lock);
 837         /* get contents of irq status register */
 838         stat = read_reg(IVTV_REG_IRQSTATUS);
 839
 840         combo = ~itv->irqmask & stat;
 841
 842         /* Clear out IRQ */
 843         if (combo) write_reg(combo, IVTV_REG_IRQSTATUS);
 844
 845         if (0 == combo) {
 846                 /* The vsync interrupt is unusual and clears itself. If we
 847                  * took too long, we may have missed it. Do some checks
 848                  */
 849                 if (~itv->irqmask & IVTV_IRQ_DEC_VSYNC) {
 850                         /* vsync is enabled, see if we're in a new field */
 851                         if ((itv->last_vsync_field & 1) != (read_reg(0x28c0) & 1)) {
 852                                 /* New field, looks like we missed it */
 853                                 IVTV_DEBUG_YUV("VSync interrupt missed %d\n",read_reg(0x28c0)>>16);
 854                                 vsync_force = 1;
 855                         }
 856                 }
 857
 858                 if (!vsync_force) {
 859                         /* No Vsync expected, wasn't for us */
 860                         spin_unlock(&itv->dma_reg_lock);
 861                         return IRQ_NONE;
 862                 }
 863         }
 864
 865         /* Exclude interrupts noted below from the output, otherwise the log is flooded with
 866            these messages */
 867         if (combo & ~0xff6d0400)
 868                 IVTV_DEBUG_HI_IRQ("======= valid IRQ bits: 0x%08x ======\n", combo);
 869
 870         if (combo & IVTV_IRQ_DEC_DMA_COMPLETE) {
 871                 IVTV_DEBUG_HI_IRQ("DEC DMA COMPLETE\n");
 872         }
 873
 874         if (combo & IVTV_IRQ_DMA_READ) {
 875                 ivtv_irq_dma_read(itv);
 876         }
 877
 878         if (combo & IVTV_IRQ_ENC_DMA_COMPLETE) {
 879                 ivtv_irq_enc_dma_complete(itv);
 880         }
 881
 882         if (combo & IVTV_IRQ_ENC_PIO_COMPLETE) {
 883                 ivtv_irq_enc_pio_complete(itv);
 884         }
 885
 886         if (combo & IVTV_IRQ_DMA_ERR) {
 887                 ivtv_irq_dma_err(itv);
 888         }
 889
 890         if (combo & IVTV_IRQ_ENC_START_CAP) {
 891                 ivtv_irq_enc_start_cap(itv);
 892         }
 893
 894         if (combo & IVTV_IRQ_ENC_VBI_CAP) {
 895                 ivtv_irq_enc_vbi_cap(itv);
 896         }
 897
 898         if (combo & IVTV_IRQ_DEC_VBI_RE_INSERT) {
 899                 ivtv_irq_dec_vbi_reinsert(itv);
 900         }
 901
 902         if (combo & IVTV_IRQ_ENC_EOS) {
 903                 IVTV_DEBUG_IRQ("ENC EOS\n");
 904                 set_bit(IVTV_F_I_EOS, &itv->i_flags);
 905                 wake_up(&itv->eos_waitq);
 906         }
 907
 908         if (combo & IVTV_IRQ_DEC_DATA_REQ) {
 909                 ivtv_irq_dec_data_req(itv);
 910         }
 911
 912         /* Decoder Vertical Sync - We can't rely on 'combo', so check if vsync enabled */
 913         if (~itv->irqmask & IVTV_IRQ_DEC_VSYNC) {
 914                 ivtv_irq_vsync(itv);
 915         }
 916
 917         if (combo & IVTV_IRQ_ENC_VIM_RST) {
 918                 IVTV_DEBUG_IRQ("VIM RST\n");
 919                 /*ivtv_vapi(itv, CX2341X_ENC_REFRESH_INPUT, 0); */
 920         }
 921
 922         if (combo & IVTV_IRQ_DEC_AUD_MODE_CHG) {
 923                 IVTV_DEBUG_INFO("Stereo mode changed\n");
 924         }
 925
 926         if ((combo & IVTV_IRQ_DMA) && !test_bit(IVTV_F_I_DMA, &itv->i_flags)) {
 927                 itv->irq_rr_idx++;
 928                 for (i = 0; i < IVTV_MAX_STREAMS; i++) {
 929                         int idx = (i + itv->irq_rr_idx) % IVTV_MAX_STREAMS;
 930                         struct ivtv_stream *s = &itv->streams[idx];
 931
 932                         if (!test_and_clear_bit(IVTV_F_S_DMA_PENDING, &s->s_flags))
 933                                 continue;
 934                         if (s->type >= IVTV_DEC_STREAM_TYPE_MPG)
 935                                 ivtv_dma_dec_start(s);
 936                         else
 937                                 ivtv_dma_enc_start(s);
 938                         break;
 939                 }
 940                 if (i == IVTV_MAX_STREAMS && test_and_clear_bit(IVTV_F_I_UDMA_PENDING, &itv->i_flags)) {
 941                         ivtv_udma_start(itv);
 942                 }
 943         }
 944
 945         if ((combo & IVTV_IRQ_DMA) && !test_bit(IVTV_F_I_PIO, &itv->i_flags)) {
 946                 itv->irq_rr_idx++;
 947                 for (i = 0; i < IVTV_MAX_STREAMS; i++) {
 948                         int idx = (i + itv->irq_rr_idx) % IVTV_MAX_STREAMS;
 949                         struct ivtv_stream *s = &itv->streams[idx];
 950
 951                         if (!test_and_clear_bit(IVTV_F_S_PIO_PENDING, &s->s_flags))
 952                                 continue;
 953                         if (s->type == IVTV_DEC_STREAM_TYPE_VBI || s->type < IVTV_DEC_STREAM_TYPE_MPG)
 954                                 ivtv_dma_enc_start(s);
 955                         break;
 956                 }
 957         }
 958
 959         if (test_and_clear_bit(IVTV_F_I_HAVE_WORK, &itv->i_flags)) {
 960                 queue_work(itv->irq_work_queues, &itv->irq_work_queue);
 961         }
 962
 963         spin_unlock(&itv->dma_reg_lock);
 964
 965         /* If we've just handled a 'forced' vsync, it's safest to say it
 966          * wasn't ours. Another device may have triggered it at just
 967          * the right time.
 968          */
 969         return vsync_force ? IRQ_NONE : IRQ_HANDLED;
 970 }
 971
 972 void ivtv_unfinished_dma(unsigned long arg)
 973 {
 974         struct ivtv *itv = (struct ivtv *)arg;
 975
 976         if (!test_bit(IVTV_F_I_DMA, &itv->i_flags))
 977                 return;
 978         IVTV_ERR("DMA TIMEOUT %08x %d\n", read_reg(IVTV_REG_DMASTATUS), itv->cur_dma_stream);
 979
 980         write_reg(read_reg(IVTV_REG_DMASTATUS) & 3, IVTV_REG_DMASTATUS);
 981         clear_bit(IVTV_F_I_UDMA, &itv->i_flags);
 982         clear_bit(IVTV_F_I_DMA, &itv->i_flags);
 983         itv->cur_dma_stream = -1;
 984         wake_up(&itv->dma_waitq);
 985 }