dmabuf.c

arm平台上的uclinux系统全部源代码

      dmap->qtail = (dmap->qtail + 1) % dmap->nbufs;
    }
  else
    {

      dmap->qlen++;
      if (dmap->qlen <= 0 || dmap->qlen > dmap->nbufs)
	printk ("\nSound: Audio queue2 corrupted for dev%d (%d/%d)\n",
		dev, dmap->qlen, dmap->nbufs);

      dmap->counts[dmap->qtail] = l;
      if (l < dmap->fragment_size)
	{
	  int             p = dmap->fragment_size * dmap->qtail;

	  dmap->neutral_byte = dmap->raw_buf[p + l - 1];

	  memset (dmap->raw_buf + p + l,
		  dmap->neutral_byte,
		  dmap->fragment_size - l);
	}
      else
	dmap->neutral_byte =
	  dmap->raw_buf[dmap->fragment_size * dmap->qtail - 1];

      if ((l != dmap->fragment_size) &&
	  ((audio_devs[dev]->flags & DMA_AUTOMODE) &&
	   audio_devs[dev]->flags & NEEDS_RESTART))
	dmap->flags |= DMA_RESTART;
      else
	dmap->flags &= ~DMA_RESTART;

      dmap->qtail = (dmap->qtail + 1) % dmap->nbufs;
    }

  if (!(dmap->flags & DMA_ACTIVE))
    {
      dmap->flags |= DMA_ACTIVE;

      if (restart)
	audio_devs[dev]->d->prepare_for_output (dev,
					  dmap->fragment_size, dmap->nbufs);

      audio_devs[dev]->d->output_block (dev, dmap->raw_buf_phys +
					dmap->qhead * dmap->fragment_size,
					dmap->counts[dmap->qhead], 0,
				 !(audio_devs[dev]->flags & DMA_AUTOMODE) ||
					!(dmap->flags & DMA_STARTED));
      dmap->flags |= DMA_STARTED;
      if (audio_devs[dev]->d->trigger)
	audio_devs[dev]->d->trigger (dev,
			audio_devs[dev]->enable_bits * audio_devs[dev]->go);
    }

  return 0;
}

int
DMAbuf_start_dma (int dev, unsigned long physaddr, int count, int dma_mode)
{
  int             chan;
  struct dma_buffparms *dmap;
  unsigned long   flags;

  if (dma_mode == DMA_MODE_WRITE)
    {
      chan = audio_devs[dev]->dmachan1;
      dmap = audio_devs[dev]->dmap_out;
    }
  else
    {
      chan = audio_devs[dev]->dmachan2;
      dmap = audio_devs[dev]->dmap_in;
    }

  if (dmap->raw_buf_phys == 0)
    {
      printk ("sound: DMA buffer == NULL\n");
      return 0;
    }

  /*
   * The count must be one less than the actual size. This is handled by
   * set_dma_addr()
   */

  if (audio_devs[dev]->flags & DMA_AUTOMODE)
    {				/*
				 * Auto restart mode. Transfer the whole *
				 * buffer
				 */
      save_flags (flags);
      cli ();
      disable_dma (chan);
      clear_dma_ff (chan);
      set_dma_mode (chan, dma_mode | DMA_AUTOINIT);
      set_dma_addr (chan, dmap->raw_buf_phys);
      set_dma_count (chan, dmap->bytes_in_use);
      enable_dma (chan);
      restore_flags (flags);
    }
  else
    {
      save_flags (flags);
      cli ();
      disable_dma (chan);
      clear_dma_ff (chan);
      set_dma_mode (chan, dma_mode);
      set_dma_addr (chan, physaddr);
      set_dma_count (chan, count);
      enable_dma (chan);
      restore_flags (flags);
    }

  return count;
}

void
DMAbuf_init (void)
{
  int             dev;


  /*
     * NOTE! This routine could be called several times.
   */

  for (dev = 0; dev < num_audiodevs; dev++)
    if (audio_devs[dev]->dmap_out == NULL)
      {
	audio_devs[dev]->dmap_out =
	  audio_devs[dev]->dmap_in =
	  &dmaps[ndmaps++];

	if (audio_devs[dev]->flags & DMA_DUPLEX)
	  audio_devs[dev]->dmap_in =
	    &dmaps[ndmaps++];
      }
}

static void
polish_buffers (struct dma_buffparms *dmap)
{
  int             i;
  int             p, l;

  i = dmap->qhead;

  p = dmap->fragment_size * i;

  if (i == dmap->cfrag)
    {
      l = dmap->fragment_size - dmap->counts[i];
    }
  else
    l = dmap->fragment_size;

  if (l)
    {
      memset (dmap->raw_buf + p,
	      dmap->neutral_byte,
	      l);
    }
}

static void
force_restart (int dev, struct dma_buffparms *dmap)
{
  if ((audio_devs[dev]->flags & DMA_DUPLEX) &&
      audio_devs[dev]->d->halt_output)
    audio_devs[dev]->d->halt_output (dev);
  else
    audio_devs[dev]->d->halt_xfer (dev);

  dmap->flags &= ~(DMA_ACTIVE | DMA_STARTED);
  if (audio_devs[dev]->flags & DMA_AUTOMODE)
    dmap->flags |= DMA_RESTART;
  else
    dmap->flags &= ~DMA_RESTART;
}

void
DMAbuf_outputintr (int dev, int event_type)
{
  /*
     * Event types:
     *  0 = DMA transfer done. Device still has more data in the local
     *      buffer.
     *  1 = DMA transfer done. Device doesn't have local buffer or it's
     *      empty now.
     *  2 = No DMA transfer but the device has now more space in it's local
     *      buffer.
   */

  unsigned long   flags;
  struct dma_buffparms *dmap = audio_devs[dev]->dmap_out;
  int             this_fragment;

  dmap->byte_counter += dmap->counts[dmap->qhead];

#ifdef OS_DMA_INTR
  sound_dma_intr (dev, audio_devs[dev]->dmap_out, audio_devs[dev]->dmachan1);
#endif

  if (dmap->raw_buf == NULL)
    {
      printk ("Sound: Fatal error. Audio interrupt after freeing buffers.\n");
      return;
    }

  if (dmap->mapping_flags & DMA_MAP_MAPPED)
    {
      /* mmapped access */
      dmap->qhead = (dmap->qhead + 1) % dmap->nbufs;
      dmap->qlen++;		/* Yes increment it (don't decrement) */
      dmap->flags &= ~DMA_ACTIVE;
      dmap->counts[dmap->qhead] = dmap->fragment_size;

      if (!(audio_devs[dev]->flags & DMA_AUTOMODE))
	{
	  audio_devs[dev]->d->output_block (dev, dmap->raw_buf_phys +
					  dmap->qhead * dmap->fragment_size,
					    dmap->counts[dmap->qhead], 1,
				  !(audio_devs[dev]->flags & DMA_AUTOMODE));
	  if (audio_devs[dev]->d->trigger)
	    audio_devs[dev]->d->trigger (dev,
			audio_devs[dev]->enable_bits * audio_devs[dev]->go);
	}
      dmap->flags |= DMA_ACTIVE;
    }
  else if (event_type != 2)
    {
      if (dmap->qlen <= 0 || dmap->qlen > dmap->nbufs)
	{
	  printk ("\nSound: Audio queue3 corrupted for dev%d (%d/%d)\n",
		  dev, dmap->qlen, dmap->nbufs);
	  return;
	}

      dmap->qlen--;
      this_fragment = dmap->qhead;
      dmap->qhead = (dmap->qhead + 1) % dmap->nbufs;
      dmap->flags &= ~DMA_ACTIVE;

      if (event_type == 1 && dmap->qlen < 1)
	{
	  dmap->underrun_count++;

	  if ((!(dmap->flags & DMA_CLEAN) &&
	       (audio_devs[dev]->dmap_out->flags & DMA_SYNCING ||
		dmap->underrun_count > 5 || dmap->flags & DMA_EMPTY)) ||
	      audio_devs[dev]->flags & DMA_HARDSTOP)

	    {
	      dmap->qlen = 0;
	      force_restart (dev, dmap);
	    }
	  else
	    /* Ignore underrun. Just move the tail pointer forward and go */
	  if (dmap->closing)
	    {
	      polish_buffers (dmap);
	      audio_devs[dev]->d->halt_xfer (dev);
	    }
	  else
	    {
	      dmap->qlen++;
	      dmap->qtail = (dmap->qtail + 1) % dmap->nbufs;

	      if (!(dmap->flags & DMA_EMPTY))
		polish_buffers (dmap);

	      dmap->cfrag = -1;
	      dmap->flags |= DMA_EMPTY;
	      dmap->counts[dmap->qtail] = dmap->fragment_size;
	    }
	}

      if (dmap->qlen)
	{
	  if (dmap->flags & DMA_CLEAN)
	    {
	      int             p = dmap->fragment_size * this_fragment;

	      memset (dmap->raw_buf + p,
		      dmap->neutral_byte,
		      dmap->fragment_size);
	    }

	  if (!(audio_devs[dev]->flags & DMA_AUTOMODE))
	    {

	      if (dmap->counts[dmap->qhead] == 0)
		dmap->counts[dmap->qhead] = dmap->fragment_size;

	      audio_devs[dev]->d->output_block (dev, dmap->raw_buf_phys +
					  dmap->qhead * dmap->fragment_size,
						dmap->counts[dmap->qhead], 1,
				  !(audio_devs[dev]->flags & DMA_AUTOMODE));
	      if (audio_devs[dev]->d->trigger)
		audio_devs[dev]->d->trigger (dev,
			audio_devs[dev]->enable_bits * audio_devs[dev]->go);
	    }
	  dmap->flags |= DMA_ACTIVE;
	}
    }				/* event_type != 2 */

  save_flags (flags);
  cli ();
  if ((out_sleep_flag[dev].flags & WK_SLEEP))
    {
      {
	out_sleep_flag[dev].flags = WK_WAKEUP;
	module_wake_up (&out_sleeper[dev]);
      };
    }
  restore_flags (flags);
}

void
DMAbuf_inputintr (int dev)
{
  unsigned long   flags;
  struct dma_buffparms *dmap = audio_devs[dev]->dmap_in;

  dmap->byte_counter += dmap->fragment_size;

#ifdef OS_DMA_INTR
  sound_dma_intr (dev, audio_devs[dev]->dmap_in, audio_devs[dev]->dmachan2);
#endif

  if (dmap->raw_buf == NULL)
    {
      printk ("Sound: Fatal error. Audio interrupt after freeing buffers.\n");
      return;
    }

  if (dmap->mapping_flags & DMA_MAP_MAPPED)
    {
      dmap->qtail = (dmap->qtail + 1) % dmap->nbufs;
      dmap->qlen++;

      if (!(audio_devs[dev]->flags & DMA_AUTOMODE))
	{
	  audio_devs[dev]->d->start_input (dev, dmap->raw_buf_phys +
					   dmap->qtail * dmap->fragment_size,
					   dmap->fragment_size, 1,
				  !(audio_devs[dev]->flags & DMA_AUTOMODE));
	  if (audio_devs[dev]->d->trigger)
	    audio_devs[dev]->d->trigger (dev,
			audio_devs[dev]->enable_bits * audio_devs[dev]->go);
	}

      dmap->flags |= DMA_ACTIVE;
    }
  else if (dmap->qlen == (dmap->nbufs - 1))
    {
      printk ("Sound: Recording overrun\n");
      dmap->underrun_count++;

      if (audio_devs[dev]->flags & DMA_AUTOMODE)
	{
	  /* Force restart on next read */
	  if ((audio_devs[dev]->flags & DMA_DUPLEX) &&
	      audio_devs[dev]->d->halt_input)
	    audio_devs[dev]->d->halt_input (dev);
	  else
	    audio_devs[dev]->d->halt_xfer (dev);

	  dmap->flags &= ~DMA_ACTIVE;
	  if (audio_devs[dev]->flags & DMA_AUTOMODE)
	    dmap->flags |= DMA_RESTART;
	  else
	    dmap->flags &= ~DMA_RESTART;
	}
    }
  else
    {
      dmap->qlen++;
      if (dmap->qlen <= 0 || dmap->qlen > dmap->nbufs)
	printk ("\nSound: Audio queue4 corrupted for dev%d (%d/%d)\n",
		dev, dmap->qlen, dmap->nbufs);
      dmap->qtail = (dmap->qtail + 1) % dmap->nbufs;
    }

  if (!(audio_devs[dev]->flags & DMA_AUTOMODE))
    {
      audio_devs[dev]->d->start_input (dev, dmap->raw_buf_phys +
				       dmap->qtail * dmap->fragment_size,
				       dmap->fragment_size, 1,
				  !(audio_devs[dev]->flags & DMA_AUTOMODE));
      if (audio_devs[dev]->d->trigger)
	audio_devs[dev]->d->trigger (dev,
			audio_devs[dev]->enable_bits * audio_devs[dev]->go);
    }

  dmap->flags |= DMA_ACTIVE;

  save_flags (flags);
  cli ();
  if ((in_sleep_flag[dev].flags & WK_SLEEP))
    {
      {
	in_sleep_flag[dev].flags = WK_WAKEUP;
	module_wake_up (&in_sleeper[dev]);
      };
    }
  restore_flags (flags);
}

int
DMAbuf_open_dma (int dev)
{
/*
 *    NOTE!  This routine opens only the primary DMA channel (output).
 */

  int             chan = audio_devs[dev]->dmachan1;
  int             err;
  unsigned long   flags;

  if ((err = open_dmap (dev, OPEN_READWRITE, audio_devs[dev]->dmap_out, audio_devs[dev]->dmachan1)) < 0)
    {
      return -(EBUSY);
    }
  dma_init_buffers (dev, audio_devs[dev]->dmap_out);
  audio_devs[dev]->dmap_out->flags |= DMA_ALLOC_DONE;
  audio_devs[dev]->dmap_out->fragment_size = audio_devs[dev]->buffsize;

  save_flags (flags);
  cli ();
  disable_dma (chan);
  clear_dma_ff (chan);
  restore_flags (flags);

  return 0;
}

void
DMAbuf_close_dma (int dev)
{
  DMAbuf_reset_dma (dev);
  close_dmap (dev, audio_devs[dev]->dmap_out, audio_devs[dev]->dmachan1);
}

void
DMAbuf_reset_dma (int dev)
{
}

int
DMAbuf_select (int dev, struct fileinfo *file, int sel_type, select_table_handle * wait)
{
  struct dma_buffparms *dmap;
  unsigned long   flags;

  switch (sel_type)
    {
    case SEL_IN:
      dmap = audio_devs[dev]->dmap_in;

      if (dmap->mapping_flags & DMA_MAP_MAPPED)
	{
	  if (dmap->qlen)
	    return 1;

	  save_flags (flags);
	  cli ();

	  in_sleep_flag[dev].flags = WK_SLEEP;
	  module_select_wait (&in_sleeper[dev], wait);
	  restore_flags (flags);
	  return 0;
	}

      if (dmap->dma_mode != DMODE_INPUT)
	{
	  if ((audio_devs[dev]->flags & DMA_DUPLEX) && !dmap->qlen &&
	      audio_devs[dev]->enable_bits & PCM_ENABLE_INPUT &&
	      audio_devs[dev]->go)
	    {
	      unsigned long   flags;

	      save_flags (flags);
	      cli ();
	      activate_recording (dev, dmap);
	      restore_flags (flags);
	    }
	  return 0;
	}

      if (!dmap->qlen)
	{
	  save_flags (flags);
	  cli ();

	  in_sleep_flag[dev].flags = WK_SLEEP;
	  module_select_wait (&in_sleeper[dev], wait);
	  restore_flags (flags);
	  return 0;
	}
      return 1;
      break;

    case SEL_OUT:
      dmap = audio_devs[dev]->dmap_out;

      if (dmap->mapping_flags & DMA_MAP_MAPPED)
	{
	  if (dmap->qlen)
	    return 1;

	  save_flags (flags);
	  cli ();

	  out_sleep_flag[dev].flags = WK_SLEEP;
	  module_select_wait (&out_sleeper[dev], wait);
	  restore_flags (flags);
	  return 0;
	}

      if (dmap->dma_mode == DMODE_INPUT)
	{
	  return 0;
	}

      if (dmap->dma_mode == DMODE_NONE)
	{
	  return 1;
	}

      if (!space_in_queue (dev))
	{
	  save_flags (flags);
	  cli ();

	  out_sleep_flag[dev].flags = WK_SLEEP;
	  module_select_wait (&out_sleeper[dev], wait);
	  restore_flags (flags);
	  return 0;
	}
      return 1;
      break;

    case SEL_EX:
      return 0;
    }

  return 0;
}


#else /* CONFIG_AUDIO */
/*
 * Stub versions if audio services not included
 */

int
DMAbuf_open (int dev, int mode)
{
  return -(ENXIO);
}

int
DMAbuf_release (int dev, int mode)
{
  return 0;
}

int
DMAbuf_getwrbuffer (int dev, char **buf, int *size, int dontblock)
{
  return -(EIO);
}

int
DMAbuf_getrdbuffer (int dev, char **buf, int *len, int dontblock)
{
  return -(EIO);
}

int
DMAbuf_rmchars (int dev, int buff_no, int c)
{
  return -(EIO);
}

int
DMAbuf_start_output (int dev, int buff_no, int l)
{
  return -(EIO);
}

int
DMAbuf_ioctl (int dev, unsigned int cmd, caddr_t arg, int local)
{
  return -(EIO);
}

void
DMAbuf_init (void)
{
}

int
DMAbuf_start_dma (int dev, unsigned long physaddr, int count, int dma_mode)
{
  return -(EIO);
}

int
DMAbuf_open_dma (int dev)
{
  return -(ENXIO);
}

void
DMAbuf_close_dma (int dev)
{
  return;
}

void
DMAbuf_reset_dma (int dev)
{
  return;
}

void
DMAbuf_inputintr (int dev)
{
  return;
}

void
DMAbuf_outputintr (int dev, int underrun_flag)
{
  return;
}
#endif