dmabuf.c

freebsd v4.4内核源码

     * defined by the process.
   */

  max = dmap->max_fragments;
  len = dmap->qlen;

  if (audio_devs[dev]->local_qlen)
    {
      tmp = audio_devs[dev]->local_qlen (dev);
      if (tmp & len)
	tmp--;			/*
				   * This buffer has been counted twice
				 */
      len += tmp;
    }

  if (len >= max)
    return 0;
  return 1;
}

int
DMAbuf_getwrbuffer (int dev, char **buf, int *size, int dontblock)
{
  unsigned long   flags;
  int             abort, err = EIO;
  struct dma_buffparms *dmap = audio_devs[dev]->dmap;

  if (dmap->dma_mode == DMODE_INPUT)	/* Direction change */
    {
      dma_reset (dev);
      dmap->dma_mode = DMODE_NONE;
    }
  else if (dmap->flags & DMA_RESTART)	/* Restart buffering */
    {
      dma_sync (dev);
      dma_reset (dev);
    }

  dmap->flags &= ~DMA_RESTART;

  if (!(dmap->flags & DMA_ALLOC_DONE))
    reorganize_buffers (dev);

  if (!dmap->dma_mode)
    {
      int             err;

      dmap->dma_mode = DMODE_OUTPUT;
      if ((err = audio_devs[dev]->prepare_for_output (dev,
				     dmap->fragment_size, dmap->nbufs)) < 0)
	return err;
    }

  DISABLE_INTR (flags);

  abort = 0;
  while (!space_in_queue (dev) &&
	 !abort)
    {

      if (dontblock)
	{
	  RESTORE_INTR (flags);
	  return RET_ERROR (EAGAIN);
	}

      /*
       * Wait for free space
       */
      DO_SLEEP (dev_sleeper[dev], dev_sleep_flag[dev], 2 * HZ);
      if (TIMED_OUT (dev_sleeper[dev], dev_sleep_flag[dev]))
	{
	  printk ("Sound: DMA timed out - IRQ/DRQ config error?\n");
	  dma_reset (dev);
	  err = EIO;
	  abort = 1;
	  SET_ABORT_FLAG (dev_sleeper[dev], dev_sleep_flag[dev]);
	}
      else if (PROCESS_ABORTING (dev_sleeper[dev], dev_sleep_flag[dev]))
	{
	  err = EINTR;
	  abort = 1;
	}
    }
  RESTORE_INTR (flags);

  if (!space_in_queue (dev))
    {
      return RET_ERROR (err);	/* Caught a signal ? */
    }

  *buf = dmap->buf[dmap->qtail];
  *size = dmap->fragment_size;
  dmap->counts[dmap->qtail] = 0;

  return dmap->qtail;
}

int
DMAbuf_start_output (int dev, int buff_no, int l)
{
  struct dma_buffparms *dmap = audio_devs[dev]->dmap;

  if (buff_no != dmap->qtail)
    printk ("Sound warning: DMA buffers out of sync %d != %d\n", buff_no, dmap->qtail);

  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) &&
      ((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;
      audio_devs[dev]->output_block (dev, dmap->buf_phys[dmap->qhead],
				     dmap->counts[dmap->qhead], 0,
				 !(audio_devs[dev]->flags & DMA_AUTOMODE) ||
				     !(dmap->flags & DMA_STARTED));
      dmap->flags |= DMA_STARTED;
    }

  return 0;
}

int
DMAbuf_start_dma (int dev, unsigned long physaddr, int count, int dma_mode)
{
  int             chan = audio_devs[dev]->dmachan;
  struct dma_buffparms *dmap = audio_devs[dev]->dmap;
#ifdef linux
  unsigned long   flags;
#endif
  /*
   * This function is not as portable as it should be.
   */

  /*
   * 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
				 */
#ifdef linux
      DISABLE_INTR (flags);
      disable_dma (chan);
      clear_dma_ff (chan);
      set_dma_mode (chan, dma_mode | DMA_AUTOINIT);
      set_dma_addr (chan, dmap->raw_buf_phys[0]);
      set_dma_count (chan, dmap->bytes_in_use);
      enable_dma (chan);
      RESTORE_INTR (flags);
#else

#if defined(__FreeBSD__)

      isa_dmastart (B_RAW | ((dma_mode == DMA_MODE_READ) ? B_READ : B_WRITE),
		    (caddr_t)dmap->raw_buf_phys[0],
		    dmap->bytes_in_use,
		    chan);
#else /* else __FreeBSD__ */
#if defined(GENERIC_SYSV)
#ifndef DMAMODE_AUTO
      printk ("sound: Invalid DMA mode for device %d\n", dev);
#endif
#if defined(SVR42)

      /*
         ** send full count to snd_dma_prog, it will take care of subtracting
         ** one if it is required.
       */
      snd_dma_prog (chan, dmap->raw_buf_phys[0], dmap->bytes_in_use,
		    dma_mode, TRUE);

#else /* !SVR42 */
      dma_param (chan, ((dma_mode == DMA_MODE_READ) ? DMA_Rdmode : DMA_Wrmode)
#ifdef DMAMODE_AUTO
		 | DMAMODE_AUTO
#endif
		 ,
		 dmap->raw_buf_phys[0], dmap->bytes_in_use - 1);
      dma_enable (chan);
#endif /*  ! SVR42 */
#else
#error This routine is not valid for this OS.
#endif
#endif

#endif
    }
  else
    {
#ifdef linux
      DISABLE_INTR (flags);
      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_INTR (flags);
#else
#if defined(__FreeBSD__)
      isa_dmastart ((dma_mode == DMA_MODE_READ) ? B_READ : B_WRITE,
		    (caddr_t)physaddr,
		    count,
		    chan);
#else /* FreeBSD */

#if defined(GENERIC_SYSV)
#if defined(SVR42)

      snd_dma_prog (chan, physaddr, count, dma_mode, FALSE);

#else /* ! SVR42 */
      dma_param (chan, ((dma_mode == DMA_MODE_READ) ? DMA_Rdmode : DMA_Wrmode),
		 physaddr, count);
      dma_enable (chan);
#endif /* SVR42 */
#else
#error This routine is not valid for this OS.
#endif /* GENERIC_SYSV */
#endif

#endif
    }

  return count;
}

long
DMAbuf_init (long mem_start)
{
  int             dev;

#if defined(SVR42)
  snd_dma_init ();
#endif /* SVR42 */

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

  for (dev = 0; dev < num_audiodevs; dev++)
    audio_devs[dev]->dmap = &dmaps[dev];
  return mem_start;
}

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;

#if defined(SVR42)
  snd_dma_intr (audio_devs[dev]->dmachan);
#endif /* SVR42 */

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

#ifdef __FreeBSD__
      isa_dmadone(0, 0, 0, audio_devs[dev]->dmachan);
#endif

      if (dmap->qlen)
	{
	  audio_devs[dev]->output_block (dev, dmap->buf_phys[dmap->qhead],
					 dmap->counts[dmap->qhead], 1,
				  !(audio_devs[dev]->flags & DMA_AUTOMODE));
	  dmap->flags |= DMA_ACTIVE;
	}
      else if (event_type == 1)
	{
	  dmap->underrun_count++;
	  audio_devs[dev]->halt_xfer (dev);
	  if ((audio_devs[dev]->flags & DMA_AUTOMODE) &&
	      audio_devs[dev]->flags & NEEDS_RESTART)
	    dmap->flags |= DMA_RESTART;
	  else
	    dmap->flags &= ~DMA_RESTART;
	}
    }				/* event_type != 2 */

  DISABLE_INTR (flags);
  if (SOMEONE_WAITING (dev_sleeper[dev], dev_sleep_flag[dev]))
    {
      WAKE_UP (dev_sleeper[dev], dev_sleep_flag[dev]);
    }
  RESTORE_INTR (flags);
#if defined(__FreeBSD__)
  if(selinfo[dev].si_pid)
    selwakeup(&selinfo[dev]);
#endif
}

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

#if defined(SVR42)
  snd_dma_intr (audio_devs[dev]->dmachan);
#endif /* SVR42 */
 
#ifdef __FreeBSD__
      isa_dmadone(0, 0, 0, audio_devs[dev]->dmachan);
#endif

  if (dmap->qlen == (dmap->nbufs - 1))
    {
#if !defined(__FreeBSD__)	/* ignore console message. */
      printk ("Sound: Recording overrun\n");
#endif
      dmap->underrun_count++;
      audio_devs[dev]->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;

      audio_devs[dev]->start_input (dev, dmap->buf_phys[dmap->qtail],
				    dmap->fragment_size, 1,
				  !(audio_devs[dev]->flags & DMA_AUTOMODE));
      dmap->flags |= DMA_ACTIVE;
    }

  DISABLE_INTR (flags);
  if (SOMEONE_WAITING (dev_sleeper[dev], dev_sleep_flag[dev]))
    {
      WAKE_UP (dev_sleeper[dev], dev_sleep_flag[dev]);
    }
  RESTORE_INTR (flags);
#if defined(__FreeBSD__)
  if(selinfo[dev].si_pid)
    selwakeup(&selinfo[dev]);
#endif
}

int
DMAbuf_open_dma (int dev)
{
  unsigned long   flags;
  int             chan = audio_devs[dev]->dmachan;

  if (ALLOC_DMA_CHN (chan, audio_devs[dev]->name))
    {
#if 0
      /* Enough already!  This error is reported twice elsewhere */
      printk ("Unable to grab DMA%d for the audio driver\n", chan);
#endif
      return RET_ERROR (EBUSY);
    }

  DISABLE_INTR (flags);
#ifdef linux
  disable_dma (chan);
  clear_dma_ff (chan);
#endif
  RESTORE_INTR (flags);

  return 0;
}

void
DMAbuf_close_dma (int dev)
{
  int             chan = audio_devs[dev]->dmachan;

  DMAbuf_reset_dma (dev);
  RELEASE_DMA_CHN (chan);
}

void
DMAbuf_reset_dma (int dev)
{
}

#ifdef ALLOW_SELECT
int
DMAbuf_select (int dev, struct fileinfo *file, int sel_type, select_table * wait)
{
  struct dma_buffparms *dmap = audio_devs[dev]->dmap;
  unsigned long   flags;

  switch (sel_type)
    {
    case SEL_IN:
      if (dmap->dma_mode != DMODE_INPUT)
	return 0;

      DISABLE_INTR (flags);
      if (!dmap->qlen)
	{
#if defined(__FreeBSD__)
	  selrecord(wait, &selinfo[dev]);
#else
	  dev_sleep_flag[dev].mode = WK_SLEEP;
	  select_wait (&dev_sleeper[dev], wait);
#endif
	  RESTORE_INTR (flags);
	  return 0;
	}
      RESTORE_INTR (flags);
      return 1;
      break;

    case SEL_OUT:
      if (dmap->dma_mode == DMODE_INPUT)
	return 0;

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

      DISABLE_INTR (flags);
      if (!space_in_queue (dev))
	{
#if defined(__FreeBSD__)
	  selrecord(wait, &selinfo[dev]);
#else
	  dev_sleep_flag[dev].mode = WK_SLEEP;
	  select_wait (&dev_sleeper[dev], wait);
#endif
	  RESTORE_INTR (flags);
	  return 0;
	}
      RESTORE_INTR (flags);
      return 1;
      break;

    case SEL_EX:
      return 0;
    }

  return 0;
}

#endif /* ALLOW_SELECT */

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

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

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

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

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

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

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

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

long
DMAbuf_init (long mem_start)
{
  return mem_start;
}

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

int
DMAbuf_open_dma (int dev)
{
  return RET_ERROR (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

#endif