linux-2.6.33/snd_pcm_period_elapsed() の履歴(No.1)

• 履歴一覧
• 差分 を表示
• 現在との差分 を表示
• ソース を表示
• linux-2.6.33/snd_pcm_period_elapsed() へ行く。
  • 1 (2013-06-20 (木) 20:43:48)

参照元†

説明†

• パス: linux-2.6.33/sound/core/pcm_lib.c

• FIXME: これは何？
  • 説明

引数†

• struct snd_pcm_substream *substream

返り値†

• なし

参考†

実装†

/**
 * snd_pcm_period_elapsed - update the pcm status for the next period
 * @substream: the pcm substream instance
 *
 * This function is called from the interrupt handler when the
 * PCM has processed the period size.  It will update the current
 * pointer, wake up sleepers, etc.
 *
 * Even if more than one periods have elapsed since the last call, you
 * have to call this only once.
 */
void snd_pcm_period_elapsed(struct snd_pcm_substream *substream)
{
	struct snd_pcm_runtime *runtime;
	unsigned long flags;

• • [[linux-2.6.33/]]

	if (PCM_RUNTIME_CHECK(substream))
		return;
	runtime = substream->runtime;

• • linux-2.6.33/PCM_RUNTIME_CHECK()

	if (runtime->transfer_ack_begin)
		runtime->transfer_ack_begin(substream);

	snd_pcm_stream_lock_irqsave(substream, flags);
	if (!snd_pcm_running(substream) ||
	    snd_pcm_update_hw_ptr_interrupt(substream) < 0)
		goto _end;

• • linux-2.6.33/snd_pcm_stream_lock_irqsave()

• linux-2.6.33/snd_pcm_running()

• • linux-2.6.33/snd_pcm_update_hw_ptr_interrupt()

	if (substream->timer_running)
		snd_timer_interrupt(substream->timer, 1);

• • linux-2.6.33/snd_timer_interrupt()

 _end:
	snd_pcm_stream_unlock_irqrestore(substream, flags);
	if (runtime->transfer_ack_end)
		runtime->transfer_ack_end(substream);

• • linux-2.6.33/snd_pcm_stream_unlock_irqrestore()

	kill_fasync(&runtime->fasync, SIGIO, POLL_IN);

• • linux-2.6.33/kill_fasync()

}

EXPORT_SYMBOL(snd_pcm_period_elapsed);

• ライセンスに関係なくシンボルを公開する。
  • linux-2.6.33/EXPORT_SYMBOL()

コメント†