C++ (Cpp) AC97PCR_START示例

示例#1

文件： psc-ac97.c 项目： AppEngine/linux-2.6

static int au1xpsc_ac97_trigger(struct snd_pcm_substream *substream,
				int cmd, struct snd_soc_dai *dai)
{
	/* FIXME */
	struct au1xpsc_audio_data *pscdata = au1xpsc_ac97_workdata;
	int ret, stype = SUBSTREAM_TYPE(substream);

	ret = 0;

	switch (cmd) {
	case SNDRV_PCM_TRIGGER_START:
	case SNDRV_PCM_TRIGGER_RESUME:
		au_writel(AC97PCR_START(stype), AC97_PCR(pscdata));
		au_sync();
		break;
	case SNDRV_PCM_TRIGGER_STOP:
	case SNDRV_PCM_TRIGGER_SUSPEND:
		au_writel(AC97PCR_STOP(stype), AC97_PCR(pscdata));
		au_sync();
		break;
	default:
		ret = -EINVAL;
	}
	return ret;
}

示例#2

static int au1xpsc_ac97_trigger(struct snd_pcm_substream *substream,
				int cmd, struct snd_soc_dai *dai)
{
	
	struct au1xpsc_audio_data *pscdata = au1xpsc_ac97_workdata;
	int ret, stype = SUBSTREAM_TYPE(substream);

	ret = 0;

	switch (cmd) {
	case SNDRV_PCM_TRIGGER_START:
	case SNDRV_PCM_TRIGGER_RESUME:
		au_writel(AC97PCR_CLRFIFO(stype), AC97_PCR(pscdata));
		au_sync();
		au_writel(AC97PCR_START(stype), AC97_PCR(pscdata));
		au_sync();
		break;
	case SNDRV_PCM_TRIGGER_STOP:
	case SNDRV_PCM_TRIGGER_SUSPEND:
		au_writel(AC97PCR_STOP(stype), AC97_PCR(pscdata));
		au_sync();

		while (au_readl(AC97_STAT(pscdata)) & AC97STAT_BUSY(stype))
			asm volatile ("nop");

		au_writel(AC97PCR_CLRFIFO(stype), AC97_PCR(pscdata));
		au_sync();

		break;
	default:
		ret = -EINVAL;
	}
	return ret;
}