Re: [PATCH V3 4/9] ASoC: amd: ps: add SoundWire dma driver dma ops

[Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>]

> +static int acp63_sdw_dma_start(struct snd_pcm_substream *substream, void __iomem *acp_base)
> +{
> +	struct acp_sdw_dma_stream *stream;
> +	u32 stream_id;
> +	u32 sdw_dma_en_reg;
> +	u32 sdw_dma_en_stat_reg;
> +	u32 sdw_dma_stat;
> +
> +	stream = substream->runtime->private_data;
> +	stream_id = stream->stream_id;
> +	switch (stream->instance) {
> +	case ACP_SDW0:
> +		sdw_dma_en_reg = sdw0_dma_enable_reg[stream_id];
> +		break;
> +	case ACP_SDW1:
> +		sdw_dma_en_reg = sdw1_dma_enable_reg[stream_id];
> +		break;
> +	default:
> +		return -EINVAL;
> +	}
> +	writel(0x01, acp_base + sdw_dma_en_reg);
> +	sdw_dma_en_stat_reg = sdw_dma_en_reg + 4;
> +	return readl_poll_timeout(acp_base + sdw_dma_en_stat_reg, sdw_dma_stat,
> +				  (sdw_dma_stat & BIT(0)), ACP_DELAY_US, ACP_COUNTER);
> +}
> +
> +static int acp63_sdw_dma_stop(struct snd_pcm_substream *substream, void __iomem *acp_base)
> +{
> +	struct acp_sdw_dma_stream *stream;
> +	u32 stream_id;
> +	u32 sdw_dma_en_reg;
> +	u32 sdw_dma_en_stat_reg;
> +	u32 sdw_dma_stat;
> +
> +	stream = substream->runtime->private_data;
> +	stream_id = stream->stream_id;
> +	switch (stream->instance) {
> +	case ACP_SDW0:
> +		sdw_dma_en_reg = sdw0_dma_enable_reg[stream_id];
> +		break;
> +	case ACP_SDW1:
> +		sdw_dma_en_reg = sdw1_dma_enable_reg[stream_id];
> +		break;
> +	default:
> +		return -EINVAL;
> +	}
> +
> +	writel(0, acp_base + sdw_dma_en_reg);
> +	sdw_dma_en_stat_reg = sdw_dma_en_reg + 4;
> +	return readl_poll_timeout(acp_base + sdw_dma_en_stat_reg, sdw_dma_stat, !sdw_dma_stat,
> +				  ACP_DELAY_US, ACP_COUNTER);
> +}

these start/stop routines look mostly the same, except for the value to
be written in the register. Maybe they can be factored with a common
helper, e.g. acp63_sdw_dma_enable(true/false).
> +
> +static int acp63_sdw_dma_trigger(struct snd_soc_component *comp,
> +				 struct snd_pcm_substream *substream,
> +				 int cmd)
> +{
> +	struct sdw_dma_dev_data *sdw_data;
> +	int ret;
> +
> +	sdw_data = dev_get_drvdata(comp->dev);
> +	switch (cmd) {
> +	case SNDRV_PCM_TRIGGER_START:
> +	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
> +	case SNDRV_PCM_TRIGGER_RESUME:
> +		ret = acp63_sdw_dma_start(substream, sdw_data->acp_base);
> +		break;
> +	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
> +	case SNDRV_PCM_TRIGGER_SUSPEND:
> +	case SNDRV_PCM_TRIGGER_STOP:
> +		ret = acp63_sdw_dma_stop(substream, sdw_data->acp_base);
> +		break;
> +	default:
> +		ret = -EINVAL;
> +	}
> +	if (ret)
> +		dev_err(comp->dev, "trigger %d failed: %d", cmd, ret);
> +	return ret;
> +}