Re: [PATCH V2 6/9] ASoC: amd: ps: add pm ops support for SoundWire dma driver

From: Pierre-Louis Bossart
Date: Tue May 23 2023 - 14:25:06 EST



>>> @@ -464,16 +488,79 @@ static int acp63_sdw_platform_probe(struct platform_device *pdev)
>>> status = devm_snd_soc_register_component(&pdev->dev,
>>> &acp63_sdw_component,
>>> NULL, 0);
>>> - if (status)
>>> + if (status) {
>>> dev_err(&pdev->dev, "Fail to register sdw dma component\n");
>>> + return status;
>>> + }
>>> + pm_runtime_set_autosuspend_delay(&pdev->dev, ACP_SUSPEND_DELAY_MS);
>>> + pm_runtime_use_autosuspend(&pdev->dev);
>>> + pm_runtime_enable(&pdev->dev);
>>> + pm_runtime_allow(&pdev->dev);
>> Can you remind me why you need the pm_runtime_allow()? I can't recall
>> where the _forbid() is done.
> We have used pm_runtime_allow() to allow the device immediately
> enter runtime suspend state. Yes you are correct. If we use pm_runtime_allow(),
> then in remove sequence we should use pm_runtime_forbid call.
>> Also is there not a pm_runtime_set_active() missing?
>
>
> We will change the sequence as mentioned below.
>
> in probe sequence , we will use
>
>     pm_runtime_set_autosuspend_delay(&pdev->dev, ACP_SUSPEND_DELAY_MS);
>     pm_runtime_use_autosuspend(&pdev->dev);
>     pm_runtime_mark_last_busy(&pdev->dev);
>     pm_runtime_set_active(&pdev->dev);
>     pm_runtime_enable(&pdev->dev);
>
> In remove sequence
>
> pm_runtime_disable(&pdev->dev);

sounds about right.

>>
>>> + return 0;
>>> +}
>>>
>>> - return status;
>>> +static int acp63_sdw_platform_remove(struct platform_device *pdev)
>>> +{
>>> + pm_runtime_disable(&pdev->dev);
>>> + return 0;
>>> }
>>>
>>> +static int __maybe_unused acp63_sdw_pcm_resume(struct device *dev)
>>> +{
>>> + struct sdw_dma_dev_data *sdw_data;
>>> + struct acp_sdw_dma_stream *stream;
>>> + struct snd_pcm_runtime *runtime;
>>> + u32 period_bytes, buf_size, water_mark_size_reg;
>>> + int ret;
>>> + int index;
>>> +
>>> + sdw_data = dev_get_drvdata(dev);
>>> + for (index = 0; index < ACP63_SDW0_DMA_MAX_STREAMS; index++) {
>>> + if (sdw_data->sdw0_dma_stream[index] &&
>>> + sdw_data->sdw0_dma_stream[index]->runtime) {
>>> + water_mark_size_reg = sdw0_dma_ring_buf_reg[index].water_mark_size_reg;
>>> + runtime = sdw_data->sdw0_dma_stream[index]->runtime;
>>> + stream = runtime->private_data;
>>> + period_bytes = frames_to_bytes(runtime, runtime->period_size);
>>> + buf_size = frames_to_bytes(runtime, runtime->buffer_size);
>>> + acp63_config_dma(stream, sdw_data->acp_base, index);
>>> + ret = acp63_configure_sdw_ringbuffer(sdw_data->acp_base, index,
>>> + buf_size, ACP_SDW0);
>>> + if (ret)
>>> + return ret;
>>> + writel(period_bytes, sdw_data->acp_base + water_mark_size_reg);
>>> + }
>>> + }
>>> + for (index = 0; index < ACP63_SDW1_DMA_MAX_STREAMS; index++) {
>>> + if (sdw_data->sdw1_dma_stream[index] &&
>>> + sdw_data->sdw1_dma_stream[index]->runtime) {
>>> + water_mark_size_reg = sdw1_dma_ring_buf_reg[index].water_mark_size_reg;
>>> + runtime = sdw_data->sdw1_dma_stream[index]->runtime;
>>> + stream = runtime->private_data;
>>> + period_bytes = frames_to_bytes(runtime, runtime->period_size);
>>> + buf_size = frames_to_bytes(runtime, runtime->buffer_size);
>>> + acp63_config_dma(stream, sdw_data->acp_base, index);
>>> + ret = acp63_configure_sdw_ringbuffer(sdw_data->acp_base, index,
>>> + buf_size, ACP_SDW1);
>>> + if (ret)
>>> + return ret;
>>> + writel(period_bytes, sdw_data->acp_base + water_mark_size_reg);
>>> + }
>>> + }
>> Isn't this set of configurations something that needs to be done already
>> somewhere else, i.e. could there be a common helper?
> In hw_params() callback, we are setting period_bytes and buf_size from
> params structure. We are extracting same variables from runtime structures
> in resume() callback.
> We can implement a helper function to further simplify above logic
> instead of having two separate loops.

ok