[PATCH] ASoC: stm32: sai: add pm_runtime support

[PATCH] ASoC: stm32: sai: add pm_runtime support

[Olivier Moysan]

Enable support of pm_runtime on STM32 SAI driver to allow
SAI power state monitoring.
pm_runtime_put_autosuspend() is called from ASoC framework
on pcm device close.
The pmdown_time delay is available in runtime context, and may be set
in SAI driver to take into account shutdown delay on playback.
However, this shutdown delay is already handled in the DAPMs
of the audio codec linked to SAI CPU DAI.
So, the choice is made, not to support this delay on CPU DAI side.

Signed-off-by: Olivier Moysan <olivier.moysan@st.com>
---
 sound/soc/stm/stm32_sai_sub.c | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/sound/soc/stm/stm32_sai_sub.c b/sound/soc/stm/stm32_sai_sub.c
index 3fb9513cedb2..3aa1cf262402 100644
--- a/sound/soc/stm/stm32_sai_sub.c
+++ b/sound/soc/stm/stm32_sai_sub.c
@@ -12,6 +12,7 @@
 #include <linux/module.h>
 #include <linux/of_irq.h>
 #include <linux/of_platform.h>
+#include <linux/pm_runtime.h>
 #include <linux/regmap.h>
 
 #include <sound/asoundef.h>
@@ -1559,10 +1560,14 @@ static int stm32_sai_sub_probe(struct platform_device *pdev)
 
 	ret = snd_soc_register_component(&pdev->dev, &stm32_component,
 					 &sai->cpu_dai_drv, 1);
-	if (ret)
+	if (ret) {
 		snd_dmaengine_pcm_unregister(&pdev->dev);
+		return ret;
+	}
 
-	return ret;
+	pm_runtime_enable(&pdev->dev);
+
+	return 0;
 }
 
 static int stm32_sai_sub_remove(struct platform_device *pdev)
@@ -1572,6 +1577,7 @@ static int stm32_sai_sub_remove(struct platform_device *pdev)
 	clk_unprepare(sai->pdata->pclk);
 	snd_dmaengine_pcm_unregister(&pdev->dev);
 	snd_soc_unregister_component(&pdev->dev);
+	pm_runtime_disable(&pdev->dev);
 
 	return 0;
 }
-- 
2.17.1

Re: [PATCH] ASoC: stm32: sai: add pm_runtime support

[Mark Brown]

On Fri, 11 Sep 2020 10:15:07 +0200, Olivier Moysan wrote:
> Enable support of pm_runtime on STM32 SAI driver to allow
> SAI power state monitoring.
> pm_runtime_put_autosuspend() is called from ASoC framework
> on pcm device close.
> The pmdown_time delay is available in runtime context, and may be set
> in SAI driver to take into account shutdown delay on playback.
> However, this shutdown delay is already handled in the DAPMs
> of the audio codec linked to SAI CPU DAI.
> So, the choice is made, not to support this delay on CPU DAI side.

Applied to

   https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound.git for-next

Thanks!

[1/1] ASoC: stm32: sai: add pm_runtime support
      commit: 4e723e7565c4031568fb9db18253cfbf6442831d

All being well this means that it will be integrated into the linux-next
tree (usually sometime in the next 24 hours) and sent to Linus during
the next merge window (or sooner if it is a bug fix), however if
problems are discovered then the patch may be dropped or reverted.

You may get further e-mails resulting from automated or manual testing
and review of the tree, please engage with people reporting problems and
send followup patches addressing any issues that are reported if needed.

If any updates are required or you are submitting further changes they
should be sent as incremental updates against current git, existing
patches will not be replaced.

Please add any relevant lists and maintainers to the CCs when replying
to this mail.

Thanks,
Mark