[RFC PATCH 39/40] soundwire: intel: add pm_runtime support

From: Pierre-Louis Bossart
Date: Thu Jul 25 2019 - 19:42:06 EST


Add basic hooks in DAI .startup and .shutdown callbacks. The SoundWire
IP should be powered between those two calls.

By default the platform_device is in SUSPENDED mode, it is required to
call pm_runtime_set_active() before _enable()

FIXME: do we need to use mark_last_busy()?

Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@xxxxxxxxxxxxxxx>
---
drivers/soundwire/intel.c | 38 ++++++++++++++++++++++++++++++++++++++
1 file changed, 38 insertions(+)

diff --git a/drivers/soundwire/intel.c b/drivers/soundwire/intel.c
index db7bf2912767..1394a2322553 100644
--- a/drivers/soundwire/intel.c
+++ b/drivers/soundwire/intel.c
@@ -707,6 +707,23 @@ static void intel_port_cleanup(struct sdw_cdns_dma_data *dma)
}
}

+static int intel_startup(struct snd_pcm_substream *substream,
+ struct snd_soc_dai *dai)
+{
+ struct sdw_cdns *cdns = snd_soc_dai_get_drvdata(dai);
+ int ret;
+
+ ret = pm_runtime_get_sync(cdns->dev);
+ if (ret < 0) {
+ dev_err_ratelimited(cdns->dev,
+ "pm_runtime_get_sync failed in %s, ret %d\n",
+ __func__, ret);
+ pm_runtime_put_noidle(cdns->dev);
+ }
+
+ return ret;
+}
+
static int intel_hw_params(struct snd_pcm_substream *substream,
struct snd_pcm_hw_params *params,
struct snd_soc_dai *dai)
@@ -829,6 +846,8 @@ void intel_shutdown(struct snd_pcm_substream *substream,
struct snd_soc_dai *dai)
{
struct sdw_cdns_dma_data *dma;
+ struct sdw_cdns *cdns = snd_soc_dai_get_drvdata(dai);
+ int ret;

dma = snd_soc_dai_get_dma_data(dai, substream);
if (!dma)
@@ -836,6 +855,13 @@ void intel_shutdown(struct snd_pcm_substream *substream,

snd_soc_dai_set_dma_data(dai, substream, NULL);
kfree(dma);
+
+ pm_runtime_mark_last_busy(cdns->dev);
+ ret = pm_runtime_put_autosuspend(cdns->dev);
+ if (ret < 0)
+ dev_err_ratelimited(cdns->dev,
+ "pM_runtime_put_autosuspend failed in %s:, ret %d\n",
+ __func__, ret);
}

static int intel_pcm_set_sdw_stream(struct snd_soc_dai *dai,
@@ -851,6 +877,7 @@ static int intel_pdm_set_sdw_stream(struct snd_soc_dai *dai,
}

static const struct snd_soc_dai_ops intel_pcm_dai_ops = {
+ .startup = intel_startup,
.hw_params = intel_hw_params,
.hw_free = intel_hw_free,
.shutdown = intel_shutdown,
@@ -1124,6 +1151,15 @@ static int intel_probe(struct platform_device *pdev)

intel_debugfs_init(sdw);

+ /* Enable PM */
+ pm_runtime_set_autosuspend_delay(&pdev->dev, 3000);
+ pm_runtime_use_autosuspend(&pdev->dev);
+
+ pm_runtime_mark_last_busy(&pdev->dev); /* FIXME: needed? */
+
+ pm_runtime_set_active(&pdev->dev);
+ pm_runtime_enable(&pdev->dev);
+
return 0;

err_dai:
@@ -1141,6 +1177,7 @@ static int intel_remove(struct platform_device *pdev)
sdw = platform_get_drvdata(pdev);

if (!sdw->cdns.bus.prop.hw_disabled) {
+ pm_runtime_disable(&pdev->dev);
intel_debugfs_exit(sdw);
free_irq(sdw->res->irq, sdw);
snd_soc_unregister_component(sdw->cdns.dev);
@@ -1212,6 +1249,7 @@ static int intel_resume(struct device *dev)

static const struct dev_pm_ops intel_pm = {
SET_SYSTEM_SLEEP_PM_OPS(intel_suspend, intel_resume)
+ SET_RUNTIME_PM_OPS(intel_suspend, intel_resume, NULL)
};

static struct platform_driver sdw_intel_drv = {
--
2.20.1