This patch suggests enabling pm_runtime during the probe, but marking the
device as 'active' only after it is enumerated. That will force a
dependency between the card and the codec, pm_runtime_get_sync() will
have to wait for the codec device to resume and hence implicitly wait
for the enumeration/initialization to be completed. In the nominal
case where the codec device is already active the get_sync() would
only perform a ref-count increase.
The changes are directly inspired by RT711 and RT711-sdca changes.
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@xxxxxxxxxxxxxxx>
Reviewed-by: Ranjani Sridharan <ranjani.sridharan@xxxxxxxxxxxxxxx>
Reviewed-by: Rander Wang <rander.wang@xxxxxxxxx>
Reviewed-by: Bard Liao <yung-chuan.liao@xxxxxxxxxxxxxxx>
---
sound/soc/codecs/max98373-sdw.c | 40 ++++++++++++++++++---------------
1 file changed, 22 insertions(+), 18 deletions(-)
diff --git a/sound/soc/codecs/max98373-sdw.c b/sound/soc/codecs/max98373-sdw.c
index 92d2b872f9f8..b5cb951af570 100644
--- a/sound/soc/codecs/max98373-sdw.c
+++ b/sound/soc/codecs/max98373-sdw.c
@@ -366,22 +366,12 @@ static int max98373_io_init(struct sdw_slave *slave)
regcache_cache_bypass(max98373->regmap, true);
/*
- * PM runtime is only enabled when a Slave reports as Attached
+ * PM runtime status is marked as 'active' only when a Slave reports as Attached
*/
- if (!max98373->first_hw_init) {
- /* set autosuspend parameters */
- pm_runtime_set_autosuspend_delay(dev, 3000);
- pm_runtime_use_autosuspend(dev);
-
+ if (!max98373->first_hw_init)
/* update count of parent 'active' children */
pm_runtime_set_active(dev);
- /* make sure the device does not suspend immediately */
- pm_runtime_mark_last_busy(dev);
-
- pm_runtime_enable(dev);
- }
-
pm_runtime_get_noresume(dev);
/* Software Reset */
@@ -774,10 +764,27 @@ static int max98373_init(struct sdw_slave *slave, struct regmap *regmap)
ret = devm_snd_soc_register_component(dev, &soc_codec_dev_max98373_sdw,
max98373_sdw_dai,
ARRAY_SIZE(max98373_sdw_dai));
- if (ret < 0)
+ if (ret < 0) {
dev_err(dev, "Failed to register codec: %d\n", ret);
+ return ret;
+ }
- return ret;
+ /* set autosuspend parameters */
+ pm_runtime_set_autosuspend_delay(dev, 3000);
+ pm_runtime_use_autosuspend(dev);
+
+ /* make sure the device does not suspend immediately */
+ pm_runtime_mark_last_busy(dev);
+
+ pm_runtime_enable(dev);
+
+ /* important note: the device is NOT tagged as 'active' and will remain
+ * 'suspended' until the hardware is enumerated/initialized. This is required
+ * to make sure the ASoC framework use of pm_runtime_get_sync() does not silently
+ * fail with -EACCESS because of race conditions between card creation and enumeration
+ */
+
+ return 0;
}
static int max98373_update_status(struct sdw_slave *slave,
@@ -835,10 +842,7 @@ static int max98373_sdw_probe(struct sdw_slave *slave,
static int max98373_sdw_remove(struct sdw_slave *slave)
{
- struct max98373_priv *max98373 = dev_get_drvdata(&slave->dev);
-
- if (max98373->first_hw_init)
- pm_runtime_disable(&slave->dev);
+ pm_runtime_disable(&slave->dev);
return 0;
}
--
2.39.2
