[PATCH v2 3/4] ASoC: cs35l41: Hibernate wm_adsp on runtime suspend

[Stefan Binding]

When the CS35L41 driver suspends, it is put into hibernation, and
the regmap goes into cache_only, but the firmware is still running, and
wm_adsp is not stopped. If userspace attempts to read a firmware
control, it will perform a regmap_raw_read() and this will produce an
error in the kernel log. To prevent spurious errors, put the DSP into
hibernation which prevents access to the hardware for the ALSA
controls.

Signed-off-by: Stefan Binding <sbinding@xxxxxxxxxxxxxxxxxxxxx>
---
 sound/soc/codecs/cs35l41.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/sound/soc/codecs/cs35l41.c b/sound/soc/codecs/cs35l41.c
index ee56dfceedeb..b2a076706c79 100644
--- a/sound/soc/codecs/cs35l41.c
+++ b/sound/soc/codecs/cs35l41.c
@@ -1404,6 +1404,7 @@ static int cs35l41_runtime_suspend(struct device *dev)
 	if (!cs35l41->dsp.preloaded || !cs35l41->dsp.cs_dsp.running)
 		return 0;
 
+	wm_adsp_hibernate(&cs35l41->dsp, true);
 	cs35l41_enter_hibernate(dev, cs35l41->regmap, cs35l41->hw_cfg.bst_type);
 
 	regcache_cache_only(cs35l41->regmap, true);
@@ -1432,10 +1433,14 @@ static int cs35l41_runtime_resume(struct device *dev)
 	cs35l41_test_key_unlock(cs35l41->dev, cs35l41->regmap);
 	ret = regcache_sync(cs35l41->regmap);
 	cs35l41_test_key_lock(cs35l41->dev, cs35l41->regmap);
+
+	wm_adsp_hibernate(&cs35l41->dsp, false);
+
 	if (ret) {
 		dev_err(cs35l41->dev, "Failed to restore register cache: %d\n", ret);
 		return ret;
 	}
+
 	cs35l41_init_boost(cs35l41->dev, cs35l41->regmap, &cs35l41->hw_cfg);
 
 	return 0;
-- 
2.43.0