[PATCH] ASoC: codecs: wcd938x: fix codec initialisation race

[PATCH] ASoC: codecs: wcd938x: fix codec initialisation race

[Johan Hovold]

Make sure to resume the codec and soundwire device before trying to read
the codec variant and configure the device during component probe.

This specifically avoids interpreting (a masked and shifted) -EBUSY
errno as the variant:

	wcd938x_codec audio-codec: ASoC: error at soc_component_read_no_lock on audio-codec for register: [0x000034b0] -16

when the soundwire device happens to be suspended, which in turn
prevents some headphone controls from being registered.

Fixes: 8d78602aa87a ("ASoC: codecs: wcd938x: add basic driver")
Cc: stable@vger.kernel.org      # 5.14
Cc: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Reported-by: Steev Klimaszewski <steev@kali.org>
Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
---
 sound/soc/codecs/wcd938x.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/sound/soc/codecs/wcd938x.c b/sound/soc/codecs/wcd938x.c
index e7d6a02cdec0..e3ae4fb2c4db 100644
--- a/sound/soc/codecs/wcd938x.c
+++ b/sound/soc/codecs/wcd938x.c
@@ -3085,6 +3085,10 @@ static int wcd938x_soc_codec_probe(struct snd_soc_component *component)
 
 	snd_soc_component_init_regmap(component, wcd938x->regmap);
 
+	ret = pm_runtime_resume_and_get(dev);
+	if (ret < 0)
+		return ret;
+
 	wcd938x->variant = snd_soc_component_read_field(component,
 						 WCD938X_DIGITAL_EFUSE_REG_0,
 						 WCD938X_ID_MASK);
@@ -3098,6 +3102,8 @@ static int wcd938x_soc_codec_probe(struct snd_soc_component *component)
 			     (WCD938X_DIGITAL_INTR_LEVEL_0 + i), 0);
 	}
 
+	pm_runtime_put(dev);
+
 	wcd938x->hphr_pdm_wd_int = regmap_irq_get_virq(wcd938x->irq_chip,
 						       WCD938X_IRQ_HPHR_PDM_WD_INT);
 	wcd938x->hphl_pdm_wd_int = regmap_irq_get_virq(wcd938x->irq_chip,
-- 
2.39.3

Re: [PATCH] ASoC: codecs: wcd938x: fix codec initialisation race

[Mark Brown]

On Fri, 30 Jun 2023 14:03:18 +0200, Johan Hovold wrote:
> Make sure to resume the codec and soundwire device before trying to read
> the codec variant and configure the device during component probe.
> 
> This specifically avoids interpreting (a masked and shifted) -EBUSY
> errno as the variant:
> 
> 	wcd938x_codec audio-codec: ASoC: error at soc_component_read_no_lock on audio-codec for register: [0x000034b0] -16
> 
> [...]

Applied to

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

Thanks!

[1/1] ASoC: codecs: wcd938x: fix codec initialisation race
      commit: 85a61b1ce461a3f62f1019e5e6423c393c542bff

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