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

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

[Johan Hovold]

Make sure that the soundwire device used for register accesses has been
enumerated and initialised before trying to read the codec variant
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

in case the soundwire device has not yet been initialised, 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 | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/sound/soc/codecs/wcd938x.c b/sound/soc/codecs/wcd938x.c
index e3ae4fb2c4db..4571588fad62 100644
--- a/sound/soc/codecs/wcd938x.c
+++ b/sound/soc/codecs/wcd938x.c
@@ -3080,9 +3080,18 @@ static int wcd938x_irq_init(struct wcd938x_priv *wcd, struct device *dev)
 static int wcd938x_soc_codec_probe(struct snd_soc_component *component)
 {
 	struct wcd938x_priv *wcd938x = snd_soc_component_get_drvdata(component);
+	struct sdw_slave *tx_sdw_dev = wcd938x->tx_sdw_dev;
 	struct device *dev = component->dev;
+	unsigned long time_left;
 	int ret, i;
 
+	time_left = wait_for_completion_timeout(&tx_sdw_dev->initialization_complete,
+						msecs_to_jiffies(2000));
+	if (!time_left) {
+		dev_err(dev, "soundwire device init timeout\n");
+		return -ETIMEDOUT;
+	}
+
 	snd_soc_component_init_regmap(component, wcd938x->regmap);
 
 	ret = pm_runtime_resume_and_get(dev);
-- 
2.39.3

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

[Steev Klimaszewski]

On Sat, Jul 1, 2023 at 4:48 AM Johan Hovold <johan+linaro@kernel.org> wrote:
>
> Make sure that the soundwire device used for register accesses has been
> enumerated and initialised before trying to read the codec variant
> 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
>
> in case the soundwire device has not yet been initialised, 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 | 9 +++++++++
>  1 file changed, 9 insertions(+)
>
> diff --git a/sound/soc/codecs/wcd938x.c b/sound/soc/codecs/wcd938x.c
> index e3ae4fb2c4db..4571588fad62 100644
> --- a/sound/soc/codecs/wcd938x.c
> +++ b/sound/soc/codecs/wcd938x.c
> @@ -3080,9 +3080,18 @@ static int wcd938x_irq_init(struct wcd938x_priv *wcd, struct device *dev)
>  static int wcd938x_soc_codec_probe(struct snd_soc_component *component)
>  {
>         struct wcd938x_priv *wcd938x = snd_soc_component_get_drvdata(component);
> +       struct sdw_slave *tx_sdw_dev = wcd938x->tx_sdw_dev;
>         struct device *dev = component->dev;
> +       unsigned long time_left;
>         int ret, i;
>
> +       time_left = wait_for_completion_timeout(&tx_sdw_dev->initialization_complete,
> +                                               msecs_to_jiffies(2000));
> +       if (!time_left) {
> +               dev_err(dev, "soundwire device init timeout\n");
> +               return -ETIMEDOUT;
> +       }
> +
>         snd_soc_component_init_regmap(component, wcd938x->regmap);
>
>         ret = pm_runtime_resume_and_get(dev);
> --
> 2.39.3
>

Thank you!  Tested with this and the other patch applied on my X13s
with a pair of Apple EarPods with 3.5mm Headphone Plug, audio is quite
nice through them.

Tested-by: Steev Klimaszewski <steev@kali.org>

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

[Mark Brown]

On Sat, 01 Jul 2023 11:47:23 +0200, Johan Hovold wrote:
> Make sure that the soundwire device used for register accesses has been
> enumerated and initialised before trying to read the codec variant
> during component probe.
> 
> This specifically avoids interpreting (a masked and shifted) -EBUSY
> errno as the variant:
> 
> [...]

Applied to

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

Thanks!

[1/1] ASoC: codecs: wcd938x: fix soundwire initialisation race
      commit: 6f49256897083848ce9a59651f6b53fc80462397

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