Re: [PATCH] ASoC: max98373: Added 10ms delay after amp software reset

From: Dmitry Torokhov
Date: Wed Aug 22 2018 - 20:31:21 EST


On Wed, Aug 22, 2018 at 5:21 PM Ryan Lee <ryans.lee@xxxxxxxxxxxxxxxxxxx> wrote:
>
> Signed-off-by: Ryan Lee <ryans.lee@xxxxxxxxxxxxxxxxxxx>
> ---
> Changes : Applied 10ms delay after amp software reset.
> 10ms guard time is required for stability.
> sound/soc/codecs/max98373.c | 2 ++
> 1 file changed, 2 insertions(+)
>
> diff --git a/sound/soc/codecs/max98373.c b/sound/soc/codecs/max98373.c
> index 2764fae..6aaff03 100644
> --- a/sound/soc/codecs/max98373.c
> +++ b/sound/soc/codecs/max98373.c
> @@ -730,6 +730,7 @@ static int max98373_probe(struct snd_soc_component *component)
> /* Software Reset */
> regmap_write(max98373->regmap,
> MAX98373_R2000_SW_RESET, MAX98373_SOFT_RESET);
> + mdelay(10);

Is it really necessary for the CPU to spin for 10msec here?
usleep_range() would be better solution.

>
> /* IV default slot configuration */
> regmap_write(max98373->regmap,
> @@ -818,6 +819,7 @@ static int max98373_resume(struct device *dev)
>
> regmap_write(max98373->regmap,
> MAX98373_R2000_SW_RESET, MAX98373_SOFT_RESET);
> + mdelay(10);
> regcache_cache_only(max98373->regmap, false);
> regcache_sync(max98373->regmap);
> return 0;
> --
> 2.7.4
>

Thanks.

--
Dmitry