[alsa-devel] [PATCH 0/2] ASoC: mediatek: mt8183-da7219: add separate speaker switch

[Tzung-Bi Shih]

Per previous discussion[1], the patch moves control of SD_MODE from
PCM trigger to DAPM (i.e. set SD_MODE earilier if playback).

Possible drawback: may generate pop noise when BCLK=on but LRCLK=off.
As the datasheet[2] mentioned:
> Do not remove LRCLK while BCLK is present.
> Removing LRCLK while BCLK is present can cause unexpected output behavior
> including a large DC output voltage.

That is also the original purpose of sdmode-delay: to make sure SD_MODE
is the last one to be set.

[1]: https://patchwork.kernel.org/patch/11363953/
[2]: https://datasheets.maximintegrated.com/en/ds/MAX98357A-MAX98357B.pdf

Tzung-Bi Shih (2):
  ASoC: max98357a: move control of SD_MODE to DAPM
  ASoC: mediatek: mt8183-da7219: add speaker switch

 sound/soc/codecs/max98357a.c                  | 36 +++++++++----------
 .../mediatek/mt8183/mt8183-da7219-max98357.c  | 19 ++++++++++
 2 files changed, 36 insertions(+), 19 deletions(-)

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2.25.0.225.g125e21ebc7-goog