[PATCH] ASoC: mediatek: mt8188-mt6359: Remove hardcoded dmic codec

[Chen-Yu Tsai]

Hi,

On Wed, Dec 4, 2024 at 3:22 AM Nícolas F. R. A. Prado
<nfraprado at collabora.com> wrote:
>
> Remove hardcoded dmic codec from the UL_SRC dai link to avoid requiring
> a dmic codec to be present for the driver to probe, as not every
> MT8188-based platform might need a dmic codec. The codec can be assigned
> to the dai link through the dai-link property in Devicetree on the
> platforms where it is needed.

A followup question about this. The DMICs on the Chromebooks are attached
to the PMIC codec's input side, which then converts the signals to standard
I2S and passes them out to the SoC through its AIF1. So the original code
was somewhat incorrect, though it works.

How should we describe such a connection, given that the MediaTek sound
bindings aren't a full graph?

> No Devicetree currently relies on it so it is safe to remove without
> worrying about backward compatibility.

Removing it didn't seem to cause any issues for the Chromebooks that
do actually have DMICs. I suspect the only difference would be that
the wakeup-delays no longer apply correctly.


Thanks
ChenYu

> Fixes: 9f08dcbddeb3 ("ASoC: mediatek: mt8188-mt6359: support new board with nau88255")
> Signed-off-by: Nícolas F. R. A. Prado <nfraprado at collabora.com>
> ---
>  sound/soc/mediatek/mt8188/mt8188-mt6359.c | 4 +---
>  1 file changed, 1 insertion(+), 3 deletions(-)
>
> diff --git a/sound/soc/mediatek/mt8188/mt8188-mt6359.c b/sound/soc/mediatek/mt8188/mt8188-mt6359.c
> index 08ae962afeb92965109b303439419bc6e7c2a896..1550e56ab57d54b179ebe5cbd60db1660bb0bd2c 100644
> --- a/sound/soc/mediatek/mt8188/mt8188-mt6359.c
> +++ b/sound/soc/mediatek/mt8188/mt8188-mt6359.c
> @@ -188,9 +188,7 @@ SND_SOC_DAILINK_DEFS(pcm1,
>  SND_SOC_DAILINK_DEFS(ul_src,
>                      DAILINK_COMP_ARRAY(COMP_CPU("UL_SRC")),
>                      DAILINK_COMP_ARRAY(COMP_CODEC("mt6359-sound",
> -                                                  "mt6359-snd-codec-aif1"),
> -                                       COMP_CODEC("dmic-codec",
> -                                                  "dmic-hifi")),
> +                                                  "mt6359-snd-codec-aif1")),
>                      DAILINK_COMP_ARRAY(COMP_EMPTY()));
>
>  SND_SOC_DAILINK_DEFS(AFE_SOF_DL2,
>
> ---
> base-commit: b852e1e7a0389ed6168ef1d38eb0bad71a6b11e8
> change-id: 20241203-mt8188-6359-unhardcode-dmic-ba7649f8a72b
>
> Best regards,
> --
> Nícolas F. R. A. Prado <nfraprado at collabora.com>
>
>