Re: [PATCH] ASoC: codecs: wsa884x: Add mute control knob

From: Sebastian Reichel

Date: Sat Oct 17 2026 - 15:42:09 EST


Hello Mark,

On Thu, Oct 15, 2026 at 06:54:52PM +0100, Mark Brown wrote:
> On Wed, Oct 14, 2026 at 07:02:54PM +0200, Sebastian Reichel wrote:
> > This codec is typically used with ALSA UCM, which right now falls back
> > to handling mute in software. Expose proper hardware mute control
> > considering the driver already handles it internally anyways, which
> > allows UCM to bind speaker mute LED to the new control knob.
>
> The reason we have the mute control in stream startup is to mask
> glitches caused by the hardware during startup, for example clocking
> random things out of FIFOs. Are we sure that this isn't an issue?

I guessed that part. My change should leave it working as the
user requested mute is OR'd in. So during stream startup with the
user mute control 'unmuted' nothing should change. With the user
mute control in 'mute' state it will stay muted during stream
startup (so no glitch possible IIUIC).

The only potential issue I see is toggling the user control while
the stream is already running. I don't have documentation for this
chip, but I'm running a kernel with this patch on my T14s Gen6
Snapdragon for a few days now and didn't notice any issues.

Greetings,

-- Sebastian

Attachment: signature.asc
Description: PGP signature