Re: [PATCH 5/8] ASoC: SOF: ipc4: Add support for Intel HW managed mic privacy messaging

[Péter Ujfalusi <peter.ujfalusi@xxxxxxxxxxxxxxx>]

On 06/03/2025 15:42, Mark Brown wrote:
> On Thu, Mar 06, 2025 at 03:35:24PM +0200, Peter Ujfalusi wrote:
> 
>> Platform code can call sof_ipc4_mic_privacy_state_change() to send the IPC
>> message to the firmware on state change.
> 
> What's the plan for that plaform code - is it expected to be the machine
> driver, or something else?

By platform code I mean here sound/soc/sof/intel.

This feature is only available for Intel hardware, but I wanted to keep
the APIs as open as possible for other vendors.

The reason for the implementation is that the interrupt about the change
in mic privacy is delivered via IP interrupt (piggy-backing on them).
The interrupt is delivered to the owner of the IP:
DMIC is owned by DSP, so firmware can handle it
SNDW is owned by host, so Linux is handling it.
The firmware needs to be notified of a change to do a nice fade out/in,
the software cannot block or do anything else, the incoming stream mute
is done by the hardware.

No plan to integrate it to machine drivers, this is outside of the scope
of SW. The feedback is also handled by hardware internally.

-- 
Péter