snd-rn-pci-acp3x - auto dmic detection unreliable

[Mukunda, Vijendar]

[AMD Public Use]



-----Original Message-----
From: Jaroslav Kysela <perex at perex.cz> 
Sent: Wednesday, November 18, 2020 2:37 PM
To: Mukunda, Vijendar <Vijendar.Mukunda at amd.com>
Cc: ALSA development <alsa-devel at alsa-project.org>
Subject: snd-rn-pci-acp3x - auto dmic detection unreliable

Hi,

	it seems that the ACPI auto-detection of the presence the digital microphone connected to AMD Renoir audio bridge is unreliable. It may be that hardware vendors do not provide the correct ACPI tables.
	Could you clarify the usage of _WOV integer value? It seems that this value is set on those plaforms which do not have the digital microphone (the microphone is connected to the HDA codec):

_WOV integer value should be set only when DMIC is connected to APU.
When DMIC is not available, _WOV integer value should be set to zero by BIOS.

Lenovo IdeaPad 5 (15ARE05)
Lenovo Thinkpad X395

	In any case, we should probably improve the auto-detection using DMI or other platform info.

					Jaroslav

BugLink: https://nam11.safelinks.protection.outlook.com/?url=https%3A%2F%2Fbugzilla.redhat.com%2Fshow_bug.cgi%3Fid%3D1892115&data=04%7C01%7CVijendar.Mukunda%40amd.com%7C4d901531b6454bebc58208d88ba15a4b%7C3dd8961fe4884e608e11a82d994e183d%7C0%7C0%7C637412872412887848%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000&sdata=S7769uYGT3db%2BaztzZyobmVN2leseXPqjR6pktFUaR0%3D&reserved=0

--
Jaroslav Kysela <perex at perex.cz>
Linux Sound Maintainer; ALSA Project; Red Hat, Inc.