[alsa-devel] [RFC] ALSA: hda - check for mute/micmute LEDs on all Lenovo machines (Realtek)

David Henningsson david.henningsson at canonical.com
Thu Nov 7 09:34:14 CET 2013

On 11/07/2013 02:58 AM, Alex Hung wrote:
> @Takashi and David,
> DMI is a good way to check models, and we may not need to check the
> years as older Thinkpads with no mute led do not have "MMTS" and
> "SSMS" control methods in ACPI DSDT. Checking their existence before
> making the actual calls in thinkpad-acpi avoids this problems.

So, the only thing we want to avoid is to load the module if it should
not be loaded, and the symbol_request call will always load the module.
So we want to avoid calling symbol_request if it's not a hardware that
is supported by thinkpad-acpi (and I assume that means Ideapads).

Should we check the DMI information to distinguish between Thinkpads and
Ideapads (and potentially others), and what DMI string would be best to
look for?

David Henningsson, Canonical Ltd.

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