[alsa-devel] 100.0% power usage of Device Audio codec (HDA) on wake

[David Henningsson]

On 11/20/2012 09:32 AM, Takashi Iwai wrote:
> At Tue, 20 Nov 2012 09:07:21 +0100,
> David Henningsson wrote:
>>
>> It does put another question - from where does powertop get its values,
>> and do we have to do anything on our side to make sure / aid them being
>> correct?
>
> powertop checks /sys/class/sound/hwC*D*/power_{off|on}_acct files.
> They contain the time (in ms) how long the codec is in the power-save
> mode.

Thanks. But I have also recently seen a computer where powertop showed a 
Watt number, essentially saying that the codec consumed 1.4 Watts or so 
(I don't remember the exact number). Have you seen that too?


-- 
David Henningsson, Canonical Ltd.
https://launchpad.net/~diwic