[alsa-devel] [PATCH] HDA: add powersaving hook for Realtek

[Takashi Iwai]

At Sun, 20 Dec 2009 23:00:57 +0100,
Hector Martin wrote:
> 
> Missed a coupld #ifdefs, resending.
> 
> The current Realtek code makes no specific provision for turning stuff
> off. The codec chip is placed into low-power mode generically, but this
> doesn't turn off any external hardware connected to it, in particular
> external amplifiers.
> 
> This patch creates a hook function that is called by the codec
> suspend/resume functions. It ought to disable any external hardware in a
> device-specific way. I've implemented a generic ALC889 function that
> sets the EAPD pin properly, and used it for the Acer Aspire 8930G which
> can benefit from this feature.
> 
> On my laptop, this results in ~0.5W extra savings.

This is nice.  Maybe we should a bit more generalized also for other
machines.

But now applied as is for the next pull request.  Thanks.


Takashi