[alsa-devel] simplest volume control possible

Mark Brown broonie at sirena.org.uk
Fri Nov 28 17:45:12 CET 2008

On 28 Nov 2008, at 14:50, "John Kacur" <jkacur at gmail.com> wrote:

> don't care about power, the thing can be powered on all the time. I
> put a one pulse on a gpio for volume up and a zero pulse on a gpio for
> volume down, 0 - 63 pulses though.
> Question, then, what would be an appropriate widget to use?

You don't need to implement DAPM if you don't want/need to. It'd be  
helpful to define noop controls for the DAC and output pins like the  
current TWL4030 driver does but it's not essential.

For your volume control you'll need to write a custom control - all  
the standard ASoC stuff is for chips with registers.

More information about the Alsa-devel mailing list