[alsa-devel] [PATCH 1/3] ASoC: Intel: sof_pcm512x: add support for SOF platforms with pcm512x

[Pierre-Louis Bossart]

On 1/30/20 9:17 AM, Mark Brown wrote:
> On Thu, Jan 30, 2020 at 09:14:29AM -0600, Pierre-Louis Bossart wrote:
> 
>>> These look like they might be a DAPM widget of some kind?
> 
>> it's the LED support only, turned on when you play and off when you stop.
>> At some point, I added a gpiochip support in the PCM152x codec driver to
>> avoid doing this, and have a nicer way of toggling the gpios. Due to lack of
>> time, I didn't maintain this solution, but we could add it in a follow-up
>> version if that was desired. It's really not the main functionality of this
>> patch.
> 
> Followup seems fine.

ok, will work on it, I haven't changed the code since December 2018
https://github.com/plbossart/sound/commits/hifiberry/gpios

Another thing I didn't complete is the support for the codec master 
mode, which would be needed for the Hifiberry DAC+ PRO versions (they 
have 2 oscillators for 44.1 and 48kHz support). It's a bit of a 
chicken-and-egg, during the probe the codec driver requests an mclk but 
in the case of the hifiberry the mclk is actually enabled at the codec 
level with a GPIO selection. I never found a clean way to do this, or an 
example where the clock consumer is also the clock provider. So far we 
only use these PRO boards in codec slave mode, which is a bit of a 
waste. For once we have good clocks, we should really use them...