[alsa-devel] [PATCH] Add support for CLKOUT to wm8731 codec driver

Mark Brown broonie at opensource.wolfsonmicro.com
Fri Oct 30 19:32:07 CET 2009

On 30 Oct 2009, at 18:22, Bill Gatliff <bgat at billgatliff.com> wrote:

> Mark Brown wrote:
>> On Fri, Oct 30, 2009 at 11:50:20AM -0500, Bill Gatliff wrote:
>>> Mark Brown wrote:
>>>> It'd be better define a new clock for the CLKOUT pin rather than  
>>>> munging
>>>> it in with the master clock.  MCLK is always an input on the  
>>>> WM8731, the
>>>> CLKOUT output is a separate pin and so including it in MCLK is  
>>>> likely to
>>>> make things confusing and could well introduce errors.
>>> Could you explain more about what you meant by this?  I'm trying to
>>> rework these patches now, and I don't understand how to implement  
>>> what
>>> you are suggesting.
>> Define two clock IDs and then use a switch statement in the  
>> function to
>> determine which to act on, allowing the master clock to be controlled
>> separately to the output clock.
> Can you refer me to an existing example?

wm8993 supports multiple internal options for sysclk usig the id  
parameter. Could you be more explicit about what you can't follow here  
please? I might be able to help more if I could see what's confusing  

> b.g.
> -- 
> Bill Gatliff
> bgat at billgatliff.com

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