[alsa-devel] [PATCH] Minor WM8580 enhancements.

jassi brar jassisinghbrar at gmail.com
Sun Sep 6 03:50:26 CEST 2009

On Sun, Sep 6, 2009 at 10:22 AM, Mark
Brown<broonie at opensource.wolfsonmicro.com> wrote:
> On Sun, Sep 06, 2009 at 09:09:41AM +0900, jassi brar wrote:
>> +     case WM8580_MCLKRATIO:
>> +     case WM8580_BCLKRATIO:
> There should be no need for machine drivers to configure any of this,
> there's already enough information in the CODEC driver to figure out
> this configuration without their help.
Not all combinations of BFS and RFS are possible at all LRCLK values
for CPU_DAI, not for Samsung SoCs those I am aware of.
So, i think the machine driver, as a link between Codec and Cpu Dai, has the
job of figuring out values for BFS and RFS that are compatible to
_both_ the CPU and the CODEC.
If CODEC driver, with disregard to the CPU, chooses values for
BCLK/MCLK-Ratio that are incompatible
with CPU, i don't know how that will work out.
Please correct, if i am missing something.

> As mentioned previously this driver could use a bit of modernisation in
> general, including with regard to clocking, which I had already been
> planning to do as part of working on the SMDK boards.  As a result of
> some work on another chip with a very similar clocking structure I have
> a rough draft of what needs doing for the clocks already.  This is part
> of why in my earlier mail I had recommended focusing on the CPU DAI
> drivers for now - the lack of them is the biggest obstacle to getting
> that work cleaned up and tested.
I get your recommendation, but i am already in the middle of
submitting I2S machine
driver for 6410-WM8580 mainline and that is one of the tasks i am assigned.
Ofcourse, after 6410-wm8580 driver is all up and available to our
users, i can switch to AC97.

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