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

jassi brar jassisinghbrar at gmail.com
Mon Sep 7 14:40:40 CEST 2009

On Mon, Sep 7, 2009 at 8:58 PM, Mark
Brown<broonie at opensource.wolfsonmicro.com> wrote:
> On Mon, Sep 07, 2009 at 11:35:08AM +0900, jassi brar wrote:
>> On Sun, Sep 6, 2009 at 10:42 PM, Mark
>> Brown<broonie at opensource.wolfsonmicro.com> wrote:
>> >>     Codec recommends  - BCLK={32, 48}   RFS={384}
>> > I'm not sure where these CODEC recommendations come from?
>> Well, my example was inspired from one recommendation/constraint i
>> found at Page-23, of WM8580A manual Rev-4.7 March-2009.
>> It indicates that we can't have BCLK as 16fs if RFS(MCLK/LRCLK) is
>> either 128fs or 192fs.
> That's not a recommendation, that's a hardware limit.
Another way of putting it.
When we can't do somthing, it is recommended otherwise :)

> Though I still
> don't see how we get to a 48fs BCLK (which could only be generated with
> a 48fs system clock) or a recommendation for a 384fs MCLK in particular.
> This is all a bit of a sidetrack anyway.
Yes, a badly put example.

>> Just as WM8580 has a constraint on BCLK(128fs) at MCLK=128,192fs, some
>> SoC may have a constraint of using BCLK=48fs for MCLK=384fs
>> @16-bits/sample.
> Like I say, I'd be very surprised to see any such constraint
This was just an example.
I once had to set non-obvious values of BCLK+MCLK on the codec due to the clock
I had that ran the SoC in Master mode. Will let you know the real life
example if i cud dig that up again.

I think i have made whatever points i had. Am at peace now :)
Do as u wish appropriate with the patch.


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