[alsa-devel] [PATCH 3/5] SOUND: SOC: CODECS: Add support for the TWL4030 audio codec
sakoman at gmail.com
Fri Sep 5 16:25:58 CEST 2008
On Fri, Sep 5, 2008 at 3:30 AM, Mark Brown <broonie at sirena.org.uk> wrote:
> On Thu, Sep 04, 2008 at 07:32:28AM -0700, Steve Sakoman wrote:
>> On Thu, Sep 4, 2008 at 3:26 AM, Jarkko Nikula <jarkko.nikula at nokia.com> wrote:
>> I could probably get rid of this function. It was quite useful during
>> debugging and I was not aware of codec_reg_show. IIRC, most of the
>> other codec drivers also have the equivalent of this function, so we
>> might want to clean them up too if there is a standard function to
>> replace them.
> Any references? None of the in-tree drivers have them...
Heh, you are correct.
I could swear I did a cut'n'paste on the reg cache stuff including the
dump. Perhaps just old timers disease . . .
>> It *seems* to work without them, but every historic TI driver seemed
>> to have them. I figured that they might know something not reflected
>> in the documentation. I will add a REVIST comment.
> This sort of stuff is very common in codec drivers - normally the delays
> are there to allow the analogue side of the system time to settle down
> (waiting for capacitors to charge/discharge or reference voltages to
> stabalise, for example). Ideally they have comments saying what's going
> on, of course. Missing these delays often won't actually stop things
> working completely but will instead do things like reduce performance or
> generate audio artefacts - and sometimes it's application dependant if
> these are important.
That was my assumption too, so I left them under the "better safe than
As suggested, I moved all sets and clears of CODEXPDZ to function
calls which include the delay.
Thanks again for the comments.
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