[alsa-devel] [PATCH] asoc, codec: Add SGTL5000 codec support to asoc
broonie at opensource.wolfsonmicro.com
Thu Dec 9 13:15:14 CET 2010
On Thu, Dec 09, 2010 at 03:22:35AM +0800, Zeng Zhaoming wrote:
> On Wed 2010-12-08 05:11:55, Mark Brown wrote:
> > On Wed, Dec 08, 2010 at 10:06:29AM +0800, zhaoming.zeng at freescale.com
> > > + sgtl5000_set_bias_level(codec, codec->suspend_bias_level);
> > The CODEC will never be in any state above STANDBY at suspend.
> Is there any documentation describe the state machine?
Not outside the source code.
> > > + msleep(1);
> > This delay looks like it's in the wrong place?
> The SGTL5000 has an internal reset that is deasserted 8 SYS_MCLK cycles after
> all power rails have been brought up. After this time communication can start.
> So I think delay 1ms is safe for the next operations.
It needs to be tied much more clearly to the enables, then - that's not
clear at the minute, especially given that there's no code in the same
function that interacts with the hardware.
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