[alsa-devel] AC97 reset fail after suspend
broonie at opensource.wolfsonmicro.com
Thu May 14 16:25:10 CEST 2009
On Thu, May 14, 2009 at 03:51:37PM +0200, Marek Vasut wrote:
> On Thursday 14 of May 2009 14:32:41 Mark Brown wrote:
> > needed to start the link. I'll need to check but IIRC the WM9712 runs
> > the link by default and I can't see any changes to this behaviour in the
> > driver changelog.
> Well without this, the codec doesn't kick in (reading the registers returns
> all zeros) so I assume that's the same issue as on wm9713.
OK, I've checked - there is actually a resistor strap option on the
CODEC to control if the device powers on with the AC97 link enabled or
disabled by default. This must be the first Linux device that chooses
the second option, I guess. A version of your patch would be good, but
it should check for warm reset support in the AC97 controller before it
tries to use it since the chip won't always need the warm reset.
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