[alsa-devel] questions about asoc jack detection

[Lu Guanqun]

On Wed, Apr 20, 2011 at 11:14:44PM +0800, Tobin Davis wrote:
> On Wed, 2011-04-20 at 23:00 +0800, Lu Guanqun wrote:
> > On Wed, Apr 20, 2011 at 10:53:58PM +0800, Mark Brown wrote:
> > > On Wed, Apr 20, 2011 at 10:06:15PM +0800, Lu Guanqun wrote:
> > > 
> > > > Yes, it's related to policy. But I see some inconsistencies in handling
> > > > this stuff. In this above example, you suggest we should play out of
> > > > both outputs. However in HDA code, the common way when headphone is
> > > > inserted is to mute the speaker and enable the headphone. Is there some
> > > > differences between the HDA code and the ASoC code? Or this is just due
> > > > to legacy code?
> > > 
> > > HDA code does this differently.  I'd argue that they've taken the wrong
> > > implementation decision and that this should be a userspace issue but
> > > the use cases for PCs are a bit more basic.
> > 
> > I agree with you that this kind of policy should be put into userspace
> > instead of hardcoding it in kernel.
> > 
> > Good to hear the points from you. Thanks!
> > 
> IIRC, the HDA jack detection code is pretty much legacy.  It has been
> around longer than udev and other prior userspace hw detection systems.

Thanks for your input.

> 
> That That doesn't mean it can't change.

Do we afford the changes? I don't think so. Lots of things have to be
changed accordingly and if we fail to fix one stuff out of the whole
chain, the end users will scream and yell at us: "You broke my PC." :)

-- 
guanqun