[alsa-devel] A question about the soc jack status

[Mark Brown]

On Wed, Oct 28, 2009 at 04:16:49PM +0900, Joonyoung Shim wrote:

> I have a question about soc jack. I know the soc jack reports the jack 
> status when the jack status is change only. For example when the jack 
> is inserted or released, the soc jack reports the jack status to user 
> via input subsystem.

> But i want to know the jack status always regardless of the event to 
> insert or release a jack. For example we can check the jack status 
> always if the jack status is reported via sysfs file.

> So, is there how to know the jack status always the currently?

You can query this with an ioctl() on the input device - EVIOCGSW()
should do the trick, evtest.c has some example code I believe.  Adding
this information to sysfs would be nice if someone has the time to look
into it.