Allow microphone detection on WM8962 to be performed using the interrupt
signal, allowing the detection of both microphone presence and button
presses with a signal singal from the CODEC to CPU.  Currently a 250ms
debounce time is applied to both short circuit and presence detection,
this has not been optimised.
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: NLiam Girdwood <lrg@slimlogic.co.uk>

The WM8962 features five GPIOs, add support for controlling their output
state via gpiolib.
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: NLiam Girdwood <lrg@slimlogic.co.uk>

No notable changes, currently build tested only.
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

The WM8962 is a low power, high performance stereo CODEC designed for
portable digital audio applications.

This initial driver release supports the key audio paths of the WM8962.
Extended functionality, such as microphone detection, digital microphones
and the advanced DSP signal enhancements provided by the device are not
yet supported.
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>