Add I2C driver for Atmel Capacitive Touch Button device.
Signed-off-by: NHung-yu Wu <hywu@google.com>
Signed-off-by: NGrant Grundler <grundler@chromium.org>
Acked-by: NRob Herring <robh@kernel.org>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>