The previous implementation already reported a key-press event after
reading an ADC value close to the threshold for the first time.
This may lead to false events if the ADC takes a reading just during
the transition from one button state to another (especially if a
somewhat large capacitor is used to avoid noise).
A key-press state must be same for at least two samples in order to
avoid such issues, which is what this commit implements.
Signed-off-by: Martin Jäger <martin@libre.solar>
Building with GCC 9.4.0 gives the following warning/error:
error: closest_mv may be used uninitialized in this function
This commit fixes it.
Signed-off-by: Robert Lubos <robert.lubos@nordicsemi.no>
This commit introduces a driver for ADC keys, a common circuit design where
keys are connected to an ADC input via a resistor ladder.
Signed-off-by: Chen Xingyu <hi@xingrz.me>
