TSI channel has a 4 channel mux connected to it and is normally
used for touchscreen support. The hardware may alternatively
use it as general purpose adc.
Acked-by: NGuenter Roeck <linux@roeck-us.net>
Signed-off-by: NSebastian Reichel <sebastian.reichel@collabora.co.uk>
Signed-off-by: NLee Jones <lee.jones@linaro.org>