M7350/kernel/Documentation/devicetree/bindings/input/touchscreen/stmpe.txt

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2024-09-09 08:57:42 +00:00
STMPE Touchscreen
----------------
Required properties:
- compatible: "st,stmpe-ts"
Optional properties:
- st,sample-time: ADC converstion time in number of clock. (0 -> 36 clocks, 1 ->
44 clocks, 2 -> 56 clocks, 3 -> 64 clocks, 4 -> 80 clocks, 5 -> 96 clocks, 6
-> 144 clocks), recommended is 4.
- st,mod-12b: ADC Bit mode (0 -> 10bit ADC, 1 -> 12bit ADC)
- st,ref-sel: ADC reference source (0 -> internal reference, 1 -> external
reference)
- st,adc-freq: ADC Clock speed (0 -> 1.625 MHz, 1 -> 3.25 MHz, 2 || 3 -> 6.5 MHz)
- st,ave-ctrl: Sample average control (0 -> 1 sample, 1 -> 2 samples, 2 -> 4
samples, 3 -> 8 samples)
- st,touch-det-delay: Touch detect interrupt delay (0 -> 10 us, 1 -> 50 us, 2 ->
100 us, 3 -> 500 us, 4-> 1 ms, 5 -> 5 ms, 6 -> 10 ms, 7 -> 50 ms) recommended
is 3
- st,settling: Panel driver settling time (0 -> 10 us, 1 -> 100 us, 2 -> 500 us, 3
-> 1 ms, 4 -> 5 ms, 5 -> 10 ms, 6 for 50 ms, 7 -> 100 ms) recommended is 2
- st,fraction-z: Length of the fractional part in z (fraction-z ([0..7]) = Count of
the fractional part) recommended is 7
- st,i-drive: current limit value of the touchscreen drivers (0 -> 20 mA typical 35
mA max, 1 -> 50 mA typical 80 mA max)
Node name must be stmpe_touchscreen and should be child node of stmpe node to
which it belongs.
Example:
stmpe_touchscreen {
compatible = "st,stmpe-ts";
st,sample-time = <4>;
st,mod-12b = <1>;
st,ref-sel = <0>;
st,adc-freq = <1>;
st,ave-ctrl = <1>;
st,touch-det-delay = <2>;
st,settling = <2>;
st,fraction-z = <7>;
st,i-drive = <1>;
};