linuxdebug/Documentation/devicetree/bindings/input/touchscreen/stmpe.txt

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STMPE Touchscreen
----------------
Required properties:
- compatible: "st,stmpe-ts"
Optional properties:
- 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 (recommended is 3)
0 -> 10 us
1 -> 50 us
2 -> 100 us
3 -> 500 us
4 -> 1 ms
5 -> 5 ms
6 -> 10 ms
7 -> 50 ms
- st,settling : Panel driver settling time (recommended is 2)
0 -> 10 us
1 -> 100 us
2 -> 500 us
3 -> 1 ms
4 -> 5 ms
5 -> 10 ms
6 -> 50 ms
7 -> 100 ms
- st,fraction-z : Length of the fractional part in z (recommended is 7)
(fraction-z ([0..7]) = Count of the fractional part)
- st,i-drive : current limit value of the touchscreen drivers
0 -> 20 mA (typical 35mA max)
1 -> 50 mA (typical 80 mA max)
Optional properties common with MFD (deprecated):
- st,sample-time : ADC conversion time in number of clock.
0 -> 36 clocks
1 -> 44 clocks
2 -> 56 clocks
3 -> 64 clocks
4 -> 80 clocks (recommended)
5 -> 96 clocks
6 -> 124 clocks
- st,mod-12b : ADC Bit mode
0 -> 10bit ADC
1 -> 12bit ADC
- st,ref-sel : ADC reference source
0 -> internal
1 -> external
- st,adc-freq : ADC Clock speed
0 -> 1.625 MHz
1 -> 3.25 MHz
2 || 3 -> 6.5 MHz
Node should be child node of stmpe node to which it belongs.
Note that common ADC settings of stmpe_touchscreen (child) will take precedence
over the settings done in MFD.
Example:
stmpe811@41 {
compatible = "st,stmpe811";
pinctrl-names = "default";
pinctrl-0 = <&pinctrl_touch_int>;
#address-cells = <1>;
#size-cells = <0>;
reg = <0x41>;
interrupts = <10 IRQ_TYPE_LEVEL_LOW>;
interrupt-parent = <&gpio4>;
interrupt-controller;
id = <0>;
blocks = <0x5>;
irq-trigger = <0x1>;
/* Common ADC settings */
/* 3.25 MHz ADC clock speed */
st,adc-freq = <1>;
/* 12-bit ADC */
st,mod-12b = <1>;
/* internal ADC reference */
st,ref-sel = <0>;
/* ADC converstion time: 80 clocks */
st,sample-time = <4>;
stmpe_touchscreen {
compatible = "st,stmpe-ts";
reg = <0>;
/* 8 sample average control */
st,ave-ctrl = <3>;
/* 5 ms touch detect interrupt delay */
st,touch-det-delay = <5>;
/* 1 ms panel driver settling time */
st,settling = <3>;
/* 7 length fractional part in z */
st,fraction-z = <7>;
/*
* 50 mA typical 80 mA max touchscreen drivers
* current limit value
*/
st,i-drive = <1>;
};
stmpe_adc {
compatible = "st,stmpe-adc";
st,norequest-mask = <0x0F>;
};
};