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+* Analog Devices AD7879(-1)/AD7889(-1) touchscreen interface (SPI/I2C)
+
+Required properties:
+- compatible : for SPI slave, use "adi,ad7879"
+ for I2C slave, use "adi,ad7879-1"
+- reg : SPI chipselect/I2C slave address
+ See spi-bus.txt for more SPI slave properties
+- interrupts : touch controller interrupt
+- touchscreen-max-pressure : maximum reported pressure
+- adi,resistance-plate-x : total resistance of X-plate (for pressure
+ calculation)
+Optional properties:
+- touchscreen-swapped-x-y : X and Y axis are swapped (boolean)
+- adi,first-conversion-delay : 0-12: In 128us steps (starting with 128us)
+ 13 : 2.560ms
+ 14 : 3.584ms
+ 15 : 4.096ms
+ This property has to be a '/bits/ 8' value
+- adi,acquisition-time : 0: 2us
+ 1: 4us
+ 2: 8us
+ 3: 16us
+ This property has to be a '/bits/ 8' value
+- adi,median-filter-size : 0: disabled
+ 1: 4 measurements
+ 2: 8 measurements
+ 3: 16 measurements
+ This property has to be a '/bits/ 8' value
+- adi,averaging : 0: 2 middle values (1 if median disabled)
+ 1: 4 middle values
+ 2: 8 middle values
+ 3: 16 values
+ This property has to be a '/bits/ 8' value
+- adi,conversion-interval: : 0 : convert one time only
+ 1-255: 515us + val * 35us (up to 9.440ms)
+ This property has to be a '/bits/ 8' value
+- gpio-controller : Switch AUX/VBAT/GPIO pin to GPIO mode
+
+Example:
+
+ touchscreen0@2c {
+ compatible = "adi,ad7879-1";
+ reg = <0x2c>;
+ interrupt-parent = <&gpio1>;
+ interrupts = <13 IRQ_TYPE_EDGE_FALLING>;
+ touchscreen-max-pressure = <4096>;
+ adi,resistance-plate-x = <120>;
+ adi,first-conversion-delay = /bits/ 8 <3>;
+ adi,acquisition-time = /bits/ 8 <1>;
+ adi,median-filter-size = /bits/ 8 <2>;
+ adi,averaging = /bits/ 8 <1>;
+ adi,conversion-interval = /bits/ 8 <255>;
+ };
+
+ touchscreen1@1 {
+ compatible = "adi,ad7879";
+ spi-max-frequency = <5000000>;
+ reg = <1>;
+ spi-cpol;
+ spi-cpha;
+ gpio-controller;
+ interrupt-parent = <&gpio1>;
+ interrupts = <13 IRQ_TYPE_EDGE_FALLING>;
+ touchscreen-max-pressure = <4096>;
+ adi,resistance-plate-x = <120>;
+ adi,first-conversion-delay = /bits/ 8 <3>;
+ adi,acquisition-time = /bits/ 8 <1>;
+ adi,median-filter-size = /bits/ 8 <2>;
+ adi,averaging = /bits/ 8 <1>;
+ adi,conversion-interval = /bits/ 8 <255>;
+ };