[PATCH v2 03/10] dt-bindings: input: touchscreen: touch_adc: create bindings

From: Eugen Hristev
Date: Tue Mar 27 2018 - 08:37:27 EST


Added bindings for generic resistive touchscreen ADC.

Signed-off-by: Eugen Hristev <eugen.hristev@xxxxxxxxxxxxx>
---
Changes in v2:
- modified bindings to have a generic resistive touchscreen adc driver
instead of specific architecture one.

.../bindings/input/touchscreen/touch_adc.txt | 33 ++++++++++++++++++++++
1 file changed, 33 insertions(+)
create mode 100644 Documentation/devicetree/bindings/input/touchscreen/touch_adc.txt

diff --git a/Documentation/devicetree/bindings/input/touchscreen/touch_adc.txt b/Documentation/devicetree/bindings/input/touchscreen/touch_adc.txt
new file mode 100644
index 0000000..27abcdc
--- /dev/null
+++ b/Documentation/devicetree/bindings/input/touchscreen/touch_adc.txt
@@ -0,0 +1,33 @@
+Generic resistive touchscreen ADC
+
+Required properties:
+
+ - compatible: must be "generic-resistive-adc-touch"
+The device must be connected to an IIO device that provides channels for
+position measurement and optional pressure.
+Refer to ../iio/iio-bindings.txt for details
+ - iio-channels: must have at least two channels connected to an IIO device.
+These should correspond to the channels exposed by the IIO device and should
+have the right index as the IIO device registers them. These channels
+represent the relative position on the "x" and "y" axes.
+ - iio-channel-names: must have all the channels' names. Mandatory channels
+are "x" and "y".
+
+Optional properties:
+ - iio-channels: The third channel named "pressure" is optional and can be
+used if the IIO device also measures pressure besides position.
+If this channel is missing, pressure will be ignored and the touchscreen
+will only report position.
+ - iio-channel-names: optional channel named "pressure".
+ - generic-resistive-adc-touch,pressure-threshold: a pressure threshold for
+the touchscreen, if we are using the "pressure" channel as well.
+Represented by an integer value.
+
+Example:
+
+ resistive_touch: resistive_touch {
+ compatible = "generic-resistive-adc-touch";
+ generic-resistive-adc-touch,pressure-threshold = <10000>;
+ io-channels = <&adc 24>, <&adc 25>, <&adc 26>;
+ io-channel-names = "x", "y", "pressure";
+ };
--
2.7.4