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-rw-r--r--Documentation/devicetree/bindings/iio/adc/at91-sama5d2_adc.txt9
-rw-r--r--Documentation/devicetree/bindings/input/touchscreen/resistive-adc-touch.txt30
-rw-r--r--Documentation/devicetree/bindings/input/touchscreen/touchscreen.txt3
3 files changed, 42 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/iio/adc/at91-sama5d2_adc.txt b/Documentation/devicetree/bindings/iio/adc/at91-sama5d2_adc.txt
index 6469a4cd2a6d..4a3c1d496e1a 100644
--- a/Documentation/devicetree/bindings/iio/adc/at91-sama5d2_adc.txt
+++ b/Documentation/devicetree/bindings/iio/adc/at91-sama5d2_adc.txt
@@ -21,6 +21,14 @@ Optional properties:
- dmas: Phandle to dma channel for the ADC.
- dma-names: Must be "rx" when dmas property is being used.
See ../../dma/dma.txt for details.
+ - #io-channel-cells: in case consumer drivers are attached, this must be 1.
+ See <Documentation/devicetree/bindings/iio/iio-bindings.txt> for details.
+
+Properties for consumer drivers:
+ - Consumer drivers can be connected to this producer device, as specified
+ in <Documentation/devicetree/bindings/iio/iio-bindings.txt>
+ - Channels exposed are specified in:
+ <dt-bindings/iio/adc/at91-sama5d2_adc.txt>
Example:
@@ -38,4 +46,5 @@ adc: adc@fc030000 {
atmel,trigger-edge-type = <IRQ_TYPE_EDGE_BOTH>;
dmas = <&dma0 (AT91_XDMAC_DT_MEM_IF(0) | AT91_XDMAC_DT_PER_IF(1) | AT91_XDMAC_DT_PERID(25))>;
dma-names = "rx";
+ #io-channel-cells = <1>;
}
diff --git a/Documentation/devicetree/bindings/input/touchscreen/resistive-adc-touch.txt b/Documentation/devicetree/bindings/input/touchscreen/resistive-adc-touch.txt
new file mode 100644
index 000000000000..51456c0e9a27
--- /dev/null
+++ b/Documentation/devicetree/bindings/input/touchscreen/resistive-adc-touch.txt
@@ -0,0 +1,30 @@
+Generic resistive touchscreen ADC
+
+Required properties:
+
+ - compatible: must be "resistive-adc-touch"
+The device must be connected to an ADC 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 ADC device.
+These should correspond to the channels exposed by the ADC device and should
+have the right index as the ADC 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 ADC 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".
+
+Example:
+
+ resistive_touch: resistive_touch {
+ compatible = "resistive-adc-touch";
+ touchscreen-min-pressure = <50000>;
+ io-channels = <&adc 24>, <&adc 25>, <&adc 26>;
+ io-channel-names = "x", "y", "pressure";
+ };
diff --git a/Documentation/devicetree/bindings/input/touchscreen/touchscreen.txt b/Documentation/devicetree/bindings/input/touchscreen/touchscreen.txt
index 537643e86f61..d092d5d033a0 100644
--- a/Documentation/devicetree/bindings/input/touchscreen/touchscreen.txt
+++ b/Documentation/devicetree/bindings/input/touchscreen/touchscreen.txt
@@ -7,6 +7,9 @@ Optional properties for Touchscreens:
(in pixels)
- touchscreen-max-pressure : maximum reported pressure (arbitrary range
dependent on the controller)
+ - touchscreen-min-pressure : minimum pressure on the touchscreen to be
+ achieved in order for the touchscreen
+ driver to report a touch event.
- touchscreen-fuzz-x : horizontal noise value of the absolute input
device (in pixels)
- touchscreen-fuzz-y : vertical noise value of the absolute input
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