From ff07004f4b9c5f5589e0821afd3db1e86e1102c4 Mon Sep 17 00:00:00 2001 From: Markus Pargmann Date: Mon, 14 Dec 2015 14:53:49 +0100 Subject: Input: add binding documentation for imx25 touchscreen controller This is the touchscreen conversion queue binding documentation. It uses the shared imx25 ADC. Signed-off-by: Markus Pargmann Acked-by: Rob Herring Signed-off-by: Lee Jones --- .../bindings/input/touchscreen/fsl-mx25-tcq.txt | 35 ++++++++++++++++++++++ 1 file changed, 35 insertions(+) create mode 100644 Documentation/devicetree/bindings/input/touchscreen/fsl-mx25-tcq.txt (limited to 'Documentation/devicetree/bindings/input') diff --git a/Documentation/devicetree/bindings/input/touchscreen/fsl-mx25-tcq.txt b/Documentation/devicetree/bindings/input/touchscreen/fsl-mx25-tcq.txt new file mode 100644 index 000000000000..cdf05f9b2329 --- /dev/null +++ b/Documentation/devicetree/bindings/input/touchscreen/fsl-mx25-tcq.txt @@ -0,0 +1,35 @@ +Freescale mx25 TS conversion queue module + +mx25 touchscreen conversion queue module which controls the ADC unit of the +mx25 for attached touchscreens. + +Required properties: + - compatible: Should be "fsl,imx25-tcq". + - reg: Memory range of the device. + - interrupts: Should be the interrupt number associated with this module within + the tscadc unit (<0>). + - interrupt-parent: Should be a phandle to the tscadc unit. + - fsl,wires: Should be '<4>' or '<5>' + +Optional properties: + - fsl,pen-debounce-ns: Pen debounce time in nanoseconds. + - fsl,pen-threshold: Pen-down threshold for the touchscreen. This is a value + between 1 and 4096. It is the ratio between the internal reference voltage + and the measured voltage after the plate was precharged. Resistence between + plates and therefore the voltage decreases with pressure so that a smaller + value is equivalent to a higher pressure. + - fsl,settling-time-ns: Settling time in nanoseconds. The settling time is before + the actual touch detection to wait for an even charge distribution in the + plate. + +This device includes two conversion queues which can be added as subnodes. +The first queue is for the touchscreen, the second for general purpose ADC. + +Example: + tsc: tcq@50030400 { + compatible = "fsl,imx25-tcq"; + reg = <0x50030400 0x60>; + interrupt-parent = <&tscadc>; + interrupts = <0>; + fsl,wires = <4>; + }; -- cgit v1.2.3 From 299b207dbce8d19cafdc57f50e79883319ba962e Mon Sep 17 00:00:00 2001 From: Alexander Stein Date: Mon, 29 Feb 2016 08:06:35 +0100 Subject: Input: ads7846: Add description how to use internal reference (ADS7846) By simply setting vref-mv to 0 the internal reference will be used. Document that! Signed-off-by: Alexander Stein Signed-off-by: Rob Herring --- Documentation/devicetree/bindings/input/ads7846.txt | 2 ++ 1 file changed, 2 insertions(+) (limited to 'Documentation/devicetree/bindings/input') diff --git a/Documentation/devicetree/bindings/input/ads7846.txt b/Documentation/devicetree/bindings/input/ads7846.txt index 33a1638b61d6..c6cfe2e3ed41 100644 --- a/Documentation/devicetree/bindings/input/ads7846.txt +++ b/Documentation/devicetree/bindings/input/ads7846.txt @@ -29,6 +29,8 @@ Optional properties: ti,vref-delay-usecs vref supply delay in usecs, 0 for external vref (u16). ti,vref-mv The VREF voltage, in millivolts (u16). + Set to 0 to use internal refernce + (ADS7846). ti,keep-vref-on set to keep vref on for differential measurements as well ti,swap-xy swap x and y axis -- cgit v1.2.3