[PATCH v9 3/8] ARM: dt: Binding documentation for imx25 touchscreen controller

[Rob Herring]

On Sun, Dec 06, 2015 at 08:52:16PM +0100, Markus Pargmann wrote:
> This is the touchscreen conversion queue binding documentation. It uses
> the shared imx25 ADC.
> 
> Signed-off-by: Markus Pargmann <mpa at pengutronix.de>
> ---
> 
> Notes:
>     Changes in v9:
>      - Updated binding descriptions
>     
>     Changes in v5:
>      - Fix signed/unsigned comparison
>      - Fix unused variable settling_time by putting it in the correct argument list
>      - Use continous conversion queue with the repeat feature and a proper
>        repeat-wait. Previously the touchscreen caused massive number of interrupts.
> 
>  .../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
> 
> 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..d45e50872114
> --- /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: Pen debounce time in nanoseconds.

This and ...

> + - 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: Settling time in nanoseconds. The settling time is before
> +   the actual touch detection to wait for an even charge distribution in the
> +   plate.

... this still need units (-ns) appended to the property name.

> +
> +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 at 50030400 {
> +		compatible = "fsl,imx25-tcq";
> +		reg = <0x50030400 0x60>;
> +		interrupt-parent = <&tscadc>;
> +		interrupts = <0>;
> +		fsl,wires = <4>;
> +	};
> -- 
> 2.6.2
> 
> --
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