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- 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. Resistance 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>;
- };
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