| 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>). |
| - 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>; |
| }; |
