espressif,esp32-touch

Description

Zephyr input touch sensor parent node

This defines a group of touch sensors that can generate input events. Each touch
sensor is defined in a child node of the touch-sensor node and defines a specific key
code.

For example:

#include <zephyr/dt-bindings/input/input-event-codes.h>
#include <zephyr/dt-bindings/input/esp32-touch-sensor-input.h>

&touch {
       compatible = "espressif,esp32-touch";
       status = "okay";

       debounce-interval-ms = <30>;
       href-microvolt = <27000000>;
       lref-microvolt = <500000>;
       href-atten-microvolt = <1000000>;
       filter-mode = <ESP32_TOUCH_FILTER_MODE_IIR_16>;
       filter-debounce-cnt = <1>;
       filter-noise-thr = <ESP32_TOUCH_FILTER_NOISE_THR_4_8TH>;
       filter-jitter-step = <4>;
       filter-smooth-level = <ESP32_TOUCH_FILTER_SMOOTH_MODE_IIR_2>;

       touch_sensor_0 {
               channel-num = <1>;
               channel-sens = <20>;
               zephyr,code = <INPUT_KEY_0>;
       };
};

Properties

Top level properties

These property descriptions apply to “espressif,esp32-touch” nodes themselves. This page also describes child node properties in the following sections.

Properties not inherited from the base binding file.

Name	Type	Details
`debounce-interval-ms`	`int`	Debouncing interval time in milliseconds. Default value: `30`
`href-microvolt`	`int`	Touch sensor high reference voltage. Default value: `2700000` Legal values: `2400000`, `2500000`, `2500000`, `2700000`
`lref-microvolt`	`int`	Touch sensor low reference voltage. Default value: `500000` Legal values: `500000`, `600000`, `700000`, `800000`
`href-atten-microvolt`	`int`	Touch sensor high reference attenuation voltage. Default value: `1000000` Legal values: `1500000`, `1000000`, `500000`, `0`
`filter-mode`	`int`	Touch sensor IIR filter coefficient. If not specified defaults to ESP32_TOUCH_FILTER_MODE_IIR_16. Default value: `2`
`filter-debounce-cnt`	`int`	Touch sensor debounce count. If not specified defaults to 1. Default value: `1`
`filter-noise-thr`	`int`	Touch sensor noise threshold coefficient. If not specified defaults to ESP32_TOUCH_FILTER_NOISE_THR_4_8TH.
`filter-jitter-step`	`int`	Touch sensor jitter filter step size. If not specified defaults to 4. Default value: `4`
`filter-smooth-level`	`int`	Touch sensor level of filter applied on the original data against large noise interference. If not specified defaults to ESP32_TOUCH_FILTER_SMOOTH_MODE_IIR_2. Default value: `1`

Properties inherited from the base binding file, which defines common properties that may be set on many nodes. Not all of these may apply to the “espressif,esp32-touch” compatible.

Name	Type	Details
`wakeup-source`	`boolean`	Property to identify that a device can be used as wake up source. When this property is provided a specific flag is set into the device that tells the system that the device is capable of wake up the system. Wake up capable devices are disabled (interruptions will not wake up the system) by default but they can be enabled at runtime if necessary.
`zephyr,pm-device-runtime-auto`	`boolean`	Automatically configure the device for runtime power management after the init function runs.
`zephyr,disabling-power-states`	`phandles`	List of power states that will disable this device power.
`status`	`string`	indicates the operational status of a device Legal values: `'ok'`, `'okay'`, `'disabled'`, `'reserved'`, `'fail'`, `'fail-sss'` See Important properties for more information.
`compatible`	`string-array`	compatible strings This property is required. See Important properties for more information.
`reg`	`array`	register space See Important properties for more information.
`reg-names`	`string-array`	name of each register space
`interrupts`	`array`	interrupts for device See Important properties for more information.
`interrupts-extended`	`compound`	extended interrupt specifier for device
`interrupt-names`	`string-array`	name of each interrupt
`interrupt-parent`	`phandle`	phandle to interrupt controller node
`label`	`string`	Human readable string describing the device (used as device_get_binding() argument) See Important properties for more information. This property is deprecated.
`clocks`	`phandle-array`	Clock gate information
`clock-names`	`string-array`	name of each clock
`#address-cells`	`int`	number of address cells in reg property
`#size-cells`	`int`	number of size cells in reg property
`dmas`	`phandle-array`	DMA channels specifiers
`dma-names`	`string-array`	Provided names of DMA channel specifiers
`io-channels`	`phandle-array`	IO channels specifiers
`io-channel-names`	`string-array`	Provided names of IO channel specifiers
`mboxes`	`phandle-array`	mailbox / IPM channels specifiers
`mbox-names`	`string-array`	Provided names of mailbox / IPM channel specifiers
`power-domains`	`phandle-array`	Power domain specifiers
`power-domain-names`	`string-array`	Provided names of power domain specifiers
`#power-domain-cells`	`int`	Number of cells in power-domains property
`zephyr,deferred-init`	`boolean`	Do not initialize device automatically on boot. Device should be manually initialized using device_init().

Child node properties

Name	Type	Details
`channel-num`	`int`	Touch sensor channel number This property is required.
`channel-sens`	`int`	Touch sensor channel sensibility in 100th. If not specified defaults to 20. Default value: `20`
`zephyr,code`	`int`	Key code to emit. This property is required.