adi,ad7879.yaml

  1# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
  2%YAML 1.2
  3---
  4$id: http://devicetree.org/schemas/input/touchscreen/adi,ad7879.yaml#
  5$schema: http://devicetree.org/meta-schemas/core.yaml#
  6
  7title: Analog Devices AD7879(-1)/AD7889(-1) touchscreen interface (SPI/I2C)
  8
  9maintainers:
 10  - Frank Li <Frank.Li@nxp.com>
 11
 12properties:
 13  compatible:
 14    description: |
 15      for SPI slave, use "adi,ad7879"
 16      for I2C slave, use "adi,ad7879-1"
 17    enum:
 18      - adi,ad7879
 19      - adi,ad7879-1
 20
 21  reg:
 22    maxItems: 1
 23
 24  interrupts:
 25    maxItems: 1
 26
 27  touchscreen-max-pressure:
 28    $ref: /schemas/types.yaml#/definitions/uint32
 29    description: maximum reported pressure
 30
 31  adi,resistance-plate-x:
 32    $ref: /schemas/types.yaml#/definitions/uint32
 33    description: total resistance of X-plate (for pressure calculation)
 34
 35  touchscreen-swapped-x-y:
 36    $ref: /schemas/types.yaml#/definitions/flag
 37    description: X and Y axis are swapped (boolean)
 38
 39  adi,first-conversion-delay:
 40    $ref: /schemas/types.yaml#/definitions/uint8
 41    default: 0
 42    minimum: 0
 43    maximum: 15
 44    description: |
 45      0-12: In 128us steps (starting with 128us)
 46      13  : 2.560ms
 47      14  : 3.584ms
 48      15  : 4.096ms
 49      This property has to be a '/bits/ 8' value
 50
 51  adi,acquisition-time:
 52    $ref: /schemas/types.yaml#/definitions/uint8
 53    default: 0
 54    enum: [0, 1, 2, 3]
 55    description: |
 56      0: 2us
 57      1: 4us
 58      2: 8us
 59      3: 16us
 60      This property has to be a '/bits/ 8' value
 61
 62  adi,median-filter-size:
 63    $ref: /schemas/types.yaml#/definitions/uint8
 64    default: 0
 65    enum: [0, 1, 2, 3]
 66    description: |
 67      0: disabled
 68      1: 4 measurements
 69      2: 8 measurements
 70      3: 16 measurements
 71      This property has to be a '/bits/ 8' value
 72
 73  adi,averaging:
 74    $ref: /schemas/types.yaml#/definitions/uint8
 75    default: 0
 76    enum: [0, 1, 2, 3]
 77    description: |
 78      0: 2 middle values (1 if median disabled)
 79      1: 4 middle values
 80      2: 8 middle values
 81      3: 16 values
 82      This property has to be a '/bits/ 8' value
 83
 84  adi,conversion-interval:
 85    $ref: /schemas/types.yaml#/definitions/uint8
 86    default: 0
 87    description: |
 88      0    : convert one time only
 89      1-255: 515us + val * 35us (up to 9.440ms)
 90      This property has to be a '/bits/ 8' value
 91
 92  gpio-controller: true
 93
 94  "#gpio-cells":
 95    const: 1
 96
 97required:
 98  - compatible
 99  - reg
100
101allOf:
102  - $ref: /schemas/spi/spi-peripheral-props.yaml
103
104unevaluatedProperties: false
105
106examples:
107  - |
108    #include <dt-bindings/interrupt-controller/irq.h>
109    i2c {
110        #address-cells = <1>;
111        #size-cells = <0>;
112
113        touchscreen0@2c {
114            compatible = "adi,ad7879-1";
115            reg = <0x2c>;
116            interrupt-parent = <&gpio1>;
117            interrupts = <13 IRQ_TYPE_EDGE_FALLING>;
118            touchscreen-max-pressure = <4096>;
119            adi,resistance-plate-x = <120>;
120            adi,first-conversion-delay = /bits/ 8 <3>;
121            adi,acquisition-time = /bits/ 8 <1>;
122            adi,median-filter-size = /bits/ 8 <2>;
123            adi,averaging = /bits/ 8 <1>;
124            adi,conversion-interval = /bits/ 8 <255>;
125        };
126    };
127
128  - |
129    #include <dt-bindings/interrupt-controller/irq.h>
130    spi {
131        #address-cells = <1>;
132        #size-cells = <0>;
133
134        touchscreen1@1 {
135            compatible = "adi,ad7879";
136            reg = <1>;
137            spi-max-frequency = <5000000>;
138            gpio-controller;
139            #gpio-cells = <1>;
140            interrupt-parent = <&gpio1>;
141            interrupts = <13 IRQ_TYPE_EDGE_FALLING>;
142            touchscreen-max-pressure = <4096>;
143            adi,resistance-plate-x = <120>;
144            adi,first-conversion-delay = /bits/ 8 <3>;
145            adi,acquisition-time = /bits/ 8 <1>;
146            adi,median-filter-size = /bits/ 8 <2>;
147            adi,averaging = /bits/ 8 <1>;
148            adi,conversion-interval = /bits/ 8 <255>;
149        };
150    };