xref: /linux/Documentation/devicetree/bindings/iio/adc/adi,ad7780.yaml (revision f7f0adfe64de08803990dc4cbecd2849c04e314a) 
1# SPDX-License-Identifier: GPL-2.0
2%YAML 1.2
3---
4$id: http://devicetree.org/schemas/iio/adc/adi,ad7780.yaml#
5$schema: http://devicetree.org/meta-schemas/core.yaml#
6
7title: Analog Devices AD7170/AD7171/AD7780/AD7781 analog to digital converters
8
9maintainers:
10  - Michael Hennerich <michael.hennerich@analog.com>
11
12description: |
13  The ad7780 is a sigma-delta analog to digital converter. This driver provides
14  reading voltage values and status bits from both the ad778x and ad717x series.
15  Its interface also allows writing on the FILTER and GAIN GPIO pins on the
16  ad778x.
17
18  Specifications on the converters can be found at:
19    AD7170:
20      https://www.analog.com/media/en/technical-documentation/data-sheets/AD7170.pdf
21    AD7171:
22      https://www.analog.com/media/en/technical-documentation/data-sheets/AD7171.pdf
23    AD7780:
24      https://www.analog.com/media/en/technical-documentation/data-sheets/ad7780.pdf
25    AD7781:
26      https://www.analog.com/media/en/technical-documentation/data-sheets/AD7781.pdf
27
28properties:
29  compatible:
30    enum:
31      - adi,ad7170
32      - adi,ad7171
33      - adi,ad7780
34      - adi,ad7781
35
36  reg:
37    maxItems: 1
38
39  avdd-supply:
40    description:
41      The regulator supply for the ADC reference voltage.
42
43  powerdown-gpios:
44    description:
45      Must be the device tree identifier of the PDRST pin. If
46      specified, it will be asserted during driver probe. As the
47      line is active high, it should be marked GPIO_ACTIVE_HIGH.
48    maxItems: 1
49
50  adi,gain-gpios:
51    description:
52      Must be the device tree identifier of the GAIN pin. Only for
53      the ad778x chips. If specified, it will be asserted during
54      driver probe. As the line is active low, it should be marked
55      GPIO_ACTIVE_LOW.
56    maxItems: 1
57
58  adi,filter-gpios:
59    description:
60      Must be the device tree identifier of the FILTER pin. Only
61      for the ad778x chips. If specified, it will be asserted
62      during driver probe. As the line is active low, it should be
63      marked GPIO_ACTIVE_LOW.
64    maxItems: 1
65
66  rdy-gpios:
67    description:
68      GPIO reading the R̅D̅Y̅ line. Having such a GPIO is technically optional but
69      highly recommended because DOUT/R̅D̅Y̅ toggles during SPI transfers (in its
70      DOUT aka MISO role) and so usually triggers a spurious interrupt. The
71      distinction between such a spurious event and a real one can only be done
72      by reading such a GPIO. (There is a register telling the same
73      information, but accessing that one needs a SPI transfer which then
74      triggers another interrupt event.)
75    maxItems: 1
76
77required:
78  - compatible
79  - reg
80
81additionalProperties: false
82
83examples:
84  - |
85    #include <dt-bindings/gpio/gpio.h>
86    spi {
87        #address-cells = <1>;
88        #size-cells = <0>;
89
90        adc@0 {
91            compatible = "adi,ad7780";
92            reg = <0>;
93
94            avdd-supply = <&vdd_supply>;
95            powerdown-gpios = <&gpio0 12 GPIO_ACTIVE_HIGH>;
96            adi,gain-gpios = <&gpio1  5 GPIO_ACTIVE_LOW>;
97            adi,filter-gpios = <&gpio2 15 GPIO_ACTIVE_LOW>;
98        };
99    };
100