[PATCH v6 1/3] dt-bindings: iio: adc: add AD7191

Alisa-Dariana Roman
2025-02-28T14:13:51Z

AD7191 is a pin-programmable, ultra-low noise 24-bit sigma-delta ADC
designed for precision bridge sensor measurements. It features two
differential analog input channels, selectable output rates,
programmable gain, internal temperature sensor and simultaneous
50Hz/60Hz rejection.

Signed-off-by: Alisa-Dariana Roman <alisa.roman@analog.com>
Reviewed-by: Rob Herring (Arm) <robh@kernel.org>
---
.../bindings/iio/adc/adi,ad7191.yaml | 149 ++++++++++++++++++
MAINTAINERS | 7 +
2 files changed, 156 insertions(+)
create mode 100644 Documentation/devicetree/bindings/iio/adc/adi,ad7191.yaml

diff --git a/Documentation/devicetree/bindings/iio/adc/adi,ad7191.yaml b/Documentation/devicetree/bindings/iio/adc/adi,ad7191.yaml
new file mode 100644
index 000000000000..801ed319ee82
--- /dev/null
+++ b/Documentation/devicetree/bindings/iio/adc/adi,ad7191.yaml
@@ -0,0 +1,149 @@
+# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
+# Copyright 2025 Analog Devices Inc.
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/iio/adc/adi,ad7191.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Analog Devices AD7191 ADC
+
+maintainers:
+ - Alisa-Dariana Roman <alisa.roman@analog.com>
+
+description: |
+ Bindings for the Analog Devices AD7191 ADC device. Datasheet can be
+ found here:
+ https://www.analog.com/media/en/technical-documentation/data-sheets/AD7191.pdf
+ The device's PDOWN pin must be connected to the SPI controller's chip select
+ pin.
+
+properties:
+ compatible:
+ enum:
+ - adi,ad7191
+
+ reg:
+ maxItems: 1
+
+ spi-cpol: true
+
+ spi-cpha: true
+
+ clocks:
+ maxItems: 1
+ description:
+ Must be present when CLKSEL pin is tied HIGH to select external clock
+ source (either a crystal between MCLK1 and MCLK2 pins, or a
+ CMOS-compatible clock driving MCLK2 pin). Must be absent when CLKSEL pin
+ is tied LOW to use the internal 4.92MHz clock.
+
+ interrupts:
+ maxItems: 1
+
+ avdd-supply:
+ description: AVdd voltage supply
+
+ dvdd-supply:
+ description: DVdd voltage supply
+
+ vref-supply:
+ description: Vref voltage supply
+
+ odr-gpios:
+ description:
+ ODR1 and ODR2 pins for output data rate selection. Should be defined if
+ adi,odr-value is absent.
+ minItems: 2
+ maxItems: 2
+
+ adi,odr-value:
+ $ref: /schemas/types.yaml#/definitions/uint32
+ description: |
+ Should be present if ODR pins are pin-strapped. Possible values:
+ 120 Hz (ODR1=0, ODR2=0)
+ 60 Hz (ODR1=0, ODR2=1)
+ 50 Hz (ODR1=1, ODR2=0)
+ 10 Hz (ODR1=1, ODR2=1)
+ If defined, odr-gpios must be absent.
+ enum: [120, 60, 50, 10]
+
+ pga-gpios:
+ description:
+ PGA1 and PGA2 pins for gain selection. Should be defined if adi,pga-value
+ is absent.
+ minItems: 2
+ maxItems: 2
+
+ adi,pga-value:
+ $ref: /schemas/types.yaml#/definitions/uint32
+ description: |
+ Should be present if PGA pins are pin-strapped. Possible values:
+ Gain 1 (PGA1=0, PGA2=0)
+ Gain 8 (PGA1=0, PGA2=1)
+ Gain 64 (PGA1=1, PGA2=0)
+ Gain 128 (PGA1=1, PGA2=1)
+ If defined, pga-gpios must be absent.
+ enum: [1, 8, 64, 128]
+
+ temp-gpios:
+ description: TEMP pin for temperature sensor enable.
+ maxItems: 1
+
+ chan-gpios:
+ description: CHAN pin for input channel selection.
+ maxItems: 1
+
+required:
+ - compatible
+ - reg
+ - interrupts
+ - avdd-supply
+ - dvdd-supply
+ - vref-supply
+ - spi-cpol
+ - spi-cpha
+ - temp-gpios
+ - chan-gpios
+
+allOf:
+ - $ref: /schemas/spi/spi-peripheral-props.yaml#
+ - oneOf:
+ - required:
+ - adi,odr-value
+ - required:
+ - odr-gpios
+ - oneOf:
+ - required:
+ - adi,pga-value
+ - required:
+ - pga-gpios
+
+unevaluatedProperties: false
+
+examples:
+ - |
+ #include <dt-bindings/gpio/gpio.h>
+ #include <dt-bindings/interrupt-controller/irq.h>
+
+ spi {
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ adc@0 {
+ compatible = "adi,ad7191";
+ reg = <0>;
+ spi-max-frequency = <1000000>;
+ spi-cpol;
+ spi-cpha;
+ clocks = <&ad7191_mclk>;
+ interrupts = <25 IRQ_TYPE_EDGE_FALLING>;
+ interrupt-parent = <&gpio>;
+ avdd-supply = <&avdd>;
+ dvdd-supply = <&dvdd>;
+ vref-supply = <&vref>;
+ adi,pga-value = <1>;
+ odr-gpios = <&gpio 23 GPIO_ACTIVE_HIGH>, <&gpio 24 GPIO_ACTIVE_HIGH>;
+ temp-gpios = <&gpio 22 GPIO_ACTIVE_HIGH>;
+ chan-gpios = <&gpio 27 GPIO_ACTIVE_HIGH>;
+ };
+ };
diff --git a/MAINTAINERS b/MAINTAINERS
index bd04375ab4a2..ac1f61256932 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -1346,6 +1346,13 @@ W: http://ez.analog.com/community/linux-device-drivers
F: Documentation/devicetree/bindings/iio/adc/adi,ad7091r*
F: drivers/iio/adc/ad7091r*

+ANALOG DEVICES INC AD7191 DRIVER
+M: Alisa-Dariana Roman <alisa.roman@analog.com>
+L: linux-iio@vger.kernel.org
+S: Supported
+W: https://ez.analog.com/linux-software-drivers
+F: Documentation/devicetree/bindings/iio/adc/adi,ad7191.yaml
+
ANALOG DEVICES INC AD7192 DRIVER
M: Alisa-Dariana Roman <alisa.roman@analog.com>
L: linux-iio@vger.kernel.org
--
2.43.0