[PATCH v7 5/7] dt-bindings: iio: adc: Add AD4000

From: Marcelo Schmitt
Date: Fri Jul 12 2024 - 15:23:02 EST

Add device tree documentation for AD4000 series of ADC devices.

Reviewed-by: Conor Dooley <conor.dooley@xxxxxxxxxxxxx>
Signed-off-by: Marcelo Schmitt <marcelo.schmitt@xxxxxxxxxx>
---
No changes to device tree from v6 to v7.

.../bindings/iio/adc/adi,ad4000.yaml | 197 ++++++++++++++++++
MAINTAINERS | 7 +
2 files changed, 204 insertions(+)
create mode 100644 Documentation/devicetree/bindings/iio/adc/adi,ad4000.yaml

diff --git a/Documentation/devicetree/bindings/iio/adc/adi,ad4000.yaml b/Documentation/devicetree/bindings/iio/adc/adi,ad4000.yaml
new file mode 100644
index 000000000000..e413a9d8d2a2
--- /dev/null
+++ b/Documentation/devicetree/bindings/iio/adc/adi,ad4000.yaml
@@ -0,0 +1,197 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/iio/adc/adi,ad4000.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Analog Devices AD4000 and similar Analog to Digital Converters
+
+maintainers:
+ - Marcelo Schmitt <marcelo.schmitt@xxxxxxxxxx>
+
+description: |
+ Analog Devices AD4000 family of Analog to Digital Converters with SPI support.
+ Specifications can be found at:
+ https://www.analog.com/media/en/technical-documentation/data-sheets/ad4000-4004-4008.pdf
+ https://www.analog.com/media/en/technical-documentation/data-sheets/ad4001-4005.pdf
+ https://www.analog.com/media/en/technical-documentation/data-sheets/ad4002-4006-4010.pdf
+ https://www.analog.com/media/en/technical-documentation/data-sheets/ad4003-4007-4011.pdf
+ https://www.analog.com/media/en/technical-documentation/data-sheets/ad4020-4021-4022.pdf
+ https://www.analog.com/media/en/technical-documentation/data-sheets/adaq4001.pdf
+ https://www.analog.com/media/en/technical-documentation/data-sheets/adaq4003.pdf
+
+$ref: /schemas/spi/spi-peripheral-props.yaml#
+
+properties:
+ compatible:
+ oneOf:
+ - const: adi,ad4000
+ - items:
+ - enum:
+ - adi,ad4004
+ - adi,ad4008
+ - const: adi,ad4000
+
+ - const: adi,ad4001
+ - items:
+ - enum:
+ - adi,ad4005
+ - const: adi,ad4001
+
+ - const: adi,ad4002
+ - items:
+ - enum:
+ - adi,ad4006
+ - adi,ad4010
+ - const: adi,ad4002
+
+ - const: adi,ad4003
+ - items:
+ - enum:
+ - adi,ad4007
+ - adi,ad4011
+ - const: adi,ad4003
+
+ - const: adi,ad4020
+ - items:
+ - enum:
+ - adi,ad4021
+ - adi,ad4022
+ - const: adi,ad4020
+
+ - const: adi,adaq4001
+
+ - const: adi,adaq4003
+
+ reg:
+ maxItems: 1
+
+ spi-max-frequency:
+ maximum: 102040816 # for VIO > 2.7 V, 81300813 for VIO > 1.7 V
+
+ adi,sdi-pin:
+ $ref: /schemas/types.yaml#/definitions/string
+ enum: [ high, low, cs, sdi ]
+ default: sdi
+ description:
+ Describes how the ADC SDI pin is wired. A value of "sdi" indicates that
+ the ADC SDI is connected to host SDO. "high" indicates that the ADC SDI
+ pin is hard-wired to logic high (VIO). "low" indicates that it is
+ hard-wired low (GND). "cs" indicates that the ADC SDI pin is connected to
+ the host CS line.
+
+ '#daisy-chained-devices': true
+
+ vdd-supply:
+ description: A 1.8V supply that powers the chip (VDD).
+
+ vio-supply:
+ description:
+ A 1.8V to 5.5V supply for the digital inputs and outputs (VIO).
+
+ ref-supply:
+ description:
+ A 2.5 to 5V supply for the external reference voltage (REF).
+
+ cnv-gpios:
+ description:
+ When provided, this property indicates the GPIO that is connected to the
+ CNV pin.
+ maxItems: 1
+
+ adi,high-z-input:
+ type: boolean
+ description:
+ High-Z mode allows the amplifier and RC filter in front of the ADC to be
+ chosen based on the signal bandwidth of interest, rather than the settling
+ requirements of the switched capacitor SAR ADC inputs.
+
+ adi,gain-milli:
+ description: |
+ The hardware gain applied to the ADC input (in milli units).
+ The gain provided by the ADC input scaler is defined by the hardware
+ connections between chip pins OUT+, R1K-, R1K1-, R1K+, R1K1+, and OUT-.
+ If not present, default to 1000 (no actual gain applied).
+ $ref: /schemas/types.yaml#/definitions/uint16
+ enum: [454, 909, 1000, 1900]
+ default: 1000
+
+ interrupts:
+ description:
+ The SDO pin can also function as a busy indicator. This node should be
+ connected to an interrupt that is triggered when the SDO line goes low
+ while the SDI line is high and the CNV line is low ("3-wire" mode) or the
+ SDI line is low and the CNV line is high ("4-wire" mode); or when the SDO
+ line goes high while the SDI and CNV lines are high (chain mode),
+ maxItems: 1
+
+required:
+ - compatible
+ - reg
+ - vdd-supply
+ - vio-supply
+ - ref-supply
+
+allOf:
+ # The configuration register can only be accessed if SDI is connected to MOSI
+ - if:
+ required:
+ - adi,sdi-pin
+ then:
+ properties:
+ adi,high-z-input: false
+ # chain mode has lower SCLK max rate
+ - if:
+ required:
+ - '#daisy-chained-devices'
+ then:
+ properties:
+ spi-max-frequency:
+ maximum: 50000000 # for VIO > 2.7 V, 40000000 for VIO > 1.7 V
+ # Gain property only applies to ADAQ devices
+ - if:
+ properties:
+ compatible:
+ not:
+ contains:
+ enum:
+ - adi,adaq4001
+ - adi,adaq4003
+ then:
+ properties:
+ adi,gain-milli: false
+
+unevaluatedProperties: false
+
+examples:
+ - |
+ #include <dt-bindings/gpio/gpio.h>
+ spi {
+ #address-cells = <1>;
+ #size-cells = <0>;
+ adc@0 {
+ compatible = "adi,ad4020";
+ reg = <0>;
+ spi-max-frequency = <71000000>;
+ vdd-supply = <&supply_1_8V>;
+ vio-supply = <&supply_1_8V>;
+ ref-supply = <&supply_5V>;
+ adi,sdi-pin = "cs";
+ cnv-gpios = <&gpio0 88 GPIO_ACTIVE_HIGH>;
+ };
+ };
+ - |
+ spi {
+ #address-cells = <1>;
+ #size-cells = <0>;
+ adc@0 {
+ compatible = "adi,adaq4003";
+ reg = <0>;
+ spi-max-frequency = <80000000>;
+ vdd-supply = <&supply_1_8V>;
+ vio-supply = <&supply_1_8V>;
+ ref-supply = <&supply_5V>;
+ adi,high-z-input;
+ adi,gain-milli = /bits/ 16 <454>;
+ };
+ };
diff --git a/MAINTAINERS b/MAINTAINERS
index 06ecfa64a39a..e03300d3ef13 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -1199,6 +1199,13 @@ W: https://ez.analog.com/linux-software-drivers
F: Documentation/devicetree/bindings/iio/dac/adi,ad3552r.yaml
F: drivers/iio/dac/ad3552r.c

+ANALOG DEVICES INC AD4000 DRIVER
+M: Marcelo Schmitt <marcelo.schmitt@xxxxxxxxxx>
+L: linux-iio@xxxxxxxxxxxxxxx
+S: Supported
+W: https://ez.analog.com/linux-software-drivers
+F: Documentation/devicetree/bindings/iio/adc/adi,ad4000.yaml
+
ANALOG DEVICES INC AD4130 DRIVER
M: Cosmin Tanislav <cosmin.tanislav@xxxxxxxxxx>
L: linux-iio@xxxxxxxxxxxxxxx
--
2.43.0