Add device tree documentation for AD4000 series of ADC devices. Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/ad4000-4004-4008.pdf Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/ad4001-4005.pdf Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/ad4002-4006-4010.pdf Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/ad4003-4007-4011.pdf Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/ad4020-4021-4022.pdf Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/adaq4001.pdf Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/adaq4003.pdf Suggested-by: David Lechner <dlechner@xxxxxxxxxxxx> Signed-off-by: Marcelo Schmitt <marcelo.schmitt@xxxxxxxxxx> --- Even though didn't pick all suggestions to the dt-bindings, I did pick most them so kept David's Suggested-by tag. .../bindings/iio/adc/adi,ad4000.yaml | 207 ++++++++++++++++++ MAINTAINERS | 7 + 2 files changed, 214 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..7470d386906b --- /dev/null +++ b/Documentation/devicetree/bindings/iio/adc/adi,ad4000.yaml @@ -0,0 +1,207 @@ +# 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: + enum: + - adi,ad4000 + - adi,ad4001 + - adi,ad4002 + - adi,ad4003 + - adi,ad4004 + - adi,ad4005 + - adi,ad4006 + - adi,ad4007 + - adi,ad4008 + - adi,ad4010 + - adi,ad4011 + - adi,ad4020 + - adi,ad4021 + - adi,ad4022 + - adi,adaq4001 + - adi,adaq4003 + + reg: + maxItems: 1 + + spi-max-frequency: + maximum: 102040816 # for VIO > 2.7 V, 81300813 for VIO > 1.7 V + + adi,spi-mode: + $ref: /schemas/types.yaml#/definitions/string + enum: [ single, chain ] + description: | + This property indicates the SPI wiring configuration. + + When this property is omitted, it is assumed that the device is using what + the datasheet calls "4-wire mode". This is the conventional SPI mode used + when there are multiple devices on the same bus. In this mode, the CNV + line is used to initiate the conversion and the SDI line is connected to + CS on the SPI controller. + + When this property is present, it indicates that the device is using one + of the following alternative wiring configurations: + + * single: The datasheet calls this "3-wire mode". (NOTE: The datasheet's + definition of 3-wire mode is NOT at all related to the standard + spi-3wire property!) This mode is often used when the ADC is the only + device on the bus. In this mode, SDI is connected to MOSI or to VIO, and + the CNV line can be connected to the CS line of the SPI controller or to + a GPIO, in which case the CS line of the controller is unused. + * chain: The datasheet calls this "chain mode". This mode is used to save + on wiring when multiple ADCs are used. In this mode, the SDI line of + one chip is tied to the SDO of the next chip in the chain and the SDI of + the last chip in the chain is tied to GND. Only the first chip in the + chain is connected to the SPI bus. The CNV line of all chips are tied + together. The CS line of the SPI controller can be used as the CNV line + only if it is active high. + + '#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: + The Convert Input (CNV). This input has multiple functions. It initiates + the conversions and selects the SPI mode of the device (chain or CS). In + 'single' mode, this property is omitted if the CNV pin is connected to the + CS line of the SPI controller. + 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/uint32 + 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 ('single' mode) or the + SDI line is low and the CNV line is high ('multi' 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: + # in '4-wire' mode, cnv-gpios is required, for other modes it is optional + - if: + not: + required: + - adi,spi-mode + then: + required: + - cnv-gpios + # chain mode has lower SCLK max rate + - if: + required: + - adi,spi-mode + properties: + adi,spi-mode: + const: chain + then: + properties: + spi-max-frequency: + maximum: 50000000 # for VIO > 2.7 V, 40000000 for VIO > 1.7 V + required: + - '#daisy-chained-devices' + else: + properties: + '#daisy-chained-devices': false + # 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>; + /* Example for a AD devices */ + 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>; + cnv-gpios = <&gpio0 88 GPIO_ACTIVE_HIGH>; + }; + }; + - | + spi { + #address-cells = <1>; + #size-cells = <0>; + /* Example for a ADAQ devices */ + adc@0 { + compatible = "adi,adaq4003"; + reg = <0>; + adi,spi-mode = "single"; + 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 = <454>; + }; + }; diff --git a/MAINTAINERS b/MAINTAINERS index bff979a507ba..1f052b9cd912 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -1200,6 +1200,13 @@ 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
