On 6/18/24 6:12 PM, Marcelo Schmitt wrote: > 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 Datasheets URLs are listed in the patch, so probably don't need them in the commit message too. > > Signed-off-by: Marcelo Schmitt <marcelo.schmitt@xxxxxxxxxx> > --- > .../bindings/iio/adc/adi,ad4000.yaml | 231 ++++++++++++++++++ > MAINTAINERS | 7 + > 2 files changed, 238 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..ba50f9e0784b > --- /dev/null > +++ b/Documentation/devicetree/bindings/iio/adc/adi,ad4000.yaml > @@ -0,0 +1,231 @@ > +# 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 > + There are data sheets listed for adaq400x but no compatibles. > + 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/uint16 Any particular reason why this needs to be uint16 instead of the more common 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 > + # The configuration register can only be accessed in '3-wire' mode > + - if: > + not: > + properties: > + adi,spi-mode: > + contains: > + enum: > + - single adi,spi-mode is not an array and we are only checking for one value, so this could be simplified to: properties: adi,spi-mode: const: single > + then: > + properties: > + adi,high-z-input: false > + # 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 */ Comments are a bit redundant since it says "examples:" above and the type of the chip in the compatible string. > + 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>; > + 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>; > + adi,spi-mode = "single"; > + }; > + }; > 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
