This adds a new binding for the Analog Devices, Inc. AD7944, AD7985, and AD7986 ADCs. Signed-off-by: David Lechner <dlechner@xxxxxxxxxxxx> --- .../devicetree/bindings/iio/adc/adi,ad7944.yaml | 231 +++++++++++++++++++++ MAINTAINERS | 8 + 2 files changed, 239 insertions(+) diff --git a/Documentation/devicetree/bindings/iio/adc/adi,ad7944.yaml b/Documentation/devicetree/bindings/iio/adc/adi,ad7944.yaml new file mode 100644 index 000000000000..a023adbeba42 --- /dev/null +++ b/Documentation/devicetree/bindings/iio/adc/adi,ad7944.yaml @@ -0,0 +1,231 @@ +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/iio/adc/adi,ad7944.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: Analog Devices PulSAR LFCSP Analog to Digital Converters + +maintainers: + - Michael Hennerich <Michael.Hennerich@xxxxxxxxxx> + - Nuno Sá <nuno.sa@xxxxxxxxxx> + +description: | + A family of pin-compatible single channel differential analog to digital + converters with SPI support in a LFCSP package. + + * https://www.analog.com/en/products/ad7944.html + * https://www.analog.com/en/products/ad7985.html + * https://www.analog.com/en/products/ad7986.html + +$ref: /schemas/spi/spi-peripheral-props.yaml# + +properties: + compatible: + enum: + - adi,ad7944 + - adi,ad7985 + - adi,ad7986 + + reg: + maxItems: 1 + + spi-max-frequency: + maximum: 111111111 + + spi-cpha: true + + adi,spi-mode: + $ref: /schemas/types.yaml#/definitions/string + enum: [ 3-wire, 4-wire, chain ] + default: 4-wire + description: + This chip can operate in a 3-wire mode where SDI is tied to VIO, a 4-wire + mode where SDI acts as the CS line, or a chain mode where SDI 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. + + avdd-supply: + description: A 2.5V supply that powers the analog circuitry. + + dvdd-supply: + description: A 2.5V supply that powers the digital circuitry. + + vio-supply: + description: + A 1.8V to 2.7V supply for the digital inputs and outputs. + + bvdd-supply: + description: + A voltage supply for the buffered power. When using an external reference + without an internal buffer (PDREF high, REFIN low), this should be + connected to the same supply as ref-supply. Otherwise, when using an + internal reference or an external reference with an internal buffer, this + is connected to a 5V supply. + + ref-supply: + description: + Voltage regulator for the reference voltage (REF). This property is + omitted when using an internal reference. + + refin-supply: + description: + Voltage regulator for the reference buffer input (REFIN). When using an + external buffer with internal reference, this should be connected to a + 1.2V external reference voltage supply. + + adi,reference: + $ref: /schemas/types.yaml#/definitions/string + enum: [ internal, internal-buffer, external ] + default: internal + description: | + This property is used to specify the reference voltage source. + + * internal: PDREF is wired low. The internal 4.096V reference voltage is + used. The REF pin outputs 4.096V and REFIN outputs 1.2V. + * internal-buffer: PDREF is wired high. REFIN is supplied with 1.2V. The + buffered internal 4.096V reference voltage is used. The REF pin outputs + 4.096V. + * external: PDREF is wired high and REFIN is wired low. The supply + connnected the REF pin is used as the reference voltage. + + 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 + 3-wire mode, this property is omitted if the CNV pin is connected to the + CS line of the SPI controller. + maxItems: 1 + + turbo-gpios: + description: + GPIO connected to the TURBO line. If omitted, it is assumed that the TURBO + line is hard-wired and the state is determined by the adi,always-turbo + property. + maxItems: 1 + + adi,always-turbo: + type: boolean + description: + When present, this property indicates that the TURBO line is hard-wired + and the state is always high. If neither this property nor turbo-gpios is + present, the TURBO line is assumed to be hard-wired and the state is + always low. + + 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 + - avdd-supply + - dvdd-supply + - vio-supply + - bvdd-supply + +allOf: + # ref-supply is only used for external reference voltage + - if: + not: + required: + - adi,reference + then: + properties: + ref-supply: false + else: + if: + properties: + adi,reference: + const: external + then: + required: + - ref-supply + else: + properties: + ref-supply: false + # refin-supply is only used for internal buffer reference voltage + - if: + not: + required: + - adi,reference + then: + properties: + refin-supply: false + else: + if: + properties: + adi,reference: + const: internal-buffer + then: + required: + - refin-supply + else: + properties: + refin-supply: false + # in 3-wire mode, cnv-gpios is optional, for other modes it is required + - if: + not: + required: + - adi,spi-mode + then: + required: + - cnv-gpios + else: + if: + properties: + adi,spi-mode: + enum: [ 4-wire, chain ] + then: + required: + - cnv-gpios + # chain mode doesn't work when TRUBO is enabled + - if: + properties: + adi,spi-mode: + const: chain + required: + - adi,spi-mode + then: + properties: + adi,always-turbo: false + # turbo-gpios and adi,always-turbo are mutually exclusive + - if: + required: + - turbo-gpios + then: + properties: + adi,always-turbo: false + - if: + required: + - adi,always-turbo + then: + properties: + turbo-gpios: false + +unevaluatedProperties: false + +examples: + - | + #include <dt-bindings/gpio/gpio.h> + spi { + #address-cells = <1>; + #size-cells = <0>; + adc@0 { + compatible = "adi,ad7944"; + reg = <0>; + spi-cpha; + spi-max-frequency = <111111111>; + avdd-supply = <&supply_2_5V>; + dvdd-supply = <&supply_2_5V>; + vio-supply = <&supply_1_8V>; + bvdd-supply = <&supply_5V>; + cnv-gpios = <&gpio 0 GPIO_ACTIVE_HIGH>; + turbo-gpios = <&gpio 1 GPIO_ACTIVE_HIGH>; + }; + }; diff --git a/MAINTAINERS b/MAINTAINERS index 00d354af10f5..4f1e658e1e0d 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -451,6 +451,14 @@ W: http://wiki.analog.com/AD7879 W: https://ez.analog.com/linux-software-drivers F: drivers/input/touchscreen/ad7879.c +AD7944 ADC DRIVER (AD7944/AD7985/AD7986) +M: Michael Hennerich <michael.hennerich@xxxxxxxxxx> +M: Nuno Sá <nuno.sa@xxxxxxxxxx> +R: David Lechner <dlechner@xxxxxxxxxxxx> +S: Supported +W: https://ez.analog.com/linux-software-drivers +F: Documentation/devicetree/bindings/iio/adc/adi,ad7944.yaml + ADAFRUIT MINI I2C GAMEPAD M: Anshul Dalal <anshulusr@xxxxxxxxx> L: linux-input@xxxxxxxxxxxxxxx -- 2.43.0