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+# SPDX-License-Identifier: GPL-2.0
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/iio/adc/adc.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: IIO Common Properties for ADC Channels
+
+maintainers:
+ - Jonathan Cameron <jic23@kernel.org>
+
+description:
+ A few properties are defined in a common way ADC channels.
+
+properties:
+ $nodename:
+ pattern: "^channel(@[0-9a-f]+)?$"
+ description:
+ A channel index should match reg.
+
+ reg:
+ maxItems: 1
+
+ label:
+ description: Unique name to identify which channel this is.
+
+ bipolar:
+ $ref: /schemas/types.yaml#/definitions/flag
+ description: If provided, the channel is to be used in bipolar mode.
+
+ diff-channels:
+ $ref: /schemas/types.yaml#/definitions/uint32-array
+ maxItems: 2
+ minItems: 2
+ description:
+ Many ADCs have dual Muxes to allow different input pins to be routed
+ to both the positive and negative inputs of a differential ADC.
+ The first value specifies the positive input pin, the second
+ specifies the negative input pin.
+ There are also some ADCs, where the differential channel has dedicated
+ positive and negative inputs which can be used to measure differential
+ voltage levels. For those setups, this property can be configured with
+ the 'reg' property for both inputs (i.e. diff-channels = <reg reg>).
+
+ single-channel:
+ $ref: /schemas/types.yaml#/definitions/uint32
+ description:
+ When devices combine single-ended and differential channels, allow the
+ channel for a single element to be specified, independent of reg (as for
+ differential channels). If this and diff-channels are not present reg
+ shall be used instead.
+
+ common-mode-channel:
+ $ref: /schemas/types.yaml#/definitions/uint32
+ description:
+ Some ADCs have differential input pins that can be used to measure
+ single-ended or pseudo-differential inputs. This property can be used
+ in addition to single-channel to signal software that this channel is
+ not differential but still specify two inputs.
+
+ The input pair is specified by setting single-channel to the positive
+ input pin and common-mode-channel to the negative pin.
+
+ settling-time-us:
+ description:
+ Time between enabling the channel and first stable readings.
+
+ oversampling-ratio:
+ $ref: /schemas/types.yaml#/definitions/uint32
+ description:
+ Oversampling is used as replacement of or addition to the low-pass filter.
+ In some cases, the desired filtering characteristics are a function the
+ device design and can interact with other characteristics such as
+ settling time.
+
+anyOf:
+ - oneOf:
+ - required:
+ - reg
+ - diff-channels
+ - required:
+ - reg
+ - single-channel
+ - required:
+ - reg
+
+additionalProperties: true