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diff --git a/Documentation/devicetree/bindings/iio/adc/qcom,pm8xxx-xoadc.txt b/Documentation/devicetree/bindings/iio/adc/qcom,pm8xxx-xoadc.txt
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+Qualcomm's PM8xxx voltage XOADC
+
+The Qualcomm PM8xxx PMICs contain a HK/XO ADC (Housekeeping/Crystal
+oscillator ADC) encompassing PM8018, PM8038, PM8058 and PM8921.
+
+Required properties:
+
+- compatible: should be one of:
+  "qcom,pm8018-adc"
+  "qcom,pm8038-adc"
+  "qcom,pm8058-adc"
+  "qcom,pm8921-adc"
+
+- reg: should contain the ADC base address in the PMIC, typically
+  0x197.
+
+- xoadc-ref-supply: should reference a regulator that can supply
+  a reference voltage on demand. The reference voltage may vary
+  with PMIC variant but is typically something like 2.2 or 1.8V.
+
+The following required properties are standard for IO channels, see
+iio-bindings.txt for more details:
+
+- #address-cells: should be set to <1>
+
+- #size-cells: should be set to <0>
+
+- #io-channel-cells: should be set to <1>
+
+- interrupts: should refer to the parent PMIC interrupt controller
+  and reference the proper ADC interrupt.
+
+Required subnodes:
+
+The ADC channels are configured as subnodes of the ADC. Since some of
+them are used for calibrating the ADC, these nodes are compulsory:
+
+adc-channel@c {
+	reg = <0x0c>;
+};
+
+adc-channel@d {
+	reg = <0x0d>;
+};
+
+adc-channel@f {
+	reg = <0x0f>;
+};
+
+These three nodes are used for absolute and ratiometric calibration
+and only need to have these reg values: they are by hardware definition
+1:1 ratio converters that sample 625, 1250 and 0 milliV and create
+an interpolation calibration for all other ADCs.
+
+Optional subnodes: any channels other than channel 0x0c, 0x0d and
+0x0f are optional.
+
+Required channel node properties:
+
+- reg: should contain the hardware channel number in the range
+  0 .. 0x0f (4 bits). The hardware only supports 16 channels.
+
+Optional channel node properties:
+
+- qcom,decimation:
+  Value type: <u32>
+  Definition: This parameter is used to decrease the ADC sampling rate.
+          Quicker measurements can be made by reducing the decimation ratio.
+          Valid values are 512, 1024, 2048, 4096.
+          If the property is not found, a default value of 512 will be used.
+
+- qcom,ratiometric:
+  Value type: <u32>
+  Definition: Channel calibration type. If this property is specified
+          VADC will use a special voltage references for channel
+          calibration. The available references are specified in the
+	  as a u32 value setting (see below) and it is compulsory
+	  to also specify this reference if ratiometric calibration
+	  is selected.
+
+	  If the property is not found, the channel will be
+          calibrated with the 0.625V and 1.25V reference channels, also
+          known as an absolute calibration.
+  The reference voltage pairs when using ratiometric calibration:
+	  0 = XO_IN/XOADC_GND
+	  1 = PMIC_IN/XOADC_GND
+	  2 = PMIC_IN/BMS_CSP
+	  3 (invalid)
+	  4 = XOADC_GND/XOADC_GND
+	  5 = XOADC_VREF/XOADC_GND
+
+Example:
+
+xoadc: xoadc@197 {
+	compatible = "qcom,pm8058-adc";
+	reg = <0x197>;
+	interrupt-parent = <&pm8058>;
+	interrupts = <76 1>;
+	#address-cells = <1>;
+	#size-cells = <0>;
+	#io-channel-cells = <1>;
+
+	vcoin: adc-channel@0 {
+		reg = <0x00>;
+	};
+	vbat: adc-channel@1 {
+		reg = <0x01>;
+	};
+	dcin: adc-channel@2 {
+		reg = <0x02>;
+	};
+	ichg: adc-channel@3 {
+		reg = <0x03>;
+	};
+	vph_pwr: adc-channel@4 {
+		reg = <0x04>;
+	};
+	usb_vbus: adc-channel@a {
+		reg = <0x0a>;
+	};
+	die_temp: adc-channel@b {
+		reg = <0x0b>;
+	};
+	ref_625mv: adc-channel@c {
+		reg = <0x0c>;
+	};
+	ref_1250mv: adc-channel@d {
+		reg = <0x0d>;
+	};
+	ref_325mv: adc-channel@e {
+		reg = <0x0e>;
+	};
+	ref_muxoff: adc-channel@f {
+		reg = <0x0f>;
+	};
+};
+
+
+/* IIO client node */
+iio-hwmon {
+	compatible = "iio-hwmon";
+	io-channels = <&xoadc 0x01>, /* Battery */
+		    <&xoadc 0x02>, /* DC in (charger) */
+		    <&xoadc 0x04>, /* VPH the main system voltage */
+		    <&xoadc 0x0b>, /* Die temperature */
+		    <&xoadc 0x0c>, /* Reference voltage 1.25V */
+		    <&xoadc 0x0d>, /* Reference voltage 0.625V */
+		    <&xoadc 0x0e>; /* Reference voltage 0.325V */
+};