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:
+iio-bindings.txt for more details, but notice that this particular
+ADC has a special addressing scheme that require two cells for
+identifying each ADC channel:
-- #address-cells: should be set to <1>
+- #address-cells: should be set to <2>, the first cell is the
+ prescaler (on PM8058) or premux (on PM8921) with two valid bits
+ so legal values are 0x00, 0x01 or 0x02. The second cell
+ is the main analog mux setting (0x00..0x0f). The combination
+ of prescaler/premux and analog mux uniquely addresses a hardware
+ channel on all systems.
- #size-cells: should be set to <0>
-- #io-channel-cells: should be set to <1>
+- #io-channel-cells: should be set to <2>, again the cells are
+ precaler or premux followed by the analog muxing line.
- 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:
+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>;
+ reg = <0x00 0x0c>;
};
adc-channel@d {
- reg = <0x0d>;
+ reg = <0x00 0x0d>;
};
adc-channel@f {
- reg = <0x0f>;
+ reg = <0x00 0x0f>;
};
These three nodes are used for absolute and ratiometric calibration
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.
+Optional subnodes: any channels other than channels [0x00 0x0c],
+[0x00 0x0d] and [0x00 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.
+ 0 .. 0xff (8 bits).
Optional channel node properties:
xoadc: xoadc@197 {
compatible = "qcom,pm8058-adc";
reg = <0x197>;
- interrupt-parent = <&pm8058>;
- interrupts = <76 1>;
- #address-cells = <1>;
+ interrupts-extended = <&pm8058 76 IRQ_TYPE_EDGE_RISING>;
+ #address-cells = <2>;
#size-cells = <0>;
- #io-channel-cells = <1>;
+ #io-channel-cells = <2>;
vcoin: adc-channel@0 {
- reg = <0x00>;
+ reg = <0x00 0x00>;
};
vbat: adc-channel@1 {
- reg = <0x01>;
+ reg = <0x00 0x01>;
};
dcin: adc-channel@2 {
- reg = <0x02>;
+ reg = <0x00 0x02>;
};
ichg: adc-channel@3 {
- reg = <0x03>;
+ reg = <0x00 0x03>;
};
vph_pwr: adc-channel@4 {
- reg = <0x04>;
+ reg = <0x00 0x04>;
};
usb_vbus: adc-channel@a {
- reg = <0x0a>;
+ reg = <0x00 0x0a>;
};
die_temp: adc-channel@b {
- reg = <0x0b>;
+ reg = <0x00 0x0b>;
};
ref_625mv: adc-channel@c {
- reg = <0x0c>;
+ reg = <0x00 0x0c>;
};
ref_1250mv: adc-channel@d {
- reg = <0x0d>;
+ reg = <0x00 0x0d>;
};
ref_325mv: adc-channel@e {
- reg = <0x0e>;
+ reg = <0x00 0x0e>;
};
ref_muxoff: adc-channel@f {
- reg = <0x0f>;
+ reg = <0x00 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 */
+ io-channels = <&xoadc 0x00 0x01>, /* Battery */
+ <&xoadc 0x00 0x02>, /* DC in (charger) */
+ <&xoadc 0x00 0x04>, /* VPH the main system voltage */
+ <&xoadc 0x00 0x0b>, /* Die temperature */
+ <&xoadc 0x00 0x0c>, /* Reference voltage 1.25V */
+ <&xoadc 0x00 0x0d>, /* Reference voltage 0.625V */
+ <&xoadc 0x00 0x0e>; /* Reference voltage 0.325V */
};