[PATCH v2 2/5] ARM: dts: add reference voltage property for MXS LRADC
From: Hector Palacios
Date: Fri Jul 19 2013 - 05:14:19 EST
Some LRADC channels have fixed pre-dividers so they can measure
different voltages at full scale. The reference voltage allows to
expose a scaling attribute through the IIO sysfs so that a user can
compute the real voltage out of a measured sample value.
Signed-off-by: Hector Palacios <hector.palacios@xxxxxxxx>
---
Documentation/devicetree/bindings/staging/iio/adc/mxs-lradc.txt | 9 ++++++++-
arch/arm/boot/dts/imx23.dtsi | 4 ++++
arch/arm/boot/dts/imx28.dtsi | 4 ++++
3 files changed, 16 insertions(+), 1 deletion(-)
diff --git a/Documentation/devicetree/bindings/staging/iio/adc/mxs-lradc.txt b/Documentation/devicetree/bindings/staging/iio/adc/mxs-lradc.txt
index 4688205..6ec485c 100644
--- a/Documentation/devicetree/bindings/staging/iio/adc/mxs-lradc.txt
+++ b/Documentation/devicetree/bindings/staging/iio/adc/mxs-lradc.txt
@@ -1,9 +1,12 @@
* Freescale i.MX28 LRADC device driver
Required properties:
-- compatible: Should be "fsl,imx28-lradc"
+- compatible: "fsl,imx28-lradc", "fsl,imx23-lradc"
- reg: Address and length of the register set for the device
- interrupts: Should contain the LRADC interrupts
+- fsl,vref: Reference voltage (in mV) for each LRADC channel. This is the
+ maximum voltage that can be measured at full scale in each channel
+ considering fixed pre-dividers.
Optional properties:
- fsl,lradc-touchscreen-wires: Number of wires used to connect the touchscreen
@@ -18,4 +21,8 @@ Examples:
reg = <0x80050000 0x2000>;
interrupts = <10 14 15 16 17 18 19
20 21 22 23 24 25>;
+ fsl,vref = <1850 1850 1850 1850
+ 1850 1850 1850 7400
+ 1850 1850 3700 1850
+ 3700 1850 1850 7400>
};
diff --git a/arch/arm/boot/dts/imx23.dtsi b/arch/arm/boot/dts/imx23.dtsi
index 587ceef..e212902 100644
--- a/arch/arm/boot/dts/imx23.dtsi
+++ b/arch/arm/boot/dts/imx23.dtsi
@@ -430,6 +430,10 @@
compatible = "fsl,imx23-lradc";
reg = <0x80050000 0x2000>;
interrupts = <36 37 38 39 40 41 42 43 44>;
+ fsl,vref = <1850 1850 1850 1850
+ 1850 1850 3700 7400
+ 1850 1850 1850 1850
+ 1850 1850 1850 7400>;
status = "disabled";
};
diff --git a/arch/arm/boot/dts/imx28.dtsi b/arch/arm/boot/dts/imx28.dtsi
index 6a8acb0..c1b3724 100644
--- a/arch/arm/boot/dts/imx28.dtsi
+++ b/arch/arm/boot/dts/imx28.dtsi
@@ -865,6 +865,10 @@
reg = <0x80050000 0x2000>;
interrupts = <10 14 15 16 17 18 19
20 21 22 23 24 25>;
+ fsl,vref = <1850 1850 1850 1850
+ 1850 1850 1850 7400
+ 1850 1850 3700 1850
+ 3700 1850 1850 7400>;
status = "disabled";
};
--
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