[PATCH 4/8] ARM: dts: stm32: enable adc on stm32mp15xx-dkx boards

Olivier Moysan olivier.moysan at foss.st.com
Wed May 24 06:39:13 PDT 2023


U-Boot enables ADC1&2 to support USB power measurement and ADC
calibration on STM32MP15x Disco boards.
When leaving U-boot the ADCs do not return to power down state
to keep ADC linear calibration available for kernel.
Enable ADC1&2 by default on STM32MP15xx-DKx boards to align kernel
DT with Uboot. This avoids to shutdown the ADCs VDDA, while the
ADCs are not in power down.

Use STM32 ADC generic bindings instead of legacy bindings on
STM32MP15xx-DKx boards.

The ADC pins on Arduino connector are not set by default.
These pins are added in A7 Disco example DTs only.

Signed-off-by: Olivier Moysan <olivier.moysan at foss.st.com>
---
 arch/arm/boot/dts/stm32mp15xx-dkx.dtsi | 29 ++++++++++++++++++--------
 1 file changed, 20 insertions(+), 9 deletions(-)

diff --git a/arch/arm/boot/dts/stm32mp15xx-dkx.dtsi b/arch/arm/boot/dts/stm32mp15xx-dkx.dtsi
index 0f1110e42c93..ad46f1b1e1ed 100644
--- a/arch/arm/boot/dts/stm32mp15xx-dkx.dtsi
+++ b/arch/arm/boot/dts/stm32mp15xx-dkx.dtsi
@@ -93,28 +93,39 @@ vin: vin {
 
 &adc {
 	pinctrl-names = "default";
-	pinctrl-0 = <&adc12_ain_pins_a>, <&adc12_usb_cc_pins_a>;
+	pinctrl-0 = <&adc12_usb_cc_pins_a>;
 	vdd-supply = <&vdd>;
 	vdda-supply = <&vdd>;
 	vref-supply = <&vrefbuf>;
-	status = "disabled";
+	status = "okay";
 	adc1: adc at 0 {
+		status = "okay";
 		/*
 		 * Type-C USB_PWR_CC1 & USB_PWR_CC2 on in18 & in19.
 		 * Use at least 5 * RC time, e.g. 5 * (Rp + Rd) * C:
 		 * 5 * (56 + 47kOhms) * 5pF => 2.5us.
 		 * Use arbitrary margin here (e.g. 5us).
 		 */
-		st,min-sample-time-nsecs = <5000>;
-		/* AIN connector, USB Type-C CC1 & CC2 */
-		st,adc-channels = <0 1 6 13 18 19>;
-		status = "okay";
+		channel at 18 {
+			reg = <18>;
+			st,min-sample-time-ns = <5000>;
+		};
+		channel at 19 {
+			reg = <19>;
+			st,min-sample-time-ns = <5000>;
+		};
 	};
 	adc2: adc at 100 {
-		/* AIN connector, USB Type-C CC1 & CC2 */
-		st,adc-channels = <0 1 2 6 18 19>;
-		st,min-sample-time-nsecs = <5000>;
 		status = "okay";
+		/* USB Type-C CC1 & CC2 */
+		channel at 18 {
+			reg = <18>;
+			st,min-sample-time-ns = <5000>;
+		};
+		channel at 19 {
+			reg = <19>;
+			st,min-sample-time-ns = <5000>;
+		};
 	};
 };
 
-- 
2.25.1




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