[PATCH v2] ARM: dts: bcm2711-rpi-cm4-io: Add rtc on a pinctrl-muxed i2c bus

Uwe Kleine-König u.kleine-koenig at pengutronix.de
Thu Dec 9 10:18:13 PST 2021


From: Uwe Kleine-König <uwe at kleine-koenig.org>

The cm4-io board comes with an PCF85063. Add it to the device tree to make
it usable. The i2c0 bus can use two different pinmux settings to use
different pins. To keep the bus appearing on the usual pin pair (gpio0 +
gpio1) use a pinctrl-muxed setting as the upstream dts does.

Signed-off-by: Uwe Kleine-König <uwe at kleine-koenig.org>
---
 arch/arm/boot/dts/bcm2711-rpi-cm4-io.dts | 35 ++++++++++++++++++++++++
 1 file changed, 35 insertions(+)

diff --git a/arch/arm/boot/dts/bcm2711-rpi-cm4-io.dts b/arch/arm/boot/dts/bcm2711-rpi-cm4-io.dts
index 19600b629be5..5ddad146b541 100644
--- a/arch/arm/boot/dts/bcm2711-rpi-cm4-io.dts
+++ b/arch/arm/boot/dts/bcm2711-rpi-cm4-io.dts
@@ -18,6 +18,41 @@ led-pwr {
 			linux,default-trigger = "default-on";
 		};
 	};
+
+	i2c0mux {
+		compatible = "i2c-mux-pinctrl";
+		#address-cells = <1>;
+		#size-cells = <0>;
+
+		i2c-parent = <&i2c0>;
+
+		pinctrl-names = "i2c0", "i2c0-vc";
+		pinctrl-0 = <&i2c0_gpio0>;
+		pinctrl-1 = <&i2c0_gpio44>;
+
+		i2c at 0 {
+			reg = <0>;
+			#address-cells = <1>;
+			#size-cells = <0>;
+		};
+
+		i2c at 1 {
+			reg = <1>;
+			#address-cells = <1>;
+			#size-cells = <0>;
+
+			rtc at 51 {
+				/* Attention: An alarm resets the machine */
+				compatible = "nxp,pcf85063";
+				reg = <0x51>;
+			};
+		};
+	};
+};
+
+&i2c0 {
+	/delete-property/ pinctrl-names;
+	/delete-property/ pinctrl-0;
 };
 
 &ddc0 {

base-commit: 0fcfb00b28c0b7884635dacf38e46d60bf3d4eb1
-- 
2.30.2




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