From: Sven Peter <sven@kernel.org>

The System Manager Controller of all M1/M2 SoCs supports the RTC
sub-device.

Reviewed-by: Neal Gompa <neal@gompa.dev>
Signed-off-by: Sven Peter <sven@kernel.org>
Signed-off-by: James Calligeros <jcalligeros99@gmail.com>
---
 .../arm64/boot/dts/apple/t600x-die0.dtsi | 6 ++++++
 arch/arm64/boot/dts/apple/t8103.dtsi     | 6 ++++++
 arch/arm64/boot/dts/apple/t8112.dtsi     | 6 ++++++
 3 files changed, 18 insertions(+)

diff --git a/arch/arm64/boot/dts/apple/t600x-die0.dtsi b/arch/arm64/boot/dts/apple/t600x-die0.dtsi
index 3603b276a2abcfa6a730f58d5c6b9914f22f00b0..f715b19efd1679e5cd384a967d6e2a7c261ee679 100644
--- a/arch/arm64/boot/dts/apple/t600x-die0.dtsi
+++ b/arch/arm64/boot/dts/apple/t600x-die0.dtsi
@@ -44,6 +44,12 @@ smc_reboot: reboot {
 			nvmem-cell-names = "shutdown_flag", "boot_stage",
 				"boot_error_count", "panic_count";
 		};
+
+		rtc {
+			compatible = "apple,smc-rtc";
+			nvmem-cells = <&rtc_offset>;
+			nvmem-cell-names = "rtc_offset";
+		};
 	};
 
 	smc_mbox: mbox@290408000 {
diff --git a/arch/arm64/boot/dts/apple/t8103.dtsi b/arch/arm64/boot/dts/apple/t8103.dtsi
index 8b7b27887968741b745651e5133dffa7d8d20f6d..59f2678639cf47f469dc699c0ecb5b9e50a45ab1 100644
--- a/arch/arm64/boot/dts/apple/t8103.dtsi
+++ b/arch/arm64/boot/dts/apple/t8103.dtsi
@@ -916,6 +916,12 @@ smc_reboot: reboot {
 				nvmem-cell-names = "shutdown_flag", "boot_stage",
 					"boot_error_count", "panic_count";
 			};
+
+			rtc {
+				compatible = "apple,smc-rtc";
+				nvmem-cells = <&rtc_offset>;
+				nvmem-cell-names = "rtc_offset";
+			};
 		};
 
 		smc_mbox: mbox@23e408000 {
diff --git a/arch/arm64/boot/dts/apple/t8112.dtsi b/arch/arm64/boot/dts/apple/t8112.dtsi
index 3f79878b25af1f7760088aa552589494d67347fb..6bc3f58b06f703ed79578e89a030929a18d57796 100644
--- a/arch/arm64/boot/dts/apple/t8112.dtsi
+++ b/arch/arm64/boot/dts/apple/t8112.dtsi
@@ -919,6 +919,12 @@ smc_reboot: reboot {
 				nvmem-cell-names = "shutdown_flag", "boot_stage",
 					"boot_error_count", "panic_count";
 			};
+
+			rtc {
+				compatible = "apple,smc-rtc";
+				nvmem-cells = <&rtc_offset>;
+				nvmem-cell-names = "rtc_offset";
+			};
 		};
 
 		smc_mbox: mbox@23e408000 {

-- 
2.51.0