[PATCH v4] arm64: dts: aspeed: Add syscon phandle to AST2700 ADC nodes

[PATCH v4] arm64: dts: aspeed: Add syscon phandle to AST2700 ADC nodes

[Billy Tsai]

Point the ADC nodes at their own syscon1 so the driver can correctly
locate the reference-voltage trimming data on AST2700, where syscon0
and syscon1 share the same device-tree node name and would otherwise
resolve to the wrong SCU.

Fixes: e77bb5dc5759 ("arm64: dts: aspeed: Add initial AST27xx SoC device tree")
Assisted-by: LLM
Signed-off-by: Billy Tsai <billy_tsai@aspeedtech.com>
---
This was patch 3/3 of "iio: adc: aspeed: Fix SCU lookup for multi-SCU
AST2700" (https://lore.kernel.org/r/20261005-ast27xx-adc-upstream-v3-0-ef25552d3a59@aspeedtech.com).
Jonathan has applied patches 1 and 2 to the testing branch of iio.git;
this resends patch 3 on its own, now with a Fixes tag, since the
driver falls back to the old global syscon lookup whenever this
property is absent, so patches 1 and 2 alone don't change AST2700's
behaviour without it.
---
 arch/arm64/boot/dts/aspeed/aspeed-g7-soc1.dtsi | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/arch/arm64/boot/dts/aspeed/aspeed-g7-soc1.dtsi b/arch/arm64/boot/dts/aspeed/aspeed-g7-soc1.dtsi
index bc990f79e693..053673cc4b8e 100644
--- a/arch/arm64/boot/dts/aspeed/aspeed-g7-soc1.dtsi
+++ b/arch/arm64/boot/dts/aspeed/aspeed-g7-soc1.dtsi
@@ -246,6 +246,7 @@ adc0: adc@14c00000 {
 		clocks = <&syscon1 SCU1_CLK_AHB>;
 		resets = <&syscon1 SCU1_RESET_ADC>;
 		interrupts-extended = <&intc1 80>;
+		aspeed,trim-syscon = <&syscon1>;
 		#io-channel-cells = <1>;
 		status = "disabled";
 	};
@@ -256,6 +257,7 @@ adc1: adc@14c00100 {
 		clocks = <&syscon1 SCU1_CLK_AHB>;
 		resets = <&syscon1 SCU1_RESET_ADC>;
 		interrupts-extended = <&intc1 80>;
+		aspeed,trim-syscon = <&syscon1>;
 		#io-channel-cells = <1>;
 		status = "disabled";
 	};

---
base-commit: 43ffda3c7f8456bbe641ae8249a077a361b97880
change-id: 20261021-ast27xx-adc-dts-syscon-9cf5d733ed0e

Best regards,
-- 
Billy Tsai <billy_tsai@aspeedtech.com>

Re: [PATCH v4] arm64: dts: aspeed: Add syscon phandle to AST2700 ADC nodes

[Jonathan Cameron]

On Wed, 21 Oct 2026 10:09:39 +0800
Billy Tsai <billy_tsai@aspeedtech.com> wrote:

> Point the ADC nodes at their own syscon1 so the driver can correctly
> locate the reference-voltage trimming data on AST2700, where syscon0
> and syscon1 share the same device-tree node name and would otherwise
> resolve to the wrong SCU.
> 
> Fixes: e77bb5dc5759 ("arm64: dts: aspeed: Add initial AST27xx SoC device tree")
> Assisted-by: LLM
> Signed-off-by: Billy Tsai <billy_tsai@aspeedtech.com>
> ---
> This was patch 3/3 of "iio: adc: aspeed: Fix SCU lookup for multi-SCU
> AST2700" (https://lore.kernel.org/r/20261005-ast27xx-adc-upstream-v3-0-ef25552d3a59@aspeedtech.com).
> Jonathan has applied patches 1 and 2 to the testing branch of iio.git;
> this resends patch 3 on its own, now with a Fixes tag, since the
> driver falls back to the old global syscon lookup whenever this
> property is absent, so patches 1 and 2 alone don't change AST2700's
> behaviour without it.

I've now moved these at Billy's request to the fixes-togreg branch
and tagged them for stable. That will go upstream sometime after
rc1 (rather than waiting for the next cycle as testing would have
done).

Thanks,

Jonathan

> ---
>  arch/arm64/boot/dts/aspeed/aspeed-g7-soc1.dtsi | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/arch/arm64/boot/dts/aspeed/aspeed-g7-soc1.dtsi b/arch/arm64/boot/dts/aspeed/aspeed-g7-soc1.dtsi
> index bc990f79e693..053673cc4b8e 100644
> --- a/arch/arm64/boot/dts/aspeed/aspeed-g7-soc1.dtsi
> +++ b/arch/arm64/boot/dts/aspeed/aspeed-g7-soc1.dtsi
> @@ -246,6 +246,7 @@ adc0: adc@14c00000 {
>  		clocks = <&syscon1 SCU1_CLK_AHB>;
>  		resets = <&syscon1 SCU1_RESET_ADC>;
>  		interrupts-extended = <&intc1 80>;
> +		aspeed,trim-syscon = <&syscon1>;
>  		#io-channel-cells = <1>;
>  		status = "disabled";
>  	};
> @@ -256,6 +257,7 @@ adc1: adc@14c00100 {
>  		clocks = <&syscon1 SCU1_CLK_AHB>;
>  		resets = <&syscon1 SCU1_RESET_ADC>;
>  		interrupts-extended = <&intc1 80>;
> +		aspeed,trim-syscon = <&syscon1>;
>  		#io-channel-cells = <1>;
>  		status = "disabled";
>  	};
> 
> ---
> base-commit: 43ffda3c7f8456bbe641ae8249a077a361b97880
> change-id: 20261021-ast27xx-adc-dts-syscon-9cf5d733ed0e
> 
> Best regards,