Re: [PATCH 0/3] iio: adc: aspeed: Fix SCU lookup for multi-SCU AST2700

From: Joshua Crofts

Date: Thu Oct 01 2026 - 03:18:41 EST


On Thu, 1 Oct 2026 11:28:43 +0800
Billy Tsai <billy_tsai@xxxxxxxxxxxxxx> wrote:

> The ADC's reference-voltage trimming data lives in a SCU register. The
> driver has always located that SCU with a global, name-based
> device-tree search, which works as long as a platform only has a
> single node named "syscon". AST2700 splits its SCU into two
> instances, syscon0 and syscon1, that share that same node name and
> differ only by label and unit address, so the lookup always resolves
> to syscon0 even when the ADC's trimming data lives in syscon1.
>
> This series adds an explicit "syscon" phandle property so multi-SCU
> platforms can point the ADC at the right SCU, keeps the existing
> global lookup as a fallback for single-SCU platforms and already
> deployed device trees, and wires the new property up on AST2700.
>
> Patch summary:
> 1. dt-bindings: iio: adc: Add syscon property for multi-SCU SoCs
> 2. iio: adc: aspeed: Use syscon phandle for trimming data when available
> 3. arm64: dts: aspeed: Add syscon phandle to AST2700 ADC nodes
>
> Assisted-by: Claude:claude-sonnet-5

All Assisted-by tags in your series should be changed to "Assisted-by: LLM"

> Signed-off-by: Billy Tsai <billy_tsai@xxxxxxxxxxxxxx>
> ---
> Billy Tsai (3):
> dt-bindings: iio: adc: Add syscon property for multi-SCU SoCs
> iio: adc: aspeed: Use syscon phandle for trimming data when available
> arm64: dts: aspeed: Add syscon phandle to AST2700 ADC nodes
>
> .../bindings/iio/adc/aspeed,ast2600-adc.yaml | 28 ++++++++++++++++++++++
> arch/arm64/boot/dts/aspeed/aspeed-g7-soc1.dtsi | 2 ++
> drivers/iio/adc/aspeed_adc.c | 20 +++++++++++-----
> 3 files changed, 44 insertions(+), 6 deletions(-)
> ---
> base-commit: a3b3580713f3ac5a32dc2874ee546828977a1d68
> change-id: 20261001-ast27xx-adc-upstream-34b3d9e8e27b
>
> Best regards,



--
Kind regards,
Joshua Crofts