Re: [PATCH 01/10] dt-bindings: clock: renesas,r8a78000-cpg: Add CPG_SGD4_VIO_DP_{TX,OTHER}

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Medium] abi: preliminary dt-bindings cause future ABI instability
--

commit db1a73966fe6909e57fbbac33c8b7f551e07a1fb
Author: Paul Elder <paul.elder+renesas@ideasonboard.com>

dt-bindings: clock: renesas,r8a78000-cpg: Add CPG_SGD4_VIO_DP_{TX,OTHER}

This commit adds preliminary clock definitions for CPG_SGD4_VIO_DP_TX and
CPG_SGD4_VIO_DP_OTHER to the r8a78000-cpg device tree bindings for testing
purposes.

> diff --git a/include/dt-bindings/clock/renesas,r8a78000-cpg.h b/include/dt-bindings/clock/renesas,r8a78000-cpg.h
> index 5851a29847f96..8c1a01e28ddbb 100644
> --- a/include/dt-bindings/clock/renesas,r8a78000-cpg.h
> +++ b/include/dt-bindings/clock/renesas,r8a78000-cpg.h
> @@ -12,5 +12,7 @@
>  #define R8A78000_CPG_SGASYNCD16_PERW_BUS	2
>  #define R8A78000_CPG_S0D4_PERE_MAIN		3	// FIXME Preliminary
>  #define R8A78000_CPG_MSOCK_PERW_BUS		4	// FIXME Preliminary
> +#define R8A78000_CPG_SGD4_VIO_DP_TX		5	// FIXME Preliminary
> +#define R8A78000_CPG_SGD4_VIO_DP_OTHER		6	// FIXME Preliminary

[Severity: Medium]
Does introducing these explicitly preliminary clock indices into the device
tree bindings header create a risk for future ABI breakage?

Device tree bindings typically define a stable ABI between the hardware
description and the operating system kernel. If R8A78000_CPG_SGD4_VIO_DP_TX
or R8A78000_CPG_SGD4_VIO_DP_OTHER are changed, reordered, or removed when
the hardware documentation is finalized, it could break backward
compatibility with device trees created using these preliminary bindings.

Since follow-up patches in this series use these preliminary IDs, is there a
plan to stabilize these definitions before merging to avoid long-term
maintenance hazards?

>  
>  #endif /* __DT_BINDINGS_CLOCK_RENESAS_R8A78000_CPG_H__ */

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260917-epaul-v7-3-rc1-x5h-vsp-fcp-v1-0-4c72d4e086dd@ideasonboard.com?part=1