RE: [PATCH v2 09/14] dt-bindings: pinctrl: realtek: Rename 'realtek,duty-cycle' to 'realtek,pulse-width-adjust'

[Yu-Chun Lin [林祐君]]

> On 09/03/2026 10:18, Yu-Chun Lin [林祐君] wrote:
> >> On Fri, Mar 06, 2026 at 03:52:39PM +0800, Yu-Chun Lin wrote:
> >>> From: Tzuyi Chang <tychang@xxxxxxxxxxx>
> >>>
> >>> Rename 'realtek,duty-cycle' to 'realtek,pulse-width-adjust'.
> >>>
> >>> The previous name was misleading because this hardware block is not
> >>> a PWM generator. It does not generate a signal with a specific
> >>> frequency and duty ratio.
> >>>
> >>> Instead, it provides a fixed nanosecond-level adjustment to the
> >>> rising/ falling edges of an existing signal.
> >>>
> >>> Signed-off-by: Tzuyi Chang <tychang@xxxxxxxxxxx>
> >>> Co-developed-by: Yu-Chun Lin <eleanor.lin@xxxxxxxxxxx>
> >>> Signed-off-by: Yu-Chun Lin <eleanor.lin@xxxxxxxxxxx>
> >>> ---
> >>>  .../bindings/pinctrl/realtek,rtd1315e-pinctrl.yaml       | 9 ++++++---
> >>>  .../bindings/pinctrl/realtek,rtd1319d-pinctrl.yaml       | 9 ++++++---
> >>>  .../bindings/pinctrl/realtek,rtd1619b-pinctrl.yaml       | 9 ++++++---
> >>>  3 files changed, 18 insertions(+), 9 deletions(-)
> >>>
> >>> diff --git
> >>> a/Documentation/devicetree/bindings/pinctrl/realtek,rtd1315e-pinctrl
> >>> .y
> >>> aml
> >>> b/Documentation/devicetree/bindings/pinctrl/realtek,rtd1315e-pinctrl
> >>> .y aml index 90bd49d87d2e..7b3888b2cea8 100644
> >>> ---
> >>> a/Documentation/devicetree/bindings/pinctrl/realtek,rtd1315e-pinctrl
> >>> .y
> >>> aml
> >>> +++ b/Documentation/devicetree/bindings/pinctrl/realtek,rtd1315e-pin
> >>> +++ ct
> >>> +++ rl.yaml
> >>> @@ -133,10 +133,13 @@ patternProperties:
> >>>          minimum: 0
> >>>          maximum: 7
> >>>
> >>> -      realtek,duty-cycle:
> >>> +      realtek,pulse-width-adjust:
> >>
> >> No, that's ABI break without explanation. "misleading" is not the
> >> sufficient argument for breaking ABI.
> >> You are stuck with the ABI you added back in 2023.
> >>
> >> Best regards,
> >> Krzysztof
> >
> > The reason I renamed 'realtek,duty-cycle' to
> > 'realtek,pulse-width-adjust' is that during the v1 review, it was
> > pointed out that the name caused confusion with standard PWM bindings
> > [1]. Since I need to modify the driver logic to address this, I intended to
> update the binding simultaneously.
> 
> Again, confusion is not reason to break ABI.
> 
> >
> > Although the binding was added in 2023, there are currently no DTS
> > files in the mainline kernel that use the 1315e, 1319d, or 1619b pinctrl
> device nodes.
> 
> Still ABI.
> 
> > Therefore, changing this property name will not break any existing
> > device support in the mainline tree.
> 
> Yeah, but will break all other users.
> 
> Best regards,
> Krzysztof

I understand your concern. I will drop the property rename and keep
realtek,duty-cycle, but I will update its description in v3 to make it clearer.

Hi Linus,
Although you agreed with the rename to realtek,pulse-width-adjust in v1, I
will revert to the original name realtek,duty-cycle to strictly respect the
DT backward compatibility rules. I hope this is fine with you.

Best regards,
Yu-Chun