[PATCH v2] dt-bindings: gpio: pca95xx: add onnn,pca9655 compatible

[PATCH v2] dt-bindings: gpio: pca95xx: add onnn,pca9655 compatible

[Rosen Penev]

The pca9655 is the On Semi variant of the pca9555 16-bit I2C GPIO
expander. "onnn,pca9655" is already used standalone by in-tree DTS
(armada-388-clearfog, armada-388-helios4) and has a dedicated entry in
the pca953x driver's OF match table, but was never documented, causing
dtbs_check failures.

Document it alongside the other standalone entries such as
onnn,pca9654, without an nxp,pca9555 fallback, so that the existing
DTS remain valid.

Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202610021617.AlVUa9No-lkp@intel.com/
Assisted-by: LLM
Signed-off-by: Rosen Penev <rosenp@gmail.com>
---
 v2: rewrite description. Use tags from kernel test bot.
 Documentation/devicetree/bindings/gpio/gpio-pca95xx.yaml | 1 +
 1 file changed, 1 insertion(+)

diff --git a/Documentation/devicetree/bindings/gpio/gpio-pca95xx.yaml b/Documentation/devicetree/bindings/gpio/gpio-pca95xx.yaml
index 4631388a7d91..563f61e6e543 100644
--- a/Documentation/devicetree/bindings/gpio/gpio-pca95xx.yaml
+++ b/Documentation/devicetree/bindings/gpio/gpio-pca95xx.yaml
@@ -67,6 +67,7 @@ properties:
               - nxp,pcal9555a
               - onnn,cat9554
               - onnn,pca9654
+              - onnn,pca9655
               - ti,pca6107
               - ti,pca9536
               - ti,tca6408
-- 
2.56.0

Re: [PATCH v2] dt-bindings: gpio: pca95xx: add onnn,pca9655 compatible

[sashiko-bot]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Medium] dt-bindings: commit message falsely claims in-tree DTS usage
--

commit 7b4c1f570780f70afdcc949de9998c051c2323e5
Author: Rosen Penev <rosenp@gmail.com>

dt-bindings: gpio: pca95xx: add onnn,pca9655 compatible

This commit documents the onnn,pca9655 compatible string for the On Semi 
variant of the pca9555 16-bit I2C GPIO expander. It adds the string alongside 
other standalone entries without a fallback.

Closes: https://lore.kernel.org/oe-kbuild-all/202610021617.AlVUa9No-lkp@intel.com/

> The pca9655 is the On Semi variant of the pca9555 16-bit I2C GPIO
> expander. "onnn,pca9655" is already used standalone by in-tree DTS
> (armada-388-clearfog, armada-388-helios4) and has a dedicated entry in
> the pca953x driver's OF match table, but was never documented, causing
> dtbs_check failures.

[Severity: Medium]
Is this claim about in-tree DTS usage accurate? 

Looking at the armada-388-clearfog.dtsi file, the compatible string appears
to be only used within a comment:

        /*
         * This is how it should be:
         * compatible = "onnn,pca9655", "nxp,pca9555";
         * but you can't do this because of the way I2C works.
         */
        compatible = "nxp,pca9555";

Because the string is only present in a comment and the active property is
nxp,pca9555, it would not trigger dtbs_check failures. Could the commit
message be updated to reflect why the binding actually needs to be added?

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20261004191042.143713-1-rosenp@gmail.com?part=1

Re: [PATCH v2] dt-bindings: gpio: pca95xx: add onnn,pca9655 compatible

[Rosen Penev]

On Sun, Oct 4, 2026 at 12:17 PM <sashiko-bot@kernel.org> wrote:
>
> Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
> - [Medium] dt-bindings: commit message falsely claims in-tree DTS usage
> --
>
> commit 7b4c1f570780f70afdcc949de9998c051c2323e5
> Author: Rosen Penev <rosenp@gmail.com>
>
> dt-bindings: gpio: pca95xx: add onnn,pca9655 compatible
>
> This commit documents the onnn,pca9655 compatible string for the On Semi
> variant of the pca9555 16-bit I2C GPIO expander. It adds the string alongside
> other standalone entries without a fallback.
>
> Closes: https://lore.kernel.org/oe-kbuild-all/202610021617.AlVUa9No-lkp@intel.com/
>
> > The pca9655 is the On Semi variant of the pca9555 16-bit I2C GPIO
> > expander. "onnn,pca9655" is already used standalone by in-tree DTS
> > (armada-388-clearfog, armada-388-helios4) and has a dedicated entry in
> > the pca953x driver's OF match table, but was never documented, causing
> > dtbs_check failures.
>
> [Severity: Medium]
> Is this claim about in-tree DTS usage accurate?
>
> Looking at the armada-388-clearfog.dtsi file, the compatible string appears
> to be only used within a comment:
>
>         /*
>          * This is how it should be:
>          * compatible = "onnn,pca9655", "nxp,pca9555";
>          * but you can't do this because of the way I2C works.
>          */
>         compatible = "nxp,pca9555";
>
> Because the string is only present in a comment and the active property is
> nxp,pca9555, it would not trigger dtbs_check failures. Could the commit
> message be updated to reflect why the binding actually needs to be added?
This is outdated. 6dfda79476538a9aad1d2dac45453e62c6939522 in
linux-next fixes this.
>
> --
> Sashiko AI review · https://sashiko.dev/#/patchset/20261004191042.143713-1-rosenp@gmail.com?part=1

Re: [PATCH v2] dt-bindings: gpio: pca95xx: add onnn,pca9655 compatible

[Krzysztof Kozlowski]

On Sun, Oct 04, 2026 at 12:10:42PM -0700, Rosen Penev wrote:
> The pca9655 is the On Semi variant of the pca9555 16-bit I2C GPIO
> expander. "onnn,pca9655" is already used standalone by in-tree DTS

"Already" is a stretch - YOU added it here:
https://lore.kernel.org/all/20260905000415.153682-1-rosenp@gmail.com/

and that patch explained nothing about missing compatible documentation.
That patch should clearly document missing binding, so the SoC
maintainer would not pick it up.

> (armada-388-clearfog, armada-388-helios4) and has a dedicated entry in
> the pca953x driver's OF match table, but was never documented, causing
> dtbs_check failures.
> 
> Document it alongside the other standalone entries such as
> onnn,pca9654, without an nxp,pca9555 fallback, so that the existing
> DTS remain valid.

There is no existing DTs, git grep. Next is not existing, because I can
reject that DTS pull.

And what about clear comment in mainline:

 * This is how it should be:
 * compatible = "onnn,pca9655", "nxp,pca9555";
 * but you can't do this because of the way I2C works.

 Best regards,
 Krzysztof

Re: [PATCH v2] dt-bindings: gpio: pca95xx: add onnn,pca9655 compatible

[Igor Velkov]

I sent the fallback form with Helios64 as its first user:
https://lore.kernel.org/r/20261009-helios64-pca9655-v1-0-673ee4432650@iav.lv

Igor