Re: [PATCH v5 1/4] dt-bindings: media: ti,ds90ub953: Add new range for remote GPIO data

[Tomi Valkeinen]

Jo,

On 28/02/2026 08:18, Guoniu Zhou wrote:
> From: Guoniu Zhou <guoniu.zhou@xxxxxxx>
> 
> The DS90UB953 supports four pins, GPIO0 through GPIO3. When enabled as an
> output, it can be programed to output local data or remote data coming
> from the remote compatible deserializer.
> 
> Make a different GPIO range for remote ones.
> 
> Signed-off-by: Guoniu Zhou <guoniu.zhou@xxxxxxx>
> ---
> Changes in v5:
> - Improve the description for "#gpio-cells" as commented by Conor.
> 
> Changes in v4:
> - Use folder block instead of literal block for #gpio-cell property description.
> 
> Changes in v3:
> - Make GPIO range from 0-3 to 0-7 to support GPIO data from remote
>   compatible deserializer suggested by Rob instead of adding third
>   cell for GPIO controller.
> 
> Changes in v2:
> - Remove new property ti,gpio-data
> - Add third cell for GPIO controller to select GPIO output source.
> ---
>  Documentation/devicetree/bindings/media/i2c/ti,ds90ub953.yaml | 8 ++++++--
>  1 file changed, 6 insertions(+), 2 deletions(-)
> 
> diff --git a/Documentation/devicetree/bindings/media/i2c/ti,ds90ub953.yaml b/Documentation/devicetree/bindings/media/i2c/ti,ds90ub953.yaml
> index 2e129bf573b79e0ca8f25b4ec5fc6ea76c50abd7..143d546ecb482d2eb78a113b1a57afcbff9cca01 100644
> --- a/Documentation/devicetree/bindings/media/i2c/ti,ds90ub953.yaml
> +++ b/Documentation/devicetree/bindings/media/i2c/ti,ds90ub953.yaml
> @@ -20,9 +20,13 @@ properties:
>  
>    '#gpio-cells':
>      const: 2
> -    description:
> +    description: >
>        First cell is the GPIO pin number, second cell is the flags. The GPIO pin
> -      number must be in range of [0, 3].
> +      number must be in range of [0, 3] when enabled as an input.
> +
> +      If enabled as an output, the GPIO pin number must be in range of [0, 7].
> +      [0, 3] are for local GPIO data and [4, 7] for GPIO data coming from
> +      remote compatible deserializer.
I see there has been some discussions about this in the earlier
versions. I guess this works, but feels a bit hacky, makes the driver a
bit odd, and assumes that no consumer ever uses the same gpio from the
0-3 range and 4-7 range.

Did you try the approach where a new flag would be used to indicate the
remote gpio functionality? Any problems there? I'm not sure what's the
policy for adding custom gpio flags, though.

 Tomi