Re: [PATCH V4 04/10] dt-bindings: timestamp: Add nvidia,gpio-controller

Krzysztof Kozlowski
2023-03-25T11:07:15Z

On 23/03/2023 02:29, Dipen Patel wrote:
> Introducing nvidia,gpio-controller property from Tegra234 SoCs onwards.
> This is done to help below case.
>
> Without this property code would look like:
> if (of_device_is_compatible(dev->of_node, "nvidia,tegra194-gte-aon"))
> hte_dev->c = gpiochip_find("tegra194-gpio-aon",
> tegra_get_gpiochip_from_name);
> else if (of_device_is_compatible(dev->of_node, "nvidia,tegra234-gte-aon"))
> hte_dev->c = gpiochip_find("tegra234-gpio-aon",
> tegra_get_gpiochip_from_name);
> else
> return -ENODEV;
>
> This means for every future addition of the compatible string, if else
> condition statements have to be expanded.
>
> With the property:
> gpio_ctrl = of_parse_phandle(dev->of_node, "nvidia,gpio-controller", 0);
> ....
> hte_dev->c = gpiochip_find(gpio_ctrl, tegra_get_gpiochip_from_of_node);
>
> This simplifies the code significantly. The introdunction of this
> property/binding does not break existing Tegra194 provider driver.
>
> Signed-off-by: Dipen Patel <dipenp@nvidia.com>
> ---
> .../timestamp/nvidia,tegra194-hte.yaml | 31 +++++++++++++++++--
> 1 file changed, 29 insertions(+), 2 deletions(-)
>
> diff --git a/Documentation/devicetree/bindings/timestamp/nvidia,tegra194-hte.yaml b/Documentation/devicetree/bindings/timestamp/nvidia,tegra194-hte.yaml
> index eafc33e9ae2e..841273a3d8ae 100644
> --- a/Documentation/devicetree/bindings/timestamp/nvidia,tegra194-hte.yaml
> +++ b/Documentation/devicetree/bindings/timestamp/nvidia,tegra194-hte.yaml
> @@ -51,6 +51,12 @@ properties:
> LIC instance has 11 slices and Tegra234 LIC has 17 slices.
> enum: [3, 11, 17]
>
> + nvidia,gpio-controller:
> + $ref: /schemas/types.yaml#/definitions/phandle
> + description:
> + The phandle to AON gpio controller instance. This is required to handle
> + namespace conversion between GPIO and GTE.
> +
> '#timestamp-cells':
> description:
> This represents number of line id arguments as specified by the
> @@ -65,22 +71,43 @@ required:
> - interrupts
> - "#timestamp-cells"
>
> +allOf:
> + - if:
> + properties:
> + compatible:
> + contains:
> + enum:
> + - nvidia,tegra234-gte-aon
> + then:
> + required:
> + - nvidia,gpio-controller
> +
> additionalProperties: false
>
> examples:
> - |
> tegra_hte_aon: timestamp@c1e0000 {
> compatible = "nvidia,tegra194-gte-aon";
> - reg = <0xc1e0000 0x10000>;
> + reg = <0x0 0xc1e0000 0x0 0x10000>;

This is not really explained in commit msg... are you sure you tested it?

Best regards,
Krzysztof