On Thu, Sep 17, 2020 at 10:53 AM Krzysztof Kozlowski <krzk@xxxxxxxxxx> wrote:
>
> Convert parts of gpio.txt bindings into common dtschema file for GPIO
> controllers. The schema enforces proper naming of GPIO controller nodes
> and GPIO hogs.
Did you not see my previous reply about a common schema? We already
have a common GPIO and hog schema in dtschema. Please add to it
whatever is missing.
My goal is all common schema end up in dtschema, but I haven't pushed
folks to do that yet. Ones I've done are there though. One issue is
what's in dtschema should be GPL/BSD and the existing text bindings
are default GPL, so there's a relicensing exercise. In some cases, the
schema is there but I haven't copied over the descriptions.
Rob
> + description:
> + Indicates the start and size of the GPIOs that can't be used.
> +
> + ngpios:
> + description: |
> + Optionally, a GPIO controller may have a "ngpios" property. This property
> + indicates the number of in-use slots of available slots for GPIOs. The
> + typical example is something like this: the hardware register is 32 bits
> + wide, but only 18 of the bits have a physical counterpart. The driver is
> + generally written so that all 32 bits can be used, but the IP block is
> + reused in a lot of designs, some using all 32 bits, some using 18 and
> + some using 12. In this case, setting "ngpios = <18>;" informs the driver
> + that only the first 18 GPIOs, at local offset 0 .. 17, are in use.
> +
> + If these GPIOs do not happen to be the first N GPIOs at offset 0...N-1,
> + an additional set of tuples is needed to specify which GPIOs are
> + unusable, with the gpio-reserved-ranges binding.
> +
> +patternProperties:
> + "^(hog-[0-9]+|.+-hog(-[0-9]+)?)$":
> + type: object
> + description:
> + The GPIO chip may contain GPIO hog definitions. GPIO hogging is a mechanism
> + providing automatic GPIO request and configuration as part of the
> + gpio-controller's driver probe function.
> + Each GPIO hog definition is represented as a child node of the GPIO controller.
> +
> + properties:
> + gpio-hog: true
> + gpios: true
> + input: true
> + output-high: true
> + output-low: true
> + line-name:
> + description:
> + The GPIO label name. If not present the node name is used.
> +
> + required:
> + - gpio-hog
> + - gpios
> +
> + oneOf:
> + - required:
> + - input
> + - required:
> + - output-high
> + - required:
> + - output-low
> +
> + additionalProperties: false
> +
> +required:
> + - "#gpio-cells"
> + - gpio-controller
> +
> +examples:
> + - |
> + gpio-controller@15000000 {
> + compatible = "foo";
> + reg = <0x15000000 0x1000>;
> + gpio-controller;
> + #gpio-cells = <2>;
> + ngpios = <18>;
> + gpio-reserved-ranges = <0 4>, <12 2>;
> + gpio-line-names = "MMC-CD", "MMC-WP", "VDD eth", "RST eth", "LED R",
> + "LED G", "LED B", "Col A", "Col B", "Col C", "Col D",
> + "Row A", "Row B", "Row C", "Row D", "NMI button",
> + "poweroff", "reset";
> + };
> +
> + - |
> + gpio-controller@1400 {
> + compatible = "fsl,qe-pario-bank-a", "fsl,qe-pario-bank";
> + reg = <0x1400 0x18>;
> + gpio-controller;
> + #gpio-cells = <2>;
> +
> + line-b-hog {
> + gpio-hog;
> + gpios = <6 0>;
> + input;
> + line-name = "foo-bar-gpio";
> + };
> + };
> --
> 2.17.1
>
