[PATCH 2/3 v4] dt-bindings: gpio: aspeed: Add SGPIO support

[Andrew Jeffery]

The subject is largely correct, but please see the discussion on the driver patch
about how to clean up the [PATCH ...] prefix.

On Thu, 18 Jul 2019, at 05:42, Hongwei Zhang wrote:
> Add bindings to support SGPIO on AST2400 or AST2500.
> 
> Signed-off-by: Hongwei Zhang <hongweiz at ami.com>
> ---
>  .../devicetree/bindings/gpio/sgpio-aspeed.txt      | 55 ++++++++++++++++++++++
>  1 file changed, 55 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/gpio/sgpio-aspeed.txt
> 
> diff --git a/Documentation/devicetree/bindings/gpio/sgpio-aspeed.txt 
> b/Documentation/devicetree/bindings/gpio/sgpio-aspeed.txt
> new file mode 100644
> index 0000000..2d6305e
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/gpio/sgpio-aspeed.txt
> @@ -0,0 +1,55 @@
> +Aspeed SGPIO controller Device Tree Bindings
> +-------------------------------------------
> +
> +This SGPIO controller is for ASPEED AST2500 SoC, it supports up to 80 
> full 
> +featured Serial GPIOs. Each of the Serial GPIO pins can be programmed 
> to 
> +support the following options:
> +- Support interrupt option for each input port and various interrupt 
> +  sensitivity option (level-high, level-low, edge-high, edge-low)
> +- Support reset tolerance option for each output port
> +- Directly connected to APB bus and its shift clock is from APB bus 
> clock
> +  divided by a programmable value.
> +- Co-work with external signal-chained TTL components (74LV165/74LV595)
> +
> +
> +Required properties:
> +
> +- compatible		: Either "aspeed,ast2400-sgpio" or "aspeed,ast2500-sgpio"
> +
> +- #gpio-cells 		: Should be two
> +			  - First cell is the GPIO line number
> +			  - Second cell is used to specify optional
> +			    parameters (unused)
> +
> +- reg			: Address and length of the register set for the device
> +- gpio-controller	: Marks the device node as a GPIO controller
> +- interrupts		: Interrupt specifier (see interrupt bindings for
> +			  details)
> +
> +- interrupt-controller	: Mark the GPIO controller as an 
> interrupt-controller
> +
> +- nr-gpios		: number of GPIO pins to serialise. 
> +			  (should be multiple of 8, up to 80 pins)

Please change the property name to "ngpios", as per the generic GPIO
bindings[1].

[1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/devicetree/bindings/gpio/gpio.txt?h=v5.2#n141

Cheers,

Andrew

> +
> +- clocks                : A phandle to the APB clock for SGPM clock 
> division
> +
> +- bus-frequency		: SGPM CLK frequency
> +
> +
> +The sgpio and interrupt properties are further described in their 
> respective bindings documentation:
> +
> +- Documentation/devicetree/bindings/sgpio/gpio.txt
> +- Documentation/devicetree/bindings/interrupt-controller/interrupts.txt
> +
> +  Example:
> +	sgpio: sgpio at 1e780200 {
> +		#gpio-cells = <2>;
> +		compatible = "aspeed,ast2500-sgpio";
> +		gpio-controller;
> +		interrupts = <40>;
> +		reg = <0x1e780200 0x0100>;
> +		clocks = <&syscon ASPEED_CLK_APB>;
> +		interrupt-controller;
> +		nr-gpios = <8>;
> +		bus-frequency = <12000000>;
> +	};
> -- 
> 2.7.4
> 
>