Re: [PATCH v5 5/6] dt-bindings: pinctrl: mt8183: add binding document

From: Rob Herring
Date: Fri Dec 28 2018 - 17:04:10 EST


On Fri, Dec 28, 2018 at 04:09:40PM +0800, Erin Lo wrote:
> From: Zhiyong Tao <zhiyong.tao@xxxxxxxxxxxx>
>
> The commit adds mt8183 compatible node in binding document.
>
> Signed-off-by: Zhiyong Tao <zhiyong.tao@xxxxxxxxxxxx>
> Signed-off-by: Erin Lo <erin.lo@xxxxxxxxxxxx>
> ---
> .../devicetree/bindings/pinctrl/pinctrl-mt8183.txt | 110 +++++++++++++++++++++
> 1 file changed, 110 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/pinctrl/pinctrl-mt8183.txt
>
> diff --git a/Documentation/devicetree/bindings/pinctrl/pinctrl-mt8183.txt b/Documentation/devicetree/bindings/pinctrl/pinctrl-mt8183.txt
> new file mode 100644
> index 0000000..7b5285e
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/pinctrl/pinctrl-mt8183.txt
> @@ -0,0 +1,110 @@
> +* Mediatek MT8183 Pin Controller
> +
> +The Mediatek's Pin controller is used to control SoC pins.
> +
> +Required properties:
> +- compatible: value should be one of the following.
> + "mediatek,mt8183-pinctrl", compatible with mt8183 pinctrl.
> +- gpio-controller : Marks the device node as a gpio controller.
> +- #gpio-cells: number of cells in GPIO specifier. Since the generic GPIO
> + binding is used, the amount of cells must be specified as 2. See the below
> + mentioned gpio binding representation for description of particular cells.
> +- gpio-ranges : gpio valid number range.
> +
> + Eg: <&pio 6 0>
> + <[phandle of the gpio controller node]
> + [line number within the gpio controller]
> + [flags]>
> +
> + Values for gpio specifier:
> + - Line number: is a value between 0 to 202.
> + - Flags: bit field of flags, as defined in <dt-bindings/gpio/gpio.h>.
> + Only the following flags are supported:
> + 0 - GPIO_ACTIVE_HIGH
> + 1 - GPIO_ACTIVE_LOW
> +
> +Optional properties:
> +- reg: physicall address base for gpio base registers.

s/physicall/physical/

reg should never be optional.

Need to say how many reg entries.

> +- reg-names: gpio base registers name.

Need to say what are the names. However, I don't find the names in the
example all that useful, so I'd just drop it.

> +- interrupt-controller: Marks the device node as an interrupt controller
> +- #interrupt-cells: Should be two.
> +- interrupts : The interrupt outputs from the controller.
> +
> +Please refer to pinctrl-bindings.txt in this directory for details of the
> +common pinctrl bindings used by client devices.
> +
> +Subnode format
> +A pinctrl node should contain at least one subnodes representing the
> +pinctrl groups available on the machine. Each subnode will list the
> +pins it needs, and how they should be configured, with regard to muxer
> +configuration, pullups, drive strength, input enable/disable and input schmitt.
> +
> + node {
> + pinmux = <PIN_NUMBER_PINMUX>;
> + GENERIC_PINCONFIG;
> + };
> +
> +Required properties:
> +- pinmux: integer array, represents gpio pin number and mux setting.
> + Supported pin number and mux varies for different SoCs, and are defined
> + as macros in boot/dts/<soc>-pinfunc.h directly.
> +
> +Optional properties:
> +- GENERIC_PINCONFIG: is the generic pinconfig options to use, bias-disable,
> + bias-pull-down, bias-pull-up, input-enable, input-disable, output-low, output-high,
> + input-schmitt-enable, input-schmitt-disable and drive-strength are valid.
> +
> + Some special pins have extra pull up strength, there are R0 and R1 pull-up
> + resistors available, but for user, it's only need to set R1R0 as 00, 01, 10 or 11.
> + So when config mediatek,pull-up-adv or mediatek,pull-down-adv,
> + it support arguments for those special pins.
> +
> + When config drive-strength, it can support some arguments, such as
> + MTK_DRIVE_4mA, MTK_DRIVE_6mA, etc. See dt-bindings/pinctrl/mt65xx.h.
> +
> +Examples:
> +
> +#include "mt8183-pinfunc.h"
> +
> +...
> +{
> + pio: pinctrl@10005000 {
> + compatible = "mediatek,mt8183-pinctrl";
> + reg = <0 0x10005000 0 0x1000>,
> + <0 0x11F20000 0 0x1000>,
> + <0 0x11E80000 0 0x1000>,
> + <0 0x11E70000 0 0x1000>,
> + <0 0x11E90000 0 0x1000>,
> + <0 0x11D30000 0 0x1000>,
> + <0 0x11D20000 0 0x1000>,
> + <0 0x11C50000 0 0x1000>,
> + <0 0x11F30000 0 0x1000>;
> + reg-names = "iocfg0", "iocfg1", "iocfg2",
> + "iocfg3", "iocfg4", "iocfg5",
> + "iocfg6", "iocfg7", "iocfg8";
> + gpio-controller;
> + #gpio-cells = <2>;
> + gpio-ranges = <&pio 0 0 192>;
> + interrupt-controller;
> + interrupts = <GIC_SPI 153 IRQ_TYPE_LEVEL_HIGH>;
> + interrupt-parent = <&gic>;
> + #interrupt-cells = <2>;
> +
> + i2c0_pins_a: i2c0@0 {

unit-address without reg property is not valid.

> + pins1 {
> + pinmux = <PINMUX_GPIO48__FUNC_SCL5>,
> + <PINMUX_GPIO49__FUNC_SDA5>;
> + mediatek,pull-up-adv = <11>;
> + };
> + };
> +
> + i2c1_pins_a: i2c1@0 {
> + pins {
> + pinmux = <PINMUX_GPIO50__FUNC_SCL3>,
> + <PINMUX_GPIO51__FUNC_SDA3>;
> + mediatek,pull-down-adv = <10>;
> + };
> + };
> + ...
> + };
> +};
> --
> 1.9.1
>