u-boot/doc/device-tree-bindings/pinctrl/nexell,s5pxx18-pinctrl.txt
Simon Glass c8ef3eed61 dm: doc: Update device tree binding docs for new schema
Now that Linux has accepted these tags, move U-Boot over to use them.

Signed-off-by: Simon Glass <sjg@chromium.org>
2023-02-14 09:43:27 -07:00

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Binding for Nexell s5pxx18 pin cotroller
========================================
Nexell's ARM bases SoC's integrates a GPIO and Pin mux/config hardware
controller. It controls the input/output settings on the available pads/pins
and also provides ability to multiplex and configure the output of various
on-chip controllers onto these pads.
Please refer to pinctrl-bindings.txt in this directory for details of the
common pinctrl bindings used by client devices, including the meaning of the
phrase "pin configuration node".
Required properties:
- compatible: "nexell,s5pxx18-pinctrl"
- reg: should be register base and length as documented in the datasheet
- interrupts: interrupt specifier for the controller over gpio and alive pins
Example:
pinctrl_0: pinctrl@c0010000 {
compatible = "nexell,s5pxx18-pinctrl";
reg = <0xc0010000 0xf000>;
bootph-all;
};
Nexell's pin configuration nodes act as a container for an arbitrary number of
subnodes. Each of these subnodes represents some desired configuration for a
pin, a group, or a list of pins or groups. This configuration can include the
mux function to select on those pin(s)/group(s), and various pin configuration
parameters.
Child nodes must be set at least one of the following settings:
- pins = Select pins for using this function.
- pin-function = Select the function for use in a selected pin.
- pin-pull = Pull up/down configuration.
- pin-strength = Drive strength configuration.
Valid values for nexell,pins are:
"gpioX-N" : X in {A,B,C,D,E}, N in {0-31}
Valid values for nexell,pin-function are:
"N" : N in {0-3}.
This setting means that the value is different for each pin.
Please refer to datasheet.
Valid values for nexell,pin-pull are:
"N" : 0 - Down, 1 - Up, 2 - Off
Valid values for nexell,pin-strength are:
"N" : 0,1,2,3
Example:
- pin settings
mmc0_clk: mmc0-clk {
pins = "gpioa-29";
pin-function = <1>;
pin-pull = <2>;
pin-strength = <2>;
};
mmc0_cmd: mmc0-cmd {
pins = "gpioa-31";
pin-function = <1>;
pin-pull = <2>;
pin-strength = <1>;
};
mmc0_bus4: mmc0-bus-width4 {
pins = "gpiob-1, gpiob-3, gpiob-5, gpiob-7";
pin-function = <1>;
pin-pull = <2>;
pin-strength = <1>;
};
- used by client devices
mmc0:mmc@... {
pinctrl-names = "default";
pinctrl-0 = <&mmc0_clk>, <&mmc0_cmd>, <&mmc0_bus4>;
...
};