Commit 4411a2cc authored by Geert Uytterhoeven's avatar Geert Uytterhoeven Committed by Wolfram Sang

dt-bindings: i2c: i2c-demux-pinctrl: Convert to json-schema

Convert the pinctrl-based I2C bus demultiplexer Device Tree binding
documentation to json-schema.

Update the example to match reality.
Signed-off-by: default avatarGeert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: default avatarWolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: default avatarConor Dooley <conor.dooley@microchip.com>
Signed-off-by: default avatarWolfram Sang <wsa@kernel.org>
parent 7ba2b17a
Pinctrl-based I2C Bus DeMux
This binding describes an I2C bus demultiplexer that uses pin multiplexing to
route the I2C signals, and represents the pin multiplexing configuration using
the pinctrl device tree bindings. This may be used to select one I2C IP core at
runtime which may have a better feature set for a given task than another I2C
IP core on the SoC. The most simple example is to fall back to GPIO bitbanging
if your current runtime configuration hits an errata of the internal IP core.
+-------------------------------+
| SoC |
| | +-----+ +-----+
| +------------+ | | dev | | dev |
| |I2C IP Core1|--\ | +-----+ +-----+
| +------------+ \-------+ | | |
| |Pinctrl|--|------+--------+
| +------------+ +-------+ |
| |I2C IP Core2|--/ |
| +------------+ |
| |
+-------------------------------+
Required properties:
- compatible: "i2c-demux-pinctrl"
- i2c-parent: List of phandles of I2C masters available for selection. The first
one will be used as default.
- i2c-bus-name: The name of this bus. Also needed as pinctrl-name for the I2C
parents.
Furthermore, I2C mux properties and child nodes. See i2c-mux.yaml in this
directory.
Example:
Here is a snipplet for a bus to be demuxed. It contains various i2c clients for
HDMI, so the bus is named "i2c-hdmi":
i2chdmi: i2c@8 {
compatible = "i2c-demux-pinctrl";
i2c-parent = <&gpioi2c>, <&iic2>, <&i2c2>;
i2c-bus-name = "i2c-hdmi";
#address-cells = <1>;
#size-cells = <0>;
ak4643: sound-codec@12 {
compatible = "asahi-kasei,ak4643";
#sound-dai-cells = <0>;
reg = <0x12>;
};
composite-in@20 {
compatible = "adi,adv7180";
reg = <0x20>;
remote = <&vin1>;
port {
adv7180: endpoint {
bus-width = <8>;
remote-endpoint = <&vin1ep0>;
};
};
};
hdmi@39 {
compatible = "adi,adv7511w";
reg = <0x39>;
interrupt-parent = <&gpio1>;
interrupts = <15 IRQ_TYPE_LEVEL_LOW>;
adi,input-depth = <8>;
adi,input-colorspace = "rgb";
adi,input-clock = "1x";
adi,input-style = <1>;
adi,input-justification = "evenly";
ports {
#address-cells = <1>;
#size-cells = <0>;
port@0 {
reg = <0>;
adv7511_in: endpoint {
remote-endpoint = <&du_out_lvds0>;
};
};
port@1 {
reg = <1>;
adv7511_out: endpoint {
remote-endpoint = <&hdmi_con>;
};
};
};
};
};
And for clarification, here are the snipplets for the i2c-parents:
gpioi2c: i2c@9 {
#address-cells = <1>;
#size-cells = <0>;
compatible = "i2c-gpio";
gpios = <&gpio5 6 GPIO_ACTIVE_HIGH /* sda */
&gpio5 5 GPIO_ACTIVE_HIGH /* scl */
>;
i2c-gpio,delay-us = <5>;
};
...
&i2c2 {
pinctrl-0 = <&i2c2_pins>;
pinctrl-names = "i2c-hdmi";
clock-frequency = <100000>;
};
...
&iic2 {
pinctrl-0 = <&iic2_pins>;
pinctrl-names = "i2c-hdmi";
clock-frequency = <100000>;
};
Please note:
- pinctrl properties for the parent I2C controllers need a pinctrl state
with the same name as i2c-bus-name, not "default"!
- the i2c masters must have their status "disabled". This driver will
enable them at runtime when needed.
# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
%YAML 1.2
---
$id: http://devicetree.org/schemas/i2c/i2c-demux-pinctrl.yaml#
$schema: http://devicetree.org/meta-schemas/core.yaml#
title: Pinctrl-based I2C Bus Demultiplexer
maintainers:
- Wolfram Sang <wsa+renesas@sang-engineering.com>
description: |
This binding describes an I2C bus demultiplexer that uses pin multiplexing to
route the I2C signals, and represents the pin multiplexing configuration
using the pinctrl device tree bindings. This may be used to select one I2C
IP core at runtime which may have a better feature set for a given task than
another I2C IP core on the SoC. The most simple example is to fall back to
GPIO bitbanging if your current runtime configuration hits an errata of the
internal IP core.
+-------------------------------+
| SoC |
| | +-----+ +-----+
| +------------+ | | dev | | dev |
| |I2C IP Core1|--\ | +-----+ +-----+
| +------------+ \-------+ | | |
| |Pinctrl|--|------+--------+
| +------------+ +-------+ |
| |I2C IP Core2|--/ |
| +------------+ |
| |
+-------------------------------+
allOf:
- $ref: i2c-mux.yaml
- $ref: /schemas/i2c/i2c-controller.yaml#
properties:
compatible:
const: i2c-demux-pinctrl
i2c-parent:
$ref: /schemas/types.yaml#/definitions/phandle-array
description:
List of phandles of I2C masters available for selection. The first one
will be used as default.
i2c-bus-name:
$ref: /schemas/types.yaml#/definitions/string
description:
The name of this bus. Also needed as pinctrl-name for the I2C parents.
required:
- compatible
- i2c-parent
- i2c-bus-name
unevaluatedProperties: false
examples:
- |
#include <dt-bindings/gpio/gpio.h>
#include <dt-bindings/interrupt-controller/irq.h>
gpioi2c2: i2c-9 {
#address-cells = <1>;
#size-cells = <0>;
compatible = "i2c-gpio";
scl-gpios = <&gpio5 5 (GPIO_ACTIVE_HIGH | GPIO_OPEN_DRAIN)>;
sda-gpios = <&gpio5 6 (GPIO_ACTIVE_HIGH | GPIO_OPEN_DRAIN)>;
i2c-gpio,delay-us = <5>;
// The I2C controller must have its status "disabled". The I2C bus
// demultiplexer will enable it at runtime when needed.
status = "disabled";
};
iic2: i2c@e6520000 {
reg = <0xe6520000 0x425>;
pinctrl-0 = <&iic2_pins>;
// The pinctrl property for the parent I2C controller needs a pinctrl
// state with the same name as i2c-bus-name in the I2C bus demultiplexer
// node, not "default"!
pinctrl-names = "i2c-hdmi";
clock-frequency = <100000>;
// The I2C controller must have its status "disabled". The I2C bus
// demultiplexer will enable it at runtime when needed.
status = "disabled";
};
i2c2: i2c@e6530000 {
reg = <0 0xe6530000 0 0x40>;
pinctrl-0 = <&i2c2_pins>;
// The pinctrl property for the parent I2C controller needs a pinctrl
// state with the same name as i2c-bus-name in the I2C bus demultiplexer
// node, not "default"!
pinctrl-names = "i2c-hdmi";
clock-frequency = <100000>;
// The I2C controller must have its status "disabled". The I2C bus
// demultiplexer will enable it at runtime when needed.
status = "disabled";
};
// Example for a bus to be demuxed. It contains various I2C clients for
// HDMI, so the bus is named "i2c-hdmi":
i2chdmi: i2c-mux3 {
compatible = "i2c-demux-pinctrl";
i2c-parent = <&iic2>, <&i2c2>, <&gpioi2c2>;
i2c-bus-name = "i2c-hdmi";
#address-cells = <1>;
#size-cells = <0>;
ak4643: codec@12 {
compatible = "asahi-kasei,ak4643";
#sound-dai-cells = <0>;
reg = <0x12>;
};
composite-in@20 {
compatible = "adi,adv7180";
reg = <0x20>;
port {
adv7180: endpoint {
bus-width = <8>;
remote-endpoint = <&vin1ep0>;
};
};
};
hdmi@39 {
compatible = "adi,adv7511w";
reg = <0x39>;
interrupt-parent = <&gpio1>;
interrupts = <15 IRQ_TYPE_LEVEL_LOW>;
clocks = <&cec_clock>;
clock-names = "cec";
avdd-supply = <&fixedregulator1v8>;
dvdd-supply = <&fixedregulator1v8>;
pvdd-supply = <&fixedregulator1v8>;
dvdd-3v-supply = <&fixedregulator3v3>;
bgvdd-supply = <&fixedregulator1v8>;
adi,input-depth = <8>;
adi,input-colorspace = "rgb";
adi,input-clock = "1x";
ports {
#address-cells = <1>;
#size-cells = <0>;
port@0 {
reg = <0>;
adv7511_in: endpoint {
remote-endpoint = <&lvds0_out>;
};
};
port@1 {
reg = <1>;
adv7511_out: endpoint {
remote-endpoint = <&hdmi_con_out>;
};
};
};
};
};
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