Commit a404a636 authored by Rob Herring's avatar Rob Herring

dt-bindings: i2c: Convert i2c-mux bindings to DT schema

As some of the example I2C devices don't have schemas yet, change them to
ones that do.

Cc: Peter Rosin <peda@axentia.se>
Acked-by: default avatarWolfram Sang <wsa@kernel.org>
Acked-by: default avatarPeter Rosin <peda@axentia.se>
Signed-off-by: default avatarRob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20210526184839.2937899-5-robh@kernel.org
parent 9b358af7
...@@ -27,7 +27,7 @@ Required properties: ...@@ -27,7 +27,7 @@ Required properties:
- i2c-bus-name: The name of this bus. Also needed as pinctrl-name for the I2C - i2c-bus-name: The name of this bus. Also needed as pinctrl-name for the I2C
parents. parents.
Furthermore, I2C mux properties and child nodes. See i2c-mux.txt in this Furthermore, I2C mux properties and child nodes. See i2c-mux.yaml in this
directory. directory.
Example: Example:
......
...@@ -22,8 +22,8 @@ Required properties: ...@@ -22,8 +22,8 @@ Required properties:
- i2c-parent: The phandle of the I2C bus that this multiplexer's master-side - i2c-parent: The phandle of the I2C bus that this multiplexer's master-side
port is connected to. port is connected to.
- mux-gpios: list of gpios used to control the muxer - mux-gpios: list of gpios used to control the muxer
* Standard I2C mux properties. See i2c-mux.txt in this directory. * Standard I2C mux properties. See i2c-mux.yaml in this directory.
* I2C child bus nodes. See i2c-mux.txt in this directory. * I2C child bus nodes. See i2c-mux.yaml in this directory.
Optional properties: Optional properties:
- idle-state: value to set the muxer to when idle. When no value is - idle-state: value to set the muxer to when idle. When no value is
......
General Purpose I2C Bus Mux
This binding describes an I2C bus multiplexer that uses a mux controller
from the mux subsystem to route the I2C signals.
.-----. .-----.
| dev | | dev |
.------------. '-----' '-----'
| SoC | | |
| | .--------+--------'
| .------. | .------+ child bus A, on MUX value set to 0
| | I2C |-|--| Mux |
| '------' | '--+---+ child bus B, on MUX value set to 1
| .------. | | '----------+--------+--------.
| | MUX- | | | | | |
| | Ctrl |-|-----+ .-----. .-----. .-----.
| '------' | | dev | | dev | | dev |
'------------' '-----' '-----' '-----'
Required properties:
- compatible: i2c-mux
- i2c-parent: The phandle of the I2C bus that this multiplexer's master-side
port is connected to.
- mux-controls: The phandle of the mux controller to use for operating the
mux.
* Standard I2C mux properties. See i2c-mux.txt in this directory.
* I2C child bus nodes. See i2c-mux.txt in this directory. The sub-bus number
is also the mux-controller state described in ../mux/mux-controller.yaml
Optional properties:
- mux-locked: If present, explicitly allow unrelated I2C transactions on the
parent I2C adapter at these times:
+ during setup of the multiplexer
+ between setup of the multiplexer and the child bus I2C transaction
+ between the child bus I2C transaction and releasing of the multiplexer
+ during releasing of the multiplexer
However, I2C transactions to devices behind all I2C multiplexers connected
to the same parent adapter that this multiplexer is connected to are blocked
for the full duration of the complete multiplexed I2C transaction (i.e.
including the times covered by the above list).
If mux-locked is not present, the multiplexer is assumed to be parent-locked.
This means that no unrelated I2C transactions are allowed on the parent I2C
adapter for the complete multiplexed I2C transaction.
The properties of mux-locked and parent-locked multiplexers are discussed
in more detail in Documentation/i2c/i2c-topology.rst.
For each i2c child node, an I2C child bus will be created. They will
be numbered based on their order in the device tree.
Whenever an access is made to a device on a child bus, the value set
in the relevant node's reg property will be set as the state in the
mux controller.
Example:
mux: mux-controller {
compatible = "gpio-mux";
#mux-control-cells = <0>;
mux-gpios = <&pioA 0 GPIO_ACTIVE_HIGH>,
<&pioA 1 GPIO_ACTIVE_HIGH>;
};
i2c-mux {
compatible = "i2c-mux";
mux-locked;
i2c-parent = <&i2c1>;
mux-controls = <&mux>;
#address-cells = <1>;
#size-cells = <0>;
i2c@1 {
reg = <1>;
#address-cells = <1>;
#size-cells = <0>;
ssd1307: oled@3c {
compatible = "solomon,ssd1307fb-i2c";
reg = <0x3c>;
pwms = <&pwm 4 3000>;
reset-gpios = <&gpio2 7 1>;
reset-active-low;
};
};
i2c@3 {
reg = <3>;
#address-cells = <1>;
#size-cells = <0>;
pca9555: pca9555@20 {
compatible = "nxp,pca9555";
gpio-controller;
#gpio-cells = <2>;
reg = <0x20>;
};
};
};
# SPDX-License-Identifier: GPL-2.0
%YAML 1.2
---
$id: http://devicetree.org/schemas/i2c/i2c-mux-gpmux.yaml#
$schema: http://devicetree.org/meta-schemas/core.yaml#
title: General Purpose I2C Bus Mux
maintainers:
- Peter Rosin <peda@axentia.se>
description: |+
This binding describes an I2C bus multiplexer that uses a mux controller
from the mux subsystem to route the I2C signals.
.-----. .-----.
| dev | | dev |
.------------. '-----' '-----'
| SoC | | |
| | .--------+--------'
| .------. | .------+ child bus A, on MUX value set to 0
| | I2C |-|--| Mux |
| '------' | '--+---+ child bus B, on MUX value set to 1
| .------. | | '----------+--------+--------.
| | MUX- | | | | | |
| | Ctrl |-|-----+ .-----. .-----. .-----.
| '------' | | dev | | dev | | dev |
'------------' '-----' '-----' '-----'
allOf:
- $ref: /schemas/i2c/i2c-mux.yaml#
properties:
compatible:
const: i2c-mux
i2c-parent:
$ref: /schemas/types.yaml#/definitions/phandle
description:
The phandle of the I2C bus that this multiplexer's master-side port is
connected to.
mux-controls:
maxItems: 1
description:
The mux-controller states are the I2C sub-bus numbers.
mux-locked:
type: boolean
description: |
Explicitly allow unrelated I2C transactions on the parent I2C adapter at
these times:
- during setup of the multiplexer
- between setup of the multiplexer and the child bus I2C transaction
- between the child bus I2C transaction and releasing of the multiplexer
- during releasing of the multiplexer
However, I2C transactions to devices behind all I2C multiplexers connected
to the same parent adapter that this multiplexer is connected to are blocked
for the full duration of the complete multiplexed I2C transaction (i.e.
including the times covered by the above list).
If mux-locked is not present, the multiplexer is assumed to be parent-locked.
This means that no unrelated I2C transactions are allowed on the parent I2C
adapter for the complete multiplexed I2C transaction.
The properties of mux-locked and parent-locked multiplexers are discussed
in more detail in Documentation/i2c/i2c-topology.rst.
required:
- compatible
- i2c-parent
- mux-controls
unevaluatedProperties: false
examples:
- |
#include <dt-bindings/gpio/gpio.h>
mux: mux-controller {
compatible = "gpio-mux";
#mux-control-cells = <0>;
mux-gpios = <&pioA 0 GPIO_ACTIVE_HIGH>,
<&pioA 1 GPIO_ACTIVE_HIGH>;
};
i2c-mux {
compatible = "i2c-mux";
mux-locked;
i2c-parent = <&i2c1>;
mux-controls = <&mux>;
#address-cells = <1>;
#size-cells = <0>;
i2c@1 {
reg = <1>;
#address-cells = <1>;
#size-cells = <0>;
gpio@20 {
compatible = "nxp,pca9555";
gpio-controller;
#gpio-cells = <2>;
reg = <0x20>;
};
};
i2c@3 {
reg = <3>;
#address-cells = <1>;
#size-cells = <0>;
gpio@20 {
compatible = "nxp,pca9555";
gpio-controller;
#gpio-cells = <2>;
reg = <0x20>;
};
};
};
...
...@@ -8,8 +8,8 @@ Required Properties: ...@@ -8,8 +8,8 @@ Required Properties:
The following required properties are defined externally: The following required properties are defined externally:
- Standard I2C mux properties. See i2c-mux.txt in this directory. - Standard I2C mux properties. See i2c-mux.yaml in this directory.
- I2C child bus nodes. See i2c-mux.txt in this directory. - I2C child bus nodes. See i2c-mux.yaml in this directory.
Optional Properties: Optional Properties:
......
...@@ -28,9 +28,9 @@ Also required are: ...@@ -28,9 +28,9 @@ Also required are:
* Standard pinctrl properties that specify the pin mux state for each child * Standard pinctrl properties that specify the pin mux state for each child
bus. See ../pinctrl/pinctrl-bindings.txt. bus. See ../pinctrl/pinctrl-bindings.txt.
* Standard I2C mux properties. See i2c-mux.txt in this directory. * Standard I2C mux properties. See i2c-mux.yaml in this directory.
* I2C child bus nodes. See i2c-mux.txt in this directory. * I2C child bus nodes. See i2c-mux.yaml in this directory.
For each named state defined in the pinctrl-names property, an I2C child bus For each named state defined in the pinctrl-names property, an I2C child bus
will be created. I2C child bus numbers are assigned based on the index into will be created. I2C child bus numbers are assigned based on the index into
......
...@@ -7,8 +7,8 @@ Required properties: ...@@ -7,8 +7,8 @@ Required properties:
- compatible: i2c-mux-reg - compatible: i2c-mux-reg
- i2c-parent: The phandle of the I2C bus that this multiplexer's master-side - i2c-parent: The phandle of the I2C bus that this multiplexer's master-side
port is connected to. port is connected to.
* Standard I2C mux properties. See i2c-mux.txt in this directory. * Standard I2C mux properties. See i2c-mux.yaml in this directory.
* I2C child bus nodes. See i2c-mux.txt in this directory. * I2C child bus nodes. See i2c-mux.yaml in this directory.
Optional properties: Optional properties:
- reg: this pair of <offset size> specifies the register to control the mux. - reg: this pair of <offset size> specifies the register to control the mux.
......
Common i2c bus multiplexer/switch properties.
An i2c bus multiplexer/switch will have several child busses that are
numbered uniquely in a device dependent manner. The nodes for an i2c bus
multiplexer/switch will have one child node for each child bus.
Optional properties:
- #address-cells = <1>;
This property is required if the i2c-mux child node does not exist.
- #size-cells = <0>;
This property is required if the i2c-mux child node does not exist.
- i2c-mux
For i2c multiplexers/switches that have child nodes that are a mixture
of both i2c child busses and other child nodes, the 'i2c-mux' subnode
can be used for populating the i2c child busses. If an 'i2c-mux'
subnode is present, only subnodes of this will be considered as i2c
child busses.
Required properties for the i2c-mux child node:
- #address-cells = <1>;
- #size-cells = <0>;
Required properties for i2c child bus nodes:
- #address-cells = <1>;
- #size-cells = <0>;
- reg : The sub-bus number.
Optional properties for i2c child bus nodes:
- Other properties specific to the multiplexer/switch hardware.
- Child nodes conforming to i2c bus binding
Example :
/*
An NXP pca9548 8 channel I2C multiplexer at address 0x70
with two NXP pca8574 GPIO expanders attached, one each to
ports 3 and 4.
*/
mux@70 {
compatible = "nxp,pca9548";
reg = <0x70>;
#address-cells = <1>;
#size-cells = <0>;
i2c@3 {
#address-cells = <1>;
#size-cells = <0>;
reg = <3>;
gpio1: gpio@38 {
compatible = "nxp,pca8574";
reg = <0x38>;
#gpio-cells = <2>;
gpio-controller;
};
};
i2c@4 {
#address-cells = <1>;
#size-cells = <0>;
reg = <4>;
gpio2: gpio@38 {
compatible = "nxp,pca8574";
reg = <0x38>;
#gpio-cells = <2>;
gpio-controller;
};
};
};
# SPDX-License-Identifier: GPL-2.0
%YAML 1.2
---
$id: http://devicetree.org/schemas/i2c/i2c-mux.yaml#
$schema: http://devicetree.org/meta-schemas/core.yaml#
title: Common i2c bus multiplexer/switch properties.
maintainers:
- Peter Rosin <peda@axentia.se>
description: |+
An i2c bus multiplexer/switch will have several child busses that are numbered
uniquely in a device dependent manner. The nodes for an i2c bus
multiplexer/switch will have one child node for each child bus.
For i2c multiplexers/switches that have child nodes that are a mixture of both
i2c child busses and other child nodes, the 'i2c-mux' subnode can be used for
populating the i2c child busses. If an 'i2c-mux' subnode is present, only
subnodes of this will be considered as i2c child busses.
properties:
$nodename:
pattern: '^(i2c-?)?mux'
'#address-cells':
const: 1
'#size-cells':
const: 0
patternProperties:
'^i2c@[0-9a-f]+$':
$ref: /schemas/i2c/i2c-controller.yaml
unevaluatedProperties: false
properties:
reg:
description: The mux selector sub-bus number for the child I2C bus.
maxItems: 1
additionalProperties: true
examples:
- |
/*
* An NXP pca9548 8 channel I2C multiplexer at address 0x70
* with two NXP pca8574 GPIO expanders attached, one each to
* ports 3 and 4.
*/
i2c {
#address-cells = <1>;
#size-cells = <0>;
i2c-mux@70 {
compatible = "nxp,pca9548";
reg = <0x70>;
#address-cells = <1>;
#size-cells = <0>;
i2c@3 {
#address-cells = <1>;
#size-cells = <0>;
reg = <3>;
gpio@20 {
compatible = "nxp,pca9555";
gpio-controller;
#gpio-cells = <2>;
reg = <0x20>;
};
};
i2c@4 {
#address-cells = <1>;
#size-cells = <0>;
reg = <4>;
gpio@20 {
compatible = "nxp,pca9555";
gpio-controller;
#gpio-cells = <2>;
reg = <0x20>;
};
};
};
};
...
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