As some of the example I2C devices don't have schemas yet, change them to
ones that do.
Cc: Peter Rosin <[email protected]>
Signed-off-by: Rob Herring <[email protected]>
---
.../bindings/i2c/i2c-demux-pinctrl.txt | 2 +-
.../devicetree/bindings/i2c/i2c-mux-gpio.txt | 4 +-
.../devicetree/bindings/i2c/i2c-mux-gpmux.txt | 99 --------------
.../bindings/i2c/i2c-mux-gpmux.yaml | 124 ++++++++++++++++++
.../bindings/i2c/i2c-mux-ltc4306.txt | 4 +-
.../bindings/i2c/i2c-mux-pinctrl.txt | 4 +-
.../devicetree/bindings/i2c/i2c-mux-reg.txt | 4 +-
.../devicetree/bindings/i2c/i2c-mux.txt | 73 -----------
.../devicetree/bindings/i2c/i2c-mux.yaml | 87 ++++++++++++
9 files changed, 220 insertions(+), 181 deletions(-)
delete mode 100644 Documentation/devicetree/bindings/i2c/i2c-mux-gpmux.txt
create mode 100644 Documentation/devicetree/bindings/i2c/i2c-mux-gpmux.yaml
delete mode 100644 Documentation/devicetree/bindings/i2c/i2c-mux.txt
create mode 100644 Documentation/devicetree/bindings/i2c/i2c-mux.yaml
diff --git a/Documentation/devicetree/bindings/i2c/i2c-demux-pinctrl.txt b/Documentation/devicetree/bindings/i2c/i2c-demux-pinctrl.txt
index 81b5d55086fa..86b2e433a969 100644
--- a/Documentation/devicetree/bindings/i2c/i2c-demux-pinctrl.txt
+++ b/Documentation/devicetree/bindings/i2c/i2c-demux-pinctrl.txt
@@ -27,7 +27,7 @@ Required properties:
- 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.txt in this
+Furthermore, I2C mux properties and child nodes. See i2c-mux.yaml in this
directory.
Example:
diff --git a/Documentation/devicetree/bindings/i2c/i2c-mux-gpio.txt b/Documentation/devicetree/bindings/i2c/i2c-mux-gpio.txt
index 21da3ecbb370..e00d2b9e957a 100644
--- a/Documentation/devicetree/bindings/i2c/i2c-mux-gpio.txt
+++ b/Documentation/devicetree/bindings/i2c/i2c-mux-gpio.txt
@@ -22,8 +22,8 @@ Required properties:
- i2c-parent: The phandle of the I2C bus that this multiplexer's master-side
port is connected to.
- mux-gpios: list of gpios used to control the muxer
-* Standard I2C mux properties. See i2c-mux.txt in this directory.
-* I2C child bus nodes. 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.yaml in this directory.
Optional properties:
- idle-state: value to set the muxer to when idle. When no value is
diff --git a/Documentation/devicetree/bindings/i2c/i2c-mux-gpmux.txt b/Documentation/devicetree/bindings/i2c/i2c-mux-gpmux.txt
deleted file mode 100644
index 057083a8ba17..000000000000
--- a/Documentation/devicetree/bindings/i2c/i2c-mux-gpmux.txt
+++ /dev/null
@@ -1,99 +0,0 @@
-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>;
- };
- };
- };
diff --git a/Documentation/devicetree/bindings/i2c/i2c-mux-gpmux.yaml b/Documentation/devicetree/bindings/i2c/i2c-mux-gpmux.yaml
new file mode 100644
index 000000000000..3e6ea59aea68
--- /dev/null
+++ b/Documentation/devicetree/bindings/i2c/i2c-mux-gpmux.yaml
@@ -0,0 +1,124 @@
+# 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 <[email protected]>
+
+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>;
+ };
+ };
+ };
+...
diff --git a/Documentation/devicetree/bindings/i2c/i2c-mux-ltc4306.txt b/Documentation/devicetree/bindings/i2c/i2c-mux-ltc4306.txt
index 8b1e49cdce3f..29c4550c9782 100644
--- a/Documentation/devicetree/bindings/i2c/i2c-mux-ltc4306.txt
+++ b/Documentation/devicetree/bindings/i2c/i2c-mux-ltc4306.txt
@@ -8,8 +8,8 @@ Required Properties:
The following required properties are defined externally:
- - Standard I2C mux properties. See i2c-mux.txt in this directory.
- - I2C child bus nodes. 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.yaml in this directory.
Optional Properties:
diff --git a/Documentation/devicetree/bindings/i2c/i2c-mux-pinctrl.txt b/Documentation/devicetree/bindings/i2c/i2c-mux-pinctrl.txt
index 33119a98e144..997a287ed3f6 100644
--- a/Documentation/devicetree/bindings/i2c/i2c-mux-pinctrl.txt
+++ b/Documentation/devicetree/bindings/i2c/i2c-mux-pinctrl.txt
@@ -28,9 +28,9 @@ Also required are:
* Standard pinctrl properties that specify the pin mux state for each child
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
will be created. I2C child bus numbers are assigned based on the index into
diff --git a/Documentation/devicetree/bindings/i2c/i2c-mux-reg.txt b/Documentation/devicetree/bindings/i2c/i2c-mux-reg.txt
index de00d7fc450b..b9d9755e4172 100644
--- a/Documentation/devicetree/bindings/i2c/i2c-mux-reg.txt
+++ b/Documentation/devicetree/bindings/i2c/i2c-mux-reg.txt
@@ -7,8 +7,8 @@ Required properties:
- compatible: i2c-mux-reg
- i2c-parent: The phandle of the I2C bus that this multiplexer's master-side
port is connected to.
-* Standard I2C mux properties. See i2c-mux.txt in this directory.
-* I2C child bus nodes. 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.yaml in this directory.
Optional properties:
- reg: this pair of <offset size> specifies the register to control the mux.
diff --git a/Documentation/devicetree/bindings/i2c/i2c-mux.txt b/Documentation/devicetree/bindings/i2c/i2c-mux.txt
deleted file mode 100644
index b38f58a1c878..000000000000
--- a/Documentation/devicetree/bindings/i2c/i2c-mux.txt
+++ /dev/null
@@ -1,73 +0,0 @@
-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;
- };
- };
- };
diff --git a/Documentation/devicetree/bindings/i2c/i2c-mux.yaml b/Documentation/devicetree/bindings/i2c/i2c-mux.yaml
new file mode 100644
index 000000000000..3aa4d84a6610
--- /dev/null
+++ b/Documentation/devicetree/bindings/i2c/i2c-mux.yaml
@@ -0,0 +1,87 @@
+# 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 <[email protected]>
+
+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>;
+ };
+ };
+ };
+ };
+...
--
2.27.0
On Tue, May 18, 2021 at 8:39 PM Laurent Pinchart
<[email protected]> wrote:
>
> Hi Rob,
>
> Thank you for the patch.
>
> On Tue, May 18, 2021 at 06:28:56PM -0500, Rob Herring wrote:
> > As some of the example I2C devices don't have schemas yet, change them to
> > ones that do.
> >
> > Cc: Peter Rosin <[email protected]>
> > Signed-off-by: Rob Herring <[email protected]>
> > ---
> > .../bindings/i2c/i2c-demux-pinctrl.txt | 2 +-
> > .../devicetree/bindings/i2c/i2c-mux-gpio.txt | 4 +-
> > .../devicetree/bindings/i2c/i2c-mux-gpmux.txt | 99 --------------
> > .../bindings/i2c/i2c-mux-gpmux.yaml | 124 ++++++++++++++++++
> > .../bindings/i2c/i2c-mux-ltc4306.txt | 4 +-
> > .../bindings/i2c/i2c-mux-pinctrl.txt | 4 +-
> > .../devicetree/bindings/i2c/i2c-mux-reg.txt | 4 +-
> > .../devicetree/bindings/i2c/i2c-mux.txt | 73 -----------
> > .../devicetree/bindings/i2c/i2c-mux.yaml | 87 ++++++++++++
> > 9 files changed, 220 insertions(+), 181 deletions(-)
> > delete mode 100644 Documentation/devicetree/bindings/i2c/i2c-mux-gpmux.txt
> > create mode 100644 Documentation/devicetree/bindings/i2c/i2c-mux-gpmux.yaml
> > delete mode 100644 Documentation/devicetree/bindings/i2c/i2c-mux.txt
> > create mode 100644 Documentation/devicetree/bindings/i2c/i2c-mux.yaml
> >
> > diff --git a/Documentation/devicetree/bindings/i2c/i2c-demux-pinctrl.txt b/Documentation/devicetree/bindings/i2c/i2c-demux-pinctrl.txt
> > index 81b5d55086fa..86b2e433a969 100644
> > --- a/Documentation/devicetree/bindings/i2c/i2c-demux-pinctrl.txt
> > +++ b/Documentation/devicetree/bindings/i2c/i2c-demux-pinctrl.txt
> > @@ -27,7 +27,7 @@ Required properties:
> > - 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.txt in this
> > +Furthermore, I2C mux properties and child nodes. See i2c-mux.yaml in this
> > directory.
> >
> > Example:
> > diff --git a/Documentation/devicetree/bindings/i2c/i2c-mux-gpio.txt b/Documentation/devicetree/bindings/i2c/i2c-mux-gpio.txt
> > index 21da3ecbb370..e00d2b9e957a 100644
> > --- a/Documentation/devicetree/bindings/i2c/i2c-mux-gpio.txt
> > +++ b/Documentation/devicetree/bindings/i2c/i2c-mux-gpio.txt
> > @@ -22,8 +22,8 @@ Required properties:
> > - i2c-parent: The phandle of the I2C bus that this multiplexer's master-side
> > port is connected to.
> > - mux-gpios: list of gpios used to control the muxer
> > -* Standard I2C mux properties. See i2c-mux.txt in this directory.
> > -* I2C child bus nodes. 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.yaml in this directory.
> >
> > Optional properties:
> > - idle-state: value to set the muxer to when idle. When no value is
> > diff --git a/Documentation/devicetree/bindings/i2c/i2c-mux-gpmux.txt b/Documentation/devicetree/bindings/i2c/i2c-mux-gpmux.txt
> > deleted file mode 100644
> > index 057083a8ba17..000000000000
> > --- a/Documentation/devicetree/bindings/i2c/i2c-mux-gpmux.txt
> > +++ /dev/null
> > @@ -1,99 +0,0 @@
> > -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>;
> > - };
> > - };
> > - };
> > diff --git a/Documentation/devicetree/bindings/i2c/i2c-mux-gpmux.yaml b/Documentation/devicetree/bindings/i2c/i2c-mux-gpmux.yaml
> > new file mode 100644
> > index 000000000000..3e6ea59aea68
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/i2c/i2c-mux-gpmux.yaml
> > @@ -0,0 +1,124 @@
> > +# 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 <[email protected]>
> > +
> > +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>;
> > + };
> > + };
> > + };
> > +...
> > diff --git a/Documentation/devicetree/bindings/i2c/i2c-mux-ltc4306.txt b/Documentation/devicetree/bindings/i2c/i2c-mux-ltc4306.txt
> > index 8b1e49cdce3f..29c4550c9782 100644
> > --- a/Documentation/devicetree/bindings/i2c/i2c-mux-ltc4306.txt
> > +++ b/Documentation/devicetree/bindings/i2c/i2c-mux-ltc4306.txt
> > @@ -8,8 +8,8 @@ Required Properties:
> >
> > The following required properties are defined externally:
> >
> > - - Standard I2C mux properties. See i2c-mux.txt in this directory.
> > - - I2C child bus nodes. 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.yaml in this directory.
> >
> > Optional Properties:
> >
> > diff --git a/Documentation/devicetree/bindings/i2c/i2c-mux-pinctrl.txt b/Documentation/devicetree/bindings/i2c/i2c-mux-pinctrl.txt
> > index 33119a98e144..997a287ed3f6 100644
> > --- a/Documentation/devicetree/bindings/i2c/i2c-mux-pinctrl.txt
> > +++ b/Documentation/devicetree/bindings/i2c/i2c-mux-pinctrl.txt
> > @@ -28,9 +28,9 @@ Also required are:
> > * Standard pinctrl properties that specify the pin mux state for each child
> > 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
> > will be created. I2C child bus numbers are assigned based on the index into
> > diff --git a/Documentation/devicetree/bindings/i2c/i2c-mux-reg.txt b/Documentation/devicetree/bindings/i2c/i2c-mux-reg.txt
> > index de00d7fc450b..b9d9755e4172 100644
> > --- a/Documentation/devicetree/bindings/i2c/i2c-mux-reg.txt
> > +++ b/Documentation/devicetree/bindings/i2c/i2c-mux-reg.txt
> > @@ -7,8 +7,8 @@ Required properties:
> > - compatible: i2c-mux-reg
> > - i2c-parent: The phandle of the I2C bus that this multiplexer's master-side
> > port is connected to.
> > -* Standard I2C mux properties. See i2c-mux.txt in this directory.
> > -* I2C child bus nodes. 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.yaml in this directory.
> >
> > Optional properties:
> > - reg: this pair of <offset size> specifies the register to control the mux.
> > diff --git a/Documentation/devicetree/bindings/i2c/i2c-mux.txt b/Documentation/devicetree/bindings/i2c/i2c-mux.txt
> > deleted file mode 100644
> > index b38f58a1c878..000000000000
> > --- a/Documentation/devicetree/bindings/i2c/i2c-mux.txt
> > +++ /dev/null
> > @@ -1,73 +0,0 @@
> > -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;
> > - };
> > - };
> > - };
> > diff --git a/Documentation/devicetree/bindings/i2c/i2c-mux.yaml b/Documentation/devicetree/bindings/i2c/i2c-mux.yaml
> > new file mode 100644
> > index 000000000000..3aa4d84a6610
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/i2c/i2c-mux.yaml
> > @@ -0,0 +1,87 @@
> > +# 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 <[email protected]>
> > +
> > +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.
>
> As I understand this, it means that child nodes corresponding to child
> buses can be either direct children of the I2C mux node, or grouped in a
> i2c-mux node (the same way we optionally group the 'port' nodes in a
> 'ports' node). This doesn't seem to be supported by the bindings below.
I take this as like any MFD. If i2c mux is one of the functions, we'll
have a child node for it. In that case, that device's binding will
define the 'i2c-mux' node and then reference this schema. The fact
that this mentions other nodes being I2C devices is not important and
a somewhat confusing detail. I considered just removing as I don't
think the paragraph is all that useful, but I try not to delete too
much from existing bindings.
Rob
Hi Rob,
Thank you for the patch.
On Tue, May 18, 2021 at 06:28:56PM -0500, Rob Herring wrote:
> As some of the example I2C devices don't have schemas yet, change them to
> ones that do.
>
> Cc: Peter Rosin <[email protected]>
> Signed-off-by: Rob Herring <[email protected]>
> ---
> .../bindings/i2c/i2c-demux-pinctrl.txt | 2 +-
> .../devicetree/bindings/i2c/i2c-mux-gpio.txt | 4 +-
> .../devicetree/bindings/i2c/i2c-mux-gpmux.txt | 99 --------------
> .../bindings/i2c/i2c-mux-gpmux.yaml | 124 ++++++++++++++++++
> .../bindings/i2c/i2c-mux-ltc4306.txt | 4 +-
> .../bindings/i2c/i2c-mux-pinctrl.txt | 4 +-
> .../devicetree/bindings/i2c/i2c-mux-reg.txt | 4 +-
> .../devicetree/bindings/i2c/i2c-mux.txt | 73 -----------
> .../devicetree/bindings/i2c/i2c-mux.yaml | 87 ++++++++++++
> 9 files changed, 220 insertions(+), 181 deletions(-)
> delete mode 100644 Documentation/devicetree/bindings/i2c/i2c-mux-gpmux.txt
> create mode 100644 Documentation/devicetree/bindings/i2c/i2c-mux-gpmux.yaml
> delete mode 100644 Documentation/devicetree/bindings/i2c/i2c-mux.txt
> create mode 100644 Documentation/devicetree/bindings/i2c/i2c-mux.yaml
>
> diff --git a/Documentation/devicetree/bindings/i2c/i2c-demux-pinctrl.txt b/Documentation/devicetree/bindings/i2c/i2c-demux-pinctrl.txt
> index 81b5d55086fa..86b2e433a969 100644
> --- a/Documentation/devicetree/bindings/i2c/i2c-demux-pinctrl.txt
> +++ b/Documentation/devicetree/bindings/i2c/i2c-demux-pinctrl.txt
> @@ -27,7 +27,7 @@ Required properties:
> - 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.txt in this
> +Furthermore, I2C mux properties and child nodes. See i2c-mux.yaml in this
> directory.
>
> Example:
> diff --git a/Documentation/devicetree/bindings/i2c/i2c-mux-gpio.txt b/Documentation/devicetree/bindings/i2c/i2c-mux-gpio.txt
> index 21da3ecbb370..e00d2b9e957a 100644
> --- a/Documentation/devicetree/bindings/i2c/i2c-mux-gpio.txt
> +++ b/Documentation/devicetree/bindings/i2c/i2c-mux-gpio.txt
> @@ -22,8 +22,8 @@ Required properties:
> - i2c-parent: The phandle of the I2C bus that this multiplexer's master-side
> port is connected to.
> - mux-gpios: list of gpios used to control the muxer
> -* Standard I2C mux properties. See i2c-mux.txt in this directory.
> -* I2C child bus nodes. 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.yaml in this directory.
>
> Optional properties:
> - idle-state: value to set the muxer to when idle. When no value is
> diff --git a/Documentation/devicetree/bindings/i2c/i2c-mux-gpmux.txt b/Documentation/devicetree/bindings/i2c/i2c-mux-gpmux.txt
> deleted file mode 100644
> index 057083a8ba17..000000000000
> --- a/Documentation/devicetree/bindings/i2c/i2c-mux-gpmux.txt
> +++ /dev/null
> @@ -1,99 +0,0 @@
> -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>;
> - };
> - };
> - };
> diff --git a/Documentation/devicetree/bindings/i2c/i2c-mux-gpmux.yaml b/Documentation/devicetree/bindings/i2c/i2c-mux-gpmux.yaml
> new file mode 100644
> index 000000000000..3e6ea59aea68
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/i2c/i2c-mux-gpmux.yaml
> @@ -0,0 +1,124 @@
> +# 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 <[email protected]>
> +
> +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>;
> + };
> + };
> + };
> +...
> diff --git a/Documentation/devicetree/bindings/i2c/i2c-mux-ltc4306.txt b/Documentation/devicetree/bindings/i2c/i2c-mux-ltc4306.txt
> index 8b1e49cdce3f..29c4550c9782 100644
> --- a/Documentation/devicetree/bindings/i2c/i2c-mux-ltc4306.txt
> +++ b/Documentation/devicetree/bindings/i2c/i2c-mux-ltc4306.txt
> @@ -8,8 +8,8 @@ Required Properties:
>
> The following required properties are defined externally:
>
> - - Standard I2C mux properties. See i2c-mux.txt in this directory.
> - - I2C child bus nodes. 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.yaml in this directory.
>
> Optional Properties:
>
> diff --git a/Documentation/devicetree/bindings/i2c/i2c-mux-pinctrl.txt b/Documentation/devicetree/bindings/i2c/i2c-mux-pinctrl.txt
> index 33119a98e144..997a287ed3f6 100644
> --- a/Documentation/devicetree/bindings/i2c/i2c-mux-pinctrl.txt
> +++ b/Documentation/devicetree/bindings/i2c/i2c-mux-pinctrl.txt
> @@ -28,9 +28,9 @@ Also required are:
> * Standard pinctrl properties that specify the pin mux state for each child
> 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
> will be created. I2C child bus numbers are assigned based on the index into
> diff --git a/Documentation/devicetree/bindings/i2c/i2c-mux-reg.txt b/Documentation/devicetree/bindings/i2c/i2c-mux-reg.txt
> index de00d7fc450b..b9d9755e4172 100644
> --- a/Documentation/devicetree/bindings/i2c/i2c-mux-reg.txt
> +++ b/Documentation/devicetree/bindings/i2c/i2c-mux-reg.txt
> @@ -7,8 +7,8 @@ Required properties:
> - compatible: i2c-mux-reg
> - i2c-parent: The phandle of the I2C bus that this multiplexer's master-side
> port is connected to.
> -* Standard I2C mux properties. See i2c-mux.txt in this directory.
> -* I2C child bus nodes. 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.yaml in this directory.
>
> Optional properties:
> - reg: this pair of <offset size> specifies the register to control the mux.
> diff --git a/Documentation/devicetree/bindings/i2c/i2c-mux.txt b/Documentation/devicetree/bindings/i2c/i2c-mux.txt
> deleted file mode 100644
> index b38f58a1c878..000000000000
> --- a/Documentation/devicetree/bindings/i2c/i2c-mux.txt
> +++ /dev/null
> @@ -1,73 +0,0 @@
> -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;
> - };
> - };
> - };
> diff --git a/Documentation/devicetree/bindings/i2c/i2c-mux.yaml b/Documentation/devicetree/bindings/i2c/i2c-mux.yaml
> new file mode 100644
> index 000000000000..3aa4d84a6610
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/i2c/i2c-mux.yaml
> @@ -0,0 +1,87 @@
> +# 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 <[email protected]>
> +
> +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.
As I understand this, it means that child nodes corresponding to child
buses can be either direct children of the I2C mux node, or grouped in a
i2c-mux node (the same way we optionally group the 'port' nodes in a
'ports' node). This doesn't seem to be supported by the bindings below.
> +
> +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.
I'd add the missing * while at it.
> + */
> + 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>;
> + };
> + };
> + };
> + };
> +...
--
Regards,
Laurent Pinchart
Hi Rob,
One more comment.
On Wed, May 19, 2021 at 04:39:11AM +0300, Laurent Pinchart wrote:
> On Tue, May 18, 2021 at 06:28:56PM -0500, Rob Herring wrote:
> > As some of the example I2C devices don't have schemas yet, change them to
> > ones that do.
> >
> > Cc: Peter Rosin <[email protected]>
> > Signed-off-by: Rob Herring <[email protected]>
> > ---
> > .../bindings/i2c/i2c-demux-pinctrl.txt | 2 +-
> > .../devicetree/bindings/i2c/i2c-mux-gpio.txt | 4 +-
> > .../devicetree/bindings/i2c/i2c-mux-gpmux.txt | 99 --------------
> > .../bindings/i2c/i2c-mux-gpmux.yaml | 124 ++++++++++++++++++
> > .../bindings/i2c/i2c-mux-ltc4306.txt | 4 +-
> > .../bindings/i2c/i2c-mux-pinctrl.txt | 4 +-
> > .../devicetree/bindings/i2c/i2c-mux-reg.txt | 4 +-
> > .../devicetree/bindings/i2c/i2c-mux.txt | 73 -----------
> > .../devicetree/bindings/i2c/i2c-mux.yaml | 87 ++++++++++++
> > 9 files changed, 220 insertions(+), 181 deletions(-)
> > delete mode 100644 Documentation/devicetree/bindings/i2c/i2c-mux-gpmux.txt
> > create mode 100644 Documentation/devicetree/bindings/i2c/i2c-mux-gpmux.yaml
> > delete mode 100644 Documentation/devicetree/bindings/i2c/i2c-mux.txt
> > create mode 100644 Documentation/devicetree/bindings/i2c/i2c-mux.yaml
> >
> > diff --git a/Documentation/devicetree/bindings/i2c/i2c-demux-pinctrl.txt b/Documentation/devicetree/bindings/i2c/i2c-demux-pinctrl.txt
> > index 81b5d55086fa..86b2e433a969 100644
> > --- a/Documentation/devicetree/bindings/i2c/i2c-demux-pinctrl.txt
> > +++ b/Documentation/devicetree/bindings/i2c/i2c-demux-pinctrl.txt
> > @@ -27,7 +27,7 @@ Required properties:
> > - 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.txt in this
> > +Furthermore, I2C mux properties and child nodes. See i2c-mux.yaml in this
> > directory.
> >
> > Example:
> > diff --git a/Documentation/devicetree/bindings/i2c/i2c-mux-gpio.txt b/Documentation/devicetree/bindings/i2c/i2c-mux-gpio.txt
> > index 21da3ecbb370..e00d2b9e957a 100644
> > --- a/Documentation/devicetree/bindings/i2c/i2c-mux-gpio.txt
> > +++ b/Documentation/devicetree/bindings/i2c/i2c-mux-gpio.txt
> > @@ -22,8 +22,8 @@ Required properties:
> > - i2c-parent: The phandle of the I2C bus that this multiplexer's master-side
> > port is connected to.
> > - mux-gpios: list of gpios used to control the muxer
> > -* Standard I2C mux properties. See i2c-mux.txt in this directory.
> > -* I2C child bus nodes. 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.yaml in this directory.
> >
> > Optional properties:
> > - idle-state: value to set the muxer to when idle. When no value is
> > diff --git a/Documentation/devicetree/bindings/i2c/i2c-mux-gpmux.txt b/Documentation/devicetree/bindings/i2c/i2c-mux-gpmux.txt
> > deleted file mode 100644
> > index 057083a8ba17..000000000000
> > --- a/Documentation/devicetree/bindings/i2c/i2c-mux-gpmux.txt
> > +++ /dev/null
> > @@ -1,99 +0,0 @@
> > -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>;
> > - };
> > - };
> > - };
> > diff --git a/Documentation/devicetree/bindings/i2c/i2c-mux-gpmux.yaml b/Documentation/devicetree/bindings/i2c/i2c-mux-gpmux.yaml
> > new file mode 100644
> > index 000000000000..3e6ea59aea68
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/i2c/i2c-mux-gpmux.yaml
> > @@ -0,0 +1,124 @@
> > +# 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 <[email protected]>
> > +
> > +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
I know it comes from the original .txt file, but '+' is a weird marker
for a list. Could we replace them with '-' while at it ?
> > +
> > + 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>;
> > + };
> > + };
> > + };
> > +...
> > diff --git a/Documentation/devicetree/bindings/i2c/i2c-mux-ltc4306.txt b/Documentation/devicetree/bindings/i2c/i2c-mux-ltc4306.txt
> > index 8b1e49cdce3f..29c4550c9782 100644
> > --- a/Documentation/devicetree/bindings/i2c/i2c-mux-ltc4306.txt
> > +++ b/Documentation/devicetree/bindings/i2c/i2c-mux-ltc4306.txt
> > @@ -8,8 +8,8 @@ Required Properties:
> >
> > The following required properties are defined externally:
> >
> > - - Standard I2C mux properties. See i2c-mux.txt in this directory.
> > - - I2C child bus nodes. 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.yaml in this directory.
> >
> > Optional Properties:
> >
> > diff --git a/Documentation/devicetree/bindings/i2c/i2c-mux-pinctrl.txt b/Documentation/devicetree/bindings/i2c/i2c-mux-pinctrl.txt
> > index 33119a98e144..997a287ed3f6 100644
> > --- a/Documentation/devicetree/bindings/i2c/i2c-mux-pinctrl.txt
> > +++ b/Documentation/devicetree/bindings/i2c/i2c-mux-pinctrl.txt
> > @@ -28,9 +28,9 @@ Also required are:
> > * Standard pinctrl properties that specify the pin mux state for each child
> > 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
> > will be created. I2C child bus numbers are assigned based on the index into
> > diff --git a/Documentation/devicetree/bindings/i2c/i2c-mux-reg.txt b/Documentation/devicetree/bindings/i2c/i2c-mux-reg.txt
> > index de00d7fc450b..b9d9755e4172 100644
> > --- a/Documentation/devicetree/bindings/i2c/i2c-mux-reg.txt
> > +++ b/Documentation/devicetree/bindings/i2c/i2c-mux-reg.txt
> > @@ -7,8 +7,8 @@ Required properties:
> > - compatible: i2c-mux-reg
> > - i2c-parent: The phandle of the I2C bus that this multiplexer's master-side
> > port is connected to.
> > -* Standard I2C mux properties. See i2c-mux.txt in this directory.
> > -* I2C child bus nodes. 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.yaml in this directory.
> >
> > Optional properties:
> > - reg: this pair of <offset size> specifies the register to control the mux.
> > diff --git a/Documentation/devicetree/bindings/i2c/i2c-mux.txt b/Documentation/devicetree/bindings/i2c/i2c-mux.txt
> > deleted file mode 100644
> > index b38f58a1c878..000000000000
> > --- a/Documentation/devicetree/bindings/i2c/i2c-mux.txt
> > +++ /dev/null
> > @@ -1,73 +0,0 @@
> > -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;
> > - };
> > - };
> > - };
> > diff --git a/Documentation/devicetree/bindings/i2c/i2c-mux.yaml b/Documentation/devicetree/bindings/i2c/i2c-mux.yaml
> > new file mode 100644
> > index 000000000000..3aa4d84a6610
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/i2c/i2c-mux.yaml
> > @@ -0,0 +1,87 @@
> > +# 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 <[email protected]>
> > +
> > +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.
>
> As I understand this, it means that child nodes corresponding to child
> buses can be either direct children of the I2C mux node, or grouped in a
> i2c-mux node (the same way we optionally group the 'port' nodes in a
> 'ports' node). This doesn't seem to be supported by the bindings below.
>
> > +
> > +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.
>
> I'd add the missing * while at it.
>
> > + */
> > + 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>;
> > + };
> > + };
> > + };
> > + };
> > +...
--
Regards,
Laurent Pinchart