linux-kernel - [PATCH v3 6/7] dt-bindings: i2c: i2c-mux-simple: document i2c-mux-simple bindings

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <1479734235-18837-7-git-send-email-peda@axentia.se>
Date:   Mon, 21 Nov 2016 14:17:14 +0100
From:   Peter Rosin <peda@...ntia.se>
To:     <linux-kernel@...r.kernel.org>
CC:     Peter Rosin <peda@...ntia.se>, Wolfram Sang <wsa@...-dreams.de>,
        "Rob Herring" <robh+dt@...nel.org>,
        Mark Rutland <mark.rutland@....com>,
        "Jonathan Cameron" <jic23@...nel.org>,
        Hartmut Knaack <knaack.h@....de>,
        "Lars-Peter Clausen" <lars@...afoo.de>,
        Peter Meerwald-Stadler <pmeerw@...erw.net>,
        Jonathan Corbet <corbet@....net>,
        Arnd Bergmann <arnd@...db.de>,
        "Greg Kroah-Hartman" <gregkh@...uxfoundation.org>,
        <linux-i2c@...r.kernel.org>, <devicetree@...r.kernel.org>,
        <linux-iio@...r.kernel.org>, <linux-doc@...r.kernel.org>
Subject: [PATCH v3 6/7] dt-bindings: i2c: i2c-mux-simple: document i2c-mux-simple bindings

Signed-off-by: Peter Rosin <peda@...ntia.se>
---
 .../devicetree/bindings/i2c/i2c-mux-simple.txt     | 76 ++++++++++++++++++++++
 1 file changed, 76 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/i2c/i2c-mux-simple.txt

diff --git a/Documentation/devicetree/bindings/i2c/i2c-mux-simple.txt b/Documentation/devicetree/bindings/i2c/i2c-mux-simple.txt
new file mode 100644
index 000000000000..decfd742b297
--- /dev/null
+++ b/Documentation/devicetree/bindings/i2c/i2c-mux-simple.txt
@@ -0,0 +1,76 @@
+Simple 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-simple,mux-locked or i2c-mux-simple,parent-locked
+- 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. The sub-bus number
+  is also the mux-controller state described in ../misc/mux-controller.txt
+
+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 {
+		compatible = "mux-gpio";
+
+		mux-gpios = <&pioA 0 GPIO_ACTIVE_HIGH>,
+			    <&pioA 1 GPIO_ACTIVE_HIGH>;
+
+		i2c-mux {
+			compatible = "i2c-mux-simple,mux-locked";
+			i2c-parent = <&i2c1>;
+
+			#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>;
+				};
+			};
+		};
+	};
-- 
2.1.4