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authorLinus Torvalds <torvalds@linux-foundation.org>2012-12-18 16:51:10 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2012-12-18 16:51:10 -0800
commit752451f01c4567b506bf4343082682dbb8fb30dd (patch)
treeec2ec2989c93e567952ddc1ec879013aa2704f0a /Documentation
parent673ab8783b596cda5b616b317b1a1b47480c66fd (diff)
parent972deb4f49b5b6703d9c6117ba0aeda2180d4447 (diff)
downloadlinux-752451f01c4567b506bf4343082682dbb8fb30dd.tar.gz
Merge branch 'i2c-embedded/for-next' of git://git.pengutronix.de/git/wsa/linux
Pull i2c-embedded changes from Wolfram Sang:
 - CBUS driver (an I2C variant)
 - continued rework of the omap driver
 - s3c2410 gets lots of fixes and gains pinctrl support
 - at91 gains DMA support
 - the GPIO muxer gains devicetree probing
 - typical fixes and additions all over

* 'i2c-embedded/for-next' of git://git.pengutronix.de/git/wsa/linux: (45 commits)
  i2c: omap: Remove the OMAP_I2C_FLAG_RESET_REGS_POSTIDLE flag
  i2c: at91: add dma support
  i2c: at91: change struct members indentation
  i2c: at91: fix compilation warning
  i2c: mxs: Do not disable the I2C SMBus quick mode
  i2c: mxs: Handle i2c DMA failure properly
  i2c: s3c2410: Remove recently introduced performance overheads
  i2c: ocores: Move grlib set/get functions into #ifdef CONFIG_OF block
  i2c: s3c2410: Add fix for i2c suspend/resume
  i2c: s3c2410: Fix code to free gpios
  i2c: i2c-cbus-gpio: introduce driver
  i2c: ocores: Add support for the GRLIB port of the controller and use function pointers for getreg and setreg functions
  i2c: ocores: Add irq support for sparc
  i2c: omap: Move the remove constraint
  ARM: dts: cfa10049: Add the i2c muxer buses to the CFA-10049
  i2c: s3c2410: do not special case HDMIPHY stuck bus detection
  i2c: s3c2410: use exponential back off while polling for bus idle
  i2c: s3c2410: do not generate STOP for QUIRK_HDMIPHY
  i2c: s3c2410: grab adapter lock while changing i2c clock
  i2c: s3c2410: Add support for pinctrl
  ...
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/devicetree/bindings/i2c/i2c-cbus-gpio.txt27
-rw-r--r--Documentation/devicetree/bindings/i2c/i2c-mux-gpio.txt81
-rw-r--r--Documentation/devicetree/bindings/i2c/i2c-ocores.txt2
-rw-r--r--Documentation/devicetree/bindings/i2c/i2c-s3c2410.txt20
4 files changed, 125 insertions, 5 deletions
diff --git a/Documentation/devicetree/bindings/i2c/i2c-cbus-gpio.txt b/Documentation/devicetree/bindings/i2c/i2c-cbus-gpio.txt
new file mode 100644
index 000000000000..8ce9cd2855b5
--- /dev/null
+++ b/Documentation/devicetree/bindings/i2c/i2c-cbus-gpio.txt
@@ -0,0 +1,27 @@
+Device tree bindings for i2c-cbus-gpio driver
+
+Required properties:
+	- compatible = "i2c-cbus-gpio";
+	- gpios: clk, dat, sel
+	- #address-cells = <1>;
+	- #size-cells = <0>;
+
+Optional properties:
+	- child nodes conforming to i2c bus binding
+
+Example:
+
+i2c@0 {
+	compatible = "i2c-cbus-gpio";
+	gpios = <&gpio 66 0 /* clk */
+		 &gpio 65 0 /* dat */
+		 &gpio 64 0 /* sel */
+		>;
+	#address-cells = <1>;
+	#size-cells = <0>;
+
+	retu-mfd: retu@1 {
+		compatible = "retu-mfd";
+		reg = <0x1>;
+	};
+};
diff --git a/Documentation/devicetree/bindings/i2c/i2c-mux-gpio.txt b/Documentation/devicetree/bindings/i2c/i2c-mux-gpio.txt
new file mode 100644
index 000000000000..66709a825541
--- /dev/null
+++ b/Documentation/devicetree/bindings/i2c/i2c-mux-gpio.txt
@@ -0,0 +1,81 @@
+GPIO-based I2C Bus Mux
+
+This binding describes an I2C bus multiplexer that uses GPIOs to
+route the I2C signals.
+
+                                  +-----+  +-----+
+                                  | dev |  | dev |
+    +------------+                +-----+  +-----+
+    | SoC        |                   |        |
+    |            |          /--------+--------+
+    |   +------+ |  +------+    child bus A, on GPIO value set to 0
+    |   | I2C  |-|--| Mux  |
+    |   +------+ |  +--+---+    child bus B, on GPIO value set to 1
+    |            |     |    \----------+--------+--------+
+    |   +------+ |     |               |        |        |
+    |   | GPIO |-|-----+            +-----+  +-----+  +-----+
+    |   +------+ |                  | dev |  | dev |  | dev |
+    +------------+                  +-----+  +-----+  +-----+
+
+Required properties:
+- compatible: i2c-mux-gpio
+- 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 mux.txt in this directory.
+* I2C child bus nodes. See mux.txt in this directory.
+
+Optional properties:
+- idle-state: value to set the muxer to when idle. When no value is
+  given, it defaults to the last value used.
+
+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 revelant node's reg property will be output using the list of
+GPIOs, the first in the list holding the least-significant value.
+
+If an idle state is defined, using the idle-state (optional) property,
+whenever an access is not being made to a device on a child bus, the
+GPIOs will be set according to the idle value.
+
+If an idle state is not defined, the most recently used value will be
+left programmed into hardware whenever no access is being made to a
+device on a child bus.
+
+Example:
+	i2cmux {
+		compatible = "i2c-mux-gpio";
+		#address-cells = <1>;
+		#size-cells = <0>;
+		mux-gpios = <&gpio1 22 0 &gpio1 23 0>;
+		i2c-parent = <&i2c1>;
+
+		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-ocores.txt b/Documentation/devicetree/bindings/i2c/i2c-ocores.txt
index c15781f4dc8c..1637c298a1b3 100644
--- a/Documentation/devicetree/bindings/i2c/i2c-ocores.txt
+++ b/Documentation/devicetree/bindings/i2c/i2c-ocores.txt
@@ -1,7 +1,7 @@
 Device tree configuration for i2c-ocores
 
 Required properties:
-- compatible      : "opencores,i2c-ocores"
+- compatible      : "opencores,i2c-ocores" or "aeroflexgaisler,i2cmst"
 - reg             : bus address start and address range size of device
 - interrupts      : interrupt number
 - clock-frequency : frequency of bus clock in Hz
diff --git a/Documentation/devicetree/bindings/i2c/i2c-s3c2410.txt b/Documentation/devicetree/bindings/i2c/i2c-s3c2410.txt
index b6cb5a12c672..e9611ace8792 100644
--- a/Documentation/devicetree/bindings/i2c/i2c-s3c2410.txt
+++ b/Documentation/devicetree/bindings/i2c/i2c-s3c2410.txt
@@ -13,11 +13,17 @@ Required properties:
   - interrupts: interrupt number to the cpu.
   - samsung,i2c-sda-delay: Delay (in ns) applied to data line (SDA) edges.
 
+Required for all cases except "samsung,s3c2440-hdmiphy-i2c":
+  - Samsung GPIO variant (deprecated):
+    - gpios: The order of the gpios should be the following: <SDA, SCL>.
+      The gpio specifier depends on the gpio controller. Required in all
+      cases except for "samsung,s3c2440-hdmiphy-i2c" whose input/output
+      lines are permanently wired to the respective clienta
+  - Pinctrl variant (preferred, if available):
+    - pinctrl-0: Pin control group to be used for this controller.
+    - pinctrl-names: Should contain only one value - "default".
+
 Optional properties:
-  - gpios: The order of the gpios should be the following: <SDA, SCL>.
-    The gpio specifier depends on the gpio controller. Required in all
-    cases except for "samsung,s3c2440-hdmiphy-i2c" whose input/output
-    lines are permanently wired to the respective client
   - samsung,i2c-slave-addr: Slave address in multi-master enviroment. If not
     specified, default value is 0.
   - samsung,i2c-max-bus-freq: Desired frequency in Hz of the bus. If not
@@ -31,8 +37,14 @@ Example:
 		interrupts = <345>;
 		samsung,i2c-sda-delay = <100>;
 		samsung,i2c-max-bus-freq = <100000>;
+		/* Samsung GPIO variant begins here */
 		gpios = <&gpd1 2 0 /* SDA */
 			 &gpd1 3 0 /* SCL */>;
+		/* Samsung GPIO variant ends here */
+		/* Pinctrl variant begins here */
+		pinctrl-0 = <&i2c3_bus>;
+		pinctrl-names = "default";
+		/* Pinctrl variant ends here */
 		#address-cells = <1>;
 		#size-cells = <0>;