i2c: mv64xxx: Fix clock resource by adding an optional bus clock

On Armada 7K/8K we need to explicitly enable the bus clock. The bus clock
is optional because not all the SoCs need them but at least for Armada
7K/8K it is actually mandatory.

The binding documentation is updating accordingly.

Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

1 files changed, 20 insertions, 0 deletions

diff --git a/Documentation/devicetree/bindings/i2c/i2c-mv64xxx.txt b/Documentation/devicetree/bindings/i2c/i2c-mv64xxx.txt
index 5c30026921ae..0ffe65a316ae 100644
--- a/Documentation/devicetree/bindings/i2c/i2c-mv64xxx.txt
+++ b/Documentation/devicetree/bindings/i2c/i2c-mv64xxx.txt
@@ -25,6 +25,15 @@ default frequency is 100kHz
                      whenever you're using the "allwinner,sun6i-a31-i2c"
                      compatible.
 
+ - clocks:	   : pointers to the reference clocks for this device, the
+		     first one is the one used for the clock on the i2c bus,
+		     the second one is the clock used to acces the registers
+		     of the controller
+
+ - clock-names	   : names of used clocks, mandatory if the second clock is
+		     used, the name must be "core", and "reg" (the latter is
+		     only for Armada 7K/8K).
+
 Examples:
 
 	i2c@11000 {
@@ -42,3 +51,14 @@ For the Armada XP:
 		interrupts = <29>;
 		clock-frequency = <100000>;
 	};
+
+For the Armada 7040:
+
+	i2c@701000 {
+		compatible = "marvell,mv78230-i2c";
+		reg = <0x701000 0x20>;
+		interrupts = <29>;
+		clock-frequency = <100000>;
+		clock-names = "core", "reg";
+		clocks = <&core_clock>, <&reg_clock>;
+	};