clk: shmobile: Add DIV6 clock support

DIV6 clocks are divider gate clocks controlled through a single
register. The divider is expressed on 6 bits, hence the name, and can
take values from 1/1 to 1/64.

Those clocks are found on Renesas ARM SoCs.

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Mike Turquette <mturquette@linaro.org>

1 files changed, 28 insertions, 0 deletions

diff --git a/Documentation/devicetree/bindings/clock/renesas,cpg-div6-clocks.txt b/Documentation/devicetree/bindings/clock/renesas,cpg-div6-clocks.txt
new file mode 100644
index 0000000..952e373
--- /dev/null
+++ b/Documentation/devicetree/bindings/clock/renesas,cpg-div6-clocks.txt
@@ -0,0 +1,28 @@
+* Renesas CPG DIV6 Clock
+
+The CPG DIV6 clocks are variable factor clocks provided by the Clock Pulse
+Generator (CPG). They clock input is divided by a configurable factor from 1
+to 64.
+
+Required Properties:
+
+  - compatible: Must be one of the following
+    - "renesas,r8a7790-div6-clock" for R8A7790 (R-Car H2) DIV6 clocks
+    - "renesas,r8a7791-div6-clock" for R8A7791 (R-Car M2) DIV6 clocks
+    - "renesas,cpg-div6-clock" for generic DIV6 clocks
+  - reg: Base address and length of the memory resource used by the DIV6 clock
+  - clocks: Reference to the parent clock
+  - #clock-cells: Must be 0
+  - clock-output-names: The name of the clock as a free-form string
+
+
+Example
+-------
+
+	sd2_clk: sd2_clk@e6150078 {
+		compatible = "renesas,r8a7790-div6-clock", "renesas,cpg-div6-clock";
+		reg = <0 0xe6150078 0 4>;
+		clocks = <&pll1_div2_clk>;
+		#clock-cells = <0>;
+		clock-output-names = "sd2";
+	};