clk: shmobile: Add R-Car Gen2 clocks support

The R-Car Gen2 SoCs (R8A7790 and R8A7791) have several clocks that are
too custom to be supported in a generic driver. Those clocks can be
divided in two categories:

- Fixed rate clocks with multiplier and divisor set according to boot
  mode configuration

- Custom divider clocks with SoC-specific divider values

This driver supports both.

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

1 files changed, 32 insertions, 0 deletions

diff --git a/Documentation/devicetree/bindings/clock/renesas,rcar-gen2-cpg-clocks.txt b/Documentation/devicetree/bindings/clock/renesas,rcar-gen2-cpg-clocks.txt
new file mode 100644
index 000000000000..7b41c2fe54db
--- /dev/null
+++ b/Documentation/devicetree/bindings/clock/renesas,rcar-gen2-cpg-clocks.txt
@@ -0,0 +1,32 @@
+* Renesas R-Car Gen2 Clock Pulse Generator (CPG)
+
+The CPG generates core clocks for the R-Car Gen2 SoCs. It includes three PLLs
+and several fixed ratio dividers.
+
+Required Properties:
+
+  - compatible: Must be one of
+    - "renesas,r8a7790-cpg-clocks" for the r8a7790 CPG
+    - "renesas,r8a7791-cpg-clocks" for the r8a7791 CPG
+    - "renesas,rcar-gen2-cpg-clocks" for the generic R-Car Gen2 CPG
+
+  - reg: Base address and length of the memory resource used by the CPG
+
+  - clocks: Reference to the parent clock
+  - #clock-cells: Must be 1
+  - clock-output-names: The names of the clocks. Supported clocks are "main",
+    "pll0", "pll1", "pll3", "lb", "qspi", "sdh", "sd0", "sd1" and "z"
+
+
+Example
+-------
+
+	cpg_clocks: cpg_clocks@e6150000 {
+		compatible = "renesas,r8a7790-cpg-clocks",
+			     "renesas,rcar-gen2-cpg-clocks";
+		reg = <0 0xe6150000 0 0x1000>;
+		clocks = <&extal_clk>;
+		#clock-cells = <1>;
+		clock-output-names = "main", "pll0, "pll1", "pll3",
+				     "lb", "qspi", "sdh", "sd0", "sd1", "z";
+	};