[PATCH v5 2/4] dt-bindings: add bindings for rk3328 clock controller

From: Elaine Zhang
Date: Wed Dec 28 2016 - 21:45:28 EST


Add devicetree bindings for Rockchip cru which found on
Rockchip SoCs.

Changes in v4:
dropping the "rockchip,cru" and "syscon" properties for bindings of rk3328

Signed-off-by: Elaine Zhang <zhangqing@xxxxxxxxxxxxxx>
---
.../bindings/clock/rockchip,rk3328-cru.txt | 57 ++++++++++++++++++++++
1 file changed, 57 insertions(+)
create mode 100644 Documentation/devicetree/bindings/clock/rockchip,rk3328-cru.txt

diff --git a/Documentation/devicetree/bindings/clock/rockchip,rk3328-cru.txt b/Documentation/devicetree/bindings/clock/rockchip,rk3328-cru.txt
new file mode 100644
index 000000000000..e71c675ba5da
--- /dev/null
+++ b/Documentation/devicetree/bindings/clock/rockchip,rk3328-cru.txt
@@ -0,0 +1,57 @@
+* Rockchip RK3328 Clock and Reset Unit
+
+The RK3328 clock controller generates and supplies clock to various
+controllers within the SoC and also implements a reset controller for SoC
+peripherals.
+
+Required Properties:
+
+- compatible: should be "rockchip,rk3328-cru"
+- reg: physical base address of the controller and length of memory mapped
+ region.
+- #clock-cells: should be 1.
+- #reset-cells: should be 1.
+
+Optional Properties:
+
+- rockchip,grf: phandle to the syscon managing the "general register files"
+ If missing pll rates are not changeable, due to the missing pll lock status.
+
+Each clock is assigned an identifier and client nodes can use this identifier
+to specify the clock which they consume. All available clocks are defined as
+preprocessor macros in the dt-bindings/clock/rk3328-cru.h headers and can be
+used in device tree sources. Similar macros exist for the reset sources in
+these files.
+
+External clocks:
+
+There are several clocks that are generated outside the SoC. It is expected
+that they are defined using standard clock bindings with following
+clock-output-names:
+ - "xin24m" - crystal input - required,
+ - "clkin_i2s" - external I2S clock - optional,
+ - "gmac_clkin" - external GMAC clock - optional
+ - "phy_50m_out" - output clock of the pll in the mac phy
+
+Example: Clock controller node:
+
+ cru: clock-controller@ff440000 {
+ compatible = "rockchip,rk3328-cru";
+ reg = <0x0 0xff440000 0x0 0x1000>;
+ rockchip,grf = <&grf>;
+
+ #clock-cells = <1>;
+ #reset-cells = <1>;
+ };
+
+Example: UART controller node that consumes the clock generated by the clock
+ controller:
+
+ uart0: serial@ff120000 {
+ compatible = "snps,dw-apb-uart";
+ reg = <0xff120000 0x100>;
+ interrupts = <GIC_SPI 56 IRQ_TYPE_LEVEL_HIGH>;
+ reg-shift = <2>;
+ reg-io-width = <4>;
+ clocks = <&cru SCLK_UART0>;
+ };
--
1.9.1