linux/Documentation/devicetree/bindings/clock/nvidia,tegra20-car.txt

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NVIDIA Tegra20 Clock And Reset Controller
This binding uses the common clock binding:
Documentation/devicetree/bindings/clock/clock-bindings.txt
The CAR (Clock And Reset) Controller on Tegra is the HW module responsible
for muxing and gating Tegra's clocks, and setting their rates.
Required properties :
- compatible : Should be "nvidia,tegra20-car"
- reg : Should contain CAR registers location and length
- clocks : Should contain phandle and clock specifiers for two clocks:
the 32 KHz "32k_in", and the board-specific oscillator "osc".
- #clock-cells : Should be 1.
In clock consumers, this cell represents the clock ID exposed by the
CAR. The assignments may be found in header file
<dt-bindings/clock/tegra20-car.h>.
- #reset-cells : Should be 1.
In clock consumers, this cell represents the bit number in the CAR's
array of CLK_RST_CONTROLLER_RST_DEVICES_* registers.
Example SoC include file:
/ {
tegra_car: clock {
compatible = "nvidia,tegra20-car";
reg = <0x60006000 0x1000>;
#clock-cells = <1>;
#reset-cells = <1>;
};
usb@c5004000 {
clocks = <&tegra_car TEGRA20_CLK_USB2>;
};
};
Example board file:
/ {
clocks {
compatible = "simple-bus";
#address-cells = <1>;
#size-cells = <0>;
osc: clock@0 {
compatible = "fixed-clock";
reg = <0>;
#clock-cells = <0>;
clock-frequency = <12000000>;
};
clk_32k: clock@1 {
compatible = "fixed-clock";
reg = <1>;
#clock-cells = <0>;
clock-frequency = <32768>;
};
};
&tegra_car {
clocks = <&clk_32k> <&osc>;
};
};