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Diffstat (limited to 'Documentation/devicetree/bindings/clock/lpc1850-creg-clk.txt')
-rw-r--r-- | Documentation/devicetree/bindings/clock/lpc1850-creg-clk.txt | 52 |
1 files changed, 52 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/clock/lpc1850-creg-clk.txt b/Documentation/devicetree/bindings/clock/lpc1850-creg-clk.txt new file mode 100644 index 000000000..6f1c7b4e4 --- /dev/null +++ b/Documentation/devicetree/bindings/clock/lpc1850-creg-clk.txt @@ -0,0 +1,52 @@ +* NXP LPC1850 CREG clocks + +The NXP LPC18xx/43xx CREG (Configuration Registers) block contains +control registers for two low speed clocks. One of the clocks is a +32 kHz oscillator driver with power up/down and clock gating. Next +is a fixed divider that creates a 1 kHz clock from the 32 kHz osc. + +These clocks are used by the RTC and the Event Router peripherials. +The 32 kHz can also be routed to other peripherials to enable low +power modes. + +This binding uses the common clock binding: + Documentation/devicetree/bindings/clock/clock-bindings.txt + +Required properties: +- compatible: + Should be "nxp,lpc1850-creg-clk" +- #clock-cells: + Shall have value <1>. +- clocks: + Shall contain a phandle to the fixed 32 kHz crystal. + +The creg-clk node must be a child of the creg syscon node. + +The following clocks are available from the clock node. + +Clock ID Name + 0 1 kHz clock + 1 32 kHz Oscillator + +Example: +soc { + creg: syscon@40043000 { + compatible = "nxp,lpc1850-creg", "syscon", "simple-mfd"; + reg = <0x40043000 0x1000>; + + creg_clk: clock-controller { + compatible = "nxp,lpc1850-creg-clk"; + clocks = <&xtal32>; + #clock-cells = <1>; + }; + + ... + }; + + rtc: rtc@40046000 { + ... + clocks = <&creg_clk 0>, <&ccu1 CLK_CPU_BUS>; + clock-names = "rtc", "reg"; + ... + }; +}; |