From fe4ef45b5b40c496aa0c85d059c713c79b804e06 Mon Sep 17 00:00:00 2001 From: Paul Burton Date: Sun, 24 May 2015 16:11:34 +0100 Subject: DEVICETREE: Add Ingenic CGU binding documentation Document the devicetree binding for Ingenic SoC CGUs, and add headers defining the clock specifiers for clocks provided by the JZ4740 & JZ4780 CGU blocks. Signed-off-by: Paul Burton Cc: Ian Campbell Cc: Kumar Gala Cc: Lars-Peter Clausen Cc: Mark Rutland Cc: Mike Turquette Cc: Pawel Moll Cc: Rob Herring Cc: devicetree@vger.kernel.org Cc: linux-mips@linux-mips.org Cc: devicetree@vger.kernel.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/10152/ Signed-off-by: Ralf Baechle --- .../devicetree/bindings/clock/ingenic,cgu.txt | 53 ++++++++++++++++++++++ 1 file changed, 53 insertions(+) create mode 100644 Documentation/devicetree/bindings/clock/ingenic,cgu.txt (limited to 'Documentation') diff --git a/Documentation/devicetree/bindings/clock/ingenic,cgu.txt b/Documentation/devicetree/bindings/clock/ingenic,cgu.txt new file mode 100644 index 000000000000..f8d4134ae409 --- /dev/null +++ b/Documentation/devicetree/bindings/clock/ingenic,cgu.txt @@ -0,0 +1,53 @@ +Ingenic SoC CGU binding + +The CGU in an Ingenic SoC provides all the clocks generated on-chip. It +typically includes a variety of PLLs, multiplexers, dividers & gates in order +to provide many different clock signals derived from only 2 external source +clocks. + +Required properties: +- compatible : Should be "ingenic,-cgu". + For example "ingenic,jz4740-cgu" or "ingenic,jz4780-cgu". +- reg : The address & length of the CGU registers. +- clocks : List of phandle & clock specifiers for clocks external to the CGU. + Two such external clocks should be specified - first the external crystal + "ext" and second the RTC clock source "rtc". +- clock-names : List of name strings for the external clocks. +- #clock-cells: Should be 1. + Clock consumers specify this argument to identify a clock. The valid values + may be found in -cgu.h>. + +Example SoC include file: + +/ { + cgu: jz4740-cgu { + compatible = "ingenic,jz4740-cgu"; + reg = <0x10000000 0x100>; + #clock-cells = <1>; + }; + + uart0: serial@10030000 { + clocks = <&cgu JZ4740_CLK_UART0>; + }; +}; + +Example board file: + +/ { + ext: clock@0 { + compatible = "fixed-clock"; + #clock-cells = <0>; + clock-frequency = <12000000>; + }; + + rtc: clock@1 { + compatible = "fixed-clock"; + #clock-cells = <0>; + clock-frequency = <32768>; + }; + + &cgu { + clocks = <&ext> <&rtc>; + clock-names: "ext", "rtc"; + }; +}; -- cgit v1.2.3