linux/Documentation/devicetree/bindings/clock/idt,versaclock5.txt

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Binding for IDT VersaClock5 programmable i2c clock generator.
The IDT VersaClock5 are programmable i2c clock generators providing
from 3 to 12 output clocks.
==I2C device node==
Required properties:
- compatible: shall be one of "idt,5p49v5923" , "idt,5p49v5933" ,
"idt,5p49v5935".
- reg: i2c device address, shall be 0x68 or 0x6a.
- #clock-cells: from common clock binding; shall be set to 1.
- clocks: from common clock binding; list of parent clock handles,
- 5p49v5923: (required) either or both of XTAL or CLKIN
reference clock.
- 5p49v5933 and
- 5p49v5935: (optional) property not present (internal
Xtal used) or CLKIN reference
clock.
- clock-names: from common clock binding; clock input names, can be
- 5p49v5923: (required) either or both of "xin", "clkin".
- 5p49v5933 and
- 5p49v5935: (optional) property not present or "clkin".
==Mapping between clock specifier and physical pins==
When referencing the provided clock in the DT using phandle and
clock specifier, the following mapping applies:
5P49V5923:
0 -- OUT0_SEL_I2CB
1 -- OUT1
2 -- OUT2
5P49V5933:
0 -- OUT0_SEL_I2CB
1 -- OUT1
2 -- OUT4
5P49V5935:
0 -- OUT0_SEL_I2CB
1 -- OUT1
2 -- OUT2
3 -- OUT3
4 -- OUT4
==Example==
/* 25MHz reference crystal */
ref25: ref25m {
compatible = "fixed-clock";
#clock-cells = <0>;
clock-frequency = <25000000>;
};
i2c-master-node {
/* IDT 5P49V5923 i2c clock generator */
vc5: clock-generator@6a {
compatible = "idt,5p49v5923";
reg = <0x6a>;
#clock-cells = <1>;
/* Connect XIN input to 25MHz reference */
clocks = <&ref25m>;
clock-names = "xin";
};
};
/* Consumer referencing the 5P49V5923 pin OUT1 */
consumer {
...
clocks = <&vc5 1>;
...
}