Binding for Silicon Labs Si5351a/b/c programmable i2c clock generator. Reference [1] Si5351A/B/C Data Sheet http://www.silabs.com/Support%20Documents/TechnicalDocs/Si5351.pdf The Si5351a/b/c are programmable i2c clock generators with up to 8 output clocks. Si5351a also has a reduced pin-count package (MSOP10) where only 3 output clocks are accessible. The internal structure of the clock generators can be found in [1]. ==I2C device node== Required properties: - compatible: shall be one of "silabs,si5351{a,a-msop,b,c}". - reg: i2c device address, shall be 0x60 or 0x61. - #clock-cells: from common clock binding; shall be set to 1. - clocks: from common clock binding; list of parent clock handles, shall be xtal reference clock or xtal and clkin for si5351c only. Corresponding clock input names are "xtal" and "clkin" respectively. - #address-cells: shall be set to 1. - #size-cells: shall be set to 0. Optional properties: - silabs,pll-source: pair of (number, source) for each pll. Allows to overwrite clock source of pll A (number=0) or B (number=1). ==Child nodes== Each of the clock outputs can be overwritten individually by using a child node to the I2C device node. If a child node for a clock output is not set, the eeprom configuration is not overwritten. Required child node properties: - reg: number of clock output. Optional child node properties: - silabs,clock-source: source clock of the output divider stage N, shall be 0 = multisynth N 1 = multisynth 0 for output clocks 0-3, else multisynth4 2 = xtal 3 = clkin (si5351c only) - silabs,drive-strength: output drive strength in mA, shall be one of {2,4,6,8}. - silabs,multisynth-source: source pll A(0) or B(1) of corresponding multisynth divider. - silabs,pll-master: boolean, multisynth can change pll frequency. - silabs,disable-state : clock output disable state, shall be 0 = clock output is driven LOW when disabled 1 = clock output is driven HIGH when disabled 2 = clock output is FLOATING (HIGH-Z) when disabled 3 = clock output is NEVER disabled ==Example== /* 25MHz reference crystal */ ref25: ref25M { compatible = "fixed-clock"; #clock-cells = <0>; clock-frequency = <25000000>; }; i2c-master-node { /* Si5351a msop10 i2c clock generator */ si5351a: clock-generator@60 { compatible = "silabs,si5351a-msop"; reg = <0x60>; #address-cells = <1>; #size-cells = <0>; #clock-cells = <1>; /* connect xtal input to 25MHz reference */ clocks = <&ref25>; clock-names = "xtal"; /* connect xtal input as source of pll0 and pll1 */ silabs,pll-source = <0 0>, <1 0>; /* * overwrite clkout0 configuration with: * - 8mA output drive strength * - pll0 as clock source of multisynth0 * - multisynth0 as clock source of output divider * - multisynth0 can change pll0 * - set initial clock frequency of 74.25MHz */ clkout0 { reg = <0>; silabs,drive-strength = <8>; silabs,multisynth-source = <0>; silabs,clock-source = <0>; silabs,pll-master; clock-frequency = <74250000>; }; /* * overwrite clkout1 configuration with: * - 4mA output drive strength * - pll1 as clock source of multisynth1 * - multisynth1 as clock source of output divider * - multisynth1 can change pll1 */ clkout1 { reg = <1>; silabs,drive-strength = <4>; silabs,multisynth-source = <1>; silabs,clock-source = <0>; pll-master; }; /* * overwrite clkout2 configuration with: * - xtal as clock source of output divider */ clkout2 { reg = <2>; silabs,clock-source = <2>; }; }; };