1Binding for TI mux clock. 2 3Binding status: Unstable - ABI compatibility may be broken in the future 4 5This binding uses the common clock binding[1]. It assumes a 6register-mapped multiplexer with multiple input clock signals or 7parents, one of which can be selected as output. This clock does not 8gate or adjust the parent rate via a divider or multiplier. 9 10By default the "clocks" property lists the parents in the same order 11as they are programmed into the register. E.g: 12 13 clocks = <&foo_clock>, <&bar_clock>, <&baz_clock>; 14 15results in programming the register as follows: 16 17register value selected parent clock 180 foo_clock 191 bar_clock 202 baz_clock 21 22Some clock controller IPs do not allow a value of zero to be programmed 23into the register, instead indexing begins at 1. The optional property 24"index-starts-at-one" modified the scheme as follows: 25 26register value selected clock parent 271 foo_clock 282 bar_clock 293 baz_clock 30 31The binding must provide the register to control the mux. Optionally 32the number of bits to shift the control field in the register can be 33supplied. If the shift value is missing it is the same as supplying 34a zero shift. 35 36[1] Documentation/devicetree/bindings/clock/clock-bindings.txt 37 38Required properties: 39- compatible : shall be "ti,mux-clock" or "ti,composite-mux-clock". 40- #clock-cells : from common clock binding; shall be set to 0. 41- clocks : link phandles of parent clocks 42- reg : register offset for register controlling adjustable mux 43 44Optional properties: 45- clock-output-names : from common clock binding. 46- ti,bit-shift : number of bits to shift the bit-mask, defaults to 47 0 if not present 48- ti,index-starts-at-one : valid input select programming starts at 1, not 49 zero 50- ti,set-rate-parent : clk_set_rate is propagated to parent clock, 51 not supported by the composite-mux-clock subtype 52- ti,latch-bit : latch the mux value to HW, only needed if the register 53 access requires this. As an example, dra7x DPLL_GMAC H14 muxing 54 implements such behavior. 55 56Examples: 57 58sys_clkin_ck: sys_clkin_ck@4a306110 { 59 #clock-cells = <0>; 60 compatible = "ti,mux-clock"; 61 clocks = <&virt_12000000_ck>, <&virt_13000000_ck>, <&virt_16800000_ck>, <&virt_19200000_ck>, <&virt_26000000_ck>, <&virt_27000000_ck>, <&virt_38400000_ck>; 62 reg = <0x0110>; 63 ti,index-starts-at-one; 64}; 65 66abe_dpll_bypass_clk_mux_ck: abe_dpll_bypass_clk_mux_ck@4a306108 { 67 #clock-cells = <0>; 68 compatible = "ti,mux-clock"; 69 clocks = <&sys_clkin_ck>, <&sys_32k_ck>; 70 ti,bit-shift = <24>; 71 reg = <0x0108>; 72}; 73 74mcbsp5_mux_fck: mcbsp5_mux_fck { 75 #clock-cells = <0>; 76 compatible = "ti,composite-mux-clock"; 77 clocks = <&core_96m_fck>, <&mcbsp_clks>; 78 ti,bit-shift = <4>; 79 reg = <0x02d8>; 80}; 81