1* Renesas R-Car USB 2.0 clock selector
2
3This file provides information on what the device node for the R-Car USB 2.0
4clock selector.
5
6If you connect an external clock to the USB_EXTAL pin only, you should set
7the clock rate to "usb_extal" node only.
8If you connect an oscillator to both the USB_XTAL and USB_EXTAL, this module
9is not needed because this is default setting. (Of course, you can set the
10clock rates to both "usb_extal" and "usb_xtal" nodes.
11
12Case 1: An external clock connects to R-Car SoC
13	+----------+   +--- R-Car ---------------------+
14	|External  |---|USB_EXTAL ---> all usb channels|
15	|clock     |   |USB_XTAL                       |
16	+----------+   +-------------------------------+
17In this case, we need this driver with "usb_extal" clock.
18
19Case 2: An oscillator connects to R-Car SoC
20	+----------+   +--- R-Car ---------------------+
21	|Oscillator|---|USB_EXTAL -+-> all usb channels|
22	|          |---|USB_XTAL --+                   |
23	+----------+   +-------------------------------+
24In this case, we don't need this selector.
25
26Required properties:
27- compatible: "renesas,r8a7795-rcar-usb2-clock-sel" if the device is a part of
28	      an R8A7795 SoC.
29	      "renesas,r8a7796-rcar-usb2-clock-sel" if the device if a part of
30	      an R8A7796 SoC.
31	      "renesas,rcar-gen3-usb2-clock-sel" for a generic R-Car Gen3
32	      compatible device.
33
34	      When compatible with the generic version, nodes must list the
35	      SoC-specific version corresponding to the platform first
36	      followed by the generic version.
37
38- reg: offset and length of the USB 2.0 clock selector register block.
39- clocks: A list of phandles and specifier pairs.
40- clock-names: Name of the clocks.
41 - The functional clock must be "ehci_ohci"
42 - The USB_EXTAL clock pin must be "usb_extal"
43 - The USB_XTAL clock pin must be "usb_xtal"
44- #clock-cells: Must be 0
45
46Example (R-Car H3):
47
48	usb2_clksel: clock-controller@e6590630 {
49		compatible = "renesas,r8a77950-rcar-usb2-clock-sel",
50			     "renesas,rcar-gen3-usb2-clock-sel";
51		reg = <0 0xe6590630 0 0x02>;
52		clocks = <&cpg CPG_MOD 703>, <&usb_extal>, <&usb_xtal>;
53		clock-names = "ehci_ohci", "usb_extal", "usb_xtal";
54		#clock-cells = <0>;
55	};
56