xref: /linux/Documentation/devicetree/bindings/clock/renesas,rcar-usb2-clock-sel.yaml (revision 1ac731c529cd4d6adbce134754b51ff7d822b145) 
1# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
2%YAML 1.2
3---
4$id: http://devicetree.org/schemas/clock/renesas,rcar-usb2-clock-sel.yaml#
5$schema: http://devicetree.org/meta-schemas/core.yaml#
6
7title: Renesas R-Car USB 2.0 clock selector
8
9maintainers:
10  - Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
11
12description: |
13  If you connect an external clock to the USB_EXTAL pin only, you should set
14  the clock rate to "usb_extal" node only.
15  If you connect an oscillator to both the USB_XTAL and USB_EXTAL, this module
16  is not needed because this is default setting. (Of course, you can set the
17  clock rates to both "usb_extal" and "usb_xtal" nodes.
18
19  Case 1: An external clock connects to R-Car SoC
20    +----------+   +--- R-Car ---------------------+
21    |External  |---|USB_EXTAL ---> all usb channels|
22    |clock     |   |USB_XTAL                       |
23    +----------+   +-------------------------------+
24
25  In this case, we need this driver with "usb_extal" clock.
26
27  Case 2: An oscillator connects to R-Car SoC
28    +----------+   +--- R-Car ---------------------+
29    |Oscillator|---|USB_EXTAL -+-> all usb channels|
30    |          |---|USB_XTAL --+                   |
31    +----------+   +-------------------------------+
32  In this case, we don't need this selector.
33
34properties:
35  compatible:
36    items:
37      - enum:
38          - renesas,r8a774a1-rcar-usb2-clock-sel # RZ/G2M
39          - renesas,r8a774b1-rcar-usb2-clock-sel # RZ/G2N
40          - renesas,r8a774e1-rcar-usb2-clock-sel # RZ/G2H
41          - renesas,r8a7795-rcar-usb2-clock-sel  # R-Car H3
42          - renesas,r8a7796-rcar-usb2-clock-sel  # R-Car M3-W
43          - renesas,r8a77961-rcar-usb2-clock-sel # R-Car M3-W+
44      - const: renesas,rcar-gen3-usb2-clock-sel
45
46  reg:
47    maxItems: 1
48
49  clocks:
50    maxItems: 4
51
52  clock-names:
53    items:
54      - const: ehci_ohci
55      - const: hs-usb-if
56      - const: usb_extal
57      - const: usb_xtal
58
59  '#clock-cells':
60    const: 0
61
62  power-domains:
63    maxItems: 1
64
65  resets:
66    maxItems: 2
67
68  reset-names:
69    items:
70      - const: ehci_ohci
71      - const: hs-usb-if
72
73required:
74  - compatible
75  - reg
76  - clocks
77  - clock-names
78  - '#clock-cells'
79  - power-domains
80  - resets
81  - reset-names
82
83additionalProperties: false
84
85examples:
86  - |
87    #include <dt-bindings/clock/r8a7795-cpg-mssr.h>
88    #include <dt-bindings/power/r8a7795-sysc.h>
89
90    usb2_clksel: clock-controller@e6590630 {
91        compatible = "renesas,r8a7795-rcar-usb2-clock-sel",
92                     "renesas,rcar-gen3-usb2-clock-sel";
93        reg = <0xe6590630 0x02>;
94        clocks = <&cpg CPG_MOD 703>, <&cpg CPG_MOD 704>,
95                 <&usb_extal>, <&usb_xtal>;
96        clock-names = "ehci_ohci", "hs-usb-if", "usb_extal", "usb_xtal";
97        #clock-cells = <0>;
98        power-domains = <&sysc R8A7795_PD_ALWAYS_ON>;
99        resets = <&cpg 703>, <&cpg 704>;
100        reset-names = "ehci_ohci", "hs-usb-if";
101    };
102