Documentation/devicetree/bindings/clock/renesas,rcar-usb2-clock-sel.yaml

   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
   7 title: Renesas R-Car USB 2.0 clock selector
   8
   9 maintainers:
  10   - Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
  11
  12 description: |
  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
  34 properties:
  35   compatible:
  36     items:
  37       - enum:
  38           - renesas,r8a7795-rcar-usb2-clock-sel  # R-Car H3
  39           - renesas,r8a7796-rcar-usb2-clock-sel  # R-Car M3-W
  40           - renesas,r8a77961-rcar-usb2-clock-sel # R-Car M3-W+
  41       - const: renesas,rcar-gen3-usb2-clock-sel
  42
  43   reg:
  44     maxItems: 1
  45
  46   clocks:
  47     minItems: 4
  48     maxItems: 4
  49
  50   clock-names:
  51     items:
  52       - const: ehci_ohci
  53       - const: hs-usb-if
  54       - const: usb_extal
  55       - const: usb_xtal
  56
  57   '#clock-cells':
  58     const: 0
  59
  60   power-domains:
  61     maxItems: 1
  62
  63   resets:
  64     minItems: 2
  65     maxItems: 2
  66
  67   reset-names:
  68     items:
  69       - const: ehci_ohci
  70       - const: hs-usb-if
  71
  72 required:
  73   - compatible
  74   - reg
  75   - clocks
  76   - clock-names
  77   - '#clock-cells'
  78   - power-domains
  79   - resets
  80   - reset-names
  81
  82 additionalProperties: false
  83
  84 examples:
  85   - |
  86     #include <dt-bindings/clock/r8a7795-cpg-mssr.h>
  87     #include <dt-bindings/power/r8a7795-sysc.h>
  88
  89     usb2_clksel: clock-controller@e6590630 {
  90         compatible = "renesas,r8a7795-rcar-usb2-clock-sel",
  91                      "renesas,rcar-gen3-usb2-clock-sel";
  92         reg = <0xe6590630 0x02>;
  93         clocks = <&cpg CPG_MOD 703>, <&cpg CPG_MOD 704>,
  94                  <&usb_extal>, <&usb_xtal>;
  95         clock-names = "ehci_ohci", "hs-usb-if", "usb_extal", "usb_xtal";
  96         #clock-cells = <0>;
  97         power-domains = <&sysc R8A7795_PD_ALWAYS_ON>;
  98         resets = <&cpg 703>, <&cpg 704>;
  99         reset-names = "ehci_ohci", "hs-usb-if";
 100     };