ubuntu-linux-kernel/Documentation/devicetree/bindings/phy/rcar-gen3-phy-usb3.txt

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2024-04-01 15:06:58 +00:00
* Renesas R-Car generation 3 USB 3.0 PHY
This file provides information on what the device node for the R-Car generation
3 USB 3.0 PHY contains.
If you want to enable spread spectrum clock (ssc), you should use USB_EXTAL
instead of USB3_CLK. However, if you don't want to these features, you don't
need this driver.
Required properties:
- compatible: "renesas,r8a7795-usb3-phy" if the device is a part of an R8A7795
SoC.
"renesas,r8a7796-usb3-phy" if the device is a part of an R8A7796
SoC.
"renesas,rcar-gen3-usb3-phy" for a generic R-Car Gen3 compatible
device.
When compatible with the generic version, nodes must list the
SoC-specific version corresponding to the platform first
followed by the generic version.
- reg: offset and length of the USB 3.0 PHY register block.
- clocks: A list of phandles and clock-specifier pairs.
- clock-names: Name of the clocks.
- The funcional clock must be "usb3-if".
- The usb3's external clock must be "usb3s_clk".
- The usb2's external clock must be "usb_extal". If you want to use the ssc,
the clock-frequency must not be 0.
- #phy-cells: see phy-bindings.txt in the same directory, must be <0>.
Optional properties:
- renesas,ssc-range: Enable/disable spread spectrum clock (ssc) by using
the following values as u32:
- 0 (or the property doesn't exist): disable the ssc
- 4980: enable the ssc as -4980 ppm
- 4492: enable the ssc as -4492 ppm
- 4003: enable the ssc as -4003 ppm
Example (R-Car H3):
usb-phy@e65ee000 {
compatible = "renesas,r8a7795-usb3-phy",
"renesas,rcar-gen3-usb3-phy";
reg = <0 0xe65ee000 0 0x90>;
clocks = <&cpg CPG_MOD 328>, <&usb3s0_clk>, <&usb_extal>;
clock-names = "usb3-if", "usb3s_clk", "usb_extal";
};