linux-stable/Documentation/devicetree/bindings/phy/rockchip-emmc-phy.txt
Chris Ruehl 88d9f40c4b devicetree: phy: rockchip-emmc optional add vendor prefix
Update the documentation and add the vendor prefix to the optional
properties referred in vendor-prefixes.yaml.
Follow up with
commit 8b5c2b45b8 ("phy: rockchip: set pulldown for strobe line in dts")
commit a8cef92827 ("phy: rockchip-emmc: output tap delay dt property")

Signed-off-by: Chris Ruehl <chris.ruehl@gtsys.com.hk>
Reviewed-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20201215014409.905-2-chris.ruehl@gtsys.com.hk
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2021-01-13 17:28:24 +05:30

43 lines
1.4 KiB
Text

Rockchip EMMC PHY
-----------------------
Required properties:
- compatible: rockchip,rk3399-emmc-phy
- #phy-cells: must be 0
- reg: PHY register address offset and length in "general
register files"
Optional properties:
- clock-names: Should contain "emmcclk". Although this is listed as optional
(because most boards can get basic functionality without having
access to it), it is strongly suggested.
See ../clock/clock-bindings.txt for details.
- clocks: Should have a phandle to the card clock exported by the SDHCI driver.
- drive-impedance-ohm: Specifies the drive impedance in Ohm.
Possible values are 33, 40, 50, 66 and 100.
If not set, the default value of 50 will be applied.
- rockchip,enable-strobe-pulldown: Enable internal pull-down for the strobe
line. If not set, pull-down is not used.
- rockchip,output-tapdelay-select: Specifies the phyctrl_otapdlysec register.
If not set, the register defaults to 0x4.
Maximum value 0xf.
Example:
grf: syscon@ff770000 {
compatible = "rockchip,rk3399-grf", "syscon", "simple-mfd";
#address-cells = <1>;
#size-cells = <1>;
...
emmcphy: phy@f780 {
compatible = "rockchip,rk3399-emmc-phy";
reg = <0xf780 0x20>;
clocks = <&sdhci>;
clock-names = "emmcclk";
drive-impedance-ohm = <50>;
#phy-cells = <0>;
};
};