From 2c1a4b0cbeb47c0376aa53df2b2a3a79670ca6aa Mon Sep 17 00:00:00 2001 From: Christoph Muellner Date: Fri, 22 Mar 2019 12:34:51 +0100 Subject: dt-bindings: phy: Add a new property drive-impedance-ohm for RK's emmc PHY This patch documents the new proprty drive-impedance-ohm for Rockchip's eMMC PHY node. Signed-off-by: Christoph Muellner Signed-off-by: Philipp Tomsich Signed-off-by: Kishon Vijay Abraham I --- Documentation/devicetree/bindings/phy/rockchip-emmc-phy.txt | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) (limited to 'Documentation/devicetree/bindings/phy') diff --git a/Documentation/devicetree/bindings/phy/rockchip-emmc-phy.txt b/Documentation/devicetree/bindings/phy/rockchip-emmc-phy.txt index e3ea55763b0a..e728786f21e0 100644 --- a/Documentation/devicetree/bindings/phy/rockchip-emmc-phy.txt +++ b/Documentation/devicetree/bindings/phy/rockchip-emmc-phy.txt @@ -7,12 +7,15 @@ Required properties: - reg: PHY register address offset and length in "general register files" -Optional clocks using the clock bindings (see ../clock/clock-bindings.txt), -specified by name: +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. Example: @@ -29,6 +32,7 @@ grf: syscon@ff770000 { reg = <0xf780 0x20>; clocks = <&sdhci>; clock-names = "emmcclk"; + drive-impedance-ohm = <50>; #phy-cells = <0>; }; }; -- cgit v1.2.3