[PATCH 1/2] Documentation: phy: introduce new optional property to specify drive impedance
robh at kernel.org
Mon Jan 9 10:06:27 PST 2017
On Thu, Jan 05, 2017 at 05:31:21PM +0800, Shawn Lin wrote:
> We need to modify the drive impedance according to the
> different hardware condition. So let's expose this to
> the DT.
> Signed-off-by: Shawn Lin <shawn.lin at rock-chips.com>
> Documentation/devicetree/bindings/phy/rockchip-emmc-phy.txt | 5 +++++
> 1 file changed, 5 insertions(+)
> diff --git a/Documentation/devicetree/bindings/phy/rockchip-emmc-phy.txt b/Documentation/devicetree/bindings/phy/rockchip-emmc-phy.txt
> index e3ea557..731aeb9 100644
> --- a/Documentation/devicetree/bindings/phy/rockchip-emmc-phy.txt
> +++ b/Documentation/devicetree/bindings/phy/rockchip-emmc-phy.txt
> @@ -14,6 +14,11 @@ specified by name:
> access to it), it is strongly suggested.
> - clocks: Should have a phandle to the card clock exported by the SDHCI driver.
> +Optional Properties:
> +- drive_impedance: Must be one of 33, 40, 50, 66, 100. This property allows
> + different boards to specify their own drive impedance depending on the
> + hardware condition.
Needs a vendor prefix. Don't use '_'. And needs unit suffix (-ohms).
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