From mboxrd@z Thu Jan 1 00:00:00 1970 From: Shawn Lin Subject: [PATCH 1/2] Documentation: phy: introduce new optional property to specify drive impedance Date: Thu, 5 Jan 2017 17:31:21 +0800 Message-ID: <1483608682-226716-1-git-send-email-shawn.lin@rock-chips.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "Linux-rockchip" Errors-To: linux-rockchip-bounces+glpar-linux-rockchip=m.gmane.org-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org To: Kishon Vijay Abraham I Cc: devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Heiko Stuebner , Shawn Lin , Douglas Anderson , linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-rockchip-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, Rob Herring List-Id: devicetree@vger.kernel.org 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 --- 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. + Example: -- 1.9.1