From 8977c947b321858ad878106e6c1dbfb719f23db6 Mon Sep 17 00:00:00 2001 From: Peter Chen Date: Tue, 21 Aug 2018 17:15:36 +0800 Subject: [PATCH] doc: dt-binding: ci-hdrc-usb2: add property for samsung picophy Add two parameters which are used to tune USB signal for samsung picophy, which is used at imx7d, imx8mm, and imx8mn. Reviewed-by: Rob Herring Reviewed-by: Jun Li Signed-off-by: Peter Chen --- Documentation/devicetree/bindings/usb/ci-hdrc-usb2.txt | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/Documentation/devicetree/bindings/usb/ci-hdrc-usb2.txt b/Documentation/devicetree/bindings/usb/ci-hdrc-usb2.txt index 51376cbe5f3d..a5c5db6a0b2d 100644 --- a/Documentation/devicetree/bindings/usb/ci-hdrc-usb2.txt +++ b/Documentation/devicetree/bindings/usb/ci-hdrc-usb2.txt @@ -100,6 +100,15 @@ i.mx specific properties It's recommended to specify the over current polarity. - power-active-high: power signal polarity is active high - external-vbus-divider: enables off-chip resistor divider for Vbus +- samsung,picophy-pre-emp-curr-control: HS Transmitter Pre-Emphasis Current + Control. This signal controls the amount of current sourced to the + USB_OTG*_DP and USB_OTG*_DN pins after a J-to-K or K-to-J transition. + The range is from 0x0 to 0x3, the default value is 0x1. + Details can refer to TXPREEMPAMPTUNE0 bits of USBNC_n_PHY_CFG1. +- samsung,picophy-dc-vol-level-adjust: HS DC Voltage Level Adjustment. + Adjust the high-speed transmitter DC level voltage. + The range is from 0x0 to 0xf, the default value is 0x3. + Details can refer to TXVREFTUNE0 bits of USBNC_n_PHY_CFG1. Example: