arm64: dts: rockchip: disable tx ipgap linecheck for rk3399 dwc3

RK3399 USB DWC3 controller has a issue that FS/LS devices not
recognized if inserted through USB 3.0 HUB. It's because that
the inter-packet delay between the SSPLIT token to SETUP token
is about 566ns, more then the USB spec requirement.

This patch adds a quirk "snps,dis-tx-ipgap-linecheck-quirk" to
disable the u2mac linestate check to decrease the SSPLIT token
to SETUP token inter-packet delay from 566ns to 466ns.

Signed-off-by: William Wu <william.wu@rock-chips.com>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>

diff --git a/arch/arm64/boot/dts/rockchip/rk3399.dtsi b/arch/arm64/boot/dts/rockchip/rk3399.dtsi
index 27a4616..69cb311 100644 (file)
--- a/arch/arm64/boot/dts/rockchip/rk3399.dtsi
+++ b/arch/arm64/boot/dts/rockchip/rk3399.dtsi
@@ -412,6 +412,7 @@
                        snps,dis-u2-freeclk-exists-quirk;
                        snps,dis_u2_susphy_quirk;
                        snps,dis-del-phy-power-chg-quirk;
+                       snps,dis-tx-ipgap-linecheck-quirk;
                        status = "disabled";
                };
        };
@@ -439,6 +440,7 @@
                        snps,dis-u2-freeclk-exists-quirk;
                        snps,dis_u2_susphy_quirk;
                        snps,dis-del-phy-power-chg-quirk;
+                       snps,dis-tx-ipgap-linecheck-quirk;
                        status = "disabled";
                };
        };