From 8e252c3e4500eb8708de1d6e9ebead55a78a5d5d Mon Sep 17 00:00:00 2001 From: Krishna Kurapati Date: Tue, 31 Dec 2024 13:41:04 +0530 Subject: [PATCH] arm64: dts: qcom: sm6350: Disable USB U1/U2 entry Disable U1 and U2 power-saving states to improve stability of USB. These low-power link states, designed to reduce power consumption during idle periods, can cause issues in latency-sensitive or high throughput use cases. Over the years, some of the issues seen are as follows: 1. In device mode of operation, when UVC is active, enabling U1/U2 is sometimes causing packets drops due to delay in entry/exit of intermittent these low power states. These packet drops are often reflected as missed isochronous transfers, as the controller wasn't able to send packet in that microframe interval and hence glitches are seen on the final transmitted video output. 2. On older targets like SM8150/SM8250/SM8350, there have been throughput issues seen during tethering use cases. Disabling these intermittent power states enhances device stability without affecting power usage. Signed-off-by: Krishna Kurapati Signed-off-by: Prashanth K Reviewed-by: Konrad Dybcio Link: https://lore.kernel.org/r/20241231081115.3149850-7-quic_prashk@quicinc.com Signed-off-by: Bjorn Andersson --- arch/arm64/boot/dts/qcom/sm6350.dtsi | 2 ++ 1 file changed, 2 insertions(+) diff --git a/arch/arm64/boot/dts/qcom/sm6350.dtsi b/arch/arm64/boot/dts/qcom/sm6350.dtsi index 7b5c340df5f6..506e9ebea0e9 100644 --- a/arch/arm64/boot/dts/qcom/sm6350.dtsi +++ b/arch/arm64/boot/dts/qcom/sm6350.dtsi @@ -1924,6 +1924,8 @@ snps,has-lpm-erratum; snps,hird-threshold = /bits/ 8 <0x10>; snps,parkmode-disable-ss-quirk; + snps,dis-u1-entry-quirk; + snps,dis-u2-entry-quirk; phys = <&usb_1_hsphy>, <&usb_1_qmpphy QMP_USB43DP_USB3_PHY>; phy-names = "usb2-phy", "usb3-phy"; usb-role-switch; -- 2.50.1