USB ports are turned on by the firmware as it looks for disks to boot,
ensure that they aren't power cycled before the xHCI driver comes up.

This enables USB devices to be ready for use faster and reduces wear
and risk of data loss on storage devices. A particularly annoying case
was booting from a mechanical disk, which takes time to spin up again.

Vendor kernel also kept these ports powered, and by the same means.

Signed-off-by: Michal Pecio <michal.pecio@gmail.com>
---
 arch/arm/boot/dts/nvidia/tegra124-nyan.dtsi | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/arch/arm/boot/dts/nvidia/tegra124-nyan.dtsi b/arch/arm/boot/dts/nvidia/tegra124-nyan.dtsi
index 8125c1b..974c76f 100644
--- a/arch/arm/boot/dts/nvidia/tegra124-nyan.dtsi
+++ b/arch/arm/boot/dts/nvidia/tegra124-nyan.dtsi
@@ -716,6 +716,7 @@
 		regulator-name = "+5V_USB_HS";
 		regulator-min-microvolt = <5000000>;
 		regulator-max-microvolt = <5000000>;
+		regulator-boot-on;
 		gpio = <&gpio TEGRA_GPIO(N, 4) GPIO_ACTIVE_HIGH>;
 		enable-active-high;
 		gpio-open-drain;
@@ -727,6 +728,7 @@
 		regulator-name = "+5V_USB_SS";
 		regulator-min-microvolt = <5000000>;
 		regulator-max-microvolt = <5000000>;
+		regulator-boot-on;
 		gpio = <&gpio TEGRA_GPIO(N, 5) GPIO_ACTIVE_HIGH>;
 		enable-active-high;
 		gpio-open-drain;
-- 
1.9.1

From: Thierry Reding <treding@nvidia.com>


On Wed, 04 Dec 2024 21:44:43 +0100, Michal Pecio wrote:
> USB ports are turned on by the firmware as it looks for disks to boot,
> ensure that they aren't power cycled before the xHCI driver comes up.
> 
> This enables USB devices to be ready for use faster and reduces wear
> and risk of data loss on storage devices. A particularly annoying case
> was booting from a mechanical disk, which takes time to spin up again.
> 
> [...]

Applied, thanks!

[1/1] ARM: tegra: nyan: Maintain power to USB ports on boot
      commit: cec785a7f25d9ebe3a151ddc4f3a4ede7fc0dab0

Best regards,
-- 
Thierry Reding <treding@nvidia.com>