---
name: "usb_root_hub_lost_power"
section: "9"
platform: "linux"
package: "linux-manual-4.9"
version: "4.9.228-1"
release: "Debian 9 (Stretch)"
platforms: ["linux"]
url: "https://new.carta.tech/usb_root_hub_lost_power"
---

# usb\_root\_hub\_lost\_power(9)

called by HCD if the root hub lost Vbus power

## NAME

usb\_root\_hub\_lost\_power - called by HCD if the root hub lost Vbus power

## SYNOPSIS

**void usb\_root\_hub\_lost\_power(struct usb\_device \*** *rhdev***);**

## ARGUMENTS

*rhdev*

struct usb\_device for the root hub

## DESCRIPTION

The USB host controller driver calls this function when its root hub is resumed and Vbus power has been interrupted or the controller has been reset. The routine marks *rhdev* as having lost power. When the hub driver is resumed it will take notice and carry out power-session recovery for all the “USB-PERSIST”-enabled child devices; the others will be disconnected.

## COPYRIGHT