Subject: Re: how to turn off display? (wsdisplay0 at vesafb0)
To: Jeremy C. Reed <>
From: Jared D. McNeill <>
List: tech-kern
Date: 08/01/2006 00:33:08
On Mon, 31 Jul 2006, Jeremy C. Reed wrote:
> Can someone point me to a tool or code for turning off a display or
> powering down a laptop screen?
> I am using NetBSD/i386 3.99.21 with:
>  wsdisplay0 at vesafb0 kbdmux 1: console (fb, vt100 emulation)
> And Xorg's wsfb(4) driver.

``options VESAFB_PM'' in your kernel will enable the WSDISPLAYIO_SVIDEO 
and WSDISPLAYIO_GVIDEO ioctl implementations, which wsfb(4) should use 
when it decides to blank the display.

It currently defaults to 'standby' mode; you will need to modify vesafb.c 
(see vesafb_svideo) if you want to attempt another mode that your video 
BIOS supports -- possible values are 'standby', 'suspend', 'off', and 

YMMV, as I've seen certain systems simply reset when I attempt to call the 
video PM BIOS function.