From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sven Luther Subject: Re: [Linux-fbdev-devel] [PATCH] FBDev: vga16fb port Date: Thu, 5 Dec 2002 19:03:14 +0100 Sender: linux-kernel-owner@vger.kernel.org Message-ID: <20021205180314.GA860@iliana> References: <1039050178.1075.82.camel@localhost.localdomain> Mime-Version: 1.0 Return-path: Content-Disposition: inline In-Reply-To: List-Id: Cc: Antonino Daplas , Sven Luther , Linux Fbdev development list , Linux Kernel Mailing List On Thu, Dec 05, 2002 at 05:35:56PM +0000, James Simmons wrote: > > > If X is running in native mode then it has to save the register state. > > Otherwise you cannot switch to a console. If X is running on top of > > fbdev, then state restore/saves are done using fb_set_var and > > fb_get_var. The registers are not touched, that's the purpose of fbdev. > > > > If you are running vgacon, fbdev, and native X, then yes, fbdev and X > > has to do a save of their initial state. > > Not really. When X closes /dev/fb then fb_release is called which if the That supposes X is fbdev aware (either using the fbdev driver or the UseFBDev option), right ? What if X knows nothing about fbdev, it will try restoring stuff as if it was in text mode. > driver supports it will switch back to text mode. The exception is > firmware based fbdev drivers like vesafb and offb. > > > > Does this also apply to vesafb ? > > Not too sure about this. vesa requires real-mode initialization. Either > > you do this at boot time, or fake a real-mode environment like what X > > does. > > X has to reset the vidoe hardware back to the state that matches what the > VESA mode was. Other wise it will mess you your system. > > P.S > > X on VESA fb always foobars my system when I exit X. With which driver ? (i am happily running the vesa X driver on top of vesafb without problems). Friendly, Sven Luther