Re: [PATCH] vgacon: Workaround for resize bug in some chipsets

["Jason Dravet" <dravet@hotmail.com>]

>From: Samuel Thibault <samuel.thibault@ens-lyon.org>
>To: Jason Dravet <dravet@hotmail.com>
>CC: 7eggert@gmx.de, adaplas@gmail.com, torvalds@osdl.org, 
>akpm@osdl.org,davej@redhat.com, linux-kernel@vger.kernel.org
>Subject: Re: [PATCH] vgacon: Workaround for resize bug in some chipsets
>Date: Thu, 17 Nov 2005 00:52:16 +0100
>
>Hi,
>
>The following patch should correct the issue:
>
>When doublescan mode is in use, scanlines must be doubled.
>
>Signed-off-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
>
>--- drivers/video/console/vgacon.c.orig	2005-11-17 00:40:02.000000000 +0100
>+++ drivers/video/console/vgacon.c	2005-11-17 00:42:27.000000000 +0100
>@@ -502,10 +502,16 @@
>  {
>  	unsigned long flags;
>  	unsigned int scanlines = height * c->vc_font.height;
>-	u8 scanlines_lo, r7, vsync_end, mode;
>+	u8 scanlines_lo, r7, vsync_end, mode, max_scan;
>
>  	spin_lock_irqsave(&vga_lock, flags);
>
>+	outb_p(VGA_CRTC_MAX_SCAN, vga_video_port_reg);
>+	max_scan = inb_p(vga_video_port_val);
>+
>+	if (max_scan & 0x80)
>+		scanlines <<= 1;
>+
>  	outb_p(VGA_CRTC_MODE, vga_video_port_reg);
>  	mode = inb_p(vga_video_port_val);
>

The patch does fix my problem.  Thank you Samuel.  I really appreciate the 
work you and Antonino have done on this issue.  I look forward to seeing 
this patch in the mainline.

Thanks again,
Jason Dravet