From 954de9141e75cf2f1ce69ccdbedc83ec827a01ec Mon Sep 17 00:00:00 2001
From: Samuel Thibault <samuel.thibault@ens-lyon.org>
Date: Sun, 8 Jan 2006 01:02:34 -0800
Subject: [PATCH] [PATCH] vgacon: fix doublescan mode
When doublescan mode is in use, scanlines must be doubled.
Thanks to Jason Dravet <dravet@hotmail.com> for reporting and testing.
Signed-off-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
---
drivers/video/console/vgacon.c | 8 +++++++-
1 file changed, 7 insertions(+), 1 deletion(-)
diff --git a/drivers/video/console/vgacon.c b/drivers/video/console/vgacon.c
index 167de397e4b43..f4e1c4b4191e7 100644
--- a/drivers/video/console/vgacon.c
+++ b/drivers/video/console/vgacon.c
@@ -503,10 +503,16 @@ static int vgacon_doresize(struct vc_data *c,
{
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);
--
2.30.2