1 files changed, 28 insertions, 8 deletions

diff --git a/drivers/video/console/vgacon.c b/drivers/video/console/vgacon.c
index 167de397e4b4..12d9329d1408 100644
--- a/drivers/video/console/vgacon.c
+++ b/drivers/video/console/vgacon.c
@@ -56,6 +56,8 @@
 static DEFINE_SPINLOCK(vga_lock);
 static int cursor_size_lastfrom;
 static int cursor_size_lastto;
+static u32 vgacon_xres;
+static u32 vgacon_yres;
 static struct vgastate state;
 
 #define BLANK 0x0020
@@ -69,7 +71,7 @@ static struct vgastate state;
  * appear.
  */
 #undef TRIDENT_GLITCH
-
+#define VGA_FONTWIDTH       8   /* VGA does not support fontwidths != 8 */
 /*
  *  Interface used by the world
  */
@@ -325,6 +327,10 @@ static const char __init *vgacon_startup(void)
                 vga_scan_lines =
                     vga_video_font_height * vga_video_num_lines;
         }
+
+        vgacon_xres = ORIG_VIDEO_COLS * VGA_FONTWIDTH;
+        vgacon_yres = vga_scan_lines;
+
         return display_desc;
 }
 
@@ -503,10 +509,18 @@ 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;
+
+        vgacon_xres = width * VGA_FONTWIDTH;
+        vgacon_yres = height * c->vc_font.height;
         outb_p(VGA_CRTC_MODE, vga_video_port_reg);
         mode = inb_p(vga_video_port_val);
 
@@ -551,6 +565,10 @@ static int vgacon_doresize(struct vc_data *c,
 
 static int vgacon_switch(struct vc_data *c)
 {
+        int x = c->vc_cols * VGA_FONTWIDTH;
+        int y = c->vc_rows * c->vc_font.height;
+        int rows = ORIG_VIDEO_LINES * vga_default_font_height/
+                c->vc_font.height;
         /*
          * We need to save screen size here as it's the only way
          * we can spot the screen has been resized and we need to
@@ -566,10 +584,11 @@ static int vgacon_switch(struct vc_data *c)
                 scr_memcpyw((u16 *) c->vc_origin, (u16 *) c->vc_screenbuf,
                             c->vc_screenbuf_size > vga_vram_size ?
                                 vga_vram_size : c->vc_screenbuf_size);
-                if (!(vga_video_num_columns % 2) &&
-                    vga_video_num_columns <= ORIG_VIDEO_COLS &&
-                    vga_video_num_lines <= (ORIG_VIDEO_LINES *
-                        vga_default_font_height) / c->vc_font.height)
+
+                if ((vgacon_xres != x || vgacon_yres != y) &&
+                    (!(vga_video_num_columns % 2) &&
+                     vga_video_num_columns <= ORIG_VIDEO_COLS &&
+                     vga_video_num_lines <= rows))
                         vgacon_doresize(c, c->vc_cols, c->vc_rows);
         }
 
@@ -993,7 +1012,8 @@ static int vgacon_font_set(struct vc_data *c, struct console_font *font, unsigne
         if (vga_video_type < VIDEO_TYPE_EGAM)
                 return -EINVAL;
 
-        if (font->width != 8 || (charcount != 256 && charcount != 512))
+        if (font->width != VGA_FONTWIDTH ||
+            (charcount != 256 && charcount != 512))
                 return -EINVAL;
 
         rc = vgacon_do_font_op(&state, font->data, 1, charcount == 512);
@@ -1010,7 +1030,7 @@ static int vgacon_font_get(struct vc_data *c, struct console_font *font)
         if (vga_video_type < VIDEO_TYPE_EGAM)
                 return -EINVAL;
 
-        font->width = 8;
+        font->width = VGA_FONTWIDTH;
         font->height = c->vc_font.height;
         font->charcount = vga_512_chars ? 512 : 256;
         if (!font->data)