1 files changed, 23 insertions, 9 deletions

diff --git a/drivers/video/neofb.c b/drivers/video/neofb.c
index 24b12f71d5a8..2f156b724d1c 100644
--- a/drivers/video/neofb.c
+++ b/drivers/video/neofb.c
@@ -1333,17 +1333,22 @@ static int neofb_blank(int blank_mode, struct fb_info *info)
          *  run "setterm -powersave powerdown" to take advantage
          */
         struct neofb_par *par = info->par;
-        int seqflags, lcdflags, dpmsflags, reg;
-
+        int seqflags, lcdflags, dpmsflags, reg, tmpdisp;
 
         /*
-         * Reload the value stored in the register, if sensible. It might have
-         * been changed via FN keystroke.
+         * Read back the register bits related to display configuration. They might
+         * have been changed underneath the driver via Fn key stroke.
+         */
+        neoUnlock();
+        tmpdisp = vga_rgfx(NULL, 0x20) & 0x03;
+        neoLock(&par->state);
+
+        /* In case we blank the screen, we want to store the possibly new
+         * configuration in the driver. During un-blank, we re-apply this setting,
+         * since the LCD bit will be cleared in order to switch off the backlight.
          */
         if (par->PanelDispCntlRegRead) {
-                neoUnlock();
-                par->PanelDispCntlReg1 = vga_rgfx(NULL, 0x20) & 0x03;
-                neoLock(&par->state);
+                par->PanelDispCntlReg1 = tmpdisp;
         }
         par->PanelDispCntlRegRead = !blank_mode;
 
@@ -1378,12 +1383,21 @@ static int neofb_blank(int blank_mode, struct fb_info *info)
                 break;
         case FB_BLANK_NORMAL:           /* just blank screen (backlight stays on) */
                 seqflags = VGA_SR01_SCREEN_OFF; /* Disable sequencer */
-                lcdflags = par->PanelDispCntlReg1 & 0x02; /* LCD normal */
+                /*
+                 * During a blank operation with the LID shut, we might store "LCD off"
+                 * by mistake. Due to timing issues, the BIOS may switch the lights
+                 * back on, and we turn it back off once we "unblank".
+                 *
+                 * So here is an attempt to implement ">=" - if we are in the process
+                 * of unblanking, and the LCD bit is unset in the driver but set in the
+                 * register, we must keep it.
+                 */
+                lcdflags = ((par->PanelDispCntlReg1 | tmpdisp) & 0x02); /* LCD normal */
                 dpmsflags = 0x00;       /* no hsync/vsync suppression */
                 break;
         case FB_BLANK_UNBLANK:          /* unblank */
                 seqflags = 0;                   /* Enable sequencer */
-                lcdflags = par->PanelDispCntlReg1 & 0x02; /* LCD normal */
+                lcdflags = ((par->PanelDispCntlReg1 | tmpdisp) & 0x02); /* LCD normal */
                 dpmsflags = 0x00;       /* no hsync/vsync suppression */
 #ifdef CONFIG_TOSHIBA
                 /* Do we still need this ? */