[PATCH] fbcon: Add ability to save/restore graphics state

Add hooks to save and restore the graphics state.  These hooks are called in
fbcon_blank() when entering/leaving KD_GRAPHICS mode.  This is needed by
savagefb at least so it can cooperate with savage_dri and by cyblafb.

State save/restoration can be full or partial.
Signed-off-by: NAntonino Daplas <adaplas@pol.net>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

drivers/video/console/fbcon.c

@@ -2191,11 +2191,14 @@ static int fbcon_blank(struct vc_data *vc, int blank, int mode_switch)
 		ops->graphics = 1;
 
 		if (!blank) {
+			if (info->fbops->fb_save_state)
+				info->fbops->fb_save_state(info);
 			var.activate = FB_ACTIVATE_NOW | FB_ACTIVATE_FORCE;
 			fb_set_var(info, &var);
 			ops->graphics = 0;
 			ops->var = info->var;
-		}
+		} else if (info->fbops->fb_restore_state)
+			info->fbops->fb_restore_state(info);
 	}
 
  	if (!fbcon_is_inactive(vc, info)) {

include/linux/fb.h

@@ -617,6 +617,12 @@ struct fb_ops {
 
 	/* perform fb specific mmap */
 	int (*fb_mmap)(struct fb_info *info, struct file *file, struct vm_area_struct *vma);
+
+	/* save current hardware state */
+	void (*fb_save_state)(struct fb_info *info);
+
+	/* restore saved state */
+	void (*fb_restore_state)(struct fb_info *info);
 };
 
 #ifdef CONFIG_FB_TILEBLITTING