+static int get_lcd_state(void)
+{
+ return read_status(LCD_ON);
+}
+
+static int set_lcd_state(int value)
+{
+ int lcd = 0;
+ acpi_status status = 0;
+
+ lcd = value ? 1 : 0;
+
+ if (lcd == get_lcd_state())
+ return 0;
+
+ if(lcd_switch_handle) {
+ status = acpi_evaluate_object(lcd_switch_handle,
+ NULL, NULL, NULL);
+
+ if (ACPI_FAILURE(status))
+ printk(ASUS_WARNING "Error switching LCD\n");
+ }
+
+ write_status(NULL, lcd, LCD_ON, 0);
+ return 0;
+}
+
+static void lcd_blank(int blank)
+{
+ struct backlight_device *bd = asus_backlight_device;
+
+ if(bd) {
+ down(&bd->sem);
+ if(likely(bd->props)) {
+ bd->props->power = blank;
+ if(likely(bd->props->update_status))
+ bd->props->update_status(bd);
+ }
+ up(&bd->sem);
+ }
+}
+
+static int read_brightness(struct backlight_device *bd)
+{
+ int value;
+
+ if (!read_acpi_int(brightness_get_handle, NULL, &value, NULL))
+ printk(ASUS_WARNING "Error reading brightness\n");
+
+ return value;
+}
+
+static int set_brightness(struct backlight_device *bd, int value)
+{
+ int ret = 0;
+
+ value = (0 < value) ? ((15 < value) ? 15 : value) : 0;
+ /* 0 <= value <= 15 */
+
+ if (!write_acpi_int(brightness_set_handle, NULL, value, NULL)) {
+ printk(ASUS_WARNING "Error changing brightness\n");
+ ret = -EIO;
+ }
+
+ return ret;
+}
+
+static int update_bl_status(struct backlight_device *bd)
+{
+ int rv;
+ int value = bd->props->brightness;
+
+ rv = set_brightness(bd, value);
+ if(rv)
+ return rv;
+
+ value = (bd->props->power == FB_BLANK_UNBLANK) ? 1 : 0;
+ return set_lcd_state(value);
+}
+