OMAP: DSS2: Add method for querying display dimensions from DSS drivers

Add get_dimensions() to struct omap_dss_driver. Use the call, if supported
by the driver, in OMAPFB.

Signed-off-by: Jani Nikula <ext-jani.1.nikula@nokia.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
diff --git a/drivers/video/omap2/omapfb/omapfb-ioctl.c b/drivers/video/omap2/omapfb/omapfb-ioctl.c
index 3e4ee4d..cff4503 100644
--- a/drivers/video/omap2/omapfb/omapfb-ioctl.c
+++ b/drivers/video/omap2/omapfb/omapfb-ioctl.c
@@ -895,8 +895,16 @@
 
 		p.display_info.xres = xres;
 		p.display_info.yres = yres;
-		p.display_info.width = 0;
-		p.display_info.height = 0;
+
+		if (display->driver->get_dimensions) {
+			u32 w, h;
+			display->driver->get_dimensions(display, &w, &h);
+			p.display_info.width = w;
+			p.display_info.height = h;
+		} else {
+			p.display_info.width = 0;
+			p.display_info.height = 0;
+		}
 
 		if (copy_to_user((void __user *)arg, &p.display_info,
 					sizeof(p.display_info)))