nouveau: support backlight only when kernel does

Loading nouveau.ko would fail with unknown symbols, if the backlight
class device support is not provided in the kernel. Let's make the
backlight support dependant on the kernel configuration.

This is a bit ugly, the proper way would be to check for the config in
Makefile.kernel whether to build nouveau_backlight.o at all, and if not,
nouveau_drv.h should provide the stubs.

Signed-off-by: Pekka Paalanen <pq@iki.fi>

diff --git a/linux-core/nouveau_backlight.c b/linux-core/nouveau_backlight.c
index 32bb3e5..51c747a 100644 (file)
--- a/linux-core/nouveau_backlight.c
+++ b/linux-core/nouveau_backlight.c
@@ -37,6 +37,8 @@
 #include "nouveau_drm.h"
 #include "nouveau_reg.h"
 
+#ifdef CONFIG_BACKLIGHT_CLASS_DEVICE
+
 static int nv40_get_intensity(struct backlight_device *bd)
 {
        struct drm_device *dev = bl_get_data(bd);
@@ -157,4 +159,17 @@ void nouveau_backlight_exit(struct drm_device *dev)
 
        if (dev_priv->backlight)
                backlight_device_unregister(dev_priv->backlight);
-}      
+}
+
+#else /* CONFIG_BACKLIGHT_CLASS_DEVICE not set */
+int nouveau_backlight_init(struct drm_device *dev)
+{
+       (void)dev;
+       return 0;
+}
+
+void nouveau_backlight_exit(struct drm_device *dev)
+{
+       (void)dev;
+}
+#endif /* CONFIG_BACKLIGHT_CLASS_DEVICE not set */