The Apple GMUX is the one managing the backlight, so there is no need for Nouveau to register its own backlight interface.
v2: Do not split information message on two lines as it prevents from grepping it, as pointed out by Hans de Goede Signed-off-by: Pierre Moreau <pierre.morrow at free.fr> --- drm/nouveau/nouveau_backlight.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drm/nouveau/nouveau_backlight.c b/drm/nouveau/nouveau_backlight.c index 41330e4..8429ceb 100644 --- a/drm/nouveau/nouveau_backlight.c +++ b/drm/nouveau/nouveau_backlight.c @@ -30,6 +30,7 @@ * Register locations derived from NVClock by Roderick Colenbrander */ +#include <linux/apple-gmux.h> #include <linux/backlight.h> #include <linux/idr.h> @@ -257,6 +258,11 @@ nouveau_backlight_init(struct drm_device *dev) struct nvif_device *device = &drm->device; struct drm_connector *connector; + if (apple_gmux_present()) { + NV_INFO(drm, "Apple GMUX detected: not registering Nouveau backlight interface"); + return 0; + } + INIT_LIST_HEAD(&drm->bl_connectors); list_for_each_entry(connector, &dev->mode_config.connector_list, head) { -- 2.8.2