The dependecies for BACKLIGHT_CLASS_DEVICE are defined a bit strange, but it seems one has to always select both BACKLIGHT_CLASS_DEVICE and BACKLIGHT_LCD_SUPPORT to avoid this error:
drivers/gpu/drm/tilcdc/tilcdc_panel.c:396: undefined reference to `of_find_backlight_by_node'
Cc: Rob Clark robdclark@gmail.com Cc: dri-devel@lists.freedesktop.org Cc: Dave Airlie airlied@redhat.com Signed-off-by: Arnd Bergmann arnd@arndb.de --- drivers/gpu/drm/tilcdc/Kconfig | 1 + 1 file changed, 1 insertion(+)
diff --git a/drivers/gpu/drm/tilcdc/Kconfig b/drivers/gpu/drm/tilcdc/Kconfig index e461e99..7a4d101 100644 --- a/drivers/gpu/drm/tilcdc/Kconfig +++ b/drivers/gpu/drm/tilcdc/Kconfig @@ -6,6 +6,7 @@ config DRM_TILCDC select DRM_GEM_CMA_HELPER select VIDEOMODE_HELPERS select BACKLIGHT_CLASS_DEVICE + select BACKLIGHT_LCD_SUPPORT help Choose this option if you have an TI SoC with LCDC display controller, for example AM33xx in beagle-bone, DA8xx, or