drm/panel: ld9040: add backlight Kconfig dependency

The driver now uses the backlight interface, which breaks when that
is disabled:

ld.lld: error: undefined symbol: devm_backlight_device_register

Enforce the necessary Kconfig dependency to avoid this.

Fixes: c2268daa65fb ("drm/panel: ld9040: Register a backlight device")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Paul Cercueil <paul@crapouillou.net>
Link: https://patchwork.freedesktop.org/patch/msgid/20230724121736.1293270-1-arnd@kernel.org

diff --git a/drivers/gpu/drm/panel/Kconfig b/drivers/gpu/drm/panel/Kconfig
index 1a0fd07..05f9e80 100644 (file)
--- a/drivers/gpu/drm/panel/Kconfig
+++ b/drivers/gpu/drm/panel/Kconfig
@@ -300,6 +300,7 @@ config DRM_PANEL_LEADTEK_LTK500HD1829
 config DRM_PANEL_SAMSUNG_LD9040
        tristate "Samsung LD9040 RGB/SPI panel"
        depends on OF && SPI
+       depends on BACKLIGHT_CLASS_DEVICE
        select VIDEOMODE_HELPERS
 
 config DRM_PANEL_LG_LB035Q02