Drivers that call v4l2_async_nf_init() need to select the corresponding Kconfig symbol: ERROR: modpost: "v4l2_async_nf_init" [drivers/media/platform/marvell/cafe_ccic.ko] undefined! ERROR: modpost: "__v4l2_async_nf_add_i2c" [drivers/media/platform/marvell/cafe_ccic.ko] undefined! ERROR: modpost: "v4l2_async_nf_unregister" [drivers/media/platform/marvell/mcam-core.ko] undefined! ERROR: modpost: "v4l2_async_nf_init" [drivers/media/platform/marvell/mmp_camera.ko] undefined! ERROR: modpost: "__v4l2_async_nf_add_fwnode_remote" [drivers/media/platform/marvell/mmp_camera.ko] undefined! I checked all v4l2 drivers to see if anything else has the same bug, but these two appear to be the only ones. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com> Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>