Inspecting the 4.14.x configarch/arm/configs/bcmrpi_defconfigshows thatCONFIG_BT_HCIUART_BCMis not enabled, but is in 4.9.x. I believe this is caused bythiscommit introduced in 4.14, which added aCONFIG_BT_HCIUART_SERDEVdependency toCONFIG_BT_HCIUART_BCM.CONFIG_BT_HCIUART_SERDEVneedsCONFIG_...