Procure por /boot/config<...>
file (pertence ao pacote kernel deb). Suporte CAN está habilitado em Wheezy:
CONFIG_CAN=m
CONFIG_CAN_RAW=m
CONFIG_CAN_BCM=m
CONFIG_CAN_GW=m
#
# CAN Device Drivers
#
CONFIG_CAN_VCAN=m
CONFIG_CAN_SLCAN=m
CONFIG_CAN_DEV=m
CONFIG_CAN_CALC_BITTIMING=y
CONFIG_CAN_MCP251X=m
CONFIG_PCH_CAN=m
CONFIG_CAN_SJA1000=m
# CONFIG_CAN_SJA1000_PLATFORM is not set
CONFIG_CAN_EMS_PCMCIA=m
CONFIG_CAN_EMS_PCI=m
CONFIG_CAN_PEAK_PCI=m
CONFIG_CAN_KVASER_PCI=m
CONFIG_CAN_PLX_PCI=m
# CONFIG_CAN_C_CAN is not set
#
# CAN USB interfaces
#
CONFIG_CAN_EMS_USB=m
CONFIG_CAN_ESD_USB2=m
CONFIG_CAN_SOFTING=m
CONFIG_CAN_SOFTING_CS=m
# CONFIG_CAN_DEBUG_DEVICES is not set