It seems that this has been a known issue for all Broadcom BT devices in standard Ubuntu and the issue can be fixed if we simply pack the same solution (brcm installer) into standard Ubuntu. Or users are advised to refer to the instructions given in http://askubuntu.com/questions/533043/bluetooth-not-working-on-ubuntu-14-04-with-dell-inspiron-15-3521 and fix it by themselves.
It seems that this has been a known issue for all Broadcom BT devices in standard Ubuntu and the issue can be fixed if we simply pack the same solution (brcm installer) into standard Ubuntu. Or users are advised to refer to the instructions given in http:// askubuntu. com/questions/ 533043/ bluetooth- not-working- on-ubuntu- 14-04-with- dell-inspiron- 15-3521 and fix it by themselves.