Check your system.log for output from BrcmPatchRAM. You should not see BrcmPatchRAM2 resident in ioreg like that. The firmware upload process is an "upload and go away" kind of process. Usually takes 1-2 seconds.
This is what is see in my system.log:
puter kernel[0]: BrcmPatchRAM2: Version 2.2.3 starting on OS X Darwin 15.3.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: [0a5c:21e8]: USB [5CF370778E3D v274] "BCM920702 Bluetooth 4.0" by "Broadcom Corp"
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: [0a5c:21e8]: Firmware upgrade not needed.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: [0a5c:21e8]: Published new IOKit personality.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: Processing time 0.4 seconds.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: Version 2.2.3 starting on OS X Darwin 15.3.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: [0a5c:21e8]: USB [5CF370778E3D v274] "BCM920702 Bluetooth 4.0" by "Broadcom Corp"
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: [0a5c:21e8]: Firmware upgrade not needed.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: [0a5c:21e8]: Published new IOKit personality.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: Processing time 0.4 seconds.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: Version 2.2.3 starting on OS X Darwin 15.3.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: [0a5c:21e8]: USB [5CF370778E3D v274] "BCM920702 Bluetooth 4.0" by "Broadcom Corp"
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: [0a5c:21e8]: Firmware upgrade not needed.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: [0a5c:21e8]: Published new IOKit personality.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: Processing time 0.4 seconds.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: Version 2.2.3 starting on OS X Darwin 15.3.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: [0a5c:21e8]: USB [5CF370778E3D v274] "BCM920702 Bluetooth 4.0" by "Broadcom Corp"
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: [0a5c:21e8]: Firmware upgrade not needed.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: [0a5c:21e8]: Published new IOKit personality.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: Processing time 0.4 seconds.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: Version 2.2.3 starting on OS X Darwin 15.3.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: [0a5c:21e8]: USB [5CF370778E3D v274] "BCM920702 Bluetooth 4.0" by "Broadcom Corp"
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: [0a5c:21e8]: Firmware upgrade not needed.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: [0a5c:21e8]: Published new IOKit personality.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: Processing time 0.4 seconds.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: Version 2.2.3 starting on OS X Darwin 15.3.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: [0a5c:21e8]: USB [5CF370778E3D v274] "BCM920702 Bluetooth 4.0" by "Broadcom Corp"
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: [0a5c:21e8]: Firmware upgrade not needed.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: [0a5c:21e8]: Published new IOKit personality.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: Processing time 0.4 seconds.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: Version 2.2.3 starting on OS X Darwin 15.3.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: [0a5c:21e8]: USB [5CF370778E3D v274] "BCM920702 Bluetooth 4.0" by "Broadcom Corp"
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: [0a5c:21e8]: Firmware upgrade not needed.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: [0a5c:21e8]: Published new IOKit personality.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: Processing time 0.4 seconds.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: Version 2.2.3 starting on OS X Darwin 15.3.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: [0a5c:21e8]: USB [5CF370778E3D v274] "BCM920702 Bluetooth 4.0" by "Broadcom Corp"
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: [0a5c:21e8]: Firmware upgrade not needed.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: [0a5c:21e8]: Published new IOKit personality.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: Processing time 0.4 seconds.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: Version 2.2.3 starting on OS X Darwin 15.3.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: [0a5c:21e8]: USB [5CF370778E3D v274] "BCM920702 Bluetooth 4.0" by "Broadcom Corp"
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: [0a5c:21e8]: Firmware upgrade not needed.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: [0a5c:21e8]: Published new IOKit personality.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: Processing time 0.4 seconds.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: Version 2.2.3 starting on OS X Darwin 15.3.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: [0a5c:21e8]: USB [5CF370778E3D v274] "BCM920702 Bluetooth 4.0" by "Broadcom Corp"
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: [0a5c:21e8]: Firmware upgrade not needed.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: [0a5c:21e8]: Published new IOKit personality.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: Processing time 0.3 seconds.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: Version 2.2.3 starting on OS X Darwin 15.3.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: [0a5c:21e8]: USB [5CF370778E3D v274] "BCM920702 Bluetooth 4.0" by "Broadcom Corp"
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: [0a5c:21e8]: Firmware upgrade not needed.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: [0a5c:21e8]: Published new IOKit personality.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: Processing time 0.4 seconds.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: Version 2.2.3 starting on OS X Darwin 15.3.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: [0a5c:21e8]: USB [5CF370778E3D v274] "BCM920702 Bluetooth 4.0" by "Broadcom Corp"
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: [0a5c:21e8]: Firmware upgrade not needed.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: [0a5c:21e8]: Published new IOKit personality.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: Processing time 0.4 seconds.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: Version 2.2.3 starting on OS X Darwin 15.3.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: [0a5c:21e8]: USB [5CF370778E3D v274] "BCM920702 Bluetooth 4.0" by "Broadcom Corp"
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: [0a5c:21e8]: Firmware upgrade not needed.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: [0a5c:21e8]: Published new IOKit personality.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: Processing time 0.4 seconds.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: Version 2.2.3 starting on OS X Darwin 15.3.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: [0a5c:21e8]: USB [5CF370778E3D v274] "BCM920702 Bluetooth 4.0" by "Broadcom Corp"
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: [0a5c:21e8]: Firmware upgrade not needed.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: [0a5c:21e8]: Published new IOKit personality.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: Processing time 0.4 seconds.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: Version 2.2.3 starting on OS X Darwin 15.3.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: [0a5c:21e8]: USB [5CF370778E3D v274] "BCM920702 Bluetooth 4.0" by "Broadcom Corp"
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: [0a5c:21e8]: Firmware upgrade not needed.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: [0a5c:21e8]: Published new IOKit personality.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: Processing time 0.4 seconds.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: Version 2.2.3 starting on OS X Darwin 15.3.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: [0a5c:21e8]: USB [5CF370778E3D v274] "BCM920702 Bluetooth 4.0" by "Broadcom Corp"
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: [0a5c:21e8]: Firmware upgrade not needed.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: [0a5c:21e8]: Published new IOKit personality.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: Processing time 0.4 seconds.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: Version 2.2.3 starting on OS X Darwin 15.3.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: [0a5c:21e8]: USB [5CF370778E3D v274] "BCM920702 Bluetooth 4.0" by "Broadcom Corp"
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: [0a5c:21e8]: Firmware upgrade not needed.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: [0a5c:21e8]: Published new IOKit personality.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: Processing time 0.4 seconds.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: Version 2.2.3 starting on OS X Darwin 15.3.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: [0a5c:21e8]: USB [5CF370778E3D v274] "BCM920702 Bluetooth 4.0" by "Broadcom Corp"
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: [0a5c:21e8]: Firmware upgrade not needed.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: [0a5c:21e8]: Published new IOKit personality.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: Processing time 0.4 seconds.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: Version 2.2.3 starting on OS X Darwin 15.3.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: [0a5c:21e8]: USB [5CF370778E3D v274] "BCM920702 Bluetooth 4.0" by "Broadcom Corp"
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: [0a5c:21e8]: Firmware upgrade not needed.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: [0a5c:21e8]: Published new IOKit personality.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: Processing time 0.4 seconds.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: Version 2.2.3 starting on OS X Darwin 15.3.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: [0a5c:21e8]: USB [5CF370778E3D v274] "BCM920702 Bluetooth 4.0" by "Broadcom Corp"
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: [0a5c:21e8]: Firmware upgrade not needed.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: [0a5c:21e8]: Published new IOKit personality.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: Processing time 0.4 seconds.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: Version 2.2.3 starting on OS X Darwin 15.3.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: [0a5c:21e8]: USB [5CF370778E3D v274] "BCM920702 Bluetooth 4.0" by "Broadcom Corp"
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: [0a5c:21e8]: Firmware upgrade not needed.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: [0a5c:21e8]: Published new IOKit personality.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: Processing time 0.4 seconds.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: Version 2.2.3 starting on OS X Darwin 15.3.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: [0a5c:21e8]: USB [5CF370778E3D v274] "BCM920702 Bluetooth 4.0" by "Broadcom Corp"
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: [0a5c:21e8]: Firmware upgrade not needed.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: [0a5c:21e8]: Published new IOKit personality.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: Processing time 0.4 seconds.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: Version 2.2.3 starting on OS X Darwin 15.3.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: [0a5c:21e8]: USB [5CF370778E3D v274] "BCM920702 Bluetooth 4.0" by "Broadcom Corp"
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: [0a5c:21e8]: Firmware upgrade not needed.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: BrcmPatchRAM2: [0a5c:21e8]: Published new IOKit personality.
Apr 3 13:07:43 Deees-maiii-computer kernel[0]: *** kernel exceeded 500 log message per second limit - remaining messages this second discarded ***
It hangs at this message, then repeats itself over again...