Comment # 3 on bug 937342 from Takashi Iwai

The culprit is:

[   27.030120] bluetooth hci0: Direct firmware load for
brcm/BCM20702A0-0a5c-21e6.hcd failed with error -2
[   27.030125] Bluetooth: hci0: BCM: patch brcm/BCM20702A0-0a5c-21e6.hcd not
found

So the firmware file is missing.  Still btusb driver tries to reload the
firmware at resume path, it fails again, and this resulted in such a warning. 
It's a long-standing known issue of the firmware loader core code.

That said, the warning and stack trace can be safely ignored.  But, the real
problem is that you have no firmware file, thus BT device might not work
properly.

Did you install kernel-firmware package?

Also, this should be irrelevant from other things.