I have always upgraded CP phones by placing the relevant files onto my tftp system, holing down # on the phone whilst plugging in the PoE connection and then typing the reset key sequence, after which the phone pops off and finds the files and upgrades
I have a CP-8945 with SCCP 22.214.171.124... I am trying the same thing, I have downloaded the zip file and placed the 10 or so files onto my tftp system..
first problem is that the # plus sequence doesn't seem to do anything, the lights don't go off as describe by Cisco so I waited until the phones booted and di a soft key factory reset
still the phone doesn't upgrade like I usually see with other models
according to Cisco you should be able to upgrade without the need for a call manager as see in the link below
•cmterm-894x-sccp.9-2-3-5.zip (for SCCP firmware)
•cmterm-894x-sip.9-2-3-5.zip (for SIP firmware)
What am I doing wrong please ?