Uqmi not working

Hi,

I am trying to set up qmi for 4G connection. I have installed all the required libraries like: usb-modeswitch kmod-mii kmod-usb-net kmod-usb-wdm kmod-usb-net-qmi-wwan uqmi. Then I used LUCI to configure QMI cellular, these are my 4G config in network:

config interface '4G'                      
        option proto 'qmi'                 
        option apn 'myapn'
        option device '/dev/cdc-wdm0'

Then I used putty to ssh into my router, I and entered the commands like:
ifup 4G : this command skipped then goto next command.
uqmi -d /dev/cdc-wdm0 --get-data-status : this command just stalled until ctl-C
and any other commands that start with uqmi just stalled until ctl-C.

I think my qmi protocol hasnt been properly configured and activated.

Can anyone please give me a hint to get through this problem.

Thank you in advance.

Tony.

I am using Sierra MC7455 with ZBT WE826.

Please anyone can help me out?

Tony,

I found that I have to use kernel version 4.5 or better.
The kernel version I am having now is 4.4.42.

Can anyone help me how to upgrade to kernel version 4.5?

Tony