[RFC] Initial support for the new MC74XX modules

[Bjørn Mork]

Aleksander Morgado <aleksander at aleksander.es> writes:

> The UIM service changes missing are quite a lot (and complex), truth
> be told, so it may take a while until all are ready to land in git
> master... I may actually end up changing the default logic to use UIM
> if supported, and DMS UIM otherwise, not sure.

Yes, I believe that makes sense.  The UIM functions should work fine if
implemented.

Let me just queue up a few more feature requests while we're at it :)

I noticed that Sierra has implemented a nice carrier aggregation
display.  This is the normal (without aggregation) state:

bjorn at nemi:~$ mmcli -m 0 --command='AT!GSTATUS?'
response: '!GSTATUS: 
Current Time:  9591             Temperature: 41
Bootup Time:   0                Mode:        ONLINE         
System mode:   LTE              PS state:    Attached     
LTE band:      B7               LTE bw:      20 MHz  
LTE Rx chan:   3050             LTE Tx chan: 21050
LTE CA state:  INACTIVE    
EMM state:     Registered       Normal Service 
RRC state:     RRC Releasing  
IMS reg state: No Srv  

PCC RxM RSSI:  -63              RSRP (dBm):  -90
PCC RxD RSSI:  -61              RSRP (dBm):  -88
Tx Power:      0                TAC:         78BF (30911)
RSRQ (dB):     -6               Cell ID:     01036701 (17000193)
SINR (dB):     19.2'


You see "LTE CA state: INACTIVE" indicating support for CA, and that's
all.  But when aggregation is active, you get a bit more, including new
"SCC" RSSI and RSRP fields and of course the additional band and channel:

jorn at nemi:~$ mmcli -m 0 --command='AT!GSTATUS?'
response: '!GSTATUS: 
Current Time:  9621             Temperature: 43
Bootup Time:   0                Mode:        ONLINE         
System mode:   LTE              PS state:    Attached     
LTE band:      B7               LTE bw:      20 MHz  
LTE Rx chan:   3050             LTE Tx chan: 21050
LTE CA state:  ACTIVE                   LTE Scell band:B3     
LTE Scell bw:20 MHz             LTE Scell chan:1450
EMM state:     Registered       Normal Service 
RRC state:     RRC Connected  
IMS reg state: No Srv  

PCC RxM RSSI:  -60              RSRP (dBm):  -91
PCC RxD RSSI:  -57              RSRP (dBm):  -88
SCC RxM RSSI:  -49              RSRP (dBm):  -78
SCC RxD RSSI:  -51              RSRP (dBm):  -78
Tx Power:      13               TAC:         78BF (30911)
RSRQ (dB):     -9               Cell ID:     01036701 (17000193)
SINR (dB):     18.4'


It would be nice to have access to some of this info in libqmi/MM.  But
I don't even know where to get it from in QMI at the moment.  Will try
to figure out, but it's a bit of a hassle.  The only way I've found to
keep aggregation active is by using a lot of bandwidth.  And that tends
to eat my monthly quota really fast (35GB is all we get...).


Bjørn