Re: Custom device plugin

[Kirill Elagin <kirelagin gmail com>]

> I'll assume these are the Yota LTE (LU150?) USB sticks based on the GCT
> chipset, vid 1076

That's right.


> pid 8003.  If not please elighten me :)

At least my modem has pid 8002.


> I'm happy to take a patch for these devices, but first we'd want a bit
> more information about it.  How do they communicate with the host?  Does
> the host actually need to configure them at all, or is the configuration
> all done through the device's web interface?

They use RNDIS, so the host sees them as network interfaces (the
driver is rndis_host).

lsusb:
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  bDeviceClass            2 Communications
  idVendor           0x1076 GCT Semiconductor, Inc.
  idProduct          0x8002
  iManufacturer           1 GCT SEMICONDUCTOR Inc
  iProduct                2 Modem Yota
      bInterfaceClass       224 Wireless
      bInterfaceSubClass      1 Radio Frequency
      bInterfaceProtocol      3 RNDIS
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

dmesg:
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
[37908.902059] usb 2-1: new high-speed USB device number 5 using ehci_hcd
[37909.016784] usb 2-1: New USB device found, idVendor=1076, idProduct=8001
[37909.016790] usb 2-1: New USB device strings: Mfr=1, Product=2, SerialNumber=0
[37909.016795] usb 2-1: Product: Modem Yota
[37909.016799] usb 2-1: Manufacturer: GCT SEMICONDUCTOR Inc
[37909.017941] scsi7 : usb-storage 2-1:1.0
[37910.020806] scsi 7:0:0:0: CD-ROM            GDM Mass
       PQ: 0 ANSI: 0 CCS
[37910.040402] sr1: scsi3-mmc drive: 0x/0x caddy
[37910.040821] sr 7:0:0:0: Attached scsi CD-ROM sr1
[37911.023887] usb 2-1: USB disconnect, device number 5
[37911.780107] usb 2-1: new high-speed USB device number 6 using ehci_hcd
[37911.894782] usb 2-1: New USB device found, idVendor=1076, idProduct=8002
[37911.894788] usb 2-1: New USB device strings: Mfr=1, Product=2, SerialNumber=0
[37911.894792] usb 2-1: Product: Modem Yota
[37911.894796] usb 2-1: Manufacturer: GCT SEMICONDUCTOR Inc
[37911.895640] rndis_host 2-1:1.0: dev can't take 1558 byte packets
(max 1458), adjusting MTU to 1400
[37911.896799] rndis_host 2-1:1.0: eth1: register 'rndis_host' at
usb-0000:00:1d.7-1, RNDIS device, 00:09:3b:f0:1a:40
[37911.910891] systemd-udevd[14153]: renamed network interface eth1 to yota
[37922.034017] yota: no IPv6 routers present
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

The device seems to contain a DHCP-server that always provides the
same settings: 10.0.0.10/24 gw/dns 10.0.0.1.
The server is rather buggy so I've sticked to static IP configuration in NM.

You can't really configure it — it just works. Through the web
interface you can check connection status,
update firmware (they say, you won't need this, because it will be
updated automatically), and
switch the device on/off (the relevant code is commented out in HTML
for some reason, though it does work).

Web GUI gets status from http://10.0.0.1/status. I bet, their software
for Windows and Mac
gets data the same way.The data looks like this:
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
InterfaceType=lte
3GPP.IMSI=<not really interesting>
3GPP.UICC-ID=<not really interesting>
3GPP.IMEI=<not really interesting>
3GPP.IMEISV=<not really interesting>
DeviceName=Modem Yota
RfVersion=no information
AsicVersion=GDM7240R1
FirmwareVersion=3.7
State=Connected
UpdateState=NotStarted
UpdateProgress=0
ConnectedTime=894
3GPP.SINR=4
3GPP.RSSI=-86
3GPP.MCC=250
3GPP.MNC=11
3GPP.PLMN=25011
3GPP.RoamingStatus=0
3GPP.CGI=25011BF2A900
3GPP.CI=BF2A900
3GPP.eNBID=BF2A9
3GPP.HNBN=
3GPP.CSGT=
3GPP.CenterFreq=2642500
3GPP.TxPWR=23.0
3GPP.SPN=Yota
SessionID=3420730
3GPP.IsIdle=0
IP=10.138.173.239
SubnetMask=255.255.255.0
DefaultGateway=10.0.0.1
DHCP=10.0.0.1
DNS=10.0.0.1
SentBytes=97808
ReceivedBytes=253845
MaxDownlinkThroughput=99232
MaxUplinkThroughput=88064
CurDownlinkThroughput=53480
CurUplinkThroughput=13048
TotalHandoversCount=0
SucceededHandoversCount=0
NewFirmwareVersion=
3GPP.RSRP=-116
3GPP.RSRQ=-11.0
MSISDN=
SupportsConnectDisabling=0
CQI=8
DownlinkMCSMain=3,9,6
DownlinkMCSDiv=3,6,4
UplinkMCS=3,4,2
NBRi=earfcn,ci,rsrp
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

--
Кирилл Елагин