MC7455/EM7455 dependencies and protocols
Dan Williams
dcbw at redhat.com
Tue Mar 7 20:51:20 UTC 2017
On Tue, 2017-03-07 at 12:34 -0800, Tim Harvey wrote:
> On Mon, Mar 6, 2017 at 3:01 PM, Dan Williams <dcbw at redhat.com> wrote:
> > On Mon, 2017-03-06 at 14:42 -0800, Tim Harvey wrote:
> > > On Sat, Mar 4, 2017 at 4:21 AM, Bjørn Mork <bjorn at mork.no> wrote:
> > > > [starting a new thread with the answers...]
> > >
> > > oops - my apologies for hijacking the previous thread.
> > >
> > > >
> > > > Tim Harvey <tharvey at gateworks.com> writes:
> > > >
> > > > > Hi Bjørn,
> > > > >
> > > > > Can you tell me more about how you got this modem working?
> > > > > I'm
> > > > > trying
> > > > > to understand:
> > > > > - what Linux drivers are required and do you have to inject
> > > > > new_id's
> > > > > vis sysfs to get them to probe (none of the drivers seem to
> > > > > recognize
> > > > > the 0x1199:0x9079 by default)
> > > >
> > > > Depending on the modem firmware configuration you may need
> > > > cdc_mbim,
> > > > qmi_wwan and qcserial.
> > > >
> > > > The 9079 PID is Lenovo specific, and AFAIK always in MBIM mode
> > > > by
> > > > default. The cdc_mbim driver matches on class attributes, so
> > > > there
> > > > is no
> > > > need for any device specific IDs.
> > > >
> > > > Wrt non-default configurations, both the 1199:9071 (Sierra
> > > > default)
> > > > and
> > > > 1199:9079 (Lenovo ID) were added to the qcserial and qmi_wwan
> > > > drivers in
> > > > Linux v4.5.
> > > >
> > > > > - what managment and communication dev nodes should be
> > > > > created
> > > >
> > > > Depends on modem firmware configuration. Typically one or more
> > > > /dev/cdc-wdmX nodes, one or more wwanY netdevs and zero or more
> > > > /dev/ttyUSBz nodes.
> > > >
> > > > > - what libqmi version is required
> > > >
> > > > The latest.
> > > >
> > > > > - what the difference is between mbim and qmi
> > > >
> > > > Different protocols for management and data framing. No need
> > > > to
> > > > worry
> > > > about that. The drivers and ModemManager will figure it out.
> > > >
> > > > But if you do want to worry, then Google has lots of
> > > > interesting
> > > > info :)
> > > >
> > > > > - what the firmware dependencies are, how to tell what
> > > > > firmware I
> > > > > have
> > > > > on them, and how to update if required
> > > >
> > > > ModemManager will tell you the firmware revision regardless of
> > > > protocols
> > > > and drivers in use. AFAIK, updating is not required for any
> > > > production MC7455/EM7455.
> > > >
> > > > > I've got an MC7455 as well as an EM7455 on hand to test with
> > > > > but
> > > > > haven't gotten either to be recognized by any of the Linux
> > > > > drivers (at
> > > > > least in 4.4).
> > > >
> > > > You'll need Linux v4.5 or later for QMI on these modems.
> > > >
> > > > And you'll probably need v4.7 or later for MBIM. Or one of the
> > > > stable
> > > > kernels with a backport of c086e7096170 ("cdc_ncm: workaround
> > > > for
> > > > EM7455
> > > > "silent" data interface"), for example v4.4.16 or later.
> > > >
> > >
> > > Thank you this was very helpful! I'm glad I asked before spending
> > > a
> > > lot of time with Linux 4.4.
> > >
> > > I've built a 4.10 kernel and do see the following for the
> > > 1199:9079
> > > EM7455
> > > - /dev/cdc-wdm0 management device from cdc_mbim (2 of them for
> > > 1199:9071 MC7455)
> > > - wwan0 registered net device from cdc_mbim
> > > - /dev/ttyUSB0,1,2 devices from qcserial
> > >
> > > I believe this confirms that the modem is using MBIM. It would
> > > seem
> > > that I should be using libmbim/mbimcli but then it also looks
> > > like
> > > libqmi has some MBIM support? In fact it looks like libqmi-
> > > 1.16.0+
> > > has
> > > added support for QMI-over-MBIM (requires libmbim-glib-
> > > 1.14.0+?)...
> > > perhaps this was to simplify applications like ModemManager so
> > > they
> > > only had to worry about one API?
> >
> > Not really. It turns out that some modems require QMI commands to
> > power up (the FCC Auth thing) that are non-standard, and thus
> > aren't
> > part of the standard MBIM spec. So ModemManager just uses the QMI-
> > in-
> > MBIM thing to send that command, and then proceeds to use MBIM for
> > the
> > rest.
> >
> > Yes, MM could skip MBIM and use QMI all the way, but that's
> > fighting
> > against a tide. If the modem comes up in MBIM mode, we assume
> > that's
> > what the manufacturer intended. That's also probably what Windows
> > does,
> > and the manufacturer probably tests with MBIM, and the connection
> > manager uses MBIM, so Linux and MM should too. That way we don't
> > try
> > to use buggy behavior the manufacturer never intended or tested.
> >
> > > I've built libmbim-1.14.0 and libqmi-1.17.901 (from source
> > > tarballs)
> > > and seem to be able to communicate with the modem now (I get sane
> > > responses for things like --dms-get-model) but I still can't
> > > connect
> > > without error using qmi-network.
> >
> > You wouldn't use qmi-network for this, you'd use mbim-network
> > instead.
> > Basically does the same thing, but with MBIM not QMI. Doesn't
> > guarantee you'll be successful, but at least follows the path of
> > least
> > resistance.
> >
> > Might be interesting to see what MBIM says if the data connection
> > fails.
> >
>
> Dan,
>
> Thanks for the explanation. Adding libmbim-devel cc
>
> What is the fundamental difference between the various cdc_wdm
> devices
> - is it modem/firmware specific which one is for what?
Specifically for different cdc-wdm devices exposed by a single *QMI*
modem, they all basically do the same thing, but are used for different
control/data pairs. So theoretically, if you want to have two IP
connections to different APNs at the same time (eg, one for normal data
and another for IMS) each connection would use a different cdc-
wdmX/wwanX pair. Qualcomm has changed that somewhat and has introduced
"muxing" where this is all done on a single pair.
> Here are some details about my system/software:
> - Board: Gateworks Ventana IMX6 based with USB2.0 to miniPCIe socket
> (for MC7455) and USB2.0 to M.2 socket (for EM7455)
> - Linux 4.10.0
> - libmbim 1.14.0
> - libqmi 1.17.901
> - MC7455: 1199:9071
> - EM7455: 1199:9079
> - I'm not testing with both cards present... testing one at a time on
> different boards
>
> MC7455:
> root at ventana:~# dmesg | egrep -ie qualcom\|mbim\|sierra\|wdm
> [ 13.247619] usbcore: registered new interface driver cdc_wdm
> [ 13.263903] qmi_wwan 1-1.2:1.8: cdc-wdm0: USB WDM device
> [ 13.264564] usbserial: USB Serial support registered for Qualcomm
> USB modem
> [ 13.273389] qmi_wwan 1-1.2:1.10: cdc-wdm1: USB WDM device
> [ 13.275348] qcserial 1-1.2:1.0: Qualcomm USB modem converter
> detected
> [ 13.276240] usb 1-1.2: Qualcomm USB modem converter now attached
> to ttyUSB0
> [ 13.277736] qcserial 1-1.2:1.2: Qualcomm USB modem converter
> detected
> [ 13.278354] usb 1-1.2: Qualcomm USB modem converter now attached
> to ttyUSB1
> [ 13.278846] qcserial 1-1.2:1.3: Qualcomm USB modem converter
> detected
> [ 13.279451] usb 1-1.2: Qualcomm USB modem converter now attached
> to ttyUSB2
> root at ventana:~# qmicli -d /dev/cdc-wdm0 --dms-get-firmware-preference
> firmware preference successfully retrieved:
> [image 0]
> Image type: 'modem'
> Unique ID: '002.007_001'
> Build ID: '02.08.02.00_GENERIC'
> [image 1]
> Image type: 'pri'
> Unique ID: '002.007_001'
> Build ID: '02.08.02.00_GENERIC'
> root at ventana:~# qmicli -d /dev/cdc-wdm0 --dms-swi-get-current-
> firmware
> [/dev/cdc-wdm0] Successfully retrieved current firmware:
> Model: MC7455
> Boot version: SWI9X30C_02.08.02.00
> AMSS version: SWI9X30C_02.08.02.00
> SKU ID: 1102476
> Package ID: unknown
> Carrier ID: 1
> Config version: 002.007_001
> root at ventana:~# mbimcli -d /dev/cdc-wdm0 --query-device-caps
> ^^^^ hangs here as well as any mbimcli cmd I've tried regardless of
> which wdm device
>
> Any idea what's going on here? I have two MC7455's and both behave
> the same.
Yeah. These MC7455 devices are in QMI mode, which is why mbimcli
doesn't work. Your EM7455 is in MBIM mode, which is why it does work
there.
> The EM7455 does not have this issue:
> root at ventana:~# qmicli -d /dev/cdc-wdm0 --dms-get-firmware-preference
>
qmicli has some logic to automatically detect that the device is using
MBIM mode, and then do the QMI-over-MBIM thing automatically for you.
Look at the driver binding from 'dmesg'. That will always tell you
what driver the kernel has chosen for each device, and thus what mode
its in.
Dan
> firmware preference successfully retrieved:
> [image 0]
> Image type: 'modem'
> Unique ID: '002.007_000'
> Build ID: '02.08.02.00_GENERIC'
> [image 1]
> Image type: 'pri'
> Unique ID: '002.007_000'
> Build ID: '02.08.02.00_GENERIC'
> root at ventana:~# qmicli -d /dev/cdc-wdm0 --dms-swi-get-current-
> firmware
> [/dev/cdc-wdm0] Successfully retrieved current firmware:
> Model: EM7455
> Boot version: SWI9X30C_02.08.02.00
> AMSS version: SWI9X30C_02.08.02.00
> SKU ID: 1102782
> Package ID: unknown
> Carrier ID: 1
> Config version: 002.007_000
> root at ventana:~# mbimcli -d /dev/cdc-wdm0 --query-device-caps
> [/dev/cdc-wdm0] Device capabilities retrieved:
> Device type: 'remote'
> Cellular class: 'gsm'
> Voice class: 'no-voice'
> Sim class: 'removable'
> Data class: 'umts, hsdpa, hsupa, lte'
> SMS caps: 'pdu-receive, pdu-send'
> Ctrl caps: 'reg-manual'
> Max sessions: '8'
> Custom data class: 'unknown'
> Device ID: '014582002248145'
> Firmware info: 'SWI9X30C_02.08.02.00'
> Hardware info: 'EM7455'
> root at ventana:~# mbimcli -d /dev/cdc-wdm0 --query-subscriber-ready-
> status
> [/dev/cdc-wdm0] Subscriber ready status retrieved:
> Ready state: 'sim-not-inserted'
> Subscriber ID: 'unknown'
> SIM ICCID: 'unknown'
> Ready info: 'unknown'
> Telephone numbers: (0) 'unknown'
> ^^^^ haven't gotten a SIM on this device yet so can't go further -
> working on this
>
> Thanks,
>
> Tim
>
> > Dan
> >
> > > I've queried the following from the MC7455:
> > > # qmicli -d /dev/cdc-wdm0 --dms-get-manufacturer
> > > [/dev/cdc-wdm0] Device manufacturer retrieved:
> > > Manufacturer: 'Sierra Wireless, Incorporated'
> > > # qmicli -d /dev/cdc-wdm0 --dms-get-model
> > > [/dev/cdc-wdm0] Device model retrieved:
> > > Model: 'MC7455'
> > > # qmicli -d /dev/cdc-wdm0 --dms-get-operating-mode
> > > [/dev/cdc-wdm0] Operating mode retrieved:
> > > Mode: 'online'
> > > HW restricted: 'no'
> > > # qmicli -d /dev/cdc-wdm0 --dms-get-activation-state
> > > [/dev/cdc-wdm0] Activation state retrieved:
> > > State: 'not-activated'
> > > # qmicli -d /dev/cdc-wdm0 --nas-get-signal-strength
> > > [/dev/cdc-wdm0] Successfully got signal strength
> > > Current:
> > > Network 'umts': '-81 dBm'
> > > RSSI:
> > > Network 'umts': '-81 dBm'
> > > ECIO:
> > > Network 'umts': '-14.0 dBm'
> > > IO: '-106 dBm'
> > > SINR (8): '9.0 dB'
> > > # qmicli -d /dev/cdc-wdm0 --nas-get-signal-info
> > > [/dev/cdc-wdm0] Successfully got signal info
> > > WCDMA:
> > > RSSI: '-81 dBm'
> > > ECIO: '-12.0 dBm'
> > >
> > > I've set my APN in /etc/qmi-network.conf yet 'qmi-network
> > > /dev/cdc-wdm0 start' fails:
> > > error: couldn't start network: QMI protocol error (14):
> > > 'CallFailed'
> > > call end reason (1): generic-unspecified
> > > verbose call end reason (3,2504): [cm] (null)
> > > Saving state at /tmp/qmi-network-state-cdc-wdm0... (CID: 35)
> > > error: network start failed, no packet data handle
> > > Clearing state at /tmp/qmi-network-state-cdc-wdm0...
> > >
> > > What is the best method to troubleshoot to determine if the issue
> > > is
> > > with the SIM, signal strength, APN configuration, etc?
> > >
> > > Regards,
> > >
> > > Tim
> > >
> > > >
> > > >
> > > > Bjørn
> > >
> > > _______________________________________________
> > > libqmi-devel mailing list
> > > libqmi-devel at lists.freedesktop.org
> > > https://lists.freedesktop.org/mailman/listinfo/libqmi-devel
>
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