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Sierra 3G modem in Linux 3.14.28

Question asked by fang on Apr 30, 2016
Latest reply on Apr 30, 2016 by igorpadykov

Sierra MC8705 modem works fine in Linux 3.10.53 (Sierra_net.c V3.2)

Using this modem on our board(imx6Q SabreSD board), it works in the field for over one year.

 

Last week I upgraded Linux to 3.14.28(imx_3.14.28_1.0.0_ga) (Sierra_net.c V3.2).

After that, modem is detected but it doesn't work.

 

    # ifconfig wwan0

    ifconfig: wwan0: error fetching interface information: Device not found

 

    # dmesg | grep -e sierra -e Sierra

    [    5.009833] usbcore: registered new interface driver sierra

    [    5.016359] usbserial: USB Serial support registered for Sierra USB modem

    [    5.025902] sierra 1-1.2:1.0: Sierra USB modem converter detected

    [    5.068022] usb 1-1.2: Sierra USB modem converter now attached to ttyUSB0

    [    5.076418] sierra 1-1.2:1.1: Sierra USB modem converter detected

    [    5.085750] usb 1-1.2: Sierra USB modem converter now attached to ttyUSB1

    [    5.095794] sierra 1-1.2:1.2: Sierra USB modem converter detected

    [    5.107202] usb 1-1.2: Sierra USB modem converter now attached to ttyUSB2

    [    5.121224] sierra 1-1.2:1.3: Sierra USB modem converter detected

    [    5.132774] usb 1-1.2: Sierra USB modem converter now attached to ttyUSB3

    [    5.143377] sierra 1-1.2:1.4: Sierra USB modem converter detected

    [    5.152881] usb 1-1.2: Sierra USB modem converter now attached to ttyUSB4

 

    # lsusb

    Bus 001 Device 003: ID 1199:68a3 Sierra Wireless, Inc. MC8700 Modem

    Bus 001 Device 002: ID 0424:2412 Standard Microsystems Corp.

    Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

 

    # cat /dev/ttyUSB3

    +CREG: 2,1,"2252","014C0E9E",2

    OK

    *CNTI: 0,UMTS

    OK

    ...

 

    # dmesg | grep -e pci -e PCI

    [    0.235767] PCI: CLS 0 bytes, default 64

    [    1.403808] imx6q-pcie 1ffc000.pcie: phy link never came up

    [    1.403827] imx6q-pcie 1ffc000.pcie: Failed to bring link up!

    [    1.403858] imx6q-pcie 1ffc000.pcie: failed to initialize host

    [    1.403908] imx6q-pcie: probe of 1ffc000.pcie failed with error -22

    [    2.690746] ehci-pci: EHCI PCI platform driver

 

    I use the same SIM card, board, modem and rootfs as I tested on Linux 3.10.53.

    Yesterday I read many threads related to modem in this community, and tried below:

    1. Add more delay in imx6_pcie_wait_for_link in pci-imx6.c:

        change to usleep_range(100, 1000), or chang count = 10000

    2. Disable CONFIG_PCI_MSI

    3. Remove #address_cells; #size_cells of intc in imx6qdl.dtsi

 

    it still no wwan0 interface.

    I'm really appreciate if someone can give me some idea.

 

    PS. Is there any official released patches for Linux imx_3.14.28_1.0.0_ga?

 

    Thanks.

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