Dell Latitude 7390

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Device Make/model Status Vendor ID / Product ID Kernel driver(s) Kernel version Notes
CPU Intel i7-8650U Works N/A N/A 5.6.6
Controller Intel Sunrise Point-LP Serial IO I2C Controller Works mfd_intel_lpss_{acpi/pci} 5.6.6 required for touchpad
Controller Intel Sunrise Point-LP Thermal subsystem Works intel_pch_thermal 5.6.6
Video Intel UHD Graphics 620 Works i915; linux-firmware (i915/kbl_dmc_v1_04.bin, i915/kbl_guc_33.0.0.bin, i915/kbl_huc_4.0.0.bin) 5.6.6
Audio Intel Device 9d71 Works snd_hda_intel 5.6.6
Ethernet Intel I219-LM Works e1000e 5.6.6
Wireless Intel Wireless 8265 / 8275 Works iwlwifi 5.6.6 linux-firmware wifi-8265-36.ucode
WWAN Dell DW5816E (rebadged Sierra Wireless EM7430) Works cdc_mbim or qmi_wwan and qcserial 5.6.13
Touchpad DLL07A8:01 044E:120B Works i2c_designware_{core,platform} 5.6.6 with alps/synaptics
Touchscreen Elan Microelectronics Touchscreen Works 04f3:254f usb_hid 5.6.6
SD Card reader Realtek RTS525A PCI Express Card Reader Works mfd_rtsx_pci, mmc_realtek_pci 5.6.6
Bluetooth Intel Bluetooth controller Works 8087:0a2b btusb 5.6.6
Webcam Realtek Integrated Webcam HD Works 0bda:568c uvcvideo (usb_video_class) 5.6.6
Smartcard Broadcom 5880 Not tested 0a5c:5832 app-crypt/ccid 5.6.6


Installed from Xubuntu booted in EFI mode.

Device Configuration


Firmware from the Linux firmware package will be necessary:

root #emerge --ask sys-kernel/linux-firmware

After emerging linux-firmware, the savedconfig file may be modified and the package re-emerged so that it only installs firmware required for the device. As an example:

FILE /etc/portage/savedconfig/sys-kernel/linux-firmware-20200421
# Remove files that shall not be installed from this list.

In order for this change to take effect, the savedconfig USE flag must be enabled.

root #echo 'sys-kernel/linux-firmware savedconfig' > /etc/portage/package.use/linux-firmware

And re-emerge the package:

root #emerge --ask sys-kernel/linux-firmware

Ensure that the Intel Wireless driver (iwlwifi) is built as a module to so that updated firmware can be found by the driver automatically.

The Intel video driver (i915) should also be built as a module for the reason listed above.

The i915 driver is known to cause freezes in modern (5.3+) kernels. The driver option intel_idle.max_cstate=1 may need to be set as a kernel command line parameter as a workaround until this is fixed. This option will impact on battery life as it prevents the processor from reaching deeper idle states.


To enable the i2c touchpad, set the following kernel options.

KERNEL Enable support for touchpad
Device Drivers  --->
     I2C support  ---> 
         I2C Hardware Bus support  --->
              <*> Synopsys DesignWare Platform
     Multifunction device drivers  --->
              <*> Intel Low Power Subsystem support in PCI mode
     HID support  --->
         Special HID drivers  --->
             <*> Alps HID device support
         I2C HID support  --->
             <*> HID over I2C transport layer

After that, the Synaptics article can be followed.

Altering the acpi_osi parameter may result in touchpads being not detected and as such, not working.

SD card reader

KERNEL Enable support for the SD card reader
Device Drivers  --->
     Multifunction device drivers  --->
         <*> Realtek PCI-E card reader
     <*> MMC/SD/SDIO card support  --->
         <*>   Realtek PCI-E SD/MMC Card Interface Driver


KERNEL Enable support for the webcam
Device Drivers  --->
    <*> Multimedia support  --->
        [*]   Media USB Adapters  --->.
            <*>   USB Video Class (UVC)

And add any users that need access to webcams to the video group to access the device: /dev/video0.

root #gpassword -a <user> video

SmartCard Reader

The SmartCard reader (BCM5880) is often locked into "CV" mode, meaning that it is set to operate only through the Dell ControlVault2 Windows application. To unlock the reader, use the script available here.

To use the reader, the ccid driver needs to be installed:

root #emerge --ask app-crypt/ccid

Once both of the above steps have been performed, the SmartCard reader should be visible using the pcsc_scan utility (sys-apps/pcsc-tools).


Modern kernels (5.6.13+, 5.4.41+, 4.19.123+) include support for the Dell Wireless 5816e in the cdc_mbim and qmi_wwan ethernet drivers, and the qc_serial interface driver.

To manage the WWAN card using ModemManager several kernel drivers are required:

Device Drivers  --->
     Network Device Support  ---> 
         <M> PPP (point-to-point protocol) support
         <M> PPP support for sync tty ports

The WWAN card can operate in either MBIM or QMI mode, and depending on USB composition will expose the following ports:

Composition DM NMEA AT Interface
6 - QMI Yes Yes Yes QMI
8 - MBIM Yes Yes Yes MBIM
9 - MBIM No No No MBIM

AT, NMEA and DM ports are /dev/ttyUSB interfaces that are provided by the qcserial driver:

  • The AT port is a Hayes command set (AT command) port, and can be used to control and check the status of the modem.
    • It is required in addition to the MBIM interface in order to establish a connection using GUI tools (Network Manager).
  • The NMEA port provides GPS NMEA strings, if enabled. The NMEA/GPS output can be enabled/disabled using AT commands.
  • The DM port is a serial diagnostic port.

The USB composition of the DW5816e can be changed using the script as long as the cdc-wdm0 interface is exposed in either MBIM or QMI mode. This will allow exposure the interface for the desired driver.

Both the cdc_mbim and qmi_wwan drivers will provide the /dev/cdc-wdm0 device.

MBIM and QMI are Ethernet over USB standards with an added signalling channel:
  • MBIM is the NCM (Network Control Model) protocol with an added signalling channel.
  • QMI is the ECM (Ethernet Control Model) protocol with an added signalling channel.

ECM is an earlier standard and has some issues with latency while NCM resolves those issues and is designed for high speed operation. More information is available here.

As MBIM is the more modern standard, it's assumed that this is in use going forward, however it's entirely possible to substitute libqmi for libmbim if QMI is chosen.

Before proceeding, ensure that the following interfaces exist in /dev:

  • cdc-wdm0 (MBIM/QMI)
  • ttyUSB0 (DM)
  • ttyUSB1 (NMEA)
  • ttyUSB2 (AT)
NetworkManager may need to be stopped and ModemManager killed to communicate with the modem over MBIM - try it if issues are encountered communicating with the device.

To test the modem is working, insert a SIM card, install libmbim and attempt to communicate with the device:

root #emerge --ask net-libs/libmbim
root #mbimcli -p -d /dev/cdc-wdm0 --query-device-caps

If the modem is working and configured correctly, a response should be received.

mbim-network can then be used to attempt to establish a network connection. If successful, the device should be managed by NetworkManager when the service is restarted. Ensure that the network is disconnected using mbim-network before attempting to manage the device with NetworkManager.

Firmware Updates

Firmware Updates for the DW5816e are available on the Sierra Wireless website.

The qmi-firmware-update utility is used to update the firmware of Sierra Wireless Qualcomm-based devices. The tool supports both MBIM and QMI drivers / interfaces. If the utility is not available, install it:

root #emerge --ask net-libs/libqmi

Determine the appropriate firmware version then download it and extract the firmware. There should be two files: a .cwe and a .nvu.

user $ls
SWI9X30C_02.33.03.00.cwe SWI9X30C_02.33.03.00_GENERIC_002.072_000.nvu

If ModemManager is running, it must be killed. If on OpenRC, stop the NetworkManager service first to prevent it from respawning:

root #rc-service NetworkManager stop
root #pidof ModemManager
root #kill 4000

Finally, navigate to the directory containing your firmware files and run qmi-firmware-update:

root #qmi-firmware-update -w /dev/cdc-wdm0 -u SWI9X30C_02.33.03.00.cwe SWI9X30C_02.33.03.00_GENERIC_002.072_000.nvu --device-open-mbim
This process involves rebooting the WWAN card into QDL mode (aka Download or Boot and Hold mode). In this mode the device reports a different device ID when enumerated (81cb instead of 81cc). This device ID is not currently supported by the qcserial driver causing the firmware update to fail. The qcserial driver will need to be patched and a new kernel built before this process will complete successfully until upstream accepts the patch.
In the event of an unsuccessful firmware update the device may be successfully communicated with, but will be unable to connect to networks using ModemManager. If this is the case, often the device is stuck attempting to restore from low-power mode and failing due to a mismatch between configured and installed firmwares. Running 'qmicli -d /dev/cdc-wdm0 -p --dms-list-stored-images' may prove useful for troubleshooting, as may the flags '--dms-select-stored-image=, --dms-get-firmware-preference, --dms-list-stored-images, and --dms-get-operating-mode' - This utility may be used in either MBIM or QMI mode. Successfully completing the firmware update should also resolve this issue if it occurs.

The exposed AT port can be used to send AT commands to the device using minicom to assist with troubleshooting.

root #emerge --ask net-dialup/minicom
root #minicom -D /dev/ttyUSB2

Within minicom, Ctrl+A then E will enable local echo (display commands as they're typed).

Type ATI to get some basic device info - if communications are successful a response similar to the following should be received:


Manufacturer: Sierra Wireless, Incorporated
Model: EM7430
Revision: SWI9X30C_02.26.01.00 r7120 CARMD-EV-FRMWR2 2017/09/15 18:38:46
MEID: 3############8
IMEI: 3#############4
FSN: LR8##########0


An AT command reference can be found here (login required).

Some commands (like AT!UDUSBCOMP) that are listed in the reference do not work. It is possible that these commands require proprietary drivers to modify the USB composition via AT commands. The recommended method for changing USB composition is listed above, anyway.

Kernel Config

A working example kernel config can be found here.

See also