LWB5+ Dongle i.MX 8M Plus Yocto Integration

This tutorial will show you how to integrate the LWB5+ Dongle on an i.MX 8M Plus Yocto platform. To watch video tutorial, click here.

Required Tools

  • LWB5+ Dongle (Part No. 450-00137)
  • i.MX 8M Plus EVK (Part No. 8MPLUSLPD4-EVK)
  • Linux PC with a Yocto Build Environment. As a prerequisite for this tutorial, we are going to assume that you know how to setup a Yocto build environment. This is covered very well in NXP’s documentation ( i.e. see i.MX_Yocto_Project_User’s_Guide.pdf, Rev. L5.4.70_2.3.0 — 31 December 2020 for details on how to install the required host packages and the repo utility, and how to setup git); so we will not cover it here. We will focus on how to add Laird Connectivity’s external layer into a Yocto build.

Setup

We will flash our image into a micro SD card. If you prefer, you can use the onboard eMMC, but for this tutorial. we will boot from a micro SD card. The LWB5+ Dongle will plug into J7. Power will be applied via J5, and J23 will be used to connect to a serial terminal (115200, N, 8, 1). If the build works, the drivers will automatically load on power up. We will then connect to an AP and do a ping to demonstrate that Wi-Fi works. For Bluetooth, we will do a scan to show that the module can detect devices that are discoverable or advertising.

  1. Download the i.MX Yocto Project Community BSP recipe layers

    Reminder: Prior to proceeding, make sure the required host packages and repo utility are installed. Git must also be configured properly. Refer to i.MX_Yocto_Project_User’s_Guide.pdf, Rev. L5.4.70_2.3.0 — 31 December 2020 for details.

    mkdir ~/projects/imx8mp
cd ~/projects/imx8mp
repo init -u https://source.codeaurora.org/external/imx/imx-manifest -b imx-linux-kirkstone -m imx-5.15.32-2.0.0.xml && repo sync

  2. Setup build configuration

    DISTRO=fsl-imx-wayland MACHINE=imx8mpevk source imx-setup-release.sh -b build-imx8p-wayland

  3. Modify the ~/projects/imx8mp/build-imx8p-wayland/conf/bblayers.conf file. Add the line below to the file.

    BBLAYERS += "${BSPDIR}/sources/meta-summit-radio/meta-summit-radio"

    Note: for Yocto projects 3.3 (Hardknott) and earlier the line you add would be

    BBLAYERS += "${BSPDIR}/sources/meta-summit-radio/meta-summit-radio-pre-3.4"

  4. Modify the ~/projects/imx8mp/build-imx8p-wayland/conf/local.conf file. Add the lines below to the file.

    PREFERRED_PROVIDER_wpa-supplicant = "sterling-supplicant" 
PREFERRED_PROVIDER_wpa-supplicant-cli = "sterling-supplicant" 
PREFERRED_PROVIDER_wpa-supplicant-passphrase = "sterling-supplicant" 
   
BBMASK += " \ 
    meta-summit-radio/meta-summit-radio/recipes-packages/openssl \ 
    meta-summit-radio/meta-summit-radio/recipes-packages/.*/.*openssl10.* \ 
    "
   
PREFERRED_RPROVIDER_wireless-regdb-static = "wireless-regdb" 
LWB_REGDOMAIN = "US"

    Note: for Yocto projects 3.3 (Hardknott) and earlier you would add:

     PREFERRED_PROVIDER_wpa-supplicant = "sterling-supplicant" 
PREFERRED_PROVIDER_wpa-supplicant-cli = "sterling-supplicant" 
PREFERRED_PROVIDER_wpa-supplicant-passphrase = "sterling-supplicant" 
   
BBMASK += " \ 
    meta-summit-radio/meta-summit-radio-pre-3.4/recipes-packages/openssl \ 
    meta-summit-radio/meta-summit-radio-pre-3.4/recipes-packages/.*/.*openssl10.* \ 
    "
   
PREFERRED_RPROVIDER_wireless-regdb-static = "wireless-regdb" 
LWB_REGDOMAIN = "US"

  5. Clone the meta-summit-radio layer into ~/projects/imx8mp/sources directory

    cd ~/projects/imx8mp/sources
git clone https://github.com/LairdCP/meta-summit-radio

  6. Edit the ~/projects/imx8mp/sources/meta-summit-radio/meta-summit-radio/recipes-packages/images/sample-image-cp-lwb5plus.bb recipe by replacing lwb5plus-sdio-div-firmware with lwb5plus-usb-sa-firmware and adding laird-networkmanager. Then save it as mylwb5p.bb. A snippet of the saved file is shown below.

    IMAGE_INSTALL += "\ 
iproute2 \ 
rng-tools \ 
ca-certificates \ 
tzdata \ 
alsa-utils \ 
htop \ 
ethtool \ 
iperf3 \ 
tcpdump \ 
iw \ 
kernel-module-lwb5p-backports-summit \ 
lwb5plus-usb-sa-firmware \ 
sterling-supplicant-lwb \ 
summit-networkmanager-st60 \ 
"

  7. Next go to the build directory and run menuconfig to configure the Kernel.

    cd ../build-imx8p-wayland 
bitbake -c menuconfig virtual/kernel

    • Disable Wireless LAN drivers. Navigate to Device Drivers -> Network device support and disable Wireless LAN .

    • Disable Bluetooth subsystem support and Wireless. Navigate to Networking support and disable Bluetooth subsystem support and Wireless.

    • Save your changes and exit menuconfig

  8. Build the image

     bitbake mylwb5p

  9. Flash image into SD card. Note: for this particular tutorial the SD card is on /dev/mmcblk0. It may be different for your setup; so make sure you change the command below per your setup.

     bzip2 -dc ~/projects/imx8mp/build-imx8p-wayland/tmp/deploy/images/imx8mpevk/mylwb5p-imx8mpevk.wic.bz2 | sudo dd bs=512K iflag=fullblock oflag=direct status=progress conv=fsync of=/dev/mmcblk0
    
 sync

  10. Connect EVK to Serial Terminal via J23 (115200, N, 8, 1). Note for this tutorial we use /dev/ttyUSB2 port to connect. Your Linux PC might use a different port. Boot device and login as root.

  11. Test Wi-Fi. Create a connection profile with nmcli. Then connect to the AP and ping a website.

     nmcli con add con-name "YourProfile" ifname wlan0 type wifi ssid "YourAP" wifi-sec.key-mgmt wpa-psk wifi-sec.psk "YourPassword" 
 nmcli c u "YourProfile" 
 ping www.google.com

  12. Test Bluetooth. Launch bluetoothctl. Then on the bluetoothctl prompt, type power on and then scan on.

References