Configure WLAN for RaspberryPI3 using image created with Yocto

Question

I have some trouble trying to configure my wlan in my new RaspberryPi3 maybe you can help me.

I created my own image for the RaspberryPI3 using the Yocto Jethro (rpi-basic-image) and Ubuntu 14.04. It worked and my RaspberryPI3 booted. Then I tried to configure my wlan connection. I didn’t touch the file /etc/network/interfaces since it looks good to me :

iface wlan0 inet dhcp
  wireless_mode managed
  wireless_essid any
  wpa-driver wext
  wpa-conf /etc/wpa_supplicant.conf

The file /etc/wpa_supplicant.conf didn’t exit and I created :

network={
  ssid="wlan-name"
  psk="keyHex"
  proto=RSN
  key_mgmt=WPA-PSK
  pairwise=CCMP
  auth_alg=OPEN
}

Then I tried ifup wlan0 and I got the flag:

ifconfig: SIOCGIFFLAGS: No such device

Do you know what I did wrong or what is missing? Thank you in advanced

Answer 1

wlan0 is not detected, I had the same issue. I think you didn't load the kernel modules to use the in-built wifi. If you look into the configuration file for the rpi3 in yocto, you have the recipe linux-firmware-brcm43430 which should be compiled and added into the rootfs.

The kernel modules are .ko files. Find them in your yocto compiled folder. <yocto_path>/build/tmp/work/ and add them to your filesystem. Load the module, check you have wlan0 doing ifconfig -a.

Answer 2

The Blog blog has explained it nicely. It worked for me
Here is the instruction as explained in the blog:
Add following line to build/local.conf

DISTRO_FEATURES_append = " bluez5 bluetooth wifi"
IMAGE_INSTALL_append = " linux-firmware-bcm43430 bluez5 i2c-tools python-smbus bridge-utils hostapd dhcp-server iptables wpa-supplicant"

Add following lines to bblayers.conf

${BSPDIR}/sources/meta-openembedded/meta-python \
${BSPDIR}/sources/meta-openembedded/meta-networking \

cd to home directory for Yocto

cd ~/yocto/

Source the build environment script

source sources/poky/oe-init-build-env rpi-build

Build image with new recipes and features

bitbake [image-name]

Copy the newly built image in SD card Boot Raspberry Pi 3 with newly built image. Edit wpa_supplicant file

vi /etc/wpa_supplicant.conf

Change to content to following

ctrl_interface=/var/run/wpa_supplicant
ctrl_interface_group=0
update_config=1
network={
    ssid="<SSID_NAME>"
    psk="<PASSWORD>"
    proto=RSN
    key_mgmt=WPA-PSK
    pairwise=CCMP
    auth_alg=OPEN
}

Restart Rpi3

reboot

Log in to Raspberry Pi 3 and configure Wi-Fi

ifup wlan0