WiFi

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General information

To get wireless LAN working, most WiFi chips need a proprietary firmware blob. While it would be more secure to replace that with open source software in the long term, it isn't feasible right now, so we try to get it working with that closed source firmware.
A great place to start looking for information about many available WiFi chips is this kernel.org page. It often provides driver sources and the required firmware blobs as well. For a start if you want Internet working try the USB Internet guide.

Android-specific

Instead of mounting Android's firmware partition, we package the files ourselves (see the FAQ).

Requirements:

  • WiFi firmware files
  • Some firmwares need additional config files with calibration data, these can usually be found in the LineageOS or Google repositories.
  • Make sure all files get installed properly (look at the packaging of other devices with working wifi in our aports/device folder)

Path to firmware

Usually your Android kernel expects the firmware files to be in a folder like /system/vendor/firmware and you need to patch the kernel and change the path to /lib/firmware/postmarketos (see this patch. Sometimes there is no need to patch, but simply change a kernel option that defines this path.

Debugging

  • Find the wifi device name with ip link (wlan0 on most phones)
  • Try to start the wlan interface with ip link set wlan0 up.

When that worked, you're done with this section. Otherwise look in the following places for errors (such as missing firmware files):

  • dmesg
  • tail /var/log/firmwareload.log

If there is nothing helpful in these files, continue reading. The original OS may run a userspace application, that enables the wifi driver by doing essentially echo 1 > /dev/wcnss_wlan and echo sta > /sys/module/wlan/parameters/fwpath or execute similar commands. This was the case for wcnss-wlan (see aports/main/wcnss-wlan for how we packaged it).

Try to compare your sysfs and dmesg output with the one of a known working ROM after you have connected to a wireless network. Look for differences in /sys/module/wlan/.

Connecting to APs

postmarketOS currently configures the wpa_supplicant service to start on boot. This service will fail to start unless /etc/wpa_supplicant/wpa_supplicant.conf has been defined. This can be configured using the wpa_passphrase utility:

$ sudo wpa_passphrase YOUR_SSID > /etc/wpa_supplicant/wpa_supplicant.conf
<enter your passphrase and press RETURN>

Note: If you are connecting to a hidden wireless network, make sure to add line "scan_ssid=1" after the ssid line in your generated conf file

Next you'll need to set up the networking service by adding interfaces to /etc/network/interfaces. In some cases, the loopback device may need to precede the wlan interface:

auto lo 
iface lo inet loopback 
auto wlan0 
iface wlan0 inet dhcp

Finally, set the networking service to start on boot:

$ sudo rc-update add networking default

Note that on some systems (e.g. the RX51) you may have to configure wpa_supplicant to use the Linux kernel wireless extensions by editing /etc/conf.d/wpa_supplicant:

wpa_supplicant_args="-Dwext"

You will have to reboot, or manually restart the aforementioned services, before your device will connect to the access point.

Start WIFI manually

If you experience problems or just want to test wifi you can start wpa supplicant (using -Dwext or nl80211 driver) and the dhcp service:

sudo wpa_supplicant -u -Dnl80211 -B -c/etc/wpa_supplicant/wpa_supplicant.conf -iwlan0
sudo udhcpc -i wlan0

See also