LG Fx0 (lg-madai)
LG Fx0 running Xfce4
|Original software||Firefox OS 2.0|
|Chipset||Qualcomm Snapdragon 400 (MSM8926)|
|CPU||4x ARM Cortex-A7|
|Non-Android based device||✔|
Users owning this device
How to enter flash mode
- Hold + : LG Recovery (only factory reset)
adb reboot recoveryon adb shell: AOSP recovery
- Hold while connecting to the USB: LG download mode/fastboot (if laf partition is zeroed)
- Source: 
To use fastboot you need to remove the laf on the Firefox OS. Given that there is no kdz or tot file for this device available, it does not make sense to keep laf for flashing.
# Backup your LAF partition - on adb shell su dd if=/dev/block/platform/msm_sdcc.1/by-name/laf of=/sdcard/laf.img dd if=/dev/zero of=/dev/block/platform/msm_sdcc.1/by-name/laf # On the host adb pull /sdcard/laf.img
There are three partitions: system (1 GiB ext4, mmcblk0p35), userdata (4 GiB ext4, mmcblk0p37), and sdcard (~8.5 GiB vfat, mmcblk0p38). Do not ZERO out the userdata partition, as this partition contains some firmware files (audio and Wi-Fi) customized to the device.
- UART: According to service manual UART is provided as a part of JTAG connector, unpopulated by default and only accessible after opening the case. The Pin 14 (lower right, bigger pad than others) is MSM_UART_TX, which needs to be hooked up to the RX of the UART adapter.
- Wi-Fi: Qualcomm WCNSS. Note that the LG source code archive lacks the prima driver, which is used in Firefox OS. According to
dmesgin Firefox OS, it is version v184.108.40.206. Porting the prima driver from LineageOS kernel makes Wi-Fi work, but it seems that NetworkManager seems not like this configuration.
- Display: no backlight adjustment yet, also had to change the visual to RGB565 to get a working Xfce4.
- Given the sorry quality and lower version of stock LG kernel, maybe mainlining could be worth?
- Kernel source (mirrored from LG OSS Center when it was alive)