Success: Getting the rtl8822cs add-on BT/WiFi card for M5 working

It appears that every OS available specifically for the M5 does have the driver and overlay available for the wifi/bt module specifically for the M5 but for some reason isn’t setup to automatically load the driver itself). I thought the card was broken until I found out how to get it working. The WiFi is much better, bluetooth 4.0 works great, and I freed up a USB port when I no longer needed the dongle.

Here’s what you do…and this has worked on every image, including the “thanks to open source” images.

modify /boot/boot.ini by modifying the following line (typically line 96) and add the wifi_bt_rtl8822cs overlay driver like this:

 setenv overlays "i2c0 spi0 uart1 wifi_bt_rtl8822cs"

driver overlay can be manually loaded with command ‘modprobe 88x2cs’ but it’s better to also add to /etc/modules so it loads at every boot. (the modprobe command will immediately load the drivers and enable wifi without a reboot):

    vi /etc/modules-load.d/modules.conf
	    # append the following line to the end of modules.conf:

I can put together a one liner to do this automatically if anyone would like to just run “sudo [paste the one liner]>” but it’s so easy to just manually do it…like once every blue moon.

actually, this is only work for 4.9 bsp kernel image, and correct dtbo configuration is

setenv overlays "wifi_bt_rtl8822cs"

i2c0, spi0 and uart1 can’t be used when pins function configure to 8822cs.