[LEDE-DEV] rtl8189fs/rtl8189es/rtl8723bs cfg80211_rtw_add_virtual_intf broken

[Hauke Mehrtens]

Hi,

I tried to make the crappy Realtek rtl8189fs/rtl8189es/rtl8723bs wifi
drivers work in OpenWrt, but gave up for now. I just want to write my
current observations.

When OpenWrt finds a nl80211 compatible wifi device it deletes all the
existing virtual interfaces and then creates the configured interfaces
again, this works with all the supported cfg80211 based wifi drivers in
OpenWrt and is ok in my opinion. See:
https://git.openwrt.org/?p=openwrt/openwrt.git;a=blob;f=package/kernel/mac80211/files/lib/netifd/wireless/mac80211.sh;h=bf9d52ae4203c294e25487f1678cfcd25e7a1dce;hb=HEAD#l465

This does not work with the crappy Realtek drivers. Deletion of
interfaces is supported by the crappy Realtek driver, but it can only
create monitor interfaces again and no managed or ap interfaces, which
makes it pretty useless.

To support these drivers the cfg80211_rtw_add_virtual_intf() functions
has to support adding an interface other than the monitor interface.

rtl8723bs:
https://elixir.bootlin.com/linux/latest/source/drivers/staging/rtl8723bs/os_dep/ioctl_cfg80211.c#L2713

rtl8189es:
https://github.com/jwrdegoede/rtl8189ES_linux/blob/master/os_dep/linux/ioctl_cfg80211.c#L3994

rtl8189fs:
https://github.com/jwrdegoede/rtl8189ES_linux/blob/rtl8189fs/os_dep/linux/ioctl_cfg80211.c#L4040

I added these drivers to OpenWrt, but will not merge this into master as
long as it does not work at all in OpenWrt, see my development branch here:
https://git.openwrt.org/?p=openwrt/staging/hauke.git;a=shortlog;h=refs/heads/rtl8189

Hauke