I installed openwrt onto the raspberry pi 3B+ only to understand that the broadcom wifi of the raspberry pi isn’t well supported. Could you please add this as a big fat disclaimer to the Raspberry download?
Instead I found an old Asus N13, probably equal to RTL8192 which provides 2.4 GHz 802.11n. Exactly what I need.
The USB device shows up as
Bus 001 Device 008: ID 0b05:17ab Realtek 802.11n WLAN Adapter
but the wifi device is missing. So I believe the driver isn’t loaded.
I found several hints to some kernel modules like rt8000 but cannot find these drivers for OpenWRT.
Au contraire, exactly what you don’t want.
(the general topic of USB WLAN and AP mode has been discussed numerous times, so refer to those).
0b05:17ab suggests rtl8192cu, which is in a bit of a special situation, as it’s ‘supported’ by two different drivers, kmod-rtl8192cuXORrtl8xxxu(install one or the other, including rtl8192cu-firmware, but NOT both at the same time). Neither driver will do AP mode in an acceptable fashion (if at all), the firmware is not audited for AP mode (if it works, it would be purely accidental), nor is the hardware designed for either AP mode nor continuous operations (overheating is likely to be a topic). Driver support for Realtek WLAN, particularly Realtek USB WLAN, is not on par with the alternatives, some drivers may work well, others won’t - none are tested for AP mode.
That aside, the RPi ecosystem in general is not good at doing WLAN (regardless of ‘how’) - and anything below the RPi4 also troubled by their USB2 system bus, neither for WLAN nor wired routing, it’s not a good choice.
It would be more sensible to offload the wireless functionality to a more purpose built, more contemporary (802.11ac/ wifi5 or better) plastic wifi router running OpenWrt, than trying to shoehorn WLAN on a RPi, much faster, way more reliable, probably even cheaper - and while you’re at it, this wifi router could also -better- replace the wired functionality of the RPi3… New options start in the 15-30 EUR range, and there are always your local used markets to find decent gear cheaply.
Wow. Thanks for the clear words. Could you please add this as a disclaimer to the raspberry pi download, to save users and those people like you helping the hassle of discussing this topic over and over?
that list would be veeery long, and include most Realtek based wifi devices....
problem is, you usually don't know what you'll be getting when you buy an USB wifi adapter.
you discover it once you've unpacked it.
It does give me headaches, especially as there are sometimes things that do depend on other parts of the base kernel (particularly the ipq807x/ ipq60xx/ ipq50xx and ath11k do depend on remoteproc and similar things).
But apart from this, the wireless backports projects is rather long established (although I'm unsure how active its use is outside of OpenWrt these days) - and in general relatively adept to work on different kernel versions. At the same time it is difficult to keep all targets on the same base kernel, and during development they often aren't for many months (even though the release targets a single kernel for everything, for obvious maintenance reasons). And in many cases, very recent wireless code is needed anyways, so it would be a case of heaps of driver specific backports or backporting all mac80211+driver code together (and yes, I realize that m76 is the odd one out here, as that's closer to linux-next).
It is kind of a mess, and in an ideal world, where SOC/ target specific patches wouldn't be needed (respectively exclusively short lived and strict backports from -next or -next-next), things could be a lot neater, sadly reality tells a different story. The more recent targets tend to be a bit better, in the sense that the target specific patch stack is largely -next-next(-next) like backports and will decrease over time, but even there we do see some aspects that are really hard to mainline and will stand out like a sore thumb for longer.
