Merging device drivers to LK tree

[alexhoppus]

Hello!

I have several questions regarding how device drivers are merged into 
linux-kernel. First of all, I have found some document regarding 
submitting drivers to LK, but it  looks like pretty out-dated, 
https://kernelnewbies.org/UpstreamMerge/SubmittingDrivers
is this info still relevant? Or there is a new one?

Actually, I want to know more about the process. To start with this, I 
would like to ask an example question. Surfing through the kernel source 
I have found several ra-link usb wi-fi adapter drivers (rtl8188eu, 
rtl8192e, rtl8712 ...). Suppose one have datasheet that gives the 
possibility for writing a device driver for say rtlxxxxx based device. 
Can third-party person write & submit this driver to LK or this must be 
done explicitly by device vendor? What are the requirements from LK 
community side? Are there any license issues with this? (besides the 
author should publish code under GPL)