I bought these Arduino Nano clones from Aliexpress and it turns out they might not work on the Rpi. This post seems to have an answer. I wanted to bookmark the solution but I am sharing it here instead.
This device is:
There is a patch in -mm kernel tree, so I guess it goes to 2.6.24 soon. But if you don’t want to wait, here is a solution using the new ch341 usb serial driver:
Then extract the files and comment out lines 301 and 303 of ch341.c file and also line 35 of the tty_ioctl.c file.
Finally run ins.sh to compile and load the modules and use minicom, cu, cutecom or what you prefer to connect to the /dev/ttyUSB0 device.
I’ve seen some people trying to use pl2303 driver with a little patch to use this device. It doesn’t work.