Christian Lamparter wrote:

So, if we call usb_reset_device there and the driver is unbound
and later rebound. the next ath9k_htc .probe will start again and
again and again not knowing that it is already initialized 
(and we have a loop).

The HW/FW is buggy and this workaround is required:
http://marc.info/?l=linux-usb&m=127960864905646&w=2

Sujith