I saw problems with Atheros on my Dell Inspiron, too.
These instructions helped me to reset the device without reboot:
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1730331/comments/40
I used modified script based on the one above (run as root):
set -e rmmod ath10k_pci 2> /dev/null || : rmmod ath10k_core 2> /dev/null || : rmmod ath 2> /dev/null || : { echo 1 > /sys/bus/pci/devices/0000:03:00.0/remove; } 2> /dev/null || : sleep 2 echo 1 > /sys/bus/pci/rescan
Try both scripts, one of them should work.
If still doesn't work, try to run original script, then do hibernate, if still doesn't work, run script again.
I finally was able to solve my problem by replacing Wi-Fi adapter. :) Here is my new Wi-Fi adapter:
[ 7.136347] iwlwifi 0000:03:00.0: Detected Intel(R) Dual Band Wireless AC 3160, REV=0x164
-- Askar Safin