WiFi DELL XPS 13 9360 keeps disconnecting with QCA6174 802.11ac Wireless Network Adapter
Solution 1:
I would disable wifi power management with
sudo sed -i 's/wifi.powersave = 3/wifi.powersave = 2/' /etc/NetworkManager/conf.d/default-wifi-powersave-on.confChange the encryption on the wireless router to WPA2 only with no WEP, TKIP or plain WPA, depending on the router it may be called WPA2-PSK, WPA2-AES or WPA2 Personal.
Reinstall the linux-firmware package
sudo apt-get install --reinstall linux-firmwareReboot
Solution 2:
I think I fixed it. The problem probably originated from my router settings. When I changed from 802.11n+g+b to 802.11n+g the connection seems stable. Although over time I changed quite a lot of setting in Ubuntu and my router, this seemed to do the trick.
Edit 1/7/17: Later I found another crucial option which I had to uncheck in order to get it to work. In my Fritzbox router it is called:
Wireless LAN coexistence enabled
In heavily used wireless environments the available channel width is divided among the participants in the best way possible.
I think this option sometimes changes the bandwidth of the signal. When this happens the connection is lost between my laptop and the router. In the /var/log/syslog file I also saw something like: bandwidth changed, connection lost, if I recall correctly.
Solution 3:
you can try removing and re-adding kernel module of your wifi driver
lsmod |grep wifi
in my machine I got the following:
iwlwifi 200704 1 iwlmvm
cfg80211 565248 3 iwlwifi,mac80211,iwlmvm
then:
sudo modprobe -r iwlwifi && sudo modprobe iwlwifi
Solution 4:
I had the same problem with this wifi card on Debian. Updating settings on router wasn't an option. What helped was to update binary firmware from here: https://github.com/kvalo/ath10k-firmware/tree/master/QCA6174/hw3.0/4.4.1
Just download last version and replace file firmware-6.bin located at /lib/firmware/ath10k/QCA6174/hw3.0/.
Then reload affected kernel modules:
modprobe -r ath10k_pci ath10k_core
modprobe ath10k_pci
modprobe ath10k_core