I'm trying to get WiFi to work (device: Qualcomm Atheros Device 0042 (rev 31)) and I found the following line in the dmesg output.
Direct firmware load for ath10k/cal-pci-0000:02:00.0.bin failed with error -2
Now, I guess this driver is not included in my kernel (Linux 4.4.0-62-generic #83-Ubuntu SMP Wed Jan 18 14:10:15 UTC 2017 x86_64 x86_64 x86_64 GNU/Linux; Ubuntu Linux 16.04), so I have to clone The ath10k GitHub repo.
Which files do I have to copy to which directories i.o. to install the driver?
EDIT
After downloading the firmware package, installing it and rebooting the device is still not working.
When I try to connect I just get (in the dmesg output):
IPv6: ADDRCONF(NETDEV_UP): wlp2s0: link is not ready
The command dmesg | grep ath gives me
[    3.497692] ath10k_pci 0000:02:00.0: pci irq msi-x interrupts 8 irq_mode 0 reset_mode 0
[    3.743026] ath10k_pci 0000:02:00.0: Direct firmware load for ath10k/cal-pci-0000:02:00.0.bin failed with error -2
[    6.290044] ath10k_pci 0000:02:00.0: qca9377 hw1.1 (0x05020001, 0x003821ff sub 11ad:08a6) fw WLAN.TF.1.0-00267-1 fwapi 5 bdapi 2 htt-ver 3.1 wmi-op 4 htt-op 3 cal otp max-sta 32 raw 0 hwcrypto 1 features ignore-otp
[    6.290049] ath10k_pci 0000:02:00.0: debug 0 debugfs 1 tracing 1 dfs 0 testmode 0
[    6.291556] ath: EEPROM regdomain: 0x69
[    6.291559] ath: EEPROM indicates we should expect a direct regpair map
[    6.291562] ath: Country alpha2 being used: 00
[    6.291563] ath: Regpair used: 0x69
[    6.298835] ath10k_pci 0000:02:00.0 wlp2s0: renamed from wlan0