Could not connect to wpa_supplicant: wlan0 - re-trying

[Bartlomiej Grzeskowiak]

I work on embedded device and I am configuring the WLAN module
(QCA6174 - ath10k driver) with wpa_supplicant.

I load the driver modules (backports-20151120):

insmod /lib/modules/3.10.65-b2196-h301/wlan/compat.ko;
insmod lib/modules/3.10.65-b2196-h301/wlan/cfg80211.ko;
insmod /lib/modules/3.10.65-b2196-h301/wlan/mac80211.ko;
insmod /lib/modules/3.10.65-b2196-h301/wlan/ath.ko;
insmod /lib/modules/3.10.65-b2196-h301/wlan/ath10k_core.ko skip_otp=y;
insmod /lib/modules/3.10.65-b2196-h301/wlan/ath10k_pci.ko

I start the wpa_supplicant (default wpa_supplicant.conf):

wpa_supplicant -dd -Dwext -i wlan0 -c /etc/wpa_supplicant/wpa_supplicant.conf -B
[  182.257304] IPv6: ADDRCONF(NETDEV_CHANGE): wlan0: link becomes ready

everything seems to work fine. I see the wlan0 interface,I can scan
with iwlist, /var/run/wpa_supplicant/wlan0 exist.

But I can not use wpa_cli interface:

 #wpa_cli
 wpa_cli v2.4
 Copyright (c) 2004-2015, Jouni Malinen <j at w1.fi> and contributors
 Selected interface 'wlan0'

Interactive mode

Could not connect to wpa_supplicant: wlan0 - re-trying

Do you have any hints how can I track down the problem ?