The Atheros 1525/QCA6174 BT doesn't seem working properly on the
recent kernels, as it tries to load a wrong firmware
ar3k/AthrBT_0x00000200.dfu and it fails.

This seems to have been a problem for some time, and the known
workaround is to apply BTUSB_QCA_ROM quirk instead of BTUSB_ATH3012.

The device in question is:

T: Bus=01 Lev=01 Prnt=01 Port=09 Cnt=03 Dev#=  4 Spd=12   MxCh= 0
D: Ver= 1.10 Cls=e0(wlcon) Sub=01 Prot=01 MxPS=64 #Cfgs=  1
P: Vendor=0cf3 ProdID=3004 Rev= 0.01
C:* #Ifs= 2 Cfg#= 1 Atr=e0 MxPwr=100mA
I:* If#= 0 Alt= 0 #EPs= 3 Cls=e0(wlcon) Sub=01 Prot=01 Driver=btusb
E: Ad=81(I) Atr=03(Int.) MxPS=  16 Ivl=1ms
E: Ad=82(I) Atr=02(Bulk) MxPS=  64 Ivl=0ms
E: Ad=02(O) Atr=02(Bulk) MxPS=  64 Ivl=0ms
I:* If#= 1 Alt= 0 #EPs= 2 Cls=e0(wlcon) Sub=01 Prot=01 Driver=btusb
E: Ad=83(I) Atr=01(Isoc) MxPS=   0 Ivl=1ms
E: Ad=03(O) Atr=01(Isoc) MxPS=   0 Ivl=1ms
I: If#= 1 Alt= 1 #EPs= 2 Cls=e0(wlcon) Sub=01 Prot=01 Driver=btusb
E: Ad=83(I) Atr=01(Isoc) MxPS=   9 Ivl=1ms
E: Ad=03(O) Atr=01(Isoc) MxPS=   9 Ivl=1ms
I: If#= 1 Alt= 2 #EPs= 2 Cls=e0(wlcon) Sub=01 Prot=01 Driver=btusb
E: Ad=83(I) Atr=01(Isoc) MxPS=  17 Ivl=1ms
E: Ad=03(O) Atr=01(Isoc) MxPS=  17 Ivl=1ms
I: If#= 1 Alt= 3 #EPs= 2 Cls=e0(wlcon) Sub=01 Prot=01 Driver=btusb
E: Ad=83(I) Atr=01(Isoc) MxPS=  25 Ivl=1ms
E: Ad=03(O) Atr=01(Isoc) MxPS=  25 Ivl=1ms
I: If#= 1 Alt= 4 #EPs= 2 Cls=e0(wlcon) Sub=01 Prot=01 Driver=btusb
E: Ad=83(I) Atr=01(Isoc) MxPS=  33 Ivl=1ms
E: Ad=03(O) Atr=01(Isoc) MxPS=  33 Ivl=1ms
I: If#= 1 Alt= 5 #EPs= 2 Cls=e0(wlcon) Sub=01 Prot=01 Driver=btusb
E: Ad=83(I) Atr=01(Isoc) MxPS=  49 Ivl=1ms
E: Ad=03(O) Atr=01(Isoc) MxPS=  49 Ivl=1ms

Bugzilla: http://bugzilla.opensuse.org/show_bug.cgi?id=1082504Reported-by: Ivan Levshin <ivan.levshin@microfocus.com>
Tested-by: Ivan Levshin <ivan.levshin@microfocus.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>