Ignoring interfaces with additional descriptors is not a reliable
method for locating the correct interface on Gobi devices. There
is at least one device where this method fails:
https://bbs.archlinux.org/viewtopic.php?id=143506
The result is that the AT command port (interface #2) is hidden
from qcserial, preventing traditional serial modem usage:
[ 15.562552] qmi_wwan 4-1.6:1.0: cdc-wdm0: USB WDM device
[ 15.562691] qmi_wwan 4-1.6:1.0: wwan0: register 'qmi_wwan' at usb-0000:00:1d.0-1.6, Qualcomm Gobi wwan/QMI device, 1e:df:3c:3a:4e:3b
[ 15.563383] qmi_wwan: probe of 4-1.6:1.1 failed with error -22
[ 15.564189] qmi_wwan 4-1.6:1.2: cdc-wdm1: USB WDM device
[ 15.564302] qmi_wwan 4-1.6:1.2: wwan1: register 'qmi_wwan' at usb-0000:00:1d.0-1.6, Qualcomm Gobi wwan/QMI device, 1e:df:3c:3a:4e:3b
[ 15.564328] qmi_wwan: probe of 4-1.6:1.3 failed with error -22
[ 15.569376] qcserial 4-1.6:1.1: Qualcomm USB modem converter detected
[ 15.569440] usb 4-1.6: Qualcomm USB modem converter now attached to ttyUSB0
[ 15.570372] qcserial 4-1.6:1.3: Qualcomm USB modem converter detected
[ 15.570430] usb 4-1.6: Qualcomm USB modem converter now attached to ttyUSB1
Use static interface numbers taken from the interface map in
qcserial for all Gobi devices instead:
Gobi 1K USB layout:
0: serial port (doesn't respond)
1: serial port (doesn't respond)
2: AT-capable modem port
3: QMI/net
Gobi 2K+ USB layout:
0: QMI/net
1: DM/DIAG (use libqcdm from ModemManager for communication)
2: AT-capable modem port
3: NMEA
This should be more reliable over all, and will also prevent the
noisy "probe failed" messages. The whitelisting logic is expected
to be replaced by direct interface number matching in 3.6.
Reported-by: Heinrich Siebmanns (Harvey) <H.Siebmanns@t-online.de>
Cc: <stable@vger.kernel.org> # v3.4: 0000188 USB: qmi_wwan: Make forced int 4 whitelist generic
Cc: <stable@vger.kernel.org> # v3.4: f7142e6 USB: qmi_wwan: Add ZTE (Vodafone) K3520-Z
Cc: <stable@vger.kernel.org> # v3.4
Signed-off-by: Bjørn Mork <bjorn@mork.no>
Signed-off-by: David S. Miller <davem@davemloft.net>
b9f90eb274