[PATCH 4.4 067/117] USB: option: fix Cinterion AHxx enumeration

Greg Kroah-Hartman
2016-02-15T00:33:29Z

From: John Ernberg <john.ernberg@actia.se>

commit 4152b387da81617c80cb2946b2d56e3958906b3e upstream.

In certain kernel configurations where the cdc_ether and option drivers
are compiled as modules there can occur a race condition in enumeration.
This causes the option driver to enumerate the ethernet(wwan) interface
as usb-serial interfaces.

usb-devices output for the modem:
T: Bus=01 Lev=01 Prnt=01 Port=00 Cnt=01 Dev#= 5 Spd=480 MxCh= 0
D: Ver= 2.00 Cls=ef(misc ) Sub=02 Prot=01 MxPS=64 #Cfgs= 1
P: Vendor=1e2d ProdID=0055 Rev=00.00
S: Manufacturer=Cinterion
S: Product=AHx
C: #Ifs= 6 Cfg#= 1 Atr=e0 MxPwr=10mA
I: If#= 0 Alt= 0 #EPs= 2 Cls=ff(vend.) Sub=ff Prot=ff Driver=option
I: If#= 1 Alt= 0 #EPs= 2 Cls=ff(vend.) Sub=ff Prot=ff Driver=option
I: If#= 2 Alt= 0 #EPs= 2 Cls=ff(vend.) Sub=ff Prot=ff Driver=option
I: If#= 3 Alt= 0 #EPs= 3 Cls=ff(vend.) Sub=ff Prot=ff Driver=option
I: If#= 4 Alt= 0 #EPs= 1 Cls=02(commc) Sub=06 Prot=00 Driver=cdc_ether
I: If#= 5 Alt= 1 #EPs= 2 Cls=0a(data ) Sub=00 Prot=00 Driver=cdc_ether

Signed-off-by: John Ernberg <john.ernberg@actia.se>
Fixes: 1941138e1c02 ("USB: added support for Cinterion's products...")
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/usb/serial/option.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/usb/serial/option.c
+++ b/drivers/usb/serial/option.c
@@ -1695,7 +1695,7 @@ static const struct usb_device_id option
{ USB_DEVICE(CINTERION_VENDOR_ID, CINTERION_PRODUCT_EU3_P) },
{ USB_DEVICE(CINTERION_VENDOR_ID, CINTERION_PRODUCT_PH8),
.driver_info = (kernel_ulong_t)&net_intf4_blacklist },
- { USB_DEVICE(CINTERION_VENDOR_ID, CINTERION_PRODUCT_AHXX) },
+ { USB_DEVICE_INTERFACE_CLASS(CINTERION_VENDOR_ID, CINTERION_PRODUCT_AHXX, 0xff) },
{ USB_DEVICE(CINTERION_VENDOR_ID, CINTERION_PRODUCT_PLXX),
.driver_info = (kernel_ulong_t)&net_intf4_blacklist },
{ USB_DEVICE(CINTERION_VENDOR_ID, CINTERION_PRODUCT_HC28_MDM) },