[PATCH v2 0/1] usb: option.c: Fix Cinterion AHxx enumeration.

[PATCH v2 0/1] usb: option.c: Fix Cinterion AHxx enumeration.

[John Ernberg]

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

Added signoff and made corrections to the commit message after review by
Johan Hovold.

This resolves a race condition that may occur with Cinterion AH3 modem modules
if both the option and cdc_ether drivers are compiled as kernel modules.

Note:
Since I have no other AHxx modem modules to test with, I cannot guarantee that
this is the correct way to solve this issue globally.
This might break support for other AHxx modules.
Please consider this during the review of the patch.

Please explicitly keep me on CC as I did not register.

John Ernberg (1):
  usb: option.c: Fix Cinterion AHxx enumeration.

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

-- 
1.9.1

[PATCH v2 1/1] usb: option.c: Fix Cinterion AHxx enumeration.

[John Ernberg]

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

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

diff --git a/drivers/usb/serial/option.c b/drivers/usb/serial/option.c
index f228060..4e483f2 100644
--- a/drivers/usb/serial/option.c
+++ b/drivers/usb/serial/option.c
@@ -1679,7 +1679,7 @@ static const struct usb_device_id option_ids[] = {
 	{ 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) }, 
-- 
1.9.1

Re: [PATCH v2 1/1] usb: option.c: Fix Cinterion AHxx enumeration.

[Johan Hovold]

On Mon, Jan 25, 2016 at 12:27:17PM +0000, John Ernberg wrote:
> From: John Ernberg <john.ernberg@actia.se>
> 
> 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>

Now applied, thanks.

Johan