>> >> This would be when running on configuration #1: >> >> T: Bus=04 Lev=03 Prnt=04 Port=02 Cnt=01 Dev#= 7 Spd=5000 MxCh= 0 >> D: Ver= 3.10 Cls=ef(misc ) Sub=02 Prot=01 MxPS= 9 #Cfgs= 2 >> P: Vendor=413c ProdID=81d7 Rev=03.18 >> S: Manufacturer=DELL >> S: Product=DW5821e Snapdragon X20 LTE >> S: SerialNumber=0123456789ABCDEF >> C: #Ifs= 5 Cfg#= 1 Atr=a0 MxPwr=896mA >> I: If#=0x0 Alt= 0 #EPs= 2 Cls=ff(vend.) Sub=ff Prot=ff Driver=qcserial >> I: If#=0x1 Alt= 0 #EPs= 3 Cls=ff(vend.) Sub=ff Prot=ff Driver=qmi_wwan >> I: If#=0x2 Alt= 0 #EPs= 3 Cls=ff(vend.) Sub=00 Prot=00 Driver=qcserial >> I: If#=0x3 Alt= 0 #EPs= 3 Cls=ff(vend.) Sub=00 Prot=00 Driver=qcserial >> I: If#=0x4 Alt= 0 #EPs= 3 Cls=ff(vend.) Sub=00 Prot=00 Driver=(none) > > So this doesn't really match the Sierra layout in qcserial, where the > QMI interface is documented as interface 8 (but perhaps we have other > examples of that already). > > Do you know what these serial ports are used for? > You know what, I kind of missed that. This Dell device is not based on Sierra Wireless, so using the Sierra layout is not a good idea. Let me try to confirm with the manufacturer the purpose of each interface. >> This would be when running on configuration #2: >> >> T: Bus=04 Lev=03 Prnt=04 Port=02 Cnt=01 Dev#= 6 Spd=5000 MxCh= 0 >> D: Ver= 3.10 Cls=ef(misc ) Sub=02 Prot=01 MxPS= 9 #Cfgs= 2 >> P: Vendor=413c ProdID=81d7 Rev=03.18 >> S: Manufacturer=DELL >> S: Product=DW5821e Snapdragon X20 LTE >> S: SerialNumber=0123456789ABCDEF >> C: #Ifs= 3 Cfg#= 2 Atr=a0 MxPwr=896mA >> I: If#=0x0 Alt= 0 #EPs= 1 Cls=02(commc) Sub=0e Prot=00 Driver=cdc_mbim >> I: If#=0x1 Alt= 1 #EPs= 2 Cls=0a(data ) Sub=00 Prot=02 Driver=cdc_mbim >> I: If#=0x2 Alt= 0 #EPs= 1 Cls=ff(vend.) Sub=ff Prot=ff Driver=qcserial > > And here you happen to bind interface 2, but is that intentional? What > is that port used for? > Same here; looks like interface was bound to qcserial by chance, because that is what the sierra layout would have done in the QMI capable configuration. Again, let me try to confirm what that other interface may be for. > Just based on the above, perhaps using option and matching on the vendor > class, while blacklisting interface 1 would be more appropriate? > Being a Qualcomm based chipset, I believe qcserial would be more appropriate. I'll send an updated patch, including usb-devices output, once I have an explanation for all questions. -- Aleksander https://aleksander.es -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html