From: Slark Xiao <slark_xiao@xxxxxxx> commit 3c841d54b63e4446383de3238399a3910e47d8e2 upstream. T99W651 is a RNDIS based modem device. There are 3 serial ports need to be enumerated: Diag, NMEA and AT. Test evidence as below: T: Bus=01 Lev=02 Prnt=02 Port=00 Cnt=01 Dev#= 6 Spd=480 MxCh= 0 D: Ver= 2.10 Cls=ef(misc ) Sub=02 Prot=01 MxPS=64 #Cfgs= 1 P: Vendor=0489 ProdID=e145 Rev=05.15 S: Manufacturer=QCOM S: Product=SDXPINN-IDP _SN:93B562B2 S: SerialNumber=82e6fe26 C: #Ifs= 7 Cfg#= 1 Atr=a0 MxPwr=500mA I: If#=0x0 Alt= 0 #EPs= 1 Cls=ef(misc ) Sub=04 Prot=01 Driver=rndis_host I: If#=0x1 Alt= 0 #EPs= 2 Cls=0a(data ) Sub=00 Prot=00 Driver=rndis_host I: If#=0x2 Alt= 0 #EPs= 3 Cls=ff(vend.) Sub=ff Prot=40 Driver=option I: If#=0x3 Alt= 0 #EPs= 3 Cls=ff(vend.) Sub=ff Prot=40 Driver=option I: If#=0x4 Alt= 0 #EPs= 2 Cls=ff(vend.) Sub=ff Prot=30 Driver=option I: If#=0x5 Alt= 0 #EPs= 1 Cls=ff(vend.) Sub=ff Prot=70 Driver=(none) I: If#=0x6 Alt= 0 #EPs= 2 Cls=ff(vend.) Sub=42 Prot=01 Driver=(none) 0&1: RNDIS, 2:AT, 3:NMEA, 4:DIAG, 5:QDSS, 6:ADB QDSS is not a serial port. Signed-off-by: Slark Xiao <slark_xiao@xxxxxxx> Cc: stable@xxxxxxxxxxxxxxx Signed-off-by: Johan Hovold <johan@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/usb/serial/option.c | 2 ++ 1 file changed, 2 insertions(+) --- a/drivers/usb/serial/option.c +++ b/drivers/usb/serial/option.c @@ -2294,6 +2294,8 @@ static const struct usb_device_id option .driver_info = RSVD(3) }, { USB_DEVICE_INTERFACE_CLASS(0x0489, 0xe0f0, 0xff), /* Foxconn T99W373 MBIM */ .driver_info = RSVD(3) }, + { USB_DEVICE_INTERFACE_CLASS(0x0489, 0xe145, 0xff), /* Foxconn T99W651 RNDIS */ + .driver_info = RSVD(5) | RSVD(6) }, { USB_DEVICE(0x1508, 0x1001), /* Fibocom NL668 (IOT version) */ .driver_info = RSVD(4) | RSVD(5) | RSVD(6) }, { USB_DEVICE(0x1782, 0x4d10) }, /* Fibocom L610 (AT mode) */ Patches currently in stable-queue which might be from slark_xiao@xxxxxxx are queue-4.19/usb-serial-option-add-support-for-foxconn-t99w651.patch