Foxconn SDX55 T77W175 device is working in PCIe mode normally. You can find the PCIe support in drivers/bus/mhi/pci_generic.c file. But in some scenario, we need to capture the memory dump once it crashed. So a diag port under USB driver is needed. Only interface 0 is used: jbd@jbd-ThinkPad-P1-Gen-4:~$ lsusb | grep 05c6 Bus 003 Device 010: ID 05c6:901d Qualcomm, Inc. Generic Mobile Broadband Adapter jbd@jbd-ThinkPad-P1-Gen-4:~$ lsusb -t | grep "Dev 10" |__ Port 7: Dev 10, If 0, Class=Vendor Specific Class, Driver=option, 480M Signed-off-by: Slark Xiao <slark_xiao@xxxxxxx> --- drivers/usb/serial/option.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/usb/serial/option.c b/drivers/usb/serial/option.c index 039450069ca4..c275f489c1cc 100644 --- a/drivers/usb/serial/option.c +++ b/drivers/usb/serial/option.c @@ -2068,6 +2068,7 @@ static const struct usb_device_id option_ids[] = { .driver_info = RSVD(0) | RSVD(1) | RSVD(6) }, { USB_DEVICE(0x0489, 0xe0b5), /* Foxconn T77W968 ESIM */ .driver_info = RSVD(0) | RSVD(1) | RSVD(6) }, + { USB_DEVICE(QUALCOMM_VENDOR_ID, 0x901d) }, /* Foxconn T77W175 PCIE+USB mode*/ { USB_DEVICE(0x1508, 0x1001), /* Fibocom NL668 (IOT version) */ .driver_info = RSVD(4) | RSVD(5) | RSVD(6) }, { USB_DEVICE(0x2cb7, 0x0104), /* Fibocom NL678 series */ -- 2.25.1