T99W760 is designed based on Qualcomm SDX35(5G redcap) chip. There
are 3 serial ports to be enumerated: Modem, NMEA and Diag.

test evidence as below:
T:  Bus=03 Lev=01 Prnt=01 Port=03 Cnt=01 Dev#=  4 Spd=5000  MxCh= 0
D:  Ver= 3.20 Cls=ef(misc ) Sub=02 Prot=01 MxPS=64 #Cfgs=  1
P:  Vendor=0489 ProdID=e123 Rev=05.15
S:  Manufacturer=QCOM
S:  Product=SDXBAAGHA-IDP _SN:39A8D3E4
S:  SerialNumber=39a8d3e4
C:  #Ifs= 6 Cfg#= 1 Atr=a0 MxPwr=896mA
I:  If#= 0 Alt= 0 #EPs= 1 Cls=02(commc) Sub=0e Prot=00 Driver=cdc_mbim
E:  Ad=82(I) Atr=03(Int.) MxPS=  64 Ivl=32ms
I:  If#= 1 Alt= 1 #EPs= 2 Cls=0a(data ) Sub=00 Prot=02 Driver=cdc_mbim
E:  Ad=01(O) Atr=02(Bulk) MxPS=1024 Ivl=0ms
E:  Ad=81(I) Atr=02(Bulk) MxPS=1024 Ivl=0ms
I:  If#= 2 Alt= 0 #EPs= 3 Cls=ff(vend.) Sub=ff Prot=40 Driver=option
E:  Ad=02(O) Atr=02(Bulk) MxPS=1024 Ivl=0ms
E:  Ad=83(I) Atr=02(Bulk) MxPS=1024 Ivl=0ms
E:  Ad=84(I) Atr=03(Int.) MxPS=  10 Ivl=32ms
I:  If#= 3 Alt= 0 #EPs= 1 Cls=ff(vend.) Sub=ff Prot=ff Driver=(none)
E:  Ad=85(I) Atr=03(Int.) MxPS=  64 Ivl=32ms
I:  If#= 4 Alt= 0 #EPs= 3 Cls=ff(vend.) Sub=ff Prot=40 Driver=option
E:  Ad=03(O) Atr=02(Bulk) MxPS=1024 Ivl=0ms
E:  Ad=86(I) Atr=02(Bulk) MxPS=1024 Ivl=0ms
E:  Ad=87(I) Atr=03(Int.) MxPS=  10 Ivl=32ms
I:  If#= 5 Alt= 0 #EPs= 2 Cls=ff(vend.) Sub=ff Prot=30 Driver=option
E:  Ad=04(O) Atr=02(Bulk) MxPS=1024 Ivl=0ms
E:  Ad=88(I) Atr=02(Bulk) MxPS=1024 Ivl=0ms

0&1: MBIM, 2:Modem, 3:GNSS(non-serial port), 4: NMEA, 5:Diag

Signed-off-by: Slark Xiao <slark_xiao@163.com>
---
 drivers/usb/serial/option.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/usb/serial/option.c b/drivers/usb/serial/option.c
index e9400727ad36..d13226f9b811 100644
--- a/drivers/usb/serial/option.c
+++ b/drivers/usb/serial/option.c
@@ -2376,6 +2376,8 @@ static const struct usb_device_id option_ids[] = {
 	  .driver_info = RSVD(3) },
 	{ USB_DEVICE_INTERFACE_CLASS(0x0489, 0xe0f0, 0xff),			/* Foxconn T99W373 MBIM */
 	  .driver_info = RSVD(3) },
+	{ USB_DEVICE_INTERFACE_CLASS(0x0489, 0xe123, 0xff),			/* Foxconn T99W760 MBIM */
+	  .driver_info = RSVD(3) },
 	{ USB_DEVICE_INTERFACE_CLASS(0x0489, 0xe145, 0xff),			/* Foxconn T99W651 RNDIS */
 	  .driver_info = RSVD(5) | RSVD(6) },
 	{ USB_DEVICE_INTERFACE_CLASS(0x0489, 0xe15f, 0xff),                     /* Foxconn T99W709 */
-- 
2.25.1

On Tue, Nov 18, 2025 at 02:45:28PM +0800, Slark Xiao wrote:
> T99W760 is designed based on Qualcomm SDX35(5G redcap) chip. There
> are 3 serial ports to be enumerated: Modem, NMEA and Diag.
> 
> test evidence as below:
> T:  Bus=03 Lev=01 Prnt=01 Port=03 Cnt=01 Dev#=  4 Spd=5000  MxCh= 0
> D:  Ver= 3.20 Cls=ef(misc ) Sub=02 Prot=01 MxPS=64 #Cfgs=  1
> P:  Vendor=0489 ProdID=e123 Rev=05.15
> S:  Manufacturer=QCOM
> S:  Product=SDXBAAGHA-IDP _SN:39A8D3E4
> S:  SerialNumber=39a8d3e4
> C:  #Ifs= 6 Cfg#= 1 Atr=a0 MxPwr=896mA
> I:  If#= 0 Alt= 0 #EPs= 1 Cls=02(commc) Sub=0e Prot=00 Driver=cdc_mbim
> E:  Ad=82(I) Atr=03(Int.) MxPS=  64 Ivl=32ms
> I:  If#= 1 Alt= 1 #EPs= 2 Cls=0a(data ) Sub=00 Prot=02 Driver=cdc_mbim
> E:  Ad=01(O) Atr=02(Bulk) MxPS=1024 Ivl=0ms
> E:  Ad=81(I) Atr=02(Bulk) MxPS=1024 Ivl=0ms
> I:  If#= 2 Alt= 0 #EPs= 3 Cls=ff(vend.) Sub=ff Prot=40 Driver=option
> E:  Ad=02(O) Atr=02(Bulk) MxPS=1024 Ivl=0ms
> E:  Ad=83(I) Atr=02(Bulk) MxPS=1024 Ivl=0ms
> E:  Ad=84(I) Atr=03(Int.) MxPS=  10 Ivl=32ms
> I:  If#= 3 Alt= 0 #EPs= 1 Cls=ff(vend.) Sub=ff Prot=ff Driver=(none)
> E:  Ad=85(I) Atr=03(Int.) MxPS=  64 Ivl=32ms
> I:  If#= 4 Alt= 0 #EPs= 3 Cls=ff(vend.) Sub=ff Prot=40 Driver=option
> E:  Ad=03(O) Atr=02(Bulk) MxPS=1024 Ivl=0ms
> E:  Ad=86(I) Atr=02(Bulk) MxPS=1024 Ivl=0ms
> E:  Ad=87(I) Atr=03(Int.) MxPS=  10 Ivl=32ms
> I:  If#= 5 Alt= 0 #EPs= 2 Cls=ff(vend.) Sub=ff Prot=30 Driver=option
> E:  Ad=04(O) Atr=02(Bulk) MxPS=1024 Ivl=0ms
> E:  Ad=88(I) Atr=02(Bulk) MxPS=1024 Ivl=0ms
> 
> 0&1: MBIM, 2:Modem, 3:GNSS(non-serial port), 4: NMEA, 5:Diag
> 
> Signed-off-by: Slark Xiao <slark_xiao@163.com>

Applied, thanks.

Johan