[PATCH v3] USB: serial: option: add Compal EXM-G1x support
From: Ian Lin
Date: Mon Aug 31 2026 - 04:50:19 EST
The Compal EXM-G1x is a Qualcomm SDX12-based LTE modem. Add support for
its vendor-specific serial interfaces with protocols 0x30, 0x40, and
0x60.
Relevant output from usb-devices:
T: Bus=04 Lev=01 Prnt=01 Port=00 Cnt=01 Dev#= 4 Spd=5000 MxCh= 0
D: Ver= 3.20 Cls=ef(misc ) Sub=02 Prot=01 MxPS= 9 #Cfgs= 1
P: Vendor=04b7 ProdID=8217 Rev=05.04
S: Manufacturer=COMPAL
S: Product=EXM-G1x
C: #Ifs= 6 Cfg#= 1 Atr=a0 MxPwr=896mA
I: If#= 0 Alt= 0 #EPs= 2 Cls=ff(vend.) Sub=ff Prot=30 Driver=option
I: If#= 1 Alt= 0 #EPs= 2 Cls=ff(vend.) Sub=42 Prot=01 Driver=(none)
I: If#= 2 Alt= 0 #EPs= 3 Cls=ff(vend.) Sub=ff Prot=60 Driver=option
I: If#= 3 Alt= 0 #EPs= 3 Cls=ff(vend.) Sub=ff Prot=40 Driver=option
I: If#= 4 Alt= 0 #EPs= 1 Cls=ff(vend.) Sub=ff Prot=ff Driver=(none)
I: If#= 8 Alt= 0 #EPs= 3 Cls=ff(vend.) Sub=ff Prot=50 Driver=qmi_wwan
Tested on a Compal EXM-G1x modem.
Assisted-by: Codex:GPT-5
Signed-off-by: Ian Lin <jisayme@xxxxxxxxx>
---
v3:
- base on usb-next
- add AI assistance attribution
- post as a fresh thread
v2: https://lore.kernel.org/20260828082645.13018-1-jisayme@xxxxxxxxx/
- split USB serial support into a separate patch
- identify the Qualcomm SDX12 chipset and include usb-devices output
- keep the device entries sorted and add the product name
v1: https://lore.kernel.org/20260828075644.6228-1-jisayme@xxxxxxxxx/
drivers/usb/serial/option.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/drivers/usb/serial/option.c b/drivers/usb/serial/option.c
index fd8f96294..8713f8b93 100644
--- a/drivers/usb/serial/option.c
+++ b/drivers/usb/serial/option.c
@@ -2541,6 +2541,9 @@ static const struct usb_device_id option_ids[] = {
{ USB_DEVICE_AND_INTERFACE_INFO(UNISOC_VENDOR_ID, TOZED_PRODUCT_LT70C, 0xff, 0, 0) },
{ USB_DEVICE_AND_INTERFACE_INFO(UNISOC_VENDOR_ID, UNISOC_PRODUCT_UIS7720, 0xff, 0, 0) },
{ USB_DEVICE_AND_INTERFACE_INFO(UNISOC_VENDOR_ID, LUAT_PRODUCT_AIR720U, 0xff, 0, 0) },
+ { USB_DEVICE_AND_INTERFACE_INFO(0x04b7, 0x8217, 0xff, 0xff, 0x30) }, /* Compal EXM-G1x */
+ { USB_DEVICE_AND_INTERFACE_INFO(0x04b7, 0x8217, 0xff, 0xff, 0x40) },
+ { USB_DEVICE_AND_INTERFACE_INFO(0x04b7, 0x8217, 0xff, 0xff, 0x60) },
{ USB_DEVICE_INTERFACE_CLASS(0x1bbb, 0x0530, 0xff), /* TCL IK512 MBIM */
.driver_info = NCTRL(1) },
{ USB_DEVICE_INTERFACE_CLASS(0x1bbb, 0x0640, 0xff), /* TCL IK512 ECM */
base-commit: 15734de99517b0c81a1a5a3bccaff4593ef8d953
--
2.43.0