Hi,

This diff adds CH9102 support.
Tested with NodeMCU esp8266 v3 ch9102x board.

ok?

Index: share/man/man4/uchcom.4
===================================================================
RCS file: /cvs/src/share/man/man4/uchcom.4,v
retrieving revision 1.3
diff -u -p -u -p -r1.3 uchcom.4
--- share/man/man4/uchcom.4	12 Apr 2024 00:43:32 -0000	1.3
+++ share/man/man4/uchcom.4	14 May 2024 03:20:37 -0000
@@ -19,18 +19,18 @@
 .Os
 .Sh NAME
 .Nm uchcom
-.Nd WinChipHead CH343/341/340 based USB serial adapter
+.Nd WinChipHead CH9102/343/341/340 based USB serial adapter
 .Sh SYNOPSIS
 .Cd "uchcom* at uhub?"
 .Cd "ucom* at uchcom?"
 .Sh DESCRIPTION
 The
 .Nm
-driver supports WinChipHead CH343/341/340 serial devices.
+driver supports WinChipHead CH9102/343/341/340 serial devices.
 .Pp
 The CH341/340 devices only support a variety of baud rates
 up to 921600.
-CH343 devices support any baud rate up to 6 Mbps.
+CH9102/343 devices support any baud rate up to 6 Mbps.
 .Sh SEE ALSO
 .Xr tty 4 ,
 .Xr ucom 4 ,
Index: share/man/man4/ucom.4
===================================================================
RCS file: /cvs/src/share/man/man4/ucom.4,v
retrieving revision 1.34
diff -u -p -u -p -r1.34 ucom.4
--- share/man/man4/ucom.4	12 Apr 2024 00:43:32 -0000	1.34
+++ share/man/man4/ucom.4	14 May 2024 03:20:37 -0000
@@ -38,7 +38,7 @@
 .Cd "ucom* at moscom?"	# MosChip Semiconductor MCS7703
 .Cd "ucom* at uark?"	# Arkmicro Technologies
 .Cd "ucom* at ubsa?"	# Belkin
-.Cd "ucom* at uchcom?"	# WinChipHead CH343/341/340
+.Cd "ucom* at uchcom?"	# WinChipHead CH9102/343/341/340
 .Cd "ucom* at ucycom?"	# Cypress
 .Cd "ucom* at uftdi?"	# FTDI
 .Cd "ucom* at uipaq?"	# iPAQ
Index: share/man/man4/usb.4
===================================================================
RCS file: /cvs/src/share/man/man4/usb.4,v
retrieving revision 1.218
diff -u -p -u -p -r1.218 usb.4
--- share/man/man4/usb.4	12 Apr 2024 00:43:32 -0000	1.218
+++ share/man/man4/usb.4	14 May 2024 03:20:37 -0000
@@ -179,7 +179,7 @@ Arkmicro Technologies ARK3116 based USB 
 .It Xr ubsa 4
 Belkin USB serial adapter
 .It Xr uchcom 4
-WinChipHead CH343/341/340 based USB serial adapter
+WinChipHead CH9102/343/341/340 based USB serial adapter
 .It Xr ucom 4
 USB tty support
 .It Xr ucrcom 4
Index: sys/dev/usb/uchcom.c
===================================================================
RCS file: /cvs/src/sys/dev/usb/uchcom.c,v
retrieving revision 1.34
diff -u -p -u -p -r1.34 uchcom.c
--- sys/dev/usb/uchcom.c	12 Apr 2024 00:43:32 -0000	1.34
+++ sys/dev/usb/uchcom.c	14 May 2024 03:20:38 -0000
@@ -31,7 +31,7 @@
  */
 
 /*
- * driver for WinChipHead CH343/341/340.
+ * driver for WinChipHead CH9102/343/341/340.
  */
 
 #include <sys/param.h>
@@ -249,7 +249,8 @@ static const struct usb_devno uchcom_dev
 	{ USB_VENDOR_WCH, USB_PRODUCT_WCH_CH341 },
 	{ USB_VENDOR_WCH2, USB_PRODUCT_WCH2_CH340 },
 	{ USB_VENDOR_WCH2, USB_PRODUCT_WCH2_CH341A },
-	{ USB_VENDOR_WCH2, USB_PRODUCT_WCH2_CH343 }
+	{ USB_VENDOR_WCH2, USB_PRODUCT_WCH2_CH343 },
+	{ USB_VENDOR_WCH2, USB_PRODUCT_WCH2_CH9102 }
 };
 
 struct cfdriver uchcom_cd = {
Index: sys/dev/usb/usbdevs
===================================================================
RCS file: /cvs/src/sys/dev/usb/usbdevs,v
retrieving revision 1.762
diff -u -p -u -p -r1.762 usbdevs
--- sys/dev/usb/usbdevs	6 May 2024 05:00:19 -0000	1.762
+++ sys/dev/usb/usbdevs	14 May 2024 03:20:38 -0000
@@ -4654,6 +4654,7 @@ product WAVESENSE JAZZ		0xaaaa	Jazz bloo
 product WCH CH341		0x5523	CH341 serial/parallel
 product WCH2 CH341A		0x5523	CH341A serial/parallel
 product WCH2 CH343		0x55d3	CH343 serial/parallel
+product WCH2 CH9102		0x55d4	CH9102 serial/parallel
 product WCH2 CH340		0x7523	CH340 serial/parallel
 product	WCH2 TEMPER		0xe025	TEMPer sensor