Hello,

Long time user, first time code contributor, please be gentle.

I have a USB wireless NIC that is unsupported in the GENERIC kernel, for 
which I offer a patch.

dmesg describes this as:
MAC/BB RTL8192EU, RF 6052 2T2R [MAC omitted]

usbdevs describes this as:
0bda:818c Realtek, 802.11n NIC
high speed, self powered, config 1, rev 2.00, iSerial [MAC omitted]

Following some advice I found given in a similar situation to another 
person 
(https://www.reddit.com/r/openbsd/comments/ujbfh0/comment/i7mx7rf/) I 
was able to build a kernel for which the NIC works.  Here is the patch.  
I believe that only the changes to if_urtwn.c and usbdevs are manual, 
and the changes to usbdevs.h and usbdevs_data.h are generated 
automatically by the build process.

Index: if_urtwn.c
===================================================================
RCS file: /cvs/src/sys/dev/usb/if_urtwn.c,v
retrieving revision 1.108
diff -u -p -u -p -r1.108 if_urtwn.c
--- if_urtwn.c    12 Jun 2023 11:27:30 -0000    1.108
+++ if_urtwn.c    6 May 2024 04:20:26 -0000
@@ -344,6 +344,7 @@ static const struct urtwn_type {
      /* URTWN_RTL8192EU */
      URTWN_DEV_8192EU(DLINK,        DWA131E1),
      URTWN_DEV_8192EU(REALTEK,    RTL8192EU),
+    URTWN_DEV_8192EU(REALTEK,    RTL8192EU_2),
      URTWN_DEV_8192EU(TPLINK,    RTL8192EU),
      URTWN_DEV_8192EU(TPLINK,    RTL8192EU_2),
      URTWN_DEV_8192EU(TPLINK,    RTL8192EU_3)
Index: usbdevs
===================================================================
RCS file: /cvs/src/sys/dev/usb/usbdevs,v
retrieving revision 1.760
diff -u -p -u -p -r1.760 usbdevs
--- usbdevs    27 Nov 2023 20:03:50 -0000    1.760
+++ usbdevs    6 May 2024 04:20:26 -0000
@@ -3808,6 +3808,7 @@ product REALTEK RTL8187        0x8187 RTL8187
  product REALTEK RTL8187B_0    0x8189    RTL8187B
  product REALTEK RTL8188CUS    0x818a    RTL8188CUS
  product REALTEK RTL8192EU    0x818b    RTL8192EU
+product REALTEK RTL8192EU_2    0x818c    RTL8192EU_2
  product REALTEK RTL8188CU_3    0x8191    RTL8188CU
  product REALTEK RTL8192U    0x8192    RTL8192U
  product REALTEK RTL8187B_1    0x8197    RTL8187B
Index: usbdevs.h
===================================================================
RCS file: /cvs/src/sys/dev/usb/usbdevs.h,v
retrieving revision 1.772
diff -u -p -u -p -r1.772 usbdevs.h
--- usbdevs.h    27 Nov 2023 20:04:07 -0000    1.772
+++ usbdevs.h    6 May 2024 04:20:26 -0000
@@ -1,4 +1,4 @@
-/*    $OpenBSD: usbdevs.h,v 1.772 2023/11/27 20:04:07 miod Exp $    */
+/*    $OpenBSD$    */

  /*
   * THIS FILE IS AUTOMATICALLY GENERATED.  DO NOT EDIT.
@@ -3815,6 +3815,7 @@
  #define    USB_PRODUCT_REALTEK_RTL8187B_0    0x8189        /* RTL8187B */
  #define    USB_PRODUCT_REALTEK_RTL8188CUS    0x818a        /* 
RTL8188CUS */
  #define    USB_PRODUCT_REALTEK_RTL8192EU    0x818b        /* RTL8192EU */
+#define    USB_PRODUCT_REALTEK_RTL8192EU_2    0x818c        /* 
RTL8192EU_2 */
  #define    USB_PRODUCT_REALTEK_RTL8188CU_3    0x8191        /* 
RTL8188CU */
  #define    USB_PRODUCT_REALTEK_RTL8192U    0x8192        /* RTL8192U */
  #define    USB_PRODUCT_REALTEK_RTL8187B_1    0x8197        /* RTL8187B */
Index: usbdevs_data.h
===================================================================
RCS file: /cvs/src/sys/dev/usb/usbdevs_data.h,v
retrieving revision 1.766
diff -u -p -u -p -r1.766 usbdevs_data.h
--- usbdevs_data.h    27 Nov 2023 20:04:07 -0000    1.766
+++ usbdevs_data.h    6 May 2024 04:20:26 -0000
@@ -1,4 +1,4 @@
-/*    $OpenBSD: usbdevs_data.h,v 1.766 2023/11/27 20:04:07 miod Exp $    */
+/*    $OpenBSD$    */

  /*
   * THIS FILE IS AUTOMATICALLY GENERATED.  DO NOT EDIT.
@@ -9516,6 +9516,10 @@ const struct usb_known_product usb_known
      {
          USB_VENDOR_REALTEK, USB_PRODUCT_REALTEK_RTL8192EU,
          "RTL8192EU",
+    },
+    {
+        USB_VENDOR_REALTEK, USB_PRODUCT_REALTEK_RTL8192EU_2,
+        "RTL8192EU_2",
      },
      {
          USB_VENDOR_REALTEK, USB_PRODUCT_REALTEK_RTL8188CU_3,

-- 
Kyle Markley