diff --git a/sys/dev/rtwn/rtl8812a/r12a_reg.h b/sys/dev/rtwn/rtl8812a/r12a_reg.h
index f1fc4ee2f302..c9a51c197acd 100644
--- a/sys/dev/rtwn/rtl8812a/r12a_reg.h
+++ b/sys/dev/rtwn/rtl8812a/r12a_reg.h
@@ -34,6 +34,7 @@
  */
 /* System Configuration. */
 #define R12A_SDIO_CTRL			0x070
+#define R12A_OPT_CTRL			0x074
 #define R12A_RF_B_CTRL			0x076
 /* Rx DMA Configuration. */
 #define R12A_RXDMA_PRO			0x290
diff --git a/sys/dev/rtwn/rtl8812a/usb/r12au_attach.c b/sys/dev/rtwn/rtl8812a/usb/r12au_attach.c
index b6850eb9fa23..17f5388ff3a7 100644
--- a/sys/dev/rtwn/rtl8812a/usb/r12au_attach.c
+++ b/sys/dev/rtwn/rtl8812a/usb/r12au_attach.c
@@ -105,6 +105,86 @@ r12au_postattach(struct rtwn_softc *sc)
 	sc->sc_ic.ic_ioctl = r12a_ioctl_net;
 }
 
+/*
+ * These are inspired from github.com/aircrack-ng/rtl8812au/ in usb_halinit.c
+ */
+
+void r12a_switch_to_usb3(struct rtwn_softc *sc);
+void r12a_switch_to_usb2(struct rtwn_softc *sc);
+
+void
+r12a_switch_to_usb3(struct rtwn_softc *sc)
+{
+	struct rtwn_usb_softc *uc = RTWN_USB_SOFTC(sc);
+	uint8_t val8;
+
+	if (usbd_get_speed(uc->uc_udev) == USB_SPEED_HIGH) {
+		val8 = rtwn_read_1(sc, R12A_OPT_CTRL); /* 0x70 */
+		device_printf(sc->sc_dev, "%s: 0x74 was 0x%x\n",
+		    __func__, val8);
+		/*
+		 * Check if it's already enabled; if so we leave things alone
+		 * to avoid being stuck in a reprobe loop.
+		 */
+		if ((val8 & 0x0c) == 0x08) {
+			return;
+		}
+		rtwn_write_1(sc, R12A_OPT_CTRL, 0x8); /* 0x74 */
+		rtwn_write_1(sc, R12A_SDIO_CTRL, 0x2); /* 0x70 */
+		rtwn_write_1(sc, R92C_ACLK_MON, 0x1); /* 0x3e */
+		rtwn_write_1(sc, 0x3d, 0x3);
+
+		/* usb disconnect */
+		rtwn_write_1(sc, R92C_APS_FSMCO + 1, 0x80);
+			/* 0x05 - high byte of FSMCO */
+	}
+
+	if (usbd_get_speed(uc->uc_udev) == USB_SPEED_SUPER) {
+		val8 = rtwn_read_1(sc, 0x70);
+		val8 &= 0x02;	/* bit 1 */
+		rtwn_write_1(sc, 0x70, val8);
+
+		val8 = rtwn_read_1(sc, 0x3e);
+		val8 &= 0x1;	/* bit 0 */
+		rtwn_write_1(sc, 0x3e, val8);
+	}
+}
+
+void
+r12a_switch_to_usb2(struct rtwn_softc *sc)
+{
+	struct rtwn_usb_softc *uc = RTWN_USB_SOFTC(sc);
+	uint8_t val8;
+
+	if (usbd_get_speed(uc->uc_udev) == USB_SPEED_SUPER) {
+		val8 = rtwn_read_1(sc, R12A_OPT_CTRL); /* 0x70 */
+		device_printf(sc->sc_dev, "%s: 0x74 was 0x%x\n",
+		    __func__, val8);
+
+		if ((val8 & 0x0c) == 0x04) {
+			return;
+		}
+		rtwn_write_1(sc, R12A_OPT_CTRL, 0x4); /* 0x74 */
+		rtwn_write_1(sc, R12A_SDIO_CTRL, 0x2); /* 0x70 */
+		rtwn_write_1(sc, R92C_ACLK_MON, 0x1); /* 0x3e */
+		rtwn_write_1(sc, 0x3d, 0x3);
+
+		/* usb disconnect */
+		rtwn_write_1(sc, R92C_APS_FSMCO + 1, 0x80);
+			/* 0x05 - high byte of FSMCO */
+	}
+
+	if (usbd_get_speed(uc->uc_udev) == USB_SPEED_HIGH) {
+		val8 = rtwn_read_1(sc, 0x70);
+		val8 &= 0x02;	/* bit 1 */
+		rtwn_write_1(sc, 0x70, val8);
+
+		val8 = rtwn_read_1(sc, 0x3e);
+		val8 &= 0x1;	/* bit 0 */
+		rtwn_write_1(sc, 0x3e, val8);
+	}
+}
+
 void
 r12a_vap_preattach(struct rtwn_softc *sc, struct ieee80211vap *vap)
 {
diff --git a/sys/dev/rtwn/usb/rtwn_usb_attach.c b/sys/dev/rtwn/usb/rtwn_usb_attach.c
index 4958939a768a..57c14856759c 100644
--- a/sys/dev/rtwn/usb/rtwn_usb_attach.c
+++ b/sys/dev/rtwn/usb/rtwn_usb_attach.c
@@ -379,6 +379,8 @@ rtwn_usb_sysctlattach(struct rtwn_softc *sc)
 		uc->uc_rx_buf_size = RTWN_USB_RXBUFSZ_MAX;
 }
 
+extern void r12a_switch_to_usb3(struct rtwn_softc *sc);
+
 static int
 rtwn_usb_attach(device_t self)
 {
@@ -401,6 +403,22 @@ rtwn_usb_attach(device_t self)
 	rtwn_usb_attach_methods(sc);
 	rtwn_usb_attach_private(uc, USB_GET_DRIVER_INFO(uaa));
 
+	/* Temp hack - see if we're RTL8812AU in USB2 or USB3 mode */
+	if (usbd_get_speed(uc->uc_udev) == USB_SPEED_SUPER) {
+		device_printf(sc->sc_dev, "%s: SUPER speed\n", __func__);
+	}
+	else if (usbd_get_speed(uc->uc_udev) == USB_SPEED_HIGH) {
+		device_printf(sc->sc_dev, "%s: HIGH speed\n", __func__);
+		RTWN_LOCK(sc);
+		r12a_switch_to_usb3(sc);
+		RTWN_UNLOCK(sc);
+		//error = ENXIO;
+		//goto detach;
+	} else
+		device_printf(sc->sc_dev,
+		    "%s: .. unknown usb speed (%d)\n", __func__,
+		    usbd_get_speed(uc->uc_udev));
+
 	error = rtwn_usb_setup_endpoints(uc);
 	if (error != 0)
 		goto detach;