diff --git a/sys/arm/freescale/vybrid/vf_ehci.c b/sys/arm/freescale/vybrid/vf_ehci.c
--- a/sys/arm/freescale/vybrid/vf_ehci.c
+++ b/sys/arm/freescale/vybrid/vf_ehci.c
@@ -386,7 +386,7 @@
 	sc = &esc->base;
 
 	/* First detach all children; we can't detach if that fails. */
-	if ((err = device_delete_children(dev)) != 0)
+	if ((err = bus_generic_detach(dev)) != 0)
 		return (err);
 
 	/*
diff --git a/sys/arm/mv/a37x0_spi.c b/sys/arm/mv/a37x0_spi.c
--- a/sys/arm/mv/a37x0_spi.c
+++ b/sys/arm/mv/a37x0_spi.c
@@ -227,7 +227,7 @@
 	int err;
 	struct a37x0_spi_softc *sc;
 
-	if ((err = device_delete_children(dev)) != 0)
+	if ((err = bus_generic_detach(dev)) != 0)
 		return (err);
 	sc = device_get_softc(dev);
 	mtx_destroy(&sc->sc_mtx);
diff --git a/sys/arm/nvidia/tegra_ehci.c b/sys/arm/nvidia/tegra_ehci.c
--- a/sys/arm/nvidia/tegra_ehci.c
+++ b/sys/arm/nvidia/tegra_ehci.c
@@ -113,14 +113,17 @@
 {
 	struct tegra_ehci_softc *sc;
 	ehci_softc_t *esc;
+	int error;
+
+	error = bus_generic_detach(dev);
+	if (error != 0)
+		return (error);
 
 	sc = device_get_softc(dev);
 
 	esc = &sc->ehci_softc;
 	if (sc->clk != NULL)
 		clk_release(sc->clk);
-	if (esc->sc_bus.bdev != NULL)
-		device_delete_child(dev, esc->sc_bus.bdev);
 	if (esc->sc_flags & EHCI_SCFLG_DONEINIT)
 		ehci_detach(esc);
 	if (esc->sc_intr_hdl != NULL)
@@ -135,9 +138,6 @@
 	if (sc->usb_alloc_called)
 		usb_bus_mem_free_all(&esc->sc_bus, &ehci_iterate_hw_softc);
 
-	/* During module unload there are lots of children leftover. */
-	device_delete_children(dev);
-
 	return (0);
 }
 
diff --git a/sys/arm/nvidia/tegra_xhci.c b/sys/arm/nvidia/tegra_xhci.c
--- a/sys/arm/nvidia/tegra_xhci.c
+++ b/sys/arm/nvidia/tegra_xhci.c
@@ -916,12 +916,16 @@
 {
 	struct tegra_xhci_softc *sc;
 	struct xhci_softc *xsc;
+	int error;
 
 	sc = device_get_softc(dev);
 	xsc = &sc->xhci_softc;
 
 	/* during module unload there are lots of children leftover */
-	device_delete_children(dev);
+	error = bus_generic_detach(dev);
+	if (error != 0)
+		return (error);
+
 	if (sc->xhci_inited) {
 		usb_callout_drain(&xsc->sc_callout);
 		xhci_halt_controller(xsc);
diff --git a/sys/arm/ti/am335x/am335x_musb.c b/sys/arm/ti/am335x/am335x_musb.c
--- a/sys/arm/ti/am335x/am335x_musb.c
+++ b/sys/arm/ti/am335x/am335x_musb.c
@@ -404,9 +404,12 @@
 musbotg_detach(device_t dev)
 {
 	struct musbotg_super_softc *sc = device_get_softc(dev);
+	int error;
 
 	/* during module unload there are lots of children leftover */
-	device_delete_children(dev);
+	error = bus_generic_detach(dev);
+	if (error != 0)
+		return (error);
 
 	if (sc->sc_otg.sc_irq_res && sc->sc_otg.sc_intr_hdl) {
 		/*
diff --git a/sys/arm/ti/usb/omap_ehci.c b/sys/arm/ti/usb/omap_ehci.c
--- a/sys/arm/ti/usb/omap_ehci.c
+++ b/sys/arm/ti/usb/omap_ehci.c
@@ -406,7 +406,9 @@
 	int err;
 
 	/* during module unload there are lots of children leftover */
-	device_delete_children(dev);
+	err = bus_generic_detach(dev);
+	if (err != 0)
+		return (err);
 
 	/*
 	 * disable interrupts that might have been switched on in ehci_init
diff --git a/sys/arm/ti/usb/omap_host.c b/sys/arm/ti/usb/omap_host.c
--- a/sys/arm/ti/usb/omap_host.c
+++ b/sys/arm/ti/usb/omap_host.c
@@ -432,9 +432,12 @@
 omap_uhh_detach(device_t dev)
 {
 	struct omap_uhh_softc *isc = device_get_softc(dev);
+	int error;
 
 	/* during module unload there are lots of children leftover */
-	device_delete_children(dev);
+	error = bus_generic_detach(dev);
+	if (error != 0)
+		return (error);
 
 	if (isc->uhh_mem_res) {
 		bus_release_resource(dev, SYS_RES_MEMORY, 0, isc->uhh_mem_res);
diff --git a/sys/arm/xilinx/zy7_ehci.c b/sys/arm/xilinx/zy7_ehci.c
--- a/sys/arm/xilinx/zy7_ehci.c
+++ b/sys/arm/xilinx/zy7_ehci.c
@@ -315,9 +315,12 @@
 zy7_ehci_detach(device_t dev)
 {
 	ehci_softc_t *sc = device_get_softc(dev);
+	int error;
 
 	/* during module unload there are lots of children leftover */
-	device_delete_children(dev);
+	error = bus_generic_detach(dev);
+	if (error != 0)
+		return (error);
 
 	if ((sc->sc_flags & EHCI_SCFLG_DONEINIT) != 0) {
 		ehci_detach(sc);
diff --git a/sys/dev/ahci/ahci.c b/sys/dev/ahci/ahci.c
--- a/sys/dev/ahci/ahci.c
+++ b/sys/dev/ahci/ahci.c
@@ -391,10 +391,12 @@
 ahci_detach(device_t dev)
 {
 	struct ahci_controller *ctlr = device_get_softc(dev);
-	int i;
+	int error, i;
 
 	/* Detach & delete all children */
-	device_delete_children(dev);
+	error = bus_generic_detach(dev);
+	if (error != 0)
+		return (error);
 
 	/* Free interrupts. */
 	for (i = 0; i < ctlr->numirqs; i++) {
diff --git a/sys/dev/ata/ata-pci.c b/sys/dev/ata/ata-pci.c
--- a/sys/dev/ata/ata-pci.c
+++ b/sys/dev/ata/ata-pci.c
@@ -134,9 +134,12 @@
 ata_pci_detach(device_t dev)
 {
     struct ata_pci_controller *ctlr = device_get_softc(dev);
+    int error;
 
     /* detach & delete all children */
-    device_delete_children(dev);
+    error = bus_generic_detach(dev);
+    if (error != 0)
+	return (error);
 
     if (ctlr->r_irq) {
 	bus_teardown_intr(dev, ctlr->r_irq, ctlr->handle);
diff --git a/sys/dev/atopcase/atopcase.c b/sys/dev/atopcase/atopcase.c
--- a/sys/dev/atopcase/atopcase.c
+++ b/sys/dev/atopcase/atopcase.c
@@ -545,7 +545,7 @@
 {
 	int err;
 
-	err = device_delete_children(sc->sc_dev);
+	err = bus_generic_detach(sc->sc_dev);
 	if (err)
 		return (err);
 
diff --git a/sys/dev/etherswitch/e6000sw/e6000sw.c b/sys/dev/etherswitch/e6000sw/e6000sw.c
--- a/sys/dev/etherswitch/e6000sw/e6000sw.c
+++ b/sys/dev/etherswitch/e6000sw/e6000sw.c
@@ -845,19 +845,21 @@
 static int
 e6000sw_detach(device_t dev)
 {
-	int phy;
+	int error, phy;
 	e6000sw_softc_t *sc;
 
 	sc = device_get_softc(dev);
 
+	error = bus_generic_detach(dev);
+	if (error != 0)
+		return (error);
+
 	if (device_is_attached(dev))
 		taskqueue_drain_timeout(sc->sc_tq, &sc->sc_tt);
 
 	if (sc->sc_tq != NULL)
 		taskqueue_free(sc->sc_tq);
 
-	device_delete_children(dev);
-
 	sx_destroy(&sc->sx);
 	for (phy = 0; phy < sc->num_ports; phy++) {
 		if (sc->ifp[phy] != NULL)
diff --git a/sys/dev/hyperv/input/hv_hid.c b/sys/dev/hyperv/input/hv_hid.c
--- a/sys/dev/hyperv/input/hv_hid.c
+++ b/sys/dev/hyperv/input/hv_hid.c
@@ -457,7 +457,7 @@
 	int		ret;
 
 	sc = device_get_softc(dev);
-	ret = device_delete_children(dev);
+	ret = bus_generic_detach(dev);
 	if (ret != 0)
 		return (ret);
 	if (sc->hs_xact_ctx != NULL)
diff --git a/sys/dev/iicbus/iicbus.c b/sys/dev/iicbus/iicbus.c
--- a/sys/dev/iicbus/iicbus.c
+++ b/sys/dev/iicbus/iicbus.c
@@ -144,7 +144,7 @@
 	struct iicbus_softc *sc = IICBUS_SOFTC(dev);
 	int err;
 
-	if ((err = device_delete_children(dev)) != 0)
+	if ((err = bus_generic_detach(dev)) != 0)
 		return (err);
 	iicbus_reset(dev, IIC_FASTEST, 0, NULL);
 	mtx_destroy(&sc->lock);
diff --git a/sys/dev/iicbus/iichid.c b/sys/dev/iicbus/iichid.c
--- a/sys/dev/iicbus/iichid.c
+++ b/sys/dev/iicbus/iichid.c
@@ -1218,7 +1218,7 @@
 	int error;
 
 	sc = device_get_softc(dev);
-	error = device_delete_children(dev);
+	error = bus_generic_detach(dev);
 	if (error)
 		return (error);
 	iichid_teardown_interrupt(sc);
diff --git a/sys/dev/intel/spi.c b/sys/dev/intel/spi.c
--- a/sys/dev/intel/spi.c
+++ b/sys/dev/intel/spi.c
@@ -550,9 +550,14 @@
 intelspi_detach(device_t dev)
 {
 	struct intelspi_softc	*sc;
+	int error;
 
 	sc = device_get_softc(dev);
 
+	error = bus_generic_detach(dev);
+	if (error != 0)
+		return (error);
+
 	INTELSPI_LOCK_DESTROY(sc);
 
 	if (sc->sc_irq_ih)
@@ -566,7 +571,7 @@
 		bus_release_resource(dev, SYS_RES_IRQ,
 		    sc->sc_irq_rid, sc->sc_irq_res);
 
-	return (device_delete_children(dev));
+	return (0);
 }
 
 int
diff --git a/sys/dev/mmc/host/dwmmc.c b/sys/dev/mmc/host/dwmmc.c
--- a/sys/dev/mmc/host/dwmmc.c
+++ b/sys/dev/mmc/host/dwmmc.c
@@ -778,7 +778,7 @@
 
 	sc = device_get_softc(dev);
 
-	ret = device_delete_children(dev);
+	ret = bus_generic_detach(dev);
 	if (ret != 0)
 		return (ret);
 
diff --git a/sys/dev/mvs/mvs_pci.c b/sys/dev/mvs/mvs_pci.c
--- a/sys/dev/mvs/mvs_pci.c
+++ b/sys/dev/mvs/mvs_pci.c
@@ -176,9 +176,12 @@
 mvs_detach(device_t dev)
 {
 	struct mvs_controller *ctlr = device_get_softc(dev);
+	int error;
 
 	/* Detach & delete all children */
-	device_delete_children(dev);
+	error = bus_generic_detach(dev);
+	if (error != 0)
+		return (error);
 
 	/* Free interrupt. */
 	if (ctlr->irq.r_irq) {
diff --git a/sys/dev/mvs/mvs_soc.c b/sys/dev/mvs/mvs_soc.c
--- a/sys/dev/mvs/mvs_soc.c
+++ b/sys/dev/mvs/mvs_soc.c
@@ -180,9 +180,12 @@
 mvs_detach(device_t dev)
 {
 	struct mvs_controller *ctlr = device_get_softc(dev);
+	int error;
 
 	/* Detach & delete all children */
-	device_delete_children(dev);
+	error = bus_generic_detach(dev);
+	if (error != 0)
+		return (error);
 
 	/* Free interrupt. */
 	if (ctlr->irq.r_irq) {
diff --git a/sys/dev/neta/if_mvneta.c b/sys/dev/neta/if_mvneta.c
--- a/sys/dev/neta/if_mvneta.c
+++ b/sys/dev/neta/if_mvneta.c
@@ -843,7 +843,7 @@
 	for (q = 0; q < MVNETA_TX_QNUM_MAX; q++)
 		mvneta_ring_dealloc_tx_queue(sc, q);
 
-	device_delete_children(dev);
+	bus_generic_detach(dev);
 
 	if (sc->ih_cookie[0] != NULL)
 		bus_teardown_intr(dev, sc->res[1], sc->ih_cookie[0]);
diff --git a/sys/dev/ow/owc_gpiobus.c b/sys/dev/ow/owc_gpiobus.c
--- a/sys/dev/ow/owc_gpiobus.c
+++ b/sys/dev/ow/owc_gpiobus.c
@@ -146,7 +146,7 @@
 
 	sc = device_get_softc(dev);
 
-	if ((err = device_delete_children(dev)) != 0)
+	if ((err = bus_generic_detach(dev)) != 0)
 		return (err);
 
 	gpio_pin_release(sc->sc_pin);
diff --git a/sys/dev/p2sb/p2sb.c b/sys/dev/p2sb/p2sb.c
--- a/sys/dev/p2sb/p2sb.c
+++ b/sys/dev/p2sb/p2sb.c
@@ -159,9 +159,13 @@
 p2sb_detach(device_t dev)
 {
 	struct p2sb_softc *sc;
+	int error;
 
 	/* Teardown the state in our softc created in our attach routine. */
-	device_delete_children(dev);
+	error = bus_generic_detach(dev);
+	if (error != 0)
+		return (error);
+
 	sc = device_get_softc(dev);
 	mtx_destroy(&sc->mutex);
 	if (sc->res != NULL)
diff --git a/sys/dev/ppc/ppc.c b/sys/dev/ppc/ppc.c
--- a/sys/dev/ppc/ppc.c
+++ b/sys/dev/ppc/ppc.c
@@ -1815,13 +1815,16 @@
 ppc_detach(device_t dev)
 {
 	struct ppc_data *ppc = DEVTOSOFTC(dev);
+	int error;
 
 	if (ppc->res_irq == 0) {
 		return (ENXIO);
 	}
 
 	/* detach & delete all children */
-	device_delete_children(dev);
+	error = bus_generic_detach(dev);
+	if (error != 0)
+		return (error);
 
 	if (ppc->res_irq != 0) {
 		bus_teardown_intr(dev, ppc->res_irq, ppc->intr_cookie);
diff --git a/sys/dev/rtsx/rtsx.c b/sys/dev/rtsx/rtsx.c
--- a/sys/dev/rtsx/rtsx.c
+++ b/sys/dev/rtsx/rtsx.c
@@ -3784,10 +3784,10 @@
 	WRITE4(sc, RTSX_BIER, sc->rtsx_intr_enabled);
 
 	/* Stop device. */
-	error = device_delete_children(sc->rtsx_dev);
+	error = bus_generic_detach(sc->rtsx_dev);
+	if (error)
+		return (error);
 	sc->rtsx_mmc_dev = NULL;
-	if (error)
-		return (error);
 
 	taskqueue_drain_timeout(taskqueue_swi_giant, &sc->rtsx_card_insert_task);
 	taskqueue_drain(taskqueue_swi_giant, &sc->rtsx_card_remove_task);
diff --git a/sys/dev/siis/siis.c b/sys/dev/siis/siis.c
--- a/sys/dev/siis/siis.c
+++ b/sys/dev/siis/siis.c
@@ -203,9 +203,12 @@
 siis_detach(device_t dev)
 {
 	struct siis_controller *ctlr = device_get_softc(dev);
+	int error;
 
 	/* Detach & delete all children */
-	device_delete_children(dev);
+	error = bus_generic_detach(dev);
+	if (error != 0)
+		return (error);
 
 	/* Free interrupts. */
 	if (ctlr->irq.r_irq) {
diff --git a/sys/dev/sound/pci/hda/hdaa.c b/sys/dev/sound/pci/hda/hdaa.c
--- a/sys/dev/sound/pci/hda/hdaa.c
+++ b/sys/dev/sound/pci/hda/hdaa.c
@@ -6684,7 +6684,7 @@
 	struct hdaa_devinfo *devinfo = device_get_softc(dev);
 	int error;
 
-	if ((error = device_delete_children(dev)) != 0)
+	if ((error = bus_generic_detach(dev)) != 0)
 		return (error);
 
 	hdaa_lock(devinfo);
diff --git a/sys/dev/sound/pci/hda/hdacc.c b/sys/dev/sound/pci/hda/hdacc.c
--- a/sys/dev/sound/pci/hda/hdacc.c
+++ b/sys/dev/sound/pci/hda/hdacc.c
@@ -541,7 +541,7 @@
 	struct hdacc_softc *codec = device_get_softc(dev);
 	int error;
 
-	if ((error = device_delete_children(dev)) != 0)
+	if ((error = bus_generic_detach(dev)) != 0)
 		return (error);
 	free(codec->fgs, M_HDACC);
 	return (0);
diff --git a/sys/dev/sound/pci/hdsp.c b/sys/dev/sound/pci/hdsp.c
--- a/sys/dev/sound/pci/hdsp.c
+++ b/sys/dev/sound/pci/hdsp.c
@@ -985,7 +985,7 @@
 		return (0);
 	}
 
-	err = device_delete_children(dev);
+	err = bus_generic_detach(dev);
 	if (err)
 		return (err);
 
diff --git a/sys/dev/sound/pci/hdspe.c b/sys/dev/sound/pci/hdspe.c
--- a/sys/dev/sound/pci/hdspe.c
+++ b/sys/dev/sound/pci/hdspe.c
@@ -877,7 +877,7 @@
 		return (0);
 	}
 
-	err = device_delete_children(dev);
+	err = bus_generic_detach(dev);
 	if (err)
 		return (err);
 
diff --git a/sys/dev/spibus/spibus.c b/sys/dev/spibus/spibus.c
--- a/sys/dev/spibus/spibus.c
+++ b/sys/dev/spibus/spibus.c
@@ -68,7 +68,7 @@
 int
 spibus_detach(device_t dev)
 {
-	return (device_delete_children(dev));
+	return (bus_generic_detach(dev));
 }
 
 static int
diff --git a/sys/dev/usb/controller/dwc_otg_acpi.c b/sys/dev/usb/controller/dwc_otg_acpi.c
--- a/sys/dev/usb/controller/dwc_otg_acpi.c
+++ b/sys/dev/usb/controller/dwc_otg_acpi.c
@@ -127,9 +127,12 @@
 dwc_otg_detach(device_t dev)
 {
 	struct dwc_otg_softc *sc = device_get_softc(dev);
+	int error;
 
 	/* during module unload there are lots of children leftover */
-	device_delete_children(dev);
+	error = bus_generic_detach(dev);
+	if (error != 0)
+		return (error);
 
 	if (sc->sc_irq_res && sc->sc_intr_hdl) {
 		/*
diff --git a/sys/dev/usb/controller/dwc_otg_fdt.c b/sys/dev/usb/controller/dwc_otg_fdt.c
--- a/sys/dev/usb/controller/dwc_otg_fdt.c
+++ b/sys/dev/usb/controller/dwc_otg_fdt.c
@@ -162,9 +162,12 @@
 dwc_otg_detach(device_t dev)
 {
 	struct dwc_otg_fdt_softc *sc = device_get_softc(dev);
+	int error;
 
 	/* during module unload there are lots of children leftover */
-	device_delete_children(dev);
+	error = bus_generic_detach(dev);
+	if (error != 0)
+		return (error);
 
 	if (sc->sc_otg.sc_irq_res && sc->sc_otg.sc_intr_hdl) {
 		/*
diff --git a/sys/dev/usb/controller/ehci_fsl.c b/sys/dev/usb/controller/ehci_fsl.c
--- a/sys/dev/usb/controller/ehci_fsl.c
+++ b/sys/dev/usb/controller/ehci_fsl.c
@@ -372,10 +372,14 @@
 static int
 fsl_ehci_detach(device_t self)
 {
-
 	int err;
 	ehci_softc_t *sc;
 
+	/* During module unload there are lots of children leftover */
+	err = bus_generic_detach(self);
+	if (err != 0)
+		return (err);
+
 	sc = device_get_softc(self);
 	/*
 	 * only call ehci_detach() after ehci_init()
@@ -399,14 +403,6 @@
 		sc->sc_intr_hdl = NULL;
 	}
 
-	if (sc->sc_bus.bdev) {
-		device_delete_child(self, sc->sc_bus.bdev);
-		sc->sc_bus.bdev = NULL;
-	}
-
-	/* During module unload there are lots of children leftover */
-	device_delete_children(self);
-
 	if (sc->sc_irq_res) {
 		bus_release_resource(self, SYS_RES_IRQ, 0, sc->sc_irq_res);
 		sc->sc_irq_res = NULL;
diff --git a/sys/dev/usb/controller/ehci_imx.c b/sys/dev/usb/controller/ehci_imx.c
--- a/sys/dev/usb/controller/ehci_imx.c
+++ b/sys/dev/usb/controller/ehci_imx.c
@@ -314,7 +314,7 @@
 	esc = &sc->ehci_softc;
 
 	/* First detach all children; we can't detach if that fails. */
-	if ((err = device_delete_children(dev)) != 0)
+	if ((err = bus_generic_detach(dev)) != 0)
 		return (err);
 
 	if (esc->sc_flags & EHCI_SCFLG_DONEINIT)
diff --git a/sys/dev/usb/controller/ehci_msm.c b/sys/dev/usb/controller/ehci_msm.c
--- a/sys/dev/usb/controller/ehci_msm.c
+++ b/sys/dev/usb/controller/ehci_msm.c
@@ -171,13 +171,9 @@
 
 	sc = device_get_softc(dev);
 
-	if (sc->sc_bus.bdev) {
-		bdev = sc->sc_bus.bdev;
-		device_detach(bdev);
-		device_delete_child(dev, bdev);
-	}
-
-	device_delete_children(dev);
+	err = bus_generic_detach(dev);
+	if (err != 0)
+		return (err);
 
 	if (sc->sc_irq_res && sc->sc_intr_hdl) {
 		/* only call ehci_detach() after ehci_init() */
diff --git a/sys/dev/usb/controller/ehci_mv.c b/sys/dev/usb/controller/ehci_mv.c
--- a/sys/dev/usb/controller/ehci_mv.c
+++ b/sys/dev/usb/controller/ehci_mv.c
@@ -283,7 +283,9 @@
 	int err;
 
 	/* during module unload there are lots of children leftover */
-	device_delete_children(self);
+	err = bus_generic_detach(self);
+	if (err != 0)
+		return (err);
 
 	/*
 	 * disable interrupts that might have been switched on in mv_ehci_attach
diff --git a/sys/dev/usb/controller/ehci_pci.c b/sys/dev/usb/controller/ehci_pci.c
--- a/sys/dev/usb/controller/ehci_pci.c
+++ b/sys/dev/usb/controller/ehci_pci.c
@@ -505,9 +505,12 @@
 ehci_pci_detach(device_t self)
 {
 	ehci_softc_t *sc = device_get_softc(self);
+	int error;
 
 	/* during module unload there are lots of children leftover */
-	device_delete_children(self);
+	error = bus_generic_detach(self);
+	if (error != 0)
+		return (error);
 
 	pci_disable_busmaster(self);
 
diff --git a/sys/dev/usb/controller/generic_ehci.c b/sys/dev/usb/controller/generic_ehci.c
--- a/sys/dev/usb/controller/generic_ehci.c
+++ b/sys/dev/usb/controller/generic_ehci.c
@@ -139,7 +139,9 @@
 	int err;
 
 	/* during module unload there are lots of children leftover */
-	device_delete_children(self);
+	err = bus_generic_detach(self);
+	if (err != 0)
+		return (err);
 
 	if (sc->sc_irq_res && sc->sc_intr_hdl) {
 		/*
diff --git a/sys/dev/usb/controller/generic_ohci.c b/sys/dev/usb/controller/generic_ohci.c
--- a/sys/dev/usb/controller/generic_ohci.c
+++ b/sys/dev/usb/controller/generic_ohci.c
@@ -231,7 +231,9 @@
 	struct hwrst_list *rst, *rst_tmp;
 
 	/* during module unload there are lots of children leftover */
-	device_delete_children(dev);
+	err = bus_generic_detach(dev);
+	if (err != 0)
+		return (err);
 
 	/*
 	 * Put the controller into reset, then disable clocks and do
diff --git a/sys/dev/usb/controller/generic_xhci.c b/sys/dev/usb/controller/generic_xhci.c
--- a/sys/dev/usb/controller/generic_xhci.c
+++ b/sys/dev/usb/controller/generic_xhci.c
@@ -152,7 +152,9 @@
 	int err;
 
 	/* during module unload there are lots of children leftover */
-	device_delete_children(dev);
+	err = bus_generic_detach(dev);
+	if (err != 0)
+		return (err);
 
 	if (sc->sc_irq_res != NULL && sc->sc_intr_hdl != NULL) {
 		err = bus_teardown_intr(dev, sc->sc_irq_res, sc->sc_intr_hdl);
diff --git a/sys/dev/usb/controller/musb_otg_allwinner.c b/sys/dev/usb/controller/musb_otg_allwinner.c
--- a/sys/dev/usb/controller/musb_otg_allwinner.c
+++ b/sys/dev/usb/controller/musb_otg_allwinner.c
@@ -561,17 +561,14 @@
 awusbdrd_detach(device_t dev)
 {
 	struct awusbdrd_softc *sc;
-	device_t bdev;
 	int error;
 
+	error = bus_generic_detach(dev);
+	if (error != 0)
+		return (error);
+
 	sc = device_get_softc(dev);
 
-	if (sc->sc.sc_bus.bdev != NULL) {
-		bdev = sc->sc.sc_bus.bdev;
-		device_detach(bdev);
-		device_delete_child(dev, bdev);
-	}
-
 	musbotg_uninit(&sc->sc);
 	error = bus_teardown_intr(dev, sc->res[1], sc->sc.sc_intr_hdl);
 	if (error != 0)
@@ -594,8 +591,6 @@
 
 	bus_release_resources(dev, awusbdrd_spec, sc->res);
 
-	device_delete_children(dev);
-
 	return (0);
 }
 
diff --git a/sys/dev/usb/controller/ohci_pci.c b/sys/dev/usb/controller/ohci_pci.c
--- a/sys/dev/usb/controller/ohci_pci.c
+++ b/sys/dev/usb/controller/ohci_pci.c
@@ -320,9 +320,12 @@
 ohci_pci_detach(device_t self)
 {
 	ohci_softc_t *sc = device_get_softc(self);
+	int error;
 
 	/* during module unload there are lots of children leftover */
-	device_delete_children(self);
+	error = bus_generic_detach(self);
+	if (error != 0)
+		return (error);
 
 	pci_disable_busmaster(self);
 
diff --git a/sys/dev/usb/controller/uhci_pci.c b/sys/dev/usb/controller/uhci_pci.c
--- a/sys/dev/usb/controller/uhci_pci.c
+++ b/sys/dev/usb/controller/uhci_pci.c
@@ -414,9 +414,12 @@
 uhci_pci_detach(device_t self)
 {
 	uhci_softc_t *sc = device_get_softc(self);
+	int error;
 
 	/* during module unload there are lots of children leftover */
-	device_delete_children(self);
+	error = bus_generic_detach(self);
+	if (error != 0)
+		return (error);
 
 	/*
 	 * disable interrupts that might have been switched on in
diff --git a/sys/dev/usb/controller/xhci_pci.c b/sys/dev/usb/controller/xhci_pci.c
--- a/sys/dev/usb/controller/xhci_pci.c
+++ b/sys/dev/usb/controller/xhci_pci.c
@@ -465,9 +465,12 @@
 xhci_pci_detach(device_t self)
 {
 	struct xhci_softc *sc = device_get_softc(self);
+	int error;
 
 	/* during module unload there are lots of children leftover */
-	device_delete_children(self);
+	error = bus_generic_detach(self);
+	if (error != 0)
+		return (error);
 
 	usb_callout_drain(&sc->sc_callout);
 	xhci_halt_controller(sc);
diff --git a/sys/dev/usb/input/usbhid.c b/sys/dev/usb/input/usbhid.c
--- a/sys/dev/usb/input/usbhid.c
+++ b/sys/dev/usb/input/usbhid.c
@@ -851,8 +851,12 @@
 usbhid_detach(device_t dev)
 {
 	struct usbhid_softc *sc = device_get_softc(dev);
+	int error;
+
+	error = bus_generic_detach(dev);
+	if (error != 0)
+		return (error);
 
-	device_delete_children(dev);
 	mtx_destroy(&sc->sc_mtx);
 
 	return (0);
diff --git a/sys/dev/usb/video/udl.c b/sys/dev/usb/video/udl.c
--- a/sys/dev/usb/video/udl.c
+++ b/sys/dev/usb/video/udl.c
@@ -441,9 +441,12 @@
 udl_detach(device_t dev)
 {
 	struct udl_softc *sc = device_get_softc(dev);
+	int error;
 
 	/* delete all child devices */
-	device_delete_children(dev);
+	error = bus_generic_detach(dev);
+	if (error != 0)
+		return (error);
 
 	UDL_LOCK(sc);
 	sc->sc_gone = 1;