diff --git a/share/examples/drivers/make_device_driver.sh b/share/examples/drivers/make_device_driver.sh
--- a/share/examples/drivers/make_device_driver.sh
+++ b/share/examples/drivers/make_device_driver.sh
@@ -342,7 +342,8 @@
 		if ((ioport == 0) && (irq == 0))
 			return; /* We've added all our local hints. */
 
-		child = BUS_ADD_CHILD(parent, ISA_ORDER_SPECULATIVE, "${1}", -1);
+		child = BUS_ADD_CHILD(parent, ISA_ORDER_SPECULATIVE, "${1}",
+		    DEVICE_UNIT_ANY);
 		bus_set_resource(child, SYS_RES_IOPORT,	0, ioport, NUMPORTS);
 		bus_set_resource(child, SYS_RES_IRQ,	0, irq, 1);
 		bus_set_resource(child, SYS_RES_DRQ,	0, res[i].drq, 1);
diff --git a/stand/kshim/bsd_kernel.c b/stand/kshim/bsd_kernel.c
--- a/stand/kshim/bsd_kernel.c
+++ b/stand/kshim/bsd_kernel.c
@@ -1326,12 +1326,13 @@
 {
 	uint32_t x;
 
-	usb_pci_root = device_add_child(NULL, "pci", -1);
+	usb_pci_root = device_add_child(NULL, "pci", DEVICE_UNIT_ANY);
 	if (usb_pci_root == NULL)
 		return;
 
 	for (x = 0; x != USB_PCI_USB_MAX; x++) {
-		usb_pci_dev[x] = device_add_child(usb_pci_root, usb_pci_devices[x], -1);
+		usb_pci_dev[x] = device_add_child(usb_pci_root,
+		    usb_pci_devices[x], DEVICE_UNIT_ANY);
 		if (usb_pci_dev[x] == NULL)
 			continue;
 		if (device_probe_and_attach(usb_pci_dev[x])) {
diff --git a/sys/arm/broadcom/bcm2835/bcm2835_cpufreq.c b/sys/arm/broadcom/bcm2835/bcm2835_cpufreq.c
--- a/sys/arm/broadcom/bcm2835/bcm2835_cpufreq.c
+++ b/sys/arm/broadcom/bcm2835/bcm2835_cpufreq.c
@@ -1204,9 +1204,9 @@
 		return;
 
 	DPRINTF("driver=%p, parent=%p\n", driver, parent);
-	if (device_find_child(parent, "bcm2835_cpufreq", -1) != NULL)
+	if (device_find_child(parent, "bcm2835_cpufreq", DEVICE_UNIT_ANY) != NULL)
 		return;
-	if (BUS_ADD_CHILD(parent, 0, "bcm2835_cpufreq", -1) == NULL)
+	if (BUS_ADD_CHILD(parent, 0, "bcm2835_cpufreq", DEVICE_UNIT_ANY) == NULL)
 		device_printf(parent, "add child failed\n");
 }
 
diff --git a/sys/arm/nvidia/tegra124/tegra124_coretemp.c b/sys/arm/nvidia/tegra124/tegra124_coretemp.c
--- a/sys/arm/nvidia/tegra124/tegra124_coretemp.c
+++ b/sys/arm/nvidia/tegra124/tegra124_coretemp.c
@@ -176,9 +176,9 @@
 	root = OF_finddevice("/");
 	if (!ofw_bus_node_is_compatible(root, "nvidia,tegra124"))
 		return;
-	if (device_find_child(parent, "tegra124_coretemp", -1) != NULL)
+	if (device_find_child(parent, "tegra124_coretemp", DEVICE_UNIT_ANY) != NULL)
 		return;
-	if (BUS_ADD_CHILD(parent, 0, "tegra124_coretemp", -1) == NULL)
+	if (BUS_ADD_CHILD(parent, 0, "tegra124_coretemp", DEVICE_UNIT_ANY) == NULL)
 		device_printf(parent, "add child failed\n");
 }
 
diff --git a/sys/arm/nvidia/tegra124/tegra124_cpufreq.c b/sys/arm/nvidia/tegra124/tegra124_cpufreq.c
--- a/sys/arm/nvidia/tegra124/tegra124_cpufreq.c
+++ b/sys/arm/nvidia/tegra124/tegra124_cpufreq.c
@@ -475,9 +475,9 @@
 
 	if (device_get_unit(parent) != 0)
 		return;
-	if (device_find_child(parent, "tegra124_cpufreq", -1) != NULL)
+	if (device_find_child(parent, "tegra124_cpufreq", DEVICE_UNIT_ANY) != NULL)
 		return;
-	if (BUS_ADD_CHILD(parent, 0, "tegra124_cpufreq", -1) == NULL)
+	if (BUS_ADD_CHILD(parent, 0, "tegra124_cpufreq", DEVICE_UNIT_ANY) == NULL)
 		device_printf(parent, "add child failed\n");
 }
 
diff --git a/sys/arm/ti/am335x/am335x_ehrpwm.c b/sys/arm/ti/am335x/am335x_ehrpwm.c
--- a/sys/arm/ti/am335x/am335x_ehrpwm.c
+++ b/sys/arm/ti/am335x/am335x_ehrpwm.c
@@ -512,7 +512,8 @@
 	reg |= TBCTL_CTRMODE_UP | TBCTL_FREERUN;
 	EPWM_WRITE2(sc, EPWM_TBCTL, reg);
 
-	if ((sc->sc_busdev = device_add_child(dev, "pwmbus", -1)) == NULL) {
+	if ((sc->sc_busdev = device_add_child(dev, "pwmbus",
+	    DEVICE_UNIT_ANY)) == NULL) {
 		device_printf(dev, "Cannot add child pwmbus\n");
 		// This driver can still do things even without the bus child.
 	}
diff --git a/sys/arm/ti/am335x/am335x_scm.c b/sys/arm/ti/am335x/am335x_scm.c
--- a/sys/arm/ti/am335x/am335x_scm.c
+++ b/sys/arm/ti/am335x/am335x_scm.c
@@ -86,7 +86,7 @@
 		return;
 
 	/* Make sure we attach only once. */
-	if (device_find_child(parent, "am335x_scm", -1) != NULL)
+	if (device_find_child(parent, "am335x_scm", DEVICE_UNIT_ANY) != NULL)
 		return;
 
 	child = device_add_child(parent, "am335x_scm", DEVICE_UNIT_ANY);
diff --git a/sys/arm/ti/ti_i2c.c b/sys/arm/ti/ti_i2c.c
--- a/sys/arm/ti/ti_i2c.c
+++ b/sys/arm/ti/ti_i2c.c
@@ -851,7 +851,8 @@
 		goto out;
 
 	/* Attach the iicbus. */
-	if ((sc->sc_iicbus = device_add_child(dev, "iicbus", -1)) == NULL) {
+	if ((sc->sc_iicbus = device_add_child(dev, "iicbus",
+	    DEVICE_UNIT_ANY)) == NULL) {
 		device_printf(dev, "could not allocate iicbus instance\n");
 		err = ENXIO;
 		goto out;
diff --git a/sys/arm64/arm64/gic_v3_acpi.c b/sys/arm64/arm64/gic_v3_acpi.c
--- a/sys/arm64/arm64/gic_v3_acpi.c
+++ b/sys/arm64/arm64/gic_v3_acpi.c
@@ -450,7 +450,7 @@
 	    gic_v3_add_children, dev);
 	/* Add the vgic child if needed */
 	if (((uintptr_t)acpi_get_private(dev) & GICV3_PRIV_FLAGS) != 0) {
-		child = device_add_child(dev, "vgic", -1);
+		child = device_add_child(dev, "vgic", DEVICE_UNIT_ANY);
 		if (child == NULL) {
 			device_printf(dev, "Could not add vgic child\n");
 		} else {
diff --git a/sys/arm64/arm64/gic_v3_fdt.c b/sys/arm64/arm64/gic_v3_fdt.c
--- a/sys/arm64/arm64/gic_v3_fdt.c
+++ b/sys/arm64/arm64/gic_v3_fdt.c
@@ -363,7 +363,7 @@
 	 * child so we can use this in the vmm module for bhyve.
 	 */
 	if (OF_hasprop(parent, "interrupts")) {
-		child = device_add_child(dev, "vgic", -1);
+		child = device_add_child(dev, "vgic", DEVICE_UNIT_ANY);
 		if (child == NULL) {
 			device_printf(dev, "Could not add vgic child\n");
 		} else {
diff --git a/sys/arm64/cavium/thunder_pcie_fdt.c b/sys/arm64/cavium/thunder_pcie_fdt.c
--- a/sys/arm64/cavium/thunder_pcie_fdt.c
+++ b/sys/arm64/cavium/thunder_pcie_fdt.c
@@ -152,7 +152,7 @@
 			ofw_bus_intr_to_rl(dev, node, &di->di_rl, NULL);
 
 			/* Add newbus device for this FDT node */
-			child = device_add_child(dev, NULL, -1);
+			child = device_add_child(dev, NULL, DEVICE_UNIT_ANY);
 			if (child == NULL) {
 				resource_list_free(&di->di_rl);
 				ofw_bus_gen_destroy_devinfo(&di->di_dinfo);
diff --git a/sys/arm64/nvidia/tegra210/tegra210_coretemp.c b/sys/arm64/nvidia/tegra210/tegra210_coretemp.c
--- a/sys/arm64/nvidia/tegra210/tegra210_coretemp.c
+++ b/sys/arm64/nvidia/tegra210/tegra210_coretemp.c
@@ -181,9 +181,9 @@
 	root = OF_finddevice("/");
 	if (!ofw_bus_node_is_compatible(root, "nvidia,tegra210"))
 		return;
-	if (device_find_child(parent, "tegra210_coretemp", -1) != NULL)
+	if (device_find_child(parent, "tegra210_coretemp", DEVICE_UNIT_ANY) != NULL)
 		return;
-	if (BUS_ADD_CHILD(parent, 0, "tegra210_coretemp", -1) == NULL)
+	if (BUS_ADD_CHILD(parent, 0, "tegra210_coretemp", DEVICE_UNIT_ANY) == NULL)
 		device_printf(parent, "add child failed\n");
 }
 
diff --git a/sys/arm64/nvidia/tegra210/tegra210_cpufreq.c b/sys/arm64/nvidia/tegra210/tegra210_cpufreq.c
--- a/sys/arm64/nvidia/tegra210/tegra210_cpufreq.c
+++ b/sys/arm64/nvidia/tegra210/tegra210_cpufreq.c
@@ -393,9 +393,9 @@
 
 	if (device_get_unit(parent) != 0)
 		return;
-	if (device_find_child(parent, "tegra210_cpufreq", -1) != NULL)
+	if (device_find_child(parent, "tegra210_cpufreq", DEVICE_UNIT_ANY) != NULL)
 		return;
-	if (BUS_ADD_CHILD(parent, 0, "tegra210_cpufreq", -1) == NULL)
+	if (BUS_ADD_CHILD(parent, 0, "tegra210_cpufreq", DEVICE_UNIT_ANY) == NULL)
 		device_printf(parent, "add child failed\n");
 }
 
diff --git a/sys/compat/linuxkpi/common/src/linux_i2c.c b/sys/compat/linuxkpi/common/src/linux_i2c.c
--- a/sys/compat/linuxkpi/common/src/linux_i2c.c
+++ b/sys/compat/linuxkpi/common/src/linux_i2c.c
@@ -85,7 +85,7 @@
 	struct lkpi_iic_softc *sc;
 
 	sc = device_get_softc(dev);
-	sc->iicbus = device_add_child(dev, "iicbus", -1);
+	sc->iicbus = device_add_child(dev, "iicbus", DEVICE_UNIT_ANY);
 	if (sc->iicbus == NULL) {
 		device_printf(dev, "Couldn't add iicbus child, aborting\n");
 		return (ENXIO);
@@ -323,7 +323,8 @@
 		device_printf(adapter->dev.parent->bsddev,
 		    "Adding i2c adapter %s\n", adapter->name);
 	sx_xlock(&lkpi_sx_i2c);
-	lkpi_iic = device_add_child(adapter->dev.parent->bsddev, "lkpi_iic", -1);
+	lkpi_iic = device_add_child(adapter->dev.parent->bsddev, "lkpi_iic",
+	    DEVICE_UNIT_ANY);
 	if (lkpi_iic == NULL) {
 		device_printf(adapter->dev.parent->bsddev, "Couldn't add lkpi_iic\n");
 		sx_xunlock(&lkpi_sx_i2c);
diff --git a/sys/compat/linuxkpi/common/src/linux_i2cbb.c b/sys/compat/linuxkpi/common/src/linux_i2cbb.c
--- a/sys/compat/linuxkpi/common/src/linux_i2cbb.c
+++ b/sys/compat/linuxkpi/common/src/linux_i2cbb.c
@@ -90,7 +90,7 @@
 	struct lkpi_iicbb_softc *sc;
 
 	sc = device_get_softc(dev);
-	sc->iicbb = device_add_child(dev, "iicbb", -1);
+	sc->iicbb = device_add_child(dev, "iicbb", DEVICE_UNIT_ANY);
 	if (sc->iicbb == NULL) {
 		device_printf(dev, "Couldn't add iicbb child, aborting\n");
 		return (ENXIO);
@@ -308,7 +308,8 @@
 		device_printf(adapter->dev.parent->bsddev,
 		    "Adding i2c adapter %s\n", adapter->name);
 	sx_xlock(&lkpi_sx_i2cbb);
-	lkpi_iicbb = device_add_child(adapter->dev.parent->bsddev, "lkpi_iicbb", -1);
+	lkpi_iicbb = device_add_child(adapter->dev.parent->bsddev, "lkpi_iicbb",
+	    DEVICE_UNIT_ANY);
 	if (lkpi_iicbb == NULL) {
 		device_printf(adapter->dev.parent->bsddev, "Couldn't add lkpi_iicbb\n");
 		sx_xunlock(&lkpi_sx_i2cbb);
diff --git a/sys/crypto/aesni/aesni.c b/sys/crypto/aesni/aesni.c
--- a/sys/crypto/aesni/aesni.c
+++ b/sys/crypto/aesni/aesni.c
@@ -81,8 +81,8 @@
 {
 
 	/* NB: order 10 is so we get attached after h/w devices */
-	if (device_find_child(parent, "aesni", -1) == NULL &&
-	    BUS_ADD_CHILD(parent, 10, "aesni", -1) == 0)
+	if (device_find_child(parent, "aesni", DEVICE_UNIT_ANY) == NULL &&
+	    BUS_ADD_CHILD(parent, 10, "aesni", DEVICE_UNIT_ANY) == 0)
 		panic("aesni: could not attach");
 }
 
diff --git a/sys/crypto/armv8/armv8_crypto.c b/sys/crypto/armv8/armv8_crypto.c
--- a/sys/crypto/armv8/armv8_crypto.c
+++ b/sys/crypto/armv8/armv8_crypto.c
@@ -73,8 +73,8 @@
 {
 
 	/* NB: order 10 is so we get attached after h/w devices */
-	if (device_find_child(parent, "armv8crypto", -1) == NULL &&
-	    BUS_ADD_CHILD(parent, 10, "armv8crypto", -1) == 0)
+	if (device_find_child(parent, "armv8crypto", DEVICE_UNIT_ANY) == NULL &&
+	    BUS_ADD_CHILD(parent, 10, "armv8crypto", DEVICE_UNIT_ANY) == 0)
 		panic("ARMv8 crypto: could not attach");
 }
 
diff --git a/sys/crypto/blake2/blake2_cryptodev.c b/sys/crypto/blake2/blake2_cryptodev.c
--- a/sys/crypto/blake2/blake2_cryptodev.c
+++ b/sys/crypto/blake2/blake2_cryptodev.c
@@ -61,8 +61,8 @@
 {
 
 	/* NB: order 10 is so we get attached after h/w devices */
-	if (device_find_child(parent, "blaketwo", -1) == NULL &&
-	    BUS_ADD_CHILD(parent, 10, "blaketwo", -1) == 0)
+	if (device_find_child(parent, "blaketwo", DEVICE_UNIT_ANY) == NULL &&
+	    BUS_ADD_CHILD(parent, 10, "blaketwo", DEVICE_UNIT_ANY) == 0)
 		panic("blaketwo: could not attach");
 }
 
diff --git a/sys/crypto/openssl/ossl.c b/sys/crypto/openssl/ossl.c
--- a/sys/crypto/openssl/ossl.c
+++ b/sys/crypto/openssl/ossl.c
@@ -56,7 +56,7 @@
 ossl_identify(driver_t *driver, device_t parent)
 {
 
-	if (device_find_child(parent, "ossl", -1) == NULL)
+	if (device_find_child(parent, "ossl", DEVICE_UNIT_ANY) == NULL)
 		BUS_ADD_CHILD(parent, 10, "ossl", DEVICE_UNIT_ANY);
 }
 
diff --git a/sys/crypto/via/padlock.c b/sys/crypto/via/padlock.c
--- a/sys/crypto/via/padlock.c
+++ b/sys/crypto/via/padlock.c
@@ -71,8 +71,8 @@
 padlock_identify(driver_t *drv, device_t parent)
 {
 	/* NB: order 10 is so we get attached after h/w devices */
-	if (device_find_child(parent, "padlock", -1) == NULL &&
-	    BUS_ADD_CHILD(parent, 10, "padlock", -1) == 0)
+	if (device_find_child(parent, "padlock", DEVICE_UNIT_ANY) == NULL &&
+	    BUS_ADD_CHILD(parent, 10, "padlock", DEVICE_UNIT_ANY) == 0)
 		panic("padlock: could not attach");
 }
 
diff --git a/sys/dev/aac/aac.c b/sys/dev/aac/aac.c
--- a/sys/dev/aac/aac.c
+++ b/sys/dev/aac/aac.c
@@ -473,7 +473,7 @@
 		      mir->MntTable[0].FileSystemName,
 		      mir->MntTable[0].Capacity, mir->MntTable[0].VolType);
 
-		if ((child = device_add_child(sc->aac_dev, "aacd", -1)) == NULL)
+		if ((child = device_add_child(sc->aac_dev, "aacd", DEVICE_UNIT_ANY)) == NULL)
 			device_printf(sc->aac_dev, "device_add_child failed\n");
 		else
 			device_set_ivars(child, co);
diff --git a/sys/dev/acpi_support/acpi_asus_wmi.c b/sys/dev/acpi_support/acpi_asus_wmi.c
--- a/sys/dev/acpi_support/acpi_asus_wmi.c
+++ b/sys/dev/acpi_support/acpi_asus_wmi.c
@@ -454,7 +454,7 @@
 		return;
 
 	/* Add only a single device instance. */
-	if (device_find_child(parent, "acpi_asus_wmi", -1) != NULL)
+	if (device_find_child(parent, "acpi_asus_wmi", DEVICE_UNIT_ANY) != NULL)
 		return;
 
 	/* Check management GUID to see whether system is compatible. */
@@ -462,7 +462,7 @@
 	    ACPI_ASUS_WMI_MGMT_GUID))
 		return;
 
-	if (BUS_ADD_CHILD(parent, 0, "acpi_asus_wmi", -1) == NULL)
+	if (BUS_ADD_CHILD(parent, 0, "acpi_asus_wmi", DEVICE_UNIT_ANY) == NULL)
 		device_printf(parent, "add acpi_asus_wmi child failed\n");
 }
 
diff --git a/sys/dev/acpi_support/acpi_hp.c b/sys/dev/acpi_support/acpi_hp.c
--- a/sys/dev/acpi_support/acpi_hp.c
+++ b/sys/dev/acpi_support/acpi_hp.c
@@ -465,7 +465,7 @@
 		return;
 
 	/* Add only a single device instance. */
-	if (device_find_child(parent, "acpi_hp", -1) != NULL)
+	if (device_find_child(parent, "acpi_hp", DEVICE_UNIT_ANY) != NULL)
 		return;
 
 	/* Check BIOS GUID to see whether system is compatible. */
@@ -473,7 +473,7 @@
 	    ACPI_HP_WMI_BIOS_GUID))
 		return;
 
-	if (BUS_ADD_CHILD(parent, 0, "acpi_hp", -1) == NULL)
+	if (BUS_ADD_CHILD(parent, 0, "acpi_hp", DEVICE_UNIT_ANY) == NULL)
 		device_printf(parent, "add acpi_hp child failed\n");
 }
 
diff --git a/sys/dev/acpi_support/acpi_sbl_wmi.c b/sys/dev/acpi_support/acpi_sbl_wmi.c
--- a/sys/dev/acpi_support/acpi_sbl_wmi.c
+++ b/sys/dev/acpi_support/acpi_sbl_wmi.c
@@ -59,7 +59,7 @@
 		return;
 
 	/* Add only a single device instance. */
-	if (device_find_child(parent, "acpi_sbl_wmi", -1) != NULL)
+	if (device_find_child(parent, "acpi_sbl_wmi", DEVICE_UNIT_ANY) != NULL)
 		return;
 
 	/* Check management GUID to see whether system is compatible. */
@@ -67,7 +67,7 @@
 	    ACPI_SBL_FW_UPDATE_WMI_GUID))
 		return;
 
-	if (BUS_ADD_CHILD(parent, 0, "acpi_sbl_wmi", -1) == NULL)
+	if (BUS_ADD_CHILD(parent, 0, "acpi_sbl_wmi", DEVICE_UNIT_ANY) == NULL)
 		device_printf(parent, "add acpi_sbl_wmi child failed\n");
 }
 
diff --git a/sys/dev/acpica/acpi_pcib_acpi.c b/sys/dev/acpica/acpi_pcib_acpi.c
--- a/sys/dev/acpica/acpi_pcib_acpi.c
+++ b/sys/dev/acpica/acpi_pcib_acpi.c
@@ -473,7 +473,7 @@
     error = 0;
 
     bus_identify_children(dev);
-    if (device_add_child(dev, "pci", -1) == NULL) {
+    if (device_add_child(dev, "pci", DEVICE_UNIT_ANY) == NULL) {
 	bus_dma_tag_destroy(sc->ap_dma_tag);
 	sc->ap_dma_tag = NULL;
 	error = ENXIO;
diff --git a/sys/dev/acpica/acpi_perf.c b/sys/dev/acpica/acpi_perf.c
--- a/sys/dev/acpica/acpi_perf.c
+++ b/sys/dev/acpica/acpi_perf.c
@@ -142,7 +142,7 @@
 	device_t dev;
 
 	/* Make sure we're not being doubly invoked. */
-	if (device_find_child(parent, "acpi_perf", -1) != NULL)
+	if (device_find_child(parent, "acpi_perf", DEVICE_UNIT_ANY) != NULL)
 		return;
 
 	/* Get the handle for the Processor object and check for perf states. */
diff --git a/sys/dev/acpica/acpi_throttle.c b/sys/dev/acpica/acpi_throttle.c
--- a/sys/dev/acpica/acpi_throttle.c
+++ b/sys/dev/acpica/acpi_throttle.c
@@ -131,7 +131,7 @@
 	ACPI_OBJECT *obj;
 
 	/* Make sure we're not being doubly invoked. */
-	if (device_find_child(parent, "acpi_throttle", -1))
+	if (device_find_child(parent, "acpi_throttle", DEVICE_UNIT_ANY))
 		return;
 
 	/* Check for a valid duty width and parent CPU type. */
@@ -173,8 +173,8 @@
 	 * Since p4tcc uses the same mechanism (but internal to the CPU),
 	 * we disable acpi_throttle when p4tcc is also present.
 	 */
-	if (device_find_child(device_get_parent(dev), "p4tcc", -1) &&
-	    !resource_disabled("p4tcc", 0))
+	if (device_find_child(device_get_parent(dev), "p4tcc", DEVICE_UNIT_ANY)
+	    && !resource_disabled("p4tcc", 0))
 		return (ENXIO);
 
 	device_set_desc(dev, "ACPI CPU Throttling");
diff --git a/sys/dev/acpica/acpi_video.c b/sys/dev/acpica/acpi_video.c
--- a/sys/dev/acpica/acpi_video.c
+++ b/sys/dev/acpica/acpi_video.c
@@ -274,7 +274,7 @@
 acpi_video_identify(driver_t *driver, device_t parent)
 {
 
-	if (device_find_child(parent, "acpi_video", -1) == NULL)
+	if (device_find_child(parent, "acpi_video", DEVICE_UNIT_ANY) == NULL)
 		device_add_child(parent, "acpi_video", DEVICE_UNIT_ANY);
 }
 
diff --git a/sys/dev/agp/agp_i810.c b/sys/dev/agp/agp_i810.c
--- a/sys/dev/agp/agp_i810.c
+++ b/sys/dev/agp/agp_i810.c
@@ -680,7 +680,7 @@
 agp_i810_identify(driver_t *driver, device_t parent)
 {
 
-	if (device_find_child(parent, "agp", -1) == NULL &&
+	if (device_find_child(parent, "agp", DEVICE_UNIT_ANY) == NULL &&
 	    agp_i810_match(parent))
 		device_add_child(parent, "agp", DEVICE_UNIT_ANY);
 }
diff --git a/sys/dev/amdsbwd/amdsbwd.c b/sys/dev/amdsbwd/amdsbwd.c
--- a/sys/dev/amdsbwd/amdsbwd.c
+++ b/sys/dev/amdsbwd/amdsbwd.c
@@ -255,7 +255,7 @@
 
 	if (resource_disabled("amdsbwd", 0))
 		return;
-	if (device_find_child(parent, "amdsbwd", -1) != NULL)
+	if (device_find_child(parent, "amdsbwd", DEVICE_UNIT_ANY) != NULL)
 		return;
 
 	/*
@@ -271,7 +271,8 @@
 	    pci_get_devid(smb_dev) != HYGONCZ_SMBUS_DEVID)
 		return;
 
-	child = BUS_ADD_CHILD(parent, ISA_ORDER_SPECULATIVE, "amdsbwd", DEVICE_UNIT_ANY);
+	child = BUS_ADD_CHILD(parent, ISA_ORDER_SPECULATIVE, "amdsbwd",
+	    DEVICE_UNIT_ANY);
 	if (child == NULL)
 		device_printf(parent, "add amdsbwd child failed\n");
 }
diff --git a/sys/dev/amdsmn/amdsmn.c b/sys/dev/amdsmn/amdsmn.c
--- a/sys/dev/amdsmn/amdsmn.c
+++ b/sys/dev/amdsmn/amdsmn.c
@@ -207,7 +207,7 @@
 	device_t child;
 
 	/* Make sure we're not being doubly invoked. */
-	if (device_find_child(parent, "amdsmn", -1) != NULL)
+	if (device_find_child(parent, "amdsmn", DEVICE_UNIT_ANY) != NULL)
 		return;
 	if (!amdsmn_match(parent, NULL))
 		return;
diff --git a/sys/dev/amdtemp/amdtemp.c b/sys/dev/amdtemp/amdtemp.c
--- a/sys/dev/amdtemp/amdtemp.c
+++ b/sys/dev/amdtemp/amdtemp.c
@@ -287,7 +287,7 @@
 	device_t child;
 
 	/* Make sure we're not being doubly invoked. */
-	if (device_find_child(parent, "amdtemp", -1) != NULL)
+	if (device_find_child(parent, "amdtemp", DEVICE_UNIT_ANY) != NULL)
 		return;
 
 	if (amdtemp_match(parent, NULL)) {
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
@@ -476,7 +476,7 @@
 		goto exit;
 	}
 
-	hidbus = device_add_child(sc->sc_dev, "hidbus", -1);
+	hidbus = device_add_child(sc->sc_dev, "hidbus", DEVICE_UNIT_ANY);
 	if (hidbus == NULL) {
 		device_printf(sc->sc_dev, "can't add child\n");
 		err = ENOMEM;
diff --git a/sys/dev/bhnd/bhnd_subr.c b/sys/dev/bhnd/bhnd_subr.c
--- a/sys/dev/bhnd/bhnd_subr.c
+++ b/sys/dev/bhnd/bhnd_subr.c
@@ -2170,7 +2170,7 @@
 	bus_topo_assert();
 
 	/* Look for a directly-attached NVRAM child */
-	if ((nvram = device_find_child(dev, "bhnd_nvram", -1)) != NULL)
+	if ((nvram = device_find_child(dev, "bhnd_nvram", DEVICE_UNIT_ANY)) != NULL)
 		return BHND_NVRAM_GETVAR(nvram, name, buf, size, type);
 
 	/* Try to delegate to parent */
diff --git a/sys/dev/bhnd/cores/chipc/chipc_spi.c b/sys/dev/bhnd/cores/chipc/chipc_spi.c
--- a/sys/dev/bhnd/cores/chipc/chipc_spi.c
+++ b/sys/dev/bhnd/cores/chipc/chipc_spi.c
@@ -107,7 +107,8 @@
 	 * XXX: This should be replaced with a DEVICE_IDENTIFY implementation
 	 * in chipc-specific subclasses of the mx25l and at45d drivers.
 	 */
-	if ((spibus = device_add_child(dev, "spibus", -1)) == NULL) {
+	if ((spibus = device_add_child(dev, "spibus",
+	    DEVICE_UNIT_ANY)) == NULL) {
 		device_printf(dev, "failed to add spibus\n");
 		error = ENXIO;
 		goto failed;
@@ -121,7 +122,8 @@
 	ccaps = BHND_CHIPC_GET_CAPS(device_get_parent(dev));
 	flash_name = chipc_sflash_device_name(ccaps->flash_type);
 	if (flash_name != NULL) {
-		flash_dev = BUS_ADD_CHILD(spibus, 0, flash_name, DEVICE_UNIT_ANY);
+		flash_dev = BUS_ADD_CHILD(spibus, 0, flash_name,
+		    DEVICE_UNIT_ANY);
 		if (flash_dev == NULL) {
 			device_printf(dev, "failed to add %s\n", flash_name);
 			error = ENXIO;
diff --git a/sys/dev/bwn/if_bwn_pci.c b/sys/dev/bwn/if_bwn_pci.c
--- a/sys/dev/bwn/if_bwn_pci.c
+++ b/sys/dev/bwn/if_bwn_pci.c
@@ -182,7 +182,7 @@
 	sc->quirks = ident->quirks;
 
 	/* Attach bridge device */
-	if ((error = bhndb_attach_bridge(dev, &sc->bhndb_dev, -1)))
+	if ((error = bhndb_attach_bridge(dev, &sc->bhndb_dev, DEVICE_UNIT_ANY)))
 		return (ENXIO);
 
 	/* Success */
diff --git a/sys/dev/chromebook_platform/chromebook_platform.c b/sys/dev/chromebook_platform/chromebook_platform.c
--- a/sys/dev/chromebook_platform/chromebook_platform.c
+++ b/sys/dev/chromebook_platform/chromebook_platform.c
@@ -70,7 +70,7 @@
 		return;
 
 	for (i = 0; i < nitems(slaves); i++) {
-		if (device_find_child(bus, slaves[i].name, -1) != NULL)
+		if (device_find_child(bus, slaves[i].name, DEVICE_UNIT_ANY) != NULL)
 			continue;
 		if (slaves[i].pci_id != pci_get_devid(controller))
 			continue;
diff --git a/sys/dev/coretemp/coretemp.c b/sys/dev/coretemp/coretemp.c
--- a/sys/dev/coretemp/coretemp.c
+++ b/sys/dev/coretemp/coretemp.c
@@ -112,7 +112,7 @@
 	u_int regs[4];
 
 	/* Make sure we're not being doubly invoked. */
-	if (device_find_child(parent, "coretemp", -1) != NULL)
+	if (device_find_child(parent, "coretemp", DEVICE_UNIT_ANY) != NULL)
 		return;
 
 	/* Check that CPUID 0x06 is supported and the vendor is Intel.*/
diff --git a/sys/dev/cpufreq/cpufreq_dt.c b/sys/dev/cpufreq/cpufreq_dt.c
--- a/sys/dev/cpufreq/cpufreq_dt.c
+++ b/sys/dev/cpufreq/cpufreq_dt.c
@@ -315,7 +315,7 @@
 	    !OF_hasprop(node, "operating-points-v2"))
 		return;
 
-	if (device_find_child(parent, "cpufreq_dt", -1) != NULL)
+	if (device_find_child(parent, "cpufreq_dt", DEVICE_UNIT_ANY) != NULL)
 		return;
 
 	if (BUS_ADD_CHILD(parent, 0, "cpufreq_dt", device_get_unit(parent))
diff --git a/sys/dev/cpufreq/ichss.c b/sys/dev/cpufreq/ichss.c
--- a/sys/dev/cpufreq/ichss.c
+++ b/sys/dev/cpufreq/ichss.c
@@ -147,7 +147,7 @@
 		return;
 
 	/* Avoid duplicates. */
-	if (device_find_child(parent, "ichss", -1))
+	if (device_find_child(parent, "ichss", DEVICE_UNIT_ANY))
 		return;
 
 	/*
@@ -218,13 +218,15 @@
 	 * info, let it manage things.  Also, if Enhanced SpeedStep is
 	 * available, don't attach.
 	 */
-	perf_dev = device_find_child(device_get_parent(dev), "acpi_perf", -1);
+	perf_dev = device_find_child(device_get_parent(dev), "acpi_perf",
+	    DEVICE_UNIT_ANY);
 	if (perf_dev && device_is_attached(perf_dev)) {
 		error = CPUFREQ_DRV_TYPE(perf_dev, &type);
 		if (error == 0 && (type & CPUFREQ_FLAG_INFO_ONLY) == 0)
 			return (ENXIO);
 	}
-	est_dev = device_find_child(device_get_parent(dev), "est", -1);
+	est_dev = device_find_child(device_get_parent(dev), "est",
+	    DEVICE_UNIT_ANY);
 	if (est_dev && device_is_attached(est_dev))
 		return (ENXIO);
 
diff --git a/sys/dev/cxgb/cxgb_main.c b/sys/dev/cxgb/cxgb_main.c
--- a/sys/dev/cxgb/cxgb_main.c
+++ b/sys/dev/cxgb/cxgb_main.c
@@ -622,7 +622,8 @@
 	for (i = 0; i < (sc)->params.nports; i++) {
 		struct port_info *pi;
 		
-		if ((child = device_add_child(dev, "cxgb", -1)) == NULL) {
+		if ((child = device_add_child(dev, "cxgb",
+		    DEVICE_UNIT_ANY)) == NULL) {
 			device_printf(dev, "failed to add child port\n");
 			error = EINVAL;
 			goto out;
diff --git a/sys/dev/cxgbe/crypto/t4_crypto.c b/sys/dev/cxgbe/crypto/t4_crypto.c
--- a/sys/dev/cxgbe/crypto/t4_crypto.c
+++ b/sys/dev/cxgbe/crypto/t4_crypto.c
@@ -1804,7 +1804,7 @@
 
 	sc = device_get_softc(parent);
 	if (sc->cryptocaps & FW_CAPS_CONFIG_CRYPTO_LOOKASIDE &&
-	    device_find_child(parent, "ccr", -1) == NULL)
+	    device_find_child(parent, "ccr", DEVICE_UNIT_ANY) == NULL)
 		device_add_child(parent, "ccr", DEVICE_UNIT_ANY);
 }
 
diff --git a/sys/dev/dpaa2/dpaa2_mc_acpi.c b/sys/dev/dpaa2/dpaa2_mc_acpi.c
--- a/sys/dev/dpaa2/dpaa2_mc_acpi.c
+++ b/sys/dev/dpaa2/dpaa2_mc_acpi.c
@@ -229,7 +229,7 @@
 	if ((ad = malloc(sizeof(*ad), M_DEVBUF, M_NOWAIT | M_ZERO)) == NULL)
 		return (AE_OK);
 
-	child = device_add_child(ctx->dev, "dpaa2_mac_dev", -1);
+	child = device_add_child(ctx->dev, "dpaa2_mac_dev", DEVICE_UNIT_ANY);
 	if (child == NULL) {
 		free(ad, M_DEVBUF);
 		return (AE_OK);
diff --git a/sys/dev/dpaa2/dpaa2_rc.c b/sys/dev/dpaa2/dpaa2_rc.c
--- a/sys/dev/dpaa2/dpaa2_rc.c
+++ b/sys/dev/dpaa2/dpaa2_rc.c
@@ -2905,7 +2905,7 @@
 	}
 
 	/* Add a device for the DPAA2 object. */
-	dev = device_add_child(rcdev, devclass, -1);
+	dev = device_add_child(rcdev, devclass, DEVICE_UNIT_ANY);
 	if (dev == NULL) {
 		device_printf(rcdev, "%s: failed to add a device for DPAA2 "
 		    "object: type=%s, id=%u\n", __func__, dpaa2_ttos(obj->type),
@@ -3031,7 +3031,7 @@
 	}
 
 	/* Add a device for the DPAA2 object. */
-	dev = device_add_child(rcdev, devclass, -1);
+	dev = device_add_child(rcdev, devclass, DEVICE_UNIT_ANY);
 	if (dev == NULL) {
 		device_printf(rcdev, "%s: failed to add a device for DPAA2 "
 		    "object: type=%s, id=%u\n", __func__, dpaa2_ttos(obj->type),
diff --git a/sys/dev/dpaa2/memac_mdio_acpi.c b/sys/dev/dpaa2/memac_mdio_acpi.c
--- a/sys/dev/dpaa2/memac_mdio_acpi.c
+++ b/sys/dev/dpaa2/memac_mdio_acpi.c
@@ -227,7 +227,7 @@
 	if ((ad = malloc(sizeof(*ad), M_DEVBUF, M_NOWAIT | M_ZERO)) == NULL)
 		return (AE_OK);
 
-	child = device_add_child(ctx->dev, "memacphy_acpi", -1);
+	child = device_add_child(ctx->dev, "memacphy_acpi", DEVICE_UNIT_ANY);
 	if (child == NULL) {
 		free(ad, M_DEVBUF);
 		return (AE_OK);
diff --git a/sys/dev/efidev/efirtc.c b/sys/dev/efidev/efirtc.c
--- a/sys/dev/efidev/efirtc.c
+++ b/sys/dev/efidev/efirtc.c
@@ -52,9 +52,9 @@
 	/* Don't add the driver unless we have working runtime services. */
 	if (efi_rt_ok() != 0)
 		return;
-	if (device_find_child(parent, "efirtc", -1) != NULL)
+	if (device_find_child(parent, "efirtc", DEVICE_UNIT_ANY) != NULL)
 		return;
-	if (BUS_ADD_CHILD(parent, 0, "efirtc", -1) == NULL)
+	if (BUS_ADD_CHILD(parent, 0, "efirtc", DEVICE_UNIT_ANY) == NULL)
 		device_printf(parent, "add child failed\n");
 }
 
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
@@ -205,7 +205,7 @@
 e6000sw_identify(driver_t *driver, device_t parent)
 {
 
-	if (device_find_child(parent, "e6000sw", -1) == NULL)
+	if (device_find_child(parent, "e6000sw", DEVICE_UNIT_ANY) == NULL)
 		BUS_ADD_CHILD(parent, 0, "e6000sw", DEVICE_UNIT_ANY);
 }
 
diff --git a/sys/dev/etherswitch/etherswitch.c b/sys/dev/etherswitch/etherswitch.c
--- a/sys/dev/etherswitch/etherswitch.c
+++ b/sys/dev/etherswitch/etherswitch.c
@@ -82,7 +82,7 @@
 static void
 etherswitch_identify(driver_t *driver, device_t parent)
 {
-	if (device_find_child(parent, "etherswitch", -1) == NULL)
+	if (device_find_child(parent, "etherswitch", DEVICE_UNIT_ANY) == NULL)
 		BUS_ADD_CHILD(parent, 0, "etherswitch", DEVICE_UNIT_ANY);
 }
 
diff --git a/sys/dev/etherswitch/ip17x/ip17x.c b/sys/dev/etherswitch/ip17x/ip17x.c
--- a/sys/dev/etherswitch/ip17x/ip17x.c
+++ b/sys/dev/etherswitch/ip17x/ip17x.c
@@ -83,7 +83,7 @@
 static void
 ip17x_identify(driver_t *driver, device_t parent)
 {
-	if (device_find_child(parent, "ip17x", -1) == NULL)
+	if (device_find_child(parent, "ip17x", DEVICE_UNIT_ANY) == NULL)
 	    BUS_ADD_CHILD(parent, 0, "ip17x", DEVICE_UNIT_ANY);
 }
 
diff --git a/sys/dev/etherswitch/miiproxy.c b/sys/dev/etherswitch/miiproxy.c
--- a/sys/dev/etherswitch/miiproxy.c
+++ b/sys/dev/etherswitch/miiproxy.c
@@ -331,7 +331,7 @@
 static void
 mdioproxy_identify(driver_t *driver, device_t parent)
 {
-	if (device_find_child(parent, driver->name, -1) == NULL) {
+	if (device_find_child(parent, driver->name, DEVICE_UNIT_ANY) == NULL) {
 		BUS_ADD_CHILD(parent, 0, driver->name, DEVICE_UNIT_ANY);
 	}
 }
diff --git a/sys/dev/etherswitch/rtl8366/rtl8366rb.c b/sys/dev/etherswitch/rtl8366/rtl8366rb.c
--- a/sys/dev/etherswitch/rtl8366/rtl8366rb.c
+++ b/sys/dev/etherswitch/rtl8366/rtl8366rb.c
@@ -133,7 +133,7 @@
 	device_t child;
 	struct iicbus_ivar *devi;
 
-	if (device_find_child(parent, "rtl8366rb", -1) == NULL) {
+	if (device_find_child(parent, "rtl8366rb", DEVICE_UNIT_ANY) == NULL) {
 		child = BUS_ADD_CHILD(parent, 0, "rtl8366rb", DEVICE_UNIT_ANY);
 		devi = IICBUS_IVAR(child);
 		devi->addr = RTL8366_IIC_ADDR;
diff --git a/sys/dev/firewire/sbp.c b/sys/dev/firewire/sbp.c
--- a/sys/dev/firewire/sbp.c
+++ b/sys/dev/firewire/sbp.c
@@ -303,7 +303,7 @@
 	printf("sbp_identify\n");
 END_DEBUG
 
-	if (device_find_child(parent, "sbp", -1) == NULL)
+	if (device_find_child(parent, "sbp", DEVICE_UNIT_ANY) == NULL)
 		BUS_ADD_CHILD(parent, 0, "sbp", DEVICE_UNIT_ANY);
 }
 
diff --git a/sys/dev/glxiic/glxiic.c b/sys/dev/glxiic/glxiic.c
--- a/sys/dev/glxiic/glxiic.c
+++ b/sys/dev/glxiic/glxiic.c
@@ -284,11 +284,11 @@
 {
 
 	/* Prevent child from being added more than once. */
-	if (device_find_child(parent, driver->name, -1) != NULL)
+	if (device_find_child(parent, driver->name, DEVICE_UNIT_ANY) != NULL)
 		return;
 
 	if (pci_get_devid(parent) == GLXIIC_CS5536_DEV_ID) {
-		if (device_add_child(parent, driver->name, -1) == NULL)
+		if (device_add_child(parent, driver->name, DEVICE_UNIT_ANY) == NULL)
 			device_printf(parent, "Could not add glxiic child\n");
 	}
 }
@@ -390,7 +390,8 @@
 		goto out;
 	}
 
-	if ((sc->iicbus = device_add_child(dev, "iicbus", -1)) == NULL) {
+	if ((sc->iicbus = device_add_child(dev, "iicbus",
+	    DEVICE_UNIT_ANY)) == NULL) {
 		device_printf(dev, "Could not allocate iicbus instance\n");
 		error = ENXIO;
 		goto out;
diff --git a/sys/dev/gpio/gpiobus.c b/sys/dev/gpio/gpiobus.c
--- a/sys/dev/gpio/gpiobus.c
+++ b/sys/dev/gpio/gpiobus.c
@@ -300,7 +300,7 @@
 	busdev = device_add_child(dev, "gpiobus", DEVICE_UNIT_ANY);
 	if (busdev == NULL)
 		return (NULL);
-	if (device_add_child(dev, "gpioc", -1) == NULL) {
+	if (device_add_child(dev, "gpioc", DEVICE_UNIT_ANY) == NULL) {
 		device_delete_child(dev, busdev);
 		return (NULL);
 	}
diff --git a/sys/dev/hid/hidraw.c b/sys/dev/hid/hidraw.c
--- a/sys/dev/hid/hidraw.c
+++ b/sys/dev/hid/hidraw.c
@@ -183,7 +183,7 @@
 {
 	device_t child;
 
-	if (device_find_child(parent, "hidraw", -1) == NULL) {
+	if (device_find_child(parent, "hidraw", DEVICE_UNIT_ANY) == NULL) {
 		child = BUS_ADD_CHILD(parent, 0, "hidraw",
 		    device_get_unit(parent));
 		if (child != 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
@@ -436,7 +436,7 @@
 		ret = ENODEV;
 		goto out;
 	}
-	child = device_add_child(sc->dev, "hidbus", -1);
+	child = device_add_child(sc->dev, "hidbus", DEVICE_UNIT_ANY);
 	if (child == NULL) {
 		device_printf(sc->dev, "failed to add hidbus\n");
 		ret = ENOMEM;
diff --git a/sys/dev/hyperv/vmbus/vmbus_et.c b/sys/dev/hyperv/vmbus/vmbus_et.c
--- a/sys/dev/hyperv/vmbus/vmbus_et.c
+++ b/sys/dev/hyperv/vmbus/vmbus_et.c
@@ -127,7 +127,7 @@
 vmbus_et_identify(driver_t *driver, device_t parent)
 {
 	if (device_get_unit(parent) != 0 ||
-	    device_find_child(parent, VMBUS_ET_NAME, -1) != NULL ||
+	    device_find_child(parent, VMBUS_ET_NAME, DEVICE_UNIT_ANY) != NULL ||
 	    (hyperv_features & CPUID_HV_ET_MASK) != CPUID_HV_ET_MASK ||
 	    hyperv_tc64 == NULL)
 		return;
diff --git a/sys/dev/ichsmb/ichsmb.c b/sys/dev/ichsmb/ichsmb.c
--- a/sys/dev/ichsmb/ichsmb.c
+++ b/sys/dev/ichsmb/ichsmb.c
@@ -112,7 +112,8 @@
 	mtx_init(&sc->mutex, device_get_nameunit(dev), "ichsmb", MTX_DEF);
 
 	/* Add child: an instance of the "smbus" device */
-	if ((sc->smb = device_add_child(dev, DRIVER_SMBUS, -1)) == NULL) {
+	if ((sc->smb = device_add_child(dev, DRIVER_SMBUS,
+	    DEVICE_UNIT_ANY)) == NULL) {
 		device_printf(dev, "no \"%s\" child found\n", DRIVER_SMBUS);
 		error = ENXIO;
 		goto fail;
diff --git a/sys/dev/iicbus/controller/cadence/cdnc_i2c.c b/sys/dev/iicbus/controller/cadence/cdnc_i2c.c
--- a/sys/dev/iicbus/controller/cadence/cdnc_i2c.c
+++ b/sys/dev/iicbus/controller/cadence/cdnc_i2c.c
@@ -612,7 +612,7 @@
 		return (err);
 	}
 
-	sc->iicbus = device_add_child(dev, "iicbus", -1);
+	sc->iicbus = device_add_child(dev, "iicbus", DEVICE_UNIT_ANY);
 
 	cdnc_i2c_add_sysctls(dev);
 
diff --git a/sys/dev/iicbus/controller/twsi/twsi.c b/sys/dev/iicbus/controller/twsi/twsi.c
--- a/sys/dev/iicbus/controller/twsi/twsi.c
+++ b/sys/dev/iicbus/controller/twsi/twsi.c
@@ -812,7 +812,8 @@
 	    &sc->debug, 0, "Set debug level (zero to disable)");
 
 	/* Attach the iicbus. */
-	if ((sc->iicbus = device_add_child(dev, "iicbus", -1)) == NULL) {
+	if ((sc->iicbus = device_add_child(dev, "iicbus",
+	    DEVICE_UNIT_ANY)) == NULL) {
 		device_printf(dev, "could not allocate iicbus instance\n");
 		twsi_detach(dev);
 		return (ENXIO);
diff --git a/sys/dev/iicbus/iic.c b/sys/dev/iicbus/iic.c
--- a/sys/dev/iicbus/iic.c
+++ b/sys/dev/iicbus/iic.c
@@ -133,7 +133,7 @@
 iic_identify(driver_t *driver, device_t parent)
 {
 
-	if (device_find_child(parent, "iic", -1) == NULL)
+	if (device_find_child(parent, "iic", DEVICE_UNIT_ANY) == NULL)
 		BUS_ADD_CHILD(parent, 0, "iic", DEVICE_UNIT_ANY);
 }
 
diff --git a/sys/dev/iicbus/iicsmb.c b/sys/dev/iicbus/iicsmb.c
--- a/sys/dev/iicbus/iicsmb.c
+++ b/sys/dev/iicbus/iicsmb.c
@@ -134,7 +134,7 @@
 iicsmb_identify(driver_t *driver, device_t parent)
 {
 
-	if (device_find_child(parent, "iicsmb", -1) == NULL)
+	if (device_find_child(parent, "iicsmb", DEVICE_UNIT_ANY) == NULL)
 		BUS_ADD_CHILD(parent, 0, "iicsmb", DEVICE_UNIT_ANY);
 }
 
diff --git a/sys/dev/ipmi/ipmi_isa.c b/sys/dev/ipmi/ipmi_isa.c
--- a/sys/dev/ipmi/ipmi_isa.c
+++ b/sys/dev/ipmi/ipmi_isa.c
@@ -57,7 +57,7 @@
 	uint32_t devid;
 
 	if (ipmi_smbios_identify(&info) && info.iface_type != SSIF_MODE &&
-	    device_find_child(parent, "ipmi", -1) == NULL) {
+	    device_find_child(parent, "ipmi", DEVICE_UNIT_ANY) == NULL) {
 		/*
 		 * XXX: Hack alert.  On some broken systems, the IPMI
 		 * interface is described via SMBIOS, but the actual
diff --git a/sys/dev/ipmi/ipmi_smbus.c b/sys/dev/ipmi/ipmi_smbus.c
--- a/sys/dev/ipmi/ipmi_smbus.c
+++ b/sys/dev/ipmi/ipmi_smbus.c
@@ -59,7 +59,7 @@
 	struct ipmi_get_info info;
 
 	if (ipmi_smbios_identify(&info) && info.iface_type == SSIF_MODE &&
-	    device_find_child(parent, "ipmi", -1) == NULL)
+	    device_find_child(parent, "ipmi", DEVICE_UNIT_ANY) == NULL)
 		BUS_ADD_CHILD(parent, 0, "ipmi", DEVICE_UNIT_ANY);
 }
 
diff --git a/sys/dev/isl/isl.c b/sys/dev/isl/isl.c
--- a/sys/dev/isl/isl.c
+++ b/sys/dev/isl/isl.c
@@ -149,7 +149,7 @@
 isl_identify(driver_t *driver, device_t parent)
 {
 
-	if (device_find_child(parent, "asl", -1)) {
+	if (device_find_child(parent, "asl", DEVICE_UNIT_ANY)) {
 		if (bootverbose)
 			printf("asl: device(s) already created\n");
 		return;
diff --git a/sys/dev/ismt/ismt.c b/sys/dev/ismt/ismt.c
--- a/sys/dev/ismt/ismt.c
+++ b/sys/dev/ismt/ismt.c
@@ -586,7 +586,8 @@
 	sc->pcidev = dev;
 	pci_enable_busmaster(dev);
 
-	if ((sc->smbdev = device_add_child(dev, "smbus", -1)) == NULL) {
+	if ((sc->smbdev = device_add_child(dev, "smbus",
+	    DEVICE_UNIT_ANY)) == NULL) {
 		device_printf(dev, "no smbus child found\n");
 		err = ENXIO;
 		goto fail;
diff --git a/sys/dev/kvm_clock/kvm_clock.c b/sys/dev/kvm_clock/kvm_clock.c
--- a/sys/dev/kvm_clock/kvm_clock.c
+++ b/sys/dev/kvm_clock/kvm_clock.c
@@ -141,7 +141,7 @@
 	if ((regs[0] &
 	    (KVM_FEATURE_CLOCKSOURCE2 | KVM_FEATURE_CLOCKSOURCE)) == 0)
 		return;
-	if (device_find_child(parent, KVM_CLOCK_DEVNAME, -1))
+	if (device_find_child(parent, KVM_CLOCK_DEVNAME, DEVICE_UNIT_ANY))
 		return;
 	BUS_ADD_CHILD(parent, 0, KVM_CLOCK_DEVNAME, 0);
 }
diff --git a/sys/dev/mdio/mdio.c b/sys/dev/mdio/mdio.c
--- a/sys/dev/mdio/mdio.c
+++ b/sys/dev/mdio/mdio.c
@@ -37,7 +37,7 @@
 mdio_identify(driver_t *driver, device_t parent)
 {
 
-	if (device_find_child(parent, mdio_driver.name, -1) == NULL)
+	if (device_find_child(parent, mdio_driver.name, DEVICE_UNIT_ANY) == NULL)
 		BUS_ADD_CHILD(parent, 0, mdio_driver.name, DEVICE_UNIT_ANY);
 }
 
diff --git a/sys/dev/mfi/mfi.c b/sys/dev/mfi/mfi.c
--- a/sys/dev/mfi/mfi.c
+++ b/sys/dev/mfi/mfi.c
@@ -1922,7 +1922,8 @@
 
 	mtx_unlock(&sc->mfi_io_lock);
 	bus_topo_lock();
-	if ((child = device_add_child(sc->mfi_dev, "mfid", -1)) == NULL) {
+	if ((child = device_add_child(sc->mfi_dev, "mfid",
+	    DEVICE_UNIT_ANY)) == NULL) {
 		device_printf(sc->mfi_dev, "Failed to add logical disk\n");
 		free(ld_info, M_MFIBUF);
 		bus_topo_unlock();
@@ -2010,7 +2011,8 @@
 
 	mtx_unlock(&sc->mfi_io_lock);
 	bus_topo_lock();
-	if ((child = device_add_child(sc->mfi_dev, "mfisyspd", -1)) == NULL) {
+	if ((child = device_add_child(sc->mfi_dev, "mfisyspd",
+	    DEVICE_UNIT_ANY)) == NULL) {
 		device_printf(sc->mfi_dev, "Failed to add system pd\n");
 		free(pd_info, M_MFIBUF);
 		bus_topo_unlock();
diff --git a/sys/dev/mfi/mfi_cam.c b/sys/dev/mfi/mfi_cam.c
--- a/sys/dev/mfi/mfi_cam.c
+++ b/sys/dev/mfi/mfi_cam.c
@@ -298,7 +298,7 @@
 	device_t mfip_dev;
 
 	bus_topo_lock();
-	mfip_dev = device_find_child(sc->mfi_dev, "mfip", -1);
+	mfip_dev = device_find_child(sc->mfi_dev, "mfip", DEVICE_UNIT_ANY);
 	bus_topo_unlock();
 	if (mfip_dev == NULL) {
 		device_printf(sc->mfi_dev, "Couldn't find mfip child device!\n");
diff --git a/sys/dev/mmcnull/mmcnull.c b/sys/dev/mmcnull/mmcnull.c
--- a/sys/dev/mmcnull/mmcnull.c
+++ b/sys/dev/mmcnull/mmcnull.c
@@ -77,7 +77,7 @@
 		return;
 
 	/* Avoid duplicates. */
-	if (device_find_child(parent, "mmcnull", -1))
+	if (device_find_child(parent, "mmcnull", DEVICE_UNIT_ANY))
 		return;
 
 	child = BUS_ADD_CHILD(parent, 20, "mmcnull", 0);
diff --git a/sys/dev/nvdimm/nvdimm_e820.c b/sys/dev/nvdimm/nvdimm_e820.c
--- a/sys/dev/nvdimm/nvdimm_e820.c
+++ b/sys/dev/nvdimm/nvdimm_e820.c
@@ -261,7 +261,7 @@
 	if (resource_disabled(driver->name, 0))
 		return;
 	/* Just create a single instance of the fake bus. */
-	if (device_find_child(parent, driver->name, -1) != NULL)
+	if (device_find_child(parent, driver->name, DEVICE_UNIT_ANY) != NULL)
 		return;
 
 	smapbase = (const void *)preload_search_info(preload_kmdp,
diff --git a/sys/dev/nvmf/host/nvmf_ctldev.c b/sys/dev/nvmf/host/nvmf_ctldev.c
--- a/sys/dev/nvmf/host/nvmf_ctldev.c
+++ b/sys/dev/nvmf/host/nvmf_ctldev.c
@@ -29,7 +29,7 @@
 		return (error);
 
 	bus_topo_lock();
-	dev = device_add_child(root_bus, "nvme", -1);
+	dev = device_add_child(root_bus, "nvme", DEVICE_UNIT_ANY);
 	if (dev == NULL) {
 		bus_topo_unlock();
 		error = ENXIO;
diff --git a/sys/dev/p2sb/lewisburg_gpiocm.c b/sys/dev/p2sb/lewisburg_gpiocm.c
--- a/sys/dev/p2sb/lewisburg_gpiocm.c
+++ b/sys/dev/p2sb/lewisburg_gpiocm.c
@@ -315,7 +315,7 @@
 		group->npins = npins < MAX_PAD_PER_GROUP ? npins :
 			MAX_PAD_PER_GROUP;
 		npins -= group->npins;
-		group->dev = device_add_child(dev, "gpio", -1);
+		group->dev = device_add_child(dev, "gpio", DEVICE_UNIT_ANY);
 	}
 	sc->community->ngroups = i;
 	bus_attach_children(dev);
diff --git a/sys/dev/pcf/pcf_isa.c b/sys/dev/pcf/pcf_isa.c
--- a/sys/dev/pcf/pcf_isa.c
+++ b/sys/dev/pcf/pcf_isa.c
@@ -160,7 +160,7 @@
 		}
 	}
 
-	if ((sc->iicbus = device_add_child(dev, "iicbus", -1)) == NULL)
+	if ((sc->iicbus = device_add_child(dev, "iicbus", DEVICE_UNIT_ANY)) == NULL)
 		device_printf(dev, "could not allocate iicbus instance\n");
 
 	/* probe and attach the iicbus */
diff --git a/sys/dev/pci/pci_host_generic_den0115.c b/sys/dev/pci/pci_host_generic_den0115.c
--- a/sys/dev/pci/pci_host_generic_den0115.c
+++ b/sys/dev/pci/pci_host_generic_den0115.c
@@ -193,7 +193,7 @@
 		sc->base.bus_end = MIN(sc->base.bus_end, end);
 	}
 
-	device_add_child(dev, "pci", -1);
+	device_add_child(dev, "pci", DEVICE_UNIT_ANY);
 	bus_attach_children(dev);
 	return (0);
 }
diff --git a/sys/dev/ppbus/if_plip.c b/sys/dev/ppbus/if_plip.c
--- a/sys/dev/ppbus/if_plip.c
+++ b/sys/dev/ppbus/if_plip.c
@@ -214,7 +214,7 @@
 {
 	device_t dev;
 
-	dev = device_find_child(parent, "plip", -1);
+	dev = device_find_child(parent, "plip", DEVICE_UNIT_ANY);
 	if (!dev)
 		BUS_ADD_CHILD(parent, 0, "plip", DEVICE_UNIT_ANY);
 }
diff --git a/sys/dev/ppbus/lpbb.c b/sys/dev/ppbus/lpbb.c
--- a/sys/dev/ppbus/lpbb.c
+++ b/sys/dev/ppbus/lpbb.c
@@ -61,7 +61,7 @@
 
 	device_t dev;
 
-	dev = device_find_child(parent, "lpbb", -1);
+	dev = device_find_child(parent, "lpbb", DEVICE_UNIT_ANY);
 	if (!dev)
 		BUS_ADD_CHILD(parent, 0, "lpbb", DEVICE_UNIT_ANY);
 }
diff --git a/sys/dev/ppbus/lpt.c b/sys/dev/ppbus/lpt.c
--- a/sys/dev/ppbus/lpt.c
+++ b/sys/dev/ppbus/lpt.c
@@ -336,7 +336,7 @@
 
 	device_t dev;
 
-	dev = device_find_child(parent, LPT_NAME, -1);
+	dev = device_find_child(parent, LPT_NAME, DEVICE_UNIT_ANY);
 	if (!dev)
 		BUS_ADD_CHILD(parent, 0, LPT_NAME, DEVICE_UNIT_ANY);
 }
diff --git a/sys/dev/ppbus/pcfclock.c b/sys/dev/ppbus/pcfclock.c
--- a/sys/dev/ppbus/pcfclock.c
+++ b/sys/dev/ppbus/pcfclock.c
@@ -111,7 +111,7 @@
 
 	device_t dev;
 
-	dev = device_find_child(parent, PCFCLOCK_NAME, -1);
+	dev = device_find_child(parent, PCFCLOCK_NAME, DEVICE_UNIT_ANY);
 	if (!dev)
 		BUS_ADD_CHILD(parent, 0, PCFCLOCK_NAME, DEVICE_UNIT_ANY);
 }
diff --git a/sys/dev/ppbus/ppi.c b/sys/dev/ppbus/ppi.c
--- a/sys/dev/ppbus/ppi.c
+++ b/sys/dev/ppbus/ppi.c
@@ -135,7 +135,7 @@
 
 	device_t dev;
 
-	dev = device_find_child(parent, "ppi", -1);
+	dev = device_find_child(parent, "ppi", DEVICE_UNIT_ANY);
 	if (!dev)
 		BUS_ADD_CHILD(parent, 0, "ppi", DEVICE_UNIT_ANY);
 }
diff --git a/sys/dev/ppbus/pps.c b/sys/dev/ppbus/pps.c
--- a/sys/dev/ppbus/pps.c
+++ b/sys/dev/ppbus/pps.c
@@ -76,7 +76,7 @@
 
 	device_t dev;
 
-	dev = device_find_child(parent, PPS_NAME, -1);
+	dev = device_find_child(parent, PPS_NAME, DEVICE_UNIT_ANY);
 	if (!dev)
 		BUS_ADD_CHILD(parent, 0, PPS_NAME, DEVICE_UNIT_ANY);
 }
diff --git a/sys/dev/psci/smccc_errata.c b/sys/dev/psci/smccc_errata.c
--- a/sys/dev/psci/smccc_errata.c
+++ b/sys/dev/psci/smccc_errata.c
@@ -78,7 +78,7 @@
 	if (version < EM_VERSION_MIN)
 		return;
 
-	if (BUS_ADD_CHILD(parent, 0, "errata", -1) == NULL)
+	if (BUS_ADD_CHILD(parent, 0, "errata", DEVICE_UNIT_ANY) == NULL)
 		device_printf(parent, "add errata child failed\n");
 }
 
diff --git a/sys/dev/psci/smccc_trng.c b/sys/dev/psci/smccc_trng.c
--- a/sys/dev/psci/smccc_trng.c
+++ b/sys/dev/psci/smccc_trng.c
@@ -78,7 +78,7 @@
 	if (version < TRNG_VERSION_MIN)
 		return;
 
-	if (BUS_ADD_CHILD(parent, 0, "trng", -1) == NULL)
+	if (BUS_ADD_CHILD(parent, 0, "trng", DEVICE_UNIT_ANY) == NULL)
 		device_printf(parent, "add TRNG child failed\n");
 }
 
diff --git a/sys/dev/pwm/ofw_pwmbus.c b/sys/dev/pwm/ofw_pwmbus.c
--- a/sys/dev/pwm/ofw_pwmbus.c
+++ b/sys/dev/pwm/ofw_pwmbus.c
@@ -150,7 +150,8 @@
 		if (chan >= sc->base.nchannels)
 			continue;
 
-		if ((child = ofw_pwmbus_add_child(dev, 0, NULL, -1)) == NULL)
+		if ((child = ofw_pwmbus_add_child(dev, 0, NULL,
+		    DEVICE_UNIT_ANY)) == NULL)
 			continue;
 
 		ivars = device_get_ivars(child);
@@ -173,7 +174,8 @@
 	 */
 	if (!any_children) {
 		for (chan = 0; chan < sc->base.nchannels; ++chan) {
-			child = ofw_pwmbus_add_child(dev, 0, "pwmc", -1);
+			child = ofw_pwmbus_add_child(dev, 0, "pwmc",
+			    DEVICE_UNIT_ANY);
 			if (child == NULL) {
 				device_printf(dev, "failed to add pwmc child "
 				    " device for channel %u\n", chan);
diff --git a/sys/dev/qat/qat/qat_ocf.c b/sys/dev/qat/qat/qat_ocf.c
--- a/sys/dev/qat/qat/qat_ocf.c
+++ b/sys/dev/qat/qat/qat_ocf.c
@@ -941,8 +941,8 @@
 static void
 qat_ocf_identify(driver_t *drv, device_t parent)
 {
-	if (device_find_child(parent, "qat_ocf", -1) == NULL &&
-	    BUS_ADD_CHILD(parent, 200, "qat_ocf", -1) == 0)
+	if (device_find_child(parent, "qat_ocf", DEVICE_UNIT_ANY) == NULL &&
+	    BUS_ADD_CHILD(parent, 200, "qat_ocf", DEVICE_UNIT_ANY) == 0)
 		device_printf(parent, "qat_ocf: could not attach!");
 }
 
diff --git a/sys/dev/qcom_qup/qcom_spi.c b/sys/dev/qcom_qup/qcom_spi.c
--- a/sys/dev/qcom_qup/qcom_spi.c
+++ b/sys/dev/qcom_qup/qcom_spi.c
@@ -420,7 +420,7 @@
 	}
 	QCOM_SPI_UNLOCK(sc);
 
-	sc->spibus = device_add_child(dev, "spibus", -1);
+	sc->spibus = device_add_child(dev, "spibus", DEVICE_UNIT_ANY);
 
 	/* We're done, so shut down the interface clock for now */
 	device_printf(dev, "DONE: shutting down interface clock for now\n");
diff --git a/sys/dev/sdio/sdiob.c b/sys/dev/sdio/sdiob.c
--- a/sys/dev/sdio/sdiob.c
+++ b/sys/dev/sdio/sdiob.c
@@ -923,7 +923,7 @@
 	    __func__, sc, sc->periph, sc->periph->sim));
 
 	if (sc->dev == NULL)
-		sc->dev = BUS_ADD_CHILD(pdev, 0, SDIOB_NAME_S, -1);
+		sc->dev = BUS_ADD_CHILD(pdev, 0, SDIOB_NAME_S, DEVICE_UNIT_ANY);
 	if (sc->dev == NULL)
 		return (ENXIO);
 	device_set_softc(sc->dev, sc);
diff --git a/sys/dev/smbus/smb.c b/sys/dev/smbus/smb.c
--- a/sys/dev/smbus/smb.c
+++ b/sys/dev/smbus/smb.c
@@ -126,7 +126,7 @@
 smb_identify(driver_t *driver, device_t parent)
 {
 
-	if (device_find_child(parent, "smb", -1) == NULL)
+	if (device_find_child(parent, "smb", DEVICE_UNIT_ANY) == NULL)
 		BUS_ADD_CHILD(parent, 0, "smb", DEVICE_UNIT_ANY);
 }
 
diff --git a/sys/dev/sound/dummy.c b/sys/dev/sound/dummy.c
--- a/sys/dev/sound/dummy.c
+++ b/sys/dev/sound/dummy.c
@@ -296,9 +296,9 @@
 static void
 dummy_identify(driver_t *driver, device_t parent)
 {
-	if (device_find_child(parent, driver->name, -1) != NULL)
+	if (device_find_child(parent, driver->name, DEVICE_UNIT_ANY) != NULL)
 		return;
-	if (BUS_ADD_CHILD(parent, 0, driver->name, -1) == NULL)
+	if (BUS_ADD_CHILD(parent, 0, driver->name, DEVICE_UNIT_ANY) == NULL)
 		device_printf(parent, "add child failed\n");
 }
 
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
@@ -890,7 +890,7 @@
 		scp = malloc(sizeof(struct sc_pcminfo), M_DEVBUF, M_WAITOK | M_ZERO);
 		scp->hc = &chan_map[i];
 		scp->sc = sc;
-		scp->dev = device_add_child(dev, "pcm", -1);
+		scp->dev = device_add_child(dev, "pcm", DEVICE_UNIT_ANY);
 		device_set_ivars(scp->dev, scp);
 	}
 
diff --git a/sys/dev/spibus/acpi_spibus.c b/sys/dev/spibus/acpi_spibus.c
--- a/sys/dev/spibus/acpi_spibus.c
+++ b/sys/dev/spibus/acpi_spibus.c
@@ -302,7 +302,7 @@
 	if (acpi_spibus_delete_acpi_child(handle) != 0)
 		return (AE_OK);
 
-	child = BUS_ADD_CHILD(spibus, 0, NULL, -1);
+	child = BUS_ADD_CHILD(spibus, 0, NULL, DEVICE_UNIT_ANY);
 	if (child == NULL) {
 		device_printf(spibus, "add child failed\n");
 		return (AE_OK);
diff --git a/sys/dev/superio/superio.c b/sys/dev/superio/superio.c
--- a/sys/dev/superio/superio.c
+++ b/sys/dev/superio/superio.c
@@ -633,7 +633,7 @@
 	 * Those could be created via isa hints or if this
 	 * driver is loaded, unloaded and then loaded again.
 	 */
-	if (device_find_child(parent, "superio", -1)) {
+	if (device_find_child(parent, "superio", DEVICE_UNIT_ANY)) {
 		if (bootverbose)
 			printf("superio: device(s) already created\n");
 		return;
diff --git a/sys/dev/usb/misc/i2ctinyusb.c b/sys/dev/usb/misc/i2ctinyusb.c
--- a/sys/dev/usb/misc/i2ctinyusb.c
+++ b/sys/dev/usb/misc/i2ctinyusb.c
@@ -167,7 +167,7 @@
 	sc->sc_udev = uaa->device;
 	mtx_init(&sc->sc_mtx, "i2ctinyusb lock", NULL, MTX_DEF | MTX_RECURSE);
 
-	sc->iicbus_dev = device_add_child(dev, "iicbus", -1);
+	sc->iicbus_dev = device_add_child(dev, "iicbus", DEVICE_UNIT_ANY);
 	if (sc->iicbus_dev == NULL) {
 		device_printf(dev, "iicbus creation failed\n");
 		err = ENXIO;
diff --git a/sys/dev/viapm/viapm.c b/sys/dev/viapm/viapm.c
--- a/sys/dev/viapm/viapm.c
+++ b/sys/dev/viapm/viapm.c
@@ -423,7 +423,7 @@
 	VIAPM_OUTB(GPIO_DIR, VIAPM_INB(GPIO_DIR) | VIAPM_SCL | VIAPM_SDA);
 
 	/* add generic bit-banging code */
-	if (!(viapm->iicbb = device_add_child(dev, "iicbb", -1)))
+	if (!(viapm->iicbb = device_add_child(dev, "iicbb", DEVICE_UNIT_ANY)))
 		goto error;
 
 	bus_attach_children(dev);
diff --git a/sys/dev/viawd/viawd.c b/sys/dev/viawd/viawd.c
--- a/sys/dev/viawd/viawd.c
+++ b/sys/dev/viawd/viawd.c
@@ -125,7 +125,7 @@
 	if (viawd_find(parent) == NULL)
 		return;
 
-	if (device_find_child(parent, driver->name, -1) == NULL)
+	if (device_find_child(parent, driver->name, DEVICE_UNIT_ANY) == NULL)
 		BUS_ADD_CHILD(parent, 0, driver->name, 0);
 }
 
diff --git a/sys/dev/virtio/mmio/virtio_mmio.c b/sys/dev/virtio/mmio/virtio_mmio.c
--- a/sys/dev/virtio/mmio/virtio_mmio.c
+++ b/sys/dev/virtio/mmio/virtio_mmio.c
@@ -275,7 +275,7 @@
 	/* Tell the host we've noticed this device. */
 	vtmmio_set_status(dev, VIRTIO_CONFIG_STATUS_ACK);
 
-	if ((child = device_add_child(dev, NULL, -1)) == NULL) {
+	if ((child = device_add_child(dev, NULL, DEVICE_UNIT_ANY)) == NULL) {
 		device_printf(dev, "Cannot create child device.\n");
 		vtmmio_set_status(dev, VIRTIO_CONFIG_STATUS_FAILED);
 		vtmmio_detach(dev);
diff --git a/sys/isa/isahint.c b/sys/isa/isahint.c
--- a/sys/isa/isahint.c
+++ b/sys/isa/isahint.c
@@ -45,7 +45,8 @@
 	/* device-specific flag overrides any wildcard */
 	sensitive = 0;
 	if (resource_int_value(name, unit, "sensitive", &sensitive) != 0)
-		resource_int_value(name, -1, "sensitive", &sensitive);
+		resource_int_value(name, DEVICE_UNIT_ANY, "sensitive",
+		    &sensitive);
 
 	if (sensitive)
 		order = ISA_ORDER_SENSITIVE;
diff --git a/sys/kern/kern_cpu.c b/sys/kern/kern_cpu.c
--- a/sys/kern/kern_cpu.c
+++ b/sys/kern/kern_cpu.c
@@ -1101,7 +1101,7 @@
 	 * must offer the same levels and be switched at the same time.
 	 */
 	cpu_dev = device_get_parent(dev);
-	if ((cf_dev = device_find_child(cpu_dev, "cpufreq", -1))) {
+	if ((cf_dev = device_find_child(cpu_dev, "cpufreq", DEVICE_UNIT_ANY))) {
 		sc = device_get_softc(cf_dev);
 		sc->max_mhz = CPUFREQ_VAL_UNKNOWN;
 		MPASS(sc->cf_drv_dev != NULL);
@@ -1135,7 +1135,8 @@
 	 * device as well.  We identify cpufreq children by calling a method
 	 * they support.
 	 */
-	cf_dev = device_find_child(device_get_parent(dev), "cpufreq", -1);
+	cf_dev = device_find_child(device_get_parent(dev), "cpufreq",
+	    DEVICE_UNIT_ANY);
 	if (cf_dev == NULL) {
 		device_printf(dev,
 	"warning: cpufreq_unregister called with no cpufreq device active\n");
diff --git a/sys/opencrypto/cryptosoft.c b/sys/opencrypto/cryptosoft.c
--- a/sys/opencrypto/cryptosoft.c
+++ b/sys/opencrypto/cryptosoft.c
@@ -1686,7 +1686,7 @@
 swcr_identify(driver_t *drv, device_t parent)
 {
 	/* NB: order 10 is so we get attached after h/w devices */
-	if (device_find_child(parent, "cryptosoft", -1) == NULL &&
+	if (device_find_child(parent, "cryptosoft", DEVICE_UNIT_ANY) == NULL &&
 	    BUS_ADD_CHILD(parent, 10, "cryptosoft", 0) == 0)
 		panic("cryptosoft: could not attach");
 }
diff --git a/sys/powerpc/cpufreq/dfs.c b/sys/powerpc/cpufreq/dfs.c
--- a/sys/powerpc/cpufreq/dfs.c
+++ b/sys/powerpc/cpufreq/dfs.c
@@ -94,14 +94,14 @@
 	}
 
 	/* Make sure we're not being doubly invoked. */
-	if (device_find_child(parent, "dfs", -1) != NULL)
+	if (device_find_child(parent, "dfs", DEVICE_UNIT_ANY) != NULL)
 		return;
 
 	/*
 	 * We attach a child for every CPU since settings need to
 	 * be performed on every CPU in the SMP case.
 	 */
-	if (BUS_ADD_CHILD(parent, 10, "dfs", -1) == NULL)
+	if (BUS_ADD_CHILD(parent, 10, "dfs", DEVICE_UNIT_ANY) == NULL)
 		device_printf(parent, "add dfs child failed\n");
 }
 
diff --git a/sys/powerpc/cpufreq/mpc85xx_jog.c b/sys/powerpc/cpufreq/mpc85xx_jog.c
--- a/sys/powerpc/cpufreq/mpc85xx_jog.c
+++ b/sys/powerpc/cpufreq/mpc85xx_jog.c
@@ -143,7 +143,7 @@
 	struct ofw_compat_data *compat;
 
 	/* Make sure we're not being doubly invoked. */
-	if (device_find_child(parent, "mpc85xx_jog", -1) != NULL)
+	if (device_find_child(parent, "mpc85xx_jog", DEVICE_UNIT_ANY) != NULL)
 		return;
 
 	compat = mpc85xx_jog_devcompat();
@@ -154,7 +154,7 @@
 	 * We attach a child for every CPU since settings need to
 	 * be performed on every CPU in the SMP case.
 	 */
-	if (BUS_ADD_CHILD(parent, 10, "jog", -1) == NULL)
+	if (BUS_ADD_CHILD(parent, 10, "jog", DEVICE_UNIT_ANY) == NULL)
 		device_printf(parent, "add jog child failed\n");
 }
 
diff --git a/sys/powerpc/cpufreq/pcr.c b/sys/powerpc/cpufreq/pcr.c
--- a/sys/powerpc/cpufreq/pcr.c
+++ b/sys/powerpc/cpufreq/pcr.c
@@ -165,14 +165,14 @@
 	}
 
 	/* Make sure we're not being doubly invoked. */
-	if (device_find_child(parent, "pcr", -1) != NULL)
+	if (device_find_child(parent, "pcr", DEVICE_UNIT_ANY) != NULL)
 		return;
 
 	/*
 	 * We attach a child for every CPU since settings need to
 	 * be performed on every CPU in the SMP case.
 	 */
-	if (BUS_ADD_CHILD(parent, 10, "pcr", -1) == NULL)
+	if (BUS_ADD_CHILD(parent, 10, "pcr", DEVICE_UNIT_ANY) == NULL)
 		device_printf(parent, "add pcr child failed\n");
 }
 
diff --git a/sys/powerpc/cpufreq/pmcr.c b/sys/powerpc/cpufreq/pmcr.c
--- a/sys/powerpc/cpufreq/pmcr.c
+++ b/sys/powerpc/cpufreq/pmcr.c
@@ -115,14 +115,14 @@
 {
 
 	/* Make sure we're not being doubly invoked. */
-	if (device_find_child(parent, "pmcr", -1) != NULL)
+	if (device_find_child(parent, "pmcr", DEVICE_UNIT_ANY) != NULL)
 		return;
 
 	/*
 	 * We attach a child for every CPU since settings need to
 	 * be performed on every CPU in the SMP case.
 	 */
-	if (BUS_ADD_CHILD(parent, 10, "pmcr", -1) == NULL)
+	if (BUS_ADD_CHILD(parent, 10, "pmcr", DEVICE_UNIT_ANY) == NULL)
 		device_printf(parent, "add pmcr child failed\n");
 }
 
diff --git a/sys/powerpc/cpufreq/pmufreq.c b/sys/powerpc/cpufreq/pmufreq.c
--- a/sys/powerpc/cpufreq/pmufreq.c
+++ b/sys/powerpc/cpufreq/pmufreq.c
@@ -89,14 +89,14 @@
 		return;
 
 	/* Make sure we're not being doubly invoked. */
-	if (device_find_child(parent, "pmufreq", -1) != NULL)
+	if (device_find_child(parent, "pmufreq", DEVICE_UNIT_ANY) != NULL)
 		return;
 
 	/*
 	 * We attach a child for every CPU since settings need to
 	 * be performed on every CPU in the SMP case.
 	 */
-	if (BUS_ADD_CHILD(parent, 10, "pmufreq", -1) == NULL)
+	if (BUS_ADD_CHILD(parent, 10, "pmufreq", DEVICE_UNIT_ANY) == NULL)
 		device_printf(parent, "add pmufreq child failed\n");
 }
 
diff --git a/sys/powerpc/powermac/atibl.c b/sys/powerpc/powermac/atibl.c
--- a/sys/powerpc/powermac/atibl.c
+++ b/sys/powerpc/powermac/atibl.c
@@ -105,7 +105,7 @@
 {
 	if (OF_finddevice("mac-io/backlight") == -1)
 		return;
-	if (device_find_child(parent, "backlight", -1) == NULL)
+	if (device_find_child(parent, "backlight", DEVICE_UNIT_ANY) == NULL)
 		device_add_child(parent, "backlight", DEVICE_UNIT_ANY);
 }
 
diff --git a/sys/powerpc/powermac/nvbl.c b/sys/powerpc/powermac/nvbl.c
--- a/sys/powerpc/powermac/nvbl.c
+++ b/sys/powerpc/powermac/nvbl.c
@@ -83,7 +83,7 @@
 {
 	if (OF_finddevice("mac-io/backlight") == -1)
 		return;
-	if (device_find_child(parent, "backlight", -1) == NULL)
+	if (device_find_child(parent, "backlight", DEVICE_UNIT_ANY) == NULL)
 		device_add_child(parent, "backlight", DEVICE_UNIT_ANY);
 }
 
diff --git a/sys/powerpc/powernv/opal_i2c.c b/sys/powerpc/powernv/opal_i2c.c
--- a/sys/powerpc/powernv/opal_i2c.c
+++ b/sys/powerpc/powernv/opal_i2c.c
@@ -137,7 +137,8 @@
 		return (EINVAL);
 	OF_getencprop(ofw_bus_get_node(dev), "ibm,opal-id", &sc->opal_id, len);
 
-	if ((sc->iicbus = device_add_child(dev, "iicbus", -1)) == NULL) {
+	if ((sc->iicbus = device_add_child(dev, "iicbus",
+	    DEVICE_UNIT_ANY)) == NULL) {
 		device_printf(dev, "could not allocate iicbus instance\n");
 		return (EINVAL);
 	}
diff --git a/sys/powerpc/ps3/ps3bus.c b/sys/powerpc/ps3/ps3bus.c
--- a/sys/powerpc/ps3/ps3bus.c
+++ b/sys/powerpc/ps3/ps3bus.c
@@ -157,7 +157,7 @@
 	if (strcmp(installed_platform(), "ps3") != 0)
 		return;
 
-	if (device_find_child(parent, "ps3bus", -1) == NULL)
+	if (device_find_child(parent, "ps3bus", DEVICE_UNIT_ANY) == NULL)
 		BUS_ADD_CHILD(parent, 0, "ps3bus", 0);
 }
 
diff --git a/sys/powerpc/ps3/ps3pic.c b/sys/powerpc/ps3/ps3pic.c
--- a/sys/powerpc/ps3/ps3pic.c
+++ b/sys/powerpc/ps3/ps3pic.c
@@ -99,7 +99,7 @@
 	if (strcmp(installed_platform(), "ps3") != 0)
 		return;
 
-	if (device_find_child(parent, "ps3pic", -1) == NULL)
+	if (device_find_child(parent, "ps3pic", DEVICE_UNIT_ANY) == NULL)
 		BUS_ADD_CHILD(parent, 0, "ps3pic", 0);
 }
 
diff --git a/sys/riscv/riscv/intc.c b/sys/riscv/riscv/intc.c
--- a/sys/riscv/riscv/intc.c
+++ b/sys/riscv/riscv/intc.c
@@ -127,7 +127,7 @@
 	device_t dev;
 	phandle_t node;
 
-	if (device_find_child(parent, "intc", -1) != NULL)
+	if (device_find_child(parent, "intc", DEVICE_UNIT_ANY) != NULL)
 		return;
 
 	node = intc_ofw_find(parent, PCPU_GET(hart));
diff --git a/sys/riscv/riscv/sbi.c b/sys/riscv/riscv/sbi.c
--- a/sys/riscv/riscv/sbi.c
+++ b/sys/riscv/riscv/sbi.c
@@ -351,10 +351,10 @@
 {
 	device_t dev;
 
-	if (device_find_child(parent, "sbi", -1) != NULL)
+	if (device_find_child(parent, "sbi", DEVICE_UNIT_ANY) != NULL)
 		return;
 
-	dev = BUS_ADD_CHILD(parent, 0, "sbi", -1);
+	dev = BUS_ADD_CHILD(parent, 0, "sbi", DEVICE_UNIT_ANY);
 	if (dev == NULL)
 		device_printf(parent, "Can't add sbi child\n");
 }
@@ -389,7 +389,7 @@
 #ifdef SMP
 	di = malloc(sizeof(*di), M_DEVBUF, M_WAITOK | M_ZERO);
 	resource_list_init(&di->rl);
-	child = device_add_child(dev, "sbi_ipi", -1);
+	child = device_add_child(dev, "sbi_ipi", DEVICE_UNIT_ANY);
 	if (child == NULL) {
 		device_printf(dev, "Could not add sbi_ipi child\n");
 		return (ENXIO);
diff --git a/sys/x86/cpufreq/est.c b/sys/x86/cpufreq/est.c
--- a/sys/x86/cpufreq/est.c
+++ b/sys/x86/cpufreq/est.c
@@ -920,11 +920,11 @@
 	 * future.
 	 */
 	intel_hwpstate_identify(NULL, parent);
-	if (device_find_child(parent, "hwpstate_intel", -1) != NULL)
+	if (device_find_child(parent, "hwpstate_intel", DEVICE_UNIT_ANY) != NULL)
 		return;
 
 	/* Make sure we're not being doubly invoked. */
-	if (device_find_child(parent, "est", -1) != NULL)
+	if (device_find_child(parent, "est", DEVICE_UNIT_ANY) != NULL)
 		return;
 
 	/* Check that CPUID is supported and the vendor is Intel.*/
@@ -961,7 +961,8 @@
 	 * If the ACPI perf driver has attached and is not just offering
 	 * info, let it manage things.
 	 */
-	perf_dev = device_find_child(device_get_parent(dev), "acpi_perf", -1);
+	perf_dev = device_find_child(device_get_parent(dev), "acpi_perf",
+	    DEVICE_UNIT_ANY);
 	if (perf_dev && device_is_attached(perf_dev)) {
 		error = CPUFREQ_DRV_TYPE(perf_dev, &type);
 		if (error == 0 && (type & CPUFREQ_FLAG_INFO_ONLY) == 0)
@@ -1064,7 +1065,8 @@
 	int count, error, i, j;
 	uint16_t saved_id16;
 
-	perf_dev = device_find_child(device_get_parent(dev), "acpi_perf", -1);
+	perf_dev = device_find_child(device_get_parent(dev), "acpi_perf",
+	    DEVICE_UNIT_ANY);
 	if (perf_dev == NULL || !device_is_attached(perf_dev))
 		return (ENXIO);
 
diff --git a/sys/x86/cpufreq/hwpstate_amd.c b/sys/x86/cpufreq/hwpstate_amd.c
--- a/sys/x86/cpufreq/hwpstate_amd.c
+++ b/sys/x86/cpufreq/hwpstate_amd.c
@@ -342,7 +342,7 @@
 hwpstate_identify(driver_t *driver, device_t parent)
 {
 
-	if (device_find_child(parent, "hwpstate", -1) != NULL)
+	if (device_find_child(parent, "hwpstate", DEVICE_UNIT_ANY) != NULL)
 		return;
 
 	if ((cpu_vendor_id != CPU_VENDOR_AMD || CPUID_TO_FAMILY(cpu_id) < 0x10) &&
@@ -386,7 +386,8 @@
 	/*
 	 * Check if acpi_perf has INFO only flag.
 	 */
-	perf_dev = device_find_child(device_get_parent(dev), "acpi_perf", -1);
+	perf_dev = device_find_child(device_get_parent(dev), "acpi_perf",
+	    DEVICE_UNIT_ANY);
 	error = TRUE;
 	if (perf_dev && device_is_attached(perf_dev)) {
 		error = CPUFREQ_DRV_TYPE(perf_dev, &type);
diff --git a/sys/x86/cpufreq/hwpstate_intel.c b/sys/x86/cpufreq/hwpstate_intel.c
--- a/sys/x86/cpufreq/hwpstate_intel.c
+++ b/sys/x86/cpufreq/hwpstate_intel.c
@@ -328,7 +328,7 @@
 void
 intel_hwpstate_identify(driver_t *driver, device_t parent)
 {
-	if (device_find_child(parent, "hwpstate_intel", -1) != NULL)
+	if (device_find_child(parent, "hwpstate_intel", DEVICE_UNIT_ANY) != NULL)
 		return;
 
 	if (cpu_vendor_id != CPU_VENDOR_INTEL)
diff --git a/sys/x86/cpufreq/p4tcc.c b/sys/x86/cpufreq/p4tcc.c
--- a/sys/x86/cpufreq/p4tcc.c
+++ b/sys/x86/cpufreq/p4tcc.c
@@ -122,7 +122,7 @@
 		return;
 
 	/* Make sure we're not being doubly invoked. */
-	if (device_find_child(parent, "p4tcc", -1) != NULL)
+	if (device_find_child(parent, "p4tcc", DEVICE_UNIT_ANY) != NULL)
 		return;
 
 	/*
diff --git a/sys/x86/cpufreq/powernow.c b/sys/x86/cpufreq/powernow.c
--- a/sys/x86/cpufreq/powernow.c
+++ b/sys/x86/cpufreq/powernow.c
@@ -870,7 +870,7 @@
 	default:
 		return;
 	}
-	if (device_find_child(parent, "powernow", -1) != NULL)
+	if (device_find_child(parent, "powernow", DEVICE_UNIT_ANY) != NULL)
 		return;
 	if (BUS_ADD_CHILD(parent, 10, "powernow", device_get_unit(parent))
 	    == NULL)
@@ -944,7 +944,8 @@
 	int rv;
 	device_t child;
 
-	child = device_find_child(device_get_parent(dev), "acpi_perf", -1);
+	child = device_find_child(device_get_parent(dev), "acpi_perf",
+	    DEVICE_UNIT_ANY);
 	if (child) {
 		rv = pn_decode_acpi(dev, child);
 		if (rv)
diff --git a/sys/x86/cpufreq/smist.c b/sys/x86/cpufreq/smist.c
--- a/sys/x86/cpufreq/smist.c
+++ b/sys/x86/cpufreq/smist.c
@@ -305,7 +305,7 @@
 	if (bootverbose)
 		printf("smist: found supported isa bridge %s\n", id->desc);
 
-	if (device_find_child(parent, "smist", -1) != NULL)
+	if (device_find_child(parent, "smist", DEVICE_UNIT_ANY) != NULL)
 		return;
 	if (BUS_ADD_CHILD(parent, 30, "smist", device_get_unit(parent))
 	    == NULL)
@@ -330,13 +330,15 @@
 	 * If the ACPI perf or ICH SpeedStep drivers have attached and not
 	 * just offering info, let them manage things.
 	 */
-	perf_dev = device_find_child(device_get_parent(dev), "acpi_perf", -1);
+	perf_dev = device_find_child(device_get_parent(dev), "acpi_perf",
+	    DEVICE_UNIT_ANY);
 	if (perf_dev && device_is_attached(perf_dev)) {
 		rv = CPUFREQ_DRV_TYPE(perf_dev, &type);
 		if (rv == 0 && (type & CPUFREQ_FLAG_INFO_ONLY) == 0)
 			return (ENXIO);
 	}
-	ichss_dev = device_find_child(device_get_parent(dev), "ichss", -1);
+	ichss_dev = device_find_child(device_get_parent(dev), "ichss",
+	    DEVICE_UNIT_ANY);
 	if (ichss_dev && device_is_attached(ichss_dev))
 		return (ENXIO);
 
diff --git a/sys/x86/pci/qpi.c b/sys/x86/pci/qpi.c
--- a/sys/x86/pci/qpi.c
+++ b/sys/x86/pci/qpi.c
@@ -80,7 +80,7 @@
 		return;
 
 	/* Add a qpi bus device. */
-	if (BUS_ADD_CHILD(parent, 20, "qpi", -1) == NULL)
+	if (BUS_ADD_CHILD(parent, 20, "qpi", DEVICE_UNIT_ANY) == NULL)
 		panic("Failed to add qpi bus");
 }