From ac4b4c24acf900fb3d37369f2b0bcd32ab73b455 Mon Sep 17 00:00:00 2001
From: Andrew Thompson <thompsa@FreeBSD.org>
Date: Tue, 23 Dec 2008 19:59:21 +0000
Subject: [PATCH] Remove CALLOUT_RETURNUNLOCKED from the callouts, there is no
 reason for them to drop the lock for us.

---
 sys/dev/usb2/controller/at91dci.c   |  5 +----
 sys/dev/usb2/controller/ehci2.c     | 10 ++--------
 sys/dev/usb2/controller/musb2_otg.c |  5 +----
 sys/dev/usb2/controller/ohci2.c     | 14 +++-----------
 sys/dev/usb2/controller/uhci2.c     |  6 +-----
 sys/dev/usb2/controller/uss820dci.c |  5 +----
 sys/dev/usb2/core/usb2_transfer.c   | 12 ++----------
 sys/dev/usb2/ethernet/if_aue2.c     |  9 ++-------
 sys/dev/usb2/ethernet/if_axe2.c     |  9 ++-------
 sys/dev/usb2/ethernet/if_cue2.c     |  9 ++-------
 sys/dev/usb2/ethernet/if_kue2.c     |  9 ++-------
 sys/dev/usb2/ethernet/if_rue2.c     |  9 ++-------
 sys/dev/usb2/ethernet/if_udav2.c    |  9 ++-------
 sys/dev/usb2/input/ukbd2.c          |  9 +++------
 sys/dev/usb2/input/ums2.c           |  5 +----
 sys/dev/usb2/serial/ulpt2.c         | 10 +++-------
 sys/dev/usb2/wlan/if_rum2.c         |  9 ++-------
 sys/dev/usb2/wlan/if_ural2.c        |  9 ++-------
 sys/dev/usb2/wlan/if_zyd2.c         |  9 ++-------
 19 files changed, 36 insertions(+), 126 deletions(-)

diff --git a/sys/dev/usb2/controller/at91dci.c b/sys/dev/usb2/controller/at91dci.c
index 2827fe62467..a4e43dff698 100644
--- a/sys/dev/usb2/controller/at91dci.c
+++ b/sys/dev/usb2/controller/at91dci.c
@@ -1043,16 +1043,13 @@ static void
 at91dci_timeout(void *arg)
 {
 	struct usb2_xfer *xfer = arg;
-	struct at91dci_softc *sc = xfer->usb2_sc;
 
 	DPRINTF("xfer=%p\n", xfer);
 
-	USB_BUS_LOCK_ASSERT(&sc->sc_bus, MA_OWNED);
+	USB_BUS_LOCK_ASSERT(xfer->udev->bus, MA_OWNED);
 
 	/* transfer is transferred */
 	at91dci_device_done(xfer, USB_ERR_TIMEOUT);
-
-	USB_BUS_UNLOCK(&sc->sc_bus);
 }
 
 static void
diff --git a/sys/dev/usb2/controller/ehci2.c b/sys/dev/usb2/controller/ehci2.c
index c514200a0d5..fdecd7c1b23 100644
--- a/sys/dev/usb2/controller/ehci2.c
+++ b/sys/dev/usb2/controller/ehci2.c
@@ -213,8 +213,7 @@ ehci_init(ehci_softc_t *sc)
 
 	DPRINTF("start\n");
 
-	usb2_callout_init_mtx(&sc->sc_tmo_pcd, &sc->sc_bus.bus_mtx,
-	    CALLOUT_RETURNUNLOCKED);
+	usb2_callout_init_mtx(&sc->sc_tmo_pcd, &sc->sc_bus.bus_mtx, 0);
 
 #if USB_DEBUG
 	if (ehcidebug > 2) {
@@ -1411,8 +1410,6 @@ ehci_pcd_enable(ehci_softc_t *sc)
 
 	usb2_sw_transfer(&sc->sc_root_intr,
 	    &ehci_root_intr_done);
-
-	USB_BUS_UNLOCK(&sc->sc_bus);
 }
 
 static void
@@ -1511,16 +1508,13 @@ static void
 ehci_timeout(void *arg)
 {
 	struct usb2_xfer *xfer = arg;
-	ehci_softc_t *sc = xfer->usb2_sc;
 
 	DPRINTF("xfer=%p\n", xfer);
 
-	USB_BUS_LOCK_ASSERT(&sc->sc_bus, MA_OWNED);
+	USB_BUS_LOCK_ASSERT(xfer->udev->bus, MA_OWNED);
 
 	/* transfer is transferred */
 	ehci_device_done(xfer, USB_ERR_TIMEOUT);
-
-	USB_BUS_UNLOCK(&sc->sc_bus);
 }
 
 static void
diff --git a/sys/dev/usb2/controller/musb2_otg.c b/sys/dev/usb2/controller/musb2_otg.c
index fc839bb60e6..e7119bf30d4 100644
--- a/sys/dev/usb2/controller/musb2_otg.c
+++ b/sys/dev/usb2/controller/musb2_otg.c
@@ -1252,16 +1252,13 @@ static void
 musbotg_timeout(void *arg)
 {
 	struct usb2_xfer *xfer = arg;
-	struct musbotg_softc *sc = xfer->usb2_sc;
 
 	DPRINTFN(1, "xfer=%p\n", xfer);
 
-	USB_BUS_LOCK_ASSERT(&sc->sc_bus, MA_OWNED);
+	USB_BUS_LOCK_ASSERT(xfer->udev->bus, MA_OWNED);
 
 	/* transfer is transferred */
 	musbotg_device_done(xfer, USB_ERR_TIMEOUT);
-
-	USB_BUS_UNLOCK(&sc->sc_bus);
 }
 
 static void
diff --git a/sys/dev/usb2/controller/ohci2.c b/sys/dev/usb2/controller/ohci2.c
index 5ea465c8be9..b3f2f0e86e8 100644
--- a/sys/dev/usb2/controller/ohci2.c
+++ b/sys/dev/usb2/controller/ohci2.c
@@ -390,8 +390,7 @@ ohci_init(ohci_softc_t *sc)
 	/* set up the bus struct */
 	sc->sc_bus.methods = &ohci_bus_methods;
 
-	usb2_callout_init_mtx(&sc->sc_tmo_rhsc, &sc->sc_bus.bus_mtx,
-	    CALLOUT_RETURNUNLOCKED);
+	usb2_callout_init_mtx(&sc->sc_tmo_rhsc, &sc->sc_bus.bus_mtx, 0);
 
 #if USB_DEBUG
 	if (ohcidebug > 15) {
@@ -1095,8 +1094,6 @@ ohci_rhsc_enable(ohci_softc_t *sc)
 
 	usb2_sw_transfer(&sc->sc_root_intr,
 	    &ohci_root_intr_done);
-
-	USB_BUS_UNLOCK(&sc->sc_bus);
 }
 
 static void
@@ -1240,16 +1237,13 @@ static void
 ohci_timeout(void *arg)
 {
 	struct usb2_xfer *xfer = arg;
-	ohci_softc_t *sc = xfer->usb2_sc;
 
 	DPRINTF("xfer=%p\n", xfer);
 
-	USB_BUS_LOCK_ASSERT(&sc->sc_bus, MA_OWNED);
+	USB_BUS_LOCK_ASSERT(xfer->udev->bus, MA_OWNED);
 
 	/* transfer is transferred */
 	ohci_device_done(xfer, USB_ERR_TIMEOUT);
-
-	USB_BUS_UNLOCK(&sc->sc_bus);
 }
 
 static void
@@ -2335,10 +2329,8 @@ ohci_root_ctrl_done(struct usb2_xfer *xfer,
 		case UHF_C_PORT_OVER_CURRENT:
 		case UHF_C_PORT_RESET:
 			/* enable RHSC interrupt if condition is cleared. */
-			if ((OREAD4(sc, port) >> 16) == 0) {
+			if ((OREAD4(sc, port) >> 16) == 0)
 				ohci_rhsc_enable(sc);
-				USB_BUS_LOCK(&sc->sc_bus);
-			}
 			break;
 		default:
 			break;
diff --git a/sys/dev/usb2/controller/uhci2.c b/sys/dev/usb2/controller/uhci2.c
index ceb87e67470..478e54f11b9 100644
--- a/sys/dev/usb2/controller/uhci2.c
+++ b/sys/dev/usb2/controller/uhci2.c
@@ -1494,16 +1494,13 @@ static void
 uhci_timeout(void *arg)
 {
 	struct usb2_xfer *xfer = arg;
-	uhci_softc_t *sc = xfer->usb2_sc;
 
 	DPRINTF("xfer=%p\n", xfer);
 
-	USB_BUS_LOCK_ASSERT(&sc->sc_bus, MA_OWNED);
+	USB_BUS_LOCK_ASSERT(xfer->udev->bus, MA_OWNED);
 
 	/* transfer is transferred */
 	uhci_device_done(xfer, USB_ERR_TIMEOUT);
-
-	USB_BUS_UNLOCK(&sc->sc_bus);
 }
 
 static void
@@ -2912,7 +2909,6 @@ uhci_root_intr_check(void *arg)
 		usb2_sw_transfer(&sc->sc_root_intr,
 		    &uhci_root_intr_done);
 	}
-	USB_BUS_UNLOCK(&sc->sc_bus);
 }
 
 struct usb2_pipe_methods uhci_root_intr_methods =
diff --git a/sys/dev/usb2/controller/uss820dci.c b/sys/dev/usb2/controller/uss820dci.c
index 7148acc1506..d010a538510 100644
--- a/sys/dev/usb2/controller/uss820dci.c
+++ b/sys/dev/usb2/controller/uss820dci.c
@@ -973,16 +973,13 @@ static void
 uss820dci_timeout(void *arg)
 {
 	struct usb2_xfer *xfer = arg;
-	struct uss820dci_softc *sc = xfer->usb2_sc;
 
 	DPRINTF("xfer=%p\n", xfer);
 
-	USB_BUS_LOCK_ASSERT(&sc->sc_bus, MA_OWNED);
+	USB_BUS_LOCK_ASSERT(xfer->udev->bus, MA_OWNED);
 
 	/* transfer is transferred */
 	uss820dci_device_done(xfer, USB_ERR_TIMEOUT);
-
-	USB_BUS_UNLOCK(&sc->sc_bus);
 }
 
 static void
diff --git a/sys/dev/usb2/core/usb2_transfer.c b/sys/dev/usb2/core/usb2_transfer.c
index ede15299a66..1cf6956d962 100644
--- a/sys/dev/usb2/core/usb2_transfer.c
+++ b/sys/dev/usb2/core/usb2_transfer.c
@@ -880,7 +880,7 @@ usb2_transfer_setup(struct usb2_device *udev,
 				info->setup_refcount++;
 
 				usb2_callout_init_mtx(&xfer->timeout_handle,
-				    &udev->bus->bus_mtx, CALLOUT_RETURNUNLOCKED);
+				    &udev->bus->bus_mtx, 0);
 			} else {
 				/*
 				 * Setup a dummy xfer, hence we are
@@ -1950,8 +1950,6 @@ usb2_dma_delay_done_cb(void *arg)
 
 	/* queue callback for execution, again */
 	usb2_transfer_done(xfer, 0);
-
-	USB_BUS_UNLOCK(xfer->udev->bus);
 }
 
 /*------------------------------------------------------------------------*
@@ -2092,7 +2090,6 @@ usb2_transfer_start_cb(void *arg)
 	} else {
 		xfer->flags_int.can_cancel_immed = 0;
 	}
-	USB_BUS_UNLOCK(xfer->udev->bus);
 }
 
 /*------------------------------------------------------------------------*
@@ -2707,14 +2704,9 @@ usb2_callout_poll(struct usb2_xfer *xfer)
 			usb2_callout_stop(co);
 
 			(cb) (arg);
-
-			/* the callback should drop the mutex */
-		} else {
-			mtx_unlock(mtx);
 		}
-	} else {
-		mtx_unlock(mtx);
 	}
+	mtx_unlock(mtx);
 }
 
 
diff --git a/sys/dev/usb2/ethernet/if_aue2.c b/sys/dev/usb2/ethernet/if_aue2.c
index 90fb84968f4..f0bcc04094e 100644
--- a/sys/dev/usb2/ethernet/if_aue2.c
+++ b/sys/dev/usb2/ethernet/if_aue2.c
@@ -770,8 +770,7 @@ aue_attach(device_t dev)
 
 	mtx_init(&sc->sc_mtx, "aue lock", NULL, MTX_DEF | MTX_RECURSE);
 
-	usb2_callout_init_mtx(&sc->sc_watchdog,
-	    &sc->sc_mtx, CALLOUT_RETURNUNLOCKED);
+	usb2_callout_init_mtx(&sc->sc_watchdog, &sc->sc_mtx, 0);
 
 	iface_index = AUE_IFACE_IDX;
 	error = usb2_transfer_setup(uaa->device, &iface_index,
@@ -798,10 +797,8 @@ aue_attach(device_t dev)
 	usb2_config_td_queue_command
 	    (&sc->sc_config_td, NULL, &aue_cfg_first_time_setup, 0, 0);
 
-	/* start watchdog (will exit mutex) */
-
 	aue_watchdog(sc);
-
+	mtx_unlock(&sc->sc_mtx);
 	return (0);			/* success */
 
 detach:
@@ -1475,8 +1472,6 @@ aue_watchdog(void *arg)
 
 	usb2_callout_reset(&sc->sc_watchdog,
 	    hz, &aue_watchdog, sc);
-
-	mtx_unlock(&sc->sc_mtx);
 }
 
 /*
diff --git a/sys/dev/usb2/ethernet/if_axe2.c b/sys/dev/usb2/ethernet/if_axe2.c
index 408546add89..023123599aa 100644
--- a/sys/dev/usb2/ethernet/if_axe2.c
+++ b/sys/dev/usb2/ethernet/if_axe2.c
@@ -597,8 +597,7 @@ axe_attach(device_t dev)
 
 	mtx_init(&sc->sc_mtx, "axe lock", NULL, MTX_DEF | MTX_RECURSE);
 
-	usb2_callout_init_mtx(&sc->sc_watchdog,
-	    &sc->sc_mtx, CALLOUT_RETURNUNLOCKED);
+	usb2_callout_init_mtx(&sc->sc_watchdog, &sc->sc_mtx, 0);
 
 	iface_index = AXE_IFACE_IDX;
 	error = usb2_transfer_setup(uaa->device, &iface_index,
@@ -625,10 +624,8 @@ axe_attach(device_t dev)
 	usb2_config_td_queue_command
 	    (&sc->sc_config_td, NULL, &axe_cfg_first_time_setup, 0, 0);
 
-	/* start watchdog (will exit mutex) */
-
 	axe_watchdog(sc);
-
+	mtx_unlock(&sc->sc_mtx);
 	return (0);			/* success */
 
 detach:
@@ -1423,8 +1420,6 @@ axe_watchdog(void *arg)
 
 	usb2_callout_reset(&sc->sc_watchdog,
 	    hz, &axe_watchdog, sc);
-
-	mtx_unlock(&sc->sc_mtx);
 }
 
 /*
diff --git a/sys/dev/usb2/ethernet/if_cue2.c b/sys/dev/usb2/ethernet/if_cue2.c
index e3ff6875cc1..872af0390fe 100644
--- a/sys/dev/usb2/ethernet/if_cue2.c
+++ b/sys/dev/usb2/ethernet/if_cue2.c
@@ -408,8 +408,7 @@ cue_attach(device_t dev)
 
 	mtx_init(&sc->sc_mtx, "cue lock", NULL, MTX_DEF | MTX_RECURSE);
 
-	usb2_callout_init_mtx(&sc->sc_watchdog,
-	    &sc->sc_mtx, CALLOUT_RETURNUNLOCKED);
+	usb2_callout_init_mtx(&sc->sc_watchdog, &sc->sc_mtx, 0);
 
 	iface_index = CUE_IFACE_IDX;
 	error = usb2_transfer_setup(uaa->device, &iface_index,
@@ -433,10 +432,8 @@ cue_attach(device_t dev)
 	usb2_config_td_queue_command
 	    (&sc->sc_config_td, NULL, &cue_cfg_first_time_setup, 0, 0);
 
-	/* start watchdog (will exit mutex) */
-
 	cue_watchdog(sc);
-
+	mtx_unlock(&sc->sc_mtx);
 	return (0);			/* success */
 
 detach:
@@ -879,8 +876,6 @@ cue_watchdog(void *arg)
 
 	usb2_callout_reset(&sc->sc_watchdog,
 	    hz, &cue_watchdog, sc);
-
-	mtx_unlock(&sc->sc_mtx);
 }
 
 /*
diff --git a/sys/dev/usb2/ethernet/if_kue2.c b/sys/dev/usb2/ethernet/if_kue2.c
index 16232f73aca..060ee1e354e 100644
--- a/sys/dev/usb2/ethernet/if_kue2.c
+++ b/sys/dev/usb2/ethernet/if_kue2.c
@@ -470,8 +470,7 @@ kue_attach(device_t dev)
 
 	mtx_init(&sc->sc_mtx, "kue lock", NULL, MTX_DEF | MTX_RECURSE);
 
-	usb2_callout_init_mtx(&sc->sc_watchdog,
-	    &sc->sc_mtx, CALLOUT_RETURNUNLOCKED);
+	usb2_callout_init_mtx(&sc->sc_watchdog, &sc->sc_mtx, 0);
 
 	iface_index = KUE_IFACE_IDX;
 	error = usb2_transfer_setup(uaa->device, &iface_index,
@@ -495,10 +494,8 @@ kue_attach(device_t dev)
 	usb2_config_td_queue_command
 	    (&sc->sc_config_td, NULL, &kue_cfg_first_time_setup, 0, 0);
 
-	/* start watchdog (will exit mutex) */
-
 	kue_watchdog(sc);
-
+	mtx_unlock(&sc->sc_mtx);
 	return (0);			/* success */
 
 detach:
@@ -935,8 +932,6 @@ kue_watchdog(void *arg)
 
 	usb2_callout_reset(&sc->sc_watchdog,
 	    hz, &kue_watchdog, sc);
-
-	mtx_unlock(&sc->sc_mtx);
 }
 
 static void
diff --git a/sys/dev/usb2/ethernet/if_rue2.c b/sys/dev/usb2/ethernet/if_rue2.c
index 49031b48111..5c788cb70c4 100644
--- a/sys/dev/usb2/ethernet/if_rue2.c
+++ b/sys/dev/usb2/ethernet/if_rue2.c
@@ -651,8 +651,7 @@ rue_attach(device_t dev)
 
 	mtx_init(&sc->sc_mtx, "rue lock", NULL, MTX_DEF | MTX_RECURSE);
 
-	usb2_callout_init_mtx(&sc->sc_watchdog,
-	    &sc->sc_mtx, CALLOUT_RETURNUNLOCKED);
+	usb2_callout_init_mtx(&sc->sc_watchdog, &sc->sc_mtx, 0);
 
 	iface_index = RUE_IFACE_IDX;
 	error = usb2_transfer_setup(uaa->device, &iface_index,
@@ -679,10 +678,8 @@ rue_attach(device_t dev)
 	usb2_config_td_queue_command
 	    (&sc->sc_config_td, NULL, &rue_cfg_first_time_setup, 0, 0);
 
-	/* start watchdog (will exit mutex) */
-
 	rue_watchdog(sc);
-
+	mtx_unlock(&sc->sc_mtx);
 	return (0);			/* success */
 
 detach:
@@ -1299,8 +1296,6 @@ rue_watchdog(void *arg)
 
 	usb2_callout_reset(&sc->sc_watchdog,
 	    hz, &rue_watchdog, sc);
-
-	mtx_unlock(&sc->sc_mtx);
 }
 
 /*
diff --git a/sys/dev/usb2/ethernet/if_udav2.c b/sys/dev/usb2/ethernet/if_udav2.c
index 9514840f91f..2cc3596cd09 100644
--- a/sys/dev/usb2/ethernet/if_udav2.c
+++ b/sys/dev/usb2/ethernet/if_udav2.c
@@ -282,8 +282,7 @@ udav_attach(device_t dev)
 
 	mtx_init(&sc->sc_mtx, "udav lock", NULL, MTX_DEF | MTX_RECURSE);
 
-	usb2_callout_init_mtx(&sc->sc_watchdog,
-	    &sc->sc_mtx, CALLOUT_RETURNUNLOCKED);
+	usb2_callout_init_mtx(&sc->sc_watchdog, &sc->sc_mtx, 0);
 
 	iface_index = UDAV_IFACE_INDEX;
 	error = usb2_transfer_setup(uaa->device, &iface_index,
@@ -309,10 +308,8 @@ udav_attach(device_t dev)
 	usb2_config_td_queue_command
 	    (&sc->sc_config_td, NULL, &udav_cfg_first_time_setup, 0, 0);
 
-	/* start watchdog (will exit mutex) */
-
 	udav_watchdog(sc);
-
+	mtx_unlock(&sc->sc_mtx);
 	return (0);			/* success */
 
 detach:
@@ -1080,8 +1077,6 @@ udav_watchdog(void *arg)
 
 	usb2_callout_reset(&sc->sc_watchdog,
 	    hz, &udav_watchdog, sc);
-
-	mtx_unlock(&sc->sc_mtx);
 }
 
 /*
diff --git a/sys/dev/usb2/input/ukbd2.c b/sys/dev/usb2/input/ukbd2.c
index 52d9dbe097a..8cff11fb8a5 100644
--- a/sys/dev/usb2/input/ukbd2.c
+++ b/sys/dev/usb2/input/ukbd2.c
@@ -445,8 +445,6 @@ ukbd_timeout(void *arg)
 	ukbd_interrupt(sc);
 
 	usb2_callout_reset(&sc->sc_callout, hz / 40, &ukbd_timeout, sc);
-
-	mtx_unlock(&Giant);
 }
 
 static void
@@ -639,8 +637,7 @@ ukbd_attach(device_t dev)
 	sc->sc_mode = K_XLATE;
 	sc->sc_iface = uaa->iface;
 
-	usb2_callout_init_mtx(&sc->sc_callout, &Giant,
-	    CALLOUT_RETURNUNLOCKED);
+	usb2_callout_init_mtx(&sc->sc_callout, &Giant, 0);
 
 	err = usb2_transfer_setup(uaa->device,
 	    &uaa->info.bIfaceIndex, sc->sc_xfer, ukbd_config,
@@ -705,8 +702,8 @@ ukbd_attach(device_t dev)
 
 	/* start the timer */
 
-	ukbd_timeout(sc);		/* will unlock mutex */
-
+	ukbd_timeout(sc);
+	mtx_unlock(&Giant);
 	return (0);			/* success */
 
 detach:
diff --git a/sys/dev/usb2/input/ums2.c b/sys/dev/usb2/input/ums2.c
index 7dbcd1c242b..0c3fa061c13 100644
--- a/sys/dev/usb2/input/ums2.c
+++ b/sys/dev/usb2/input/ums2.c
@@ -153,8 +153,6 @@ ums_put_queue_timeout(void *__sc)
 	mtx_assert(&sc->sc_mtx, MA_OWNED);
 
 	ums_put_queue(sc, 0, 0, 0, 0, 0);
-
-	mtx_unlock(&sc->sc_mtx);
 }
 
 static void
@@ -415,8 +413,7 @@ ums_attach(device_t dev)
 
 	mtx_init(&sc->sc_mtx, "ums lock", NULL, MTX_DEF | MTX_RECURSE);
 
-	usb2_callout_init_mtx(&sc->sc_callout,
-	    &sc->sc_mtx, CALLOUT_RETURNUNLOCKED);
+	usb2_callout_init_mtx(&sc->sc_callout, &sc->sc_mtx, 0);
 
 	/*
          * Force the report (non-boot) protocol.
diff --git a/sys/dev/usb2/serial/ulpt2.c b/sys/dev/usb2/serial/ulpt2.c
index d95b0fc1407..4b9f44b7d3e 100644
--- a/sys/dev/usb2/serial/ulpt2.c
+++ b/sys/dev/usb2/serial/ulpt2.c
@@ -560,8 +560,7 @@ ulpt_attach(device_t dev)
 
 	mtx_init(&sc->sc_mtx, "ulpt lock", NULL, MTX_DEF | MTX_RECURSE);
 
-	usb2_callout_init_mtx(&sc->sc_watchdog,
-	    &sc->sc_mtx, CALLOUT_RETURNUNLOCKED);
+	usb2_callout_init_mtx(&sc->sc_watchdog, &sc->sc_mtx, 0);
 
 	/* search through all the descriptors looking for bidir mode */
 
@@ -671,9 +670,8 @@ found:
 	/* start reading of status */
 
 	mtx_lock(&sc->sc_mtx);
-
-	ulpt_watchdog(sc);		/* will unlock mutex */
-
+	ulpt_watchdog(sc);
+	mtx_unlock(&sc->sc_mtx);
 	return (0);
 
 detach:
@@ -762,8 +760,6 @@ ulpt_watchdog(void *arg)
 
 	usb2_callout_reset(&sc->sc_watchdog,
 	    hz, &ulpt_watchdog, sc);
-
-	mtx_unlock(&sc->sc_mtx);
 }
 
 static devclass_t ulpt_devclass;
diff --git a/sys/dev/usb2/wlan/if_rum2.c b/sys/dev/usb2/wlan/if_rum2.c
index a001d8d82de..e99881ba736 100644
--- a/sys/dev/usb2/wlan/if_rum2.c
+++ b/sys/dev/usb2/wlan/if_rum2.c
@@ -475,8 +475,7 @@ rum_attach(device_t dev)
 	sc->sc_udev = uaa->device;
 	sc->sc_unit = device_get_unit(dev);
 
-	usb2_callout_init_mtx(&sc->sc_watchdog,
-	    &sc->sc_mtx, CALLOUT_RETURNUNLOCKED);
+	usb2_callout_init_mtx(&sc->sc_watchdog, &sc->sc_mtx, 0);
 
 	iface_index = RT2573_IFACE_INDEX;
 	error = usb2_transfer_setup(uaa->device, &iface_index,
@@ -501,10 +500,8 @@ rum_attach(device_t dev)
 	usb2_config_td_queue_command
 	    (&sc->sc_config_td, NULL, &rum_cfg_first_time_setup, 0, 0);
 
-	/* start watchdog (will exit mutex) */
-
 	rum_watchdog(sc);
-
+	mtx_unlock(&sc->sc_mtx);
 	return (0);			/* success */
 
 detach:
@@ -1417,8 +1414,6 @@ rum_watchdog(void *arg)
 	}
 	usb2_callout_reset(&sc->sc_watchdog,
 	    hz, &rum_watchdog, sc);
-
-	mtx_unlock(&sc->sc_mtx);
 }
 
 static void
diff --git a/sys/dev/usb2/wlan/if_ural2.c b/sys/dev/usb2/wlan/if_ural2.c
index 0af78c7e356..22134392cdd 100644
--- a/sys/dev/usb2/wlan/if_ural2.c
+++ b/sys/dev/usb2/wlan/if_ural2.c
@@ -468,8 +468,7 @@ ural_attach(device_t dev)
 	sc->sc_udev = uaa->device;
 	sc->sc_unit = device_get_unit(dev);
 
-	usb2_callout_init_mtx(&sc->sc_watchdog,
-	    &sc->sc_mtx, CALLOUT_RETURNUNLOCKED);
+	usb2_callout_init_mtx(&sc->sc_watchdog, &sc->sc_mtx, 0);
 
 	iface_index = RAL_IFACE_INDEX;
 	error = usb2_transfer_setup(uaa->device,
@@ -496,10 +495,8 @@ ural_attach(device_t dev)
 	usb2_config_td_queue_command
 	    (&sc->sc_config_td, NULL, &ural_cfg_first_time_setup, 0, 0);
 
-	/* start watchdog (will exit mutex) */
-
 	ural_watchdog(sc);
-
+	mtx_unlock(&sc->sc_mtx);
 	return (0);			/* success */
 
 detach:
@@ -1405,8 +1402,6 @@ ural_watchdog(void *arg)
 	}
 	usb2_callout_reset(&sc->sc_watchdog,
 	    hz, &ural_watchdog, sc);
-
-	mtx_unlock(&sc->sc_mtx);
 }
 
 /*========================================================================*
diff --git a/sys/dev/usb2/wlan/if_zyd2.c b/sys/dev/usb2/wlan/if_zyd2.c
index d71516012a0..2e29d3769f5 100644
--- a/sys/dev/usb2/wlan/if_zyd2.c
+++ b/sys/dev/usb2/wlan/if_zyd2.c
@@ -1080,8 +1080,7 @@ zyd_attach(device_t dev)
 
 	usb2_cv_init(&sc->sc_intr_cv, "IWAIT");
 
-	usb2_callout_init_mtx(&sc->sc_watchdog,
-	    &sc->sc_mtx, CALLOUT_RETURNUNLOCKED);
+	usb2_callout_init_mtx(&sc->sc_watchdog, &sc->sc_mtx, 0);
 
 	/*
 	 * Endpoint 1 = Bulk out (512b @ high speed / 64b @ full speed)
@@ -1111,10 +1110,8 @@ zyd_attach(device_t dev)
 	usb2_config_td_queue_command
 	    (&sc->sc_config_td, NULL, &zyd_cfg_first_time_setup, 0, 0);
 
-	/* start watchdog (will exit mutex) */
-
 	zyd_watchdog(sc);
-
+	mtx_unlock(&sc->sc_mtx);
 	return (0);
 
 detach:
@@ -2761,8 +2758,6 @@ zyd_watchdog(void *arg)
 	}
 	usb2_callout_reset(&sc->sc_watchdog,
 	    hz, &zyd_watchdog, sc);
-
-	mtx_unlock(&sc->sc_mtx);
 }
 
 static void