- Convert a lot of homebrew debugging output to use the ACPI CA debugging

   infrastructure.  It's not perfect, but it's a lot better than what
   we've been using so far.  The following rules apply to this:
    o BSD component names should be capitalised
    o Layer names should be taken from the non-CA set for now.  We
      may elect to add some new BSD-specific layers later.

 - Make it possible to turn off selective debugging flags or layers
   by listing them in debug.acpi.layer or debug.acpi.level prefixed
   with !.

 - Fully implement support for avoiding nodes in the ACPI namespace.
   Nodes may be listed in the debug.acpi.avoid environment variable;
   these nodes and all their children will be ignored (although still
   scanned over) by ACPI functions which scan the namespace.  Multiple
   nodes can be specified, separated by whitespace.

 - Implement support for selectively disabling ACPI subsystem components
   via the debug.acpi.disable environment variable.  The following
   components can be disabled:
    o bus	creation/scanning of the ACPI 'bus'
    o children	attachment of children to the ACPI 'bus'
    o button	the acpi_button control-method button driver
    o ec	the acpi_ec embedded-controller driver
    o isa	acpi replacement of PnP BIOS for ISA device discovery
    o lid	the control-method lid switch driver
    o pci	pci root-bus discovery
    o processor CPU power/speed management
    o thermal	system temperature detection and control
    o timer	ACPI timecounter
   Multiple components may be disabled by specifying their name(s)
   separated by whitespace.

 - Add support for ioctl registration.  ACPI subsystem components may
   register ioctl handlers with the /dev/acpi generic ioctl handler,
   allowing us to avoid the need for a multitude of /dev/acpi* control
   devices, etc.

13 files changed, 512 insertions, 196 deletions

diff --git a/sys/dev/acpica/acpi.c b/sys/dev/acpica/acpi.c
index 5095c54..3bb3a9b 100644
--- a/sys/dev/acpica/acpi.c
+++ b/sys/dev/acpica/acpi.c
@@ -52,6 +52,12 @@
 MALLOC_DEFINE(M_ACPIDEV, "acpidev", "ACPI devices");
 
 /*
+ * Hooks for the ACPI CA debugging infrastructure
+ */
+#define _COMPONENT	BUS_MANAGER
+MODULE_NAME("ACPI")
+
+/*
  * Character device 
  */
 
@@ -159,6 +165,8 @@ acpi_identify(driver_t *driver, device_t parent)
     char			*debugpoint = getenv("debug.acpi.debugger");
 #endif
 
+    FUNCTION_TRACE(__FUNCTION__);
+
     if(!cold){
 	    printf("Don't load this driver from userland!!\n");
 	    return ;
@@ -168,7 +176,7 @@ acpi_identify(driver_t *driver, device_t parent)
      * Make sure we're not being doubly invoked.
      */
     if (device_find_child(parent, "acpi", 0) != NULL)
-	return;
+	return_VOID;
     
 #ifdef ACPI_DEBUG
     acpi_set_debugging();
@@ -183,7 +191,7 @@ acpi_identify(driver_t *driver, device_t parent)
 #endif
     if ((error = AcpiInitializeSubsystem()) != AE_OK) {
 	printf("ACPI: initialisation failed: %s\n", acpi_strerror(error));
-	return;
+	return_VOID;
     }
 #ifdef ENABLE_DEBUGGER
     if (debugpoint && !strcmp(debugpoint, "tables"))
@@ -192,7 +200,7 @@ acpi_identify(driver_t *driver, device_t parent)
     if (((error = AcpiFindRootPointer(&rsdp)) != AE_OK) ||
 	((error = AcpiLoadTables(rsdp)) != AE_OK)) {
 	printf("ACPI: table load failed: %s\n", acpi_strerror(error));
-	return;
+	return_VOID;
     }
     
     /*
@@ -200,7 +208,7 @@ acpi_identify(driver_t *driver, device_t parent)
      */
     if ((child = BUS_ADD_CHILD(parent, 0, "acpi", 0)) == NULL) {
 	    device_printf(parent, "ACPI: could not attach\n");
-	    return;
+	    return_VOID;
     }
 }
 
@@ -214,14 +222,16 @@ acpi_probe(device_t dev)
     char		buf[20];
     int			error;
 
+    FUNCTION_TRACE(__FUNCTION__);
+
     if ((error = AcpiGetTableHeader(ACPI_TABLE_XSDT, 1, &th)) != AE_OK) {
 	device_printf(dev, "couldn't get XSDT header: %s\n", acpi_strerror(error));
-	return(ENXIO);
+	return_VALUE(ENXIO);
     }
     sprintf(buf, "%.6s %.8s", th.OemId, th.OemTableId);
     device_set_desc_copy(dev, buf);
 
-    return(0);
+    return_VALUE(0);
 }
 
 static int
@@ -233,6 +243,7 @@ acpi_attach(device_t dev)
     char		*debugpoint = getenv("debug.acpi.debugger");
 #endif
 
+    FUNCTION_TRACE(__FUNCTION__);
 
     sc = device_get_softc(dev);
     bzero(sc, sizeof(*sc));
@@ -251,21 +262,21 @@ acpi_attach(device_t dev)
 						ACPI_DEFAULT_HANDLER,
 						NULL, NULL)) != AE_OK) {
 	device_printf(dev, "could not initialise SystemMemory handler: %s\n", acpi_strerror(error));
-	return(ENXIO);
+	return_VALUE(ENXIO);
     }
     if ((error = AcpiInstallAddressSpaceHandler(ACPI_ROOT_OBJECT,
 						ADDRESS_SPACE_SYSTEM_IO,
 						ACPI_DEFAULT_HANDLER,
 						NULL, NULL)) != AE_OK) {
 	device_printf(dev, "could not initialise SystemIO handler: %s\n", acpi_strerror(error));
-	return(ENXIO);
+	return_VALUE(ENXIO);
     }
     if ((error = AcpiInstallAddressSpaceHandler(ACPI_ROOT_OBJECT,
 						ADDRESS_SPACE_PCI_CONFIG,
 						ACPI_DEFAULT_HANDLER,
 						NULL, NULL)) != AE_OK) {
 	device_printf(dev, "could not initialise PciConfig handler: %s\n", acpi_strerror(error));
-	return(ENXIO);
+	return_VALUE(ENXIO);
     }
 
     /*
@@ -283,7 +294,7 @@ acpi_attach(device_t dev)
 #endif
     if ((error = AcpiEnableSubsystem(ACPI_NO_DEVICE_INIT | ACPI_NO_OBJECT_INIT)) != AE_OK) {
 	device_printf(dev, "could not enable ACPI: %s\n", acpi_strerror(error));
-	return(ENXIO);
+	return_VALUE(ENXIO);
     }
 
     /*
@@ -315,7 +326,8 @@ acpi_attach(device_t dev)
     if (debugpoint && !strcmp(debugpoint, "probe"))
 	acpi_EnterDebugger();
 #endif
-    acpi_probe_children(dev);
+    if (!acpi_disabled("bus"))
+	acpi_probe_children(dev);
 
     /*
      * Register our shutdown handlers
@@ -346,7 +358,7 @@ acpi_attach(device_t dev)
     if (debugpoint && !strcmp(debugpoint, "running"))
 	acpi_EnterDebugger();
 #endif
-    return(0);
+    return_VALUE(0);
 }
 
 /*
@@ -547,9 +559,12 @@ acpi_probe_children(device_t bus)
     static char		*scopes[] = {"\\_TZ_", "\\_SI", "\\_SB_", NULL};
     int			i;
 
+    FUNCTION_TRACE(__FUNCTION__);
+
     /*
      * Create any static children by calling device identify methods.
      */
+    DEBUG_PRINT(TRACE_OBJECTS, ("device identify routines\n"));
     bus_generic_probe(bus);
 
     /*
@@ -561,6 +576,7 @@ acpi_probe_children(device_t bus)
      * present. (This assumes that we don't want to create/remove devices as they
      * appear, which might be smarter.)
      */
+    DEBUG_PRINT(TRACE_OBJECTS, ("namespace scan\n"));
     for (i = 0; scopes[i] != NULL; i++)
 	if ((AcpiGetHandle(ACPI_ROOT_OBJECT, scopes[i], &parent)) == AE_OK)
 	    AcpiWalkNamespace(ACPI_TYPE_ANY, parent, 100, acpi_probe_child, bus, NULL);
@@ -568,13 +584,17 @@ acpi_probe_children(device_t bus)
     /*
      * Scan all of the child devices we have created and let them probe/attach.
      */
+    DEBUG_PRINT(TRACE_OBJECTS, ("first bus_generic_attach\n"));
     bus_generic_attach(bus);
 
     /*
      * Some of these children may have attached others as part of their attach
      * process (eg. the root PCI bus driver), so rescan.
      */
+    DEBUG_PRINT(TRACE_OBJECTS, ("second bus_generic_attach\n"));
     bus_generic_attach(bus);
+
+    return_VOID;
 }
 
 /*
@@ -587,28 +607,41 @@ acpi_probe_child(ACPI_HANDLE handle, UINT32 level, void *context, void **status)
     ACPI_OBJECT_TYPE	type;
     device_t		child, bus = (device_t)context;
 
+    FUNCTION_TRACE(__FUNCTION__);
+
+    /*
+     * Skip this device if we think we'll have trouble with it.
+     */
+    if (acpi_avoid(handle))
+	return_ACPI_STATUS(AE_OK);
+
     if (AcpiGetType(handle, &type) == AE_OK) {
 	switch(type) {
 	case ACPI_TYPE_DEVICE:
 	case ACPI_TYPE_PROCESSOR:
 	case ACPI_TYPE_THERMAL:
 	case ACPI_TYPE_POWER:
+	    if (acpi_disabled("children"))
+		break;
 	    /* 
 	     * Create a placeholder device for this node.  Sort the placeholder
 	     * so that the probe/attach passes will run breadth-first.
 	     */
+	    DEBUG_PRINT(TRACE_OBJECTS, ("scanning '%s'\n", acpi_name(handle)))
 	    child = BUS_ADD_CHILD(bus, level * 10, NULL, -1);
 	    acpi_set_handle(child, handle);
+	    DEBUG_EXEC(device_probe_and_attach(child));
+	    break;
 	}
     }
-    return(AE_OK);
+    return_ACPI_STATUS(AE_OK);
 }
 
 static void
 acpi_shutdown_pre_sync(void *arg, int howto)
 {
     /*
-     * disable all of ACPI events before soft off, otherwise the system
+     * Disable all ACPI events before soft off, otherwise the system
      * will be turned on again on some laptops.
      *
      * XXX this should probably be restricted to masking some events just
@@ -643,7 +676,7 @@ acpi_MatchHid(device_t dev, char *hid)
     ACPI_HANDLE		h;
     ACPI_DEVICE_INFO	devinfo;
     ACPI_STATUS		error;
-    
+
     if (hid == NULL)
 	return(FALSE);
     if ((h = acpi_get_handle(dev)) == NULL)
@@ -699,6 +732,8 @@ acpi_SetSleepState(struct acpi_softc *sc, int state)
 {
     ACPI_STATUS	status = AE_OK;
 
+    FUNCTION_TRACE_U32(__FUNCTION__, state);
+
     switch (state) {
     case ACPI_STATE_S0:	/* XXX only for testing */
 	status = AcpiSetSystemSleepState((UINT8)state);
@@ -720,7 +755,7 @@ acpi_SetSleepState(struct acpi_softc *sc, int state)
 	     *     current bus interface does not provide for this.
 	     */
 	    DEVICE_RESUME(root_bus);
-	    return(AE_ERROR);
+	    return_ACPI_STATUS(AE_ERROR);
 	}
 	sc->acpi_sstate = state;
 	status = AcpiSetSystemSleepState((UINT8)state);
@@ -743,7 +778,7 @@ acpi_SetSleepState(struct acpi_softc *sc, int state)
 	status = AE_BAD_PARAMETER;
 	break;
     }
-    return(status);
+    return_ACPI_STATUS(status);
 }
 
 /*
@@ -755,6 +790,8 @@ acpi_Enable(struct acpi_softc *sc)
     ACPI_STATUS	status;
     u_int32_t	flags;
 
+    FUNCTION_TRACE(__FUNCTION__);
+
     flags = ACPI_NO_ADDRESS_SPACE_INIT | ACPI_NO_HARDWARE_INIT |
             ACPI_NO_DEVICE_INIT | ACPI_NO_OBJECT_INIT;
     if (!sc->acpi_enabled) {
@@ -764,7 +801,7 @@ acpi_Enable(struct acpi_softc *sc)
     }
     if (status == AE_OK)
 	sc->acpi_enabled = 1;
-    return(status);
+    return_ACPI_STATUS(status);
 }
 
 ACPI_STATUS
@@ -772,6 +809,8 @@ acpi_Disable(struct acpi_softc *sc)
 {
     ACPI_STATUS	status;
 
+    FUNCTION_TRACE(__FUNCTION__);
+
     if (sc->acpi_enabled) {
 	status = AcpiDisable();
     } else {
@@ -779,7 +818,7 @@ acpi_Disable(struct acpi_softc *sc)
     }
     if (status == AE_OK)
 	sc->acpi_enabled = 0;
-    return(status);
+    return_ACPI_STATUS(status);
 }
 
 /*
@@ -836,18 +875,21 @@ acpi_EvaluateNumber(ACPI_HANDLE handle, char *path, int *number)
 static void
 acpi_system_eventhandler_sleep(void *arg, int state)
 {
-    if (state < ACPI_STATE_S0 || state > ACPI_STATE_S5) {
-	return;
-    }
+    FUNCTION_TRACE_U32(__FUNCTION__, state);
 
-    acpi_SetSleepState((struct acpi_softc *)arg, state);
+    if (state >= ACPI_STATE_S0 && state <= ACPI_STATE_S5)
+	acpi_SetSleepState((struct acpi_softc *)arg, state);
+    return_VOID;
 }
 
-
 static void
 acpi_system_eventhandler_wakeup(void *arg, int state)
 {
+    FUNCTION_TRACE_U32(__FUNCTION__, state);
+
     /* Well, what to do? :-) */
+
+    return_VOID;
 }
 
 /* 
@@ -858,8 +900,11 @@ acpi_eventhandler_power_button_for_sleep(void *context)
 {
     struct acpi_softc	*sc = (struct acpi_softc *)context;
 
+    FUNCTION_TRACE(__FUNCTION__);
+
     EVENTHANDLER_INVOKE(acpi_sleep_event, sc->acpi_power_button_sx);
-    return(INTERRUPT_HANDLED);
+
+    return_VALUE(INTERRUPT_HANDLED);
 }
 
 UINT32
@@ -867,8 +912,11 @@ acpi_eventhandler_power_button_for_wakeup(void *context)
 {
     struct acpi_softc	*sc = (struct acpi_softc *)context;
 
+    FUNCTION_TRACE(__FUNCTION__);
+
     EVENTHANDLER_INVOKE(acpi_wakeup_event, sc->acpi_power_button_sx);
-    return(INTERRUPT_HANDLED);
+
+    return_VALUE(INTERRUPT_HANDLED);
 }
 
 UINT32
@@ -876,8 +924,11 @@ acpi_eventhandler_sleep_button_for_sleep(void *context)
 {
     struct acpi_softc	*sc = (struct acpi_softc *)context;
 
+    FUNCTION_TRACE(__FUNCTION__);
+
     EVENTHANDLER_INVOKE(acpi_sleep_event, sc->acpi_sleep_button_sx);
-    return(INTERRUPT_HANDLED);
+
+    return_VALUE(INTERRUPT_HANDLED);
 }
 
 UINT32
@@ -885,8 +936,11 @@ acpi_eventhandler_sleep_button_for_wakeup(void *context)
 {
     struct acpi_softc	*sc = (struct acpi_softc *)context;
 
+    FUNCTION_TRACE(__FUNCTION__);
+
     EVENTHANDLER_INVOKE(acpi_wakeup_event, sc->acpi_sleep_button_sx);
-    return(INTERRUPT_HANDLED);
+
+    return_VALUE(INTERRUPT_HANDLED);
 }
 
 /*
@@ -949,7 +1003,39 @@ acpi_avoid(ACPI_HANDLE handle)
 	while ((cp[len] != 0) && !isspace(cp[len]))
 	    len++;
 	if (!strncmp(cp, np, len)) {
-	    printf("avoiding '%s'\n", np);
+	    DEBUG_PRINT(TRACE_OBJECTS, ("avoiding '%s'\n", np));
+	    return(1);
+	}
+	cp += len;
+    }
+    return(0);
+}
+
+/*
+ * Debugging/bug-avoidance.  Disable ACPI subsystem components.
+ */
+int
+acpi_disabled(char *subsys)
+{
+    char	*cp;
+    int		len;
+
+    if ((cp = getenv("debug.acpi.disable")) == NULL)
+	return(0);
+    if (!strcmp(cp, "all"))
+	return(1);
+
+    /* scan the disable list checking for a match */
+    for (;;) {
+	while ((*cp != 0) && isspace(*cp))
+	    cp++;
+	if (*cp == 0)
+	    break;
+	len = 0;
+	while ((cp[len] != 0) && !isspace(cp[len]))
+	    len++;
+	if (!strncmp(cp, subsys, len)) {
+	    DEBUG_PRINT(TRACE_OBJECTS, ("disabled '%s'\n", subsys));
 	    return(1);
 	}
 	cp += len;
@@ -960,42 +1046,107 @@ acpi_avoid(ACPI_HANDLE handle)
 /*
  * Control interface.
  *
- * XXX this is provided as a temporary measure for
- *     backwards compatibility for now.  A better
- *     interface will probably use sysctl or similar.
+ * We multiplex ioctls for all participating ACPI devices here.  Individual 
+ * drivers wanting to be accessible via /dev/acpi should use the register/deregister
+ * interface to make their handlers visible.
  */
+struct acpi_ioctl_hook
+{
+    TAILQ_ENTRY(acpi_ioctl_hook)	link;
+    u_long				cmd;
+    int					(* fn)(u_long cmd, caddr_t addr, void *arg);
+    void				*arg;
+};
+
+static TAILQ_HEAD(,acpi_ioctl_hook)	acpi_ioctl_hooks;
+static int				acpi_ioctl_hooks_initted;
+
+/*
+ * Register an ioctl handler.
+ */
+int
+acpi_register_ioctl(u_long cmd, int (* fn)(u_long cmd, caddr_t addr, void *arg), void *arg)
+{
+    struct acpi_ioctl_hook	*hp;
+
+    if ((hp = malloc(sizeof(*hp), M_ACPIDEV, M_NOWAIT)) == NULL)
+	return(ENOMEM);
+    hp->cmd = cmd;
+    hp->fn = fn;
+    hp->arg = arg;
+    if (acpi_ioctl_hooks_initted == 0) {
+	TAILQ_INIT(&acpi_ioctl_hooks);
+	acpi_ioctl_hooks_initted = 1;
+    }
+    TAILQ_INSERT_TAIL(&acpi_ioctl_hooks, hp, link);
+    return(0);
+}
+
+/*
+ * Deregister an ioctl handler.
+ */
+void	
+acpi_deregister_ioctl(u_long cmd, int (* fn)(u_long cmd, caddr_t addr, void *arg))
+{
+    struct acpi_ioctl_hook	*hp;
+
+    TAILQ_FOREACH(hp, &acpi_ioctl_hooks, link)
+	if ((hp->cmd == cmd) && (hp->fn == fn))
+	    break;
+
+    if (hp != NULL) {
+	TAILQ_REMOVE(&acpi_ioctl_hooks, hp, link);
+	free(hp, M_ACPIDEV);
+    }
+}
+
 static int
-acpiopen(dev_t dev, int flag, int fmt, struct proc * p)
+acpiopen(dev_t dev, int flag, int fmt, struct proc *p)
 {
     return(0);
 }
 
 static int
-acpiclose(dev_t dev, int flag, int fmt, struct proc * p)
+acpiclose(dev_t dev, int flag, int fmt, struct proc *p)
 {
     return(0);
 }
 
 static int
-acpiioctl(dev_t dev, u_long cmd, caddr_t addr, int flag, struct proc * p)
+acpiioctl(dev_t dev, u_long cmd, caddr_t addr, int flag, struct proc *p)
 {
-    int		error, state;
-    struct acpi_softc	*sc;
+    struct acpi_softc		*sc;
+    struct acpi_ioctl_hook	*hp;
+    int				error, xerror, state;
 
     error = state = 0;
     sc = dev->si_drv1;
 
+    /*
+     * Scan the list of registered ioctls, looking for handlers.
+     */
+    if (acpi_ioctl_hooks_initted) {
+	TAILQ_FOREACH(hp, &acpi_ioctl_hooks, link) {
+	    if (hp->cmd == cmd) {
+		xerror = hp->fn(cmd, addr, hp->arg);
+		if (xerror != 0)
+		    error = xerror;
+	    }
+	}
+    }
+
+    /*
+     * Core system ioctls.
+     */
     switch (cmd) {
     case ACPIIO_ENABLE:
-	if (ACPI_FAILURE(acpi_Enable(sc))) {
+	if (ACPI_FAILURE(acpi_Enable(sc)))
 	    error = ENXIO;
-	}
 	break;
 
     case ACPIIO_DISABLE:
-	if (ACPI_FAILURE(acpi_Disable(sc))) {
+	if (ACPI_FAILURE(acpi_Disable(sc)))
 	    error = ENXIO;
-	}
 	break;
 
     case ACPIIO_SETSLPSTATE:
@@ -1009,18 +1160,25 @@ acpiioctl(dev_t dev, u_long cmd, caddr_t addr, int flag, struct proc * p)
 	} else {
 	    error = EINVAL;
 	}
-
 	break;
 
     default:
-	error = EINVAL;
+	if (error == 0)
+	    error = EINVAL;
 	break;
     }
-
     return(error);
 }
 
 #ifdef ACPI_DEBUG
+/*
+ * Support for parsing debug options from the kernel environment.
+ *
+ * Bits may be set in the AcpiDbgLayer and AcpiDbgLevel debug registers
+ * by specifying the names of the bits in the debug.acpi.layer and
+ * debug.acpi.level environment variables.  Bits may be unset by 
+ * prefixing the bit name with !.
+ */
 struct debugtag
 {
     char	*name;
@@ -1093,6 +1251,7 @@ acpi_parse_debug(char *cp, struct debugtag *tag, UINT32 *flag)
 {
     char	*ep;
     int		i, l;
+    int		set;
 
     while (*cp) {
 	if (isspace(*cp)) {
@@ -1102,10 +1261,22 @@ acpi_parse_debug(char *cp, struct debugtag *tag, UINT32 *flag)
 	ep = cp;
 	while (*ep && !isspace(*ep))
 	    ep++;
+	if (*cp == '!') {
+	    set = 0;
+	    cp++;
+	    if (cp == ep)
+		continue;
+	} else {
+	    set = 1;
+	}
 	l = ep - cp;
 	for (i = 0; tag[i].name != NULL; i++) {
 	    if (!strncmp(cp, tag[i].name, l)) {
-		*flag |= tag[i].value;
+		if (set) {
+		    *flag |= tag[i].value;
+		} else {
+		    *flag &= ~tag[i].value;
+		}
 		printf("ACPI_DEBUG: set '%s'\n", tag[i].name);
 	    }
 	}
@@ -1117,10 +1288,14 @@ static void
 acpi_set_debugging(void)
 {
     char	*cp;
-    
+
+    AcpiDbgLayer = 0;
+    AcpiDbgLevel = 0;
     if ((cp = getenv("debug.acpi.layer")) != NULL)
 	acpi_parse_debug(cp, &dbg_layer[0], &AcpiDbgLayer);
     if ((cp = getenv("debug.acpi.level")) != NULL)
 	acpi_parse_debug(cp, &dbg_level[0], &AcpiDbgLevel);
+
+    printf("ACPI debug layer 0x%x  debug level 0x%x\n", AcpiDbgLayer, AcpiDbgLevel);
 }
 #endif
diff --git a/sys/dev/acpica/acpi_button.c b/sys/dev/acpica/acpi_button.c
index cc6b4c2..70cad56 100644
--- a/sys/dev/acpica/acpi_button.c
+++ b/sys/dev/acpica/acpi_button.c
@@ -37,6 +37,12 @@
 
 #include <dev/acpica/acpivar.h>
 
+/*
+ * Hooks for the ACPI CA debugging infrastructure
+ */
+#define _COMPONENT	SYSTEM_CONTROL
+MODULE_NAME("BUTTON")
+
 struct acpi_button_softc {
     device_t	button_dev;
     ACPI_HANDLE	button_handle;
@@ -75,17 +81,18 @@ acpi_button_probe(device_t dev)
 
     sc = device_get_softc(dev);
     if (acpi_get_type(dev) == ACPI_TYPE_DEVICE) {
-	if (acpi_MatchHid(dev, "PNP0C0C")) {
-	    device_set_desc(dev, "Control Method Power Button Device");
-	    sc->button_type = ACPI_POWER_BUTTON;
-	    return(0);
+	if (!acpi_disabled("button")) {
+	    if (acpi_MatchHid(dev, "PNP0C0C")) {
+		device_set_desc(dev, "Control Method Power Button Device");
+		sc->button_type = ACPI_POWER_BUTTON;
+		return(0);
+	    }
+	    if (acpi_MatchHid(dev, "PNP0C0E")) {
+		device_set_desc(dev, "Control Method Sleep Button Device");
+		sc->button_type = ACPI_SLEEP_BUTTON;
+		return(0);
+	    }
 	}
-	if (acpi_MatchHid(dev, "PNP0C0E")) {
-	    device_set_desc(dev, "Control Method Sleep Button Device");
-	    sc->button_type = ACPI_SLEEP_BUTTON;
-	    return(0);
-	}
-	return(ENXIO);
     }
     return(ENXIO);
 }
@@ -96,6 +103,8 @@ acpi_button_attach(device_t dev)
     struct acpi_button_softc	*sc;
     ACPI_STATUS			status;
 
+    FUNCTION_TRACE(__FUNCTION__);
+
     sc = device_get_softc(dev);
     sc->button_dev = dev;
     sc->button_handle = acpi_get_handle(dev);
@@ -103,9 +112,9 @@ acpi_button_attach(device_t dev)
     if ((status = AcpiInstallNotifyHandler(sc->button_handle, ACPI_DEVICE_NOTIFY, 
 					   acpi_button_notify_handler, sc)) != AE_OK) {
 	device_printf(sc->button_dev, "couldn't install Notify handler - %s\n", acpi_strerror(status));
-	return(ENXIO);
+	return_VALUE(ENXIO);
     }
-    return(0);
+    return_VALUE(0);
 }
 
 static void
@@ -114,10 +123,12 @@ acpi_button_notify_pressed_for_sleep(void *arg)
     struct acpi_button_softc	*sc;
     struct acpi_softc		*acpi_sc;
 
+    FUNCTION_TRACE(__FUNCTION__);
+
     sc = (struct acpi_button_softc *)arg;
     acpi_sc = acpi_device_get_parent_softc(sc->button_dev);
     if (acpi_sc == NULL) {
-	return;
+	return_VOID;
     }
 
     switch (sc->button_type) {
@@ -128,8 +139,9 @@ acpi_button_notify_pressed_for_sleep(void *arg)
 	acpi_eventhandler_sleep_button_for_sleep((void *)acpi_sc);
 	break;
     default:
-	return;		/* unknown button type */
+	break;		/* unknown button type */
     }
+    return_VOID;
 }
 
 static void
@@ -138,10 +150,12 @@ acpi_button_notify_pressed_for_wakeup(void *arg)
     struct acpi_button_softc	*sc;
     struct acpi_softc		*acpi_sc;
 
+    FUNCTION_TRACE(__FUNCTION__);
+
     sc = (struct acpi_button_softc *)arg;
     acpi_sc = acpi_device_get_parent_softc(sc->button_dev);
     if (acpi_sc == NULL) {
-	return;
+	return_VOID;
     }
 
     switch (sc->button_type) {
@@ -152,8 +166,9 @@ acpi_button_notify_pressed_for_wakeup(void *arg)
 	acpi_eventhandler_sleep_button_for_wakeup((void *)acpi_sc);
 	break;
     default:
-	return;		/* unknown button type */
+	break;		/* unknown button type */
     }
+    return_VOID;
 }
 
 /* XXX maybe not here */
@@ -165,6 +180,8 @@ acpi_button_notify_handler(ACPI_HANDLE h, UINT32 notify, void *context)
 {
     struct acpi_button_softc	*sc = (struct acpi_button_softc *)context;
 
+    FUNCTION_TRACE_U32(__FUNCTION__, notify);
+
     switch (notify) {
     case ACPI_NOTIFY_BUTTON_PRESSED_FOR_SLEEP:
 	AcpiOsQueueForExecution(OSD_PRIORITY_LO, acpi_button_notify_pressed_for_sleep, sc);
@@ -175,8 +192,9 @@ acpi_button_notify_handler(ACPI_HANDLE h, UINT32 notify, void *context)
 	device_printf(sc->button_dev, "pressed for wakeup, button type: %d\n", sc->button_type);
 	break;   
     default:
-	return;		/* unknown notification value */
+	break;		/* unknown notification value */
     }
+    return_VOID;
 }
 
 
diff --git a/sys/dev/acpica/acpi_ec.c b/sys/dev/acpica/acpi_ec.c
index ea895a2..aa90c87 100644
--- a/sys/dev/acpica/acpi_ec.c
+++ b/sys/dev/acpica/acpi_ec.c
@@ -149,6 +149,12 @@
 #include <dev/acpica/acpivar.h>
 #include <dev/acpica/acpi_ecreg.h>
 
+/*
+ * Hooks for the ACPI CA debugging infrastructure
+ */
+#define _COMPONENT	EMBEDDED_CONTROLLER
+MODULE_NAME("EC")
+
 struct acpi_ec_softc {
     device_t		ec_dev;
     ACPI_HANDLE		ec_handle;
@@ -246,9 +252,11 @@ DRIVER_MODULE(acpi_ec, acpi, acpi_ec_driver, acpi_ec_devclass, 0, 0);
 static void
 acpi_ec_identify(driver_t driver, device_t bus)
 {
-    ACPI_STATUS	Status;
+    FUNCTION_TRACE(__FUNCTION__);
 
     /* XXX implement - need an ACPI 2.0 system to test this */
+
+    return_VOID;
 }
 
 /*
@@ -258,7 +266,9 @@ acpi_ec_identify(driver_t driver, device_t bus)
 static int
 acpi_ec_probe(device_t dev)
 {
+
     if ((acpi_get_type(dev) == ACPI_TYPE_DEVICE) &&
+	!acpi_disabled("ec") &&
 	acpi_MatchHid(dev, "PNP0C09")) {
 
 	/*
@@ -280,6 +290,8 @@ acpi_ec_attach(device_t dev)
     ACPI_STATUS			Status;
     struct acpi_object_list	*args;
 
+    FUNCTION_TRACE(__FUNCTION__);
+
     /*
      * Fetch/initialise softc
      */
@@ -299,7 +311,7 @@ acpi_ec_attach(device_t dev)
     if ((sc->ec_data_res = bus_alloc_resource(sc->ec_dev, SYS_RES_IOPORT, &sc->ec_data_rid,
 					      0, ~0, 1, RF_ACTIVE)) == NULL) {
 	device_printf(dev, "can't allocate data port\n");
-	return(ENXIO);
+	return_VALUE(ENXIO);
     }
     sc->ec_data_tag = rman_get_bustag(sc->ec_data_res);
     sc->ec_data_handle = rman_get_bushandle(sc->ec_data_res);
@@ -308,7 +320,7 @@ acpi_ec_attach(device_t dev)
     if ((sc->ec_csr_res = bus_alloc_resource(sc->ec_dev, SYS_RES_IOPORT, &sc->ec_csr_rid,
 					     0, ~0, 1, RF_ACTIVE)) == NULL) {
 	device_printf(dev, "can't allocate command/status port\n");
-	return(ENXIO);
+	return_VALUE(ENXIO);
     }
     sc->ec_csr_tag = rman_get_bustag(sc->ec_csr_res);
     sc->ec_csr_handle = rman_get_bushandle(sc->ec_csr_res);
@@ -318,7 +330,7 @@ acpi_ec_attach(device_t dev)
      */
     if ((Status = AcpiOsCreateSemaphore(1, 1, &sc->ec_semaphore)) != AE_OK) {
 	device_printf(dev, "can't create semaphore - %s\n", acpi_strerror(Status));
-	return(ENXIO);
+	return_VALUE(ENXIO);
     }
 
     /*
@@ -328,15 +340,15 @@ acpi_ec_attach(device_t dev)
      * status (SCI).
      */
     if ((bufp = acpi_AllocBuffer(16)) == NULL)
-	return(ENOMEM);
+	return_VALUE(ENOMEM);
     if ((Status = AcpiEvaluateObject(sc->ec_handle, "_GPE", NULL, bufp)) != AE_OK) {
 	device_printf(dev, "can't evaluate _GPE method - %s\n", acpi_strerror(Status));
-	return(ENXIO);
+	return_VALUE(ENXIO);
     }
     param = (UINT32 *)bufp->Pointer;
     if (param[0] != ACPI_TYPE_NUMBER) {
 	device_printf(dev, "_GPE method returned bad result\n");
-	return(ENXIO);
+	return_VALUE(ENXIO);
     }
     sc->ec_gpebit = param[1];
     AcpiOsFree(bufp);
@@ -352,7 +364,7 @@ acpi_ec_attach(device_t dev)
     if ((Status = AcpiInstallGpeHandler(sc->ec_gpebit, ACPI_EVENT_LEVEL_TRIGGERED | ACPI_EVENT_EDGE_TRIGGERED, 
 					EcGpeHandler, sc)) != AE_OK) {
 	device_printf(dev, "can't install GPE handler - %s\n", acpi_strerror(Status));
-	return(ENXIO);
+	return_VALUE(ENXIO);
     }
 
     /* 
@@ -361,14 +373,14 @@ acpi_ec_attach(device_t dev)
     if ((Status = AcpiInstallAddressSpaceHandler(sc->ec_handle, ADDRESS_SPACE_EC, 
 						 &EcSpaceHandler, &EcSpaceSetup, sc)) != AE_OK) {
 	device_printf(dev, "can't install address space handler - %s\n", acpi_strerror(Status));
-	return(ENXIO);
+	return_VALUE(ENXIO);
     }
 
     /*
      * Evaluate _REG to indicate that the region is now available.
      */
     if ((args = acpi_AllocObjectList(2)) == NULL)
-	return(ENOMEM);
+	return_VALUE(ENOMEM);
     args->object[0].Type = ACPI_TYPE_NUMBER;
     args->object[0].Number.Value = ADDRESS_SPACE_EC;
     args->object[1].Type = ACPI_TYPE_NUMBER;
@@ -381,10 +393,10 @@ acpi_ec_attach(device_t dev)
      */
     if ((Status != AE_OK) && (Status != AE_NOT_FOUND)) {
 	device_printf(dev, "can't evaluate _REG method - %s\n", acpi_strerror(Status));
-	return(ENXIO);
+	return_VALUE(ENXIO);
     }
 
-    return(0);
+    return_VALUE(0);
 }
 
 static void
@@ -395,6 +407,8 @@ EcGpeHandler(void *Context)
     ACPI_STATUS			Status;
     char			qxx[5];
 
+    FUNCTION_TRACE(__FUNCTION__);
+
     for (;;) {
 
 	/*
@@ -434,6 +448,7 @@ EcGpeHandler(void *Context)
 			  qxx, acpi_strerror(Status));
 	}
     }
+    return_VOID;
 }
 
 static ACPI_STATUS
@@ -455,8 +470,10 @@ EcSpaceHandler(UINT32 Function, ACPI_PHYSICAL_ADDRESS Address, UINT32 width, UIN
     ACPI_STATUS			Status = AE_OK;
     EC_REQUEST			EcRequest;
 
+    FUNCTION_TRACE_U32(__FUNCTION__, Address);
+
     if ((Address > 0xFF) || (width != 8) || (Value == NULL) || (Context == NULL))
-        return(AE_BAD_PARAMETER);
+        return_ACPI_STATUS(AE_BAD_PARAMETER);
 
     switch (Function) {
     case ADDRESS_SPACE_READ:
@@ -473,7 +490,7 @@ EcSpaceHandler(UINT32 Function, ACPI_PHYSICAL_ADDRESS Address, UINT32 width, UIN
 
     default:
 	device_printf(sc->ec_dev, "invalid Address Space function %d\n", Function);
-        return(AE_BAD_PARAMETER);
+        return_ACPI_STATUS(AE_BAD_PARAMETER);
     }
 
     /*
@@ -482,7 +499,7 @@ EcSpaceHandler(UINT32 Function, ACPI_PHYSICAL_ADDRESS Address, UINT32 width, UIN
     if ((Status = EcTransaction(sc, &EcRequest)) == AE_OK)
         (*Value) = (UINT32)EcRequest.Data;
 
-    return(Status);
+    return_ACPI_STATUS(Status);
 }
 
 static ACPI_STATUS
diff --git a/sys/dev/acpica/acpi_isa.c b/sys/dev/acpica/acpi_isa.c
index 19d7b5f..977cf52 100644
--- a/sys/dev/acpica/acpi_isa.c
+++ b/sys/dev/acpica/acpi_isa.c
@@ -43,6 +43,12 @@
 
 #include <dev/acpica/acpivar.h>
 
+/*
+ * Hooks for the ACPI CA debugging infrastructure
+ */
+#define _COMPONENT	BUS_MANAGER
+MODULE_NAME("ISA")
+
 #define PNP_HEXTONUM(c) ((c) >= 'a'		\
 			 ? (c) - 'a' + 10	\
 			 : ((c) >= 'A'		\
@@ -136,10 +142,18 @@ acpi_isa_identify(driver_t *driver, device_t bus)
     ACPI_HANDLE		parent;
     ACPI_STATUS		status;
 
-    /*If this driver is loaded from userland ,just ignore*/
-    if(!cold){
-	    return;
-    }
+    FUNCTION_TRACE(__FUNCTION__);
+
+    if (acpi_disabled("isa"))
+	return_VOID;
+
+    /*
+     * If this driver is loaded from userland, we can assume that
+     * the ISA bus has already been detected, and we should not
+     * interfere.
+     */
+    if (!cold)
+	return_VOID;
 
     /*
      * Look for the _SB_ scope, which will contain all the devices
@@ -147,13 +161,13 @@ acpi_isa_identify(driver_t *driver, device_t bus)
      */
     if ((status = AcpiGetHandle(ACPI_ROOT_OBJECT, "\\_SB_", &parent)) != AE_OK) {
 	device_printf(bus, "no ACPI _SB_ scope - %s\n", acpi_strerror(status));
-	return;
+	return_VOID;
     }
 
-    if ((status = AcpiWalkNamespace(ACPI_TYPE_DEVICE, parent, 100, acpi_isa_identify_child, bus, NULL)) != AE_OK) {
+    if ((status = AcpiWalkNamespace(ACPI_TYPE_DEVICE, parent, 100, acpi_isa_identify_child, bus, NULL)) != AE_OK)
 	device_printf(bus, "AcpiWalkNamespace on _SB_ failed - %s\n", acpi_strerror(status));
-	return;
-    }
+
+    return_VOID;
 }
 
 /*
@@ -174,17 +188,25 @@ acpi_isa_identify_child(ACPI_HANDLE handle, UINT32 level, void *context, void **
     device_t		child, bus = (device_t)context;
     u_int32_t		devid;
 
+    FUNCTION_TRACE(__FUNCTION__);
+
+    /*
+     * Skip this node if it's on the 'avoid' list.
+     */
+    if (acpi_avoid(handle))
+	return_ACPI_STATUS(AE_OK);
+
     /*
-     * Try to get information about the device
+     * Try to get information about the device.
      */
     if (AcpiGetObjectInfo(handle, &devinfo) != AE_OK)
-	return(AE_OK);
+	return_ACPI_STATUS(AE_OK);
 
     /*
      * Reformat the _HID value into 32 bits.
      */
     if (!(devinfo.Valid & ACPI_VALID_HID))
-	return(AE_OK);
+	return_ACPI_STATUS(AE_OK);
 
     /*
      * XXX Try to avoid passing stuff to ISA that it just isn't interested
@@ -195,7 +217,7 @@ acpi_isa_identify_child(ACPI_HANDLE handle, UINT32 level, void *context, void **
      *     this is very difficult.  Maybe we need a device_configure method?
      */
     if (!(strncmp(devinfo.HardwareId, "PNP0C", 5)))
-	return(AE_OK);
+	return_ACPI_STATUS(AE_OK);
 
     devid = PNP_EISAID(devinfo.HardwareId);
 
@@ -210,7 +232,7 @@ acpi_isa_identify_child(ACPI_HANDLE handle, UINT32 level, void *context, void **
      *     point as well.
      */
     if (acpi_GetIntoBuffer(handle, AcpiGetCurrentResources, &buf) != AE_OK)
-	return(AE_OK);
+	return_ACPI_STATUS(AE_OK);
 
     /*
      * Add the device and parse our resources
@@ -225,10 +247,12 @@ acpi_isa_identify_child(ACPI_HANDLE handle, UINT32 level, void *context, void **
     if (!device_get_desc(child))
 	device_set_desc_copy(child, devinfo.HardwareId);
 
+    DEBUG_PRINT(TRACE_OBJECTS, ("added ISA PnP info for %s\n", acpi_name(handle)));
+
     /*
      * XXX Parse configuration data and _CID list to find compatible IDs
      */
-    return(AE_OK);
+    return_ACPI_STATUS(AE_OK);
 }
 
 static void
@@ -236,10 +260,14 @@ acpi_isa_set_init(device_t dev, void **context)
 {
     struct acpi_isa_context	*cp;
 
+    FUNCTION_TRACE(__FUNCTION__);
+
     cp = malloc(sizeof(*cp), M_DEVBUF, M_NOWAIT);
     bzero(cp, sizeof(*cp));
     cp->ai_nconfigs = 1;
     *context = cp;
+
+    return_VOID;
 }
 
 static void
@@ -250,8 +278,10 @@ acpi_isa_set_done(device_t dev, void *context)
     device_t			parent;
     int				i, j;
 
+    FUNCTION_TRACE(__FUNCTION__);
+
     if (cp == NULL)
-	return;
+	return_VOID;
     parent = device_get_parent(dev);
     
     /* simple config without dependants */
@@ -268,7 +298,7 @@ acpi_isa_set_done(device_t dev, void *context)
 	    if (config->ic_nmem == ISA_NMEM) {
 		device_printf(parent, "too many memory ranges\n");
 		free(configs, M_DEVBUF);
-		return;
+		return_VOID;
 	    }
 	    config->ic_mem[config->ic_nmem] = configs[0].ic_mem[j];
 	    config->ic_nmem++;
@@ -277,7 +307,7 @@ acpi_isa_set_done(device_t dev, void *context)
 	    if (config->ic_nport == ISA_NPORT) {
 		device_printf(parent, "too many port ranges\n");
 		free(configs, M_DEVBUF);
-		return;
+		return_VOID;
 	    }
 	    config->ic_port[config->ic_nport] = configs[0].ic_port[j];
 	    config->ic_nport++;
@@ -286,7 +316,7 @@ acpi_isa_set_done(device_t dev, void *context)
 	    if (config->ic_nirq == ISA_NIRQ) {
 		device_printf(parent, "too many irq ranges\n");
 		free(configs, M_DEVBUF);
-		return;
+		return_VOID;
 	    }
 	    config->ic_irqmask[config->ic_nirq] = configs[0].ic_irqmask[j];
 	    config->ic_nirq++;
@@ -295,7 +325,7 @@ acpi_isa_set_done(device_t dev, void *context)
 	    if (config->ic_ndrq == ISA_NDRQ) {
 		device_printf(parent, "too many drq ranges\n");
 		free(configs, M_DEVBUF);
-		return;
+		return_VOID;
 	    }
 	    config->ic_drqmask[config->ic_ndrq] = configs[0].ic_drqmask[j];
 	    config->ic_ndrq++;
@@ -305,6 +335,8 @@ acpi_isa_set_done(device_t dev, void *context)
 
 done:
     free(cp, M_DEVBUF);
+
+    return_VOID;
 }
 
 static void
diff --git a/sys/dev/acpica/acpi_lid.c b/sys/dev/acpica/acpi_lid.c
index b32cdc6..b93913f 100644
--- a/sys/dev/acpica/acpi_lid.c
+++ b/sys/dev/acpica/acpi_lid.c
@@ -38,6 +38,12 @@
 
 #include <dev/acpica/acpivar.h>
 
+/*
+ * Hooks for the ACPI CA debugging infrastructure
+ */
+#define _COMPONENT	SYSTEM_CONTROL
+MODULE_NAME("LID")
+
 struct acpi_lid_softc {
     device_t	lid_dev;
     ACPI_HANDLE	lid_handle;
@@ -70,6 +76,7 @@ static int
 acpi_lid_probe(device_t dev)
 {
     if ((acpi_get_type(dev) == ACPI_TYPE_DEVICE) && 
+	!acpi_disabled("lid") &&
 	acpi_MatchHid(dev, "PNP0C0D")) {
 	device_set_desc(dev, "Control Method Lid Switch");
 	return(0);
@@ -82,6 +89,8 @@ acpi_lid_attach(device_t dev)
 {
     struct acpi_lid_softc	*sc;
 
+    FUNCTION_TRACE(__FUNCTION__);
+
     sc = device_get_softc(dev);
     sc->lid_dev = dev;
     sc->lid_handle = acpi_get_handle(dev);
@@ -90,7 +99,7 @@ acpi_lid_attach(device_t dev)
      * Install notification handler
      */
     AcpiInstallNotifyHandler(sc->lid_handle, ACPI_DEVICE_NOTIFY, acpi_lid_notify_handler, sc);
-    return(0);
+    return_VALUE(0);
 }
 
 static void
@@ -101,6 +110,8 @@ acpi_lid_notify_status_changed(void *arg)
     ACPI_BUFFER			Buffer;
     ACPI_OBJECT			Object;
 
+    FUNCTION_TRACE(__FUNCTION__);
+
     sc = (struct acpi_lid_softc *)arg;
 
     /*
@@ -111,9 +122,9 @@ acpi_lid_notify_status_changed(void *arg)
     Buffer.Length = sizeof(Object);
     Buffer.Pointer = &Object;
     if (AcpiEvaluateObject(sc->lid_handle, "_LID", NULL, &Buffer) != AE_OK)
-	return;
+	return_VOID;
     if (Object.Type != ACPI_TYPE_NUMBER) 
-	return;
+	return_VOID;
 
     /*
      * Update lid status
@@ -123,7 +134,7 @@ acpi_lid_notify_status_changed(void *arg)
 
     acpi_sc = acpi_device_get_parent_softc(sc->lid_dev);
     if (acpi_sc == NULL) {
-        return;
+        return_VOID;
     }
 
     if (sc->lid_status == 0) {
@@ -131,6 +142,8 @@ acpi_lid_notify_status_changed(void *arg)
     } else {
 	EVENTHANDLER_INVOKE(acpi_wakeup_event, acpi_sc->acpi_lid_switch_sx);
     }
+
+    return_VOID;
 }
 
 /* XXX maybe not here */
@@ -141,12 +154,15 @@ acpi_lid_notify_handler(ACPI_HANDLE h, UINT32 notify, void *context)
 {
     struct acpi_lid_softc	*sc = (struct acpi_lid_softc *)context;
 
+    FUNCTION_TRACE_U32(__FUNCTION__, notify);
+
     switch (notify) {
     case ACPI_NOTIFY_STATUS_CHANGED:
 	AcpiOsQueueForExecution(OSD_PRIORITY_LO, acpi_lid_notify_status_changed, sc);
 	break;
     default:
-	return;		/* unknown notification value */
+	break;		/* unknown notification value */
     }
+    return_VOID;
 }
 
diff --git a/sys/dev/acpica/acpi_pcib.c b/sys/dev/acpica/acpi_pcib.c
index 1e7ef6e..19df2a7 100644
--- a/sys/dev/acpica/acpi_pcib.c
+++ b/sys/dev/acpica/acpi_pcib.c
@@ -39,6 +39,12 @@
 #include <pci/pcivar.h>
 #include "pcib_if.h"
 
+/*
+ * Hooks for the ACPI CA debugging infrastructure
+ */
+#define _COMPONENT	BUS_MANAGER
+MODULE_NAME("PCIB")
+
 struct acpi_pcib_softc {
     device_t		ap_dev;
     ACPI_HANDLE		ap_handle;
@@ -99,6 +105,7 @@ acpi_pcib_probe(device_t dev)
 {
 
     if ((acpi_get_type(dev) == ACPI_TYPE_DEVICE) &&
+	!acpi_disabled("pci") &&
 	acpi_MatchHid(dev, "PNP0A03")) {
 
 	/*
@@ -116,6 +123,9 @@ acpi_pcib_attach(device_t dev)
     struct acpi_pcib_softc	*sc;
     device_t			child;
     ACPI_STATUS			status;
+    int				result;
+
+    FUNCTION_TRACE(__FUNCTION__);
 
     sc = device_get_softc(dev);
     sc->ap_dev = dev;
@@ -128,7 +138,7 @@ acpi_pcib_attach(device_t dev)
      * on a hot-plug docking station, etc.
      */
     if (!acpi_DeviceIsPresent(dev))
-	return(ENXIO);
+	return_VALUE(ENXIO);
 
     /*
      * Get our segment number by evaluating _SEG
@@ -137,7 +147,7 @@ acpi_pcib_attach(device_t dev)
     if ((status = acpi_EvaluateNumber(sc->ap_handle, "_SEG", &sc->ap_segment)) != AE_OK) {
 	if (status != AE_NOT_FOUND) {
 	    device_printf(dev, "could not evaluate _SEG - %s\n", acpi_strerror(status));
-	    return(ENXIO);
+	    return_VALUE(ENXIO);
 	}
 	/* if it's not found, assume 0 */
 	sc->ap_segment = 0;
@@ -159,7 +169,7 @@ acpi_pcib_attach(device_t dev)
     if ((status = acpi_EvaluateNumber(sc->ap_handle, "_BBN", &sc->ap_bus)) != AE_OK) {
 	if (status != AE_NOT_FOUND) {
 	    device_printf(dev, "could not evaluate _BBN - %s\n", acpi_strerror(status));
-	    return(ENXIO);
+	    return_VALUE(ENXIO);
 	}
 	/* if it's not found, assume 0 */
 	sc->ap_bus = 0;
@@ -170,14 +180,14 @@ acpi_pcib_attach(device_t dev)
      * (should we complain here?).
      */
     if (devclass_get_device(devclass_find("pci"), sc->ap_bus) != NULL)
-	return(0);
+	return_VALUE(0);
 
     /*
      * Attach the PCI bus proper.
      */
     if ((child = device_add_child(dev, "pci", sc->ap_bus)) == NULL) {
 	device_printf(device_get_parent(dev), "couldn't attach pci bus");
-	return(ENXIO);
+	return_VALUE(ENXIO);
     }
 
     /*
@@ -186,7 +196,8 @@ acpi_pcib_attach(device_t dev)
      * XXX It would be nice to defer this and count on the nexus getting it
      * after the first pass, but this does not seem to be reliable.
      */
-    return(bus_generic_attach(dev));
+    result = bus_generic_attach(dev);
+    return_VALUE(result);
 }
 
 static int
diff --git a/sys/dev/acpica/acpi_pcib_acpi.c b/sys/dev/acpica/acpi_pcib_acpi.c
index 1e7ef6e..19df2a7 100644
--- a/sys/dev/acpica/acpi_pcib_acpi.c
+++ b/sys/dev/acpica/acpi_pcib_acpi.c
@@ -39,6 +39,12 @@
 #include <pci/pcivar.h>
 #include "pcib_if.h"
 
+/*
+ * Hooks for the ACPI CA debugging infrastructure
+ */
+#define _COMPONENT	BUS_MANAGER
+MODULE_NAME("PCIB")
+
 struct acpi_pcib_softc {
     device_t		ap_dev;
     ACPI_HANDLE		ap_handle;
@@ -99,6 +105,7 @@ acpi_pcib_probe(device_t dev)
 {
 
     if ((acpi_get_type(dev) == ACPI_TYPE_DEVICE) &&
+	!acpi_disabled("pci") &&
 	acpi_MatchHid(dev, "PNP0A03")) {
 
 	/*
@@ -116,6 +123,9 @@ acpi_pcib_attach(device_t dev)
     struct acpi_pcib_softc	*sc;
     device_t			child;
     ACPI_STATUS			status;
+    int				result;
+
+    FUNCTION_TRACE(__FUNCTION__);
 
     sc = device_get_softc(dev);
     sc->ap_dev = dev;
@@ -128,7 +138,7 @@ acpi_pcib_attach(device_t dev)
      * on a hot-plug docking station, etc.
      */
     if (!acpi_DeviceIsPresent(dev))
-	return(ENXIO);
+	return_VALUE(ENXIO);
 
     /*
      * Get our segment number by evaluating _SEG
@@ -137,7 +147,7 @@ acpi_pcib_attach(device_t dev)
     if ((status = acpi_EvaluateNumber(sc->ap_handle, "_SEG", &sc->ap_segment)) != AE_OK) {
 	if (status != AE_NOT_FOUND) {
 	    device_printf(dev, "could not evaluate _SEG - %s\n", acpi_strerror(status));
-	    return(ENXIO);
+	    return_VALUE(ENXIO);
 	}
 	/* if it's not found, assume 0 */
 	sc->ap_segment = 0;
@@ -159,7 +169,7 @@ acpi_pcib_attach(device_t dev)
     if ((status = acpi_EvaluateNumber(sc->ap_handle, "_BBN", &sc->ap_bus)) != AE_OK) {
 	if (status != AE_NOT_FOUND) {
 	    device_printf(dev, "could not evaluate _BBN - %s\n", acpi_strerror(status));
-	    return(ENXIO);
+	    return_VALUE(ENXIO);
 	}
 	/* if it's not found, assume 0 */
 	sc->ap_bus = 0;
@@ -170,14 +180,14 @@ acpi_pcib_attach(device_t dev)
      * (should we complain here?).
      */
     if (devclass_get_device(devclass_find("pci"), sc->ap_bus) != NULL)
-	return(0);
+	return_VALUE(0);
 
     /*
      * Attach the PCI bus proper.
      */
     if ((child = device_add_child(dev, "pci", sc->ap_bus)) == NULL) {
 	device_printf(device_get_parent(dev), "couldn't attach pci bus");
-	return(ENXIO);
+	return_VALUE(ENXIO);
     }
 
     /*
@@ -186,7 +196,8 @@ acpi_pcib_attach(device_t dev)
      * XXX It would be nice to defer this and count on the nexus getting it
      * after the first pass, but this does not seem to be reliable.
      */
-    return(bus_generic_attach(dev));
+    result = bus_generic_attach(dev);
+    return_VALUE(result);
 }
 
 static int
diff --git a/sys/dev/acpica/acpi_processor.c b/sys/dev/acpica/acpi_processor.c
index a355248..cdd13ef 100644
--- a/sys/dev/acpica/acpi_processor.c
+++ b/sys/dev/acpica/acpi_processor.c
@@ -154,6 +154,12 @@
 
 #include <dev/acpica/acpivar.h>
 
+/*
+ * Hooks for the ACPI CA debugging infrastructure
+ */
+#define _COMPONENT	PROCESSOR_CONTROL
+MODULE_NAME("PROCESSOR")
+
 #define PR_MAX_POWER_STATES		4
 #define PR_MAX_PERFORMANCE_STATES	8
 #define PR_MAX_THROTTLING_STATES	8
@@ -297,8 +303,13 @@ acpi_pr_identify(driver_t *driver, device_t bus)
 {
     ACPI_HANDLE			handle;
 
-    if (AcpiGetHandle(ACPI_ROOT_OBJECT, "\\_PR_", &handle) == AE_OK)
+    FUNCTION_TRACE(__FUNCTION__);
+
+    if (!acpi_disabled("processor") && 
+	(AcpiGetHandle(ACPI_ROOT_OBJECT, "\\_PR_", &handle) == AE_OK))
 	AcpiWalkNamespace(ACPI_TYPE_PROCESSOR, handle, 2, acpi_pr_identify_cpu, bus, NULL);
+
+    return_VOID;
 }
 
 /*
@@ -311,20 +322,21 @@ acpi_pr_identify_cpu(ACPI_HANDLE handle, UINT32 level, void *context, void **sta
     device_t		child;
     PROCESSOR_APIC	lapic;
     
+    FUNCTION_TRACE(__FUNCTION__);
 
     acpi_pr_FindLapic(bus, handle, &lapic);
 
     if (lapic.ProcessorEnabled) {
 	if ((child = BUS_ADD_CHILD(bus, 0, "acpi_pr", -1)) == NULL) {
 	    device_printf(bus, "could not create CPU device\n");
-	    return(AE_OK);
+	    return_ACPI_STATUS(AE_OK);
 	}
 	acpi_set_handle(child, handle);	
 	acpi_set_magic(child, PR_MAGIC);
 	device_set_desc(child, "processor device");
     }
 
-    return(AE_OK);
+    return_ACPI_STATUS(AE_OK);
 }
 
 static int
@@ -340,6 +352,8 @@ acpi_pr_attach(device_t dev)
 {
     struct acpi_pr_softc	*sc;
 
+    FUNCTION_TRACE(__FUNCTION__);
+
     sc = device_get_softc(dev);
     sc->pr_dev = dev;
     sc->pr_handle = acpi_get_handle(dev);
@@ -362,7 +376,7 @@ acpi_pr_attach(device_t dev)
     
     /* XXX call MD cpu-identification here? */
 
-    return(0);
+    return_VALUE(0);
 }
 
 /*
@@ -447,6 +461,8 @@ acpi_pr_CalculatePowerStates(struct acpi_pr_softc *sc)
     u_int32_t		    StateCount = 0;
     u_int32_t		    i = 0;
 
+    FUNCTION_TRACE(__FUNCTION__);
+
     /*
      * Set Latency Defaults:
      * ---------------------
@@ -467,7 +483,7 @@ acpi_pr_CalculatePowerStates(struct acpi_pr_softc *sc)
     Status = acpi_GetIntoBuffer(sc->pr_handle, AcpiGetProcessorCxInfo, &Buffer);
     if (Status != AE_OK) {
 	device_printf(sc->pr_dev, "could not fetch ProcessorCxInfo - %s\n", acpi_strerror(Status));
-	return(Status);
+	return_ACPI_STATUS(Status);
     }
 
     State = (ACPI_CX_STATE*)(Buffer.Pointer);
@@ -487,7 +503,7 @@ acpi_pr_CalculatePowerStates(struct acpi_pr_softc *sc)
     sc->pr_PowerStates.ActiveState = PR_POWER_STATE_C1;
 
     AcpiOsFree(Buffer.Pointer);
-    return(Status);
+    return_ACPI_STATUS(Status);
 }
 
 static ACPI_STATUS
@@ -495,9 +511,11 @@ acpi_pr_CalculatePerformanceStates(struct acpi_pr_softc *sc)
 {
     ACPI_STATUS		    Status = AE_OK;
 
+    FUNCTION_TRACE(__FUNCTION__);
+
     /* TODO... */
 
-    return(Status);
+    return_ACPI_STATUS(Status);
 }
     
 static ACPI_STATUS
@@ -509,6 +527,8 @@ acpi_pr_CalculateThrottlingStates(struct acpi_pr_softc *sc)
     u_int32_t		    StateCount = 0;
     u_int32_t		    i = 0;
 
+    FUNCTION_TRACE(__FUNCTION__);
+
     /*
      * Get Throttling States:
      * ----------------------
@@ -516,7 +536,7 @@ acpi_pr_CalculateThrottlingStates(struct acpi_pr_softc *sc)
     Status = acpi_GetIntoBuffer(sc->pr_handle, AcpiGetProcessorThrottlingInfo, &Buffer);
     if (Status != AE_OK) {
 	device_printf(sc->pr_dev, "could not fetch ThrottlingInfo - %s\n", acpi_strerror(Status));
-	return(Status);
+	return_ACPI_STATUS(Status);
     }
 
     State = (ACPI_CPU_THROTTLING_STATE*)(Buffer.Pointer);
@@ -535,22 +555,24 @@ acpi_pr_CalculateThrottlingStates(struct acpi_pr_softc *sc)
     }
 
     AcpiOsFree(Buffer.Pointer);
-    return(Status);
+    return_ACPI_STATUS(Status);
 }
 
 static ACPI_STATUS
 acpi_pr_PolicyInitialize(struct acpi_pr_softc *sc)
 {
-    ACPI_STATUS	status;
+    ACPI_STATUS	Status;
+
+    FUNCTION_TRACE(__FUNCTION__);
 
-    if ((status = AcpiSetProcessorSleepState(sc->pr_handle, sc->pr_PowerStates.ActiveState)) != AE_OK) {
-	device_printf(sc->pr_dev, "could not set Active sleep state - %s\n", acpi_strerror(status));
-	return(status);
+    if ((Status = AcpiSetProcessorSleepState(sc->pr_handle, sc->pr_PowerStates.ActiveState)) != AE_OK) {
+	device_printf(sc->pr_dev, "could not set Active sleep state - %s\n", acpi_strerror(Status));
+	return_ACPI_STATUS(Status);
     }
 
     /* XXX need to hook ourselves to be called when things go idle */
 /*    sc->pr_idleevent = EVENTHANDLER_FAST_REGISTER(idle_event, acpi_pr_IdleHandler, sc, IDLE_PRI_FIRST); */
-    return(AE_OK);
+    return_ACPI_STATUS(AE_OK);
 }
 
 static void
diff --git a/sys/dev/acpica/acpi_resource.c b/sys/dev/acpica/acpi_resource.c
index 3581ff7..6b848bc 100644
--- a/sys/dev/acpica/acpi_resource.c
+++ b/sys/dev/acpica/acpi_resource.c
@@ -39,6 +39,12 @@
 #include <dev/acpica/acpivar.h>
 
 /*
+ * Hooks for the ACPI CA debugging infrastructure
+ */
+#define _COMPONENT	BUS_MANAGER
+MODULE_NAME("RESOURCE")
+
+/*
  * Fetch a device's resources and associate them with the device.
  *
  * Note that it might be nice to also locate ACPI-specific resource items, such
@@ -54,18 +60,17 @@ acpi_parse_resources(device_t dev, ACPI_HANDLE handle, struct acpi_parse_resourc
     int			i;
     void		*context;
 
+    FUNCTION_TRACE(__FUNCTION__);
+
     /*
      * Fetch the device resources
      */
     if (((status = acpi_GetIntoBuffer(handle, AcpiGetPossibleResources, &buf)) != AE_OK) &&
 	((status = acpi_GetIntoBuffer(handle, AcpiGetCurrentResources, &buf)) != AE_OK)) {
 	device_printf(dev, "can't fetch ACPI resources - %s\n", acpi_strerror(status));
-	return(status);
+	return_ACPI_STATUS(status);
     }
-
-#ifdef ACPI_RES_DEBUG
-    device_printf(dev, "got %d bytes of resources\n", buf.Length);
-#endif
+    DEBUG_PRINT(TRACE_RESOURCES, ("got %d bytes of resources\n", buf.Length));
     set->set_init(dev, &context);
 
     /*
@@ -82,56 +87,42 @@ acpi_parse_resources(device_t dev, ACPI_HANDLE handle, struct acpi_parse_resourc
 	 */
 	switch(res->Id) {
 	case EndTag:
-#ifdef ACPI_RES_DEBUG
-	    device_printf(dev, "EndTag\n");
-#endif
+	    DEBUG_PRINT(TRACE_RESOURCES, ("EndTag\n"));
 	    curr = last;
 	    break;
 
 	case FixedIo:
-#ifdef ACPI_RES_DEBUG
-	    device_printf(dev, "FixedIo 0x%x/%d\n", res->Data.FixedIo.BaseAddress, res->Data.FixedIo.RangeLength);
-#endif
+	    DEBUG_PRINT(TRACE_RESOURCES, ("FixedIo 0x%x/%d\n", res->Data.FixedIo.BaseAddress, res->Data.FixedIo.RangeLength));
 	    set->set_ioport(dev, context, res->Data.FixedIo.BaseAddress, res->Data.FixedIo.RangeLength);
 	    break;
 
 	case Io:
 	    if (res->Data.Io.MinBaseAddress == res->Data.Io.MaxBaseAddress) {
-#ifdef ACPI_RES_DEBUG
-		device_printf(dev, "Io 0x%x/%d\n", res->Data.Io.MinBaseAddress, res->Data.Io.RangeLength);
-#endif
+		DEBUG_PRINT(TRACE_RESOURCES, ("Io 0x%x/%d\n", res->Data.Io.MinBaseAddress, res->Data.Io.RangeLength));
 		set->set_ioport(dev, context, res->Data.Io.MinBaseAddress, res->Data.Io.RangeLength);
 	    } else {
-#ifdef ACPI_RES_DEBUG
-		device_printf(dev, "Io 0x%x-0x%x/%d\n", res->Data.Io.MinBaseAddress, res->Data.Io.MaxBaseAddress, 
-				 res->Data.Io.RangeLength);
-#endif
+		DEBUG_PRINT(TRACE_RESOURCES, ("Io 0x%x-0x%x/%d\n", res->Data.Io.MinBaseAddress, res->Data.Io.MaxBaseAddress, 
+					      res->Data.Io.RangeLength));
 		set->set_iorange(dev, context, res->Data.Io.MinBaseAddress, res->Data.Io.MaxBaseAddress, 
 				 res->Data.Io.RangeLength, res->Data.Io.Alignment);
 	    }
 	    break;
 
 	case FixedMemory32:
-#ifdef ACPI_RES_DEBUG
-	    device_printf(dev, "FixedMemory32 0x%x/%d\n", res->Data.FixedMemory32.RangeBaseAddress, 
-			    res->Data.FixedMemory32.RangeLength);
-#endif
+	    DEBUG_PRINT(TRACE_RESOURCES, ("FixedMemory32 0x%x/%d\n", res->Data.FixedMemory32.RangeBaseAddress, 
+					  res->Data.FixedMemory32.RangeLength));
 	    set->set_memory(dev, context, res->Data.FixedMemory32.RangeBaseAddress, 
 			    res->Data.FixedMemory32.RangeLength);
 	    break;
 
 	case Memory32:
 	    if (res->Data.Memory32.MinBaseAddress == res->Data.Memory32.MaxBaseAddress) {
-#ifdef ACPI_RES_DEBUG
-		device_printf(dev, "Memory32 0x%x/%d\n", res->Data.Memory32.MinBaseAddress, 
-			      res->Data.Memory32.RangeLength);
-#endif
+		DEBUG_PRINT(TRACE_RESOURCES, ("Memory32 0x%x/%d\n", res->Data.Memory32.MinBaseAddress, 
+					      res->Data.Memory32.RangeLength));
 		set->set_memory(dev, context, res->Data.Memory32.MinBaseAddress, res->Data.Memory32.RangeLength);
 	    } else {
-#ifdef ACPI_RES_DEBUG
-		device_printf(dev, "Memory32 0x%x-0x%x/%d\n", res->Data.Memory32.MinBaseAddress, 
-			      res->Data.Memory32.MaxBaseAddress, res->Data.Memory32.RangeLength);
-#endif
+		DEBUG_PRINT(TRACE_RESOURCES, ("Memory32 0x%x-0x%x/%d\n", res->Data.Memory32.MinBaseAddress, 
+					      res->Data.Memory32.MaxBaseAddress, res->Data.Memory32.RangeLength));
 		set->set_memoryrange(dev, context, res->Data.Memory32.MinBaseAddress, res->Data.Memory32.MaxBaseAddress,
 				     res->Data.Memory32.RangeLength, res->Data.Memory32.Alignment);
 	    }
@@ -139,16 +130,12 @@ acpi_parse_resources(device_t dev, ACPI_HANDLE handle, struct acpi_parse_resourc
 
 	case Memory24:
 	    if (res->Data.Memory24.MinBaseAddress == res->Data.Memory24.MaxBaseAddress) {
-#ifdef ACPI_RES_DEBUG
-		device_printf(dev, "Memory24 0x%x/%d\n", res->Data.Memory24.MinBaseAddress, 
-			      res->Data.Memory24.RangeLength);
-#endif
+		DEBUG_PRINT(TRACE_RESOURCES, ("Memory24 0x%x/%d\n", res->Data.Memory24.MinBaseAddress, 
+					      res->Data.Memory24.RangeLength));
 		set->set_memory(dev, context, res->Data.Memory24.MinBaseAddress, res->Data.Memory24.RangeLength);
 	    } else {
-#ifdef ACPI_RES_DEBUG
-		device_printf(dev, "Memory24 0x%x-0x%x/%d\n", res->Data.Memory24.MinBaseAddress, 
-			      res->Data.Memory24.MaxBaseAddress, res->Data.Memory24.RangeLength);
-#endif
+		DEBUG_PRINT(TRACE_RESOURCES, ("Memory24 0x%x-0x%x/%d\n", res->Data.Memory24.MinBaseAddress, 
+					      res->Data.Memory24.MaxBaseAddress, res->Data.Memory24.RangeLength));
 		set->set_memoryrange(dev, context, res->Data.Memory24.MinBaseAddress, res->Data.Memory24.MaxBaseAddress,
 				     res->Data.Memory24.RangeLength, res->Data.Memory24.Alignment);
 	    }
@@ -156,50 +143,42 @@ acpi_parse_resources(device_t dev, ACPI_HANDLE handle, struct acpi_parse_resourc
 
 	case Irq:
 	    for (i = 0; i < res->Data.Irq.NumberOfInterrupts; i++) {
-#ifdef ACPI_RES_DEBUG
-		device_printf(dev, "Irq %d\n", res->Data.Irq.Interrupts[i]);
-#endif
+		DEBUG_PRINT(TRACE_RESOURCES, ("Irq %d\n", res->Data.Irq.Interrupts[i]));
 		set->set_irq(dev, context, res->Data.Irq.Interrupts[i]);
 	    }
 	    break;
 	    
 	case Dma:
 	    for (i = 0; i < res->Data.Dma.NumberOfChannels; i++) {
-#ifdef ACPI_RES_DEBUG
-		device_printf(dev, "Drq %d\n", res->Data.Dma.Channels[i]);
-#endif
+		DEBUG_PRINT(TRACE_RESOURCES, ("Drq %d\n", res->Data.Dma.Channels[i]));
 		set->set_drq(dev, context, res->Data.Dma.Channels[i]);
 	    }
 	    break;
 
 	case StartDependentFunctions:
-#ifdef ACPI_RES_DEBUG
-	    device_printf(dev, "start dependant functions");
-#endif
+	    DEBUG_PRINT(TRACE_RESOURCES, ("start dependant functions"));
 	    set->set_start_dependant(dev, context, res->Data.StartDependentFunctions.CompatibilityPriority);
 	    break;
 
 	case EndDependentFunctions:
-#ifdef ACPI_RES_DEBUG
-	    device_printf(dev, "end dependant functions");
-#endif
+	    DEBUG_PRINT(TRACE_RESOURCES, ("end dependant functions"));
 	    set->set_end_dependant(dev, context);
 	    break;
 
 	case Address32:
-	    device_printf(dev, "unimplemented Address32 resource\n");
+	    DEBUG_PRINT(TRACE_RESOURCES, ("unimplemented Address32 resource\n"));
 	    break;
 
 	case Address16:
-	    device_printf(dev, "unimplemented Address16 resource\n");
+	    DEBUG_PRINT(TRACE_RESOURCES, ("unimplemented Address16 resource\n"));
 	    break;
 
 	case ExtendedIrq:
-	    device_printf(dev, "unimplemented ExtendedIrq resource\n");
+	    DEBUG_PRINT(TRACE_RESOURCES, ("unimplemented ExtendedIrq resource\n"));
 	    break;
 
 	case VendorSpecific:
-	    device_printf(dev, "unimplemented VendorSpecific resource\n");
+	    DEBUG_PRINT(TRACE_RESOURCES, ("unimplemented VendorSpecific resource\n"));
 	    break;
 	default:
 	    break;
@@ -207,7 +186,7 @@ acpi_parse_resources(device_t dev, ACPI_HANDLE handle, struct acpi_parse_resourc
     }    
     AcpiOsFree(buf.Pointer);
     set->set_done(dev, context);
-    return(AE_OK);
+    return_ACPI_STATUS(AE_OK);
 }
 
 static void	acpi_res_set_init(device_t dev, void **context);
diff --git a/sys/dev/acpica/acpi_thermal.c b/sys/dev/acpica/acpi_thermal.c
index 45398fe..273729c 100644
--- a/sys/dev/acpica/acpi_thermal.c
+++ b/sys/dev/acpica/acpi_thermal.c
@@ -36,6 +36,12 @@
 
 #include <dev/acpica/acpivar.h>
 
+/*
+ * Hooks for the ACPI CA debugging infrastructure
+ */
+#define _COMPONENT	THERMAL_CONTROL
+MODULE_NAME("THERMAL")
+
 #define TZ_KELVTOC(x)	(((x) - 2732) / 10), (((x) - 2732) % 10)
 
 struct acpi_tz_softc {
@@ -66,11 +72,15 @@ DRIVER_MODULE(acpi_tz, acpi, acpi_tz_driver, acpi_tz_devclass, 0, 0);
 static int
 acpi_tz_probe(device_t dev)
 {
-    if (acpi_get_type(dev) == ACPI_TYPE_THERMAL) {
+
+    FUNCTION_TRACE(__FUNCTION__);
+
+    if ((acpi_get_type(dev) == ACPI_TYPE_THERMAL) &&
+	!acpi_disabled("thermal")) {
 	device_set_desc(dev, "thermal zone");
-	return(0);
+	return_VALUE(0);
     }
-    return(ENXIO);
+    return_VALUE(ENXIO);
 }
 
 static int
@@ -81,6 +91,8 @@ acpi_tz_attach(device_t dev)
     ACPI_BUFFER			buf;
     ACPI_STATUS			status;
 
+    FUNCTION_TRACE(__FUNCTION__);
+
     sc = device_get_softc(dev);
     sc->tz_dev = dev;
     sc->tz_handle = acpi_get_handle(dev);
@@ -89,14 +101,14 @@ acpi_tz_attach(device_t dev)
     buf.Length = sizeof(param);
     if ((status = AcpiEvaluateObject(sc->tz_handle, "_TMP", NULL, &buf)) != AE_OK) {
 	device_printf(sc->tz_dev, "can't fetch temperature - %s\n", acpi_strerror(status));
-	return(ENXIO);
+	return_VALUE(ENXIO);
     }
     if (param[0] != ACPI_TYPE_NUMBER) {
 	device_printf(sc->tz_dev, "%s._TMP does not evaluate to ACPI_TYPE_NUMBER\n", 
 		      acpi_name(sc->tz_handle));
-	return(ENXIO);
+	return_VALUE(ENXIO);
     }
     device_printf(sc->tz_dev, "current temperature %d.%dC\n", TZ_KELVTOC(param[1]));
     
-    return(0);
+    return_VALUE(0);
 }
diff --git a/sys/dev/acpica/acpi_timer.c b/sys/dev/acpica/acpi_timer.c
index e586aae..19ebcc0 100644
--- a/sys/dev/acpica/acpi_timer.c
+++ b/sys/dev/acpica/acpi_timer.c
@@ -36,6 +36,12 @@
 
 #include <dev/acpica/acpivar.h>
 
+/*
+ * Hooks for the ACPI CA debugging infrastructure
+ */
+#define _COMPONENT	SYSTEM_CONTROL
+MODULE_NAME("TIMER")
+
 #define ACPITIMER_MAGIC 0x524d4954	/* "TIMR" */
 
 struct acpi_timer_softc {
@@ -73,28 +79,35 @@ acpi_timer_identify(driver_t *driver, device_t parent)
     device_t			dev;
     char			desc[40];
 
+    FUNCTION_TRACE(__FUNCTION__);
+
+    if (acpi_disabled("timer"))
+	return_VOID;
+
     buf.Pointer = &fadt;
     buf.Length = sizeof(fadt);
     if ((status = AcpiGetTable(ACPI_TABLE_FADT, 1, &buf)) != AE_OK) {
 	device_printf(parent, "can't locate FADT - %s\n", acpi_strerror(status));
-	return;
+	return_VOID;
     }
     if (buf.Length != sizeof(fadt)) {
 	device_printf(parent, "invalid FADT\n");
-	return;
+	return_VOID;
     }
 
     if ((dev = BUS_ADD_CHILD(parent, 0, "acpi_timer", 0)) == NULL) {
 	device_printf(parent, "could not add acpi_timer0\n");
-	return;
+	return_VOID;
     }
     if (acpi_set_magic(dev, ACPITIMER_MAGIC)) {
 	device_printf(dev, "could not set magic\n");
-	return;
+	return_VOID;
     }
 
     sprintf(desc, "%d-bit timer at 3.579545MHz", fadt.TmrValExt ? 32 : 24);
     device_set_desc_copy(dev, desc);
+
+    return_VOID;
 }
 
 static int
@@ -110,8 +123,10 @@ acpi_timer_attach(device_t dev)
 {
     struct acpi_timer_softc		*sc;
 
+    FUNCTION_TRACE(__FUNCTION__);
+
     sc = device_get_softc(dev);
     sc->tm_dev = dev;
 
-    return(0);
+    return_VALUE(0);
 }
diff --git a/sys/dev/acpica/acpiio.h b/sys/dev/acpica/acpiio.h
index 75c59fc..2e1fb12 100644
--- a/sys/dev/acpica/acpiio.h
+++ b/sys/dev/acpica/acpiio.h
@@ -27,7 +27,14 @@
  *	$FreeBSD$
  */
 
+/*
+ * Core ACPI subsystem ioctls
+ */
 #define ACPIIO_ENABLE		_IO('P', 1)
 #define ACPIIO_DISABLE		_IO('P', 2)
 #define ACPIIO_SETSLPSTATE	_IOW('P', 3, int)
 
+#ifdef _KERNEL
+extern int	acpi_register_ioctl(u_long cmd, int (* fn)(u_long cmd, caddr_t addr, void *arg), void *arg);
+extern void	acpi_deregister_ioctl(u_long cmd, int (* fn)(u_long cmd, caddr_t addr, void *arg));
+#endif
diff --git a/sys/dev/acpica/acpivar.h b/sys/dev/acpica/acpivar.h
index f415bae..960d175 100644
--- a/sys/dev/acpica/acpivar.h
+++ b/sys/dev/acpica/acpivar.h
@@ -216,6 +216,7 @@ acpi_device_get_parent_softc(device_t child)
     return(device_get_softc(parent));
 }
 
-extern char		*acpi_name(ACPI_HANDLE handle);
-extern int		acpi_avoid(ACPI_HANDLE handle);
+extern char	*acpi_name(ACPI_HANDLE handle);
+extern int	acpi_avoid(ACPI_HANDLE handle);
+extern int	acpi_disabled(char *subsys);