Sync to my work in progress:

 - Reorder the acpi_* functions in a sensible fashion
 - Add acpi_ForeachPackageObject and acpi_GetHandleInScope
 - Use the new debugging layer/level names
 - Implement most of the guts of the acpi_thermal module; passive cooling
   isn't there yet, but active cooling should work.
 - Implement power resource handling (acpi_powerres.c)

This compiles and mostly works, but my test coverage is small, so feedback
is welcome.

4 files changed, 1092 insertions, 146 deletions

diff --git a/sys/dev/acpica/acpi.c b/sys/dev/acpica/acpi.c
index 754eac8..c3e3f76 100644
--- a/sys/dev/acpica/acpi.c
+++ b/sys/dev/acpica/acpi.c
@@ -707,6 +707,27 @@ acpi_enable_fixed_events(struct acpi_softc *sc)
 }
 
 /*
+ * Returns true if the device is actually present and should
+ * be attached to.  This requires the present, enabled, UI-visible 
+ * and diagnostics-passed bits to be set.
+ */
+BOOLEAN
+acpi_DeviceIsPresent(device_t dev)
+{
+    ACPI_HANDLE		h;
+    ACPI_DEVICE_INFO	devinfo;
+    ACPI_STATUS		error;
+    
+    if ((h = acpi_get_handle(dev)) == NULL)
+	return(FALSE);
+    if ((error = AcpiGetObjectInfo(h, &devinfo)) != AE_OK)
+	return(FALSE);
+    if ((devinfo.Valid & ACPI_VALID_HID) && (devinfo.CurrentStatus & 0xf))
+	return(TRUE);
+    return(FALSE);
+}
+
+/*
  * Match a HID string against a device
  */
 BOOLEAN
@@ -728,6 +749,46 @@ acpi_MatchHid(device_t dev, char *hid)
 }
 
 /*
+ * Return the handle of a named object within our scope, ie. that of (parent)
+ * or one if its parents.
+ */
+ACPI_STATUS
+acpi_GetHandleInScope(ACPI_HANDLE parent, char *path, ACPI_HANDLE *result)
+{
+    ACPI_HANDLE		r;
+    ACPI_STATUS		status;
+
+    /* walk back up the tree to the root */
+    for (;;) {
+	status = AcpiGetHandle(parent, path, &r);
+	if (status == AE_OK) {
+	    *result = r;
+	    return(AE_OK);
+	}
+	if (status != AE_NOT_FOUND)
+	    return(AE_OK);
+	if (AcpiGetParent(parent, &r) != AE_OK)
+	    return(AE_NOT_FOUND);
+	parent = r;
+    }
+}
+
+/*
+ * Allocate a buffer with a preset data size.
+ */
+ACPI_BUFFER *
+acpi_AllocBuffer(int size)
+{
+    ACPI_BUFFER	*buf;
+
+    if ((buf = malloc(size + sizeof(*buf), M_ACPIDEV, M_NOWAIT)) == NULL)
+	return(NULL);
+    buf->Length = size;
+    buf->Pointer = (void *)(buf + 1);
+    return(buf);
+}
+
+/*
  * Perform the tedious double-get procedure required for fetching something into
  * an ACPI_BUFFER that has not been initialised.
  */
@@ -747,20 +808,75 @@ acpi_GetIntoBuffer(ACPI_HANDLE handle, ACPI_STATUS (*func)(ACPI_HANDLE, ACPI_BUF
 }
 
 /*
- * Allocate a buffer with a preset data size.
+ * Perform the tedious double-evaluate procedure for evaluating something into
+ * an ACPI_BUFFER that has not been initialised.  Note that this evaluates
+ * twice, so avoid applying this to things that may have side-effects.
+ *
+ * This is like AcpiEvaluateObject with automatic buffer allocation.
  */
-ACPI_BUFFER *
-acpi_AllocBuffer(int size)
+ACPI_STATUS
+acpi_EvaluateIntoBuffer(ACPI_HANDLE object, ACPI_STRING pathname, ACPI_OBJECT_LIST *params,
+			ACPI_BUFFER *buf)
 {
-    ACPI_BUFFER	*buf;
+    ACPI_STATUS	status;
+    
+    buf->Length = 0;
+    buf->Pointer = NULL;
 
-    if ((buf = malloc(size + sizeof(*buf), M_ACPIDEV, M_NOWAIT)) == NULL)
-	return(NULL);
-    buf->Length = size;
-    buf->Pointer = (void *)(buf + 1);
-    return(buf);
+    if ((status = AcpiEvaluateObject(object, pathname, params, buf)) != AE_BUFFER_OVERFLOW)
+	return(status);
+    if ((buf->Pointer = AcpiOsCallocate(buf->Length)) == NULL)
+	return(AE_NO_MEMORY);
+    return(AcpiEvaluateObject(object, pathname, params, buf));
+}
+
+/*
+ * Evaluate a path that should return an integer.
+ */
+ACPI_STATUS
+acpi_EvaluateInteger(ACPI_HANDLE handle, char *path, int *number)
+{
+    ACPI_STATUS	error;
+    ACPI_BUFFER	buf;
+    ACPI_OBJECT	param;
+
+    if (handle == NULL)
+	handle = ACPI_ROOT_OBJECT;
+    buf.Pointer = &param;
+    buf.Length = sizeof(param);
+    if ((error = AcpiEvaluateObject(handle, path, NULL, &buf)) == AE_OK) {
+	if (param.Type == ACPI_TYPE_INTEGER) {
+	    *number = param.Integer.Value;
+	} else {
+	    error = AE_TYPE;
+	}
+    }
+    return(error);
+}
+
+/*
+ * Iterate over the elements of an a package object, calling the supplied
+ * function for each element.
+ *
+ * XXX possible enhancement might be to abort traversal on error.
+ */
+ACPI_STATUS
+acpi_ForeachPackageObject(ACPI_OBJECT *pkg, void (* func)(ACPI_OBJECT *comp, void *arg), void *arg)
+{
+    ACPI_OBJECT	*comp;
+    int		i;
+    
+    if ((pkg == NULL) || (pkg->Type != ACPI_TYPE_PACKAGE))
+	return(AE_BAD_PARAMETER);
+
+    /* iterate over components */
+    for (i = 0, comp = pkg->Package.Elements; i < pkg->Package.Count; i++, comp++)
+	func(comp, arg);
+
+    return(AE_OK);
 }
 
+
 static ACPI_STATUS __inline
 acpi_wakeup(UINT8 state)
 {
@@ -953,51 +1069,6 @@ acpi_Disable(struct acpi_softc *sc)
 }
 
 /*
- * Returns true if the device is actually present and should
- * be attached to.  This requires the present, enabled, UI-visible 
- * and diagnostics-passed bits to be set.
- */
-BOOLEAN
-acpi_DeviceIsPresent(device_t dev)
-{
-    ACPI_HANDLE		h;
-    ACPI_DEVICE_INFO	devinfo;
-    ACPI_STATUS		error;
-    
-    if ((h = acpi_get_handle(dev)) == NULL)
-	return(FALSE);
-    if ((error = AcpiGetObjectInfo(h, &devinfo)) != AE_OK)
-	return(FALSE);
-    if ((devinfo.Valid & ACPI_VALID_HID) && (devinfo.CurrentStatus & 0xf))
-	return(TRUE);
-    return(FALSE);
-}
-
-/*
- * Evaluate a path that should return an integer.
- */
-ACPI_STATUS
-acpi_EvaluateInteger(ACPI_HANDLE handle, char *path, int *number)
-{
-    ACPI_STATUS	error;
-    ACPI_BUFFER	buf;
-    ACPI_OBJECT	param;
-
-    if (handle == NULL)
-	handle = ACPI_ROOT_OBJECT;
-    buf.Pointer = &param;
-    buf.Length = sizeof(param);
-    if ((error = AcpiEvaluateObject(handle, path, NULL, &buf)) == AE_OK) {
-	if (param.Type == ACPI_TYPE_INTEGER) {
-	    *number = param.Integer.Value;
-	} else {
-	    error = AE_TYPE;
-	}
-    }
-    return(error);
-}
-
-/*
  * ACPI Event Handlers
  */
 
@@ -1347,63 +1418,67 @@ struct debugtag
 };
 
 static struct debugtag	dbg_layer[] = {
-    {"GLOBAL",			0x00000001},
-    {"COMMON",			0x00000002},
-    {"PARSER",			0x00000004},
-    {"DISPATCHER",		0x00000008},
-    {"INTERPRETER",		0x00000010},
-    {"NAMESPACE",		0x00000020},
-    {"RESOURCE_MANAGER",	0x00000040},
-    {"TABLE_MANAGER",		0x00000080},
-    {"EVENT_HANDLING",		0x00000100},
-    {"HARDWARE",		0x00000200},
-    {"MISCELLANEOUS",		0x00000400},
-    {"OS_DEPENDENT",		0x00000800},
-    {"BUS_MANAGER",		0x00001000},
-    {"PROCESSOR_CONTROL",	0x00002000},
-    {"SYSTEM_CONTROL",		0x00004000},
-    {"THERMAL_CONTROL",		0x00008000},
-    {"POWER_CONTROL",		0x00010000},
-    {"EMBEDDED_CONTROLLER",	0x00020000},
-    {"BATTERY",			0x00040000},
-    {"DEBUGGER",		0x00100000},
-    {"ALL_COMPONENTS",		0x001FFFFF},
+    {"ACPI_UTILITIES",		ACPI_UTILITIES},
+    {"ACPI_HARDWARE",		ACPI_HARDWARE},
+    {"ACPI_EVENTS",		ACPI_EVENTS},
+    {"ACPI_TABLES",		ACPI_TABLES},
+    {"ACPI_NAMESPACE",		ACPI_NAMESPACE},
+    {"ACPI_PARSER",		ACPI_PARSER},
+    {"ACPI_DISPATCHER",		ACPI_DISPATCHER},
+    {"ACPI_EXECUTER",		ACPI_EXECUTER},
+    {"ACPI_RESOURCES",		ACPI_RESOURCES},
+    {"ACPI_DEVICES",		ACPI_DEVICES},
+    {"ACPI_POWER",		ACPI_POWER},
+    {"ACPI_BUS_MANAGER",	ACPI_BUS_MANAGER},
+    {"ACPI_POWER_CONTROL",	ACPI_POWER_CONTROL},
+    {"ACPI_EMBEDDED_CONTROLLER", ACPI_EMBEDDED_CONTROLLER},
+    {"ACPI_PROCESSOR_CONTROL",	ACPI_PROCESSOR_CONTROL},
+    {"ACPI_AC_ADAPTER",		ACPI_AC_ADAPTER},
+    {"ACPI_BATTERY",		ACPI_BATTERY},
+    {"ACPI_BUTTON",		ACPI_BUTTON},
+    {"ACPI_SYSTEM",		ACPI_SYSTEM},
+    {"ACPI_THERMAL_ZONE",	ACPI_THERMAL_ZONE},
+    {"ACPI_DEBUGGER",		ACPI_DEBUGGER},
+    {"ACPI_OS_SERVICES",	ACPI_OS_SERVICES},
+    {"ACPI_ALL_COMPONENTS",	ACPI_ALL_COMPONENTS},
     {NULL, 0}
 };
 
 static struct debugtag dbg_level[] = {
-    {"ACPI_OK",                     0x00000001},    
-    {"ACPI_INFO",                   0x00000002},    
-    {"ACPI_WARN",                   0x00000004},    
-    {"ACPI_ERROR",                  0x00000008},    
-    {"ACPI_FATAL",                  0x00000010},    
-    {"ACPI_DEBUG_OBJECT",           0x00000020},    
-    {"ACPI_ALL",                    0x0000003F},    
-    {"TRACE_PARSE",                 0x00000100},    
-    {"TRACE_DISPATCH",              0x00000200},    
-    {"TRACE_LOAD",                  0x00000400},    
-    {"TRACE_EXEC",                  0x00000800},    
-    {"TRACE_NAMES",                 0x00001000},    
-    {"TRACE_OPREGION",              0x00002000},    
-    {"TRACE_BFIELD",                0x00004000},    
-    {"TRACE_TRASH",                 0x00008000},    
-    {"TRACE_TABLES",                0x00010000},    
-    {"TRACE_FUNCTIONS",             0x00020000},    
-    {"TRACE_VALUES",                0x00040000},    
-    {"TRACE_OBJECTS",               0x00080000},    
-    {"TRACE_ALLOCATIONS",           0x00100000},    
-    {"TRACE_RESOURCES",             0x00200000},    
-    {"TRACE_IO",                    0x00400000},    
-    {"TRACE_INTERRUPTS",            0x00800000},    
-    {"TRACE_USER_REQUESTS",         0x01000000},    
-    {"TRACE_PACKAGE",               0x02000000},    
-    {"TRACE_MUTEX",                 0x04000000},    
-    {"TRACE_ALL",                   0x0FFFFF00},    
-    {"VERBOSE_AML_DISASSEMBLE",     0x10000000},    
-    {"VERBOSE_INFO",                0x20000000},    
-    {"VERBOSE_TABLES",              0x40000000},    
-    {"VERBOSE_EVENTS",              0x80000000},    
-    {"VERBOSE_ALL",                 0xF0000000},    
+    {"ACPI_OK",			ACPI_OK},
+    {"ACPI_INFO",		ACPI_INFO},
+    {"ACPI_WARN",		ACPI_WARN},
+    {"ACPI_ERROR",		ACPI_ERROR},
+    {"ACPI_FATAL",		ACPI_FATAL},
+    {"ACPI_DEBUG_OBJECT",	ACPI_DEBUG_OBJECT},
+    {"ACPI_ALL",		ACPI_ALL},
+    {"TRACE_THREADS",		TRACE_THREADS},
+    {"TRACE_PARSE",		TRACE_PARSE},
+    {"TRACE_DISPATCH",		TRACE_DISPATCH},
+    {"TRACE_LOAD",		TRACE_LOAD},
+    {"TRACE_EXEC",		TRACE_EXEC},
+    {"TRACE_NAMES",		TRACE_NAMES},
+    {"TRACE_OPREGION",		TRACE_OPREGION},
+    {"TRACE_BFIELD",		TRACE_BFIELD},
+    {"TRACE_TRASH",		TRACE_TRASH},
+    {"TRACE_TABLES",		TRACE_TABLES},
+    {"TRACE_FUNCTIONS",		TRACE_FUNCTIONS},
+    {"TRACE_VALUES",		TRACE_VALUES},
+    {"TRACE_OBJECTS",		TRACE_OBJECTS},
+    {"TRACE_ALLOCATIONS",	TRACE_ALLOCATIONS},
+    {"TRACE_RESOURCES",		TRACE_RESOURCES},
+    {"TRACE_IO",		TRACE_IO},
+    {"TRACE_INTERRUPTS",	TRACE_INTERRUPTS},
+    {"TRACE_USER_REQUESTS",	TRACE_USER_REQUESTS},
+    {"TRACE_PACKAGE",		TRACE_PACKAGE},
+    {"TRACE_MUTEX",		TRACE_MUTEX},
+    {"TRACE_INIT",		TRACE_INIT},
+    {"TRACE_ALL",		TRACE_ALL},
+    {"VERBOSE_AML_DISASSEMBLE",	VERBOSE_AML_DISASSEMBLE},
+    {"VERBOSE_INFO",		VERBOSE_INFO},
+    {"VERBOSE_TABLES",		VERBOSE_TABLES},
+    {"VERBOSE_EVENTS",		VERBOSE_EVENTS},
+    {"VERBOSE_ALL",		VERBOSE_ALL},
     {NULL, 0}
 };    
 
diff --git a/sys/dev/acpica/acpi_powerres.c b/sys/dev/acpica/acpi_powerres.c
new file mode 100644
index 0000000..b5a4b6b
--- /dev/null
+++ b/sys/dev/acpica/acpi_powerres.c
@@ -0,0 +1,553 @@
+/*-
+ * Copyright (c) 2001 Michael Smith
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ *	$FreeBSD$
+ */
+
+#include "opt_acpi.h"		/* XXX trim includes */
+#include <sys/param.h>
+#include <sys/kernel.h>
+#include <sys/proc.h>
+#include <sys/lock.h>
+#include <sys/malloc.h>
+#include <sys/mutex.h>
+#include <sys/bus.h>
+#include <sys/conf.h>
+#include <sys/ioccom.h>
+#include <sys/reboot.h>
+#include <sys/sysctl.h>
+#include <sys/systm.h>
+#include <sys/ctype.h>
+
+#include <machine/clock.h>
+
+#include <machine/resource.h>
+
+#include "acpi.h"
+
+#include <dev/acpica/acpivar.h>
+#include <dev/acpica/acpiio.h>
+
+/*
+ * ACPI power resource management.
+ *
+ * Power resource behaviour is slightly complicated by the fact that
+ * a single power resource may provide power for more than one device.
+ * Thus, we must track the device(s) being powered by a given power
+ * resource, and only deactivate it when there are no powered devices.
+ *
+ * Note that this only manages resources for known devices.  There is an
+ * ugly case where we may turn of power to a device which is in use because
+ * we don't know that it depends on a given resource.  We should perhaps
+ * try to be smarter about this, but a more complete solution would involve
+ * scanning all of the ACPI namespace to find devices we're not currently
+ * aware of, and this raises questions about whether they should be left 
+ * on, turned off, etc.
+ *
+ * XXX locking
+ */
+
+MALLOC_DEFINE(M_ACPIPWR, "acpipwr", "ACPI power resources");
+
+/*
+ * Hooks for the ACPI CA debugging infrastructure
+ */
+#define _COMPONENT	ACPI_POWER_CONTROL
+MODULE_NAME("POWERRES")
+
+/*
+ * A relationship between a power resource and a consumer.
+ */
+struct acpi_powerreference {
+    struct acpi_powerconsumer	*ar_consumer;
+    struct acpi_powerresource	*ar_resource;
+    TAILQ_ENTRY(acpi_powerreference) ar_rlink;	/* link on resource list */
+    TAILQ_ENTRY(acpi_powerreference) ar_clink;	/* link on consumer */
+};
+    
+/*
+ * A power-managed device.
+ */
+struct acpi_powerconsumer {
+    ACPI_HANDLE		ac_consumer;		/* device which is powered */
+    int			ac_state;
+    TAILQ_ENTRY(acpi_powerconsumer) ac_link;
+    TAILQ_HEAD(,acpi_powerreference) ac_references;
+};
+
+/*
+ * A power resource.
+ */
+struct acpi_powerresource {
+    TAILQ_ENTRY(acpi_powerresource) ap_link;
+    TAILQ_HEAD(,acpi_powerreference) ap_references;
+    ACPI_HANDLE		ap_resource;		/* the resource's handle */
+    ACPI_INTEGER	ap_systemlevel;
+    ACPI_INTEGER	ap_order;
+    int			ap_state;
+#define ACPI_PWR_OFF	0
+#define ACPI_PWR_ON	1
+};
+
+TAILQ_HEAD(acpi_powerresource_list, acpi_powerresource)	acpi_powerresources;
+TAILQ_HEAD(acpi_powerconsumer_list, acpi_powerconsumer)	acpi_powerconsumers;
+
+static ACPI_STATUS		acpi_pwr_register_consumer(ACPI_HANDLE consumer);
+static ACPI_STATUS		acpi_pwr_deregister_consumer(ACPI_HANDLE consumer);
+static ACPI_STATUS		acpi_pwr_register_resource(ACPI_HANDLE res);
+static ACPI_STATUS		acpi_pwr_deregister_resource(ACPI_HANDLE res);
+static void			acpi_pwr_reference_resource(ACPI_OBJECT *obj, void *arg);
+static ACPI_STATUS		acpi_pwr_switch_power(void);
+static struct acpi_powerresource *acpi_pwr_find_resource(ACPI_HANDLE res);
+static struct acpi_powerconsumer *acpi_pwr_find_consumer(ACPI_HANDLE consumer);
+
+/*
+ * Initialise our lists.
+ */    
+static void
+acpi_pwr_init(void *junk)
+{
+    TAILQ_INIT(&acpi_powerresources);
+    TAILQ_INIT(&acpi_powerconsumers);
+}
+SYSINIT(acpi_powerresource, SI_SUB_TUNABLES, SI_ORDER_ANY, acpi_pwr_init, NULL);
+
+/*
+ * Register a power resource.
+ *
+ * It's OK to call this if we already know about the resource.
+ */
+static ACPI_STATUS
+acpi_pwr_register_resource(ACPI_HANDLE res)
+{
+    ACPI_STATUS			status;
+    ACPI_BUFFER			buf;
+    ACPI_OPERAND_OBJECT		*obj;
+    struct acpi_powerresource	*rp, *srp;
+
+    FUNCTION_TRACE(__func__);
+
+    rp = NULL;
+    obj = NULL;
+    
+    /* look to see if we know about this resource */
+    if (acpi_pwr_find_resource(res) != NULL)
+	return_ACPI_STATUS(AE_OK);		/* already know about it */
+
+    /* allocate a new resource */
+    if ((rp = malloc(sizeof(*rp), M_ACPIPWR, M_NOWAIT | M_ZERO)) == NULL) {
+	status = AE_NO_MEMORY;
+	goto out;
+    }
+    TAILQ_INIT(&rp->ap_references);
+    rp->ap_resource = res;
+
+    /* get the Power Resource object */
+    if ((status = acpi_EvaluateIntoBuffer(res, NULL, NULL, &buf)) != AE_OK) {
+	DEBUG_PRINT(TRACE_OBJECTS, ("no power resource object\n"));
+	goto out;
+    }
+    obj = buf.Pointer;
+    if (obj->Common.Type != ACPI_TYPE_POWER) {
+	DEBUG_PRINT(TRACE_OBJECTS, ("bad power resource object\n"));
+	status = AE_TYPE;
+	goto out;
+    }
+    rp->ap_systemlevel = obj->PowerResource.SystemLevel;
+    rp->ap_order = obj->PowerResource.ResourceOrder;
+    
+    /* get the current state of the resource */
+    if ((status = acpi_EvaluateInteger(rp->ap_resource, "_STA", &rp->ap_state)) != AE_OK) {
+	/* XXX is this an error? */
+	DEBUG_PRINT(TRACE_OBJECTS, ("can't get current power resource state\n"));
+	goto out;
+    }
+
+    /* sort the resource into the list */
+    status = AE_OK;
+    srp = TAILQ_FIRST(&acpi_powerresources);
+    if ((srp == NULL) || (rp->ap_order < srp->ap_order)) {
+	TAILQ_INSERT_HEAD(&acpi_powerresources, rp, ap_link);
+	goto out;
+    }
+    TAILQ_FOREACH(srp, &acpi_powerresources, ap_link)
+	if (rp->ap_order < srp->ap_order) {
+	    TAILQ_INSERT_BEFORE(srp, rp, ap_link);
+	    goto out;
+	}
+    TAILQ_INSERT_TAIL(&acpi_powerresources, rp, ap_link);
+    DEBUG_PRINT(TRACE_OBJECTS, ("registered power resource %s\n", acpi_name(res)));
+
+ out:
+    if (obj != NULL)
+	AcpiOsFree(obj);
+    if ((status != AE_OK) && (rp != NULL))
+	free(rp, M_ACPIPWR);
+    return_ACPI_STATUS(status);
+}
+
+/*
+ * Deregister a power resource.
+ */
+static ACPI_STATUS
+acpi_pwr_deregister_resource(ACPI_HANDLE res)
+{
+    struct acpi_powerresource	*rp;
+
+    FUNCTION_TRACE(__func__);
+
+    rp = NULL;
+    
+    /* find the resource */
+    if ((rp = acpi_pwr_find_resource(res)) == NULL)
+	return_ACPI_STATUS(AE_BAD_PARAMETER);
+
+    /* check that there are no consumers referencing this resource */
+    if (TAILQ_FIRST(&rp->ap_references) != NULL)
+	return_ACPI_STATUS(AE_BAD_PARAMETER);
+
+    /* pull it off the list and free it */
+    TAILQ_REMOVE(&acpi_powerresources, rp, ap_link);
+    free(rp, M_ACPIPWR);
+
+    DEBUG_PRINT(TRACE_OBJECTS, ("deregistered power resource %s\n", acpi_name(res)));
+
+    return_ACPI_STATUS(AE_OK);
+}
+
+/*
+ * Register a power consumer.  
+ *
+ * It's OK to call this if we already know about the consumer.
+ */
+static ACPI_STATUS
+acpi_pwr_register_consumer(ACPI_HANDLE consumer)
+{
+    struct acpi_powerconsumer	*pc;
+    
+    FUNCTION_TRACE(__func__);
+
+    /* check to see whether we know about this consumer already */
+    if ((pc = acpi_pwr_find_consumer(consumer)) != NULL)
+	return_ACPI_STATUS(AE_OK);
+    
+    /* allocate a new power consumer */
+    if ((pc = malloc(sizeof(*pc), M_ACPIPWR, M_NOWAIT)) == NULL)
+	return_ACPI_STATUS(AE_NO_MEMORY);
+    TAILQ_INSERT_HEAD(&acpi_powerconsumers, pc, ac_link);
+    TAILQ_INIT(&pc->ac_references);
+    pc->ac_consumer = consumer;
+
+    pc->ac_state = ACPI_STATE_UNKNOWN;	/* XXX we should try to find its current state */
+
+    DEBUG_PRINT(TRACE_OBJECTS, ("registered power consumer %s\n", acpi_name(consumer)));
+    
+    return_ACPI_STATUS(AE_OK);
+}
+
+/*
+ * Deregister a power consumer.
+ *
+ * This should only be done once the consumer has been powered off.
+ * (XXX is this correct?  Check once implemented)
+ */
+static ACPI_STATUS
+acpi_pwr_deregister_consumer(ACPI_HANDLE consumer)
+{
+    struct acpi_powerconsumer	*pc;
+    
+    FUNCTION_TRACE(__func__);
+
+    /* find the consumer */
+    if ((pc = acpi_pwr_find_consumer(consumer)) == NULL)
+	return_ACPI_STATUS(AE_BAD_PARAMETER);
+    
+    /* make sure the consumer's not referencing anything right now */
+    if (TAILQ_FIRST(&pc->ac_references) != NULL)
+	return_ACPI_STATUS(AE_BAD_PARAMETER);
+
+    /* pull the consumer off the list and free it */
+    TAILQ_REMOVE(&acpi_powerconsumers, pc, ac_link);
+
+    DEBUG_PRINT(TRACE_OBJECTS, ("deregistered power consumer %s\n", acpi_name(consumer)));
+
+    return_ACPI_STATUS(AE_OK);
+}
+
+/*
+ * Set a power consumer to a particular power state.
+ */
+ACPI_STATUS
+acpi_pwr_switch_consumer(ACPI_HANDLE consumer, int state)
+{
+    struct acpi_powerconsumer	*pc;
+    struct acpi_powerreference	*pr;
+    ACPI_HANDLE			method_handle, reslist_handle;
+    ACPI_BUFFER			reslist_buffer;
+    ACPI_OBJECT			*reslist_object;
+    ACPI_STATUS			status;
+    char			*method_name, *reslist_name;
+    int				res_changed;
+
+    FUNCTION_TRACE(__func__);
+
+    /* find the consumer */
+    if ((pc = acpi_pwr_find_consumer(consumer)) == NULL) {
+	if ((status = acpi_pwr_register_consumer(consumer)) != AE_OK)
+	    return_ACPI_STATUS(status);
+	if ((pc = acpi_pwr_find_consumer(consumer)) == NULL) {
+	    return_ACPI_STATUS(AE_ERROR);	/* something very wrong */
+	}
+    }
+
+    /* check for valid transitions */
+    if ((pc->ac_state == ACPI_STATE_D3) && (state != ACPI_STATE_D0))
+	return_ACPI_STATUS(AE_BAD_PARAMETER);	/* can only go to D0 from D3 */
+
+    /* find transition mechanism(s) */
+    switch(state) {
+    case ACPI_STATE_D0:
+	method_name = "_PS0";
+	reslist_name = "_PR0";
+	break;
+    case ACPI_STATE_D1:
+	method_name = "_PS1";
+	reslist_name = "_PR1";
+	break;
+    case ACPI_STATE_D2:
+	method_name = "_PS2";
+	reslist_name = "_PR2";
+	break;
+    case ACPI_STATE_D3:
+	method_name = "_PS3";
+	reslist_name = "_PR3";
+	break;
+    default:
+	return_ACPI_STATUS(AE_BAD_PARAMETER);
+    }
+    DEBUG_PRINT(TRACE_OBJECTS, ("setup to switch %s D%d -> D%d\n",
+				acpi_name(consumer), pc->ac_state, state));
+
+    /*
+     * Verify that this state is supported, ie. one of method or
+     * reslist must be present.  We need to do this before we go 
+     * dereferencing resources (since we might be trying to go to
+     * a state we don't support).
+     *
+     * Note that if any states are supported, the device has to
+     * support D0 and D3.  It's never an error to try to go to
+     * D0.
+     */
+    if (AcpiGetHandle(consumer, method_name, &method_handle) != AE_OK)
+	method_handle = NULL;
+    if (AcpiGetHandle(consumer, reslist_name, &reslist_handle) != AE_OK)
+	reslist_handle = NULL;
+    if ((reslist_handle == NULL) && (method_handle == NULL)) {
+	if (state == ACPI_STATE_D0) {
+	    pc->ac_state = ACPI_STATE_D0;
+	    return_ACPI_STATUS(AE_OK);
+	}
+	DEBUG_PRINT(TRACE_OBJECTS, ("attempt to set unsupported state D%d\n", 
+				    state));
+	return_ACPI_STATUS(AE_BAD_PARAMETER);
+    }
+
+    /*
+     * Check that we can actually fetch the list of power resources
+     */
+    if (reslist_handle != NULL) {
+	if ((status = acpi_EvaluateIntoBuffer(reslist_handle, NULL, NULL, &reslist_buffer)) != AE_OK) {
+	    DEBUG_PRINT(TRACE_OBJECTS, ("can't evaluate resource list %s\n",
+					acpi_name(reslist_handle)));
+	    return_ACPI_STATUS(status);
+	}
+	reslist_object = (ACPI_OBJECT *)reslist_buffer.Pointer;
+	if (reslist_object->Type != ACPI_TYPE_PACKAGE) {
+	    DEBUG_PRINT(TRACE_OBJECTS, ("resource list is not ACPI_TYPE_PACKAGE (%d)\n",
+					reslist_object->Type));
+	    return_ACPI_STATUS(AE_TYPE);
+	}
+    } else {
+	reslist_object = NULL;
+    }
+
+    /*
+     * Now we are ready to switch, so  kill off any current power resource references.
+     */
+    res_changed = 0;
+    TAILQ_FOREACH(pr, &pc->ac_references, ar_clink) {
+	TAILQ_REMOVE(&pr->ar_resource->ap_references, pr, ar_rlink);
+	res_changed = 1;
+    }
+
+    /*
+     * Add new power resource references, if we have any.  Traverse the
+     * package that we got from evaluating reslist_handle, and look up each
+     * of the resources that are referenced.
+     */
+    if (reslist_object != NULL) {
+	DEBUG_PRINT(TRACE_OBJECTS, ("referencing %d new resources\n", 
+				    reslist_object->Package.Count));
+	acpi_ForeachPackageObject(reslist_object, acpi_pwr_reference_resource, pc);
+	res_changed = 1;
+    }
+
+    /*
+     * If we changed anything in the resource list, we need to run a switch
+     * pass now.
+     */
+    if ((status = acpi_pwr_switch_power()) != AE_OK) {
+	DEBUG_PRINT(TRACE_OBJECTS, ("failed to correctly switch resources to move %s to D%d\n",
+				    acpi_name(consumer), state));
+	return_ACPI_STATUS(status);	/* XXX is this appropriate?  Should we return to previous state? */
+    }
+
+    /* invoke power state switch method (if present) */
+    if (method_handle != NULL) {
+	DEBUG_PRINT(TRACE_OBJECTS, ("invoking state transition method %s\n",
+				    acpi_name(method_handle)));
+	if ((status = AcpiEvaluateObject(method_handle, NULL, NULL, NULL)) != AE_OK)
+	    pc->ac_state = ACPI_STATE_UNKNOWN;
+	    return_ACPI_STATUS(status);	/* XXX is this appropriate?  Should we return to previous state? */
+    }
+
+    /* transition was successful */
+    pc->ac_state = state;
+    return_ACPI_STATUS(AE_OK);
+}
+
+/*
+ * Called to create a reference between a power consumer and a power resource
+ * identified in the object.
+ */
+static void
+acpi_pwr_reference_resource(ACPI_OBJECT *obj, void *arg)
+{
+    struct acpi_powerconsumer	*pc = (struct acpi_powerconsumer *)arg;
+
+    FUNCTION_TRACE(__func__);
+
+    DEBUG_PRINT(TRACE_OBJECTS, ("called to create a reference using object type %d\n",
+				obj->Type));
+
+    return_VOID;
+}
+
+
+/*
+ * Switch power resources to conform to the desired state.
+ *
+ * Consumers may have modified the power resource list in an arbitrary
+ * fashion; we sweep it in sequence order.
+ */
+static ACPI_STATUS
+acpi_pwr_switch_power(void)
+{
+    struct acpi_powerresource	*rp;
+    ACPI_STATUS			status;
+    int				cur;
+
+    FUNCTION_TRACE(__func__);
+
+    /*
+     * Sweep the list forwards turning things on.
+     */
+    TAILQ_FOREACH(rp, &acpi_powerresources, ap_link) {
+	if (rp->ap_state != ACPI_PWR_ON)
+	    continue;	/* not turning this one on */
+
+	/* we could cache this if we trusted it not to change under us */
+	if ((status = acpi_EvaluateInteger(rp->ap_resource, "_STA", &cur)) != AE_OK) {
+	    DEBUG_PRINT(TRACE_OBJECTS, ("can't get status of %s - %d\n",
+					acpi_name(rp->ap_resource), status));
+	    continue;	/* XXX is this correct?  Always switch if in doubt? */
+	}
+
+	/*
+	 * Switch if required.  Note that we ignore the result of the switch
+	 * effort; we don't know what to do if it fails, so checking wouldn't
+	 * help much.
+	 */
+	if (cur != ACPI_PWR_ON)
+	    AcpiEvaluateObject(rp->ap_resource, "_ON", NULL, NULL);
+    }
+    
+    /*
+     * Sweep the list backwards turning things off.
+     */
+    TAILQ_FOREACH_REVERSE(rp, &acpi_powerresources, acpi_powerresource_list, ap_link) {
+	if (rp->ap_state != ACPI_PWR_OFF)
+	    continue;	/* not turning this one off */
+
+	/* we could cache this if we trusted it not to change under us */
+	if ((status = acpi_EvaluateInteger(rp->ap_resource, "_STA", &cur)) != AE_OK) {
+	    DEBUG_PRINT(TRACE_OBJECTS, ("can't get status of %s - %d\n",
+					acpi_name(rp->ap_resource), status));
+	    continue;	/* XXX is this correct?  Always switch if in doubt? */
+	}
+
+	/*
+	 * Switch if required.  Note that we ignore the result of the switch
+	 * effort; we don't know what to do if it fails, so checking wouldn't
+	 * help much.
+	 */
+	if (cur != ACPI_PWR_OFF)
+	    AcpiEvaluateObject(rp->ap_resource, "_OFF", NULL, NULL);
+    }
+    return_ACPI_STATUS(AE_OK);
+}
+
+/*
+ * Find a power resource's control structure.
+ */
+static struct acpi_powerresource *
+acpi_pwr_find_resource(ACPI_HANDLE res)
+{
+    struct acpi_powerresource	*rp;
+    
+    FUNCTION_TRACE(__func__);
+
+    TAILQ_FOREACH(rp, &acpi_powerresources, ap_link)
+	if (rp->ap_resource == res)
+	    break;
+    return_VALUE(rp);
+}
+
+/*
+ * Find a power consumer's control structure.
+ */
+static struct acpi_powerconsumer *
+acpi_pwr_find_consumer(ACPI_HANDLE consumer)
+{
+    struct acpi_powerconsumer	*pc;
+    
+    FUNCTION_TRACE(__func__);
+
+    TAILQ_FOREACH(pc, &acpi_powerconsumers, ac_link)
+	if (pc->ac_consumer == consumer)
+	    break;
+    return_VALUE(pc);
+}
+
diff --git a/sys/dev/acpica/acpi_thermal.c b/sys/dev/acpica/acpi_thermal.c
index 7b3cd4e..d381b5d 100644
--- a/sys/dev/acpica/acpi_thermal.c
+++ b/sys/dev/acpica/acpi_thermal.c
@@ -1,5 +1,5 @@
 /*-
- * Copyright (c) 2000 Michael Smith
+ * Copyright (c) 2000, 2001 Michael Smith
  * Copyright (c) 2000 BSDi
  * All rights reserved.
  *
@@ -31,6 +31,7 @@
 #include <sys/param.h>
 #include <sys/kernel.h>
 #include <sys/bus.h>
+#include <sys/reboot.h>
 
 #include "acpi.h"
 
@@ -45,16 +46,50 @@ MODULE_NAME("THERMAL")
 #define TZ_ZEROC	2732
 #define TZ_KELVTOC(x)	(((x) - TZ_ZEROC) / 10), (((x) - TZ_ZEROC) % 10)
 
+#define TZ_NOTIFY_TEMPERATURE	0x80
+#define TZ_NOTIFY_DEVICES	0x81
+#define TZ_NOTIFY_LEVELS	0x82
+
+#define TZ_POLLRATE	(hz * 10)	/* every ten seconds */
+
+#define TZ_NUMLEVELS	10		/* defined by ACPI spec */
+struct acpi_tz_state {
+    int		ac[TZ_NUMLEVELS];
+    ACPI_BUFFER	al[TZ_NUMLEVELS];
+    int		crt;
+    int		hot;
+    ACPI_BUFFER	psl;
+    int		psv;
+    int		tc1;
+    int		tc2;
+    int		tsp;
+    int		tzp;
+};
+
+
 struct acpi_tz_softc {
-    device_t	tz_dev;
-    ACPI_HANDLE	tz_handle;
-    int		tz_tmp;
+    device_t			tz_dev;
+    ACPI_HANDLE			tz_handle;
+    struct callout_handle	tz_timeout;
+    int				tz_current;
+#define TZ_STATE_NONE		0
+#define TZ_STATE_PSV		1
+#define TZ_STATE_AC0		2
+#define TZ_STATE_HOT		(TZ_STATE_AC0 + TZ_NUMLEVELS)
+#define TZ_STATE_CRT		(TZ_STATE_AC0 + TZ_NUMLEVELS + 1)
+    
+    struct acpi_tz_state 	tz_state;
 };
 
 static int	acpi_tz_probe(device_t dev);
 static int	acpi_tz_attach(device_t dev);
-static void	acpi_tz_check_tripping_point(void *context);
+static int	acpi_tz_establish(struct acpi_tz_softc *sc);
+static void	acpi_tz_all_off(struct acpi_tz_softc *sc);
+static void	acpi_tz_switch_cooler_off(ACPI_OBJECT *obj, void *arg);
+static void	acpi_tz_switch_cooler_on(ACPI_OBJECT *obj, void *arg);
+static void	acpi_tz_getparam(struct acpi_tz_softc *sc, char *node, int *data);
 static void	acpi_tz_notify_handler(ACPI_HANDLE h, UINT32 notify, void *context);
+static void	acpi_tz_timeout(void *arg);
 
 static device_method_t acpi_tz_methods[] = {
     /* Device interface */
@@ -73,25 +108,31 @@ static driver_t acpi_tz_driver = {
 devclass_t acpi_tz_devclass;
 DRIVER_MODULE(acpi_tz, acpi, acpi_tz_driver, acpi_tz_devclass, 0, 0);
 
+/*
+ * Match an ACPI thermal zone.
+ */
 static int
 acpi_tz_probe(device_t dev)
 {
 
-    FUNCTION_TRACE(__func__);
+    /* no FUNCTION_TRACE - too noisy */
 
     if ((acpi_get_type(dev) == ACPI_TYPE_THERMAL) &&
 	!acpi_disabled("thermal")) {
 	device_set_desc(dev, "thermal zone");
-	return_VALUE(0);
+	return(-10);
     }
-    return_VALUE(ENXIO);
+    return(ENXIO);
 }
 
+/*
+ * Attach to an ACPI thermal zone.
+ */
 static int
 acpi_tz_attach(device_t dev)
 {
     struct acpi_tz_softc	*sc;
-    struct acpi_softc		*acpi_sc;
+    int				error;
 
     FUNCTION_TRACE(__func__);
 
@@ -99,17 +140,19 @@ acpi_tz_attach(device_t dev)
     sc->tz_dev = dev;
     sc->tz_handle = acpi_get_handle(dev);
 
+    /*
+     * Parse the current state of the thermal zone and build control
+     * structures.
+     */
+    if ((error = acpi_tz_establish(sc)) != 0)
+	return_VALUE(error);
+    
+    /*
+     * Register for any Notify events sent to this zone.
+     */
     AcpiInstallNotifyHandler(sc->tz_handle, ACPI_DEVICE_NOTIFY, 
 			     acpi_tz_notify_handler, dev);
 
-    if (device_get_unit(dev) == 0) {
-	acpi_sc = acpi_device_get_parent_softc(dev);
-	SYSCTL_ADD_UINT(&acpi_sc->acpi_sysctl_ctx,
-	    SYSCTL_CHILDREN(acpi_sc->acpi_sysctl_tree),
-	    OID_AUTO, "temperature", CTLFLAG_RD,
-	    &sc->tz_tmp, 0, "");
-    }
-
     /*
      * Don't bother evaluating/printing the temperature at this point;
      * on many systems it'll be bogus until the EC is running.
@@ -117,43 +160,306 @@ acpi_tz_attach(device_t dev)
     return_VALUE(0);
 }
 
+/*
+ * Parse the current state of this thermal zone and set up to use it.
+ *
+ * Note that we may have previous state, which will have to be discarded.
+ */
+static int
+acpi_tz_establish(struct acpi_tz_softc *sc)
+{
+    ACPI_OBJECT	*obj;
+    int		i;
+    char	nbuf[8];
+    
+    FUNCTION_TRACE(__func__);
+
+    /*
+     * Power everything off and erase any existing state.
+     */
+    acpi_tz_all_off(sc);
+    for (i = 0; i < TZ_NUMLEVELS; i++)
+	if (sc->tz_state.al[i].Pointer != NULL)
+	    AcpiOsFree(sc->tz_state.al[i].Pointer);
+    if (sc->tz_state.psl.Pointer != NULL)
+	AcpiOsFree(sc->tz_state.psl.Pointer);
+    bzero(&sc->tz_state, sizeof(sc->tz_state));
+
+    /* kill the timeout (harmless if not running */
+    untimeout(acpi_tz_timeout, sc, sc->tz_timeout);
+    
+    /*
+     * Evaluate thermal zone parameters.
+     */
+    for (i = 0; i < TZ_NUMLEVELS; i++) {
+	sprintf(nbuf, "_AC%d", i);
+	acpi_tz_getparam(sc, nbuf, &sc->tz_state.ac[i]);
+	sprintf(nbuf, "_AL%d", i);
+	acpi_EvaluateIntoBuffer(sc->tz_handle, nbuf, NULL, &sc->tz_state.al[i]);
+	obj = (ACPI_OBJECT *)sc->tz_state.al[i].Pointer;
+	if (obj != NULL) {
+	    /* should be a package containing a list of power objects */
+	    if (obj->Type != ACPI_TYPE_PACKAGE) {
+		device_printf(sc->tz_dev, "%s has unknown object type %d, rejecting\n",
+			      nbuf, obj->Type);
+		return_VALUE(ENXIO);
+	    }
+	}
+    }
+    acpi_tz_getparam(sc, "_CRT", &sc->tz_state.crt);
+    acpi_tz_getparam(sc, "_HOT", &sc->tz_state.hot);
+    acpi_EvaluateIntoBuffer(sc->tz_handle, "_PSL", NULL, &sc->tz_state.psl);
+    acpi_tz_getparam(sc, "_PSV", &sc->tz_state.psv);
+    acpi_tz_getparam(sc, "_TC1", &sc->tz_state.tc1);
+    acpi_tz_getparam(sc, "_TC2", &sc->tz_state.tc2);
+    acpi_tz_getparam(sc, "_TSP", &sc->tz_state.tsp);
+    acpi_tz_getparam(sc, "_TZP", &sc->tz_state.tzp);
+
+    /*
+     * Power off everything that we've just been given.
+     */
+    acpi_tz_all_off(sc);
+
+    /*
+     * Do we need to poll the thermal zone?  Ignore the suggested
+     * rate.
+     */
+    if (sc->tz_state.tzp != 0)
+	sc->tz_timeout = timeout(acpi_tz_timeout, sc, TZ_POLLRATE);
+	
+
+    return_VALUE(0);
+}
+
+/*
+ * Evaluate the condition of a thermal zone, take appropriate actions.
+ */
 static void
-acpi_tz_check_tripping_point(void *context)
+acpi_tz_monitor(struct acpi_tz_softc *sc)
 {
-    struct acpi_tz_softc	*sc;
-    device_t			dev = context;
-    ACPI_STATUS			status;
-    int				tp;
+    int		temp, new;
+    int		i;
 
     FUNCTION_TRACE(__func__);
 
-    sc = device_get_softc(dev);
-    if ((status =  acpi_EvaluateInteger(sc->tz_handle, "_TMP", &tp)) != AE_OK) {
-	device_printf(dev, "can't evaluate _TMP method - %s\n", acpi_strerror(status));
+    /*
+     * Get the current temperature.
+     */
+    if ((acpi_EvaluateInteger(sc->tz_handle, "_TMP", &temp)) != AE_OK) {
+	device_printf(sc->tz_dev, "error fetching current temperature\n");
+	/* XXX disable zone? go to max cooling? */
+	return_VOID;
+    }
+
+    /*
+     * Work out what we ought to be doing right now.
+     */
+    new = TZ_STATE_NONE;
+    if ((sc->tz_state.psv != -1) && (temp > sc->tz_state.psv))
+	new = TZ_STATE_PSV;
+    for (i = 0; i < TZ_NUMLEVELS; i++)
+	if ((sc->tz_state.ac[i] != -1) && (temp > sc->tz_state.ac[i]))
+	    new = TZ_STATE_AC0 + i;
+    if ((sc->tz_state.hot != -1) && (temp > sc->tz_state.hot))
+	new = TZ_STATE_HOT;
+    if ((sc->tz_state.crt != -1) && (temp > sc->tz_state.crt))
+	new = TZ_STATE_CRT;
+
+    /*
+     * If our state has not changed, do nothing.
+     */
+    if (new == sc->tz_current)
 	return_VOID;
+    
+    /*
+     * XXX if we're in a passive-cooling mode, revert to full-speed operation.
+     */
+    if (sc->tz_current == TZ_STATE_PSV) {
+	/* XXX implement */
+    }
+
+    /*
+     * If we're in an active-cooling mode, turn off the current cooler(s).
+     */
+    if ((sc->tz_current >= TZ_STATE_AC0) && (sc->tz_current < (TZ_STATE_AC0 + TZ_NUMLEVELS)))
+	acpi_ForeachPackageObject((ACPI_OBJECT *)sc->tz_state.al[sc->tz_current - TZ_STATE_AC0].Pointer,
+				  acpi_tz_switch_cooler_off, sc);
+
+    /*
+     * XXX If the new mode is passive-cooling, make appropriate adjustments.
+     */
+
+    /*
+     * If the new mode is an active-cooling mode, turn on the new cooler(s).
+     */
+    if ((new >= TZ_STATE_AC0) && (new < (TZ_STATE_AC0 + TZ_NUMLEVELS)))
+	acpi_ForeachPackageObject((ACPI_OBJECT *)sc->tz_state.al[new - TZ_STATE_AC0].Pointer,
+				  acpi_tz_switch_cooler_on, sc);
+
+    /*
+     * If we're _HOT or _CRT, shut down now!
+     */
+    if ((new == TZ_STATE_HOT) || (new == TZ_STATE_CRT)) {
+	device_printf(sc->tz_dev, "WARNING - emergency thermal shutdown in progress.\n");
+	shutdown_nice(RB_POWEROFF);
     }
+
+    /* gone to new state */
+    sc->tz_current = new;
+
+    return_VOID;
+}
+
+/*
+ * Turn off all the cooling devices.
+ */
+static void
+acpi_tz_all_off(struct acpi_tz_softc *sc)
+{
+    int		i;
+
+    FUNCTION_TRACE(__func__);
     
-    sc->tz_tmp = (tp - TZ_ZEROC) / 10;
-    if (bootverbose) {
-	device_printf(dev, "%dC\n", sc->tz_tmp);
+    /*
+     * Scan all the _AL objects, and turn them all off.
+     */
+    for (i = 0; i < TZ_NUMLEVELS; i++) {
+	if (sc->tz_state.al[i].Pointer == NULL)
+	    continue;
+	acpi_ForeachPackageObject((ACPI_OBJECT *)sc->tz_state.al[i].Pointer,
+				  acpi_tz_switch_cooler_off, sc);
     }
+
+    /*
+     * XXX revert any passive-cooling options.
+     */
+
+    sc->tz_current = TZ_STATE_NONE;
     return_VOID;
 }
 
-#define ACPI_TZ_STATUS_CHANGE 0x80
-#define ACPI_TZ_TRIPPOINT_CHANGE 0x81
+/*
+ * Given an object, verify that it's a reference to a device of some sort, 
+ * and try to switch it off.
+ */
+static void
+acpi_tz_switch_cooler_off(ACPI_OBJECT *obj, void *arg)
+{
+    struct acpi_tz_softc	*sc = (struct acpi_tz_softc *)arg;
+    ACPI_HANDLE			cooler;
+
+    FUNCTION_TRACE(__func__);
+
+    switch(obj->Type) {
+    case ACPI_TYPE_STRING:
+	DEBUG_PRINT(TRACE_OBJECTS, ("called to turn %s off\n", obj->String.Pointer));
+
+	/*
+	 * Find the handle for the device and turn it off.
+	 * The String object here seems to contain a fully-qualified path, so we
+	 * don't have to search for it in our parents.
+	 *
+	 * XXX This may not always be the case.
+	 */
+	if (AcpiGetHandle(obj->String.Pointer, NULL, &cooler) == AE_OK)
+	    acpi_pwr_switch_consumer(cooler, ACPI_STATE_D3);
+	break;
+	
+    default:
+	DEBUG_PRINT(TRACE_OBJECTS, ("called to handle unsupported object type %d\n",
+				    obj->Type));
+	break;
+    }
+	return_VOID;
+}
+
+/*
+ * Given an object, verify that it's a reference to a device of some sort, 
+ * and try to switch it on.
+ *
+ * XXX replication of off/on function code is bad, mmmkay?
+ */
+static void
+acpi_tz_switch_cooler_on(ACPI_OBJECT *obj, void *arg)
+{
+    struct acpi_tz_softc	*sc = (struct acpi_tz_softc *)arg;
+    ACPI_HANDLE			cooler, parent;
+
+    FUNCTION_TRACE(__func__);
+
+    switch(obj->Type) {
+    case ACPI_TYPE_STRING:
+	DEBUG_PRINT(TRACE_OBJECTS, ("called to turn %s off\n", obj->String.Pointer));
+
+	/* find the handle for the device and turn it off */
+	if (acpi_GetHandleInScope(sc->tz_handle, obj->String.Pointer, &cooler) == AE_OK)
+	    acpi_pwr_switch_consumer(cooler, ACPI_STATE_D0);
+	break;
+	
+    default:
+	DEBUG_PRINT(TRACE_OBJECTS, ("called to handle unsupported object type %d\n",
+				    obj->Type));
+	break;
+    }
+	return_VOID;
+}
+
+/*
+ * Read/debug-print a parameter, default it to -1.
+ */
+static void
+acpi_tz_getparam(struct acpi_tz_softc *sc, char *node, int *data)
+{
+
+    FUNCTION_TRACE(__func__);
+
+    if (acpi_EvaluateInteger(sc->tz_handle, node, data) != AE_OK) {
+	*data = -1;
+    } else {
+	DEBUG_PRINT(TRACE_VALUES, ("%s.%s = %d\n", acpi_name(sc->tz_handle),
+				   node, *data));
+    }
+    return_VOID;    
+}
+    
+/*
+ * Respond to a Notify event sent to the zone.
+ */
 static void
 acpi_tz_notify_handler(ACPI_HANDLE h, UINT32 notify, void *context)
 {
+    struct acpi_tz_softc	*sc = (struct acpi_tz_softc *)context;
+
     FUNCTION_TRACE(__func__);
 
-    switch(notify){
-    case ACPI_TZ_STATUS_CHANGE:
-    case ACPI_TZ_TRIPPOINT_CHANGE:
-	/*Check trip point*/
-	AcpiOsQueueForExecution(OSD_PRIORITY_LO, acpi_tz_check_tripping_point, context);
-	break;	
+    switch(notify) {
+    case TZ_NOTIFY_TEMPERATURE:
+	acpi_tz_monitor(sc);	/* temperature change occurred */
+	break;
+    case TZ_NOTIFY_DEVICES:
+    case TZ_NOTIFY_LEVELS:
+	acpi_tz_establish(sc);	/* zone devices/setpoints changed */
+	break;
+    default:
+	device_printf(sc->tz_dev, "unknown Notify event 0x%x\n", notify);
+	break;
     }
     return_VOID;
 }
 
+/*
+ * Poll the thermal zone.
+ */
+static void
+acpi_tz_timeout(void *arg)
+{
+    struct acpi_tz_softc	*sc = (struct acpi_tz_softc *)arg;
+
+    /* check temperature, take action */
+    acpi_tz_monitor(sc);
+
+    /* XXX passive cooling actions? */
+
+    /* re-register ourself */
+    sc->tz_timeout = timeout(acpi_tz_timeout, sc, TZ_POLLRATE);
+}
diff --git a/sys/dev/acpica/acpivar.h b/sys/dev/acpica/acpivar.h
index 4e39306..66c61d4 100644
--- a/sys/dev/acpica/acpivar.h
+++ b/sys/dev/acpica/acpivar.h
@@ -164,16 +164,23 @@ extern void		acpi_EnterDebugger(void);
 #define STEP(x)
 #endif
 
+extern BOOLEAN		acpi_DeviceIsPresent(device_t dev);
 extern BOOLEAN		acpi_MatchHid(device_t dev, char *hid);
+extern ACPI_STATUS	acpi_GetHandleInScope(ACPI_HANDLE parent, char *path, ACPI_HANDLE *result);
+extern ACPI_BUFFER	*acpi_AllocBuffer(int size);
 extern ACPI_STATUS	acpi_GetIntoBuffer(ACPI_HANDLE handle, 
 					   ACPI_STATUS (*func)(ACPI_HANDLE, ACPI_BUFFER *), 
 					   ACPI_BUFFER *buf);
-extern ACPI_BUFFER	*acpi_AllocBuffer(int size);
+extern ACPI_STATUS	acpi_EvaluateIntoBuffer(ACPI_HANDLE object, ACPI_STRING pathname,
+						ACPI_OBJECT_LIST *params, ACPI_BUFFER *buf);
+extern ACPI_STATUS	acpi_EvaluateInteger(ACPI_HANDLE handle, char *path, int *number);
+extern ACPI_STATUS	acpi_ForeachPackageObject(ACPI_OBJECT *obj, 
+						  void (* func)(ACPI_OBJECT *comp, void *arg),
+						  void *arg);
+
 extern ACPI_STATUS	acpi_SetSleepState(struct acpi_softc *sc, int state);
 extern ACPI_STATUS	acpi_Enable(struct acpi_softc *sc);
 extern ACPI_STATUS	acpi_Disable(struct acpi_softc *sc);
-extern BOOLEAN		acpi_DeviceIsPresent(device_t dev);
-extern ACPI_STATUS	acpi_EvaluateInteger(ACPI_HANDLE handle, char *path, int *number);
 
 struct acpi_parse_resource_set {
     void	(* set_init)(device_t dev, void **context);
@@ -214,6 +221,11 @@ typedef void (*acpi_event_handler_t) __P((void *, int));
 EVENTHANDLER_DECLARE(acpi_sleep_event, acpi_event_handler_t);
 EVENTHANDLER_DECLARE(acpi_wakeup_event, acpi_event_handler_t);
 
+/*
+ * Device power control.
+ */
+extern ACPI_STATUS	acpi_pwr_switch_consumer(ACPI_HANDLE consumer, int state);
+
 /* 
  * Misc. 
  */