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-rw-r--r--sys/dev/acpica/acpi_powerres.c685
1 files changed, 685 insertions, 0 deletions
diff --git a/sys/dev/acpica/acpi_powerres.c b/sys/dev/acpica/acpi_powerres.c
new file mode 100644
index 0000000..0223b32
--- /dev/null
+++ b/sys/dev/acpica/acpi_powerres.c
@@ -0,0 +1,685 @@
+/*-
+ * 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.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include "opt_acpi.h"
+#include <sys/param.h>
+#include <sys/kernel.h>
+#include <sys/malloc.h>
+#include <sys/bus.h>
+
+#include "acpi.h"
+#include <dev/acpica/acpivar.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
+ACPI_MODULE_NAME("POWERRES")
+
+/* Return values from _STA on a power resource */
+#define ACPI_PWR_OFF 0
+#define ACPI_PWR_ON 1
+
+/* 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 {
+ /* Device which is powered */
+ ACPI_HANDLE ac_consumer;
+ 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;
+ ACPI_INTEGER ap_systemlevel;
+ ACPI_INTEGER ap_order;
+};
+
+static TAILQ_HEAD(acpi_powerresource_list, acpi_powerresource)
+ acpi_powerresources;
+static 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_OBJECT *obj;
+ struct acpi_powerresource *rp, *srp;
+
+ ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
+
+ rp = NULL;
+ buf.Pointer = 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 */
+ buf.Length = ACPI_ALLOCATE_BUFFER;
+ if (ACPI_FAILURE(status = AcpiEvaluateObject(res, NULL, NULL, &buf))) {
+ ACPI_DEBUG_PRINT((ACPI_DB_OBJECTS, "no power resource object\n"));
+ goto out;
+ }
+ obj = buf.Pointer;
+ if (obj->Type != ACPI_TYPE_POWER) {
+ ACPI_DEBUG_PRINT((ACPI_DB_OBJECTS,
+ "questionable power resource object %s\n",
+ acpi_name(res)));
+ status = AE_TYPE;
+ goto out;
+ }
+ rp->ap_systemlevel = obj->PowerResource.SystemLevel;
+ rp->ap_order = obj->PowerResource.ResourceOrder;
+
+ /* 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 done;
+ }
+ TAILQ_FOREACH(srp, &acpi_powerresources, ap_link) {
+ if (rp->ap_order < srp->ap_order) {
+ TAILQ_INSERT_BEFORE(srp, rp, ap_link);
+ goto done;
+ }
+ }
+ TAILQ_INSERT_TAIL(&acpi_powerresources, rp, ap_link);
+
+ done:
+ ACPI_DEBUG_PRINT((ACPI_DB_OBJECTS,
+ "registered power resource %s\n", acpi_name(res)));
+
+ out:
+ if (buf.Pointer != NULL)
+ AcpiOsFree(buf.Pointer);
+ if (ACPI_FAILURE(status) && 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;
+
+ ACPI_FUNCTION_TRACE((char *)(uintptr_t)__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);
+
+ ACPI_DEBUG_PRINT((ACPI_DB_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;
+
+ ACPI_FUNCTION_TRACE((char *)(uintptr_t)__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;
+
+ /* XXX we should try to find its current state */
+ pc->ac_state = ACPI_STATE_UNKNOWN;
+
+ ACPI_DEBUG_PRINT((ACPI_DB_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;
+
+ ACPI_FUNCTION_TRACE((char *)(uintptr_t)__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);
+
+ ACPI_DEBUG_PRINT((ACPI_DB_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, pr0_handle;
+ ACPI_BUFFER reslist_buffer;
+ ACPI_OBJECT *reslist_object;
+ ACPI_STATUS status;
+ char *method_name, *reslist_name;
+ int res_changed;
+
+ ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
+
+ /* Find the consumer */
+ if ((pc = acpi_pwr_find_consumer(consumer)) == NULL) {
+ if (ACPI_FAILURE(status = acpi_pwr_register_consumer(consumer)))
+ 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);
+ }
+ ACPI_DEBUG_PRINT((ACPI_DB_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.
+ */
+ reslist_buffer.Pointer = NULL;
+ reslist_object = NULL;
+ if (ACPI_FAILURE(AcpiGetHandle(consumer, method_name, &method_handle)))
+ method_handle = NULL;
+ if (ACPI_FAILURE(AcpiGetHandle(consumer, reslist_name, &reslist_handle)))
+ 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);
+ }
+ if (state != ACPI_STATE_D3)
+ goto bad;
+
+ /* Turn off the resources listed in _PR0 to go to D3. */
+ if (ACPI_FAILURE(AcpiGetHandle(consumer, "_PR0", &pr0_handle)))
+ goto bad;
+ reslist_buffer.Length = ACPI_ALLOCATE_BUFFER;
+ status = AcpiEvaluateObject(pr0_handle, NULL, NULL, &reslist_buffer);
+ if (ACPI_FAILURE(status))
+ goto bad;
+ reslist_object = (ACPI_OBJECT *)reslist_buffer.Pointer;
+ if (reslist_object->Type != ACPI_TYPE_PACKAGE ||
+ reslist_object->Package.Count == 0) {
+
+ goto bad;
+ }
+ AcpiOsFree(reslist_buffer.Pointer);
+ reslist_buffer.Pointer = NULL;
+ reslist_object = NULL;
+ }
+
+ /*
+ * Check that we can actually fetch the list of power resources
+ */
+ if (reslist_handle != NULL) {
+ reslist_buffer.Length = ACPI_ALLOCATE_BUFFER;
+ status = AcpiEvaluateObject(reslist_handle, NULL, NULL,
+ &reslist_buffer);
+ if (ACPI_FAILURE(status)) {
+ ACPI_DEBUG_PRINT((ACPI_DB_OBJECTS,
+ "can't evaluate resource list %s\n",
+ acpi_name(reslist_handle)));
+ goto out;
+ }
+ reslist_object = (ACPI_OBJECT *)reslist_buffer.Pointer;
+ if (reslist_object->Type != ACPI_TYPE_PACKAGE) {
+ ACPI_DEBUG_PRINT((ACPI_DB_OBJECTS,
+ "resource list is not ACPI_TYPE_PACKAGE (%d)\n",
+ reslist_object->Type));
+ status = AE_TYPE;
+ goto out;
+ }
+ }
+
+ /*
+ * Now we are ready to switch, so kill off any current power
+ * resource references.
+ */
+ res_changed = 0;
+ while((pr = TAILQ_FIRST(&pc->ac_references)) != NULL) {
+ res_changed = 1;
+ ACPI_DEBUG_PRINT((ACPI_DB_OBJECTS, "removing reference to %s\n",
+ acpi_name(pr->ar_resource->ap_resource)));
+ TAILQ_REMOVE(&pr->ar_resource->ap_references, pr, ar_rlink);
+ TAILQ_REMOVE(&pc->ac_references, pr, ar_clink);
+ free(pr, M_ACPIPWR);
+ }
+
+ /*
+ * 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) {
+ ACPI_DEBUG_PRINT((ACPI_DB_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 (ACPI_FAILURE(status = acpi_pwr_switch_power())) {
+ ACPI_DEBUG_PRINT((ACPI_DB_OBJECTS,
+ "failed to switch resources from %s to D%d\n",
+ acpi_name(consumer), state));
+
+ /* XXX is this appropriate? Should we return to previous state? */
+ goto out;
+ }
+
+ /* Invoke power state switch method (if present) */
+ if (method_handle != NULL) {
+ ACPI_DEBUG_PRINT((ACPI_DB_OBJECTS,
+ "invoking state transition method %s\n",
+ acpi_name(method_handle)));
+ status = AcpiEvaluateObject(method_handle, NULL, NULL, NULL);
+ if (ACPI_FAILURE(status)) {
+ ACPI_DEBUG_PRINT((ACPI_DB_OBJECTS, "failed to set state - %s\n",
+ AcpiFormatException(status)));
+ pc->ac_state = ACPI_STATE_UNKNOWN;
+
+ /* XXX Should we return to previous state? */
+ goto out;
+ }
+ }
+
+ /* Transition was successful */
+ pc->ac_state = state;
+ return_ACPI_STATUS (AE_OK);
+
+ bad:
+ ACPI_DEBUG_PRINT((ACPI_DB_OBJECTS,
+ "attempt to set unsupported state D%d\n", state));
+ status = AE_BAD_PARAMETER;
+
+ out:
+ if (reslist_buffer.Pointer != NULL)
+ AcpiOsFree(reslist_buffer.Pointer);
+ return_ACPI_STATUS (status);
+}
+
+/*
+ * 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;
+ struct acpi_powerreference *pr;
+ struct acpi_powerresource *rp;
+ ACPI_HANDLE res;
+ ACPI_STATUS status;
+
+ ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
+
+ /* check the object type */
+ switch (obj->Type) {
+ case ACPI_TYPE_ANY:
+ ACPI_DEBUG_PRINT((ACPI_DB_OBJECTS, "building reference from %s to %s\n",
+ acpi_name(pc->ac_consumer),
+ acpi_name(obj->Reference.Handle)));
+ res = obj->Reference.Handle;
+ break;
+ case ACPI_TYPE_STRING:
+ ACPI_DEBUG_PRINT((ACPI_DB_OBJECTS, "building reference from %s to %s\n",
+ acpi_name(pc->ac_consumer), obj->String.Pointer));
+
+ /* Get the handle of the resource */
+ status = AcpiGetHandle(NULL, obj->String.Pointer, &res);
+ if (ACPI_FAILURE(status)) {
+ ACPI_DEBUG_PRINT((ACPI_DB_OBJECTS,
+ "couldn't find power resource %s\n",
+ obj->String.Pointer));
+ return_VOID;
+ }
+ break;
+ default:
+ ACPI_DEBUG_PRINT((ACPI_DB_OBJECTS,
+ "can't create a power reference for object type %d\n",
+ obj->Type));
+ return_VOID;
+ }
+
+ /* Create/look up the resource */
+ if (ACPI_FAILURE(status = acpi_pwr_register_resource(res))) {
+ ACPI_DEBUG_PRINT((ACPI_DB_OBJECTS,
+ "couldn't register power resource %s - %s\n",
+ obj->String.Pointer, AcpiFormatException(status)));
+ return_VOID;
+ }
+ if ((rp = acpi_pwr_find_resource(res)) == NULL) {
+ ACPI_DEBUG_PRINT((ACPI_DB_OBJECTS, "power resource list corrupted\n"));
+ return_VOID;
+ }
+ ACPI_DEBUG_PRINT((ACPI_DB_OBJECTS, "found power resource %s\n",
+ acpi_name(rp->ap_resource)));
+
+ /* Create a reference between the consumer and resource */
+ if ((pr = malloc(sizeof(*pr), M_ACPIPWR, M_NOWAIT | M_ZERO)) == NULL) {
+ ACPI_DEBUG_PRINT((ACPI_DB_OBJECTS,
+ "allocation failed for a power consumer reference\n"));
+ return_VOID;
+ }
+ pr->ar_consumer = pc;
+ pr->ar_resource = rp;
+ TAILQ_INSERT_TAIL(&pc->ac_references, pr, ar_clink);
+ TAILQ_INSERT_TAIL(&rp->ap_references, pr, ar_rlink);
+
+ 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;
+
+ ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
+
+ /*
+ * Sweep the list forwards turning things on.
+ */
+ TAILQ_FOREACH(rp, &acpi_powerresources, ap_link) {
+ if (TAILQ_FIRST(&rp->ap_references) == NULL) {
+ ACPI_DEBUG_PRINT((ACPI_DB_OBJECTS,
+ "%s has no references, not turning on\n",
+ acpi_name(rp->ap_resource)));
+ continue;
+ }
+
+ /* We could cache this if we trusted it not to change under us */
+ status = acpi_EvaluateInteger(rp->ap_resource, "_STA", &cur);
+ if (ACPI_FAILURE(status)) {
+ ACPI_DEBUG_PRINT((ACPI_DB_OBJECTS, "can't get status of %s - %d\n",
+ acpi_name(rp->ap_resource), status));
+
+ /* XXX is this correct? Always switch if in doubt? */
+ continue;
+ }
+
+ /*
+ * 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) {
+ status = AcpiEvaluateObject(rp->ap_resource, "_ON", NULL, NULL);
+ if (ACPI_FAILURE(status)) {
+ ACPI_DEBUG_PRINT((ACPI_DB_OBJECTS,
+ "failed to switch %s on - %s\n",
+ acpi_name(rp->ap_resource),
+ AcpiFormatException(status)));
+ } else {
+ ACPI_DEBUG_PRINT((ACPI_DB_OBJECTS, "switched %s on\n",
+ acpi_name(rp->ap_resource)));
+ }
+ } else {
+ ACPI_DEBUG_PRINT((ACPI_DB_OBJECTS, "%s is already on\n",
+ acpi_name(rp->ap_resource)));
+ }
+ }
+
+ /* Sweep the list backwards turning things off. */
+ TAILQ_FOREACH_REVERSE(rp, &acpi_powerresources, acpi_powerresource_list,
+ ap_link) {
+
+ if (TAILQ_FIRST(&rp->ap_references) != NULL) {
+ ACPI_DEBUG_PRINT((ACPI_DB_OBJECTS,
+ "%s has references, not turning off\n",
+ acpi_name(rp->ap_resource)));
+ continue;
+ }
+
+ /* We could cache this if we trusted it not to change under us */
+ status = acpi_EvaluateInteger(rp->ap_resource, "_STA", &cur);
+ if (ACPI_FAILURE(status)) {
+ ACPI_DEBUG_PRINT((ACPI_DB_OBJECTS, "can't get status of %s - %d\n",
+ acpi_name(rp->ap_resource), status));
+ /* XXX is this correct? Always switch if in doubt? */
+ continue;
+ }
+
+ /*
+ * 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) {
+ status = AcpiEvaluateObject(rp->ap_resource, "_OFF", NULL, NULL);
+ if (ACPI_FAILURE(status)) {
+ ACPI_DEBUG_PRINT((ACPI_DB_OBJECTS,
+ "failed to switch %s off - %s\n",
+ acpi_name(rp->ap_resource),
+ AcpiFormatException(status)));
+ } else {
+ ACPI_DEBUG_PRINT((ACPI_DB_OBJECTS, "switched %s off\n",
+ acpi_name(rp->ap_resource)));
+ }
+ } else {
+ ACPI_DEBUG_PRINT((ACPI_DB_OBJECTS, "%s is already off\n",
+ acpi_name(rp->ap_resource)));
+ }
+ }
+
+ 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;
+
+ ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
+
+ TAILQ_FOREACH(rp, &acpi_powerresources, ap_link) {
+ if (rp->ap_resource == res)
+ break;
+ }
+
+ return_PTR (rp);
+}
+
+/*
+ * Find a power consumer's control structure.
+ */
+static struct acpi_powerconsumer *
+acpi_pwr_find_consumer(ACPI_HANDLE consumer)
+{
+ struct acpi_powerconsumer *pc;
+
+ ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
+
+ TAILQ_FOREACH(pc, &acpi_powerconsumers, ac_link) {
+ if (pc->ac_consumer == consumer)
+ break;
+ }
+
+ return_PTR (pc);
+}
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