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-rw-r--r--drivers/acpi/power.c1066
1 files changed, 1066 insertions, 0 deletions
diff --git a/drivers/acpi/power.c b/drivers/acpi/power.c
new file mode 100644
index 0000000000..c2c70139c4
--- /dev/null
+++ b/drivers/acpi/power.c
@@ -0,0 +1,1066 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * drivers/acpi/power.c - ACPI Power Resources management.
+ *
+ * Copyright (C) 2001 - 2015 Intel Corp.
+ * Author: Andy Grover <andrew.grover@intel.com>
+ * Author: Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
+ * Author: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
+ */
+
+/*
+ * ACPI power-managed devices may be controlled in two ways:
+ * 1. via "Device Specific (D-State) Control"
+ * 2. via "Power Resource Control".
+ * The code below deals with ACPI Power Resources control.
+ *
+ * An ACPI "power resource object" represents a software controllable power
+ * plane, clock plane, or other resource depended on by a device.
+ *
+ * A device may rely on multiple power resources, and a power resource
+ * may be shared by multiple devices.
+ */
+
+#define pr_fmt(fmt) "ACPI: PM: " fmt
+
+#include <linux/dmi.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/types.h>
+#include <linux/slab.h>
+#include <linux/pm_runtime.h>
+#include <linux/sysfs.h>
+#include <linux/acpi.h>
+#include "sleep.h"
+#include "internal.h"
+
+#define ACPI_POWER_CLASS "power_resource"
+#define ACPI_POWER_DEVICE_NAME "Power Resource"
+#define ACPI_POWER_RESOURCE_STATE_OFF 0x00
+#define ACPI_POWER_RESOURCE_STATE_ON 0x01
+#define ACPI_POWER_RESOURCE_STATE_UNKNOWN 0xFF
+
+struct acpi_power_dependent_device {
+ struct device *dev;
+ struct list_head node;
+};
+
+struct acpi_power_resource {
+ struct acpi_device device;
+ struct list_head list_node;
+ u32 system_level;
+ u32 order;
+ unsigned int ref_count;
+ u8 state;
+ struct mutex resource_lock;
+ struct list_head dependents;
+};
+
+struct acpi_power_resource_entry {
+ struct list_head node;
+ struct acpi_power_resource *resource;
+};
+
+static LIST_HEAD(acpi_power_resource_list);
+static DEFINE_MUTEX(power_resource_list_lock);
+
+/* --------------------------------------------------------------------------
+ Power Resource Management
+ -------------------------------------------------------------------------- */
+
+static inline const char *resource_dev_name(struct acpi_power_resource *pr)
+{
+ return dev_name(&pr->device.dev);
+}
+
+static inline
+struct acpi_power_resource *to_power_resource(struct acpi_device *device)
+{
+ return container_of(device, struct acpi_power_resource, device);
+}
+
+static struct acpi_power_resource *acpi_power_get_context(acpi_handle handle)
+{
+ struct acpi_device *device = acpi_fetch_acpi_dev(handle);
+
+ if (!device)
+ return NULL;
+
+ return to_power_resource(device);
+}
+
+static int acpi_power_resources_list_add(acpi_handle handle,
+ struct list_head *list)
+{
+ struct acpi_power_resource *resource = acpi_power_get_context(handle);
+ struct acpi_power_resource_entry *entry;
+
+ if (!resource || !list)
+ return -EINVAL;
+
+ entry = kzalloc(sizeof(*entry), GFP_KERNEL);
+ if (!entry)
+ return -ENOMEM;
+
+ entry->resource = resource;
+ if (!list_empty(list)) {
+ struct acpi_power_resource_entry *e;
+
+ list_for_each_entry(e, list, node)
+ if (e->resource->order > resource->order) {
+ list_add_tail(&entry->node, &e->node);
+ return 0;
+ }
+ }
+ list_add_tail(&entry->node, list);
+ return 0;
+}
+
+void acpi_power_resources_list_free(struct list_head *list)
+{
+ struct acpi_power_resource_entry *entry, *e;
+
+ list_for_each_entry_safe(entry, e, list, node) {
+ list_del(&entry->node);
+ kfree(entry);
+ }
+}
+
+static bool acpi_power_resource_is_dup(union acpi_object *package,
+ unsigned int start, unsigned int i)
+{
+ acpi_handle rhandle, dup;
+ unsigned int j;
+
+ /* The caller is expected to check the package element types */
+ rhandle = package->package.elements[i].reference.handle;
+ for (j = start; j < i; j++) {
+ dup = package->package.elements[j].reference.handle;
+ if (dup == rhandle)
+ return true;
+ }
+
+ return false;
+}
+
+int acpi_extract_power_resources(union acpi_object *package, unsigned int start,
+ struct list_head *list)
+{
+ unsigned int i;
+ int err = 0;
+
+ for (i = start; i < package->package.count; i++) {
+ union acpi_object *element = &package->package.elements[i];
+ struct acpi_device *rdev;
+ acpi_handle rhandle;
+
+ if (element->type != ACPI_TYPE_LOCAL_REFERENCE) {
+ err = -ENODATA;
+ break;
+ }
+ rhandle = element->reference.handle;
+ if (!rhandle) {
+ err = -ENODEV;
+ break;
+ }
+
+ /* Some ACPI tables contain duplicate power resource references */
+ if (acpi_power_resource_is_dup(package, start, i))
+ continue;
+
+ rdev = acpi_add_power_resource(rhandle);
+ if (!rdev) {
+ err = -ENODEV;
+ break;
+ }
+ err = acpi_power_resources_list_add(rhandle, list);
+ if (err)
+ break;
+ }
+ if (err)
+ acpi_power_resources_list_free(list);
+
+ return err;
+}
+
+static int __get_state(acpi_handle handle, u8 *state)
+{
+ acpi_status status = AE_OK;
+ unsigned long long sta = 0;
+ u8 cur_state;
+
+ status = acpi_evaluate_integer(handle, "_STA", NULL, &sta);
+ if (ACPI_FAILURE(status))
+ return -ENODEV;
+
+ cur_state = sta & ACPI_POWER_RESOURCE_STATE_ON;
+
+ acpi_handle_debug(handle, "Power resource is %s\n",
+ cur_state ? "on" : "off");
+
+ *state = cur_state;
+ return 0;
+}
+
+static int acpi_power_get_state(struct acpi_power_resource *resource, u8 *state)
+{
+ if (resource->state == ACPI_POWER_RESOURCE_STATE_UNKNOWN) {
+ int ret;
+
+ ret = __get_state(resource->device.handle, &resource->state);
+ if (ret)
+ return ret;
+ }
+
+ *state = resource->state;
+ return 0;
+}
+
+static int acpi_power_get_list_state(struct list_head *list, u8 *state)
+{
+ struct acpi_power_resource_entry *entry;
+ u8 cur_state = ACPI_POWER_RESOURCE_STATE_OFF;
+
+ if (!list || !state)
+ return -EINVAL;
+
+ /* The state of the list is 'on' IFF all resources are 'on'. */
+ list_for_each_entry(entry, list, node) {
+ struct acpi_power_resource *resource = entry->resource;
+ int result;
+
+ mutex_lock(&resource->resource_lock);
+ result = acpi_power_get_state(resource, &cur_state);
+ mutex_unlock(&resource->resource_lock);
+ if (result)
+ return result;
+
+ if (cur_state != ACPI_POWER_RESOURCE_STATE_ON)
+ break;
+ }
+
+ pr_debug("Power resource list is %s\n", cur_state ? "on" : "off");
+
+ *state = cur_state;
+ return 0;
+}
+
+static int
+acpi_power_resource_add_dependent(struct acpi_power_resource *resource,
+ struct device *dev)
+{
+ struct acpi_power_dependent_device *dep;
+ int ret = 0;
+
+ mutex_lock(&resource->resource_lock);
+ list_for_each_entry(dep, &resource->dependents, node) {
+ /* Only add it once */
+ if (dep->dev == dev)
+ goto unlock;
+ }
+
+ dep = kzalloc(sizeof(*dep), GFP_KERNEL);
+ if (!dep) {
+ ret = -ENOMEM;
+ goto unlock;
+ }
+
+ dep->dev = dev;
+ list_add_tail(&dep->node, &resource->dependents);
+ dev_dbg(dev, "added power dependency to [%s]\n",
+ resource_dev_name(resource));
+
+unlock:
+ mutex_unlock(&resource->resource_lock);
+ return ret;
+}
+
+static void
+acpi_power_resource_remove_dependent(struct acpi_power_resource *resource,
+ struct device *dev)
+{
+ struct acpi_power_dependent_device *dep;
+
+ mutex_lock(&resource->resource_lock);
+ list_for_each_entry(dep, &resource->dependents, node) {
+ if (dep->dev == dev) {
+ list_del(&dep->node);
+ kfree(dep);
+ dev_dbg(dev, "removed power dependency to [%s]\n",
+ resource_dev_name(resource));
+ break;
+ }
+ }
+ mutex_unlock(&resource->resource_lock);
+}
+
+/**
+ * acpi_device_power_add_dependent - Add dependent device of this ACPI device
+ * @adev: ACPI device pointer
+ * @dev: Dependent device
+ *
+ * If @adev has non-empty _PR0 the @dev is added as dependent device to all
+ * power resources returned by it. This means that whenever these power
+ * resources are turned _ON the dependent devices get runtime resumed. This
+ * is needed for devices such as PCI to allow its driver to re-initialize
+ * it after it went to D0uninitialized.
+ *
+ * If @adev does not have _PR0 this does nothing.
+ *
+ * Returns %0 in case of success and negative errno otherwise.
+ */
+int acpi_device_power_add_dependent(struct acpi_device *adev,
+ struct device *dev)
+{
+ struct acpi_power_resource_entry *entry;
+ struct list_head *resources;
+ int ret;
+
+ if (!adev->flags.power_manageable)
+ return 0;
+
+ resources = &adev->power.states[ACPI_STATE_D0].resources;
+ list_for_each_entry(entry, resources, node) {
+ ret = acpi_power_resource_add_dependent(entry->resource, dev);
+ if (ret)
+ goto err;
+ }
+
+ return 0;
+
+err:
+ list_for_each_entry(entry, resources, node)
+ acpi_power_resource_remove_dependent(entry->resource, dev);
+
+ return ret;
+}
+
+/**
+ * acpi_device_power_remove_dependent - Remove dependent device
+ * @adev: ACPI device pointer
+ * @dev: Dependent device
+ *
+ * Does the opposite of acpi_device_power_add_dependent() and removes the
+ * dependent device if it is found. Can be called to @adev that does not
+ * have _PR0 as well.
+ */
+void acpi_device_power_remove_dependent(struct acpi_device *adev,
+ struct device *dev)
+{
+ struct acpi_power_resource_entry *entry;
+ struct list_head *resources;
+
+ if (!adev->flags.power_manageable)
+ return;
+
+ resources = &adev->power.states[ACPI_STATE_D0].resources;
+ list_for_each_entry_reverse(entry, resources, node)
+ acpi_power_resource_remove_dependent(entry->resource, dev);
+}
+
+static int __acpi_power_on(struct acpi_power_resource *resource)
+{
+ acpi_handle handle = resource->device.handle;
+ struct acpi_power_dependent_device *dep;
+ acpi_status status = AE_OK;
+
+ status = acpi_evaluate_object(handle, "_ON", NULL, NULL);
+ if (ACPI_FAILURE(status)) {
+ resource->state = ACPI_POWER_RESOURCE_STATE_UNKNOWN;
+ return -ENODEV;
+ }
+
+ resource->state = ACPI_POWER_RESOURCE_STATE_ON;
+
+ acpi_handle_debug(handle, "Power resource turned on\n");
+
+ /*
+ * If there are other dependents on this power resource we need to
+ * resume them now so that their drivers can re-initialize the
+ * hardware properly after it went back to D0.
+ */
+ if (list_empty(&resource->dependents) ||
+ list_is_singular(&resource->dependents))
+ return 0;
+
+ list_for_each_entry(dep, &resource->dependents, node) {
+ dev_dbg(dep->dev, "runtime resuming because [%s] turned on\n",
+ resource_dev_name(resource));
+ pm_request_resume(dep->dev);
+ }
+
+ return 0;
+}
+
+static int acpi_power_on_unlocked(struct acpi_power_resource *resource)
+{
+ int result = 0;
+
+ if (resource->ref_count++) {
+ acpi_handle_debug(resource->device.handle,
+ "Power resource already on\n");
+ } else {
+ result = __acpi_power_on(resource);
+ if (result)
+ resource->ref_count--;
+ }
+ return result;
+}
+
+static int acpi_power_on(struct acpi_power_resource *resource)
+{
+ int result;
+
+ mutex_lock(&resource->resource_lock);
+ result = acpi_power_on_unlocked(resource);
+ mutex_unlock(&resource->resource_lock);
+ return result;
+}
+
+static int __acpi_power_off(struct acpi_power_resource *resource)
+{
+ acpi_handle handle = resource->device.handle;
+ acpi_status status;
+
+ status = acpi_evaluate_object(handle, "_OFF", NULL, NULL);
+ if (ACPI_FAILURE(status)) {
+ resource->state = ACPI_POWER_RESOURCE_STATE_UNKNOWN;
+ return -ENODEV;
+ }
+
+ resource->state = ACPI_POWER_RESOURCE_STATE_OFF;
+
+ acpi_handle_debug(handle, "Power resource turned off\n");
+
+ return 0;
+}
+
+static int acpi_power_off_unlocked(struct acpi_power_resource *resource)
+{
+ int result = 0;
+
+ if (!resource->ref_count) {
+ acpi_handle_debug(resource->device.handle,
+ "Power resource already off\n");
+ return 0;
+ }
+
+ if (--resource->ref_count) {
+ acpi_handle_debug(resource->device.handle,
+ "Power resource still in use\n");
+ } else {
+ result = __acpi_power_off(resource);
+ if (result)
+ resource->ref_count++;
+ }
+ return result;
+}
+
+static int acpi_power_off(struct acpi_power_resource *resource)
+{
+ int result;
+
+ mutex_lock(&resource->resource_lock);
+ result = acpi_power_off_unlocked(resource);
+ mutex_unlock(&resource->resource_lock);
+ return result;
+}
+
+static int acpi_power_off_list(struct list_head *list)
+{
+ struct acpi_power_resource_entry *entry;
+ int result = 0;
+
+ list_for_each_entry_reverse(entry, list, node) {
+ result = acpi_power_off(entry->resource);
+ if (result)
+ goto err;
+ }
+ return 0;
+
+ err:
+ list_for_each_entry_continue(entry, list, node)
+ acpi_power_on(entry->resource);
+
+ return result;
+}
+
+static int acpi_power_on_list(struct list_head *list)
+{
+ struct acpi_power_resource_entry *entry;
+ int result = 0;
+
+ list_for_each_entry(entry, list, node) {
+ result = acpi_power_on(entry->resource);
+ if (result)
+ goto err;
+ }
+ return 0;
+
+ err:
+ list_for_each_entry_continue_reverse(entry, list, node)
+ acpi_power_off(entry->resource);
+
+ return result;
+}
+
+static struct attribute *attrs[] = {
+ NULL,
+};
+
+static const struct attribute_group attr_groups[] = {
+ [ACPI_STATE_D0] = {
+ .name = "power_resources_D0",
+ .attrs = attrs,
+ },
+ [ACPI_STATE_D1] = {
+ .name = "power_resources_D1",
+ .attrs = attrs,
+ },
+ [ACPI_STATE_D2] = {
+ .name = "power_resources_D2",
+ .attrs = attrs,
+ },
+ [ACPI_STATE_D3_HOT] = {
+ .name = "power_resources_D3hot",
+ .attrs = attrs,
+ },
+};
+
+static const struct attribute_group wakeup_attr_group = {
+ .name = "power_resources_wakeup",
+ .attrs = attrs,
+};
+
+static void acpi_power_hide_list(struct acpi_device *adev,
+ struct list_head *resources,
+ const struct attribute_group *attr_group)
+{
+ struct acpi_power_resource_entry *entry;
+
+ if (list_empty(resources))
+ return;
+
+ list_for_each_entry_reverse(entry, resources, node) {
+ struct acpi_device *res_dev = &entry->resource->device;
+
+ sysfs_remove_link_from_group(&adev->dev.kobj,
+ attr_group->name,
+ dev_name(&res_dev->dev));
+ }
+ sysfs_remove_group(&adev->dev.kobj, attr_group);
+}
+
+static void acpi_power_expose_list(struct acpi_device *adev,
+ struct list_head *resources,
+ const struct attribute_group *attr_group)
+{
+ struct acpi_power_resource_entry *entry;
+ int ret;
+
+ if (list_empty(resources))
+ return;
+
+ ret = sysfs_create_group(&adev->dev.kobj, attr_group);
+ if (ret)
+ return;
+
+ list_for_each_entry(entry, resources, node) {
+ struct acpi_device *res_dev = &entry->resource->device;
+
+ ret = sysfs_add_link_to_group(&adev->dev.kobj,
+ attr_group->name,
+ &res_dev->dev.kobj,
+ dev_name(&res_dev->dev));
+ if (ret) {
+ acpi_power_hide_list(adev, resources, attr_group);
+ break;
+ }
+ }
+}
+
+static void acpi_power_expose_hide(struct acpi_device *adev,
+ struct list_head *resources,
+ const struct attribute_group *attr_group,
+ bool expose)
+{
+ if (expose)
+ acpi_power_expose_list(adev, resources, attr_group);
+ else
+ acpi_power_hide_list(adev, resources, attr_group);
+}
+
+void acpi_power_add_remove_device(struct acpi_device *adev, bool add)
+{
+ int state;
+
+ if (adev->wakeup.flags.valid)
+ acpi_power_expose_hide(adev, &adev->wakeup.resources,
+ &wakeup_attr_group, add);
+
+ if (!adev->power.flags.power_resources)
+ return;
+
+ for (state = ACPI_STATE_D0; state <= ACPI_STATE_D3_HOT; state++)
+ acpi_power_expose_hide(adev,
+ &adev->power.states[state].resources,
+ &attr_groups[state], add);
+}
+
+int acpi_power_wakeup_list_init(struct list_head *list, int *system_level_p)
+{
+ struct acpi_power_resource_entry *entry;
+ int system_level = 5;
+
+ list_for_each_entry(entry, list, node) {
+ struct acpi_power_resource *resource = entry->resource;
+ u8 state;
+
+ mutex_lock(&resource->resource_lock);
+
+ /*
+ * Make sure that the power resource state and its reference
+ * counter value are consistent with each other.
+ */
+ if (!resource->ref_count &&
+ !acpi_power_get_state(resource, &state) &&
+ state == ACPI_POWER_RESOURCE_STATE_ON)
+ __acpi_power_off(resource);
+
+ if (system_level > resource->system_level)
+ system_level = resource->system_level;
+
+ mutex_unlock(&resource->resource_lock);
+ }
+ *system_level_p = system_level;
+ return 0;
+}
+
+/* --------------------------------------------------------------------------
+ Device Power Management
+ -------------------------------------------------------------------------- */
+
+/**
+ * acpi_device_sleep_wake - execute _DSW (Device Sleep Wake) or (deprecated in
+ * ACPI 3.0) _PSW (Power State Wake)
+ * @dev: Device to handle.
+ * @enable: 0 - disable, 1 - enable the wake capabilities of the device.
+ * @sleep_state: Target sleep state of the system.
+ * @dev_state: Target power state of the device.
+ *
+ * Execute _DSW (Device Sleep Wake) or (deprecated in ACPI 3.0) _PSW (Power
+ * State Wake) for the device, if present. On failure reset the device's
+ * wakeup.flags.valid flag.
+ *
+ * RETURN VALUE:
+ * 0 if either _DSW or _PSW has been successfully executed
+ * 0 if neither _DSW nor _PSW has been found
+ * -ENODEV if the execution of either _DSW or _PSW has failed
+ */
+int acpi_device_sleep_wake(struct acpi_device *dev,
+ int enable, int sleep_state, int dev_state)
+{
+ union acpi_object in_arg[3];
+ struct acpi_object_list arg_list = { 3, in_arg };
+ acpi_status status = AE_OK;
+
+ /*
+ * Try to execute _DSW first.
+ *
+ * Three arguments are needed for the _DSW object:
+ * Argument 0: enable/disable the wake capabilities
+ * Argument 1: target system state
+ * Argument 2: target device state
+ * When _DSW object is called to disable the wake capabilities, maybe
+ * the first argument is filled. The values of the other two arguments
+ * are meaningless.
+ */
+ in_arg[0].type = ACPI_TYPE_INTEGER;
+ in_arg[0].integer.value = enable;
+ in_arg[1].type = ACPI_TYPE_INTEGER;
+ in_arg[1].integer.value = sleep_state;
+ in_arg[2].type = ACPI_TYPE_INTEGER;
+ in_arg[2].integer.value = dev_state;
+ status = acpi_evaluate_object(dev->handle, "_DSW", &arg_list, NULL);
+ if (ACPI_SUCCESS(status)) {
+ return 0;
+ } else if (status != AE_NOT_FOUND) {
+ acpi_handle_info(dev->handle, "_DSW execution failed\n");
+ dev->wakeup.flags.valid = 0;
+ return -ENODEV;
+ }
+
+ /* Execute _PSW */
+ status = acpi_execute_simple_method(dev->handle, "_PSW", enable);
+ if (ACPI_FAILURE(status) && (status != AE_NOT_FOUND)) {
+ acpi_handle_info(dev->handle, "_PSW execution failed\n");
+ dev->wakeup.flags.valid = 0;
+ return -ENODEV;
+ }
+
+ return 0;
+}
+
+/*
+ * Prepare a wakeup device, two steps (Ref ACPI 2.0:P229):
+ * 1. Power on the power resources required for the wakeup device
+ * 2. Execute _DSW (Device Sleep Wake) or (deprecated in ACPI 3.0) _PSW (Power
+ * State Wake) for the device, if present
+ */
+int acpi_enable_wakeup_device_power(struct acpi_device *dev, int sleep_state)
+{
+ int err = 0;
+
+ if (!dev || !dev->wakeup.flags.valid)
+ return -EINVAL;
+
+ mutex_lock(&acpi_device_lock);
+
+ dev_dbg(&dev->dev, "Enabling wakeup power (count %d)\n",
+ dev->wakeup.prepare_count);
+
+ if (dev->wakeup.prepare_count++)
+ goto out;
+
+ err = acpi_power_on_list(&dev->wakeup.resources);
+ if (err) {
+ dev_err(&dev->dev, "Cannot turn on wakeup power resources\n");
+ dev->wakeup.flags.valid = 0;
+ goto out;
+ }
+
+ /*
+ * Passing 3 as the third argument below means the device may be
+ * put into arbitrary power state afterward.
+ */
+ err = acpi_device_sleep_wake(dev, 1, sleep_state, 3);
+ if (err) {
+ acpi_power_off_list(&dev->wakeup.resources);
+ dev->wakeup.prepare_count = 0;
+ goto out;
+ }
+
+ dev_dbg(&dev->dev, "Wakeup power enabled\n");
+
+ out:
+ mutex_unlock(&acpi_device_lock);
+ return err;
+}
+
+/*
+ * Shutdown a wakeup device, counterpart of above method
+ * 1. Execute _DSW (Device Sleep Wake) or (deprecated in ACPI 3.0) _PSW (Power
+ * State Wake) for the device, if present
+ * 2. Shutdown down the power resources
+ */
+int acpi_disable_wakeup_device_power(struct acpi_device *dev)
+{
+ struct acpi_power_resource_entry *entry;
+ int err = 0;
+
+ if (!dev || !dev->wakeup.flags.valid)
+ return -EINVAL;
+
+ mutex_lock(&acpi_device_lock);
+
+ dev_dbg(&dev->dev, "Disabling wakeup power (count %d)\n",
+ dev->wakeup.prepare_count);
+
+ /* Do nothing if wakeup power has not been enabled for this device. */
+ if (dev->wakeup.prepare_count <= 0)
+ goto out;
+
+ if (--dev->wakeup.prepare_count > 0)
+ goto out;
+
+ err = acpi_device_sleep_wake(dev, 0, 0, 0);
+ if (err)
+ goto out;
+
+ /*
+ * All of the power resources in the list need to be turned off even if
+ * there are errors.
+ */
+ list_for_each_entry(entry, &dev->wakeup.resources, node) {
+ int ret;
+
+ ret = acpi_power_off(entry->resource);
+ if (ret && !err)
+ err = ret;
+ }
+ if (err) {
+ dev_err(&dev->dev, "Cannot turn off wakeup power resources\n");
+ dev->wakeup.flags.valid = 0;
+ goto out;
+ }
+
+ dev_dbg(&dev->dev, "Wakeup power disabled\n");
+
+ out:
+ mutex_unlock(&acpi_device_lock);
+ return err;
+}
+
+int acpi_power_get_inferred_state(struct acpi_device *device, int *state)
+{
+ u8 list_state = ACPI_POWER_RESOURCE_STATE_OFF;
+ int result = 0;
+ int i = 0;
+
+ if (!device || !state)
+ return -EINVAL;
+
+ /*
+ * We know a device's inferred power state when all the resources
+ * required for a given D-state are 'on'.
+ */
+ for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++) {
+ struct list_head *list = &device->power.states[i].resources;
+
+ if (list_empty(list))
+ continue;
+
+ result = acpi_power_get_list_state(list, &list_state);
+ if (result)
+ return result;
+
+ if (list_state == ACPI_POWER_RESOURCE_STATE_ON) {
+ *state = i;
+ return 0;
+ }
+ }
+
+ *state = device->power.states[ACPI_STATE_D3_COLD].flags.valid ?
+ ACPI_STATE_D3_COLD : ACPI_STATE_D3_HOT;
+ return 0;
+}
+
+int acpi_power_on_resources(struct acpi_device *device, int state)
+{
+ if (!device || state < ACPI_STATE_D0 || state > ACPI_STATE_D3_HOT)
+ return -EINVAL;
+
+ return acpi_power_on_list(&device->power.states[state].resources);
+}
+
+int acpi_power_transition(struct acpi_device *device, int state)
+{
+ int result = 0;
+
+ if (!device || (state < ACPI_STATE_D0) || (state > ACPI_STATE_D3_COLD))
+ return -EINVAL;
+
+ if (device->power.state == state || !device->flags.power_manageable)
+ return 0;
+
+ if ((device->power.state < ACPI_STATE_D0)
+ || (device->power.state > ACPI_STATE_D3_COLD))
+ return -ENODEV;
+
+ /*
+ * First we reference all power resources required in the target list
+ * (e.g. so the device doesn't lose power while transitioning). Then,
+ * we dereference all power resources used in the current list.
+ */
+ if (state < ACPI_STATE_D3_COLD)
+ result = acpi_power_on_list(
+ &device->power.states[state].resources);
+
+ if (!result && device->power.state < ACPI_STATE_D3_COLD)
+ acpi_power_off_list(
+ &device->power.states[device->power.state].resources);
+
+ /* We shouldn't change the state unless the above operations succeed. */
+ device->power.state = result ? ACPI_STATE_UNKNOWN : state;
+
+ return result;
+}
+
+static void acpi_release_power_resource(struct device *dev)
+{
+ struct acpi_device *device = to_acpi_device(dev);
+ struct acpi_power_resource *resource;
+
+ resource = container_of(device, struct acpi_power_resource, device);
+
+ mutex_lock(&power_resource_list_lock);
+ list_del(&resource->list_node);
+ mutex_unlock(&power_resource_list_lock);
+
+ acpi_free_pnp_ids(&device->pnp);
+ kfree(resource);
+}
+
+static ssize_t resource_in_use_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct acpi_power_resource *resource;
+
+ resource = to_power_resource(to_acpi_device(dev));
+ return sprintf(buf, "%u\n", !!resource->ref_count);
+}
+static DEVICE_ATTR_RO(resource_in_use);
+
+static void acpi_power_sysfs_remove(struct acpi_device *device)
+{
+ device_remove_file(&device->dev, &dev_attr_resource_in_use);
+}
+
+static void acpi_power_add_resource_to_list(struct acpi_power_resource *resource)
+{
+ mutex_lock(&power_resource_list_lock);
+
+ if (!list_empty(&acpi_power_resource_list)) {
+ struct acpi_power_resource *r;
+
+ list_for_each_entry(r, &acpi_power_resource_list, list_node)
+ if (r->order > resource->order) {
+ list_add_tail(&resource->list_node, &r->list_node);
+ goto out;
+ }
+ }
+ list_add_tail(&resource->list_node, &acpi_power_resource_list);
+
+ out:
+ mutex_unlock(&power_resource_list_lock);
+}
+
+struct acpi_device *acpi_add_power_resource(acpi_handle handle)
+{
+ struct acpi_device *device = acpi_fetch_acpi_dev(handle);
+ struct acpi_power_resource *resource;
+ union acpi_object acpi_object;
+ struct acpi_buffer buffer = { sizeof(acpi_object), &acpi_object };
+ acpi_status status;
+ u8 state_dummy;
+ int result;
+
+ if (device)
+ return device;
+
+ resource = kzalloc(sizeof(*resource), GFP_KERNEL);
+ if (!resource)
+ return NULL;
+
+ device = &resource->device;
+ acpi_init_device_object(device, handle, ACPI_BUS_TYPE_POWER,
+ acpi_release_power_resource);
+ mutex_init(&resource->resource_lock);
+ INIT_LIST_HEAD(&resource->list_node);
+ INIT_LIST_HEAD(&resource->dependents);
+ strcpy(acpi_device_name(device), ACPI_POWER_DEVICE_NAME);
+ strcpy(acpi_device_class(device), ACPI_POWER_CLASS);
+ device->power.state = ACPI_STATE_UNKNOWN;
+ device->flags.match_driver = true;
+
+ /* Evaluate the object to get the system level and resource order. */
+ status = acpi_evaluate_object(handle, NULL, NULL, &buffer);
+ if (ACPI_FAILURE(status))
+ goto err;
+
+ resource->system_level = acpi_object.power_resource.system_level;
+ resource->order = acpi_object.power_resource.resource_order;
+ resource->state = ACPI_POWER_RESOURCE_STATE_UNKNOWN;
+
+ /* Get the initial state or just flip it on if that fails. */
+ if (acpi_power_get_state(resource, &state_dummy))
+ __acpi_power_on(resource);
+
+ acpi_handle_info(handle, "New power resource\n");
+
+ result = acpi_tie_acpi_dev(device);
+ if (result)
+ goto err;
+
+ result = acpi_device_add(device);
+ if (result)
+ goto err;
+
+ if (!device_create_file(&device->dev, &dev_attr_resource_in_use))
+ device->remove = acpi_power_sysfs_remove;
+
+ acpi_power_add_resource_to_list(resource);
+ acpi_device_add_finalize(device);
+ return device;
+
+ err:
+ acpi_release_power_resource(&device->dev);
+ return NULL;
+}
+
+#ifdef CONFIG_ACPI_SLEEP
+void acpi_resume_power_resources(void)
+{
+ struct acpi_power_resource *resource;
+
+ mutex_lock(&power_resource_list_lock);
+
+ list_for_each_entry(resource, &acpi_power_resource_list, list_node) {
+ int result;
+ u8 state;
+
+ mutex_lock(&resource->resource_lock);
+
+ resource->state = ACPI_POWER_RESOURCE_STATE_UNKNOWN;
+ result = acpi_power_get_state(resource, &state);
+ if (result) {
+ mutex_unlock(&resource->resource_lock);
+ continue;
+ }
+
+ if (state == ACPI_POWER_RESOURCE_STATE_OFF
+ && resource->ref_count) {
+ acpi_handle_debug(resource->device.handle, "Turning ON\n");
+ __acpi_power_on(resource);
+ }
+
+ mutex_unlock(&resource->resource_lock);
+ }
+
+ mutex_unlock(&power_resource_list_lock);
+}
+#endif
+
+static const struct dmi_system_id dmi_leave_unused_power_resources_on[] = {
+ {
+ /*
+ * The Toshiba Click Mini has a CPR3 power-resource which must
+ * be on for the touchscreen to work, but which is not in any
+ * _PR? lists. The other 2 affected power-resources are no-ops.
+ */
+ .matches = {
+ DMI_MATCH(DMI_SYS_VENDOR, "TOSHIBA"),
+ DMI_MATCH(DMI_PRODUCT_NAME, "SATELLITE Click Mini L9W-B"),
+ },
+ },
+ {}
+};
+
+/**
+ * acpi_turn_off_unused_power_resources - Turn off power resources not in use.
+ */
+void acpi_turn_off_unused_power_resources(void)
+{
+ struct acpi_power_resource *resource;
+
+ if (dmi_check_system(dmi_leave_unused_power_resources_on))
+ return;
+
+ mutex_lock(&power_resource_list_lock);
+
+ list_for_each_entry_reverse(resource, &acpi_power_resource_list, list_node) {
+ mutex_lock(&resource->resource_lock);
+
+ if (!resource->ref_count &&
+ resource->state == ACPI_POWER_RESOURCE_STATE_ON) {
+ acpi_handle_debug(resource->device.handle, "Turning OFF\n");
+ __acpi_power_off(resource);
+ }
+
+ mutex_unlock(&resource->resource_lock);
+ }
+
+ mutex_unlock(&power_resource_list_lock);
+}