| // 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/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; |
| char *name; |
| u32 system_level; |
| u32 order; |
| unsigned int ref_count; |
| bool wakeup_enabled; |
| 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 |
| 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; |
| |
| if (acpi_bus_get_device(handle, &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]; |
| 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; |
| |
| err = acpi_add_power_resource(rhandle); |
| if (err) |
| break; |
| |
| err = acpi_power_resources_list_add(rhandle, list); |
| if (err) |
| break; |
| } |
| if (err) |
| acpi_power_resources_list_free(list); |
| |
| return err; |
| } |
| |
| static int acpi_power_get_state(acpi_handle handle, int *state) |
| { |
| acpi_status status = AE_OK; |
| unsigned long long sta = 0; |
| |
| if (!handle || !state) |
| return -EINVAL; |
| |
| status = acpi_evaluate_integer(handle, "_STA", NULL, &sta); |
| if (ACPI_FAILURE(status)) |
| return -ENODEV; |
| |
| *state = (sta & 0x01)?ACPI_POWER_RESOURCE_STATE_ON: |
| ACPI_POWER_RESOURCE_STATE_OFF; |
| |
| acpi_handle_debug(handle, "Power resource is %s\n", |
| *state ? "on" : "off"); |
| |
| return 0; |
| } |
| |
| static int acpi_power_get_list_state(struct list_head *list, int *state) |
| { |
| struct acpi_power_resource_entry *entry; |
| int cur_state; |
| |
| if (!list || !state) |
| return -EINVAL; |
| |
| /* The state of the list is 'on' IFF all resources are 'on'. */ |
| cur_state = 0; |
| list_for_each_entry(entry, list, node) { |
| struct acpi_power_resource *resource = entry->resource; |
| acpi_handle handle = resource->device.handle; |
| int result; |
| |
| mutex_lock(&resource->resource_lock); |
| result = acpi_power_get_state(handle, &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->name); |
| |
| 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->name); |
| 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) |
| { |
| struct acpi_power_dependent_device *dep; |
| acpi_status status = AE_OK; |
| |
| status = acpi_evaluate_object(resource->device.handle, "_ON", NULL, NULL); |
| if (ACPI_FAILURE(status)) |
| return -ENODEV; |
| |
| pr_debug("Power resource [%s] turned on\n", resource->name); |
| |
| /* |
| * 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->name); |
| 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++) { |
| pr_debug("Power resource [%s] already on\n", resource->name); |
| } 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_status status; |
| |
| status = acpi_evaluate_object(resource->device.handle, "_OFF", |
| NULL, NULL); |
| if (ACPI_FAILURE(status)) |
| return -ENODEV; |
| |
| pr_debug("Power resource [%s] turned off\n", resource->name); |
| |
| return 0; |
| } |
| |
| static int acpi_power_off_unlocked(struct acpi_power_resource *resource) |
| { |
| int result = 0; |
| |
| if (!resource->ref_count) { |
| pr_debug("Power resource [%s] already off\n", resource->name); |
| return 0; |
| } |
| |
| if (--resource->ref_count) { |
| pr_debug("Power resource [%s] still in use\n", resource->name); |
| } 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; |
| acpi_handle handle = resource->device.handle; |
| int result; |
| int state; |
| |
| mutex_lock(&resource->resource_lock); |
| |
| result = acpi_power_get_state(handle, &state); |
| if (result) { |
| mutex_unlock(&resource->resource_lock); |
| return result; |
| } |
| if (state == ACPI_POWER_RESOURCE_STATE_ON) { |
| resource->ref_count++; |
| resource->wakeup_enabled = true; |
| } |
| 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) |
| { |
| struct acpi_power_resource_entry *entry; |
| int err = 0; |
| |
| if (!dev || !dev->wakeup.flags.valid) |
| return -EINVAL; |
| |
| mutex_lock(&acpi_device_lock); |
| |
| if (dev->wakeup.prepare_count++) |
| goto out; |
| |
| list_for_each_entry(entry, &dev->wakeup.resources, node) { |
| struct acpi_power_resource *resource = entry->resource; |
| |
| mutex_lock(&resource->resource_lock); |
| |
| if (!resource->wakeup_enabled) { |
| err = acpi_power_on_unlocked(resource); |
| if (!err) |
| resource->wakeup_enabled = true; |
| } |
| |
| mutex_unlock(&resource->resource_lock); |
| |
| if (err) { |
| dev_err(&dev->dev, |
| "Cannot turn wakeup power resources on\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) |
| dev->wakeup.prepare_count = 0; |
| |
| 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); |
| |
| if (--dev->wakeup.prepare_count > 0) |
| goto out; |
| |
| /* |
| * Executing the code below even if prepare_count is already zero when |
| * the function is called may be useful, for example for initialisation. |
| */ |
| if (dev->wakeup.prepare_count < 0) |
| dev->wakeup.prepare_count = 0; |
| |
| err = acpi_device_sleep_wake(dev, 0, 0, 0); |
| if (err) |
| goto out; |
| |
| list_for_each_entry(entry, &dev->wakeup.resources, node) { |
| struct acpi_power_resource *resource = entry->resource; |
| |
| mutex_lock(&resource->resource_lock); |
| |
| if (resource->wakeup_enabled) { |
| err = acpi_power_off_unlocked(resource); |
| if (!err) |
| resource->wakeup_enabled = false; |
| } |
| |
| mutex_unlock(&resource->resource_lock); |
| |
| if (err) { |
| dev_err(&dev->dev, |
| "Cannot turn wakeup power resources off\n"); |
| dev->wakeup.flags.valid = 0; |
| break; |
| } |
| } |
| |
| out: |
| mutex_unlock(&acpi_device_lock); |
| return err; |
| } |
| |
| int acpi_power_get_inferred_state(struct acpi_device *device, int *state) |
| { |
| int result = 0; |
| int list_state = 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); |
| } |
| |
| int acpi_add_power_resource(acpi_handle handle) |
| { |
| struct acpi_power_resource *resource; |
| struct acpi_device *device = NULL; |
| union acpi_object acpi_object; |
| struct acpi_buffer buffer = { sizeof(acpi_object), &acpi_object }; |
| acpi_status status; |
| int state, result = -ENODEV; |
| |
| acpi_bus_get_device(handle, &device); |
| if (device) |
| return 0; |
| |
| resource = kzalloc(sizeof(*resource), GFP_KERNEL); |
| if (!resource) |
| return -ENOMEM; |
| |
| device = &resource->device; |
| acpi_init_device_object(device, handle, ACPI_BUS_TYPE_POWER); |
| mutex_init(&resource->resource_lock); |
| INIT_LIST_HEAD(&resource->list_node); |
| INIT_LIST_HEAD(&resource->dependents); |
| resource->name = device->pnp.bus_id; |
| strcpy(acpi_device_name(device), ACPI_POWER_DEVICE_NAME); |
| strcpy(acpi_device_class(device), ACPI_POWER_CLASS); |
| device->power.state = ACPI_STATE_UNKNOWN; |
| |
| /* 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; |
| |
| result = acpi_power_get_state(handle, &state); |
| if (result) |
| goto err; |
| |
| pr_info("%s [%s] (%s)\n", acpi_device_name(device), |
| acpi_device_bid(device), state ? "on" : "off"); |
| |
| device->flags.match_driver = true; |
| result = acpi_device_add(device, acpi_release_power_resource); |
| 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 0; |
| |
| err: |
| acpi_release_power_resource(&device->dev); |
| return result; |
| } |
| |
| #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, state; |
| |
| mutex_lock(&resource->resource_lock); |
| |
| result = acpi_power_get_state(resource->device.handle, &state); |
| if (result) { |
| mutex_unlock(&resource->resource_lock); |
| continue; |
| } |
| |
| if (state == ACPI_POWER_RESOURCE_STATE_OFF |
| && resource->ref_count) { |
| dev_info(&resource->device.dev, "Turning ON\n"); |
| __acpi_power_on(resource); |
| } |
| |
| mutex_unlock(&resource->resource_lock); |
| } |
| |
| mutex_unlock(&power_resource_list_lock); |
| } |
| |
| void acpi_turn_off_unused_power_resources(void) |
| { |
| struct acpi_power_resource *resource; |
| |
| 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) { |
| dev_info(&resource->device.dev, "Turning OFF\n"); |
| __acpi_power_off(resource); |
| } |
| |
| mutex_unlock(&resource->resource_lock); |
| } |
| |
| mutex_unlock(&power_resource_list_lock); |
| } |
| #endif |