diff options
Diffstat (limited to 'drivers/acpi/power.c')
| -rw-r--r-- | drivers/acpi/power.c | 1066 |
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); +} |