diff options
Diffstat (limited to 'drivers/acpi/power.c')
| -rw-r--r-- | drivers/acpi/power.c | 805 |
1 files changed, 805 insertions, 0 deletions
diff --git a/drivers/acpi/power.c b/drivers/acpi/power.c new file mode 100644 index 00000000..0500f719 --- /dev/null +++ b/drivers/acpi/power.c @@ -0,0 +1,805 @@ +/* + * acpi_power.c - ACPI Bus Power Management ($Revision: 39 $) + * + * Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com> + * Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com> + * + * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or (at + * your option) any later version. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public License along + * with this program; if not, write to the Free Software Foundation, Inc., + * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. + * + * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + */ + +/* + * ACPI power-managed devices may be controlled in two ways: + * 1. via "Device Specific (D-State) Control" + * 2. via "Power Resource Control". + * This module is used to manage devices relying on Power Resource Control. + * + * An ACPI "power resource object" describes a software controllable power + * plane, clock plane, or other resource used by a power managed device. + * A device may rely on multiple power resources, and a power resource + * may be shared by multiple devices. + */ + +#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 <acpi/acpi_bus.h> +#include <acpi/acpi_drivers.h> +#include "sleep.h" +#include "internal.h" + +#define PREFIX "ACPI: " + +#define _COMPONENT ACPI_POWER_COMPONENT +ACPI_MODULE_NAME("power"); +#define ACPI_POWER_CLASS "power_resource" +#define ACPI_POWER_DEVICE_NAME "Power Resource" +#define ACPI_POWER_FILE_INFO "info" +#define ACPI_POWER_FILE_STATUS "state" +#define ACPI_POWER_RESOURCE_STATE_OFF 0x00 +#define ACPI_POWER_RESOURCE_STATE_ON 0x01 +#define ACPI_POWER_RESOURCE_STATE_UNKNOWN 0xFF + +static int acpi_power_add(struct acpi_device *device); +static int acpi_power_remove(struct acpi_device *device, int type); +static int acpi_power_resume(struct acpi_device *device); + +static const struct acpi_device_id power_device_ids[] = { + {ACPI_POWER_HID, 0}, + {"", 0}, +}; +MODULE_DEVICE_TABLE(acpi, power_device_ids); + +static struct acpi_driver acpi_power_driver = { + .name = "power", + .class = ACPI_POWER_CLASS, + .ids = power_device_ids, + .ops = { + .add = acpi_power_add, + .remove = acpi_power_remove, + .resume = acpi_power_resume, + }, +}; + +/* + * A power managed device + * A device may rely on multiple power resources. + * */ +struct acpi_power_managed_device { + struct device *dev; /* The physical device */ + acpi_handle *handle; +}; + +struct acpi_power_resource_device { + struct acpi_power_managed_device *device; + struct acpi_power_resource_device *next; +}; + +struct acpi_power_resource { + struct acpi_device * device; + acpi_bus_id name; + u32 system_level; + u32 order; + unsigned int ref_count; + struct mutex resource_lock; + + /* List of devices relying on this power resource */ + struct acpi_power_resource_device *devices; +}; + +static struct list_head acpi_power_resource_list; + +/* -------------------------------------------------------------------------- + Power Resource Management + -------------------------------------------------------------------------- */ + +static int +acpi_power_get_context(acpi_handle handle, + struct acpi_power_resource **resource) +{ + int result = 0; + struct acpi_device *device = NULL; + + + if (!resource) + return -ENODEV; + + result = acpi_bus_get_device(handle, &device); + if (result) { + printk(KERN_WARNING PREFIX "Getting context [%p]\n", handle); + return result; + } + + *resource = acpi_driver_data(device); + if (!*resource) + return -ENODEV; + + return 0; +} + +static int acpi_power_get_state(acpi_handle handle, int *state) +{ + acpi_status status = AE_OK; + unsigned long long sta = 0; + char node_name[5]; + struct acpi_buffer buffer = { sizeof(node_name), node_name }; + + + 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_get_name(handle, ACPI_SINGLE_NAME, &buffer); + + ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Resource [%s] is %s\n", + node_name, + *state ? "on" : "off")); + + return 0; +} + +static int acpi_power_get_list_state(struct acpi_handle_list *list, int *state) +{ + int cur_state; + int i = 0; + + if (!list || !state) + return -EINVAL; + + /* The state of the list is 'on' IFF all resources are 'on'. */ + + for (i = 0; i < list->count; i++) { + struct acpi_power_resource *resource; + acpi_handle handle = list->handles[i]; + int result; + + result = acpi_power_get_context(handle, &resource); + if (result) + return 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; + } + + ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Resource list is %s\n", + cur_state ? "on" : "off")); + + *state = cur_state; + + return 0; +} + +/* Resume the device when all power resources in _PR0 are on */ +static void acpi_power_on_device(struct acpi_power_managed_device *device) +{ + struct acpi_device *acpi_dev; + acpi_handle handle = device->handle; + int state; + + if (acpi_bus_get_device(handle, &acpi_dev)) + return; + + if(acpi_power_get_inferred_state(acpi_dev, &state)) + return; + + if (state == ACPI_STATE_D0 && pm_runtime_suspended(device->dev)) + pm_request_resume(device->dev); +} + +static int __acpi_power_on(struct acpi_power_resource *resource) +{ + struct acpi_power_resource_device *device_list = resource->devices; + acpi_status status = AE_OK; + + status = acpi_evaluate_object(resource->device->handle, "_ON", NULL, NULL); + if (ACPI_FAILURE(status)) + return -ENODEV; + + /* Update the power resource's _device_ power state */ + resource->device->power.state = ACPI_STATE_D0; + + ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Power resource [%s] turned on\n", + resource->name)); + + while (device_list) { + acpi_power_on_device(device_list->device); + + device_list = device_list->next; + } + + return 0; +} + +static int acpi_power_on(acpi_handle handle) +{ + int result = 0; + struct acpi_power_resource *resource = NULL; + + result = acpi_power_get_context(handle, &resource); + if (result) + return result; + + mutex_lock(&resource->resource_lock); + + if (resource->ref_count++) { + ACPI_DEBUG_PRINT((ACPI_DB_INFO, + "Power resource [%s] already on", + resource->name)); + } else { + result = __acpi_power_on(resource); + if (result) + resource->ref_count--; + } + + mutex_unlock(&resource->resource_lock); + + return result; +} + +static int acpi_power_off(acpi_handle handle) +{ + int result = 0; + acpi_status status = AE_OK; + struct acpi_power_resource *resource = NULL; + + result = acpi_power_get_context(handle, &resource); + if (result) + return result; + + mutex_lock(&resource->resource_lock); + + if (!resource->ref_count) { + ACPI_DEBUG_PRINT((ACPI_DB_INFO, + "Power resource [%s] already off", + resource->name)); + goto unlock; + } + + if (--resource->ref_count) { + ACPI_DEBUG_PRINT((ACPI_DB_INFO, + "Power resource [%s] still in use\n", + resource->name)); + goto unlock; + } + + status = acpi_evaluate_object(resource->device->handle, "_OFF", NULL, NULL); + if (ACPI_FAILURE(status)) { + result = -ENODEV; + } else { + /* Update the power resource's _device_ power state */ + resource->device->power.state = ACPI_STATE_D3; + + ACPI_DEBUG_PRINT((ACPI_DB_INFO, + "Power resource [%s] turned off\n", + resource->name)); + } + + unlock: + mutex_unlock(&resource->resource_lock); + + return result; +} + +static void __acpi_power_off_list(struct acpi_handle_list *list, int num_res) +{ + int i; + + for (i = num_res - 1; i >= 0 ; i--) + acpi_power_off(list->handles[i]); +} + +static void acpi_power_off_list(struct acpi_handle_list *list) +{ + __acpi_power_off_list(list, list->count); +} + +static int acpi_power_on_list(struct acpi_handle_list *list) +{ + int result = 0; + int i; + + for (i = 0; i < list->count; i++) { + result = acpi_power_on(list->handles[i]); + if (result) { + __acpi_power_off_list(list, i); + break; + } + } + + return result; +} + +static void __acpi_power_resource_unregister_device(struct device *dev, + acpi_handle res_handle) +{ + struct acpi_power_resource *resource = NULL; + struct acpi_power_resource_device *prev, *curr; + + if (acpi_power_get_context(res_handle, &resource)) + return; + + mutex_lock(&resource->resource_lock); + prev = NULL; + curr = resource->devices; + while (curr) { + if (curr->device->dev == dev) { + if (!prev) + resource->devices = curr->next; + else + prev->next = curr->next; + + kfree(curr); + break; + } + + prev = curr; + curr = curr->next; + } + mutex_unlock(&resource->resource_lock); +} + +/* Unlink dev from all power resources in _PR0 */ +void acpi_power_resource_unregister_device(struct device *dev, acpi_handle handle) +{ + struct acpi_device *acpi_dev; + struct acpi_handle_list *list; + int i; + + if (!dev || !handle) + return; + + if (acpi_bus_get_device(handle, &acpi_dev)) + return; + + list = &acpi_dev->power.states[ACPI_STATE_D0].resources; + + for (i = 0; i < list->count; i++) + __acpi_power_resource_unregister_device(dev, + list->handles[i]); +} + +static int __acpi_power_resource_register_device( + struct acpi_power_managed_device *powered_device, acpi_handle handle) +{ + struct acpi_power_resource *resource = NULL; + struct acpi_power_resource_device *power_resource_device; + int result; + + result = acpi_power_get_context(handle, &resource); + if (result) + return result; + + power_resource_device = kzalloc( + sizeof(*power_resource_device), GFP_KERNEL); + if (!power_resource_device) + return -ENOMEM; + + power_resource_device->device = powered_device; + + mutex_lock(&resource->resource_lock); + power_resource_device->next = resource->devices; + resource->devices = power_resource_device; + mutex_unlock(&resource->resource_lock); + + return 0; +} + +/* Link dev to all power resources in _PR0 */ +int acpi_power_resource_register_device(struct device *dev, acpi_handle handle) +{ + struct acpi_device *acpi_dev; + struct acpi_handle_list *list; + struct acpi_power_managed_device *powered_device; + int i, ret; + + if (!dev || !handle) + return -ENODEV; + + ret = acpi_bus_get_device(handle, &acpi_dev); + if (ret) + goto no_power_resource; + + if (!acpi_dev->power.flags.power_resources) + goto no_power_resource; + + powered_device = kzalloc(sizeof(*powered_device), GFP_KERNEL); + if (!powered_device) + return -ENOMEM; + + powered_device->dev = dev; + powered_device->handle = handle; + + list = &acpi_dev->power.states[ACPI_STATE_D0].resources; + + for (i = 0; i < list->count; i++) { + ret = __acpi_power_resource_register_device(powered_device, + list->handles[i]); + + if (ret) { + acpi_power_resource_unregister_device(dev, handle); + break; + } + } + + return ret; + +no_power_resource: + printk(KERN_WARNING PREFIX "Invalid Power Resource to register!"); + return -ENODEV; +} + +/** + * 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 agruments 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 agruments + * 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) { + printk(KERN_ERR PREFIX "_DSW execution failed\n"); + dev->wakeup.flags.valid = 0; + return -ENODEV; + } + + /* Execute _PSW */ + arg_list.count = 1; + in_arg[0].integer.value = enable; + status = acpi_evaluate_object(dev->handle, "_PSW", &arg_list, NULL); + if (ACPI_FAILURE(status) && (status != AE_NOT_FOUND)) { + printk(KERN_ERR PREFIX "_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 i, err = 0; + + if (!dev || !dev->wakeup.flags.valid) + return -EINVAL; + + mutex_lock(&acpi_device_lock); + + if (dev->wakeup.prepare_count++) + goto out; + + /* Open power resource */ + for (i = 0; i < dev->wakeup.resources.count; i++) { + int ret = acpi_power_on(dev->wakeup.resources.handles[i]); + if (ret) { + printk(KERN_ERR PREFIX "Transition power state\n"); + dev->wakeup.flags.valid = 0; + err = -ENODEV; + goto err_out; + } + } + + /* + * Passing 3 as the third argument below means the device may be placed + * in arbitrary power state afterwards. + */ + err = acpi_device_sleep_wake(dev, 1, sleep_state, 3); + + err_out: + 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) +{ + int i, 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; + + /* Close power resource */ + for (i = 0; i < dev->wakeup.resources.count; i++) { + int ret = acpi_power_off(dev->wakeup.resources.handles[i]); + if (ret) { + printk(KERN_ERR PREFIX "Transition power state\n"); + dev->wakeup.flags.valid = 0; + err = -ENODEV; + goto out; + } + } + + out: + mutex_unlock(&acpi_device_lock); + return err; +} + +/* -------------------------------------------------------------------------- + Device Power Management + -------------------------------------------------------------------------- */ + +int acpi_power_get_inferred_state(struct acpi_device *device, int *state) +{ + int result = 0; + struct acpi_handle_list *list = NULL; + 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++) { + list = &device->power.states[i].resources; + if (list->count < 1) + 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 = ACPI_STATE_D3; + return 0; +} + +int acpi_power_on_resources(struct acpi_device *device, int state) +{ + if (!device || state < ACPI_STATE_D0 || state > ACPI_STATE_D3) + 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) + return 0; + + if ((device->power.state < ACPI_STATE_D0) + || (device->power.state > ACPI_STATE_D3_COLD)) + return -ENODEV; + + /* TBD: Resources must be ordered. */ + + /* + * 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; +} + +/* -------------------------------------------------------------------------- + Driver Interface + -------------------------------------------------------------------------- */ + +static int acpi_power_add(struct acpi_device *device) +{ + int result = 0, state; + acpi_status status = AE_OK; + struct acpi_power_resource *resource = NULL; + union acpi_object acpi_object; + struct acpi_buffer buffer = { sizeof(acpi_object), &acpi_object }; + + + if (!device) + return -EINVAL; + + resource = kzalloc(sizeof(struct acpi_power_resource), GFP_KERNEL); + if (!resource) + return -ENOMEM; + + resource->device = device; + mutex_init(&resource->resource_lock); + strcpy(resource->name, device->pnp.bus_id); + strcpy(acpi_device_name(device), ACPI_POWER_DEVICE_NAME); + strcpy(acpi_device_class(device), ACPI_POWER_CLASS); + device->driver_data = resource; + + /* Evalute the object to get the system level and resource order. */ + status = acpi_evaluate_object(device->handle, NULL, NULL, &buffer); + if (ACPI_FAILURE(status)) { + result = -ENODEV; + goto end; + } + resource->system_level = acpi_object.power_resource.system_level; + resource->order = acpi_object.power_resource.resource_order; + + result = acpi_power_get_state(device->handle, &state); + if (result) + goto end; + + switch (state) { + case ACPI_POWER_RESOURCE_STATE_ON: + device->power.state = ACPI_STATE_D0; + break; + case ACPI_POWER_RESOURCE_STATE_OFF: + device->power.state = ACPI_STATE_D3; + break; + default: + device->power.state = ACPI_STATE_UNKNOWN; + break; + } + + printk(KERN_INFO PREFIX "%s [%s] (%s)\n", acpi_device_name(device), + acpi_device_bid(device), state ? "on" : "off"); + + end: + if (result) + kfree(resource); + + return result; +} + +static int acpi_power_remove(struct acpi_device *device, int type) +{ + struct acpi_power_resource *resource; + + if (!device) + return -EINVAL; + + resource = acpi_driver_data(device); + if (!resource) + return -EINVAL; + + kfree(resource); + + return 0; +} + +static int acpi_power_resume(struct acpi_device *device) +{ + int result = 0, state; + struct acpi_power_resource *resource; + + if (!device) + return -EINVAL; + + resource = acpi_driver_data(device); + if (!resource) + return -EINVAL; + + mutex_lock(&resource->resource_lock); + + result = acpi_power_get_state(device->handle, &state); + if (result) + goto unlock; + + if (state == ACPI_POWER_RESOURCE_STATE_OFF && resource->ref_count) + result = __acpi_power_on(resource); + + unlock: + mutex_unlock(&resource->resource_lock); + + return result; +} + +int __init acpi_power_init(void) +{ + INIT_LIST_HEAD(&acpi_power_resource_list); + return acpi_bus_register_driver(&acpi_power_driver); +} |