diff options
Diffstat (limited to 'drivers/acpi/power.c')
| -rw-r--r-- | drivers/acpi/power.c | 692 |
1 files changed, 692 insertions, 0 deletions
diff --git a/drivers/acpi/power.c b/drivers/acpi/power.c new file mode 100644 index 00000000000..373a3a95bb4 --- /dev/null +++ b/drivers/acpi/power.c @@ -0,0 +1,692 @@ +/* + * 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/proc_fs.h> +#include <linux/seq_file.h> +#include <acpi/acpi_bus.h> +#include <acpi/acpi_drivers.h> + + +#define _COMPONENT ACPI_POWER_COMPONENT +ACPI_MODULE_NAME ("acpi_power") + +#define ACPI_POWER_COMPONENT 0x00800000 +#define ACPI_POWER_CLASS "power_resource" +#define ACPI_POWER_DRIVER_NAME "ACPI Power Resource Driver" +#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_open_fs(struct inode *inode, struct file *file); + +static struct acpi_driver acpi_power_driver = { + .name = ACPI_POWER_DRIVER_NAME, + .class = ACPI_POWER_CLASS, + .ids = ACPI_POWER_HID, + .ops = { + .add = acpi_power_add, + .remove = acpi_power_remove, + }, +}; + +struct acpi_power_resource +{ + acpi_handle handle; + acpi_bus_id name; + u32 system_level; + u32 order; + int state; + int references; +}; + +static struct list_head acpi_power_resource_list; + +static struct file_operations acpi_power_fops = { + .open = acpi_power_open_fs, + .read = seq_read, + .llseek = seq_lseek, + .release = single_release, +}; + +/* -------------------------------------------------------------------------- + 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; + + ACPI_FUNCTION_TRACE("acpi_power_get_context"); + + if (!resource) + return_VALUE(-ENODEV); + + result = acpi_bus_get_device(handle, &device); + if (result) { + ACPI_DEBUG_PRINT((ACPI_DB_WARN, "Error getting context [%p]\n", + handle)); + return_VALUE(result); + } + + *resource = (struct acpi_power_resource *) acpi_driver_data(device); + if (!resource) + return_VALUE(-ENODEV); + + return_VALUE(0); +} + + +static int +acpi_power_get_state ( + struct acpi_power_resource *resource) +{ + acpi_status status = AE_OK; + unsigned long sta = 0; + + ACPI_FUNCTION_TRACE("acpi_power_get_state"); + + if (!resource) + return_VALUE(-EINVAL); + + status = acpi_evaluate_integer(resource->handle, "_STA", NULL, &sta); + if (ACPI_FAILURE(status)) + return_VALUE(-ENODEV); + + if (sta & 0x01) + resource->state = ACPI_POWER_RESOURCE_STATE_ON; + else + resource->state = ACPI_POWER_RESOURCE_STATE_OFF; + + ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Resource [%s] is %s\n", + resource->name, resource->state?"on":"off")); + + return_VALUE(0); +} + + +static int +acpi_power_get_list_state ( + struct acpi_handle_list *list, + int *state) +{ + int result = 0; + struct acpi_power_resource *resource = NULL; + u32 i = 0; + + ACPI_FUNCTION_TRACE("acpi_power_get_list_state"); + + if (!list || !state) + return_VALUE(-EINVAL); + + /* The state of the list is 'on' IFF all resources are 'on'. */ + + for (i=0; i<list->count; i++) { + result = acpi_power_get_context(list->handles[i], &resource); + if (result) + return_VALUE(result); + result = acpi_power_get_state(resource); + if (result) + return_VALUE(result); + + *state = resource->state; + + if (*state != ACPI_POWER_RESOURCE_STATE_ON) + break; + } + + ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Resource list is %s\n", + *state?"on":"off")); + + return_VALUE(result); +} + + +static int +acpi_power_on ( + acpi_handle handle) +{ + int result = 0; + acpi_status status = AE_OK; + struct acpi_device *device = NULL; + struct acpi_power_resource *resource = NULL; + + ACPI_FUNCTION_TRACE("acpi_power_on"); + + result = acpi_power_get_context(handle, &resource); + if (result) + return_VALUE(result); + + resource->references++; + + if ((resource->references > 1) + || (resource->state == ACPI_POWER_RESOURCE_STATE_ON)) { + ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Resource [%s] already on\n", + resource->name)); + return_VALUE(0); + } + + status = acpi_evaluate_object(resource->handle, "_ON", NULL, NULL); + if (ACPI_FAILURE(status)) + return_VALUE(-ENODEV); + + result = acpi_power_get_state(resource); + if (result) + return_VALUE(result); + if (resource->state != ACPI_POWER_RESOURCE_STATE_ON) + return_VALUE(-ENOEXEC); + + /* Update the power resource's _device_ power state */ + result = acpi_bus_get_device(resource->handle, &device); + if (result) + return_VALUE(result); + device->power.state = ACPI_STATE_D0; + + ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Resource [%s] turned on\n", + resource->name)); + + return_VALUE(0); +} + + +static int +acpi_power_off_device ( + acpi_handle handle) +{ + int result = 0; + acpi_status status = AE_OK; + struct acpi_device *device = NULL; + struct acpi_power_resource *resource = NULL; + + ACPI_FUNCTION_TRACE("acpi_power_off_device"); + + result = acpi_power_get_context(handle, &resource); + if (result) + return_VALUE(result); + + if (resource->references) + resource->references--; + + if (resource->references) { + ACPI_DEBUG_PRINT((ACPI_DB_INFO, + "Resource [%s] is still in use, dereferencing\n", + device->pnp.bus_id)); + return_VALUE(0); + } + + if (resource->state == ACPI_POWER_RESOURCE_STATE_OFF) { + ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Resource [%s] already off\n", + device->pnp.bus_id)); + return_VALUE(0); + } + + status = acpi_evaluate_object(resource->handle, "_OFF", NULL, NULL); + if (ACPI_FAILURE(status)) + return_VALUE(-ENODEV); + + result = acpi_power_get_state(resource); + if (result) + return_VALUE(result); + if (resource->state != ACPI_POWER_RESOURCE_STATE_OFF) + return_VALUE(-ENOEXEC); + + /* Update the power resource's _device_ power state */ + result = acpi_bus_get_device(resource->handle, &device); + if (result) + return_VALUE(result); + device->power.state = ACPI_STATE_D3; + + ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Resource [%s] turned off\n", + resource->name)); + + return_VALUE(0); +} + +/* + * Prepare a wakeup device, two steps (Ref ACPI 2.0:P229): + * 1. Power on the power resources required for the wakeup device + * 2. Enable _PSW (power state wake) for the device if present + */ +int acpi_enable_wakeup_device_power (struct acpi_device *dev) +{ + union acpi_object arg = {ACPI_TYPE_INTEGER}; + struct acpi_object_list arg_list = {1, &arg}; + acpi_status status = AE_OK; + int i; + int ret = 0; + + ACPI_FUNCTION_TRACE("acpi_enable_wakeup_device_power"); + if (!dev || !dev->wakeup.flags.valid) + return_VALUE(-1); + + arg.integer.value = 1; + /* Open power resource */ + for (i = 0; i < dev->wakeup.resources.count; i++) { + ret = acpi_power_on(dev->wakeup.resources.handles[i]); + if (ret) { + ACPI_DEBUG_PRINT((ACPI_DB_ERROR, + "Error transition power state\n")); + dev->wakeup.flags.valid = 0; + return_VALUE(-1); + } + } + + /* Execute PSW */ + status = acpi_evaluate_object(dev->handle, "_PSW", &arg_list, NULL); + if (ACPI_FAILURE(status) && (status != AE_NOT_FOUND)) { + ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Error evaluate _PSW\n")); + dev->wakeup.flags.valid = 0; + ret = -1; + } + + return_VALUE(ret); +} + +/* + * Shutdown a wakeup device, counterpart of above method + * 1. Disable _PSW (power state wake) + * 2. Shutdown down the power resources + */ +int acpi_disable_wakeup_device_power (struct acpi_device *dev) +{ + union acpi_object arg = {ACPI_TYPE_INTEGER}; + struct acpi_object_list arg_list = {1, &arg}; + acpi_status status = AE_OK; + int i; + int ret = 0; + + ACPI_FUNCTION_TRACE("acpi_disable_wakeup_device_power"); + + if (!dev || !dev->wakeup.flags.valid) + return_VALUE(-1); + + arg.integer.value = 0; + /* Execute PSW */ + status = acpi_evaluate_object(dev->handle, "_PSW", &arg_list, NULL); + if (ACPI_FAILURE(status) && (status != AE_NOT_FOUND)) { + ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Error evaluate _PSW\n")); + dev->wakeup.flags.valid = 0; + return_VALUE(-1); + } + + /* Close power resource */ + for (i = 0; i < dev->wakeup.resources.count; i++) { + ret = acpi_power_off_device(dev->wakeup.resources.handles[i]); + if (ret) { + ACPI_DEBUG_PRINT((ACPI_DB_ERROR, + "Error transition power state\n")); + dev->wakeup.flags.valid = 0; + return_VALUE(-1); + } + } + + return_VALUE(ret); +} + +/* -------------------------------------------------------------------------- + Device Power Management + -------------------------------------------------------------------------- */ + +int +acpi_power_get_inferred_state ( + struct acpi_device *device) +{ + int result = 0; + struct acpi_handle_list *list = NULL; + int list_state = 0; + int i = 0; + + ACPI_FUNCTION_TRACE("acpi_power_get_inferred_state"); + + if (!device) + return_VALUE(-EINVAL); + + device->power.state = ACPI_STATE_UNKNOWN; + + /* + * 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; i++) { + list = &device->power.states[i].resources; + if (list->count < 1) + continue; + + result = acpi_power_get_list_state(list, &list_state); + if (result) + return_VALUE(result); + + if (list_state == ACPI_POWER_RESOURCE_STATE_ON) { + device->power.state = i; + return_VALUE(0); + } + } + + device->power.state = ACPI_STATE_D3; + + return_VALUE(0); +} + + +int +acpi_power_transition ( + struct acpi_device *device, + int state) +{ + int result = 0; + struct acpi_handle_list *cl = NULL; /* Current Resources */ + struct acpi_handle_list *tl = NULL; /* Target Resources */ + int i = 0; + + ACPI_FUNCTION_TRACE("acpi_power_transition"); + + if (!device || (state < ACPI_STATE_D0) || (state > ACPI_STATE_D3)) + return_VALUE(-EINVAL); + + if ((device->power.state < ACPI_STATE_D0) || (device->power.state > ACPI_STATE_D3)) + return_VALUE(-ENODEV); + + cl = &device->power.states[device->power.state].resources; + tl = &device->power.states[state].resources; + + device->power.state = ACPI_STATE_UNKNOWN; + + if (!cl->count && !tl->count) { + result = -ENODEV; + goto end; + } + + /* 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). + */ + for (i=0; i<tl->count; i++) { + result = acpi_power_on(tl->handles[i]); + if (result) + goto end; + } + + /* + * Then we dereference all power resources used in the current list. + */ + for (i=0; i<cl->count; i++) { + result = acpi_power_off_device(cl->handles[i]); + if (result) + goto end; + } + + /* We shouldn't change the state till all above operations succeed */ + device->power.state = state; +end: + if (result) + ACPI_DEBUG_PRINT((ACPI_DB_WARN, + "Error transitioning device [%s] to D%d\n", + device->pnp.bus_id, state)); + + return_VALUE(result); +} + + +/* -------------------------------------------------------------------------- + FS Interface (/proc) + -------------------------------------------------------------------------- */ + +static struct proc_dir_entry *acpi_power_dir; + +static int acpi_power_seq_show(struct seq_file *seq, void *offset) +{ + struct acpi_power_resource *resource = NULL; + + ACPI_FUNCTION_TRACE("acpi_power_seq_show"); + + resource = (struct acpi_power_resource *)seq->private; + + if (!resource) + goto end; + + seq_puts(seq, "state: "); + switch (resource->state) { + case ACPI_POWER_RESOURCE_STATE_ON: + seq_puts(seq, "on\n"); + break; + case ACPI_POWER_RESOURCE_STATE_OFF: + seq_puts(seq, "off\n"); + break; + default: + seq_puts(seq, "unknown\n"); + break; + } + + seq_printf(seq, "system level: S%d\n" + "order: %d\n" + "reference count: %d\n", + resource->system_level, + resource->order, + resource->references); + +end: + return_VALUE(0); +} + +static int acpi_power_open_fs(struct inode *inode, struct file *file) +{ + return single_open(file, acpi_power_seq_show, PDE(inode)->data); +} + +static int +acpi_power_add_fs ( + struct acpi_device *device) +{ + struct proc_dir_entry *entry = NULL; + + ACPI_FUNCTION_TRACE("acpi_power_add_fs"); + + if (!device) + return_VALUE(-EINVAL); + + if (!acpi_device_dir(device)) { + acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device), + acpi_power_dir); + if (!acpi_device_dir(device)) + return_VALUE(-ENODEV); + } + + /* 'status' [R] */ + entry = create_proc_entry(ACPI_POWER_FILE_STATUS, + S_IRUGO, acpi_device_dir(device)); + if (!entry) + ACPI_DEBUG_PRINT((ACPI_DB_ERROR, + "Unable to create '%s' fs entry\n", + ACPI_POWER_FILE_STATUS)); + else { + entry->proc_fops = &acpi_power_fops; + entry->data = acpi_driver_data(device); + } + + return_VALUE(0); +} + + +static int +acpi_power_remove_fs ( + struct acpi_device *device) +{ + ACPI_FUNCTION_TRACE("acpi_power_remove_fs"); + + if (acpi_device_dir(device)) { + remove_proc_entry(ACPI_POWER_FILE_STATUS, + acpi_device_dir(device)); + remove_proc_entry(acpi_device_bid(device), acpi_power_dir); + acpi_device_dir(device) = NULL; + } + + return_VALUE(0); +} + + +/* -------------------------------------------------------------------------- + Driver Interface + -------------------------------------------------------------------------- */ + +static int +acpi_power_add ( + struct acpi_device *device) +{ + int result = 0; + 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}; + + ACPI_FUNCTION_TRACE("acpi_power_add"); + + if (!device) + return_VALUE(-EINVAL); + + resource = kmalloc(sizeof(struct acpi_power_resource), GFP_KERNEL); + if (!resource) + return_VALUE(-ENOMEM); + memset(resource, 0, sizeof(struct acpi_power_resource)); + + resource->handle = device->handle; + strcpy(resource->name, device->pnp.bus_id); + strcpy(acpi_device_name(device), ACPI_POWER_DEVICE_NAME); + strcpy(acpi_device_class(device), ACPI_POWER_CLASS); + acpi_driver_data(device) = resource; + + /* Evalute the object to get the system level and resource order. */ + status = acpi_evaluate_object(resource->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(resource); + if (result) + goto end; + + switch (resource->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; + } + + result = acpi_power_add_fs(device); + if (result) + goto end; + + printk(KERN_INFO PREFIX "%s [%s] (%s)\n", acpi_device_name(device), + acpi_device_bid(device), resource->state?"on":"off"); + +end: + if (result) + kfree(resource); + + return_VALUE(result); +} + + +static int +acpi_power_remove ( + struct acpi_device *device, + int type) +{ + struct acpi_power_resource *resource = NULL; + + ACPI_FUNCTION_TRACE("acpi_power_remove"); + + if (!device || !acpi_driver_data(device)) + return_VALUE(-EINVAL); + + resource = (struct acpi_power_resource *) acpi_driver_data(device); + + acpi_power_remove_fs(device); + + kfree(resource); + + return_VALUE(0); +} + + +static int __init acpi_power_init (void) +{ + int result = 0; + + ACPI_FUNCTION_TRACE("acpi_power_init"); + + if (acpi_disabled) + return_VALUE(0); + + INIT_LIST_HEAD(&acpi_power_resource_list); + + acpi_power_dir = proc_mkdir(ACPI_POWER_CLASS, acpi_root_dir); + if (!acpi_power_dir) + return_VALUE(-ENODEV); + + result = acpi_bus_register_driver(&acpi_power_driver); + if (result < 0) { + remove_proc_entry(ACPI_POWER_CLASS, acpi_root_dir); + return_VALUE(-ENODEV); + } + + return_VALUE(0); +} + +subsys_initcall(acpi_power_init); + |