/* * 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 { struct acpi_device * device; acpi_bus_id name; u32 system_level; u32 order; int state; int references; }; static struct list_head acpi_power_resource_list; static const 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; 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 = (struct acpi_power_resource *)acpi_driver_data(device); if (!resource) return -ENODEV; return 0; } static int acpi_power_get_state(struct acpi_power_resource *resource) { acpi_status status = AE_OK; unsigned long sta = 0; if (!resource) return -EINVAL; status = acpi_evaluate_integer(resource->device->handle, "_STA", NULL, &sta); if (ACPI_FAILURE(status)) return -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 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; if (!list || !state) return -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 result; result = acpi_power_get_state(resource); if (result) return 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 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; result = acpi_power_get_context(handle, &resource); if (result) return 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 0; } status = acpi_evaluate_object(resource->device->handle, "_ON", NULL, NULL); if (ACPI_FAILURE(status)) return -ENODEV; result = acpi_power_get_state(resource); if (result) return result; if (resource->state != ACPI_POWER_RESOURCE_STATE_ON) return -ENOEXEC; /* Update the power resource's _device_ power state */ device = resource->device; resource->device->power.state = ACPI_STATE_D0; ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Resource [%s] turned on\n", resource->name)); return 0; } static int acpi_power_off_device(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; if (resource->references) resource->references--; if (resource->references) { ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Resource [%s] is still in use, dereferencing\n", resource->device->pnp.bus_id)); return 0; } if (resource->state == ACPI_POWER_RESOURCE_STATE_OFF) { ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Resource [%s] already off\n", resource->device->pnp.bus_id)); return 0; } status = acpi_evaluate_object(resource->device->handle, "_OFF", NULL, NULL); if (ACPI_FAILURE(status)) return -ENODEV; result = acpi_power_get_state(resource); if (result) return result; if (resource->state != ACPI_POWER_RESOURCE_STATE_OFF) return -ENOEXEC; /* Update the power resource's _device_ power state */ resource->device->power.state = ACPI_STATE_D3; ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Resource [%s] turned off\n", resource->name)); 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. 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; if (!dev || !dev->wakeup.flags.valid) return -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) { printk(KERN_ERR PREFIX "Transition power state\n"); dev->wakeup.flags.valid = 0; return -1; } } /* Execute PSW */ status = acpi_evaluate_object(dev->handle, "_PSW", &arg_list, NULL); if (ACPI_FAILURE(status) && (status != AE_NOT_FOUND)) { printk(KERN_ERR PREFIX "Evaluate _PSW\n"); dev->wakeup.flags.valid = 0; ret = -1; } return 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; if (!dev || !dev->wakeup.flags.valid) return -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)) { printk(KERN_ERR PREFIX "Evaluate _PSW\n"); dev->wakeup.flags.valid = 0; return -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) { printk(KERN_ERR PREFIX "Transition power state\n"); dev->wakeup.flags.valid = 0; return -1; } } return 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; if (!device) return -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 result; if (list_state == ACPI_POWER_RESOURCE_STATE_ON) { device->power.state = i; return 0; } } device->power.state = ACPI_STATE_D3; return 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; if (!device || (state < ACPI_STATE_D0) || (state > ACPI_STATE_D3)) return -EINVAL; if ((device->power.state < ACPI_STATE_D0) || (device->power.state > ACPI_STATE_D3)) return -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) printk(KERN_WARNING PREFIX "Transitioning device [%s] to D%d\n", device->pnp.bus_id, state); return 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; 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 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; if (!device) return -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 -ENODEV; } /* 'status' [R] */ entry = create_proc_entry(ACPI_POWER_FILE_STATUS, S_IRUGO, acpi_device_dir(device)); if (!entry) return -EIO; else { entry->proc_fops = &acpi_power_fops; entry->data = acpi_driver_data(device); } return 0; } static int acpi_power_remove_fs(struct acpi_device *device) { 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 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 }; if (!device) return -EINVAL; resource = kmalloc(sizeof(struct acpi_power_resource), GFP_KERNEL); if (!resource) return -ENOMEM; memset(resource, 0, sizeof(struct acpi_power_resource)); resource->device = device; 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(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(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 result; } static int acpi_power_remove(struct acpi_device *device, int type) { struct acpi_power_resource *resource = NULL; if (!device || !acpi_driver_data(device)) return -EINVAL; resource = (struct acpi_power_resource *)acpi_driver_data(device); acpi_power_remove_fs(device); kfree(resource); return 0; } static int __init acpi_power_init(void) { int result = 0; if (acpi_disabled) return 0; INIT_LIST_HEAD(&acpi_power_resource_list); acpi_power_dir = proc_mkdir(ACPI_POWER_CLASS, acpi_root_dir); if (!acpi_power_dir) return -ENODEV; result = acpi_bus_register_driver(&acpi_power_driver); if (result < 0) { remove_proc_entry(ACPI_POWER_CLASS, acpi_root_dir); return -ENODEV; } return 0; } subsys_initcall(acpi_power_init);