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/* * 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("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 int acpi_power_nocheck; module_param_named(power_nocheck, acpi_power_nocheck, bool, 000); 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 int acpi_power_open_fs(struct inode *inode, struct file *file); static 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, }, }; struct acpi_power_reference { struct list_head node; struct acpi_device *device; }; struct acpi_power_resource { struct acpi_device * device; acpi_bus_id name; u32 system_level; u32 order; struct mutex resource_lock; struct list_head reference; }; static struct list_head acpi_power_resource_list; static const struct file_operations acpi_power_fops = { .owner = THIS_MODULE, .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 = 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 result = 0, state1; 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++) { /* * The state of the power resource can be obtained by * using the ACPI handle. In such case it is unnecessary to * get the Power resource first and then get its state again. */ result = acpi_power_get_state(list->handles[i], &state1); if (result) return result; *state = state1; 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, struct acpi_device *dev) { int result = 0; int found = 0; acpi_status status = AE_OK; struct acpi_power_resource *resource = NULL; struct list_head *node, *next; struct acpi_power_reference *ref; result = acpi_power_get_context(handle, &resource); if (result) return result; mutex_lock(&resource->resource_lock); list_for_each_safe(node, next, &resource->reference) { ref = container_of(node, struct acpi_power_reference, node); if (dev->handle == ref->device->handle) { ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] already referenced by resource [%s]\n", dev->pnp.bus_id, resource->name)); found = 1; break; } } if (!found) { ref = kmalloc(sizeof (struct acpi_power_reference), irqs_disabled() ? GFP_ATOMIC : GFP_KERNEL); if (!ref) { ACPI_DEBUG_PRINT((ACPI_DB_INFO, "kmalloc() failed\n")); mutex_unlock(&resource->resource_lock); return -ENOMEM; } list_add_tail(&ref->node, &resource->reference); ref->device = dev; ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] added to resource [%s] references\n", dev->pnp.bus_id, resource->name)); } mutex_unlock(&resource->resource_lock); 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, "Resource [%s] turned on\n", resource->name)); return 0; } static int acpi_power_off_device(acpi_handle handle, struct acpi_device *dev) { int result = 0; acpi_status status = AE_OK; struct acpi_power_resource *resource = NULL; struct list_head *node, *next; struct acpi_power_reference *ref; result = acpi_power_get_context(handle, &resource); if (result) return result; mutex_lock(&resource->resource_lock); list_for_each_safe(node, next, &resource->reference) { ref = container_of(node, struct acpi_power_reference, node); if (dev->handle == ref->device->handle) { list_del(&ref->node); kfree(ref); ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] removed from resource [%s] references\n", dev->pnp.bus_id, resource->name)); break; } } if (!list_empty(&resource->reference)) { ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Cannot turn resource [%s] off - resource is in use\n", resource->name)); mutex_unlock(&resource->resource_lock); return 0; } mutex_unlock(&resource->resource_lock); status = acpi_evaluate_object(resource->device->handle, "_OFF", NULL, NULL); if (ACPI_FAILURE(status)) return -ENODEV; /* 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; } /** * 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; if (!dev || !dev->wakeup.flags.valid) return -EINVAL; /* * Do not execute the code below twice in a row without calling * acpi_disable_wakeup_device_power() in between for the same device */ if (dev->wakeup.flags.prepared) return 0; /* Open power resource */ for (i = 0; i < dev->wakeup.resources.count; i++) { int ret = acpi_power_on(dev->wakeup.resources.handles[i], dev); if (ret) { printk(KERN_ERR PREFIX "Transition power state\n"); dev->wakeup.flags.valid = 0; return -ENODEV; } } /* * 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); if (!err) dev->wakeup.flags.prepared = 1; 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, ret; if (!dev || !dev->wakeup.flags.valid) return -EINVAL; /* * Do not execute the code below twice in a row without calling * acpi_enable_wakeup_device_power() in between for the same device */ if (!dev->wakeup.flags.prepared) return 0; dev->wakeup.flags.prepared = 0; ret = acpi_device_sleep_wake(dev, 0, 0, 0); if (ret) return ret; /* Close power resource */ for (i = 0; i < dev->wakeup.resources.count; i++) { ret = acpi_power_off_device(dev->wakeup.resources.handles[i], dev); if (ret) { printk(KERN_ERR PREFIX "Transition power state\n"); dev->wakeup.flags.valid = 0; return -ENODEV; } } 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; /* 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], device); if (result) goto end; } if (device->power.state == state) { 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], device); if (result) goto end; } end: if (result) device->power.state = ACPI_STATE_UNKNOWN; else { /* We shouldn't change the state till all above operations succeed */ device->power.state = 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) { int count = 0; int result = 0, state; struct acpi_power_resource *resource = NULL; struct list_head *node, *next; struct acpi_power_reference *ref; resource = seq->private; if (!resource) goto end; result = acpi_power_get_state(resource->device->handle, &state); if (result) goto end; seq_puts(seq, "state: "); switch (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; } mutex_lock(&resource->resource_lock); list_for_each_safe(node, next, &resource->reference) { ref = container_of(node, struct acpi_power_reference, node); count++; } mutex_unlock(&resource->resource_lock); seq_printf(seq, "system level: S%d\n" "order: %d\n" "reference count: %d\n", resource->system_level, resource->order, count); 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 = proc_create_data(ACPI_POWER_FILE_STATUS, S_IRUGO, acpi_device_dir(device), &acpi_power_fops, acpi_driver_data(device)); if (!entry) return -EIO; 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, 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); INIT_LIST_HEAD(&resource->reference); 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; } 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), 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; struct list_head *node, *next; if (!device || !acpi_driver_data(device)) return -EINVAL; resource = acpi_driver_data(device); acpi_power_remove_fs(device); mutex_lock(&resource->resource_lock); list_for_each_safe(node, next, &resource->reference) { struct acpi_power_reference *ref = container_of(node, struct acpi_power_reference, node); list_del(&ref->node); kfree(ref); } mutex_unlock(&resource->resource_lock); kfree(resource); return 0; } static int acpi_power_resume(struct acpi_device *device) { int result = 0, state; struct acpi_power_resource *resource = NULL; struct acpi_power_reference *ref; if (!device || !acpi_driver_data(device)) return -EINVAL; resource = acpi_driver_data(device); result = acpi_power_get_state(device->handle, &state); if (result) return result; mutex_lock(&resource->resource_lock); if (state == ACPI_POWER_RESOURCE_STATE_OFF && !list_empty(&resource->reference)) { ref = container_of(resource->reference.next, struct acpi_power_reference, node); mutex_unlock(&resource->resource_lock); result = acpi_power_on(device->handle, ref->device); return result; } mutex_unlock(&resource->resource_lock); return 0; } int __init acpi_power_init(void) { int result = 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; } |
