ACPI / PM: Rework the handling of devices depending on power resources
Commit 0090def6 (ACPI: Add interface to register/unregister device
to/from power resources) made it possible to indicate to the ACPI
core that if the given device depends on any power resources, then
it should be resumed as soon as all of the power resources required
by it to transition to the D0 power state have been turned on.
Unfortunately, however, this was a mistake, because all devices
depending on power resources should be treated this way (i.e. they
should be resumed when all power resources required by their D0
state have been turned on) and for the majority of those devices
the ACPI core can figure out by itself which (physical) devices
depend on what power resources.
For this reason, replace the code added by commit 0090def6 with a
new, much more straightforward, mechanism that will be used
internally by the ACPI core and remove all references to that code
from kernel subsystems using ACPI.
For the cases when there are (physical) devices that should be
resumed whenever a not directly related ACPI device node goes into
D0 as a result of power resources configuration changes, like in
the SATA case, add two new routines, acpi_dev_pm_add_dependent()
and acpi_dev_pm_remove_dependent(), allowing subsystems to manage
such dependencies. Convert the SATA subsystem to use the new
functions accordingly.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
diff --git a/drivers/acpi/power.c b/drivers/acpi/power.c
index 6e7b9d5..659386c 100644
--- a/drivers/acpi/power.c
+++ b/drivers/acpi/power.c
@@ -83,31 +83,20 @@
.drv.pm = &acpi_power_pm,
};
-/*
- * 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_dependent_device {
+ struct list_head node;
+ struct acpi_device *adev;
+ struct work_struct work;
};
struct acpi_power_resource {
- struct acpi_device * device;
+ struct acpi_device *device;
+ struct list_head dependent;
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;
- struct mutex devices_lock;
};
static struct list_head acpi_power_resource_list;
@@ -207,21 +196,30 @@
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)
+static void acpi_power_resume_dependent(struct work_struct *work)
{
- struct acpi_device *acpi_dev;
- acpi_handle handle = device->handle;
+ struct acpi_power_dependent_device *dep;
+ struct acpi_device_physical_node *pn;
+ struct acpi_device *adev;
int state;
- if (acpi_bus_get_device(handle, &acpi_dev))
+ dep = container_of(work, struct acpi_power_dependent_device, work);
+ adev = dep->adev;
+ if (acpi_power_get_inferred_state(adev, &state))
return;
- if(acpi_power_get_inferred_state(acpi_dev, &state))
+ if (state > ACPI_STATE_D0)
return;
- if (state == ACPI_STATE_D0 && pm_runtime_suspended(device->dev))
- pm_request_resume(device->dev);
+ mutex_lock(&adev->physical_node_lock);
+
+ list_for_each_entry(pn, &adev->physical_node_list, node)
+ pm_request_resume(pn->dev);
+
+ list_for_each_entry(pn, &adev->power_dependent, node)
+ pm_request_resume(pn->dev);
+
+ mutex_unlock(&adev->physical_node_lock);
}
static int __acpi_power_on(struct acpi_power_resource *resource)
@@ -244,9 +242,7 @@
static int acpi_power_on(acpi_handle handle)
{
int result = 0;
- bool resume_device = false;
struct acpi_power_resource *resource = NULL;
- struct acpi_power_resource_device *device_list;
result = acpi_power_get_context(handle, &resource);
if (result)
@@ -260,27 +256,18 @@
resource->name));
} else {
result = __acpi_power_on(resource);
- if (result)
+ if (result) {
resource->ref_count--;
- else
- resume_device = true;
+ } else {
+ struct acpi_power_dependent_device *dep;
+
+ list_for_each_entry(dep, &resource->dependent, node)
+ schedule_work(&dep->work);
+ }
}
mutex_unlock(&resource->resource_lock);
- if (!resume_device)
- return result;
-
- mutex_lock(&resource->devices_lock);
-
- device_list = resource->devices;
- while (device_list) {
- acpi_power_on_device(device_list->device);
- device_list = device_list->next;
- }
-
- mutex_unlock(&resource->devices_lock);
-
return result;
}
@@ -357,119 +344,81 @@
return result;
}
-static void __acpi_power_resource_unregister_device(struct device *dev,
- acpi_handle res_handle)
+static void acpi_power_add_dependent(acpi_handle rhandle,
+ struct acpi_device *adev)
{
- struct acpi_power_resource *resource = NULL;
- struct acpi_power_resource_device *prev, *curr;
+ struct acpi_power_dependent_device *dep;
+ struct acpi_power_resource *resource;
- if (acpi_power_get_context(res_handle, &resource))
+ if (!rhandle || !adev || acpi_power_get_context(rhandle, &resource))
return;
- mutex_lock(&resource->devices_lock);
- prev = NULL;
- curr = resource->devices;
- while (curr) {
- if (curr->device->dev == dev) {
- if (!prev)
- resource->devices = curr->next;
+ mutex_lock(&resource->resource_lock);
+
+ list_for_each_entry(dep, &resource->dependent, node)
+ if (dep->adev == adev)
+ goto out;
+
+ dep = kzalloc(sizeof(*dep), GFP_KERNEL);
+ if (!dep)
+ goto out;
+
+ dep->adev = adev;
+ INIT_WORK(&dep->work, acpi_power_resume_dependent);
+ list_add_tail(&dep->node, &resource->dependent);
+
+ out:
+ mutex_unlock(&resource->resource_lock);
+}
+
+static void acpi_power_remove_dependent(acpi_handle rhandle,
+ struct acpi_device *adev)
+{
+ struct acpi_power_dependent_device *dep;
+ struct acpi_power_resource *resource;
+ struct work_struct *work = NULL;
+
+ if (!rhandle || !adev || acpi_power_get_context(rhandle, &resource))
+ return;
+
+ mutex_lock(&resource->resource_lock);
+
+ list_for_each_entry(dep, &resource->dependent, node)
+ if (dep->adev == adev) {
+ list_del(&dep->node);
+ work = &dep->work;
+ break;
+ }
+
+ mutex_unlock(&resource->resource_lock);
+
+ if (work) {
+ cancel_work_sync(work);
+ kfree(dep);
+ }
+}
+
+void acpi_power_add_remove_device(struct acpi_device *adev, bool add)
+{
+ if (adev->power.flags.power_resources) {
+ struct acpi_device_power_state *ps;
+ int j;
+
+ ps = &adev->power.states[ACPI_STATE_D0];
+ for (j = 0; j < ps->resources.count; j++) {
+ acpi_handle rhandle = ps->resources.handles[j];
+
+ if (add)
+ acpi_power_add_dependent(rhandle, adev);
else
- prev->next = curr->next;
-
- kfree(curr);
- break;
- }
-
- prev = curr;
- curr = curr->next;
- }
- mutex_unlock(&resource->devices_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]);
-}
-EXPORT_SYMBOL_GPL(acpi_power_resource_unregister_device);
-
-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->devices_lock);
- power_resource_device->next = resource->devices;
- resource->devices = power_resource_device;
- mutex_unlock(&resource->devices_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 || !acpi_dev->power.flags.power_resources)
- return -ENODEV;
-
- 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;
+ acpi_power_remove_dependent(rhandle, adev);
}
}
-
- return ret;
}
-EXPORT_SYMBOL_GPL(acpi_power_resource_register_device);
+
+/* --------------------------------------------------------------------------
+ Device Power Management
+ -------------------------------------------------------------------------- */
/**
* acpi_device_sleep_wake - execute _DSW (Device Sleep Wake) or (deprecated in
@@ -623,10 +572,6 @@
return err;
}
-/* --------------------------------------------------------------------------
- Device Power Management
- -------------------------------------------------------------------------- */
-
int acpi_power_get_inferred_state(struct acpi_device *device, int *state)
{
int result = 0;
@@ -725,7 +670,7 @@
resource->device = device;
mutex_init(&resource->resource_lock);
- mutex_init(&resource->devices_lock);
+ INIT_LIST_HEAD(&resource->dependent);
strcpy(resource->name, device->pnp.bus_id);
strcpy(acpi_device_name(device), ACPI_POWER_DEVICE_NAME);
strcpy(acpi_device_class(device), ACPI_POWER_CLASS);