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path: root/drivers/acpi/power.c
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Diffstat (limited to 'drivers/acpi/power.c')
-rw-r--r--drivers/acpi/power.c61
1 files changed, 47 insertions, 14 deletions
diff --git a/drivers/acpi/power.c b/drivers/acpi/power.c
index 32974b575e46..97c9a94a1a30 100644
--- a/drivers/acpi/power.c
+++ b/drivers/acpi/power.c
@@ -52,6 +52,7 @@ struct acpi_power_resource {
u32 system_level;
u32 order;
unsigned int ref_count;
+ unsigned int users;
bool wakeup_enabled;
struct mutex resource_lock;
struct list_head dependents;
@@ -147,6 +148,7 @@ int acpi_extract_power_resources(union acpi_object *package, unsigned int start,
for (i = start; i < package->package.count; i++) {
union acpi_object *element = &package->package.elements[i];
+ struct acpi_device *rdev;
acpi_handle rhandle;
if (element->type != ACPI_TYPE_LOCAL_REFERENCE) {
@@ -163,13 +165,16 @@ int acpi_extract_power_resources(union acpi_object *package, unsigned int start,
if (acpi_power_resource_is_dup(package, start, i))
continue;
- err = acpi_add_power_resource(rhandle);
- if (err)
+ rdev = acpi_add_power_resource(rhandle);
+ if (!rdev) {
+ err = -ENODEV;
break;
-
+ }
err = acpi_power_resources_list_add(rhandle, list);
if (err)
break;
+
+ to_power_resource(rdev)->users++;
}
if (err)
acpi_power_resources_list_free(list);
@@ -907,7 +912,7 @@ static void acpi_power_add_resource_to_list(struct acpi_power_resource *resource
mutex_unlock(&power_resource_list_lock);
}
-int acpi_add_power_resource(acpi_handle handle)
+struct acpi_device *acpi_add_power_resource(acpi_handle handle)
{
struct acpi_power_resource *resource;
struct acpi_device *device = NULL;
@@ -918,11 +923,11 @@ int acpi_add_power_resource(acpi_handle handle)
acpi_bus_get_device(handle, &device);
if (device)
- return 0;
+ return device;
resource = kzalloc(sizeof(*resource), GFP_KERNEL);
if (!resource)
- return -ENOMEM;
+ return NULL;
device = &resource->device;
acpi_init_device_object(device, handle, ACPI_BUS_TYPE_POWER);
@@ -959,11 +964,11 @@ int acpi_add_power_resource(acpi_handle handle)
acpi_power_add_resource_to_list(resource);
acpi_device_add_finalize(device);
- return 0;
+ return device;
err:
acpi_release_power_resource(&device->dev);
- return result;
+ return NULL;
}
#ifdef CONFIG_ACPI_SLEEP
@@ -995,8 +1000,40 @@ void acpi_resume_power_resources(void)
mutex_unlock(&power_resource_list_lock);
}
+#endif
+
+static void acpi_power_turn_off_if_unused(struct acpi_power_resource *resource,
+ bool init)
+{
+ if (resource->ref_count > 0)
+ return;
+
+ if (init) {
+ if (resource->users > 0)
+ return;
+ } else {
+ int result, state;
+
+ result = acpi_power_get_state(resource->device.handle, &state);
+ if (result || state == ACPI_POWER_RESOURCE_STATE_OFF)
+ return;
+ }
+
+ dev_info(&resource->device.dev, "Turning OFF\n");
+ __acpi_power_off(resource);
+}
-void acpi_turn_off_unused_power_resources(void)
+/**
+ * acpi_turn_off_unused_power_resources - Turn off power resources not in use.
+ * @init: Control switch.
+ *
+ * If @ainit is set, unconditionally turn off all of the ACPI power resources
+ * without any users.
+ *
+ * Otherwise, turn off all ACPI power resources without active references (that
+ * is, the ones that should be "off" at the moment) that are "on".
+ */
+void acpi_turn_off_unused_power_resources(bool init)
{
struct acpi_power_resource *resource;
@@ -1005,14 +1042,10 @@ void acpi_turn_off_unused_power_resources(void)
list_for_each_entry_reverse(resource, &acpi_power_resource_list, list_node) {
mutex_lock(&resource->resource_lock);
- if (!resource->ref_count) {
- dev_info(&resource->device.dev, "Turning OFF\n");
- __acpi_power_off(resource);
- }
+ acpi_power_turn_off_if_unused(resource, init);
mutex_unlock(&resource->resource_lock);
}
mutex_unlock(&power_resource_list_lock);
}
-#endif