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-rw-r--r--Documentation/ABI/testing/sysfs-devices-resource_in_use12
-rw-r--r--drivers/acpi/power.c26
-rw-r--r--drivers/acpi/scan.c3
-rw-r--r--include/acpi/acpi_bus.h1
4 files changed, 41 insertions, 1 deletions
diff --git a/Documentation/ABI/testing/sysfs-devices-resource_in_use b/Documentation/ABI/testing/sysfs-devices-resource_in_use
new file mode 100644
index 000000000000..b4a3bc5922a3
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-devices-resource_in_use
@@ -0,0 +1,12 @@
+What: /sys/devices/.../resource_in_use
+Date: January 2013
+Contact: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
+Description:
+ The /sys/devices/.../resource_in_use attribute is only present
+ for device objects representing ACPI power resources.
+
+ If present, it contains a number (0 or 1) representing the
+ current status of the given power resource (0 means that the
+ resource is not in use and therefore it has been turned off).
+
+ This attribute is read-only.
diff --git a/drivers/acpi/power.c b/drivers/acpi/power.c
index 3f16dd4db23e..946720a4db57 100644
--- a/drivers/acpi/power.c
+++ b/drivers/acpi/power.c
@@ -87,6 +87,12 @@ static DEFINE_MUTEX(power_resource_list_lock);
Power Resource Management
-------------------------------------------------------------------------- */
+static inline
+struct acpi_power_resource *to_power_resource(struct acpi_device *device)
+{
+ return container_of(device, struct acpi_power_resource, device);
+}
+
static struct acpi_power_resource *acpi_power_get_context(acpi_handle handle)
{
struct acpi_device *device;
@@ -94,7 +100,7 @@ static struct acpi_power_resource *acpi_power_get_context(acpi_handle handle)
if (acpi_bus_get_device(handle, &device))
return NULL;
- return container_of(device, struct acpi_power_resource, device);
+ return to_power_resource(device);
}
static int acpi_power_resources_list_add(acpi_handle handle,
@@ -678,6 +684,21 @@ static void acpi_release_power_resource(struct device *dev)
kfree(resource);
}
+static ssize_t acpi_power_in_use_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf) {
+ struct acpi_power_resource *resource;
+
+ resource = to_power_resource(to_acpi_device(dev));
+ return sprintf(buf, "%u\n", !!resource->ref_count);
+}
+static DEVICE_ATTR(resource_in_use, 0444, acpi_power_in_use_show, NULL);
+
+static void acpi_power_sysfs_remove(struct acpi_device *device)
+{
+ device_remove_file(&device->dev, &dev_attr_resource_in_use);
+}
+
int acpi_add_power_resource(acpi_handle handle)
{
struct acpi_power_resource *resource;
@@ -725,6 +746,9 @@ int acpi_add_power_resource(acpi_handle handle)
if (result)
goto err;
+ if (!device_create_file(&device->dev, &dev_attr_resource_in_use))
+ device->remove = acpi_power_sysfs_remove;
+
mutex_lock(&power_resource_list_lock);
list_add(&resource->list_node, &acpi_power_resource_list);
mutex_unlock(&power_resource_list_lock);
diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c
index 9761d589f3f5..9801837876b7 100644
--- a/drivers/acpi/scan.c
+++ b/drivers/acpi/scan.c
@@ -791,6 +791,9 @@ static void acpi_device_unregister(struct acpi_device *device)
acpi_power_add_remove_device(device, false);
acpi_device_remove_files(device);
+ if (device->remove)
+ device->remove(device);
+
device_del(&device->dev);
/*
* Drop the reference counts of all power resources the device depends
diff --git a/include/acpi/acpi_bus.h b/include/acpi/acpi_bus.h
index fca1b9cb27d9..aef56a9f4e70 100644
--- a/include/acpi/acpi_bus.h
+++ b/include/acpi/acpi_bus.h
@@ -280,6 +280,7 @@ struct acpi_device {
struct mutex physical_node_lock;
DECLARE_BITMAP(physical_node_id_bitmap, ACPI_MAX_PHYSICAL_NODE);
struct list_head power_dependent;
+ void (*remove)(struct acpi_device *);
};
static inline void *acpi_driver_data(struct acpi_device *d)