ACPI: attach thermal zone info

Intel menlow driver needs to get the pointer of themal_zone_device
structure of an ACPI thermal zone.
Attach this to each ACPI thermal zone device object.

Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Thomas Sujith <sujith.thomas@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>

drivers/acpi/bus.c

@@ -122,6 +122,31 @@ int acpi_bus_get_status(struct acpi_device *device)
 
 EXPORT_SYMBOL(acpi_bus_get_status);
 
+void acpi_bus_private_data_handler(acpi_handle handle,
+				   u32 function, void *context)
+{
+	return;
+}
+EXPORT_SYMBOL(acpi_bus_private_data_handler);
+
+int acpi_bus_get_private_data(acpi_handle handle, void **data)
+{
+	acpi_status status = AE_OK;
+
+	if (!*data)
+		return -EINVAL;
+
+	status = acpi_get_data(handle, acpi_bus_private_data_handler, data);
+	if (ACPI_FAILURE(status) || !*data) {
+		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No context for object [%p]\n",
+				handle));
+		return -ENODEV;
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL(acpi_bus_get_private_data);
+
 /* --------------------------------------------------------------------------
                                  Power Management
    -------------------------------------------------------------------------- */

drivers/acpi/thermal.c

@@ -1101,6 +1101,7 @@ static int acpi_thermal_register_thermal_zone(struct acpi_thermal *tz)
 {
 	int trips = 0;
 	int result;
+	acpi_status status;
 	int i;
 
 	if (tz->trips.critical.flags.valid)
@@ -1129,6 +1130,15 @@ static int acpi_thermal_register_thermal_zone(struct acpi_thermal *tz)
 	if (result)
 		return result;
 
+	status = acpi_attach_data(tz->device->handle,
+				  acpi_bus_private_data_handler,
+				  tz->thermal_zone);
+	if (ACPI_FAILURE(status)) {
+		ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
+				"Error attaching device data\n"));
+		return -ENODEV;
+	}
+
 	tz->tz_enabled = 1;
 
 	printk(KERN_INFO PREFIX "%s is registered as thermal_zone%d\n",
@@ -1142,6 +1152,7 @@ static void acpi_thermal_unregister_thermal_zone(struct acpi_thermal *tz)
 	sysfs_remove_link(&tz->thermal_zone->device.kobj, "device");
 	thermal_zone_device_unregister(tz->thermal_zone);
 	tz->thermal_zone = NULL;
+	acpi_detach_data(tz->device->handle, acpi_bus_private_data_handler);
 }
 
 

include/acpi/acpi_bus.h

@@ -321,6 +321,8 @@ struct acpi_bus_event {
 
 extern struct kobject *acpi_kobj;
 extern int acpi_bus_generate_netlink_event(const char*, const char*, u8, int);
+void acpi_bus_private_data_handler(acpi_handle, u32, void *);
+int acpi_bus_get_private_data(acpi_handle, void **);
 /*
  * External Functions
  */