ACPI: Add acpi_bus_attach_private_data() to attach data to ACPI handle

There is already acpi_bus_get_private_data() to get ACPI handle data
which is associated with acpi_bus_private_data_handler(). This patch
is to add acpi_bus_attach_private_data() to make a pair and facilitate
to attach and get data to/from ACPI handle.

Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Lan Tianyu <tianyu.lan@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

2 files changed, 26 insertions, 4 deletions

diff --git a/drivers/acpi/bus.c b/drivers/acpi/bus.c
index cf925c4f36b7..8445d570f60a 100644
--- a/drivers/acpi/bus.c
+++ b/drivers/acpi/bus.c
@@ -132,6 +132,21 @@ void acpi_bus_private_data_handler(acpi_handle handle,
 }
 EXPORT_SYMBOL(acpi_bus_private_data_handler);
 
+int acpi_bus_attach_private_data(acpi_handle handle, void *data)
+{
+        acpi_status status;
+
+        status = acpi_attach_data(handle,
+                        acpi_bus_private_data_handler, data);
+        if (ACPI_FAILURE(status)) {
+                acpi_handle_debug(handle, "Error attaching device data\n");
+                return -ENODEV;
+        }
+
+        return 0;
+}
+EXPORT_SYMBOL_GPL(acpi_bus_attach_private_data);
+
 int acpi_bus_get_private_data(acpi_handle handle, void **data)
 {
         acpi_status status;
@@ -140,15 +155,20 @@ int acpi_bus_get_private_data(acpi_handle handle, void **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));
+        if (ACPI_FAILURE(status)) {
+                acpi_handle_debug(handle, "No context for object\n");
                 return -ENODEV;
         }
 
         return 0;
 }
-EXPORT_SYMBOL(acpi_bus_get_private_data);
+EXPORT_SYMBOL_GPL(acpi_bus_get_private_data);
+
+void acpi_bus_detach_private_data(acpi_handle handle)
+{
+        acpi_detach_data(handle, acpi_bus_private_data_handler);
+}
+EXPORT_SYMBOL_GPL(acpi_bus_detach_private_data);
 
 void acpi_bus_no_hotplug(acpi_handle handle)
 {
diff --git a/include/acpi/acpi_bus.h b/include/acpi/acpi_bus.h
index 84a2e29a2314..d2006ca31dba 100644
--- a/include/acpi/acpi_bus.h
+++ b/include/acpi/acpi_bus.h
@@ -406,6 +406,8 @@ 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, void *);
 int acpi_bus_get_private_data(acpi_handle, void **);
+int acpi_bus_attach_private_data(acpi_handle, void *);
+void acpi_bus_detach_private_data(acpi_handle);
 void acpi_bus_no_hotplug(acpi_handle handle);
 extern int acpi_notifier_call_chain(struct acpi_device *, u32, u32);
 extern int register_acpi_notifier(struct notifier_block *);