ACPI: Remove unnecessary objects and code from drivers/acpi/system.c

First, we remove acpi_system_driver, since it's not really a driver, and making it its own 
object is just silly. This allows us to not have to register it, and we can hence remove
the add and remove callbacks. 

For initialization, acpi_system_add_fs() has been inlined in acpi_system_init(). The proc file
creation was cleaned up to use create_proc_read_entry() where possible. Any failures now
result in a goto Error, which prints the error message previously replicated after each
failure. We also remove all the files that were created if that happens. acpi_system_init()
was made a subsys_initcall and declared static. 

The acpi_system_exit() code and friends was removed, since it's never, ever called. 

drivers/acpi/acpi_drivers.h

@@ -257,14 +257,6 @@ int acpi_processor_set_thermal_limit(acpi_handle handle, int type);
 #define ACPI_SYSTEM_FILE_DEBUG_LAYER	"debug_layer"
 #define ACPI_SYSTEM_FILE_DEBUG_LEVEL	"debug_level"
 
-#ifdef CONFIG_ACPI_SYSTEM
-
-int acpi_system_init (void);
-void acpi_system_exit (void);
-
-#endif
-
-
 /* --------------------------------------------------------------------------
                                  Thermal Zone
    -------------------------------------------------------------------------- */

drivers/acpi/bus.c

@@ -1953,7 +1953,6 @@ acpi_bus_init (void)
 	 * Install drivers required for proper enumeration of the
 	 * ACPI namespace.
 	 */
-	acpi_system_init();	/* ACPI System */
 	acpi_power_init();	/* ACPI Bus Power Management */
 #ifdef CONFIG_ACPI_EC
 	acpi_ec_init();		/* ACPI Embedded Controller */
@@ -2010,7 +2009,6 @@ acpi_bus_exit (void)
 	acpi_ec_exit();
 #endif
 	acpi_power_exit();
-	acpi_system_exit();
 
 	acpi_bus_remove(acpi_root, ACPI_BUS_REMOVAL_NORMAL);
 

drivers/acpi/system.c

@@ -37,19 +37,6 @@ ACPI_MODULE_NAME		("acpi_system")
 
 extern FADT_DESCRIPTOR		acpi_fadt;
 
-static int acpi_system_add (struct acpi_device *device);
-static int acpi_system_remove (struct acpi_device *device, int type);
-
-static struct acpi_driver acpi_system_driver = {
-	.name =		ACPI_SYSTEM_DRIVER_NAME,
-	.class =	ACPI_SYSTEM_CLASS,
-	.ids =		ACPI_SYSTEM_HID,
-	.ops =		{
-				.add =		acpi_system_add,
-				.remove =	acpi_system_remove
-			},
-};
-
 /* Global vars for handling event proc entry */
 static spinlock_t		acpi_system_event_lock = SPIN_LOCK_UNLOCKED;
 int				event_is_open = 0;
@@ -352,182 +339,85 @@ acpi_system_write_debug (
 
 #endif /* ACPI_DEBUG */
 
-
-static int
-acpi_system_add_fs (
-	struct acpi_device	*device)
+static int __init acpi_system_init (void)
 {
-	struct proc_dir_entry	*entry = NULL;
-
-	ACPI_FUNCTION_TRACE("acpi_system_add_fs");
+	struct proc_dir_entry	*entry;
+	int error = 0;
+	char * name;
 
-	if (!device)
-		return_VALUE(-EINVAL);
+	ACPI_FUNCTION_TRACE("acpi_system_init");
 
 	/* 'info' [R] */
-	entry = create_proc_entry(ACPI_SYSTEM_FILE_INFO,
-		S_IRUGO, acpi_device_dir(device));
+	name = ACPI_SYSTEM_FILE_INFO;
+	entry = create_proc_read_entry(name,
+		S_IRUGO, acpi_root_dir, acpi_system_read_info,NULL);
 	if (!entry)
-		ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
-			"Unable to create '%s' fs entry\n",
-			ACPI_SYSTEM_FILE_INFO));
-	else {
-		entry->read_proc = acpi_system_read_info;
-		entry->data = acpi_driver_data(device);
-	}
+		goto Error;
 
 	/* 'dsdt' [R] */
-	entry = create_proc_entry(ACPI_SYSTEM_FILE_DSDT,
-		S_IRUSR, acpi_device_dir(device));
-	if (!entry)
-		ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
-			"Unable to create '%s' fs entry\n",
-			ACPI_SYSTEM_FILE_DSDT));
-	else
+	name = ACPI_SYSTEM_FILE_DSDT;
+	entry = create_proc_entry(name, S_IRUSR, acpi_root_dir);
+	if (entry)
 		entry->proc_fops = &acpi_system_dsdt_ops;
+	else 
+		goto Error;
 
 	/* 'fadt' [R] */
-	entry = create_proc_entry(ACPI_SYSTEM_FILE_FADT,
-		S_IRUSR, acpi_device_dir(device));
-	if (!entry)
-		ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
-			"Unable to create '%s' fs entry\n",
-			ACPI_SYSTEM_FILE_FADT));
-	else
+	name = ACPI_SYSTEM_FILE_FADT;
+	entry = create_proc_entry(name, S_IRUSR, acpi_root_dir);
+	if (entry)
 		entry->proc_fops = &acpi_system_fadt_ops;
+	else
+		goto Error;
 
 	/* 'event' [R] */
-	entry = create_proc_entry(ACPI_SYSTEM_FILE_EVENT,
-		S_IRUSR, acpi_device_dir(device));
-	if (!entry)
-		ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
-			"Unable to create '%s' fs entry\n",
-			ACPI_SYSTEM_FILE_EVENT));
-	else
+	name = ACPI_SYSTEM_FILE_EVENT;
+	entry = create_proc_entry(name, S_IRUSR, acpi_root_dir);
+	if (entry)
 		entry->proc_fops = &acpi_system_event_ops;
+	else
+		goto Error;
 
 #ifdef ACPI_DEBUG
 
 	/* 'debug_layer' [R/W] */
-	entry = create_proc_entry(ACPI_SYSTEM_FILE_DEBUG_LAYER,
-		S_IFREG|S_IRUGO|S_IWUSR, acpi_device_dir(device));
-	if (!entry)
-		ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
-			"Unable to create '%s' fs entry\n",
-			ACPI_SYSTEM_FILE_DEBUG_LAYER));
-	else {
-		entry->read_proc  = acpi_system_read_debug;
+	name = ACPI_SYSTEM_FILE_DEBUG_LAYER;
+	entry = create_proc_read_entry(name, S_IFREG|S_IRUGO|S_IWUSR, acpi_root_dir,
+				       acpi_system_read_debug,(void *)0);
+	if (entry)
 		entry->write_proc = acpi_system_write_debug;
-		entry->data = (void *) 0;
-	}
+	else
+		goto Error;
 
 	/* 'debug_level' [R/W] */
-	entry = create_proc_entry(ACPI_SYSTEM_FILE_DEBUG_LEVEL,
-		S_IFREG|S_IRUGO|S_IWUSR, acpi_device_dir(device));
-	if (!entry)
-		ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
-			"Unable to create '%s' fs entry\n",
-			ACPI_SYSTEM_FILE_DEBUG_LEVEL));
-	else {
-		entry->read_proc  = acpi_system_read_debug;
+	name = ACPI_SYSTEM_FILE_DEBUG_LEVEL;
+	entry = create_proc_read_entry(name, S_IFREG|S_IRUGO|S_IWUSR, acpi_root_dir,
+				       acpi_system_read_debug, (void *)1);
+	if (entry) 
 		entry->write_proc = acpi_system_write_debug;
-		entry->data = (void *) 1;
-	}
+	else
+		goto Error;
 
 #endif /*ACPI_DEBUG*/
 
-	return_VALUE(0);
-}
+ Done:
+	return_VALUE(error);
 
-
-static int
-acpi_system_remove_fs (
-	struct acpi_device	*device)
-{
-	ACPI_FUNCTION_TRACE("acpi_system_remove_fs");
-
-	if (!device)
-		return_VALUE(-EINVAL);
-
-	remove_proc_entry(ACPI_SYSTEM_FILE_INFO, acpi_device_dir(device));
-	remove_proc_entry(ACPI_SYSTEM_FILE_DSDT, acpi_device_dir(device));
-	remove_proc_entry(ACPI_SYSTEM_FILE_EVENT, acpi_device_dir(device));
+ Error:
+	ACPI_DEBUG_PRINT((ACPI_DB_ERROR, 
+			 "Unable to create '%s' proc fs entry\n", name));
 #ifdef ACPI_DEBUG
-	remove_proc_entry(ACPI_SYSTEM_FILE_DEBUG_LAYER,
-		acpi_device_dir(device));
-	remove_proc_entry(ACPI_SYSTEM_FILE_DEBUG_LEVEL,
-		acpi_device_dir(device));
+	remove_proc_entry(ACPI_SYSTEM_FILE_DEBUG_LEVEL, acpi_root_dir);
+	remove_proc_entry(ACPI_SYSTEM_FILE_DEBUG_LAYER, acpi_root_dir);
 #endif
+	remove_proc_entry(ACPI_SYSTEM_FILE_EVENT, acpi_root_dir);
+	remove_proc_entry(ACPI_SYSTEM_FILE_FADT, acpi_root_dir);
+	remove_proc_entry(ACPI_SYSTEM_FILE_DSDT, acpi_root_dir);
+	remove_proc_entry(ACPI_SYSTEM_FILE_INFO, acpi_root_dir);
 
-	return_VALUE(0);
+	error = -EINVAL;
+	goto Done;
 }
 
 
-/* --------------------------------------------------------------------------
-                                 Driver Interface
-   -------------------------------------------------------------------------- */
-
-static int
-acpi_system_add (
-	struct acpi_device	*device)
-{
-	int			result = 0;
-
-	ACPI_FUNCTION_TRACE("acpi_system_add");
-
-	if (!device)
-		return_VALUE(-EINVAL);
-
-	sprintf(acpi_device_name(device), "%s", ACPI_SYSTEM_DEVICE_NAME);
-	sprintf(acpi_device_class(device), "%s", ACPI_SYSTEM_CLASS);
-
-	result = acpi_system_add_fs(device);
-
-	return_VALUE(result);
-}
-
-
-static int
-acpi_system_remove (
-	struct acpi_device	*device,
-	int			type)
-{
-	struct acpi_system	*system = NULL;
-
-	ACPI_FUNCTION_TRACE("acpi_system_remove");
-
-	if (!device || !acpi_driver_data(device))
-		return_VALUE(-EINVAL);
-
-	system = (struct acpi_system *) acpi_driver_data(device);
-
-	acpi_system_remove_fs(device);
-
-	kfree(system);
-
-	return 0;
-}
-
-
-int __init
-acpi_system_init (void)
-{
-	int			result = 0;
-
-	ACPI_FUNCTION_TRACE("acpi_system_init");
-
-	result = acpi_bus_register_driver(&acpi_system_driver);
-	if (result < 0)
-		return_VALUE(-ENODEV);
-
-	return_VALUE(0);
-}
-
-
-void __exit
-acpi_system_exit (void)
-{
-	ACPI_FUNCTION_TRACE("acpi_system_exit");
-	acpi_bus_unregister_driver(&acpi_system_driver);
-	return_VOID;
-}
+subsys_initcall(acpi_system_init);