[PATCH] Add driver_for_each_device().

Now there's an iterator for accessing each device bound to a driver.
Signed-off-by: Patrick Mochel <mochel@digitalimplant.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

Index: linux-2.6.12-rc2/drivers/base/driver.c
===================================================================

drivers/base/driver.c

@@ -18,6 +18,41 @@
 #define to_dev(node) container_of(node, struct device, driver_list)
 #define to_drv(obj) container_of(obj, struct device_driver, kobj)
 
+
+/**
+ *	driver_for_each_device - Iterator for devices bound to a driver.
+ *	@drv:	Driver we're iterating.
+ *	@data:	Data to pass to the callback.
+ *	@fn:	Function to call for each device.
+ *
+ *	Take the bus's rwsem and iterate over the @drv's list of devices,
+ *	calling @fn for each one.
+ */
+
+int driver_for_each_device(struct device_driver * drv, struct device * start, 
+			   void * data, int (*fn)(struct device *, void *))
+{
+	struct list_head * head;
+	struct device * dev;
+	int error = 0;
+
+	down_read(&drv->bus->subsys.rwsem);
+	head = &drv->devices;
+	dev = list_prepare_entry(start, head, driver_list);
+	list_for_each_entry_continue(dev, head, driver_list) {
+		get_device(dev);
+		error = fn(dev, data);
+		put_device(dev);
+		if (error)
+			break;
+	}
+	up_read(&drv->bus->subsys.rwsem);
+	return error;
+}
+
+EXPORT_SYMBOL(driver_for_each_device);
+
+
 /**
  *	driver_create_file - create sysfs file for driver.
  *	@drv:	driver.

include/linux/device.h

@@ -136,6 +136,9 @@ struct driver_attribute driver_attr_##_name = __ATTR(_name,_mode,_show,_store)
 extern int driver_create_file(struct device_driver *, struct driver_attribute *);
 extern void driver_remove_file(struct device_driver *, struct driver_attribute *);
 
+extern int driver_for_each_device(struct device_driver * drv, struct device * start,
+				  void * data, int (*fn)(struct device *, void *));
+
 
 /*
  * device classes