[PATCH] Driver core: add hotplug support for class_simple

This is needed by the DRI code.

drivers/base/class_simple.c

@@ -169,6 +169,24 @@ struct class_device *class_simple_device_add(struct class_simple *cs, dev_t dev,
 }
 EXPORT_SYMBOL(class_simple_device_add);
 
+/**
+ * class_simple_set_hotplug - set the hotplug callback in the embedded struct class
+ * @cs: pointer to the struct class_simple to hold the pointer
+ * @hotplug: function pointer to the hotplug function
+ *
+ * Implement and set a hotplug function to add environment variables specific to this 
+ * class on the hotplug event.
+ */
+int class_simple_set_hotplug(struct class_simple *cs, 
+	int (*hotplug)(struct class_device *dev, char **envp, int num_envp, char *buffer, int buffer_size))
+{
+	if ((cs == NULL) || (IS_ERR(cs)))
+		return -ENODEV;
+	cs->class.hotplug = hotplug;
+	return 0;
+}
+EXPORT_SYMBOL(class_simple_set_hotplug);
+
 /**
  * class_simple_device_remove - removes a class device that was created with class_simple_device_add()
  * @dev: the dev_t of the device that was previously registered.

include/linux/device.h

@@ -253,6 +253,8 @@ extern struct class_simple *class_simple_create(struct module *owner, char *name
 extern void class_simple_destroy(struct class_simple *cs);
 extern struct class_device *class_simple_device_add(struct class_simple *cs, dev_t dev, struct device *device, const char *fmt, ...)
 	__attribute__((format(printf,4,5)));
+extern int class_simple_set_hotplug(struct class_simple *, 
+	int (*hotplug)(struct class_device *dev, char **envp, int num_envp, char *buffer, int buffer_size));
 extern void class_simple_device_remove(dev_t dev);