Driver core: add notification of bus events

[mirror_ubuntu-zesty-kernel.git] / include / linux / device.h

diff --git a/include/linux/device.h b/include/linux/device.h
index 662e6a10144e5b453b2ad11b02fc7314bd33816e..b00e027113930900956afe2902b54422088f6c37 100644 (file)
--- a/include/linux/device.h
+++ b/include/linux/device.h
@@ -42,6 +42,8 @@ struct bus_type {
        struct klist            klist_devices;
        struct klist            klist_drivers;
 
+       struct blocking_notifier_head bus_notifier;
+
        struct bus_attribute    * bus_attrs;
        struct device_attribute * dev_attrs;
        struct driver_attribute * drv_attrs;
@@ -75,6 +77,29 @@ int __must_check bus_for_each_drv(struct bus_type *bus,
                struct device_driver *start, void *data,
                int (*fn)(struct device_driver *, void *));
 
+/*
+ * Bus notifiers: Get notified of addition/removal of devices
+ * and binding/unbinding of drivers to devices.
+ * In the long run, it should be a replacement for the platform
+ * notify hooks.
+ */
+struct notifier_block;
+
+extern int bus_register_notifier(struct bus_type *bus,
+                                struct notifier_block *nb);
+extern int bus_unregister_notifier(struct bus_type *bus,
+                                  struct notifier_block *nb);
+
+/* All 4 notifers below get called with the target struct device *
+ * as an argument. Note that those functions are likely to be called
+ * with the device semaphore held in the core, so be careful.
+ */
+#define BUS_NOTIFY_ADD_DEVICE          0x00000001 /* device added */
+#define BUS_NOTIFY_DEL_DEVICE          0x00000002 /* device removed */
+#define BUS_NOTIFY_BOUND_DRIVER                0x00000003 /* driver bound to device */
+#define BUS_NOTIFY_UNBIND_DRIVER       0x00000004 /* driver about to be
+                                                     unbound */
+
 /* driverfs interface for exporting bus attributes */
 
 struct bus_attribute {
@@ -393,7 +418,7 @@ extern void device_unregister(struct device * dev);
 extern void device_initialize(struct device * dev);
 extern int __must_check device_add(struct device * dev);
 extern void device_del(struct device * dev);
-extern int __must_check device_for_each_child(struct device *, void *,
+extern int device_for_each_child(struct device *, void *,
                     int (*fn)(struct device *, void *));
 extern int device_rename(struct device *dev, char *new_name);