1 files changed, 22 insertions, 0 deletions

diff --git a/include/linux/device.h b/include/linux/device.h
index 9d4835a8f8b8..bcf8c0d4cd98 100644
--- a/include/linux/device.h
+++ b/include/linux/device.h
@@ -71,6 +71,10 @@ extern void bus_remove_file(struct bus_type *, struct bus_attribute *);
  *              the specific driver's probe to initial the matched device.
  * @remove:     Called when a device removed from this bus.
  * @shutdown:   Called at shut-down time to quiesce the device.
+ *
+ * @online:     Called to put the device back online (after offlining it).
+ * @offline:    Called to put the device offline for hot-removal. May fail.
+ *
  * @suspend:    Called when a device on this bus wants to go to sleep mode.
  * @resume:     Called to bring a device on this bus out of sleep mode.
  * @pm:         Power management operations of this bus, callback the specific
@@ -105,6 +109,9 @@ struct bus_type {
         int (*remove)(struct device *dev);
         void (*shutdown)(struct device *dev);
 
+        int (*online)(struct device *dev);
+        int (*offline)(struct device *dev);
+
         int (*suspend)(struct device *dev, pm_message_t state);
         int (*resume)(struct device *dev);
 
@@ -652,6 +659,9 @@ struct acpi_dev_node {
  *              device (i.e. the bus driver that discovered the device).
  * @iommu_group: IOMMU group the device belongs to.
  *
+ * @offline_disabled: If set, the device is permanently online.
+ * @offline:    Set after successful invocation of bus type's .offline().
+ *
  * At the lowest level, every device in a Linux system is represented by an
  * instance of struct device. The device structure contains the information
  * that the device model core needs to model the system. Most subsystems,
@@ -723,6 +733,9 @@ struct device {
 
         void    (*release)(struct device *dev);
         struct iommu_group      *iommu_group;
+
+        bool                    offline_disabled:1;
+        bool                    offline:1;
 };
 
 static inline struct device *kobj_to_dev(struct kobject *kobj)
@@ -859,6 +872,15 @@ extern const char *device_get_devnode(struct device *dev,
 extern void *dev_get_drvdata(const struct device *dev);
 extern int dev_set_drvdata(struct device *dev, void *data);
 
+static inline bool device_supports_offline(struct device *dev)
+{
+        return dev->bus && dev->bus->offline && dev->bus->online;
+}
+
+extern void lock_device_hotplug(void);
+extern void unlock_device_hotplug(void);
+extern int device_offline(struct device *dev);
+extern int device_online(struct device *dev);
 /*
  * Root device objects for grouping under /sys/devices
  */