[S390] cio: introduce css_settle

Introduce the css_driver callback settle which can be implemented
by a subchannel driver to wait for the subchannel type specific
asynchronous work to finish.
In channel_subsystem_init_sync we call that for each subchannel
driver.

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

1 files changed, 2 insertions, 0 deletions

diff --git a/drivers/s390/cio/css.h b/drivers/s390/cio/css.h
index 9763eeec7458..54acdaade86e 100644
--- a/drivers/s390/cio/css.h
+++ b/drivers/s390/cio/css.h
@@ -75,6 +75,7 @@ struct chp_link;
  * @freeze: callback for freezing during hibernation snapshotting
  * @thaw: undo work done in @freeze
  * @restore: callback for restoring after hibernation
+ * @settle: wait for asynchronous work to finish
  * @name: name of the device driver
  */
 struct css_driver {
@@ -92,6 +93,7 @@ struct css_driver {
         int (*freeze)(struct subchannel *);
         int (*thaw) (struct subchannel *);
         int (*restore)(struct subchannel *);
+        void (*settle)(void);
         const char *name;
 };