[S390] pm: dasd power management callbacks.

Introduce the power management callbacks to the dasd driver. On suspend
the dasd devices are stopped and removed from the focus of alias
management.
On resume they are reinitialized by rereading the device characteristics
and adding the device to the alias management.
In case the device has gone away during suspend it will caught in the
suspend state with stopped flag set to UNRESUMED. After it appears again
the restore function is called again.

Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

1 files changed, 11 insertions, 2 deletions

diff --git a/drivers/s390/block/dasd_int.h b/drivers/s390/block/dasd_int.h
index f97ceb795078..fd63b2f2bda9 100644
--- a/drivers/s390/block/dasd_int.h
+++ b/drivers/s390/block/dasd_int.h
@@ -4,8 +4,7 @@
  *                  Horst Hummel <Horst.Hummel@de.ibm.com>
  *                  Martin Schwidefsky <schwidefsky@de.ibm.com>
  * Bugreports.to..: <Linux390@de.ibm.com>
- * (C) IBM Corporation, IBM Deutschland Entwicklung GmbH, 1999,2000
- *
+ * Copyright IBM Corp. 1999, 2009
  */
 
 #ifndef DASD_INT_H
@@ -295,6 +294,10 @@ struct dasd_discipline {
         int (*fill_geometry) (struct dasd_block *, struct hd_geometry *);
         int (*fill_info) (struct dasd_device *, struct dasd_information2_t *);
         int (*ioctl) (struct dasd_block *, unsigned int, void __user *);
+
+        /* suspend/resume functions */
+        int (*freeze) (struct dasd_device *);
+        int (*restore) (struct dasd_device *);
 };
 
 extern struct dasd_discipline *dasd_diag_discipline_pointer;
@@ -367,6 +370,7 @@ struct dasd_device {
         atomic_t tasklet_scheduled;
         struct tasklet_struct tasklet;
         struct work_struct kick_work;
+        struct work_struct restore_device;
         struct timer_list timer;
 
         debug_info_t *debug_area;
@@ -410,6 +414,8 @@ struct dasd_block {
 #define DASD_STOPPED_PENDING 4         /* long busy */
 #define DASD_STOPPED_DC_WAIT 8         /* disconnected, wait */
 #define DASD_STOPPED_SU      16        /* summary unit check handling */
+#define DASD_STOPPED_PM      32        /* pm state transition */
+#define DASD_UNRESUMED_PM    64        /* pm resume failed state */
 
 /* per device flags */
 #define DASD_FLAG_OFFLINE       3       /* device is in offline processing */
@@ -556,6 +562,7 @@ void dasd_free_block(struct dasd_block *);
 void dasd_enable_device(struct dasd_device *);
 void dasd_set_target_state(struct dasd_device *, int);
 void dasd_kick_device(struct dasd_device *);
+void dasd_restore_device(struct dasd_device *);
 
 void dasd_add_request_head(struct dasd_ccw_req *);
 void dasd_add_request_tail(struct dasd_ccw_req *);
@@ -578,6 +585,8 @@ int dasd_generic_set_online(struct ccw_device *, struct dasd_discipline *);
 int dasd_generic_set_offline (struct ccw_device *cdev);
 int dasd_generic_notify(struct ccw_device *, int);
 void dasd_generic_handle_state_change(struct dasd_device *);
+int dasd_generic_pm_freeze(struct ccw_device *);
+int dasd_generic_restore_device(struct ccw_device *);
 
 int dasd_generic_read_dev_chars(struct dasd_device *, char *, void *, int);
 char *dasd_get_sense(struct irb *);