[S390] pm: power management support for SCLP drivers.

The SCLP base driver defines a new notifier call back for all upper level SCLP
drivers, like the SCLP console, etc. This guarantees that in suspend first the
upper level drivers are suspended and afterwards the SCLP base driver. For
resume it is the other way round. The SCLP base driver itself registers a
new platform device at the platform bus and gets PM notifications via
the dev_pm_ops.

In suspend, the SCLP base driver switches off the receiver and sender mask
This is done in sclp_deactivate(). After suspend all new requests will be
rejected with -EIO and no more interrupts will be received, because the masks
are switched off. For resume the sender and receiver masks are reset in
the sclp_reactivate() function.

When the SCLP console is suspended, all new messages are cached in the
sclp console buffers. In resume, all the cached messages are written to the
console. In addition to that we have an early resume function that removes
the cached messages from the suspend image.

Signed-off-by: Michael Holzheu <holzheu@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

1 files changed, 17 insertions, 6 deletions

diff --git a/drivers/s390/char/sclp.h b/drivers/s390/char/sclp.h
index bac80e856f97..60e7cb07095b 100644
--- a/drivers/s390/char/sclp.h
+++ b/drivers/s390/char/sclp.h
@@ -1,10 +1,8 @@
 /*
- *  drivers/s390/char/sclp.h
+ * Copyright IBM Corp. 1999, 2009
  *
- *  S390 version
- *    Copyright (C) 1999 IBM Deutschland Entwicklung GmbH, IBM Corporation
- *    Author(s): Martin Peschke <mpeschke@de.ibm.com>
- *               Martin Schwidefsky <schwidefsky@de.ibm.com>
+ * Author(s): Martin Peschke <mpeschke@de.ibm.com>
+ *            Martin Schwidefsky <schwidefsky@de.ibm.com>
  */
 
 #ifndef __SCLP_H__
@@ -17,7 +15,7 @@
 
 /* maximum number of pages concerning our own memory management */
 #define MAX_KMEM_PAGES (sizeof(unsigned long) << 3)
-#define MAX_CONSOLE_PAGES       4
+#define MAX_CONSOLE_PAGES       6
 
 #define EVTYP_OPCMD             0x01
 #define EVTYP_MSG               0x02
@@ -68,6 +66,15 @@ typedef unsigned int sclp_cmdw_t;
 
 #define GDS_KEY_SELFDEFTEXTMSG  0x31
 
+enum sclp_pm_event {
+        SCLP_PM_EVENT_FREEZE,
+        SCLP_PM_EVENT_THAW,
+        SCLP_PM_EVENT_RESTORE,
+};
+
+#define SCLP_PANIC_PRIO         1
+#define SCLP_PANIC_PRIO_CLIENT  0
+
 typedef u32 sccb_mask_t;        /* ATTENTION: assumes 32bit mask !!! */
 
 struct sccb_header {
@@ -134,6 +141,10 @@ struct sclp_register {
         void (*state_change_fn)(struct sclp_register *);
         /* called for events in cp_receive_mask/sclp_receive_mask */
         void (*receiver_fn)(struct evbuf_header *);
+        /* called for power management events */
+        void (*pm_event_fn)(struct sclp_register *, enum sclp_pm_event);
+        /* pm event posted flag */
+        int pm_event_posted;
 };
 
 /* externals from sclp.c */