[S390] pm: con3270 power management callbacks.

Introduce the power management callbacks to the 3270 driver. On suspend
the current 3270 view is deactivated and for non-console 3270 device
the release callback is done. This disconnects the current tty /
fullscreen application from the 3270 device. On resume the current
view is reactivated, on the tty you get a fresh login.
If the system panics before the 3270 device has been resumed, the ccw
device for the 3270 console is reactivated with ccw_device_force_console.

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

1 files changed, 73 insertions, 11 deletions

diff --git a/drivers/s390/char/raw3270.c b/drivers/s390/char/raw3270.c
index 0b15cf107ec9..81c151b5f0ac 100644
--- a/drivers/s390/char/raw3270.c
+++ b/drivers/s390/char/raw3270.c
@@ -1,11 +1,10 @@
 /*
- *  drivers/s390/char/raw3270.c
- *    IBM/3270 Driver - core functions.
+ * IBM/3270 Driver - core functions.
  *
- *  Author(s):
- *    Original 3270 Code for 2.4 written by Richard Hitt (UTS Global)
- *    Rewritten for 2.5 by Martin Schwidefsky <schwidefsky@de.ibm.com>
- *      -- Copyright (C) 2003 IBM Deutschland Entwicklung GmbH, IBM Corporation
+ * Author(s):
+ *   Original 3270 Code for 2.4 written by Richard Hitt (UTS Global)
+ *   Rewritten for 2.5 by Martin Schwidefsky <schwidefsky@de.ibm.com>
+ *     Copyright IBM Corp. 2003, 2009
  */
 
 #include <linux/bootmem.h>
@@ -61,6 +60,7 @@ struct raw3270 {
 #define RAW3270_FLAGS_ATTN      2       /* Device sent an ATTN interrupt */
 #define RAW3270_FLAGS_READY     4       /* Device is useable by views */
 #define RAW3270_FLAGS_CONSOLE   8       /* Device is the console. */
+#define RAW3270_FLAGS_FROZEN    16      /* set if 3270 is frozen for suspend */
 
 /* Semaphore to protect global data of raw3270 (devices, views, etc). */
 static DEFINE_MUTEX(raw3270_mutex);
@@ -306,7 +306,8 @@ raw3270_start(struct raw3270_view *view, struct raw3270_request *rq)
 
         spin_lock_irqsave(get_ccwdev_lock(view->dev->cdev), flags);
         rp = view->dev;
-        if (!rp || rp->view != view)
+        if (!rp || rp->view != view ||
+            test_bit(RAW3270_FLAGS_FROZEN, &rp->flags))
                 rc = -EACCES;
         else if (!test_bit(RAW3270_FLAGS_READY, &rp->flags))
                 rc = -ENODEV;
@@ -323,7 +324,8 @@ raw3270_start_locked(struct raw3270_view *view, struct raw3270_request *rq)
         int rc;
 
         rp = view->dev;
-        if (!rp || rp->view != view)
+        if (!rp || rp->view != view ||
+            test_bit(RAW3270_FLAGS_FROZEN, &rp->flags))
                 rc = -EACCES;
         else if (!test_bit(RAW3270_FLAGS_READY, &rp->flags))
                 rc = -ENODEV;
@@ -764,7 +766,8 @@ raw3270_reset(struct raw3270_view *view)
         int rc;
 
         rp = view->dev;
-        if (!rp || rp->view != view)
+        if (!rp || rp->view != view ||
+            test_bit(RAW3270_FLAGS_FROZEN, &rp->flags))
                 rc = -EACCES;
         else if (!test_bit(RAW3270_FLAGS_READY, &rp->flags))
                 rc = -ENODEV;
@@ -922,6 +925,8 @@ raw3270_activate_view(struct raw3270_view *view)
                 rc = 0;
         else if (!test_bit(RAW3270_FLAGS_READY, &rp->flags))
                 rc = -ENODEV;
+        else if (test_bit(RAW3270_FLAGS_FROZEN, &rp->flags))
+                rc = -EACCES;
         else {
                 oldview = NULL;
                 if (rp->view) {
@@ -969,7 +974,8 @@ raw3270_deactivate_view(struct raw3270_view *view)
                 list_del_init(&view->list);
                 list_add_tail(&view->list, &rp->view_list);
                 /* Try to activate another view. */
-                if (test_bit(RAW3270_FLAGS_READY, &rp->flags)) {
+                if (test_bit(RAW3270_FLAGS_READY, &rp->flags) &&
+                    !test_bit(RAW3270_FLAGS_FROZEN, &rp->flags)) {
                         list_for_each_entry(view, &rp->view_list, list) {
                                 rp->view = view;
                                 if (view->fn->activate(view) == 0)
@@ -1068,7 +1074,8 @@ raw3270_del_view(struct raw3270_view *view)
                 rp->view = NULL;
         }
         list_del_init(&view->list);
-        if (!rp->view && test_bit(RAW3270_FLAGS_READY, &rp->flags)) {
+        if (!rp->view && test_bit(RAW3270_FLAGS_READY, &rp->flags) &&
+            !test_bit(RAW3270_FLAGS_FROZEN, &rp->flags)) {
                 /* Try to activate another view. */
                 list_for_each_entry(nv, &rp->view_list, list) {
                         if (nv->fn->activate(nv) == 0) {
@@ -1337,6 +1344,58 @@ raw3270_set_offline (struct ccw_device *cdev)
         return 0;
 }
 
+static int raw3270_pm_stop(struct ccw_device *cdev)
+{
+        struct raw3270 *rp;
+        struct raw3270_view *view;
+        unsigned long flags;
+
+        rp = cdev->dev.driver_data;
+        if (!rp)
+                return 0;
+        spin_lock_irqsave(get_ccwdev_lock(rp->cdev), flags);
+        if (rp->view)
+                rp->view->fn->deactivate(rp->view);
+        if (!test_bit(RAW3270_FLAGS_CONSOLE, &rp->flags)) {
+                /*
+                 * Release tty and fullscreen for all non-console
+                 * devices.
+                 */
+                list_for_each_entry(view, &rp->view_list, list) {
+                        if (view->fn->release)
+                                view->fn->release(view);
+                }
+        }
+        set_bit(RAW3270_FLAGS_FROZEN, &rp->flags);
+        spin_unlock_irqrestore(get_ccwdev_lock(rp->cdev), flags);
+        return 0;
+}
+
+static int raw3270_pm_start(struct ccw_device *cdev)
+{
+        struct raw3270 *rp;
+        unsigned long flags;
+
+        rp = cdev->dev.driver_data;
+        if (!rp)
+                return 0;
+        spin_lock_irqsave(get_ccwdev_lock(rp->cdev), flags);
+        clear_bit(RAW3270_FLAGS_FROZEN, &rp->flags);
+        if (rp->view)
+                rp->view->fn->activate(rp->view);
+        spin_unlock_irqrestore(get_ccwdev_lock(rp->cdev), flags);
+        return 0;
+}
+
+void raw3270_pm_unfreeze(struct raw3270_view *view)
+{
+        struct raw3270 *rp;
+
+        rp = view->dev;
+        if (rp && test_bit(RAW3270_FLAGS_FROZEN, &rp->flags))
+                ccw_device_force_console();
+}
+
 static struct ccw_device_id raw3270_id[] = {
         { CCW_DEVICE(0x3270, 0) },
         { CCW_DEVICE(0x3271, 0) },
@@ -1360,6 +1419,9 @@ static struct ccw_driver raw3270_ccw_driver = {
         .remove         = &raw3270_remove,
         .set_online     = &raw3270_set_online,
         .set_offline    = &raw3270_set_offline,
+        .freeze         = &raw3270_pm_stop,
+        .thaw           = &raw3270_pm_start,
+        .restore        = &raw3270_pm_start,
 };
 
 static int