PM: Improve error code of pm_notifier_call_chain()

This enables pm_notifier_call_chain() to get the actual error code
in the callback rather than always assume -EINVAL by converting all
PM notifier calls to return encapsulate error code with
notifier_from_errno().

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>

4 files changed, 10 insertions, 9 deletions

diff --git a/drivers/char/apm-emulation.c b/drivers/char/apm-emulation.c
index 548708c4b2b8..a7346ab97a3c 100644
--- a/drivers/char/apm-emulation.c
+++ b/drivers/char/apm-emulation.c
@@ -606,7 +606,7 @@ static int apm_suspend_notifier(struct notifier_block *nb,
                         return NOTIFY_OK;
 
                 /* interrupted by signal */
-                return NOTIFY_BAD;
+                return notifier_from_errno(err);
 
         case PM_POST_SUSPEND:
                 /*
diff --git a/drivers/s390/char/vmwatchdog.c b/drivers/s390/char/vmwatchdog.c
index 12ef9121d4f0..11312f401c70 100644
--- a/drivers/s390/char/vmwatchdog.c
+++ b/drivers/s390/char/vmwatchdog.c
@@ -258,13 +258,13 @@ static int vmwdt_suspend(void)
         if (test_and_set_bit(VMWDT_OPEN, &vmwdt_is_open)) {
                 pr_err("The system cannot be suspended while the watchdog"
                         " is in use\n");
-                return NOTIFY_BAD;
+                return notifier_from_errno(-EBUSY);
         }
         if (test_bit(VMWDT_RUNNING, &vmwdt_is_open)) {
                 clear_bit(VMWDT_OPEN, &vmwdt_is_open);
                 pr_err("The system cannot be suspended while the watchdog"
                         " is running\n");
-                return NOTIFY_BAD;
+                return notifier_from_errno(-EBUSY);
         }
         return NOTIFY_DONE;
 }
diff --git a/drivers/s390/cio/css.c b/drivers/s390/cio/css.c
index c47b25fd3f43..92d7324acb1c 100644
--- a/drivers/s390/cio/css.c
+++ b/drivers/s390/cio/css.c
@@ -814,8 +814,8 @@ static int css_power_event(struct notifier_block *this, unsigned long event,
                                 mutex_unlock(&css->mutex);
                                 continue;
                         }
-                        if (__chsc_do_secm(css, 0))
-                                ret = NOTIFY_BAD;
+                        ret = __chsc_do_secm(css, 0);
+                        ret = notifier_from_errno(ret);
                         mutex_unlock(&css->mutex);
                 }
                 break;
@@ -831,8 +831,8 @@ static int css_power_event(struct notifier_block *this, unsigned long event,
                                 mutex_unlock(&css->mutex);
                                 continue;
                         }
-                        if (__chsc_do_secm(css, 1))
-                                ret = NOTIFY_BAD;
+                        ret = __chsc_do_secm(css, 1);
+                        ret = notifier_from_errno(ret);
                         mutex_unlock(&css->mutex);
                 }
                 /* search for subchannels, which appeared during hibernation */
diff --git a/kernel/power/main.c b/kernel/power/main.c
index 2981af4ce7cb..6c601f871964 100644
--- a/kernel/power/main.c
+++ b/kernel/power/main.c
@@ -37,8 +37,9 @@ EXPORT_SYMBOL_GPL(unregister_pm_notifier);
 
 int pm_notifier_call_chain(unsigned long val)
 {
-        return (blocking_notifier_call_chain(&pm_chain_head, val, NULL)
-                        == NOTIFY_BAD) ? -EINVAL : 0;
+        int ret = blocking_notifier_call_chain(&pm_chain_head, val, NULL);
+
+        return notifier_to_errno(ret);
 }
 
 /* If set, devices may be suspended and resumed asynchronously. */