5 files changed, 63 insertions, 24 deletions

diff --git a/arch/arm/mach-at91/pm.c b/arch/arm/mach-at91/pm.c
index 4b120cc36135..a67defd50438 100644
--- a/arch/arm/mach-at91/pm.c
+++ b/arch/arm/mach-at91/pm.c
@@ -52,7 +52,7 @@ static suspend_state_t target_state;
 /*
  * Called after processes are frozen, but before we shutdown devices.
  */
-static int at91_pm_set_target(suspend_state_t state)
+static int at91_pm_begin(suspend_state_t state)
 {
         target_state = state;
         return 0;
@@ -202,11 +202,20 @@ error:
         return 0;
 }
 
+/*
+ * Called right prior to thawing processes.
+ */
+static void at91_pm_end(void)
+{
+        target_state = PM_SUSPEND_ON;
+}
+
 
 static struct platform_suspend_ops at91_pm_ops ={
-        .valid          = at91_pm_valid_state,
-        .set_target     = at91_pm_set_target,
-        .enter          = at91_pm_enter,
+        .valid  = at91_pm_valid_state,
+        .begin  = at91_pm_begin,
+        .enter  = at91_pm_enter,
+        .end    = at91_pm_end,
 };
 
 static int __init at91_pm_init(void)
diff --git a/arch/powerpc/platforms/52xx/lite5200_pm.c b/arch/powerpc/platforms/52xx/lite5200_pm.c
index c0f13e8deb0b..41c7fd91e99e 100644
--- a/arch/powerpc/platforms/52xx/lite5200_pm.c
+++ b/arch/powerpc/platforms/52xx/lite5200_pm.c
@@ -31,7 +31,7 @@ static int lite5200_pm_valid(suspend_state_t state)
         }
 }
 
-static int lite5200_pm_set_target(suspend_state_t state)
+static int lite5200_pm_begin(suspend_state_t state)
 {
         if (lite5200_pm_valid(state)) {
                 lite5200_pm_target_state = state;
@@ -219,12 +219,18 @@ static void lite5200_pm_finish(void)
                 mpc52xx_pm_finish();
 }
 
+static void lite5200_pm_end(void)
+{
+        lite5200_pm_target_state = PM_SUSPEND_ON;
+}
+
 static struct platform_suspend_ops lite5200_pm_ops = {
         .valid          = lite5200_pm_valid,
-        .set_target     = lite5200_pm_set_target,
+        .begin          = lite5200_pm_begin,
         .prepare        = lite5200_pm_prepare,
         .enter          = lite5200_pm_enter,
         .finish         = lite5200_pm_finish,
+        .end            = lite5200_pm_end,
 };
 
 int __init lite5200_pm_init(void)
diff --git a/drivers/acpi/sleep/main.c b/drivers/acpi/sleep/main.c
index 96d23b3cfc4e..e2e4e617952b 100644
--- a/drivers/acpi/sleep/main.c
+++ b/drivers/acpi/sleep/main.c
@@ -63,11 +63,11 @@ static u32 acpi_suspend_states[] = {
 static int init_8259A_after_S1;
 
 /**
- *      acpi_pm_set_target - Set the target system sleep state to the state
+ *      acpi_pm_begin - Set the target system sleep state to the state
  *              associated with given @pm_state, if supported.
  */
 
-static int acpi_pm_set_target(suspend_state_t pm_state)
+static int acpi_pm_begin(suspend_state_t pm_state)
 {
         u32 acpi_state = acpi_suspend_states[pm_state];
         int error = 0;
@@ -164,7 +164,7 @@ static int acpi_pm_enter(suspend_state_t pm_state)
 }
 
 /**
- *      acpi_pm_finish - Finish up suspend sequence.
+ *      acpi_pm_finish - Instruct the platform to leave a sleep state.
  *
  *      This is called after we wake back up (or if entering the sleep state
  *      failed). 
@@ -190,6 +190,19 @@ static void acpi_pm_finish(void)
 #endif
 }
 
+/**
+ *      acpi_pm_end - Finish up suspend sequence.
+ */
+
+static void acpi_pm_end(void)
+{
+        /*
+         * This is necessary in case acpi_pm_finish() is not called during a
+         * failing transition to a sleep state.
+         */
+        acpi_target_sleep_state = ACPI_STATE_S0;
+}
+
 static int acpi_pm_state_valid(suspend_state_t pm_state)
 {
         u32 acpi_state;
@@ -208,10 +221,11 @@ static int acpi_pm_state_valid(suspend_state_t pm_state)
 
 static struct platform_suspend_ops acpi_pm_ops = {
         .valid = acpi_pm_state_valid,
-        .set_target = acpi_pm_set_target,
+        .begin = acpi_pm_begin,
         .prepare = acpi_pm_prepare,
         .enter = acpi_pm_enter,
         .finish = acpi_pm_finish,
+        .end = acpi_pm_end,
 };
 
 /*
diff --git a/include/linux/suspend.h b/include/linux/suspend.h
index 51283e0745b3..a0b1dbb5919f 100644
--- a/include/linux/suspend.h
+++ b/include/linux/suspend.h
@@ -38,18 +38,16 @@ typedef int __bitwise suspend_state_t;
  *      There is the %suspend_valid_only_mem function available that can be
  *      assigned to this if the platform only supports mem sleep.
  *
- * @set_target: Tell the platform which system sleep state is going to be
- *      entered.
- *      @set_target() is executed right prior to suspending devices.  The
- *      information conveyed to the platform code by @set_target() should be
- *      disregarded by the platform as soon as @finish() is executed and if
- *      @prepare() fails.  If @set_target() fails (ie. returns nonzero),
+ * @begin: Initialise a transition to given system sleep state.
+ *      @begin() is executed right prior to suspending devices.  The information
+ *      conveyed to the platform code by @begin() should be disregarded by it as
+ *      soon as @end() is executed.  If @begin() fails (ie. returns nonzero),
  *      @prepare(), @enter() and @finish() will not be called by the PM core.
  *      This callback is optional.  However, if it is implemented, the argument
- *      passed to @enter() is meaningless and should be ignored.
+ *      passed to @enter() is redundant and should be ignored.
  *
  * @prepare: Prepare the platform for entering the system sleep state indicated
- *      by @set_target().
+ *      by @begin().
  *      @prepare() is called right after devices have been suspended (ie. the
  *      appropriate .suspend() method has been executed for each device) and
  *      before the nonboot CPUs are disabled (it is executed with IRQs enabled).
@@ -57,8 +55,8 @@ typedef int __bitwise suspend_state_t;
  *      error code otherwise, in which case the system cannot enter the desired
  *      sleep state (@enter() and @finish() will not be called in that case).
  *
- * @enter: Enter the system sleep state indicated by @set_target() or
- *      represented by the argument if @set_target() is not implemented.
+ * @enter: Enter the system sleep state indicated by @begin() or represented by
+ *      the argument if @begin() is not implemented.
  *      This callback is mandatory.  It returns 0 on success or a negative
  *      error code otherwise, in which case the system cannot enter the desired
  *      sleep state.
@@ -69,13 +67,22 @@ typedef int __bitwise suspend_state_t;
  *      This callback is optional, but should be implemented by the platforms
  *      that implement @prepare().  If implemented, it is always called after
  *      @enter() (even if @enter() fails).
+ *
+ * @end: Called by the PM core right after resuming devices, to indicate to
+ *      the platform that the system has returned to the working state or
+ *      the transition to the sleep state has been aborted.
+ *      This callback is optional, but should be implemented by the platforms
+ *      that implement @begin(), but platforms implementing @begin() should
+ *      also provide a @end() which cleans up transitions aborted before
+ *      @enter().
  */
 struct platform_suspend_ops {
         int (*valid)(suspend_state_t state);
-        int (*set_target)(suspend_state_t state);
+        int (*begin)(suspend_state_t state);
         int (*prepare)(void);
         int (*enter)(suspend_state_t state);
         void (*finish)(void);
+        void (*end)(void);
 };
 
 #ifdef CONFIG_SUSPEND
diff --git a/kernel/power/main.c b/kernel/power/main.c
index 050a6077ea45..d9bba452764b 100644
--- a/kernel/power/main.c
+++ b/kernel/power/main.c
@@ -258,10 +258,10 @@ int suspend_devices_and_enter(suspend_state_t state)
         if (!suspend_ops)
                 return -ENOSYS;
 
-        if (suspend_ops->set_target) {
-                error = suspend_ops->set_target(state);
+        if (suspend_ops->begin) {
+                error = suspend_ops->begin(state);
                 if (error)
-                        return error;
+                        goto Close;
         }
         suspend_console();
         error = device_suspend(PMSG_SUSPEND);
@@ -294,6 +294,9 @@ int suspend_devices_and_enter(suspend_state_t state)
         device_resume();
  Resume_console:
         resume_console();
+ Close:
+        if (suspend_ops->end)
+                suspend_ops->end();
         return error;
 }