4 files changed, 39 insertions, 26 deletions

diff --git a/drivers/acpi/power.c b/drivers/acpi/power.c
index d74365d4a6e7..5a09bf392ec1 100644
--- a/drivers/acpi/power.c
+++ b/drivers/acpi/power.c
@@ -44,6 +44,8 @@
 #include <acpi/acpi_bus.h>
 #include <acpi/acpi_drivers.h>
 
+#include "sleep.h"
+
 #define _COMPONENT                      ACPI_POWER_COMPONENT
 ACPI_MODULE_NAME("power");
 #define ACPI_POWER_CLASS                "power_resource"
@@ -361,17 +363,15 @@ int acpi_device_sleep_wake(struct acpi_device *dev,
  */
 int acpi_enable_wakeup_device_power(struct acpi_device *dev, int sleep_state)
 {
-        int i, err;
+        int i, err = 0;
 
         if (!dev || !dev->wakeup.flags.valid)
                 return -EINVAL;
 
-        /*
-         * Do not execute the code below twice in a row without calling
-         * acpi_disable_wakeup_device_power() in between for the same device
-         */
-        if (dev->wakeup.flags.prepared)
-                return 0;
+        mutex_lock(&acpi_device_lock);
+
+        if (dev->wakeup.prepare_count++)
+                goto out;
 
         /* Open power resource */
         for (i = 0; i < dev->wakeup.resources.count; i++) {
@@ -379,7 +379,8 @@ int acpi_enable_wakeup_device_power(struct acpi_device *dev, int sleep_state)
                 if (ret) {
                         printk(KERN_ERR PREFIX "Transition power state\n");
                         dev->wakeup.flags.valid = 0;
-                        return -ENODEV;
+                        err = -ENODEV;
+                        goto err_out;
                 }
         }
 
@@ -388,9 +389,13 @@ int acpi_enable_wakeup_device_power(struct acpi_device *dev, int sleep_state)
          * in arbitrary power state afterwards.
          */
         err = acpi_device_sleep_wake(dev, 1, sleep_state, 3);
-        if (!err)
-                dev->wakeup.flags.prepared = 1;
 
+ err_out:
+        if (err)
+                dev->wakeup.prepare_count = 0;
+
+ out:
+        mutex_unlock(&acpi_device_lock);
         return err;
 }
 
@@ -402,35 +407,42 @@ int acpi_enable_wakeup_device_power(struct acpi_device *dev, int sleep_state)
  */
 int acpi_disable_wakeup_device_power(struct acpi_device *dev)
 {
-        int i, ret;
+        int i, err = 0;
 
         if (!dev || !dev->wakeup.flags.valid)
                 return -EINVAL;
 
+        mutex_lock(&acpi_device_lock);
+
+        if (--dev->wakeup.prepare_count > 0)
+                goto out;
+
         /*
-         * Do not execute the code below twice in a row without calling
-         * acpi_enable_wakeup_device_power() in between for the same device
+         * Executing the code below even if prepare_count is already zero when
+         * the function is called may be useful, for example for initialisation.
          */
-        if (!dev->wakeup.flags.prepared)
-                return 0;
+        if (dev->wakeup.prepare_count < 0)
+                dev->wakeup.prepare_count = 0;
 
-        dev->wakeup.flags.prepared = 0;
-
-        ret = acpi_device_sleep_wake(dev, 0, 0, 0);
-        if (ret)
-                return ret;
+        err = acpi_device_sleep_wake(dev, 0, 0, 0);
+        if (err)
+                goto out;
 
         /* Close power resource */
         for (i = 0; i < dev->wakeup.resources.count; i++) {
-                ret = acpi_power_off_device(dev->wakeup.resources.handles[i], dev);
+                int ret = acpi_power_off_device(
+                                dev->wakeup.resources.handles[i], dev);
                 if (ret) {
                         printk(KERN_ERR PREFIX "Transition power state\n");
                         dev->wakeup.flags.valid = 0;
-                        return -ENODEV;
+                        err = -ENODEV;
+                        goto out;
                 }
         }
 
-        return ret;
+ out:
+        mutex_unlock(&acpi_device_lock);
+        return err;
 }
 
 /* --------------------------------------------------------------------------
diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c
index 781435d7e369..318b1ea7a5bf 100644
--- a/drivers/acpi/scan.c
+++ b/drivers/acpi/scan.c
@@ -781,6 +781,7 @@ static int acpi_bus_get_wakeup_device_flags(struct acpi_device *device)
         kfree(buffer.pointer);
 
         device->wakeup.flags.valid = 1;
+        device->wakeup.prepare_count = 0;
         /* Call _PSW/_DSW object to disable its ability to wake the sleeping
          * system for the ACPI device with the _PRW object.
          * The _PSW object is depreciated in ACPI 3.0 and is replaced by _DSW.
diff --git a/drivers/acpi/wakeup.c b/drivers/acpi/wakeup.c
index 88725dcdf8bc..e0ee0c036f5a 100644
--- a/drivers/acpi/wakeup.c
+++ b/drivers/acpi/wakeup.c
@@ -68,7 +68,7 @@ void acpi_enable_wakeup_device(u8 sleep_state)
                 /* If users want to disable run-wake GPE,
                  * we only disable it for wake and leave it for runtime
                  */
-                if ((!dev->wakeup.state.enabled && !dev->wakeup.flags.prepared)
+                if ((!dev->wakeup.state.enabled && !dev->wakeup.prepare_count)
                     || sleep_state > (u32) dev->wakeup.sleep_state) {
                         if (dev->wakeup.flags.run_wake) {
                                 /* set_gpe_type will disable GPE, leave it like that */
@@ -100,7 +100,7 @@ void acpi_disable_wakeup_device(u8 sleep_state)
                 if (!dev->wakeup.flags.valid)
                         continue;
 
-                if ((!dev->wakeup.state.enabled && !dev->wakeup.flags.prepared)
+                if ((!dev->wakeup.state.enabled && !dev->wakeup.prepare_count)
                     || sleep_state > (u32) dev->wakeup.sleep_state) {
                         if (dev->wakeup.flags.run_wake) {
                                 acpi_set_gpe_type(dev->wakeup.gpe_device,
diff --git a/include/acpi/acpi_bus.h b/include/acpi/acpi_bus.h
index c3ace75d57b4..1fa3ffb7c93b 100644
--- a/include/acpi/acpi_bus.h
+++ b/include/acpi/acpi_bus.h
@@ -248,7 +248,6 @@ struct acpi_device_perf {
 /* Wakeup Management */
 struct acpi_device_wakeup_flags {
         u8 valid:1;             /* Can successfully enable wakeup? */
-        u8 prepared:1;          /* Has the wake-up capability been enabled? */
         u8 run_wake:1;          /* Run-Wake GPE devices */
 };
 
@@ -263,6 +262,7 @@ struct acpi_device_wakeup {
         struct acpi_handle_list resources;
         struct acpi_device_wakeup_state state;
         struct acpi_device_wakeup_flags flags;
+        int prepare_count;
 };
 
 /* Device */