[PATCH] driver model wakeup flags

This is a refresh of an earlier patch to add "wakeup" support to the
PM core model.  This provides per-device bus-neutral control of the
use of wakeup events.

  * "struct device_pm_info" has two bits that are initialized as
    part of setting up the enclosing struct device:
      - "can_wakeup", reflecting hardware capabilities
      - "may_wakeup", the policy setting (when CONFIG_PM)

  * There's a writeable sysfs "wakeup" file, with one of two values:
      - "enabled", when the policy is to allow wakeup
      - "disabled", when the policy is not to allow it
      - "" if the device can't currently issue wakeups

By default, wakeup is enabled on all devices that support it.  If its
driver doesn't support it ... treat it as a bug.  :)

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 25 insertions, 1 deletions

diff --git a/include/linux/pm.h b/include/linux/pm.h
index 5cfb07648ec..7897cf500c5 100644
--- a/include/linux/pm.h
+++ b/include/linux/pm.h
@@ -219,7 +219,9 @@ typedef struct pm_message {
 
 struct dev_pm_info {
         pm_message_t            power_state;
+        unsigned                can_wakeup:1;
 #ifdef  CONFIG_PM
+        unsigned                should_wakeup:1;
         pm_message_t            prev_state;
         void                    * saved_state;
         atomic_t                pm_users;
@@ -236,13 +238,35 @@ extern void device_resume(void);
 
 #ifdef CONFIG_PM
 extern int device_suspend(pm_message_t state);
-#else
+
+#define device_set_wakeup_enable(dev,val) \
+        ((dev)->power.should_wakeup = !!(val))
+#define device_may_wakeup(dev) \
+        (device_can_wakeup(dev) && (dev)->power.should_wakeup)
+
+#else /* !CONFIG_PM */
+
 static inline int device_suspend(pm_message_t state)
 {
         return 0;
 }
+
+#define device_set_wakeup_enable(dev,val)       do{}while(0)
+#define device_may_wakeup(dev)                  (0)
+
 #endif
 
+/* changes to device_may_wakeup take effect on the next pm state change.
+ * by default, devices should wakeup if they can.
+ */
+#define device_can_wakeup(dev) \
+        ((dev)->power.can_wakeup)
+#define device_init_wakeup(dev,val) \
+        do { \
+                device_can_wakeup(dev) = !!(val); \
+                device_set_wakeup_enable(dev,val); \
+        } while(0)
+
 #endif /* __KERNEL__ */
 
 #endif /* _LINUX_PM_H */