Hold wakelock while there are active power key related timers

There is a state machine for separating short, long and double
power key presses. The detection logic uses timers, and we need
to ensure the device does not fall back to suspend while the
timers are active.

[mce] Hold wakelock while there are active power key related timers

.depend

@@ -687,6 +687,7 @@ modules/radiostates.pic.o:\
 powerkey.o:\
 	powerkey.c\
 	datapipe.h\
+	libwakelock.h\
 	mce-conf.h\
 	mce-dbus.h\
 	mce-dsme.h\
@@ -697,6 +698,7 @@ powerkey.o:\
 powerkey.pic.o:\
 	powerkey.c\
 	datapipe.h\
+	libwakelock.h\
 	mce-conf.h\
 	mce-dbus.h\
 	mce-dsme.h\

mce.c

@@ -288,6 +288,7 @@ static void mce_cleanup_wakelocks(void)
 	wakelock_unlock("mce_input_handler");
 	wakelock_unlock("mce_cpu_keepalive");
 	wakelock_unlock("mce_display_stm");
+	wakelock_unlock("mce_powerkey_stm");
 }
 #endif // ENABLE_WAKELOCKS
 

powerkey.c

@@ -73,6 +73,10 @@
 					 * remove_input_trigger_from_datapipe()
 					 */
 
+#ifdef ENABLE_WAKELOCKS
+# include "libwakelock.h"
+#endif
+
 #if 0 // DEBUG: make all logging from this module "critical"
 # undef mce_log
 # define mce_log(LEV, FMT, ARGS...) \
@@ -113,6 +117,43 @@ static gchar *doublepresssignal = NULL;
 
 static void cancel_powerkey_timeout(void);
 
+/** Check if we need to hold a wakelock for power key handling
+ *
+ * Effectively wakelock can be acquired only due to power key
+ * pressed handling in powerkey_trigger().
+ *
+ * Releasing wakelock happens after power key is released
+ * and/or long/double tap timeouts get triggered.
+ *
+ * Timer re-programming does not affect wakelock status on purpose.
+ */
+static void powerkey_wakelock_rethink(void)
+{
+#ifdef ENABLE_WAKELOCKS
+	static bool have_lock = false;
+
+	bool want_lock = false;
+
+	/* hold wakelock while we have active power key timers */
+	if( powerkey_timeout_cb_id || doublepress_timeout_cb_id ) {
+		want_lock = true;
+	}
+	if( have_lock == want_lock )
+		goto EXIT;
+
+	if( (have_lock = want_lock) ) {
+		wakelock_lock("mce_powerkey_stm", -1);
+		mce_log(LL_DEBUG, "acquire wakelock");
+	}
+	else {
+		mce_log(LL_DEBUG, "release wakelock");
+		wakelock_unlock("mce_powerkey_stm");
+	}
+EXIT:
+	return;
+#endif
+}
+
 /**
  * Generic logic for key presses
  *
@@ -263,6 +304,9 @@ static gboolean doublepress_timeout_cb(gpointer data)
 		generic_powerkey_handler(shortpressaction,
 					 shortpresssignal);
 
+	/* Release wakelock if all timers are inactive */
+	powerkey_wakelock_rethink();
+
 	return FALSE;
 }
 
@@ -415,6 +459,9 @@ static gboolean powerkey_timeout_cb(gpointer data)
 
 	handle_longpress();
 
+	/* Release wakelock if all timers are inactive */
+	powerkey_wakelock_rethink();
+
 	return FALSE;
 }
 
@@ -596,6 +643,10 @@ static void powerkey_trigger(gconstpointer const data)
 				handle_shortpress();
 			}
 		}
+
+		/* Acquire/release a wakelock depending on whether
+		 * there are active powerkey timers or not */
+		powerkey_wakelock_rethink();
 	}
 
 EXIT:
@@ -742,5 +793,8 @@ void mce_powerkey_exit(void)
 	g_free(longpresssignal);
 	g_free(shortpresssignal);
 
+	/* Release wakelock */
+	powerkey_wakelock_rethink();
+
 	return;
 }