Digi del-5.6 Complete2.6.31-digi-201102151558

1 files changed, 20 insertions, 7 deletions

diff --git a/arch/x86/kernel/i8253.c b/arch/x86/kernel/i8253.c
index 5cf36c053ac4..da890f03d078 100644
--- a/arch/x86/kernel/i8253.c
+++ b/arch/x86/kernel/i8253.c
@@ -21,8 +21,10 @@ EXPORT_SYMBOL(i8253_lock);
 
 #ifdef CONFIG_X86_32
 static void pit_disable_clocksource(void);
+static void pit_enable_clocksource(void);
 #else
 static inline void pit_disable_clocksource(void) { }
+static inline void pit_enable_clocksource(void) { }
 #endif
 
 /*
@@ -67,7 +69,7 @@ static void init_pit_timer(enum clock_event_mode mode,
 		break;
 
 	case CLOCK_EVT_MODE_RESUME:
-		/* Nothing to do here */
+		pit_enable_clocksource();
 		break;
 	}
 	spin_unlock(&i8253_lock);
@@ -200,19 +202,27 @@ static struct clocksource pit_cs = {
 	.shift		= 20,
 };
 
+int pit_cs_registered;
 static void pit_disable_clocksource(void)
 {
-	/*
-	 * Use mult to check whether it is registered or not
-	 */
-	if (pit_cs.mult) {
+	if (pit_cs_registered) {
 		clocksource_unregister(&pit_cs);
-		pit_cs.mult = 0;
+		pit_cs_registered = 0;
+	}
+}
+
+static void pit_enable_clocksource(void)
+{
+	if (!pit_cs_registered && !clocksource_register(&pit_cs)) {
+		pit_cs_registered = 1;
 	}
 }
 
+
+
 static int __init init_pit_clocksource(void)
 {
+	int ret;
 	 /*
 	  * Several reasons not to register PIT as a clocksource:
 	  *
@@ -226,7 +236,10 @@ static int __init init_pit_clocksource(void)
 
 	pit_cs.mult = clocksource_hz2mult(CLOCK_TICK_RATE, pit_cs.shift);
 
-	return clocksource_register(&pit_cs);
+	ret = clocksource_register(&pit_cs);
+	if (!ret)
+		pit_cs_registered = 1;
+	return ret;
 }
 arch_initcall(init_pit_clocksource);