diff --git a/drivers/input/keyboard/pxa27x_keypad.c b/drivers/input/keyboard/pxa27x_keypad.c
index 29fe1b2..b07771e 100644
--- a/drivers/input/keyboard/pxa27x_keypad.c
+++ b/drivers/input/keyboard/pxa27x_keypad.c
@@ -399,7 +399,7 @@
 	struct pxa27x_keypad *keypad = input_get_drvdata(dev);
 
 	/* Enable unit clock */
-	clk_enable(keypad->clk);
+	clk_prepare_enable(keypad->clk);
 	pxa27x_keypad_config(keypad);
 
 	return 0;
@@ -410,7 +410,7 @@
 	struct pxa27x_keypad *keypad = input_get_drvdata(dev);
 
 	/* Disable clock unit */
-	clk_disable(keypad->clk);
+	clk_disable_unprepare(keypad->clk);
 }
 
 #ifdef CONFIG_PM
@@ -419,10 +419,14 @@
 	struct platform_device *pdev = to_platform_device(dev);
 	struct pxa27x_keypad *keypad = platform_get_drvdata(pdev);
 
-	clk_disable(keypad->clk);
-
+	/*
+	 * If the keypad is used a wake up source, clock can not be disabled.
+	 * Or it can not detect the key pressing.
+	 */
 	if (device_may_wakeup(&pdev->dev))
 		enable_irq_wake(keypad->irq);
+	else
+		clk_disable_unprepare(keypad->clk);
 
 	return 0;
 }
@@ -433,19 +437,24 @@
 	struct pxa27x_keypad *keypad = platform_get_drvdata(pdev);
 	struct input_dev *input_dev = keypad->input_dev;
 
-	if (device_may_wakeup(&pdev->dev))
+	/*
+	 * If the keypad is used as wake up source, the clock is not turned
+	 * off. So do not need configure it again.
+	 */
+	if (device_may_wakeup(&pdev->dev)) {
 		disable_irq_wake(keypad->irq);
+	} else {
+		mutex_lock(&input_dev->mutex);
 
-	mutex_lock(&input_dev->mutex);
+		if (input_dev->users) {
+			/* Enable unit clock */
+			clk_prepare_enable(keypad->clk);
+			pxa27x_keypad_config(keypad);
+		}
 
-	if (input_dev->users) {
-		/* Enable unit clock */
-		clk_enable(keypad->clk);
-		pxa27x_keypad_config(keypad);
+		mutex_unlock(&input_dev->mutex);
 	}
 
-	mutex_unlock(&input_dev->mutex);
-
 	return 0;
 }