input: pwrkey: Handle out-of-order press and release interrupts

There is a possibility of receiving a release interrupt
before press when both these actions (press and release) of the
power-key are very close-by (~1-2ms) to the debounce time
of the key. Handle this case by maintaining a state variable.

Also mark the release interrupt as a wakeup source to
wakeup the system when the above mentioned abnormal case
occurs.

CRs-Fixed: 394289
Change-Id: I74475c1e5159dd30e52aca91243eec7e2fac4d57
Signed-off-by: Anirudh Ghayal <aghayal@codeaurora.org>

drivers/input/misc/pmic8xxx-pwrkey.c

-/* Copyright (c) 2010-2011, Code Aurora Forum. All rights reserved.
+/* Copyright (c) 2010-2012, The Linux Foundation. All rights reserved.
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 2 and
@@ -35,6 +35,8 @@
 struct pmic8xxx_pwrkey {
 	struct input_dev *pwr;
 	int key_press_irq;
+	int key_release_irq;
+	bool press;
 	const struct pm8xxx_pwrkey_platform_data *pdata;
 };
 
@@ -42,6 +44,13 @@ static irqreturn_t pwrkey_press_irq(int irq, void *_pwrkey)
 {
 	struct pmic8xxx_pwrkey *pwrkey = _pwrkey;
 
+	if (pwrkey->press == true) {
+		pwrkey->press = false;
+		return IRQ_HANDLED;
+	} else {
+		pwrkey->press = true;
+	}
+
 	input_report_key(pwrkey->pwr, KEY_POWER, 1);
 	input_sync(pwrkey->pwr);
 
@@ -52,6 +61,14 @@ static irqreturn_t pwrkey_release_irq(int irq, void *_pwrkey)
 {
 	struct pmic8xxx_pwrkey *pwrkey = _pwrkey;
 
+	if (pwrkey->press == false) {
+		input_report_key(pwrkey->pwr, KEY_POWER, 1);
+		input_sync(pwrkey->pwr);
+		pwrkey->press = true;
+	} else {
+		pwrkey->press = false;
+	}
+
 	input_report_key(pwrkey->pwr, KEY_POWER, 0);
 	input_sync(pwrkey->pwr);
 
@@ -63,8 +80,10 @@ static int pmic8xxx_pwrkey_suspend(struct device *dev)
 {
 	struct pmic8xxx_pwrkey *pwrkey = dev_get_drvdata(dev);
 
-	if (device_may_wakeup(dev))
+	if (device_may_wakeup(dev)) {
 		enable_irq_wake(pwrkey->key_press_irq);
+		enable_irq_wake(pwrkey->key_release_irq);
+	}
 
 	return 0;
 }
@@ -73,8 +92,10 @@ static int pmic8xxx_pwrkey_resume(struct device *dev)
 {
 	struct pmic8xxx_pwrkey *pwrkey = dev_get_drvdata(dev);
 
-	if (device_may_wakeup(dev))
+	if (device_may_wakeup(dev)) {
 		disable_irq_wake(pwrkey->key_press_irq);
+		disable_irq_wake(pwrkey->key_release_irq);
+	}
 
 	return 0;
 }
@@ -155,7 +176,9 @@ static int __devinit pmic8xxx_pwrkey_probe(struct platform_device *pdev)
 	}
 
 	pwrkey->key_press_irq = key_press_irq;
+	pwrkey->key_release_irq = key_release_irq;
 	pwrkey->pwr = pwr;
+	pwrkey->press = false;
 
 	platform_set_drvdata(pdev, pwrkey);