[PATCH] Corgi Keyboard: Add some power management code

Add some power management code to the corgi keyboard driver so that only one
power event gets reported within any reasonable time frame and the driver
doesn't enter an infinte loop due to key repeat.

Signed-off-by: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

drivers/input/keyboard/corgikbd.c

@@ -16,6 +16,7 @@
 #include <linux/init.h>
 #include <linux/input.h>
 #include <linux/interrupt.h>
+#include <linux/jiffies.h>
 #include <linux/module.h>
 #include <linux/slab.h>
 #include <asm/irq.h>
@@ -78,15 +79,21 @@ struct corgikbd {
 
 	struct timer_list timer;
 	struct timer_list htimer;
+
+	unsigned int suspended;
+	unsigned long suspend_jiffies;
 };
 
 static void handle_scancode(unsigned int pressed,unsigned int scancode, struct corgikbd *corgikbd_data)
 {
 	if (pressed && !(corgikbd_data->state[scancode] & CORGIKBD_PRESSED)) {
 		corgikbd_data->state[scancode] |= CORGIKBD_PRESSED;
 		input_report_key(&corgikbd_data->input, corgikbd_data->keycode[scancode], 1);
-		if (corgikbd_data->keycode[scancode] == CORGI_KEY_OFF)
+		if ((corgikbd_data->keycode[scancode] == CORGI_KEY_OFF)
+				&& time_after(jiffies, corgikbd_data->suspend_jiffies + HZ)) {
 			input_event(&corgikbd_data->input, EV_PWR, CORGI_KEY_OFF, 1);
+			corgikbd_data->suspend_jiffies=jiffies;
+		}
 	} else if (!pressed && corgikbd_data->state[scancode] & CORGIKBD_PRESSED) {
 		corgikbd_data->state[scancode] &= ~CORGIKBD_PRESSED;
 		input_report_key(&corgikbd_data->input, corgikbd_data->keycode[scancode], 0);
@@ -153,6 +160,9 @@ static void corgikbd_scankeyboard(struct corgikbd *corgikbd_data, struct pt_regs
 	unsigned long flags;
 	unsigned int num_pressed;
 
+	if (corgikbd_data->suspended)
+		return;
+
 	spin_lock_irqsave(&corgikbd_data->lock, flags);
 
 	if (regs)
@@ -255,6 +265,32 @@ static void corgikbd_hinge_timer(unsigned long data)
 	mod_timer(&corgikbd_data->htimer, jiffies + HINGE_SCAN_INTERVAL);
 }
 
+#ifdef CONFIG_PM
+static int corgikbd_suspend(struct device *dev, pm_message_t state, uint32_t level)
+{
+	if (level == SUSPEND_POWER_DOWN) {
+		struct corgikbd *corgikbd = dev_get_drvdata(dev);
+		corgikbd->suspended = 1;
+	}
+	return 0;
+}
+
+static int corgikbd_resume(struct device *dev, uint32_t level)
+{
+	if (level == RESUME_POWER_ON) {
+		struct corgikbd *corgikbd = dev_get_drvdata(dev);
+
+		/* Upon resume, ignore the suspend key for a short while */
+		corgikbd->suspend_jiffies=jiffies;
+		corgikbd->suspended = 0;
+	}
+	return 0;
+}
+#else
+#define corgikbd_suspend	NULL
+#define corgikbd_resume		NULL
+#endif
+
 static int __init corgikbd_probe(struct device *dev)
 {
 	int i;
@@ -279,6 +315,8 @@ static int __init corgikbd_probe(struct device *dev)
 	corgikbd->htimer.function = corgikbd_hinge_timer;
 	corgikbd->htimer.data = (unsigned long) corgikbd;
 
+	corgikbd->suspend_jiffies=jiffies;
+
 	init_input_dev(&corgikbd->input);
 	corgikbd->input.private = corgikbd;
 	corgikbd->input.name = "Corgi Keyboard";
@@ -343,6 +381,8 @@ static struct device_driver corgikbd_driver = {
 	.bus		= &platform_bus_type,
 	.probe		= corgikbd_probe,
 	.remove		= corgikbd_remove,
+	.suspend	= corgikbd_suspend,
+	.resume		= corgikbd_resume,
 };
 
 static int __devinit corgikbd_init(void)