[PATCH 11/12] hdaps: Stop polling timer when suspended

[Shem Multinymous <multinymous@gmail.com>]

This patch stops the hdaps driver's polling timer when the module is 
suspended. Accessing a shut-down accelerometer is not harmful, but 
let's avoid it anyway.

Signed-off-by: Shem Multinymous <multinymous@gmail.com>
Signed-off-by: Pavel Machek <pavel@suse.cz>
---
 drivers/hwmon/hdaps.c |   17 +++++++++++------
 1 file changed, 11 insertions(+), 6 deletions(-)

--- a/drivers/hwmon/hdaps.c
+++ b/drivers/hwmon/hdaps.c
@@ -407,13 +407,19 @@ static int hdaps_probe(struct platform_d
 
 static int hdaps_suspend(struct platform_device *dev, pm_message_t state)
 {
+	/* Don't do hdaps polls until resume re-initializes the sensor. */
+	del_timer_sync(&hdaps_timer);
 	hdaps_device_shutdown(); /* ignore errors, effect is negligible */
 	return 0;
 }
 
 static int hdaps_resume(struct platform_device *dev)
 {
-	return hdaps_device_init();
+	int ret = hdaps_device_init();
+	if (ret)
+		return ret;
+	mod_timer(&hdaps_timer, jiffies + HZ/sampling_rate);
+	return 0;
 }
 
 static struct platform_driver hdaps_driver = {
@@ -751,6 +757,9 @@ static int __init hdaps_init(void)
 		goto out;
 	}
 
+	/* Init timer before platform_driver_register, in case of suspend */
+	init_timer(&hdaps_timer);
+	hdaps_timer.function = hdaps_mousedev_poll;
 	ret = platform_driver_register(&hdaps_driver);
 	if (ret)
 		goto out;
@@ -785,11 +794,7 @@ static int __init hdaps_init(void)
 
 	input_register_device(hdaps_idev);
 
-	/* start up our timer for the input device */
-	init_timer(&hdaps_timer);
-	hdaps_timer.function = hdaps_mousedev_poll;
-	hdaps_timer.expires = jiffies + HZ/sampling_rate;
-	add_timer(&hdaps_timer);
+	mod_timer(&hdaps_timer, jiffies + HZ/sampling_rate);
 
 	printk(KERN_INFO "hdaps: driver successfully loaded.\n");
 	return 0;