iio: hid-sensors: use asynchronous resume

Some platforms power off sensor hubs during S3 suspend, which will require
longer time to resume. This hurts system resume time, so resume
asynchronously.

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
diff --git a/drivers/iio/common/hid-sensors/hid-sensor-trigger.c b/drivers/iio/common/hid-sensors/hid-sensor-trigger.c
index 5b41f9d..5264ed6 100644
--- a/drivers/iio/common/hid-sensors/hid-sensor-trigger.c
+++ b/drivers/iio/common/hid-sensors/hid-sensor-trigger.c
@@ -122,6 +122,14 @@
 #endif
 }
 
+static void hid_sensor_set_power_work(struct work_struct *work)
+{
+	struct hid_sensor_common *attrb = container_of(work,
+						       struct hid_sensor_common,
+						       work);
+	_hid_sensor_power_state(attrb, true);
+}
+
 static int hid_sensor_data_rdy_trigger_set_state(struct iio_trigger *trig,
 						bool state)
 {
@@ -130,6 +138,7 @@
 
 void hid_sensor_remove_trigger(struct hid_sensor_common *attrb)
 {
+	cancel_work_sync(&attrb->work);
 	iio_trigger_unregister(attrb->trigger);
 	iio_trigger_free(attrb->trigger);
 }
@@ -170,6 +179,9 @@
 		goto error_unreg_trigger;
 
 	iio_device_set_drvdata(indio_dev, attrb);
+
+	INIT_WORK(&attrb->work, hid_sensor_set_power_work);
+
 	pm_suspend_ignore_children(&attrb->pdev->dev, true);
 	pm_runtime_enable(&attrb->pdev->dev);
 	/* Default to 3 seconds, but can be changed from sysfs */
@@ -202,7 +214,15 @@
 	struct platform_device *pdev = to_platform_device(dev);
 	struct iio_dev *indio_dev = platform_get_drvdata(pdev);
 	struct hid_sensor_common *attrb = iio_device_get_drvdata(indio_dev);
+	schedule_work(&attrb->work);
+	return 0;
+}
 
+static int hid_sensor_runtime_resume(struct device *dev)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct iio_dev *indio_dev = platform_get_drvdata(pdev);
+	struct hid_sensor_common *attrb = iio_device_get_drvdata(indio_dev);
 	return _hid_sensor_power_state(attrb, true);
 }
 
@@ -211,7 +231,7 @@
 const struct dev_pm_ops hid_sensor_pm_ops = {
 	SET_SYSTEM_SLEEP_PM_OPS(hid_sensor_suspend, hid_sensor_resume)
 	SET_RUNTIME_PM_OPS(hid_sensor_suspend,
-			   hid_sensor_resume, NULL)
+			   hid_sensor_runtime_resume, NULL)
 };
 EXPORT_SYMBOL(hid_sensor_pm_ops);