iio: hid-sensors: Add API to power on/off

Added an API to allow client drivers to turn ON and OFF sensors for
quick read. Added data_read as counting varaible instead of boolean,
so that sensor is powered off only when last user released it.

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

drivers/iio/accel/hid-sensor-accel-3d.c

@@ -201,9 +201,8 @@ static int accel_3d_proc_event(struct hid_sensor_hub_device *hsdev,
 	struct iio_dev *indio_dev = platform_get_drvdata(priv);
 	struct accel_3d_state *accel_state = iio_priv(indio_dev);
 
-	dev_dbg(&indio_dev->dev, "accel_3d_proc_event [%d]\n",
-				accel_state->common_attributes.data_ready);
-	if (accel_state->common_attributes.data_ready)
+	dev_dbg(&indio_dev->dev, "accel_3d_proc_event\n");
+	if (atomic_read(&accel_state->common_attributes.data_ready))
 		hid_sensor_push_data(indio_dev,
 				accel_state->accel_val,
 				sizeof(accel_state->accel_val));
@@ -342,7 +341,7 @@ static int hid_accel_3d_probe(struct platform_device *pdev)
 		dev_err(&pdev->dev, "failed to initialize trigger buffer\n");
 		goto error_free_dev_mem;
 	}
-	accel_state->common_attributes.data_ready = false;
+	atomic_set(&accel_state->common_attributes.data_ready, 0);
 	ret = hid_sensor_setup_trigger(indio_dev, name,
 					&accel_state->common_attributes);
 	if (ret < 0) {

drivers/iio/common/hid-sensors/hid-sensor-trigger.c

@@ -28,16 +28,17 @@
 #include <linux/iio/sysfs.h>
 #include "hid-sensor-trigger.h"
 
-static int hid_sensor_data_rdy_trigger_set_state(struct iio_trigger *trig,
-						bool state)
+int hid_sensor_power_state(struct hid_sensor_common *st, bool state)
 {
-	struct hid_sensor_common *st = iio_trigger_get_drvdata(trig);
 	int state_val;
 	int report_val;
 
 	if (state) {
 		if (sensor_hub_device_open(st->hsdev))
 			return -EIO;
+
+		atomic_inc(&st->data_ready);
+
 		state_val = hid_sensor_get_usage_index(st->hsdev,
 			st->power_state.report_id,
 			st->power_state.index,
@@ -47,6 +48,8 @@ static int hid_sensor_data_rdy_trigger_set_state(struct iio_trigger *trig,
 			st->report_state.index,
 			HID_USAGE_SENSOR_PROP_REPORTING_STATE_ALL_EVENTS_ENUM);
 	} else {
+		if (!atomic_dec_and_test(&st->data_ready))
+			return 0;
 		sensor_hub_device_close(st->hsdev);
 		state_val = hid_sensor_get_usage_index(st->hsdev,
 			st->power_state.report_id,
@@ -57,7 +60,6 @@ static int hid_sensor_data_rdy_trigger_set_state(struct iio_trigger *trig,
 			st->report_state.index,
 			HID_USAGE_SENSOR_PROP_REPORTING_STATE_NO_EVENTS_ENUM);
 	}
-	st->data_ready = state;
 
 	if (state_val >= 0) {
 		state_val += st->power_state.logical_minimum;
@@ -75,6 +77,13 @@ static int hid_sensor_data_rdy_trigger_set_state(struct iio_trigger *trig,
 
 	return 0;
 }
+EXPORT_SYMBOL(hid_sensor_power_state);
+
+static int hid_sensor_data_rdy_trigger_set_state(struct iio_trigger *trig,
+						bool state)
+{
+	return hid_sensor_power_state(iio_trigger_get_drvdata(trig), state);
+}
 
 void hid_sensor_remove_trigger(struct hid_sensor_common *attrb)
 {

drivers/iio/common/hid-sensors/hid-sensor-trigger.h

@@ -22,5 +22,6 @@
 int hid_sensor_setup_trigger(struct iio_dev *indio_dev, const char *name,
 				struct hid_sensor_common *attrb);
 void hid_sensor_remove_trigger(struct hid_sensor_common *attrb);
+int hid_sensor_power_state(struct hid_sensor_common *st, bool state);
 
 #endif

drivers/iio/gyro/hid-sensor-gyro-3d.c

@@ -201,9 +201,8 @@ static int gyro_3d_proc_event(struct hid_sensor_hub_device *hsdev,
 	struct iio_dev *indio_dev = platform_get_drvdata(priv);
 	struct gyro_3d_state *gyro_state = iio_priv(indio_dev);
 
-	dev_dbg(&indio_dev->dev, "gyro_3d_proc_event [%d]\n",
-				gyro_state->common_attributes.data_ready);
-	if (gyro_state->common_attributes.data_ready)
+	dev_dbg(&indio_dev->dev, "gyro_3d_proc_event\n");
+	if (atomic_read(&gyro_state->common_attributes.data_ready))
 		hid_sensor_push_data(indio_dev,
 				gyro_state->gyro_val,
 				sizeof(gyro_state->gyro_val));
@@ -339,7 +338,7 @@ static int hid_gyro_3d_probe(struct platform_device *pdev)
 		dev_err(&pdev->dev, "failed to initialize trigger buffer\n");
 		goto error_free_dev_mem;
 	}
-	gyro_state->common_attributes.data_ready = false;
+	atomic_set(&gyro_state->common_attributes.data_ready, 0);
 	ret = hid_sensor_setup_trigger(indio_dev, name,
 					&gyro_state->common_attributes);
 	if (ret < 0) {

drivers/iio/light/hid-sensor-als.c

@@ -180,9 +180,8 @@ static int als_proc_event(struct hid_sensor_hub_device *hsdev,
 	struct iio_dev *indio_dev = platform_get_drvdata(priv);
 	struct als_state *als_state = iio_priv(indio_dev);
 
-	dev_dbg(&indio_dev->dev, "als_proc_event [%d]\n",
-				als_state->common_attributes.data_ready);
-	if (als_state->common_attributes.data_ready)
+	dev_dbg(&indio_dev->dev, "als_proc_event\n");
+	if (atomic_read(&als_state->common_attributes.data_ready))
 		hid_sensor_push_data(indio_dev,
 				&als_state->illum,
 				sizeof(als_state->illum));
@@ -305,7 +304,7 @@ static int hid_als_probe(struct platform_device *pdev)
 		dev_err(&pdev->dev, "failed to initialize trigger buffer\n");
 		goto error_free_dev_mem;
 	}
-	als_state->common_attributes.data_ready = false;
+	atomic_set(&als_state->common_attributes.data_ready, 0);
 	ret = hid_sensor_setup_trigger(indio_dev, name,
 				&als_state->common_attributes);
 	if (ret < 0) {

drivers/iio/light/hid-sensor-prox.c

@@ -176,9 +176,8 @@ static int prox_proc_event(struct hid_sensor_hub_device *hsdev,
 	struct iio_dev *indio_dev = platform_get_drvdata(priv);
 	struct prox_state *prox_state = iio_priv(indio_dev);
 
-	dev_dbg(&indio_dev->dev, "prox_proc_event [%d]\n",
-				prox_state->common_attributes.data_ready);
-	if (prox_state->common_attributes.data_ready)
+	dev_dbg(&indio_dev->dev, "prox_proc_event\n");
+	if (atomic_read(&prox_state->common_attributes.data_ready))
 		hid_sensor_push_data(indio_dev,
 				&prox_state->human_presence,
 				sizeof(prox_state->human_presence));
@@ -297,7 +296,7 @@ static int hid_prox_probe(struct platform_device *pdev)
 		dev_err(&pdev->dev, "failed to initialize trigger buffer\n");
 		goto error_free_dev_mem;
 	}
-	prox_state->common_attributes.data_ready = false;
+	atomic_set(&prox_state->common_attributes.data_ready, 0);
 	ret = hid_sensor_setup_trigger(indio_dev, name,
 				&prox_state->common_attributes);
 	if (ret) {

drivers/iio/magnetometer/hid-sensor-magn-3d.c

@@ -202,9 +202,8 @@ static int magn_3d_proc_event(struct hid_sensor_hub_device *hsdev,
 	struct iio_dev *indio_dev = platform_get_drvdata(priv);
 	struct magn_3d_state *magn_state = iio_priv(indio_dev);
 
-	dev_dbg(&indio_dev->dev, "magn_3d_proc_event [%d]\n",
-				magn_state->common_attributes.data_ready);
-	if (magn_state->common_attributes.data_ready)
+	dev_dbg(&indio_dev->dev, "magn_3d_proc_event\n");
+	if (atomic_read(&magn_state->common_attributes.data_ready))
 		hid_sensor_push_data(indio_dev,
 				magn_state->magn_val,
 				sizeof(magn_state->magn_val));
@@ -343,7 +342,7 @@ static int hid_magn_3d_probe(struct platform_device *pdev)
 		dev_err(&pdev->dev, "failed to initialize trigger buffer\n");
 		goto error_free_dev_mem;
 	}
-	magn_state->common_attributes.data_ready = false;
+	atomic_set(&magn_state->common_attributes.data_ready, 0);
 	ret = hid_sensor_setup_trigger(indio_dev, name,
 					&magn_state->common_attributes);
 	if (ret < 0) {

drivers/iio/orientation/hid-sensor-incl-3d.c

@@ -200,9 +200,8 @@ static int incl_3d_proc_event(struct hid_sensor_hub_device *hsdev,
 	struct iio_dev *indio_dev = platform_get_drvdata(priv);
 	struct incl_3d_state *incl_state = iio_priv(indio_dev);
 
-	dev_dbg(&indio_dev->dev, "incl_3d_proc_event [%d]\n",
-				incl_state->common_attributes.data_ready);
-	if (incl_state->common_attributes.data_ready)
+	dev_dbg(&indio_dev->dev, "incl_3d_proc_event\n");
+	if (atomic_read(&incl_state->common_attributes.data_ready))
 		hid_sensor_push_data(indio_dev,
 				(u8 *)incl_state->incl_val,
 				sizeof(incl_state->incl_val));
@@ -358,7 +357,7 @@ static int hid_incl_3d_probe(struct platform_device *pdev)
 		dev_err(&pdev->dev, "failed to initialize trigger buffer\n");
 		goto error_free_dev_mem;
 	}
-	incl_state->common_attributes.data_ready = false;
+	atomic_set(&incl_state->common_attributes.data_ready, 0);
 	ret = hid_sensor_setup_trigger(indio_dev, name,
 					&incl_state->common_attributes);
 	if (ret) {

drivers/iio/orientation/hid-sensor-rotation.c

@@ -145,10 +145,8 @@ static int dev_rot_proc_event(struct hid_sensor_hub_device *hsdev,
 	struct iio_dev *indio_dev = platform_get_drvdata(priv);
 	struct dev_rot_state *rot_state = iio_priv(indio_dev);
 
-	dev_dbg(&indio_dev->dev, "dev_rot_proc_event [%d]\n",
-				rot_state->common_attributes.data_ready);
-
-	if (rot_state->common_attributes.data_ready)
+	dev_dbg(&indio_dev->dev, "dev_rot_proc_event\n");
+	if (atomic_read(&rot_state->common_attributes.data_ready))
 		hid_sensor_push_data(indio_dev,
 				(u8 *)rot_state->sampled_vals,
 				sizeof(rot_state->sampled_vals));
@@ -272,7 +270,7 @@ static int hid_dev_rot_probe(struct platform_device *pdev)
 		dev_err(&pdev->dev, "failed to initialize trigger buffer\n");
 		return ret;
 	}
-	rot_state->common_attributes.data_ready = false;
+	atomic_set(&rot_state->common_attributes.data_ready, 0);
 	ret = hid_sensor_setup_trigger(indio_dev, name,
 					&rot_state->common_attributes);
 	if (ret) {

drivers/iio/pressure/hid-sensor-press.c

@@ -180,9 +180,8 @@ static int press_proc_event(struct hid_sensor_hub_device *hsdev,
 	struct iio_dev *indio_dev = platform_get_drvdata(priv);
 	struct press_state *press_state = iio_priv(indio_dev);
 
-	dev_dbg(&indio_dev->dev, "press_proc_event [%d]\n",
-				press_state->common_attributes.data_ready);
-	if (press_state->common_attributes.data_ready)
+	dev_dbg(&indio_dev->dev, "press_proc_event\n");
+	if (atomic_read(&press_state->common_attributes.data_ready))
 		hid_sensor_push_data(indio_dev,
 				&press_state->press_data,
 				sizeof(press_state->press_data));
@@ -307,7 +306,7 @@ static int hid_press_probe(struct platform_device *pdev)
 		dev_err(&pdev->dev, "failed to initialize trigger buffer\n");
 		goto error_free_dev_mem;
 	}
-	press_state->common_attributes.data_ready = false;
+	atomic_set(&press_state->common_attributes.data_ready, 0);
 	ret = hid_sensor_setup_trigger(indio_dev, name,
 				&press_state->common_attributes);
 	if (ret) {

include/linux/hid-sensor-hub.h

@@ -189,7 +189,7 @@ struct hid_sensor_common {
 	struct hid_sensor_hub_device *hsdev;
 	struct platform_device *pdev;
 	unsigned usage_id;
-	bool data_ready;
+	atomic_t data_ready;
 	struct iio_trigger *trigger;
 	struct hid_sensor_hub_attribute_info poll;
 	struct hid_sensor_hub_attribute_info report_state;