media: i2c: imx296: Replace streaming flag with runtime PM check

The streaming flag in the driver private structure is used for the sole
purpose of gating register writes when setting a V4L2 control. This is
better handled by checking if the sensor is powered up using the runtime
PM API. Do so and drop the streaming flag.
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Tommaso Merciai <tomm.merciai@gmail.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>

drivers/media/i2c/imx296.c

@@ -201,8 +201,6 @@ struct imx296 {
 	const struct imx296_clk_params *clk_params;
 	bool mono;
 
-	bool streaming;
-
 	struct v4l2_subdev subdev;
 	struct media_pad pad;
 
@@ -321,7 +319,7 @@ static int imx296_s_ctrl(struct v4l2_ctrl *ctrl)
 	unsigned int vmax;
 	int ret = 0;
 
-	if (!sensor->streaming)
+	if (!pm_runtime_get_if_in_use(sensor->dev))
 		return 0;
 
 	state = v4l2_subdev_get_locked_active_state(&sensor->subdev);
@@ -376,6 +374,8 @@ static int imx296_s_ctrl(struct v4l2_ctrl *ctrl)
 		break;
 	}
 
+	pm_runtime_put(sensor->dev);
+
 	return ret;
 }
 
@@ -607,8 +607,6 @@ static int imx296_s_stream(struct v4l2_subdev *sd, int enable)
 		pm_runtime_mark_last_busy(sensor->dev);
 		pm_runtime_put_autosuspend(sensor->dev);
 
-		sensor->streaming = false;
-
 		goto unlock;
 	}
 
@@ -620,13 +618,6 @@ static int imx296_s_stream(struct v4l2_subdev *sd, int enable)
 	if (ret < 0)
 		goto err_pm;
 
-	/*
-	 * Set streaming to true to ensure __v4l2_ctrl_handler_setup() will set
-	 * the controls. The flag is reset to false further down if an error
-	 * occurs.
-	 */
-	sensor->streaming = true;
-
 	ret = __v4l2_ctrl_handler_setup(&sensor->ctrls);
 	if (ret < 0)
 		goto err_pm;
@@ -646,7 +637,6 @@ static int imx296_s_stream(struct v4l2_subdev *sd, int enable)
 	 * likely has no other chance to recover.
 	 */
 	pm_runtime_put_sync(sensor->dev);
-	sensor->streaming = false;
 
 	goto unlock;
 }