media: imx: capture: Add a mechanism to disable control inheritance

Add a parameter to the imx_media_capture_device_init() function to
select between the legacy and MC-centric API. When selecting the
MC-centric API, the video node doesn't inherit controls from subdevs
anymore. All callers are updated to use the legacy API for now,
preserving the existing behaviour.
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Rui Miguel Silva <rmfrfs@gmail.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

drivers/staging/media/imx/imx-ic-prpencvf.c

@@ -1265,7 +1265,7 @@ static int prp_registered(struct v4l2_subdev *sd)
 
 	priv->vdev = imx_media_capture_device_init(ic_priv->ipu_dev,
 						   &ic_priv->sd,
-						   PRPENCVF_SRC_PAD);
+						   PRPENCVF_SRC_PAD, true);
 	if (IS_ERR(priv->vdev))
 		return PTR_ERR(priv->vdev);
 

drivers/staging/media/imx/imx-media-capture.c

@@ -45,6 +45,8 @@ struct capture_priv {
 	spinlock_t q_lock;			/* Protect ready_q */
 
 	struct v4l2_ctrl_handler ctrl_hdlr;	/* Controls inherited from subdevs */
+
+	bool legacy_api;			/* Use the legacy (pre-MC) API */
 };
 
 #define to_capture_priv(v) container_of(v, struct capture_priv, vdev)
@@ -800,7 +802,7 @@ EXPORT_SYMBOL_GPL(imx_media_capture_device_unregister);
 
 struct imx_media_video_dev *
 imx_media_capture_device_init(struct device *dev, struct v4l2_subdev *src_sd,
-			      int pad)
+			      int pad, bool legacy_api)
 {
 	struct capture_priv *priv;
 	struct video_device *vfd;
@@ -814,6 +816,7 @@ imx_media_capture_device_init(struct device *dev, struct v4l2_subdev *src_sd,
 	priv->src_sd = src_sd;
 	priv->src_sd_pad = pad;
 	priv->dev = dev;
+	priv->legacy_api = legacy_api;
 
 	mutex_init(&priv->mutex);
 	INIT_LIST_HEAD(&priv->ready_q);
@@ -868,9 +871,11 @@ imx_media_capture_device_init(struct device *dev, struct v4l2_subdev *src_sd,
 		return ERR_PTR(ret);
 	}
 
-	/* Initialize the control handler. */
-	v4l2_ctrl_handler_init(&priv->ctrl_hdlr, 0);
-	vfd->ctrl_handler = &priv->ctrl_hdlr;
+	if (legacy_api) {
+		/* Initialize the control handler. */
+		v4l2_ctrl_handler_init(&priv->ctrl_hdlr, 0);
+		vfd->ctrl_handler = &priv->ctrl_hdlr;
+	}
 
 	return &priv->vdev;
 }

drivers/staging/media/imx/imx-media-csi.c

@@ -1781,9 +1781,8 @@ static int csi_registered(struct v4l2_subdev *sd)
 		goto put_csi;
 	}
 
-	priv->vdev = imx_media_capture_device_init(priv->sd.dev,
-						   &priv->sd,
-						   CSI_SRC_PAD_IDMAC);
+	priv->vdev = imx_media_capture_device_init(priv->sd.dev, &priv->sd,
+						   CSI_SRC_PAD_IDMAC, true);
 	if (IS_ERR(priv->vdev)) {
 		ret = PTR_ERR(priv->vdev);
 		goto free_fim;

drivers/staging/media/imx/imx-media-dev-common.c

@@ -287,6 +287,8 @@ static int imx_media_link_notify(struct media_link *link, u32 flags,
 	    !(flags & MEDIA_LNK_FL_ENABLED)) {
 		list_for_each_entry(pad_vdev, pad_vdev_list, list) {
 			vfd = pad_vdev->vdev->vfd;
+			if (!vfd->ctrl_handler)
+				continue;
 			dev_dbg(imxmd->md.dev,
 				"reset controls for %s\n",
 				vfd->entity.name);
@@ -297,6 +299,8 @@ static int imx_media_link_notify(struct media_link *link, u32 flags,
 		   (link->flags & MEDIA_LNK_FL_ENABLED)) {
 		list_for_each_entry(pad_vdev, pad_vdev_list, list) {
 			vfd = pad_vdev->vdev->vfd;
+			if (!vfd->ctrl_handler)
+				continue;
 			dev_dbg(imxmd->md.dev,
 				"refresh controls for %s\n",
 				vfd->entity.name);

drivers/staging/media/imx/imx-media.h

@@ -286,7 +286,7 @@ int imx_media_ic_unregister(struct v4l2_subdev *sd);
 /* imx-media-capture.c */
 struct imx_media_video_dev *
 imx_media_capture_device_init(struct device *dev, struct v4l2_subdev *src_sd,
-			      int pad);
+			      int pad, bool legacy_api);
 void imx_media_capture_device_remove(struct imx_media_video_dev *vdev);
 int imx_media_capture_device_register(struct imx_media_video_dev *vdev);
 void imx_media_capture_device_unregister(struct imx_media_video_dev *vdev);

drivers/staging/media/imx/imx7-media-csi.c

@@ -1100,7 +1100,7 @@ static int imx7_csi_registered(struct v4l2_subdev *sd)
 	}
 
 	csi->vdev = imx_media_capture_device_init(csi->sd.dev, &csi->sd,
-						  IMX7_CSI_PAD_SRC);
+						  IMX7_CSI_PAD_SRC, true);
 	if (IS_ERR(csi->vdev))
 		return PTR_ERR(csi->vdev);