media: sun6i-csi: Add support for hooking to the isp devices

In order to use the isp and csi together, both devices need to be
parented to the same v4l2 and media devices. We use the isp as
top-level device and let the csi code hook to its v4l2 and media
devices when async subdev registration takes place.

As a result v4l2/media device setup is only called when the ISP
is missing and the capture device is registered after the devices
are hooked. The bridge subdev and its notifier are registered
without any device when the ISP is available. Top-level pointers
for the devices are introduced to either redirect to the hooked ones
(isp available) or the registered ones (isp missing).

Also keep track of whether the capture node was setup or not to
avoid cleaning up resources when it wasn't.

Signed-off-by: Paul Kocialkowski <paul.kocialkowski@bootlin.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

1 files changed, 37 insertions, 8 deletions

diff --git a/drivers/media/platform/sunxi/sun6i-csi/sun6i_csi.c b/drivers/media/platform/sunxi/sun6i-csi/sun6i_csi.c
index 0513b7b0c2a0..e3e6650181c8 100644
--- a/drivers/media/platform/sunxi/sun6i-csi/sun6i_csi.c
+++ b/drivers/media/platform/sunxi/sun6i-csi/sun6i_csi.c
@@ -26,6 +26,18 @@
 
 /* ISP */
 
+int sun6i_csi_isp_complete(struct sun6i_csi_device *csi_dev,
+			   struct v4l2_device *v4l2_dev)
+{
+	if (csi_dev->v4l2_dev && csi_dev->v4l2_dev != v4l2_dev)
+		return -EINVAL;
+
+	csi_dev->v4l2_dev = v4l2_dev;
+	csi_dev->media_dev = v4l2_dev->mdev;
+
+	return sun6i_csi_capture_setup(csi_dev);
+}
+
 static int sun6i_csi_isp_detect(struct sun6i_csi_device *csi_dev)
 {
 	struct device *dev = csi_dev->dev;
@@ -96,6 +108,9 @@ static int sun6i_csi_v4l2_setup(struct sun6i_csi_device *csi_dev)
 		goto error_media;
 	}
 
+	csi_dev->v4l2_dev = v4l2_dev;
+	csi_dev->media_dev = media_dev;
+
 	return 0;
 
 error_media:
@@ -323,17 +338,27 @@ static int sun6i_csi_probe(struct platform_device *platform_dev)
 	if (ret)
 		goto error_resources;
 
-	ret = sun6i_csi_v4l2_setup(csi_dev);
-	if (ret)
-		goto error_resources;
+	/*
+	 * Register our own v4l2 and media devices when there is no ISP around.
+	 * Otherwise the ISP will use async subdev registration with our bridge,
+	 * which will provide v4l2 and media devices that are used to register
+	 * the video interface.
+	 */
+	if (!csi_dev->isp_available) {
+		ret = sun6i_csi_v4l2_setup(csi_dev);
+		if (ret)
+			goto error_resources;
+	}
 
 	ret = sun6i_csi_bridge_setup(csi_dev);
 	if (ret)
 		goto error_v4l2;
 
-	ret = sun6i_csi_capture_setup(csi_dev);
-	if (ret)
-		goto error_bridge;
+	if (!csi_dev->isp_available) {
+		ret = sun6i_csi_capture_setup(csi_dev);
+		if (ret)
+			goto error_bridge;
+	}
 
 	return 0;
 
@@ -341,7 +366,8 @@ error_bridge:
 	sun6i_csi_bridge_cleanup(csi_dev);
 
 error_v4l2:
-	sun6i_csi_v4l2_cleanup(csi_dev);
+	if (!csi_dev->isp_available)
+		sun6i_csi_v4l2_cleanup(csi_dev);
 
 error_resources:
 	sun6i_csi_resources_cleanup(csi_dev);
@@ -355,7 +381,10 @@ static int sun6i_csi_remove(struct platform_device *pdev)
 
 	sun6i_csi_capture_cleanup(csi_dev);
 	sun6i_csi_bridge_cleanup(csi_dev);
-	sun6i_csi_v4l2_cleanup(csi_dev);
+
+	if (!csi_dev->isp_available)
+		sun6i_csi_v4l2_cleanup(csi_dev);
+
 	sun6i_csi_resources_cleanup(csi_dev);
 
 	return 0;