Add initial support for media controller framework to the renesas-ceu driver.
Adding media-controller support allows to operate sensors that expose advanced
functionalities through the v4l2-subdev APIs.
Signed-off-by: Jacopo Mondi <jacopo+renesas@xxxxxxxxxx>
---
Hello,
I'm in the process of adding support to a sensor driver that exposes advanced
functionalities through the v4l2-subdev APIs.
In order to operate on it, I had to add initial media-controller support to the
host driver (renesas-ceu) to have the subdevice video nodes properly created.
The current implementation allows to create and operate on the media graph, but
the result is a lot of #ifdef in the driver code I don't see in any other
mainline platform driver.
As there are more media-controller specificities to be supported (eg. set_fmt
that should not call into the subdev operations etc) before going too far I
decided to send this out to collect suggestions.
What is the best way to add media-controller support to a non-mc driver?
Ideally I would like this to continue working with all sensor drivers, and thus
I see a few ways of doing this:
- Keep using #ifdef CONFIG_MEDIA_CONTROLLER, but I don't see it in any other
driver in mainline
- Add a media-controller compatible string, and decide at runtime if we should
use media-controller or not (similar to what VIN driver does)
- Make the driver media controller only, but I fear 'old-style' sensor driver
won't be usable anymore with this new version.
Any pointer/opinion is welcome.
Thanks
j
---
drivers/media/platform/renesas-ceu.c | 111 +++++++++++++++++++++++++++++++++++
1 file changed, 111 insertions(+)
diff --git a/drivers/media/platform/renesas-ceu.c b/drivers/media/platform/renesas-ceu.c
index 46b0639..5911f097 100644
--- a/drivers/media/platform/renesas-ceu.c
+++ b/drivers/media/platform/renesas-ceu.c
@@ -39,6 +39,7 @@
#include <media/v4l2-fwnode.h>
#include <media/v4l2-image-sizes.h>
#include <media/v4l2-ioctl.h>
+#include <media/v4l2-mc.h>
#include <media/v4l2-mediabus.h>
#include <media/videobuf2-dma-contig.h>
@@ -158,6 +159,9 @@ struct ceu_subdev {
/* per-subdevice mbus configuration options */
unsigned int mbus_flags;
struct ceu_mbus_fmt mbus_fmt;
+#ifdef CONFIG_MEDIA_CONTROLLER
+ int source_pad;
+#endif
};
static struct ceu_subdev *to_ceu_subdev(struct v4l2_async_subdev *asd)
@@ -173,6 +177,11 @@ struct ceu_device {
struct video_device vdev;
struct v4l2_device v4l2_dev;
+#ifdef CONFIG_MEDIA_CONTROLLER
+ struct media_device mdev;
+ struct media_pad pad;
+#endif
+
/* subdevices descriptors */
struct ceu_subdev *subdevs;
/* the subdevice currently in use */
@@ -1381,6 +1390,60 @@ static void ceu_vdev_release(struct video_device *vdev)
kfree(ceudev);
}
+#ifdef CONFIG_MEDIA_CONTROLLER
+static int ceu_find_pad(struct v4l2_subdev *sd, int direction)
+{
+ unsigned int pad;
+
+ if (sd->entity.num_pads <= 1)
+ return 0;
+
+ for (pad = 0; pad < sd->entity.num_pads; pad++)
+ if (sd->entity.pads[pad].flags & direction)
+ return pad;
+
+ return -EINVAL;
+}
+
+static int ceu_notify_complete_mc(struct ceu_device *ceudev)
+{
+ struct video_device *vdev = &ceudev->vdev;
+ struct media_entity *source;
+ struct media_entity *sink;
+
+ unsigned int i;
+ int ret;
+
+ ret = media_device_register(&ceudev->mdev);
+ if (ret) {
+ v4l2_err(vdev->v4l2_dev,
+ "media_device_register failed : %d\n", ret);
+ return ret;
+ }
+
+ ret = v4l2_device_register_subdev_nodes(&ceudev->v4l2_dev);
+ if (ret)
+ return ret;
+
+ /* Link subdev's first available source pad to CEU sink one. */
+ for (i = 0; i < ceudev->num_sd; i++) {
+ int source_pad = ceudev->subdevs[i].source_pad;
+
+ if (source_pad < 0)
+ continue;
+
+ source = &ceudev->subdevs[i].v4l2_sd->entity;
+ sink = &vdev->entity;
+
+ ret = media_create_pad_link(source, source_pad, sink, 0, 0);
+ if (ret)
+ return ret;
+ }
+
+ return 0;
+}
+#endif
+
static int ceu_notify_bound(struct v4l2_async_notifier *notifier,
struct v4l2_subdev *v4l2_sd,
struct v4l2_async_subdev *asd)
@@ -1392,6 +1455,11 @@ static int ceu_notify_bound(struct v4l2_async_notifier *notifier,
ceu_sd->v4l2_sd = v4l2_sd;
ceudev->num_sd++;
+#ifdef CONFIG_MEDIA_CONTROLLER
+ /* Cache the entity source pad for later link creation. */
+ ceu_sd->source_pad = ceu_find_pad(v4l2_sd, MEDIA_PAD_FL_SOURCE);
+#endif
+
return 0;
}
@@ -1459,6 +1527,14 @@ static int ceu_notify_complete(struct v4l2_async_notifier *notifier)
return ret;
}
+#ifdef CONFIG_MEDIA_CONTROLLER
+ ret = ceu_notify_complete_mc(ceudev);
+ if (ret) {
+ video_unregister_device(&ceudev->vdev);
+ return ret;
+ }
+#endif
+
return 0;
}
@@ -1467,6 +1543,12 @@ static const struct v4l2_async_notifier_operations ceu_notify_ops = {
.complete = ceu_notify_complete,
};
+#ifdef CONFIG_MEDIA_CONTROLLER
+static const struct media_device_ops ceu_media_ops = {
+ .link_notify = v4l2_pipeline_link_notify,
+};
+#endif
+
/*
* ceu_init_async_subdevs() - Initialize CEU subdevices and async_subdevs in
* ceu device. Both DT and platform data parsing use
@@ -1631,6 +1713,9 @@ static int ceu_probe(struct platform_device *pdev)
struct device *dev = &pdev->dev;
const struct ceu_data *ceu_data;
struct ceu_device *ceudev;
+#ifdef CONFIG_MEDIA_CONTROLLER
+ struct media_device *mdev;
+#endif
struct resource *res;
unsigned int irq;
int num_subdevs;
@@ -1670,6 +1755,24 @@ static int ceu_probe(struct platform_device *pdev)
pm_runtime_enable(dev);
+#ifdef CONFIG_MEDIA_CONTROLLER
+ mdev = &ceudev->mdev;
+ mdev->dev = dev;
+ mdev->ops = &ceu_media_ops;
+ strlcpy(mdev->driver_name, KBUILD_MODNAME, sizeof(mdev->driver_name));
+ strlcpy(mdev->model, KBUILD_MODNAME, sizeof(mdev->model));
+ snprintf(mdev->bus_info, sizeof(mdev->bus_info), "platform:%s",
+ dev_name(mdev->dev));
+
+ media_device_init(mdev);
+ ceudev->v4l2_dev.mdev = mdev;
+
+ ceudev->pad.flags = MEDIA_PAD_FL_SINK;
+ ret = media_entity_pads_init(&ceudev->vdev.entity, 1, &ceudev->pad);
+ if (ret)
+ goto error_pm_disable;
+#endif
+
ret = v4l2_device_register(dev, &ceudev->v4l2_dev);
if (ret)
goto error_pm_disable;
@@ -1709,6 +1812,9 @@ static int ceu_probe(struct platform_device *pdev)
v4l2_device_unregister(&ceudev->v4l2_dev);
error_pm_disable:
pm_runtime_disable(dev);
+#ifdef CONFIG_MEDIA_CONTROLLER
+ media_device_cleanup(&ceudev->mdev);
+#endif
error_free_ceudev:
kfree(ceudev);
@@ -1723,6 +1829,11 @@ static int ceu_remove(struct platform_device *pdev)
v4l2_async_notifier_unregister(&ceudev->notifier);
+#ifdef CONFIG_MEDIA_CONTROLLER
+ media_device_cleanup(&ceudev->mdev);
+ media_device_unregister(&ceudev->mdev);
+#endif
+
v4l2_device_unregister(&ceudev->v4l2_dev);
video_unregister_device(&ceudev->vdev);
--
2.7.4
