[media] v4l: subdev: Add device node support
Create a device node named subdevX for every registered subdev.
As the device node is registered before the subdev core::s_config
function is called, return -EGAIN on open until initialization
completes.
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Vimarsh Zutshi <vimarsh.zutshi@gmail.com>
Acked-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
diff --git a/include/media/v4l2-dev.h b/include/media/v4l2-dev.h
index 15802a0..4fe6831 100644
--- a/include/media/v4l2-dev.h
+++ b/include/media/v4l2-dev.h
@@ -21,7 +21,8 @@
#define VFL_TYPE_GRABBER 0
#define VFL_TYPE_VBI 1
#define VFL_TYPE_RADIO 2
-#define VFL_TYPE_MAX 3
+#define VFL_TYPE_SUBDEV 3
+#define VFL_TYPE_MAX 4
struct v4l2_ioctl_callbacks;
struct video_device;
@@ -102,15 +103,26 @@
/* dev to video-device */
#define to_video_device(cd) container_of(cd, struct video_device, dev)
+int __must_check __video_register_device(struct video_device *vdev, int type,
+ int nr, int warn_if_nr_in_use, struct module *owner);
+
/* Register video devices. Note that if video_register_device fails,
the release() callback of the video_device structure is *not* called, so
the caller is responsible for freeing any data. Usually that means that
you call video_device_release() on failure. */
-int __must_check video_register_device(struct video_device *vdev, int type, int nr);
+static inline int __must_check video_register_device(struct video_device *vdev,
+ int type, int nr)
+{
+ return __video_register_device(vdev, type, nr, 1, vdev->fops->owner);
+}
/* Same as video_register_device, but no warning is issued if the desired
device node number was already in use. */
-int __must_check video_register_device_no_warn(struct video_device *vdev, int type, int nr);
+static inline int __must_check video_register_device_no_warn(
+ struct video_device *vdev, int type, int nr)
+{
+ return __video_register_device(vdev, type, nr, 0, vdev->fops->owner);
+}
/* Unregister video devices. Will do nothing if vdev == NULL or
video_is_registered() returns false. */
diff --git a/include/media/v4l2-device.h b/include/media/v4l2-device.h
index b16f307..78b11e5 100644
--- a/include/media/v4l2-device.h
+++ b/include/media/v4l2-device.h
@@ -96,6 +96,12 @@
wasn't registered. In that case it will do nothing. */
void v4l2_device_unregister_subdev(struct v4l2_subdev *sd);
+/* Register device nodes for all subdev of the v4l2 device that are marked with
+ * the V4L2_SUBDEV_FL_HAS_DEVNODE flag.
+ */
+int __must_check
+v4l2_device_register_subdev_nodes(struct v4l2_device *v4l2_dev);
+
/* Iterate over all subdevs. */
#define v4l2_device_for_each_subdev(sd, v4l2_dev) \
list_for_each_entry(sd, &(v4l2_dev)->subdevs, list)
diff --git a/include/media/v4l2-subdev.h b/include/media/v4l2-subdev.h
index da16d2f..474ef00 100644
--- a/include/media/v4l2-subdev.h
+++ b/include/media/v4l2-subdev.h
@@ -22,6 +22,7 @@
#define _V4L2_SUBDEV_H
#include <media/v4l2-common.h>
+#include <media/v4l2-dev.h>
#include <media/v4l2-mediabus.h>
/* generic v4l2_device notify callback notification values */
@@ -431,9 +432,11 @@
#define V4L2_SUBDEV_NAME_SIZE 32
/* Set this flag if this subdev is a i2c device. */
-#define V4L2_SUBDEV_FL_IS_I2C (1U << 0)
+#define V4L2_SUBDEV_FL_IS_I2C (1U << 0)
/* Set this flag if this subdev is a spi device. */
-#define V4L2_SUBDEV_FL_IS_SPI (1U << 1)
+#define V4L2_SUBDEV_FL_IS_SPI (1U << 1)
+/* Set this flag if this subdev needs a device node. */
+#define V4L2_SUBDEV_FL_HAS_DEVNODE (1U << 2)
/* Each instance of a subdev driver should create this struct, either
stand-alone or embedded in a larger struct.
@@ -455,8 +458,15 @@
/* pointer to private data */
void *dev_priv;
void *host_priv;
+ /* subdev device node */
+ struct video_device devnode;
};
+#define vdev_to_v4l2_subdev(vdev) \
+ container_of(vdev, struct v4l2_subdev, devnode)
+
+extern const struct v4l2_file_operations v4l2_subdev_fops;
+
static inline void v4l2_set_subdevdata(struct v4l2_subdev *sd, void *p)
{
sd->dev_priv = p;