v4l2_device_register_subdev_nodes(). Those device nodes will be automatically
removed when sub-devices are unregistered.
+The device node handles a subset of the V4L2 API.
+
+VIDIOC_QUERYCTRL
+VIDIOC_QUERYMENU
+VIDIOC_G_CTRL
+VIDIOC_S_CTRL
+VIDIOC_G_EXT_CTRLS
+VIDIOC_S_EXT_CTRLS
+VIDIOC_TRY_EXT_CTRLS
+
+ The controls ioctls are identical to the ones defined in V4L2. They
+ behave identically, with the only exception that they deal only with
+ controls implemented in the sub-device. Depending on the driver, those
+ controls can be also be accessed through one (or several) V4L2 device
+ nodes.
+
I2C sub-device drivers
----------------------
#include <linux/ioctl.h>
#include <linux/videodev2.h>
+#include <media/v4l2-ctrls.h>
#include <media/v4l2-device.h>
#include <media/v4l2-ioctl.h>
static long subdev_do_ioctl(struct file *file, unsigned int cmd, void *arg)
{
+ struct video_device *vdev = video_devdata(file);
+ struct v4l2_subdev *sd = vdev_to_v4l2_subdev(vdev);
+
switch (cmd) {
+ case VIDIOC_QUERYCTRL:
+ return v4l2_subdev_queryctrl(sd, arg);
+
+ case VIDIOC_QUERYMENU:
+ return v4l2_subdev_querymenu(sd, arg);
+
+ case VIDIOC_G_CTRL:
+ return v4l2_subdev_g_ctrl(sd, arg);
+
+ case VIDIOC_S_CTRL:
+ return v4l2_subdev_s_ctrl(sd, arg);
+
+ case VIDIOC_G_EXT_CTRLS:
+ return v4l2_subdev_g_ext_ctrls(sd, arg);
+
+ case VIDIOC_S_EXT_CTRLS:
+ return v4l2_subdev_s_ext_ctrls(sd, arg);
+
+ case VIDIOC_TRY_EXT_CTRLS:
+ return v4l2_subdev_try_ext_ctrls(sd, arg);
+
default:
return -ENOIOCTLCMD;
}