diff options
Diffstat (limited to 'Documentation/video4linux/v4l2-framework.txt')
| -rw-r--r-- | Documentation/video4linux/v4l2-framework.txt | 19 |
1 files changed, 10 insertions, 9 deletions
diff --git a/Documentation/video4linux/v4l2-framework.txt b/Documentation/video4linux/v4l2-framework.txt index eeae76c22a93..ff124374e9ba 100644 --- a/Documentation/video4linux/v4l2-framework.txt +++ b/Documentation/video4linux/v4l2-framework.txt @@ -184,7 +184,7 @@ may be NULL if the subdev driver does not support anything from that category. It looks like this: struct v4l2_subdev_core_ops { - int (*g_chip_ident)(struct v4l2_subdev *sd, struct v4l2_chip_ident *chip); + int (*g_chip_ident)(struct v4l2_subdev *sd, struct v4l2_dbg_chip_ident *chip); int (*log_status)(struct v4l2_subdev *sd); int (*init)(struct v4l2_subdev *sd, u32 val); ... @@ -390,16 +390,18 @@ allocated memory. You should also set these fields: -- parent: set to the parent device (same device as was used to register - v4l2_device). +- v4l2_dev: set to the v4l2_device parent device. - name: set to something descriptive and unique. -- fops: set to the file_operations struct. +- fops: set to the v4l2_file_operations struct. - ioctl_ops: if you use the v4l2_ioctl_ops to simplify ioctl maintenance (highly recommended to use this and it might become compulsory in the future!), then set this to your v4l2_ioctl_ops struct. -If you use v4l2_ioctl_ops, then you should set .unlocked_ioctl to -__video_ioctl2 or .ioctl to video_ioctl2 in your file_operations struct. +If you use v4l2_ioctl_ops, then you should set either .unlocked_ioctl or +.ioctl to video_ioctl2 in your v4l2_file_operations struct. + +The v4l2_file_operations struct is a subset of file_operations. The main +difference is that the inode argument is omitted since it is never used. video_device registration @@ -410,7 +412,7 @@ for you. err = video_register_device(vdev, VFL_TYPE_GRABBER, -1); if (err) { - video_device_release(vdev); // or kfree(my_vdev); + video_device_release(vdev); /* or kfree(my_vdev); */ return err; } @@ -516,5 +518,4 @@ void *video_drvdata(struct file *file); You can go from a video_device struct to the v4l2_device struct using: -struct v4l2_device *v4l2_dev = dev_get_drvdata(vdev->parent); - +struct v4l2_device *v4l2_dev = vdev->v4l2_dev; |