Re: [PATCH 4/8] V4L: Events: Support event handling in do_ioctl

[Sakari Ailus <sakari.ailus@maxwell.research.nokia.com>]

Sakari Ailus wrote:
> Add support for event handling to do_ioctl.
> 
> Signed-off-by: Sakari Ailus <sakari.ailus@maxwell.research.nokia.com>
...
> @@ -239,6 +241,13 @@ struct v4l2_ioctl_ops {
>  	int (*vidioc_enum_frameintervals) (struct file *file, void *fh,
>  					   struct v4l2_frmivalenum *fival);
>  
> +	int (*vidioc_dqevent)	       (struct v4l2_fh *fh,
> +					struct v4l2_event *ev);
> +	int (*vidioc_subscribe_event)  (struct v4l2_fh *fh,
> +					struct v4l2_event_subscription *sub);
> +	int (*vidioc_unsubscribe_event) (struct v4l2_fh *fh,
> +					 struct v4l2_event_subscription *sub);
> +
>  	/* For other private ioctls */
>  	long (*vidioc_default)	       (struct file *file, void *fh,
>  					int cmd, void *arg);

Replying to myself, there seems to be valid use for the struct file as
an argument to the function fields. That is a way to get the video
device pointer using video_devdata(). Otherwise the video device pointer
has to be stored in the file handle instead.

So I'm going to add the file pointers as first arguments here as they
are in other functions unless there are objections. The type of second
argument is still going to be struct v4l2_fh *.

Regards,

-- 
Sakari Ailus
sakari.ailus@maxwell.research.nokia.com