Re: [PATCH 01/18] media: v4l: async: Return async sub-devices to subnotifier list

[Laurent Pinchart <laurent.pinchart@ideasonboard.com>]

Hi Sakari,

Thank you for the patch.

On Thu, Mar 30, 2023 at 02:58:36PM +0300, Sakari Ailus wrote:
> When an async notifier is unregistered, the async sub-devices in the
> notifier's done list will disappear with the notifier. However this is
> currently also done to the sub-notifiers that remain registered. Their
> sub-devices only need to be unbound while the async sub-devices themselves
> need to be returned to the sub-notifier's waiting list. Do this now.
> 
> Fixes: 2cab00bb076b ("media: v4l: async: Allow binding notifiers to sub-devices")
> Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
> ---
>  drivers/media/v4l2-core/v4l2-async.c | 13 ++++++++-----
>  1 file changed, 8 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/media/v4l2-core/v4l2-async.c b/drivers/media/v4l2-core/v4l2-async.c
> index 2f1b718a9189..008a2a3e312e 100644
> --- a/drivers/media/v4l2-core/v4l2-async.c
> +++ b/drivers/media/v4l2-core/v4l2-async.c
> @@ -414,7 +414,8 @@ static void v4l2_async_cleanup(struct v4l2_subdev *sd)
>  
>  /* Unbind all sub-devices in the notifier tree. */
>  static void
> -v4l2_async_nf_unbind_all_subdevs(struct v4l2_async_notifier *notifier)
> +v4l2_async_nf_unbind_all_subdevs(struct v4l2_async_notifier *notifier,
> +				 bool readd)

I've read this as "read d" and was wondering what it meant. Maybe
"re_add" would be a better variable name ?

Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

>  {
>  	struct v4l2_subdev *sd, *tmp;
>  
> @@ -423,9 +424,11 @@ v4l2_async_nf_unbind_all_subdevs(struct v4l2_async_notifier *notifier)
>  			v4l2_async_find_subdev_notifier(sd);
>  
>  		if (subdev_notifier)
> -			v4l2_async_nf_unbind_all_subdevs(subdev_notifier);
> +			v4l2_async_nf_unbind_all_subdevs(subdev_notifier, true);
>  
>  		v4l2_async_nf_call_unbind(notifier, sd, sd->asd);
> +		if (readd)
> +			list_add_tail(&sd->asd->list, &notifier->waiting);
>  		v4l2_async_cleanup(sd);
>  
>  		list_move(&sd->async_list, &subdev_list);
> @@ -557,7 +560,7 @@ static int __v4l2_async_nf_register(struct v4l2_async_notifier *notifier)
>  	/*
>  	 * On failure, unbind all sub-devices registered through this notifier.
>  	 */
> -	v4l2_async_nf_unbind_all_subdevs(notifier);
> +	v4l2_async_nf_unbind_all_subdevs(notifier, false);
>  
>  err_unlock:
>  	mutex_unlock(&list_lock);
> @@ -607,7 +610,7 @@ __v4l2_async_nf_unregister(struct v4l2_async_notifier *notifier)
>  	if (!notifier || (!notifier->v4l2_dev && !notifier->sd))
>  		return;
>  
> -	v4l2_async_nf_unbind_all_subdevs(notifier);
> +	v4l2_async_nf_unbind_all_subdevs(notifier, false);
>  
>  	notifier->sd = NULL;
>  	notifier->v4l2_dev = NULL;
> @@ -805,7 +808,7 @@ int v4l2_async_register_subdev(struct v4l2_subdev *sd)
>  	 */
>  	subdev_notifier = v4l2_async_find_subdev_notifier(sd);
>  	if (subdev_notifier)
> -		v4l2_async_nf_unbind_all_subdevs(subdev_notifier);
> +		v4l2_async_nf_unbind_all_subdevs(subdev_notifier, false);
>  
>  	if (sd->asd)
>  		v4l2_async_nf_call_unbind(notifier, sd, sd->asd);

-- 
Regards,

Laurent Pinchart