Re: [PATCH v16 17/32] v4l: async: Prepare for async sub-device notifiers

Niklas Söderlund
2017-10-26T22:10:51Z

On 2017-10-26 10:53:27 +0300, Sakari Ailus wrote:
> Refactor the V4L2 async framework a little in preparation for async
> sub-device notifiers. This avoids making some structural changes in the
> patch actually implementing sub-device notifiers, making that patch easier
> to review.
>
> Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
> Acked-by: Hans Verkuil <hans.verkuil@cisco.com>

Acked-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>

> ---
> drivers/media/v4l2-core/v4l2-async.c | 71 ++++++++++++++++++++++++++----------
> 1 file changed, 52 insertions(+), 19 deletions(-)
>
> diff --git a/drivers/media/v4l2-core/v4l2-async.c b/drivers/media/v4l2-core/v4l2-async.c
> index 1b536d68cedf..eb31d96254d1 100644
> --- a/drivers/media/v4l2-core/v4l2-async.c
> +++ b/drivers/media/v4l2-core/v4l2-async.c
> @@ -125,12 +125,13 @@ static struct v4l2_async_subdev *v4l2_async_find_match(
> }
>
> static int v4l2_async_match_notify(struct v4l2_async_notifier *notifier,
> + struct v4l2_device *v4l2_dev,
> struct v4l2_subdev *sd,
> struct v4l2_async_subdev *asd)
> {
> int ret;
>
> - ret = v4l2_device_register_subdev(notifier->v4l2_dev, sd);
> + ret = v4l2_device_register_subdev(v4l2_dev, sd);
> if (ret < 0)
> return ret;
>
> @@ -151,6 +152,31 @@ static int v4l2_async_match_notify(struct v4l2_async_notifier *notifier,
> return 0;
> }
>
> +/* Test all async sub-devices in a notifier for a match. */
> +static int v4l2_async_notifier_try_all_subdevs(
> + struct v4l2_async_notifier *notifier)
> +{
> + struct v4l2_device *v4l2_dev = notifier->v4l2_dev;
> + struct v4l2_subdev *sd, *tmp;
> +
> + list_for_each_entry_safe(sd, tmp, &subdev_list, async_list) {
> + struct v4l2_async_subdev *asd;
> + int ret;
> +
> + asd = v4l2_async_find_match(notifier, sd);
> + if (!asd)
> + continue;
> +
> + ret = v4l2_async_match_notify(notifier, v4l2_dev, sd, asd);
> + if (ret < 0) {
> + mutex_unlock(&list_lock);
> + return ret;
> + }
> + }
> +
> + return 0;
> +}
> +
> static void v4l2_async_cleanup(struct v4l2_subdev *sd)
> {
> v4l2_device_unregister_subdev(sd);
> @@ -172,18 +198,15 @@ static void v4l2_async_notifier_unbind_all_subdevs(
> }
> }
>
> -int v4l2_async_notifier_register(struct v4l2_device *v4l2_dev,
> - struct v4l2_async_notifier *notifier)
> +static int __v4l2_async_notifier_register(struct v4l2_async_notifier *notifier)
> {
> - struct v4l2_subdev *sd, *tmp;
> struct v4l2_async_subdev *asd;
> int ret;
> int i;
>
> - if (!v4l2_dev || notifier->num_subdevs > V4L2_MAX_SUBDEVS)
> + if (notifier->num_subdevs > V4L2_MAX_SUBDEVS)
> return -EINVAL;
>
> - notifier->v4l2_dev = v4l2_dev;
> INIT_LIST_HEAD(&notifier->waiting);
> INIT_LIST_HEAD(&notifier->done);
>
> @@ -216,18 +239,10 @@ int v4l2_async_notifier_register(struct v4l2_device *v4l2_dev,
>
> mutex_lock(&list_lock);
>
> - list_for_each_entry_safe(sd, tmp, &subdev_list, async_list) {
> - int ret;
> -
> - asd = v4l2_async_find_match(notifier, sd);
> - if (!asd)
> - continue;
> -
> - ret = v4l2_async_match_notify(notifier, sd, asd);
> - if (ret < 0) {
> - mutex_unlock(&list_lock);
> - return ret;
> - }
> + ret = v4l2_async_notifier_try_all_subdevs(notifier);
> + if (ret) {
> + mutex_unlock(&list_lock);
> + return ret;
> }
>
> if (list_empty(&notifier->waiting)) {
> @@ -250,6 +265,23 @@ int v4l2_async_notifier_register(struct v4l2_device *v4l2_dev,
>
> return ret;
> }
> +
> +int v4l2_async_notifier_register(struct v4l2_device *v4l2_dev,
> + struct v4l2_async_notifier *notifier)
> +{
> + int ret;
> +
> + if (WARN_ON(!v4l2_dev))
> + return -EINVAL;
> +
> + notifier->v4l2_dev = v4l2_dev;
> +
> + ret = __v4l2_async_notifier_register(notifier);
> + if (ret)
> + notifier->v4l2_dev = NULL;
> +
> + return ret;
> +}
> EXPORT_SYMBOL(v4l2_async_notifier_register);
>
> void v4l2_async_notifier_unregister(struct v4l2_async_notifier *notifier)
> @@ -324,7 +356,8 @@ int v4l2_async_register_subdev(struct v4l2_subdev *sd)
> if (!asd)
> continue;
>
> - ret = v4l2_async_match_notify(notifier, sd, asd);
> + ret = v4l2_async_match_notify(notifier, notifier->v4l2_dev, sd,
> + asd);
> if (ret)
> goto err_unlock;
>
> --
> 2.11.0
>

--
Regards,
Niklas Söderlund