On Thu, May 03, 2018 at 04:52:55PM +0200, Hans Verkuil wrote:
> From: Hans Verkuil <hans.verkuil@xxxxxxxxx>
>
> Add media_request_object_find to find a request object inside a
> request based on ops and/or priv values.
>
> Objects of the same type (vb2 buffer, control handler) will have
> the same ops value. And objects that refer to the same 'parent'
> object (e.g. the v4l2_ctrl_handler that has the current driver
> state) will have the same priv value.
>
> The caller has to call media_request_object_put() for the returned
> object since this function increments the refcount.
>
> Signed-off-by: Hans Verkuil <hans.verkuil@xxxxxxxxx>
> ---
> drivers/media/media-request.c | 25 +++++++++++++++++++++++++
> include/media/media-request.h | 24 ++++++++++++++++++++++++
> 2 files changed, 49 insertions(+)
>
> diff --git a/drivers/media/media-request.c b/drivers/media/media-request.c
> index edc1c3af1959..c7e11e816e27 100644
> --- a/drivers/media/media-request.c
> +++ b/drivers/media/media-request.c
> @@ -322,6 +322,31 @@ static void media_request_object_release(struct kref *kref)
> obj->ops->release(obj);
> }
>
> +struct media_request_object *
> +media_request_object_find(struct media_request *req,
> + const struct media_request_object_ops *ops,
> + void *priv)
> +{
> + struct media_request_object *obj;
> + struct media_request_object *found = NULL;
> + unsigned long flags;
> +
> + if (WARN_ON(!ops || !priv))
> + return NULL;
> +
> + spin_lock_irqsave(&req->lock, flags);
> + list_for_each_entry(obj, &req->objects, list) {
> + if (obj->ops == ops && obj->priv == priv) {
> + media_request_object_get(obj);
> + found = obj;
> + break;
> + }
> + }
> + spin_unlock_irqrestore(&req->lock, flags);
> + return found;
> +}
> +EXPORT_SYMBOL_GPL(media_request_object_find);
> +
> void media_request_object_put(struct media_request_object *obj)
> {
> kref_put(&obj->kref, media_request_object_release);
> diff --git a/include/media/media-request.h b/include/media/media-request.h
> index 997e096d7128..5367b4a2f91c 100644
> --- a/include/media/media-request.h
> +++ b/include/media/media-request.h
> @@ -196,6 +196,22 @@ static inline void media_request_object_get(struct media_request_object *obj)
> */
> void media_request_object_put(struct media_request_object *obj);
>
> +/**
> + * media_request_object_find - Find an object in a request
> + *
> + * @ops: Find an object with this ops value
> + * @priv: Find an object with this priv value
> + *
> + * Both @ops and @priv must be non-NULL.
> + *
> + * Returns NULL if not found or the object pointer. The caller must
I'd describe the successful case first. I.e. "Returns the object pointer or
NULL it not found".
Acked-by: Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxx>
> + * call media_request_object_put() once it finished using the object.
> + */
> +struct media_request_object *
> +media_request_object_find(struct media_request *req,
> + const struct media_request_object_ops *ops,
> + void *priv);
> +
> /**
> * media_request_object_init - Initialise a media request object
> *
> @@ -241,6 +257,14 @@ static inline void media_request_object_put(struct media_request_object *obj)
> {
> }
>
> +static inline struct media_request_object *
> +media_request_object_find(struct media_request *req,
> + const struct media_request_object_ops *ops,
> + void *priv)
> +{
> + return NULL;
> +}
> +
> static inline void media_request_object_init(struct media_request_object *obj)
> {
> obj->ops = NULL;
--
Sakari Ailus
e-mail: sakari.ailus@xxxxxx
