| Message ID | 20220630230713.10580-4-laurent.pinchart@ideasonboard.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | media: rkisp1: Cleanups and add support for i.MX8MP | expand |
On 7/1/22 01:06, Laurent Pinchart wrote: > The media_entity_remote_pad() helper function returns the first remote The function name is now out of date after the previous patch, it should be media_entity_remote_pad_first(). Regards, Hans > pad it find connected to a given pad. Beside being possibly > non-deterministic (as it stops at the first enabled link), the fact that > it returns the first match makes it unsuitable for drivers that need to > guarantee that a single link is enabled, for instance when an entity can > process data from one of multiple sources at a time. > > For those use cases, add a new helper function, > media_entity_remote_pad_unique(), that operates on an entity and returns > a remote pad, with a guarantee that only one link is enabled. To ease > its use in drivers, also add an inline wrapper that locates source pads > specifically. A wrapper that locates sink pads can easily be added when > needed. > > Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> > Acked-by: Hans Verkuil <hverkuil-cisco@xs4all.nl> > --- > Changes since v1: > > - Rename media_entity_remote_source_pad() to > media_entity_remote_source_pad_unique() > - Skip non-data links > --- > Documentation/driver-api/media/mc-core.rst | 3 +- > drivers/media/mc/mc-entity.c | 40 +++++++++++++++++++ > include/media/media-entity.h | 46 ++++++++++++++++++++++ > 3 files changed, 88 insertions(+), 1 deletion(-) > > diff --git a/Documentation/driver-api/media/mc-core.rst b/Documentation/driver-api/media/mc-core.rst > index 6eea6a3b6441..66801506b2dd 100644 > --- a/Documentation/driver-api/media/mc-core.rst > +++ b/Documentation/driver-api/media/mc-core.rst > @@ -186,7 +186,8 @@ is required and the graph structure can be freed normally. > > Helper functions can be used to find a link between two given pads, or a pad > connected to another pad through an enabled link > -:c:func:`media_entity_find_link()` and :c:func:`media_pad_remote_pad_first()`. > +(:c:func:`media_entity_find_link()`, :c:func:`media_pad_remote_pad_first()` and > +:c:func:`media_entity_remote_source_pad_unique()`). > > Use count and power handling > ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ > diff --git a/drivers/media/mc/mc-entity.c b/drivers/media/mc/mc-entity.c > index 55076fea7b58..bd7145932137 100644 > --- a/drivers/media/mc/mc-entity.c > +++ b/drivers/media/mc/mc-entity.c > @@ -9,6 +9,7 @@ > */ > > #include <linux/bitmap.h> > +#include <linux/list.h> > #include <linux/property.h> > #include <linux/slab.h> > #include <media/media-entity.h> > @@ -920,6 +921,45 @@ struct media_pad *media_pad_remote_pad_first(const struct media_pad *pad) > } > EXPORT_SYMBOL_GPL(media_pad_remote_pad_first); > > +struct media_pad * > +media_entity_remote_pad_unique(const struct media_entity *entity, > + unsigned int type) > +{ > + struct media_pad *pad = NULL; > + struct media_link *link; > + > + list_for_each_entry(link, &entity->links, list) { > + struct media_pad *local_pad; > + struct media_pad *remote_pad; > + > + if (((link->flags & MEDIA_LNK_FL_LINK_TYPE) != > + MEDIA_LNK_FL_DATA_LINK) || > + !(link->flags & MEDIA_LNK_FL_ENABLED)) > + continue; > + > + if (type == MEDIA_PAD_FL_SOURCE) { > + local_pad = link->sink; > + remote_pad = link->source; > + } else { > + local_pad = link->source; > + remote_pad = link->sink; > + } > + > + if (local_pad->entity == entity) { > + if (pad) > + return ERR_PTR(-ENOTUNIQ); > + > + pad = remote_pad; > + } > + } > + > + if (!pad) > + return ERR_PTR(-ENOLINK); > + > + return pad; > +} > +EXPORT_SYMBOL_GPL(media_entity_remote_pad_unique); > + > static void media_interface_init(struct media_device *mdev, > struct media_interface *intf, > u32 gobj_type, > diff --git a/include/media/media-entity.h b/include/media/media-entity.h > index ab84476b25c8..aecd1691b297 100644 > --- a/include/media/media-entity.h > +++ b/include/media/media-entity.h > @@ -859,6 +859,52 @@ struct media_link *media_entity_find_link(struct media_pad *source, > */ > struct media_pad *media_pad_remote_pad_first(const struct media_pad *pad); > > +/** > + * media_entity_remote_pad_unique - Find a remote pad connected to an entity > + * @entity: The entity > + * @type: The type of pad to find (MEDIA_PAD_FL_SINK or MEDIA_PAD_FL_SOURCE) > + * > + * Search for and return a remote pad of @type connected to @entity through an > + * enabled link. If multiple (or no) remote pads match these criteria, an error > + * is returned. > + * > + * The uniqueness constraint makes this helper function suitable for entities > + * that support a single active source or sink at a time. > + * > + * Return: A pointer to the remote pad, or one of the following error pointers > + * if an error occurs: > + * > + * * -ENOTUNIQ - Multiple links are enabled > + * * -ENOLINK - No connected pad found > + */ > +struct media_pad * > +media_entity_remote_pad_unique(const struct media_entity *entity, > + unsigned int type); > + > +/** > + * media_entity_remote_source_pad_unique - Find a remote source pad connected to > + * an entity > + * @entity: The entity > + * > + * Search for and return a remote source pad connected to @entity through an > + * enabled link. If multiple (or no) remote pads match these criteria, an error > + * is returned. > + * > + * The uniqueness constraint makes this helper function suitable for entities > + * that support a single active source at a time. > + * > + * Return: A pointer to the remote pad, or one of the following error pointers > + * if an error occurs: > + * > + * * -ENOTUNIQ - Multiple links are enabled > + * * -ENOLINK - No connected pad found > + */ > +static inline struct media_pad * > +media_entity_remote_source_pad_unique(const struct media_entity *entity) > +{ > + return media_entity_remote_pad_unique(entity, MEDIA_PAD_FL_SOURCE); > +} > + > /** > * media_entity_is_streaming - Test if an entity is part of a streaming pipeline > * @entity: The entity
diff --git a/Documentation/driver-api/media/mc-core.rst b/Documentation/driver-api/media/mc-core.rst index 6eea6a3b6441..66801506b2dd 100644 --- a/Documentation/driver-api/media/mc-core.rst +++ b/Documentation/driver-api/media/mc-core.rst @@ -186,7 +186,8 @@ is required and the graph structure can be freed normally. Helper functions can be used to find a link between two given pads, or a pad connected to another pad through an enabled link -:c:func:`media_entity_find_link()` and :c:func:`media_pad_remote_pad_first()`. +(:c:func:`media_entity_find_link()`, :c:func:`media_pad_remote_pad_first()` and +:c:func:`media_entity_remote_source_pad_unique()`). Use count and power handling ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ diff --git a/drivers/media/mc/mc-entity.c b/drivers/media/mc/mc-entity.c index 55076fea7b58..bd7145932137 100644 --- a/drivers/media/mc/mc-entity.c +++ b/drivers/media/mc/mc-entity.c @@ -9,6 +9,7 @@ */ #include <linux/bitmap.h> +#include <linux/list.h> #include <linux/property.h> #include <linux/slab.h> #include <media/media-entity.h> @@ -920,6 +921,45 @@ struct media_pad *media_pad_remote_pad_first(const struct media_pad *pad) } EXPORT_SYMBOL_GPL(media_pad_remote_pad_first); +struct media_pad * +media_entity_remote_pad_unique(const struct media_entity *entity, + unsigned int type) +{ + struct media_pad *pad = NULL; + struct media_link *link; + + list_for_each_entry(link, &entity->links, list) { + struct media_pad *local_pad; + struct media_pad *remote_pad; + + if (((link->flags & MEDIA_LNK_FL_LINK_TYPE) != + MEDIA_LNK_FL_DATA_LINK) || + !(link->flags & MEDIA_LNK_FL_ENABLED)) + continue; + + if (type == MEDIA_PAD_FL_SOURCE) { + local_pad = link->sink; + remote_pad = link->source; + } else { + local_pad = link->source; + remote_pad = link->sink; + } + + if (local_pad->entity == entity) { + if (pad) + return ERR_PTR(-ENOTUNIQ); + + pad = remote_pad; + } + } + + if (!pad) + return ERR_PTR(-ENOLINK); + + return pad; +} +EXPORT_SYMBOL_GPL(media_entity_remote_pad_unique); + static void media_interface_init(struct media_device *mdev, struct media_interface *intf, u32 gobj_type, diff --git a/include/media/media-entity.h b/include/media/media-entity.h index ab84476b25c8..aecd1691b297 100644 --- a/include/media/media-entity.h +++ b/include/media/media-entity.h @@ -859,6 +859,52 @@ struct media_link *media_entity_find_link(struct media_pad *source, */ struct media_pad *media_pad_remote_pad_first(const struct media_pad *pad); +/** + * media_entity_remote_pad_unique - Find a remote pad connected to an entity + * @entity: The entity + * @type: The type of pad to find (MEDIA_PAD_FL_SINK or MEDIA_PAD_FL_SOURCE) + * + * Search for and return a remote pad of @type connected to @entity through an + * enabled link. If multiple (or no) remote pads match these criteria, an error + * is returned. + * + * The uniqueness constraint makes this helper function suitable for entities + * that support a single active source or sink at a time. + * + * Return: A pointer to the remote pad, or one of the following error pointers + * if an error occurs: + * + * * -ENOTUNIQ - Multiple links are enabled + * * -ENOLINK - No connected pad found + */ +struct media_pad * +media_entity_remote_pad_unique(const struct media_entity *entity, + unsigned int type); + +/** + * media_entity_remote_source_pad_unique - Find a remote source pad connected to + * an entity + * @entity: The entity + * + * Search for and return a remote source pad connected to @entity through an + * enabled link. If multiple (or no) remote pads match these criteria, an error + * is returned. + * + * The uniqueness constraint makes this helper function suitable for entities + * that support a single active source at a time. + * + * Return: A pointer to the remote pad, or one of the following error pointers + * if an error occurs: + * + * * -ENOTUNIQ - Multiple links are enabled + * * -ENOLINK - No connected pad found + */ +static inline struct media_pad * +media_entity_remote_source_pad_unique(const struct media_entity *entity) +{ + return media_entity_remote_pad_unique(entity, MEDIA_PAD_FL_SOURCE); +} + /** * media_entity_is_streaming - Test if an entity is part of a streaming pipeline * @entity: The entity