From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from perceval.ideasonboard.com ([95.142.166.194]:55107 "EHLO perceval.ideasonboard.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757790Ab3IFQan (ORCPT ); Fri, 6 Sep 2013 12:30:43 -0400 From: Laurent Pinchart To: Sakari Ailus Cc: linux-media@vger.kernel.org Subject: Re: [RFC v1.2 2/4] media: Check for active links on pads with MEDIA_PAD_FL_MUST_CONNECT flag Date: Fri, 06 Sep 2013 18:30:47 +0200 Message-ID: <2776033.HLZrjxzBOj@avalon> In-Reply-To: <1378253382-23174-1-git-send-email-sakari.ailus@iki.fi> References: <1806796.1hWpdenVOE@avalon> <1378253382-23174-1-git-send-email-sakari.ailus@iki.fi> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" Sender: linux-media-owner@vger.kernel.org List-ID: Hi Sakari, Thank you for the patch. On Wednesday 04 September 2013 03:09:42 Sakari Ailus wrote: > Do not allow streaming if a pad with MEDIA_PAD_FL_MUST_CONNECT flag is > connected by links that are all inactive. > > This patch makes it possible to avoid drivers having to check for the most > common case of link state validation: a sink pad that must be connected. > > Signed-off-by: Sakari Ailus > --- > drivers/media/media-entity.c | 41 > +++++++++++++++++++++++++++++++------ > 1 file changed, 34 insertions(+), 7 deletions(-) > > diff --git a/drivers/media/media-entity.c b/drivers/media/media-entity.c > index 2c286c3..567a171 100644 > --- a/drivers/media/media-entity.c > +++ b/drivers/media/media-entity.c > @@ -235,6 +235,8 @@ __must_check int media_entity_pipeline_start(struct > media_entity *entity, media_entity_graph_walk_start(&graph, entity); > > while ((entity = media_entity_graph_walk_next(&graph))) { > + DECLARE_BITMAP(active, entity->num_pads); > + DECLARE_BITMAP(has_no_links, entity->num_pads); > unsigned int i; > > entity->stream_count++; > @@ -248,21 +250,46 @@ __must_check int media_entity_pipeline_start(struct > media_entity *entity, if (!entity->ops || !entity->ops->link_validate) > continue; > > + bitmap_zero(active, entity->num_pads); > + bitmap_fill(has_no_links, entity->num_pads); > + > for (i = 0; i < entity->num_links; i++) { > struct media_link *link = &entity->links[i]; > - > - /* Is this pad part of an enabled link? */ > - if (!(link->flags & MEDIA_LNK_FL_ENABLED)) > - continue; > - > - /* Are we the sink or not? */ > - if (link->sink->entity != entity) > + struct media_pad *pad = link->sink->entity == entity > + ? link->sink : link->source; > + > + /* Mark that a pad is connected by a link. */ > + bitmap_clear(has_no_links, pad->index, 1); > + > + /* > + * Pads that either do not need to connect or > + * are connected through an enabled link are > + * fine. > + */ > + if (!(pad->flags & MEDIA_PAD_FL_MUST_CONNECT) > + || link->flags & MEDIA_LNK_FL_ENABLED) With the || moved on the previous line (here and below), Acked-by: Laurent Pinchart If that's fine with you there's no need to resent, I'll take the patch in my tree with that modification. > + bitmap_set(active, pad->index, 1); > + > + /* > + * Link validation will only take place for > + * sink ends of the link that are enabled. > + */ > + if (link->sink != pad > + || !(link->flags & MEDIA_LNK_FL_ENABLED)) > continue; > > ret = entity->ops->link_validate(link); > if (ret < 0 && ret != -ENOIOCTLCMD) > goto error; > } > + > + /* Either no links or validated links are fine. */ > + bitmap_or(active, active, has_no_links, entity->num_pads); > + > + if (!bitmap_full(active, entity->num_pads)) { > + ret = -EPIPE; > + goto error; > + } > } > > mutex_unlock(&mdev->graph_mutex); -- Regards, Laurent Pinchart