From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from lists.s-osg.org ([54.187.51.154]:39319 "EHLO lists.s-osg.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751039AbbLLPf7 (ORCPT ); Sat, 12 Dec 2015 10:35:59 -0500 Date: Sat, 12 Dec 2015 13:35:54 -0200 From: Mauro Carvalho Chehab To: Sakari Ailus Cc: linux-media@vger.kernel.org, laurent.pinchart@ideasonboard.com, hverkuil@xs4all.nl, javier@osg.samsung.com Subject: Re: [PATCH v2 22/22] media: Update media graph walk documentation for the changed API Message-ID: <20151212133554.646c9a05@recife.lan> In-Reply-To: <1448824823-10372-23-git-send-email-sakari.ailus@iki.fi> References: <1448824823-10372-1-git-send-email-sakari.ailus@iki.fi> <1448824823-10372-23-git-send-email-sakari.ailus@iki.fi> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-media-owner@vger.kernel.org List-ID: Em Sun, 29 Nov 2015 21:20:23 +0200 Sakari Ailus escreveu: > media_entity_graph_walk_init() and media_entity_graph_walk_cleanup() are > now mandatory. > > Signed-off-by: Sakari Ailus > --- > Documentation/media-framework.txt | 22 +++++++++++++++++----- This patch needs to be reworked, as the media framework documentation got moved to kernel-doc. > 1 file changed, 17 insertions(+), 5 deletions(-) > > diff --git a/Documentation/media-framework.txt b/Documentation/media-framework.txt > index b424de6..738a526 100644 > --- a/Documentation/media-framework.txt > +++ b/Documentation/media-framework.txt > @@ -241,13 +241,22 @@ supported by the graph traversal API. To prevent infinite loops, the graph > traversal code limits the maximum depth to MEDIA_ENTITY_ENUM_MAX_DEPTH, > currently defined as 16. > > -Drivers initiate a graph traversal by calling > +The graph traversal must be initialised calling > + > + media_entity_graph_walk_init(struct media_entity_graph *graph); > + > +The return value of the function must be checked. Should the number of > +graph entities exceed the pre-allocated memory, it will also allocate > +memory for the enumeration. > + > +Once initialised, the graph walk may be started by calling > > media_entity_graph_walk_start(struct media_entity_graph *graph, > struct media_entity *entity); > > -The graph structure, provided by the caller, is initialized to start graph > -traversal at the given entity. > +The graph structure, provided by the caller, is initialized to start > +graph traversal at the given entity. It is possible to start the graph > +walk multiple times using the same graph struct. > > Drivers can then retrieve the next entity by calling > > @@ -255,8 +264,11 @@ Drivers can then retrieve the next entity by calling > > When the graph traversal is complete the function will return NULL. > > -Graph traversal can be interrupted at any moment. No cleanup function call is > -required and the graph structure can be freed normally. > +Graph traversal can be interrupted at any moment. Once the graph > +structure is no longer needed, the resources that have been allocated > +by media_entity_graph_walk_init() are released using > + > + media_entity_graph_walk_cleanup(struct media_entity_graph *graph); > > Helper functions can be used to find a link between two given pads, or a pad > connected to another pad through an enabled link