From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2C488C10DCE for ; Wed, 18 Mar 2020 13:35:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id F1D5520774 for ; Wed, 18 Mar 2020 13:35:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726774AbgCRNfr (ORCPT ); Wed, 18 Mar 2020 09:35:47 -0400 Received: from mga06.intel.com ([134.134.136.31]:1648 "EHLO mga06.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726730AbgCRNfr (ORCPT ); Wed, 18 Mar 2020 09:35:47 -0400 IronPort-SDR: hpdb0WMWeXzW5ipTbiC7iT818n1BmZJ4uTEQa3Af72XSFDtNjpguqnXzGqiyJdxCC8KA3ybWvr gLjA3a0COXpw== X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga004.fm.intel.com ([10.253.24.48]) by orsmga104.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 18 Mar 2020 06:35:45 -0700 IronPort-SDR: we0QHrzQNcKw7fZginFbDUW6PMdYAPr54ieQT+Pm+Ip7gNObAkhHJtyXX3F+HxA8s4/R+xf7yP b7BjyVCOtD+A== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.70,567,1574150400"; d="scan'208";a="268356791" Received: from thoyle-mobl.ger.corp.intel.com (HELO kekkonen.fi.intel.com) ([10.252.45.52]) by fmsmga004.fm.intel.com with ESMTP; 18 Mar 2020 06:35:43 -0700 Received: by kekkonen.fi.intel.com (Postfix, from userid 1000) id 2267121F46; Wed, 18 Mar 2020 15:35:37 +0200 (EET) Date: Wed, 18 Mar 2020 15:35:36 +0200 From: Sakari Ailus To: Laurent Pinchart Cc: Laurent Pinchart , linux-media@vger.kernel.org, Jacopo Mondi , Niklas =?iso-8859-1?Q?S=F6derlund?= , Kieran Bingham , Lad Prabhakar Subject: Re: [PATCH] media: v4l2-async: Accept endpoints and devices for fwnode matching Message-ID: <20200318133536.GD15448@kekkonen.localdomain> References: <20200315102724.26850-1-prabhakar.mahadev-lad.rj@bp.renesas.com> <20200315125511.25756-1-laurent.pinchart+renesas@ideasonboard.com> <20200317124455.GC13878@kekkonen.localdomain> <20200317230432.GO2527@pendragon.ideasonboard.com> <20200318001726.GQ2527@pendragon.ideasonboard.com> <20200318075225.GA2101@mara.localdomain> <20200318112216.GC4733@pendragon.ideasonboard.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200318112216.GC4733@pendragon.ideasonboard.com> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-media-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org Hi Laurent, On Wed, Mar 18, 2020 at 01:22:16PM +0200, Laurent Pinchart wrote: > Hi Sakari, > > On Wed, Mar 18, 2020 at 09:52:25AM +0200, Sakari Ailus wrote: > > On Wed, Mar 18, 2020 at 02:17:26AM +0200, Laurent Pinchart wrote: > > > On Wed, Mar 18, 2020 at 01:04:32AM +0200, Laurent Pinchart wrote: > > >> On Tue, Mar 17, 2020 at 02:44:56PM +0200, Sakari Ailus wrote: > > >>> On Sun, Mar 15, 2020 at 02:55:11PM +0200, Laurent Pinchart wrote: > > >>>> fwnode matching was designed to match on nodes corresponding to a > > >>>> device. Some drivers, however, needed to match on endpoints, and have > > >>>> passed endpoint fwnodes to v4l2-async. This works when both the subdev > > >>>> and the notifier use the same fwnode types (endpoint or device), but > > >>>> makes drivers that use different types incompatible. > > >>>> > > >>>> Fix this by extending the fwnode match to handle fwnodes of different > > >>>> types. When the types (deduced from the node name) are different, > > >>>> retrieve the device fwnode for the side that provides an endpoint > > >>>> fwnode, and compare it with the device fwnode provided by the other > > >>>> side. This allows interoperability between all drivers, regardless of > > >>>> which type of fwnode they use for matching. > > >>>> > > >>>> Signed-off-by: Laurent Pinchart > > >>>> --- > > >>>> This has been compile-tested only. Prabhakar, could you check if it > > >>>> fixes your issue ? > > >>>> > > >>>> drivers/media/v4l2-core/v4l2-async.c | 42 +++++++++++++++++++++++++++- > > >>>> 1 file changed, 41 insertions(+), 1 deletion(-) > > >>>> > > >>>> diff --git a/drivers/media/v4l2-core/v4l2-async.c b/drivers/media/v4l2-core/v4l2-async.c > > >>>> index 8bde33c21ce4..995e5464cba7 100644 > > >>>> --- a/drivers/media/v4l2-core/v4l2-async.c > > >>>> +++ b/drivers/media/v4l2-core/v4l2-async.c > > >>>> @@ -71,7 +71,47 @@ static bool match_devname(struct v4l2_subdev *sd, > > >>>> > > >>>> static bool match_fwnode(struct v4l2_subdev *sd, struct v4l2_async_subdev *asd) > > >>>> { > > >>>> - return sd->fwnode == asd->match.fwnode; > > >>>> + struct fwnode_handle *other_fwnode; > > >>>> + struct fwnode_handle *dev_fwnode; > > >>>> + bool asd_fwnode_is_ep; > > >>>> + bool sd_fwnode_is_ep; > > >>>> + const char *name; > > >>>> + > > >>>> + /* > > >>>> + * Both the subdev and the async subdev can provide either an endpoint > > >>>> + * fwnode or a device fwnode. Start with the simple case of direct > > >>>> + * fwnode matching. > > >>>> + */ > > >>>> + if (sd->fwnode == asd->match.fwnode) > > >>>> + return true; > > >>>> + > > >>>> + /* > > >>>> + * Otherwise, check if the sd fwnode and the asd fwnode refer to an > > >>>> + * endpoint or a device. If they're of the same type, there's no match. > > >>>> + */ > > >>>> + name = fwnode_get_name(sd->fwnode); > > >>>> + sd_fwnode_is_ep = name && strstarts(name, "endpoint"); > > >>>> + name = fwnode_get_name(asd->match.fwnode); > > >>>> + asd_fwnode_is_ep = name && strstarts(name, "endpoint"); > > >>> > > >>> Apart from the fact that you're parsing graph node names here, this looks > > >>> good. > > > > > > And why is that an issue btw ? the ACPI fwnode ops seem to provide a > > > .get_name() operation, would it return the ACPI bus ID here ? > > > > I'd really prefer not to do graph parsing outside the main parser(s), OF, > > ACPI and property frameworks. > > > > Just for an example, the v4l2_fwnode_link_parse() was broken for ACPI for a > > long time just because it did not use the graph parsing functions, but > > implemented graph parsing on its own. > > > > >>> How about checking instead that calling > > >>> fwnode_graph_get_remote_endpoint(fwnode_graph_get_remote_endpoint()) yields > > >>> the same node? That would ensure you're dealing with endpoint nodes without > > >>> explicitly parsing the graph in any way. > > >> > > >> Would it be simpler to check for the presence of an endpoint property ? > > > > There's no endpoint property, apart from an old ACPI definition. > > There isn't ? How does it work on ACPI then ? > acpi_graph_get_remote_endpoint() starts with > > ret = acpi_node_get_property_reference(__fwnode, "remote-endpoint", 0, > &args); The remote-endpoint property is used in ACPI, too, yes. But the question was about a property named "endpoint". > > > There are differences in the implementations and this is not the best place > > to try to take them all into account. > > OK, but in that case I think we need an fwnode_graph_is_endpoint(). Thinking about this --- could you check fwnode_graph_get_remote_endpoint() returns non-NULL, and then put the remote? That would be more simple as you are only interested in knowing you're dealing with an endpoint. I don't object having a little helper for this though. -- Regards, Sakari Ailus