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=-8.3 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,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 C5CB4C5ACD7 for ; Wed, 18 Mar 2020 11:22:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9219620770 for ; Wed, 18 Mar 2020 11:22:24 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=ideasonboard.com header.i=@ideasonboard.com header.b="YMaY9dt9" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727443AbgCRLWY (ORCPT ); Wed, 18 Mar 2020 07:22:24 -0400 Received: from perceval.ideasonboard.com ([213.167.242.64]:44584 "EHLO perceval.ideasonboard.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726486AbgCRLWX (ORCPT ); Wed, 18 Mar 2020 07:22:23 -0400 Received: from pendragon.ideasonboard.com (81-175-216-236.bb.dnainternet.fi [81.175.216.236]) by perceval.ideasonboard.com (Postfix) with ESMTPSA id 517A3F9; Wed, 18 Mar 2020 12:22:21 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com; s=mail; t=1584530541; bh=1ihwVuUKLCioC7VH4pTXgg5vACyhvYbBxErmRPr0VVI=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=YMaY9dt9zv5a/Rl78xUEtC3k4L7RE0xe/8KUk/wB0GbNFkFMZJ3+pu4gLa+HvYiwS FAXhwzyJRp06AvzrqXWhjSbHMB6ZopCKVFTyNfw9xM1U42LHK8tkohl+pNpMwT3I2W JNWjs9bkh0fRtm9y4rQFhnEMk2r8XDcXanUod3rk= Date: Wed, 18 Mar 2020 13:22:16 +0200 From: Laurent Pinchart To: Sakari Ailus Cc: Laurent Pinchart , linux-media@vger.kernel.org, Jacopo Mondi , Niklas =?utf-8?Q?S=C3=B6derlund?= , Kieran Bingham , Lad Prabhakar Subject: Re: [PATCH] media: v4l2-async: Accept endpoints and devices for fwnode matching Message-ID: <20200318112216.GC4733@pendragon.ideasonboard.com> 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> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20200318075225.GA2101@mara.localdomain> 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 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); > 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(). -- Regards, Laurent Pinchart