Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S938785AbcKWPMj (ORCPT ); Wed, 23 Nov 2016 10:12:39 -0500 Received: from nblzone-211-213.nblnetworks.fi ([83.145.211.213]:59592 "EHLO hillosipuli.retiisi.org.uk" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S935760AbcKWPMh (ORCPT ); Wed, 23 Nov 2016 10:12:37 -0500 Date: Wed, 23 Nov 2016 17:10:42 +0200 From: Sakari Ailus To: Javi Merino Cc: linux-media@vger.kernel.org, linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, Pantelis Antoniou , Mauro Carvalho Chehab , Javier Martinez Canillas , Sakari Ailus Subject: Re: [PATCH] v4l: async: make v4l2 coexists with devicetree nodes in a dt overlay Message-ID: <20161123151042.GD16630@valkosipuli.retiisi.org.uk> References: <1479895797-7946-1-git-send-email-javi.merino@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1479895797-7946-1-git-send-email-javi.merino@kernel.org> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2155 Lines: 55 Hi Javi, On Wed, Nov 23, 2016 at 10:09:57AM +0000, Javi Merino wrote: > In asd's configured with V4L2_ASYNC_MATCH_OF, if the v4l2 subdev is in > a devicetree overlay, its of_node pointer will be different each time > the overlay is applied. We are not interested in matching the > pointer, what we want to match is that the path is the one we are > expecting. Change to use of_node_cmp() so that we continue matching > after the overlay has been removed and reapplied. > > Cc: Mauro Carvalho Chehab > Cc: Javier Martinez Canillas > Cc: Sakari Ailus > Signed-off-by: Javi Merino > --- > Hi, > > I feel it is a bit of a hack, but I couldn't think of anything better. > I'm ccing devicetree@ and Pantelis because there may be a simpler > solution. First I have to admit that I'm not an expert when it comes to DT overlays. That said, my understanding is that the sub-device and the async sub-device are supposed to point to the exactly same DT node. I wonder if there's actually anything wrong in the current code. If the overlay has changed between probing the driver for the async notifier and the async sub-device, there should be no match here, should there? The two nodes actually point to a node in a different overlay in that case. > > drivers/media/v4l2-core/v4l2-async.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/drivers/media/v4l2-core/v4l2-async.c b/drivers/media/v4l2-core/v4l2-async.c > index 5bada20..d33a17c 100644 > --- a/drivers/media/v4l2-core/v4l2-async.c > +++ b/drivers/media/v4l2-core/v4l2-async.c > @@ -42,7 +42,8 @@ static bool match_devname(struct v4l2_subdev *sd, > > static bool match_of(struct v4l2_subdev *sd, struct v4l2_async_subdev *asd) > { > - return sd->of_node == asd->match.of.node; > + return !of_node_cmp(of_node_full_name(sd->of_node), > + of_node_full_name(asd->match.of.node)); > } > > static bool match_custom(struct v4l2_subdev *sd, struct v4l2_async_subdev *asd) -- Kind regards, Sakari Ailus e-mail: sakari.ailus@iki.fi XMPP: sailus@retiisi.org.uk