From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752502AbdJKXOn (ORCPT ); Wed, 11 Oct 2017 19:14:43 -0400 Received: from mail-pf0-f196.google.com ([209.85.192.196]:35882 "EHLO mail-pf0-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751694AbdJKXOj (ORCPT ); Wed, 11 Oct 2017 19:14:39 -0400 X-Google-Smtp-Source: AOwi7QDWuAfLgmd7d9ZZb/IDY6nKtkO04RILtaxWs+HdRmYqizv/OIITYueXusIlzB+KaZujnlB3tA== Subject: Re: [PATCH] media: staging/imx: do not return error in link_notify for unknown sources To: Russell King - ARM Linux Cc: Philipp Zabel , Mauro Carvalho Chehab , Greg Kroah-Hartman , linux-media@vger.kernel.org, devel@driverdev.osuosl.org, linux-kernel@vger.kernel.org, Steve Longerbeam References: <1507057753-31808-1-git-send-email-steve_longerbeam@mentor.com> <20171011214906.GX20805@n2100.armlinux.org.uk> <87b48a34-4beb-eb21-3361-28f6edb6d73c@gmail.com> <20171011230633.GZ20805@n2100.armlinux.org.uk> From: Steve Longerbeam Message-ID: Date: Wed, 11 Oct 2017 16:14:36 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.3.0 MIME-Version: 1.0 In-Reply-To: <20171011230633.GZ20805@n2100.armlinux.org.uk> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 10/11/2017 04:06 PM, Russell King - ARM Linux wrote: > On Wed, Oct 11, 2017 at 03:14:26PM -0700, Steve Longerbeam wrote: >> >> On 10/11/2017 02:49 PM, Russell King - ARM Linux wrote: >>> On Tue, Oct 03, 2017 at 12:09:13PM -0700, Steve Longerbeam wrote: >>>> imx_media_link_notify() should not return error if the source subdevice >>>> is not recognized by imx-media, that isn't an error. If the subdev has >>>> controls they will be inherited starting from a known subdev. >>> What does "a known subdev" mean? >> It refers to the previous sentence, "not recognized by imx-media". A >> subdev that was not registered via async registration and so not in >> imx-media's async subdev list. I could elaborate in the commit message >> but it seems fairly obvious to me. > I don't think it's obvious, and I suspect you won't think it's obvious > in years to come (I talk from experience of some commentry I've added > in the past.) > > Now, isn't it true that for a subdev to be part of a media device, it > has to be registered, and if it's part of a media device that is made > up of lots of different drivers, it has to use the async registration > code? So, is it not also true that any subdev that is part of a > media device, it will be "known"? > > Under what circumstances could a subdev be part of a media device but > not be "known" ? > > Now, if you mean "known" to be equivalent with "recognised by > imx-media" then, as I've pointed out several times already, that > statement is FALSE. I'm not sure how many times I'm going to have to > state this fact. Let me re-iterate again. On my imx219 driver, I > have two subdevs. Both subdevs have controls attached. The pixel > subdev is not "recognised" by imx-media, and without a modification > like my or your patch, it fails. However, with the modification, > this "unrecognised" subdev _STILL_ has it's controls visible through > imx-media. Well that's true, the controls for your pixel subdev (which was not registered via async) still are visible to imx-media, so in that sense the subdev is "known" to imx-media. > > Hence, I believe your comment in the code and your commit message > are misleading and wrong. Ok you convinced me, I'll fix the code comment and commit message. Steve