Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
Date:   Tue, 25 Jun 2019 16:20:31 +0200
From:   Daniel Vetter <daniel@ffwll.ch>
To:     Russell King - ARM Linux admin <linux@armlinux.org.uk>
Cc:     Daniel Vetter <daniel@ffwll.ch>,
        Emil Velikov <emil.velikov@collabora.com>,
        linux-arm-kernel@lists.infradead.org,
        linux-samsung-soc@vger.kernel.org,
        Joonyoung Shim <jy0922.shim@samsung.com>,
        Maxime Ripard <maxime.ripard@bootlin.com>,
        Maarten Lankhorst <maarten.lankhorst@linux.intel.com>,
        Seung-Woo Kim <sw0312.kim@samsung.com>,
        Krzysztof Kozlowski <krzk@kernel.org>,
        Andrzej Pietrasiewicz <andrzej.p@collabora.com>,
        Inki Dae <inki.dae@samsung.com>,
        David Airlie <airlied@linux.ie>,
        Kyungmin Park <kyungmin.park@samsung.com>,
        Kukjin Kim <kgene@kernel.org>, dri-devel@lists.freedesktop.org,
        kernel@collabora.com, Sean Paul <sean@poorly.run>,
        linux-kernel@vger.kernel.org, m.szyprowski@samsung.com
Subject: Re: [PATCH 0/2] Associate ddc adapters with connectors
Message-ID: <20190625142031.GV12905@phenom.ffwll.local>
Mail-Followup-To: Russell King - ARM Linux admin <linux@armlinux.org.uk>,
        Emil Velikov <emil.velikov@collabora.com>,
        linux-arm-kernel@lists.infradead.org,
        linux-samsung-soc@vger.kernel.org,
        Joonyoung Shim <jy0922.shim@samsung.com>,
        Maxime Ripard <maxime.ripard@bootlin.com>,
        Maarten Lankhorst <maarten.lankhorst@linux.intel.com>,
        Seung-Woo Kim <sw0312.kim@samsung.com>,
        Krzysztof Kozlowski <krzk@kernel.org>,
        Andrzej Pietrasiewicz <andrzej.p@collabora.com>,
        Inki Dae <inki.dae@samsung.com>, David Airlie <airlied@linux.ie>,
        Kyungmin Park <kyungmin.park@samsung.com>,
        Kukjin Kim <kgene@kernel.org>, dri-devel@lists.freedesktop.org,
        kernel@collabora.com, Sean Paul <sean@poorly.run>,
        linux-kernel@vger.kernel.org, m.szyprowski@samsung.com
References: <cover.1561452052.git.andrzej.p@collabora.com>
 <20190625100351.52ddptvb2gizaepi@shell.armlinux.org.uk>
 <817ccfba-754c-6a28-8d75-63f70605fd43@collabora.com>
 <20190625133639.GA16031@arch-x1c3>
 <20190625140755.GT12905@phenom.ffwll.local>
 <20190625141032.5jiy2oekb3olaejd@shell.armlinux.org.uk>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <20190625141032.5jiy2oekb3olaejd@shell.armlinux.org.uk>
User-Agent: Mutt/1.10.1 (2018-07-13)
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

On Tue, Jun 25, 2019 at 03:10:32PM +0100, Russell King - ARM Linux admin wrote:
> On Tue, Jun 25, 2019 at 04:07:55PM +0200, Daniel Vetter wrote:
> > Otherwise I like this. Biggest problem I'm seeing here is rolling this out
> > everywhere, this is a lot of work. And without widespread adoptions it's
> > not terribly useful for userspace.
> 
> There will be cases where it's not possible, because the I2C bus is
> hidden behind a chip that doesn't give you direct access to the DDC
> bus.

Oh sure, plus lots of connectors where there's just not ddc bus at all.
But if we only roll this out for a handful of drivers it's also not great,
that's what I meant. Looking at

$ git grep drm_do_get_edid

there's only very few drivers where the ddc bus is hidden. There's a lot
more where it's not, and I think a big series to tackle those would serve
extremely well to make a case for this sysfs link.
-Daniel
-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch