From mboxrd@z Thu Jan 1 00:00:00 1970 From: bsdimp@gmail.com (Warner Losh) Date: Fri, 28 Feb 2014 09:28:22 -0700 Subject: [PATCH 3/9] Doc/DT: Add DT binding documentation for DVI Connector In-Reply-To: <20140228162327.GT21483@n2100.arm.linux.org.uk> References: <1393590016-9361-1-git-send-email-tomi.valkeinen@ti.com> <1393590016-9361-4-git-send-email-tomi.valkeinen@ti.com> <20140228155937.GQ21483@n2100.arm.linux.org.uk> <5310B567.7040605@ti.com> <20140228162327.GT21483@n2100.arm.linux.org.uk> Message-ID: To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Feb 28, 2014, at 9:23 AM, Russell King - ARM Linux wrote: > On Fri, Feb 28, 2014 at 06:12:23PM +0200, Tomi Valkeinen wrote: >> On 28/02/14 17:59, Russell King - ARM Linux wrote: >> >>>> +dvi0: connector at 0 { >>>> + compatible = "dvi-connector"; >>>> + label = "dvi"; >>>> + >>>> + i2c-bus = <&i2c3>; >>>> + >>>> + dvi_connector_in: endpoint { >>>> + remote-endpoint = <&tfp410_out>; >>>> + }; >>>> +}; >>> >>> This looks far too simplistic. There are different classes of DVI >>> connector - there is: >>> >>> DVI A - analogue only >>> DVI D - digital only (single and dual link) >>> DVI I - both (single and dual digital link) >>> >>> DRM at least makes a distinction between these three classes, and this >>> disctinction is part of the user API. How would a display system know >>> which kind of DVI connector is wired up on the board from this DT >>> description? >> >> Yes, I think that's a valid change. But do we also need to specify >> single/dual link, in addition to the three types? > > I would argue that as it's a difference in physical hardware, then it > should be described in DT, even if we don't use it. The reasoning is > that although we may not use it today, we may need to use it in the > future, and as we're describing what the hardware actually is - and > even in this case what pins may be present or missing on the connector, > it's unlikely to be problematical (the only problem is when someone > omits it...) And the ?we? that uses the DT files is larger than just the Linux, and one of those systems may use it. Warner