✧✦Catherine✦✧what does it mean for DisplayPort to be "open-source"
what is the source of DisplayPort
Gunnaris it the standard that says "DISTRIBUTION TO NON-MEMBERS IS PROHIBITED" on every page? is this what we call "open-source" now?
is it the technology that is patented by at least 10 companies (the full list isn't known) including Apple? is this "open-source"?
is it the compliance test suite and Verilog code that is available from VESA under an OSI-approved licensaahahahahahahaha I cannot do this anymore
*wipes tears* is it the lack of content protection, ensuring our lives will continue DRM-free?
*checks spec* no it just uses HDCP, exactly like HDMI
is it the DisplayPort logo and name, which can be used free of charge and without restrictions by anyone implementing the standard?
*checks VESA marketing guidelines* no, that's not it either!
so it turns out that DisplayPort is "open-source" because VESA (a consortium of multinational corporations) does not, as of present day, have a history of impeding some of the other multinational corporations from releasing some of the related code under an open-source license
that's a pretty weak definition of "open-source", folks
also if you call your HDMI port a "○○MI" port or whatever, the HDMI Forum can't go after you any more VESA can, go wild, everyone does this
(by the way, I think VESA being protective of the DP trademark is just about the only reasonable part of this; HDMI Forum should be able to do this too; that they can abuse this power is an unfortunate, currently unavoidable, side effect of the desirable ability to actually know if a thing you bought is mostly compatible with this other thing you have or not)
as pointed out by @azonenberg, getting the DisplayPort v1.0/v1.1a spec (the latter being released in 2008) does not require an NDA with VESA. it's still patent-encumbered, you still can't use their trademarked logo if you implement it but don't submit for compliance, it still includes HDCP by reference, but at least you can get the PDF
(as you can probably tell I have all the PDFs anyway, it's not really the obstacle to anything)
Samantaz Fox@whitequark @azonenberg I wish these kind of specs were all easily accessible and didn't require to register a billion accounts among stupid orgs. At least, the USB-IF org publishes everything for free!
Andrew Zonenberg@SamantazFox @whitequark 802.3 is freely downloadable although you do have to make an account to get it.
I love this, so I@whitequark this is the same line of thinking that leads to every cheap gadget from AliExpress having a “TF Card” slot
@jpm it is!
Thepi@whitequark So it's 'Open Source' in the same same sense that the baked beans in my pantry are 'Open Cans'.
Cysio 
@whitequark it's a low bar and HDMI still doesn't clear it
I mean, we can't really get something as good but also fully open source
Jason Petersen (he)@whitequark I thought they were threatening to do exactly that to AMD (or was that for HDMI?), who something something wanted to release an open-source implementation (I forget the details)?
@jason that was HDMI, yes
@whitequark ah! Phew, DisplayPort OSS dodged a bullet there
Ignas Kiela@whitequark FWIW VESA is more open with other specs of theirs (like DSC), so it's not like they haven't shown at least some appreciation towards opening up their stuff, it's just DP that's needlessly controlled.
Ölbaum@whitequark
I-IDIVII
I-IDIVII
Claudius@whitequark like the adafruit boards with their DVI ports. Which use an HDMI plug by accident ;-)
jubilee@whitequark Big Fucking Media Interface.
Farce Majeure@whitequark Agreed that it's a shoddy use of "open". OTOH VESA doesn't have the greatest history but I don't think they've ever stopped members from releasing open source implementations... @airlied might know better.
Dave Airlie@vathpela @whitequark
Original displayport spec was released to public, later versions not so much. But afaik vesa has never said we couldn't implement something in the Linux drivers.
Original displayport spec was released to public, later versions not so much. But afaik vesa has never said we couldn't implement something in the Linux drivers.
EvilKiru 🇮🇸 he/him@whitequark Although some VESA members release open source software, VESA itself is entirely corporate and has never committed to open-source at any level, from what I've read about them.
Ariadne Conill 🐰
@whitequark also, like, is displayport even really patent-free? or is this a “just trust me bro” situation?
@ariadne it's explicitly not; VESA will license some of the patents (there are too many to count manually, about a hundred listed in the v2.0 spec) to you under RAND terms
Clifton RoystonRAND, for those not in the know, usually means more or less “We won’t charge your tiny open source project *more* for the patent license fees than we charge a multi-billion international conglomerate.”
@CliftonR @whitequark MP3 patents were available under RAND terms, and yet many distributions avoided MP3 codecs until the patents expired. but i see the same people who were saying “MP3 bad!” also saying “DisplayPort fine!” and it’s just strange to me :)
(i understand from the context of a distribution it’s probably not a detail of concern, but then again you have firmware and training data and so on which get distributed by distributions and maybe those things are threatened by patents, actually?)
Billy O'Neal@ariadne @CliftonR @whitequark My understanding of the differences are:
1. the MP3 patents were asserted long after MP3 became a defacto standard, so the behavior was seen as predatory
Note that this is my recollection, if someone has hard data on the actual timelines here it would be nice.
2. DisplayPort has HDMI right next door as the example of the 'it can be worse program¹'. It's less 'we love everything about DisplayPort' and more 'we love DisplayPort in comparison to the other common standard, HDMI'.
Despair, Inc. - The Art of Demotivation: "Addressing Employee Complaints"
@whitequark right, that’s what i am getting at. i see people out there saying displayport is 100% free™️, and that just does not jive with my understanding of how VESA operates.
Niels Moseley@whitequark non-members of the human race?
Cwd o Seiber-ysbridion@whitequark distribution to non-members* is prohibited
* - of the human species,
Eunakria@alexandria @whitequark damn, I was really hoping to create a DisplayPort implementation with my cat but if they can't read the spec I guess those plans are dashed
@alexandria @whitequark (to be abundantly clear, I do recognize the actual meaning of the NDA clause and how it hurts independent implementers and I'm not trying to downplay this)
Diego Elio Pettenò@whitequark not arguing it being open source, but isn't the point you can get official chips such as mixers from e.g. TI without being members of the forum, unlike HDMI?
Maddie (MIGRATING SOON)@whitequark open source if it was decided by red hat
Wolf480pl@whitequark is this new in the latest revision or has DP spec always been like that?
Chris 
@whitequark I'd call that "source available".
Btw I don't know if DisplayPort is called open source, but it is at least royalty free?