[ZiiS]

Someone without contracts with the HDMI Forum can probably release a working driver. However, AMD obviously needs to license the logo for their GPU boxes and their legal team have decided this prevents them releasing any source code based on the private specification regardless of what the code is called.

[fps_doug]

> AMD obviously needs to license the logo for their GPU boxes

This poses an interesting question, maybe some of the hobby-lawyers on HN like to chime in and post heir theories :o)

Let's assume they print that Logo on their box, call it HDMI in their Windows drivers, but don't do so in their Linux drivers, while it's still a spec-compliant implementation. Would that pose a potential legal problem, and if so why?

If it's the fact that they have access to the official HDMI 2.1 spec, implemented that, but call it something else, which I could imagine they forbid in some contract, would things change if some random hacker with too much time on their hands reversed the protocol by sniffing it, implementing it for the AMD driver (again without calling it HDMI)?

Too bad the HDMI forum doesn't feature an email address on their home page, I'd have loved to tell them what I think of them.

[megous]

You don't just sniff a 48Gbit/s protocol as a random hacker. That's not what happens in the real world. A real-time scope that could do that is in the $1mil dollar range.

At best a random hacker will reverse engineer the binary driver enough to make something work in some capacity.

[CuriousCosmic]

Yes you actually can. It's known that HDMI is TMDS and that the fastest frequency on any given pair is 680MHz and there are a total of 13 data pins (4 pairs + i2c + CEC pin + hot plug detect pin + reserved pin for some special features). A digital logic analyser that can sample at that rate over all 13 pins is going to cost less than a grand. If you stub in some hardware to convert the differential pairs back to a single hi/low signal and drop the optional features of the reserved pin, you can cut that down to 8 signals (or less if your analyzer has dedicated clock signal pins). A DSLogic U3Pro16 is 299usd and can sample 8 signals at 1GHz in buffer mode or 3 pins at 1GHz indefinitely in streaming mode.

If you know roughly what you are looking for, you can set triggers to start sampling when the event you care about starts, that's more than enough to be able to reverse engineer even the most intensive of the existing HDMI spec.

Given that a lot of these graphics cards cost substantially more than 300usd, it's not unreasonable to expect a logic analyzer capable of digesting HDMI to be within their price range.

[ZiiS]

A lot of those $1mil dollar scopes run Linux and connect to fast, high resolution displays; some of them are made by companies not always in love with US licensing.

[fps_doug]

Sure, but this is a hypothetical scenario, focusing on the legal aspects.

[megous]

Legal aspects of something that can never happen? Why?

Try legal aspects of reverse engineering a binary driver. That's more realistic.

[iforgotpassword]

But the question is not whether it's legal to reverse engineer a binary. The question is whether someone with no affiliation to neither the HDMI forum nor AMD could contribute the according code to the AMD driver which is part of the Linux Kernel, regarding legal implications.

Reverse engineering of binaries is pretty much a solved problem from the legal standpoint.

[fps_doug]

It's hypothetical. There is no difference between those two scenarios, we could also just assume the hacker pulled it out of their ass...

[megous]

Fine, but it's useless then.

[Pet_Ant]

I mean a $1M is crowd sourceable if there was a trustworthy person to do this.

[ZiiS]

There is a contract between AMD and HDMI Forum covering the licence to use the logo. We don't know the wording, and I am sure it is thousands of pages of dense legalise; but it can literally say: "We promise not release a Linux driver compatible with the spec.".

[mschuster91]

> Too bad the HDMI forum doesn't feature an email address on their home page, I'd have loved to tell them what I think of them.

They actually do at the bottom of [1].

[1] https://hdmiforum.org/about/

[luke-stanley]

Thanks, I emailed them: # Solutions for the growing open source user base "Hello, I am an AMD user, who uses Linux, and I currently use a small HDMI screen but I am looking to upgrade to a larger screen and I am concerned about the forum's decision to deny AMD's open source HDMI implementation. This decision has led to criticism of the entire HDMI enterprise as rent-seeking, and encourages non-trademarked implementations that weaken the HDMI brand. Linux is only growing in popularity, as people are tired of the advertising baked into Windows, and don't always want a Mac either, I highly suggest a re-think that looks at the rising popularity of open source with Linux, Android, Chrome and so on, to protect the HDMI brand.

Sincerely, Luke Stanley"

[rickdeckard]

Also, that someone without contracts would probably need to call it different than "HDMI", because the term itself is trademarked and only licensed to Members (like "Wi-Fi" and "Bluetooth").

So a different term would be needed (like "WLAN" or "BT" is used by non-members)

[sverhagen]

As much as we can talk about HDMI here, as it's a name in the public domain, wouldn't someone else be able to use that kind of speech to make a "HDMI-compatible" implementation? "IBM compatible" seemed to be a designation, in the day, that didn't run up against legal trouble?

Maybe that's what you already meant by "calling it different than".

[addandsubtract]

HDIY

[BigJ1211]

Could then just call it: HDMIY, no?

High Definition Make It Yourself

[missjellyfish]

Trademark law always hinges on the question if a reasonable consumer with reasonable knowledge could be expected to distinguish those trademarks or not.

HDMIY would most probably not fly, HDIY would probably.

not yet a lawyer, though.

edit: I'm also fairly certain that the HDMI forum would fight HDIY tooth and nail, so whoever goes public with that absolutely needs deep pockets.

[echoangle]

I am pretty sure that the term being a trademark doesnt stop me from mentioning it when describing compatibility. Do you think apple could sue me if i release a program and say "This software is compatible with macOS"? As long as I am not impersonating them, using the Logo etc., they probably can not stop me.

[Someone]

Of course they could sue you, and so could I. Neither of us would win, though. I because I don’t hold the trademark, they because they explicitly allow you to do that.

Like any big company, they have guidelines outlining permitted use. Apple’s page (https://www.apple.com/legal/intellectual-property/guidelines...) says:

“2. Compatibility: Developers may use Apple, Macintosh, iMac, or any other Apple word mark (but not the Apple Logo or other Apple-owned graphic symbol/logo) in a referential phrase on packaging or promotional/advertising materials to describe that the third party product is compatible with the referenced Apple product or technology, provided they comply with the following requirements.

a. The Apple word mark is not part of the product name.

b. The Apple word mark is used in a referential phrase such as “runs on,” “for use with,” “for,” or “compatible with.”

c. The Apple word mark appears less prominent than the product name.

d. The product is in fact compatible with, or otherwise works with, the referenced Apple product.

e. The reference to Apple does not create a sense of endorsement, sponsorship, or false association with Apple or Apple products or services.

f. The use does not show Apple or its products in a false or derogatory light.”

[echoangle]

Ok sure, they could sue me, but they would not win. Do you think they would win if they had not explicitely allowed that usage? I don't have a source but I am very sure that you can't stop someone from using your trademark, the trademark only protects the use in business, i.e. me selling a OS called "macOS". Just mentioning the name is no trademark infringement.

[hnfong]

I'm pretty sure your legal analysis here is overly-simplistic, but we don't need to get into that.

Going back to the original topic, if somebody is trying to release open source drivers for HDMI (or a protocol compatible with HDMI), obviously trademark infringement is a possibility since both are in the exact same business. So even if you're right (which I don't think so), your argument doesn't apply.

[echoangle]

Being in the same business does not make it trademark infringement. Ubuntu could also advertise "This OS can run software for Windows by using WINE" without infringing on Microsoft's trademark, because they aren't acting under the trademark. Trademarks exist so you can't sell your product under the established name of another company and profit from their reputation or ruin it by selling bad products. Just mentioning the name to state a fact is not forbidden. Just writing a driver and distributing it with the claim "HDMI-compatible" is not trademark infringement. They problem in OP's article is that AMD has a contract with the HDMI Forum.

[dgfitz]

I do know, for example, that sports talk radio shows aren’t allowed to use the term “Super Bowl”

[ysofunny]

i'm pretty sure apple would and could sue you if you do that.

but it really depends on how much attention you get

gotta keep an eye on the nintendo emulator lawsuit.... the war on general purpose computation carries on

[poizan42]

Saying "compatible with <trademark>" is if anything one of the best established examples of nominative use. Like PC-compatibles which IBM had no way of stopping. Apple could try to sue, but the case would get dismissed immediately.

[extraduder_ire]

Any time I've seen that on actual packaging, it does come along with "<trademark> is a registered trademark of <corporation>". Though usually those same boxes use official published logos from <corporation>.

[organsnyder]

Apple actually explicitly states that you may do this: https://www.apple.com/legal/intellectual-property/guidelines...

Though even if they didn't they wouldn't have a legal leg to stand on if they sued.

[salviati]

I checked and found this info from the Wi-Fi Alliance [0]:

> Select brands and logos are offered license free and intended to be used widely throughout the Wi-Fi ecosystem by Wi-Fi Alliance members, non-members, industry partners, media, and analysts to describe products, technology, network deployments, and operating system support.

It sounds to me like anyone could use the trademark "Wi-Fi", since it's listed in the freely available ones.

[0] https://www.wi-fi.org/who-we-are/our-brands

[rickdeckard]

> It sounds to me like anyone could use the trademark "Wi-Fi", since it's listed in the freely available ones.

Yes, to describe Wi-Fi as defined by the Wi-Fi Alliance, not to describe anything the Alliance does NOT consider compliant.

[aethertron]

Trademarks are there to protect consumers from dishonestly represented goods. If I buy some display tech marketed as "HDMI-compatible" but unlicensed, and it works with my other HDMI equipment (say, its maker reverse-engineered the HDMI spec), no one has been defrauded.

[franky47]

Call it IDMH, I don't mind, honestly.

[RicoElectrico]

Or IWCH ;-)

[franky47]

Took me a while to get it.

https://www.reddit.com/r/talesfromtechsupport/comments/5o67z...

[phkahler]

>> However, AMD obviously needs to license the logo for their GPU boxes...

It's not just that, it's about playing nice so they can have access to the next version of the spec if one comes along.