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out of tree

Posted Aug 5, 2009 18:05 UTC (Wed) by mikov (subscriber, #33179)
In reply to: out of tree by farnz
Parent article: A tempest in a tty pot

It is a problem in Windows, too; for example, very few graphics card drivers support Windows native screen rotation in XP - you need to use a vendor utility instead.

I don't want to defend Windows, but IIRC that is technically wrong. Unless I am mistaken, XP does not support native screen rotation. It was introduced in Vista.

I do agree with your general point that you can't rely on the vendors to "do the right" thing. Vendors do suck. I have seen really really horrible disgusting things working with closed source drivers. But this is an impossible battle. You can't require all developers for your OS to be perfect. People will do whatever they want to do. The best you can do is give them tools encouraging them in the right direction. Plus, hopefully GPL will shame them into better code.

Look at Google Android. They are basically doing whatever they want with the kernel and not bothering to submit anything back.

They didn't keep the graphics driver API the same from NT 3.1 to Windows XP. Newer OSes cannot run graphics cards using older drivers, pure and simple. No different to Linux, in that respect.

I am sorry but that is not quite true either. In a previous life I used to do Windows kernel development, and graphics drivers specifically. I have ported drivers from NT4 to W2K and WXP. The API remained backwards compatible and even binary compatible.

In NT4 they did a fundamental architectural change by moving the drivers into the kernel, but the source level API remained compatible with NT 3.51.

And note that vendors do need to bring the Linux community on board - my employer alone buys a significant number of TV capture cards a month, on condition that they are supported under Linux. We pay a slight premium to buy Hauppauge cards because of the Linux support; other vendors are £5/card cheaper, but cost huge amounts of money in expensive developer time keeping the card going.

I don't quite follow. Can you please clarify a bit? Why do the other cards need huge amounts of money? Also, you are saying that Hauppauge is more expensive because it has to support Linux. So, how is that a good thing?

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out of tree

Posted Aug 5, 2009 18:15 UTC (Wed) by johnflux (subscriber, #58833) [Link]

> I don't quite follow. Can you please clarify a bit? Why do the other cards need huge amounts of money? Also, you are saying that Hauppauge is more expensive because it has to support Linux. So, how is that a good thing?

I think his point was that his company was willing to pay extra just for linux support. So Hauppauge was able to charge more money, and still get his custom. Whereas the companies that didn't support Linux didn't get his business.

From a business point of view, if the money that a company loses because of their lack of linux support is greater than the cost of opening the specs or writing the drivers, then the company should write Linux drivers. The poster was providing anecdotal evidence to indicate that they believe that this is the case for some (most?) companies.

On a personal note, I think companies perceive the cost of opening their drivers to be far higher than it really is.

out of tree

Posted Aug 5, 2009 18:45 UTC (Wed) by farnz (guest, #17727) [Link]

Hauppauge cards tend to work out of the box with a recent enough kernel; when they don't, Hauppauge employees are happy to help you make the cards work. Other vendors cards require developer time to make work, and attempts to get the vendor to help tend to be fruitless (they have their own out of tree driver that doesn't work well, due to reinvention of interfaces, and don't understand why you won't simply rewrite your userspace to match their driver).

Developer time is hugely expensive, as we don't have much to spare; given the choice between a small amount of extra money per card (to the vendor), or developer time, we'd rather pay. If you're a vendor, looking to expand, this is a market, and it has money to spend on you.