When to add a platform-specific quirk to a Linux driver

[mjg59]

If you're tempted to add a platform-specific quirk to a Linux driver, pause and do the following:

1. Check whether the platform works correctly with the generic Windows driver for the hardware in question. If it requires a platform-specific driver rather than the generic one, adding a quirk is probably ok.
   
2. If the generic Windows driver works, check whether there's any evidence of platform-specific code in the Windows driver. This will typically be in the .inf file, but occasionally you'll want to run strings against the Windows driver and see whether any functions or strings match the platform in question. If there's evidence of special-casing in the generic Windows driver, adding a quirk is probably ok
   
3. If the generic Windows driver works and doesn't appear to have any platform-specific special casing, don't add a quirk. You'll plausibly fix the machine you care about, but you won't fix any others that have the same behaviour. Even worse, if someone does eventually fix the problem properly, there's a risk that your special-casing will now break your system.

The moral to this story is: if you think adding a quirk is the right solution, you're almost certainly wrong.

Comments

How can this be legally done while accepting both copyright and contract law?

[(Anonymous)]

At least I find the terms of use for Windows unacceptable, and thus can not enter the contract Microsoft present to be able to legally use Windows. How are those of use that find terms for example prohibiting reverse engineering to follow your advice? I am aware of the alternative to ignore the terms and just press 'accept' on anything presented, but that seem to me to be the same as ignoring both copyright and contract law, which I also find unacceptable.

Re: How can this be legally done while accepting both copyright and contract law?

[(Anonymous)]

I'd say it'd be a bit of a stretch to declare what's described here as "reverse engineering". Not implausible, but a stretch