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

Re: If you want to add a platform-specific quirk to a linux driver, make sure it's supported by Wind

[mjg59]

Which hardware are you thinking of that isn't?

Re: If you want to add a platform-specific quirk to a linux driver, make sure it's supported by Wind

[(Anonymous)]

Anything that doesn't make sense on x86. Various SOCs, for example.