kernel-libre (hopefully 100% Free) for Fedora 8 and rawhide

[Michael C]

Alexandre Oliva wrote:
> Hi, Hans,
>
> On Mar 29, 2008, Hans de Goede <j.w.r.degoede at hhs.nl> wrote:
>
>   
>>> USB_SN9C102 - USB SN9C1xx PC Camera Controller support
>>>       
>
>   
>> Thats a fall positive there are a few hex coded tables in there, but
>> those are either:
>>     
>
>   
>> 1) color curve lookup tables
>>     
>
> I'm not smart enough to understand what "color curve lookup table"
> means.  Are the comments surrounding the code and published
> information available for this decide sufficient for someone
> relatively familiar with this topic to figure out what the numbers
> mean and to, say, fix the tables such that they work for a lightly
> defective camera that encodes colors incorrectly?
>
>   
>> 2) A standard jpg file format header which gets added in front of the raw jpeg
>>    data returned by the cam
>>     
>
> I think this is probably fine, indeed, if there's a comment explaining
> this.
>
>   
>> 3) register initialization tables consisting of { reg_addr, value } pairs
>>     
>
> Now this could be a problem or not.
>
> I've seen a number of drivers that profusely document the meaning of
> each register and how it's to be used, such that someone can really
> make sense out of it.  This is a great thing to have.
>
> Other drivers simply refer to published specifications that describe
> their meanings.
>
> I'd guess that in others, developers didn't mean to deny information,
> and they were just too lazy to provide all the information, or they
> figured things out by themselves without consulting any documentation
> whatsoever.  This could be defended as something other than trying to
> stop others from having freedom #1, although adding documentation for
> these cases would certainly add freedom.
>
> Unfortunately, in other cases, developers were under restrictions
> imposed by NDAs, or by copyrights or availability of the documentation
> they might have wanted to copy or refer to.  For these cases, someone
> is indeed hurting freedom #1, even if it's not the developer.
>
> It's hard to tell one case from the other just by looking at the
> code.  Sometimes you have to ask the developers, or the vendors of the
> part the code is for.
>
> You generally get one of these outcomes to a question such as 'Hey,
> I'm trying to tweak this code, but I can't figure out these numbers.
> Help?' is:
>
> (non-Free IMHO):
>
> - Sorry, I can't help you, I'm under an NDA
>
> - Sorry, I don't understand them myself.  The vendor just said this
> is what I should use.
>
> - Sorry, I don't understand them myself.  I just copied them from the
> Windows driver.
>
> (non-sure IMHO :-)
>
> - Sorry, I don't understand them myself.  After random trial and error
> and some investigation of the behavior of the component while it
> interacted with existing software, I got these numbers and they seem
> to work for me.
>
> (Free IMHO):
>
> - Sorry, I should have referred to the documentation, it's publicly
> available at http://...
>
> - Sorry, I didn't have time to document my findings.  Here are the
> notes I took while investigating the device.
>
> - Sorry, I didn't have time or permission to copy the entire
> documentation, but I'd be happy to send you a copy of the small
> portion that explains these numbers in case you'd like to add
> documentation to the code.
>
>   
>> I happen to know this driver quite well, which triggered me, but
>> chances are quite big that you've many more false positives.
>>     
>
> If you can help document the sequences of numbers that you can
> understand in there, this would be a great improvement.  Then, we'd
> have fewer doubts on whether that portion of source code is Free
> Software or not.  Without the documentation, in Jeff's position and
> given his commitment, I think he's taking a correct conservative
> position of leaving it out.
>
>   
Alexandre,

Isn't the logic of your position (when carried through to its necessary 
conclusion) that the *only* devices actually worthy of support by your 
kernel would be instances of free hardware, i.e. hardware wholly 
unencumbered by NDAs and patents (and thus, probably, the entire 
apparatus of bourgeois property relations)?

Best wishes,

Michael