Re: [Xenomai] Cross-compiling RTDM driver errors

[Stefan Videv <videvstefan@gmail.com>]

On 11/05/2012 06:50 PM, Gilles Chanteperdrix wrote:
> On 11/05/2012 07:00 PM, Stefan Videv wrote:
>
>> On 11/05/2012 05:33 PM, Stefan Videv wrote:
>>> On 11/05/2012 05:19 PM, Stefan Videv wrote:
>>>> On 11/05/2012 05:13 PM, Stefan Videv wrote:
>>>>> Hi,
>>>>>
>>>>> I am trying to cross compile a driver that I wrote which is very
>>>>> similar to the one provided in the examples (tut02-skeleton-drv).
>>>>> I've basically changed the write function to do what I am interested
>>>>> in doing, everything else is the same (however I am not providing a
>>>>> read function).
>>>>>
>>>>> During compilation I get the following error:
>>>>>
>>>>> FATAL: modpost: GPL-incompatible module vlcTxDriver.ko uses GPL-only
>>>>> symbol 'rtdm_dev_unregister'
>>>>>
>>>>> What's that supposed to mean, and how do you get around it?
>>>> I answered my own question just now -- I've forgotten to define the
>>>> module licence correctly. Having done that I end up with some
>>>> undefined symbols, just like when trying to compile the POSIX examples.
>>>>
>>>> Here's what I get:
>>>>
>>>> WARNING: "pse51_shm_close" [/home/stefan/VLCTxDriver/vlcTxDriver.ko]
>>>> undefined!
>>>> WARNING: "munmap" [/home/stefan/VLCTxDriver/vlcTxDriver.ko] undefined!
>>>> WARNING: "mmap" [/home/stefan/VLCTxDriver/vlcTxDriver.ko] undefined!
>>>> WARNING: "open" [/home/stefan/VLCTxDriver/vlcTxDriver.ko] undefined!
>>>>
>>>> Any help is appreciated! Thanks!
>>> I've somewhat answered my questions again:
>>>
>>> http://www.xenomai.org/pipermail/xenomai-help/2011-12/msg00014.html
>>>
>>> However, I still do not understand how do you go about enabling these
>>> features (i.e. what to enable when configuring my kernel).
>> I've enabled shared memory support from the POSIX options for Xenomai.
>> That takes care of the first 3 warnings.
>>
>> However, I am still having the last one. I am trying to use this
>> particular open() function:
>>
>> http://pubs.opengroup.org/onlinepubs/000095399/functions/open.html
>>
>> to be able to write to /dev/mem
>
> You do not write to /dev/mem in a kernel module. You use ioremap.
>
Great point :) Everything works now (well apart from the fact that I am 
not sure I am writing to the correct registers when using ioremap and 
iowrite, but that's outside the scope of this mailing list :) ).

Thanks!

-- Stefan