License for the libi2c

License for the libi2c

[Mihai Buha]

Hello list,
 
I have just read the Plans for I2C Tools 4 and I saw that Jean (khali) intends to release the new libi2c under the LGPL. I wonder, however, if that is legally possible, since the functions in i2c-dev.h are subject to the GPL, and only the original implementor is allowed to change the licensing terms if I understand the GPL correctly (the file was originally added in the i2c-tools repository by Kyo:sti (kmalkki), but he may have copied the functions from somewhere else).
 
The only ways I see to change the licensing are the following:
1) GPL'd code can be relicensed as LGPL by any user (I don't think it's possible);
2) Kyo:sti wrote the code, so he should give his written permission to relicense;
3) Kyo:sti copied the code, so the original author should be tracked down and asked to give his written permission to relicense.
This process should be performed for all the code that is to be relicensed as LGPL.
 
What do you think?
 
Disclaimer: IANAL.
 
Thanks,
Mihai Buha

Newbie: accessing i2c features through kernel functions

[CF]

Hello,

I'm requesting help. I am currently successfully using i2c-dev module.
But i'm unable to drive i2c busses from kernel space as i'd do from
userspace (with the use of open, read, write, ioctl functions). I can't
logically acces glibc.

Can somebody point me how i could do from kernel space ? Given all is
actually working (precisely, i can recompile i2c-dev, and i write an
userspace code to manage my i2c slave device).

My goal is to keep i2c-dev suitable initialisation, then wrap some i2c
commands into the module to expose userspace a simplified API, with all
my device commands. I must do this in kernel space, else i'd have done
what i'm able to do: create an userspace lib relying on /dev/i2c-x.

Thank you. Once again i apologize if this is not the place but i'm
unable to find suitable ML for this kind of request.

Re: Newbie: accessing i2c features through kernel functions

[Anatolij Gustschin]

On Fri, 31 May 2013 11:49:41 +0200
CF <cfoissac-GANU6spQydw@public.gmane.org> wrote:

> I'm requesting help. I am currently successfully using i2c-dev module.
> But i'm unable to drive i2c busses from kernel space as i'd do from
> userspace (with the use of open, read, write, ioctl functions). I can't
> logically acces glibc.
> 
> Can somebody point me how i could do from kernel space ? 

you need to get the I2C adapter for your bus using i2c_get_adapter()
and then send the I2C messages by i2c_transfer().

Anatolij

Re: Newbie: accessing i2c features through kernel functions

[CF]

Le 31/05/2013 16:56, Anatolij Gustschin a écrit :
> On Fri, 31 May 2013 11:49:41 +0200
> CF <cfoissac-GANU6spQydw@public.gmane.org> wrote:
>
>> I'm requesting help. I am currently successfully using i2c-dev module.
>> But i'm unable to drive i2c busses from kernel space as i'd do from
>> userspace (with the use of open, read, write, ioctl functions). I can't
>> logically acces glibc.
>>
>> Can somebody point me how i could do from kernel space ?
> you need to get the I2C adapter for your bus using i2c_get_adapter()
> and then send the I2C messages by i2c_transfer().
>
> Anatolij
>
Thank you for your help. I'll feedback as soon as i got something working.
CF

Re: Newbie: accessing i2c features through kernel functions

[CF]

Le 31/05/2013 16:56, Anatolij Gustschin a écrit :
> On Fri, 31 May 2013 11:49:41 +0200
> CF <cfoissac-GANU6spQydw@public.gmane.org> wrote:
>
>> I'm requesting help. I am currently successfully using i2c-dev module.
>> But i'm unable to drive i2c busses from kernel space as i'd do from
>> userspace (with the use of open, read, write, ioctl functions). I can't
>> logically acces glibc.
>>
>> Can somebody point me how i could do from kernel space ?
> you need to get the I2C adapter for your bus using i2c_get_adapter()
> and then send the I2C messages by i2c_transfer().
>
> Anatolij
>
It works flawlessly. I could directly drive a device attached to my i2c 
bus simply by wrapping i2c_tranfer() and some i2c_msg messages, thus 
expose w/e functions i need to propose a reduced instruction set.

I also learned how works fops structure, to retrieve the equivalent of 
open/read/write/ioctl 's GLIBC in kernel space. Although i don't use it 
for my need, quick tests worked nicely with them.

I'll perhaps dig how to work with others structures (in example i don't 
really see how i2c_client works), and i certainly also need to 
understand the differences between various algorithms.

Thank you !