Re: Newbie: accessing i2c features through kernel functions

[CF <cfoissac-GANU6spQydw@public.gmane.org>]

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 !