[PATCH v11 4/4] G45 TWI: remove open drain setting for twi function gpios

[Voss, Nikolaus]

Hi Ludovic,

ludovic.desroches wrote on Monday, August 27, 2012 12:25 PM:
> Le 11/08/2011 12:11 PM, Nikolaus Voss a écrit :
>> The G45 datasheets explicitly states that setting the open drain property
>> on peripheral function gpios is not allowed. (How about other A91 chips?)
>
> Did you remove open drain because you had some issues or because you
> had  seen it into datasheet?
> 
> I tried with and without open drain. The behavior was the same. Looking
> to the G45 datasheet, I didn't see that the open drain property is not
> allowed on peripheral function gpios:
> 
> 'The Multi Drive can be selected whether the I/O line
> is controlled by the PIO controller or assigned to a peripheral function.'
> 
> The datasheet should have been updated or there is another place where
> it is mentioned that open drain property is not allowed in this case.

well, it didn't work on my G45. I found the following note in the
TWI chapter 31.6.1 of the G45 datasheet:
"The user must not program TWD and TWCK as open-drain.
It is already done by the hardware."

After removing the open-drain setting, it worked.

Regards,
Nikolaus