Subject: Re: [PATCH] i2c-qoriq: modified compatibility for correct prescaler

From: Valentin Longchamp <[email-masked]>
Date: Fri, 14 Nov 2014 08:43:01 +0100

On 11/13/2014 01:34 AM, Wolfram Sang wrote:
> 
>> If we wanted to be on the safe side and strict (since we are not sure that the
>> hardware is 100% compatible), we maybe should add a fsl,qoriq-i2c compatible to
>> the driver that does the same as mpc8543-i2c.
> 
> Or you leave the driver as is and use both compatibles:
> 
> compatible = "fsl,qoriq-i2c", "fsl,mpc8543-i2c", "fsl-i2c";
> 
> ?
> 

I like Scott's proposition to add the prescaler in the device tree more. From
the hardware description point of view, it makes more sense: the devices are all
just fsl-i2c, with a different prescaler. I just quote it below as a reminder.

> 
> If we're going to change the device tree I'd rather just add a property
> to say what the prescaler is.

 We would however, leave the boards' device trees that use things like
"fsl,mpc8543-i2c" as is and introduce the prescaler for the others requiring it.

Now the drawback is that the driver would require a change, to parse this
prescaler new prescaler property. Would this be OK from your point of view
Wolfram ? If yes, I will send the patches for it.

Valentin