[U-Boot] BayTrail I2C support

[Bin Meng]

Hi Stefan,

On Mon, Mar 14, 2016 at 8:30 PM, Stefan Roese <sr at denx.de> wrote:
> Hi Bin,
>
> On 14.03.2016 09:56, Bin Meng wrote:
>>
>> On Sun, Mar 13, 2016 at 10:52 AM, Simon Glass <sjg at chromium.org> wrote:
>>>
>>> Hi Stefan,
>>>
>>> On 11 March 2016 at 10:33, Stefan Roese <sr at denx.de> wrote:
>>>>
>>>> Hi Simon, Hi Bin,
>>>>
>>>> could you please let me know, what the status of I2C support for
>>>> BayTrail in U-Boot is? Is this driver generic enough to handle
>>>> BayTrail / Minnowboard MAX as well (I haven't looked in depth yet)?
>>>> Or what needs to be done to get BayTrail supported here?
>>>
>>>
>>> There is a dummy driver but it does not work. It needs to be filled
>>> out with an implementation using the datasheet or perhaps looking at
>>> coreboot smbus code.
>>>
>>
>> I guess Stefan is not looking for legacy SMBUS support, instead the
>> SIO I2C device on device 24 on BayTrail.
>
>
> I need to communicate with some of I2C devices connected to some
> of the I2C busses (e.g. bus #1) on this platform.
>
>> It is currently not
>> supported. The IP used on BayTrail is from Synopsis Designware, and
>> this I2C IP is also seen on Intel Quark.
>
>
> Is it documented somewhere, that these BayTrail I2C controllers
> are Synopsis Designware based / compatible? Could you please point
> me to this datasheet?

I don't think it is documented somewhere that the IP comes from
Synopsis Designware. I noticed this when I was working on Intel Quark
support, that lots of IPs on Intel Quark are from Synopsis (eg: we
have the Synopsis Designware ethernet driver working on Intel Quark).

>
>> It is possible we can reuse
>> U-Boot Synopsis I2C driver on Intel platform, with adaptations to PCI.
>
>
> I can definitely look into this. Thanks for letting me know.

Regards,
Bin