[U-Boot] [PATCH v2 6/7] tegra: Select I2C ordering for Seaboard

[Stephen Warren]

On 02/03/2012 05:36 PM, Simon Glass wrote:
> Hi Stephen,
> 
> On Fri, Feb 3, 2012 at 4:25 PM, Stephen Warren <swarren at nvidia.com> wrote:
>> On 02/03/2012 05:19 PM, Simon Glass wrote:
>>> Hi Stephen,
>>>
>>> On Fri, Feb 3, 2012 at 4:14 PM, Stephen Warren <swarren at nvidia.com> wrote:
>>>> On 02/03/2012 04:24 PM, Simon Glass wrote:
>>>>> Hi Stephen,
>>>>>
>>>>> On Thu, Jan 19, 2012 at 12:56 PM, Stephen Warren <swarren at nvidia.com> wrote:
>>>>>> On 01/12/2012 12:00 PM, Simon Glass wrote:
>>>>>>> Select the port ordering for I2C on Seaboard.
>>>>>>>
>>>>>>> Signed-off-by: Simon Glass <sjg at chromium.org>
>>>>>>> Acked-by: Stephen Warren <swarren at nvidia.com>
>>>>>>
>>>>>> This isn't the patch that I ack'd.
>>>>>
>>>>> Sorry, I added the disable.
>>>>>
>>>>>>
>>>>>>> diff --git a/board/nvidia/dts/tegra2-seaboard.dts b/board/nvidia/dts/tegra2-seaboard.dts
>>>>>>
>>>>>> Unrelated to this patch, but shouldn't that be tegra-seaboard.dts not
>>>>>> tegra2-seaboard.dts to match the naming in the kernel?
>>>>>>
>>>>>>> @@ -44,4 +49,9 @@
>>>>>>>       usb at c5004000 {
>>>>>>>               status = "disabled";
>>>>>>>       };
>>>>>>> +
>>>>>>> +     i2c at 7000c400 {
>>>>>>> +             status = "disabled";
>>>>>>> +     };
>>>>>>> +
>>>>>>>  };
>>>>>>
>>>>>> That chunk wasn't in the original patch, and doesn't match the kernel's
>>>>>> .dts file (and I believe that I2C controller really is in use, so
>>>>>> shouldn't be disabled).
>>>>>
>>>>> It cannot be used - remember the discussion about pinmux? We elected
>>>>> to disable I2C1 at present since you didn't like my nvidia,pinmux
>>>>> binding for selecting which value to pass to funcmux. The fix is to
>>>>> pass 1 instead of 0 for that port, but we have no clean way to specify
>>>>> this.
>>>>>
>>>>> Rather disable it than leave it enabled and not working.
>>>>
>>>> Rather than having the .dts file not correctly describe the HW, wouldn't
>>>> it be better to limit U-Boot's to only initializing the 1 I2C controller
>>>> that it knows the valid pinmux setting for?
>>>
>>> Well, on Seaboard I2C2 (sorry, not I2C1 as I said in my email) is not
>>> used or connected to anything, so it is a reasonable description of
>>> the hardware. The other 3 pinmux settings are valid.
>>
>> As best I can tell from my schematics, all 4 I2C ports are used on both
>> Seaboard and Springbank.
> 
> I don't know about Springbank, but this patch is for Seaboard.
> 
> There is nothing on the bus and I can't see anything on the schematic.
> Can you please tell me what it is used for and which pins you are
> referring to?

GEN2_I2C_SCL/SDA are connected to:

J4 (battery or charger)
TPM
J6 (touchscreen connector)
J26 (mini PCIe)
J18 (satellite board)

I assume you have access to the schematics?

-- 
nvpublic