Hello!

On 18/06/15 13:12, ext Sekhar Nori wrote:
>>>> Ah, beyond the evalboards, there are device-trees not linked into the 
>>>> kernel,
>>>>> >>>> but flashed into the boards, as originally in OF. They are part of 
>>>>> >>>> the HW, its
>>>>> >>>> description. Not part or description of the Kernel. And you have no 
>>>>> >>>> way to
>>>>> >>>> introduce this fix any more without updating this OF part if you go 
>>>>> >>>> with
>>>>> >>>> new compatible property.
>>> >> I see. So how critical is this fix? That should be described in the
>>> >> commit description. And if its really critical, stable kernel should be
>>> >> CCed too.
>> > 
>> > Now we got to the point, see below...
>> > 
>>>>>>>>>>> >>>>>>>>>> And from the other PoV, device-trees are for something 
>>>>>>>>>>> >>>>>>>>>> one cannot probe. We
>>>>>>>>>>> >>>>>>>>>> can probe for Keystone revisions and can free the 
>>>>>>>>>>> >>>>>>>>>> end-user from this headache
>>>>>>>>>>> >>>>>>>>>> completely.
>>>>>>> >>>>>> Keep in mind that this can invite driver patching whenever 
>>>>>>> >>>>>> version
>>>>>>> >>>>>> number is tinkered with in hardware - even for otherwise
>>>>>>> >>>>>> software-invsible changes.
>>>>> >>>>
>>>>> >>>> That's true. But I do not have an overview, how many IP versions do 
>>>>> >>>> you actually have?
>>>>> >>>> I've found one revision in Davinci manual, one revision in Keystone 
>>>>> >>>> manual, even
>>>>> >>>> including minor revision. Checking only major revision now can 
>>>>> >>>> survive couple of minor
>>>>> >>>> changes in IP.
>>> >> Yeah, sticking to major version should help. What I am worried about are
>>> >> versions coming in future, not those existing. And development on
>>> >> keystone architecture is ongoing in TI.
>> > 
>> > This is not really critical fix. Currently bus rate is lower than expected 
>> > because of these
>> > calculation errors. The fix maximizes the bus rate. So newer SoCs will run 
>> > little bit slower
>> > until support is added to this part of the code. Not really critical. So 
>> > no point in CCing
>> > stable maintainers also.
> If its not a critical fix, do we really need to care about older DTBs
> which have been ROM'ed into production?

I tend not to change the DT binding, but if majority will decide it's the way 
to go,
I'll prepare another patch. Let's wait for other opinions...

-- 
Best regards,
Alexander Sverdlin.
--
To unsubscribe from this list: send the line "unsubscribe linux-i2c" in
the body of a message to [email protected]
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Reply via email to