[U-Boot] [PATCH v3 00/54] dm: Introduce new driver model uclasses

[York Sun]

On 06/30/2015 12:01 PM, Tom Rini wrote:
> On Tue, Jun 30, 2015 at 11:42:41AM -0700, York Sun wrote:
>>
>>
>> On 06/30/2015 11:33 AM, Simon Glass wrote:
>>> Hi York,
>>>
>>> On 30 June 2015 at 10:08, York Sun <yorksun at freescale.com> wrote:
>>>> Simon,
>>>>
>>>> Does the dm force using device tree? I was reviewing a patch set regarding SPI
>>>> and found OF_CONTROL has to be selected in order to get the driver model happy.
>>>>
>>>> My understanding of the driver model is both device tree and platform data are
>>>> allowed, like Linux. Is that still true?
>>>
>>> For buses you need device tree. I was rather hoping that we could
>>> avoid platform data on platforms that have device tree. What is the
>>> point?
>>>
>>
>> Simon,
>>
>> It happens on a platform not using device tree, but DM will be used.
>>
>> I prefer DM to have both, rather than being forced to use device tree, unless we
>> are going to enforce using device tree on all new platforms. Since device tree
>> is still an option, I feel it is best to support platform data, like Linux
>> drivers do.
> 
> Well, to what end?  My recollection is that in short, the kernel has
> both since platform data predates device tree (and converting platform
> data to device tree is still a thing that happens).  But we're trying to
> skip that intermediate step.  Are there platforms where you do not plan
> to use a device tree, ever?
> 

Tom,

I am not against using device tree at all. It is more dynamic and flexible. But
I don't see any indication that we favor device tree over pdata (except in the
code). If we are skipping pdata for new drivers, a clear message will be
helpful. That's what I am trying to get clarification.

York