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Subject: Re: [PATCH 1/5] pdev: Fix platform device resource linking
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From: Pantelis Antoniou <panto@antoniou-consulting.com>
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Date: Tue, 6 Aug 2013 12:45:42 +0300
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To: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Hi Greg,

On Aug 6, 2013, at 12:36 PM, Greg Kroah-Hartman wrote:

> On Tue, Aug 06, 2013 at 10:53:40AM +0300, Pantelis Antoniou wrote:
>> Platform device removal uncovered a number of problems with
>> the way resources are handled in the core platform code.
>> 
>> Resources now form child/parent linkages and this requires
>> proper linking of the resources. On top of that the OF core
>> directly creates it's own platform devices. Simplify things
>> by providing helper functions that manage the linking properly.
> 
> Ugh, the OF core shouldn't be creating platform devices.  Well, yes, I
> know it does that today, but ick, ick, ick.
> 

Yep, ick, ick, ick is the correct form.

>> Two functions are provided:
>> 
>> platform_device_link_resources(), which links all the
>> linkable resources (if not already linked).
>> 
>> and platform_device_unlink_resources(), which unlinks all the
>> resources.
> 
> Why would anyone need to call this?  I'm getting the feeling that OF
> should just have it's own bus of devices to handle this type of mess.
> ACPI is going through the same rewrite for this same type of problem
> (they did things differently.)  I suggest you work with the ACPI
> developers to so the same thing they are, to solve it correctly for
> everyone.
> 

It's the same problem really. Another bus type might not fly well.
The same device driver should be (in theory) be made to work unchanged
either on an OF/ACPI/Fex( :) ) setup.

What would it take to move all this into driver core?

> thanks,
> 
> greg k-h

Regards

-- Pantelis