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Date: Thu, 17 Oct 2013 15:51:54 +0200
From: Lars-Peter Clausen <lars@metafoo.de>
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To: Timur Tabi <timur@tabi.org>
Subject: Re: [alsa-devel] [PATCHv1 1/8] ALSA: Add SAI SoC Digital Audio
 Interface driver.
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On 10/17/2013 03:37 PM, Timur Tabi wrote:
> Lars-Peter Clausen wrote:
>>> >Maybe I've been out of the loop for too long, but why is that a particular
>>> >problem with this driver?
> 
>> It is usually something you'd want to check in general to make sure that you
>> don't have multiple device that access the same iomem region at the same
>> time.
> 
> I understand that, but I'm trying to figure out why of_iomap() is okay for
> hundreds of other drivers, but not this one.  I've used it dozens of times
> myself, without ever worrying about overlapping regions.

The driver would work fine with just of_iomap(). But the resource range
check comes basically for free and it does help to catch errors, so I'd
recommend on using it rather than not using it.

- Lars