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Date:   Fri, 6 May 2022 14:40:09 +0100 (BST)
From:   "Maciej W. Rozycki" <macro@orcam.me.uk>
To:     Geert Uytterhoeven <geert@linux-m68k.org>
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Subject: Re: [RFC v2 01/39] Kconfig: introduce HAS_IOPORT option and select
 it as necessary
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On Fri, 6 May 2022, Geert Uytterhoeven wrote:

> A loooong time ago,  it was suggested to add register accessor
> functions to struct device, so e.g. readl(dev, offset) would call
> into these accessors, which would implement the bus-specific behavior.
> No more worries about readl(), __raw_readl(), ioread32b(), or whatever
> quirk is needed, at the (small on nowadays' machines) expense of
> some indirection...

 I guess you'd need an additional parameter for the endianness policy 
required (to match either bit or byte lanes, according to ultimate data 
interpretation) where crossing between buses of a different endianness 
each.  Otherwise you'd end up with the mess elsewhere.

  Maciej