From mboxrd@z Thu Jan  1 00:00:00 1970
From: Arnd Bergmann <arnd@arndb.de>
Subject: Re: [net-next-2.6 PATCH v2] can: SJA1000: generic OF platform bus driver
Date: Tue, 26 May 2009 10:10:30 +0100
Message-ID: <200905261010.31364.arnd@arndb.de>
References: <4A16BAAE.3070401@grandegger.com> <200905242327.15139.arnd@arndb.de> <4A1A418D.3040207@grandegger.com>
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Cc: Wolfgang Grandegger <wg@grandegger.com>,
	devicetree-discuss@ozlabs.org,
	Linux Netdev List <netdev@vger.kernel.org>
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On Monday 25 May 2009, Wolfgang Grandegger wrote:
> > Right, that makes sense. However, most drivers use the field to store the
> > physical address, not the iomap token. Maybe there should be a new field
> > in struct sja1000_priv for the virtual address, but that would be a change
> > to the base driver, not just to the OF portion.
> 
> Is that common practice? If yes, I will add a member to store the
> virtual address to struct sja1000_priv.

I grepped through the network driver for usage of ->base_addr, and
it's somewhat inconsistent. The majority of the users use it for
a physical address, but there are also a few that use it for the
__iomem token.

Casts between unsigned long and qualified (__iomem, __user, const, ...)
pointers do not cause a warning, but can easily lead to bugs when
another user casts to an unqualified pointer.

	Arnd <><