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Date: Tue, 17 Dec 2013 13:04:35 +0000
From: Russell King - ARM Linux <linux@arm.linux.org.uk>
To: Tomasz Figa <tomasz.figa@gmail.com>
Cc: Thierry Reding <thierry.reding@gmail.com>,
        Xiubo Li <Li.Xiubo@freescale.com>, mark.rutland@arm.com,
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        Alison Wang <b18965@freescale.com>,
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Subject: Re: [PATCHv7 1/4] pwm: Add Freescale FTM PWM driver support
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On Tue, Dec 17, 2013 at 01:54:35PM +0100, Tomasz Figa wrote:
> On Tuesday 17 of December 2013 13:45:06 Thierry Reding wrote:
> > I fail to see how that would eliminate the problem with the types. That
> > said I don't actually see sparse complaining about any type mismatches.
> > That's probably because the various macros implicitly cast to u32.
> 
> Well, in BE variant you would read the register using __raw_readl() into
> a __be32 and then get an u32 from be32_to_cpu() and return it. Similarly
> for writes

__raw_readl() returns a u32, so you'll get a warning trying to assign a
u32 to a __be32.

We do have ioread32() and ioread32be() which do the appropriate conversion,
as well as the write versions too.  They both include the barrier if you're
overly concerned about that.