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Date:   Mon, 23 Apr 2018 07:26:51 +0100
From:   Lee Jones <lee.jones@linaro.org>
To:     Dan Carpenter <dan.carpenter@oracle.com>
Cc:     Jorge Eduardo Candelaria <jedu@slimlogic.co.uk>,
        linux-kernel@vger.kernel.org, kernel-janitors@vger.kernel.org
Subject: Re: [PATCH] mfd: tps65911-comparator: Fix an off by one bug
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On Fri, 20 Apr 2018, Dan Carpenter wrote:

> On Fri, Apr 20, 2018 at 09:39:09AM +0100, Lee Jones wrote:
> > On Fri, 20 Apr 2018, Dan Carpenter wrote:
> > 
> > > On Fri, Apr 20, 2018 at 09:09:43AM +0100, Lee Jones wrote:
> > > > On Thu, 19 Apr 2018, Dan Carpenter wrote:
> > > > 
> > > > > The tps_comparators[] array is used in two places.  We only access the
> > > > > COMP1 (1) and COMP2 (2) elements.  Unfortunately, we're accessing the
> > > > > wrong elements and also one element beyond the end of the array.  There
> > > > > was supposed to be a zero element at the start of the array which is
> > > > > isn't accessed but makes the math work out nicely.
> > > > 
> > > > I normally just apply patches from you, but this is a hack, right?
> > > 
> > > I liked it, I thought it was nice.  It uses 32 bytes but any fix was
> > > going to use *some* memory.  I don't have strong feelings about it
> > > though, if you want to write a different patch I can do that instead.
> > 
> > #define COMP                                    0
> > #define COMP1                                   1
> > #define COMP2                                   2
> > 
> > It's unclear what the defines mean, but if COMP really does exist (is
> > there a datasheet for this device?) then your solution is a suitable
> > one.  However, if there is a COMP, then why isn't it used?
> > 
> > If it doesn't actually exist then this would be more appropriate
> > change I think:
> > 
> > #define COMP1                                   0
> > #define COMP2                                   1
> > 
> 
> I hate to define something_one as zero...  Let me send a different
> patch for this and see what you think.

I guess that's the call of the hardware engineer/datasheet author?

-- 
Lee Jones [李琼斯]
Linaro Services Technical Lead
Linaro.org │ Open source software for ARM SoCs
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