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Sender: Larry Finger <larry.finger@gmail.com>
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Date:   Thu, 31 Aug 2023 12:59:00 -0500
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Subject: Re: [PATCH] ssb-main: Fix division by zero in ssb_calc_clock_rate()
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From:   Larry Finger <Larry.Finger@lwfinger.net>
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On 8/31/23 11:05, Michael Büsch wrote:
> On Thu, 31 Aug 2023 10:07:33 +0300 (MSK)
> Ранд Дееб <deeb.rand@confident.ru> wrote:
> 
>> 1- Yes, I agree that your solution is simpler, and I thought about
>> it, but I thought that the one who set the value zero put it for some
>> reason, so I did not want to change it.
> 
> 
> Yes, I understand your reasoning and I had the same thought initially.
> But I looked into the code and I am pretty sure that there is no reason
> for the default case returning 0.
> In fact, I think returning a 1 as default makes much more sense as the
> default value for a factor.
> 
> Changing this from 0 to 1 will get my ack.

As far as I can tell, that return 0 is there only to silence the compiler as the 
switch statement has no default. As I said earlier, there have been no reports 
of divide by zero entries in this ancient driver, thus the value returned is not 
relevant. As a static tool sees the possibility of a returned zero leading to a 
potential divide by zero, making it a one it the only thing that makes sense.

I have no idea why this part of the patch has led to so much discussion!

Larry