From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH v2 1/1] drivers: net: davinci_cpdma: acknowledge
 interrupt properly
Date: Fri, 15 Feb 2013 15:20:25 -0500 (EST)
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From: Joe Perches <joe@perches.com>
Date: Fri, 15 Feb 2013 12:18:59 -0800

> On Fri, 2013-02-15 at 15:05 -0500, David Miller wrote:
>> From: Mugunthan V N <mugunthanvnm@ti.com>
>> Date: Thu, 14 Feb 2013 23:56:46 +0530
>> 
>> > +enum {
>> > +     CPDMA_EOI_RX_THRESH = 0,
>> > +     CPDMA_EOI_RX,
>> > +     CPDMA_EOI_TX,
>> > +     CPDMA_EOI_MISC,
>> > +};
>> 
>> Do not use enumerations for hardware register values, which must be
>> exact, otherwise you are potentially going to succumb to the vagaries
>> of C language enumeration value assignment.
> 
> Vagaries?
> 
> In what way is c enumeration (6.7.2.2) vague?
> char vs int?  Isn't smaller mostly better?
> 
> Concern about possible future reordering given an
> insertion or deletion might be the only consideration
> I could imagine.

Right.  That's why you should use explicit CPP defines for
register offsets and values.