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Subject: Re: [RESEND PATCH v4 3/8] gpio: 104-dio-48e: Utilize
 for_each_set_clump macro
To:     William Breathitt Gray <vilhelm.gray@gmail.com>
Cc:     linus.walleij@linaro.org, akpm@linux-foundation.org,
        linux-gpio@vger.kernel.org, linux-arch@vger.kernel.org,
        linux-kernel@vger.kernel.org, andriy.shevchenko@linux.intel.com
References: <cover.1538441919.git.vilhelm.gray@gmail.com>
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 <822be05b-092b-41c2-3c31-8981acd5cb9e@rasmusvillemoes.dk>
 <20181014041933.GA7335@icarus>
From:   Rasmus Villemoes <linux@rasmusvillemoes.dk>
Message-ID: <afbe5c62-f003-ca92-d185-8e6e9340c75d@rasmusvillemoes.dk>
Date:   Mon, 15 Oct 2018 13:59:33 +0200
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On 2018-10-14 06:19, William Breathitt Gray wrote:

> a bit value of 0 in the
> bits array does not necessarily mean the input was not requested, but
> may instead mean that the value at the input is 0;

sure enough, but...

> therefore, the caller
> must keep track of the requested inputs rather than try to deduce them
> from the values in the bits array.

...I don't agree that this logically follows. A caller might reasonably
expect not to find any bits set in positions other than those in mask. A
simple example would be caller that just tried to ask "are any of
_these_ inputs set"; it would be reasonable to implement that using
bitmap_empty() on the returned bitset, without first having to mask by
the mask he passed in.

Rasmus