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Date: Thu, 19 Nov 2015 10:51:32 +0300
From: Dan Carpenter <dan.carpenter@oracle.com>
To: Ian Abbott <abbotti@mev.co.uk>
Cc: Ranjith Thangavel <ranjithece24@gmail.com>, gregkh@linuxfoundation.org,
        devel@driverdev.osuosl.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] comedi: dmm32at: Fix coding style - use BIT macro
Message-ID: <20151119075132.GT18797@mwanda>
References: <1447521036-23550-1-git-send-email-ranjithece24@gmail.com>
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On Wed, Nov 18, 2015 at 04:26:52PM +0000, Ian Abbott wrote:
> >+#define DMM32AT_AI_CFG_SCINT_10US	(BIT(5) & ~BIT(4))
> >+#define DMM32AT_AI_CFG_SCINT_5US	(BIT(5) | BIT(4))
> 
> The values of DMM32AT_AI_CFG_SCINT_20US etc. are numerically
> correct, but look a bit strange.  The `(BIT(5) & ~BIT(4))` looks
> especially strange and could be changed to `BIT(5)`.  These are all
> really shifted 2-bit values, so perhaps the BIT() macro isn't the
> best representation.
> 

BIT(5) & ~BIT(4) is silly.  Don't do that.

The original code was fine.

regards,
dan carpenter