Re: [PATCH] comedi: dmm32at: Fix coding style - use BIT macro

From	Dan Carpenter <dan.carpenter@oracle.com>
Newsgroups	linux.kernel
Subject	Re: [PATCH] comedi: dmm32at: Fix coding style - use BIT macro
Date	2015-11-19 09:00 +0100
Message-ID	<qwsim-6pI-3@gated-at.bofh.it> (permalink)
References	<quMuS-6NX-9@gated-at.bofh.it> <qwdMm-5n6-7@gated-at.bofh.it>
Organization	linux.* mail to news gateway

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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

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Re: [PATCH] comedi: dmm32at: Fix coding style - use BIT macro Ian Abbott <abbotti@mev.co.uk> - 2015-11-18 17:30 +0100
  Re: [PATCH] comedi: dmm32at: Fix coding style - use BIT macro Ian Abbott <abbotti@mev.co.uk> - 2015-11-18 17:40 +0100
  Re: [PATCH] comedi: dmm32at: Fix coding style - use BIT macro Dan Carpenter <dan.carpenter@oracle.com> - 2015-11-19 09:00 +0100

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