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Date: Mon, 26 Jan 2015 21:05:19 +0000
From: Jonathan Cameron <jic23@kernel.org>
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To: Lars-Peter Clausen <lars@metafoo.de>,
	Rasmus Villemoes <linux@rasmusvillemoes.dk>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>
CC: Hartmut Knaack <knaack.h@gmx.de>,
	Peter Meerwald <pmeerw@pmeerw.net>, linux-iio@vger.kernel.org,
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Subject: Re: [PATCH] staging: iio: ad2s1200: Fix sign extension
References: <1421968196-17193-1-git-send-email-linux@rasmusvillemoes.dk> <54C20CAF.3010901@metafoo.de>
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On 23/01/15 08:56, Lars-Peter Clausen wrote:
> On 01/23/2015 12:09 AM, Rasmus Villemoes wrote:
>> The line above makes vel a 12-bit quantity (st->rx[] is u8). The
>> intention is to sign-extend vel using bit 11 as the sign bit. But
>> because of C's promotion rules "vel = (vel << 4) >> 4;" is actually a
>> no-op, since vel is promoted to int before the inner
>> shift. sign_extend32 works equally well for 8 and 16 bits types, so
>> use that.
>>
>> Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
> 
> Acked-by: Lars-Peter Clausen <lars@metafoo.de>
Applied to fixes-togreg branch of iio.git.

Thanks,

Jonathan