From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754163AbbAVXeO (ORCPT ); Thu, 22 Jan 2015 18:34:14 -0500 Received: from mail-lb0-f170.google.com ([209.85.217.170]:39059 "EHLO mail-lb0-f170.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752581AbbAVXeM (ORCPT ); Thu, 22 Jan 2015 18:34:12 -0500 From: Rasmus Villemoes To: Lars-Peter Clausen , Michael Hennerich , Jonathan Cameron , Hartmut Knaack , Peter Meerwald Cc: Rasmus Villemoes , linux-iio@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH] iio: imu: adis16400: Fix sign extension Date: Fri, 23 Jan 2015 00:34:02 +0100 Message-Id: <1421969642-18167-1-git-send-email-linux@rasmusvillemoes.dk> X-Mailer: git-send-email 2.1.3 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The intention is obviously to sign-extend a 12 bit quantity. But because of C's promotion rules, the assignment is equivalent to "val16 &= 0xfff;". Use the proper API for this. Signed-off-by: Rasmus Villemoes --- drivers/iio/imu/adis16400_core.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/iio/imu/adis16400_core.c b/drivers/iio/imu/adis16400_core.c index b70873de04ea..fa795dcd5f75 100644 --- a/drivers/iio/imu/adis16400_core.c +++ b/drivers/iio/imu/adis16400_core.c @@ -26,6 +26,7 @@ #include #include #include +#include #include #include @@ -414,7 +415,7 @@ static int adis16400_read_raw(struct iio_dev *indio_dev, mutex_unlock(&indio_dev->mlock); if (ret) return ret; - val16 = ((val16 & 0xFFF) << 4) >> 4; + val16 = sign_extend32(val16, 11); *val = val16; return IIO_VAL_INT; case IIO_CHAN_INFO_OFFSET: -- 2.1.3