From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755441AbdDJRTC (ORCPT ); Mon, 10 Apr 2017 13:19:02 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:35772 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755298AbdDJQuP (ORCPT ); Mon, 10 Apr 2017 12:50:15 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Nikolaus Schulz , Lars-Peter Clausen , Jonathan Cameron Subject: [PATCH 4.10 014/110] iio: core: Fix IIO_VAL_FRACTIONAL_LOG2 for negative values Date: Mon, 10 Apr 2017 18:42:05 +0200 Message-Id: <20170410164202.049873180@linuxfoundation.org> X-Mailer: git-send-email 2.12.2 In-Reply-To: <20170410164201.247583164@linuxfoundation.org> References: <20170410164201.247583164@linuxfoundation.org> User-Agent: quilt/0.65 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.10-stable review patch. If anyone has any objections, please let me know. ------------------ From: Nikolaus Schulz commit 7fd6592d1287046f61bfd3cda3c03cd35be490f7 upstream. Fix formatting of negative values of type IIO_VAL_FRACTIONAL_LOG2 by switching from do_div(), which can't handle negative numbers, to div_s64_rem(). Also use shift_right for shifting, which is safe with negative values. Signed-off-by: Nikolaus Schulz Reviewed-by: Lars-Peter Clausen Signed-off-by: Jonathan Cameron Signed-off-by: Greg Kroah-Hartman --- drivers/iio/industrialio-core.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) --- a/drivers/iio/industrialio-core.c +++ b/drivers/iio/industrialio-core.c @@ -608,10 +608,9 @@ static ssize_t __iio_format_value(char * tmp0 = (int)div_s64_rem(tmp, 1000000000, &tmp1); return snprintf(buf, len, "%d.%09u", tmp0, abs(tmp1)); case IIO_VAL_FRACTIONAL_LOG2: - tmp = (s64)vals[0] * 1000000000LL >> vals[1]; - tmp1 = do_div(tmp, 1000000000LL); - tmp0 = tmp; - return snprintf(buf, len, "%d.%09u", tmp0, tmp1); + tmp = shift_right((s64)vals[0] * 1000000000LL, vals[1]); + tmp0 = (int)div_s64_rem(tmp, 1000000000LL, &tmp1); + return snprintf(buf, len, "%d.%09u", tmp0, abs(tmp1)); case IIO_VAL_INT_MULTIPLE: { int i;