Path: csiph.com!news.mixmin.net!aioe.org!bofh.it!news.nic.it!robomod From: Greg Kroah-Hartman Newsgroups: linux.kernel Subject: [PATCH 4.4 036/118] iio: accel: kxsd9: Fix scaling bug Date: Thu, 22 Sep 2016 19:40:02 +0200 Message-ID: References: X-Mailer: git-send-email 2.10.0 User-Agent: quilt/0.64 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: robomod@news.nic.it List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Approved: robomod@news.nic.it Lines: 39 Organization: linux.* mail to news gateway X-Original-Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Jonathan Cameron , Linus Walleij X-Original-Date: Thu, 22 Sep 2016 19:28:56 +0200 X-Original-Message-ID: <20160922172940.494817917@linuxfoundation.org> X-Original-References: <20160922172938.643879685@linuxfoundation.org> X-Original-Sender: linux-kernel-owner@vger.kernel.org Xref: csiph.com linux.kernel:1489133 4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Linus Walleij commit 307fe9dd11ae44d4f8881ee449a7cbac36e1f5de upstream. All the scaling of the KXSD9 involves multiplication with a fraction number < 1. However the scaling value returned from IIO_INFO_SCALE was unpredictable as only the micros of the value was assigned, and not the integer part, resulting in scaling like this: $cat in_accel_scale -1057462640.011978 Fix this by assigning zero to the integer part. Tested-by: Jonathan Cameron Signed-off-by: Linus Walleij Signed-off-by: Jonathan Cameron Signed-off-by: Greg Kroah-Hartman --- drivers/iio/accel/kxsd9.c | 1 + 1 file changed, 1 insertion(+) --- a/drivers/iio/accel/kxsd9.c +++ b/drivers/iio/accel/kxsd9.c @@ -166,6 +166,7 @@ static int kxsd9_read_raw(struct iio_dev ret = spi_w8r8(st->us, KXSD9_READ(KXSD9_REG_CTRL_C)); if (ret < 0) goto error_ret; + *val = 0; *val2 = kxsd9_micro_scales[ret & KXSD9_FS_MASK]; ret = IIO_VAL_INT_PLUS_MICRO; break;