From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753621AbcCHAoT (ORCPT ); Mon, 7 Mar 2016 19:44:19 -0500 Received: from youngberry.canonical.com ([91.189.89.112]:38678 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753917AbcCGWwY (ORCPT ); Mon, 7 Mar 2016 17:52:24 -0500 From: Kamal Mostafa To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Akinobu Mita , Jonathan Cameron , Kamal Mostafa Subject: [PATCH 4.2.y-ckt 050/273] iio: pressure: mpl115: fix temperature offset sign Date: Mon, 7 Mar 2016 14:47:21 -0800 Message-Id: <1457391064-6660-51-git-send-email-kamal@canonical.com> X-Mailer: git-send-email 2.7.0 In-Reply-To: <1457391064-6660-1-git-send-email-kamal@canonical.com> References: <1457391064-6660-1-git-send-email-kamal@canonical.com> X-Extended-Stable: 4.2 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.2.8-ckt5 -stable review patch. If anyone has any objections, please let me know. ---8<------------------------------------------------------------ From: Akinobu Mita commit 431386e783a3a6c8b7707bee32d18c353b8688b2 upstream. According to the datasheet, the resolusion of temperature sensor is -5.35 counts/C. Temperature ADC is 472 counts at 25C. (https://www.sparkfun.com/datasheets/Sensors/Pressure/MPL115A1.pdf NOTE: This is older revision, but this information is removed from the latest datasheet from nxp somehow) Temp [C] = (Tadc - 472) / -5.35 + 25 = (Tadc - 605.750000) * -0.186915888 So the correct offset is -605.750000. Signed-off-by: Akinobu Mita Acked-by: Peter Meerwald-Stadler Signed-off-by: Jonathan Cameron Signed-off-by: Kamal Mostafa --- drivers/iio/pressure/mpl115.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/iio/pressure/mpl115.c b/drivers/iio/pressure/mpl115.c index f5ecd6e..a0d7dee 100644 --- a/drivers/iio/pressure/mpl115.c +++ b/drivers/iio/pressure/mpl115.c @@ -117,7 +117,7 @@ static int mpl115_read_raw(struct iio_dev *indio_dev, *val = ret >> 6; return IIO_VAL_INT; case IIO_CHAN_INFO_OFFSET: - *val = 605; + *val = -605; *val2 = 750000; return IIO_VAL_INT_PLUS_MICRO; case IIO_CHAN_INFO_SCALE: -- 2.7.0