From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from saturn.retrosnub.co.uk ([178.18.118.26]:53525 "EHLO saturn.retrosnub.co.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756912AbcA3QIs (ORCPT ); Sat, 30 Jan 2016 11:08:48 -0500 Subject: Re: [PATCH] iio: pressure: mpl115: fix temperature offset sign To: Peter Meerwald-Stadler References: <1453306051-8817-1-git-send-email-akinobu.mita@gmail.com> <56A4FCCA.80500@kernel.org> Cc: Akinobu Mita , linux-iio@vger.kernel.org, Hartmut Knaack , Lars-Peter Clausen From: Jonathan Cameron Message-ID: <56ACE00E.3080103@kernel.org> Date: Sat, 30 Jan 2016 16:08:46 +0000 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=windows-1252 Sender: linux-iio-owner@vger.kernel.org List-Id: linux-iio@vger.kernel.org On 26/01/16 12:33, Peter Meerwald-Stadler wrote: > On Sun, 24 Jan 2016, Jonathan Cameron wrote: > >> On 20/01/16 16:07, Akinobu Mita wrote: >>> 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. > > Acked-by: Peter Meerwald-Stadler Applied to the fixes-togreg branch and marked for stable. Thanks, Jonathan > >>> Signed-off-by: Akinobu Mita >>> Cc: Jonathan Cameron >>> Cc: Hartmut Knaack >>> Cc: Lars-Peter Clausen >>> Cc: Peter Meerwald >>> Cc: linux-iio@vger.kernel.org >> Peter, >> >> I'd like your Ack on this given it is your driver. That way >> I can be lazy and not cross check the datasheet myself. >> >> Jonathan >>> --- >>> 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 138344c..73f2f0c 100644 >>> --- a/drivers/iio/pressure/mpl115.c >>> +++ b/drivers/iio/pressure/mpl115.c >>> @@ -118,7 +118,7 @@ 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: >>> >> >> -- >> To unsubscribe from this list: send the line "unsubscribe linux-iio" in >> the body of a message to majordomo@vger.kernel.org >> More majordomo info at http://vger.kernel.org/majordomo-info.html >> >