From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mout.gmx.net ([212.227.15.18]:61995 "EHLO mout.gmx.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752399AbbHWTIQ (ORCPT ); Sun, 23 Aug 2015 15:08:16 -0400 Message-ID: <55DA1A17.2020304@gmx.de> Date: Sun, 23 Aug 2015 21:08:07 +0200 From: Hartmut Knaack MIME-Version: 1.0 To: Jonathan Cameron , Nicola Corna , Lars-Peter Clausen , Peter Meerwald CC: linux-iio@vger.kernel.org Subject: Re: [PATCH v3 1/2] iio: humidity: si7020: replaced bitmask on humidity values with range check References: <1440333248-3450-1-git-send-email-nicola@corna.info> <55D9EB58.50304@kernel.org> In-Reply-To: <55D9EB58.50304@kernel.org> Content-Type: text/plain; charset=windows-1252 Sender: linux-iio-owner@vger.kernel.org List-Id: linux-iio@vger.kernel.org Jonathan Cameron schrieb am 23.08.2015 um 17:48: > On 23/08/15 13:34, Nicola Corna wrote: >> The maximum possible value for the relative humidity is 55575 (100%RH). >> This value, if shifted right by 2 bits, uses 14 bits and masking it with >> a 12 bit mask removes 2 meaningful bits. >> The masking has been replaced with a range check that sets the minimum >> value at 786 (0%RH) and the maximum at 13893 (99.998%RH). >> >> Signed-off-by: Nicola Corna >> Reviewed-by: Hartmut Knaack > Applied. I have taken the view that previously the driver > was 'limited' by this rather than a nasty bug. > Hence I've queued it up for the next merge window. > Applied to the togreg branch of iio.git > This doesn't work, clamp_val() returns a result, which has to be assigned to a variable (*val) in this case. I thought I pointed that out in V2. > Thanks, > > Jonathan >> --- >> drivers/iio/humidity/si7020.c | 6 +++++- >> 1 file changed, 5 insertions(+), 1 deletion(-) >> >> diff --git a/drivers/iio/humidity/si7020.c b/drivers/iio/humidity/si7020.c >> index fa3b809..06e6659 100644 >> --- a/drivers/iio/humidity/si7020.c >> +++ b/drivers/iio/humidity/si7020.c >> @@ -57,8 +57,12 @@ static int si7020_read_raw(struct iio_dev *indio_dev, >> if (ret < 0) >> return ret; >> *val = ret >> 2; >> + /* >> + * Humidity values can slightly exceed the 0-100%RH >> + * range and should be corrected by software >> + */ >> if (chan->type == IIO_HUMIDITYRELATIVE) >> - *val &= GENMASK(11, 0); >> + clamp_val(*val, 786, 13893); This needs to be: *val = clamp_val(...) >> return IIO_VAL_INT; >> case IIO_CHAN_INFO_SCALE: >> if (chan->type == IIO_TEMP) >> > > -- > 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 >