From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:53757 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754699AbbEMTCC (ORCPT ); Wed, 13 May 2015 15:02:02 -0400 Subject: patch "iio: adc: spmi-vadc: Fix overflow in output value normalization" added to staging-linus To: ivan.ivanov@linaro.org, jic23@kernel.org, stable@vger.kernel.org From: Date: Wed, 13 May 2015 12:02:00 -0700 Message-ID: <14315437204884@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: This is a note to let you know that I've just added the patch titled iio: adc: spmi-vadc: Fix overflow in output value normalization to my staging git tree which can be found at git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging.git in the staging-linus branch. The patch will show up in the next release of the linux-next tree (usually sometime within the next 24 hours during the week.) The patch will hopefully also be merged in Linus's tree for the next -rc kernel release. If you have any questions about this process, please let me know. >>From 937125aca00e0478c4024afe58bc620a7bbe2a93 Mon Sep 17 00:00:00 2001 From: "Ivan T. Ivanov" Date: Fri, 17 Apr 2015 17:51:08 +0300 Subject: iio: adc: spmi-vadc: Fix overflow in output value normalization With 'dx' equal to 0.625V and 15 bit ADC, calculations overflow when difference against GND is ~20% of the ADC range. Fix this. Signed-off-by: Ivan T. Ivanov Cc: Signed-off-by: Jonathan Cameron --- drivers/iio/adc/qcom-spmi-vadc.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/drivers/iio/adc/qcom-spmi-vadc.c b/drivers/iio/adc/qcom-spmi-vadc.c index 3211729bcb0b..0c4618b4d515 100644 --- a/drivers/iio/adc/qcom-spmi-vadc.c +++ b/drivers/iio/adc/qcom-spmi-vadc.c @@ -18,6 +18,7 @@ #include #include #include +#include #include #include #include @@ -471,11 +472,11 @@ static s32 vadc_calibrate(struct vadc_priv *vadc, const struct vadc_channel_prop *prop, u16 adc_code) { const struct vadc_prescale_ratio *prescale; - s32 voltage; + s64 voltage; voltage = adc_code - vadc->graph[prop->calibration].gnd; voltage *= vadc->graph[prop->calibration].dx; - voltage = voltage / vadc->graph[prop->calibration].dy; + voltage = div64_s64(voltage, vadc->graph[prop->calibration].dy); if (prop->calibration == VADC_CALIB_ABSOLUTE) voltage += vadc->graph[prop->calibration].dx; @@ -487,7 +488,7 @@ static s32 vadc_calibrate(struct vadc_priv *vadc, voltage = voltage * prescale->den; - return voltage / prescale->num; + return div64_s64(voltage, prescale->num); } static int vadc_decimation_from_dt(u32 value) -- 2.4.0