| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-Id: <20250821-hdc3020-units-fix-v1-2-6ab0bc353c5e@liebherr.com>
Date: Thu, 21 Aug 2025 17:23:55 +0200
From: Dimitri Fedrau via B4 Relay <devnull+dimitri.fedrau.liebherr.com@...nel.org>
To: Javier Carrasco <javier.carrasco.cruz@...il.com>,
Li peiyu <579lpy@...il.com>, Jonathan Cameron <jic23@...nel.org>,
David Lechner <dlechner@...libre.com>,
Nuno Sá <nuno.sa@...log.com>,
Andy Shevchenko <andy@...nel.org>, Dimitri Fedrau <dima.fedrau@...il.com>
Cc: Jonathan Cameron <Jonathan.Cameron@...wei.com>,
linux-iio@...r.kernel.org, linux-kernel@...r.kernel.org,
Dimitri Fedrau <dimitri.fedrau@...bherr.com>,
Chris Lesiak <chris.lesiak@...orbio.com>
Subject: [PATCH 2/2] iio: humditiy: hdc3020: fix units for thresholds and
hysteresis
From: Dimitri Fedrau <dimitri.fedrau@...bherr.com>
According to the ABI the units after application of scale and offset are
milli degree celsius for temperature thresholds and milli percent for
relative humidity thresholds. Change scale factor to fix this issue.
Fixes: 3ad0e7e5f0cb ("iio: humidity: hdc3020: add threshold events support")
Reported-by: Chris Lesiak <chris.lesiak@...orbio.com>
Signed-off-by: Dimitri Fedrau <dimitri.fedrau@...bherr.com>
---
drivers/iio/humidity/hdc3020.c | 42 +++++++++++++++++++++---------------------
1 file changed, 21 insertions(+), 21 deletions(-)
diff --git a/drivers/iio/humidity/hdc3020.c b/drivers/iio/humidity/hdc3020.c
index 9de52de628e04263a2b62a512a36203d6c02c5e0..8134d32fceedd2b88d9d4ed7bc9062759045aafe 100644
--- a/drivers/iio/humidity/hdc3020.c
+++ b/drivers/iio/humidity/hdc3020.c
@@ -379,12 +379,12 @@ static int hdc3020_thresh_get_temp(u16 thresh)
* Get the temperature threshold from 9 LSBs, shift them to get
* the truncated temperature threshold representation and
* calculate the threshold according to the formula in the
- * datasheet. Result is degree celsius scaled by 65535.
+ * datasheet. Result is degree celsius scaled by 13107.
*/
temp = FIELD_GET(HDC3020_THRESH_TEMP_MASK, thresh) <<
HDC3020_THRESH_TEMP_TRUNC_SHIFT;
- return -2949075 + (175 * temp);
+ return -589815 + (35 * temp);
}
static int hdc3020_thresh_get_hum(u16 thresh)
@@ -395,12 +395,12 @@ static int hdc3020_thresh_get_hum(u16 thresh)
* Get the humidity threshold from 7 MSBs, shift them to get the
* truncated humidity threshold representation and calculate the
* threshold according to the formula in the datasheet. Result is
- * percent scaled by 65535.
+ * percent scaled by 13107.
*/
hum = FIELD_GET(HDC3020_THRESH_HUM_MASK, thresh) <<
HDC3020_THRESH_HUM_TRUNC_SHIFT;
- return hum * 100;
+ return hum * 20;
}
static u16 hdc3020_thresh_set_temp(int s_temp, u16 curr_thresh)
@@ -455,8 +455,8 @@ int hdc3020_thresh_clr(s64 s_thresh, s64 s_hyst, enum iio_event_direction dir)
else
s_clr = s_thresh + s_hyst;
- /* Divide by 65535 to get units of micro */
- return div_s64(s_clr, 65535);
+ /* Divide by 13107 to get units of micro */
+ return div_s64(s_clr, 13107);
}
static int _hdc3020_write_thresh(struct hdc3020_data *data, u16 reg, u16 val)
@@ -507,7 +507,7 @@ static int hdc3020_write_thresh(struct iio_dev *indio_dev,
clr = ret;
/* Scale value to include decimal part into calculations */
- s_val = (val < 0) ? (val * 1000000 - val2) : (val * 1000000 + val2);
+ s_val = (val < 0) ? (val * 1000 - val2) : (val * 1000 + val2);
switch (chan->type) {
case IIO_TEMP:
switch (info) {
@@ -523,7 +523,7 @@ static int hdc3020_write_thresh(struct iio_dev *indio_dev,
/* Calculate old hysteresis */
s_thresh = (s64)hdc3020_thresh_get_temp(thresh) * 1000000;
s_clr = (s64)hdc3020_thresh_get_temp(clr) * 1000000;
- s_hyst = div_s64(abs(s_thresh - s_clr), 65535);
+ s_hyst = div_s64(abs(s_thresh - s_clr), 13107);
/* Set new threshold */
thresh = reg_val;
/* Set old hysteresis */
@@ -532,16 +532,16 @@ static int hdc3020_write_thresh(struct iio_dev *indio_dev,
case IIO_EV_INFO_HYSTERESIS:
/*
* Function hdc3020_thresh_get_temp returns temperature
- * in degree celsius scaled by 65535. Scale by 1000000
+ * in degree celsius scaled by 13107. Scale by 1000000
* to be able to subtract scaled hysteresis value.
*/
s_thresh = (s64)hdc3020_thresh_get_temp(thresh) * 1000000;
/*
* Units of s_val are in micro degree celsius, scale by
- * 65535 to get same units as s_thresh.
+ * 13107 to get same units as s_thresh.
*/
s_val = min(abs(s_val), HDC3020_MAX_TEMP_HYST_MICRO);
- s_hyst = (s64)s_val * 65535;
+ s_hyst = (s64)s_val * 13107;
s_clr = hdc3020_thresh_clr(s_thresh, s_hyst, dir);
s_clr = max(s_clr, HDC3020_MIN_TEMP_MICRO);
s_clr = min(s_clr, HDC3020_MAX_TEMP_MICRO);
@@ -565,7 +565,7 @@ static int hdc3020_write_thresh(struct iio_dev *indio_dev,
/* Calculate old hysteresis */
s_thresh = (s64)hdc3020_thresh_get_hum(thresh) * 1000000;
s_clr = (s64)hdc3020_thresh_get_hum(clr) * 1000000;
- s_hyst = div_s64(abs(s_thresh - s_clr), 65535);
+ s_hyst = div_s64(abs(s_thresh - s_clr), 13107);
/* Set new threshold */
thresh = reg_val;
/* Try to set old hysteresis */
@@ -574,15 +574,15 @@ static int hdc3020_write_thresh(struct iio_dev *indio_dev,
case IIO_EV_INFO_HYSTERESIS:
/*
* Function hdc3020_thresh_get_hum returns relative
- * humidity in percent scaled by 65535. Scale by 1000000
+ * humidity in percent scaled by 13107. Scale by 1000000
* to be able to subtract scaled hysteresis value.
*/
s_thresh = (s64)hdc3020_thresh_get_hum(thresh) * 1000000;
/*
- * Units of s_val are in micro percent, scale by 65535
+ * Units of s_val are in micro percent, scale by 13107
* to get same units as s_thresh.
*/
- s_hyst = (s64)s_val * 65535;
+ s_hyst = (s64)s_val * 13107;
s_clr = hdc3020_thresh_clr(s_thresh, s_hyst, dir);
s_clr = max(s_clr, 0);
s_clr = min(s_clr, HDC3020_MAX_HUM_MICRO);
@@ -630,7 +630,7 @@ static int hdc3020_read_thresh(struct iio_dev *indio_dev,
thresh = hdc3020_thresh_get_temp(ret);
switch (info) {
case IIO_EV_INFO_VALUE:
- *val = thresh;
+ *val = thresh * 1000;
break;
case IIO_EV_INFO_HYSTERESIS:
ret = hdc3020_read_be16(data, reg_clr);
@@ -638,18 +638,18 @@ static int hdc3020_read_thresh(struct iio_dev *indio_dev,
return ret;
clr = hdc3020_thresh_get_temp(ret);
- *val = abs(thresh - clr);
+ *val = abs(thresh - clr) * 1000;
break;
default:
return -EOPNOTSUPP;
}
- *val2 = 65535;
+ *val2 = 13107;
return IIO_VAL_FRACTIONAL;
case IIO_HUMIDITYRELATIVE:
thresh = hdc3020_thresh_get_hum(ret);
switch (info) {
case IIO_EV_INFO_VALUE:
- *val = thresh;
+ *val = thresh * 1000;
break;
case IIO_EV_INFO_HYSTERESIS:
ret = hdc3020_read_be16(data, reg_clr);
@@ -657,12 +657,12 @@ static int hdc3020_read_thresh(struct iio_dev *indio_dev,
return ret;
clr = hdc3020_thresh_get_hum(ret);
- *val = abs(thresh - clr);
+ *val = abs(thresh - clr) * 1000;
break;
default:
return -EOPNOTSUPP;
}
- *val2 = 65535;
+ *val2 = 13107;
return IIO_VAL_FRACTIONAL;
default:
return -EOPNOTSUPP;
--
2.39.5
Powered by blists - more mailing lists