[PATCH 6.1 315/473] iio: pressure: dps310: support negative temperature values

Greg Kroah-Hartman
2024-06-06T14:17:09Z

From: Thomas Haemmerle <thomas.haemmerle@leica-geosystems.com>

[ Upstream commit 9dd6b32e76ff714308964cd9ec91466a343dcb8b ]

The current implementation interprets negative values returned from
`dps310_calculate_temp` as error codes.
This has a side effect that when negative temperature values are
calculated, they are interpreted as error.

Fix this by using the return value only for error handling and passing a
pointer for the value.

Fixes: ba6ec48e76bc ("iio: Add driver for Infineon DPS310")
Signed-off-by: Thomas Haemmerle <thomas.haemmerle@leica-geosystems.com>
Link: https://lore.kernel.org/r/20240415105030.1161770-2-thomas.haemmerle@leica-geosystems.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/iio/pressure/dps310.c | 11 ++++++-----
1 file changed, 6 insertions(+), 5 deletions(-)

diff --git a/drivers/iio/pressure/dps310.c b/drivers/iio/pressure/dps310.c
index db1b1e48225aa..519fcd425b6a3 100644
--- a/drivers/iio/pressure/dps310.c
+++ b/drivers/iio/pressure/dps310.c
@@ -730,7 +730,7 @@ static int dps310_read_pressure(struct dps310_data *data, int *val, int *val2,
}
}

-static int dps310_calculate_temp(struct dps310_data *data)
+static int dps310_calculate_temp(struct dps310_data *data, int *val)
{
s64 c0;
s64 t;
@@ -746,7 +746,9 @@ static int dps310_calculate_temp(struct dps310_data *data)
t = c0 + ((s64)data->temp_raw * (s64)data->c1);

/* Convert to milliCelsius and scale the temperature */
- return (int)div_s64(t * 1000LL, kt);
+ *val = (int)div_s64(t * 1000LL, kt);
+
+ return 0;
}

static int dps310_read_temp(struct dps310_data *data, int *val, int *val2,
@@ -768,11 +770,10 @@ static int dps310_read_temp(struct dps310_data *data, int *val, int *val2,
if (rc)
return rc;

- rc = dps310_calculate_temp(data);
- if (rc < 0)
+ rc = dps310_calculate_temp(data, val);
+ if (rc)
return rc;

- *val = rc;
return IIO_VAL_INT;

case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
--
2.43.0