In temp_store(), for the hysteresis setting calculation there were two
errors. The first tries to clamp the hysteresis value by comparing the
required hysteresis value to THERM - 15C. This is incorrect since the
hysteresis value is a relative value whereas THERM - 15C is an absolute
value. This causes it to always select 15C for hysteresis. Change the
first parameter to THERM - val to compare two absolute temperatures.
The second error masks the wrong bits in the hysteresis register; indices
0 and 2 should zero bits [7:4] and preserve bits [3:0], and index 1 should
zero bits [3:0] and preserve bits [7:4].
Fixes: 1c301fc5394f ("hwmon: Add a driver for the ADT7475 hardware monitoring chip")
Signed-off-by: Tony O'Brien <tony.obrien@xxxxxxxxxxxxxxxxxxx>
---
drivers/hwmon/adt7475.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/drivers/hwmon/adt7475.c b/drivers/hwmon/adt7475.c
index 77222c35a38e..68233191798e 100644
--- a/drivers/hwmon/adt7475.c
+++ b/drivers/hwmon/adt7475.c
@@ -484,14 +484,14 @@ static ssize_t temp_store(struct device *dev, struct device_attribute *attr,
adt7475_read_hystersis(client);
temp = reg2temp(data, data->temp[THERM][sattr->index]);
- val = clamp_val(val, temp - 15000, temp);
+ val = clamp_val(temp - val, temp - 15000, temp);
val = (temp - val) / 1000;
if (sattr->index != 1) {
- data->temp[HYSTERSIS][sattr->index] &= 0xF0;
+ data->temp[HYSTERSIS][sattr->index] &= 0x0F;
data->temp[HYSTERSIS][sattr->index] |= (val & 0xF) << 4;
} else {
- data->temp[HYSTERSIS][sattr->index] &= 0x0F;
+ data->temp[HYSTERSIS][sattr->index] &= 0xF0;
data->temp[HYSTERSIS][sattr->index] |= (val & 0xF);
}
--
2.39.2
