Unlike the temperature thresholds the temperature data is a 9-bit signed
value. This allows and additional 0.5 degrees of precision on the
reading but makes handling negative values slightly harder. In order to
have sign-extension applied correctly the 9-bit value is stored in the
upper bits of a signed 16-bit value. When presenting this in sysfs the
value is shifted and scaled appropriately.
Signed-off-by: Chris Packham <chris.pack...@alliedtelesis.co.nz>
---
Changes in v2:
- Simplify as per feedback from Guenter.
- Re-word commit message.
drivers/hwmon/adm9240.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/hwmon/adm9240.c b/drivers/hwmon/adm9240.c
index 98114ce..8d8ede8 100644
--- a/drivers/hwmon/adm9240.c
+++ b/drivers/hwmon/adm9240.c
@@ -197,7 +197,7 @@ static struct adm9240_data *adm9240_update_device(struct
device *dev)
data->temp = ((i2c_smbus_read_byte_data(client,
ADM9240_REG_TEMP) << 8) |
i2c_smbus_read_byte_data(client,
- ADM9240_REG_TEMP_CONF)) / 128;
+ ADM9240_REG_TEMP_CONF));
for (i = 0; i < 2; i++) { /* read fans */
data->fan[i] = i2c_smbus_read_byte_data(client,
@@ -263,7 +263,7 @@ static ssize_t show_temp(struct device *dev, struct
device_attribute *dummy,
char *buf)
{
struct adm9240_data *data = adm9240_update_device(dev);
- return sprintf(buf, "%d\n", data->temp * 500); /* 9-bit value */
+ return sprintf(buf, "%d\n", data->temp / 128 * 500); /* 9-bit value */
}
static ssize_t show_max(struct device *dev, struct device_attribute *devattr,
--
2.10.1
--
To unsubscribe from this list: send the line "unsubscribe linux-hwmon" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
