| Message ID | 20161004214054.18501-1-chris.packham@alliedtelesis.co.nz (mailing list archive) |
|---|---|
| State | Accepted |
| Headers | show |
On Wed, Oct 05, 2016 at 10:40:54AM +1300, Chris Packham wrote: > 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.packham@alliedtelesis.co.nz> Applied (after removing the extra () in the data->temp assignment). Thanks, Guenter > --- > 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 majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-hwmon" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
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,
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.packham@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(-)