On 3/21/21 6:07 AM, Lars-Peter Clausen wrote:

On 3/20/21 7:45 AM, Puranjay Mohan wrote:

quoted

TMP117 is a Digital temperature sensor with integrated NV memory.

Add support for tmp117 driver in iio subsystem.

Datasheet:-https://www.ti.com/lit/gpn/tmp117

Signed-off-by: Puranjay Mohan <redacted>

This looks good to me. Just two small bits I overlooked during the 
first review, sorry for that.

quoted

+};
+
[...]
+static int tmp117_read_raw(struct iio_dev *indio_dev,
+        struct iio_chan_spec const *channel, int *val,
+        int *val2, long mask)
+{
+    struct tmp117_data *data = iio_priv(indio_dev);
+    u16 tmp, off;
+
+    switch (mask) {
+    case IIO_CHAN_INFO_RAW:
+        tmp = tmp117_read_reg(data, TMP117_REG_TEMP);
+        *val = tmp;

No need for tmp here. Just directly assign to val.

Actually thinking about this, does the current implementation work 
correctly for negative temperatures?

I think there are two options to fix it. Either cast to s16 or use the 
sign_extend32() function.

Have a look at how the tmp006 driver handles this. It is a good example, 
including the error checking. In general you should check if your I2C 
read failed and return an error in that case rather than a bogus value 
for the measurement. Same for when reading the calibration offset.

Another thing. IIO reports temperature values in milli degrees Celsius. 
I believe in the current implementation the scale is so that it will 
report in degrees Celsius instead.