In iio.json file, offset data type definition is double
In sol_iio_channel struct, offset data type definition is int
eg:
root@raspberrypi3:/sys/bus/iio/devices/iio:device1# cat in_temp_offset
-4368
So offset should be fixed by int data type.

In iio.json and sol_iio_config, sampling_frequency data type definition is int.
According to investigation, sampling_frequency sometimes be int , sometimes be double
eg:
root@raspberrypi3:/sys/bus/iio/devices/iio:device0# ls
buffer in_anglvel_x_scale in_anglvel_z_scale sampling_frequency_available uevent
dev in_anglvel_y_raw name scan_elements
in_anglvel_scale_available in_anglvel_y_scale power subsystem
in_anglvel_x_raw in_anglvel_z_raw sampling_frequency trigger
root@raspberrypi3:/sys/bus/iio/devices/iio:device0# cat sampling_frequency
100

root@raspberrypi3:/sys/bus/iio/devices/iio:device2# ls
buffer in_magn_sampling_frequency in_magn_z_raw scale_available uevent
dev in_magn_scale name scan_elements
in_magn_meas_conf in_magn_x_raw power subsystem
in_magn_meas_conf_available in_magn_y_raw sampling_frequency_available trigger
root@raspberrypi3:/sys/bus/iio/devices/iio:device2# cat in_magn_sampling_frequency
10.000000
root@raspberrypi3:/sys/bus/iio/devices/iio:device2# cat sampling_frequency_available
0.500000 1.0 2.0 5.0 10.0 20.0 50.0

So I think sampling_frequency should be double.