On 10/25/24 6:35 AM, Miclaus, Antoniu wrote: >> ... >> >> See the ad7380 driver as an example of how to impelemt this. [2] >> >> [2]: https://urldefense.com/v3/__https://lore.kernel.org/linux- >> iio/20240530-iio-add-support-for-multiple-scan-types-v3-5- >> cbc4acea2cfa@xxxxxxxxxxxx/__;!!A3Ni8CS0y2Y!4LS7UI11XqIHRgT3ckx76VYn >> CyeikpTumyjO0qDTn7eF7Fd- >> jFFL8yqpYcMAxP_u3VC09bfIAB7gW_rvGoM_sEA$ >> >> Also, I would expect the .sign value to depend on how the >> input is being used. If it is differential or single-ended >> bipolar, then it is signed, but if it is signle-ended unipoloar >> then it is unsiged. >> >> Typically, this is coming from the devicetree because it >> depends on what is wired up to the input. > > This topic is mentioned in the cover letter, maybe not argued enough there. > Yes, the go-to approach is to specify the unipolar/bipolar configuration in the devicetree. > But this is a request from the actual users of the driver: to have the softspan fully > controlled from userspace. That's why the offset and scale implementations were added. > Both these attributes are influencing the softspan. > >>> + }, \ >>> +} >> The cover letter did not get sent, so we did not see this. Still, I have doubts about using the offset attribute for this since a 0 raw value is always 0V for both unipolar and bipolar cases. There is never an offset to apply to the raw value. So I think we will need to find a different way to control this other than the offset attribute.
