On 7/27/23 23:49, Daniel Matyas wrote:
Dear hwmon community,
I developed the driver for the max31827 temperature sensor, but when
doing so I omitted some functionalities of the chip, namely: PEC Error,
Fault Queue, Comp/Int, Alarm Polarity, Resolution, Timeout and PEC
Enable. I did not implement these, because there are no predefined
attributes in the linux kernel which have similar meaning to these
funcionalities.
I recently got a request from the client to implement these
functionalities. I want to use SENSOR_DEVICE_ATTR to implement these. I
did some reading and saw that using debufs is also a possibility.
I would be really greatful, if you could provide me with some advices.
Should I proceed with device attributes defined by me? Should I use
debufs? Maybe there is another and better way...
pec related attributes should be attached to the i2c interface. Other
drivers already do that; look for pec_{show,store}. The same is true
for timeout.
Comp/Int and Alarm polarity are system properties which should be set
via devicetree.
For others I am not sure. Fault Queue also smells like a system property
since normally one would only modify it if a given system requires it
(for example because the sensors are noisy). The same is true for sensor
resolution, though that one is closest for considering a sysfs attribute.
For most sensors, the resolution is closely related to conversion time
and can be handled with that attribute. I think that isn't the case here,
and there are numerous chips where the resolution is configurable, so it
may make sense to consider a sysfs attribute.
Guenter
