Jean Delvare wrote: > On Sun, 12 Oct 2008 12:12:19 +0200, Hans de Goede wrote: >> Ira Snyder wrote: >>> Add Linux support for the Linear Technology LTC4245 Multiple Supply Hot >>> Swap controller I2C monitoring interface. >> (...) >> That only leaves one issue, it would be nice to be able to map the currents and >> voltages together by something other then labels, but allas we have no API in >> place for that. We could however try to give them to same numbers. >> >> So what I would like to suggest is to have the following sysfs attributes for >> inputs: >> >> in1_input 12v input voltage (mV) >> in2_input 5v input voltage (mV) >> in3_input 3v input voltage (mV) >> curr1_input 12v amperage (mA) >> curr2_input 12v amperage (mA) > > I guess you mean 5v... > >> curr3_input 12v amperage (mA) > > ... and 3v. > Erm, yes. >> Given that we measure both output voltage and current, I think it would be cool >> to also add power#_input's to the driver, as thats just "output voltage * >> current". I know people will start screaming that we should do things like this >> in userspace, but given the fact that we have no API to match voltages and >> currents, let alone one to do the interesting mapping here, where one current >> corresponds to 2 voltages, and given how easy it is to add these 2 this driver, >> I'm in favor of adding them, so then we would also get: >> >> power1_input 12v power consumption (micro watt) >> power2_input 5v power consumption (micro watt) >> power3_input 3v power consumption (micro watt) >> >> Jean, whats your 2 cents on this ? > > I don't have enough free time these days to afford having an objection. > I am not too happy to see non-independent inputs in sysfs, as there's > no way for the user to know which values are independent and which are > computer, but indeed we lack a good way to express the relations > between different inputs. That's the same problem we had for fan# and > pwm#, or pwm# and temp# for automatic fan speed control. At some point > it might be convenient to introduce virtual sub-devices grouping > together things related items. For now, all we have is > pwm[1-*]_auto_channels_temp to map temperature channels to pwm outputs. > I guess we could do something similar to link voltage and current > channels. > > But then again I do not have enough time to properly think about this > and propose something. So I'd say, do whatever you want, and whoever > really cares will have to do the thinking and the proposal and update > the drivers and libsensors if/as needed. I hear you, but as everyone involved in hwmon seems to be short on time, and as this is the first IC to expose this kind of problems, I think for now its best to just stick with what we have. And add the power#_input attributes to this driver as a service to userspace, as userspace cannot easily find this out itself due to lack of API. >>> Take it easy on me, this is my first hwmon driver :) I'd love >>> suggestions for improvements, however. >> Don't worry, for a first driver it is pretty good :) If you agree with my >> proposed sysfs interface and change the driver to match, I think we can get it >> in to 2.6.28. > > That's a pretty optimistic statement from someone who isn't in charge ;) Erm (I get the hint), yes it is :) Regards, Hans
