On Thu, Dec 09, 2010 at 08:58:58AM -0800, Guenter Roeck wrote: > Hi all, > > I am looking through libsensors and the hwmon sysfs ABI to identify and fix > inconsistencies. > > One problem I noticed is powerX_alarm, which is defined as "system is drawing > more power than the cap allows". > > powerX_cap is defined as " ... The *_cap files only appear if the cap is known > to be enforced by hardware". > > Now there are conditions where power limits are defined and supported, > but the hardware does not enforce it. Similar, there are devices reporting power > alarms not associated with cap enforcement. Examples are ltc4215 and PMBus devices. > powerX_alarm is supported by the ltc4215 driver, but there is no _cap attribute, > and the alarm is not associated with a maximum, thus a reported alarm doesn't > really reflect the ABI. > In the ltc4215, the power1_alarm occurs when the output voltage of the chip is outside a certain range. This range is specified by external resistors, specific to each application. They are not required to be a specific value by the hardware. I guess that the ltc4215 driver's use of powerX_alarm doesn't follow the ABI document. In essence, the power1_alarm is connected to the chip's power good output (negated). Should the ABI have a powerX_good or powerX_fail attribute? Ira _______________________________________________ lm-sensors mailing list lm-sensors@xxxxxxxxxxxxxx http://lists.lm-sensors.org/mailman/listinfo/lm-sensors
