On 09/20/11 18:55, Guenter Roeck wrote: > Some hwmon drivers start adding support for alarm attribute notifications and > generate uevents. Standardize the ABI to be used for this purpose. > Perhaps some guidance on when uevents make sense rather than notifications? Also, why would you do both? > Signed-off-by: Guenter Roeck <guenter.roeck@xxxxxxxxxxxx> > --- > v2: Fixed typos. > Added faults to attributes triggering notifications. > Generate uevent on hwmon device kobject. > > Documentation/hwmon/sysfs-interface | 32 ++++++++++++++++++++++++++++++++ > 1 files changed, 32 insertions(+), 0 deletions(-) > > diff --git a/Documentation/hwmon/sysfs-interface b/Documentation/hwmon/sysfs-interface > index e65e7e8..35b09d6 100644 > --- a/Documentation/hwmon/sysfs-interface > +++ b/Documentation/hwmon/sysfs-interface > @@ -97,6 +97,17 @@ update_interval The interval at which the chip will update readings. > Some devices have a variable update rate or interval. > This attribute can be used to change it to the desired value. > > +notification This attribute exists if the driver supports notifications on > + alarm, fault, and trigger attributes. Valid attribute values > + are: > + 0: The driver does not support notifications or uevents. > + 1: The driver supports notifications. > + 2: The driver generates a uevent if an alarm, fault, or trigger > + status changes. > + 3: The driver suports notifications and generates a uevent if > + an alarm, fault, or trigger status changes. > + RO > + > > ************ > * Voltages * > @@ -706,6 +717,27 @@ intrusion[0-*]_beep > RW > > > +Notifications and uevents > +------------------------- > + > +Hwmon drivers may support generating notification on sysfs alarm, fault, and > +trigger attributes. This support is reflected in the existence of the > +"notification" attribute described above. > + > +If a driver supports notifications, applications do not have to manually poll > +alarm, fault, and trigger attributes, but can use poll(2) or epoll(4) instead. > + > +If a driver supports notifications, it shall support it for all alarm and > +trigger attributes, and should support it for all fault attributes. > +Notifications shall be generated for all state transistions (0->1 as well as > +1->0). > + > +In addition to notifications, drivers may also support uevents. If so, a uevent > +shall be generated whenever an alarm or trigger attribute changes its state, and > +should be generated whenever a fault attribute changes its state. The uevent > +shall be generated on the driver's hwmon device kobject. > + > + > sysfs attribute writes interpretation > ------------------------------------- > _______________________________________________ lm-sensors mailing list lm-sensors@xxxxxxxxxxxxxx http://lists.lm-sensors.org/mailman/listinfo/lm-sensors
