On 30/01/2018 at 06:15:18 -0800, Guenter Roeck wrote: > On 01/30/2018 03:40 AM, Denis OSTERLAND wrote: > > Am Dienstag, den 30.01.2018, 11:27 +0100 schrieb Alexandre Belloni: > > > On 29/01/2018 at 13:59:19 -0800, Guenter Roeck wrote: > > > > > > > > On Wed, Jan 24, 2018 at 10:03:33AM +0100, Michael Grzeschik wrote: > > > > [ ... ] > > > > > > > > > > > > > > > > > > > > > > > > > + > > > > > > > diff --git a/Documentation/hwmon/sysfs-interface b/Documentation/hwmon/sysfs-interface > > > > > > > index fc337c317c673..a12b3c2b2a18c 100644 > > > > > > > --- a/Documentation/hwmon/sysfs-interface > > > > > > > +++ b/Documentation/hwmon/sysfs-interface > > > > > > > @@ -702,6 +702,13 @@ intrusion[0-*]_alarm > > > > > > > the user. This is done by writing 0 to the file. Writing > > > > > > > other values is unsupported. > > > > > > > +intrusion[0-*]_timestamp > > > > > > > + Chassis intrusion detection > > > > > > > + YYYY-MM-DD HH:MM:SS UTC (ts.sec): intrusion detected > > > > > > > + RO > > > > > > > + The corresponding timestamp on which the intrustion > > > > > > > + was detected. > > > > > > > + > > > > > > Sneaky. Nack. You don't just add attributes to the ABI because you want it, > > > > > > without serious discussion, and much less so hidden in an RTC driver > > > > > > (and even less as unparseable attribute). > > > > > Right; but it was not meant to be sneaky. I should have stick to my first > > > > > thought and label this patch RFC. Sorry for that. > > > > > > > > > > > > > > > > > In addition to that, I consider the attribute unnecessary. The intrusion > > > > > > already generates an event which should be sufficient for all practical > > > > > > purposes. > > > > > Would it make sense in between the other sysfs attributes of this driver? > > > > > > > > > I don't understand what you mean with that, sorry. > > > > > > > > From an ABI perspective, the attibute doesn't add value since it is > > > > highly device specific (or at least it is the only chip I am aware of > > > > which reports such a time stamp). Feel free to add the attribute to the > > > > driver and document it, but not as part of the hwmon ABI. In that > > > > case I would be inclined to accept it. However, keep in mind that > > > > your version, reporting a human readable date/time, would effectively > > > > preclude it from ever making it into the ABI. > > > > > > > Actually, there are many RTCs that are able to register one or more > > > timestamps. My plan was to add support for that soon but I was not > > > planning to do so in the hwmon ABI as this may be used for something > > > that is not intrusion detection (interval timers for example). > > What would you suggest? > > I think about something like this: > > event[0-*]_timestamp: timestamp in seconds since epoch or empty if not triggered > > event[0-*]_alarm: 1 if event was triggered, else 0; write 0 to clear event > > Sure, that makes sense if the events are not specifically related > to intrusion detection. Question is if there would ever be more than one > or if event_timestamp and event_alarm would be sufficient. > My target is a PCF85363A which supports up to 3 timestamps. SO I'd go for timestamp[0-*]. This would be empty if it never triggered (or the timestamp is invalid) writing anything to that file resets the event. I don't think we need more than one file per timestamp. -- Alexandre Belloni, Free Electrons Embedded Linux and Kernel engineering http://free-electrons.com -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
