Greg KH wrote: >On Wed, May 12, 2004 at 02:12:45PM -0700, Philip Pokorny wrote: > > >>bash can handle bit operations just fine. >> >>bash$ echo $(( 7 & 2 )) >>2 >>bash$ echo $(( 8 & 2 )) >>0 >> >> > >Heh, you can tell I am not a good bash programmer :) > > > >>So that shouldn't be a concern. >> >> > >Ok, nevermind. > > > >>I'd like to make another suggestion. Put meaningful text strings as the >>contents of the _status file: >> >> LOW (for low alarm) >> HIGH (for high alarm) >> FAIL (for diode failure) >> ALARM (for generic alarm) >> HIGH, FAIL (for multiple alarms) >> "" (null string for no alarm) >> >>Then the sensors library and other tools/languages can just "cat" the >>contents to get the status and test for non-null string to see if there >>is an active alarm or not. >> >> > >Ah, I like this even better. We would never need to display more than >one status at a time per device, right? > > I suppose it depends on what you mean. As I said, there is a case like: "ALARM, FAIL" (for multiple alarms) Which could be construed as "more than one status" but they are all alarms for the same parameter so I see this as a single value. One other thing to consider is if individual alarms can be masked (similar to the way interrupts can be masked) then we might want yet another parameter to mask a given alarm. If "ALARM" is individually maskable from "FAIL", then they would need to be split into multiple foo_status parameters with matching foo_status_mask values. For example, the EMC6D100 which is supported by the LM85 driver has seperate status bits for diode faults and over limit conditions. Each status is individually maskable, but only the over/under limit status can generate an interrupt. And you can't tell an over-limit from an under-limit condition unless you check the current input, and limits. temp0_input temp0_alarm_status temp0_alarm_status_mask temp0_fail_status temp0_fail_status_mask temp0_min temp0_max But having to read multiple files to get the complete alarm status for a given input would be annoying. Especially if it means having to read all of (_min_status, _max_status, _crit_status, _fail_status, etc...) :v) -- Philip Pokorny, Director of Engineering Tel: 415-954-2823 Fax: 415-954-2899 Toll Free: 888-PENGUIN PENGUIN COMPUTING, INC. www.penguincomputing.com
