APM(4)               OpenBSD Programmer's Manual (MacPPC)               APM(4)

NAME
     apm - advanced power management device interface

SYNOPSIS
     apm0 at adb0

DESCRIPTION
     The apm driver provides an interface which simulates the Advanced Power
     Management (APM) BIOS functions.  The bios functions are translated into
     the appropriate PowerManager requests.  Currently only battery level, AC
     connection, and charging status is available from the apm device.  Sus-
     pend/resume and other power events are NOT YET SUPPORTED.

     Configuration options:

           APMDEBUG    Enable various driver status messages.
           DIAGNOSTIC  Enable debugging messages.
           DEBUG       Enable other debugging messages.

     The apm driver implements the following ioctl(2) calls.  They are defined
     in <machine/apmvar.h>.

     APM_IOC_REJECT
             Not implemented. DO NOT USE.

     APM_IOC_STANDBY
             NOT YET SUPPORTED on macppc (no parameters) Request ``standby''
             mode.

     APM_IOC_SUSPEND
             NOT YET SUPPORTED on macppc (no parameters) Request ``suspend''
             mode.

     APM_IOC_GETPOWER
             (struct apm_power_info) Request the current power state.  The ar-
             gument structure is as follows:

                   struct apm_power_info {
                           u_char battery_state;
                           u_char ac_state;
                           u_char battery_life;
                           u_char spare1;
                           u_int minutes_left;
                           u_int spare2[6];
                   };

             The following values are defined for battery_state:

             APM_BATT_HIGH
                     Battery has a high state of charge.

             APM_BATT_LOW
                     Battery has a low state of charge.

             APM_BATT_CRITICAL
                     Battery has a critical state of charge.

             APM_BATT_CHARGING
                     Battery is not high, low, or critical and is currently
                     charging.

             APM_BATT_UNKNOWN

                     Can not read the current battery state.

             APM_BATTERY_ABSENT
                     No battery installed.

             The following values are defined for ac_state:

             APM_AC_OFF
                     External power not detected.

             APM_AC_ON
                     External power detected.

             APM_AC_BACKUP
                     Backup power in use.

             APM_AC_UNKNOWN
                     External power state unknown.

             The battery_life value contains the estimated percentage of bat-
             tery life available.  100% indicates a full charge.

             The minutes_left value contains the estimated number of minutes
             of battery life remaining.

     APM_IOC_NEXTEVENT
             NOT YET SUPPORTED on macppc (struct apm_event_info) The APM driv-
             er stores up to APM_NEVENTS events.  This was defined as 16 at
             the time this documentation was written.  If the event list is
             full when a new event is detected the new event is lost.
             APM_IOC_NEXTEVENT ioctl returns the next event on the list or
             EAGAIN if the event list is empty.  The format of the returned
             event is:

                   struct apm_event_info {
                           u_int type;
                           u_int index;
                           u_int spare[8];
                   };
             where index is a sequential count of events that can be used to
             check if any events were lost and type is one of:
                   APM_STANDBY_REQ
                   APM_SUSPEND_REQ
                   APM_NORMAL_RESUME
                   APM_CRIT_RESUME
                   APM_BATTERY_LOW
                   APM_POWER_CHANGE
                   APM_UPDATE_TIME
                   APM_CRIT_SUSPEND_REQ
                   APM_USER_STANDBY_REQ
                   APM_USER_SUSPEND_REQ
                   APM_SYS_STANDBY_RESUME

     APM_IOC_DEV_CTL
             NOT YET SUPPORTED on macppc (struct apm_ctl) Allows an applica-
             tion to directly set the operating mode.  The argument structure
             is as follows:

                   struct apm_ctl {
                           u_int dev;
                           u_int mode;
                   };

             dev indicates the device, typically APM_DEV_ALLDEVS.


             mode indicates the desired operating mode.  Possible values are
                   APM_SYS_READY
                   APM_SYS_STANDBY
                   APM_SYS_SUSPEND
                   APM_SYS_OFF
                   APM_LASTREQ_INPROG
                   APM_LASTREQ_REJECTED

     APM_IOC_PRN_CTL
             NOT YET SUPPORTED on macppc (int) This ioctl(2) controls message
             output by the APM driver when a power change event is detected.
             The integer parameter is one of:

             APM_PRINT_ON
                     All power change events result in a message.  This is the
                     normal operating mode for the driver.

             APM_PRINT_OFF
                     Power change event messages are suppressed.

             APM_PRINT_PCT
                     Power change event messages are suppressed unless the es-
                     timated battery life percentage changes.

             However, in no case will power status messages be displayed until
             the battery life goes below the percentage in the sysctl(8) state
             variable machdep.apmwarn. Setting machdep.apmwarn to zero dis-
             ables all warnings regardless of the APM_IOC_PRN_CTL setting.

     NOT YET SUPPORTED on macppc: As noted above, the operation of the APM
     driver can be modified using the machdep.apmwarn sysctl(8) variable.  An-
     other driver modifier is the machdep.apmhalt variable.  When
     machdep.apmhalt is set to 1 the APM power down code is modified in a way
     necessary for correct operation on some systems, mainly IBM laptops.  If
     your system does not power down when given the command halt -p try set-
     ting machdep.apmhalt to 1 using sysctl(8). The variable can be set at
     boot time in sysctl.conf(5).

FILES
     /dev/apm     APM data device.  May only be opened read-only.  May be
                  opened by multiple concurrent users.

     /dev/apmctl  APM control device.  May be opened read-write or write-only.
                  May only be opened by one user at a time.  An attempt to
                  open the file when in use will fail, returning EBUSY.

SEE ALSO
     sysctl.conf(5), apm(8), apmd(8), halt(8), sysctl(8)

HISTORY
     The apm driver source code contains these copyrights:

     Copyright (c) 1995 John T. Kohl. All rights reserved.
     Copyright (C) 1994 by HOSOKAWA Tatsumi <hosokawa@mt.cs.keio.ac.jp>

     ...and has been hacked on by many others since.

BUGS
     Sleep modes and power events are not supported.

OpenBSD 3.0                      July 17, 1998                               3
