1.\" $OpenBSD: apm.4,v 1.36 2023/01/30 14:43:29 jcs Exp $ 2.\" 3.\" Copyright (c) 1998 Marco S. Hyman 4.\" 5.\" Permission to copy all or part of this material for any purpose is 6.\" granted provided that the above copyright notice and this paragraph 7.\" are duplicated in all copies. THIS SOFTWARE IS PROVIDED ``AS IS'' 8.\" AND WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, WITHOUT 9.\" LIMITATION, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 10.\" FOR A PARTICULAR PURPOSE. 11.\" 12.Dd $Mdocdate: January 30 2023 $ 13.Dt APM 4 i386 14.Os 15.Sh NAME 16.Nm apm 17.Nd advanced power management device interface 18.Sh SYNOPSIS 19.Cd "apm0 at bios0 flags 0x0000" 20.Sh DESCRIPTION 21The 22.Nm 23driver provides an interface to the Advanced Power Management 24.Pq APM 25BIOS functions. 26The driver supports versions 1.0, 1.1, and 1.2 interface specifications. 27.Pp 28This driver also provides an interface to 29.Xr acpi 4 30on some machines. 31.Pp 32The low two bytes of the flags specify the version of the specification 33driver should conform to in binary decimal notation. 34The value of 0x0101 would specify version 1.1 of the interface 35specification to be used. 36.Pp 37The value of 0x10000 specifies whether to leave interrupts enabled 38when calling APM BIOS routines. 39This is needed for some 40.Tn IBM 41laptops, the symptoms are 42hangs and freezes on suspend, stand by, and hibernation activities. 43.Pp 44The value of 0x20000 specifies to swap the bytes of the battery 45life estimation (the DX register) as given from the APM BIOS. 46This is needed for some 47.Tn SONY VAIO 48laptops, such as some 505 models. 49.Pp 50Configuration options: 51.Pp 52.Bl -tag -width DIAGNOSTIC -compact -offset indent 53.It Dv APMDEBUG 54Enable various driver status messages. 55.It Dv DIAGNOSTIC 56Enable debugging messages. 57.It Dv DEBUG 58Enable other debugging messages. 59.El 60.Pp 61The 62.Nm 63driver implements the following 64.Xr ioctl 2 65calls. 66They are defined in 67.In machine/apmvar.h . 68.Bl -tag -width Ds 69.It Dv APM_IOC_REJECT 70.Em Not implemented . DO NOT USE . 71.It Dv APM_IOC_STANDBY 72.Pq Li "no parameters" 73Request 74.Dq standby 75mode. 76.It Dv APM_IOC_SUSPEND 77.Pq Li "no parameters" 78Request 79.Dq suspend 80mode. 81.It Dv APM_IOC_HIBERNATE 82.Pq Li "no parameters" 83Request 84.Dq hibernate 85mode. 86.It Dv APM_IOC_GETPOWER 87.Pq Li "struct apm_power_info" 88Request the current power state. 89The argument structure is as follows: 90.Bd -literal -offset indent 91struct apm_power_info { 92 u_char battery_state; 93 u_char ac_state; 94 u_char battery_life; 95 u_char spare1; 96 u_int minutes_left; 97 u_int spare2[6]; 98}; 99.Ed 100.Pp 101The following values are defined for 102.Va battery_state : 103.Bl -tag -width Ds 104.It Dv APM_BATT_HIGH 105Battery has a high state of charge. 106.It Dv APM_BATT_LOW 107Battery has a low state of charge. 108.It Dv APM_BATT_CRITICAL 109Battery has a critical state of charge. 110.It Dv APM_BATT_CHARGING 111Battery is not high, low, or critical and is currently charging. 112.It Dv APM_BATT_UNKNOWN 113Cannot read the current battery state. 114.It Dv APM_BATTERY_ABSENT 115No battery installed. 116.El 117.Pp 118The following values are defined for 119.Va ac_state : 120.Bl -tag -width Ds 121.It Dv APM_AC_OFF 122External power not detected. 123.It Dv APM_AC_ON 124External power detected. 125.It Dv APM_AC_BACKUP 126Backup power in use. 127.It Dv APM_AC_UNKNOWN 128External power state unknown. 129.El 130.Pp 131The 132.Va battery_life 133value contains the estimated percentage of battery life available. 134100% indicates a full charge. 135.Pp 136The 137.Va minutes_left 138value contains the estimated number of minutes of battery life 139remaining. 140.It Dv APM_IOC_DEV_CTL 141.Pq Li "struct apm_ctl" 142Allows an application to directly set the 143APM operating mode. 144The argument structure is as follows: 145.Bd -literal -offset indent 146struct apm_ctl { 147 u_int dev; 148 u_int mode; 149}; 150.Ed 151.Pp 152.Va dev 153indicates the device, typically 154.Dv APM_DEV_ALLDEVS . 155.Pp 156.Va mode 157indicates the desired operating mode. 158Possible values are 159.Bl -tag -width Ds -compact -offset indent 160.It Dv APM_SYS_READY 161.It Dv APM_SYS_STANDBY 162.It Dv APM_SYS_SUSPEND 163.It Dv APM_SYS_OFF 164.It Dv APM_LASTREQ_INPROG 165.It Dv APM_LASTREQ_REJECTED 166.El 167.It Dv APM_IOC_PRN_CTL 168.Pq Li "int" 169This 170.Xr ioctl 2 171controls message output by the APM 172driver when a power change event is detected. 173The integer parameter is one of: 174.Bl -tag -width Ds 175.It Dv APM_PRINT_ON 176All power change events result in a message. 177This is the normal operating mode for the driver. 178.It Dv APM_PRINT_OFF 179Power change event messages are suppressed. 180.It Dv APM_PRINT_PCT 181Power change event messages are suppressed unless the estimated 182battery life percentage changes. 183.El 184.El 185.Sh FILES 186.Bl -tag -width "/dev/apmctlXXX" 187.It /dev/apm 188Power management data device. 189May only be opened read-only. 190May be opened by multiple concurrent users. 191.It /dev/apmctl 192Power management control device. 193May be opened read-write or write-only. 194May only be opened by one user at a time. 195An attempt to open the file when in use will fail, returning 196.Er EBUSY . 197.El 198.Sh SEE ALSO 199.Xr acpi 4 , 200.Xr intro 4 , 201.Xr apm 8 , 202.Xr apmd 8 , 203.Xr halt 8 204.Sh HISTORY 205The 206.Nm 207driver source code contains these copyrights: 208.Pp 209.Bl -item -compact 210.It 211.Li Copyright (c) 1995 John T. Kohl. All rights reserved. 212.It 213.Li Copyright (C) 1994 by HOSOKAWA Tatsumi <hosokawa@mt.cs.keio.ac.jp> 214.El 215.Pp 216\&...and has been hacked on by many others since. 217.Sh BUGS 218Not all the BIOSes support power down the way we are attempting 219to execute it. 220.Pp 221Not all BIOS vendors even read the specification. 222