2 * APM BIOS driver for Linux
3 * Copyright 1994-2001 Stephen Rothwell (sfr@canb.auug.org.au)
5 * Initial development of this driver was funded by NEC Australia P/L
8 * This program is free software; you can redistribute it and/or modify it
9 * under the terms of the GNU General Public License as published by the
10 * Free Software Foundation; either version 2, or (at your option) any
13 * This program is distributed in the hope that it will be useful, but
14 * WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * General Public License for more details.
18 * October 1995, Rik Faith (faith@cs.unc.edu):
19 * Minor enhancements and updates (to the patch set) for 1.3.x
21 * January 1996, Rik Faith (faith@cs.unc.edu):
22 * Make /proc/apm easy to format (bump driver version)
23 * March 1996, Rik Faith (faith@cs.unc.edu):
24 * Prohibit APM BIOS calls unless apm_enabled.
25 * (Thanks to Ulrich Windl <Ulrich.Windl@rz.uni-regensburg.de>)
26 * April 1996, Stephen Rothwell (sfr@canb.auug.org.au)
28 * May 1996, Version 1.2
29 * Feb 1998, Version 1.3
30 * Feb 1998, Version 1.4
31 * Aug 1998, Version 1.5
32 * Sep 1998, Version 1.6
33 * Nov 1998, Version 1.7
34 * Jan 1999, Version 1.8
35 * Jan 1999, Version 1.9
36 * Oct 1999, Version 1.10
37 * Nov 1999, Version 1.11
38 * Jan 2000, Version 1.12
39 * Feb 2000, Version 1.13
40 * Nov 2000, Version 1.14
41 * Oct 2001, Version 1.15
42 * Jan 2002, Version 1.16
43 * Oct 2002, Version 1.16ac
46 * 0.6b: first version in official kernel, Linux 1.3.46
47 * 0.7: changed /proc/apm format, Linux 1.3.58
48 * 0.8: fixed gcc 2.7.[12] compilation problems, Linux 1.3.59
49 * 0.9: only call bios if bios is present, Linux 1.3.72
50 * 1.0: use fixed device number, consolidate /proc/apm into this file,
52 * 1.1: support user-space standby and suspend, power off after system
53 * halted, Linux 1.3.98
54 * 1.2: When resetting RTC after resume, take care so that the time
55 * is only incorrect by 30-60mS (vs. 1S previously) (Gabor J. Toth
56 * <jtoth@princeton.edu>); improve interaction between
57 * screen-blanking and gpm (Stephen Rothwell); Linux 1.99.4
58 * 1.2a:Simple change to stop mysterious bug reports with SMP also added
59 * levels to the printk calls. APM is not defined for SMP machines.
60 * The new replacment for it is, but Linux doesn't yet support this.
61 * Alan Cox Linux 2.1.55
62 * 1.3: Set up a valid data descriptor 0x40 for buggy BIOS's
63 * 1.4: Upgraded to support APM 1.2. Integrated ThinkPad suspend patch by
64 * Dean Gaudet <dgaudet@arctic.org>.
65 * C. Scott Ananian <cananian@alumni.princeton.edu> Linux 2.1.87
66 * 1.5: Fix segment register reloading (in case of bad segments saved
69 * 1.6: Cope with complier/assembler differences.
70 * Only try to turn off the first display device.
71 * Fix OOPS at power off with no APM BIOS by Jan Echternach
72 * <echter@informatik.uni-rostock.de>
74 * 1.7: Modify driver's cached copy of the disabled/disengaged flags
75 * to reflect current state of APM BIOS.
76 * Chris Rankin <rankinc@bellsouth.net>
77 * Reset interrupt 0 timer to 100Hz after suspend
78 * Chad Miller <cmiller@surfsouth.com>
79 * Add CONFIG_APM_IGNORE_SUSPEND_BOUNCE
80 * Richard Gooch <rgooch@atnf.csiro.au>
81 * Allow boot time disabling of APM
82 * Make boot messages far less verbose by default
85 * 1.8: Add CONFIG_APM_RTC_IS_GMT
86 * Richard Gooch <rgooch@atnf.csiro.au>
87 * change APM_NOINTS to CONFIG_APM_ALLOW_INTS
88 * remove dependency on CONFIG_PROC_FS
90 * 1.9: Fix small typo. <laslo@wodip.opole.pl>
91 * Try to cope with BIOS's that need to have all display
92 * devices blanked and not just the first one.
93 * Ross Paterson <ross@soi.city.ac.uk>
94 * Fix segment limit setting it has always been wrong as
95 * the segments needed to have byte granularity.
96 * Mark a few things __init.
97 * Add hack to allow power off of SMP systems by popular request.
98 * Use CONFIG_SMP instead of __SMP__
99 * Ignore BOUNCES for three seconds.
101 * 1.10: Fix for Thinkpad return code.
102 * Merge 2.2 and 2.3 drivers.
103 * Remove APM dependencies in arch/i386/kernel/process.c
104 * Remove APM dependencies in drivers/char/sysrq.c
105 * Reset time across standby.
106 * Allow more inititialisation on SMP.
107 * Remove CONFIG_APM_POWER_OFF and make it boot time
108 * configurable (default on).
109 * Make debug only a boot time parameter (remove APM_DEBUG).
110 * Try to blank all devices on any error.
111 * 1.11: Remove APM dependencies in drivers/char/console.c
112 * Check nr_running to detect if we are idle (from
113 * Borislav Deianov <borislav@lix.polytechnique.fr>)
114 * Fix for bioses that don't zero the top part of the
115 * entrypoint offset (Mario Sitta <sitta@al.unipmn.it>)
116 * (reported by Panos Katsaloulis <teras@writeme.com>).
117 * Real mode power off patch (Walter Hofmann
118 * <Walter.Hofmann@physik.stud.uni-erlangen.de>).
119 * 1.12: Remove CONFIG_SMP as the compiler will optimize
120 * the code away anyway (smp_num_cpus == 1 in UP)
121 * noted by Artur Skawina <skawina@geocities.com>.
122 * Make power off under SMP work again.
123 * Fix thinko with initial engaging of BIOS.
124 * Make sure power off only happens on CPU 0
125 * (Paul "Rusty" Russell <rusty@rustcorp.com.au>).
126 * Do error notification to user mode if BIOS calls fail.
127 * Move entrypoint offset fix to ...boot/setup.S
128 * where it belongs (Cosmos <gis88564@cis.nctu.edu.tw>).
129 * Remove smp-power-off. SMP users must now specify
130 * "apm=power-off" on the kernel command line. Suggested
131 * by Jim Avera <jima@hal.com>, modified by Alan Cox
132 * <alan@lxorguk.ukuu.org.uk>.
133 * Register the /proc/apm entry even on SMP so that
134 * scripts that check for it before doing power off
135 * work (Jim Avera <jima@hal.com>).
136 * 1.13: Changes for new pm_ interfaces (Andy Henroid
137 * <andy_henroid@yahoo.com>).
138 * Modularize the code.
139 * Fix the Thinkpad (again) :-( (CONFIG_APM_IGNORE_MULTIPLE_SUSPENDS
140 * is now the way life works).
141 * Fix thinko in suspend() (wrong return).
142 * Notify drivers on critical suspend.
143 * Make kapmd absorb more idle time (Pavel Machek <pavel@suse.cz>
145 * Disable interrupts while we are suspended (Andy Henroid
146 * <andy_henroid@yahoo.com> fixed by sfr).
147 * Make power off work on SMP again (Tony Hoyle
148 * <tmh@magenta-logic.com> and <zlatko@iskon.hr>) modified by sfr.
149 * Remove CONFIG_APM_SUSPEND_BOUNCE. The bounce ignore
150 * interval is now configurable.
151 * 1.14: Make connection version persist across module unload/load.
152 * Enable and engage power management earlier.
153 * Disengage power management on module unload.
154 * Changed to use the sysrq-register hack for registering the
155 * power off function called by magic sysrq based upon discussions
156 * in irc://irc.openprojects.net/#kernelnewbies
157 * (Crutcher Dunnavant <crutcher+kernel@datastacks.com>).
158 * Make CONFIG_APM_REAL_MODE_POWER_OFF run time configurable.
159 * (Arjan van de Ven <arjanv@redhat.com>) modified by sfr.
160 * Work around byte swap bug in one of the Vaio's BIOS's
161 * (Marc Boucher <marc@mbsi.ca>).
162 * Exposed the disable flag to dmi so that we can handle known
163 * broken APM (Alan Cox <alan@redhat.com>).
164 * 1.14ac: If the BIOS says "I slowed the CPU down" then don't spin
165 * calling it - instead idle. (Alan Cox <alan@redhat.com>)
166 * If an APM idle fails log it and idle sensibly
167 * 1.15: Don't queue events to clients who open the device O_WRONLY.
168 * Don't expect replies from clients who open the device O_RDONLY.
169 * (Idea from Thomas Hood)
170 * Minor waitqueue cleanups. (John Fremlin <chief@bandits.org>)
171 * 1.16: Fix idle calling. (Andreas Steinmetz <ast@domdv.de> et al.)
172 * Notify listeners of standby or suspend events before notifying
173 * drivers. Return EBUSY to ioctl() if suspend is rejected.
174 * (Russell King <rmk@arm.linux.org.uk> and Thomas Hood)
175 * Ignore first resume after we generate our own resume event
176 * after a suspend (Thomas Hood)
177 * Daemonize now gets rid of our controlling terminal (sfr).
178 * CONFIG_APM_CPU_IDLE now just affects the default value of
179 * idle_threshold (sfr).
180 * Change name of kernel apm daemon (as it no longer idles) (sfr).
181 * 1.16ac: Fix up SMP support somewhat. You can now force SMP on and we
182 * make _all_ APM calls on the CPU#0. Fix unsafe sign bug.
183 * TODO: determine if its "boot CPU" or "CPU0" we want to lock to.
187 * Intel Corporation, Microsoft Corporation. Advanced Power Management
188 * (APM) BIOS Interface Specification, Revision 1.1, September 1993.
189 * Intel Order Number 241704-001. Microsoft Part Number 781-110-X01.
191 * [This document is available free from Intel by calling 800.628.8686 (fax
192 * 916.356.6100) or 800.548.4725; or via anonymous ftp from
193 * ftp://ftp.intel.com/pub/IAL/software_specs/apmv11.doc. It is also
194 * available from Microsoft by calling 206.882.8080.]
197 * Intel Corporation, Microsoft Corporation. Advanced Power Management
198 * (APM) BIOS Interface Specification, Revision 1.2, February 1996.
200 * [This document is available from Microsoft at:
201 * http://www.microsoft.com/hwdev/busbios/amp_12.htm]
204 #include <linux/config.h>
205 #include <linux/module.h>
207 #include <linux/poll.h>
208 #include <linux/types.h>
209 #include <linux/stddef.h>
210 #include <linux/timer.h>
211 #include <linux/fcntl.h>
212 #include <linux/slab.h>
213 #include <linux/stat.h>
214 #include <linux/proc_fs.h>
215 #include <linux/miscdevice.h>
216 #include <linux/apm_bios.h>
217 #include <linux/init.h>
218 #include <linux/time.h>
219 #include <linux/sched.h>
220 #include <linux/pm.h>
221 #include <linux/device.h>
222 #include <linux/kernel.h>
223 #include <linux/smp.h>
224 #include <linux/smp_lock.h>
225 #include <linux/dmi.h>
226 #include <linux/suspend.h>
228 #include <asm/system.h>
229 #include <asm/uaccess.h>
230 #include <asm/desc.h>
231 #include <asm/i8253.h>
233 #include "io_ports.h"
235 extern unsigned long get_cmos_time(void);
236 extern void machine_real_restart(unsigned char *, int);
238 #if defined(CONFIG_APM_DISPLAY_BLANK) && defined(CONFIG_VT)
239 extern int (*console_blank_hook)(int);
243 * The apm_bios device is one of the misc char devices.
244 * This is its minor number.
246 #define APM_MINOR_DEV 134
249 * See Documentation/Config.help for the configuration options.
251 * Various options can be changed at boot time as follows:
252 * (We allow underscores for compatibility with the modules code)
253 * apm=on/off enable/disable APM
254 * [no-]allow[-_]ints allow interrupts during BIOS calls
255 * [no-]broken[-_]psr BIOS has a broken GetPowerStatus call
256 * [no-]realmode[-_]power[-_]off switch to real mode before
258 * [no-]debug log some debugging messages
259 * [no-]power[-_]off power off on shutdown
260 * [no-]smp Use apm even on an SMP box
261 * bounce[-_]interval=<n> number of ticks to ignore suspend
263 * idle[-_]threshold=<n> System idle percentage above which to
264 * make APM BIOS idle calls. Set it to
266 * idle[-_]period=<n> Period (in 1/100s of a second) over
267 * which the idle percentage is
271 /* KNOWN PROBLEM MACHINES:
273 * U: TI 4000M TravelMate: BIOS is *NOT* APM compliant
274 * [Confirmed by TI representative]
275 * ?: ACER 486DX4/75: uses dseg 0040, in violation of APM specification
276 * [Confirmed by BIOS disassembly]
277 * [This may work now ...]
278 * P: Toshiba 1950S: battery life information only gets updated after resume
279 * P: Midwest Micro Soundbook Elite DX2/66 monochrome: screen blanking
280 * broken in BIOS [Reported by Garst R. Reese <reese@isn.net>]
281 * ?: AcerNote-950: oops on reading /proc/apm - workaround is a WIP
282 * Neale Banks <neale@lowendale.com.au> December 2000
284 * Legend: U = unusable with APM patches
285 * P = partially usable with APM patches
289 * Define as 1 to make the driver always call the APM BIOS busy
290 * routine even if the clock was not reported as slowed by the
291 * idle routine. Otherwise, define as 0.
293 #define ALWAYS_CALL_BUSY 1
296 * Define to make the APM BIOS calls zero all data segment registers (so
297 * that an incorrect BIOS implementation will cause a kernel panic if it
298 * tries to write to arbitrary memory).
300 #define APM_ZERO_SEGS
305 * Define to make all _set_limit calls use 64k limits. The APM 1.1 BIOS is
306 * supposed to provide limit information that it recognizes. Many machines
307 * do this correctly, but many others do not restrict themselves to their
308 * claimed limit. When this happens, they will cause a segmentation
309 * violation in the kernel at boot time. Most BIOS's, however, will
310 * respect a 64k limit, so we use that. If you want to be pedantic and
311 * hold your BIOS to its claims, then undefine this.
313 #define APM_RELAX_SEGMENTS
316 * Define to re-initialize the interrupt 0 timer to 100 Hz after a suspend.
317 * This patched by Chad Miller <cmiller@surfsouth.com>, original code by
318 * David Chen <chen@ctpa04.mit.edu>
320 #undef INIT_TIMER_AFTER_SUSPEND
322 #ifdef INIT_TIMER_AFTER_SUSPEND
323 #include <linux/timex.h>
325 #include <linux/delay.h>
329 * Need to poll the APM BIOS every second
331 #define APM_CHECK_TIMEOUT (HZ)
334 * Ignore suspend events for this amount of time after a resume
336 #define DEFAULT_BOUNCE_INTERVAL (3 * HZ)
339 * Maximum number of events stored
341 #define APM_MAX_EVENTS 20
344 * The per-file APM data
348 struct apm_user * next;
349 unsigned int suser: 1;
350 unsigned int writer: 1;
351 unsigned int reader: 1;
352 unsigned int suspend_wait: 1;
354 int suspends_pending;
355 int standbys_pending;
360 apm_event_t events[APM_MAX_EVENTS];
364 * The magic number in apm_user
366 #define APM_BIOS_MAGIC 0x4101
369 * idle percentage above which bios idle calls are done
371 #ifdef CONFIG_APM_CPU_IDLE
372 #define DEFAULT_IDLE_THRESHOLD 95
374 #define DEFAULT_IDLE_THRESHOLD 100
376 #define DEFAULT_IDLE_PERIOD (100 / 3)
382 unsigned long offset;
383 unsigned short segment;
385 static int clock_slowed;
386 static int idle_threshold = DEFAULT_IDLE_THRESHOLD;
387 static int idle_period = DEFAULT_IDLE_PERIOD;
388 static int set_pm_idle;
389 static int suspends_pending;
390 static int standbys_pending;
391 static int ignore_sys_suspend;
392 static int ignore_normal_resume;
393 static int bounce_interval = DEFAULT_BOUNCE_INTERVAL;
395 #ifdef CONFIG_APM_RTC_IS_GMT
396 # define clock_cmos_diff 0
397 # define got_clock_diff 1
399 static long clock_cmos_diff;
400 static int got_clock_diff;
404 static int apm_disabled = -1;
406 static int power_off;
408 static int power_off = 1;
410 #ifdef CONFIG_APM_REAL_MODE_POWER_OFF
411 static int realmode_power_off = 1;
413 static int realmode_power_off;
415 static int exit_kapmd;
416 static int kapmd_running;
417 #ifdef CONFIG_APM_ALLOW_INTS
418 static int allow_ints = 1;
420 static int allow_ints;
422 static int broken_psr;
424 static DECLARE_WAIT_QUEUE_HEAD(apm_waitqueue);
425 static DECLARE_WAIT_QUEUE_HEAD(apm_suspend_waitqueue);
426 static struct apm_user * user_list;
427 static DEFINE_SPINLOCK(user_list_lock);
428 static struct desc_struct bad_bios_desc = { 0, 0x00409200 };
430 static char driver_version[] = "1.16ac"; /* no spaces */
433 * APM event names taken from the APM 1.2 specification. These are
434 * the message codes that the BIOS uses to tell us about events
436 static char * apm_event_name[] = {
442 "power status change",
447 "system standby resume",
448 "capabilities change"
450 #define NR_APM_EVENT_NAME ARRAY_SIZE(apm_event_name)
452 typedef struct lookup_t {
458 * The BIOS returns a set of standard error codes in AX when the
462 static const lookup_t error_table[] = {
463 /* N/A { APM_SUCCESS, "Operation succeeded" }, */
464 { APM_DISABLED, "Power management disabled" },
465 { APM_CONNECTED, "Real mode interface already connected" },
466 { APM_NOT_CONNECTED, "Interface not connected" },
467 { APM_16_CONNECTED, "16 bit interface already connected" },
468 /* N/A { APM_16_UNSUPPORTED, "16 bit interface not supported" }, */
469 { APM_32_CONNECTED, "32 bit interface already connected" },
470 { APM_32_UNSUPPORTED, "32 bit interface not supported" },
471 { APM_BAD_DEVICE, "Unrecognized device ID" },
472 { APM_BAD_PARAM, "Parameter out of range" },
473 { APM_NOT_ENGAGED, "Interface not engaged" },
474 { APM_BAD_FUNCTION, "Function not supported" },
475 { APM_RESUME_DISABLED, "Resume timer disabled" },
476 { APM_BAD_STATE, "Unable to enter requested state" },
477 /* N/A { APM_NO_EVENTS, "No events pending" }, */
478 { APM_NO_ERROR, "BIOS did not set a return code" },
479 { APM_NOT_PRESENT, "No APM present" }
481 #define ERROR_COUNT ARRAY_SIZE(error_table)
484 * apm_error - display an APM error
485 * @str: information string
486 * @err: APM BIOS return code
488 * Write a meaningful log entry to the kernel log in the event of
492 static void apm_error(char *str, int err)
496 for (i = 0; i < ERROR_COUNT; i++)
497 if (error_table[i].key == err) break;
499 printk(KERN_NOTICE "apm: %s: %s\n", str, error_table[i].msg);
501 printk(KERN_NOTICE "apm: %s: unknown error code %#2.2x\n",
506 * Lock APM functionality to physical CPU 0
511 static cpumask_t apm_save_cpus(void)
513 cpumask_t x = current->cpus_allowed;
514 /* Some bioses don't like being called from CPU != 0 */
515 set_cpus_allowed(current, cpumask_of_cpu(0));
516 BUG_ON(smp_processor_id() != 0);
520 static inline void apm_restore_cpus(cpumask_t mask)
522 set_cpus_allowed(current, mask);
528 * No CPU lockdown needed on a uniprocessor
531 #define apm_save_cpus() (current->cpus_allowed)
532 #define apm_restore_cpus(x) (void)(x)
537 * These are the actual BIOS calls. Depending on APM_ZERO_SEGS and
538 * apm_info.allow_ints, we are being really paranoid here! Not only
539 * are interrupts disabled, but all the segment registers (except SS)
540 * are saved and zeroed this means that if the BIOS tries to reference
541 * any data without explicitly loading the segment registers, the kernel
542 * will fault immediately rather than have some unforeseen circumstances
543 * for the rest of the kernel. And it will be very obvious! :-) Doing
544 * this depends on CS referring to the same physical memory as DS so that
545 * DS can be zeroed before the call. Unfortunately, we can't do anything
546 * about the stack segment/pointer. Also, we tell the compiler that
547 * everything could change.
549 * Also, we KNOW that for the non error case of apm_bios_call, there
550 * is no useful data returned in the low order 8 bits of eax.
553 if (apm_info.allow_ints) \
554 local_irq_enable(); \
559 # define APM_DECL_SEGS \
560 unsigned int saved_fs; unsigned int saved_gs;
561 # define APM_DO_SAVE_SEGS \
562 savesegment(fs, saved_fs); savesegment(gs, saved_gs)
563 # define APM_DO_RESTORE_SEGS \
564 loadsegment(fs, saved_fs); loadsegment(gs, saved_gs)
566 # define APM_DECL_SEGS
567 # define APM_DO_SAVE_SEGS
568 # define APM_DO_RESTORE_SEGS
572 * apm_bios_call - Make an APM BIOS 32bit call
573 * @func: APM function to execute
574 * @ebx_in: EBX register for call entry
575 * @ecx_in: ECX register for call entry
576 * @eax: EAX register return
577 * @ebx: EBX register return
578 * @ecx: ECX register return
579 * @edx: EDX register return
580 * @esi: ESI register return
582 * Make an APM call using the 32bit protected mode interface. The
583 * caller is responsible for knowing if APM BIOS is configured and
584 * enabled. This call can disable interrupts for a long period of
585 * time on some laptops. The return value is in AH and the carry
586 * flag is loaded into AL. If there is an error, then the error
587 * code is returned in AH (bits 8-15 of eax) and this function
591 static u8 apm_bios_call(u32 func, u32 ebx_in, u32 ecx_in,
592 u32 *eax, u32 *ebx, u32 *ecx, u32 *edx, u32 *esi)
598 struct desc_struct save_desc_40;
599 struct desc_struct *gdt;
601 cpus = apm_save_cpus();
604 gdt = get_cpu_gdt_table(cpu);
605 save_desc_40 = gdt[0x40 / 8];
606 gdt[0x40 / 8] = bad_bios_desc;
608 local_save_flags(flags);
611 apm_bios_call_asm(func, ebx_in, ecx_in, eax, ebx, ecx, edx, esi);
613 local_irq_restore(flags);
614 gdt[0x40 / 8] = save_desc_40;
616 apm_restore_cpus(cpus);
622 * apm_bios_call_simple - make a simple APM BIOS 32bit call
623 * @func: APM function to invoke
624 * @ebx_in: EBX register value for BIOS call
625 * @ecx_in: ECX register value for BIOS call
626 * @eax: EAX register on return from the BIOS call
628 * Make a BIOS call that does only returns one value, or just status.
629 * If there is an error, then the error code is returned in AH
630 * (bits 8-15 of eax) and this function returns non-zero. This is
631 * used for simpler BIOS operations. This call may hold interrupts
632 * off for a long time on some laptops.
635 static u8 apm_bios_call_simple(u32 func, u32 ebx_in, u32 ecx_in, u32 *eax)
642 struct desc_struct save_desc_40;
643 struct desc_struct *gdt;
645 cpus = apm_save_cpus();
648 gdt = get_cpu_gdt_table(cpu);
649 save_desc_40 = gdt[0x40 / 8];
650 gdt[0x40 / 8] = bad_bios_desc;
652 local_save_flags(flags);
655 error = apm_bios_call_simple_asm(func, ebx_in, ecx_in, eax);
657 local_irq_restore(flags);
658 gdt[0x40 / 8] = save_desc_40;
660 apm_restore_cpus(cpus);
665 * apm_driver_version - APM driver version
666 * @val: loaded with the APM version on return
668 * Retrieve the APM version supported by the BIOS. This is only
669 * supported for APM 1.1 or higher. An error indicates APM 1.0 is
672 * On entry val should point to a value indicating the APM driver
673 * version with the high byte being the major and the low byte the
674 * minor number both in BCD
676 * On return it will hold the BIOS revision supported in the
680 static int apm_driver_version(u_short *val)
684 if (apm_bios_call_simple(APM_FUNC_VERSION, 0, *val, &eax))
685 return (eax >> 8) & 0xff;
691 * apm_get_event - get an APM event from the BIOS
692 * @event: pointer to the event
693 * @info: point to the event information
695 * The APM BIOS provides a polled information for event
696 * reporting. The BIOS expects to be polled at least every second
697 * when events are pending. When a message is found the caller should
698 * poll until no more messages are present. However, this causes
699 * problems on some laptops where a suspend event notification is
700 * not cleared until it is acknowledged.
702 * Additional information is returned in the info pointer, providing
703 * that APM 1.2 is in use. If no messges are pending the value 0x80
704 * is returned (No power management events pending).
707 static int apm_get_event(apm_event_t *event, apm_eventinfo_t *info)
714 if (apm_bios_call(APM_FUNC_GET_EVENT, 0, 0, &eax, &ebx, &ecx,
716 return (eax >> 8) & 0xff;
718 if (apm_info.connection_version < 0x0102)
719 *info = ~0; /* indicate info not valid */
726 * set_power_state - set the power management state
727 * @what: which items to transition
728 * @state: state to transition to
730 * Request an APM change of state for one or more system devices. The
731 * processor state must be transitioned last of all. what holds the
732 * class of device in the upper byte and the device number (0xFF for
733 * all) for the object to be transitioned.
735 * The state holds the state to transition to, which may in fact
736 * be an acceptance of a BIOS requested state change.
739 static int set_power_state(u_short what, u_short state)
743 if (apm_bios_call_simple(APM_FUNC_SET_STATE, what, state, &eax))
744 return (eax >> 8) & 0xff;
749 * set_system_power_state - set system wide power state
750 * @state: which state to enter
752 * Transition the entire system into a new APM power state.
755 static int set_system_power_state(u_short state)
757 return set_power_state(APM_DEVICE_ALL, state);
761 * apm_do_idle - perform power saving
763 * This function notifies the BIOS that the processor is (in the view
764 * of the OS) idle. It returns -1 in the event that the BIOS refuses
765 * to handle the idle request. On a success the function returns 1
766 * if the BIOS did clock slowing or 0 otherwise.
769 static int apm_do_idle(void)
773 if (apm_bios_call_simple(APM_FUNC_IDLE, 0, 0, &eax)) {
774 static unsigned long t;
776 /* This always fails on some SMP boards running UP kernels.
777 * Only report the failure the first 5 times.
781 printk(KERN_DEBUG "apm_do_idle failed (%d)\n",
787 clock_slowed = (apm_info.bios.flags & APM_IDLE_SLOWS_CLOCK) != 0;
792 * apm_do_busy - inform the BIOS the CPU is busy
794 * Request that the BIOS brings the CPU back to full performance.
797 static void apm_do_busy(void)
801 if (clock_slowed || ALWAYS_CALL_BUSY) {
802 (void) apm_bios_call_simple(APM_FUNC_BUSY, 0, 0, &dummy);
808 * If no process has really been interested in
809 * the CPU for some time, we want to call BIOS
810 * power management - we probably want
813 #define IDLE_CALC_LIMIT (HZ * 100)
814 #define IDLE_LEAKY_MAX 16
816 static void (*original_pm_idle)(void);
818 extern void default_idle(void);
821 * apm_cpu_idle - cpu idling for APM capable Linux
823 * This is the idling function the kernel executes when APM is available. It
824 * tries to do BIOS powermanagement based on the average system idle time.
825 * Furthermore it calls the system default idle routine.
828 static void apm_cpu_idle(void)
830 static int use_apm_idle; /* = 0 */
831 static unsigned int last_jiffies; /* = 0 */
832 static unsigned int last_stime; /* = 0 */
834 int apm_idle_done = 0;
835 unsigned int jiffies_since_last_check = jiffies - last_jiffies;
839 if (jiffies_since_last_check > IDLE_CALC_LIMIT) {
841 last_jiffies = jiffies;
842 last_stime = current->stime;
843 } else if (jiffies_since_last_check > idle_period) {
844 unsigned int idle_percentage;
846 idle_percentage = current->stime - last_stime;
847 idle_percentage *= 100;
848 idle_percentage /= jiffies_since_last_check;
849 use_apm_idle = (idle_percentage > idle_threshold);
850 if (apm_info.forbid_idle)
852 last_jiffies = jiffies;
853 last_stime = current->stime;
856 bucket = IDLE_LEAKY_MAX;
858 while (!need_resched()) {
863 switch (apm_do_idle()) {
864 case 0: apm_idle_done = 1;
867 bucket = IDLE_LEAKY_MAX;
875 case 1: apm_idle_done = 1;
877 default: /* BIOS refused */
881 if (original_pm_idle)
885 jiffies_since_last_check = jiffies - last_jiffies;
886 if (jiffies_since_last_check > idle_period)
895 * apm_power_off - ask the BIOS to power off
897 * Handle the power off sequence. This is the one piece of code we
898 * will execute even on SMP machines. In order to deal with BIOS
899 * bugs we support real mode APM BIOS power off calls. We also make
900 * the SMP call on CPU0 as some systems will only honour this call
901 * on their first cpu.
904 static void apm_power_off(void)
906 unsigned char po_bios_call[] = {
907 0xb8, 0x00, 0x10, /* movw $0x1000,ax */
908 0x8e, 0xd0, /* movw ax,ss */
909 0xbc, 0x00, 0xf0, /* movw $0xf000,sp */
910 0xb8, 0x07, 0x53, /* movw $0x5307,ax */
911 0xbb, 0x01, 0x00, /* movw $0x0001,bx */
912 0xb9, 0x03, 0x00, /* movw $0x0003,cx */
913 0xcd, 0x15 /* int $0x15 */
916 /* Some bioses don't like being called from CPU != 0 */
917 if (apm_info.realmode_power_off)
919 (void)apm_save_cpus();
920 machine_real_restart(po_bios_call, sizeof(po_bios_call));
923 (void) set_system_power_state(APM_STATE_OFF);
926 #ifdef CONFIG_APM_DO_ENABLE
929 * apm_enable_power_management - enable BIOS APM power management
930 * @enable: enable yes/no
932 * Enable or disable the APM BIOS power services.
935 static int apm_enable_power_management(int enable)
939 if ((enable == 0) && (apm_info.bios.flags & APM_BIOS_DISENGAGED))
940 return APM_NOT_ENGAGED;
941 if (apm_bios_call_simple(APM_FUNC_ENABLE_PM, APM_DEVICE_BALL,
943 return (eax >> 8) & 0xff;
945 apm_info.bios.flags &= ~APM_BIOS_DISABLED;
947 apm_info.bios.flags |= APM_BIOS_DISABLED;
953 * apm_get_power_status - get current power state
954 * @status: returned status
956 * @life: estimated life
958 * Obtain the current power status from the APM BIOS. We return a
959 * status which gives the rough battery status, and current power
960 * source. The bat value returned give an estimate as a percentage
961 * of life and a status value for the battery. The estimated life
962 * if reported is a lifetime in secodnds/minutes at current powwer
966 static int apm_get_power_status(u_short *status, u_short *bat, u_short *life)
974 if (apm_info.get_power_status_broken)
975 return APM_32_UNSUPPORTED;
976 if (apm_bios_call(APM_FUNC_GET_STATUS, APM_DEVICE_ALL, 0,
977 &eax, &ebx, &ecx, &edx, &dummy))
978 return (eax >> 8) & 0xff;
981 if (apm_info.get_power_status_swabinminutes) {
982 *life = swab16((u16)edx);
990 static int apm_get_battery_status(u_short which, u_short *status,
991 u_short *bat, u_short *life, u_short *nbat)
999 if (apm_info.connection_version < 0x0102) {
1000 /* pretend we only have one battery. */
1002 return APM_BAD_DEVICE;
1004 return apm_get_power_status(status, bat, life);
1007 if (apm_bios_call(APM_FUNC_GET_STATUS, (0x8000 | (which)), 0, &eax,
1008 &ebx, &ecx, &edx, &esi))
1009 return (eax >> 8) & 0xff;
1019 * apm_engage_power_management - enable PM on a device
1020 * @device: identity of device
1023 * Activate or deactive power management on either a specific device
1024 * or the entire system (%APM_DEVICE_ALL).
1027 static int apm_engage_power_management(u_short device, int enable)
1031 if ((enable == 0) && (device == APM_DEVICE_ALL)
1032 && (apm_info.bios.flags & APM_BIOS_DISABLED))
1033 return APM_DISABLED;
1034 if (apm_bios_call_simple(APM_FUNC_ENGAGE_PM, device, enable, &eax))
1035 return (eax >> 8) & 0xff;
1036 if (device == APM_DEVICE_ALL) {
1038 apm_info.bios.flags &= ~APM_BIOS_DISENGAGED;
1040 apm_info.bios.flags |= APM_BIOS_DISENGAGED;
1045 #if defined(CONFIG_APM_DISPLAY_BLANK) && defined(CONFIG_VT)
1048 * apm_console_blank - blank the display
1051 * Attempt to blank the console, firstly by blanking just video device
1052 * zero, and if that fails (some BIOSes don't support it) then it blanks
1053 * all video devices. Typically the BIOS will do laptop backlight and
1054 * monitor powerdown for us.
1057 static int apm_console_blank(int blank)
1062 state = blank ? APM_STATE_STANDBY : APM_STATE_READY;
1063 /* Blank the first display device */
1064 error = set_power_state(0x100, state);
1065 if ((error != APM_SUCCESS) && (error != APM_NO_ERROR)) {
1066 /* try to blank them all instead */
1067 error = set_power_state(0x1ff, state);
1068 if ((error != APM_SUCCESS) && (error != APM_NO_ERROR))
1069 /* try to blank device one instead */
1070 error = set_power_state(0x101, state);
1072 if ((error == APM_SUCCESS) || (error == APM_NO_ERROR))
1074 if (error == APM_NOT_ENGAGED) {
1078 eng_error = apm_engage_power_management(APM_DEVICE_ALL, 1);
1080 apm_error("set display", error);
1081 apm_error("engage interface", eng_error);
1084 return apm_console_blank(blank);
1087 apm_error("set display", error);
1092 static int queue_empty(struct apm_user *as)
1094 return as->event_head == as->event_tail;
1097 static apm_event_t get_queued_event(struct apm_user *as)
1099 as->event_tail = (as->event_tail + 1) % APM_MAX_EVENTS;
1100 return as->events[as->event_tail];
1103 static void queue_event(apm_event_t event, struct apm_user *sender)
1105 struct apm_user * as;
1107 spin_lock(&user_list_lock);
1108 if (user_list == NULL)
1110 for (as = user_list; as != NULL; as = as->next) {
1111 if ((as == sender) || (!as->reader))
1113 as->event_head = (as->event_head + 1) % APM_MAX_EVENTS;
1114 if (as->event_head == as->event_tail) {
1115 static int notified;
1117 if (notified++ == 0)
1118 printk(KERN_ERR "apm: an event queue overflowed\n");
1119 as->event_tail = (as->event_tail + 1) % APM_MAX_EVENTS;
1121 as->events[as->event_head] = event;
1122 if ((!as->suser) || (!as->writer))
1125 case APM_SYS_SUSPEND:
1126 case APM_USER_SUSPEND:
1127 as->suspends_pending++;
1131 case APM_SYS_STANDBY:
1132 case APM_USER_STANDBY:
1133 as->standbys_pending++;
1138 wake_up_interruptible(&apm_waitqueue);
1140 spin_unlock(&user_list_lock);
1143 static void set_time(void)
1145 if (got_clock_diff) { /* Must know time zone in order to set clock */
1146 xtime.tv_sec = get_cmos_time() + clock_cmos_diff;
1151 static void get_time_diff(void)
1153 #ifndef CONFIG_APM_RTC_IS_GMT
1155 * Estimate time zone so that set_time can update the clock
1157 clock_cmos_diff = -get_cmos_time();
1158 clock_cmos_diff += get_seconds();
1163 static void reinit_timer(void)
1165 #ifdef INIT_TIMER_AFTER_SUSPEND
1166 unsigned long flags;
1168 spin_lock_irqsave(&i8253_lock, flags);
1169 /* set the clock to 100 Hz */
1170 outb_p(0x34, PIT_MODE); /* binary, mode 2, LSB/MSB, ch 0 */
1172 outb_p(LATCH & 0xff, PIT_CH0); /* LSB */
1174 outb(LATCH >> 8, PIT_CH0); /* MSB */
1176 spin_unlock_irqrestore(&i8253_lock, flags);
1180 static int suspend(int vetoable)
1183 struct apm_user *as;
1185 if (pm_send_all(PM_SUSPEND, (void *)3)) {
1188 if (apm_info.connection_version > 0x100)
1189 set_system_power_state(APM_STATE_REJECT);
1191 ignore_sys_suspend = 0;
1192 printk(KERN_WARNING "apm: suspend was vetoed.\n");
1195 printk(KERN_CRIT "apm: suspend was vetoed, but suspending anyway.\n");
1198 device_suspend(PMSG_SUSPEND);
1199 local_irq_disable();
1200 device_power_down(PMSG_SUSPEND);
1202 /* serialize with the timer interrupt */
1203 write_seqlock(&xtime_lock);
1205 /* protect against access to timer chip registers */
1206 spin_lock(&i8253_lock);
1210 * Irq spinlock must be dropped around set_system_power_state.
1211 * We'll undo any timer changes due to interrupts below.
1213 spin_unlock(&i8253_lock);
1214 write_sequnlock(&xtime_lock);
1217 save_processor_state();
1218 err = set_system_power_state(APM_STATE_SUSPEND);
1219 ignore_normal_resume = 1;
1220 restore_processor_state();
1222 local_irq_disable();
1223 write_seqlock(&xtime_lock);
1224 spin_lock(&i8253_lock);
1228 spin_unlock(&i8253_lock);
1229 write_sequnlock(&xtime_lock);
1231 if (err == APM_NO_ERROR)
1233 if (err != APM_SUCCESS)
1234 apm_error("suspend", err);
1235 err = (err == APM_SUCCESS) ? 0 : -EIO;
1239 pm_send_all(PM_RESUME, (void *)0);
1240 queue_event(APM_NORMAL_RESUME, NULL);
1242 spin_lock(&user_list_lock);
1243 for (as = user_list; as != NULL; as = as->next) {
1244 as->suspend_wait = 0;
1245 as->suspend_result = err;
1247 spin_unlock(&user_list_lock);
1248 wake_up_interruptible(&apm_suspend_waitqueue);
1252 static void standby(void)
1256 local_irq_disable();
1257 device_power_down(PMSG_SUSPEND);
1258 /* serialize with the timer interrupt */
1259 write_seqlock(&xtime_lock);
1260 /* If needed, notify drivers here */
1262 write_sequnlock(&xtime_lock);
1265 err = set_system_power_state(APM_STATE_STANDBY);
1266 if ((err != APM_SUCCESS) && (err != APM_NO_ERROR))
1267 apm_error("standby", err);
1269 local_irq_disable();
1274 static apm_event_t get_event(void)
1278 apm_eventinfo_t info;
1280 static int notified;
1282 /* we don't use the eventinfo */
1283 error = apm_get_event(&event, &info);
1284 if (error == APM_SUCCESS)
1287 if ((error != APM_NO_EVENTS) && (notified++ == 0))
1288 apm_error("get_event", error);
1293 static void check_events(void)
1296 static unsigned long last_resume;
1297 static int ignore_bounce;
1299 while ((event = get_event()) != 0) {
1301 if (event <= NR_APM_EVENT_NAME)
1302 printk(KERN_DEBUG "apm: received %s notify\n",
1303 apm_event_name[event - 1]);
1305 printk(KERN_DEBUG "apm: received unknown "
1306 "event 0x%02x\n", event);
1309 && ((jiffies - last_resume) > bounce_interval))
1313 case APM_SYS_STANDBY:
1314 case APM_USER_STANDBY:
1315 queue_event(event, NULL);
1316 if (standbys_pending <= 0)
1320 case APM_USER_SUSPEND:
1321 #ifdef CONFIG_APM_IGNORE_USER_SUSPEND
1322 if (apm_info.connection_version > 0x100)
1323 set_system_power_state(APM_STATE_REJECT);
1326 case APM_SYS_SUSPEND:
1327 if (ignore_bounce) {
1328 if (apm_info.connection_version > 0x100)
1329 set_system_power_state(APM_STATE_REJECT);
1333 * If we are already processing a SUSPEND,
1334 * then further SUSPEND events from the BIOS
1335 * will be ignored. We also return here to
1336 * cope with the fact that the Thinkpads keep
1337 * sending a SUSPEND event until something else
1340 if (ignore_sys_suspend)
1342 ignore_sys_suspend = 1;
1343 queue_event(event, NULL);
1344 if (suspends_pending <= 0)
1348 case APM_NORMAL_RESUME:
1349 case APM_CRITICAL_RESUME:
1350 case APM_STANDBY_RESUME:
1351 ignore_sys_suspend = 0;
1352 last_resume = jiffies;
1354 if ((event != APM_NORMAL_RESUME)
1355 || (ignore_normal_resume == 0)) {
1356 write_seqlock_irq(&xtime_lock);
1358 write_sequnlock_irq(&xtime_lock);
1360 pm_send_all(PM_RESUME, (void *)0);
1361 queue_event(event, NULL);
1363 ignore_normal_resume = 0;
1366 case APM_CAPABILITY_CHANGE:
1367 case APM_LOW_BATTERY:
1368 case APM_POWER_STATUS_CHANGE:
1369 queue_event(event, NULL);
1370 /* If needed, notify drivers here */
1373 case APM_UPDATE_TIME:
1374 write_seqlock_irq(&xtime_lock);
1376 write_sequnlock_irq(&xtime_lock);
1379 case APM_CRITICAL_SUSPEND:
1381 * We are not allowed to reject a critical suspend.
1389 static void apm_event_handler(void)
1391 static int pending_count = 4;
1394 if ((standbys_pending > 0) || (suspends_pending > 0)) {
1395 if ((apm_info.connection_version > 0x100) &&
1396 (pending_count-- <= 0)) {
1399 printk(KERN_DEBUG "apm: setting state busy\n");
1400 err = set_system_power_state(APM_STATE_BUSY);
1402 apm_error("busy", err);
1410 * This is the APM thread main loop.
1413 static void apm_mainloop(void)
1415 DECLARE_WAITQUEUE(wait, current);
1417 add_wait_queue(&apm_waitqueue, &wait);
1418 set_current_state(TASK_INTERRUPTIBLE);
1420 schedule_timeout(APM_CHECK_TIMEOUT);
1424 * Ok, check all events, check for idle (and mark us sleeping
1425 * so as not to count towards the load average)..
1427 set_current_state(TASK_INTERRUPTIBLE);
1428 apm_event_handler();
1430 remove_wait_queue(&apm_waitqueue, &wait);
1433 static int check_apm_user(struct apm_user *as, const char *func)
1435 if ((as == NULL) || (as->magic != APM_BIOS_MAGIC)) {
1436 printk(KERN_ERR "apm: %s passed bad filp\n", func);
1442 static ssize_t do_read(struct file *fp, char __user *buf, size_t count, loff_t *ppos)
1444 struct apm_user * as;
1448 as = fp->private_data;
1449 if (check_apm_user(as, "read"))
1451 if ((int)count < sizeof(apm_event_t))
1453 if ((queue_empty(as)) && (fp->f_flags & O_NONBLOCK))
1455 wait_event_interruptible(apm_waitqueue, !queue_empty(as));
1457 while ((i >= sizeof(event)) && !queue_empty(as)) {
1458 event = get_queued_event(as);
1459 if (copy_to_user(buf, &event, sizeof(event))) {
1465 case APM_SYS_SUSPEND:
1466 case APM_USER_SUSPEND:
1467 as->suspends_read++;
1470 case APM_SYS_STANDBY:
1471 case APM_USER_STANDBY:
1472 as->standbys_read++;
1475 buf += sizeof(event);
1480 if (signal_pending(current))
1481 return -ERESTARTSYS;
1485 static unsigned int do_poll(struct file *fp, poll_table * wait)
1487 struct apm_user * as;
1489 as = fp->private_data;
1490 if (check_apm_user(as, "poll"))
1492 poll_wait(fp, &apm_waitqueue, wait);
1493 if (!queue_empty(as))
1494 return POLLIN | POLLRDNORM;
1498 static int do_ioctl(struct inode * inode, struct file *filp,
1499 u_int cmd, u_long arg)
1501 struct apm_user * as;
1503 as = filp->private_data;
1504 if (check_apm_user(as, "ioctl"))
1506 if ((!as->suser) || (!as->writer))
1509 case APM_IOC_STANDBY:
1510 if (as->standbys_read > 0) {
1511 as->standbys_read--;
1512 as->standbys_pending--;
1515 queue_event(APM_USER_STANDBY, as);
1516 if (standbys_pending <= 0)
1519 case APM_IOC_SUSPEND:
1520 if (as->suspends_read > 0) {
1521 as->suspends_read--;
1522 as->suspends_pending--;
1525 queue_event(APM_USER_SUSPEND, as);
1526 if (suspends_pending <= 0) {
1529 as->suspend_wait = 1;
1530 wait_event_interruptible(apm_suspend_waitqueue,
1531 as->suspend_wait == 0);
1532 return as->suspend_result;
1541 static int do_release(struct inode * inode, struct file * filp)
1543 struct apm_user * as;
1545 as = filp->private_data;
1546 if (check_apm_user(as, "release"))
1548 filp->private_data = NULL;
1549 if (as->standbys_pending > 0) {
1550 standbys_pending -= as->standbys_pending;
1551 if (standbys_pending <= 0)
1554 if (as->suspends_pending > 0) {
1555 suspends_pending -= as->suspends_pending;
1556 if (suspends_pending <= 0)
1559 spin_lock(&user_list_lock);
1560 if (user_list == as)
1561 user_list = as->next;
1563 struct apm_user * as1;
1565 for (as1 = user_list;
1566 (as1 != NULL) && (as1->next != as);
1570 printk(KERN_ERR "apm: filp not in user list\n");
1572 as1->next = as->next;
1574 spin_unlock(&user_list_lock);
1579 static int do_open(struct inode * inode, struct file * filp)
1581 struct apm_user * as;
1583 as = (struct apm_user *)kmalloc(sizeof(*as), GFP_KERNEL);
1585 printk(KERN_ERR "apm: cannot allocate struct of size %d bytes\n",
1589 as->magic = APM_BIOS_MAGIC;
1590 as->event_tail = as->event_head = 0;
1591 as->suspends_pending = as->standbys_pending = 0;
1592 as->suspends_read = as->standbys_read = 0;
1594 * XXX - this is a tiny bit broken, when we consider BSD
1595 * process accounting. If the device is opened by root, we
1596 * instantly flag that we used superuser privs. Who knows,
1597 * we might close the device immediately without doing a
1598 * privileged operation -- cevans
1600 as->suser = capable(CAP_SYS_ADMIN);
1601 as->writer = (filp->f_mode & FMODE_WRITE) == FMODE_WRITE;
1602 as->reader = (filp->f_mode & FMODE_READ) == FMODE_READ;
1603 spin_lock(&user_list_lock);
1604 as->next = user_list;
1606 spin_unlock(&user_list_lock);
1607 filp->private_data = as;
1611 static int apm_get_info(char *buf, char **start, off_t fpos, int length)
1618 unsigned short ac_line_status = 0xff;
1619 unsigned short battery_status = 0xff;
1620 unsigned short battery_flag = 0xff;
1621 int percentage = -1;
1622 int time_units = -1;
1627 if ((num_online_cpus() == 1) &&
1628 !(error = apm_get_power_status(&bx, &cx, &dx))) {
1629 ac_line_status = (bx >> 8) & 0xff;
1630 battery_status = bx & 0xff;
1631 if ((cx & 0xff) != 0xff)
1632 percentage = cx & 0xff;
1634 if (apm_info.connection_version > 0x100) {
1635 battery_flag = (cx >> 8) & 0xff;
1637 units = (dx & 0x8000) ? "min" : "sec";
1638 time_units = dx & 0x7fff;
1642 /* Arguments, with symbols from linux/apm_bios.h. Information is
1643 from the Get Power Status (0x0a) call unless otherwise noted.
1645 0) Linux driver version (this will change if format changes)
1646 1) APM BIOS Version. Usually 1.0, 1.1 or 1.2.
1647 2) APM flags from APM Installation Check (0x00):
1648 bit 0: APM_16_BIT_SUPPORT
1649 bit 1: APM_32_BIT_SUPPORT
1650 bit 2: APM_IDLE_SLOWS_CLOCK
1651 bit 3: APM_BIOS_DISABLED
1652 bit 4: APM_BIOS_DISENGAGED
1656 0x02: On backup power (BIOS >= 1.1 only)
1663 0x04: Selected battery not present (BIOS >= 1.2 only)
1670 bit 7: No system battery
1672 6) Remaining battery life (percentage of charge):
1675 7) Remaining battery life (time units):
1676 Number of remaining minutes or seconds
1678 8) min = minutes; sec = seconds */
1680 p += sprintf(p, "%s %d.%d 0x%02x 0x%02x 0x%02x 0x%02x %d%% %d %s\n",
1682 (apm_info.bios.version >> 8) & 0xff,
1683 apm_info.bios.version & 0xff,
1684 apm_info.bios.flags,
1695 static int apm(void *unused)
1708 current->flags |= PF_NOFREEZE;
1712 * This is to avoid random crashes at boot time during initialization
1713 * on SMP systems in case of "apm=power-off" mode. Seen on ASUS A7M266D.
1714 * Some bioses don't like being called from CPU != 0.
1715 * Method suggested by Ingo Molnar.
1717 set_cpus_allowed(current, cpumask_of_cpu(0));
1718 BUG_ON(smp_processor_id() != 0);
1721 if (apm_info.connection_version == 0) {
1722 apm_info.connection_version = apm_info.bios.version;
1723 if (apm_info.connection_version > 0x100) {
1725 * We only support BIOSs up to version 1.2
1727 if (apm_info.connection_version > 0x0102)
1728 apm_info.connection_version = 0x0102;
1729 error = apm_driver_version(&apm_info.connection_version);
1730 if (error != APM_SUCCESS) {
1731 apm_error("driver version", error);
1732 /* Fall back to an APM 1.0 connection. */
1733 apm_info.connection_version = 0x100;
1739 printk(KERN_INFO "apm: Connection version %d.%d\n",
1740 (apm_info.connection_version >> 8) & 0xff,
1741 apm_info.connection_version & 0xff);
1743 #ifdef CONFIG_APM_DO_ENABLE
1744 if (apm_info.bios.flags & APM_BIOS_DISABLED) {
1746 * This call causes my NEC UltraLite Versa 33/C to hang if it
1747 * is booted with PM disabled but not in the docking station.
1750 error = apm_enable_power_management(1);
1752 apm_error("enable power management", error);
1758 if ((apm_info.bios.flags & APM_BIOS_DISENGAGED)
1759 && (apm_info.connection_version > 0x0100)) {
1760 error = apm_engage_power_management(APM_DEVICE_ALL, 1);
1762 apm_error("engage power management", error);
1767 if (debug && (num_online_cpus() == 1 || smp )) {
1768 error = apm_get_power_status(&bx, &cx, &dx);
1770 printk(KERN_INFO "apm: power status not available\n");
1772 switch ((bx >> 8) & 0xff) {
1773 case 0: power_stat = "off line"; break;
1774 case 1: power_stat = "on line"; break;
1775 case 2: power_stat = "on backup power"; break;
1776 default: power_stat = "unknown"; break;
1778 switch (bx & 0xff) {
1779 case 0: bat_stat = "high"; break;
1780 case 1: bat_stat = "low"; break;
1781 case 2: bat_stat = "critical"; break;
1782 case 3: bat_stat = "charging"; break;
1783 default: bat_stat = "unknown"; break;
1786 "apm: AC %s, battery status %s, battery life ",
1787 power_stat, bat_stat);
1788 if ((cx & 0xff) == 0xff)
1789 printk("unknown\n");
1791 printk("%d%%\n", cx & 0xff);
1792 if (apm_info.connection_version > 0x100) {
1794 "apm: battery flag 0x%02x, battery life ",
1797 printk("unknown\n");
1799 printk("%d %s\n", dx & 0x7fff,
1801 "minutes" : "seconds");
1806 /* Install our power off handler.. */
1808 pm_power_off = apm_power_off;
1810 if (num_online_cpus() == 1 || smp) {
1811 #if defined(CONFIG_APM_DISPLAY_BLANK) && defined(CONFIG_VT)
1812 console_blank_hook = apm_console_blank;
1815 #if defined(CONFIG_APM_DISPLAY_BLANK) && defined(CONFIG_VT)
1816 console_blank_hook = NULL;
1825 static int __init apm_setup(char *str)
1829 while ((str != NULL) && (*str != '\0')) {
1830 if (strncmp(str, "off", 3) == 0)
1832 if (strncmp(str, "on", 2) == 0)
1834 if ((strncmp(str, "bounce-interval=", 16) == 0) ||
1835 (strncmp(str, "bounce_interval=", 16) == 0))
1836 bounce_interval = simple_strtol(str + 16, NULL, 0);
1837 if ((strncmp(str, "idle-threshold=", 15) == 0) ||
1838 (strncmp(str, "idle_threshold=", 15) == 0))
1839 idle_threshold = simple_strtol(str + 15, NULL, 0);
1840 if ((strncmp(str, "idle-period=", 12) == 0) ||
1841 (strncmp(str, "idle_period=", 12) == 0))
1842 idle_period = simple_strtol(str + 12, NULL, 0);
1843 invert = (strncmp(str, "no-", 3) == 0) ||
1844 (strncmp(str, "no_", 3) == 0);
1847 if (strncmp(str, "debug", 5) == 0)
1849 if ((strncmp(str, "power-off", 9) == 0) ||
1850 (strncmp(str, "power_off", 9) == 0))
1851 power_off = !invert;
1852 if (strncmp(str, "smp", 3) == 0)
1855 idle_threshold = 100;
1857 if ((strncmp(str, "allow-ints", 10) == 0) ||
1858 (strncmp(str, "allow_ints", 10) == 0))
1859 apm_info.allow_ints = !invert;
1860 if ((strncmp(str, "broken-psr", 10) == 0) ||
1861 (strncmp(str, "broken_psr", 10) == 0))
1862 apm_info.get_power_status_broken = !invert;
1863 if ((strncmp(str, "realmode-power-off", 18) == 0) ||
1864 (strncmp(str, "realmode_power_off", 18) == 0))
1865 apm_info.realmode_power_off = !invert;
1866 str = strchr(str, ',');
1868 str += strspn(str, ", \t");
1873 __setup("apm=", apm_setup);
1876 static struct file_operations apm_bios_fops = {
1877 .owner = THIS_MODULE,
1882 .release = do_release,
1885 static struct miscdevice apm_device = {
1892 /* Simple "print if true" callback */
1893 static int __init print_if_true(struct dmi_system_id *d)
1895 printk("%s\n", d->ident);
1900 * Some Bioses enable the PS/2 mouse (touchpad) at resume, even if it was
1901 * disabled before the suspend. Linux used to get terribly confused by that.
1903 static int __init broken_ps2_resume(struct dmi_system_id *d)
1905 printk(KERN_INFO "%s machine detected. Mousepad Resume Bug workaround hopefully not needed.\n", d->ident);
1909 /* Some bioses have a broken protected mode poweroff and need to use realmode */
1910 static int __init set_realmode_power_off(struct dmi_system_id *d)
1912 if (apm_info.realmode_power_off == 0) {
1913 apm_info.realmode_power_off = 1;
1914 printk(KERN_INFO "%s bios detected. Using realmode poweroff only.\n", d->ident);
1919 /* Some laptops require interrupts to be enabled during APM calls */
1920 static int __init set_apm_ints(struct dmi_system_id *d)
1922 if (apm_info.allow_ints == 0) {
1923 apm_info.allow_ints = 1;
1924 printk(KERN_INFO "%s machine detected. Enabling interrupts during APM calls.\n", d->ident);
1929 /* Some APM bioses corrupt memory or just plain do not work */
1930 static int __init apm_is_horked(struct dmi_system_id *d)
1932 if (apm_info.disabled == 0) {
1933 apm_info.disabled = 1;
1934 printk(KERN_INFO "%s machine detected. Disabling APM.\n", d->ident);
1939 static int __init apm_is_horked_d850md(struct dmi_system_id *d)
1941 if (apm_info.disabled == 0) {
1942 apm_info.disabled = 1;
1943 printk(KERN_INFO "%s machine detected. Disabling APM.\n", d->ident);
1944 printk(KERN_INFO "This bug is fixed in bios P15 which is available for \n");
1945 printk(KERN_INFO "download from support.intel.com \n");
1950 /* Some APM bioses hang on APM idle calls */
1951 static int __init apm_likes_to_melt(struct dmi_system_id *d)
1953 if (apm_info.forbid_idle == 0) {
1954 apm_info.forbid_idle = 1;
1955 printk(KERN_INFO "%s machine detected. Disabling APM idle calls.\n", d->ident);
1961 * Check for clue free BIOS implementations who use
1962 * the following QA technique
1964 * [ Write BIOS Code ]<------
1966 * < Does it Compile >----N--
1968 * < Does it Boot Win98 >-N--
1972 * Phoenix A04 08/24/2000 is known bad (Dell Inspiron 5000e)
1973 * Phoenix A07 09/29/2000 is known good (Dell Inspiron 5000)
1975 static int __init broken_apm_power(struct dmi_system_id *d)
1977 apm_info.get_power_status_broken = 1;
1978 printk(KERN_WARNING "BIOS strings suggest APM bugs, disabling power status reporting.\n");
1983 * This bios swaps the APM minute reporting bytes over (Many sony laptops
1984 * have this problem).
1986 static int __init swab_apm_power_in_minutes(struct dmi_system_id *d)
1988 apm_info.get_power_status_swabinminutes = 1;
1989 printk(KERN_WARNING "BIOS strings suggest APM reports battery life in minutes and wrong byte order.\n");
1993 static struct dmi_system_id __initdata apm_dmi_table[] = {
1996 KERN_WARNING "IBM T23 - BIOS 1.03b+ and controller firmware 1.02+ may be needed for Linux APM.",
1997 { DMI_MATCH(DMI_SYS_VENDOR, "IBM"),
1998 DMI_MATCH(DMI_BIOS_VERSION, "1AET38WW (1.01b)"), },
2000 { /* Handle problems with APM on the C600 */
2001 broken_ps2_resume, "Dell Latitude C600",
2002 { DMI_MATCH(DMI_SYS_VENDOR, "Dell"),
2003 DMI_MATCH(DMI_PRODUCT_NAME, "Latitude C600"), },
2005 { /* Allow interrupts during suspend on Dell Latitude laptops*/
2006 set_apm_ints, "Dell Latitude",
2007 { DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
2008 DMI_MATCH(DMI_PRODUCT_NAME, "Latitude C510"), }
2011 apm_is_horked, "Dell Inspiron 2500",
2012 { DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
2013 DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 2500"),
2014 DMI_MATCH(DMI_BIOS_VENDOR,"Phoenix Technologies LTD"),
2015 DMI_MATCH(DMI_BIOS_VERSION,"A11"), },
2017 { /* Allow interrupts during suspend on Dell Inspiron laptops*/
2018 set_apm_ints, "Dell Inspiron", {
2019 DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
2020 DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 4000"), },
2022 { /* Handle problems with APM on Inspiron 5000e */
2023 broken_apm_power, "Dell Inspiron 5000e",
2024 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2025 DMI_MATCH(DMI_BIOS_VERSION, "A04"),
2026 DMI_MATCH(DMI_BIOS_DATE, "08/24/2000"), },
2028 { /* Handle problems with APM on Inspiron 2500 */
2029 broken_apm_power, "Dell Inspiron 2500",
2030 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2031 DMI_MATCH(DMI_BIOS_VERSION, "A12"),
2032 DMI_MATCH(DMI_BIOS_DATE, "02/04/2002"), },
2035 apm_is_horked, "Dell Dimension 4100",
2036 { DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
2037 DMI_MATCH(DMI_PRODUCT_NAME, "XPS-Z"),
2038 DMI_MATCH(DMI_BIOS_VENDOR,"Intel Corp."),
2039 DMI_MATCH(DMI_BIOS_VERSION,"A11"), },
2041 { /* Allow interrupts during suspend on Compaq Laptops*/
2042 set_apm_ints, "Compaq 12XL125",
2043 { DMI_MATCH(DMI_SYS_VENDOR, "Compaq"),
2044 DMI_MATCH(DMI_PRODUCT_NAME, "Compaq PC"),
2045 DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2046 DMI_MATCH(DMI_BIOS_VERSION,"4.06"), },
2048 { /* Allow interrupts during APM or the clock goes slow */
2049 set_apm_ints, "ASUSTeK",
2050 { DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK Computer Inc."),
2051 DMI_MATCH(DMI_PRODUCT_NAME, "L8400K series Notebook PC"), },
2053 { /* APM blows on shutdown */
2054 apm_is_horked, "ABIT KX7-333[R]",
2055 { DMI_MATCH(DMI_BOARD_VENDOR, "ABIT"),
2056 DMI_MATCH(DMI_BOARD_NAME, "VT8367-8233A (KX7-333[R])"), },
2059 apm_is_horked, "Trigem Delhi3",
2060 { DMI_MATCH(DMI_SYS_VENDOR, "TriGem Computer, Inc"),
2061 DMI_MATCH(DMI_PRODUCT_NAME, "Delhi3"), },
2064 apm_is_horked, "Fujitsu-Siemens",
2065 { DMI_MATCH(DMI_BIOS_VENDOR, "hoenix/FUJITSU SIEMENS"),
2066 DMI_MATCH(DMI_BIOS_VERSION, "Version1.01"), },
2069 apm_is_horked_d850md, "Intel D850MD",
2070 { DMI_MATCH(DMI_BIOS_VENDOR, "Intel Corp."),
2071 DMI_MATCH(DMI_BIOS_VERSION, "MV85010A.86A.0016.P07.0201251536"), },
2074 apm_is_horked, "Intel D810EMO",
2075 { DMI_MATCH(DMI_BIOS_VENDOR, "Intel Corp."),
2076 DMI_MATCH(DMI_BIOS_VERSION, "MO81010A.86A.0008.P04.0004170800"), },
2079 apm_is_horked, "Dell XPS-Z",
2080 { DMI_MATCH(DMI_BIOS_VENDOR, "Intel Corp."),
2081 DMI_MATCH(DMI_BIOS_VERSION, "A11"),
2082 DMI_MATCH(DMI_PRODUCT_NAME, "XPS-Z"), },
2085 apm_is_horked, "Sharp PC-PJ/AX",
2086 { DMI_MATCH(DMI_SYS_VENDOR, "SHARP"),
2087 DMI_MATCH(DMI_PRODUCT_NAME, "PC-PJ/AX"),
2088 DMI_MATCH(DMI_BIOS_VENDOR,"SystemSoft"),
2089 DMI_MATCH(DMI_BIOS_VERSION,"Version R2.08"), },
2092 apm_is_horked, "Dell Inspiron 2500",
2093 { DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
2094 DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 2500"),
2095 DMI_MATCH(DMI_BIOS_VENDOR,"Phoenix Technologies LTD"),
2096 DMI_MATCH(DMI_BIOS_VERSION,"A11"), },
2098 { /* APM idle hangs */
2099 apm_likes_to_melt, "Jabil AMD",
2100 { DMI_MATCH(DMI_BIOS_VENDOR, "American Megatrends Inc."),
2101 DMI_MATCH(DMI_BIOS_VERSION, "0AASNP06"), },
2103 { /* APM idle hangs */
2104 apm_likes_to_melt, "AMI Bios",
2105 { DMI_MATCH(DMI_BIOS_VENDOR, "American Megatrends Inc."),
2106 DMI_MATCH(DMI_BIOS_VERSION, "0AASNP05"), },
2108 { /* Handle problems with APM on Sony Vaio PCG-N505X(DE) */
2109 swab_apm_power_in_minutes, "Sony VAIO",
2110 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2111 DMI_MATCH(DMI_BIOS_VERSION, "R0206H"),
2112 DMI_MATCH(DMI_BIOS_DATE, "08/23/99"), },
2114 { /* Handle problems with APM on Sony Vaio PCG-N505VX */
2115 swab_apm_power_in_minutes, "Sony VAIO",
2116 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2117 DMI_MATCH(DMI_BIOS_VERSION, "W2K06H0"),
2118 DMI_MATCH(DMI_BIOS_DATE, "02/03/00"), },
2120 { /* Handle problems with APM on Sony Vaio PCG-XG29 */
2121 swab_apm_power_in_minutes, "Sony VAIO",
2122 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2123 DMI_MATCH(DMI_BIOS_VERSION, "R0117A0"),
2124 DMI_MATCH(DMI_BIOS_DATE, "04/25/00"), },
2126 { /* Handle problems with APM on Sony Vaio PCG-Z600NE */
2127 swab_apm_power_in_minutes, "Sony VAIO",
2128 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2129 DMI_MATCH(DMI_BIOS_VERSION, "R0121Z1"),
2130 DMI_MATCH(DMI_BIOS_DATE, "05/11/00"), },
2132 { /* Handle problems with APM on Sony Vaio PCG-Z600NE */
2133 swab_apm_power_in_minutes, "Sony VAIO",
2134 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2135 DMI_MATCH(DMI_BIOS_VERSION, "WME01Z1"),
2136 DMI_MATCH(DMI_BIOS_DATE, "08/11/00"), },
2138 { /* Handle problems with APM on Sony Vaio PCG-Z600LEK(DE) */
2139 swab_apm_power_in_minutes, "Sony VAIO",
2140 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2141 DMI_MATCH(DMI_BIOS_VERSION, "R0206Z3"),
2142 DMI_MATCH(DMI_BIOS_DATE, "12/25/00"), },
2144 { /* Handle problems with APM on Sony Vaio PCG-Z505LS */
2145 swab_apm_power_in_minutes, "Sony VAIO",
2146 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2147 DMI_MATCH(DMI_BIOS_VERSION, "R0203D0"),
2148 DMI_MATCH(DMI_BIOS_DATE, "05/12/00"), },
2150 { /* Handle problems with APM on Sony Vaio PCG-Z505LS */
2151 swab_apm_power_in_minutes, "Sony VAIO",
2152 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2153 DMI_MATCH(DMI_BIOS_VERSION, "R0203Z3"),
2154 DMI_MATCH(DMI_BIOS_DATE, "08/25/00"), },
2156 { /* Handle problems with APM on Sony Vaio PCG-Z505LS (with updated BIOS) */
2157 swab_apm_power_in_minutes, "Sony VAIO",
2158 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2159 DMI_MATCH(DMI_BIOS_VERSION, "R0209Z3"),
2160 DMI_MATCH(DMI_BIOS_DATE, "05/12/01"), },
2162 { /* Handle problems with APM on Sony Vaio PCG-F104K */
2163 swab_apm_power_in_minutes, "Sony VAIO",
2164 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2165 DMI_MATCH(DMI_BIOS_VERSION, "R0204K2"),
2166 DMI_MATCH(DMI_BIOS_DATE, "08/28/00"), },
2169 { /* Handle problems with APM on Sony Vaio PCG-C1VN/C1VE */
2170 swab_apm_power_in_minutes, "Sony VAIO",
2171 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2172 DMI_MATCH(DMI_BIOS_VERSION, "R0208P1"),
2173 DMI_MATCH(DMI_BIOS_DATE, "11/09/00"), },
2175 { /* Handle problems with APM on Sony Vaio PCG-C1VE */
2176 swab_apm_power_in_minutes, "Sony VAIO",
2177 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2178 DMI_MATCH(DMI_BIOS_VERSION, "R0204P1"),
2179 DMI_MATCH(DMI_BIOS_DATE, "09/12/00"), },
2181 { /* Handle problems with APM on Sony Vaio PCG-C1VE */
2182 swab_apm_power_in_minutes, "Sony VAIO",
2183 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2184 DMI_MATCH(DMI_BIOS_VERSION, "WXPO1Z3"),
2185 DMI_MATCH(DMI_BIOS_DATE, "10/26/01"), },
2187 { /* broken PM poweroff bios */
2188 set_realmode_power_off, "Award Software v4.60 PGMA",
2189 { DMI_MATCH(DMI_BIOS_VENDOR, "Award Software International, Inc."),
2190 DMI_MATCH(DMI_BIOS_VERSION, "4.60 PGMA"),
2191 DMI_MATCH(DMI_BIOS_DATE, "134526184"), },
2194 /* Generic per vendor APM settings */
2196 { /* Allow interrupts during suspend on IBM laptops */
2197 set_apm_ints, "IBM",
2198 { DMI_MATCH(DMI_SYS_VENDOR, "IBM"), },
2205 * Just start the APM thread. We do NOT want to do APM BIOS
2206 * calls from anything but the APM thread, if for no other reason
2207 * than the fact that we don't trust the APM BIOS. This way,
2208 * most common APM BIOS problems that lead to protection errors
2209 * etc will have at least some level of being contained...
2211 * In short, if something bad happens, at least we have a choice
2212 * of just killing the apm thread..
2214 static int __init apm_init(void)
2216 struct proc_dir_entry *apm_proc;
2220 dmi_check_system(apm_dmi_table);
2222 if (apm_info.bios.version == 0) {
2223 printk(KERN_INFO "apm: BIOS not found.\n");
2227 "apm: BIOS version %d.%d Flags 0x%02x (Driver version %s)\n",
2228 ((apm_info.bios.version >> 8) & 0xff),
2229 (apm_info.bios.version & 0xff),
2230 apm_info.bios.flags,
2232 if ((apm_info.bios.flags & APM_32_BIT_SUPPORT) == 0) {
2233 printk(KERN_INFO "apm: no 32 bit BIOS support\n");
2238 apm_info.allow_ints = 1;
2240 apm_info.get_power_status_broken = 1;
2241 if (realmode_power_off)
2242 apm_info.realmode_power_off = 1;
2243 /* User can override, but default is to trust DMI */
2244 if (apm_disabled != -1)
2245 apm_info.disabled = apm_disabled;
2248 * Fix for the Compaq Contura 3/25c which reports BIOS version 0.1
2249 * but is reportedly a 1.0 BIOS.
2251 if (apm_info.bios.version == 0x001)
2252 apm_info.bios.version = 0x100;
2254 /* BIOS < 1.2 doesn't set cseg_16_len */
2255 if (apm_info.bios.version < 0x102)
2256 apm_info.bios.cseg_16_len = 0; /* 64k */
2259 printk(KERN_INFO "apm: entry %x:%lx cseg16 %x dseg %x",
2260 apm_info.bios.cseg, apm_info.bios.offset,
2261 apm_info.bios.cseg_16, apm_info.bios.dseg);
2262 if (apm_info.bios.version > 0x100)
2263 printk(" cseg len %x, dseg len %x",
2264 apm_info.bios.cseg_len,
2265 apm_info.bios.dseg_len);
2266 if (apm_info.bios.version > 0x101)
2267 printk(" cseg16 len %x", apm_info.bios.cseg_16_len);
2271 if (apm_info.disabled) {
2272 printk(KERN_NOTICE "apm: disabled on user request.\n");
2275 if ((num_online_cpus() > 1) && !power_off && !smp) {
2276 printk(KERN_NOTICE "apm: disabled - APM is not SMP safe.\n");
2277 apm_info.disabled = 1;
2280 if (PM_IS_ACTIVE()) {
2281 printk(KERN_NOTICE "apm: overridden by ACPI.\n");
2282 apm_info.disabled = 1;
2288 * Set up a segment that references the real mode segment 0x40
2289 * that extends up to the end of page zero (that we have reserved).
2290 * This is for buggy BIOS's that refer to (real mode) segment 0x40
2291 * even though they are called in protected mode.
2293 set_base(bad_bios_desc, __va((unsigned long)0x40 << 4));
2294 _set_limit((char *)&bad_bios_desc, 4095 - (0x40 << 4));
2296 apm_bios_entry.offset = apm_info.bios.offset;
2297 apm_bios_entry.segment = APM_CS;
2299 for (i = 0; i < NR_CPUS; i++) {
2300 struct desc_struct *gdt = get_cpu_gdt_table(i);
2301 set_base(gdt[APM_CS >> 3],
2302 __va((unsigned long)apm_info.bios.cseg << 4));
2303 set_base(gdt[APM_CS_16 >> 3],
2304 __va((unsigned long)apm_info.bios.cseg_16 << 4));
2305 set_base(gdt[APM_DS >> 3],
2306 __va((unsigned long)apm_info.bios.dseg << 4));
2307 #ifndef APM_RELAX_SEGMENTS
2308 if (apm_info.bios.version == 0x100) {
2310 /* For ASUS motherboard, Award BIOS rev 110 (and others?) */
2311 _set_limit((char *)&gdt[APM_CS >> 3], 64 * 1024 - 1);
2312 /* For some unknown machine. */
2313 _set_limit((char *)&gdt[APM_CS_16 >> 3], 64 * 1024 - 1);
2314 /* For the DEC Hinote Ultra CT475 (and others?) */
2315 _set_limit((char *)&gdt[APM_DS >> 3], 64 * 1024 - 1);
2316 #ifndef APM_RELAX_SEGMENTS
2318 _set_limit((char *)&gdt[APM_CS >> 3],
2319 (apm_info.bios.cseg_len - 1) & 0xffff);
2320 _set_limit((char *)&gdt[APM_CS_16 >> 3],
2321 (apm_info.bios.cseg_16_len - 1) & 0xffff);
2322 _set_limit((char *)&gdt[APM_DS >> 3],
2323 (apm_info.bios.dseg_len - 1) & 0xffff);
2324 /* workaround for broken BIOSes */
2325 if (apm_info.bios.cseg_len <= apm_info.bios.offset)
2326 _set_limit((char *)&gdt[APM_CS >> 3], 64 * 1024 -1);
2327 if (apm_info.bios.dseg_len <= 0x40) { /* 0x40 * 4kB == 64kB */
2328 /* for the BIOS that assumes granularity = 1 */
2329 gdt[APM_DS >> 3].b |= 0x800000;
2330 printk(KERN_NOTICE "apm: we set the granularity of dseg.\n");
2336 apm_proc = create_proc_info_entry("apm", 0, NULL, apm_get_info);
2338 apm_proc->owner = THIS_MODULE;
2340 ret = kernel_thread(apm, NULL, CLONE_KERNEL | SIGCHLD);
2342 printk(KERN_ERR "apm: disabled - Unable to start kernel thread.\n");
2346 if (num_online_cpus() > 1 && !smp ) {
2348 "apm: disabled - APM is not SMP safe (power off active).\n");
2352 misc_register(&apm_device);
2355 idle_period = (idle_period * HZ) / 100;
2356 if (idle_threshold < 100) {
2357 original_pm_idle = pm_idle;
2358 pm_idle = apm_cpu_idle;
2365 static void __exit apm_exit(void)
2370 pm_idle = original_pm_idle;
2372 * We are about to unload the current idle thread pm callback
2373 * (pm_idle), Wait for all processors to update cached/local
2374 * copies of pm_idle before proceeding.
2378 if (((apm_info.bios.flags & APM_BIOS_DISENGAGED) == 0)
2379 && (apm_info.connection_version > 0x0100)) {
2380 error = apm_engage_power_management(APM_DEVICE_ALL, 0);
2382 apm_error("disengage power management", error);
2384 misc_deregister(&apm_device);
2385 remove_proc_entry("apm", NULL);
2387 pm_power_off = NULL;
2389 while (kapmd_running)
2394 module_init(apm_init);
2395 module_exit(apm_exit);
2397 MODULE_AUTHOR("Stephen Rothwell");
2398 MODULE_DESCRIPTION("Advanced Power Management");
2399 MODULE_LICENSE("GPL");
2400 module_param(debug, bool, 0644);
2401 MODULE_PARM_DESC(debug, "Enable debug mode");
2402 module_param(power_off, bool, 0444);
2403 MODULE_PARM_DESC(power_off, "Enable power off");
2404 module_param(bounce_interval, int, 0444);
2405 MODULE_PARM_DESC(bounce_interval,
2406 "Set the number of ticks to ignore suspend bounces");
2407 module_param(allow_ints, bool, 0444);
2408 MODULE_PARM_DESC(allow_ints, "Allow interrupts during BIOS calls");
2409 module_param(broken_psr, bool, 0444);
2410 MODULE_PARM_DESC(broken_psr, "BIOS has a broken GetPowerStatus call");
2411 module_param(realmode_power_off, bool, 0444);
2412 MODULE_PARM_DESC(realmode_power_off,
2413 "Switch to real mode before powering off");
2414 module_param(idle_threshold, int, 0444);
2415 MODULE_PARM_DESC(idle_threshold,
2416 "System idle percentage above which to make APM BIOS idle calls");
2417 module_param(idle_period, int, 0444);
2418 MODULE_PARM_DESC(idle_period,
2419 "Period (in sec/100) over which to caculate the idle percentage");
2420 module_param(smp, bool, 0444);
2421 MODULE_PARM_DESC(smp,
2422 "Set this to enable APM use on an SMP platform. Use with caution on older systems");
2423 MODULE_ALIAS_MISCDEV(APM_MINOR_DEV);