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 replacement 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/whdc/archive/amp_12.mspx]
204 #include <linux/module.h>
206 #include <linux/poll.h>
207 #include <linux/types.h>
208 #include <linux/stddef.h>
209 #include <linux/timer.h>
210 #include <linux/fcntl.h>
211 #include <linux/slab.h>
212 #include <linux/stat.h>
213 #include <linux/proc_fs.h>
214 #include <linux/seq_file.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/pm_legacy.h>
222 #include <linux/capability.h>
223 #include <linux/device.h>
224 #include <linux/kernel.h>
225 #include <linux/freezer.h>
226 #include <linux/smp.h>
227 #include <linux/dmi.h>
228 #include <linux/suspend.h>
229 #include <linux/kthread.h>
230 #include <linux/jiffies.h>
232 #include <asm/system.h>
233 #include <asm/uaccess.h>
234 #include <asm/desc.h>
235 #include <asm/i8253.h>
236 #include <asm/paravirt.h>
237 #include <asm/reboot.h>
239 #if defined(CONFIG_APM_DISPLAY_BLANK) && defined(CONFIG_VT)
240 extern int (*console_blank_hook)(int);
244 * The apm_bios device is one of the misc char devices.
245 * This is its minor number.
247 #define APM_MINOR_DEV 134
250 * See Documentation/Config.help for the configuration options.
252 * Various options can be changed at boot time as follows:
253 * (We allow underscores for compatibility with the modules code)
254 * apm=on/off enable/disable APM
255 * [no-]allow[-_]ints allow interrupts during BIOS calls
256 * [no-]broken[-_]psr BIOS has a broken GetPowerStatus call
257 * [no-]realmode[-_]power[-_]off switch to real mode before
259 * [no-]debug log some debugging messages
260 * [no-]power[-_]off power off on shutdown
261 * [no-]smp Use apm even on an SMP box
262 * bounce[-_]interval=<n> number of ticks to ignore suspend
264 * idle[-_]threshold=<n> System idle percentage above which to
265 * make APM BIOS idle calls. Set it to
267 * idle[-_]period=<n> Period (in 1/100s of a second) over
268 * which the idle percentage is
272 /* KNOWN PROBLEM MACHINES:
274 * U: TI 4000M TravelMate: BIOS is *NOT* APM compliant
275 * [Confirmed by TI representative]
276 * ?: ACER 486DX4/75: uses dseg 0040, in violation of APM specification
277 * [Confirmed by BIOS disassembly]
278 * [This may work now ...]
279 * P: Toshiba 1950S: battery life information only gets updated after resume
280 * P: Midwest Micro Soundbook Elite DX2/66 monochrome: screen blanking
281 * broken in BIOS [Reported by Garst R. Reese <reese@isn.net>]
282 * ?: AcerNote-950: oops on reading /proc/apm - workaround is a WIP
283 * Neale Banks <neale@lowendale.com.au> December 2000
285 * Legend: U = unusable with APM patches
286 * P = partially usable with APM patches
290 * Define as 1 to make the driver always call the APM BIOS busy
291 * routine even if the clock was not reported as slowed by the
292 * idle routine. Otherwise, define as 0.
294 #define ALWAYS_CALL_BUSY 1
297 * Define to make the APM BIOS calls zero all data segment registers (so
298 * that an incorrect BIOS implementation will cause a kernel panic if it
299 * tries to write to arbitrary memory).
301 #define APM_ZERO_SEGS
306 * Define to re-initialize the interrupt 0 timer to 100 Hz after a suspend.
307 * This patched by Chad Miller <cmiller@surfsouth.com>, original code by
308 * David Chen <chen@ctpa04.mit.edu>
310 #undef INIT_TIMER_AFTER_SUSPEND
312 #ifdef INIT_TIMER_AFTER_SUSPEND
313 #include <linux/timex.h>
315 #include <linux/delay.h>
319 * Need to poll the APM BIOS every second
321 #define APM_CHECK_TIMEOUT (HZ)
324 * Ignore suspend events for this amount of time after a resume
326 #define DEFAULT_BOUNCE_INTERVAL (3 * HZ)
329 * Maximum number of events stored
331 #define APM_MAX_EVENTS 20
334 * The per-file APM data
338 struct apm_user *next;
339 unsigned int suser: 1;
340 unsigned int writer: 1;
341 unsigned int reader: 1;
342 unsigned int suspend_wait: 1;
344 int suspends_pending;
345 int standbys_pending;
350 apm_event_t events[APM_MAX_EVENTS];
354 * The magic number in apm_user
356 #define APM_BIOS_MAGIC 0x4101
359 * idle percentage above which bios idle calls are done
361 #ifdef CONFIG_APM_CPU_IDLE
362 #define DEFAULT_IDLE_THRESHOLD 95
364 #define DEFAULT_IDLE_THRESHOLD 100
366 #define DEFAULT_IDLE_PERIOD (100 / 3)
372 unsigned long offset;
373 unsigned short segment;
375 static int clock_slowed;
376 static int idle_threshold __read_mostly = DEFAULT_IDLE_THRESHOLD;
377 static int idle_period __read_mostly = DEFAULT_IDLE_PERIOD;
378 static int set_pm_idle;
379 static int suspends_pending;
380 static int standbys_pending;
381 static int ignore_sys_suspend;
382 static int ignore_normal_resume;
383 static int bounce_interval __read_mostly = DEFAULT_BOUNCE_INTERVAL;
385 static int debug __read_mostly;
386 static int smp __read_mostly;
387 static int apm_disabled = -1;
389 static int power_off;
391 static int power_off = 1;
393 #ifdef CONFIG_APM_REAL_MODE_POWER_OFF
394 static int realmode_power_off = 1;
396 static int realmode_power_off;
398 #ifdef CONFIG_APM_ALLOW_INTS
399 static int allow_ints = 1;
401 static int allow_ints;
403 static int broken_psr;
405 static DECLARE_WAIT_QUEUE_HEAD(apm_waitqueue);
406 static DECLARE_WAIT_QUEUE_HEAD(apm_suspend_waitqueue);
407 static struct apm_user *user_list;
408 static DEFINE_SPINLOCK(user_list_lock);
409 static const struct desc_struct bad_bios_desc = { { { 0, 0x00409200 } } };
411 static const char driver_version[] = "1.16ac"; /* no spaces */
413 static struct task_struct *kapmd_task;
416 * APM event names taken from the APM 1.2 specification. These are
417 * the message codes that the BIOS uses to tell us about events
419 static const char * const apm_event_name[] = {
425 "power status change",
430 "system standby resume",
431 "capabilities change"
433 #define NR_APM_EVENT_NAME ARRAY_SIZE(apm_event_name)
435 typedef struct lookup_t {
441 * The BIOS returns a set of standard error codes in AX when the
445 static const lookup_t error_table[] = {
446 /* N/A { APM_SUCCESS, "Operation succeeded" }, */
447 { APM_DISABLED, "Power management disabled" },
448 { APM_CONNECTED, "Real mode interface already connected" },
449 { APM_NOT_CONNECTED, "Interface not connected" },
450 { APM_16_CONNECTED, "16 bit interface already connected" },
451 /* N/A { APM_16_UNSUPPORTED, "16 bit interface not supported" }, */
452 { APM_32_CONNECTED, "32 bit interface already connected" },
453 { APM_32_UNSUPPORTED, "32 bit interface not supported" },
454 { APM_BAD_DEVICE, "Unrecognized device ID" },
455 { APM_BAD_PARAM, "Parameter out of range" },
456 { APM_NOT_ENGAGED, "Interface not engaged" },
457 { APM_BAD_FUNCTION, "Function not supported" },
458 { APM_RESUME_DISABLED, "Resume timer disabled" },
459 { APM_BAD_STATE, "Unable to enter requested state" },
460 /* N/A { APM_NO_EVENTS, "No events pending" }, */
461 { APM_NO_ERROR, "BIOS did not set a return code" },
462 { APM_NOT_PRESENT, "No APM present" }
464 #define ERROR_COUNT ARRAY_SIZE(error_table)
467 * apm_error - display an APM error
468 * @str: information string
469 * @err: APM BIOS return code
471 * Write a meaningful log entry to the kernel log in the event of
475 static void apm_error(char *str, int err)
479 for (i = 0; i < ERROR_COUNT; i++)
480 if (error_table[i].key == err)
483 printk(KERN_NOTICE "apm: %s: %s\n", str, error_table[i].msg);
485 printk(KERN_NOTICE "apm: %s: unknown error code %#2.2x\n",
490 * Lock APM functionality to physical CPU 0
495 static cpumask_t apm_save_cpus(void)
497 cpumask_t x = current->cpus_allowed;
498 /* Some bioses don't like being called from CPU != 0 */
499 set_cpus_allowed(current, cpumask_of_cpu(0));
500 BUG_ON(smp_processor_id() != 0);
504 static inline void apm_restore_cpus(cpumask_t mask)
506 set_cpus_allowed(current, mask);
512 * No CPU lockdown needed on a uniprocessor
515 #define apm_save_cpus() (current->cpus_allowed)
516 #define apm_restore_cpus(x) (void)(x)
521 * These are the actual BIOS calls. Depending on APM_ZERO_SEGS and
522 * apm_info.allow_ints, we are being really paranoid here! Not only
523 * are interrupts disabled, but all the segment registers (except SS)
524 * are saved and zeroed this means that if the BIOS tries to reference
525 * any data without explicitly loading the segment registers, the kernel
526 * will fault immediately rather than have some unforeseen circumstances
527 * for the rest of the kernel. And it will be very obvious! :-) Doing
528 * this depends on CS referring to the same physical memory as DS so that
529 * DS can be zeroed before the call. Unfortunately, we can't do anything
530 * about the stack segment/pointer. Also, we tell the compiler that
531 * everything could change.
533 * Also, we KNOW that for the non error case of apm_bios_call, there
534 * is no useful data returned in the low order 8 bits of eax.
537 static inline unsigned long __apm_irq_save(void)
540 local_save_flags(flags);
541 if (apm_info.allow_ints) {
542 if (irqs_disabled_flags(flags))
550 #define apm_irq_save(flags) \
551 do { flags = __apm_irq_save(); } while (0)
553 static inline void apm_irq_restore(unsigned long flags)
555 if (irqs_disabled_flags(flags))
557 else if (irqs_disabled())
562 # define APM_DECL_SEGS \
563 unsigned int saved_fs; unsigned int saved_gs;
564 # define APM_DO_SAVE_SEGS \
565 savesegment(fs, saved_fs); savesegment(gs, saved_gs)
566 # define APM_DO_RESTORE_SEGS \
567 loadsegment(fs, saved_fs); loadsegment(gs, saved_gs)
569 # define APM_DECL_SEGS
570 # define APM_DO_SAVE_SEGS
571 # define APM_DO_RESTORE_SEGS
575 * apm_bios_call - Make an APM BIOS 32bit call
576 * @func: APM function to execute
577 * @ebx_in: EBX register for call entry
578 * @ecx_in: ECX register for call entry
579 * @eax: EAX register return
580 * @ebx: EBX register return
581 * @ecx: ECX register return
582 * @edx: EDX register return
583 * @esi: ESI register return
585 * Make an APM call using the 32bit protected mode interface. The
586 * caller is responsible for knowing if APM BIOS is configured and
587 * enabled. This call can disable interrupts for a long period of
588 * time on some laptops. The return value is in AH and the carry
589 * flag is loaded into AL. If there is an error, then the error
590 * code is returned in AH (bits 8-15 of eax) and this function
594 static u8 apm_bios_call(u32 func, u32 ebx_in, u32 ecx_in,
595 u32 *eax, u32 *ebx, u32 *ecx, u32 *edx, u32 *esi)
601 struct desc_struct save_desc_40;
602 struct desc_struct *gdt;
604 cpus = apm_save_cpus();
607 gdt = get_cpu_gdt_table(cpu);
608 save_desc_40 = gdt[0x40 / 8];
609 gdt[0x40 / 8] = bad_bios_desc;
613 apm_bios_call_asm(func, ebx_in, ecx_in, eax, ebx, ecx, edx, esi);
615 apm_irq_restore(flags);
616 gdt[0x40 / 8] = save_desc_40;
618 apm_restore_cpus(cpus);
624 * apm_bios_call_simple - make a simple APM BIOS 32bit call
625 * @func: APM function to invoke
626 * @ebx_in: EBX register value for BIOS call
627 * @ecx_in: ECX register value for BIOS call
628 * @eax: EAX register on return from the BIOS call
630 * Make a BIOS call that returns one value only, or just status.
631 * If there is an error, then the error code is returned in AH
632 * (bits 8-15 of eax) and this function returns non-zero. This is
633 * used for simpler BIOS operations. This call may hold interrupts
634 * off for a long time on some laptops.
637 static u8 apm_bios_call_simple(u32 func, u32 ebx_in, u32 ecx_in, u32 *eax)
644 struct desc_struct save_desc_40;
645 struct desc_struct *gdt;
647 cpus = apm_save_cpus();
650 gdt = get_cpu_gdt_table(cpu);
651 save_desc_40 = gdt[0x40 / 8];
652 gdt[0x40 / 8] = bad_bios_desc;
656 error = apm_bios_call_simple_asm(func, ebx_in, ecx_in, eax);
658 apm_irq_restore(flags);
659 gdt[0x40 / 8] = save_desc_40;
661 apm_restore_cpus(cpus);
666 * apm_driver_version - APM driver version
667 * @val: loaded with the APM version on return
669 * Retrieve the APM version supported by the BIOS. This is only
670 * supported for APM 1.1 or higher. An error indicates APM 1.0 is
673 * On entry val should point to a value indicating the APM driver
674 * version with the high byte being the major and the low byte the
675 * minor number both in BCD
677 * On return it will hold the BIOS revision supported in the
681 static int apm_driver_version(u_short *val)
685 if (apm_bios_call_simple(APM_FUNC_VERSION, 0, *val, &eax))
686 return (eax >> 8) & 0xff;
692 * apm_get_event - get an APM event from the BIOS
693 * @event: pointer to the event
694 * @info: point to the event information
696 * The APM BIOS provides a polled information for event
697 * reporting. The BIOS expects to be polled at least every second
698 * when events are pending. When a message is found the caller should
699 * poll until no more messages are present. However, this causes
700 * problems on some laptops where a suspend event notification is
701 * not cleared until it is acknowledged.
703 * Additional information is returned in the info pointer, providing
704 * that APM 1.2 is in use. If no messges are pending the value 0x80
705 * is returned (No power management events pending).
708 static int apm_get_event(apm_event_t *event, apm_eventinfo_t *info)
715 if (apm_bios_call(APM_FUNC_GET_EVENT, 0, 0, &eax, &ebx, &ecx,
717 return (eax >> 8) & 0xff;
719 if (apm_info.connection_version < 0x0102)
720 *info = ~0; /* indicate info not valid */
727 * set_power_state - set the power management state
728 * @what: which items to transition
729 * @state: state to transition to
731 * Request an APM change of state for one or more system devices. The
732 * processor state must be transitioned last of all. what holds the
733 * class of device in the upper byte and the device number (0xFF for
734 * all) for the object to be transitioned.
736 * The state holds the state to transition to, which may in fact
737 * be an acceptance of a BIOS requested state change.
740 static int set_power_state(u_short what, u_short state)
744 if (apm_bios_call_simple(APM_FUNC_SET_STATE, what, state, &eax))
745 return (eax >> 8) & 0xff;
750 * set_system_power_state - set system wide power state
751 * @state: which state to enter
753 * Transition the entire system into a new APM power state.
756 static int set_system_power_state(u_short state)
758 return set_power_state(APM_DEVICE_ALL, state);
762 * apm_do_idle - perform power saving
764 * This function notifies the BIOS that the processor is (in the view
765 * of the OS) idle. It returns -1 in the event that the BIOS refuses
766 * to handle the idle request. On a success the function returns 1
767 * if the BIOS did clock slowing or 0 otherwise.
770 static int apm_do_idle(void)
777 polling = !!(current_thread_info()->status & TS_POLLING);
779 current_thread_info()->status &= ~TS_POLLING;
781 * TS_POLLING-cleared state must be visible before we
786 if (!need_resched()) {
788 ret = apm_bios_call_simple(APM_FUNC_IDLE, 0, 0, &eax);
791 current_thread_info()->status |= TS_POLLING;
797 static unsigned long t;
799 /* This always fails on some SMP boards running UP kernels.
800 * Only report the failure the first 5 times.
803 printk(KERN_DEBUG "apm_do_idle failed (%d)\n",
809 clock_slowed = (apm_info.bios.flags & APM_IDLE_SLOWS_CLOCK) != 0;
814 * apm_do_busy - inform the BIOS the CPU is busy
816 * Request that the BIOS brings the CPU back to full performance.
819 static void apm_do_busy(void)
823 if (clock_slowed || ALWAYS_CALL_BUSY) {
824 (void)apm_bios_call_simple(APM_FUNC_BUSY, 0, 0, &dummy);
830 * If no process has really been interested in
831 * the CPU for some time, we want to call BIOS
832 * power management - we probably want
835 #define IDLE_CALC_LIMIT (HZ * 100)
836 #define IDLE_LEAKY_MAX 16
838 static void (*original_pm_idle)(void) __read_mostly;
841 * apm_cpu_idle - cpu idling for APM capable Linux
843 * This is the idling function the kernel executes when APM is available. It
844 * tries to do BIOS powermanagement based on the average system idle time.
845 * Furthermore it calls the system default idle routine.
848 static void apm_cpu_idle(void)
850 static int use_apm_idle; /* = 0 */
851 static unsigned int last_jiffies; /* = 0 */
852 static unsigned int last_stime; /* = 0 */
854 int apm_idle_done = 0;
855 unsigned int jiffies_since_last_check = jiffies - last_jiffies;
859 if (jiffies_since_last_check > IDLE_CALC_LIMIT) {
861 last_jiffies = jiffies;
862 last_stime = current->stime;
863 } else if (jiffies_since_last_check > idle_period) {
864 unsigned int idle_percentage;
866 idle_percentage = current->stime - last_stime;
867 idle_percentage *= 100;
868 idle_percentage /= jiffies_since_last_check;
869 use_apm_idle = (idle_percentage > idle_threshold);
870 if (apm_info.forbid_idle)
872 last_jiffies = jiffies;
873 last_stime = current->stime;
876 bucket = IDLE_LEAKY_MAX;
878 while (!need_resched()) {
883 switch (apm_do_idle()) {
888 bucket = IDLE_LEAKY_MAX;
899 default: /* BIOS refused */
903 if (original_pm_idle)
907 jiffies_since_last_check = jiffies - last_jiffies;
908 if (jiffies_since_last_check > idle_period)
917 * apm_power_off - ask the BIOS to power off
919 * Handle the power off sequence. This is the one piece of code we
920 * will execute even on SMP machines. In order to deal with BIOS
921 * bugs we support real mode APM BIOS power off calls. We also make
922 * the SMP call on CPU0 as some systems will only honour this call
923 * on their first cpu.
926 static void apm_power_off(void)
928 unsigned char po_bios_call[] = {
929 0xb8, 0x00, 0x10, /* movw $0x1000,ax */
930 0x8e, 0xd0, /* movw ax,ss */
931 0xbc, 0x00, 0xf0, /* movw $0xf000,sp */
932 0xb8, 0x07, 0x53, /* movw $0x5307,ax */
933 0xbb, 0x01, 0x00, /* movw $0x0001,bx */
934 0xb9, 0x03, 0x00, /* movw $0x0003,cx */
935 0xcd, 0x15 /* int $0x15 */
938 /* Some bioses don't like being called from CPU != 0 */
939 if (apm_info.realmode_power_off) {
940 (void)apm_save_cpus();
941 machine_real_restart(po_bios_call, sizeof(po_bios_call));
943 (void)set_system_power_state(APM_STATE_OFF);
947 #ifdef CONFIG_APM_DO_ENABLE
950 * apm_enable_power_management - enable BIOS APM power management
951 * @enable: enable yes/no
953 * Enable or disable the APM BIOS power services.
956 static int apm_enable_power_management(int enable)
960 if ((enable == 0) && (apm_info.bios.flags & APM_BIOS_DISENGAGED))
961 return APM_NOT_ENGAGED;
962 if (apm_bios_call_simple(APM_FUNC_ENABLE_PM, APM_DEVICE_BALL,
964 return (eax >> 8) & 0xff;
966 apm_info.bios.flags &= ~APM_BIOS_DISABLED;
968 apm_info.bios.flags |= APM_BIOS_DISABLED;
974 * apm_get_power_status - get current power state
975 * @status: returned status
977 * @life: estimated life
979 * Obtain the current power status from the APM BIOS. We return a
980 * status which gives the rough battery status, and current power
981 * source. The bat value returned give an estimate as a percentage
982 * of life and a status value for the battery. The estimated life
983 * if reported is a lifetime in secodnds/minutes at current powwer
987 static int apm_get_power_status(u_short *status, u_short *bat, u_short *life)
995 if (apm_info.get_power_status_broken)
996 return APM_32_UNSUPPORTED;
997 if (apm_bios_call(APM_FUNC_GET_STATUS, APM_DEVICE_ALL, 0,
998 &eax, &ebx, &ecx, &edx, &dummy))
999 return (eax >> 8) & 0xff;
1002 if (apm_info.get_power_status_swabinminutes) {
1003 *life = swab16((u16)edx);
1011 static int apm_get_battery_status(u_short which, u_short *status,
1012 u_short *bat, u_short *life, u_short *nbat)
1020 if (apm_info.connection_version < 0x0102) {
1021 /* pretend we only have one battery. */
1023 return APM_BAD_DEVICE;
1025 return apm_get_power_status(status, bat, life);
1028 if (apm_bios_call(APM_FUNC_GET_STATUS, (0x8000 | (which)), 0, &eax,
1029 &ebx, &ecx, &edx, &esi))
1030 return (eax >> 8) & 0xff;
1040 * apm_engage_power_management - enable PM on a device
1041 * @device: identity of device
1044 * Activate or deactive power management on either a specific device
1045 * or the entire system (%APM_DEVICE_ALL).
1048 static int apm_engage_power_management(u_short device, int enable)
1052 if ((enable == 0) && (device == APM_DEVICE_ALL)
1053 && (apm_info.bios.flags & APM_BIOS_DISABLED))
1054 return APM_DISABLED;
1055 if (apm_bios_call_simple(APM_FUNC_ENGAGE_PM, device, enable, &eax))
1056 return (eax >> 8) & 0xff;
1057 if (device == APM_DEVICE_ALL) {
1059 apm_info.bios.flags &= ~APM_BIOS_DISENGAGED;
1061 apm_info.bios.flags |= APM_BIOS_DISENGAGED;
1066 #if defined(CONFIG_APM_DISPLAY_BLANK) && defined(CONFIG_VT)
1069 * apm_console_blank - blank the display
1072 * Attempt to blank the console, firstly by blanking just video device
1073 * zero, and if that fails (some BIOSes don't support it) then it blanks
1074 * all video devices. Typically the BIOS will do laptop backlight and
1075 * monitor powerdown for us.
1078 static int apm_console_blank(int blank)
1080 int error = APM_NOT_ENGAGED; /* silence gcc */
1083 static const u_short dev[3] = { 0x100, 0x1FF, 0x101 };
1085 state = blank ? APM_STATE_STANDBY : APM_STATE_READY;
1087 for (i = 0; i < ARRAY_SIZE(dev); i++) {
1088 error = set_power_state(dev[i], state);
1090 if ((error == APM_SUCCESS) || (error == APM_NO_ERROR))
1093 if (error == APM_NOT_ENGAGED)
1097 if (error == APM_NOT_ENGAGED) {
1101 eng_error = apm_engage_power_management(APM_DEVICE_ALL, 1);
1103 apm_error("set display", error);
1104 apm_error("engage interface", eng_error);
1107 return apm_console_blank(blank);
1110 apm_error("set display", error);
1115 static int queue_empty(struct apm_user *as)
1117 return as->event_head == as->event_tail;
1120 static apm_event_t get_queued_event(struct apm_user *as)
1122 if (++as->event_tail >= APM_MAX_EVENTS)
1124 return as->events[as->event_tail];
1127 static void queue_event(apm_event_t event, struct apm_user *sender)
1129 struct apm_user *as;
1131 spin_lock(&user_list_lock);
1132 if (user_list == NULL)
1134 for (as = user_list; as != NULL; as = as->next) {
1135 if ((as == sender) || (!as->reader))
1137 if (++as->event_head >= APM_MAX_EVENTS)
1140 if (as->event_head == as->event_tail) {
1141 static int notified;
1143 if (notified++ == 0)
1144 printk(KERN_ERR "apm: an event queue overflowed\n");
1145 if (++as->event_tail >= APM_MAX_EVENTS)
1148 as->events[as->event_head] = event;
1149 if ((!as->suser) || (!as->writer))
1152 case APM_SYS_SUSPEND:
1153 case APM_USER_SUSPEND:
1154 as->suspends_pending++;
1158 case APM_SYS_STANDBY:
1159 case APM_USER_STANDBY:
1160 as->standbys_pending++;
1165 wake_up_interruptible(&apm_waitqueue);
1167 spin_unlock(&user_list_lock);
1170 static void reinit_timer(void)
1172 #ifdef INIT_TIMER_AFTER_SUSPEND
1173 unsigned long flags;
1175 spin_lock_irqsave(&i8253_lock, flags);
1176 /* set the clock to HZ */
1177 outb_pit(0x34, PIT_MODE); /* binary, mode 2, LSB/MSB, ch 0 */
1179 outb_pit(LATCH & 0xff, PIT_CH0); /* LSB */
1181 outb_pit(LATCH >> 8, PIT_CH0); /* MSB */
1183 spin_unlock_irqrestore(&i8253_lock, flags);
1187 static int suspend(int vetoable)
1190 struct apm_user *as;
1192 device_suspend(PMSG_SUSPEND);
1193 local_irq_disable();
1194 device_power_down(PMSG_SUSPEND);
1198 save_processor_state();
1199 err = set_system_power_state(APM_STATE_SUSPEND);
1200 ignore_normal_resume = 1;
1201 restore_processor_state();
1203 local_irq_disable();
1206 if (err == APM_NO_ERROR)
1208 if (err != APM_SUCCESS)
1209 apm_error("suspend", err);
1210 err = (err == APM_SUCCESS) ? 0 : -EIO;
1214 queue_event(APM_NORMAL_RESUME, NULL);
1215 spin_lock(&user_list_lock);
1216 for (as = user_list; as != NULL; as = as->next) {
1217 as->suspend_wait = 0;
1218 as->suspend_result = err;
1220 spin_unlock(&user_list_lock);
1221 wake_up_interruptible(&apm_suspend_waitqueue);
1225 static void standby(void)
1229 local_irq_disable();
1230 device_power_down(PMSG_SUSPEND);
1233 err = set_system_power_state(APM_STATE_STANDBY);
1234 if ((err != APM_SUCCESS) && (err != APM_NO_ERROR))
1235 apm_error("standby", err);
1237 local_irq_disable();
1242 static apm_event_t get_event(void)
1245 apm_event_t event = APM_NO_EVENTS; /* silence gcc */
1246 apm_eventinfo_t info;
1248 static int notified;
1250 /* we don't use the eventinfo */
1251 error = apm_get_event(&event, &info);
1252 if (error == APM_SUCCESS)
1255 if ((error != APM_NO_EVENTS) && (notified++ == 0))
1256 apm_error("get_event", error);
1261 static void check_events(void)
1264 static unsigned long last_resume;
1265 static int ignore_bounce;
1267 while ((event = get_event()) != 0) {
1269 if (event <= NR_APM_EVENT_NAME)
1270 printk(KERN_DEBUG "apm: received %s notify\n",
1271 apm_event_name[event - 1]);
1273 printk(KERN_DEBUG "apm: received unknown "
1274 "event 0x%02x\n", event);
1277 && (time_after(jiffies, last_resume + bounce_interval)))
1281 case APM_SYS_STANDBY:
1282 case APM_USER_STANDBY:
1283 queue_event(event, NULL);
1284 if (standbys_pending <= 0)
1288 case APM_USER_SUSPEND:
1289 #ifdef CONFIG_APM_IGNORE_USER_SUSPEND
1290 if (apm_info.connection_version > 0x100)
1291 set_system_power_state(APM_STATE_REJECT);
1294 case APM_SYS_SUSPEND:
1295 if (ignore_bounce) {
1296 if (apm_info.connection_version > 0x100)
1297 set_system_power_state(APM_STATE_REJECT);
1301 * If we are already processing a SUSPEND,
1302 * then further SUSPEND events from the BIOS
1303 * will be ignored. We also return here to
1304 * cope with the fact that the Thinkpads keep
1305 * sending a SUSPEND event until something else
1308 if (ignore_sys_suspend)
1310 ignore_sys_suspend = 1;
1311 queue_event(event, NULL);
1312 if (suspends_pending <= 0)
1316 case APM_NORMAL_RESUME:
1317 case APM_CRITICAL_RESUME:
1318 case APM_STANDBY_RESUME:
1319 ignore_sys_suspend = 0;
1320 last_resume = jiffies;
1322 if ((event != APM_NORMAL_RESUME)
1323 || (ignore_normal_resume == 0)) {
1325 queue_event(event, NULL);
1327 ignore_normal_resume = 0;
1330 case APM_CAPABILITY_CHANGE:
1331 case APM_LOW_BATTERY:
1332 case APM_POWER_STATUS_CHANGE:
1333 queue_event(event, NULL);
1334 /* If needed, notify drivers here */
1337 case APM_UPDATE_TIME:
1340 case APM_CRITICAL_SUSPEND:
1342 * We are not allowed to reject a critical suspend.
1350 static void apm_event_handler(void)
1352 static int pending_count = 4;
1355 if ((standbys_pending > 0) || (suspends_pending > 0)) {
1356 if ((apm_info.connection_version > 0x100) &&
1357 (pending_count-- <= 0)) {
1360 printk(KERN_DEBUG "apm: setting state busy\n");
1361 err = set_system_power_state(APM_STATE_BUSY);
1363 apm_error("busy", err);
1371 * This is the APM thread main loop.
1374 static void apm_mainloop(void)
1376 DECLARE_WAITQUEUE(wait, current);
1378 add_wait_queue(&apm_waitqueue, &wait);
1379 set_current_state(TASK_INTERRUPTIBLE);
1381 schedule_timeout(APM_CHECK_TIMEOUT);
1382 if (kthread_should_stop())
1385 * Ok, check all events, check for idle (and mark us sleeping
1386 * so as not to count towards the load average)..
1388 set_current_state(TASK_INTERRUPTIBLE);
1389 apm_event_handler();
1391 remove_wait_queue(&apm_waitqueue, &wait);
1394 static int check_apm_user(struct apm_user *as, const char *func)
1396 if ((as == NULL) || (as->magic != APM_BIOS_MAGIC)) {
1397 printk(KERN_ERR "apm: %s passed bad filp\n", func);
1403 static ssize_t do_read(struct file *fp, char __user *buf, size_t count, loff_t *ppos)
1405 struct apm_user *as;
1409 as = fp->private_data;
1410 if (check_apm_user(as, "read"))
1412 if ((int)count < sizeof(apm_event_t))
1414 if ((queue_empty(as)) && (fp->f_flags & O_NONBLOCK))
1416 wait_event_interruptible(apm_waitqueue, !queue_empty(as));
1418 while ((i >= sizeof(event)) && !queue_empty(as)) {
1419 event = get_queued_event(as);
1420 if (copy_to_user(buf, &event, sizeof(event))) {
1426 case APM_SYS_SUSPEND:
1427 case APM_USER_SUSPEND:
1428 as->suspends_read++;
1431 case APM_SYS_STANDBY:
1432 case APM_USER_STANDBY:
1433 as->standbys_read++;
1436 buf += sizeof(event);
1441 if (signal_pending(current))
1442 return -ERESTARTSYS;
1446 static unsigned int do_poll(struct file *fp, poll_table *wait)
1448 struct apm_user *as;
1450 as = fp->private_data;
1451 if (check_apm_user(as, "poll"))
1453 poll_wait(fp, &apm_waitqueue, wait);
1454 if (!queue_empty(as))
1455 return POLLIN | POLLRDNORM;
1459 static int do_ioctl(struct inode *inode, struct file *filp,
1460 u_int cmd, u_long arg)
1462 struct apm_user *as;
1464 as = filp->private_data;
1465 if (check_apm_user(as, "ioctl"))
1467 if ((!as->suser) || (!as->writer))
1470 case APM_IOC_STANDBY:
1471 if (as->standbys_read > 0) {
1472 as->standbys_read--;
1473 as->standbys_pending--;
1476 queue_event(APM_USER_STANDBY, as);
1477 if (standbys_pending <= 0)
1480 case APM_IOC_SUSPEND:
1481 if (as->suspends_read > 0) {
1482 as->suspends_read--;
1483 as->suspends_pending--;
1486 queue_event(APM_USER_SUSPEND, as);
1487 if (suspends_pending <= 0) {
1490 as->suspend_wait = 1;
1491 wait_event_interruptible(apm_suspend_waitqueue,
1492 as->suspend_wait == 0);
1493 return as->suspend_result;
1502 static int do_release(struct inode *inode, struct file *filp)
1504 struct apm_user *as;
1506 as = filp->private_data;
1507 if (check_apm_user(as, "release"))
1509 filp->private_data = NULL;
1510 if (as->standbys_pending > 0) {
1511 standbys_pending -= as->standbys_pending;
1512 if (standbys_pending <= 0)
1515 if (as->suspends_pending > 0) {
1516 suspends_pending -= as->suspends_pending;
1517 if (suspends_pending <= 0)
1520 spin_lock(&user_list_lock);
1521 if (user_list == as)
1522 user_list = as->next;
1524 struct apm_user *as1;
1526 for (as1 = user_list;
1527 (as1 != NULL) && (as1->next != as);
1531 printk(KERN_ERR "apm: filp not in user list\n");
1533 as1->next = as->next;
1535 spin_unlock(&user_list_lock);
1540 static int do_open(struct inode *inode, struct file *filp)
1542 struct apm_user *as;
1544 as = kmalloc(sizeof(*as), GFP_KERNEL);
1546 printk(KERN_ERR "apm: cannot allocate struct of size %d bytes\n",
1550 as->magic = APM_BIOS_MAGIC;
1551 as->event_tail = as->event_head = 0;
1552 as->suspends_pending = as->standbys_pending = 0;
1553 as->suspends_read = as->standbys_read = 0;
1555 * XXX - this is a tiny bit broken, when we consider BSD
1556 * process accounting. If the device is opened by root, we
1557 * instantly flag that we used superuser privs. Who knows,
1558 * we might close the device immediately without doing a
1559 * privileged operation -- cevans
1561 as->suser = capable(CAP_SYS_ADMIN);
1562 as->writer = (filp->f_mode & FMODE_WRITE) == FMODE_WRITE;
1563 as->reader = (filp->f_mode & FMODE_READ) == FMODE_READ;
1564 spin_lock(&user_list_lock);
1565 as->next = user_list;
1567 spin_unlock(&user_list_lock);
1568 filp->private_data = as;
1572 static int proc_apm_show(struct seq_file *m, void *v)
1578 unsigned short ac_line_status = 0xff;
1579 unsigned short battery_status = 0xff;
1580 unsigned short battery_flag = 0xff;
1581 int percentage = -1;
1582 int time_units = -1;
1585 if ((num_online_cpus() == 1) &&
1586 !(error = apm_get_power_status(&bx, &cx, &dx))) {
1587 ac_line_status = (bx >> 8) & 0xff;
1588 battery_status = bx & 0xff;
1589 if ((cx & 0xff) != 0xff)
1590 percentage = cx & 0xff;
1592 if (apm_info.connection_version > 0x100) {
1593 battery_flag = (cx >> 8) & 0xff;
1595 units = (dx & 0x8000) ? "min" : "sec";
1596 time_units = dx & 0x7fff;
1600 /* Arguments, with symbols from linux/apm_bios.h. Information is
1601 from the Get Power Status (0x0a) call unless otherwise noted.
1603 0) Linux driver version (this will change if format changes)
1604 1) APM BIOS Version. Usually 1.0, 1.1 or 1.2.
1605 2) APM flags from APM Installation Check (0x00):
1606 bit 0: APM_16_BIT_SUPPORT
1607 bit 1: APM_32_BIT_SUPPORT
1608 bit 2: APM_IDLE_SLOWS_CLOCK
1609 bit 3: APM_BIOS_DISABLED
1610 bit 4: APM_BIOS_DISENGAGED
1614 0x02: On backup power (BIOS >= 1.1 only)
1621 0x04: Selected battery not present (BIOS >= 1.2 only)
1628 bit 7: No system battery
1630 6) Remaining battery life (percentage of charge):
1633 7) Remaining battery life (time units):
1634 Number of remaining minutes or seconds
1636 8) min = minutes; sec = seconds */
1638 seq_printf(m, "%s %d.%d 0x%02x 0x%02x 0x%02x 0x%02x %d%% %d %s\n",
1640 (apm_info.bios.version >> 8) & 0xff,
1641 apm_info.bios.version & 0xff,
1642 apm_info.bios.flags,
1652 static int proc_apm_open(struct inode *inode, struct file *file)
1654 return single_open(file, proc_apm_show, NULL);
1657 static const struct file_operations apm_file_ops = {
1658 .owner = THIS_MODULE,
1659 .open = proc_apm_open,
1661 .llseek = seq_lseek,
1662 .release = single_release,
1665 static int apm(void *unused)
1676 * This is to avoid random crashes at boot time during initialization
1677 * on SMP systems in case of "apm=power-off" mode. Seen on ASUS A7M266D.
1678 * Some bioses don't like being called from CPU != 0.
1679 * Method suggested by Ingo Molnar.
1681 set_cpus_allowed(current, cpumask_of_cpu(0));
1682 BUG_ON(smp_processor_id() != 0);
1685 if (apm_info.connection_version == 0) {
1686 apm_info.connection_version = apm_info.bios.version;
1687 if (apm_info.connection_version > 0x100) {
1689 * We only support BIOSs up to version 1.2
1691 if (apm_info.connection_version > 0x0102)
1692 apm_info.connection_version = 0x0102;
1693 error = apm_driver_version(&apm_info.connection_version);
1694 if (error != APM_SUCCESS) {
1695 apm_error("driver version", error);
1696 /* Fall back to an APM 1.0 connection. */
1697 apm_info.connection_version = 0x100;
1703 printk(KERN_INFO "apm: Connection version %d.%d\n",
1704 (apm_info.connection_version >> 8) & 0xff,
1705 apm_info.connection_version & 0xff);
1707 #ifdef CONFIG_APM_DO_ENABLE
1708 if (apm_info.bios.flags & APM_BIOS_DISABLED) {
1710 * This call causes my NEC UltraLite Versa 33/C to hang if it
1711 * is booted with PM disabled but not in the docking station.
1714 error = apm_enable_power_management(1);
1716 apm_error("enable power management", error);
1722 if ((apm_info.bios.flags & APM_BIOS_DISENGAGED)
1723 && (apm_info.connection_version > 0x0100)) {
1724 error = apm_engage_power_management(APM_DEVICE_ALL, 1);
1726 apm_error("engage power management", error);
1731 if (debug && (num_online_cpus() == 1 || smp)) {
1732 error = apm_get_power_status(&bx, &cx, &dx);
1734 printk(KERN_INFO "apm: power status not available\n");
1736 switch ((bx >> 8) & 0xff) {
1738 power_stat = "off line";
1741 power_stat = "on line";
1744 power_stat = "on backup power";
1747 power_stat = "unknown";
1750 switch (bx & 0xff) {
1758 bat_stat = "critical";
1761 bat_stat = "charging";
1764 bat_stat = "unknown";
1768 "apm: AC %s, battery status %s, battery life ",
1769 power_stat, bat_stat);
1770 if ((cx & 0xff) == 0xff)
1771 printk("unknown\n");
1773 printk("%d%%\n", cx & 0xff);
1774 if (apm_info.connection_version > 0x100) {
1776 "apm: battery flag 0x%02x, battery life ",
1779 printk("unknown\n");
1781 printk("%d %s\n", dx & 0x7fff,
1783 "minutes" : "seconds");
1788 /* Install our power off handler.. */
1790 pm_power_off = apm_power_off;
1792 if (num_online_cpus() == 1 || smp) {
1793 #if defined(CONFIG_APM_DISPLAY_BLANK) && defined(CONFIG_VT)
1794 console_blank_hook = apm_console_blank;
1797 #if defined(CONFIG_APM_DISPLAY_BLANK) && defined(CONFIG_VT)
1798 console_blank_hook = NULL;
1806 static int __init apm_setup(char *str)
1810 while ((str != NULL) && (*str != '\0')) {
1811 if (strncmp(str, "off", 3) == 0)
1813 if (strncmp(str, "on", 2) == 0)
1815 if ((strncmp(str, "bounce-interval=", 16) == 0) ||
1816 (strncmp(str, "bounce_interval=", 16) == 0))
1817 bounce_interval = simple_strtol(str + 16, NULL, 0);
1818 if ((strncmp(str, "idle-threshold=", 15) == 0) ||
1819 (strncmp(str, "idle_threshold=", 15) == 0))
1820 idle_threshold = simple_strtol(str + 15, NULL, 0);
1821 if ((strncmp(str, "idle-period=", 12) == 0) ||
1822 (strncmp(str, "idle_period=", 12) == 0))
1823 idle_period = simple_strtol(str + 12, NULL, 0);
1824 invert = (strncmp(str, "no-", 3) == 0) ||
1825 (strncmp(str, "no_", 3) == 0);
1828 if (strncmp(str, "debug", 5) == 0)
1830 if ((strncmp(str, "power-off", 9) == 0) ||
1831 (strncmp(str, "power_off", 9) == 0))
1832 power_off = !invert;
1833 if (strncmp(str, "smp", 3) == 0) {
1835 idle_threshold = 100;
1837 if ((strncmp(str, "allow-ints", 10) == 0) ||
1838 (strncmp(str, "allow_ints", 10) == 0))
1839 apm_info.allow_ints = !invert;
1840 if ((strncmp(str, "broken-psr", 10) == 0) ||
1841 (strncmp(str, "broken_psr", 10) == 0))
1842 apm_info.get_power_status_broken = !invert;
1843 if ((strncmp(str, "realmode-power-off", 18) == 0) ||
1844 (strncmp(str, "realmode_power_off", 18) == 0))
1845 apm_info.realmode_power_off = !invert;
1846 str = strchr(str, ',');
1848 str += strspn(str, ", \t");
1853 __setup("apm=", apm_setup);
1856 static const struct file_operations apm_bios_fops = {
1857 .owner = THIS_MODULE,
1862 .release = do_release,
1865 static struct miscdevice apm_device = {
1872 /* Simple "print if true" callback */
1873 static int __init print_if_true(const struct dmi_system_id *d)
1875 printk("%s\n", d->ident);
1880 * Some Bioses enable the PS/2 mouse (touchpad) at resume, even if it was
1881 * disabled before the suspend. Linux used to get terribly confused by that.
1883 static int __init broken_ps2_resume(const struct dmi_system_id *d)
1885 printk(KERN_INFO "%s machine detected. Mousepad Resume Bug "
1886 "workaround hopefully not needed.\n", d->ident);
1890 /* Some bioses have a broken protected mode poweroff and need to use realmode */
1891 static int __init set_realmode_power_off(const struct dmi_system_id *d)
1893 if (apm_info.realmode_power_off == 0) {
1894 apm_info.realmode_power_off = 1;
1895 printk(KERN_INFO "%s bios detected. "
1896 "Using realmode poweroff only.\n", d->ident);
1901 /* Some laptops require interrupts to be enabled during APM calls */
1902 static int __init set_apm_ints(const struct dmi_system_id *d)
1904 if (apm_info.allow_ints == 0) {
1905 apm_info.allow_ints = 1;
1906 printk(KERN_INFO "%s machine detected. "
1907 "Enabling interrupts during APM calls.\n", d->ident);
1912 /* Some APM bioses corrupt memory or just plain do not work */
1913 static int __init apm_is_horked(const struct dmi_system_id *d)
1915 if (apm_info.disabled == 0) {
1916 apm_info.disabled = 1;
1917 printk(KERN_INFO "%s machine detected. "
1918 "Disabling APM.\n", d->ident);
1923 static int __init apm_is_horked_d850md(const struct dmi_system_id *d)
1925 if (apm_info.disabled == 0) {
1926 apm_info.disabled = 1;
1927 printk(KERN_INFO "%s machine detected. "
1928 "Disabling APM.\n", d->ident);
1929 printk(KERN_INFO "This bug is fixed in bios P15 which is available for \n");
1930 printk(KERN_INFO "download from support.intel.com \n");
1935 /* Some APM bioses hang on APM idle calls */
1936 static int __init apm_likes_to_melt(const struct dmi_system_id *d)
1938 if (apm_info.forbid_idle == 0) {
1939 apm_info.forbid_idle = 1;
1940 printk(KERN_INFO "%s machine detected. "
1941 "Disabling APM idle calls.\n", d->ident);
1947 * Check for clue free BIOS implementations who use
1948 * the following QA technique
1950 * [ Write BIOS Code ]<------
1952 * < Does it Compile >----N--
1954 * < Does it Boot Win98 >-N--
1958 * Phoenix A04 08/24/2000 is known bad (Dell Inspiron 5000e)
1959 * Phoenix A07 09/29/2000 is known good (Dell Inspiron 5000)
1961 static int __init broken_apm_power(const struct dmi_system_id *d)
1963 apm_info.get_power_status_broken = 1;
1964 printk(KERN_WARNING "BIOS strings suggest APM bugs, "
1965 "disabling power status reporting.\n");
1970 * This bios swaps the APM minute reporting bytes over (Many sony laptops
1971 * have this problem).
1973 static int __init swab_apm_power_in_minutes(const struct dmi_system_id *d)
1975 apm_info.get_power_status_swabinminutes = 1;
1976 printk(KERN_WARNING "BIOS strings suggest APM reports battery life "
1977 "in minutes and wrong byte order.\n");
1981 static struct dmi_system_id __initdata apm_dmi_table[] = {
1984 KERN_WARNING "IBM T23 - BIOS 1.03b+ and controller firmware 1.02+ may be needed for Linux APM.",
1985 { DMI_MATCH(DMI_SYS_VENDOR, "IBM"),
1986 DMI_MATCH(DMI_BIOS_VERSION, "1AET38WW (1.01b)"), },
1988 { /* Handle problems with APM on the C600 */
1989 broken_ps2_resume, "Dell Latitude C600",
1990 { DMI_MATCH(DMI_SYS_VENDOR, "Dell"),
1991 DMI_MATCH(DMI_PRODUCT_NAME, "Latitude C600"), },
1993 { /* Allow interrupts during suspend on Dell Latitude laptops*/
1994 set_apm_ints, "Dell Latitude",
1995 { DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
1996 DMI_MATCH(DMI_PRODUCT_NAME, "Latitude C510"), }
1999 apm_is_horked, "Dell Inspiron 2500",
2000 { DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
2001 DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 2500"),
2002 DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2003 DMI_MATCH(DMI_BIOS_VERSION, "A11"), },
2005 { /* Allow interrupts during suspend on Dell Inspiron laptops*/
2006 set_apm_ints, "Dell Inspiron", {
2007 DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
2008 DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 4000"), },
2010 { /* Handle problems with APM on Inspiron 5000e */
2011 broken_apm_power, "Dell Inspiron 5000e",
2012 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2013 DMI_MATCH(DMI_BIOS_VERSION, "A04"),
2014 DMI_MATCH(DMI_BIOS_DATE, "08/24/2000"), },
2016 { /* Handle problems with APM on Inspiron 2500 */
2017 broken_apm_power, "Dell Inspiron 2500",
2018 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2019 DMI_MATCH(DMI_BIOS_VERSION, "A12"),
2020 DMI_MATCH(DMI_BIOS_DATE, "02/04/2002"), },
2023 apm_is_horked, "Dell Dimension 4100",
2024 { DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
2025 DMI_MATCH(DMI_PRODUCT_NAME, "XPS-Z"),
2026 DMI_MATCH(DMI_BIOS_VENDOR, "Intel Corp."),
2027 DMI_MATCH(DMI_BIOS_VERSION, "A11"), },
2029 { /* Allow interrupts during suspend on Compaq Laptops*/
2030 set_apm_ints, "Compaq 12XL125",
2031 { DMI_MATCH(DMI_SYS_VENDOR, "Compaq"),
2032 DMI_MATCH(DMI_PRODUCT_NAME, "Compaq PC"),
2033 DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2034 DMI_MATCH(DMI_BIOS_VERSION, "4.06"), },
2036 { /* Allow interrupts during APM or the clock goes slow */
2037 set_apm_ints, "ASUSTeK",
2038 { DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK Computer Inc."),
2039 DMI_MATCH(DMI_PRODUCT_NAME, "L8400K series Notebook PC"), },
2041 { /* APM blows on shutdown */
2042 apm_is_horked, "ABIT KX7-333[R]",
2043 { DMI_MATCH(DMI_BOARD_VENDOR, "ABIT"),
2044 DMI_MATCH(DMI_BOARD_NAME, "VT8367-8233A (KX7-333[R])"), },
2047 apm_is_horked, "Trigem Delhi3",
2048 { DMI_MATCH(DMI_SYS_VENDOR, "TriGem Computer, Inc"),
2049 DMI_MATCH(DMI_PRODUCT_NAME, "Delhi3"), },
2052 apm_is_horked, "Fujitsu-Siemens",
2053 { DMI_MATCH(DMI_BIOS_VENDOR, "hoenix/FUJITSU SIEMENS"),
2054 DMI_MATCH(DMI_BIOS_VERSION, "Version1.01"), },
2057 apm_is_horked_d850md, "Intel D850MD",
2058 { DMI_MATCH(DMI_BIOS_VENDOR, "Intel Corp."),
2059 DMI_MATCH(DMI_BIOS_VERSION, "MV85010A.86A.0016.P07.0201251536"), },
2062 apm_is_horked, "Intel D810EMO",
2063 { DMI_MATCH(DMI_BIOS_VENDOR, "Intel Corp."),
2064 DMI_MATCH(DMI_BIOS_VERSION, "MO81010A.86A.0008.P04.0004170800"), },
2067 apm_is_horked, "Dell XPS-Z",
2068 { DMI_MATCH(DMI_BIOS_VENDOR, "Intel Corp."),
2069 DMI_MATCH(DMI_BIOS_VERSION, "A11"),
2070 DMI_MATCH(DMI_PRODUCT_NAME, "XPS-Z"), },
2073 apm_is_horked, "Sharp PC-PJ/AX",
2074 { DMI_MATCH(DMI_SYS_VENDOR, "SHARP"),
2075 DMI_MATCH(DMI_PRODUCT_NAME, "PC-PJ/AX"),
2076 DMI_MATCH(DMI_BIOS_VENDOR, "SystemSoft"),
2077 DMI_MATCH(DMI_BIOS_VERSION, "Version R2.08"), },
2080 apm_is_horked, "Dell Inspiron 2500",
2081 { DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
2082 DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 2500"),
2083 DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2084 DMI_MATCH(DMI_BIOS_VERSION, "A11"), },
2086 { /* APM idle hangs */
2087 apm_likes_to_melt, "Jabil AMD",
2088 { DMI_MATCH(DMI_BIOS_VENDOR, "American Megatrends Inc."),
2089 DMI_MATCH(DMI_BIOS_VERSION, "0AASNP06"), },
2091 { /* APM idle hangs */
2092 apm_likes_to_melt, "AMI Bios",
2093 { DMI_MATCH(DMI_BIOS_VENDOR, "American Megatrends Inc."),
2094 DMI_MATCH(DMI_BIOS_VERSION, "0AASNP05"), },
2096 { /* Handle problems with APM on Sony Vaio PCG-N505X(DE) */
2097 swab_apm_power_in_minutes, "Sony VAIO",
2098 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2099 DMI_MATCH(DMI_BIOS_VERSION, "R0206H"),
2100 DMI_MATCH(DMI_BIOS_DATE, "08/23/99"), },
2102 { /* Handle problems with APM on Sony Vaio PCG-N505VX */
2103 swab_apm_power_in_minutes, "Sony VAIO",
2104 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2105 DMI_MATCH(DMI_BIOS_VERSION, "W2K06H0"),
2106 DMI_MATCH(DMI_BIOS_DATE, "02/03/00"), },
2108 { /* Handle problems with APM on Sony Vaio PCG-XG29 */
2109 swab_apm_power_in_minutes, "Sony VAIO",
2110 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2111 DMI_MATCH(DMI_BIOS_VERSION, "R0117A0"),
2112 DMI_MATCH(DMI_BIOS_DATE, "04/25/00"), },
2114 { /* Handle problems with APM on Sony Vaio PCG-Z600NE */
2115 swab_apm_power_in_minutes, "Sony VAIO",
2116 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2117 DMI_MATCH(DMI_BIOS_VERSION, "R0121Z1"),
2118 DMI_MATCH(DMI_BIOS_DATE, "05/11/00"), },
2120 { /* Handle problems with APM on Sony Vaio PCG-Z600NE */
2121 swab_apm_power_in_minutes, "Sony VAIO",
2122 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2123 DMI_MATCH(DMI_BIOS_VERSION, "WME01Z1"),
2124 DMI_MATCH(DMI_BIOS_DATE, "08/11/00"), },
2126 { /* Handle problems with APM on Sony Vaio PCG-Z600LEK(DE) */
2127 swab_apm_power_in_minutes, "Sony VAIO",
2128 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2129 DMI_MATCH(DMI_BIOS_VERSION, "R0206Z3"),
2130 DMI_MATCH(DMI_BIOS_DATE, "12/25/00"), },
2132 { /* Handle problems with APM on Sony Vaio PCG-Z505LS */
2133 swab_apm_power_in_minutes, "Sony VAIO",
2134 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2135 DMI_MATCH(DMI_BIOS_VERSION, "R0203D0"),
2136 DMI_MATCH(DMI_BIOS_DATE, "05/12/00"), },
2138 { /* Handle problems with APM on Sony Vaio PCG-Z505LS */
2139 swab_apm_power_in_minutes, "Sony VAIO",
2140 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2141 DMI_MATCH(DMI_BIOS_VERSION, "R0203Z3"),
2142 DMI_MATCH(DMI_BIOS_DATE, "08/25/00"), },
2144 { /* Handle problems with APM on Sony Vaio PCG-Z505LS (with updated BIOS) */
2145 swab_apm_power_in_minutes, "Sony VAIO",
2146 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2147 DMI_MATCH(DMI_BIOS_VERSION, "R0209Z3"),
2148 DMI_MATCH(DMI_BIOS_DATE, "05/12/01"), },
2150 { /* Handle problems with APM on Sony Vaio PCG-F104K */
2151 swab_apm_power_in_minutes, "Sony VAIO",
2152 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2153 DMI_MATCH(DMI_BIOS_VERSION, "R0204K2"),
2154 DMI_MATCH(DMI_BIOS_DATE, "08/28/00"), },
2157 { /* Handle problems with APM on Sony Vaio PCG-C1VN/C1VE */
2158 swab_apm_power_in_minutes, "Sony VAIO",
2159 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2160 DMI_MATCH(DMI_BIOS_VERSION, "R0208P1"),
2161 DMI_MATCH(DMI_BIOS_DATE, "11/09/00"), },
2163 { /* Handle problems with APM on Sony Vaio PCG-C1VE */
2164 swab_apm_power_in_minutes, "Sony VAIO",
2165 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2166 DMI_MATCH(DMI_BIOS_VERSION, "R0204P1"),
2167 DMI_MATCH(DMI_BIOS_DATE, "09/12/00"), },
2169 { /* Handle problems with APM on Sony Vaio PCG-C1VE */
2170 swab_apm_power_in_minutes, "Sony VAIO",
2171 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2172 DMI_MATCH(DMI_BIOS_VERSION, "WXPO1Z3"),
2173 DMI_MATCH(DMI_BIOS_DATE, "10/26/01"), },
2175 { /* broken PM poweroff bios */
2176 set_realmode_power_off, "Award Software v4.60 PGMA",
2177 { DMI_MATCH(DMI_BIOS_VENDOR, "Award Software International, Inc."),
2178 DMI_MATCH(DMI_BIOS_VERSION, "4.60 PGMA"),
2179 DMI_MATCH(DMI_BIOS_DATE, "134526184"), },
2182 /* Generic per vendor APM settings */
2184 { /* Allow interrupts during suspend on IBM laptops */
2185 set_apm_ints, "IBM",
2186 { DMI_MATCH(DMI_SYS_VENDOR, "IBM"), },
2193 * Just start the APM thread. We do NOT want to do APM BIOS
2194 * calls from anything but the APM thread, if for no other reason
2195 * than the fact that we don't trust the APM BIOS. This way,
2196 * most common APM BIOS problems that lead to protection errors
2197 * etc will have at least some level of being contained...
2199 * In short, if something bad happens, at least we have a choice
2200 * of just killing the apm thread..
2202 static int __init apm_init(void)
2204 struct proc_dir_entry *apm_proc;
2205 struct desc_struct *gdt;
2208 dmi_check_system(apm_dmi_table);
2210 if (apm_info.bios.version == 0 || paravirt_enabled()) {
2211 printk(KERN_INFO "apm: BIOS not found.\n");
2215 "apm: BIOS version %d.%d Flags 0x%02x (Driver version %s)\n",
2216 ((apm_info.bios.version >> 8) & 0xff),
2217 (apm_info.bios.version & 0xff),
2218 apm_info.bios.flags,
2220 if ((apm_info.bios.flags & APM_32_BIT_SUPPORT) == 0) {
2221 printk(KERN_INFO "apm: no 32 bit BIOS support\n");
2226 apm_info.allow_ints = 1;
2228 apm_info.get_power_status_broken = 1;
2229 if (realmode_power_off)
2230 apm_info.realmode_power_off = 1;
2231 /* User can override, but default is to trust DMI */
2232 if (apm_disabled != -1)
2233 apm_info.disabled = apm_disabled;
2236 * Fix for the Compaq Contura 3/25c which reports BIOS version 0.1
2237 * but is reportedly a 1.0 BIOS.
2239 if (apm_info.bios.version == 0x001)
2240 apm_info.bios.version = 0x100;
2242 /* BIOS < 1.2 doesn't set cseg_16_len */
2243 if (apm_info.bios.version < 0x102)
2244 apm_info.bios.cseg_16_len = 0; /* 64k */
2247 printk(KERN_INFO "apm: entry %x:%x cseg16 %x dseg %x",
2248 apm_info.bios.cseg, apm_info.bios.offset,
2249 apm_info.bios.cseg_16, apm_info.bios.dseg);
2250 if (apm_info.bios.version > 0x100)
2251 printk(" cseg len %x, dseg len %x",
2252 apm_info.bios.cseg_len,
2253 apm_info.bios.dseg_len);
2254 if (apm_info.bios.version > 0x101)
2255 printk(" cseg16 len %x", apm_info.bios.cseg_16_len);
2259 if (apm_info.disabled) {
2260 printk(KERN_NOTICE "apm: disabled on user request.\n");
2263 if ((num_online_cpus() > 1) && !power_off && !smp) {
2264 printk(KERN_NOTICE "apm: disabled - APM is not SMP safe.\n");
2265 apm_info.disabled = 1;
2268 if (pm_flags & PM_ACPI) {
2269 printk(KERN_NOTICE "apm: overridden by ACPI.\n");
2270 apm_info.disabled = 1;
2276 * Set up a segment that references the real mode segment 0x40
2277 * that extends up to the end of page zero (that we have reserved).
2278 * This is for buggy BIOS's that refer to (real mode) segment 0x40
2279 * even though they are called in protected mode.
2281 set_base(bad_bios_desc, __va((unsigned long)0x40 << 4));
2282 _set_limit((char *)&bad_bios_desc, 4095 - (0x40 << 4));
2285 * Set up the long jump entry point to the APM BIOS, which is called
2286 * from inline assembly.
2288 apm_bios_entry.offset = apm_info.bios.offset;
2289 apm_bios_entry.segment = APM_CS;
2292 * The APM 1.1 BIOS is supposed to provide limit information that it
2293 * recognizes. Many machines do this correctly, but many others do
2294 * not restrict themselves to their claimed limit. When this happens,
2295 * they will cause a segmentation violation in the kernel at boot time.
2296 * Most BIOS's, however, will respect a 64k limit, so we use that.
2298 * Note we only set APM segments on CPU zero, since we pin the APM
2301 gdt = get_cpu_gdt_table(0);
2302 set_base(gdt[APM_CS >> 3],
2303 __va((unsigned long)apm_info.bios.cseg << 4));
2304 set_base(gdt[APM_CS_16 >> 3],
2305 __va((unsigned long)apm_info.bios.cseg_16 << 4));
2306 set_base(gdt[APM_DS >> 3],
2307 __va((unsigned long)apm_info.bios.dseg << 4));
2309 apm_proc = create_proc_entry("apm", 0, NULL);
2311 apm_proc->proc_fops = &apm_file_ops;
2313 kapmd_task = kthread_create(apm, NULL, "kapmd");
2314 if (IS_ERR(kapmd_task)) {
2315 printk(KERN_ERR "apm: disabled - Unable to start kernel "
2317 err = PTR_ERR(kapmd_task);
2319 remove_proc_entry("apm", NULL);
2322 wake_up_process(kapmd_task);
2324 if (num_online_cpus() > 1 && !smp) {
2326 "apm: disabled - APM is not SMP safe (power off active).\n");
2331 * Note we don't actually care if the misc_device cannot be registered.
2332 * this driver can do its job without it, even if userspace can't
2333 * control it. just log the error
2335 if (misc_register(&apm_device))
2336 printk(KERN_WARNING "apm: Could not register misc device.\n");
2339 idle_period = (idle_period * HZ) / 100;
2340 if (idle_threshold < 100) {
2341 original_pm_idle = pm_idle;
2342 pm_idle = apm_cpu_idle;
2349 static void __exit apm_exit(void)
2354 pm_idle = original_pm_idle;
2356 * We are about to unload the current idle thread pm callback
2357 * (pm_idle), Wait for all processors to update cached/local
2358 * copies of pm_idle before proceeding.
2362 if (((apm_info.bios.flags & APM_BIOS_DISENGAGED) == 0)
2363 && (apm_info.connection_version > 0x0100)) {
2364 error = apm_engage_power_management(APM_DEVICE_ALL, 0);
2366 apm_error("disengage power management", error);
2368 misc_deregister(&apm_device);
2369 remove_proc_entry("apm", NULL);
2371 pm_power_off = NULL;
2373 kthread_stop(kapmd_task);
2376 pm_flags &= ~PM_APM;
2379 module_init(apm_init);
2380 module_exit(apm_exit);
2382 MODULE_AUTHOR("Stephen Rothwell");
2383 MODULE_DESCRIPTION("Advanced Power Management");
2384 MODULE_LICENSE("GPL");
2385 module_param(debug, bool, 0644);
2386 MODULE_PARM_DESC(debug, "Enable debug mode");
2387 module_param(power_off, bool, 0444);
2388 MODULE_PARM_DESC(power_off, "Enable power off");
2389 module_param(bounce_interval, int, 0444);
2390 MODULE_PARM_DESC(bounce_interval,
2391 "Set the number of ticks to ignore suspend bounces");
2392 module_param(allow_ints, bool, 0444);
2393 MODULE_PARM_DESC(allow_ints, "Allow interrupts during BIOS calls");
2394 module_param(broken_psr, bool, 0444);
2395 MODULE_PARM_DESC(broken_psr, "BIOS has a broken GetPowerStatus call");
2396 module_param(realmode_power_off, bool, 0444);
2397 MODULE_PARM_DESC(realmode_power_off,
2398 "Switch to real mode before powering off");
2399 module_param(idle_threshold, int, 0444);
2400 MODULE_PARM_DESC(idle_threshold,
2401 "System idle percentage above which to make APM BIOS idle calls");
2402 module_param(idle_period, int, 0444);
2403 MODULE_PARM_DESC(idle_period,
2404 "Period (in sec/100) over which to caculate the idle percentage");
2405 module_param(smp, bool, 0444);
2406 MODULE_PARM_DESC(smp,
2407 "Set this to enable APM use on an SMP platform. Use with caution on older systems");
2408 MODULE_ALIAS_MISCDEV(APM_MINOR_DEV);