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);
1216 spin_lock(&user_list_lock);
1217 for (as = user_list; as != NULL; as = as->next) {
1218 as->suspend_wait = 0;
1219 as->suspend_result = err;
1221 spin_unlock(&user_list_lock);
1222 wake_up_interruptible(&apm_suspend_waitqueue);
1226 static void standby(void)
1230 local_irq_disable();
1231 device_power_down(PMSG_SUSPEND);
1234 err = set_system_power_state(APM_STATE_STANDBY);
1235 if ((err != APM_SUCCESS) && (err != APM_NO_ERROR))
1236 apm_error("standby", err);
1238 local_irq_disable();
1243 static apm_event_t get_event(void)
1246 apm_event_t event = APM_NO_EVENTS; /* silence gcc */
1247 apm_eventinfo_t info;
1249 static int notified;
1251 /* we don't use the eventinfo */
1252 error = apm_get_event(&event, &info);
1253 if (error == APM_SUCCESS)
1256 if ((error != APM_NO_EVENTS) && (notified++ == 0))
1257 apm_error("get_event", error);
1262 static void check_events(void)
1265 static unsigned long last_resume;
1266 static int ignore_bounce;
1268 while ((event = get_event()) != 0) {
1270 if (event <= NR_APM_EVENT_NAME)
1271 printk(KERN_DEBUG "apm: received %s notify\n",
1272 apm_event_name[event - 1]);
1274 printk(KERN_DEBUG "apm: received unknown "
1275 "event 0x%02x\n", event);
1278 && (time_after(jiffies, last_resume + bounce_interval)))
1282 case APM_SYS_STANDBY:
1283 case APM_USER_STANDBY:
1284 queue_event(event, NULL);
1285 if (standbys_pending <= 0)
1289 case APM_USER_SUSPEND:
1290 #ifdef CONFIG_APM_IGNORE_USER_SUSPEND
1291 if (apm_info.connection_version > 0x100)
1292 set_system_power_state(APM_STATE_REJECT);
1295 case APM_SYS_SUSPEND:
1296 if (ignore_bounce) {
1297 if (apm_info.connection_version > 0x100)
1298 set_system_power_state(APM_STATE_REJECT);
1302 * If we are already processing a SUSPEND,
1303 * then further SUSPEND events from the BIOS
1304 * will be ignored. We also return here to
1305 * cope with the fact that the Thinkpads keep
1306 * sending a SUSPEND event until something else
1309 if (ignore_sys_suspend)
1311 ignore_sys_suspend = 1;
1312 queue_event(event, NULL);
1313 if (suspends_pending <= 0)
1317 case APM_NORMAL_RESUME:
1318 case APM_CRITICAL_RESUME:
1319 case APM_STANDBY_RESUME:
1320 ignore_sys_suspend = 0;
1321 last_resume = jiffies;
1323 if ((event != APM_NORMAL_RESUME)
1324 || (ignore_normal_resume == 0)) {
1326 queue_event(event, NULL);
1328 ignore_normal_resume = 0;
1331 case APM_CAPABILITY_CHANGE:
1332 case APM_LOW_BATTERY:
1333 case APM_POWER_STATUS_CHANGE:
1334 queue_event(event, NULL);
1335 /* If needed, notify drivers here */
1338 case APM_UPDATE_TIME:
1341 case APM_CRITICAL_SUSPEND:
1343 * We are not allowed to reject a critical suspend.
1351 static void apm_event_handler(void)
1353 static int pending_count = 4;
1356 if ((standbys_pending > 0) || (suspends_pending > 0)) {
1357 if ((apm_info.connection_version > 0x100) &&
1358 (pending_count-- <= 0)) {
1361 printk(KERN_DEBUG "apm: setting state busy\n");
1362 err = set_system_power_state(APM_STATE_BUSY);
1364 apm_error("busy", err);
1372 * This is the APM thread main loop.
1375 static void apm_mainloop(void)
1377 DECLARE_WAITQUEUE(wait, current);
1379 add_wait_queue(&apm_waitqueue, &wait);
1380 set_current_state(TASK_INTERRUPTIBLE);
1382 schedule_timeout(APM_CHECK_TIMEOUT);
1383 if (kthread_should_stop())
1386 * Ok, check all events, check for idle (and mark us sleeping
1387 * so as not to count towards the load average)..
1389 set_current_state(TASK_INTERRUPTIBLE);
1390 apm_event_handler();
1392 remove_wait_queue(&apm_waitqueue, &wait);
1395 static int check_apm_user(struct apm_user *as, const char *func)
1397 if ((as == NULL) || (as->magic != APM_BIOS_MAGIC)) {
1398 printk(KERN_ERR "apm: %s passed bad filp\n", func);
1404 static ssize_t do_read(struct file *fp, char __user *buf, size_t count, loff_t *ppos)
1406 struct apm_user *as;
1410 as = fp->private_data;
1411 if (check_apm_user(as, "read"))
1413 if ((int)count < sizeof(apm_event_t))
1415 if ((queue_empty(as)) && (fp->f_flags & O_NONBLOCK))
1417 wait_event_interruptible(apm_waitqueue, !queue_empty(as));
1419 while ((i >= sizeof(event)) && !queue_empty(as)) {
1420 event = get_queued_event(as);
1421 if (copy_to_user(buf, &event, sizeof(event))) {
1427 case APM_SYS_SUSPEND:
1428 case APM_USER_SUSPEND:
1429 as->suspends_read++;
1432 case APM_SYS_STANDBY:
1433 case APM_USER_STANDBY:
1434 as->standbys_read++;
1437 buf += sizeof(event);
1442 if (signal_pending(current))
1443 return -ERESTARTSYS;
1447 static unsigned int do_poll(struct file *fp, poll_table *wait)
1449 struct apm_user *as;
1451 as = fp->private_data;
1452 if (check_apm_user(as, "poll"))
1454 poll_wait(fp, &apm_waitqueue, wait);
1455 if (!queue_empty(as))
1456 return POLLIN | POLLRDNORM;
1460 static int do_ioctl(struct inode *inode, struct file *filp,
1461 u_int cmd, u_long arg)
1463 struct apm_user *as;
1465 as = filp->private_data;
1466 if (check_apm_user(as, "ioctl"))
1468 if ((!as->suser) || (!as->writer))
1471 case APM_IOC_STANDBY:
1472 if (as->standbys_read > 0) {
1473 as->standbys_read--;
1474 as->standbys_pending--;
1477 queue_event(APM_USER_STANDBY, as);
1478 if (standbys_pending <= 0)
1481 case APM_IOC_SUSPEND:
1482 if (as->suspends_read > 0) {
1483 as->suspends_read--;
1484 as->suspends_pending--;
1487 queue_event(APM_USER_SUSPEND, as);
1488 if (suspends_pending <= 0) {
1491 as->suspend_wait = 1;
1492 wait_event_interruptible(apm_suspend_waitqueue,
1493 as->suspend_wait == 0);
1494 return as->suspend_result;
1503 static int do_release(struct inode *inode, struct file *filp)
1505 struct apm_user *as;
1507 as = filp->private_data;
1508 if (check_apm_user(as, "release"))
1510 filp->private_data = NULL;
1511 if (as->standbys_pending > 0) {
1512 standbys_pending -= as->standbys_pending;
1513 if (standbys_pending <= 0)
1516 if (as->suspends_pending > 0) {
1517 suspends_pending -= as->suspends_pending;
1518 if (suspends_pending <= 0)
1521 spin_lock(&user_list_lock);
1522 if (user_list == as)
1523 user_list = as->next;
1525 struct apm_user *as1;
1527 for (as1 = user_list;
1528 (as1 != NULL) && (as1->next != as);
1532 printk(KERN_ERR "apm: filp not in user list\n");
1534 as1->next = as->next;
1536 spin_unlock(&user_list_lock);
1541 static int do_open(struct inode *inode, struct file *filp)
1543 struct apm_user *as;
1545 as = kmalloc(sizeof(*as), GFP_KERNEL);
1547 printk(KERN_ERR "apm: cannot allocate struct of size %d bytes\n",
1551 as->magic = APM_BIOS_MAGIC;
1552 as->event_tail = as->event_head = 0;
1553 as->suspends_pending = as->standbys_pending = 0;
1554 as->suspends_read = as->standbys_read = 0;
1556 * XXX - this is a tiny bit broken, when we consider BSD
1557 * process accounting. If the device is opened by root, we
1558 * instantly flag that we used superuser privs. Who knows,
1559 * we might close the device immediately without doing a
1560 * privileged operation -- cevans
1562 as->suser = capable(CAP_SYS_ADMIN);
1563 as->writer = (filp->f_mode & FMODE_WRITE) == FMODE_WRITE;
1564 as->reader = (filp->f_mode & FMODE_READ) == FMODE_READ;
1565 spin_lock(&user_list_lock);
1566 as->next = user_list;
1568 spin_unlock(&user_list_lock);
1569 filp->private_data = as;
1573 static int proc_apm_show(struct seq_file *m, void *v)
1579 unsigned short ac_line_status = 0xff;
1580 unsigned short battery_status = 0xff;
1581 unsigned short battery_flag = 0xff;
1582 int percentage = -1;
1583 int time_units = -1;
1586 if ((num_online_cpus() == 1) &&
1587 !(error = apm_get_power_status(&bx, &cx, &dx))) {
1588 ac_line_status = (bx >> 8) & 0xff;
1589 battery_status = bx & 0xff;
1590 if ((cx & 0xff) != 0xff)
1591 percentage = cx & 0xff;
1593 if (apm_info.connection_version > 0x100) {
1594 battery_flag = (cx >> 8) & 0xff;
1596 units = (dx & 0x8000) ? "min" : "sec";
1597 time_units = dx & 0x7fff;
1601 /* Arguments, with symbols from linux/apm_bios.h. Information is
1602 from the Get Power Status (0x0a) call unless otherwise noted.
1604 0) Linux driver version (this will change if format changes)
1605 1) APM BIOS Version. Usually 1.0, 1.1 or 1.2.
1606 2) APM flags from APM Installation Check (0x00):
1607 bit 0: APM_16_BIT_SUPPORT
1608 bit 1: APM_32_BIT_SUPPORT
1609 bit 2: APM_IDLE_SLOWS_CLOCK
1610 bit 3: APM_BIOS_DISABLED
1611 bit 4: APM_BIOS_DISENGAGED
1615 0x02: On backup power (BIOS >= 1.1 only)
1622 0x04: Selected battery not present (BIOS >= 1.2 only)
1629 bit 7: No system battery
1631 6) Remaining battery life (percentage of charge):
1634 7) Remaining battery life (time units):
1635 Number of remaining minutes or seconds
1637 8) min = minutes; sec = seconds */
1639 seq_printf(m, "%s %d.%d 0x%02x 0x%02x 0x%02x 0x%02x %d%% %d %s\n",
1641 (apm_info.bios.version >> 8) & 0xff,
1642 apm_info.bios.version & 0xff,
1643 apm_info.bios.flags,
1653 static int proc_apm_open(struct inode *inode, struct file *file)
1655 return single_open(file, proc_apm_show, NULL);
1658 static const struct file_operations apm_file_ops = {
1659 .owner = THIS_MODULE,
1660 .open = proc_apm_open,
1662 .llseek = seq_lseek,
1663 .release = single_release,
1666 static int apm(void *unused)
1677 * This is to avoid random crashes at boot time during initialization
1678 * on SMP systems in case of "apm=power-off" mode. Seen on ASUS A7M266D.
1679 * Some bioses don't like being called from CPU != 0.
1680 * Method suggested by Ingo Molnar.
1682 set_cpus_allowed(current, cpumask_of_cpu(0));
1683 BUG_ON(smp_processor_id() != 0);
1686 if (apm_info.connection_version == 0) {
1687 apm_info.connection_version = apm_info.bios.version;
1688 if (apm_info.connection_version > 0x100) {
1690 * We only support BIOSs up to version 1.2
1692 if (apm_info.connection_version > 0x0102)
1693 apm_info.connection_version = 0x0102;
1694 error = apm_driver_version(&apm_info.connection_version);
1695 if (error != APM_SUCCESS) {
1696 apm_error("driver version", error);
1697 /* Fall back to an APM 1.0 connection. */
1698 apm_info.connection_version = 0x100;
1704 printk(KERN_INFO "apm: Connection version %d.%d\n",
1705 (apm_info.connection_version >> 8) & 0xff,
1706 apm_info.connection_version & 0xff);
1708 #ifdef CONFIG_APM_DO_ENABLE
1709 if (apm_info.bios.flags & APM_BIOS_DISABLED) {
1711 * This call causes my NEC UltraLite Versa 33/C to hang if it
1712 * is booted with PM disabled but not in the docking station.
1715 error = apm_enable_power_management(1);
1717 apm_error("enable power management", error);
1723 if ((apm_info.bios.flags & APM_BIOS_DISENGAGED)
1724 && (apm_info.connection_version > 0x0100)) {
1725 error = apm_engage_power_management(APM_DEVICE_ALL, 1);
1727 apm_error("engage power management", error);
1732 if (debug && (num_online_cpus() == 1 || smp)) {
1733 error = apm_get_power_status(&bx, &cx, &dx);
1735 printk(KERN_INFO "apm: power status not available\n");
1737 switch ((bx >> 8) & 0xff) {
1739 power_stat = "off line";
1742 power_stat = "on line";
1745 power_stat = "on backup power";
1748 power_stat = "unknown";
1751 switch (bx & 0xff) {
1759 bat_stat = "critical";
1762 bat_stat = "charging";
1765 bat_stat = "unknown";
1769 "apm: AC %s, battery status %s, battery life ",
1770 power_stat, bat_stat);
1771 if ((cx & 0xff) == 0xff)
1772 printk("unknown\n");
1774 printk("%d%%\n", cx & 0xff);
1775 if (apm_info.connection_version > 0x100) {
1777 "apm: battery flag 0x%02x, battery life ",
1780 printk("unknown\n");
1782 printk("%d %s\n", dx & 0x7fff,
1784 "minutes" : "seconds");
1789 /* Install our power off handler.. */
1791 pm_power_off = apm_power_off;
1793 if (num_online_cpus() == 1 || smp) {
1794 #if defined(CONFIG_APM_DISPLAY_BLANK) && defined(CONFIG_VT)
1795 console_blank_hook = apm_console_blank;
1798 #if defined(CONFIG_APM_DISPLAY_BLANK) && defined(CONFIG_VT)
1799 console_blank_hook = NULL;
1807 static int __init apm_setup(char *str)
1811 while ((str != NULL) && (*str != '\0')) {
1812 if (strncmp(str, "off", 3) == 0)
1814 if (strncmp(str, "on", 2) == 0)
1816 if ((strncmp(str, "bounce-interval=", 16) == 0) ||
1817 (strncmp(str, "bounce_interval=", 16) == 0))
1818 bounce_interval = simple_strtol(str + 16, NULL, 0);
1819 if ((strncmp(str, "idle-threshold=", 15) == 0) ||
1820 (strncmp(str, "idle_threshold=", 15) == 0))
1821 idle_threshold = simple_strtol(str + 15, NULL, 0);
1822 if ((strncmp(str, "idle-period=", 12) == 0) ||
1823 (strncmp(str, "idle_period=", 12) == 0))
1824 idle_period = simple_strtol(str + 12, NULL, 0);
1825 invert = (strncmp(str, "no-", 3) == 0) ||
1826 (strncmp(str, "no_", 3) == 0);
1829 if (strncmp(str, "debug", 5) == 0)
1831 if ((strncmp(str, "power-off", 9) == 0) ||
1832 (strncmp(str, "power_off", 9) == 0))
1833 power_off = !invert;
1834 if (strncmp(str, "smp", 3) == 0) {
1836 idle_threshold = 100;
1838 if ((strncmp(str, "allow-ints", 10) == 0) ||
1839 (strncmp(str, "allow_ints", 10) == 0))
1840 apm_info.allow_ints = !invert;
1841 if ((strncmp(str, "broken-psr", 10) == 0) ||
1842 (strncmp(str, "broken_psr", 10) == 0))
1843 apm_info.get_power_status_broken = !invert;
1844 if ((strncmp(str, "realmode-power-off", 18) == 0) ||
1845 (strncmp(str, "realmode_power_off", 18) == 0))
1846 apm_info.realmode_power_off = !invert;
1847 str = strchr(str, ',');
1849 str += strspn(str, ", \t");
1854 __setup("apm=", apm_setup);
1857 static const struct file_operations apm_bios_fops = {
1858 .owner = THIS_MODULE,
1863 .release = do_release,
1866 static struct miscdevice apm_device = {
1873 /* Simple "print if true" callback */
1874 static int __init print_if_true(const struct dmi_system_id *d)
1876 printk("%s\n", d->ident);
1881 * Some Bioses enable the PS/2 mouse (touchpad) at resume, even if it was
1882 * disabled before the suspend. Linux used to get terribly confused by that.
1884 static int __init broken_ps2_resume(const struct dmi_system_id *d)
1886 printk(KERN_INFO "%s machine detected. Mousepad Resume Bug "
1887 "workaround hopefully not needed.\n", d->ident);
1891 /* Some bioses have a broken protected mode poweroff and need to use realmode */
1892 static int __init set_realmode_power_off(const struct dmi_system_id *d)
1894 if (apm_info.realmode_power_off == 0) {
1895 apm_info.realmode_power_off = 1;
1896 printk(KERN_INFO "%s bios detected. "
1897 "Using realmode poweroff only.\n", d->ident);
1902 /* Some laptops require interrupts to be enabled during APM calls */
1903 static int __init set_apm_ints(const struct dmi_system_id *d)
1905 if (apm_info.allow_ints == 0) {
1906 apm_info.allow_ints = 1;
1907 printk(KERN_INFO "%s machine detected. "
1908 "Enabling interrupts during APM calls.\n", d->ident);
1913 /* Some APM bioses corrupt memory or just plain do not work */
1914 static int __init apm_is_horked(const struct dmi_system_id *d)
1916 if (apm_info.disabled == 0) {
1917 apm_info.disabled = 1;
1918 printk(KERN_INFO "%s machine detected. "
1919 "Disabling APM.\n", d->ident);
1924 static int __init apm_is_horked_d850md(const struct dmi_system_id *d)
1926 if (apm_info.disabled == 0) {
1927 apm_info.disabled = 1;
1928 printk(KERN_INFO "%s machine detected. "
1929 "Disabling APM.\n", d->ident);
1930 printk(KERN_INFO "This bug is fixed in bios P15 which is available for \n");
1931 printk(KERN_INFO "download from support.intel.com \n");
1936 /* Some APM bioses hang on APM idle calls */
1937 static int __init apm_likes_to_melt(const struct dmi_system_id *d)
1939 if (apm_info.forbid_idle == 0) {
1940 apm_info.forbid_idle = 1;
1941 printk(KERN_INFO "%s machine detected. "
1942 "Disabling APM idle calls.\n", d->ident);
1948 * Check for clue free BIOS implementations who use
1949 * the following QA technique
1951 * [ Write BIOS Code ]<------
1953 * < Does it Compile >----N--
1955 * < Does it Boot Win98 >-N--
1959 * Phoenix A04 08/24/2000 is known bad (Dell Inspiron 5000e)
1960 * Phoenix A07 09/29/2000 is known good (Dell Inspiron 5000)
1962 static int __init broken_apm_power(const struct dmi_system_id *d)
1964 apm_info.get_power_status_broken = 1;
1965 printk(KERN_WARNING "BIOS strings suggest APM bugs, "
1966 "disabling power status reporting.\n");
1971 * This bios swaps the APM minute reporting bytes over (Many sony laptops
1972 * have this problem).
1974 static int __init swab_apm_power_in_minutes(const struct dmi_system_id *d)
1976 apm_info.get_power_status_swabinminutes = 1;
1977 printk(KERN_WARNING "BIOS strings suggest APM reports battery life "
1978 "in minutes and wrong byte order.\n");
1982 static struct dmi_system_id __initdata apm_dmi_table[] = {
1985 KERN_WARNING "IBM T23 - BIOS 1.03b+ and controller firmware 1.02+ may be needed for Linux APM.",
1986 { DMI_MATCH(DMI_SYS_VENDOR, "IBM"),
1987 DMI_MATCH(DMI_BIOS_VERSION, "1AET38WW (1.01b)"), },
1989 { /* Handle problems with APM on the C600 */
1990 broken_ps2_resume, "Dell Latitude C600",
1991 { DMI_MATCH(DMI_SYS_VENDOR, "Dell"),
1992 DMI_MATCH(DMI_PRODUCT_NAME, "Latitude C600"), },
1994 { /* Allow interrupts during suspend on Dell Latitude laptops*/
1995 set_apm_ints, "Dell Latitude",
1996 { DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
1997 DMI_MATCH(DMI_PRODUCT_NAME, "Latitude C510"), }
2000 apm_is_horked, "Dell Inspiron 2500",
2001 { DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
2002 DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 2500"),
2003 DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2004 DMI_MATCH(DMI_BIOS_VERSION, "A11"), },
2006 { /* Allow interrupts during suspend on Dell Inspiron laptops*/
2007 set_apm_ints, "Dell Inspiron", {
2008 DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
2009 DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 4000"), },
2011 { /* Handle problems with APM on Inspiron 5000e */
2012 broken_apm_power, "Dell Inspiron 5000e",
2013 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2014 DMI_MATCH(DMI_BIOS_VERSION, "A04"),
2015 DMI_MATCH(DMI_BIOS_DATE, "08/24/2000"), },
2017 { /* Handle problems with APM on Inspiron 2500 */
2018 broken_apm_power, "Dell Inspiron 2500",
2019 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2020 DMI_MATCH(DMI_BIOS_VERSION, "A12"),
2021 DMI_MATCH(DMI_BIOS_DATE, "02/04/2002"), },
2024 apm_is_horked, "Dell Dimension 4100",
2025 { DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
2026 DMI_MATCH(DMI_PRODUCT_NAME, "XPS-Z"),
2027 DMI_MATCH(DMI_BIOS_VENDOR, "Intel Corp."),
2028 DMI_MATCH(DMI_BIOS_VERSION, "A11"), },
2030 { /* Allow interrupts during suspend on Compaq Laptops*/
2031 set_apm_ints, "Compaq 12XL125",
2032 { DMI_MATCH(DMI_SYS_VENDOR, "Compaq"),
2033 DMI_MATCH(DMI_PRODUCT_NAME, "Compaq PC"),
2034 DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2035 DMI_MATCH(DMI_BIOS_VERSION, "4.06"), },
2037 { /* Allow interrupts during APM or the clock goes slow */
2038 set_apm_ints, "ASUSTeK",
2039 { DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK Computer Inc."),
2040 DMI_MATCH(DMI_PRODUCT_NAME, "L8400K series Notebook PC"), },
2042 { /* APM blows on shutdown */
2043 apm_is_horked, "ABIT KX7-333[R]",
2044 { DMI_MATCH(DMI_BOARD_VENDOR, "ABIT"),
2045 DMI_MATCH(DMI_BOARD_NAME, "VT8367-8233A (KX7-333[R])"), },
2048 apm_is_horked, "Trigem Delhi3",
2049 { DMI_MATCH(DMI_SYS_VENDOR, "TriGem Computer, Inc"),
2050 DMI_MATCH(DMI_PRODUCT_NAME, "Delhi3"), },
2053 apm_is_horked, "Fujitsu-Siemens",
2054 { DMI_MATCH(DMI_BIOS_VENDOR, "hoenix/FUJITSU SIEMENS"),
2055 DMI_MATCH(DMI_BIOS_VERSION, "Version1.01"), },
2058 apm_is_horked_d850md, "Intel D850MD",
2059 { DMI_MATCH(DMI_BIOS_VENDOR, "Intel Corp."),
2060 DMI_MATCH(DMI_BIOS_VERSION, "MV85010A.86A.0016.P07.0201251536"), },
2063 apm_is_horked, "Intel D810EMO",
2064 { DMI_MATCH(DMI_BIOS_VENDOR, "Intel Corp."),
2065 DMI_MATCH(DMI_BIOS_VERSION, "MO81010A.86A.0008.P04.0004170800"), },
2068 apm_is_horked, "Dell XPS-Z",
2069 { DMI_MATCH(DMI_BIOS_VENDOR, "Intel Corp."),
2070 DMI_MATCH(DMI_BIOS_VERSION, "A11"),
2071 DMI_MATCH(DMI_PRODUCT_NAME, "XPS-Z"), },
2074 apm_is_horked, "Sharp PC-PJ/AX",
2075 { DMI_MATCH(DMI_SYS_VENDOR, "SHARP"),
2076 DMI_MATCH(DMI_PRODUCT_NAME, "PC-PJ/AX"),
2077 DMI_MATCH(DMI_BIOS_VENDOR, "SystemSoft"),
2078 DMI_MATCH(DMI_BIOS_VERSION, "Version R2.08"), },
2081 apm_is_horked, "Dell Inspiron 2500",
2082 { DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
2083 DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 2500"),
2084 DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2085 DMI_MATCH(DMI_BIOS_VERSION, "A11"), },
2087 { /* APM idle hangs */
2088 apm_likes_to_melt, "Jabil AMD",
2089 { DMI_MATCH(DMI_BIOS_VENDOR, "American Megatrends Inc."),
2090 DMI_MATCH(DMI_BIOS_VERSION, "0AASNP06"), },
2092 { /* APM idle hangs */
2093 apm_likes_to_melt, "AMI Bios",
2094 { DMI_MATCH(DMI_BIOS_VENDOR, "American Megatrends Inc."),
2095 DMI_MATCH(DMI_BIOS_VERSION, "0AASNP05"), },
2097 { /* Handle problems with APM on Sony Vaio PCG-N505X(DE) */
2098 swab_apm_power_in_minutes, "Sony VAIO",
2099 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2100 DMI_MATCH(DMI_BIOS_VERSION, "R0206H"),
2101 DMI_MATCH(DMI_BIOS_DATE, "08/23/99"), },
2103 { /* Handle problems with APM on Sony Vaio PCG-N505VX */
2104 swab_apm_power_in_minutes, "Sony VAIO",
2105 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2106 DMI_MATCH(DMI_BIOS_VERSION, "W2K06H0"),
2107 DMI_MATCH(DMI_BIOS_DATE, "02/03/00"), },
2109 { /* Handle problems with APM on Sony Vaio PCG-XG29 */
2110 swab_apm_power_in_minutes, "Sony VAIO",
2111 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2112 DMI_MATCH(DMI_BIOS_VERSION, "R0117A0"),
2113 DMI_MATCH(DMI_BIOS_DATE, "04/25/00"), },
2115 { /* Handle problems with APM on Sony Vaio PCG-Z600NE */
2116 swab_apm_power_in_minutes, "Sony VAIO",
2117 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2118 DMI_MATCH(DMI_BIOS_VERSION, "R0121Z1"),
2119 DMI_MATCH(DMI_BIOS_DATE, "05/11/00"), },
2121 { /* Handle problems with APM on Sony Vaio PCG-Z600NE */
2122 swab_apm_power_in_minutes, "Sony VAIO",
2123 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2124 DMI_MATCH(DMI_BIOS_VERSION, "WME01Z1"),
2125 DMI_MATCH(DMI_BIOS_DATE, "08/11/00"), },
2127 { /* Handle problems with APM on Sony Vaio PCG-Z600LEK(DE) */
2128 swab_apm_power_in_minutes, "Sony VAIO",
2129 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2130 DMI_MATCH(DMI_BIOS_VERSION, "R0206Z3"),
2131 DMI_MATCH(DMI_BIOS_DATE, "12/25/00"), },
2133 { /* Handle problems with APM on Sony Vaio PCG-Z505LS */
2134 swab_apm_power_in_minutes, "Sony VAIO",
2135 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2136 DMI_MATCH(DMI_BIOS_VERSION, "R0203D0"),
2137 DMI_MATCH(DMI_BIOS_DATE, "05/12/00"), },
2139 { /* Handle problems with APM on Sony Vaio PCG-Z505LS */
2140 swab_apm_power_in_minutes, "Sony VAIO",
2141 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2142 DMI_MATCH(DMI_BIOS_VERSION, "R0203Z3"),
2143 DMI_MATCH(DMI_BIOS_DATE, "08/25/00"), },
2145 { /* Handle problems with APM on Sony Vaio PCG-Z505LS (with updated BIOS) */
2146 swab_apm_power_in_minutes, "Sony VAIO",
2147 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2148 DMI_MATCH(DMI_BIOS_VERSION, "R0209Z3"),
2149 DMI_MATCH(DMI_BIOS_DATE, "05/12/01"), },
2151 { /* Handle problems with APM on Sony Vaio PCG-F104K */
2152 swab_apm_power_in_minutes, "Sony VAIO",
2153 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2154 DMI_MATCH(DMI_BIOS_VERSION, "R0204K2"),
2155 DMI_MATCH(DMI_BIOS_DATE, "08/28/00"), },
2158 { /* Handle problems with APM on Sony Vaio PCG-C1VN/C1VE */
2159 swab_apm_power_in_minutes, "Sony VAIO",
2160 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2161 DMI_MATCH(DMI_BIOS_VERSION, "R0208P1"),
2162 DMI_MATCH(DMI_BIOS_DATE, "11/09/00"), },
2164 { /* Handle problems with APM on Sony Vaio PCG-C1VE */
2165 swab_apm_power_in_minutes, "Sony VAIO",
2166 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2167 DMI_MATCH(DMI_BIOS_VERSION, "R0204P1"),
2168 DMI_MATCH(DMI_BIOS_DATE, "09/12/00"), },
2170 { /* Handle problems with APM on Sony Vaio PCG-C1VE */
2171 swab_apm_power_in_minutes, "Sony VAIO",
2172 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2173 DMI_MATCH(DMI_BIOS_VERSION, "WXPO1Z3"),
2174 DMI_MATCH(DMI_BIOS_DATE, "10/26/01"), },
2176 { /* broken PM poweroff bios */
2177 set_realmode_power_off, "Award Software v4.60 PGMA",
2178 { DMI_MATCH(DMI_BIOS_VENDOR, "Award Software International, Inc."),
2179 DMI_MATCH(DMI_BIOS_VERSION, "4.60 PGMA"),
2180 DMI_MATCH(DMI_BIOS_DATE, "134526184"), },
2183 /* Generic per vendor APM settings */
2185 { /* Allow interrupts during suspend on IBM laptops */
2186 set_apm_ints, "IBM",
2187 { DMI_MATCH(DMI_SYS_VENDOR, "IBM"), },
2194 * Just start the APM thread. We do NOT want to do APM BIOS
2195 * calls from anything but the APM thread, if for no other reason
2196 * than the fact that we don't trust the APM BIOS. This way,
2197 * most common APM BIOS problems that lead to protection errors
2198 * etc will have at least some level of being contained...
2200 * In short, if something bad happens, at least we have a choice
2201 * of just killing the apm thread..
2203 static int __init apm_init(void)
2205 struct proc_dir_entry *apm_proc;
2206 struct desc_struct *gdt;
2209 dmi_check_system(apm_dmi_table);
2211 if (apm_info.bios.version == 0 || paravirt_enabled()) {
2212 printk(KERN_INFO "apm: BIOS not found.\n");
2216 "apm: BIOS version %d.%d Flags 0x%02x (Driver version %s)\n",
2217 ((apm_info.bios.version >> 8) & 0xff),
2218 (apm_info.bios.version & 0xff),
2219 apm_info.bios.flags,
2221 if ((apm_info.bios.flags & APM_32_BIT_SUPPORT) == 0) {
2222 printk(KERN_INFO "apm: no 32 bit BIOS support\n");
2227 apm_info.allow_ints = 1;
2229 apm_info.get_power_status_broken = 1;
2230 if (realmode_power_off)
2231 apm_info.realmode_power_off = 1;
2232 /* User can override, but default is to trust DMI */
2233 if (apm_disabled != -1)
2234 apm_info.disabled = apm_disabled;
2237 * Fix for the Compaq Contura 3/25c which reports BIOS version 0.1
2238 * but is reportedly a 1.0 BIOS.
2240 if (apm_info.bios.version == 0x001)
2241 apm_info.bios.version = 0x100;
2243 /* BIOS < 1.2 doesn't set cseg_16_len */
2244 if (apm_info.bios.version < 0x102)
2245 apm_info.bios.cseg_16_len = 0; /* 64k */
2248 printk(KERN_INFO "apm: entry %x:%x cseg16 %x dseg %x",
2249 apm_info.bios.cseg, apm_info.bios.offset,
2250 apm_info.bios.cseg_16, apm_info.bios.dseg);
2251 if (apm_info.bios.version > 0x100)
2252 printk(" cseg len %x, dseg len %x",
2253 apm_info.bios.cseg_len,
2254 apm_info.bios.dseg_len);
2255 if (apm_info.bios.version > 0x101)
2256 printk(" cseg16 len %x", apm_info.bios.cseg_16_len);
2260 if (apm_info.disabled) {
2261 printk(KERN_NOTICE "apm: disabled on user request.\n");
2264 if ((num_online_cpus() > 1) && !power_off && !smp) {
2265 printk(KERN_NOTICE "apm: disabled - APM is not SMP safe.\n");
2266 apm_info.disabled = 1;
2269 if (pm_flags & PM_ACPI) {
2270 printk(KERN_NOTICE "apm: overridden by ACPI.\n");
2271 apm_info.disabled = 1;
2277 * Set up a segment that references the real mode segment 0x40
2278 * that extends up to the end of page zero (that we have reserved).
2279 * This is for buggy BIOS's that refer to (real mode) segment 0x40
2280 * even though they are called in protected mode.
2282 set_base(bad_bios_desc, __va((unsigned long)0x40 << 4));
2283 _set_limit((char *)&bad_bios_desc, 4095 - (0x40 << 4));
2286 * Set up the long jump entry point to the APM BIOS, which is called
2287 * from inline assembly.
2289 apm_bios_entry.offset = apm_info.bios.offset;
2290 apm_bios_entry.segment = APM_CS;
2293 * The APM 1.1 BIOS is supposed to provide limit information that it
2294 * recognizes. Many machines do this correctly, but many others do
2295 * not restrict themselves to their claimed limit. When this happens,
2296 * they will cause a segmentation violation in the kernel at boot time.
2297 * Most BIOS's, however, will respect a 64k limit, so we use that.
2299 * Note we only set APM segments on CPU zero, since we pin the APM
2302 gdt = get_cpu_gdt_table(0);
2303 set_base(gdt[APM_CS >> 3],
2304 __va((unsigned long)apm_info.bios.cseg << 4));
2305 set_base(gdt[APM_CS_16 >> 3],
2306 __va((unsigned long)apm_info.bios.cseg_16 << 4));
2307 set_base(gdt[APM_DS >> 3],
2308 __va((unsigned long)apm_info.bios.dseg << 4));
2310 apm_proc = create_proc_entry("apm", 0, NULL);
2312 apm_proc->proc_fops = &apm_file_ops;
2314 kapmd_task = kthread_create(apm, NULL, "kapmd");
2315 if (IS_ERR(kapmd_task)) {
2316 printk(KERN_ERR "apm: disabled - Unable to start kernel "
2318 err = PTR_ERR(kapmd_task);
2320 remove_proc_entry("apm", NULL);
2323 wake_up_process(kapmd_task);
2325 if (num_online_cpus() > 1 && !smp) {
2327 "apm: disabled - APM is not SMP safe (power off active).\n");
2332 * Note we don't actually care if the misc_device cannot be registered.
2333 * this driver can do its job without it, even if userspace can't
2334 * control it. just log the error
2336 if (misc_register(&apm_device))
2337 printk(KERN_WARNING "apm: Could not register misc device.\n");
2340 idle_period = (idle_period * HZ) / 100;
2341 if (idle_threshold < 100) {
2342 original_pm_idle = pm_idle;
2343 pm_idle = apm_cpu_idle;
2350 static void __exit apm_exit(void)
2355 pm_idle = original_pm_idle;
2357 * We are about to unload the current idle thread pm callback
2358 * (pm_idle), Wait for all processors to update cached/local
2359 * copies of pm_idle before proceeding.
2363 if (((apm_info.bios.flags & APM_BIOS_DISENGAGED) == 0)
2364 && (apm_info.connection_version > 0x0100)) {
2365 error = apm_engage_power_management(APM_DEVICE_ALL, 0);
2367 apm_error("disengage power management", error);
2369 misc_deregister(&apm_device);
2370 remove_proc_entry("apm", NULL);
2372 pm_power_off = NULL;
2374 kthread_stop(kapmd_task);
2377 pm_flags &= ~PM_APM;
2380 module_init(apm_init);
2381 module_exit(apm_exit);
2383 MODULE_AUTHOR("Stephen Rothwell");
2384 MODULE_DESCRIPTION("Advanced Power Management");
2385 MODULE_LICENSE("GPL");
2386 module_param(debug, bool, 0644);
2387 MODULE_PARM_DESC(debug, "Enable debug mode");
2388 module_param(power_off, bool, 0444);
2389 MODULE_PARM_DESC(power_off, "Enable power off");
2390 module_param(bounce_interval, int, 0444);
2391 MODULE_PARM_DESC(bounce_interval,
2392 "Set the number of ticks to ignore suspend bounces");
2393 module_param(allow_ints, bool, 0444);
2394 MODULE_PARM_DESC(allow_ints, "Allow interrupts during BIOS calls");
2395 module_param(broken_psr, bool, 0444);
2396 MODULE_PARM_DESC(broken_psr, "BIOS has a broken GetPowerStatus call");
2397 module_param(realmode_power_off, bool, 0444);
2398 MODULE_PARM_DESC(realmode_power_off,
2399 "Switch to real mode before powering off");
2400 module_param(idle_threshold, int, 0444);
2401 MODULE_PARM_DESC(idle_threshold,
2402 "System idle percentage above which to make APM BIOS idle calls");
2403 module_param(idle_period, int, 0444);
2404 MODULE_PARM_DESC(idle_period,
2405 "Period (in sec/100) over which to caculate the idle percentage");
2406 module_param(smp, bool, 0444);
2407 MODULE_PARM_DESC(smp,
2408 "Set this to enable APM use on an SMP platform. Use with caution on older systems");
2409 MODULE_ALIAS_MISCDEV(APM_MINOR_DEV);