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>
231 #include <asm/system.h>
232 #include <asm/uaccess.h>
233 #include <asm/desc.h>
234 #include <asm/i8253.h>
235 #include <asm/paravirt.h>
236 #include <asm/reboot.h>
238 #if defined(CONFIG_APM_DISPLAY_BLANK) && defined(CONFIG_VT)
239 extern int (*console_blank_hook)(int);
243 * The apm_bios device is one of the misc char devices.
244 * This is its minor number.
246 #define APM_MINOR_DEV 134
249 * See Documentation/Config.help for the configuration options.
251 * Various options can be changed at boot time as follows:
252 * (We allow underscores for compatibility with the modules code)
253 * apm=on/off enable/disable APM
254 * [no-]allow[-_]ints allow interrupts during BIOS calls
255 * [no-]broken[-_]psr BIOS has a broken GetPowerStatus call
256 * [no-]realmode[-_]power[-_]off switch to real mode before
258 * [no-]debug log some debugging messages
259 * [no-]power[-_]off power off on shutdown
260 * [no-]smp Use apm even on an SMP box
261 * bounce[-_]interval=<n> number of ticks to ignore suspend
263 * idle[-_]threshold=<n> System idle percentage above which to
264 * make APM BIOS idle calls. Set it to
266 * idle[-_]period=<n> Period (in 1/100s of a second) over
267 * which the idle percentage is
271 /* KNOWN PROBLEM MACHINES:
273 * U: TI 4000M TravelMate: BIOS is *NOT* APM compliant
274 * [Confirmed by TI representative]
275 * ?: ACER 486DX4/75: uses dseg 0040, in violation of APM specification
276 * [Confirmed by BIOS disassembly]
277 * [This may work now ...]
278 * P: Toshiba 1950S: battery life information only gets updated after resume
279 * P: Midwest Micro Soundbook Elite DX2/66 monochrome: screen blanking
280 * broken in BIOS [Reported by Garst R. Reese <reese@isn.net>]
281 * ?: AcerNote-950: oops on reading /proc/apm - workaround is a WIP
282 * Neale Banks <neale@lowendale.com.au> December 2000
284 * Legend: U = unusable with APM patches
285 * P = partially usable with APM patches
289 * Define as 1 to make the driver always call the APM BIOS busy
290 * routine even if the clock was not reported as slowed by the
291 * idle routine. Otherwise, define as 0.
293 #define ALWAYS_CALL_BUSY 1
296 * Define to make the APM BIOS calls zero all data segment registers (so
297 * that an incorrect BIOS implementation will cause a kernel panic if it
298 * tries to write to arbitrary memory).
300 #define APM_ZERO_SEGS
305 * Define to re-initialize the interrupt 0 timer to 100 Hz after a suspend.
306 * This patched by Chad Miller <cmiller@surfsouth.com>, original code by
307 * David Chen <chen@ctpa04.mit.edu>
309 #undef INIT_TIMER_AFTER_SUSPEND
311 #ifdef INIT_TIMER_AFTER_SUSPEND
312 #include <linux/timex.h>
314 #include <linux/delay.h>
318 * Need to poll the APM BIOS every second
320 #define APM_CHECK_TIMEOUT (HZ)
323 * Ignore suspend events for this amount of time after a resume
325 #define DEFAULT_BOUNCE_INTERVAL (3 * HZ)
328 * Maximum number of events stored
330 #define APM_MAX_EVENTS 20
333 * The per-file APM data
337 struct apm_user * next;
338 unsigned int suser: 1;
339 unsigned int writer: 1;
340 unsigned int reader: 1;
341 unsigned int suspend_wait: 1;
343 int suspends_pending;
344 int standbys_pending;
349 apm_event_t events[APM_MAX_EVENTS];
353 * The magic number in apm_user
355 #define APM_BIOS_MAGIC 0x4101
358 * idle percentage above which bios idle calls are done
360 #ifdef CONFIG_APM_CPU_IDLE
361 #define DEFAULT_IDLE_THRESHOLD 95
363 #define DEFAULT_IDLE_THRESHOLD 100
365 #define DEFAULT_IDLE_PERIOD (100 / 3)
371 unsigned long offset;
372 unsigned short segment;
374 static int clock_slowed;
375 static int idle_threshold __read_mostly = DEFAULT_IDLE_THRESHOLD;
376 static int idle_period __read_mostly = DEFAULT_IDLE_PERIOD;
377 static int set_pm_idle;
378 static int suspends_pending;
379 static int standbys_pending;
380 static int ignore_sys_suspend;
381 static int ignore_normal_resume;
382 static int bounce_interval __read_mostly = DEFAULT_BOUNCE_INTERVAL;
384 static int debug __read_mostly;
385 static int smp __read_mostly;
386 static int apm_disabled = -1;
388 static int power_off;
390 static int power_off = 1;
392 #ifdef CONFIG_APM_REAL_MODE_POWER_OFF
393 static int realmode_power_off = 1;
395 static int realmode_power_off;
397 #ifdef CONFIG_APM_ALLOW_INTS
398 static int allow_ints = 1;
400 static int allow_ints;
402 static int broken_psr;
404 static DECLARE_WAIT_QUEUE_HEAD(apm_waitqueue);
405 static DECLARE_WAIT_QUEUE_HEAD(apm_suspend_waitqueue);
406 static struct apm_user * user_list;
407 static DEFINE_SPINLOCK(user_list_lock);
408 static const struct desc_struct bad_bios_desc = { 0, 0x00409200 };
410 static const char driver_version[] = "1.16ac"; /* no spaces */
412 static struct task_struct *kapmd_task;
415 * APM event names taken from the APM 1.2 specification. These are
416 * the message codes that the BIOS uses to tell us about events
418 static const char * const apm_event_name[] = {
424 "power status change",
429 "system standby resume",
430 "capabilities change"
432 #define NR_APM_EVENT_NAME ARRAY_SIZE(apm_event_name)
434 typedef struct lookup_t {
440 * The BIOS returns a set of standard error codes in AX when the
444 static const lookup_t error_table[] = {
445 /* N/A { APM_SUCCESS, "Operation succeeded" }, */
446 { APM_DISABLED, "Power management disabled" },
447 { APM_CONNECTED, "Real mode interface already connected" },
448 { APM_NOT_CONNECTED, "Interface not connected" },
449 { APM_16_CONNECTED, "16 bit interface already connected" },
450 /* N/A { APM_16_UNSUPPORTED, "16 bit interface not supported" }, */
451 { APM_32_CONNECTED, "32 bit interface already connected" },
452 { APM_32_UNSUPPORTED, "32 bit interface not supported" },
453 { APM_BAD_DEVICE, "Unrecognized device ID" },
454 { APM_BAD_PARAM, "Parameter out of range" },
455 { APM_NOT_ENGAGED, "Interface not engaged" },
456 { APM_BAD_FUNCTION, "Function not supported" },
457 { APM_RESUME_DISABLED, "Resume timer disabled" },
458 { APM_BAD_STATE, "Unable to enter requested state" },
459 /* N/A { APM_NO_EVENTS, "No events pending" }, */
460 { APM_NO_ERROR, "BIOS did not set a return code" },
461 { APM_NOT_PRESENT, "No APM present" }
463 #define ERROR_COUNT ARRAY_SIZE(error_table)
466 * apm_error - display an APM error
467 * @str: information string
468 * @err: APM BIOS return code
470 * Write a meaningful log entry to the kernel log in the event of
474 static void apm_error(char *str, int err)
478 for (i = 0; i < ERROR_COUNT; i++)
479 if (error_table[i].key == err) break;
481 printk(KERN_NOTICE "apm: %s: %s\n", str, error_table[i].msg);
483 printk(KERN_NOTICE "apm: %s: unknown error code %#2.2x\n",
488 * Lock APM functionality to physical CPU 0
493 static cpumask_t apm_save_cpus(void)
495 cpumask_t x = current->cpus_allowed;
496 /* Some bioses don't like being called from CPU != 0 */
497 set_cpus_allowed(current, cpumask_of_cpu(0));
498 BUG_ON(smp_processor_id() != 0);
502 static inline void apm_restore_cpus(cpumask_t mask)
504 set_cpus_allowed(current, mask);
510 * No CPU lockdown needed on a uniprocessor
513 #define apm_save_cpus() (current->cpus_allowed)
514 #define apm_restore_cpus(x) (void)(x)
519 * These are the actual BIOS calls. Depending on APM_ZERO_SEGS and
520 * apm_info.allow_ints, we are being really paranoid here! Not only
521 * are interrupts disabled, but all the segment registers (except SS)
522 * are saved and zeroed this means that if the BIOS tries to reference
523 * any data without explicitly loading the segment registers, the kernel
524 * will fault immediately rather than have some unforeseen circumstances
525 * for the rest of the kernel. And it will be very obvious! :-) Doing
526 * this depends on CS referring to the same physical memory as DS so that
527 * DS can be zeroed before the call. Unfortunately, we can't do anything
528 * about the stack segment/pointer. Also, we tell the compiler that
529 * everything could change.
531 * Also, we KNOW that for the non error case of apm_bios_call, there
532 * is no useful data returned in the low order 8 bits of eax.
535 static inline unsigned long __apm_irq_save(void)
538 local_save_flags(flags);
539 if (apm_info.allow_ints) {
540 if (irqs_disabled_flags(flags))
548 #define apm_irq_save(flags) \
549 do { flags = __apm_irq_save(); } while (0)
551 static inline void apm_irq_restore(unsigned long flags)
553 if (irqs_disabled_flags(flags))
555 else if (irqs_disabled())
560 # define APM_DECL_SEGS \
561 unsigned int saved_fs; unsigned int saved_gs;
562 # define APM_DO_SAVE_SEGS \
563 savesegment(fs, saved_fs); savesegment(gs, saved_gs)
564 # define APM_DO_RESTORE_SEGS \
565 loadsegment(fs, saved_fs); loadsegment(gs, saved_gs)
567 # define APM_DECL_SEGS
568 # define APM_DO_SAVE_SEGS
569 # define APM_DO_RESTORE_SEGS
573 * apm_bios_call - Make an APM BIOS 32bit call
574 * @func: APM function to execute
575 * @ebx_in: EBX register for call entry
576 * @ecx_in: ECX register for call entry
577 * @eax: EAX register return
578 * @ebx: EBX register return
579 * @ecx: ECX register return
580 * @edx: EDX register return
581 * @esi: ESI register return
583 * Make an APM call using the 32bit protected mode interface. The
584 * caller is responsible for knowing if APM BIOS is configured and
585 * enabled. This call can disable interrupts for a long period of
586 * time on some laptops. The return value is in AH and the carry
587 * flag is loaded into AL. If there is an error, then the error
588 * code is returned in AH (bits 8-15 of eax) and this function
592 static u8 apm_bios_call(u32 func, u32 ebx_in, u32 ecx_in,
593 u32 *eax, u32 *ebx, u32 *ecx, u32 *edx, u32 *esi)
599 struct desc_struct save_desc_40;
600 struct desc_struct *gdt;
602 cpus = apm_save_cpus();
605 gdt = get_cpu_gdt_table(cpu);
606 save_desc_40 = gdt[0x40 / 8];
607 gdt[0x40 / 8] = bad_bios_desc;
611 apm_bios_call_asm(func, ebx_in, ecx_in, eax, ebx, ecx, edx, esi);
613 apm_irq_restore(flags);
614 gdt[0x40 / 8] = save_desc_40;
616 apm_restore_cpus(cpus);
622 * apm_bios_call_simple - make a simple APM BIOS 32bit call
623 * @func: APM function to invoke
624 * @ebx_in: EBX register value for BIOS call
625 * @ecx_in: ECX register value for BIOS call
626 * @eax: EAX register on return from the BIOS call
628 * Make a BIOS call that returns one value only, or just status.
629 * If there is an error, then the error code is returned in AH
630 * (bits 8-15 of eax) and this function returns non-zero. This is
631 * used for simpler BIOS operations. This call may hold interrupts
632 * off for a long time on some laptops.
635 static u8 apm_bios_call_simple(u32 func, u32 ebx_in, u32 ecx_in, u32 *eax)
642 struct desc_struct save_desc_40;
643 struct desc_struct *gdt;
645 cpus = apm_save_cpus();
648 gdt = get_cpu_gdt_table(cpu);
649 save_desc_40 = gdt[0x40 / 8];
650 gdt[0x40 / 8] = bad_bios_desc;
654 error = apm_bios_call_simple_asm(func, ebx_in, ecx_in, eax);
656 apm_irq_restore(flags);
657 gdt[0x40 / 8] = save_desc_40;
659 apm_restore_cpus(cpus);
664 * apm_driver_version - APM driver version
665 * @val: loaded with the APM version on return
667 * Retrieve the APM version supported by the BIOS. This is only
668 * supported for APM 1.1 or higher. An error indicates APM 1.0 is
671 * On entry val should point to a value indicating the APM driver
672 * version with the high byte being the major and the low byte the
673 * minor number both in BCD
675 * On return it will hold the BIOS revision supported in the
679 static int apm_driver_version(u_short *val)
683 if (apm_bios_call_simple(APM_FUNC_VERSION, 0, *val, &eax))
684 return (eax >> 8) & 0xff;
690 * apm_get_event - get an APM event from the BIOS
691 * @event: pointer to the event
692 * @info: point to the event information
694 * The APM BIOS provides a polled information for event
695 * reporting. The BIOS expects to be polled at least every second
696 * when events are pending. When a message is found the caller should
697 * poll until no more messages are present. However, this causes
698 * problems on some laptops where a suspend event notification is
699 * not cleared until it is acknowledged.
701 * Additional information is returned in the info pointer, providing
702 * that APM 1.2 is in use. If no messges are pending the value 0x80
703 * is returned (No power management events pending).
706 static int apm_get_event(apm_event_t *event, apm_eventinfo_t *info)
713 if (apm_bios_call(APM_FUNC_GET_EVENT, 0, 0, &eax, &ebx, &ecx,
715 return (eax >> 8) & 0xff;
717 if (apm_info.connection_version < 0x0102)
718 *info = ~0; /* indicate info not valid */
725 * set_power_state - set the power management state
726 * @what: which items to transition
727 * @state: state to transition to
729 * Request an APM change of state for one or more system devices. The
730 * processor state must be transitioned last of all. what holds the
731 * class of device in the upper byte and the device number (0xFF for
732 * all) for the object to be transitioned.
734 * The state holds the state to transition to, which may in fact
735 * be an acceptance of a BIOS requested state change.
738 static int set_power_state(u_short what, u_short state)
742 if (apm_bios_call_simple(APM_FUNC_SET_STATE, what, state, &eax))
743 return (eax >> 8) & 0xff;
748 * set_system_power_state - set system wide power state
749 * @state: which state to enter
751 * Transition the entire system into a new APM power state.
754 static int set_system_power_state(u_short state)
756 return set_power_state(APM_DEVICE_ALL, state);
760 * apm_do_idle - perform power saving
762 * This function notifies the BIOS that the processor is (in the view
763 * of the OS) idle. It returns -1 in the event that the BIOS refuses
764 * to handle the idle request. On a success the function returns 1
765 * if the BIOS did clock slowing or 0 otherwise.
768 static int apm_do_idle(void)
775 polling = !!(current_thread_info()->status & TS_POLLING);
777 current_thread_info()->status &= ~TS_POLLING;
779 * TS_POLLING-cleared state must be visible before we
784 if (!need_resched()) {
786 ret = apm_bios_call_simple(APM_FUNC_IDLE, 0, 0, &eax);
789 current_thread_info()->status |= TS_POLLING;
795 static unsigned long t;
797 /* This always fails on some SMP boards running UP kernels.
798 * Only report the failure the first 5 times.
802 printk(KERN_DEBUG "apm_do_idle failed (%d)\n",
808 clock_slowed = (apm_info.bios.flags & APM_IDLE_SLOWS_CLOCK) != 0;
813 * apm_do_busy - inform the BIOS the CPU is busy
815 * Request that the BIOS brings the CPU back to full performance.
818 static void apm_do_busy(void)
822 if (clock_slowed || ALWAYS_CALL_BUSY) {
823 (void) apm_bios_call_simple(APM_FUNC_BUSY, 0, 0, &dummy);
829 * If no process has really been interested in
830 * the CPU for some time, we want to call BIOS
831 * power management - we probably want
834 #define IDLE_CALC_LIMIT (HZ * 100)
835 #define IDLE_LEAKY_MAX 16
837 static void (*original_pm_idle)(void) __read_mostly;
840 * apm_cpu_idle - cpu idling for APM capable Linux
842 * This is the idling function the kernel executes when APM is available. It
843 * tries to do BIOS powermanagement based on the average system idle time.
844 * Furthermore it calls the system default idle routine.
847 static void apm_cpu_idle(void)
849 static int use_apm_idle; /* = 0 */
850 static unsigned int last_jiffies; /* = 0 */
851 static unsigned int last_stime; /* = 0 */
853 int apm_idle_done = 0;
854 unsigned int jiffies_since_last_check = jiffies - last_jiffies;
858 if (jiffies_since_last_check > IDLE_CALC_LIMIT) {
860 last_jiffies = jiffies;
861 last_stime = current->stime;
862 } else if (jiffies_since_last_check > idle_period) {
863 unsigned int idle_percentage;
865 idle_percentage = current->stime - last_stime;
866 idle_percentage *= 100;
867 idle_percentage /= jiffies_since_last_check;
868 use_apm_idle = (idle_percentage > idle_threshold);
869 if (apm_info.forbid_idle)
871 last_jiffies = jiffies;
872 last_stime = current->stime;
875 bucket = IDLE_LEAKY_MAX;
877 while (!need_resched()) {
882 switch (apm_do_idle()) {
883 case 0: apm_idle_done = 1;
886 bucket = IDLE_LEAKY_MAX;
894 case 1: apm_idle_done = 1;
896 default: /* BIOS refused */
900 if (original_pm_idle)
904 jiffies_since_last_check = jiffies - last_jiffies;
905 if (jiffies_since_last_check > idle_period)
914 * apm_power_off - ask the BIOS to power off
916 * Handle the power off sequence. This is the one piece of code we
917 * will execute even on SMP machines. In order to deal with BIOS
918 * bugs we support real mode APM BIOS power off calls. We also make
919 * the SMP call on CPU0 as some systems will only honour this call
920 * on their first cpu.
923 static void apm_power_off(void)
925 unsigned char po_bios_call[] = {
926 0xb8, 0x00, 0x10, /* movw $0x1000,ax */
927 0x8e, 0xd0, /* movw ax,ss */
928 0xbc, 0x00, 0xf0, /* movw $0xf000,sp */
929 0xb8, 0x07, 0x53, /* movw $0x5307,ax */
930 0xbb, 0x01, 0x00, /* movw $0x0001,bx */
931 0xb9, 0x03, 0x00, /* movw $0x0003,cx */
932 0xcd, 0x15 /* int $0x15 */
935 /* Some bioses don't like being called from CPU != 0 */
936 if (apm_info.realmode_power_off)
938 (void)apm_save_cpus();
939 machine_real_restart(po_bios_call, sizeof(po_bios_call));
942 (void) set_system_power_state(APM_STATE_OFF);
945 #ifdef CONFIG_APM_DO_ENABLE
948 * apm_enable_power_management - enable BIOS APM power management
949 * @enable: enable yes/no
951 * Enable or disable the APM BIOS power services.
954 static int apm_enable_power_management(int enable)
958 if ((enable == 0) && (apm_info.bios.flags & APM_BIOS_DISENGAGED))
959 return APM_NOT_ENGAGED;
960 if (apm_bios_call_simple(APM_FUNC_ENABLE_PM, APM_DEVICE_BALL,
962 return (eax >> 8) & 0xff;
964 apm_info.bios.flags &= ~APM_BIOS_DISABLED;
966 apm_info.bios.flags |= APM_BIOS_DISABLED;
972 * apm_get_power_status - get current power state
973 * @status: returned status
975 * @life: estimated life
977 * Obtain the current power status from the APM BIOS. We return a
978 * status which gives the rough battery status, and current power
979 * source. The bat value returned give an estimate as a percentage
980 * of life and a status value for the battery. The estimated life
981 * if reported is a lifetime in secodnds/minutes at current powwer
985 static int apm_get_power_status(u_short *status, u_short *bat, u_short *life)
993 if (apm_info.get_power_status_broken)
994 return APM_32_UNSUPPORTED;
995 if (apm_bios_call(APM_FUNC_GET_STATUS, APM_DEVICE_ALL, 0,
996 &eax, &ebx, &ecx, &edx, &dummy))
997 return (eax >> 8) & 0xff;
1000 if (apm_info.get_power_status_swabinminutes) {
1001 *life = swab16((u16)edx);
1009 static int apm_get_battery_status(u_short which, u_short *status,
1010 u_short *bat, u_short *life, u_short *nbat)
1018 if (apm_info.connection_version < 0x0102) {
1019 /* pretend we only have one battery. */
1021 return APM_BAD_DEVICE;
1023 return apm_get_power_status(status, bat, life);
1026 if (apm_bios_call(APM_FUNC_GET_STATUS, (0x8000 | (which)), 0, &eax,
1027 &ebx, &ecx, &edx, &esi))
1028 return (eax >> 8) & 0xff;
1038 * apm_engage_power_management - enable PM on a device
1039 * @device: identity of device
1042 * Activate or deactive power management on either a specific device
1043 * or the entire system (%APM_DEVICE_ALL).
1046 static int apm_engage_power_management(u_short device, int enable)
1050 if ((enable == 0) && (device == APM_DEVICE_ALL)
1051 && (apm_info.bios.flags & APM_BIOS_DISABLED))
1052 return APM_DISABLED;
1053 if (apm_bios_call_simple(APM_FUNC_ENGAGE_PM, device, enable, &eax))
1054 return (eax >> 8) & 0xff;
1055 if (device == APM_DEVICE_ALL) {
1057 apm_info.bios.flags &= ~APM_BIOS_DISENGAGED;
1059 apm_info.bios.flags |= APM_BIOS_DISENGAGED;
1064 #if defined(CONFIG_APM_DISPLAY_BLANK) && defined(CONFIG_VT)
1067 * apm_console_blank - blank the display
1070 * Attempt to blank the console, firstly by blanking just video device
1071 * zero, and if that fails (some BIOSes don't support it) then it blanks
1072 * all video devices. Typically the BIOS will do laptop backlight and
1073 * monitor powerdown for us.
1076 static int apm_console_blank(int blank)
1078 int error = APM_NOT_ENGAGED; /* silence gcc */
1081 static const u_short dev[3] = { 0x100, 0x1FF, 0x101 };
1083 state = blank ? APM_STATE_STANDBY : APM_STATE_READY;
1085 for (i = 0; i < ARRAY_SIZE(dev); i++) {
1086 error = set_power_state(dev[i], state);
1088 if ((error == APM_SUCCESS) || (error == APM_NO_ERROR))
1091 if (error == APM_NOT_ENGAGED)
1095 if (error == APM_NOT_ENGAGED) {
1099 eng_error = apm_engage_power_management(APM_DEVICE_ALL, 1);
1101 apm_error("set display", error);
1102 apm_error("engage interface", eng_error);
1105 return apm_console_blank(blank);
1108 apm_error("set display", error);
1113 static int queue_empty(struct apm_user *as)
1115 return as->event_head == as->event_tail;
1118 static apm_event_t get_queued_event(struct apm_user *as)
1120 if (++as->event_tail >= APM_MAX_EVENTS)
1122 return as->events[as->event_tail];
1125 static void queue_event(apm_event_t event, struct apm_user *sender)
1127 struct apm_user * as;
1129 spin_lock(&user_list_lock);
1130 if (user_list == NULL)
1132 for (as = user_list; as != NULL; as = as->next) {
1133 if ((as == sender) || (!as->reader))
1135 if (++as->event_head >= APM_MAX_EVENTS)
1138 if (as->event_head == as->event_tail) {
1139 static int notified;
1141 if (notified++ == 0)
1142 printk(KERN_ERR "apm: an event queue overflowed\n");
1143 if (++as->event_tail >= APM_MAX_EVENTS)
1146 as->events[as->event_head] = event;
1147 if ((!as->suser) || (!as->writer))
1150 case APM_SYS_SUSPEND:
1151 case APM_USER_SUSPEND:
1152 as->suspends_pending++;
1156 case APM_SYS_STANDBY:
1157 case APM_USER_STANDBY:
1158 as->standbys_pending++;
1163 wake_up_interruptible(&apm_waitqueue);
1165 spin_unlock(&user_list_lock);
1168 static void reinit_timer(void)
1170 #ifdef INIT_TIMER_AFTER_SUSPEND
1171 unsigned long flags;
1173 spin_lock_irqsave(&i8253_lock, flags);
1174 /* set the clock to HZ */
1175 outb_p(0x34, PIT_MODE); /* binary, mode 2, LSB/MSB, ch 0 */
1177 outb_p(LATCH & 0xff, PIT_CH0); /* LSB */
1179 outb(LATCH >> 8, PIT_CH0); /* MSB */
1181 spin_unlock_irqrestore(&i8253_lock, flags);
1185 static int suspend(int vetoable)
1188 struct apm_user *as;
1190 if (pm_send_all(PM_SUSPEND, (void *)3)) {
1193 if (apm_info.connection_version > 0x100)
1194 set_system_power_state(APM_STATE_REJECT);
1196 ignore_sys_suspend = 0;
1197 printk(KERN_WARNING "apm: suspend was vetoed.\n");
1200 printk(KERN_CRIT "apm: suspend was vetoed, but suspending anyway.\n");
1203 device_suspend(PMSG_SUSPEND);
1204 local_irq_disable();
1205 device_power_down(PMSG_SUSPEND);
1209 save_processor_state();
1210 err = set_system_power_state(APM_STATE_SUSPEND);
1211 ignore_normal_resume = 1;
1212 restore_processor_state();
1214 local_irq_disable();
1217 if (err == APM_NO_ERROR)
1219 if (err != APM_SUCCESS)
1220 apm_error("suspend", err);
1221 err = (err == APM_SUCCESS) ? 0 : -EIO;
1225 pm_send_all(PM_RESUME, (void *)0);
1226 queue_event(APM_NORMAL_RESUME, NULL);
1228 spin_lock(&user_list_lock);
1229 for (as = user_list; as != NULL; as = as->next) {
1230 as->suspend_wait = 0;
1231 as->suspend_result = err;
1233 spin_unlock(&user_list_lock);
1234 wake_up_interruptible(&apm_suspend_waitqueue);
1238 static void standby(void)
1242 local_irq_disable();
1243 device_power_down(PMSG_SUSPEND);
1246 err = set_system_power_state(APM_STATE_STANDBY);
1247 if ((err != APM_SUCCESS) && (err != APM_NO_ERROR))
1248 apm_error("standby", err);
1250 local_irq_disable();
1255 static apm_event_t get_event(void)
1258 apm_event_t event = APM_NO_EVENTS; /* silence gcc */
1259 apm_eventinfo_t info;
1261 static int notified;
1263 /* we don't use the eventinfo */
1264 error = apm_get_event(&event, &info);
1265 if (error == APM_SUCCESS)
1268 if ((error != APM_NO_EVENTS) && (notified++ == 0))
1269 apm_error("get_event", error);
1274 static void check_events(void)
1277 static unsigned long last_resume;
1278 static int ignore_bounce;
1280 while ((event = get_event()) != 0) {
1282 if (event <= NR_APM_EVENT_NAME)
1283 printk(KERN_DEBUG "apm: received %s notify\n",
1284 apm_event_name[event - 1]);
1286 printk(KERN_DEBUG "apm: received unknown "
1287 "event 0x%02x\n", event);
1290 && ((jiffies - last_resume) > bounce_interval))
1294 case APM_SYS_STANDBY:
1295 case APM_USER_STANDBY:
1296 queue_event(event, NULL);
1297 if (standbys_pending <= 0)
1301 case APM_USER_SUSPEND:
1302 #ifdef CONFIG_APM_IGNORE_USER_SUSPEND
1303 if (apm_info.connection_version > 0x100)
1304 set_system_power_state(APM_STATE_REJECT);
1307 case APM_SYS_SUSPEND:
1308 if (ignore_bounce) {
1309 if (apm_info.connection_version > 0x100)
1310 set_system_power_state(APM_STATE_REJECT);
1314 * If we are already processing a SUSPEND,
1315 * then further SUSPEND events from the BIOS
1316 * will be ignored. We also return here to
1317 * cope with the fact that the Thinkpads keep
1318 * sending a SUSPEND event until something else
1321 if (ignore_sys_suspend)
1323 ignore_sys_suspend = 1;
1324 queue_event(event, NULL);
1325 if (suspends_pending <= 0)
1329 case APM_NORMAL_RESUME:
1330 case APM_CRITICAL_RESUME:
1331 case APM_STANDBY_RESUME:
1332 ignore_sys_suspend = 0;
1333 last_resume = jiffies;
1335 if ((event != APM_NORMAL_RESUME)
1336 || (ignore_normal_resume == 0)) {
1338 pm_send_all(PM_RESUME, (void *)0);
1339 queue_event(event, NULL);
1341 ignore_normal_resume = 0;
1344 case APM_CAPABILITY_CHANGE:
1345 case APM_LOW_BATTERY:
1346 case APM_POWER_STATUS_CHANGE:
1347 queue_event(event, NULL);
1348 /* If needed, notify drivers here */
1351 case APM_UPDATE_TIME:
1354 case APM_CRITICAL_SUSPEND:
1356 * We are not allowed to reject a critical suspend.
1364 static void apm_event_handler(void)
1366 static int pending_count = 4;
1369 if ((standbys_pending > 0) || (suspends_pending > 0)) {
1370 if ((apm_info.connection_version > 0x100) &&
1371 (pending_count-- <= 0)) {
1374 printk(KERN_DEBUG "apm: setting state busy\n");
1375 err = set_system_power_state(APM_STATE_BUSY);
1377 apm_error("busy", err);
1385 * This is the APM thread main loop.
1388 static void apm_mainloop(void)
1390 DECLARE_WAITQUEUE(wait, current);
1392 add_wait_queue(&apm_waitqueue, &wait);
1393 set_current_state(TASK_INTERRUPTIBLE);
1395 schedule_timeout(APM_CHECK_TIMEOUT);
1396 if (kthread_should_stop())
1399 * Ok, check all events, check for idle (and mark us sleeping
1400 * so as not to count towards the load average)..
1402 set_current_state(TASK_INTERRUPTIBLE);
1403 apm_event_handler();
1405 remove_wait_queue(&apm_waitqueue, &wait);
1408 static int check_apm_user(struct apm_user *as, const char *func)
1410 if ((as == NULL) || (as->magic != APM_BIOS_MAGIC)) {
1411 printk(KERN_ERR "apm: %s passed bad filp\n", func);
1417 static ssize_t do_read(struct file *fp, char __user *buf, size_t count, loff_t *ppos)
1419 struct apm_user * as;
1423 as = fp->private_data;
1424 if (check_apm_user(as, "read"))
1426 if ((int)count < sizeof(apm_event_t))
1428 if ((queue_empty(as)) && (fp->f_flags & O_NONBLOCK))
1430 wait_event_interruptible(apm_waitqueue, !queue_empty(as));
1432 while ((i >= sizeof(event)) && !queue_empty(as)) {
1433 event = get_queued_event(as);
1434 if (copy_to_user(buf, &event, sizeof(event))) {
1440 case APM_SYS_SUSPEND:
1441 case APM_USER_SUSPEND:
1442 as->suspends_read++;
1445 case APM_SYS_STANDBY:
1446 case APM_USER_STANDBY:
1447 as->standbys_read++;
1450 buf += sizeof(event);
1455 if (signal_pending(current))
1456 return -ERESTARTSYS;
1460 static unsigned int do_poll(struct file *fp, poll_table * wait)
1462 struct apm_user * as;
1464 as = fp->private_data;
1465 if (check_apm_user(as, "poll"))
1467 poll_wait(fp, &apm_waitqueue, wait);
1468 if (!queue_empty(as))
1469 return POLLIN | POLLRDNORM;
1473 static int do_ioctl(struct inode * inode, struct file *filp,
1474 u_int cmd, u_long arg)
1476 struct apm_user * as;
1478 as = filp->private_data;
1479 if (check_apm_user(as, "ioctl"))
1481 if ((!as->suser) || (!as->writer))
1484 case APM_IOC_STANDBY:
1485 if (as->standbys_read > 0) {
1486 as->standbys_read--;
1487 as->standbys_pending--;
1490 queue_event(APM_USER_STANDBY, as);
1491 if (standbys_pending <= 0)
1494 case APM_IOC_SUSPEND:
1495 if (as->suspends_read > 0) {
1496 as->suspends_read--;
1497 as->suspends_pending--;
1500 queue_event(APM_USER_SUSPEND, as);
1501 if (suspends_pending <= 0) {
1504 as->suspend_wait = 1;
1505 wait_event_interruptible(apm_suspend_waitqueue,
1506 as->suspend_wait == 0);
1507 return as->suspend_result;
1516 static int do_release(struct inode * inode, struct file * filp)
1518 struct apm_user * as;
1520 as = filp->private_data;
1521 if (check_apm_user(as, "release"))
1523 filp->private_data = NULL;
1524 if (as->standbys_pending > 0) {
1525 standbys_pending -= as->standbys_pending;
1526 if (standbys_pending <= 0)
1529 if (as->suspends_pending > 0) {
1530 suspends_pending -= as->suspends_pending;
1531 if (suspends_pending <= 0)
1534 spin_lock(&user_list_lock);
1535 if (user_list == as)
1536 user_list = as->next;
1538 struct apm_user * as1;
1540 for (as1 = user_list;
1541 (as1 != NULL) && (as1->next != as);
1545 printk(KERN_ERR "apm: filp not in user list\n");
1547 as1->next = as->next;
1549 spin_unlock(&user_list_lock);
1554 static int do_open(struct inode * inode, struct file * filp)
1556 struct apm_user * as;
1558 as = kmalloc(sizeof(*as), GFP_KERNEL);
1560 printk(KERN_ERR "apm: cannot allocate struct of size %d bytes\n",
1564 as->magic = APM_BIOS_MAGIC;
1565 as->event_tail = as->event_head = 0;
1566 as->suspends_pending = as->standbys_pending = 0;
1567 as->suspends_read = as->standbys_read = 0;
1569 * XXX - this is a tiny bit broken, when we consider BSD
1570 * process accounting. If the device is opened by root, we
1571 * instantly flag that we used superuser privs. Who knows,
1572 * we might close the device immediately without doing a
1573 * privileged operation -- cevans
1575 as->suser = capable(CAP_SYS_ADMIN);
1576 as->writer = (filp->f_mode & FMODE_WRITE) == FMODE_WRITE;
1577 as->reader = (filp->f_mode & FMODE_READ) == FMODE_READ;
1578 spin_lock(&user_list_lock);
1579 as->next = user_list;
1581 spin_unlock(&user_list_lock);
1582 filp->private_data = as;
1586 static int proc_apm_show(struct seq_file *m, void *v)
1592 unsigned short ac_line_status = 0xff;
1593 unsigned short battery_status = 0xff;
1594 unsigned short battery_flag = 0xff;
1595 int percentage = -1;
1596 int time_units = -1;
1599 if ((num_online_cpus() == 1) &&
1600 !(error = apm_get_power_status(&bx, &cx, &dx))) {
1601 ac_line_status = (bx >> 8) & 0xff;
1602 battery_status = bx & 0xff;
1603 if ((cx & 0xff) != 0xff)
1604 percentage = cx & 0xff;
1606 if (apm_info.connection_version > 0x100) {
1607 battery_flag = (cx >> 8) & 0xff;
1609 units = (dx & 0x8000) ? "min" : "sec";
1610 time_units = dx & 0x7fff;
1614 /* Arguments, with symbols from linux/apm_bios.h. Information is
1615 from the Get Power Status (0x0a) call unless otherwise noted.
1617 0) Linux driver version (this will change if format changes)
1618 1) APM BIOS Version. Usually 1.0, 1.1 or 1.2.
1619 2) APM flags from APM Installation Check (0x00):
1620 bit 0: APM_16_BIT_SUPPORT
1621 bit 1: APM_32_BIT_SUPPORT
1622 bit 2: APM_IDLE_SLOWS_CLOCK
1623 bit 3: APM_BIOS_DISABLED
1624 bit 4: APM_BIOS_DISENGAGED
1628 0x02: On backup power (BIOS >= 1.1 only)
1635 0x04: Selected battery not present (BIOS >= 1.2 only)
1642 bit 7: No system battery
1644 6) Remaining battery life (percentage of charge):
1647 7) Remaining battery life (time units):
1648 Number of remaining minutes or seconds
1650 8) min = minutes; sec = seconds */
1652 seq_printf(m, "%s %d.%d 0x%02x 0x%02x 0x%02x 0x%02x %d%% %d %s\n",
1654 (apm_info.bios.version >> 8) & 0xff,
1655 apm_info.bios.version & 0xff,
1656 apm_info.bios.flags,
1666 static int proc_apm_open(struct inode *inode, struct file *file)
1668 return single_open(file, proc_apm_show, NULL);
1671 static const struct file_operations apm_file_ops = {
1672 .owner = THIS_MODULE,
1673 .open = proc_apm_open,
1675 .llseek = seq_lseek,
1676 .release = single_release,
1679 static int apm(void *unused)
1690 * This is to avoid random crashes at boot time during initialization
1691 * on SMP systems in case of "apm=power-off" mode. Seen on ASUS A7M266D.
1692 * Some bioses don't like being called from CPU != 0.
1693 * Method suggested by Ingo Molnar.
1695 set_cpus_allowed(current, cpumask_of_cpu(0));
1696 BUG_ON(smp_processor_id() != 0);
1699 if (apm_info.connection_version == 0) {
1700 apm_info.connection_version = apm_info.bios.version;
1701 if (apm_info.connection_version > 0x100) {
1703 * We only support BIOSs up to version 1.2
1705 if (apm_info.connection_version > 0x0102)
1706 apm_info.connection_version = 0x0102;
1707 error = apm_driver_version(&apm_info.connection_version);
1708 if (error != APM_SUCCESS) {
1709 apm_error("driver version", error);
1710 /* Fall back to an APM 1.0 connection. */
1711 apm_info.connection_version = 0x100;
1717 printk(KERN_INFO "apm: Connection version %d.%d\n",
1718 (apm_info.connection_version >> 8) & 0xff,
1719 apm_info.connection_version & 0xff);
1721 #ifdef CONFIG_APM_DO_ENABLE
1722 if (apm_info.bios.flags & APM_BIOS_DISABLED) {
1724 * This call causes my NEC UltraLite Versa 33/C to hang if it
1725 * is booted with PM disabled but not in the docking station.
1728 error = apm_enable_power_management(1);
1730 apm_error("enable power management", error);
1736 if ((apm_info.bios.flags & APM_BIOS_DISENGAGED)
1737 && (apm_info.connection_version > 0x0100)) {
1738 error = apm_engage_power_management(APM_DEVICE_ALL, 1);
1740 apm_error("engage power management", error);
1745 if (debug && (num_online_cpus() == 1 || smp )) {
1746 error = apm_get_power_status(&bx, &cx, &dx);
1748 printk(KERN_INFO "apm: power status not available\n");
1750 switch ((bx >> 8) & 0xff) {
1751 case 0: power_stat = "off line"; break;
1752 case 1: power_stat = "on line"; break;
1753 case 2: power_stat = "on backup power"; break;
1754 default: power_stat = "unknown"; break;
1756 switch (bx & 0xff) {
1757 case 0: bat_stat = "high"; break;
1758 case 1: bat_stat = "low"; break;
1759 case 2: bat_stat = "critical"; break;
1760 case 3: bat_stat = "charging"; break;
1761 default: bat_stat = "unknown"; break;
1764 "apm: AC %s, battery status %s, battery life ",
1765 power_stat, bat_stat);
1766 if ((cx & 0xff) == 0xff)
1767 printk("unknown\n");
1769 printk("%d%%\n", cx & 0xff);
1770 if (apm_info.connection_version > 0x100) {
1772 "apm: battery flag 0x%02x, battery life ",
1775 printk("unknown\n");
1777 printk("%d %s\n", dx & 0x7fff,
1779 "minutes" : "seconds");
1784 /* Install our power off handler.. */
1786 pm_power_off = apm_power_off;
1788 if (num_online_cpus() == 1 || smp) {
1789 #if defined(CONFIG_APM_DISPLAY_BLANK) && defined(CONFIG_VT)
1790 console_blank_hook = apm_console_blank;
1793 #if defined(CONFIG_APM_DISPLAY_BLANK) && defined(CONFIG_VT)
1794 console_blank_hook = NULL;
1802 static int __init apm_setup(char *str)
1806 while ((str != NULL) && (*str != '\0')) {
1807 if (strncmp(str, "off", 3) == 0)
1809 if (strncmp(str, "on", 2) == 0)
1811 if ((strncmp(str, "bounce-interval=", 16) == 0) ||
1812 (strncmp(str, "bounce_interval=", 16) == 0))
1813 bounce_interval = simple_strtol(str + 16, NULL, 0);
1814 if ((strncmp(str, "idle-threshold=", 15) == 0) ||
1815 (strncmp(str, "idle_threshold=", 15) == 0))
1816 idle_threshold = simple_strtol(str + 15, NULL, 0);
1817 if ((strncmp(str, "idle-period=", 12) == 0) ||
1818 (strncmp(str, "idle_period=", 12) == 0))
1819 idle_period = simple_strtol(str + 12, NULL, 0);
1820 invert = (strncmp(str, "no-", 3) == 0) ||
1821 (strncmp(str, "no_", 3) == 0);
1824 if (strncmp(str, "debug", 5) == 0)
1826 if ((strncmp(str, "power-off", 9) == 0) ||
1827 (strncmp(str, "power_off", 9) == 0))
1828 power_off = !invert;
1829 if (strncmp(str, "smp", 3) == 0)
1832 idle_threshold = 100;
1834 if ((strncmp(str, "allow-ints", 10) == 0) ||
1835 (strncmp(str, "allow_ints", 10) == 0))
1836 apm_info.allow_ints = !invert;
1837 if ((strncmp(str, "broken-psr", 10) == 0) ||
1838 (strncmp(str, "broken_psr", 10) == 0))
1839 apm_info.get_power_status_broken = !invert;
1840 if ((strncmp(str, "realmode-power-off", 18) == 0) ||
1841 (strncmp(str, "realmode_power_off", 18) == 0))
1842 apm_info.realmode_power_off = !invert;
1843 str = strchr(str, ',');
1845 str += strspn(str, ", \t");
1850 __setup("apm=", apm_setup);
1853 static const struct file_operations apm_bios_fops = {
1854 .owner = THIS_MODULE,
1859 .release = do_release,
1862 static struct miscdevice apm_device = {
1869 /* Simple "print if true" callback */
1870 static int __init print_if_true(const struct dmi_system_id *d)
1872 printk("%s\n", d->ident);
1877 * Some Bioses enable the PS/2 mouse (touchpad) at resume, even if it was
1878 * disabled before the suspend. Linux used to get terribly confused by that.
1880 static int __init broken_ps2_resume(const struct dmi_system_id *d)
1882 printk(KERN_INFO "%s machine detected. Mousepad Resume Bug workaround hopefully not needed.\n", d->ident);
1886 /* Some bioses have a broken protected mode poweroff and need to use realmode */
1887 static int __init set_realmode_power_off(const struct dmi_system_id *d)
1889 if (apm_info.realmode_power_off == 0) {
1890 apm_info.realmode_power_off = 1;
1891 printk(KERN_INFO "%s bios detected. Using realmode poweroff only.\n", d->ident);
1896 /* Some laptops require interrupts to be enabled during APM calls */
1897 static int __init set_apm_ints(const struct dmi_system_id *d)
1899 if (apm_info.allow_ints == 0) {
1900 apm_info.allow_ints = 1;
1901 printk(KERN_INFO "%s machine detected. Enabling interrupts during APM calls.\n", d->ident);
1906 /* Some APM bioses corrupt memory or just plain do not work */
1907 static int __init apm_is_horked(const struct dmi_system_id *d)
1909 if (apm_info.disabled == 0) {
1910 apm_info.disabled = 1;
1911 printk(KERN_INFO "%s machine detected. Disabling APM.\n", d->ident);
1916 static int __init apm_is_horked_d850md(const struct dmi_system_id *d)
1918 if (apm_info.disabled == 0) {
1919 apm_info.disabled = 1;
1920 printk(KERN_INFO "%s machine detected. Disabling APM.\n", d->ident);
1921 printk(KERN_INFO "This bug is fixed in bios P15 which is available for \n");
1922 printk(KERN_INFO "download from support.intel.com \n");
1927 /* Some APM bioses hang on APM idle calls */
1928 static int __init apm_likes_to_melt(const struct dmi_system_id *d)
1930 if (apm_info.forbid_idle == 0) {
1931 apm_info.forbid_idle = 1;
1932 printk(KERN_INFO "%s machine detected. Disabling APM idle calls.\n", d->ident);
1938 * Check for clue free BIOS implementations who use
1939 * the following QA technique
1941 * [ Write BIOS Code ]<------
1943 * < Does it Compile >----N--
1945 * < Does it Boot Win98 >-N--
1949 * Phoenix A04 08/24/2000 is known bad (Dell Inspiron 5000e)
1950 * Phoenix A07 09/29/2000 is known good (Dell Inspiron 5000)
1952 static int __init broken_apm_power(const struct dmi_system_id *d)
1954 apm_info.get_power_status_broken = 1;
1955 printk(KERN_WARNING "BIOS strings suggest APM bugs, disabling power status reporting.\n");
1960 * This bios swaps the APM minute reporting bytes over (Many sony laptops
1961 * have this problem).
1963 static int __init swab_apm_power_in_minutes(const struct dmi_system_id *d)
1965 apm_info.get_power_status_swabinminutes = 1;
1966 printk(KERN_WARNING "BIOS strings suggest APM reports battery life in minutes and wrong byte order.\n");
1970 static struct dmi_system_id __initdata apm_dmi_table[] = {
1973 KERN_WARNING "IBM T23 - BIOS 1.03b+ and controller firmware 1.02+ may be needed for Linux APM.",
1974 { DMI_MATCH(DMI_SYS_VENDOR, "IBM"),
1975 DMI_MATCH(DMI_BIOS_VERSION, "1AET38WW (1.01b)"), },
1977 { /* Handle problems with APM on the C600 */
1978 broken_ps2_resume, "Dell Latitude C600",
1979 { DMI_MATCH(DMI_SYS_VENDOR, "Dell"),
1980 DMI_MATCH(DMI_PRODUCT_NAME, "Latitude C600"), },
1982 { /* Allow interrupts during suspend on Dell Latitude laptops*/
1983 set_apm_ints, "Dell Latitude",
1984 { DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
1985 DMI_MATCH(DMI_PRODUCT_NAME, "Latitude C510"), }
1988 apm_is_horked, "Dell Inspiron 2500",
1989 { DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
1990 DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 2500"),
1991 DMI_MATCH(DMI_BIOS_VENDOR,"Phoenix Technologies LTD"),
1992 DMI_MATCH(DMI_BIOS_VERSION,"A11"), },
1994 { /* Allow interrupts during suspend on Dell Inspiron laptops*/
1995 set_apm_ints, "Dell Inspiron", {
1996 DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
1997 DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 4000"), },
1999 { /* Handle problems with APM on Inspiron 5000e */
2000 broken_apm_power, "Dell Inspiron 5000e",
2001 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2002 DMI_MATCH(DMI_BIOS_VERSION, "A04"),
2003 DMI_MATCH(DMI_BIOS_DATE, "08/24/2000"), },
2005 { /* Handle problems with APM on Inspiron 2500 */
2006 broken_apm_power, "Dell Inspiron 2500",
2007 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2008 DMI_MATCH(DMI_BIOS_VERSION, "A12"),
2009 DMI_MATCH(DMI_BIOS_DATE, "02/04/2002"), },
2012 apm_is_horked, "Dell Dimension 4100",
2013 { DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
2014 DMI_MATCH(DMI_PRODUCT_NAME, "XPS-Z"),
2015 DMI_MATCH(DMI_BIOS_VENDOR,"Intel Corp."),
2016 DMI_MATCH(DMI_BIOS_VERSION,"A11"), },
2018 { /* Allow interrupts during suspend on Compaq Laptops*/
2019 set_apm_ints, "Compaq 12XL125",
2020 { DMI_MATCH(DMI_SYS_VENDOR, "Compaq"),
2021 DMI_MATCH(DMI_PRODUCT_NAME, "Compaq PC"),
2022 DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2023 DMI_MATCH(DMI_BIOS_VERSION,"4.06"), },
2025 { /* Allow interrupts during APM or the clock goes slow */
2026 set_apm_ints, "ASUSTeK",
2027 { DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK Computer Inc."),
2028 DMI_MATCH(DMI_PRODUCT_NAME, "L8400K series Notebook PC"), },
2030 { /* APM blows on shutdown */
2031 apm_is_horked, "ABIT KX7-333[R]",
2032 { DMI_MATCH(DMI_BOARD_VENDOR, "ABIT"),
2033 DMI_MATCH(DMI_BOARD_NAME, "VT8367-8233A (KX7-333[R])"), },
2036 apm_is_horked, "Trigem Delhi3",
2037 { DMI_MATCH(DMI_SYS_VENDOR, "TriGem Computer, Inc"),
2038 DMI_MATCH(DMI_PRODUCT_NAME, "Delhi3"), },
2041 apm_is_horked, "Fujitsu-Siemens",
2042 { DMI_MATCH(DMI_BIOS_VENDOR, "hoenix/FUJITSU SIEMENS"),
2043 DMI_MATCH(DMI_BIOS_VERSION, "Version1.01"), },
2046 apm_is_horked_d850md, "Intel D850MD",
2047 { DMI_MATCH(DMI_BIOS_VENDOR, "Intel Corp."),
2048 DMI_MATCH(DMI_BIOS_VERSION, "MV85010A.86A.0016.P07.0201251536"), },
2051 apm_is_horked, "Intel D810EMO",
2052 { DMI_MATCH(DMI_BIOS_VENDOR, "Intel Corp."),
2053 DMI_MATCH(DMI_BIOS_VERSION, "MO81010A.86A.0008.P04.0004170800"), },
2056 apm_is_horked, "Dell XPS-Z",
2057 { DMI_MATCH(DMI_BIOS_VENDOR, "Intel Corp."),
2058 DMI_MATCH(DMI_BIOS_VERSION, "A11"),
2059 DMI_MATCH(DMI_PRODUCT_NAME, "XPS-Z"), },
2062 apm_is_horked, "Sharp PC-PJ/AX",
2063 { DMI_MATCH(DMI_SYS_VENDOR, "SHARP"),
2064 DMI_MATCH(DMI_PRODUCT_NAME, "PC-PJ/AX"),
2065 DMI_MATCH(DMI_BIOS_VENDOR,"SystemSoft"),
2066 DMI_MATCH(DMI_BIOS_VERSION,"Version R2.08"), },
2069 apm_is_horked, "Dell Inspiron 2500",
2070 { DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
2071 DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 2500"),
2072 DMI_MATCH(DMI_BIOS_VENDOR,"Phoenix Technologies LTD"),
2073 DMI_MATCH(DMI_BIOS_VERSION,"A11"), },
2075 { /* APM idle hangs */
2076 apm_likes_to_melt, "Jabil AMD",
2077 { DMI_MATCH(DMI_BIOS_VENDOR, "American Megatrends Inc."),
2078 DMI_MATCH(DMI_BIOS_VERSION, "0AASNP06"), },
2080 { /* APM idle hangs */
2081 apm_likes_to_melt, "AMI Bios",
2082 { DMI_MATCH(DMI_BIOS_VENDOR, "American Megatrends Inc."),
2083 DMI_MATCH(DMI_BIOS_VERSION, "0AASNP05"), },
2085 { /* Handle problems with APM on Sony Vaio PCG-N505X(DE) */
2086 swab_apm_power_in_minutes, "Sony VAIO",
2087 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2088 DMI_MATCH(DMI_BIOS_VERSION, "R0206H"),
2089 DMI_MATCH(DMI_BIOS_DATE, "08/23/99"), },
2091 { /* Handle problems with APM on Sony Vaio PCG-N505VX */
2092 swab_apm_power_in_minutes, "Sony VAIO",
2093 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2094 DMI_MATCH(DMI_BIOS_VERSION, "W2K06H0"),
2095 DMI_MATCH(DMI_BIOS_DATE, "02/03/00"), },
2097 { /* Handle problems with APM on Sony Vaio PCG-XG29 */
2098 swab_apm_power_in_minutes, "Sony VAIO",
2099 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2100 DMI_MATCH(DMI_BIOS_VERSION, "R0117A0"),
2101 DMI_MATCH(DMI_BIOS_DATE, "04/25/00"), },
2103 { /* Handle problems with APM on Sony Vaio PCG-Z600NE */
2104 swab_apm_power_in_minutes, "Sony VAIO",
2105 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2106 DMI_MATCH(DMI_BIOS_VERSION, "R0121Z1"),
2107 DMI_MATCH(DMI_BIOS_DATE, "05/11/00"), },
2109 { /* Handle problems with APM on Sony Vaio PCG-Z600NE */
2110 swab_apm_power_in_minutes, "Sony VAIO",
2111 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2112 DMI_MATCH(DMI_BIOS_VERSION, "WME01Z1"),
2113 DMI_MATCH(DMI_BIOS_DATE, "08/11/00"), },
2115 { /* Handle problems with APM on Sony Vaio PCG-Z600LEK(DE) */
2116 swab_apm_power_in_minutes, "Sony VAIO",
2117 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2118 DMI_MATCH(DMI_BIOS_VERSION, "R0206Z3"),
2119 DMI_MATCH(DMI_BIOS_DATE, "12/25/00"), },
2121 { /* Handle problems with APM on Sony Vaio PCG-Z505LS */
2122 swab_apm_power_in_minutes, "Sony VAIO",
2123 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2124 DMI_MATCH(DMI_BIOS_VERSION, "R0203D0"),
2125 DMI_MATCH(DMI_BIOS_DATE, "05/12/00"), },
2127 { /* Handle problems with APM on Sony Vaio PCG-Z505LS */
2128 swab_apm_power_in_minutes, "Sony VAIO",
2129 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2130 DMI_MATCH(DMI_BIOS_VERSION, "R0203Z3"),
2131 DMI_MATCH(DMI_BIOS_DATE, "08/25/00"), },
2133 { /* Handle problems with APM on Sony Vaio PCG-Z505LS (with updated BIOS) */
2134 swab_apm_power_in_minutes, "Sony VAIO",
2135 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2136 DMI_MATCH(DMI_BIOS_VERSION, "R0209Z3"),
2137 DMI_MATCH(DMI_BIOS_DATE, "05/12/01"), },
2139 { /* Handle problems with APM on Sony Vaio PCG-F104K */
2140 swab_apm_power_in_minutes, "Sony VAIO",
2141 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2142 DMI_MATCH(DMI_BIOS_VERSION, "R0204K2"),
2143 DMI_MATCH(DMI_BIOS_DATE, "08/28/00"), },
2146 { /* Handle problems with APM on Sony Vaio PCG-C1VN/C1VE */
2147 swab_apm_power_in_minutes, "Sony VAIO",
2148 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2149 DMI_MATCH(DMI_BIOS_VERSION, "R0208P1"),
2150 DMI_MATCH(DMI_BIOS_DATE, "11/09/00"), },
2152 { /* Handle problems with APM on Sony Vaio PCG-C1VE */
2153 swab_apm_power_in_minutes, "Sony VAIO",
2154 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2155 DMI_MATCH(DMI_BIOS_VERSION, "R0204P1"),
2156 DMI_MATCH(DMI_BIOS_DATE, "09/12/00"), },
2158 { /* Handle problems with APM on Sony Vaio PCG-C1VE */
2159 swab_apm_power_in_minutes, "Sony VAIO",
2160 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2161 DMI_MATCH(DMI_BIOS_VERSION, "WXPO1Z3"),
2162 DMI_MATCH(DMI_BIOS_DATE, "10/26/01"), },
2164 { /* broken PM poweroff bios */
2165 set_realmode_power_off, "Award Software v4.60 PGMA",
2166 { DMI_MATCH(DMI_BIOS_VENDOR, "Award Software International, Inc."),
2167 DMI_MATCH(DMI_BIOS_VERSION, "4.60 PGMA"),
2168 DMI_MATCH(DMI_BIOS_DATE, "134526184"), },
2171 /* Generic per vendor APM settings */
2173 { /* Allow interrupts during suspend on IBM laptops */
2174 set_apm_ints, "IBM",
2175 { DMI_MATCH(DMI_SYS_VENDOR, "IBM"), },
2182 * Just start the APM thread. We do NOT want to do APM BIOS
2183 * calls from anything but the APM thread, if for no other reason
2184 * than the fact that we don't trust the APM BIOS. This way,
2185 * most common APM BIOS problems that lead to protection errors
2186 * etc will have at least some level of being contained...
2188 * In short, if something bad happens, at least we have a choice
2189 * of just killing the apm thread..
2191 static int __init apm_init(void)
2193 struct proc_dir_entry *apm_proc;
2194 struct desc_struct *gdt;
2197 dmi_check_system(apm_dmi_table);
2199 if (apm_info.bios.version == 0 || paravirt_enabled()) {
2200 printk(KERN_INFO "apm: BIOS not found.\n");
2204 "apm: BIOS version %d.%d Flags 0x%02x (Driver version %s)\n",
2205 ((apm_info.bios.version >> 8) & 0xff),
2206 (apm_info.bios.version & 0xff),
2207 apm_info.bios.flags,
2209 if ((apm_info.bios.flags & APM_32_BIT_SUPPORT) == 0) {
2210 printk(KERN_INFO "apm: no 32 bit BIOS support\n");
2215 apm_info.allow_ints = 1;
2217 apm_info.get_power_status_broken = 1;
2218 if (realmode_power_off)
2219 apm_info.realmode_power_off = 1;
2220 /* User can override, but default is to trust DMI */
2221 if (apm_disabled != -1)
2222 apm_info.disabled = apm_disabled;
2225 * Fix for the Compaq Contura 3/25c which reports BIOS version 0.1
2226 * but is reportedly a 1.0 BIOS.
2228 if (apm_info.bios.version == 0x001)
2229 apm_info.bios.version = 0x100;
2231 /* BIOS < 1.2 doesn't set cseg_16_len */
2232 if (apm_info.bios.version < 0x102)
2233 apm_info.bios.cseg_16_len = 0; /* 64k */
2236 printk(KERN_INFO "apm: entry %x:%x cseg16 %x dseg %x",
2237 apm_info.bios.cseg, apm_info.bios.offset,
2238 apm_info.bios.cseg_16, apm_info.bios.dseg);
2239 if (apm_info.bios.version > 0x100)
2240 printk(" cseg len %x, dseg len %x",
2241 apm_info.bios.cseg_len,
2242 apm_info.bios.dseg_len);
2243 if (apm_info.bios.version > 0x101)
2244 printk(" cseg16 len %x", apm_info.bios.cseg_16_len);
2248 if (apm_info.disabled) {
2249 printk(KERN_NOTICE "apm: disabled on user request.\n");
2252 if ((num_online_cpus() > 1) && !power_off && !smp) {
2253 printk(KERN_NOTICE "apm: disabled - APM is not SMP safe.\n");
2254 apm_info.disabled = 1;
2257 if (pm_flags & PM_ACPI) {
2258 printk(KERN_NOTICE "apm: overridden by ACPI.\n");
2259 apm_info.disabled = 1;
2265 * Set up a segment that references the real mode segment 0x40
2266 * that extends up to the end of page zero (that we have reserved).
2267 * This is for buggy BIOS's that refer to (real mode) segment 0x40
2268 * even though they are called in protected mode.
2270 set_base(bad_bios_desc, __va((unsigned long)0x40 << 4));
2271 _set_limit((char *)&bad_bios_desc, 4095 - (0x40 << 4));
2274 * Set up the long jump entry point to the APM BIOS, which is called
2275 * from inline assembly.
2277 apm_bios_entry.offset = apm_info.bios.offset;
2278 apm_bios_entry.segment = APM_CS;
2281 * The APM 1.1 BIOS is supposed to provide limit information that it
2282 * recognizes. Many machines do this correctly, but many others do
2283 * not restrict themselves to their claimed limit. When this happens,
2284 * they will cause a segmentation violation in the kernel at boot time.
2285 * Most BIOS's, however, will respect a 64k limit, so we use that.
2287 * Note we only set APM segments on CPU zero, since we pin the APM
2290 gdt = get_cpu_gdt_table(0);
2291 set_base(gdt[APM_CS >> 3],
2292 __va((unsigned long)apm_info.bios.cseg << 4));
2293 set_base(gdt[APM_CS_16 >> 3],
2294 __va((unsigned long)apm_info.bios.cseg_16 << 4));
2295 set_base(gdt[APM_DS >> 3],
2296 __va((unsigned long)apm_info.bios.dseg << 4));
2298 apm_proc = create_proc_entry("apm", 0, NULL);
2300 apm_proc->proc_fops = &apm_file_ops;
2302 kapmd_task = kthread_create(apm, NULL, "kapmd");
2303 if (IS_ERR(kapmd_task)) {
2304 printk(KERN_ERR "apm: disabled - Unable to start kernel "
2306 err = PTR_ERR(kapmd_task);
2308 remove_proc_entry("apm", NULL);
2311 wake_up_process(kapmd_task);
2313 if (num_online_cpus() > 1 && !smp ) {
2315 "apm: disabled - APM is not SMP safe (power off active).\n");
2320 * Note we don't actually care if the misc_device cannot be registered.
2321 * this driver can do its job without it, even if userspace can't
2322 * control it. just log the error
2324 if (misc_register(&apm_device))
2325 printk(KERN_WARNING "apm: Could not register misc device.\n");
2328 idle_period = (idle_period * HZ) / 100;
2329 if (idle_threshold < 100) {
2330 original_pm_idle = pm_idle;
2331 pm_idle = apm_cpu_idle;
2338 static void __exit apm_exit(void)
2343 pm_idle = original_pm_idle;
2345 * We are about to unload the current idle thread pm callback
2346 * (pm_idle), Wait for all processors to update cached/local
2347 * copies of pm_idle before proceeding.
2351 if (((apm_info.bios.flags & APM_BIOS_DISENGAGED) == 0)
2352 && (apm_info.connection_version > 0x0100)) {
2353 error = apm_engage_power_management(APM_DEVICE_ALL, 0);
2355 apm_error("disengage power management", error);
2357 misc_deregister(&apm_device);
2358 remove_proc_entry("apm", NULL);
2360 pm_power_off = NULL;
2362 kthread_stop(kapmd_task);
2365 pm_flags &= ~PM_APM;
2368 module_init(apm_init);
2369 module_exit(apm_exit);
2371 MODULE_AUTHOR("Stephen Rothwell");
2372 MODULE_DESCRIPTION("Advanced Power Management");
2373 MODULE_LICENSE("GPL");
2374 module_param(debug, bool, 0644);
2375 MODULE_PARM_DESC(debug, "Enable debug mode");
2376 module_param(power_off, bool, 0444);
2377 MODULE_PARM_DESC(power_off, "Enable power off");
2378 module_param(bounce_interval, int, 0444);
2379 MODULE_PARM_DESC(bounce_interval,
2380 "Set the number of ticks to ignore suspend bounces");
2381 module_param(allow_ints, bool, 0444);
2382 MODULE_PARM_DESC(allow_ints, "Allow interrupts during BIOS calls");
2383 module_param(broken_psr, bool, 0444);
2384 MODULE_PARM_DESC(broken_psr, "BIOS has a broken GetPowerStatus call");
2385 module_param(realmode_power_off, bool, 0444);
2386 MODULE_PARM_DESC(realmode_power_off,
2387 "Switch to real mode before powering off");
2388 module_param(idle_threshold, int, 0444);
2389 MODULE_PARM_DESC(idle_threshold,
2390 "System idle percentage above which to make APM BIOS idle calls");
2391 module_param(idle_period, int, 0444);
2392 MODULE_PARM_DESC(idle_period,
2393 "Period (in sec/100) over which to caculate the idle percentage");
2394 module_param(smp, bool, 0444);
2395 MODULE_PARM_DESC(smp,
2396 "Set this to enable APM use on an SMP platform. Use with caution on older systems");
2397 MODULE_ALIAS_MISCDEV(APM_MINOR_DEV);