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/smp_lock.h>
208 #include <linux/types.h>
209 #include <linux/stddef.h>
210 #include <linux/timer.h>
211 #include <linux/fcntl.h>
212 #include <linux/slab.h>
213 #include <linux/stat.h>
214 #include <linux/proc_fs.h>
215 #include <linux/seq_file.h>
216 #include <linux/miscdevice.h>
217 #include <linux/apm_bios.h>
218 #include <linux/init.h>
219 #include <linux/time.h>
220 #include <linux/sched.h>
221 #include <linux/pm.h>
222 #include <linux/pm_legacy.h>
223 #include <linux/capability.h>
224 #include <linux/device.h>
225 #include <linux/kernel.h>
226 #include <linux/freezer.h>
227 #include <linux/smp.h>
228 #include <linux/dmi.h>
229 #include <linux/suspend.h>
230 #include <linux/kthread.h>
231 #include <linux/jiffies.h>
232 #include <linux/smp_lock.h>
234 #include <asm/system.h>
235 #include <asm/uaccess.h>
236 #include <asm/desc.h>
237 #include <asm/i8253.h>
238 #include <asm/paravirt.h>
239 #include <asm/reboot.h>
241 #if defined(CONFIG_APM_DISPLAY_BLANK) && defined(CONFIG_VT)
242 extern int (*console_blank_hook
)(int);
246 * The apm_bios device is one of the misc char devices.
247 * This is its minor number.
249 #define APM_MINOR_DEV 134
252 * See Documentation/Config.help for the configuration options.
254 * Various options can be changed at boot time as follows:
255 * (We allow underscores for compatibility with the modules code)
256 * apm=on/off enable/disable APM
257 * [no-]allow[-_]ints allow interrupts during BIOS calls
258 * [no-]broken[-_]psr BIOS has a broken GetPowerStatus call
259 * [no-]realmode[-_]power[-_]off switch to real mode before
261 * [no-]debug log some debugging messages
262 * [no-]power[-_]off power off on shutdown
263 * [no-]smp Use apm even on an SMP box
264 * bounce[-_]interval=<n> number of ticks to ignore suspend
266 * idle[-_]threshold=<n> System idle percentage above which to
267 * make APM BIOS idle calls. Set it to
269 * idle[-_]period=<n> Period (in 1/100s of a second) over
270 * which the idle percentage is
274 /* KNOWN PROBLEM MACHINES:
276 * U: TI 4000M TravelMate: BIOS is *NOT* APM compliant
277 * [Confirmed by TI representative]
278 * ?: ACER 486DX4/75: uses dseg 0040, in violation of APM specification
279 * [Confirmed by BIOS disassembly]
280 * [This may work now ...]
281 * P: Toshiba 1950S: battery life information only gets updated after resume
282 * P: Midwest Micro Soundbook Elite DX2/66 monochrome: screen blanking
283 * broken in BIOS [Reported by Garst R. Reese <reese@isn.net>]
284 * ?: AcerNote-950: oops on reading /proc/apm - workaround is a WIP
285 * Neale Banks <neale@lowendale.com.au> December 2000
287 * Legend: U = unusable with APM patches
288 * P = partially usable with APM patches
292 * Define as 1 to make the driver always call the APM BIOS busy
293 * routine even if the clock was not reported as slowed by the
294 * idle routine. Otherwise, define as 0.
296 #define ALWAYS_CALL_BUSY 1
299 * Define to make the APM BIOS calls zero all data segment registers (so
300 * that an incorrect BIOS implementation will cause a kernel panic if it
301 * tries to write to arbitrary memory).
303 #define APM_ZERO_SEGS
308 * Define to re-initialize the interrupt 0 timer to 100 Hz after a suspend.
309 * This patched by Chad Miller <cmiller@surfsouth.com>, original code by
310 * David Chen <chen@ctpa04.mit.edu>
312 #undef INIT_TIMER_AFTER_SUSPEND
314 #ifdef INIT_TIMER_AFTER_SUSPEND
315 #include <linux/timex.h>
317 #include <linux/delay.h>
321 * Need to poll the APM BIOS every second
323 #define APM_CHECK_TIMEOUT (HZ)
326 * Ignore suspend events for this amount of time after a resume
328 #define DEFAULT_BOUNCE_INTERVAL (3 * HZ)
331 * Maximum number of events stored
333 #define APM_MAX_EVENTS 20
336 * The per-file APM data
340 struct apm_user
*next
;
341 unsigned int suser
: 1;
342 unsigned int writer
: 1;
343 unsigned int reader
: 1;
344 unsigned int suspend_wait
: 1;
346 int suspends_pending
;
347 int standbys_pending
;
352 apm_event_t events
[APM_MAX_EVENTS
];
356 * The magic number in apm_user
358 #define APM_BIOS_MAGIC 0x4101
361 * idle percentage above which bios idle calls are done
363 #ifdef CONFIG_APM_CPU_IDLE
364 #define DEFAULT_IDLE_THRESHOLD 95
366 #define DEFAULT_IDLE_THRESHOLD 100
368 #define DEFAULT_IDLE_PERIOD (100 / 3)
374 unsigned long offset
;
375 unsigned short segment
;
377 static int clock_slowed
;
378 static int idle_threshold __read_mostly
= DEFAULT_IDLE_THRESHOLD
;
379 static int idle_period __read_mostly
= DEFAULT_IDLE_PERIOD
;
380 static int set_pm_idle
;
381 static int suspends_pending
;
382 static int standbys_pending
;
383 static int ignore_sys_suspend
;
384 static int ignore_normal_resume
;
385 static int bounce_interval __read_mostly
= DEFAULT_BOUNCE_INTERVAL
;
387 static int debug __read_mostly
;
388 static int smp __read_mostly
;
389 static int apm_disabled
= -1;
391 static int power_off
;
393 static int power_off
= 1;
395 #ifdef CONFIG_APM_REAL_MODE_POWER_OFF
396 static int realmode_power_off
= 1;
398 static int realmode_power_off
;
400 #ifdef CONFIG_APM_ALLOW_INTS
401 static int allow_ints
= 1;
403 static int allow_ints
;
405 static int broken_psr
;
407 static DECLARE_WAIT_QUEUE_HEAD(apm_waitqueue
);
408 static DECLARE_WAIT_QUEUE_HEAD(apm_suspend_waitqueue
);
409 static struct apm_user
*user_list
;
410 static DEFINE_SPINLOCK(user_list_lock
);
411 static const struct desc_struct bad_bios_desc
= { { { 0, 0x00409200 } } };
413 static const char driver_version
[] = "1.16ac"; /* no spaces */
415 static struct task_struct
*kapmd_task
;
418 * APM event names taken from the APM 1.2 specification. These are
419 * the message codes that the BIOS uses to tell us about events
421 static const char * const apm_event_name
[] = {
427 "power status change",
432 "system standby resume",
433 "capabilities change"
435 #define NR_APM_EVENT_NAME ARRAY_SIZE(apm_event_name)
437 typedef struct lookup_t
{
443 * The BIOS returns a set of standard error codes in AX when the
447 static const lookup_t error_table
[] = {
448 /* N/A { APM_SUCCESS, "Operation succeeded" }, */
449 { APM_DISABLED
, "Power management disabled" },
450 { APM_CONNECTED
, "Real mode interface already connected" },
451 { APM_NOT_CONNECTED
, "Interface not connected" },
452 { APM_16_CONNECTED
, "16 bit interface already connected" },
453 /* N/A { APM_16_UNSUPPORTED, "16 bit interface not supported" }, */
454 { APM_32_CONNECTED
, "32 bit interface already connected" },
455 { APM_32_UNSUPPORTED
, "32 bit interface not supported" },
456 { APM_BAD_DEVICE
, "Unrecognized device ID" },
457 { APM_BAD_PARAM
, "Parameter out of range" },
458 { APM_NOT_ENGAGED
, "Interface not engaged" },
459 { APM_BAD_FUNCTION
, "Function not supported" },
460 { APM_RESUME_DISABLED
, "Resume timer disabled" },
461 { APM_BAD_STATE
, "Unable to enter requested state" },
462 /* N/A { APM_NO_EVENTS, "No events pending" }, */
463 { APM_NO_ERROR
, "BIOS did not set a return code" },
464 { APM_NOT_PRESENT
, "No APM present" }
466 #define ERROR_COUNT ARRAY_SIZE(error_table)
469 * apm_error - display an APM error
470 * @str: information string
471 * @err: APM BIOS return code
473 * Write a meaningful log entry to the kernel log in the event of
477 static void apm_error(char *str
, int err
)
481 for (i
= 0; i
< ERROR_COUNT
; i
++)
482 if (error_table
[i
].key
== err
)
485 printk(KERN_NOTICE
"apm: %s: %s\n", str
, error_table
[i
].msg
);
487 printk(KERN_NOTICE
"apm: %s: unknown error code %#2.2x\n",
492 * Lock APM functionality to physical CPU 0
497 static cpumask_t
apm_save_cpus(void)
499 cpumask_t x
= current
->cpus_allowed
;
500 /* Some bioses don't like being called from CPU != 0 */
501 set_cpus_allowed(current
, cpumask_of_cpu(0));
502 BUG_ON(smp_processor_id() != 0);
506 static inline void apm_restore_cpus(cpumask_t mask
)
508 set_cpus_allowed(current
, mask
);
514 * No CPU lockdown needed on a uniprocessor
517 #define apm_save_cpus() (current->cpus_allowed)
518 #define apm_restore_cpus(x) (void)(x)
523 * These are the actual BIOS calls. Depending on APM_ZERO_SEGS and
524 * apm_info.allow_ints, we are being really paranoid here! Not only
525 * are interrupts disabled, but all the segment registers (except SS)
526 * are saved and zeroed this means that if the BIOS tries to reference
527 * any data without explicitly loading the segment registers, the kernel
528 * will fault immediately rather than have some unforeseen circumstances
529 * for the rest of the kernel. And it will be very obvious! :-) Doing
530 * this depends on CS referring to the same physical memory as DS so that
531 * DS can be zeroed before the call. Unfortunately, we can't do anything
532 * about the stack segment/pointer. Also, we tell the compiler that
533 * everything could change.
535 * Also, we KNOW that for the non error case of apm_bios_call, there
536 * is no useful data returned in the low order 8 bits of eax.
539 static inline unsigned long __apm_irq_save(void)
542 local_save_flags(flags
);
543 if (apm_info
.allow_ints
) {
544 if (irqs_disabled_flags(flags
))
552 #define apm_irq_save(flags) \
553 do { flags = __apm_irq_save(); } while (0)
555 static inline void apm_irq_restore(unsigned long flags
)
557 if (irqs_disabled_flags(flags
))
559 else if (irqs_disabled())
564 # define APM_DECL_SEGS \
565 unsigned int saved_fs; unsigned int saved_gs;
566 # define APM_DO_SAVE_SEGS \
567 savesegment(fs, saved_fs); savesegment(gs, saved_gs)
568 # define APM_DO_RESTORE_SEGS \
569 loadsegment(fs, saved_fs); loadsegment(gs, saved_gs)
571 # define APM_DECL_SEGS
572 # define APM_DO_SAVE_SEGS
573 # define APM_DO_RESTORE_SEGS
577 * apm_bios_call - Make an APM BIOS 32bit call
578 * @func: APM function to execute
579 * @ebx_in: EBX register for call entry
580 * @ecx_in: ECX register for call entry
581 * @eax: EAX register return
582 * @ebx: EBX register return
583 * @ecx: ECX register return
584 * @edx: EDX register return
585 * @esi: ESI register return
587 * Make an APM call using the 32bit protected mode interface. The
588 * caller is responsible for knowing if APM BIOS is configured and
589 * enabled. This call can disable interrupts for a long period of
590 * time on some laptops. The return value is in AH and the carry
591 * flag is loaded into AL. If there is an error, then the error
592 * code is returned in AH (bits 8-15 of eax) and this function
596 static u8
apm_bios_call(u32 func
, u32 ebx_in
, u32 ecx_in
,
597 u32
*eax
, u32
*ebx
, u32
*ecx
, u32
*edx
, u32
*esi
)
603 struct desc_struct save_desc_40
;
604 struct desc_struct
*gdt
;
606 cpus
= apm_save_cpus();
609 gdt
= get_cpu_gdt_table(cpu
);
610 save_desc_40
= gdt
[0x40 / 8];
611 gdt
[0x40 / 8] = bad_bios_desc
;
615 apm_bios_call_asm(func
, ebx_in
, ecx_in
, eax
, ebx
, ecx
, edx
, esi
);
617 apm_irq_restore(flags
);
618 gdt
[0x40 / 8] = save_desc_40
;
620 apm_restore_cpus(cpus
);
626 * apm_bios_call_simple - make a simple APM BIOS 32bit call
627 * @func: APM function to invoke
628 * @ebx_in: EBX register value for BIOS call
629 * @ecx_in: ECX register value for BIOS call
630 * @eax: EAX register on return from the BIOS call
632 * Make a BIOS call that returns one value only, or just status.
633 * If there is an error, then the error code is returned in AH
634 * (bits 8-15 of eax) and this function returns non-zero. This is
635 * used for simpler BIOS operations. This call may hold interrupts
636 * off for a long time on some laptops.
639 static u8
apm_bios_call_simple(u32 func
, u32 ebx_in
, u32 ecx_in
, u32
*eax
)
646 struct desc_struct save_desc_40
;
647 struct desc_struct
*gdt
;
649 cpus
= apm_save_cpus();
652 gdt
= get_cpu_gdt_table(cpu
);
653 save_desc_40
= gdt
[0x40 / 8];
654 gdt
[0x40 / 8] = bad_bios_desc
;
658 error
= apm_bios_call_simple_asm(func
, ebx_in
, ecx_in
, eax
);
660 apm_irq_restore(flags
);
661 gdt
[0x40 / 8] = save_desc_40
;
663 apm_restore_cpus(cpus
);
668 * apm_driver_version - APM driver version
669 * @val: loaded with the APM version on return
671 * Retrieve the APM version supported by the BIOS. This is only
672 * supported for APM 1.1 or higher. An error indicates APM 1.0 is
675 * On entry val should point to a value indicating the APM driver
676 * version with the high byte being the major and the low byte the
677 * minor number both in BCD
679 * On return it will hold the BIOS revision supported in the
683 static int apm_driver_version(u_short
*val
)
687 if (apm_bios_call_simple(APM_FUNC_VERSION
, 0, *val
, &eax
))
688 return (eax
>> 8) & 0xff;
694 * apm_get_event - get an APM event from the BIOS
695 * @event: pointer to the event
696 * @info: point to the event information
698 * The APM BIOS provides a polled information for event
699 * reporting. The BIOS expects to be polled at least every second
700 * when events are pending. When a message is found the caller should
701 * poll until no more messages are present. However, this causes
702 * problems on some laptops where a suspend event notification is
703 * not cleared until it is acknowledged.
705 * Additional information is returned in the info pointer, providing
706 * that APM 1.2 is in use. If no messges are pending the value 0x80
707 * is returned (No power management events pending).
710 static int apm_get_event(apm_event_t
*event
, apm_eventinfo_t
*info
)
717 if (apm_bios_call(APM_FUNC_GET_EVENT
, 0, 0, &eax
, &ebx
, &ecx
,
719 return (eax
>> 8) & 0xff;
721 if (apm_info
.connection_version
< 0x0102)
722 *info
= ~0; /* indicate info not valid */
729 * set_power_state - set the power management state
730 * @what: which items to transition
731 * @state: state to transition to
733 * Request an APM change of state for one or more system devices. The
734 * processor state must be transitioned last of all. what holds the
735 * class of device in the upper byte and the device number (0xFF for
736 * all) for the object to be transitioned.
738 * The state holds the state to transition to, which may in fact
739 * be an acceptance of a BIOS requested state change.
742 static int set_power_state(u_short what
, u_short state
)
746 if (apm_bios_call_simple(APM_FUNC_SET_STATE
, what
, state
, &eax
))
747 return (eax
>> 8) & 0xff;
752 * set_system_power_state - set system wide power state
753 * @state: which state to enter
755 * Transition the entire system into a new APM power state.
758 static int set_system_power_state(u_short state
)
760 return set_power_state(APM_DEVICE_ALL
, state
);
764 * apm_do_idle - perform power saving
766 * This function notifies the BIOS that the processor is (in the view
767 * of the OS) idle. It returns -1 in the event that the BIOS refuses
768 * to handle the idle request. On a success the function returns 1
769 * if the BIOS did clock slowing or 0 otherwise.
772 static int apm_do_idle(void)
779 polling
= !!(current_thread_info()->status
& TS_POLLING
);
781 current_thread_info()->status
&= ~TS_POLLING
;
783 * TS_POLLING-cleared state must be visible before we
788 if (!need_resched()) {
790 ret
= apm_bios_call_simple(APM_FUNC_IDLE
, 0, 0, &eax
);
793 current_thread_info()->status
|= TS_POLLING
;
799 static unsigned long t
;
801 /* This always fails on some SMP boards running UP kernels.
802 * Only report the failure the first 5 times.
805 printk(KERN_DEBUG
"apm_do_idle failed (%d)\n",
811 clock_slowed
= (apm_info
.bios
.flags
& APM_IDLE_SLOWS_CLOCK
) != 0;
816 * apm_do_busy - inform the BIOS the CPU is busy
818 * Request that the BIOS brings the CPU back to full performance.
821 static void apm_do_busy(void)
825 if (clock_slowed
|| ALWAYS_CALL_BUSY
) {
826 (void)apm_bios_call_simple(APM_FUNC_BUSY
, 0, 0, &dummy
);
832 * If no process has really been interested in
833 * the CPU for some time, we want to call BIOS
834 * power management - we probably want
837 #define IDLE_CALC_LIMIT (HZ * 100)
838 #define IDLE_LEAKY_MAX 16
840 static void (*original_pm_idle
)(void) __read_mostly
;
843 * apm_cpu_idle - cpu idling for APM capable Linux
845 * This is the idling function the kernel executes when APM is available. It
846 * tries to do BIOS powermanagement based on the average system idle time.
847 * Furthermore it calls the system default idle routine.
850 static void apm_cpu_idle(void)
852 static int use_apm_idle
; /* = 0 */
853 static unsigned int last_jiffies
; /* = 0 */
854 static unsigned int last_stime
; /* = 0 */
856 int apm_idle_done
= 0;
857 unsigned int jiffies_since_last_check
= jiffies
- last_jiffies
;
861 if (jiffies_since_last_check
> IDLE_CALC_LIMIT
) {
863 last_jiffies
= jiffies
;
864 last_stime
= current
->stime
;
865 } else if (jiffies_since_last_check
> idle_period
) {
866 unsigned int idle_percentage
;
868 idle_percentage
= current
->stime
- last_stime
;
869 idle_percentage
*= 100;
870 idle_percentage
/= jiffies_since_last_check
;
871 use_apm_idle
= (idle_percentage
> idle_threshold
);
872 if (apm_info
.forbid_idle
)
874 last_jiffies
= jiffies
;
875 last_stime
= current
->stime
;
878 bucket
= IDLE_LEAKY_MAX
;
880 while (!need_resched()) {
885 switch (apm_do_idle()) {
890 bucket
= IDLE_LEAKY_MAX
;
901 default: /* BIOS refused */
905 if (original_pm_idle
)
910 jiffies_since_last_check
= jiffies
- last_jiffies
;
911 if (jiffies_since_last_check
> idle_period
)
922 * apm_power_off - ask the BIOS to power off
924 * Handle the power off sequence. This is the one piece of code we
925 * will execute even on SMP machines. In order to deal with BIOS
926 * bugs we support real mode APM BIOS power off calls. We also make
927 * the SMP call on CPU0 as some systems will only honour this call
928 * on their first cpu.
931 static void apm_power_off(void)
933 unsigned char po_bios_call
[] = {
934 0xb8, 0x00, 0x10, /* movw $0x1000,ax */
935 0x8e, 0xd0, /* movw ax,ss */
936 0xbc, 0x00, 0xf0, /* movw $0xf000,sp */
937 0xb8, 0x07, 0x53, /* movw $0x5307,ax */
938 0xbb, 0x01, 0x00, /* movw $0x0001,bx */
939 0xb9, 0x03, 0x00, /* movw $0x0003,cx */
940 0xcd, 0x15 /* int $0x15 */
943 /* Some bioses don't like being called from CPU != 0 */
944 if (apm_info
.realmode_power_off
) {
945 (void)apm_save_cpus();
946 machine_real_restart(po_bios_call
, sizeof(po_bios_call
));
948 (void)set_system_power_state(APM_STATE_OFF
);
952 #ifdef CONFIG_APM_DO_ENABLE
955 * apm_enable_power_management - enable BIOS APM power management
956 * @enable: enable yes/no
958 * Enable or disable the APM BIOS power services.
961 static int apm_enable_power_management(int enable
)
965 if ((enable
== 0) && (apm_info
.bios
.flags
& APM_BIOS_DISENGAGED
))
966 return APM_NOT_ENGAGED
;
967 if (apm_bios_call_simple(APM_FUNC_ENABLE_PM
, APM_DEVICE_BALL
,
969 return (eax
>> 8) & 0xff;
971 apm_info
.bios
.flags
&= ~APM_BIOS_DISABLED
;
973 apm_info
.bios
.flags
|= APM_BIOS_DISABLED
;
979 * apm_get_power_status - get current power state
980 * @status: returned status
982 * @life: estimated life
984 * Obtain the current power status from the APM BIOS. We return a
985 * status which gives the rough battery status, and current power
986 * source. The bat value returned give an estimate as a percentage
987 * of life and a status value for the battery. The estimated life
988 * if reported is a lifetime in secodnds/minutes at current powwer
992 static int apm_get_power_status(u_short
*status
, u_short
*bat
, u_short
*life
)
1000 if (apm_info
.get_power_status_broken
)
1001 return APM_32_UNSUPPORTED
;
1002 if (apm_bios_call(APM_FUNC_GET_STATUS
, APM_DEVICE_ALL
, 0,
1003 &eax
, &ebx
, &ecx
, &edx
, &dummy
))
1004 return (eax
>> 8) & 0xff;
1007 if (apm_info
.get_power_status_swabinminutes
) {
1008 *life
= swab16((u16
)edx
);
1016 static int apm_get_battery_status(u_short which
, u_short
*status
,
1017 u_short
*bat
, u_short
*life
, u_short
*nbat
)
1025 if (apm_info
.connection_version
< 0x0102) {
1026 /* pretend we only have one battery. */
1028 return APM_BAD_DEVICE
;
1030 return apm_get_power_status(status
, bat
, life
);
1033 if (apm_bios_call(APM_FUNC_GET_STATUS
, (0x8000 | (which
)), 0, &eax
,
1034 &ebx
, &ecx
, &edx
, &esi
))
1035 return (eax
>> 8) & 0xff;
1045 * apm_engage_power_management - enable PM on a device
1046 * @device: identity of device
1049 * Activate or deactive power management on either a specific device
1050 * or the entire system (%APM_DEVICE_ALL).
1053 static int apm_engage_power_management(u_short device
, int enable
)
1057 if ((enable
== 0) && (device
== APM_DEVICE_ALL
)
1058 && (apm_info
.bios
.flags
& APM_BIOS_DISABLED
))
1059 return APM_DISABLED
;
1060 if (apm_bios_call_simple(APM_FUNC_ENGAGE_PM
, device
, enable
, &eax
))
1061 return (eax
>> 8) & 0xff;
1062 if (device
== APM_DEVICE_ALL
) {
1064 apm_info
.bios
.flags
&= ~APM_BIOS_DISENGAGED
;
1066 apm_info
.bios
.flags
|= APM_BIOS_DISENGAGED
;
1071 #if defined(CONFIG_APM_DISPLAY_BLANK) && defined(CONFIG_VT)
1074 * apm_console_blank - blank the display
1077 * Attempt to blank the console, firstly by blanking just video device
1078 * zero, and if that fails (some BIOSes don't support it) then it blanks
1079 * all video devices. Typically the BIOS will do laptop backlight and
1080 * monitor powerdown for us.
1083 static int apm_console_blank(int blank
)
1085 int error
= APM_NOT_ENGAGED
; /* silence gcc */
1088 static const u_short dev
[3] = { 0x100, 0x1FF, 0x101 };
1090 state
= blank
? APM_STATE_STANDBY
: APM_STATE_READY
;
1092 for (i
= 0; i
< ARRAY_SIZE(dev
); i
++) {
1093 error
= set_power_state(dev
[i
], state
);
1095 if ((error
== APM_SUCCESS
) || (error
== APM_NO_ERROR
))
1098 if (error
== APM_NOT_ENGAGED
)
1102 if (error
== APM_NOT_ENGAGED
) {
1106 eng_error
= apm_engage_power_management(APM_DEVICE_ALL
, 1);
1108 apm_error("set display", error
);
1109 apm_error("engage interface", eng_error
);
1112 return apm_console_blank(blank
);
1115 apm_error("set display", error
);
1120 static int queue_empty(struct apm_user
*as
)
1122 return as
->event_head
== as
->event_tail
;
1125 static apm_event_t
get_queued_event(struct apm_user
*as
)
1127 if (++as
->event_tail
>= APM_MAX_EVENTS
)
1129 return as
->events
[as
->event_tail
];
1132 static void queue_event(apm_event_t event
, struct apm_user
*sender
)
1134 struct apm_user
*as
;
1136 spin_lock(&user_list_lock
);
1137 if (user_list
== NULL
)
1139 for (as
= user_list
; as
!= NULL
; as
= as
->next
) {
1140 if ((as
== sender
) || (!as
->reader
))
1142 if (++as
->event_head
>= APM_MAX_EVENTS
)
1145 if (as
->event_head
== as
->event_tail
) {
1146 static int notified
;
1148 if (notified
++ == 0)
1149 printk(KERN_ERR
"apm: an event queue overflowed\n");
1150 if (++as
->event_tail
>= APM_MAX_EVENTS
)
1153 as
->events
[as
->event_head
] = event
;
1154 if (!as
->suser
|| !as
->writer
)
1157 case APM_SYS_SUSPEND
:
1158 case APM_USER_SUSPEND
:
1159 as
->suspends_pending
++;
1163 case APM_SYS_STANDBY
:
1164 case APM_USER_STANDBY
:
1165 as
->standbys_pending
++;
1170 wake_up_interruptible(&apm_waitqueue
);
1172 spin_unlock(&user_list_lock
);
1175 static void reinit_timer(void)
1177 #ifdef INIT_TIMER_AFTER_SUSPEND
1178 unsigned long flags
;
1180 spin_lock_irqsave(&i8253_lock
, flags
);
1181 /* set the clock to HZ */
1182 outb_pit(0x34, PIT_MODE
); /* binary, mode 2, LSB/MSB, ch 0 */
1184 outb_pit(LATCH
& 0xff, PIT_CH0
); /* LSB */
1186 outb_pit(LATCH
>> 8, PIT_CH0
); /* MSB */
1188 spin_unlock_irqrestore(&i8253_lock
, flags
);
1192 static int suspend(int vetoable
)
1195 struct apm_user
*as
;
1197 device_suspend(PMSG_SUSPEND
);
1198 local_irq_disable();
1199 device_power_down(PMSG_SUSPEND
);
1203 save_processor_state();
1204 err
= set_system_power_state(APM_STATE_SUSPEND
);
1205 ignore_normal_resume
= 1;
1206 restore_processor_state();
1208 local_irq_disable();
1211 if (err
== APM_NO_ERROR
)
1213 if (err
!= APM_SUCCESS
)
1214 apm_error("suspend", err
);
1215 err
= (err
== APM_SUCCESS
) ? 0 : -EIO
;
1219 queue_event(APM_NORMAL_RESUME
, NULL
);
1220 spin_lock(&user_list_lock
);
1221 for (as
= user_list
; as
!= NULL
; as
= as
->next
) {
1222 as
->suspend_wait
= 0;
1223 as
->suspend_result
= err
;
1225 spin_unlock(&user_list_lock
);
1226 wake_up_interruptible(&apm_suspend_waitqueue
);
1230 static void standby(void)
1234 local_irq_disable();
1235 device_power_down(PMSG_SUSPEND
);
1238 err
= set_system_power_state(APM_STATE_STANDBY
);
1239 if ((err
!= APM_SUCCESS
) && (err
!= APM_NO_ERROR
))
1240 apm_error("standby", err
);
1242 local_irq_disable();
1247 static apm_event_t
get_event(void)
1250 apm_event_t event
= APM_NO_EVENTS
; /* silence gcc */
1251 apm_eventinfo_t info
;
1253 static int notified
;
1255 /* we don't use the eventinfo */
1256 error
= apm_get_event(&event
, &info
);
1257 if (error
== APM_SUCCESS
)
1260 if ((error
!= APM_NO_EVENTS
) && (notified
++ == 0))
1261 apm_error("get_event", error
);
1266 static void check_events(void)
1269 static unsigned long last_resume
;
1270 static int ignore_bounce
;
1272 while ((event
= get_event()) != 0) {
1274 if (event
<= NR_APM_EVENT_NAME
)
1275 printk(KERN_DEBUG
"apm: received %s notify\n",
1276 apm_event_name
[event
- 1]);
1278 printk(KERN_DEBUG
"apm: received unknown "
1279 "event 0x%02x\n", event
);
1282 && (time_after(jiffies
, last_resume
+ bounce_interval
)))
1286 case APM_SYS_STANDBY
:
1287 case APM_USER_STANDBY
:
1288 queue_event(event
, NULL
);
1289 if (standbys_pending
<= 0)
1293 case APM_USER_SUSPEND
:
1294 #ifdef CONFIG_APM_IGNORE_USER_SUSPEND
1295 if (apm_info
.connection_version
> 0x100)
1296 set_system_power_state(APM_STATE_REJECT
);
1299 case APM_SYS_SUSPEND
:
1300 if (ignore_bounce
) {
1301 if (apm_info
.connection_version
> 0x100)
1302 set_system_power_state(APM_STATE_REJECT
);
1306 * If we are already processing a SUSPEND,
1307 * then further SUSPEND events from the BIOS
1308 * will be ignored. We also return here to
1309 * cope with the fact that the Thinkpads keep
1310 * sending a SUSPEND event until something else
1313 if (ignore_sys_suspend
)
1315 ignore_sys_suspend
= 1;
1316 queue_event(event
, NULL
);
1317 if (suspends_pending
<= 0)
1321 case APM_NORMAL_RESUME
:
1322 case APM_CRITICAL_RESUME
:
1323 case APM_STANDBY_RESUME
:
1324 ignore_sys_suspend
= 0;
1325 last_resume
= jiffies
;
1327 if ((event
!= APM_NORMAL_RESUME
)
1328 || (ignore_normal_resume
== 0)) {
1330 queue_event(event
, NULL
);
1332 ignore_normal_resume
= 0;
1335 case APM_CAPABILITY_CHANGE
:
1336 case APM_LOW_BATTERY
:
1337 case APM_POWER_STATUS_CHANGE
:
1338 queue_event(event
, NULL
);
1339 /* If needed, notify drivers here */
1342 case APM_UPDATE_TIME
:
1345 case APM_CRITICAL_SUSPEND
:
1347 * We are not allowed to reject a critical suspend.
1355 static void apm_event_handler(void)
1357 static int pending_count
= 4;
1360 if ((standbys_pending
> 0) || (suspends_pending
> 0)) {
1361 if ((apm_info
.connection_version
> 0x100) &&
1362 (pending_count
-- <= 0)) {
1365 printk(KERN_DEBUG
"apm: setting state busy\n");
1366 err
= set_system_power_state(APM_STATE_BUSY
);
1368 apm_error("busy", err
);
1376 * This is the APM thread main loop.
1379 static void apm_mainloop(void)
1381 DECLARE_WAITQUEUE(wait
, current
);
1383 add_wait_queue(&apm_waitqueue
, &wait
);
1384 set_current_state(TASK_INTERRUPTIBLE
);
1386 schedule_timeout(APM_CHECK_TIMEOUT
);
1387 if (kthread_should_stop())
1390 * Ok, check all events, check for idle (and mark us sleeping
1391 * so as not to count towards the load average)..
1393 set_current_state(TASK_INTERRUPTIBLE
);
1394 apm_event_handler();
1396 remove_wait_queue(&apm_waitqueue
, &wait
);
1399 static int check_apm_user(struct apm_user
*as
, const char *func
)
1401 if (as
== NULL
|| as
->magic
!= APM_BIOS_MAGIC
) {
1402 printk(KERN_ERR
"apm: %s passed bad filp\n", func
);
1408 static ssize_t
do_read(struct file
*fp
, char __user
*buf
, size_t count
, loff_t
*ppos
)
1410 struct apm_user
*as
;
1414 as
= fp
->private_data
;
1415 if (check_apm_user(as
, "read"))
1417 if ((int)count
< sizeof(apm_event_t
))
1419 if ((queue_empty(as
)) && (fp
->f_flags
& O_NONBLOCK
))
1421 wait_event_interruptible(apm_waitqueue
, !queue_empty(as
));
1423 while ((i
>= sizeof(event
)) && !queue_empty(as
)) {
1424 event
= get_queued_event(as
);
1425 if (copy_to_user(buf
, &event
, sizeof(event
))) {
1431 case APM_SYS_SUSPEND
:
1432 case APM_USER_SUSPEND
:
1433 as
->suspends_read
++;
1436 case APM_SYS_STANDBY
:
1437 case APM_USER_STANDBY
:
1438 as
->standbys_read
++;
1441 buf
+= sizeof(event
);
1446 if (signal_pending(current
))
1447 return -ERESTARTSYS
;
1451 static unsigned int do_poll(struct file
*fp
, poll_table
*wait
)
1453 struct apm_user
*as
;
1455 as
= fp
->private_data
;
1456 if (check_apm_user(as
, "poll"))
1458 poll_wait(fp
, &apm_waitqueue
, wait
);
1459 if (!queue_empty(as
))
1460 return POLLIN
| POLLRDNORM
;
1464 static long do_ioctl(struct file
*filp
, u_int cmd
, u_long arg
)
1466 struct apm_user
*as
;
1469 as
= filp
->private_data
;
1470 if (check_apm_user(as
, "ioctl"))
1472 if (!as
->suser
|| !as
->writer
)
1475 case APM_IOC_STANDBY
:
1477 if (as
->standbys_read
> 0) {
1478 as
->standbys_read
--;
1479 as
->standbys_pending
--;
1482 queue_event(APM_USER_STANDBY
, as
);
1483 if (standbys_pending
<= 0)
1487 case APM_IOC_SUSPEND
:
1489 if (as
->suspends_read
> 0) {
1490 as
->suspends_read
--;
1491 as
->suspends_pending
--;
1494 queue_event(APM_USER_SUSPEND
, as
);
1495 if (suspends_pending
<= 0) {
1498 as
->suspend_wait
= 1;
1499 wait_event_interruptible(apm_suspend_waitqueue
,
1500 as
->suspend_wait
== 0);
1501 ret
= as
->suspend_result
;
1511 static int do_release(struct inode
*inode
, struct file
*filp
)
1513 struct apm_user
*as
;
1515 as
= filp
->private_data
;
1516 if (check_apm_user(as
, "release"))
1518 filp
->private_data
= NULL
;
1519 if (as
->standbys_pending
> 0) {
1520 standbys_pending
-= as
->standbys_pending
;
1521 if (standbys_pending
<= 0)
1524 if (as
->suspends_pending
> 0) {
1525 suspends_pending
-= as
->suspends_pending
;
1526 if (suspends_pending
<= 0)
1529 spin_lock(&user_list_lock
);
1530 if (user_list
== as
)
1531 user_list
= as
->next
;
1533 struct apm_user
*as1
;
1535 for (as1
= user_list
;
1536 (as1
!= NULL
) && (as1
->next
!= as
);
1540 printk(KERN_ERR
"apm: filp not in user list\n");
1542 as1
->next
= as
->next
;
1544 spin_unlock(&user_list_lock
);
1549 static int do_open(struct inode
*inode
, struct file
*filp
)
1551 struct apm_user
*as
;
1554 as
= kmalloc(sizeof(*as
), GFP_KERNEL
);
1556 printk(KERN_ERR
"apm: cannot allocate struct of size %d bytes\n",
1561 as
->magic
= APM_BIOS_MAGIC
;
1562 as
->event_tail
= as
->event_head
= 0;
1563 as
->suspends_pending
= as
->standbys_pending
= 0;
1564 as
->suspends_read
= as
->standbys_read
= 0;
1566 * XXX - this is a tiny bit broken, when we consider BSD
1567 * process accounting. If the device is opened by root, we
1568 * instantly flag that we used superuser privs. Who knows,
1569 * we might close the device immediately without doing a
1570 * privileged operation -- cevans
1572 as
->suser
= capable(CAP_SYS_ADMIN
);
1573 as
->writer
= (filp
->f_mode
& FMODE_WRITE
) == FMODE_WRITE
;
1574 as
->reader
= (filp
->f_mode
& FMODE_READ
) == FMODE_READ
;
1575 spin_lock(&user_list_lock
);
1576 as
->next
= user_list
;
1578 spin_unlock(&user_list_lock
);
1579 filp
->private_data
= as
;
1584 static int proc_apm_show(struct seq_file
*m
, void *v
)
1590 unsigned short ac_line_status
= 0xff;
1591 unsigned short battery_status
= 0xff;
1592 unsigned short battery_flag
= 0xff;
1593 int percentage
= -1;
1594 int time_units
= -1;
1597 if ((num_online_cpus() == 1) &&
1598 !(error
= apm_get_power_status(&bx
, &cx
, &dx
))) {
1599 ac_line_status
= (bx
>> 8) & 0xff;
1600 battery_status
= bx
& 0xff;
1601 if ((cx
& 0xff) != 0xff)
1602 percentage
= cx
& 0xff;
1604 if (apm_info
.connection_version
> 0x100) {
1605 battery_flag
= (cx
>> 8) & 0xff;
1607 units
= (dx
& 0x8000) ? "min" : "sec";
1608 time_units
= dx
& 0x7fff;
1612 /* Arguments, with symbols from linux/apm_bios.h. Information is
1613 from the Get Power Status (0x0a) call unless otherwise noted.
1615 0) Linux driver version (this will change if format changes)
1616 1) APM BIOS Version. Usually 1.0, 1.1 or 1.2.
1617 2) APM flags from APM Installation Check (0x00):
1618 bit 0: APM_16_BIT_SUPPORT
1619 bit 1: APM_32_BIT_SUPPORT
1620 bit 2: APM_IDLE_SLOWS_CLOCK
1621 bit 3: APM_BIOS_DISABLED
1622 bit 4: APM_BIOS_DISENGAGED
1626 0x02: On backup power (BIOS >= 1.1 only)
1633 0x04: Selected battery not present (BIOS >= 1.2 only)
1640 bit 7: No system battery
1642 6) Remaining battery life (percentage of charge):
1645 7) Remaining battery life (time units):
1646 Number of remaining minutes or seconds
1648 8) min = minutes; sec = seconds */
1650 seq_printf(m
, "%s %d.%d 0x%02x 0x%02x 0x%02x 0x%02x %d%% %d %s\n",
1652 (apm_info
.bios
.version
>> 8) & 0xff,
1653 apm_info
.bios
.version
& 0xff,
1654 apm_info
.bios
.flags
,
1664 static int proc_apm_open(struct inode
*inode
, struct file
*file
)
1666 return single_open(file
, proc_apm_show
, NULL
);
1669 static const struct file_operations apm_file_ops
= {
1670 .owner
= THIS_MODULE
,
1671 .open
= proc_apm_open
,
1673 .llseek
= seq_lseek
,
1674 .release
= single_release
,
1677 static int apm(void *unused
)
1688 * This is to avoid random crashes at boot time during initialization
1689 * on SMP systems in case of "apm=power-off" mode. Seen on ASUS A7M266D.
1690 * Some bioses don't like being called from CPU != 0.
1691 * Method suggested by Ingo Molnar.
1693 set_cpus_allowed(current
, cpumask_of_cpu(0));
1694 BUG_ON(smp_processor_id() != 0);
1697 if (apm_info
.connection_version
== 0) {
1698 apm_info
.connection_version
= apm_info
.bios
.version
;
1699 if (apm_info
.connection_version
> 0x100) {
1701 * We only support BIOSs up to version 1.2
1703 if (apm_info
.connection_version
> 0x0102)
1704 apm_info
.connection_version
= 0x0102;
1705 error
= apm_driver_version(&apm_info
.connection_version
);
1706 if (error
!= APM_SUCCESS
) {
1707 apm_error("driver version", error
);
1708 /* Fall back to an APM 1.0 connection. */
1709 apm_info
.connection_version
= 0x100;
1715 printk(KERN_INFO
"apm: Connection version %d.%d\n",
1716 (apm_info
.connection_version
>> 8) & 0xff,
1717 apm_info
.connection_version
& 0xff);
1719 #ifdef CONFIG_APM_DO_ENABLE
1720 if (apm_info
.bios
.flags
& APM_BIOS_DISABLED
) {
1722 * This call causes my NEC UltraLite Versa 33/C to hang if it
1723 * is booted with PM disabled but not in the docking station.
1726 error
= apm_enable_power_management(1);
1728 apm_error("enable power management", error
);
1734 if ((apm_info
.bios
.flags
& APM_BIOS_DISENGAGED
)
1735 && (apm_info
.connection_version
> 0x0100)) {
1736 error
= apm_engage_power_management(APM_DEVICE_ALL
, 1);
1738 apm_error("engage power management", error
);
1743 if (debug
&& (num_online_cpus() == 1 || smp
)) {
1744 error
= apm_get_power_status(&bx
, &cx
, &dx
);
1746 printk(KERN_INFO
"apm: power status not available\n");
1748 switch ((bx
>> 8) & 0xff) {
1750 power_stat
= "off line";
1753 power_stat
= "on line";
1756 power_stat
= "on backup power";
1759 power_stat
= "unknown";
1762 switch (bx
& 0xff) {
1770 bat_stat
= "critical";
1773 bat_stat
= "charging";
1776 bat_stat
= "unknown";
1780 "apm: AC %s, battery status %s, battery life ",
1781 power_stat
, bat_stat
);
1782 if ((cx
& 0xff) == 0xff)
1783 printk("unknown\n");
1785 printk("%d%%\n", cx
& 0xff);
1786 if (apm_info
.connection_version
> 0x100) {
1788 "apm: battery flag 0x%02x, battery life ",
1791 printk("unknown\n");
1793 printk("%d %s\n", dx
& 0x7fff,
1795 "minutes" : "seconds");
1800 /* Install our power off handler.. */
1802 pm_power_off
= apm_power_off
;
1804 if (num_online_cpus() == 1 || smp
) {
1805 #if defined(CONFIG_APM_DISPLAY_BLANK) && defined(CONFIG_VT)
1806 console_blank_hook
= apm_console_blank
;
1809 #if defined(CONFIG_APM_DISPLAY_BLANK) && defined(CONFIG_VT)
1810 console_blank_hook
= NULL
;
1818 static int __init
apm_setup(char *str
)
1822 while ((str
!= NULL
) && (*str
!= '\0')) {
1823 if (strncmp(str
, "off", 3) == 0)
1825 if (strncmp(str
, "on", 2) == 0)
1827 if ((strncmp(str
, "bounce-interval=", 16) == 0) ||
1828 (strncmp(str
, "bounce_interval=", 16) == 0))
1829 bounce_interval
= simple_strtol(str
+ 16, NULL
, 0);
1830 if ((strncmp(str
, "idle-threshold=", 15) == 0) ||
1831 (strncmp(str
, "idle_threshold=", 15) == 0))
1832 idle_threshold
= simple_strtol(str
+ 15, NULL
, 0);
1833 if ((strncmp(str
, "idle-period=", 12) == 0) ||
1834 (strncmp(str
, "idle_period=", 12) == 0))
1835 idle_period
= simple_strtol(str
+ 12, NULL
, 0);
1836 invert
= (strncmp(str
, "no-", 3) == 0) ||
1837 (strncmp(str
, "no_", 3) == 0);
1840 if (strncmp(str
, "debug", 5) == 0)
1842 if ((strncmp(str
, "power-off", 9) == 0) ||
1843 (strncmp(str
, "power_off", 9) == 0))
1844 power_off
= !invert
;
1845 if (strncmp(str
, "smp", 3) == 0) {
1847 idle_threshold
= 100;
1849 if ((strncmp(str
, "allow-ints", 10) == 0) ||
1850 (strncmp(str
, "allow_ints", 10) == 0))
1851 apm_info
.allow_ints
= !invert
;
1852 if ((strncmp(str
, "broken-psr", 10) == 0) ||
1853 (strncmp(str
, "broken_psr", 10) == 0))
1854 apm_info
.get_power_status_broken
= !invert
;
1855 if ((strncmp(str
, "realmode-power-off", 18) == 0) ||
1856 (strncmp(str
, "realmode_power_off", 18) == 0))
1857 apm_info
.realmode_power_off
= !invert
;
1858 str
= strchr(str
, ',');
1860 str
+= strspn(str
, ", \t");
1865 __setup("apm=", apm_setup
);
1868 static const struct file_operations apm_bios_fops
= {
1869 .owner
= THIS_MODULE
,
1872 .unlocked_ioctl
= do_ioctl
,
1874 .release
= do_release
,
1877 static struct miscdevice apm_device
= {
1884 /* Simple "print if true" callback */
1885 static int __init
print_if_true(const struct dmi_system_id
*d
)
1887 printk("%s\n", d
->ident
);
1892 * Some Bioses enable the PS/2 mouse (touchpad) at resume, even if it was
1893 * disabled before the suspend. Linux used to get terribly confused by that.
1895 static int __init
broken_ps2_resume(const struct dmi_system_id
*d
)
1897 printk(KERN_INFO
"%s machine detected. Mousepad Resume Bug "
1898 "workaround hopefully not needed.\n", d
->ident
);
1902 /* Some bioses have a broken protected mode poweroff and need to use realmode */
1903 static int __init
set_realmode_power_off(const struct dmi_system_id
*d
)
1905 if (apm_info
.realmode_power_off
== 0) {
1906 apm_info
.realmode_power_off
= 1;
1907 printk(KERN_INFO
"%s bios detected. "
1908 "Using realmode poweroff only.\n", d
->ident
);
1913 /* Some laptops require interrupts to be enabled during APM calls */
1914 static int __init
set_apm_ints(const struct dmi_system_id
*d
)
1916 if (apm_info
.allow_ints
== 0) {
1917 apm_info
.allow_ints
= 1;
1918 printk(KERN_INFO
"%s machine detected. "
1919 "Enabling interrupts during APM calls.\n", d
->ident
);
1924 /* Some APM bioses corrupt memory or just plain do not work */
1925 static int __init
apm_is_horked(const struct dmi_system_id
*d
)
1927 if (apm_info
.disabled
== 0) {
1928 apm_info
.disabled
= 1;
1929 printk(KERN_INFO
"%s machine detected. "
1930 "Disabling APM.\n", d
->ident
);
1935 static int __init
apm_is_horked_d850md(const struct dmi_system_id
*d
)
1937 if (apm_info
.disabled
== 0) {
1938 apm_info
.disabled
= 1;
1939 printk(KERN_INFO
"%s machine detected. "
1940 "Disabling APM.\n", d
->ident
);
1941 printk(KERN_INFO
"This bug is fixed in bios P15 which is available for \n");
1942 printk(KERN_INFO
"download from support.intel.com \n");
1947 /* Some APM bioses hang on APM idle calls */
1948 static int __init
apm_likes_to_melt(const struct dmi_system_id
*d
)
1950 if (apm_info
.forbid_idle
== 0) {
1951 apm_info
.forbid_idle
= 1;
1952 printk(KERN_INFO
"%s machine detected. "
1953 "Disabling APM idle calls.\n", d
->ident
);
1959 * Check for clue free BIOS implementations who use
1960 * the following QA technique
1962 * [ Write BIOS Code ]<------
1964 * < Does it Compile >----N--
1966 * < Does it Boot Win98 >-N--
1970 * Phoenix A04 08/24/2000 is known bad (Dell Inspiron 5000e)
1971 * Phoenix A07 09/29/2000 is known good (Dell Inspiron 5000)
1973 static int __init
broken_apm_power(const struct dmi_system_id
*d
)
1975 apm_info
.get_power_status_broken
= 1;
1976 printk(KERN_WARNING
"BIOS strings suggest APM bugs, "
1977 "disabling power status reporting.\n");
1982 * This bios swaps the APM minute reporting bytes over (Many sony laptops
1983 * have this problem).
1985 static int __init
swab_apm_power_in_minutes(const struct dmi_system_id
*d
)
1987 apm_info
.get_power_status_swabinminutes
= 1;
1988 printk(KERN_WARNING
"BIOS strings suggest APM reports battery life "
1989 "in minutes and wrong byte order.\n");
1993 static struct dmi_system_id __initdata apm_dmi_table
[] = {
1996 KERN_WARNING
"IBM T23 - BIOS 1.03b+ and controller firmware 1.02+ may be needed for Linux APM.",
1997 { DMI_MATCH(DMI_SYS_VENDOR
, "IBM"),
1998 DMI_MATCH(DMI_BIOS_VERSION
, "1AET38WW (1.01b)"), },
2000 { /* Handle problems with APM on the C600 */
2001 broken_ps2_resume
, "Dell Latitude C600",
2002 { DMI_MATCH(DMI_SYS_VENDOR
, "Dell"),
2003 DMI_MATCH(DMI_PRODUCT_NAME
, "Latitude C600"), },
2005 { /* Allow interrupts during suspend on Dell Latitude laptops*/
2006 set_apm_ints
, "Dell Latitude",
2007 { DMI_MATCH(DMI_SYS_VENDOR
, "Dell Computer Corporation"),
2008 DMI_MATCH(DMI_PRODUCT_NAME
, "Latitude C510"), }
2011 apm_is_horked
, "Dell Inspiron 2500",
2012 { DMI_MATCH(DMI_SYS_VENDOR
, "Dell Computer Corporation"),
2013 DMI_MATCH(DMI_PRODUCT_NAME
, "Inspiron 2500"),
2014 DMI_MATCH(DMI_BIOS_VENDOR
, "Phoenix Technologies LTD"),
2015 DMI_MATCH(DMI_BIOS_VERSION
, "A11"), },
2017 { /* Allow interrupts during suspend on Dell Inspiron laptops*/
2018 set_apm_ints
, "Dell Inspiron", {
2019 DMI_MATCH(DMI_SYS_VENDOR
, "Dell Computer Corporation"),
2020 DMI_MATCH(DMI_PRODUCT_NAME
, "Inspiron 4000"), },
2022 { /* Handle problems with APM on Inspiron 5000e */
2023 broken_apm_power
, "Dell Inspiron 5000e",
2024 { DMI_MATCH(DMI_BIOS_VENDOR
, "Phoenix Technologies LTD"),
2025 DMI_MATCH(DMI_BIOS_VERSION
, "A04"),
2026 DMI_MATCH(DMI_BIOS_DATE
, "08/24/2000"), },
2028 { /* Handle problems with APM on Inspiron 2500 */
2029 broken_apm_power
, "Dell Inspiron 2500",
2030 { DMI_MATCH(DMI_BIOS_VENDOR
, "Phoenix Technologies LTD"),
2031 DMI_MATCH(DMI_BIOS_VERSION
, "A12"),
2032 DMI_MATCH(DMI_BIOS_DATE
, "02/04/2002"), },
2035 apm_is_horked
, "Dell Dimension 4100",
2036 { DMI_MATCH(DMI_SYS_VENDOR
, "Dell Computer Corporation"),
2037 DMI_MATCH(DMI_PRODUCT_NAME
, "XPS-Z"),
2038 DMI_MATCH(DMI_BIOS_VENDOR
, "Intel Corp."),
2039 DMI_MATCH(DMI_BIOS_VERSION
, "A11"), },
2041 { /* Allow interrupts during suspend on Compaq Laptops*/
2042 set_apm_ints
, "Compaq 12XL125",
2043 { DMI_MATCH(DMI_SYS_VENDOR
, "Compaq"),
2044 DMI_MATCH(DMI_PRODUCT_NAME
, "Compaq PC"),
2045 DMI_MATCH(DMI_BIOS_VENDOR
, "Phoenix Technologies LTD"),
2046 DMI_MATCH(DMI_BIOS_VERSION
, "4.06"), },
2048 { /* Allow interrupts during APM or the clock goes slow */
2049 set_apm_ints
, "ASUSTeK",
2050 { DMI_MATCH(DMI_SYS_VENDOR
, "ASUSTeK Computer Inc."),
2051 DMI_MATCH(DMI_PRODUCT_NAME
, "L8400K series Notebook PC"), },
2053 { /* APM blows on shutdown */
2054 apm_is_horked
, "ABIT KX7-333[R]",
2055 { DMI_MATCH(DMI_BOARD_VENDOR
, "ABIT"),
2056 DMI_MATCH(DMI_BOARD_NAME
, "VT8367-8233A (KX7-333[R])"), },
2059 apm_is_horked
, "Trigem Delhi3",
2060 { DMI_MATCH(DMI_SYS_VENDOR
, "TriGem Computer, Inc"),
2061 DMI_MATCH(DMI_PRODUCT_NAME
, "Delhi3"), },
2064 apm_is_horked
, "Fujitsu-Siemens",
2065 { DMI_MATCH(DMI_BIOS_VENDOR
, "hoenix/FUJITSU SIEMENS"),
2066 DMI_MATCH(DMI_BIOS_VERSION
, "Version1.01"), },
2069 apm_is_horked_d850md
, "Intel D850MD",
2070 { DMI_MATCH(DMI_BIOS_VENDOR
, "Intel Corp."),
2071 DMI_MATCH(DMI_BIOS_VERSION
, "MV85010A.86A.0016.P07.0201251536"), },
2074 apm_is_horked
, "Intel D810EMO",
2075 { DMI_MATCH(DMI_BIOS_VENDOR
, "Intel Corp."),
2076 DMI_MATCH(DMI_BIOS_VERSION
, "MO81010A.86A.0008.P04.0004170800"), },
2079 apm_is_horked
, "Dell XPS-Z",
2080 { DMI_MATCH(DMI_BIOS_VENDOR
, "Intel Corp."),
2081 DMI_MATCH(DMI_BIOS_VERSION
, "A11"),
2082 DMI_MATCH(DMI_PRODUCT_NAME
, "XPS-Z"), },
2085 apm_is_horked
, "Sharp PC-PJ/AX",
2086 { DMI_MATCH(DMI_SYS_VENDOR
, "SHARP"),
2087 DMI_MATCH(DMI_PRODUCT_NAME
, "PC-PJ/AX"),
2088 DMI_MATCH(DMI_BIOS_VENDOR
, "SystemSoft"),
2089 DMI_MATCH(DMI_BIOS_VERSION
, "Version R2.08"), },
2092 apm_is_horked
, "Dell Inspiron 2500",
2093 { DMI_MATCH(DMI_SYS_VENDOR
, "Dell Computer Corporation"),
2094 DMI_MATCH(DMI_PRODUCT_NAME
, "Inspiron 2500"),
2095 DMI_MATCH(DMI_BIOS_VENDOR
, "Phoenix Technologies LTD"),
2096 DMI_MATCH(DMI_BIOS_VERSION
, "A11"), },
2098 { /* APM idle hangs */
2099 apm_likes_to_melt
, "Jabil AMD",
2100 { DMI_MATCH(DMI_BIOS_VENDOR
, "American Megatrends Inc."),
2101 DMI_MATCH(DMI_BIOS_VERSION
, "0AASNP06"), },
2103 { /* APM idle hangs */
2104 apm_likes_to_melt
, "AMI Bios",
2105 { DMI_MATCH(DMI_BIOS_VENDOR
, "American Megatrends Inc."),
2106 DMI_MATCH(DMI_BIOS_VERSION
, "0AASNP05"), },
2108 { /* Handle problems with APM on Sony Vaio PCG-N505X(DE) */
2109 swab_apm_power_in_minutes
, "Sony VAIO",
2110 { DMI_MATCH(DMI_BIOS_VENDOR
, "Phoenix Technologies LTD"),
2111 DMI_MATCH(DMI_BIOS_VERSION
, "R0206H"),
2112 DMI_MATCH(DMI_BIOS_DATE
, "08/23/99"), },
2114 { /* Handle problems with APM on Sony Vaio PCG-N505VX */
2115 swab_apm_power_in_minutes
, "Sony VAIO",
2116 { DMI_MATCH(DMI_BIOS_VENDOR
, "Phoenix Technologies LTD"),
2117 DMI_MATCH(DMI_BIOS_VERSION
, "W2K06H0"),
2118 DMI_MATCH(DMI_BIOS_DATE
, "02/03/00"), },
2120 { /* Handle problems with APM on Sony Vaio PCG-XG29 */
2121 swab_apm_power_in_minutes
, "Sony VAIO",
2122 { DMI_MATCH(DMI_BIOS_VENDOR
, "Phoenix Technologies LTD"),
2123 DMI_MATCH(DMI_BIOS_VERSION
, "R0117A0"),
2124 DMI_MATCH(DMI_BIOS_DATE
, "04/25/00"), },
2126 { /* Handle problems with APM on Sony Vaio PCG-Z600NE */
2127 swab_apm_power_in_minutes
, "Sony VAIO",
2128 { DMI_MATCH(DMI_BIOS_VENDOR
, "Phoenix Technologies LTD"),
2129 DMI_MATCH(DMI_BIOS_VERSION
, "R0121Z1"),
2130 DMI_MATCH(DMI_BIOS_DATE
, "05/11/00"), },
2132 { /* Handle problems with APM on Sony Vaio PCG-Z600NE */
2133 swab_apm_power_in_minutes
, "Sony VAIO",
2134 { DMI_MATCH(DMI_BIOS_VENDOR
, "Phoenix Technologies LTD"),
2135 DMI_MATCH(DMI_BIOS_VERSION
, "WME01Z1"),
2136 DMI_MATCH(DMI_BIOS_DATE
, "08/11/00"), },
2138 { /* Handle problems with APM on Sony Vaio PCG-Z600LEK(DE) */
2139 swab_apm_power_in_minutes
, "Sony VAIO",
2140 { DMI_MATCH(DMI_BIOS_VENDOR
, "Phoenix Technologies LTD"),
2141 DMI_MATCH(DMI_BIOS_VERSION
, "R0206Z3"),
2142 DMI_MATCH(DMI_BIOS_DATE
, "12/25/00"), },
2144 { /* Handle problems with APM on Sony Vaio PCG-Z505LS */
2145 swab_apm_power_in_minutes
, "Sony VAIO",
2146 { DMI_MATCH(DMI_BIOS_VENDOR
, "Phoenix Technologies LTD"),
2147 DMI_MATCH(DMI_BIOS_VERSION
, "R0203D0"),
2148 DMI_MATCH(DMI_BIOS_DATE
, "05/12/00"), },
2150 { /* Handle problems with APM on Sony Vaio PCG-Z505LS */
2151 swab_apm_power_in_minutes
, "Sony VAIO",
2152 { DMI_MATCH(DMI_BIOS_VENDOR
, "Phoenix Technologies LTD"),
2153 DMI_MATCH(DMI_BIOS_VERSION
, "R0203Z3"),
2154 DMI_MATCH(DMI_BIOS_DATE
, "08/25/00"), },
2156 { /* Handle problems with APM on Sony Vaio PCG-Z505LS (with updated BIOS) */
2157 swab_apm_power_in_minutes
, "Sony VAIO",
2158 { DMI_MATCH(DMI_BIOS_VENDOR
, "Phoenix Technologies LTD"),
2159 DMI_MATCH(DMI_BIOS_VERSION
, "R0209Z3"),
2160 DMI_MATCH(DMI_BIOS_DATE
, "05/12/01"), },
2162 { /* Handle problems with APM on Sony Vaio PCG-F104K */
2163 swab_apm_power_in_minutes
, "Sony VAIO",
2164 { DMI_MATCH(DMI_BIOS_VENDOR
, "Phoenix Technologies LTD"),
2165 DMI_MATCH(DMI_BIOS_VERSION
, "R0204K2"),
2166 DMI_MATCH(DMI_BIOS_DATE
, "08/28/00"), },
2169 { /* Handle problems with APM on Sony Vaio PCG-C1VN/C1VE */
2170 swab_apm_power_in_minutes
, "Sony VAIO",
2171 { DMI_MATCH(DMI_BIOS_VENDOR
, "Phoenix Technologies LTD"),
2172 DMI_MATCH(DMI_BIOS_VERSION
, "R0208P1"),
2173 DMI_MATCH(DMI_BIOS_DATE
, "11/09/00"), },
2175 { /* Handle problems with APM on Sony Vaio PCG-C1VE */
2176 swab_apm_power_in_minutes
, "Sony VAIO",
2177 { DMI_MATCH(DMI_BIOS_VENDOR
, "Phoenix Technologies LTD"),
2178 DMI_MATCH(DMI_BIOS_VERSION
, "R0204P1"),
2179 DMI_MATCH(DMI_BIOS_DATE
, "09/12/00"), },
2181 { /* Handle problems with APM on Sony Vaio PCG-C1VE */
2182 swab_apm_power_in_minutes
, "Sony VAIO",
2183 { DMI_MATCH(DMI_BIOS_VENDOR
, "Phoenix Technologies LTD"),
2184 DMI_MATCH(DMI_BIOS_VERSION
, "WXPO1Z3"),
2185 DMI_MATCH(DMI_BIOS_DATE
, "10/26/01"), },
2187 { /* broken PM poweroff bios */
2188 set_realmode_power_off
, "Award Software v4.60 PGMA",
2189 { DMI_MATCH(DMI_BIOS_VENDOR
, "Award Software International, Inc."),
2190 DMI_MATCH(DMI_BIOS_VERSION
, "4.60 PGMA"),
2191 DMI_MATCH(DMI_BIOS_DATE
, "134526184"), },
2194 /* Generic per vendor APM settings */
2196 { /* Allow interrupts during suspend on IBM laptops */
2197 set_apm_ints
, "IBM",
2198 { DMI_MATCH(DMI_SYS_VENDOR
, "IBM"), },
2205 * Just start the APM thread. We do NOT want to do APM BIOS
2206 * calls from anything but the APM thread, if for no other reason
2207 * than the fact that we don't trust the APM BIOS. This way,
2208 * most common APM BIOS problems that lead to protection errors
2209 * etc will have at least some level of being contained...
2211 * In short, if something bad happens, at least we have a choice
2212 * of just killing the apm thread..
2214 static int __init
apm_init(void)
2216 struct desc_struct
*gdt
;
2219 dmi_check_system(apm_dmi_table
);
2221 if (apm_info
.bios
.version
== 0 || paravirt_enabled()) {
2222 printk(KERN_INFO
"apm: BIOS not found.\n");
2226 "apm: BIOS version %d.%d Flags 0x%02x (Driver version %s)\n",
2227 ((apm_info
.bios
.version
>> 8) & 0xff),
2228 (apm_info
.bios
.version
& 0xff),
2229 apm_info
.bios
.flags
,
2231 if ((apm_info
.bios
.flags
& APM_32_BIT_SUPPORT
) == 0) {
2232 printk(KERN_INFO
"apm: no 32 bit BIOS support\n");
2237 apm_info
.allow_ints
= 1;
2239 apm_info
.get_power_status_broken
= 1;
2240 if (realmode_power_off
)
2241 apm_info
.realmode_power_off
= 1;
2242 /* User can override, but default is to trust DMI */
2243 if (apm_disabled
!= -1)
2244 apm_info
.disabled
= apm_disabled
;
2247 * Fix for the Compaq Contura 3/25c which reports BIOS version 0.1
2248 * but is reportedly a 1.0 BIOS.
2250 if (apm_info
.bios
.version
== 0x001)
2251 apm_info
.bios
.version
= 0x100;
2253 /* BIOS < 1.2 doesn't set cseg_16_len */
2254 if (apm_info
.bios
.version
< 0x102)
2255 apm_info
.bios
.cseg_16_len
= 0; /* 64k */
2258 printk(KERN_INFO
"apm: entry %x:%x cseg16 %x dseg %x",
2259 apm_info
.bios
.cseg
, apm_info
.bios
.offset
,
2260 apm_info
.bios
.cseg_16
, apm_info
.bios
.dseg
);
2261 if (apm_info
.bios
.version
> 0x100)
2262 printk(" cseg len %x, dseg len %x",
2263 apm_info
.bios
.cseg_len
,
2264 apm_info
.bios
.dseg_len
);
2265 if (apm_info
.bios
.version
> 0x101)
2266 printk(" cseg16 len %x", apm_info
.bios
.cseg_16_len
);
2270 if (apm_info
.disabled
) {
2271 printk(KERN_NOTICE
"apm: disabled on user request.\n");
2274 if ((num_online_cpus() > 1) && !power_off
&& !smp
) {
2275 printk(KERN_NOTICE
"apm: disabled - APM is not SMP safe.\n");
2276 apm_info
.disabled
= 1;
2279 if (pm_flags
& PM_ACPI
) {
2280 printk(KERN_NOTICE
"apm: overridden by ACPI.\n");
2281 apm_info
.disabled
= 1;
2287 * Set up a segment that references the real mode segment 0x40
2288 * that extends up to the end of page zero (that we have reserved).
2289 * This is for buggy BIOS's that refer to (real mode) segment 0x40
2290 * even though they are called in protected mode.
2292 set_base(bad_bios_desc
, __va((unsigned long)0x40 << 4));
2293 _set_limit((char *)&bad_bios_desc
, 4095 - (0x40 << 4));
2296 * Set up the long jump entry point to the APM BIOS, which is called
2297 * from inline assembly.
2299 apm_bios_entry
.offset
= apm_info
.bios
.offset
;
2300 apm_bios_entry
.segment
= APM_CS
;
2303 * The APM 1.1 BIOS is supposed to provide limit information that it
2304 * recognizes. Many machines do this correctly, but many others do
2305 * not restrict themselves to their claimed limit. When this happens,
2306 * they will cause a segmentation violation in the kernel at boot time.
2307 * Most BIOS's, however, will respect a 64k limit, so we use that.
2309 * Note we only set APM segments on CPU zero, since we pin the APM
2312 gdt
= get_cpu_gdt_table(0);
2313 set_base(gdt
[APM_CS
>> 3],
2314 __va((unsigned long)apm_info
.bios
.cseg
<< 4));
2315 set_base(gdt
[APM_CS_16
>> 3],
2316 __va((unsigned long)apm_info
.bios
.cseg_16
<< 4));
2317 set_base(gdt
[APM_DS
>> 3],
2318 __va((unsigned long)apm_info
.bios
.dseg
<< 4));
2320 proc_create("apm", 0, NULL
, &apm_file_ops
);
2322 kapmd_task
= kthread_create(apm
, NULL
, "kapmd");
2323 if (IS_ERR(kapmd_task
)) {
2324 printk(KERN_ERR
"apm: disabled - Unable to start kernel "
2326 err
= PTR_ERR(kapmd_task
);
2328 remove_proc_entry("apm", NULL
);
2331 wake_up_process(kapmd_task
);
2333 if (num_online_cpus() > 1 && !smp
) {
2335 "apm: disabled - APM is not SMP safe (power off active).\n");
2340 * Note we don't actually care if the misc_device cannot be registered.
2341 * this driver can do its job without it, even if userspace can't
2342 * control it. just log the error
2344 if (misc_register(&apm_device
))
2345 printk(KERN_WARNING
"apm: Could not register misc device.\n");
2348 idle_period
= (idle_period
* HZ
) / 100;
2349 if (idle_threshold
< 100) {
2350 original_pm_idle
= pm_idle
;
2351 pm_idle
= apm_cpu_idle
;
2358 static void __exit
apm_exit(void)
2363 pm_idle
= original_pm_idle
;
2365 * We are about to unload the current idle thread pm callback
2366 * (pm_idle), Wait for all processors to update cached/local
2367 * copies of pm_idle before proceeding.
2371 if (((apm_info
.bios
.flags
& APM_BIOS_DISENGAGED
) == 0)
2372 && (apm_info
.connection_version
> 0x0100)) {
2373 error
= apm_engage_power_management(APM_DEVICE_ALL
, 0);
2375 apm_error("disengage power management", error
);
2377 misc_deregister(&apm_device
);
2378 remove_proc_entry("apm", NULL
);
2380 pm_power_off
= NULL
;
2382 kthread_stop(kapmd_task
);
2385 pm_flags
&= ~PM_APM
;
2388 module_init(apm_init
);
2389 module_exit(apm_exit
);
2391 MODULE_AUTHOR("Stephen Rothwell");
2392 MODULE_DESCRIPTION("Advanced Power Management");
2393 MODULE_LICENSE("GPL");
2394 module_param(debug
, bool, 0644);
2395 MODULE_PARM_DESC(debug
, "Enable debug mode");
2396 module_param(power_off
, bool, 0444);
2397 MODULE_PARM_DESC(power_off
, "Enable power off");
2398 module_param(bounce_interval
, int, 0444);
2399 MODULE_PARM_DESC(bounce_interval
,
2400 "Set the number of ticks to ignore suspend bounces");
2401 module_param(allow_ints
, bool, 0444);
2402 MODULE_PARM_DESC(allow_ints
, "Allow interrupts during BIOS calls");
2403 module_param(broken_psr
, bool, 0444);
2404 MODULE_PARM_DESC(broken_psr
, "BIOS has a broken GetPowerStatus call");
2405 module_param(realmode_power_off
, bool, 0444);
2406 MODULE_PARM_DESC(realmode_power_off
,
2407 "Switch to real mode before powering off");
2408 module_param(idle_threshold
, int, 0444);
2409 MODULE_PARM_DESC(idle_threshold
,
2410 "System idle percentage above which to make APM BIOS idle calls");
2411 module_param(idle_period
, int, 0444);
2412 MODULE_PARM_DESC(idle_period
,
2413 "Period (in sec/100) over which to caculate the idle percentage");
2414 module_param(smp
, bool, 0444);
2415 MODULE_PARM_DESC(smp
,
2416 "Set this to enable APM use on an SMP platform. Use with caution on older systems");
2417 MODULE_ALIAS_MISCDEV(APM_MINOR_DEV
);