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 compiler/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@ucw.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@lxorguk.ukuu.org.uk>).
164 * 1.14ac: If the BIOS says "I slowed the CPU down" then don't spin
165 * calling it - instead idle. (Alan Cox <alan@lxorguk.ukuu.org.uk>)
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 from
193 * http://www.microsoft.com/whdc/archive/amp_12.mspx 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/capability.h>
222 #include <linux/device.h>
223 #include <linux/kernel.h>
224 #include <linux/freezer.h>
225 #include <linux/smp.h>
226 #include <linux/dmi.h>
227 #include <linux/suspend.h>
228 #include <linux/kthread.h>
229 #include <linux/jiffies.h>
230 #include <linux/acpi.h>
231 #include <linux/syscore_ops.h>
233 #include <asm/system.h>
234 #include <asm/uaccess.h>
235 #include <asm/desc.h>
236 #include <asm/i8253.h>
237 #include <asm/olpc.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 static int realmode_power_off
;
396 #ifdef CONFIG_APM_ALLOW_INTS
397 static int allow_ints
= 1;
399 static int allow_ints
;
401 static int broken_psr
;
403 static DECLARE_WAIT_QUEUE_HEAD(apm_waitqueue
);
404 static DECLARE_WAIT_QUEUE_HEAD(apm_suspend_waitqueue
);
405 static struct apm_user
*user_list
;
406 static DEFINE_SPINLOCK(user_list_lock
);
407 static DEFINE_MUTEX(apm_mutex
);
410 * Set up a segment that references the real mode segment 0x40
411 * that extends up to the end of page zero (that we have reserved).
412 * This is for buggy BIOS's that refer to (real mode) segment 0x40
413 * even though they are called in protected mode.
415 static struct desc_struct bad_bios_desc
= GDT_ENTRY_INIT(0x4092,
416 (unsigned long)__va(0x400UL
), PAGE_SIZE
- 0x400 - 1);
418 static const char driver_version
[] = "1.16ac"; /* no spaces */
420 static struct task_struct
*kapmd_task
;
423 * APM event names taken from the APM 1.2 specification. These are
424 * the message codes that the BIOS uses to tell us about events
426 static const char * const apm_event_name
[] = {
432 "power status change",
437 "system standby resume",
438 "capabilities change"
440 #define NR_APM_EVENT_NAME ARRAY_SIZE(apm_event_name)
442 typedef struct lookup_t
{
448 * The BIOS returns a set of standard error codes in AX when the
452 static const lookup_t error_table
[] = {
453 /* N/A { APM_SUCCESS, "Operation succeeded" }, */
454 { APM_DISABLED
, "Power management disabled" },
455 { APM_CONNECTED
, "Real mode interface already connected" },
456 { APM_NOT_CONNECTED
, "Interface not connected" },
457 { APM_16_CONNECTED
, "16 bit interface already connected" },
458 /* N/A { APM_16_UNSUPPORTED, "16 bit interface not supported" }, */
459 { APM_32_CONNECTED
, "32 bit interface already connected" },
460 { APM_32_UNSUPPORTED
, "32 bit interface not supported" },
461 { APM_BAD_DEVICE
, "Unrecognized device ID" },
462 { APM_BAD_PARAM
, "Parameter out of range" },
463 { APM_NOT_ENGAGED
, "Interface not engaged" },
464 { APM_BAD_FUNCTION
, "Function not supported" },
465 { APM_RESUME_DISABLED
, "Resume timer disabled" },
466 { APM_BAD_STATE
, "Unable to enter requested state" },
467 /* N/A { APM_NO_EVENTS, "No events pending" }, */
468 { APM_NO_ERROR
, "BIOS did not set a return code" },
469 { APM_NOT_PRESENT
, "No APM present" }
471 #define ERROR_COUNT ARRAY_SIZE(error_table)
474 * apm_error - display an APM error
475 * @str: information string
476 * @err: APM BIOS return code
478 * Write a meaningful log entry to the kernel log in the event of
479 * an APM error. Note that this also handles (negative) kernel errors.
482 static void apm_error(char *str
, int err
)
486 for (i
= 0; i
< ERROR_COUNT
; i
++)
487 if (error_table
[i
].key
== err
)
490 printk(KERN_NOTICE
"apm: %s: %s\n", str
, error_table
[i
].msg
);
492 printk(KERN_NOTICE
"apm: %s: linux error code %i\n", str
, err
);
494 printk(KERN_NOTICE
"apm: %s: unknown error code %#2.2x\n",
499 * These are the actual BIOS calls. Depending on APM_ZERO_SEGS and
500 * apm_info.allow_ints, we are being really paranoid here! Not only
501 * are interrupts disabled, but all the segment registers (except SS)
502 * are saved and zeroed this means that if the BIOS tries to reference
503 * any data without explicitly loading the segment registers, the kernel
504 * will fault immediately rather than have some unforeseen circumstances
505 * for the rest of the kernel. And it will be very obvious! :-) Doing
506 * this depends on CS referring to the same physical memory as DS so that
507 * DS can be zeroed before the call. Unfortunately, we can't do anything
508 * about the stack segment/pointer. Also, we tell the compiler that
509 * everything could change.
511 * Also, we KNOW that for the non error case of apm_bios_call, there
512 * is no useful data returned in the low order 8 bits of eax.
515 static inline unsigned long __apm_irq_save(void)
518 local_save_flags(flags
);
519 if (apm_info
.allow_ints
) {
520 if (irqs_disabled_flags(flags
))
528 #define apm_irq_save(flags) \
529 do { flags = __apm_irq_save(); } while (0)
531 static inline void apm_irq_restore(unsigned long flags
)
533 if (irqs_disabled_flags(flags
))
535 else if (irqs_disabled())
540 # define APM_DECL_SEGS \
541 unsigned int saved_fs; unsigned int saved_gs;
542 # define APM_DO_SAVE_SEGS \
543 savesegment(fs, saved_fs); savesegment(gs, saved_gs)
544 # define APM_DO_RESTORE_SEGS \
545 loadsegment(fs, saved_fs); loadsegment(gs, saved_gs)
547 # define APM_DECL_SEGS
548 # define APM_DO_SAVE_SEGS
549 # define APM_DO_RESTORE_SEGS
552 struct apm_bios_call
{
562 /* Error: -ENOMEM, or bits 8-15 of eax */
567 * __apm_bios_call - Make an APM BIOS 32bit call
568 * @_call: pointer to struct apm_bios_call.
570 * Make an APM call using the 32bit protected mode interface. The
571 * caller is responsible for knowing if APM BIOS is configured and
572 * enabled. This call can disable interrupts for a long period of
573 * time on some laptops. The return value is in AH and the carry
574 * flag is loaded into AL. If there is an error, then the error
575 * code is returned in AH (bits 8-15 of eax) and this function
578 * Note: this makes the call on the current CPU.
580 static long __apm_bios_call(void *_call
)
585 struct desc_struct save_desc_40
;
586 struct desc_struct
*gdt
;
587 struct apm_bios_call
*call
= _call
;
591 gdt
= get_cpu_gdt_table(cpu
);
592 save_desc_40
= gdt
[0x40 / 8];
593 gdt
[0x40 / 8] = bad_bios_desc
;
597 apm_bios_call_asm(call
->func
, call
->ebx
, call
->ecx
,
598 &call
->eax
, &call
->ebx
, &call
->ecx
, &call
->edx
,
601 apm_irq_restore(flags
);
602 gdt
[0x40 / 8] = save_desc_40
;
605 return call
->eax
& 0xff;
608 /* Run __apm_bios_call or __apm_bios_call_simple on CPU 0 */
609 static int on_cpu0(long (*fn
)(void *), struct apm_bios_call
*call
)
613 /* Don't bother with work_on_cpu in the common case, so we don't
614 * have to worry about OOM or overhead. */
615 if (get_cpu() == 0) {
620 ret
= work_on_cpu(0, fn
, call
);
623 /* work_on_cpu can fail with -ENOMEM */
627 call
->err
= (call
->eax
>> 8) & 0xff;
633 * apm_bios_call - Make an APM BIOS 32bit call (on CPU 0)
634 * @call: the apm_bios_call registers.
636 * If there is an error, it is returned in @call.err.
638 static int apm_bios_call(struct apm_bios_call
*call
)
640 return on_cpu0(__apm_bios_call
, call
);
644 * __apm_bios_call_simple - Make an APM BIOS 32bit call (on CPU 0)
645 * @_call: pointer to struct apm_bios_call.
647 * Make a BIOS call that returns one value only, or just status.
648 * If there is an error, then the error code is returned in AH
649 * (bits 8-15 of eax) and this function returns non-zero (it can
650 * also return -ENOMEM). This is used for simpler BIOS operations.
651 * This call may hold interrupts off for a long time on some laptops.
653 * Note: this makes the call on the current CPU.
655 static long __apm_bios_call_simple(void *_call
)
661 struct desc_struct save_desc_40
;
662 struct desc_struct
*gdt
;
663 struct apm_bios_call
*call
= _call
;
667 gdt
= get_cpu_gdt_table(cpu
);
668 save_desc_40
= gdt
[0x40 / 8];
669 gdt
[0x40 / 8] = bad_bios_desc
;
673 error
= apm_bios_call_simple_asm(call
->func
, call
->ebx
, call
->ecx
,
676 apm_irq_restore(flags
);
677 gdt
[0x40 / 8] = save_desc_40
;
683 * apm_bios_call_simple - make a simple APM BIOS 32bit call
684 * @func: APM function to invoke
685 * @ebx_in: EBX register value for BIOS call
686 * @ecx_in: ECX register value for BIOS call
687 * @eax: EAX register on return from the BIOS call
690 * Make a BIOS call that returns one value only, or just status.
691 * If there is an error, then the error code is returned in @err
692 * and this function returns non-zero. This is used for simpler
693 * BIOS operations. This call may hold interrupts off for a long
694 * time on some laptops.
696 static int apm_bios_call_simple(u32 func
, u32 ebx_in
, u32 ecx_in
, u32
*eax
,
699 struct apm_bios_call call
;
706 ret
= on_cpu0(__apm_bios_call_simple
, &call
);
713 * apm_driver_version - APM driver version
714 * @val: loaded with the APM version on return
716 * Retrieve the APM version supported by the BIOS. This is only
717 * supported for APM 1.1 or higher. An error indicates APM 1.0 is
720 * On entry val should point to a value indicating the APM driver
721 * version with the high byte being the major and the low byte the
722 * minor number both in BCD
724 * On return it will hold the BIOS revision supported in the
728 static int apm_driver_version(u_short
*val
)
733 if (apm_bios_call_simple(APM_FUNC_VERSION
, 0, *val
, &eax
, &err
))
740 * apm_get_event - get an APM event from the BIOS
741 * @event: pointer to the event
742 * @info: point to the event information
744 * The APM BIOS provides a polled information for event
745 * reporting. The BIOS expects to be polled at least every second
746 * when events are pending. When a message is found the caller should
747 * poll until no more messages are present. However, this causes
748 * problems on some laptops where a suspend event notification is
749 * not cleared until it is acknowledged.
751 * Additional information is returned in the info pointer, providing
752 * that APM 1.2 is in use. If no messges are pending the value 0x80
753 * is returned (No power management events pending).
755 static int apm_get_event(apm_event_t
*event
, apm_eventinfo_t
*info
)
757 struct apm_bios_call call
;
759 call
.func
= APM_FUNC_GET_EVENT
;
760 call
.ebx
= call
.ecx
= 0;
762 if (apm_bios_call(&call
))
766 if (apm_info
.connection_version
< 0x0102)
767 *info
= ~0; /* indicate info not valid */
774 * set_power_state - set the power management state
775 * @what: which items to transition
776 * @state: state to transition to
778 * Request an APM change of state for one or more system devices. The
779 * processor state must be transitioned last of all. what holds the
780 * class of device in the upper byte and the device number (0xFF for
781 * all) for the object to be transitioned.
783 * The state holds the state to transition to, which may in fact
784 * be an acceptance of a BIOS requested state change.
787 static int set_power_state(u_short what
, u_short state
)
792 if (apm_bios_call_simple(APM_FUNC_SET_STATE
, what
, state
, &eax
, &err
))
798 * set_system_power_state - set system wide power state
799 * @state: which state to enter
801 * Transition the entire system into a new APM power state.
804 static int set_system_power_state(u_short state
)
806 return set_power_state(APM_DEVICE_ALL
, state
);
810 * apm_do_idle - perform power saving
812 * This function notifies the BIOS that the processor is (in the view
813 * of the OS) idle. It returns -1 in the event that the BIOS refuses
814 * to handle the idle request. On a success the function returns 1
815 * if the BIOS did clock slowing or 0 otherwise.
818 static int apm_do_idle(void)
826 polling
= !!(current_thread_info()->status
& TS_POLLING
);
828 current_thread_info()->status
&= ~TS_POLLING
;
830 * TS_POLLING-cleared state must be visible before we
835 if (!need_resched()) {
837 ret
= apm_bios_call_simple(APM_FUNC_IDLE
, 0, 0, &eax
, &err
);
840 current_thread_info()->status
|= TS_POLLING
;
846 static unsigned long t
;
848 /* This always fails on some SMP boards running UP kernels.
849 * Only report the failure the first 5 times.
852 printk(KERN_DEBUG
"apm_do_idle failed (%d)\n", err
);
857 clock_slowed
= (apm_info
.bios
.flags
& APM_IDLE_SLOWS_CLOCK
) != 0;
862 * apm_do_busy - inform the BIOS the CPU is busy
864 * Request that the BIOS brings the CPU back to full performance.
867 static void apm_do_busy(void)
872 if (clock_slowed
|| ALWAYS_CALL_BUSY
) {
873 (void)apm_bios_call_simple(APM_FUNC_BUSY
, 0, 0, &dummy
, &err
);
879 * If no process has really been interested in
880 * the CPU for some time, we want to call BIOS
881 * power management - we probably want
884 #define IDLE_CALC_LIMIT (HZ * 100)
885 #define IDLE_LEAKY_MAX 16
887 static void (*original_pm_idle
)(void) __read_mostly
;
890 * apm_cpu_idle - cpu idling for APM capable Linux
892 * This is the idling function the kernel executes when APM is available. It
893 * tries to do BIOS powermanagement based on the average system idle time.
894 * Furthermore it calls the system default idle routine.
897 static void apm_cpu_idle(void)
899 static int use_apm_idle
; /* = 0 */
900 static unsigned int last_jiffies
; /* = 0 */
901 static unsigned int last_stime
; /* = 0 */
903 int apm_idle_done
= 0;
904 unsigned int jiffies_since_last_check
= jiffies
- last_jiffies
;
908 if (jiffies_since_last_check
> IDLE_CALC_LIMIT
) {
910 last_jiffies
= jiffies
;
911 last_stime
= current
->stime
;
912 } else if (jiffies_since_last_check
> idle_period
) {
913 unsigned int idle_percentage
;
915 idle_percentage
= current
->stime
- last_stime
;
916 idle_percentage
*= 100;
917 idle_percentage
/= jiffies_since_last_check
;
918 use_apm_idle
= (idle_percentage
> idle_threshold
);
919 if (apm_info
.forbid_idle
)
921 last_jiffies
= jiffies
;
922 last_stime
= current
->stime
;
925 bucket
= IDLE_LEAKY_MAX
;
927 while (!need_resched()) {
932 switch (apm_do_idle()) {
937 bucket
= IDLE_LEAKY_MAX
;
948 default: /* BIOS refused */
952 if (original_pm_idle
)
957 jiffies_since_last_check
= jiffies
- last_jiffies
;
958 if (jiffies_since_last_check
> idle_period
)
969 * apm_power_off - ask the BIOS to power off
971 * Handle the power off sequence. This is the one piece of code we
972 * will execute even on SMP machines. In order to deal with BIOS
973 * bugs we support real mode APM BIOS power off calls. We also make
974 * the SMP call on CPU0 as some systems will only honour this call
975 * on their first cpu.
978 static void apm_power_off(void)
980 /* Some bioses don't like being called from CPU != 0 */
981 if (apm_info
.realmode_power_off
) {
982 set_cpus_allowed_ptr(current
, cpumask_of(0));
983 machine_real_restart(MRR_APM
);
985 (void)set_system_power_state(APM_STATE_OFF
);
989 #ifdef CONFIG_APM_DO_ENABLE
992 * apm_enable_power_management - enable BIOS APM power management
993 * @enable: enable yes/no
995 * Enable or disable the APM BIOS power services.
998 static int apm_enable_power_management(int enable
)
1003 if ((enable
== 0) && (apm_info
.bios
.flags
& APM_BIOS_DISENGAGED
))
1004 return APM_NOT_ENGAGED
;
1005 if (apm_bios_call_simple(APM_FUNC_ENABLE_PM
, APM_DEVICE_BALL
,
1006 enable
, &eax
, &err
))
1009 apm_info
.bios
.flags
&= ~APM_BIOS_DISABLED
;
1011 apm_info
.bios
.flags
|= APM_BIOS_DISABLED
;
1017 * apm_get_power_status - get current power state
1018 * @status: returned status
1019 * @bat: battery info
1020 * @life: estimated life
1022 * Obtain the current power status from the APM BIOS. We return a
1023 * status which gives the rough battery status, and current power
1024 * source. The bat value returned give an estimate as a percentage
1025 * of life and a status value for the battery. The estimated life
1026 * if reported is a lifetime in secodnds/minutes at current powwer
1030 static int apm_get_power_status(u_short
*status
, u_short
*bat
, u_short
*life
)
1032 struct apm_bios_call call
;
1034 call
.func
= APM_FUNC_GET_STATUS
;
1035 call
.ebx
= APM_DEVICE_ALL
;
1038 if (apm_info
.get_power_status_broken
)
1039 return APM_32_UNSUPPORTED
;
1040 if (apm_bios_call(&call
))
1044 if (apm_info
.get_power_status_swabinminutes
) {
1045 *life
= swab16((u16
)call
.edx
);
1053 static int apm_get_battery_status(u_short which
, u_short
*status
,
1054 u_short
*bat
, u_short
*life
, u_short
*nbat
)
1062 if (apm_info
.connection_version
< 0x0102) {
1063 /* pretend we only have one battery. */
1065 return APM_BAD_DEVICE
;
1067 return apm_get_power_status(status
, bat
, life
);
1070 if (apm_bios_call(APM_FUNC_GET_STATUS
, (0x8000 | (which
)), 0, &eax
,
1071 &ebx
, &ecx
, &edx
, &esi
))
1072 return (eax
>> 8) & 0xff;
1082 * apm_engage_power_management - enable PM on a device
1083 * @device: identity of device
1086 * Activate or deactive power management on either a specific device
1087 * or the entire system (%APM_DEVICE_ALL).
1090 static int apm_engage_power_management(u_short device
, int enable
)
1095 if ((enable
== 0) && (device
== APM_DEVICE_ALL
)
1096 && (apm_info
.bios
.flags
& APM_BIOS_DISABLED
))
1097 return APM_DISABLED
;
1098 if (apm_bios_call_simple(APM_FUNC_ENGAGE_PM
, device
, enable
,
1101 if (device
== APM_DEVICE_ALL
) {
1103 apm_info
.bios
.flags
&= ~APM_BIOS_DISENGAGED
;
1105 apm_info
.bios
.flags
|= APM_BIOS_DISENGAGED
;
1110 #if defined(CONFIG_APM_DISPLAY_BLANK) && defined(CONFIG_VT)
1113 * apm_console_blank - blank the display
1116 * Attempt to blank the console, firstly by blanking just video device
1117 * zero, and if that fails (some BIOSes don't support it) then it blanks
1118 * all video devices. Typically the BIOS will do laptop backlight and
1119 * monitor powerdown for us.
1122 static int apm_console_blank(int blank
)
1124 int error
= APM_NOT_ENGAGED
; /* silence gcc */
1127 static const u_short dev
[3] = { 0x100, 0x1FF, 0x101 };
1129 state
= blank
? APM_STATE_STANDBY
: APM_STATE_READY
;
1131 for (i
= 0; i
< ARRAY_SIZE(dev
); i
++) {
1132 error
= set_power_state(dev
[i
], state
);
1134 if ((error
== APM_SUCCESS
) || (error
== APM_NO_ERROR
))
1137 if (error
== APM_NOT_ENGAGED
)
1141 if (error
== APM_NOT_ENGAGED
) {
1145 eng_error
= apm_engage_power_management(APM_DEVICE_ALL
, 1);
1147 apm_error("set display", error
);
1148 apm_error("engage interface", eng_error
);
1151 return apm_console_blank(blank
);
1154 apm_error("set display", error
);
1159 static int queue_empty(struct apm_user
*as
)
1161 return as
->event_head
== as
->event_tail
;
1164 static apm_event_t
get_queued_event(struct apm_user
*as
)
1166 if (++as
->event_tail
>= APM_MAX_EVENTS
)
1168 return as
->events
[as
->event_tail
];
1171 static void queue_event(apm_event_t event
, struct apm_user
*sender
)
1173 struct apm_user
*as
;
1175 spin_lock(&user_list_lock
);
1176 if (user_list
== NULL
)
1178 for (as
= user_list
; as
!= NULL
; as
= as
->next
) {
1179 if ((as
== sender
) || (!as
->reader
))
1181 if (++as
->event_head
>= APM_MAX_EVENTS
)
1184 if (as
->event_head
== as
->event_tail
) {
1185 static int notified
;
1187 if (notified
++ == 0)
1188 printk(KERN_ERR
"apm: an event queue overflowed\n");
1189 if (++as
->event_tail
>= APM_MAX_EVENTS
)
1192 as
->events
[as
->event_head
] = event
;
1193 if (!as
->suser
|| !as
->writer
)
1196 case APM_SYS_SUSPEND
:
1197 case APM_USER_SUSPEND
:
1198 as
->suspends_pending
++;
1202 case APM_SYS_STANDBY
:
1203 case APM_USER_STANDBY
:
1204 as
->standbys_pending
++;
1209 wake_up_interruptible(&apm_waitqueue
);
1211 spin_unlock(&user_list_lock
);
1214 static void reinit_timer(void)
1216 #ifdef INIT_TIMER_AFTER_SUSPEND
1217 unsigned long flags
;
1219 raw_spin_lock_irqsave(&i8253_lock
, flags
);
1220 /* set the clock to HZ */
1221 outb_pit(0x34, PIT_MODE
); /* binary, mode 2, LSB/MSB, ch 0 */
1223 outb_pit(LATCH
& 0xff, PIT_CH0
); /* LSB */
1225 outb_pit(LATCH
>> 8, PIT_CH0
); /* MSB */
1227 raw_spin_unlock_irqrestore(&i8253_lock
, flags
);
1231 static int suspend(int vetoable
)
1234 struct apm_user
*as
;
1236 dpm_suspend_start(PMSG_SUSPEND
);
1238 dpm_suspend_noirq(PMSG_SUSPEND
);
1240 local_irq_disable();
1245 save_processor_state();
1246 err
= set_system_power_state(APM_STATE_SUSPEND
);
1247 ignore_normal_resume
= 1;
1248 restore_processor_state();
1250 local_irq_disable();
1253 if (err
== APM_NO_ERROR
)
1255 if (err
!= APM_SUCCESS
)
1256 apm_error("suspend", err
);
1257 err
= (err
== APM_SUCCESS
) ? 0 : -EIO
;
1262 dpm_resume_noirq(PMSG_RESUME
);
1264 dpm_resume_end(PMSG_RESUME
);
1265 queue_event(APM_NORMAL_RESUME
, NULL
);
1266 spin_lock(&user_list_lock
);
1267 for (as
= user_list
; as
!= NULL
; as
= as
->next
) {
1268 as
->suspend_wait
= 0;
1269 as
->suspend_result
= err
;
1271 spin_unlock(&user_list_lock
);
1272 wake_up_interruptible(&apm_suspend_waitqueue
);
1276 static void standby(void)
1280 dpm_suspend_noirq(PMSG_SUSPEND
);
1282 local_irq_disable();
1286 err
= set_system_power_state(APM_STATE_STANDBY
);
1287 if ((err
!= APM_SUCCESS
) && (err
!= APM_NO_ERROR
))
1288 apm_error("standby", err
);
1290 local_irq_disable();
1294 dpm_resume_noirq(PMSG_RESUME
);
1297 static apm_event_t
get_event(void)
1300 apm_event_t event
= APM_NO_EVENTS
; /* silence gcc */
1301 apm_eventinfo_t info
;
1303 static int notified
;
1305 /* we don't use the eventinfo */
1306 error
= apm_get_event(&event
, &info
);
1307 if (error
== APM_SUCCESS
)
1310 if ((error
!= APM_NO_EVENTS
) && (notified
++ == 0))
1311 apm_error("get_event", error
);
1316 static void check_events(void)
1319 static unsigned long last_resume
;
1320 static int ignore_bounce
;
1322 while ((event
= get_event()) != 0) {
1324 if (event
<= NR_APM_EVENT_NAME
)
1325 printk(KERN_DEBUG
"apm: received %s notify\n",
1326 apm_event_name
[event
- 1]);
1328 printk(KERN_DEBUG
"apm: received unknown "
1329 "event 0x%02x\n", event
);
1332 && (time_after(jiffies
, last_resume
+ bounce_interval
)))
1336 case APM_SYS_STANDBY
:
1337 case APM_USER_STANDBY
:
1338 queue_event(event
, NULL
);
1339 if (standbys_pending
<= 0)
1343 case APM_USER_SUSPEND
:
1344 #ifdef CONFIG_APM_IGNORE_USER_SUSPEND
1345 if (apm_info
.connection_version
> 0x100)
1346 set_system_power_state(APM_STATE_REJECT
);
1349 case APM_SYS_SUSPEND
:
1350 if (ignore_bounce
) {
1351 if (apm_info
.connection_version
> 0x100)
1352 set_system_power_state(APM_STATE_REJECT
);
1356 * If we are already processing a SUSPEND,
1357 * then further SUSPEND events from the BIOS
1358 * will be ignored. We also return here to
1359 * cope with the fact that the Thinkpads keep
1360 * sending a SUSPEND event until something else
1363 if (ignore_sys_suspend
)
1365 ignore_sys_suspend
= 1;
1366 queue_event(event
, NULL
);
1367 if (suspends_pending
<= 0)
1371 case APM_NORMAL_RESUME
:
1372 case APM_CRITICAL_RESUME
:
1373 case APM_STANDBY_RESUME
:
1374 ignore_sys_suspend
= 0;
1375 last_resume
= jiffies
;
1377 if ((event
!= APM_NORMAL_RESUME
)
1378 || (ignore_normal_resume
== 0)) {
1379 dpm_resume_end(PMSG_RESUME
);
1380 queue_event(event
, NULL
);
1382 ignore_normal_resume
= 0;
1385 case APM_CAPABILITY_CHANGE
:
1386 case APM_LOW_BATTERY
:
1387 case APM_POWER_STATUS_CHANGE
:
1388 queue_event(event
, NULL
);
1389 /* If needed, notify drivers here */
1392 case APM_UPDATE_TIME
:
1395 case APM_CRITICAL_SUSPEND
:
1397 * We are not allowed to reject a critical suspend.
1405 static void apm_event_handler(void)
1407 static int pending_count
= 4;
1410 if ((standbys_pending
> 0) || (suspends_pending
> 0)) {
1411 if ((apm_info
.connection_version
> 0x100) &&
1412 (pending_count
-- <= 0)) {
1415 printk(KERN_DEBUG
"apm: setting state busy\n");
1416 err
= set_system_power_state(APM_STATE_BUSY
);
1418 apm_error("busy", err
);
1426 * This is the APM thread main loop.
1429 static void apm_mainloop(void)
1431 DECLARE_WAITQUEUE(wait
, current
);
1433 add_wait_queue(&apm_waitqueue
, &wait
);
1434 set_current_state(TASK_INTERRUPTIBLE
);
1436 schedule_timeout(APM_CHECK_TIMEOUT
);
1437 if (kthread_should_stop())
1440 * Ok, check all events, check for idle (and mark us sleeping
1441 * so as not to count towards the load average)..
1443 set_current_state(TASK_INTERRUPTIBLE
);
1444 apm_event_handler();
1446 remove_wait_queue(&apm_waitqueue
, &wait
);
1449 static int check_apm_user(struct apm_user
*as
, const char *func
)
1451 if (as
== NULL
|| as
->magic
!= APM_BIOS_MAGIC
) {
1452 printk(KERN_ERR
"apm: %s passed bad filp\n", func
);
1458 static ssize_t
do_read(struct file
*fp
, char __user
*buf
, size_t count
, loff_t
*ppos
)
1460 struct apm_user
*as
;
1464 as
= fp
->private_data
;
1465 if (check_apm_user(as
, "read"))
1467 if ((int)count
< sizeof(apm_event_t
))
1469 if ((queue_empty(as
)) && (fp
->f_flags
& O_NONBLOCK
))
1471 wait_event_interruptible(apm_waitqueue
, !queue_empty(as
));
1473 while ((i
>= sizeof(event
)) && !queue_empty(as
)) {
1474 event
= get_queued_event(as
);
1475 if (copy_to_user(buf
, &event
, sizeof(event
))) {
1481 case APM_SYS_SUSPEND
:
1482 case APM_USER_SUSPEND
:
1483 as
->suspends_read
++;
1486 case APM_SYS_STANDBY
:
1487 case APM_USER_STANDBY
:
1488 as
->standbys_read
++;
1491 buf
+= sizeof(event
);
1496 if (signal_pending(current
))
1497 return -ERESTARTSYS
;
1501 static unsigned int do_poll(struct file
*fp
, poll_table
*wait
)
1503 struct apm_user
*as
;
1505 as
= fp
->private_data
;
1506 if (check_apm_user(as
, "poll"))
1508 poll_wait(fp
, &apm_waitqueue
, wait
);
1509 if (!queue_empty(as
))
1510 return POLLIN
| POLLRDNORM
;
1514 static long do_ioctl(struct file
*filp
, u_int cmd
, u_long arg
)
1516 struct apm_user
*as
;
1519 as
= filp
->private_data
;
1520 if (check_apm_user(as
, "ioctl"))
1522 if (!as
->suser
|| !as
->writer
)
1525 case APM_IOC_STANDBY
:
1526 mutex_lock(&apm_mutex
);
1527 if (as
->standbys_read
> 0) {
1528 as
->standbys_read
--;
1529 as
->standbys_pending
--;
1532 queue_event(APM_USER_STANDBY
, as
);
1533 if (standbys_pending
<= 0)
1535 mutex_unlock(&apm_mutex
);
1537 case APM_IOC_SUSPEND
:
1538 mutex_lock(&apm_mutex
);
1539 if (as
->suspends_read
> 0) {
1540 as
->suspends_read
--;
1541 as
->suspends_pending
--;
1544 queue_event(APM_USER_SUSPEND
, as
);
1545 if (suspends_pending
<= 0) {
1547 mutex_unlock(&apm_mutex
);
1549 as
->suspend_wait
= 1;
1550 mutex_unlock(&apm_mutex
);
1551 wait_event_interruptible(apm_suspend_waitqueue
,
1552 as
->suspend_wait
== 0);
1553 ret
= as
->suspend_result
;
1562 static int do_release(struct inode
*inode
, struct file
*filp
)
1564 struct apm_user
*as
;
1566 as
= filp
->private_data
;
1567 if (check_apm_user(as
, "release"))
1569 filp
->private_data
= NULL
;
1570 if (as
->standbys_pending
> 0) {
1571 standbys_pending
-= as
->standbys_pending
;
1572 if (standbys_pending
<= 0)
1575 if (as
->suspends_pending
> 0) {
1576 suspends_pending
-= as
->suspends_pending
;
1577 if (suspends_pending
<= 0)
1580 spin_lock(&user_list_lock
);
1581 if (user_list
== as
)
1582 user_list
= as
->next
;
1584 struct apm_user
*as1
;
1586 for (as1
= user_list
;
1587 (as1
!= NULL
) && (as1
->next
!= as
);
1591 printk(KERN_ERR
"apm: filp not in user list\n");
1593 as1
->next
= as
->next
;
1595 spin_unlock(&user_list_lock
);
1600 static int do_open(struct inode
*inode
, struct file
*filp
)
1602 struct apm_user
*as
;
1604 as
= kmalloc(sizeof(*as
), GFP_KERNEL
);
1606 printk(KERN_ERR
"apm: cannot allocate struct of size %d bytes\n",
1610 as
->magic
= APM_BIOS_MAGIC
;
1611 as
->event_tail
= as
->event_head
= 0;
1612 as
->suspends_pending
= as
->standbys_pending
= 0;
1613 as
->suspends_read
= as
->standbys_read
= 0;
1615 * XXX - this is a tiny bit broken, when we consider BSD
1616 * process accounting. If the device is opened by root, we
1617 * instantly flag that we used superuser privs. Who knows,
1618 * we might close the device immediately without doing a
1619 * privileged operation -- cevans
1621 as
->suser
= capable(CAP_SYS_ADMIN
);
1622 as
->writer
= (filp
->f_mode
& FMODE_WRITE
) == FMODE_WRITE
;
1623 as
->reader
= (filp
->f_mode
& FMODE_READ
) == FMODE_READ
;
1624 spin_lock(&user_list_lock
);
1625 as
->next
= user_list
;
1627 spin_unlock(&user_list_lock
);
1628 filp
->private_data
= as
;
1632 static int proc_apm_show(struct seq_file
*m
, void *v
)
1638 unsigned short ac_line_status
= 0xff;
1639 unsigned short battery_status
= 0xff;
1640 unsigned short battery_flag
= 0xff;
1641 int percentage
= -1;
1642 int time_units
= -1;
1645 if ((num_online_cpus() == 1) &&
1646 !(error
= apm_get_power_status(&bx
, &cx
, &dx
))) {
1647 ac_line_status
= (bx
>> 8) & 0xff;
1648 battery_status
= bx
& 0xff;
1649 if ((cx
& 0xff) != 0xff)
1650 percentage
= cx
& 0xff;
1652 if (apm_info
.connection_version
> 0x100) {
1653 battery_flag
= (cx
>> 8) & 0xff;
1655 units
= (dx
& 0x8000) ? "min" : "sec";
1656 time_units
= dx
& 0x7fff;
1660 /* Arguments, with symbols from linux/apm_bios.h. Information is
1661 from the Get Power Status (0x0a) call unless otherwise noted.
1663 0) Linux driver version (this will change if format changes)
1664 1) APM BIOS Version. Usually 1.0, 1.1 or 1.2.
1665 2) APM flags from APM Installation Check (0x00):
1666 bit 0: APM_16_BIT_SUPPORT
1667 bit 1: APM_32_BIT_SUPPORT
1668 bit 2: APM_IDLE_SLOWS_CLOCK
1669 bit 3: APM_BIOS_DISABLED
1670 bit 4: APM_BIOS_DISENGAGED
1674 0x02: On backup power (BIOS >= 1.1 only)
1681 0x04: Selected battery not present (BIOS >= 1.2 only)
1688 bit 7: No system battery
1690 6) Remaining battery life (percentage of charge):
1693 7) Remaining battery life (time units):
1694 Number of remaining minutes or seconds
1696 8) min = minutes; sec = seconds */
1698 seq_printf(m
, "%s %d.%d 0x%02x 0x%02x 0x%02x 0x%02x %d%% %d %s\n",
1700 (apm_info
.bios
.version
>> 8) & 0xff,
1701 apm_info
.bios
.version
& 0xff,
1702 apm_info
.bios
.flags
,
1712 static int proc_apm_open(struct inode
*inode
, struct file
*file
)
1714 return single_open(file
, proc_apm_show
, NULL
);
1717 static const struct file_operations apm_file_ops
= {
1718 .owner
= THIS_MODULE
,
1719 .open
= proc_apm_open
,
1721 .llseek
= seq_lseek
,
1722 .release
= single_release
,
1725 static int apm(void *unused
)
1735 * This is to avoid random crashes at boot time during initialization
1736 * on SMP systems in case of "apm=power-off" mode. Seen on ASUS A7M266D.
1737 * Some bioses don't like being called from CPU != 0.
1738 * Method suggested by Ingo Molnar.
1740 set_cpus_allowed_ptr(current
, cpumask_of(0));
1741 BUG_ON(smp_processor_id() != 0);
1743 if (apm_info
.connection_version
== 0) {
1744 apm_info
.connection_version
= apm_info
.bios
.version
;
1745 if (apm_info
.connection_version
> 0x100) {
1747 * We only support BIOSs up to version 1.2
1749 if (apm_info
.connection_version
> 0x0102)
1750 apm_info
.connection_version
= 0x0102;
1751 error
= apm_driver_version(&apm_info
.connection_version
);
1752 if (error
!= APM_SUCCESS
) {
1753 apm_error("driver version", error
);
1754 /* Fall back to an APM 1.0 connection. */
1755 apm_info
.connection_version
= 0x100;
1761 printk(KERN_INFO
"apm: Connection version %d.%d\n",
1762 (apm_info
.connection_version
>> 8) & 0xff,
1763 apm_info
.connection_version
& 0xff);
1765 #ifdef CONFIG_APM_DO_ENABLE
1766 if (apm_info
.bios
.flags
& APM_BIOS_DISABLED
) {
1768 * This call causes my NEC UltraLite Versa 33/C to hang if it
1769 * is booted with PM disabled but not in the docking station.
1772 error
= apm_enable_power_management(1);
1774 apm_error("enable power management", error
);
1780 if ((apm_info
.bios
.flags
& APM_BIOS_DISENGAGED
)
1781 && (apm_info
.connection_version
> 0x0100)) {
1782 error
= apm_engage_power_management(APM_DEVICE_ALL
, 1);
1784 apm_error("engage power management", error
);
1789 if (debug
&& (num_online_cpus() == 1 || smp
)) {
1790 error
= apm_get_power_status(&bx
, &cx
, &dx
);
1792 printk(KERN_INFO
"apm: power status not available\n");
1794 switch ((bx
>> 8) & 0xff) {
1796 power_stat
= "off line";
1799 power_stat
= "on line";
1802 power_stat
= "on backup power";
1805 power_stat
= "unknown";
1808 switch (bx
& 0xff) {
1816 bat_stat
= "critical";
1819 bat_stat
= "charging";
1822 bat_stat
= "unknown";
1826 "apm: AC %s, battery status %s, battery life ",
1827 power_stat
, bat_stat
);
1828 if ((cx
& 0xff) == 0xff)
1829 printk("unknown\n");
1831 printk("%d%%\n", cx
& 0xff);
1832 if (apm_info
.connection_version
> 0x100) {
1834 "apm: battery flag 0x%02x, battery life ",
1837 printk("unknown\n");
1839 printk("%d %s\n", dx
& 0x7fff,
1841 "minutes" : "seconds");
1846 /* Install our power off handler.. */
1848 pm_power_off
= apm_power_off
;
1850 if (num_online_cpus() == 1 || smp
) {
1851 #if defined(CONFIG_APM_DISPLAY_BLANK) && defined(CONFIG_VT)
1852 console_blank_hook
= apm_console_blank
;
1855 #if defined(CONFIG_APM_DISPLAY_BLANK) && defined(CONFIG_VT)
1856 console_blank_hook
= NULL
;
1864 static int __init
apm_setup(char *str
)
1868 while ((str
!= NULL
) && (*str
!= '\0')) {
1869 if (strncmp(str
, "off", 3) == 0)
1871 if (strncmp(str
, "on", 2) == 0)
1873 if ((strncmp(str
, "bounce-interval=", 16) == 0) ||
1874 (strncmp(str
, "bounce_interval=", 16) == 0))
1875 bounce_interval
= simple_strtol(str
+ 16, NULL
, 0);
1876 if ((strncmp(str
, "idle-threshold=", 15) == 0) ||
1877 (strncmp(str
, "idle_threshold=", 15) == 0))
1878 idle_threshold
= simple_strtol(str
+ 15, NULL
, 0);
1879 if ((strncmp(str
, "idle-period=", 12) == 0) ||
1880 (strncmp(str
, "idle_period=", 12) == 0))
1881 idle_period
= simple_strtol(str
+ 12, NULL
, 0);
1882 invert
= (strncmp(str
, "no-", 3) == 0) ||
1883 (strncmp(str
, "no_", 3) == 0);
1886 if (strncmp(str
, "debug", 5) == 0)
1888 if ((strncmp(str
, "power-off", 9) == 0) ||
1889 (strncmp(str
, "power_off", 9) == 0))
1890 power_off
= !invert
;
1891 if (strncmp(str
, "smp", 3) == 0) {
1893 idle_threshold
= 100;
1895 if ((strncmp(str
, "allow-ints", 10) == 0) ||
1896 (strncmp(str
, "allow_ints", 10) == 0))
1897 apm_info
.allow_ints
= !invert
;
1898 if ((strncmp(str
, "broken-psr", 10) == 0) ||
1899 (strncmp(str
, "broken_psr", 10) == 0))
1900 apm_info
.get_power_status_broken
= !invert
;
1901 if ((strncmp(str
, "realmode-power-off", 18) == 0) ||
1902 (strncmp(str
, "realmode_power_off", 18) == 0))
1903 apm_info
.realmode_power_off
= !invert
;
1904 str
= strchr(str
, ',');
1906 str
+= strspn(str
, ", \t");
1911 __setup("apm=", apm_setup
);
1914 static const struct file_operations apm_bios_fops
= {
1915 .owner
= THIS_MODULE
,
1918 .unlocked_ioctl
= do_ioctl
,
1920 .release
= do_release
,
1921 .llseek
= noop_llseek
,
1924 static struct miscdevice apm_device
= {
1931 /* Simple "print if true" callback */
1932 static int __init
print_if_true(const struct dmi_system_id
*d
)
1934 printk("%s\n", d
->ident
);
1939 * Some Bioses enable the PS/2 mouse (touchpad) at resume, even if it was
1940 * disabled before the suspend. Linux used to get terribly confused by that.
1942 static int __init
broken_ps2_resume(const struct dmi_system_id
*d
)
1944 printk(KERN_INFO
"%s machine detected. Mousepad Resume Bug "
1945 "workaround hopefully not needed.\n", d
->ident
);
1949 /* Some bioses have a broken protected mode poweroff and need to use realmode */
1950 static int __init
set_realmode_power_off(const struct dmi_system_id
*d
)
1952 if (apm_info
.realmode_power_off
== 0) {
1953 apm_info
.realmode_power_off
= 1;
1954 printk(KERN_INFO
"%s bios detected. "
1955 "Using realmode poweroff only.\n", d
->ident
);
1960 /* Some laptops require interrupts to be enabled during APM calls */
1961 static int __init
set_apm_ints(const struct dmi_system_id
*d
)
1963 if (apm_info
.allow_ints
== 0) {
1964 apm_info
.allow_ints
= 1;
1965 printk(KERN_INFO
"%s machine detected. "
1966 "Enabling interrupts during APM calls.\n", d
->ident
);
1971 /* Some APM bioses corrupt memory or just plain do not work */
1972 static int __init
apm_is_horked(const struct dmi_system_id
*d
)
1974 if (apm_info
.disabled
== 0) {
1975 apm_info
.disabled
= 1;
1976 printk(KERN_INFO
"%s machine detected. "
1977 "Disabling APM.\n", d
->ident
);
1982 static int __init
apm_is_horked_d850md(const struct dmi_system_id
*d
)
1984 if (apm_info
.disabled
== 0) {
1985 apm_info
.disabled
= 1;
1986 printk(KERN_INFO
"%s machine detected. "
1987 "Disabling APM.\n", d
->ident
);
1988 printk(KERN_INFO
"This bug is fixed in bios P15 which is available for\n");
1989 printk(KERN_INFO
"download from support.intel.com\n");
1994 /* Some APM bioses hang on APM idle calls */
1995 static int __init
apm_likes_to_melt(const struct dmi_system_id
*d
)
1997 if (apm_info
.forbid_idle
== 0) {
1998 apm_info
.forbid_idle
= 1;
1999 printk(KERN_INFO
"%s machine detected. "
2000 "Disabling APM idle calls.\n", d
->ident
);
2006 * Check for clue free BIOS implementations who use
2007 * the following QA technique
2009 * [ Write BIOS Code ]<------
2011 * < Does it Compile >----N--
2013 * < Does it Boot Win98 >-N--
2017 * Phoenix A04 08/24/2000 is known bad (Dell Inspiron 5000e)
2018 * Phoenix A07 09/29/2000 is known good (Dell Inspiron 5000)
2020 static int __init
broken_apm_power(const struct dmi_system_id
*d
)
2022 apm_info
.get_power_status_broken
= 1;
2023 printk(KERN_WARNING
"BIOS strings suggest APM bugs, "
2024 "disabling power status reporting.\n");
2029 * This bios swaps the APM minute reporting bytes over (Many sony laptops
2030 * have this problem).
2032 static int __init
swab_apm_power_in_minutes(const struct dmi_system_id
*d
)
2034 apm_info
.get_power_status_swabinminutes
= 1;
2035 printk(KERN_WARNING
"BIOS strings suggest APM reports battery life "
2036 "in minutes and wrong byte order.\n");
2040 static struct dmi_system_id __initdata apm_dmi_table
[] = {
2043 KERN_WARNING
"IBM T23 - BIOS 1.03b+ and controller firmware 1.02+ may be needed for Linux APM.",
2044 { DMI_MATCH(DMI_SYS_VENDOR
, "IBM"),
2045 DMI_MATCH(DMI_BIOS_VERSION
, "1AET38WW (1.01b)"), },
2047 { /* Handle problems with APM on the C600 */
2048 broken_ps2_resume
, "Dell Latitude C600",
2049 { DMI_MATCH(DMI_SYS_VENDOR
, "Dell"),
2050 DMI_MATCH(DMI_PRODUCT_NAME
, "Latitude C600"), },
2052 { /* Allow interrupts during suspend on Dell Latitude laptops*/
2053 set_apm_ints
, "Dell Latitude",
2054 { DMI_MATCH(DMI_SYS_VENDOR
, "Dell Computer Corporation"),
2055 DMI_MATCH(DMI_PRODUCT_NAME
, "Latitude C510"), }
2058 apm_is_horked
, "Dell Inspiron 2500",
2059 { DMI_MATCH(DMI_SYS_VENDOR
, "Dell Computer Corporation"),
2060 DMI_MATCH(DMI_PRODUCT_NAME
, "Inspiron 2500"),
2061 DMI_MATCH(DMI_BIOS_VENDOR
, "Phoenix Technologies LTD"),
2062 DMI_MATCH(DMI_BIOS_VERSION
, "A11"), },
2064 { /* Allow interrupts during suspend on Dell Inspiron laptops*/
2065 set_apm_ints
, "Dell Inspiron", {
2066 DMI_MATCH(DMI_SYS_VENDOR
, "Dell Computer Corporation"),
2067 DMI_MATCH(DMI_PRODUCT_NAME
, "Inspiron 4000"), },
2069 { /* Handle problems with APM on Inspiron 5000e */
2070 broken_apm_power
, "Dell Inspiron 5000e",
2071 { DMI_MATCH(DMI_BIOS_VENDOR
, "Phoenix Technologies LTD"),
2072 DMI_MATCH(DMI_BIOS_VERSION
, "A04"),
2073 DMI_MATCH(DMI_BIOS_DATE
, "08/24/2000"), },
2075 { /* Handle problems with APM on Inspiron 2500 */
2076 broken_apm_power
, "Dell Inspiron 2500",
2077 { DMI_MATCH(DMI_BIOS_VENDOR
, "Phoenix Technologies LTD"),
2078 DMI_MATCH(DMI_BIOS_VERSION
, "A12"),
2079 DMI_MATCH(DMI_BIOS_DATE
, "02/04/2002"), },
2082 apm_is_horked
, "Dell Dimension 4100",
2083 { DMI_MATCH(DMI_SYS_VENDOR
, "Dell Computer Corporation"),
2084 DMI_MATCH(DMI_PRODUCT_NAME
, "XPS-Z"),
2085 DMI_MATCH(DMI_BIOS_VENDOR
, "Intel Corp."),
2086 DMI_MATCH(DMI_BIOS_VERSION
, "A11"), },
2088 { /* Allow interrupts during suspend on Compaq Laptops*/
2089 set_apm_ints
, "Compaq 12XL125",
2090 { DMI_MATCH(DMI_SYS_VENDOR
, "Compaq"),
2091 DMI_MATCH(DMI_PRODUCT_NAME
, "Compaq PC"),
2092 DMI_MATCH(DMI_BIOS_VENDOR
, "Phoenix Technologies LTD"),
2093 DMI_MATCH(DMI_BIOS_VERSION
, "4.06"), },
2095 { /* Allow interrupts during APM or the clock goes slow */
2096 set_apm_ints
, "ASUSTeK",
2097 { DMI_MATCH(DMI_SYS_VENDOR
, "ASUSTeK Computer Inc."),
2098 DMI_MATCH(DMI_PRODUCT_NAME
, "L8400K series Notebook PC"), },
2100 { /* APM blows on shutdown */
2101 apm_is_horked
, "ABIT KX7-333[R]",
2102 { DMI_MATCH(DMI_BOARD_VENDOR
, "ABIT"),
2103 DMI_MATCH(DMI_BOARD_NAME
, "VT8367-8233A (KX7-333[R])"), },
2106 apm_is_horked
, "Trigem Delhi3",
2107 { DMI_MATCH(DMI_SYS_VENDOR
, "TriGem Computer, Inc"),
2108 DMI_MATCH(DMI_PRODUCT_NAME
, "Delhi3"), },
2111 apm_is_horked
, "Fujitsu-Siemens",
2112 { DMI_MATCH(DMI_BIOS_VENDOR
, "hoenix/FUJITSU SIEMENS"),
2113 DMI_MATCH(DMI_BIOS_VERSION
, "Version1.01"), },
2116 apm_is_horked_d850md
, "Intel D850MD",
2117 { DMI_MATCH(DMI_BIOS_VENDOR
, "Intel Corp."),
2118 DMI_MATCH(DMI_BIOS_VERSION
, "MV85010A.86A.0016.P07.0201251536"), },
2121 apm_is_horked
, "Intel D810EMO",
2122 { DMI_MATCH(DMI_BIOS_VENDOR
, "Intel Corp."),
2123 DMI_MATCH(DMI_BIOS_VERSION
, "MO81010A.86A.0008.P04.0004170800"), },
2126 apm_is_horked
, "Dell XPS-Z",
2127 { DMI_MATCH(DMI_BIOS_VENDOR
, "Intel Corp."),
2128 DMI_MATCH(DMI_BIOS_VERSION
, "A11"),
2129 DMI_MATCH(DMI_PRODUCT_NAME
, "XPS-Z"), },
2132 apm_is_horked
, "Sharp PC-PJ/AX",
2133 { DMI_MATCH(DMI_SYS_VENDOR
, "SHARP"),
2134 DMI_MATCH(DMI_PRODUCT_NAME
, "PC-PJ/AX"),
2135 DMI_MATCH(DMI_BIOS_VENDOR
, "SystemSoft"),
2136 DMI_MATCH(DMI_BIOS_VERSION
, "Version R2.08"), },
2139 apm_is_horked
, "Dell Inspiron 2500",
2140 { DMI_MATCH(DMI_SYS_VENDOR
, "Dell Computer Corporation"),
2141 DMI_MATCH(DMI_PRODUCT_NAME
, "Inspiron 2500"),
2142 DMI_MATCH(DMI_BIOS_VENDOR
, "Phoenix Technologies LTD"),
2143 DMI_MATCH(DMI_BIOS_VERSION
, "A11"), },
2145 { /* APM idle hangs */
2146 apm_likes_to_melt
, "Jabil AMD",
2147 { DMI_MATCH(DMI_BIOS_VENDOR
, "American Megatrends Inc."),
2148 DMI_MATCH(DMI_BIOS_VERSION
, "0AASNP06"), },
2150 { /* APM idle hangs */
2151 apm_likes_to_melt
, "AMI Bios",
2152 { DMI_MATCH(DMI_BIOS_VENDOR
, "American Megatrends Inc."),
2153 DMI_MATCH(DMI_BIOS_VERSION
, "0AASNP05"), },
2155 { /* Handle problems with APM on Sony Vaio PCG-N505X(DE) */
2156 swab_apm_power_in_minutes
, "Sony VAIO",
2157 { DMI_MATCH(DMI_BIOS_VENDOR
, "Phoenix Technologies LTD"),
2158 DMI_MATCH(DMI_BIOS_VERSION
, "R0206H"),
2159 DMI_MATCH(DMI_BIOS_DATE
, "08/23/99"), },
2161 { /* Handle problems with APM on Sony Vaio PCG-N505VX */
2162 swab_apm_power_in_minutes
, "Sony VAIO",
2163 { DMI_MATCH(DMI_BIOS_VENDOR
, "Phoenix Technologies LTD"),
2164 DMI_MATCH(DMI_BIOS_VERSION
, "W2K06H0"),
2165 DMI_MATCH(DMI_BIOS_DATE
, "02/03/00"), },
2167 { /* Handle problems with APM on Sony Vaio PCG-XG29 */
2168 swab_apm_power_in_minutes
, "Sony VAIO",
2169 { DMI_MATCH(DMI_BIOS_VENDOR
, "Phoenix Technologies LTD"),
2170 DMI_MATCH(DMI_BIOS_VERSION
, "R0117A0"),
2171 DMI_MATCH(DMI_BIOS_DATE
, "04/25/00"), },
2173 { /* Handle problems with APM on Sony Vaio PCG-Z600NE */
2174 swab_apm_power_in_minutes
, "Sony VAIO",
2175 { DMI_MATCH(DMI_BIOS_VENDOR
, "Phoenix Technologies LTD"),
2176 DMI_MATCH(DMI_BIOS_VERSION
, "R0121Z1"),
2177 DMI_MATCH(DMI_BIOS_DATE
, "05/11/00"), },
2179 { /* Handle problems with APM on Sony Vaio PCG-Z600NE */
2180 swab_apm_power_in_minutes
, "Sony VAIO",
2181 { DMI_MATCH(DMI_BIOS_VENDOR
, "Phoenix Technologies LTD"),
2182 DMI_MATCH(DMI_BIOS_VERSION
, "WME01Z1"),
2183 DMI_MATCH(DMI_BIOS_DATE
, "08/11/00"), },
2185 { /* Handle problems with APM on Sony Vaio PCG-Z600LEK(DE) */
2186 swab_apm_power_in_minutes
, "Sony VAIO",
2187 { DMI_MATCH(DMI_BIOS_VENDOR
, "Phoenix Technologies LTD"),
2188 DMI_MATCH(DMI_BIOS_VERSION
, "R0206Z3"),
2189 DMI_MATCH(DMI_BIOS_DATE
, "12/25/00"), },
2191 { /* Handle problems with APM on Sony Vaio PCG-Z505LS */
2192 swab_apm_power_in_minutes
, "Sony VAIO",
2193 { DMI_MATCH(DMI_BIOS_VENDOR
, "Phoenix Technologies LTD"),
2194 DMI_MATCH(DMI_BIOS_VERSION
, "R0203D0"),
2195 DMI_MATCH(DMI_BIOS_DATE
, "05/12/00"), },
2197 { /* Handle problems with APM on Sony Vaio PCG-Z505LS */
2198 swab_apm_power_in_minutes
, "Sony VAIO",
2199 { DMI_MATCH(DMI_BIOS_VENDOR
, "Phoenix Technologies LTD"),
2200 DMI_MATCH(DMI_BIOS_VERSION
, "R0203Z3"),
2201 DMI_MATCH(DMI_BIOS_DATE
, "08/25/00"), },
2203 { /* Handle problems with APM on Sony Vaio PCG-Z505LS (with updated BIOS) */
2204 swab_apm_power_in_minutes
, "Sony VAIO",
2205 { DMI_MATCH(DMI_BIOS_VENDOR
, "Phoenix Technologies LTD"),
2206 DMI_MATCH(DMI_BIOS_VERSION
, "R0209Z3"),
2207 DMI_MATCH(DMI_BIOS_DATE
, "05/12/01"), },
2209 { /* Handle problems with APM on Sony Vaio PCG-F104K */
2210 swab_apm_power_in_minutes
, "Sony VAIO",
2211 { DMI_MATCH(DMI_BIOS_VENDOR
, "Phoenix Technologies LTD"),
2212 DMI_MATCH(DMI_BIOS_VERSION
, "R0204K2"),
2213 DMI_MATCH(DMI_BIOS_DATE
, "08/28/00"), },
2216 { /* Handle problems with APM on Sony Vaio PCG-C1VN/C1VE */
2217 swab_apm_power_in_minutes
, "Sony VAIO",
2218 { DMI_MATCH(DMI_BIOS_VENDOR
, "Phoenix Technologies LTD"),
2219 DMI_MATCH(DMI_BIOS_VERSION
, "R0208P1"),
2220 DMI_MATCH(DMI_BIOS_DATE
, "11/09/00"), },
2222 { /* Handle problems with APM on Sony Vaio PCG-C1VE */
2223 swab_apm_power_in_minutes
, "Sony VAIO",
2224 { DMI_MATCH(DMI_BIOS_VENDOR
, "Phoenix Technologies LTD"),
2225 DMI_MATCH(DMI_BIOS_VERSION
, "R0204P1"),
2226 DMI_MATCH(DMI_BIOS_DATE
, "09/12/00"), },
2228 { /* Handle problems with APM on Sony Vaio PCG-C1VE */
2229 swab_apm_power_in_minutes
, "Sony VAIO",
2230 { DMI_MATCH(DMI_BIOS_VENDOR
, "Phoenix Technologies LTD"),
2231 DMI_MATCH(DMI_BIOS_VERSION
, "WXPO1Z3"),
2232 DMI_MATCH(DMI_BIOS_DATE
, "10/26/01"), },
2234 { /* broken PM poweroff bios */
2235 set_realmode_power_off
, "Award Software v4.60 PGMA",
2236 { DMI_MATCH(DMI_BIOS_VENDOR
, "Award Software International, Inc."),
2237 DMI_MATCH(DMI_BIOS_VERSION
, "4.60 PGMA"),
2238 DMI_MATCH(DMI_BIOS_DATE
, "134526184"), },
2241 /* Generic per vendor APM settings */
2243 { /* Allow interrupts during suspend on IBM laptops */
2244 set_apm_ints
, "IBM",
2245 { DMI_MATCH(DMI_SYS_VENDOR
, "IBM"), },
2252 * Just start the APM thread. We do NOT want to do APM BIOS
2253 * calls from anything but the APM thread, if for no other reason
2254 * than the fact that we don't trust the APM BIOS. This way,
2255 * most common APM BIOS problems that lead to protection errors
2256 * etc will have at least some level of being contained...
2258 * In short, if something bad happens, at least we have a choice
2259 * of just killing the apm thread..
2261 static int __init
apm_init(void)
2263 struct desc_struct
*gdt
;
2266 dmi_check_system(apm_dmi_table
);
2268 if (apm_info
.bios
.version
== 0 || paravirt_enabled() || machine_is_olpc()) {
2269 printk(KERN_INFO
"apm: BIOS not found.\n");
2273 "apm: BIOS version %d.%d Flags 0x%02x (Driver version %s)\n",
2274 ((apm_info
.bios
.version
>> 8) & 0xff),
2275 (apm_info
.bios
.version
& 0xff),
2276 apm_info
.bios
.flags
,
2278 if ((apm_info
.bios
.flags
& APM_32_BIT_SUPPORT
) == 0) {
2279 printk(KERN_INFO
"apm: no 32 bit BIOS support\n");
2284 apm_info
.allow_ints
= 1;
2286 apm_info
.get_power_status_broken
= 1;
2287 if (realmode_power_off
)
2288 apm_info
.realmode_power_off
= 1;
2289 /* User can override, but default is to trust DMI */
2290 if (apm_disabled
!= -1)
2291 apm_info
.disabled
= apm_disabled
;
2294 * Fix for the Compaq Contura 3/25c which reports BIOS version 0.1
2295 * but is reportedly a 1.0 BIOS.
2297 if (apm_info
.bios
.version
== 0x001)
2298 apm_info
.bios
.version
= 0x100;
2300 /* BIOS < 1.2 doesn't set cseg_16_len */
2301 if (apm_info
.bios
.version
< 0x102)
2302 apm_info
.bios
.cseg_16_len
= 0; /* 64k */
2305 printk(KERN_INFO
"apm: entry %x:%x cseg16 %x dseg %x",
2306 apm_info
.bios
.cseg
, apm_info
.bios
.offset
,
2307 apm_info
.bios
.cseg_16
, apm_info
.bios
.dseg
);
2308 if (apm_info
.bios
.version
> 0x100)
2309 printk(" cseg len %x, dseg len %x",
2310 apm_info
.bios
.cseg_len
,
2311 apm_info
.bios
.dseg_len
);
2312 if (apm_info
.bios
.version
> 0x101)
2313 printk(" cseg16 len %x", apm_info
.bios
.cseg_16_len
);
2317 if (apm_info
.disabled
) {
2318 printk(KERN_NOTICE
"apm: disabled on user request.\n");
2321 if ((num_online_cpus() > 1) && !power_off
&& !smp
) {
2322 printk(KERN_NOTICE
"apm: disabled - APM is not SMP safe.\n");
2323 apm_info
.disabled
= 1;
2326 if (!acpi_disabled
) {
2327 printk(KERN_NOTICE
"apm: overridden by ACPI.\n");
2328 apm_info
.disabled
= 1;
2333 * Set up the long jump entry point to the APM BIOS, which is called
2334 * from inline assembly.
2336 apm_bios_entry
.offset
= apm_info
.bios
.offset
;
2337 apm_bios_entry
.segment
= APM_CS
;
2340 * The APM 1.1 BIOS is supposed to provide limit information that it
2341 * recognizes. Many machines do this correctly, but many others do
2342 * not restrict themselves to their claimed limit. When this happens,
2343 * they will cause a segmentation violation in the kernel at boot time.
2344 * Most BIOS's, however, will respect a 64k limit, so we use that.
2346 * Note we only set APM segments on CPU zero, since we pin the APM
2349 gdt
= get_cpu_gdt_table(0);
2350 set_desc_base(&gdt
[APM_CS
>> 3],
2351 (unsigned long)__va((unsigned long)apm_info
.bios
.cseg
<< 4));
2352 set_desc_base(&gdt
[APM_CS_16
>> 3],
2353 (unsigned long)__va((unsigned long)apm_info
.bios
.cseg_16
<< 4));
2354 set_desc_base(&gdt
[APM_DS
>> 3],
2355 (unsigned long)__va((unsigned long)apm_info
.bios
.dseg
<< 4));
2357 proc_create("apm", 0, NULL
, &apm_file_ops
);
2359 kapmd_task
= kthread_create(apm
, NULL
, "kapmd");
2360 if (IS_ERR(kapmd_task
)) {
2361 printk(KERN_ERR
"apm: disabled - Unable to start kernel "
2363 err
= PTR_ERR(kapmd_task
);
2365 remove_proc_entry("apm", NULL
);
2368 wake_up_process(kapmd_task
);
2370 if (num_online_cpus() > 1 && !smp
) {
2372 "apm: disabled - APM is not SMP safe (power off active).\n");
2377 * Note we don't actually care if the misc_device cannot be registered.
2378 * this driver can do its job without it, even if userspace can't
2379 * control it. just log the error
2381 if (misc_register(&apm_device
))
2382 printk(KERN_WARNING
"apm: Could not register misc device.\n");
2385 idle_period
= (idle_period
* HZ
) / 100;
2386 if (idle_threshold
< 100) {
2387 original_pm_idle
= pm_idle
;
2388 pm_idle
= apm_cpu_idle
;
2395 static void __exit
apm_exit(void)
2400 pm_idle
= original_pm_idle
;
2402 * We are about to unload the current idle thread pm callback
2403 * (pm_idle), Wait for all processors to update cached/local
2404 * copies of pm_idle before proceeding.
2408 if (((apm_info
.bios
.flags
& APM_BIOS_DISENGAGED
) == 0)
2409 && (apm_info
.connection_version
> 0x0100)) {
2410 error
= apm_engage_power_management(APM_DEVICE_ALL
, 0);
2412 apm_error("disengage power management", error
);
2414 misc_deregister(&apm_device
);
2415 remove_proc_entry("apm", NULL
);
2417 pm_power_off
= NULL
;
2419 kthread_stop(kapmd_task
);
2424 module_init(apm_init
);
2425 module_exit(apm_exit
);
2427 MODULE_AUTHOR("Stephen Rothwell");
2428 MODULE_DESCRIPTION("Advanced Power Management");
2429 MODULE_LICENSE("GPL");
2430 module_param(debug
, bool, 0644);
2431 MODULE_PARM_DESC(debug
, "Enable debug mode");
2432 module_param(power_off
, bool, 0444);
2433 MODULE_PARM_DESC(power_off
, "Enable power off");
2434 module_param(bounce_interval
, int, 0444);
2435 MODULE_PARM_DESC(bounce_interval
,
2436 "Set the number of ticks to ignore suspend bounces");
2437 module_param(allow_ints
, bool, 0444);
2438 MODULE_PARM_DESC(allow_ints
, "Allow interrupts during BIOS calls");
2439 module_param(broken_psr
, bool, 0444);
2440 MODULE_PARM_DESC(broken_psr
, "BIOS has a broken GetPowerStatus call");
2441 module_param(realmode_power_off
, bool, 0444);
2442 MODULE_PARM_DESC(realmode_power_off
,
2443 "Switch to real mode before powering off");
2444 module_param(idle_threshold
, int, 0444);
2445 MODULE_PARM_DESC(idle_threshold
,
2446 "System idle percentage above which to make APM BIOS idle calls");
2447 module_param(idle_period
, int, 0444);
2448 MODULE_PARM_DESC(idle_period
,
2449 "Period (in sec/100) over which to caculate the idle percentage");
2450 module_param(smp
, bool, 0444);
2451 MODULE_PARM_DESC(smp
,
2452 "Set this to enable APM use on an SMP platform. Use with caution on older systems");
2453 MODULE_ALIAS_MISCDEV(APM_MINOR_DEV
);