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 #define pr_fmt(fmt) "apm: " fmt
206 #include <linux/module.h>
208 #include <linux/poll.h>
209 #include <linux/types.h>
210 #include <linux/stddef.h>
211 #include <linux/timer.h>
212 #include <linux/fcntl.h>
213 #include <linux/slab.h>
214 #include <linux/stat.h>
215 #include <linux/proc_fs.h>
216 #include <linux/seq_file.h>
217 #include <linux/miscdevice.h>
218 #include <linux/apm_bios.h>
219 #include <linux/init.h>
220 #include <linux/time.h>
221 #include <linux/sched/signal.h>
222 #include <linux/sched/cputime.h>
223 #include <linux/pm.h>
224 #include <linux/capability.h>
225 #include <linux/device.h>
226 #include <linux/kernel.h>
227 #include <linux/freezer.h>
228 #include <linux/smp.h>
229 #include <linux/dmi.h>
230 #include <linux/suspend.h>
231 #include <linux/kthread.h>
232 #include <linux/jiffies.h>
233 #include <linux/acpi.h>
234 #include <linux/syscore_ops.h>
235 #include <linux/i8253.h>
236 #include <linux/cpuidle.h>
238 #include <linux/uaccess.h>
239 #include <asm/desc.h>
240 #include <asm/olpc.h>
241 #include <asm/paravirt.h>
242 #include <asm/reboot.h>
244 #if defined(CONFIG_APM_DISPLAY_BLANK) && defined(CONFIG_VT)
245 extern int (*console_blank_hook)(int);
249 * The apm_bios device is one of the misc char devices.
250 * This is its minor number.
252 #define APM_MINOR_DEV 134
255 * Various options can be changed at boot time as follows:
256 * (We allow underscores for compatibility with the modules code)
257 * apm=on/off enable/disable APM
258 * [no-]allow[-_]ints allow interrupts during BIOS calls
259 * [no-]broken[-_]psr BIOS has a broken GetPowerStatus call
260 * [no-]realmode[-_]power[-_]off switch to real mode before
262 * [no-]debug log some debugging messages
263 * [no-]power[-_]off power off on shutdown
264 * [no-]smp Use apm even on an SMP box
265 * bounce[-_]interval=<n> number of ticks to ignore suspend
267 * idle[-_]threshold=<n> System idle percentage above which to
268 * make APM BIOS idle calls. Set it to
270 * idle[-_]period=<n> Period (in 1/100s of a second) over
271 * which the idle percentage is
275 /* KNOWN PROBLEM MACHINES:
277 * U: TI 4000M TravelMate: BIOS is *NOT* APM compliant
278 * [Confirmed by TI representative]
279 * ?: ACER 486DX4/75: uses dseg 0040, in violation of APM specification
280 * [Confirmed by BIOS disassembly]
281 * [This may work now ...]
282 * P: Toshiba 1950S: battery life information only gets updated after resume
283 * P: Midwest Micro Soundbook Elite DX2/66 monochrome: screen blanking
284 * broken in BIOS [Reported by Garst R. Reese <reese@isn.net>]
285 * ?: AcerNote-950: oops on reading /proc/apm - workaround is a WIP
286 * Neale Banks <neale@lowendale.com.au> December 2000
288 * Legend: U = unusable with APM patches
289 * P = partially usable with APM patches
293 * Define as 1 to make the driver always call the APM BIOS busy
294 * routine even if the clock was not reported as slowed by the
295 * idle routine. Otherwise, define as 0.
297 #define ALWAYS_CALL_BUSY 1
300 * Define to make the APM BIOS calls zero all data segment registers (so
301 * that an incorrect BIOS implementation will cause a kernel panic if it
302 * tries to write to arbitrary memory).
304 #define APM_ZERO_SEGS
309 * Define to re-initialize the interrupt 0 timer to 100 Hz after a suspend.
310 * This patched by Chad Miller <cmiller@surfsouth.com>, original code by
311 * David Chen <chen@ctpa04.mit.edu>
313 #undef INIT_TIMER_AFTER_SUSPEND
315 #ifdef INIT_TIMER_AFTER_SUSPEND
316 #include <linux/timex.h>
318 #include <linux/delay.h>
322 * Need to poll the APM BIOS every second
324 #define APM_CHECK_TIMEOUT (HZ)
327 * Ignore suspend events for this amount of time after a resume
329 #define DEFAULT_BOUNCE_INTERVAL (3 * HZ)
332 * Maximum number of events stored
334 #define APM_MAX_EVENTS 20
337 * The per-file APM data
341 struct apm_user *next;
342 unsigned int suser: 1;
343 unsigned int writer: 1;
344 unsigned int reader: 1;
345 unsigned int suspend_wait: 1;
347 int suspends_pending;
348 int standbys_pending;
353 apm_event_t events[APM_MAX_EVENTS];
357 * The magic number in apm_user
359 #define APM_BIOS_MAGIC 0x4101
362 * idle percentage above which bios idle calls are done
364 #ifdef CONFIG_APM_CPU_IDLE
365 #define DEFAULT_IDLE_THRESHOLD 95
367 #define DEFAULT_IDLE_THRESHOLD 100
369 #define DEFAULT_IDLE_PERIOD (100 / 3)
371 static int apm_cpu_idle(struct cpuidle_device *dev,
372 struct cpuidle_driver *drv, int index);
374 static struct cpuidle_driver apm_idle_driver = {
376 .owner = THIS_MODULE,
378 { /* entry 0 is for polling */ },
379 { /* entry 1 is for APM idle */
382 .exit_latency = 250, /* WAG */
383 .target_residency = 500, /* WAG */
384 .enter = &apm_cpu_idle
390 static struct cpuidle_device apm_cpuidle_device;
396 unsigned long offset;
397 unsigned short segment;
399 static int clock_slowed;
400 static int idle_threshold __read_mostly = DEFAULT_IDLE_THRESHOLD;
401 static int idle_period __read_mostly = DEFAULT_IDLE_PERIOD;
402 static int suspends_pending;
403 static int standbys_pending;
404 static int ignore_sys_suspend;
405 static int ignore_normal_resume;
406 static int bounce_interval __read_mostly = DEFAULT_BOUNCE_INTERVAL;
408 static bool debug __read_mostly;
409 static bool smp __read_mostly;
410 static int apm_disabled = -1;
412 static bool power_off;
414 static bool power_off = 1;
416 static bool realmode_power_off;
417 #ifdef CONFIG_APM_ALLOW_INTS
418 static bool allow_ints = 1;
420 static bool allow_ints;
422 static bool broken_psr;
424 static DECLARE_WAIT_QUEUE_HEAD(apm_waitqueue);
425 static DECLARE_WAIT_QUEUE_HEAD(apm_suspend_waitqueue);
426 static struct apm_user *user_list;
427 static DEFINE_SPINLOCK(user_list_lock);
428 static DEFINE_MUTEX(apm_mutex);
431 * Set up a segment that references the real mode segment 0x40
432 * that extends up to the end of page zero (that we have reserved).
433 * This is for buggy BIOS's that refer to (real mode) segment 0x40
434 * even though they are called in protected mode.
436 static struct desc_struct bad_bios_desc = GDT_ENTRY_INIT(0x4092,
437 (unsigned long)__va(0x400UL), PAGE_SIZE - 0x400 - 1);
439 static const char driver_version[] = "1.16ac"; /* no spaces */
441 static struct task_struct *kapmd_task;
444 * APM event names taken from the APM 1.2 specification. These are
445 * the message codes that the BIOS uses to tell us about events
447 static const char * const apm_event_name[] = {
453 "power status change",
458 "system standby resume",
459 "capabilities change"
461 #define NR_APM_EVENT_NAME ARRAY_SIZE(apm_event_name)
463 typedef struct lookup_t {
469 * The BIOS returns a set of standard error codes in AX when the
473 static const lookup_t error_table[] = {
474 /* N/A { APM_SUCCESS, "Operation succeeded" }, */
475 { APM_DISABLED, "Power management disabled" },
476 { APM_CONNECTED, "Real mode interface already connected" },
477 { APM_NOT_CONNECTED, "Interface not connected" },
478 { APM_16_CONNECTED, "16 bit interface already connected" },
479 /* N/A { APM_16_UNSUPPORTED, "16 bit interface not supported" }, */
480 { APM_32_CONNECTED, "32 bit interface already connected" },
481 { APM_32_UNSUPPORTED, "32 bit interface not supported" },
482 { APM_BAD_DEVICE, "Unrecognized device ID" },
483 { APM_BAD_PARAM, "Parameter out of range" },
484 { APM_NOT_ENGAGED, "Interface not engaged" },
485 { APM_BAD_FUNCTION, "Function not supported" },
486 { APM_RESUME_DISABLED, "Resume timer disabled" },
487 { APM_BAD_STATE, "Unable to enter requested state" },
488 /* N/A { APM_NO_EVENTS, "No events pending" }, */
489 { APM_NO_ERROR, "BIOS did not set a return code" },
490 { APM_NOT_PRESENT, "No APM present" }
492 #define ERROR_COUNT ARRAY_SIZE(error_table)
495 * apm_error - display an APM error
496 * @str: information string
497 * @err: APM BIOS return code
499 * Write a meaningful log entry to the kernel log in the event of
500 * an APM error. Note that this also handles (negative) kernel errors.
503 static void apm_error(char *str, int err)
507 for (i = 0; i < ERROR_COUNT; i++)
508 if (error_table[i].key == err)
511 pr_notice("%s: %s\n", str, error_table[i].msg);
513 pr_notice("%s: linux error code %i\n", str, err);
515 pr_notice("%s: unknown error code %#2.2x\n",
520 * These are the actual BIOS calls. Depending on APM_ZERO_SEGS and
521 * apm_info.allow_ints, we are being really paranoid here! Not only
522 * are interrupts disabled, but all the segment registers (except SS)
523 * are saved and zeroed this means that if the BIOS tries to reference
524 * any data without explicitly loading the segment registers, the kernel
525 * will fault immediately rather than have some unforeseen circumstances
526 * for the rest of the kernel. And it will be very obvious! :-) Doing
527 * this depends on CS referring to the same physical memory as DS so that
528 * DS can be zeroed before the call. Unfortunately, we can't do anything
529 * about the stack segment/pointer. Also, we tell the compiler that
530 * everything could change.
532 * Also, we KNOW that for the non error case of apm_bios_call, there
533 * is no useful data returned in the low order 8 bits of eax.
536 static inline unsigned long __apm_irq_save(void)
539 local_save_flags(flags);
540 if (apm_info.allow_ints) {
541 if (irqs_disabled_flags(flags))
549 #define apm_irq_save(flags) \
550 do { flags = __apm_irq_save(); } while (0)
552 static inline void apm_irq_restore(unsigned long flags)
554 if (irqs_disabled_flags(flags))
556 else if (irqs_disabled())
561 # define APM_DECL_SEGS \
562 unsigned int saved_fs; unsigned int saved_gs;
563 # define APM_DO_SAVE_SEGS \
564 savesegment(fs, saved_fs); savesegment(gs, saved_gs)
565 # define APM_DO_RESTORE_SEGS \
566 loadsegment(fs, saved_fs); loadsegment(gs, saved_gs)
568 # define APM_DECL_SEGS
569 # define APM_DO_SAVE_SEGS
570 # define APM_DO_RESTORE_SEGS
573 struct apm_bios_call {
583 /* Error: -ENOMEM, or bits 8-15 of eax */
588 * __apm_bios_call - Make an APM BIOS 32bit call
589 * @_call: pointer to struct apm_bios_call.
591 * Make an APM call using the 32bit protected mode interface. The
592 * caller is responsible for knowing if APM BIOS is configured and
593 * enabled. This call can disable interrupts for a long period of
594 * time on some laptops. The return value is in AH and the carry
595 * flag is loaded into AL. If there is an error, then the error
596 * code is returned in AH (bits 8-15 of eax) and this function
599 * Note: this makes the call on the current CPU.
601 static long __apm_bios_call(void *_call)
606 struct desc_struct save_desc_40;
607 struct desc_struct *gdt;
608 struct apm_bios_call *call = _call;
612 gdt = get_cpu_gdt_rw(cpu);
613 save_desc_40 = gdt[0x40 / 8];
614 gdt[0x40 / 8] = bad_bios_desc;
618 apm_bios_call_asm(call->func, call->ebx, call->ecx,
619 &call->eax, &call->ebx, &call->ecx, &call->edx,
622 apm_irq_restore(flags);
623 gdt[0x40 / 8] = save_desc_40;
626 return call->eax & 0xff;
629 /* Run __apm_bios_call or __apm_bios_call_simple on CPU 0 */
630 static int on_cpu0(long (*fn)(void *), struct apm_bios_call *call)
634 /* Don't bother with work_on_cpu in the common case, so we don't
635 * have to worry about OOM or overhead. */
636 if (get_cpu() == 0) {
641 ret = work_on_cpu(0, fn, call);
644 /* work_on_cpu can fail with -ENOMEM */
648 call->err = (call->eax >> 8) & 0xff;
654 * apm_bios_call - Make an APM BIOS 32bit call (on CPU 0)
655 * @call: the apm_bios_call registers.
657 * If there is an error, it is returned in @call.err.
659 static int apm_bios_call(struct apm_bios_call *call)
661 return on_cpu0(__apm_bios_call, call);
665 * __apm_bios_call_simple - Make an APM BIOS 32bit call (on CPU 0)
666 * @_call: pointer to struct apm_bios_call.
668 * Make a BIOS call that returns one value only, or just status.
669 * If there is an error, then the error code is returned in AH
670 * (bits 8-15 of eax) and this function returns non-zero (it can
671 * also return -ENOMEM). This is used for simpler BIOS operations.
672 * This call may hold interrupts off for a long time on some laptops.
674 * Note: this makes the call on the current CPU.
676 static long __apm_bios_call_simple(void *_call)
682 struct desc_struct save_desc_40;
683 struct desc_struct *gdt;
684 struct apm_bios_call *call = _call;
688 gdt = get_cpu_gdt_rw(cpu);
689 save_desc_40 = gdt[0x40 / 8];
690 gdt[0x40 / 8] = bad_bios_desc;
694 error = apm_bios_call_simple_asm(call->func, call->ebx, call->ecx,
697 apm_irq_restore(flags);
698 gdt[0x40 / 8] = save_desc_40;
704 * apm_bios_call_simple - make a simple APM BIOS 32bit call
705 * @func: APM function to invoke
706 * @ebx_in: EBX register value for BIOS call
707 * @ecx_in: ECX register value for BIOS call
708 * @eax: EAX register on return from the BIOS call
711 * Make a BIOS call that returns one value only, or just status.
712 * If there is an error, then the error code is returned in @err
713 * and this function returns non-zero. This is used for simpler
714 * BIOS operations. This call may hold interrupts off for a long
715 * time on some laptops.
717 static int apm_bios_call_simple(u32 func, u32 ebx_in, u32 ecx_in, u32 *eax,
720 struct apm_bios_call call;
727 ret = on_cpu0(__apm_bios_call_simple, &call);
734 * apm_driver_version - APM driver version
735 * @val: loaded with the APM version on return
737 * Retrieve the APM version supported by the BIOS. This is only
738 * supported for APM 1.1 or higher. An error indicates APM 1.0 is
741 * On entry val should point to a value indicating the APM driver
742 * version with the high byte being the major and the low byte the
743 * minor number both in BCD
745 * On return it will hold the BIOS revision supported in the
749 static int apm_driver_version(u_short *val)
754 if (apm_bios_call_simple(APM_FUNC_VERSION, 0, *val, &eax, &err))
761 * apm_get_event - get an APM event from the BIOS
762 * @event: pointer to the event
763 * @info: point to the event information
765 * The APM BIOS provides a polled information for event
766 * reporting. The BIOS expects to be polled at least every second
767 * when events are pending. When a message is found the caller should
768 * poll until no more messages are present. However, this causes
769 * problems on some laptops where a suspend event notification is
770 * not cleared until it is acknowledged.
772 * Additional information is returned in the info pointer, providing
773 * that APM 1.2 is in use. If no messges are pending the value 0x80
774 * is returned (No power management events pending).
776 static int apm_get_event(apm_event_t *event, apm_eventinfo_t *info)
778 struct apm_bios_call call;
780 call.func = APM_FUNC_GET_EVENT;
781 call.ebx = call.ecx = 0;
783 if (apm_bios_call(&call))
787 if (apm_info.connection_version < 0x0102)
788 *info = ~0; /* indicate info not valid */
795 * set_power_state - set the power management state
796 * @what: which items to transition
797 * @state: state to transition to
799 * Request an APM change of state for one or more system devices. The
800 * processor state must be transitioned last of all. what holds the
801 * class of device in the upper byte and the device number (0xFF for
802 * all) for the object to be transitioned.
804 * The state holds the state to transition to, which may in fact
805 * be an acceptance of a BIOS requested state change.
808 static int set_power_state(u_short what, u_short state)
813 if (apm_bios_call_simple(APM_FUNC_SET_STATE, what, state, &eax, &err))
819 * set_system_power_state - set system wide power state
820 * @state: which state to enter
822 * Transition the entire system into a new APM power state.
825 static int set_system_power_state(u_short state)
827 return set_power_state(APM_DEVICE_ALL, state);
831 * apm_do_idle - perform power saving
833 * This function notifies the BIOS that the processor is (in the view
834 * of the OS) idle. It returns -1 in the event that the BIOS refuses
835 * to handle the idle request. On a success the function returns 1
836 * if the BIOS did clock slowing or 0 otherwise.
839 static int apm_do_idle(void)
846 if (!need_resched()) {
848 ret = apm_bios_call_simple(APM_FUNC_IDLE, 0, 0, &eax, &err);
855 static unsigned long t;
857 /* This always fails on some SMP boards running UP kernels.
858 * Only report the failure the first 5 times.
861 printk(KERN_DEBUG "apm_do_idle failed (%d)\n", err);
866 clock_slowed = (apm_info.bios.flags & APM_IDLE_SLOWS_CLOCK) != 0;
871 * apm_do_busy - inform the BIOS the CPU is busy
873 * Request that the BIOS brings the CPU back to full performance.
876 static void apm_do_busy(void)
881 if (clock_slowed || ALWAYS_CALL_BUSY) {
882 (void)apm_bios_call_simple(APM_FUNC_BUSY, 0, 0, &dummy, &err);
888 * If no process has really been interested in
889 * the CPU for some time, we want to call BIOS
890 * power management - we probably want
893 #define IDLE_CALC_LIMIT (HZ * 100)
894 #define IDLE_LEAKY_MAX 16
897 * apm_cpu_idle - cpu idling for APM capable Linux
899 * This is the idling function the kernel executes when APM is available. It
900 * tries to do BIOS powermanagement based on the average system idle time.
901 * Furthermore it calls the system default idle routine.
904 static int apm_cpu_idle(struct cpuidle_device *dev,
905 struct cpuidle_driver *drv, int index)
907 static int use_apm_idle; /* = 0 */
908 static unsigned int last_jiffies; /* = 0 */
909 static u64 last_stime; /* = 0 */
912 int apm_idle_done = 0;
913 unsigned int jiffies_since_last_check = jiffies - last_jiffies;
917 task_cputime(current, &utime, &stime);
918 if (jiffies_since_last_check > IDLE_CALC_LIMIT) {
920 } else if (jiffies_since_last_check > idle_period) {
921 unsigned int idle_percentage;
923 idle_percentage = nsecs_to_jiffies(stime - last_stime);
924 idle_percentage *= 100;
925 idle_percentage /= jiffies_since_last_check;
926 use_apm_idle = (idle_percentage > idle_threshold);
927 if (apm_info.forbid_idle)
931 last_jiffies = jiffies;
934 bucket = IDLE_LEAKY_MAX;
936 while (!need_resched()) {
941 switch (apm_do_idle()) {
946 bucket = IDLE_LEAKY_MAX;
957 default: /* BIOS refused */
963 jiffies_since_last_check = jiffies - last_jiffies;
964 if (jiffies_since_last_check > idle_period)
975 * apm_power_off - ask the BIOS to power off
977 * Handle the power off sequence. This is the one piece of code we
978 * will execute even on SMP machines. In order to deal with BIOS
979 * bugs we support real mode APM BIOS power off calls. We also make
980 * the SMP call on CPU0 as some systems will only honour this call
981 * on their first cpu.
984 static void apm_power_off(void)
986 /* Some bioses don't like being called from CPU != 0 */
987 if (apm_info.realmode_power_off) {
988 set_cpus_allowed_ptr(current, cpumask_of(0));
989 machine_real_restart(MRR_APM);
991 (void)set_system_power_state(APM_STATE_OFF);
995 #ifdef CONFIG_APM_DO_ENABLE
998 * apm_enable_power_management - enable BIOS APM power management
999 * @enable: enable yes/no
1001 * Enable or disable the APM BIOS power services.
1004 static int apm_enable_power_management(int enable)
1009 if ((enable == 0) && (apm_info.bios.flags & APM_BIOS_DISENGAGED))
1010 return APM_NOT_ENGAGED;
1011 if (apm_bios_call_simple(APM_FUNC_ENABLE_PM, APM_DEVICE_BALL,
1012 enable, &eax, &err))
1015 apm_info.bios.flags &= ~APM_BIOS_DISABLED;
1017 apm_info.bios.flags |= APM_BIOS_DISABLED;
1023 * apm_get_power_status - get current power state
1024 * @status: returned status
1025 * @bat: battery info
1026 * @life: estimated life
1028 * Obtain the current power status from the APM BIOS. We return a
1029 * status which gives the rough battery status, and current power
1030 * source. The bat value returned give an estimate as a percentage
1031 * of life and a status value for the battery. The estimated life
1032 * if reported is a lifetime in secodnds/minutes at current powwer
1036 static int apm_get_power_status(u_short *status, u_short *bat, u_short *life)
1038 struct apm_bios_call call;
1040 call.func = APM_FUNC_GET_STATUS;
1041 call.ebx = APM_DEVICE_ALL;
1044 if (apm_info.get_power_status_broken)
1045 return APM_32_UNSUPPORTED;
1046 if (apm_bios_call(&call)) {
1048 return APM_NO_ERROR;
1053 if (apm_info.get_power_status_swabinminutes) {
1054 *life = swab16((u16)call.edx);
1062 static int apm_get_battery_status(u_short which, u_short *status,
1063 u_short *bat, u_short *life, u_short *nbat)
1071 if (apm_info.connection_version < 0x0102) {
1072 /* pretend we only have one battery. */
1074 return APM_BAD_DEVICE;
1076 return apm_get_power_status(status, bat, life);
1079 if (apm_bios_call(APM_FUNC_GET_STATUS, (0x8000 | (which)), 0, &eax,
1080 &ebx, &ecx, &edx, &esi))
1081 return (eax >> 8) & 0xff;
1091 * apm_engage_power_management - enable PM on a device
1092 * @device: identity of device
1095 * Activate or deactivate power management on either a specific device
1096 * or the entire system (%APM_DEVICE_ALL).
1099 static int apm_engage_power_management(u_short device, int enable)
1104 if ((enable == 0) && (device == APM_DEVICE_ALL)
1105 && (apm_info.bios.flags & APM_BIOS_DISABLED))
1106 return APM_DISABLED;
1107 if (apm_bios_call_simple(APM_FUNC_ENGAGE_PM, device, enable,
1110 if (device == APM_DEVICE_ALL) {
1112 apm_info.bios.flags &= ~APM_BIOS_DISENGAGED;
1114 apm_info.bios.flags |= APM_BIOS_DISENGAGED;
1119 #if defined(CONFIG_APM_DISPLAY_BLANK) && defined(CONFIG_VT)
1122 * apm_console_blank - blank the display
1125 * Attempt to blank the console, firstly by blanking just video device
1126 * zero, and if that fails (some BIOSes don't support it) then it blanks
1127 * all video devices. Typically the BIOS will do laptop backlight and
1128 * monitor powerdown for us.
1131 static int apm_console_blank(int blank)
1133 int error = APM_NOT_ENGAGED; /* silence gcc */
1136 static const u_short dev[3] = { 0x100, 0x1FF, 0x101 };
1138 state = blank ? APM_STATE_STANDBY : APM_STATE_READY;
1140 for (i = 0; i < ARRAY_SIZE(dev); i++) {
1141 error = set_power_state(dev[i], state);
1143 if ((error == APM_SUCCESS) || (error == APM_NO_ERROR))
1146 if (error == APM_NOT_ENGAGED)
1150 if (error == APM_NOT_ENGAGED) {
1154 eng_error = apm_engage_power_management(APM_DEVICE_ALL, 1);
1156 apm_error("set display", error);
1157 apm_error("engage interface", eng_error);
1160 return apm_console_blank(blank);
1163 apm_error("set display", error);
1168 static int queue_empty(struct apm_user *as)
1170 return as->event_head == as->event_tail;
1173 static apm_event_t get_queued_event(struct apm_user *as)
1175 if (++as->event_tail >= APM_MAX_EVENTS)
1177 return as->events[as->event_tail];
1180 static void queue_event(apm_event_t event, struct apm_user *sender)
1182 struct apm_user *as;
1184 spin_lock(&user_list_lock);
1185 if (user_list == NULL)
1187 for (as = user_list; as != NULL; as = as->next) {
1188 if ((as == sender) || (!as->reader))
1190 if (++as->event_head >= APM_MAX_EVENTS)
1193 if (as->event_head == as->event_tail) {
1194 static int notified;
1196 if (notified++ == 0)
1197 pr_err("an event queue overflowed\n");
1198 if (++as->event_tail >= APM_MAX_EVENTS)
1201 as->events[as->event_head] = event;
1202 if (!as->suser || !as->writer)
1205 case APM_SYS_SUSPEND:
1206 case APM_USER_SUSPEND:
1207 as->suspends_pending++;
1211 case APM_SYS_STANDBY:
1212 case APM_USER_STANDBY:
1213 as->standbys_pending++;
1218 wake_up_interruptible(&apm_waitqueue);
1220 spin_unlock(&user_list_lock);
1223 static void reinit_timer(void)
1225 #ifdef INIT_TIMER_AFTER_SUSPEND
1226 unsigned long flags;
1228 raw_spin_lock_irqsave(&i8253_lock, flags);
1229 /* set the clock to HZ */
1230 outb_p(0x34, PIT_MODE); /* binary, mode 2, LSB/MSB, ch 0 */
1232 outb_p(LATCH & 0xff, PIT_CH0); /* LSB */
1234 outb_p(LATCH >> 8, PIT_CH0); /* MSB */
1236 raw_spin_unlock_irqrestore(&i8253_lock, flags);
1240 static int suspend(int vetoable)
1243 struct apm_user *as;
1245 dpm_suspend_start(PMSG_SUSPEND);
1246 dpm_suspend_end(PMSG_SUSPEND);
1248 local_irq_disable();
1253 save_processor_state();
1254 err = set_system_power_state(APM_STATE_SUSPEND);
1255 ignore_normal_resume = 1;
1256 restore_processor_state();
1258 local_irq_disable();
1261 if (err == APM_NO_ERROR)
1263 if (err != APM_SUCCESS)
1264 apm_error("suspend", err);
1265 err = (err == APM_SUCCESS) ? 0 : -EIO;
1270 dpm_resume_start(PMSG_RESUME);
1271 dpm_resume_end(PMSG_RESUME);
1273 queue_event(APM_NORMAL_RESUME, NULL);
1274 spin_lock(&user_list_lock);
1275 for (as = user_list; as != NULL; as = as->next) {
1276 as->suspend_wait = 0;
1277 as->suspend_result = err;
1279 spin_unlock(&user_list_lock);
1280 wake_up_interruptible(&apm_suspend_waitqueue);
1284 static void standby(void)
1288 dpm_suspend_end(PMSG_SUSPEND);
1290 local_irq_disable();
1294 err = set_system_power_state(APM_STATE_STANDBY);
1295 if ((err != APM_SUCCESS) && (err != APM_NO_ERROR))
1296 apm_error("standby", err);
1298 local_irq_disable();
1302 dpm_resume_start(PMSG_RESUME);
1305 static apm_event_t get_event(void)
1308 apm_event_t event = APM_NO_EVENTS; /* silence gcc */
1309 apm_eventinfo_t info;
1311 static int notified;
1313 /* we don't use the eventinfo */
1314 error = apm_get_event(&event, &info);
1315 if (error == APM_SUCCESS)
1318 if ((error != APM_NO_EVENTS) && (notified++ == 0))
1319 apm_error("get_event", error);
1324 static void check_events(void)
1327 static unsigned long last_resume;
1328 static int ignore_bounce;
1330 while ((event = get_event()) != 0) {
1332 if (event <= NR_APM_EVENT_NAME)
1333 printk(KERN_DEBUG "apm: received %s notify\n",
1334 apm_event_name[event - 1]);
1336 printk(KERN_DEBUG "apm: received unknown "
1337 "event 0x%02x\n", event);
1340 && (time_after(jiffies, last_resume + bounce_interval)))
1344 case APM_SYS_STANDBY:
1345 case APM_USER_STANDBY:
1346 queue_event(event, NULL);
1347 if (standbys_pending <= 0)
1351 case APM_USER_SUSPEND:
1352 #ifdef CONFIG_APM_IGNORE_USER_SUSPEND
1353 if (apm_info.connection_version > 0x100)
1354 set_system_power_state(APM_STATE_REJECT);
1357 case APM_SYS_SUSPEND:
1358 if (ignore_bounce) {
1359 if (apm_info.connection_version > 0x100)
1360 set_system_power_state(APM_STATE_REJECT);
1364 * If we are already processing a SUSPEND,
1365 * then further SUSPEND events from the BIOS
1366 * will be ignored. We also return here to
1367 * cope with the fact that the Thinkpads keep
1368 * sending a SUSPEND event until something else
1371 if (ignore_sys_suspend)
1373 ignore_sys_suspend = 1;
1374 queue_event(event, NULL);
1375 if (suspends_pending <= 0)
1379 case APM_NORMAL_RESUME:
1380 case APM_CRITICAL_RESUME:
1381 case APM_STANDBY_RESUME:
1382 ignore_sys_suspend = 0;
1383 last_resume = jiffies;
1385 if ((event != APM_NORMAL_RESUME)
1386 || (ignore_normal_resume == 0)) {
1387 dpm_resume_end(PMSG_RESUME);
1388 queue_event(event, NULL);
1390 ignore_normal_resume = 0;
1393 case APM_CAPABILITY_CHANGE:
1394 case APM_LOW_BATTERY:
1395 case APM_POWER_STATUS_CHANGE:
1396 queue_event(event, NULL);
1397 /* If needed, notify drivers here */
1400 case APM_UPDATE_TIME:
1403 case APM_CRITICAL_SUSPEND:
1405 * We are not allowed to reject a critical suspend.
1413 static void apm_event_handler(void)
1415 static int pending_count = 4;
1418 if ((standbys_pending > 0) || (suspends_pending > 0)) {
1419 if ((apm_info.connection_version > 0x100) &&
1420 (pending_count-- <= 0)) {
1423 printk(KERN_DEBUG "apm: setting state busy\n");
1424 err = set_system_power_state(APM_STATE_BUSY);
1426 apm_error("busy", err);
1434 * This is the APM thread main loop.
1437 static void apm_mainloop(void)
1439 DECLARE_WAITQUEUE(wait, current);
1441 add_wait_queue(&apm_waitqueue, &wait);
1442 set_current_state(TASK_INTERRUPTIBLE);
1444 schedule_timeout(APM_CHECK_TIMEOUT);
1445 if (kthread_should_stop())
1448 * Ok, check all events, check for idle (and mark us sleeping
1449 * so as not to count towards the load average)..
1451 set_current_state(TASK_INTERRUPTIBLE);
1452 apm_event_handler();
1454 remove_wait_queue(&apm_waitqueue, &wait);
1457 static int check_apm_user(struct apm_user *as, const char *func)
1459 if (as == NULL || as->magic != APM_BIOS_MAGIC) {
1460 pr_err("%s passed bad filp\n", func);
1466 static ssize_t do_read(struct file *fp, char __user *buf, size_t count, loff_t *ppos)
1468 struct apm_user *as;
1472 as = fp->private_data;
1473 if (check_apm_user(as, "read"))
1475 if ((int)count < sizeof(apm_event_t))
1477 if ((queue_empty(as)) && (fp->f_flags & O_NONBLOCK))
1479 wait_event_interruptible(apm_waitqueue, !queue_empty(as));
1481 while ((i >= sizeof(event)) && !queue_empty(as)) {
1482 event = get_queued_event(as);
1483 if (copy_to_user(buf, &event, sizeof(event))) {
1489 case APM_SYS_SUSPEND:
1490 case APM_USER_SUSPEND:
1491 as->suspends_read++;
1494 case APM_SYS_STANDBY:
1495 case APM_USER_STANDBY:
1496 as->standbys_read++;
1499 buf += sizeof(event);
1504 if (signal_pending(current))
1505 return -ERESTARTSYS;
1509 static __poll_t do_poll(struct file *fp, poll_table *wait)
1511 struct apm_user *as;
1513 as = fp->private_data;
1514 if (check_apm_user(as, "poll"))
1516 poll_wait(fp, &apm_waitqueue, wait);
1517 if (!queue_empty(as))
1518 return EPOLLIN | EPOLLRDNORM;
1522 static long do_ioctl(struct file *filp, u_int cmd, u_long arg)
1524 struct apm_user *as;
1527 as = filp->private_data;
1528 if (check_apm_user(as, "ioctl"))
1530 if (!as->suser || !as->writer)
1533 case APM_IOC_STANDBY:
1534 mutex_lock(&apm_mutex);
1535 if (as->standbys_read > 0) {
1536 as->standbys_read--;
1537 as->standbys_pending--;
1540 queue_event(APM_USER_STANDBY, as);
1541 if (standbys_pending <= 0)
1543 mutex_unlock(&apm_mutex);
1545 case APM_IOC_SUSPEND:
1546 mutex_lock(&apm_mutex);
1547 if (as->suspends_read > 0) {
1548 as->suspends_read--;
1549 as->suspends_pending--;
1552 queue_event(APM_USER_SUSPEND, as);
1553 if (suspends_pending <= 0) {
1555 mutex_unlock(&apm_mutex);
1557 as->suspend_wait = 1;
1558 mutex_unlock(&apm_mutex);
1559 wait_event_interruptible(apm_suspend_waitqueue,
1560 as->suspend_wait == 0);
1561 ret = as->suspend_result;
1570 static int do_release(struct inode *inode, struct file *filp)
1572 struct apm_user *as;
1574 as = filp->private_data;
1575 if (check_apm_user(as, "release"))
1577 filp->private_data = NULL;
1578 if (as->standbys_pending > 0) {
1579 standbys_pending -= as->standbys_pending;
1580 if (standbys_pending <= 0)
1583 if (as->suspends_pending > 0) {
1584 suspends_pending -= as->suspends_pending;
1585 if (suspends_pending <= 0)
1588 spin_lock(&user_list_lock);
1589 if (user_list == as)
1590 user_list = as->next;
1592 struct apm_user *as1;
1594 for (as1 = user_list;
1595 (as1 != NULL) && (as1->next != as);
1599 pr_err("filp not in user list\n");
1601 as1->next = as->next;
1603 spin_unlock(&user_list_lock);
1608 static int do_open(struct inode *inode, struct file *filp)
1610 struct apm_user *as;
1612 as = kmalloc(sizeof(*as), GFP_KERNEL);
1616 as->magic = APM_BIOS_MAGIC;
1617 as->event_tail = as->event_head = 0;
1618 as->suspends_pending = as->standbys_pending = 0;
1619 as->suspends_read = as->standbys_read = 0;
1621 * XXX - this is a tiny bit broken, when we consider BSD
1622 * process accounting. If the device is opened by root, we
1623 * instantly flag that we used superuser privs. Who knows,
1624 * we might close the device immediately without doing a
1625 * privileged operation -- cevans
1627 as->suser = capable(CAP_SYS_ADMIN);
1628 as->writer = (filp->f_mode & FMODE_WRITE) == FMODE_WRITE;
1629 as->reader = (filp->f_mode & FMODE_READ) == FMODE_READ;
1630 spin_lock(&user_list_lock);
1631 as->next = user_list;
1633 spin_unlock(&user_list_lock);
1634 filp->private_data = as;
1638 static int proc_apm_show(struct seq_file *m, void *v)
1644 unsigned short ac_line_status = 0xff;
1645 unsigned short battery_status = 0xff;
1646 unsigned short battery_flag = 0xff;
1647 int percentage = -1;
1648 int time_units = -1;
1651 if ((num_online_cpus() == 1) &&
1652 !(error = apm_get_power_status(&bx, &cx, &dx))) {
1653 ac_line_status = (bx >> 8) & 0xff;
1654 battery_status = bx & 0xff;
1655 if ((cx & 0xff) != 0xff)
1656 percentage = cx & 0xff;
1658 if (apm_info.connection_version > 0x100) {
1659 battery_flag = (cx >> 8) & 0xff;
1661 units = (dx & 0x8000) ? "min" : "sec";
1662 time_units = dx & 0x7fff;
1666 /* Arguments, with symbols from linux/apm_bios.h. Information is
1667 from the Get Power Status (0x0a) call unless otherwise noted.
1669 0) Linux driver version (this will change if format changes)
1670 1) APM BIOS Version. Usually 1.0, 1.1 or 1.2.
1671 2) APM flags from APM Installation Check (0x00):
1672 bit 0: APM_16_BIT_SUPPORT
1673 bit 1: APM_32_BIT_SUPPORT
1674 bit 2: APM_IDLE_SLOWS_CLOCK
1675 bit 3: APM_BIOS_DISABLED
1676 bit 4: APM_BIOS_DISENGAGED
1680 0x02: On backup power (BIOS >= 1.1 only)
1687 0x04: Selected battery not present (BIOS >= 1.2 only)
1694 bit 7: No system battery
1696 6) Remaining battery life (percentage of charge):
1699 7) Remaining battery life (time units):
1700 Number of remaining minutes or seconds
1702 8) min = minutes; sec = seconds */
1704 seq_printf(m, "%s %d.%d 0x%02x 0x%02x 0x%02x 0x%02x %d%% %d %s\n",
1706 (apm_info.bios.version >> 8) & 0xff,
1707 apm_info.bios.version & 0xff,
1708 apm_info.bios.flags,
1718 static int apm(void *unused)
1728 * This is to avoid random crashes at boot time during initialization
1729 * on SMP systems in case of "apm=power-off" mode. Seen on ASUS A7M266D.
1730 * Some bioses don't like being called from CPU != 0.
1731 * Method suggested by Ingo Molnar.
1733 set_cpus_allowed_ptr(current, cpumask_of(0));
1734 BUG_ON(smp_processor_id() != 0);
1736 if (apm_info.connection_version == 0) {
1737 apm_info.connection_version = apm_info.bios.version;
1738 if (apm_info.connection_version > 0x100) {
1740 * We only support BIOSs up to version 1.2
1742 if (apm_info.connection_version > 0x0102)
1743 apm_info.connection_version = 0x0102;
1744 error = apm_driver_version(&apm_info.connection_version);
1745 if (error != APM_SUCCESS) {
1746 apm_error("driver version", error);
1747 /* Fall back to an APM 1.0 connection. */
1748 apm_info.connection_version = 0x100;
1754 printk(KERN_INFO "apm: Connection version %d.%d\n",
1755 (apm_info.connection_version >> 8) & 0xff,
1756 apm_info.connection_version & 0xff);
1758 #ifdef CONFIG_APM_DO_ENABLE
1759 if (apm_info.bios.flags & APM_BIOS_DISABLED) {
1761 * This call causes my NEC UltraLite Versa 33/C to hang if it
1762 * is booted with PM disabled but not in the docking station.
1765 error = apm_enable_power_management(1);
1767 apm_error("enable power management", error);
1773 if ((apm_info.bios.flags & APM_BIOS_DISENGAGED)
1774 && (apm_info.connection_version > 0x0100)) {
1775 error = apm_engage_power_management(APM_DEVICE_ALL, 1);
1777 apm_error("engage power management", error);
1782 if (debug && (num_online_cpus() == 1 || smp)) {
1783 error = apm_get_power_status(&bx, &cx, &dx);
1785 printk(KERN_INFO "apm: power status not available\n");
1787 switch ((bx >> 8) & 0xff) {
1789 power_stat = "off line";
1792 power_stat = "on line";
1795 power_stat = "on backup power";
1798 power_stat = "unknown";
1801 switch (bx & 0xff) {
1809 bat_stat = "critical";
1812 bat_stat = "charging";
1815 bat_stat = "unknown";
1819 "apm: AC %s, battery status %s, battery life ",
1820 power_stat, bat_stat);
1821 if ((cx & 0xff) == 0xff)
1822 printk("unknown\n");
1824 printk("%d%%\n", cx & 0xff);
1825 if (apm_info.connection_version > 0x100) {
1827 "apm: battery flag 0x%02x, battery life ",
1830 printk("unknown\n");
1832 printk("%d %s\n", dx & 0x7fff,
1834 "minutes" : "seconds");
1839 /* Install our power off handler.. */
1841 pm_power_off = apm_power_off;
1843 if (num_online_cpus() == 1 || smp) {
1844 #if defined(CONFIG_APM_DISPLAY_BLANK) && defined(CONFIG_VT)
1845 console_blank_hook = apm_console_blank;
1848 #if defined(CONFIG_APM_DISPLAY_BLANK) && defined(CONFIG_VT)
1849 console_blank_hook = NULL;
1857 static int __init apm_setup(char *str)
1861 while ((str != NULL) && (*str != '\0')) {
1862 if (strncmp(str, "off", 3) == 0)
1864 if (strncmp(str, "on", 2) == 0)
1866 if ((strncmp(str, "bounce-interval=", 16) == 0) ||
1867 (strncmp(str, "bounce_interval=", 16) == 0))
1868 bounce_interval = simple_strtol(str + 16, NULL, 0);
1869 if ((strncmp(str, "idle-threshold=", 15) == 0) ||
1870 (strncmp(str, "idle_threshold=", 15) == 0))
1871 idle_threshold = simple_strtol(str + 15, NULL, 0);
1872 if ((strncmp(str, "idle-period=", 12) == 0) ||
1873 (strncmp(str, "idle_period=", 12) == 0))
1874 idle_period = simple_strtol(str + 12, NULL, 0);
1875 invert = (strncmp(str, "no-", 3) == 0) ||
1876 (strncmp(str, "no_", 3) == 0);
1879 if (strncmp(str, "debug", 5) == 0)
1881 if ((strncmp(str, "power-off", 9) == 0) ||
1882 (strncmp(str, "power_off", 9) == 0))
1883 power_off = !invert;
1884 if (strncmp(str, "smp", 3) == 0) {
1886 idle_threshold = 100;
1888 if ((strncmp(str, "allow-ints", 10) == 0) ||
1889 (strncmp(str, "allow_ints", 10) == 0))
1890 apm_info.allow_ints = !invert;
1891 if ((strncmp(str, "broken-psr", 10) == 0) ||
1892 (strncmp(str, "broken_psr", 10) == 0))
1893 apm_info.get_power_status_broken = !invert;
1894 if ((strncmp(str, "realmode-power-off", 18) == 0) ||
1895 (strncmp(str, "realmode_power_off", 18) == 0))
1896 apm_info.realmode_power_off = !invert;
1897 str = strchr(str, ',');
1899 str += strspn(str, ", \t");
1904 __setup("apm=", apm_setup);
1907 static const struct file_operations apm_bios_fops = {
1908 .owner = THIS_MODULE,
1911 .unlocked_ioctl = do_ioctl,
1913 .release = do_release,
1914 .llseek = noop_llseek,
1917 static struct miscdevice apm_device = {
1924 /* Simple "print if true" callback */
1925 static int __init print_if_true(const struct dmi_system_id *d)
1927 printk("%s\n", d->ident);
1932 * Some Bioses enable the PS/2 mouse (touchpad) at resume, even if it was
1933 * disabled before the suspend. Linux used to get terribly confused by that.
1935 static int __init broken_ps2_resume(const struct dmi_system_id *d)
1937 printk(KERN_INFO "%s machine detected. Mousepad Resume Bug "
1938 "workaround hopefully not needed.\n", d->ident);
1942 /* Some bioses have a broken protected mode poweroff and need to use realmode */
1943 static int __init set_realmode_power_off(const struct dmi_system_id *d)
1945 if (apm_info.realmode_power_off == 0) {
1946 apm_info.realmode_power_off = 1;
1947 printk(KERN_INFO "%s bios detected. "
1948 "Using realmode poweroff only.\n", d->ident);
1953 /* Some laptops require interrupts to be enabled during APM calls */
1954 static int __init set_apm_ints(const struct dmi_system_id *d)
1956 if (apm_info.allow_ints == 0) {
1957 apm_info.allow_ints = 1;
1958 printk(KERN_INFO "%s machine detected. "
1959 "Enabling interrupts during APM calls.\n", d->ident);
1964 /* Some APM bioses corrupt memory or just plain do not work */
1965 static int __init apm_is_horked(const struct dmi_system_id *d)
1967 if (apm_info.disabled == 0) {
1968 apm_info.disabled = 1;
1969 printk(KERN_INFO "%s machine detected. "
1970 "Disabling APM.\n", d->ident);
1975 static int __init apm_is_horked_d850md(const struct dmi_system_id *d)
1977 if (apm_info.disabled == 0) {
1978 apm_info.disabled = 1;
1979 printk(KERN_INFO "%s machine detected. "
1980 "Disabling APM.\n", d->ident);
1981 printk(KERN_INFO "This bug is fixed in bios P15 which is available for\n");
1982 printk(KERN_INFO "download from support.intel.com\n");
1987 /* Some APM bioses hang on APM idle calls */
1988 static int __init apm_likes_to_melt(const struct dmi_system_id *d)
1990 if (apm_info.forbid_idle == 0) {
1991 apm_info.forbid_idle = 1;
1992 printk(KERN_INFO "%s machine detected. "
1993 "Disabling APM idle calls.\n", d->ident);
1999 * Check for clue free BIOS implementations who use
2000 * the following QA technique
2002 * [ Write BIOS Code ]<------
2004 * < Does it Compile >----N--
2006 * < Does it Boot Win98 >-N--
2010 * Phoenix A04 08/24/2000 is known bad (Dell Inspiron 5000e)
2011 * Phoenix A07 09/29/2000 is known good (Dell Inspiron 5000)
2013 static int __init broken_apm_power(const struct dmi_system_id *d)
2015 apm_info.get_power_status_broken = 1;
2016 printk(KERN_WARNING "BIOS strings suggest APM bugs, "
2017 "disabling power status reporting.\n");
2022 * This bios swaps the APM minute reporting bytes over (Many sony laptops
2023 * have this problem).
2025 static int __init swab_apm_power_in_minutes(const struct dmi_system_id *d)
2027 apm_info.get_power_status_swabinminutes = 1;
2028 printk(KERN_WARNING "BIOS strings suggest APM reports battery life "
2029 "in minutes and wrong byte order.\n");
2033 static const struct dmi_system_id apm_dmi_table[] __initconst = {
2036 KERN_WARNING "IBM T23 - BIOS 1.03b+ and controller firmware 1.02+ may be needed for Linux APM.",
2037 { DMI_MATCH(DMI_SYS_VENDOR, "IBM"),
2038 DMI_MATCH(DMI_BIOS_VERSION, "1AET38WW (1.01b)"), },
2040 { /* Handle problems with APM on the C600 */
2041 broken_ps2_resume, "Dell Latitude C600",
2042 { DMI_MATCH(DMI_SYS_VENDOR, "Dell"),
2043 DMI_MATCH(DMI_PRODUCT_NAME, "Latitude C600"), },
2045 { /* Allow interrupts during suspend on Dell Latitude laptops*/
2046 set_apm_ints, "Dell Latitude",
2047 { DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
2048 DMI_MATCH(DMI_PRODUCT_NAME, "Latitude C510"), }
2051 apm_is_horked, "Dell Inspiron 2500",
2052 { DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
2053 DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 2500"),
2054 DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2055 DMI_MATCH(DMI_BIOS_VERSION, "A11"), },
2057 { /* Allow interrupts during suspend on Dell Inspiron laptops*/
2058 set_apm_ints, "Dell Inspiron", {
2059 DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
2060 DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 4000"), },
2062 { /* Handle problems with APM on Inspiron 5000e */
2063 broken_apm_power, "Dell Inspiron 5000e",
2064 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2065 DMI_MATCH(DMI_BIOS_VERSION, "A04"),
2066 DMI_MATCH(DMI_BIOS_DATE, "08/24/2000"), },
2068 { /* Handle problems with APM on Inspiron 2500 */
2069 broken_apm_power, "Dell Inspiron 2500",
2070 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2071 DMI_MATCH(DMI_BIOS_VERSION, "A12"),
2072 DMI_MATCH(DMI_BIOS_DATE, "02/04/2002"), },
2075 apm_is_horked, "Dell Dimension 4100",
2076 { DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
2077 DMI_MATCH(DMI_PRODUCT_NAME, "XPS-Z"),
2078 DMI_MATCH(DMI_BIOS_VENDOR, "Intel Corp."),
2079 DMI_MATCH(DMI_BIOS_VERSION, "A11"), },
2081 { /* Allow interrupts during suspend on Compaq Laptops*/
2082 set_apm_ints, "Compaq 12XL125",
2083 { DMI_MATCH(DMI_SYS_VENDOR, "Compaq"),
2084 DMI_MATCH(DMI_PRODUCT_NAME, "Compaq PC"),
2085 DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2086 DMI_MATCH(DMI_BIOS_VERSION, "4.06"), },
2088 { /* Allow interrupts during APM or the clock goes slow */
2089 set_apm_ints, "ASUSTeK",
2090 { DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK Computer Inc."),
2091 DMI_MATCH(DMI_PRODUCT_NAME, "L8400K series Notebook PC"), },
2093 { /* APM blows on shutdown */
2094 apm_is_horked, "ABIT KX7-333[R]",
2095 { DMI_MATCH(DMI_BOARD_VENDOR, "ABIT"),
2096 DMI_MATCH(DMI_BOARD_NAME, "VT8367-8233A (KX7-333[R])"), },
2099 apm_is_horked, "Trigem Delhi3",
2100 { DMI_MATCH(DMI_SYS_VENDOR, "TriGem Computer, Inc"),
2101 DMI_MATCH(DMI_PRODUCT_NAME, "Delhi3"), },
2104 apm_is_horked, "Fujitsu-Siemens",
2105 { DMI_MATCH(DMI_BIOS_VENDOR, "hoenix/FUJITSU SIEMENS"),
2106 DMI_MATCH(DMI_BIOS_VERSION, "Version1.01"), },
2109 apm_is_horked_d850md, "Intel D850MD",
2110 { DMI_MATCH(DMI_BIOS_VENDOR, "Intel Corp."),
2111 DMI_MATCH(DMI_BIOS_VERSION, "MV85010A.86A.0016.P07.0201251536"), },
2114 apm_is_horked, "Intel D810EMO",
2115 { DMI_MATCH(DMI_BIOS_VENDOR, "Intel Corp."),
2116 DMI_MATCH(DMI_BIOS_VERSION, "MO81010A.86A.0008.P04.0004170800"), },
2119 apm_is_horked, "Dell XPS-Z",
2120 { DMI_MATCH(DMI_BIOS_VENDOR, "Intel Corp."),
2121 DMI_MATCH(DMI_BIOS_VERSION, "A11"),
2122 DMI_MATCH(DMI_PRODUCT_NAME, "XPS-Z"), },
2125 apm_is_horked, "Sharp PC-PJ/AX",
2126 { DMI_MATCH(DMI_SYS_VENDOR, "SHARP"),
2127 DMI_MATCH(DMI_PRODUCT_NAME, "PC-PJ/AX"),
2128 DMI_MATCH(DMI_BIOS_VENDOR, "SystemSoft"),
2129 DMI_MATCH(DMI_BIOS_VERSION, "Version R2.08"), },
2132 apm_is_horked, "Dell Inspiron 2500",
2133 { DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
2134 DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 2500"),
2135 DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2136 DMI_MATCH(DMI_BIOS_VERSION, "A11"), },
2138 { /* APM idle hangs */
2139 apm_likes_to_melt, "Jabil AMD",
2140 { DMI_MATCH(DMI_BIOS_VENDOR, "American Megatrends Inc."),
2141 DMI_MATCH(DMI_BIOS_VERSION, "0AASNP06"), },
2143 { /* APM idle hangs */
2144 apm_likes_to_melt, "AMI Bios",
2145 { DMI_MATCH(DMI_BIOS_VENDOR, "American Megatrends Inc."),
2146 DMI_MATCH(DMI_BIOS_VERSION, "0AASNP05"), },
2148 { /* Handle problems with APM on Sony Vaio PCG-N505X(DE) */
2149 swab_apm_power_in_minutes, "Sony VAIO",
2150 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2151 DMI_MATCH(DMI_BIOS_VERSION, "R0206H"),
2152 DMI_MATCH(DMI_BIOS_DATE, "08/23/99"), },
2154 { /* Handle problems with APM on Sony Vaio PCG-N505VX */
2155 swab_apm_power_in_minutes, "Sony VAIO",
2156 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2157 DMI_MATCH(DMI_BIOS_VERSION, "W2K06H0"),
2158 DMI_MATCH(DMI_BIOS_DATE, "02/03/00"), },
2160 { /* Handle problems with APM on Sony Vaio PCG-XG29 */
2161 swab_apm_power_in_minutes, "Sony VAIO",
2162 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2163 DMI_MATCH(DMI_BIOS_VERSION, "R0117A0"),
2164 DMI_MATCH(DMI_BIOS_DATE, "04/25/00"), },
2166 { /* Handle problems with APM on Sony Vaio PCG-Z600NE */
2167 swab_apm_power_in_minutes, "Sony VAIO",
2168 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2169 DMI_MATCH(DMI_BIOS_VERSION, "R0121Z1"),
2170 DMI_MATCH(DMI_BIOS_DATE, "05/11/00"), },
2172 { /* Handle problems with APM on Sony Vaio PCG-Z600NE */
2173 swab_apm_power_in_minutes, "Sony VAIO",
2174 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2175 DMI_MATCH(DMI_BIOS_VERSION, "WME01Z1"),
2176 DMI_MATCH(DMI_BIOS_DATE, "08/11/00"), },
2178 { /* Handle problems with APM on Sony Vaio PCG-Z600LEK(DE) */
2179 swab_apm_power_in_minutes, "Sony VAIO",
2180 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2181 DMI_MATCH(DMI_BIOS_VERSION, "R0206Z3"),
2182 DMI_MATCH(DMI_BIOS_DATE, "12/25/00"), },
2184 { /* Handle problems with APM on Sony Vaio PCG-Z505LS */
2185 swab_apm_power_in_minutes, "Sony VAIO",
2186 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2187 DMI_MATCH(DMI_BIOS_VERSION, "R0203D0"),
2188 DMI_MATCH(DMI_BIOS_DATE, "05/12/00"), },
2190 { /* Handle problems with APM on Sony Vaio PCG-Z505LS */
2191 swab_apm_power_in_minutes, "Sony VAIO",
2192 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2193 DMI_MATCH(DMI_BIOS_VERSION, "R0203Z3"),
2194 DMI_MATCH(DMI_BIOS_DATE, "08/25/00"), },
2196 { /* Handle problems with APM on Sony Vaio PCG-Z505LS (with updated BIOS) */
2197 swab_apm_power_in_minutes, "Sony VAIO",
2198 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2199 DMI_MATCH(DMI_BIOS_VERSION, "R0209Z3"),
2200 DMI_MATCH(DMI_BIOS_DATE, "05/12/01"), },
2202 { /* Handle problems with APM on Sony Vaio PCG-F104K */
2203 swab_apm_power_in_minutes, "Sony VAIO",
2204 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2205 DMI_MATCH(DMI_BIOS_VERSION, "R0204K2"),
2206 DMI_MATCH(DMI_BIOS_DATE, "08/28/00"), },
2209 { /* Handle problems with APM on Sony Vaio PCG-C1VN/C1VE */
2210 swab_apm_power_in_minutes, "Sony VAIO",
2211 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2212 DMI_MATCH(DMI_BIOS_VERSION, "R0208P1"),
2213 DMI_MATCH(DMI_BIOS_DATE, "11/09/00"), },
2215 { /* Handle problems with APM on Sony Vaio PCG-C1VE */
2216 swab_apm_power_in_minutes, "Sony VAIO",
2217 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2218 DMI_MATCH(DMI_BIOS_VERSION, "R0204P1"),
2219 DMI_MATCH(DMI_BIOS_DATE, "09/12/00"), },
2221 { /* Handle problems with APM on Sony Vaio PCG-C1VE */
2222 swab_apm_power_in_minutes, "Sony VAIO",
2223 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2224 DMI_MATCH(DMI_BIOS_VERSION, "WXPO1Z3"),
2225 DMI_MATCH(DMI_BIOS_DATE, "10/26/01"), },
2227 { /* broken PM poweroff bios */
2228 set_realmode_power_off, "Award Software v4.60 PGMA",
2229 { DMI_MATCH(DMI_BIOS_VENDOR, "Award Software International, Inc."),
2230 DMI_MATCH(DMI_BIOS_VERSION, "4.60 PGMA"),
2231 DMI_MATCH(DMI_BIOS_DATE, "134526184"), },
2234 /* Generic per vendor APM settings */
2236 { /* Allow interrupts during suspend on IBM laptops */
2237 set_apm_ints, "IBM",
2238 { DMI_MATCH(DMI_SYS_VENDOR, "IBM"), },
2245 * Just start the APM thread. We do NOT want to do APM BIOS
2246 * calls from anything but the APM thread, if for no other reason
2247 * than the fact that we don't trust the APM BIOS. This way,
2248 * most common APM BIOS problems that lead to protection errors
2249 * etc will have at least some level of being contained...
2251 * In short, if something bad happens, at least we have a choice
2252 * of just killing the apm thread..
2254 static int __init apm_init(void)
2256 struct desc_struct *gdt;
2259 dmi_check_system(apm_dmi_table);
2261 if (apm_info.bios.version == 0 || machine_is_olpc()) {
2262 printk(KERN_INFO "apm: BIOS not found.\n");
2266 "apm: BIOS version %d.%d Flags 0x%02x (Driver version %s)\n",
2267 ((apm_info.bios.version >> 8) & 0xff),
2268 (apm_info.bios.version & 0xff),
2269 apm_info.bios.flags,
2271 if ((apm_info.bios.flags & APM_32_BIT_SUPPORT) == 0) {
2272 printk(KERN_INFO "apm: no 32 bit BIOS support\n");
2277 apm_info.allow_ints = 1;
2279 apm_info.get_power_status_broken = 1;
2280 if (realmode_power_off)
2281 apm_info.realmode_power_off = 1;
2282 /* User can override, but default is to trust DMI */
2283 if (apm_disabled != -1)
2284 apm_info.disabled = apm_disabled;
2287 * Fix for the Compaq Contura 3/25c which reports BIOS version 0.1
2288 * but is reportedly a 1.0 BIOS.
2290 if (apm_info.bios.version == 0x001)
2291 apm_info.bios.version = 0x100;
2293 /* BIOS < 1.2 doesn't set cseg_16_len */
2294 if (apm_info.bios.version < 0x102)
2295 apm_info.bios.cseg_16_len = 0; /* 64k */
2298 printk(KERN_INFO "apm: entry %x:%x cseg16 %x dseg %x",
2299 apm_info.bios.cseg, apm_info.bios.offset,
2300 apm_info.bios.cseg_16, apm_info.bios.dseg);
2301 if (apm_info.bios.version > 0x100)
2302 printk(" cseg len %x, dseg len %x",
2303 apm_info.bios.cseg_len,
2304 apm_info.bios.dseg_len);
2305 if (apm_info.bios.version > 0x101)
2306 printk(" cseg16 len %x", apm_info.bios.cseg_16_len);
2310 if (apm_info.disabled) {
2311 pr_notice("disabled on user request.\n");
2314 if ((num_online_cpus() > 1) && !power_off && !smp) {
2315 pr_notice("disabled - APM is not SMP safe.\n");
2316 apm_info.disabled = 1;
2319 if (!acpi_disabled) {
2320 pr_notice("overridden by ACPI.\n");
2321 apm_info.disabled = 1;
2326 * Set up the long jump entry point to the APM BIOS, which is called
2327 * from inline assembly.
2329 apm_bios_entry.offset = apm_info.bios.offset;
2330 apm_bios_entry.segment = APM_CS;
2333 * The APM 1.1 BIOS is supposed to provide limit information that it
2334 * recognizes. Many machines do this correctly, but many others do
2335 * not restrict themselves to their claimed limit. When this happens,
2336 * they will cause a segmentation violation in the kernel at boot time.
2337 * Most BIOS's, however, will respect a 64k limit, so we use that.
2339 * Note we only set APM segments on CPU zero, since we pin the APM
2342 gdt = get_cpu_gdt_rw(0);
2343 set_desc_base(&gdt[APM_CS >> 3],
2344 (unsigned long)__va((unsigned long)apm_info.bios.cseg << 4));
2345 set_desc_base(&gdt[APM_CS_16 >> 3],
2346 (unsigned long)__va((unsigned long)apm_info.bios.cseg_16 << 4));
2347 set_desc_base(&gdt[APM_DS >> 3],
2348 (unsigned long)__va((unsigned long)apm_info.bios.dseg << 4));
2350 proc_create_single("apm", 0, NULL, proc_apm_show);
2352 kapmd_task = kthread_create(apm, NULL, "kapmd");
2353 if (IS_ERR(kapmd_task)) {
2354 pr_err("disabled - Unable to start kernel thread\n");
2355 err = PTR_ERR(kapmd_task);
2357 remove_proc_entry("apm", NULL);
2360 wake_up_process(kapmd_task);
2362 if (num_online_cpus() > 1 && !smp) {
2364 "apm: disabled - APM is not SMP safe (power off active).\n");
2369 * Note we don't actually care if the misc_device cannot be registered.
2370 * this driver can do its job without it, even if userspace can't
2371 * control it. just log the error
2373 if (misc_register(&apm_device))
2374 printk(KERN_WARNING "apm: Could not register misc device.\n");
2377 idle_period = (idle_period * HZ) / 100;
2378 if (idle_threshold < 100) {
2379 cpuidle_poll_state_init(&apm_idle_driver);
2380 if (!cpuidle_register_driver(&apm_idle_driver))
2381 if (cpuidle_register_device(&apm_cpuidle_device))
2382 cpuidle_unregister_driver(&apm_idle_driver);
2388 static void __exit apm_exit(void)
2392 cpuidle_unregister_device(&apm_cpuidle_device);
2393 cpuidle_unregister_driver(&apm_idle_driver);
2395 if (((apm_info.bios.flags & APM_BIOS_DISENGAGED) == 0)
2396 && (apm_info.connection_version > 0x0100)) {
2397 error = apm_engage_power_management(APM_DEVICE_ALL, 0);
2399 apm_error("disengage power management", error);
2401 misc_deregister(&apm_device);
2402 remove_proc_entry("apm", NULL);
2404 pm_power_off = NULL;
2406 kthread_stop(kapmd_task);
2411 module_init(apm_init);
2412 module_exit(apm_exit);
2414 MODULE_AUTHOR("Stephen Rothwell");
2415 MODULE_DESCRIPTION("Advanced Power Management");
2416 MODULE_LICENSE("GPL");
2417 module_param(debug, bool, 0644);
2418 MODULE_PARM_DESC(debug, "Enable debug mode");
2419 module_param(power_off, bool, 0444);
2420 MODULE_PARM_DESC(power_off, "Enable power off");
2421 module_param(bounce_interval, int, 0444);
2422 MODULE_PARM_DESC(bounce_interval,
2423 "Set the number of ticks to ignore suspend bounces");
2424 module_param(allow_ints, bool, 0444);
2425 MODULE_PARM_DESC(allow_ints, "Allow interrupts during BIOS calls");
2426 module_param(broken_psr, bool, 0444);
2427 MODULE_PARM_DESC(broken_psr, "BIOS has a broken GetPowerStatus call");
2428 module_param(realmode_power_off, bool, 0444);
2429 MODULE_PARM_DESC(realmode_power_off,
2430 "Switch to real mode before powering off");
2431 module_param(idle_threshold, int, 0444);
2432 MODULE_PARM_DESC(idle_threshold,
2433 "System idle percentage above which to make APM BIOS idle calls");
2434 module_param(idle_period, int, 0444);
2435 MODULE_PARM_DESC(idle_period,
2436 "Period (in sec/100) over which to calculate the idle percentage");
2437 module_param(smp, bool, 0444);
2438 MODULE_PARM_DESC(smp,
2439 "Set this to enable APM use on an SMP platform. Use with caution on older systems");
2440 MODULE_ALIAS_MISCDEV(APM_MINOR_DEV);