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>
243 #include <asm/nospec-branch.h>
245 #if defined(CONFIG_APM_DISPLAY_BLANK) && defined(CONFIG_VT)
246 extern int (*console_blank_hook
)(int);
250 * The apm_bios device is one of the misc char devices.
251 * This is its minor number.
253 #define APM_MINOR_DEV 134
256 * Various options can be changed at boot time as follows:
257 * (We allow underscores for compatibility with the modules code)
258 * apm=on/off enable/disable APM
259 * [no-]allow[-_]ints allow interrupts during BIOS calls
260 * [no-]broken[-_]psr BIOS has a broken GetPowerStatus call
261 * [no-]realmode[-_]power[-_]off switch to real mode before
263 * [no-]debug log some debugging messages
264 * [no-]power[-_]off power off on shutdown
265 * [no-]smp Use apm even on an SMP box
266 * bounce[-_]interval=<n> number of ticks to ignore suspend
268 * idle[-_]threshold=<n> System idle percentage above which to
269 * make APM BIOS idle calls. Set it to
271 * idle[-_]period=<n> Period (in 1/100s of a second) over
272 * which the idle percentage is
276 /* KNOWN PROBLEM MACHINES:
278 * U: TI 4000M TravelMate: BIOS is *NOT* APM compliant
279 * [Confirmed by TI representative]
280 * ?: ACER 486DX4/75: uses dseg 0040, in violation of APM specification
281 * [Confirmed by BIOS disassembly]
282 * [This may work now ...]
283 * P: Toshiba 1950S: battery life information only gets updated after resume
284 * P: Midwest Micro Soundbook Elite DX2/66 monochrome: screen blanking
285 * broken in BIOS [Reported by Garst R. Reese <reese@isn.net>]
286 * ?: AcerNote-950: oops on reading /proc/apm - workaround is a WIP
287 * Neale Banks <neale@lowendale.com.au> December 2000
289 * Legend: U = unusable with APM patches
290 * P = partially usable with APM patches
294 * Define as 1 to make the driver always call the APM BIOS busy
295 * routine even if the clock was not reported as slowed by the
296 * idle routine. Otherwise, define as 0.
298 #define ALWAYS_CALL_BUSY 1
301 * Define to make the APM BIOS calls zero all data segment registers (so
302 * that an incorrect BIOS implementation will cause a kernel panic if it
303 * tries to write to arbitrary memory).
305 #define APM_ZERO_SEGS
310 * Define to re-initialize the interrupt 0 timer to 100 Hz after a suspend.
311 * This patched by Chad Miller <cmiller@surfsouth.com>, original code by
312 * David Chen <chen@ctpa04.mit.edu>
314 #undef INIT_TIMER_AFTER_SUSPEND
316 #ifdef INIT_TIMER_AFTER_SUSPEND
317 #include <linux/timex.h>
319 #include <linux/delay.h>
323 * Need to poll the APM BIOS every second
325 #define APM_CHECK_TIMEOUT (HZ)
328 * Ignore suspend events for this amount of time after a resume
330 #define DEFAULT_BOUNCE_INTERVAL (3 * HZ)
333 * Maximum number of events stored
335 #define APM_MAX_EVENTS 20
338 * The per-file APM data
342 struct apm_user
*next
;
343 unsigned int suser
: 1;
344 unsigned int writer
: 1;
345 unsigned int reader
: 1;
346 unsigned int suspend_wait
: 1;
348 int suspends_pending
;
349 int standbys_pending
;
354 apm_event_t events
[APM_MAX_EVENTS
];
358 * The magic number in apm_user
360 #define APM_BIOS_MAGIC 0x4101
363 * idle percentage above which bios idle calls are done
365 #ifdef CONFIG_APM_CPU_IDLE
366 #define DEFAULT_IDLE_THRESHOLD 95
368 #define DEFAULT_IDLE_THRESHOLD 100
370 #define DEFAULT_IDLE_PERIOD (100 / 3)
372 static int apm_cpu_idle(struct cpuidle_device
*dev
,
373 struct cpuidle_driver
*drv
, int index
);
375 static struct cpuidle_driver apm_idle_driver
= {
377 .owner
= THIS_MODULE
,
379 { /* entry 0 is for polling */ },
380 { /* entry 1 is for APM idle */
383 .exit_latency
= 250, /* WAG */
384 .target_residency
= 500, /* WAG */
385 .enter
= &apm_cpu_idle
391 static struct cpuidle_device apm_cpuidle_device
;
397 unsigned long offset
;
398 unsigned short segment
;
400 static int clock_slowed
;
401 static int idle_threshold __read_mostly
= DEFAULT_IDLE_THRESHOLD
;
402 static int idle_period __read_mostly
= DEFAULT_IDLE_PERIOD
;
403 static int suspends_pending
;
404 static int standbys_pending
;
405 static int ignore_sys_suspend
;
406 static int ignore_normal_resume
;
407 static int bounce_interval __read_mostly
= DEFAULT_BOUNCE_INTERVAL
;
409 static bool debug __read_mostly
;
410 static bool smp __read_mostly
;
411 static int apm_disabled
= -1;
413 static bool power_off
;
415 static bool power_off
= 1;
417 static bool realmode_power_off
;
418 #ifdef CONFIG_APM_ALLOW_INTS
419 static bool allow_ints
= 1;
421 static bool allow_ints
;
423 static bool broken_psr
;
425 static DECLARE_WAIT_QUEUE_HEAD(apm_waitqueue
);
426 static DECLARE_WAIT_QUEUE_HEAD(apm_suspend_waitqueue
);
427 static struct apm_user
*user_list
;
428 static DEFINE_SPINLOCK(user_list_lock
);
429 static DEFINE_MUTEX(apm_mutex
);
432 * Set up a segment that references the real mode segment 0x40
433 * that extends up to the end of page zero (that we have reserved).
434 * This is for buggy BIOS's that refer to (real mode) segment 0x40
435 * even though they are called in protected mode.
437 static struct desc_struct bad_bios_desc
= GDT_ENTRY_INIT(0x4092,
438 (unsigned long)__va(0x400UL
), PAGE_SIZE
- 0x400 - 1);
440 static const char driver_version
[] = "1.16ac"; /* no spaces */
442 static struct task_struct
*kapmd_task
;
445 * APM event names taken from the APM 1.2 specification. These are
446 * the message codes that the BIOS uses to tell us about events
448 static const char * const apm_event_name
[] = {
454 "power status change",
459 "system standby resume",
460 "capabilities change"
462 #define NR_APM_EVENT_NAME ARRAY_SIZE(apm_event_name)
464 typedef struct lookup_t
{
470 * The BIOS returns a set of standard error codes in AX when the
474 static const lookup_t error_table
[] = {
475 /* N/A { APM_SUCCESS, "Operation succeeded" }, */
476 { APM_DISABLED
, "Power management disabled" },
477 { APM_CONNECTED
, "Real mode interface already connected" },
478 { APM_NOT_CONNECTED
, "Interface not connected" },
479 { APM_16_CONNECTED
, "16 bit interface already connected" },
480 /* N/A { APM_16_UNSUPPORTED, "16 bit interface not supported" }, */
481 { APM_32_CONNECTED
, "32 bit interface already connected" },
482 { APM_32_UNSUPPORTED
, "32 bit interface not supported" },
483 { APM_BAD_DEVICE
, "Unrecognized device ID" },
484 { APM_BAD_PARAM
, "Parameter out of range" },
485 { APM_NOT_ENGAGED
, "Interface not engaged" },
486 { APM_BAD_FUNCTION
, "Function not supported" },
487 { APM_RESUME_DISABLED
, "Resume timer disabled" },
488 { APM_BAD_STATE
, "Unable to enter requested state" },
489 /* N/A { APM_NO_EVENTS, "No events pending" }, */
490 { APM_NO_ERROR
, "BIOS did not set a return code" },
491 { APM_NOT_PRESENT
, "No APM present" }
493 #define ERROR_COUNT ARRAY_SIZE(error_table)
496 * apm_error - display an APM error
497 * @str: information string
498 * @err: APM BIOS return code
500 * Write a meaningful log entry to the kernel log in the event of
501 * an APM error. Note that this also handles (negative) kernel errors.
504 static void apm_error(char *str
, int err
)
508 for (i
= 0; i
< ERROR_COUNT
; i
++)
509 if (error_table
[i
].key
== err
)
512 pr_notice("%s: %s\n", str
, error_table
[i
].msg
);
514 pr_notice("%s: linux error code %i\n", str
, err
);
516 pr_notice("%s: unknown error code %#2.2x\n",
521 * These are the actual BIOS calls. Depending on APM_ZERO_SEGS and
522 * apm_info.allow_ints, we are being really paranoid here! Not only
523 * are interrupts disabled, but all the segment registers (except SS)
524 * are saved and zeroed this means that if the BIOS tries to reference
525 * any data without explicitly loading the segment registers, the kernel
526 * will fault immediately rather than have some unforeseen circumstances
527 * for the rest of the kernel. And it will be very obvious! :-) Doing
528 * this depends on CS referring to the same physical memory as DS so that
529 * DS can be zeroed before the call. Unfortunately, we can't do anything
530 * about the stack segment/pointer. Also, we tell the compiler that
531 * everything could change.
533 * Also, we KNOW that for the non error case of apm_bios_call, there
534 * is no useful data returned in the low order 8 bits of eax.
537 static inline unsigned long __apm_irq_save(void)
540 local_save_flags(flags
);
541 if (apm_info
.allow_ints
) {
542 if (irqs_disabled_flags(flags
))
550 #define apm_irq_save(flags) \
551 do { flags = __apm_irq_save(); } while (0)
553 static inline void apm_irq_restore(unsigned long flags
)
555 if (irqs_disabled_flags(flags
))
557 else if (irqs_disabled())
562 # define APM_DECL_SEGS \
563 unsigned int saved_fs; unsigned int saved_gs;
564 # define APM_DO_SAVE_SEGS \
565 savesegment(fs, saved_fs); savesegment(gs, saved_gs)
566 # define APM_DO_RESTORE_SEGS \
567 loadsegment(fs, saved_fs); loadsegment(gs, saved_gs)
569 # define APM_DECL_SEGS
570 # define APM_DO_SAVE_SEGS
571 # define APM_DO_RESTORE_SEGS
574 struct apm_bios_call
{
584 /* Error: -ENOMEM, or bits 8-15 of eax */
589 * __apm_bios_call - Make an APM BIOS 32bit call
590 * @_call: pointer to struct apm_bios_call.
592 * Make an APM call using the 32bit protected mode interface. The
593 * caller is responsible for knowing if APM BIOS is configured and
594 * enabled. This call can disable interrupts for a long period of
595 * time on some laptops. The return value is in AH and the carry
596 * flag is loaded into AL. If there is an error, then the error
597 * code is returned in AH (bits 8-15 of eax) and this function
600 * Note: this makes the call on the current CPU.
602 static long __apm_bios_call(void *_call
)
607 struct desc_struct save_desc_40
;
608 struct desc_struct
*gdt
;
609 struct apm_bios_call
*call
= _call
;
613 gdt
= get_cpu_gdt_rw(cpu
);
614 save_desc_40
= gdt
[0x40 / 8];
615 gdt
[0x40 / 8] = bad_bios_desc
;
618 firmware_restrict_branch_speculation_start();
620 apm_bios_call_asm(call
->func
, call
->ebx
, call
->ecx
,
621 &call
->eax
, &call
->ebx
, &call
->ecx
, &call
->edx
,
624 firmware_restrict_branch_speculation_end();
625 apm_irq_restore(flags
);
626 gdt
[0x40 / 8] = save_desc_40
;
629 return call
->eax
& 0xff;
632 /* Run __apm_bios_call or __apm_bios_call_simple on CPU 0 */
633 static int on_cpu0(long (*fn
)(void *), struct apm_bios_call
*call
)
637 /* Don't bother with work_on_cpu in the common case, so we don't
638 * have to worry about OOM or overhead. */
639 if (get_cpu() == 0) {
644 ret
= work_on_cpu(0, fn
, call
);
647 /* work_on_cpu can fail with -ENOMEM */
651 call
->err
= (call
->eax
>> 8) & 0xff;
657 * apm_bios_call - Make an APM BIOS 32bit call (on CPU 0)
658 * @call: the apm_bios_call registers.
660 * If there is an error, it is returned in @call.err.
662 static int apm_bios_call(struct apm_bios_call
*call
)
664 return on_cpu0(__apm_bios_call
, call
);
668 * __apm_bios_call_simple - Make an APM BIOS 32bit call (on CPU 0)
669 * @_call: pointer to struct apm_bios_call.
671 * Make a BIOS call that returns one value only, or just status.
672 * If there is an error, then the error code is returned in AH
673 * (bits 8-15 of eax) and this function returns non-zero (it can
674 * also return -ENOMEM). This is used for simpler BIOS operations.
675 * This call may hold interrupts off for a long time on some laptops.
677 * Note: this makes the call on the current CPU.
679 static long __apm_bios_call_simple(void *_call
)
685 struct desc_struct save_desc_40
;
686 struct desc_struct
*gdt
;
687 struct apm_bios_call
*call
= _call
;
691 gdt
= get_cpu_gdt_rw(cpu
);
692 save_desc_40
= gdt
[0x40 / 8];
693 gdt
[0x40 / 8] = bad_bios_desc
;
696 firmware_restrict_branch_speculation_start();
698 error
= apm_bios_call_simple_asm(call
->func
, call
->ebx
, call
->ecx
,
701 firmware_restrict_branch_speculation_end();
702 apm_irq_restore(flags
);
703 gdt
[0x40 / 8] = save_desc_40
;
709 * apm_bios_call_simple - make a simple APM BIOS 32bit call
710 * @func: APM function to invoke
711 * @ebx_in: EBX register value for BIOS call
712 * @ecx_in: ECX register value for BIOS call
713 * @eax: EAX register on return from the BIOS call
716 * Make a BIOS call that returns one value only, or just status.
717 * If there is an error, then the error code is returned in @err
718 * and this function returns non-zero. This is used for simpler
719 * BIOS operations. This call may hold interrupts off for a long
720 * time on some laptops.
722 static int apm_bios_call_simple(u32 func
, u32 ebx_in
, u32 ecx_in
, u32
*eax
,
725 struct apm_bios_call call
;
732 ret
= on_cpu0(__apm_bios_call_simple
, &call
);
739 * apm_driver_version - APM driver version
740 * @val: loaded with the APM version on return
742 * Retrieve the APM version supported by the BIOS. This is only
743 * supported for APM 1.1 or higher. An error indicates APM 1.0 is
746 * On entry val should point to a value indicating the APM driver
747 * version with the high byte being the major and the low byte the
748 * minor number both in BCD
750 * On return it will hold the BIOS revision supported in the
754 static int apm_driver_version(u_short
*val
)
759 if (apm_bios_call_simple(APM_FUNC_VERSION
, 0, *val
, &eax
, &err
))
766 * apm_get_event - get an APM event from the BIOS
767 * @event: pointer to the event
768 * @info: point to the event information
770 * The APM BIOS provides a polled information for event
771 * reporting. The BIOS expects to be polled at least every second
772 * when events are pending. When a message is found the caller should
773 * poll until no more messages are present. However, this causes
774 * problems on some laptops where a suspend event notification is
775 * not cleared until it is acknowledged.
777 * Additional information is returned in the info pointer, providing
778 * that APM 1.2 is in use. If no messges are pending the value 0x80
779 * is returned (No power management events pending).
781 static int apm_get_event(apm_event_t
*event
, apm_eventinfo_t
*info
)
783 struct apm_bios_call call
;
785 call
.func
= APM_FUNC_GET_EVENT
;
786 call
.ebx
= call
.ecx
= 0;
788 if (apm_bios_call(&call
))
792 if (apm_info
.connection_version
< 0x0102)
793 *info
= ~0; /* indicate info not valid */
800 * set_power_state - set the power management state
801 * @what: which items to transition
802 * @state: state to transition to
804 * Request an APM change of state for one or more system devices. The
805 * processor state must be transitioned last of all. what holds the
806 * class of device in the upper byte and the device number (0xFF for
807 * all) for the object to be transitioned.
809 * The state holds the state to transition to, which may in fact
810 * be an acceptance of a BIOS requested state change.
813 static int set_power_state(u_short what
, u_short state
)
818 if (apm_bios_call_simple(APM_FUNC_SET_STATE
, what
, state
, &eax
, &err
))
824 * set_system_power_state - set system wide power state
825 * @state: which state to enter
827 * Transition the entire system into a new APM power state.
830 static int set_system_power_state(u_short state
)
832 return set_power_state(APM_DEVICE_ALL
, state
);
836 * apm_do_idle - perform power saving
838 * This function notifies the BIOS that the processor is (in the view
839 * of the OS) idle. It returns -1 in the event that the BIOS refuses
840 * to handle the idle request. On a success the function returns 1
841 * if the BIOS did clock slowing or 0 otherwise.
844 static int apm_do_idle(void)
851 if (!need_resched()) {
853 ret
= apm_bios_call_simple(APM_FUNC_IDLE
, 0, 0, &eax
, &err
);
860 static unsigned long t
;
862 /* This always fails on some SMP boards running UP kernels.
863 * Only report the failure the first 5 times.
866 printk(KERN_DEBUG
"apm_do_idle failed (%d)\n", err
);
871 clock_slowed
= (apm_info
.bios
.flags
& APM_IDLE_SLOWS_CLOCK
) != 0;
876 * apm_do_busy - inform the BIOS the CPU is busy
878 * Request that the BIOS brings the CPU back to full performance.
881 static void apm_do_busy(void)
886 if (clock_slowed
|| ALWAYS_CALL_BUSY
) {
887 (void)apm_bios_call_simple(APM_FUNC_BUSY
, 0, 0, &dummy
, &err
);
893 * If no process has really been interested in
894 * the CPU for some time, we want to call BIOS
895 * power management - we probably want
898 #define IDLE_CALC_LIMIT (HZ * 100)
899 #define IDLE_LEAKY_MAX 16
902 * apm_cpu_idle - cpu idling for APM capable Linux
904 * This is the idling function the kernel executes when APM is available. It
905 * tries to do BIOS powermanagement based on the average system idle time.
906 * Furthermore it calls the system default idle routine.
909 static int apm_cpu_idle(struct cpuidle_device
*dev
,
910 struct cpuidle_driver
*drv
, int index
)
912 static int use_apm_idle
; /* = 0 */
913 static unsigned int last_jiffies
; /* = 0 */
914 static u64 last_stime
; /* = 0 */
917 int apm_idle_done
= 0;
918 unsigned int jiffies_since_last_check
= jiffies
- last_jiffies
;
922 task_cputime(current
, &utime
, &stime
);
923 if (jiffies_since_last_check
> IDLE_CALC_LIMIT
) {
925 } else if (jiffies_since_last_check
> idle_period
) {
926 unsigned int idle_percentage
;
928 idle_percentage
= nsecs_to_jiffies(stime
- last_stime
);
929 idle_percentage
*= 100;
930 idle_percentage
/= jiffies_since_last_check
;
931 use_apm_idle
= (idle_percentage
> idle_threshold
);
932 if (apm_info
.forbid_idle
)
936 last_jiffies
= jiffies
;
939 bucket
= IDLE_LEAKY_MAX
;
941 while (!need_resched()) {
946 switch (apm_do_idle()) {
951 bucket
= IDLE_LEAKY_MAX
;
962 default: /* BIOS refused */
968 jiffies_since_last_check
= jiffies
- last_jiffies
;
969 if (jiffies_since_last_check
> idle_period
)
980 * apm_power_off - ask the BIOS to power off
982 * Handle the power off sequence. This is the one piece of code we
983 * will execute even on SMP machines. In order to deal with BIOS
984 * bugs we support real mode APM BIOS power off calls. We also make
985 * the SMP call on CPU0 as some systems will only honour this call
986 * on their first cpu.
989 static void apm_power_off(void)
991 /* Some bioses don't like being called from CPU != 0 */
992 if (apm_info
.realmode_power_off
) {
993 set_cpus_allowed_ptr(current
, cpumask_of(0));
994 machine_real_restart(MRR_APM
);
996 (void)set_system_power_state(APM_STATE_OFF
);
1000 #ifdef CONFIG_APM_DO_ENABLE
1003 * apm_enable_power_management - enable BIOS APM power management
1004 * @enable: enable yes/no
1006 * Enable or disable the APM BIOS power services.
1009 static int apm_enable_power_management(int enable
)
1014 if ((enable
== 0) && (apm_info
.bios
.flags
& APM_BIOS_DISENGAGED
))
1015 return APM_NOT_ENGAGED
;
1016 if (apm_bios_call_simple(APM_FUNC_ENABLE_PM
, APM_DEVICE_BALL
,
1017 enable
, &eax
, &err
))
1020 apm_info
.bios
.flags
&= ~APM_BIOS_DISABLED
;
1022 apm_info
.bios
.flags
|= APM_BIOS_DISABLED
;
1028 * apm_get_power_status - get current power state
1029 * @status: returned status
1030 * @bat: battery info
1031 * @life: estimated life
1033 * Obtain the current power status from the APM BIOS. We return a
1034 * status which gives the rough battery status, and current power
1035 * source. The bat value returned give an estimate as a percentage
1036 * of life and a status value for the battery. The estimated life
1037 * if reported is a lifetime in secodnds/minutes at current powwer
1041 static int apm_get_power_status(u_short
*status
, u_short
*bat
, u_short
*life
)
1043 struct apm_bios_call call
;
1045 call
.func
= APM_FUNC_GET_STATUS
;
1046 call
.ebx
= APM_DEVICE_ALL
;
1049 if (apm_info
.get_power_status_broken
)
1050 return APM_32_UNSUPPORTED
;
1051 if (apm_bios_call(&call
)) {
1053 return APM_NO_ERROR
;
1058 if (apm_info
.get_power_status_swabinminutes
) {
1059 *life
= swab16((u16
)call
.edx
);
1067 static int apm_get_battery_status(u_short which
, u_short
*status
,
1068 u_short
*bat
, u_short
*life
, u_short
*nbat
)
1076 if (apm_info
.connection_version
< 0x0102) {
1077 /* pretend we only have one battery. */
1079 return APM_BAD_DEVICE
;
1081 return apm_get_power_status(status
, bat
, life
);
1084 if (apm_bios_call(APM_FUNC_GET_STATUS
, (0x8000 | (which
)), 0, &eax
,
1085 &ebx
, &ecx
, &edx
, &esi
))
1086 return (eax
>> 8) & 0xff;
1096 * apm_engage_power_management - enable PM on a device
1097 * @device: identity of device
1100 * Activate or deactivate power management on either a specific device
1101 * or the entire system (%APM_DEVICE_ALL).
1104 static int apm_engage_power_management(u_short device
, int enable
)
1109 if ((enable
== 0) && (device
== APM_DEVICE_ALL
)
1110 && (apm_info
.bios
.flags
& APM_BIOS_DISABLED
))
1111 return APM_DISABLED
;
1112 if (apm_bios_call_simple(APM_FUNC_ENGAGE_PM
, device
, enable
,
1115 if (device
== APM_DEVICE_ALL
) {
1117 apm_info
.bios
.flags
&= ~APM_BIOS_DISENGAGED
;
1119 apm_info
.bios
.flags
|= APM_BIOS_DISENGAGED
;
1124 #if defined(CONFIG_APM_DISPLAY_BLANK) && defined(CONFIG_VT)
1127 * apm_console_blank - blank the display
1130 * Attempt to blank the console, firstly by blanking just video device
1131 * zero, and if that fails (some BIOSes don't support it) then it blanks
1132 * all video devices. Typically the BIOS will do laptop backlight and
1133 * monitor powerdown for us.
1136 static int apm_console_blank(int blank
)
1138 int error
= APM_NOT_ENGAGED
; /* silence gcc */
1141 static const u_short dev
[3] = { 0x100, 0x1FF, 0x101 };
1143 state
= blank
? APM_STATE_STANDBY
: APM_STATE_READY
;
1145 for (i
= 0; i
< ARRAY_SIZE(dev
); i
++) {
1146 error
= set_power_state(dev
[i
], state
);
1148 if ((error
== APM_SUCCESS
) || (error
== APM_NO_ERROR
))
1151 if (error
== APM_NOT_ENGAGED
)
1155 if (error
== APM_NOT_ENGAGED
) {
1159 eng_error
= apm_engage_power_management(APM_DEVICE_ALL
, 1);
1161 apm_error("set display", error
);
1162 apm_error("engage interface", eng_error
);
1165 return apm_console_blank(blank
);
1168 apm_error("set display", error
);
1173 static int queue_empty(struct apm_user
*as
)
1175 return as
->event_head
== as
->event_tail
;
1178 static apm_event_t
get_queued_event(struct apm_user
*as
)
1180 if (++as
->event_tail
>= APM_MAX_EVENTS
)
1182 return as
->events
[as
->event_tail
];
1185 static void queue_event(apm_event_t event
, struct apm_user
*sender
)
1187 struct apm_user
*as
;
1189 spin_lock(&user_list_lock
);
1190 if (user_list
== NULL
)
1192 for (as
= user_list
; as
!= NULL
; as
= as
->next
) {
1193 if ((as
== sender
) || (!as
->reader
))
1195 if (++as
->event_head
>= APM_MAX_EVENTS
)
1198 if (as
->event_head
== as
->event_tail
) {
1199 static int notified
;
1201 if (notified
++ == 0)
1202 pr_err("an event queue overflowed\n");
1203 if (++as
->event_tail
>= APM_MAX_EVENTS
)
1206 as
->events
[as
->event_head
] = event
;
1207 if (!as
->suser
|| !as
->writer
)
1210 case APM_SYS_SUSPEND
:
1211 case APM_USER_SUSPEND
:
1212 as
->suspends_pending
++;
1216 case APM_SYS_STANDBY
:
1217 case APM_USER_STANDBY
:
1218 as
->standbys_pending
++;
1223 wake_up_interruptible(&apm_waitqueue
);
1225 spin_unlock(&user_list_lock
);
1228 static void reinit_timer(void)
1230 #ifdef INIT_TIMER_AFTER_SUSPEND
1231 unsigned long flags
;
1233 raw_spin_lock_irqsave(&i8253_lock
, flags
);
1234 /* set the clock to HZ */
1235 outb_p(0x34, PIT_MODE
); /* binary, mode 2, LSB/MSB, ch 0 */
1237 outb_p(LATCH
& 0xff, PIT_CH0
); /* LSB */
1239 outb_p(LATCH
>> 8, PIT_CH0
); /* MSB */
1241 raw_spin_unlock_irqrestore(&i8253_lock
, flags
);
1245 static int suspend(int vetoable
)
1248 struct apm_user
*as
;
1250 dpm_suspend_start(PMSG_SUSPEND
);
1251 dpm_suspend_end(PMSG_SUSPEND
);
1253 local_irq_disable();
1258 save_processor_state();
1259 err
= set_system_power_state(APM_STATE_SUSPEND
);
1260 ignore_normal_resume
= 1;
1261 restore_processor_state();
1263 local_irq_disable();
1266 if (err
== APM_NO_ERROR
)
1268 if (err
!= APM_SUCCESS
)
1269 apm_error("suspend", err
);
1270 err
= (err
== APM_SUCCESS
) ? 0 : -EIO
;
1275 dpm_resume_start(PMSG_RESUME
);
1276 dpm_resume_end(PMSG_RESUME
);
1278 queue_event(APM_NORMAL_RESUME
, NULL
);
1279 spin_lock(&user_list_lock
);
1280 for (as
= user_list
; as
!= NULL
; as
= as
->next
) {
1281 as
->suspend_wait
= 0;
1282 as
->suspend_result
= err
;
1284 spin_unlock(&user_list_lock
);
1285 wake_up_interruptible(&apm_suspend_waitqueue
);
1289 static void standby(void)
1293 dpm_suspend_end(PMSG_SUSPEND
);
1295 local_irq_disable();
1299 err
= set_system_power_state(APM_STATE_STANDBY
);
1300 if ((err
!= APM_SUCCESS
) && (err
!= APM_NO_ERROR
))
1301 apm_error("standby", err
);
1303 local_irq_disable();
1307 dpm_resume_start(PMSG_RESUME
);
1310 static apm_event_t
get_event(void)
1313 apm_event_t event
= APM_NO_EVENTS
; /* silence gcc */
1314 apm_eventinfo_t info
;
1316 static int notified
;
1318 /* we don't use the eventinfo */
1319 error
= apm_get_event(&event
, &info
);
1320 if (error
== APM_SUCCESS
)
1323 if ((error
!= APM_NO_EVENTS
) && (notified
++ == 0))
1324 apm_error("get_event", error
);
1329 static void check_events(void)
1332 static unsigned long last_resume
;
1333 static int ignore_bounce
;
1335 while ((event
= get_event()) != 0) {
1337 if (event
<= NR_APM_EVENT_NAME
)
1338 printk(KERN_DEBUG
"apm: received %s notify\n",
1339 apm_event_name
[event
- 1]);
1341 printk(KERN_DEBUG
"apm: received unknown "
1342 "event 0x%02x\n", event
);
1345 && (time_after(jiffies
, last_resume
+ bounce_interval
)))
1349 case APM_SYS_STANDBY
:
1350 case APM_USER_STANDBY
:
1351 queue_event(event
, NULL
);
1352 if (standbys_pending
<= 0)
1356 case APM_USER_SUSPEND
:
1357 #ifdef CONFIG_APM_IGNORE_USER_SUSPEND
1358 if (apm_info
.connection_version
> 0x100)
1359 set_system_power_state(APM_STATE_REJECT
);
1362 case APM_SYS_SUSPEND
:
1363 if (ignore_bounce
) {
1364 if (apm_info
.connection_version
> 0x100)
1365 set_system_power_state(APM_STATE_REJECT
);
1369 * If we are already processing a SUSPEND,
1370 * then further SUSPEND events from the BIOS
1371 * will be ignored. We also return here to
1372 * cope with the fact that the Thinkpads keep
1373 * sending a SUSPEND event until something else
1376 if (ignore_sys_suspend
)
1378 ignore_sys_suspend
= 1;
1379 queue_event(event
, NULL
);
1380 if (suspends_pending
<= 0)
1384 case APM_NORMAL_RESUME
:
1385 case APM_CRITICAL_RESUME
:
1386 case APM_STANDBY_RESUME
:
1387 ignore_sys_suspend
= 0;
1388 last_resume
= jiffies
;
1390 if ((event
!= APM_NORMAL_RESUME
)
1391 || (ignore_normal_resume
== 0)) {
1392 dpm_resume_end(PMSG_RESUME
);
1393 queue_event(event
, NULL
);
1395 ignore_normal_resume
= 0;
1398 case APM_CAPABILITY_CHANGE
:
1399 case APM_LOW_BATTERY
:
1400 case APM_POWER_STATUS_CHANGE
:
1401 queue_event(event
, NULL
);
1402 /* If needed, notify drivers here */
1405 case APM_UPDATE_TIME
:
1408 case APM_CRITICAL_SUSPEND
:
1410 * We are not allowed to reject a critical suspend.
1418 static void apm_event_handler(void)
1420 static int pending_count
= 4;
1423 if ((standbys_pending
> 0) || (suspends_pending
> 0)) {
1424 if ((apm_info
.connection_version
> 0x100) &&
1425 (pending_count
-- <= 0)) {
1428 printk(KERN_DEBUG
"apm: setting state busy\n");
1429 err
= set_system_power_state(APM_STATE_BUSY
);
1431 apm_error("busy", err
);
1439 * This is the APM thread main loop.
1442 static void apm_mainloop(void)
1444 DECLARE_WAITQUEUE(wait
, current
);
1446 add_wait_queue(&apm_waitqueue
, &wait
);
1447 set_current_state(TASK_INTERRUPTIBLE
);
1449 schedule_timeout(APM_CHECK_TIMEOUT
);
1450 if (kthread_should_stop())
1453 * Ok, check all events, check for idle (and mark us sleeping
1454 * so as not to count towards the load average)..
1456 set_current_state(TASK_INTERRUPTIBLE
);
1457 apm_event_handler();
1459 remove_wait_queue(&apm_waitqueue
, &wait
);
1462 static int check_apm_user(struct apm_user
*as
, const char *func
)
1464 if (as
== NULL
|| as
->magic
!= APM_BIOS_MAGIC
) {
1465 pr_err("%s passed bad filp\n", func
);
1471 static ssize_t
do_read(struct file
*fp
, char __user
*buf
, size_t count
, loff_t
*ppos
)
1473 struct apm_user
*as
;
1477 as
= fp
->private_data
;
1478 if (check_apm_user(as
, "read"))
1480 if ((int)count
< sizeof(apm_event_t
))
1482 if ((queue_empty(as
)) && (fp
->f_flags
& O_NONBLOCK
))
1484 wait_event_interruptible(apm_waitqueue
, !queue_empty(as
));
1486 while ((i
>= sizeof(event
)) && !queue_empty(as
)) {
1487 event
= get_queued_event(as
);
1488 if (copy_to_user(buf
, &event
, sizeof(event
))) {
1494 case APM_SYS_SUSPEND
:
1495 case APM_USER_SUSPEND
:
1496 as
->suspends_read
++;
1499 case APM_SYS_STANDBY
:
1500 case APM_USER_STANDBY
:
1501 as
->standbys_read
++;
1504 buf
+= sizeof(event
);
1509 if (signal_pending(current
))
1510 return -ERESTARTSYS
;
1514 static __poll_t
do_poll(struct file
*fp
, poll_table
*wait
)
1516 struct apm_user
*as
;
1518 as
= fp
->private_data
;
1519 if (check_apm_user(as
, "poll"))
1521 poll_wait(fp
, &apm_waitqueue
, wait
);
1522 if (!queue_empty(as
))
1523 return EPOLLIN
| EPOLLRDNORM
;
1527 static long do_ioctl(struct file
*filp
, u_int cmd
, u_long arg
)
1529 struct apm_user
*as
;
1532 as
= filp
->private_data
;
1533 if (check_apm_user(as
, "ioctl"))
1535 if (!as
->suser
|| !as
->writer
)
1538 case APM_IOC_STANDBY
:
1539 mutex_lock(&apm_mutex
);
1540 if (as
->standbys_read
> 0) {
1541 as
->standbys_read
--;
1542 as
->standbys_pending
--;
1545 queue_event(APM_USER_STANDBY
, as
);
1546 if (standbys_pending
<= 0)
1548 mutex_unlock(&apm_mutex
);
1550 case APM_IOC_SUSPEND
:
1551 mutex_lock(&apm_mutex
);
1552 if (as
->suspends_read
> 0) {
1553 as
->suspends_read
--;
1554 as
->suspends_pending
--;
1557 queue_event(APM_USER_SUSPEND
, as
);
1558 if (suspends_pending
<= 0) {
1560 mutex_unlock(&apm_mutex
);
1562 as
->suspend_wait
= 1;
1563 mutex_unlock(&apm_mutex
);
1564 wait_event_interruptible(apm_suspend_waitqueue
,
1565 as
->suspend_wait
== 0);
1566 ret
= as
->suspend_result
;
1575 static int do_release(struct inode
*inode
, struct file
*filp
)
1577 struct apm_user
*as
;
1579 as
= filp
->private_data
;
1580 if (check_apm_user(as
, "release"))
1582 filp
->private_data
= NULL
;
1583 if (as
->standbys_pending
> 0) {
1584 standbys_pending
-= as
->standbys_pending
;
1585 if (standbys_pending
<= 0)
1588 if (as
->suspends_pending
> 0) {
1589 suspends_pending
-= as
->suspends_pending
;
1590 if (suspends_pending
<= 0)
1593 spin_lock(&user_list_lock
);
1594 if (user_list
== as
)
1595 user_list
= as
->next
;
1597 struct apm_user
*as1
;
1599 for (as1
= user_list
;
1600 (as1
!= NULL
) && (as1
->next
!= as
);
1604 pr_err("filp not in user list\n");
1606 as1
->next
= as
->next
;
1608 spin_unlock(&user_list_lock
);
1613 static int do_open(struct inode
*inode
, struct file
*filp
)
1615 struct apm_user
*as
;
1617 as
= kmalloc(sizeof(*as
), GFP_KERNEL
);
1621 as
->magic
= APM_BIOS_MAGIC
;
1622 as
->event_tail
= as
->event_head
= 0;
1623 as
->suspends_pending
= as
->standbys_pending
= 0;
1624 as
->suspends_read
= as
->standbys_read
= 0;
1626 * XXX - this is a tiny bit broken, when we consider BSD
1627 * process accounting. If the device is opened by root, we
1628 * instantly flag that we used superuser privs. Who knows,
1629 * we might close the device immediately without doing a
1630 * privileged operation -- cevans
1632 as
->suser
= capable(CAP_SYS_ADMIN
);
1633 as
->writer
= (filp
->f_mode
& FMODE_WRITE
) == FMODE_WRITE
;
1634 as
->reader
= (filp
->f_mode
& FMODE_READ
) == FMODE_READ
;
1635 spin_lock(&user_list_lock
);
1636 as
->next
= user_list
;
1638 spin_unlock(&user_list_lock
);
1639 filp
->private_data
= as
;
1643 #ifdef CONFIG_PROC_FS
1644 static int proc_apm_show(struct seq_file
*m
, void *v
)
1650 unsigned short ac_line_status
= 0xff;
1651 unsigned short battery_status
= 0xff;
1652 unsigned short battery_flag
= 0xff;
1653 int percentage
= -1;
1654 int time_units
= -1;
1657 if ((num_online_cpus() == 1) &&
1658 !(error
= apm_get_power_status(&bx
, &cx
, &dx
))) {
1659 ac_line_status
= (bx
>> 8) & 0xff;
1660 battery_status
= bx
& 0xff;
1661 if ((cx
& 0xff) != 0xff)
1662 percentage
= cx
& 0xff;
1664 if (apm_info
.connection_version
> 0x100) {
1665 battery_flag
= (cx
>> 8) & 0xff;
1667 units
= (dx
& 0x8000) ? "min" : "sec";
1668 time_units
= dx
& 0x7fff;
1672 /* Arguments, with symbols from linux/apm_bios.h. Information is
1673 from the Get Power Status (0x0a) call unless otherwise noted.
1675 0) Linux driver version (this will change if format changes)
1676 1) APM BIOS Version. Usually 1.0, 1.1 or 1.2.
1677 2) APM flags from APM Installation Check (0x00):
1678 bit 0: APM_16_BIT_SUPPORT
1679 bit 1: APM_32_BIT_SUPPORT
1680 bit 2: APM_IDLE_SLOWS_CLOCK
1681 bit 3: APM_BIOS_DISABLED
1682 bit 4: APM_BIOS_DISENGAGED
1686 0x02: On backup power (BIOS >= 1.1 only)
1693 0x04: Selected battery not present (BIOS >= 1.2 only)
1700 bit 7: No system battery
1702 6) Remaining battery life (percentage of charge):
1705 7) Remaining battery life (time units):
1706 Number of remaining minutes or seconds
1708 8) min = minutes; sec = seconds */
1710 seq_printf(m
, "%s %d.%d 0x%02x 0x%02x 0x%02x 0x%02x %d%% %d %s\n",
1712 (apm_info
.bios
.version
>> 8) & 0xff,
1713 apm_info
.bios
.version
& 0xff,
1714 apm_info
.bios
.flags
,
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 const struct dmi_system_id apm_dmi_table
[] __initconst
= {
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 || 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 pr_notice("disabled on user request.\n");
2321 if ((num_online_cpus() > 1) && !power_off
&& !smp
) {
2322 pr_notice("disabled - APM is not SMP safe.\n");
2323 apm_info
.disabled
= 1;
2326 if (!acpi_disabled
) {
2327 pr_notice("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_rw(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_single("apm", 0, NULL
, proc_apm_show
);
2359 kapmd_task
= kthread_create(apm
, NULL
, "kapmd");
2360 if (IS_ERR(kapmd_task
)) {
2361 pr_err("disabled - Unable to start kernel thread\n");
2362 err
= PTR_ERR(kapmd_task
);
2364 remove_proc_entry("apm", NULL
);
2367 wake_up_process(kapmd_task
);
2369 if (num_online_cpus() > 1 && !smp
) {
2371 "apm: disabled - APM is not SMP safe (power off active).\n");
2376 * Note we don't actually care if the misc_device cannot be registered.
2377 * this driver can do its job without it, even if userspace can't
2378 * control it. just log the error
2380 if (misc_register(&apm_device
))
2381 printk(KERN_WARNING
"apm: Could not register misc device.\n");
2384 idle_period
= (idle_period
* HZ
) / 100;
2385 if (idle_threshold
< 100) {
2386 cpuidle_poll_state_init(&apm_idle_driver
);
2387 if (!cpuidle_register_driver(&apm_idle_driver
))
2388 if (cpuidle_register_device(&apm_cpuidle_device
))
2389 cpuidle_unregister_driver(&apm_idle_driver
);
2395 static void __exit
apm_exit(void)
2399 cpuidle_unregister_device(&apm_cpuidle_device
);
2400 cpuidle_unregister_driver(&apm_idle_driver
);
2402 if (((apm_info
.bios
.flags
& APM_BIOS_DISENGAGED
) == 0)
2403 && (apm_info
.connection_version
> 0x0100)) {
2404 error
= apm_engage_power_management(APM_DEVICE_ALL
, 0);
2406 apm_error("disengage power management", error
);
2408 misc_deregister(&apm_device
);
2409 remove_proc_entry("apm", NULL
);
2411 pm_power_off
= NULL
;
2413 kthread_stop(kapmd_task
);
2418 module_init(apm_init
);
2419 module_exit(apm_exit
);
2421 MODULE_AUTHOR("Stephen Rothwell");
2422 MODULE_DESCRIPTION("Advanced Power Management");
2423 MODULE_LICENSE("GPL");
2424 module_param(debug
, bool, 0644);
2425 MODULE_PARM_DESC(debug
, "Enable debug mode");
2426 module_param(power_off
, bool, 0444);
2427 MODULE_PARM_DESC(power_off
, "Enable power off");
2428 module_param(bounce_interval
, int, 0444);
2429 MODULE_PARM_DESC(bounce_interval
,
2430 "Set the number of ticks to ignore suspend bounces");
2431 module_param(allow_ints
, bool, 0444);
2432 MODULE_PARM_DESC(allow_ints
, "Allow interrupts during BIOS calls");
2433 module_param(broken_psr
, bool, 0444);
2434 MODULE_PARM_DESC(broken_psr
, "BIOS has a broken GetPowerStatus call");
2435 module_param(realmode_power_off
, bool, 0444);
2436 MODULE_PARM_DESC(realmode_power_off
,
2437 "Switch to real mode before powering off");
2438 module_param(idle_threshold
, int, 0444);
2439 MODULE_PARM_DESC(idle_threshold
,
2440 "System idle percentage above which to make APM BIOS idle calls");
2441 module_param(idle_period
, int, 0444);
2442 MODULE_PARM_DESC(idle_period
,
2443 "Period (in sec/100) over which to calculate the idle percentage");
2444 module_param(smp
, bool, 0444);
2445 MODULE_PARM_DESC(smp
,
2446 "Set this to enable APM use on an SMP platform. Use with caution on older systems");
2447 MODULE_ALIAS_MISCDEV(APM_MINOR_DEV
);