2 * APM BIOS driver for Linux
3 * Copyright 1994-2001 Stephen Rothwell (sfr@canb.auug.org.au)
5 * Initial development of this driver was funded by NEC Australia P/L
8 * This program is free software; you can redistribute it and/or modify it
9 * under the terms of the GNU General Public License as published by the
10 * Free Software Foundation; either version 2, or (at your option) any
13 * This program is distributed in the hope that it will be useful, but
14 * WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * General Public License for more details.
18 * October 1995, Rik Faith (faith@cs.unc.edu):
19 * Minor enhancements and updates (to the patch set) for 1.3.x
21 * January 1996, Rik Faith (faith@cs.unc.edu):
22 * Make /proc/apm easy to format (bump driver version)
23 * March 1996, Rik Faith (faith@cs.unc.edu):
24 * Prohibit APM BIOS calls unless apm_enabled.
25 * (Thanks to Ulrich Windl <Ulrich.Windl@rz.uni-regensburg.de>)
26 * April 1996, Stephen Rothwell (sfr@canb.auug.org.au)
28 * May 1996, Version 1.2
29 * Feb 1998, Version 1.3
30 * Feb 1998, Version 1.4
31 * Aug 1998, Version 1.5
32 * Sep 1998, Version 1.6
33 * Nov 1998, Version 1.7
34 * Jan 1999, Version 1.8
35 * Jan 1999, Version 1.9
36 * Oct 1999, Version 1.10
37 * Nov 1999, Version 1.11
38 * Jan 2000, Version 1.12
39 * Feb 2000, Version 1.13
40 * Nov 2000, Version 1.14
41 * Oct 2001, Version 1.15
42 * Jan 2002, Version 1.16
43 * Oct 2002, Version 1.16ac
46 * 0.6b: first version in official kernel, Linux 1.3.46
47 * 0.7: changed /proc/apm format, Linux 1.3.58
48 * 0.8: fixed gcc 2.7.[12] compilation problems, Linux 1.3.59
49 * 0.9: only call bios if bios is present, Linux 1.3.72
50 * 1.0: use fixed device number, consolidate /proc/apm into this file,
52 * 1.1: support user-space standby and suspend, power off after system
53 * halted, Linux 1.3.98
54 * 1.2: When resetting RTC after resume, take care so that the time
55 * is only incorrect by 30-60mS (vs. 1S previously) (Gabor J. Toth
56 * <jtoth@princeton.edu>); improve interaction between
57 * screen-blanking and gpm (Stephen Rothwell); Linux 1.99.4
58 * 1.2a:Simple change to stop mysterious bug reports with SMP also added
59 * levels to the printk calls. APM is not defined for SMP machines.
60 * The new replacement for it is, but Linux doesn't yet support this.
61 * Alan Cox Linux 2.1.55
62 * 1.3: Set up a valid data descriptor 0x40 for buggy BIOS's
63 * 1.4: Upgraded to support APM 1.2. Integrated ThinkPad suspend patch by
64 * Dean Gaudet <dgaudet@arctic.org>.
65 * C. Scott Ananian <cananian@alumni.princeton.edu> Linux 2.1.87
66 * 1.5: Fix segment register reloading (in case of bad segments saved
69 * 1.6: Cope with complier/assembler differences.
70 * Only try to turn off the first display device.
71 * Fix OOPS at power off with no APM BIOS by Jan Echternach
72 * <echter@informatik.uni-rostock.de>
74 * 1.7: Modify driver's cached copy of the disabled/disengaged flags
75 * to reflect current state of APM BIOS.
76 * Chris Rankin <rankinc@bellsouth.net>
77 * Reset interrupt 0 timer to 100Hz after suspend
78 * Chad Miller <cmiller@surfsouth.com>
79 * Add CONFIG_APM_IGNORE_SUSPEND_BOUNCE
80 * Richard Gooch <rgooch@atnf.csiro.au>
81 * Allow boot time disabling of APM
82 * Make boot messages far less verbose by default
85 * 1.8: Add CONFIG_APM_RTC_IS_GMT
86 * Richard Gooch <rgooch@atnf.csiro.au>
87 * change APM_NOINTS to CONFIG_APM_ALLOW_INTS
88 * remove dependency on CONFIG_PROC_FS
90 * 1.9: Fix small typo. <laslo@wodip.opole.pl>
91 * Try to cope with BIOS's that need to have all display
92 * devices blanked and not just the first one.
93 * Ross Paterson <ross@soi.city.ac.uk>
94 * Fix segment limit setting it has always been wrong as
95 * the segments needed to have byte granularity.
96 * Mark a few things __init.
97 * Add hack to allow power off of SMP systems by popular request.
98 * Use CONFIG_SMP instead of __SMP__
99 * Ignore BOUNCES for three seconds.
101 * 1.10: Fix for Thinkpad return code.
102 * Merge 2.2 and 2.3 drivers.
103 * Remove APM dependencies in arch/i386/kernel/process.c
104 * Remove APM dependencies in drivers/char/sysrq.c
105 * Reset time across standby.
106 * Allow more inititialisation on SMP.
107 * Remove CONFIG_APM_POWER_OFF and make it boot time
108 * configurable (default on).
109 * Make debug only a boot time parameter (remove APM_DEBUG).
110 * Try to blank all devices on any error.
111 * 1.11: Remove APM dependencies in drivers/char/console.c
112 * Check nr_running to detect if we are idle (from
113 * Borislav Deianov <borislav@lix.polytechnique.fr>)
114 * Fix for bioses that don't zero the top part of the
115 * entrypoint offset (Mario Sitta <sitta@al.unipmn.it>)
116 * (reported by Panos Katsaloulis <teras@writeme.com>).
117 * Real mode power off patch (Walter Hofmann
118 * <Walter.Hofmann@physik.stud.uni-erlangen.de>).
119 * 1.12: Remove CONFIG_SMP as the compiler will optimize
120 * the code away anyway (smp_num_cpus == 1 in UP)
121 * noted by Artur Skawina <skawina@geocities.com>.
122 * Make power off under SMP work again.
123 * Fix thinko with initial engaging of BIOS.
124 * Make sure power off only happens on CPU 0
125 * (Paul "Rusty" Russell <rusty@rustcorp.com.au>).
126 * Do error notification to user mode if BIOS calls fail.
127 * Move entrypoint offset fix to ...boot/setup.S
128 * where it belongs (Cosmos <gis88564@cis.nctu.edu.tw>).
129 * Remove smp-power-off. SMP users must now specify
130 * "apm=power-off" on the kernel command line. Suggested
131 * by Jim Avera <jima@hal.com>, modified by Alan Cox
132 * <alan@lxorguk.ukuu.org.uk>.
133 * Register the /proc/apm entry even on SMP so that
134 * scripts that check for it before doing power off
135 * work (Jim Avera <jima@hal.com>).
136 * 1.13: Changes for new pm_ interfaces (Andy Henroid
137 * <andy_henroid@yahoo.com>).
138 * Modularize the code.
139 * Fix the Thinkpad (again) :-( (CONFIG_APM_IGNORE_MULTIPLE_SUSPENDS
140 * is now the way life works).
141 * Fix thinko in suspend() (wrong return).
142 * Notify drivers on critical suspend.
143 * Make kapmd absorb more idle time (Pavel Machek <pavel@suse.cz>
145 * Disable interrupts while we are suspended (Andy Henroid
146 * <andy_henroid@yahoo.com> fixed by sfr).
147 * Make power off work on SMP again (Tony Hoyle
148 * <tmh@magenta-logic.com> and <zlatko@iskon.hr>) modified by sfr.
149 * Remove CONFIG_APM_SUSPEND_BOUNCE. The bounce ignore
150 * interval is now configurable.
151 * 1.14: Make connection version persist across module unload/load.
152 * Enable and engage power management earlier.
153 * Disengage power management on module unload.
154 * Changed to use the sysrq-register hack for registering the
155 * power off function called by magic sysrq based upon discussions
156 * in irc://irc.openprojects.net/#kernelnewbies
157 * (Crutcher Dunnavant <crutcher+kernel@datastacks.com>).
158 * Make CONFIG_APM_REAL_MODE_POWER_OFF run time configurable.
159 * (Arjan van de Ven <arjanv@redhat.com>) modified by sfr.
160 * Work around byte swap bug in one of the Vaio's BIOS's
161 * (Marc Boucher <marc@mbsi.ca>).
162 * Exposed the disable flag to dmi so that we can handle known
163 * broken APM (Alan Cox <alan@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 via anonymous ftp from
193 * ftp://ftp.intel.com/pub/IAL/software_specs/apmv11.doc. It is also
194 * available from Microsoft by calling 206.882.8080.]
197 * Intel Corporation, Microsoft Corporation. Advanced Power Management
198 * (APM) BIOS Interface Specification, Revision 1.2, February 1996.
200 * [This document is available from Microsoft at:
201 * http://www.microsoft.com/whdc/archive/amp_12.mspx]
204 #include <linux/module.h>
206 #include <linux/poll.h>
207 #include <linux/smp_lock.h>
208 #include <linux/types.h>
209 #include <linux/stddef.h>
210 #include <linux/timer.h>
211 #include <linux/fcntl.h>
212 #include <linux/slab.h>
213 #include <linux/stat.h>
214 #include <linux/proc_fs.h>
215 #include <linux/seq_file.h>
216 #include <linux/miscdevice.h>
217 #include <linux/apm_bios.h>
218 #include <linux/init.h>
219 #include <linux/time.h>
220 #include <linux/sched.h>
221 #include <linux/pm.h>
222 #include <linux/capability.h>
223 #include <linux/device.h>
224 #include <linux/kernel.h>
225 #include <linux/freezer.h>
226 #include <linux/smp.h>
227 #include <linux/dmi.h>
228 #include <linux/suspend.h>
229 #include <linux/kthread.h>
230 #include <linux/jiffies.h>
232 #include <asm/system.h>
233 #include <asm/uaccess.h>
234 #include <asm/desc.h>
235 #include <asm/i8253.h>
236 #include <asm/olpc.h>
237 #include <asm/paravirt.h>
238 #include <asm/reboot.h>
240 #if defined(CONFIG_APM_DISPLAY_BLANK) && defined(CONFIG_VT)
241 extern int (*console_blank_hook
)(int);
245 * The apm_bios device is one of the misc char devices.
246 * This is its minor number.
248 #define APM_MINOR_DEV 134
251 * See Documentation/Config.help for the configuration options.
253 * Various options can be changed at boot time as follows:
254 * (We allow underscores for compatibility with the modules code)
255 * apm=on/off enable/disable APM
256 * [no-]allow[-_]ints allow interrupts during BIOS calls
257 * [no-]broken[-_]psr BIOS has a broken GetPowerStatus call
258 * [no-]realmode[-_]power[-_]off switch to real mode before
260 * [no-]debug log some debugging messages
261 * [no-]power[-_]off power off on shutdown
262 * [no-]smp Use apm even on an SMP box
263 * bounce[-_]interval=<n> number of ticks to ignore suspend
265 * idle[-_]threshold=<n> System idle percentage above which to
266 * make APM BIOS idle calls. Set it to
268 * idle[-_]period=<n> Period (in 1/100s of a second) over
269 * which the idle percentage is
273 /* KNOWN PROBLEM MACHINES:
275 * U: TI 4000M TravelMate: BIOS is *NOT* APM compliant
276 * [Confirmed by TI representative]
277 * ?: ACER 486DX4/75: uses dseg 0040, in violation of APM specification
278 * [Confirmed by BIOS disassembly]
279 * [This may work now ...]
280 * P: Toshiba 1950S: battery life information only gets updated after resume
281 * P: Midwest Micro Soundbook Elite DX2/66 monochrome: screen blanking
282 * broken in BIOS [Reported by Garst R. Reese <reese@isn.net>]
283 * ?: AcerNote-950: oops on reading /proc/apm - workaround is a WIP
284 * Neale Banks <neale@lowendale.com.au> December 2000
286 * Legend: U = unusable with APM patches
287 * P = partially usable with APM patches
291 * Define as 1 to make the driver always call the APM BIOS busy
292 * routine even if the clock was not reported as slowed by the
293 * idle routine. Otherwise, define as 0.
295 #define ALWAYS_CALL_BUSY 1
298 * Define to make the APM BIOS calls zero all data segment registers (so
299 * that an incorrect BIOS implementation will cause a kernel panic if it
300 * tries to write to arbitrary memory).
302 #define APM_ZERO_SEGS
307 * Define to re-initialize the interrupt 0 timer to 100 Hz after a suspend.
308 * This patched by Chad Miller <cmiller@surfsouth.com>, original code by
309 * David Chen <chen@ctpa04.mit.edu>
311 #undef INIT_TIMER_AFTER_SUSPEND
313 #ifdef INIT_TIMER_AFTER_SUSPEND
314 #include <linux/timex.h>
316 #include <linux/delay.h>
320 * Need to poll the APM BIOS every second
322 #define APM_CHECK_TIMEOUT (HZ)
325 * Ignore suspend events for this amount of time after a resume
327 #define DEFAULT_BOUNCE_INTERVAL (3 * HZ)
330 * Maximum number of events stored
332 #define APM_MAX_EVENTS 20
335 * The per-file APM data
339 struct apm_user
*next
;
340 unsigned int suser
: 1;
341 unsigned int writer
: 1;
342 unsigned int reader
: 1;
343 unsigned int suspend_wait
: 1;
345 int suspends_pending
;
346 int standbys_pending
;
351 apm_event_t events
[APM_MAX_EVENTS
];
355 * The magic number in apm_user
357 #define APM_BIOS_MAGIC 0x4101
360 * idle percentage above which bios idle calls are done
362 #ifdef CONFIG_APM_CPU_IDLE
363 #define DEFAULT_IDLE_THRESHOLD 95
365 #define DEFAULT_IDLE_THRESHOLD 100
367 #define DEFAULT_IDLE_PERIOD (100 / 3)
373 unsigned long offset
;
374 unsigned short segment
;
376 static int clock_slowed
;
377 static int idle_threshold __read_mostly
= DEFAULT_IDLE_THRESHOLD
;
378 static int idle_period __read_mostly
= DEFAULT_IDLE_PERIOD
;
379 static int set_pm_idle
;
380 static int suspends_pending
;
381 static int standbys_pending
;
382 static int ignore_sys_suspend
;
383 static int ignore_normal_resume
;
384 static int bounce_interval __read_mostly
= DEFAULT_BOUNCE_INTERVAL
;
386 static int debug __read_mostly
;
387 static int smp __read_mostly
;
388 static int apm_disabled
= -1;
390 static int power_off
;
392 static int power_off
= 1;
394 static int realmode_power_off
;
395 #ifdef CONFIG_APM_ALLOW_INTS
396 static int allow_ints
= 1;
398 static int allow_ints
;
400 static int broken_psr
;
402 static DECLARE_WAIT_QUEUE_HEAD(apm_waitqueue
);
403 static DECLARE_WAIT_QUEUE_HEAD(apm_suspend_waitqueue
);
404 static struct apm_user
*user_list
;
405 static DEFINE_SPINLOCK(user_list_lock
);
408 * Set up a segment that references the real mode segment 0x40
409 * that extends up to the end of page zero (that we have reserved).
410 * This is for buggy BIOS's that refer to (real mode) segment 0x40
411 * even though they are called in protected mode.
413 static struct desc_struct bad_bios_desc
= GDT_ENTRY_INIT(0x4092,
414 (unsigned long)__va(0x400UL
), PAGE_SIZE
- 0x400 - 1);
416 static const char driver_version
[] = "1.16ac"; /* no spaces */
418 static struct task_struct
*kapmd_task
;
421 * APM event names taken from the APM 1.2 specification. These are
422 * the message codes that the BIOS uses to tell us about events
424 static const char * const apm_event_name
[] = {
430 "power status change",
435 "system standby resume",
436 "capabilities change"
438 #define NR_APM_EVENT_NAME ARRAY_SIZE(apm_event_name)
440 typedef struct lookup_t
{
446 * The BIOS returns a set of standard error codes in AX when the
450 static const lookup_t error_table
[] = {
451 /* N/A { APM_SUCCESS, "Operation succeeded" }, */
452 { APM_DISABLED
, "Power management disabled" },
453 { APM_CONNECTED
, "Real mode interface already connected" },
454 { APM_NOT_CONNECTED
, "Interface not connected" },
455 { APM_16_CONNECTED
, "16 bit interface already connected" },
456 /* N/A { APM_16_UNSUPPORTED, "16 bit interface not supported" }, */
457 { APM_32_CONNECTED
, "32 bit interface already connected" },
458 { APM_32_UNSUPPORTED
, "32 bit interface not supported" },
459 { APM_BAD_DEVICE
, "Unrecognized device ID" },
460 { APM_BAD_PARAM
, "Parameter out of range" },
461 { APM_NOT_ENGAGED
, "Interface not engaged" },
462 { APM_BAD_FUNCTION
, "Function not supported" },
463 { APM_RESUME_DISABLED
, "Resume timer disabled" },
464 { APM_BAD_STATE
, "Unable to enter requested state" },
465 /* N/A { APM_NO_EVENTS, "No events pending" }, */
466 { APM_NO_ERROR
, "BIOS did not set a return code" },
467 { APM_NOT_PRESENT
, "No APM present" }
469 #define ERROR_COUNT ARRAY_SIZE(error_table)
472 * apm_error - display an APM error
473 * @str: information string
474 * @err: APM BIOS return code
476 * Write a meaningful log entry to the kernel log in the event of
477 * an APM error. Note that this also handles (negative) kernel errors.
480 static void apm_error(char *str
, int err
)
484 for (i
= 0; i
< ERROR_COUNT
; i
++)
485 if (error_table
[i
].key
== err
)
488 printk(KERN_NOTICE
"apm: %s: %s\n", str
, error_table
[i
].msg
);
490 printk(KERN_NOTICE
"apm: %s: linux error code %i\n", str
, err
);
492 printk(KERN_NOTICE
"apm: %s: unknown error code %#2.2x\n",
497 * These are the actual BIOS calls. Depending on APM_ZERO_SEGS and
498 * apm_info.allow_ints, we are being really paranoid here! Not only
499 * are interrupts disabled, but all the segment registers (except SS)
500 * are saved and zeroed this means that if the BIOS tries to reference
501 * any data without explicitly loading the segment registers, the kernel
502 * will fault immediately rather than have some unforeseen circumstances
503 * for the rest of the kernel. And it will be very obvious! :-) Doing
504 * this depends on CS referring to the same physical memory as DS so that
505 * DS can be zeroed before the call. Unfortunately, we can't do anything
506 * about the stack segment/pointer. Also, we tell the compiler that
507 * everything could change.
509 * Also, we KNOW that for the non error case of apm_bios_call, there
510 * is no useful data returned in the low order 8 bits of eax.
513 static inline unsigned long __apm_irq_save(void)
516 local_save_flags(flags
);
517 if (apm_info
.allow_ints
) {
518 if (irqs_disabled_flags(flags
))
526 #define apm_irq_save(flags) \
527 do { flags = __apm_irq_save(); } while (0)
529 static inline void apm_irq_restore(unsigned long flags
)
531 if (irqs_disabled_flags(flags
))
533 else if (irqs_disabled())
538 # define APM_DECL_SEGS \
539 unsigned int saved_fs; unsigned int saved_gs;
540 # define APM_DO_SAVE_SEGS \
541 savesegment(fs, saved_fs); savesegment(gs, saved_gs)
542 # define APM_DO_RESTORE_SEGS \
543 loadsegment(fs, saved_fs); loadsegment(gs, saved_gs)
545 # define APM_DECL_SEGS
546 # define APM_DO_SAVE_SEGS
547 # define APM_DO_RESTORE_SEGS
550 struct apm_bios_call
{
560 /* Error: -ENOMEM, or bits 8-15 of eax */
565 * __apm_bios_call - Make an APM BIOS 32bit call
566 * @_call: pointer to struct apm_bios_call.
568 * Make an APM call using the 32bit protected mode interface. The
569 * caller is responsible for knowing if APM BIOS is configured and
570 * enabled. This call can disable interrupts for a long period of
571 * time on some laptops. The return value is in AH and the carry
572 * flag is loaded into AL. If there is an error, then the error
573 * code is returned in AH (bits 8-15 of eax) and this function
576 * Note: this makes the call on the current CPU.
578 static long __apm_bios_call(void *_call
)
583 struct desc_struct save_desc_40
;
584 struct desc_struct
*gdt
;
585 struct apm_bios_call
*call
= _call
;
589 gdt
= get_cpu_gdt_table(cpu
);
590 save_desc_40
= gdt
[0x40 / 8];
591 gdt
[0x40 / 8] = bad_bios_desc
;
595 apm_bios_call_asm(call
->func
, call
->ebx
, call
->ecx
,
596 &call
->eax
, &call
->ebx
, &call
->ecx
, &call
->edx
,
599 apm_irq_restore(flags
);
600 gdt
[0x40 / 8] = save_desc_40
;
603 return call
->eax
& 0xff;
606 /* Run __apm_bios_call or __apm_bios_call_simple on CPU 0 */
607 static int on_cpu0(long (*fn
)(void *), struct apm_bios_call
*call
)
611 /* Don't bother with work_on_cpu in the common case, so we don't
612 * have to worry about OOM or overhead. */
613 if (get_cpu() == 0) {
618 ret
= work_on_cpu(0, fn
, call
);
621 /* work_on_cpu can fail with -ENOMEM */
625 call
->err
= (call
->eax
>> 8) & 0xff;
631 * apm_bios_call - Make an APM BIOS 32bit call (on CPU 0)
632 * @call: the apm_bios_call registers.
634 * If there is an error, it is returned in @call.err.
636 static int apm_bios_call(struct apm_bios_call
*call
)
638 return on_cpu0(__apm_bios_call
, call
);
642 * __apm_bios_call_simple - Make an APM BIOS 32bit call (on CPU 0)
643 * @_call: pointer to struct apm_bios_call.
645 * Make a BIOS call that returns one value only, or just status.
646 * If there is an error, then the error code is returned in AH
647 * (bits 8-15 of eax) and this function returns non-zero (it can
648 * also return -ENOMEM). This is used for simpler BIOS operations.
649 * This call may hold interrupts off for a long time on some laptops.
651 * Note: this makes the call on the current CPU.
653 static long __apm_bios_call_simple(void *_call
)
659 struct desc_struct save_desc_40
;
660 struct desc_struct
*gdt
;
661 struct apm_bios_call
*call
= _call
;
665 gdt
= get_cpu_gdt_table(cpu
);
666 save_desc_40
= gdt
[0x40 / 8];
667 gdt
[0x40 / 8] = bad_bios_desc
;
671 error
= apm_bios_call_simple_asm(call
->func
, call
->ebx
, call
->ecx
,
674 apm_irq_restore(flags
);
675 gdt
[0x40 / 8] = save_desc_40
;
681 * apm_bios_call_simple - make a simple APM BIOS 32bit call
682 * @func: APM function to invoke
683 * @ebx_in: EBX register value for BIOS call
684 * @ecx_in: ECX register value for BIOS call
685 * @eax: EAX register on return from the BIOS call
688 * Make a BIOS call that returns one value only, or just status.
689 * If there is an error, then the error code is returned in @err
690 * and this function returns non-zero. This is used for simpler
691 * BIOS operations. This call may hold interrupts off for a long
692 * time on some laptops.
694 static int apm_bios_call_simple(u32 func
, u32 ebx_in
, u32 ecx_in
, u32
*eax
,
697 struct apm_bios_call call
;
704 ret
= on_cpu0(__apm_bios_call_simple
, &call
);
711 * apm_driver_version - APM driver version
712 * @val: loaded with the APM version on return
714 * Retrieve the APM version supported by the BIOS. This is only
715 * supported for APM 1.1 or higher. An error indicates APM 1.0 is
718 * On entry val should point to a value indicating the APM driver
719 * version with the high byte being the major and the low byte the
720 * minor number both in BCD
722 * On return it will hold the BIOS revision supported in the
726 static int apm_driver_version(u_short
*val
)
731 if (apm_bios_call_simple(APM_FUNC_VERSION
, 0, *val
, &eax
, &err
))
738 * apm_get_event - get an APM event from the BIOS
739 * @event: pointer to the event
740 * @info: point to the event information
742 * The APM BIOS provides a polled information for event
743 * reporting. The BIOS expects to be polled at least every second
744 * when events are pending. When a message is found the caller should
745 * poll until no more messages are present. However, this causes
746 * problems on some laptops where a suspend event notification is
747 * not cleared until it is acknowledged.
749 * Additional information is returned in the info pointer, providing
750 * that APM 1.2 is in use. If no messges are pending the value 0x80
751 * is returned (No power management events pending).
753 static int apm_get_event(apm_event_t
*event
, apm_eventinfo_t
*info
)
755 struct apm_bios_call call
;
757 call
.func
= APM_FUNC_GET_EVENT
;
758 call
.ebx
= call
.ecx
= 0;
760 if (apm_bios_call(&call
))
764 if (apm_info
.connection_version
< 0x0102)
765 *info
= ~0; /* indicate info not valid */
772 * set_power_state - set the power management state
773 * @what: which items to transition
774 * @state: state to transition to
776 * Request an APM change of state for one or more system devices. The
777 * processor state must be transitioned last of all. what holds the
778 * class of device in the upper byte and the device number (0xFF for
779 * all) for the object to be transitioned.
781 * The state holds the state to transition to, which may in fact
782 * be an acceptance of a BIOS requested state change.
785 static int set_power_state(u_short what
, u_short state
)
790 if (apm_bios_call_simple(APM_FUNC_SET_STATE
, what
, state
, &eax
, &err
))
796 * set_system_power_state - set system wide power state
797 * @state: which state to enter
799 * Transition the entire system into a new APM power state.
802 static int set_system_power_state(u_short state
)
804 return set_power_state(APM_DEVICE_ALL
, state
);
808 * apm_do_idle - perform power saving
810 * This function notifies the BIOS that the processor is (in the view
811 * of the OS) idle. It returns -1 in the event that the BIOS refuses
812 * to handle the idle request. On a success the function returns 1
813 * if the BIOS did clock slowing or 0 otherwise.
816 static int apm_do_idle(void)
824 polling
= !!(current_thread_info()->status
& TS_POLLING
);
826 current_thread_info()->status
&= ~TS_POLLING
;
828 * TS_POLLING-cleared state must be visible before we
833 if (!need_resched()) {
835 ret
= apm_bios_call_simple(APM_FUNC_IDLE
, 0, 0, &eax
, &err
);
838 current_thread_info()->status
|= TS_POLLING
;
844 static unsigned long t
;
846 /* This always fails on some SMP boards running UP kernels.
847 * Only report the failure the first 5 times.
850 printk(KERN_DEBUG
"apm_do_idle failed (%d)\n", err
);
855 clock_slowed
= (apm_info
.bios
.flags
& APM_IDLE_SLOWS_CLOCK
) != 0;
860 * apm_do_busy - inform the BIOS the CPU is busy
862 * Request that the BIOS brings the CPU back to full performance.
865 static void apm_do_busy(void)
870 if (clock_slowed
|| ALWAYS_CALL_BUSY
) {
871 (void)apm_bios_call_simple(APM_FUNC_BUSY
, 0, 0, &dummy
, &err
);
877 * If no process has really been interested in
878 * the CPU for some time, we want to call BIOS
879 * power management - we probably want
882 #define IDLE_CALC_LIMIT (HZ * 100)
883 #define IDLE_LEAKY_MAX 16
885 static void (*original_pm_idle
)(void) __read_mostly
;
888 * apm_cpu_idle - cpu idling for APM capable Linux
890 * This is the idling function the kernel executes when APM is available. It
891 * tries to do BIOS powermanagement based on the average system idle time.
892 * Furthermore it calls the system default idle routine.
895 static void apm_cpu_idle(void)
897 static int use_apm_idle
; /* = 0 */
898 static unsigned int last_jiffies
; /* = 0 */
899 static unsigned int last_stime
; /* = 0 */
901 int apm_idle_done
= 0;
902 unsigned int jiffies_since_last_check
= jiffies
- last_jiffies
;
906 if (jiffies_since_last_check
> IDLE_CALC_LIMIT
) {
908 last_jiffies
= jiffies
;
909 last_stime
= current
->stime
;
910 } else if (jiffies_since_last_check
> idle_period
) {
911 unsigned int idle_percentage
;
913 idle_percentage
= current
->stime
- last_stime
;
914 idle_percentage
*= 100;
915 idle_percentage
/= jiffies_since_last_check
;
916 use_apm_idle
= (idle_percentage
> idle_threshold
);
917 if (apm_info
.forbid_idle
)
919 last_jiffies
= jiffies
;
920 last_stime
= current
->stime
;
923 bucket
= IDLE_LEAKY_MAX
;
925 while (!need_resched()) {
930 switch (apm_do_idle()) {
935 bucket
= IDLE_LEAKY_MAX
;
946 default: /* BIOS refused */
950 if (original_pm_idle
)
955 jiffies_since_last_check
= jiffies
- last_jiffies
;
956 if (jiffies_since_last_check
> idle_period
)
967 * apm_power_off - ask the BIOS to power off
969 * Handle the power off sequence. This is the one piece of code we
970 * will execute even on SMP machines. In order to deal with BIOS
971 * bugs we support real mode APM BIOS power off calls. We also make
972 * the SMP call on CPU0 as some systems will only honour this call
973 * on their first cpu.
976 static void apm_power_off(void)
978 unsigned char po_bios_call
[] = {
979 0xb8, 0x00, 0x10, /* movw $0x1000,ax */
980 0x8e, 0xd0, /* movw ax,ss */
981 0xbc, 0x00, 0xf0, /* movw $0xf000,sp */
982 0xb8, 0x07, 0x53, /* movw $0x5307,ax */
983 0xbb, 0x01, 0x00, /* movw $0x0001,bx */
984 0xb9, 0x03, 0x00, /* movw $0x0003,cx */
985 0xcd, 0x15 /* int $0x15 */
988 /* Some bioses don't like being called from CPU != 0 */
989 if (apm_info
.realmode_power_off
) {
990 set_cpus_allowed_ptr(current
, cpumask_of(0));
991 machine_real_restart(po_bios_call
, sizeof(po_bios_call
));
993 (void)set_system_power_state(APM_STATE_OFF
);
997 #ifdef CONFIG_APM_DO_ENABLE
1000 * apm_enable_power_management - enable BIOS APM power management
1001 * @enable: enable yes/no
1003 * Enable or disable the APM BIOS power services.
1006 static int apm_enable_power_management(int enable
)
1011 if ((enable
== 0) && (apm_info
.bios
.flags
& APM_BIOS_DISENGAGED
))
1012 return APM_NOT_ENGAGED
;
1013 if (apm_bios_call_simple(APM_FUNC_ENABLE_PM
, APM_DEVICE_BALL
,
1014 enable
, &eax
, &err
))
1017 apm_info
.bios
.flags
&= ~APM_BIOS_DISABLED
;
1019 apm_info
.bios
.flags
|= APM_BIOS_DISABLED
;
1025 * apm_get_power_status - get current power state
1026 * @status: returned status
1027 * @bat: battery info
1028 * @life: estimated life
1030 * Obtain the current power status from the APM BIOS. We return a
1031 * status which gives the rough battery status, and current power
1032 * source. The bat value returned give an estimate as a percentage
1033 * of life and a status value for the battery. The estimated life
1034 * if reported is a lifetime in secodnds/minutes at current powwer
1038 static int apm_get_power_status(u_short
*status
, u_short
*bat
, u_short
*life
)
1040 struct apm_bios_call call
;
1042 call
.func
= APM_FUNC_GET_STATUS
;
1043 call
.ebx
= APM_DEVICE_ALL
;
1046 if (apm_info
.get_power_status_broken
)
1047 return APM_32_UNSUPPORTED
;
1048 if (apm_bios_call(&call
))
1052 if (apm_info
.get_power_status_swabinminutes
) {
1053 *life
= swab16((u16
)call
.edx
);
1061 static int apm_get_battery_status(u_short which
, u_short
*status
,
1062 u_short
*bat
, u_short
*life
, u_short
*nbat
)
1070 if (apm_info
.connection_version
< 0x0102) {
1071 /* pretend we only have one battery. */
1073 return APM_BAD_DEVICE
;
1075 return apm_get_power_status(status
, bat
, life
);
1078 if (apm_bios_call(APM_FUNC_GET_STATUS
, (0x8000 | (which
)), 0, &eax
,
1079 &ebx
, &ecx
, &edx
, &esi
))
1080 return (eax
>> 8) & 0xff;
1090 * apm_engage_power_management - enable PM on a device
1091 * @device: identity of device
1094 * Activate or deactive power management on either a specific device
1095 * or the entire system (%APM_DEVICE_ALL).
1098 static int apm_engage_power_management(u_short device
, int enable
)
1103 if ((enable
== 0) && (device
== APM_DEVICE_ALL
)
1104 && (apm_info
.bios
.flags
& APM_BIOS_DISABLED
))
1105 return APM_DISABLED
;
1106 if (apm_bios_call_simple(APM_FUNC_ENGAGE_PM
, device
, enable
,
1109 if (device
== APM_DEVICE_ALL
) {
1111 apm_info
.bios
.flags
&= ~APM_BIOS_DISENGAGED
;
1113 apm_info
.bios
.flags
|= APM_BIOS_DISENGAGED
;
1118 #if defined(CONFIG_APM_DISPLAY_BLANK) && defined(CONFIG_VT)
1121 * apm_console_blank - blank the display
1124 * Attempt to blank the console, firstly by blanking just video device
1125 * zero, and if that fails (some BIOSes don't support it) then it blanks
1126 * all video devices. Typically the BIOS will do laptop backlight and
1127 * monitor powerdown for us.
1130 static int apm_console_blank(int blank
)
1132 int error
= APM_NOT_ENGAGED
; /* silence gcc */
1135 static const u_short dev
[3] = { 0x100, 0x1FF, 0x101 };
1137 state
= blank
? APM_STATE_STANDBY
: APM_STATE_READY
;
1139 for (i
= 0; i
< ARRAY_SIZE(dev
); i
++) {
1140 error
= set_power_state(dev
[i
], state
);
1142 if ((error
== APM_SUCCESS
) || (error
== APM_NO_ERROR
))
1145 if (error
== APM_NOT_ENGAGED
)
1149 if (error
== APM_NOT_ENGAGED
) {
1153 eng_error
= apm_engage_power_management(APM_DEVICE_ALL
, 1);
1155 apm_error("set display", error
);
1156 apm_error("engage interface", eng_error
);
1159 return apm_console_blank(blank
);
1162 apm_error("set display", error
);
1167 static int queue_empty(struct apm_user
*as
)
1169 return as
->event_head
== as
->event_tail
;
1172 static apm_event_t
get_queued_event(struct apm_user
*as
)
1174 if (++as
->event_tail
>= APM_MAX_EVENTS
)
1176 return as
->events
[as
->event_tail
];
1179 static void queue_event(apm_event_t event
, struct apm_user
*sender
)
1181 struct apm_user
*as
;
1183 spin_lock(&user_list_lock
);
1184 if (user_list
== NULL
)
1186 for (as
= user_list
; as
!= NULL
; as
= as
->next
) {
1187 if ((as
== sender
) || (!as
->reader
))
1189 if (++as
->event_head
>= APM_MAX_EVENTS
)
1192 if (as
->event_head
== as
->event_tail
) {
1193 static int notified
;
1195 if (notified
++ == 0)
1196 printk(KERN_ERR
"apm: an event queue overflowed\n");
1197 if (++as
->event_tail
>= APM_MAX_EVENTS
)
1200 as
->events
[as
->event_head
] = event
;
1201 if (!as
->suser
|| !as
->writer
)
1204 case APM_SYS_SUSPEND
:
1205 case APM_USER_SUSPEND
:
1206 as
->suspends_pending
++;
1210 case APM_SYS_STANDBY
:
1211 case APM_USER_STANDBY
:
1212 as
->standbys_pending
++;
1217 wake_up_interruptible(&apm_waitqueue
);
1219 spin_unlock(&user_list_lock
);
1222 static void reinit_timer(void)
1224 #ifdef INIT_TIMER_AFTER_SUSPEND
1225 unsigned long flags
;
1227 spin_lock_irqsave(&i8253_lock
, flags
);
1228 /* set the clock to HZ */
1229 outb_pit(0x34, PIT_MODE
); /* binary, mode 2, LSB/MSB, ch 0 */
1231 outb_pit(LATCH
& 0xff, PIT_CH0
); /* LSB */
1233 outb_pit(LATCH
>> 8, PIT_CH0
); /* MSB */
1235 spin_unlock_irqrestore(&i8253_lock
, flags
);
1239 static int suspend(int vetoable
)
1242 struct apm_user
*as
;
1244 dpm_suspend_start(PMSG_SUSPEND
);
1246 dpm_suspend_noirq(PMSG_SUSPEND
);
1248 local_irq_disable();
1249 sysdev_suspend(PMSG_SUSPEND
);
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_noirq(PMSG_RESUME
);
1272 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_noirq(PMSG_SUSPEND
);
1290 local_irq_disable();
1291 sysdev_suspend(PMSG_SUSPEND
);
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_noirq(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 printk(KERN_ERR
"apm: %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 unsigned int 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 POLLIN
| POLLRDNORM
;
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
:
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)
1545 case APM_IOC_SUSPEND
:
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) {
1556 as
->suspend_wait
= 1;
1557 wait_event_interruptible(apm_suspend_waitqueue
,
1558 as
->suspend_wait
== 0);
1559 ret
= as
->suspend_result
;
1569 static int do_release(struct inode
*inode
, struct file
*filp
)
1571 struct apm_user
*as
;
1573 as
= filp
->private_data
;
1574 if (check_apm_user(as
, "release"))
1576 filp
->private_data
= NULL
;
1577 if (as
->standbys_pending
> 0) {
1578 standbys_pending
-= as
->standbys_pending
;
1579 if (standbys_pending
<= 0)
1582 if (as
->suspends_pending
> 0) {
1583 suspends_pending
-= as
->suspends_pending
;
1584 if (suspends_pending
<= 0)
1587 spin_lock(&user_list_lock
);
1588 if (user_list
== as
)
1589 user_list
= as
->next
;
1591 struct apm_user
*as1
;
1593 for (as1
= user_list
;
1594 (as1
!= NULL
) && (as1
->next
!= as
);
1598 printk(KERN_ERR
"apm: filp not in user list\n");
1600 as1
->next
= as
->next
;
1602 spin_unlock(&user_list_lock
);
1607 static int do_open(struct inode
*inode
, struct file
*filp
)
1609 struct apm_user
*as
;
1612 as
= kmalloc(sizeof(*as
), GFP_KERNEL
);
1614 printk(KERN_ERR
"apm: cannot allocate struct of size %d bytes\n",
1619 as
->magic
= APM_BIOS_MAGIC
;
1620 as
->event_tail
= as
->event_head
= 0;
1621 as
->suspends_pending
= as
->standbys_pending
= 0;
1622 as
->suspends_read
= as
->standbys_read
= 0;
1624 * XXX - this is a tiny bit broken, when we consider BSD
1625 * process accounting. If the device is opened by root, we
1626 * instantly flag that we used superuser privs. Who knows,
1627 * we might close the device immediately without doing a
1628 * privileged operation -- cevans
1630 as
->suser
= capable(CAP_SYS_ADMIN
);
1631 as
->writer
= (filp
->f_mode
& FMODE_WRITE
) == FMODE_WRITE
;
1632 as
->reader
= (filp
->f_mode
& FMODE_READ
) == FMODE_READ
;
1633 spin_lock(&user_list_lock
);
1634 as
->next
= user_list
;
1636 spin_unlock(&user_list_lock
);
1637 filp
->private_data
= as
;
1642 static int proc_apm_show(struct seq_file
*m
, void *v
)
1648 unsigned short ac_line_status
= 0xff;
1649 unsigned short battery_status
= 0xff;
1650 unsigned short battery_flag
= 0xff;
1651 int percentage
= -1;
1652 int time_units
= -1;
1655 if ((num_online_cpus() == 1) &&
1656 !(error
= apm_get_power_status(&bx
, &cx
, &dx
))) {
1657 ac_line_status
= (bx
>> 8) & 0xff;
1658 battery_status
= bx
& 0xff;
1659 if ((cx
& 0xff) != 0xff)
1660 percentage
= cx
& 0xff;
1662 if (apm_info
.connection_version
> 0x100) {
1663 battery_flag
= (cx
>> 8) & 0xff;
1665 units
= (dx
& 0x8000) ? "min" : "sec";
1666 time_units
= dx
& 0x7fff;
1670 /* Arguments, with symbols from linux/apm_bios.h. Information is
1671 from the Get Power Status (0x0a) call unless otherwise noted.
1673 0) Linux driver version (this will change if format changes)
1674 1) APM BIOS Version. Usually 1.0, 1.1 or 1.2.
1675 2) APM flags from APM Installation Check (0x00):
1676 bit 0: APM_16_BIT_SUPPORT
1677 bit 1: APM_32_BIT_SUPPORT
1678 bit 2: APM_IDLE_SLOWS_CLOCK
1679 bit 3: APM_BIOS_DISABLED
1680 bit 4: APM_BIOS_DISENGAGED
1684 0x02: On backup power (BIOS >= 1.1 only)
1691 0x04: Selected battery not present (BIOS >= 1.2 only)
1698 bit 7: No system battery
1700 6) Remaining battery life (percentage of charge):
1703 7) Remaining battery life (time units):
1704 Number of remaining minutes or seconds
1706 8) min = minutes; sec = seconds */
1708 seq_printf(m
, "%s %d.%d 0x%02x 0x%02x 0x%02x 0x%02x %d%% %d %s\n",
1710 (apm_info
.bios
.version
>> 8) & 0xff,
1711 apm_info
.bios
.version
& 0xff,
1712 apm_info
.bios
.flags
,
1722 static int proc_apm_open(struct inode
*inode
, struct file
*file
)
1724 return single_open(file
, proc_apm_show
, NULL
);
1727 static const struct file_operations apm_file_ops
= {
1728 .owner
= THIS_MODULE
,
1729 .open
= proc_apm_open
,
1731 .llseek
= seq_lseek
,
1732 .release
= single_release
,
1735 static int apm(void *unused
)
1745 * This is to avoid random crashes at boot time during initialization
1746 * on SMP systems in case of "apm=power-off" mode. Seen on ASUS A7M266D.
1747 * Some bioses don't like being called from CPU != 0.
1748 * Method suggested by Ingo Molnar.
1750 set_cpus_allowed_ptr(current
, cpumask_of(0));
1751 BUG_ON(smp_processor_id() != 0);
1753 if (apm_info
.connection_version
== 0) {
1754 apm_info
.connection_version
= apm_info
.bios
.version
;
1755 if (apm_info
.connection_version
> 0x100) {
1757 * We only support BIOSs up to version 1.2
1759 if (apm_info
.connection_version
> 0x0102)
1760 apm_info
.connection_version
= 0x0102;
1761 error
= apm_driver_version(&apm_info
.connection_version
);
1762 if (error
!= APM_SUCCESS
) {
1763 apm_error("driver version", error
);
1764 /* Fall back to an APM 1.0 connection. */
1765 apm_info
.connection_version
= 0x100;
1771 printk(KERN_INFO
"apm: Connection version %d.%d\n",
1772 (apm_info
.connection_version
>> 8) & 0xff,
1773 apm_info
.connection_version
& 0xff);
1775 #ifdef CONFIG_APM_DO_ENABLE
1776 if (apm_info
.bios
.flags
& APM_BIOS_DISABLED
) {
1778 * This call causes my NEC UltraLite Versa 33/C to hang if it
1779 * is booted with PM disabled but not in the docking station.
1782 error
= apm_enable_power_management(1);
1784 apm_error("enable power management", error
);
1790 if ((apm_info
.bios
.flags
& APM_BIOS_DISENGAGED
)
1791 && (apm_info
.connection_version
> 0x0100)) {
1792 error
= apm_engage_power_management(APM_DEVICE_ALL
, 1);
1794 apm_error("engage power management", error
);
1799 if (debug
&& (num_online_cpus() == 1 || smp
)) {
1800 error
= apm_get_power_status(&bx
, &cx
, &dx
);
1802 printk(KERN_INFO
"apm: power status not available\n");
1804 switch ((bx
>> 8) & 0xff) {
1806 power_stat
= "off line";
1809 power_stat
= "on line";
1812 power_stat
= "on backup power";
1815 power_stat
= "unknown";
1818 switch (bx
& 0xff) {
1826 bat_stat
= "critical";
1829 bat_stat
= "charging";
1832 bat_stat
= "unknown";
1836 "apm: AC %s, battery status %s, battery life ",
1837 power_stat
, bat_stat
);
1838 if ((cx
& 0xff) == 0xff)
1839 printk("unknown\n");
1841 printk("%d%%\n", cx
& 0xff);
1842 if (apm_info
.connection_version
> 0x100) {
1844 "apm: battery flag 0x%02x, battery life ",
1847 printk("unknown\n");
1849 printk("%d %s\n", dx
& 0x7fff,
1851 "minutes" : "seconds");
1856 /* Install our power off handler.. */
1858 pm_power_off
= apm_power_off
;
1860 if (num_online_cpus() == 1 || smp
) {
1861 #if defined(CONFIG_APM_DISPLAY_BLANK) && defined(CONFIG_VT)
1862 console_blank_hook
= apm_console_blank
;
1865 #if defined(CONFIG_APM_DISPLAY_BLANK) && defined(CONFIG_VT)
1866 console_blank_hook
= NULL
;
1874 static int __init
apm_setup(char *str
)
1878 while ((str
!= NULL
) && (*str
!= '\0')) {
1879 if (strncmp(str
, "off", 3) == 0)
1881 if (strncmp(str
, "on", 2) == 0)
1883 if ((strncmp(str
, "bounce-interval=", 16) == 0) ||
1884 (strncmp(str
, "bounce_interval=", 16) == 0))
1885 bounce_interval
= simple_strtol(str
+ 16, NULL
, 0);
1886 if ((strncmp(str
, "idle-threshold=", 15) == 0) ||
1887 (strncmp(str
, "idle_threshold=", 15) == 0))
1888 idle_threshold
= simple_strtol(str
+ 15, NULL
, 0);
1889 if ((strncmp(str
, "idle-period=", 12) == 0) ||
1890 (strncmp(str
, "idle_period=", 12) == 0))
1891 idle_period
= simple_strtol(str
+ 12, NULL
, 0);
1892 invert
= (strncmp(str
, "no-", 3) == 0) ||
1893 (strncmp(str
, "no_", 3) == 0);
1896 if (strncmp(str
, "debug", 5) == 0)
1898 if ((strncmp(str
, "power-off", 9) == 0) ||
1899 (strncmp(str
, "power_off", 9) == 0))
1900 power_off
= !invert
;
1901 if (strncmp(str
, "smp", 3) == 0) {
1903 idle_threshold
= 100;
1905 if ((strncmp(str
, "allow-ints", 10) == 0) ||
1906 (strncmp(str
, "allow_ints", 10) == 0))
1907 apm_info
.allow_ints
= !invert
;
1908 if ((strncmp(str
, "broken-psr", 10) == 0) ||
1909 (strncmp(str
, "broken_psr", 10) == 0))
1910 apm_info
.get_power_status_broken
= !invert
;
1911 if ((strncmp(str
, "realmode-power-off", 18) == 0) ||
1912 (strncmp(str
, "realmode_power_off", 18) == 0))
1913 apm_info
.realmode_power_off
= !invert
;
1914 str
= strchr(str
, ',');
1916 str
+= strspn(str
, ", \t");
1921 __setup("apm=", apm_setup
);
1924 static const struct file_operations apm_bios_fops
= {
1925 .owner
= THIS_MODULE
,
1928 .unlocked_ioctl
= do_ioctl
,
1930 .release
= do_release
,
1933 static struct miscdevice apm_device
= {
1940 /* Simple "print if true" callback */
1941 static int __init
print_if_true(const struct dmi_system_id
*d
)
1943 printk("%s\n", d
->ident
);
1948 * Some Bioses enable the PS/2 mouse (touchpad) at resume, even if it was
1949 * disabled before the suspend. Linux used to get terribly confused by that.
1951 static int __init
broken_ps2_resume(const struct dmi_system_id
*d
)
1953 printk(KERN_INFO
"%s machine detected. Mousepad Resume Bug "
1954 "workaround hopefully not needed.\n", d
->ident
);
1958 /* Some bioses have a broken protected mode poweroff and need to use realmode */
1959 static int __init
set_realmode_power_off(const struct dmi_system_id
*d
)
1961 if (apm_info
.realmode_power_off
== 0) {
1962 apm_info
.realmode_power_off
= 1;
1963 printk(KERN_INFO
"%s bios detected. "
1964 "Using realmode poweroff only.\n", d
->ident
);
1969 /* Some laptops require interrupts to be enabled during APM calls */
1970 static int __init
set_apm_ints(const struct dmi_system_id
*d
)
1972 if (apm_info
.allow_ints
== 0) {
1973 apm_info
.allow_ints
= 1;
1974 printk(KERN_INFO
"%s machine detected. "
1975 "Enabling interrupts during APM calls.\n", d
->ident
);
1980 /* Some APM bioses corrupt memory or just plain do not work */
1981 static int __init
apm_is_horked(const struct dmi_system_id
*d
)
1983 if (apm_info
.disabled
== 0) {
1984 apm_info
.disabled
= 1;
1985 printk(KERN_INFO
"%s machine detected. "
1986 "Disabling APM.\n", d
->ident
);
1991 static int __init
apm_is_horked_d850md(const struct dmi_system_id
*d
)
1993 if (apm_info
.disabled
== 0) {
1994 apm_info
.disabled
= 1;
1995 printk(KERN_INFO
"%s machine detected. "
1996 "Disabling APM.\n", d
->ident
);
1997 printk(KERN_INFO
"This bug is fixed in bios P15 which is available for \n");
1998 printk(KERN_INFO
"download from support.intel.com \n");
2003 /* Some APM bioses hang on APM idle calls */
2004 static int __init
apm_likes_to_melt(const struct dmi_system_id
*d
)
2006 if (apm_info
.forbid_idle
== 0) {
2007 apm_info
.forbid_idle
= 1;
2008 printk(KERN_INFO
"%s machine detected. "
2009 "Disabling APM idle calls.\n", d
->ident
);
2015 * Check for clue free BIOS implementations who use
2016 * the following QA technique
2018 * [ Write BIOS Code ]<------
2020 * < Does it Compile >----N--
2022 * < Does it Boot Win98 >-N--
2026 * Phoenix A04 08/24/2000 is known bad (Dell Inspiron 5000e)
2027 * Phoenix A07 09/29/2000 is known good (Dell Inspiron 5000)
2029 static int __init
broken_apm_power(const struct dmi_system_id
*d
)
2031 apm_info
.get_power_status_broken
= 1;
2032 printk(KERN_WARNING
"BIOS strings suggest APM bugs, "
2033 "disabling power status reporting.\n");
2038 * This bios swaps the APM minute reporting bytes over (Many sony laptops
2039 * have this problem).
2041 static int __init
swab_apm_power_in_minutes(const struct dmi_system_id
*d
)
2043 apm_info
.get_power_status_swabinminutes
= 1;
2044 printk(KERN_WARNING
"BIOS strings suggest APM reports battery life "
2045 "in minutes and wrong byte order.\n");
2049 static struct dmi_system_id __initdata apm_dmi_table
[] = {
2052 KERN_WARNING
"IBM T23 - BIOS 1.03b+ and controller firmware 1.02+ may be needed for Linux APM.",
2053 { DMI_MATCH(DMI_SYS_VENDOR
, "IBM"),
2054 DMI_MATCH(DMI_BIOS_VERSION
, "1AET38WW (1.01b)"), },
2056 { /* Handle problems with APM on the C600 */
2057 broken_ps2_resume
, "Dell Latitude C600",
2058 { DMI_MATCH(DMI_SYS_VENDOR
, "Dell"),
2059 DMI_MATCH(DMI_PRODUCT_NAME
, "Latitude C600"), },
2061 { /* Allow interrupts during suspend on Dell Latitude laptops*/
2062 set_apm_ints
, "Dell Latitude",
2063 { DMI_MATCH(DMI_SYS_VENDOR
, "Dell Computer Corporation"),
2064 DMI_MATCH(DMI_PRODUCT_NAME
, "Latitude C510"), }
2067 apm_is_horked
, "Dell Inspiron 2500",
2068 { DMI_MATCH(DMI_SYS_VENDOR
, "Dell Computer Corporation"),
2069 DMI_MATCH(DMI_PRODUCT_NAME
, "Inspiron 2500"),
2070 DMI_MATCH(DMI_BIOS_VENDOR
, "Phoenix Technologies LTD"),
2071 DMI_MATCH(DMI_BIOS_VERSION
, "A11"), },
2073 { /* Allow interrupts during suspend on Dell Inspiron laptops*/
2074 set_apm_ints
, "Dell Inspiron", {
2075 DMI_MATCH(DMI_SYS_VENDOR
, "Dell Computer Corporation"),
2076 DMI_MATCH(DMI_PRODUCT_NAME
, "Inspiron 4000"), },
2078 { /* Handle problems with APM on Inspiron 5000e */
2079 broken_apm_power
, "Dell Inspiron 5000e",
2080 { DMI_MATCH(DMI_BIOS_VENDOR
, "Phoenix Technologies LTD"),
2081 DMI_MATCH(DMI_BIOS_VERSION
, "A04"),
2082 DMI_MATCH(DMI_BIOS_DATE
, "08/24/2000"), },
2084 { /* Handle problems with APM on Inspiron 2500 */
2085 broken_apm_power
, "Dell Inspiron 2500",
2086 { DMI_MATCH(DMI_BIOS_VENDOR
, "Phoenix Technologies LTD"),
2087 DMI_MATCH(DMI_BIOS_VERSION
, "A12"),
2088 DMI_MATCH(DMI_BIOS_DATE
, "02/04/2002"), },
2091 apm_is_horked
, "Dell Dimension 4100",
2092 { DMI_MATCH(DMI_SYS_VENDOR
, "Dell Computer Corporation"),
2093 DMI_MATCH(DMI_PRODUCT_NAME
, "XPS-Z"),
2094 DMI_MATCH(DMI_BIOS_VENDOR
, "Intel Corp."),
2095 DMI_MATCH(DMI_BIOS_VERSION
, "A11"), },
2097 { /* Allow interrupts during suspend on Compaq Laptops*/
2098 set_apm_ints
, "Compaq 12XL125",
2099 { DMI_MATCH(DMI_SYS_VENDOR
, "Compaq"),
2100 DMI_MATCH(DMI_PRODUCT_NAME
, "Compaq PC"),
2101 DMI_MATCH(DMI_BIOS_VENDOR
, "Phoenix Technologies LTD"),
2102 DMI_MATCH(DMI_BIOS_VERSION
, "4.06"), },
2104 { /* Allow interrupts during APM or the clock goes slow */
2105 set_apm_ints
, "ASUSTeK",
2106 { DMI_MATCH(DMI_SYS_VENDOR
, "ASUSTeK Computer Inc."),
2107 DMI_MATCH(DMI_PRODUCT_NAME
, "L8400K series Notebook PC"), },
2109 { /* APM blows on shutdown */
2110 apm_is_horked
, "ABIT KX7-333[R]",
2111 { DMI_MATCH(DMI_BOARD_VENDOR
, "ABIT"),
2112 DMI_MATCH(DMI_BOARD_NAME
, "VT8367-8233A (KX7-333[R])"), },
2115 apm_is_horked
, "Trigem Delhi3",
2116 { DMI_MATCH(DMI_SYS_VENDOR
, "TriGem Computer, Inc"),
2117 DMI_MATCH(DMI_PRODUCT_NAME
, "Delhi3"), },
2120 apm_is_horked
, "Fujitsu-Siemens",
2121 { DMI_MATCH(DMI_BIOS_VENDOR
, "hoenix/FUJITSU SIEMENS"),
2122 DMI_MATCH(DMI_BIOS_VERSION
, "Version1.01"), },
2125 apm_is_horked_d850md
, "Intel D850MD",
2126 { DMI_MATCH(DMI_BIOS_VENDOR
, "Intel Corp."),
2127 DMI_MATCH(DMI_BIOS_VERSION
, "MV85010A.86A.0016.P07.0201251536"), },
2130 apm_is_horked
, "Intel D810EMO",
2131 { DMI_MATCH(DMI_BIOS_VENDOR
, "Intel Corp."),
2132 DMI_MATCH(DMI_BIOS_VERSION
, "MO81010A.86A.0008.P04.0004170800"), },
2135 apm_is_horked
, "Dell XPS-Z",
2136 { DMI_MATCH(DMI_BIOS_VENDOR
, "Intel Corp."),
2137 DMI_MATCH(DMI_BIOS_VERSION
, "A11"),
2138 DMI_MATCH(DMI_PRODUCT_NAME
, "XPS-Z"), },
2141 apm_is_horked
, "Sharp PC-PJ/AX",
2142 { DMI_MATCH(DMI_SYS_VENDOR
, "SHARP"),
2143 DMI_MATCH(DMI_PRODUCT_NAME
, "PC-PJ/AX"),
2144 DMI_MATCH(DMI_BIOS_VENDOR
, "SystemSoft"),
2145 DMI_MATCH(DMI_BIOS_VERSION
, "Version R2.08"), },
2148 apm_is_horked
, "Dell Inspiron 2500",
2149 { DMI_MATCH(DMI_SYS_VENDOR
, "Dell Computer Corporation"),
2150 DMI_MATCH(DMI_PRODUCT_NAME
, "Inspiron 2500"),
2151 DMI_MATCH(DMI_BIOS_VENDOR
, "Phoenix Technologies LTD"),
2152 DMI_MATCH(DMI_BIOS_VERSION
, "A11"), },
2154 { /* APM idle hangs */
2155 apm_likes_to_melt
, "Jabil AMD",
2156 { DMI_MATCH(DMI_BIOS_VENDOR
, "American Megatrends Inc."),
2157 DMI_MATCH(DMI_BIOS_VERSION
, "0AASNP06"), },
2159 { /* APM idle hangs */
2160 apm_likes_to_melt
, "AMI Bios",
2161 { DMI_MATCH(DMI_BIOS_VENDOR
, "American Megatrends Inc."),
2162 DMI_MATCH(DMI_BIOS_VERSION
, "0AASNP05"), },
2164 { /* Handle problems with APM on Sony Vaio PCG-N505X(DE) */
2165 swab_apm_power_in_minutes
, "Sony VAIO",
2166 { DMI_MATCH(DMI_BIOS_VENDOR
, "Phoenix Technologies LTD"),
2167 DMI_MATCH(DMI_BIOS_VERSION
, "R0206H"),
2168 DMI_MATCH(DMI_BIOS_DATE
, "08/23/99"), },
2170 { /* Handle problems with APM on Sony Vaio PCG-N505VX */
2171 swab_apm_power_in_minutes
, "Sony VAIO",
2172 { DMI_MATCH(DMI_BIOS_VENDOR
, "Phoenix Technologies LTD"),
2173 DMI_MATCH(DMI_BIOS_VERSION
, "W2K06H0"),
2174 DMI_MATCH(DMI_BIOS_DATE
, "02/03/00"), },
2176 { /* Handle problems with APM on Sony Vaio PCG-XG29 */
2177 swab_apm_power_in_minutes
, "Sony VAIO",
2178 { DMI_MATCH(DMI_BIOS_VENDOR
, "Phoenix Technologies LTD"),
2179 DMI_MATCH(DMI_BIOS_VERSION
, "R0117A0"),
2180 DMI_MATCH(DMI_BIOS_DATE
, "04/25/00"), },
2182 { /* Handle problems with APM on Sony Vaio PCG-Z600NE */
2183 swab_apm_power_in_minutes
, "Sony VAIO",
2184 { DMI_MATCH(DMI_BIOS_VENDOR
, "Phoenix Technologies LTD"),
2185 DMI_MATCH(DMI_BIOS_VERSION
, "R0121Z1"),
2186 DMI_MATCH(DMI_BIOS_DATE
, "05/11/00"), },
2188 { /* Handle problems with APM on Sony Vaio PCG-Z600NE */
2189 swab_apm_power_in_minutes
, "Sony VAIO",
2190 { DMI_MATCH(DMI_BIOS_VENDOR
, "Phoenix Technologies LTD"),
2191 DMI_MATCH(DMI_BIOS_VERSION
, "WME01Z1"),
2192 DMI_MATCH(DMI_BIOS_DATE
, "08/11/00"), },
2194 { /* Handle problems with APM on Sony Vaio PCG-Z600LEK(DE) */
2195 swab_apm_power_in_minutes
, "Sony VAIO",
2196 { DMI_MATCH(DMI_BIOS_VENDOR
, "Phoenix Technologies LTD"),
2197 DMI_MATCH(DMI_BIOS_VERSION
, "R0206Z3"),
2198 DMI_MATCH(DMI_BIOS_DATE
, "12/25/00"), },
2200 { /* Handle problems with APM on Sony Vaio PCG-Z505LS */
2201 swab_apm_power_in_minutes
, "Sony VAIO",
2202 { DMI_MATCH(DMI_BIOS_VENDOR
, "Phoenix Technologies LTD"),
2203 DMI_MATCH(DMI_BIOS_VERSION
, "R0203D0"),
2204 DMI_MATCH(DMI_BIOS_DATE
, "05/12/00"), },
2206 { /* Handle problems with APM on Sony Vaio PCG-Z505LS */
2207 swab_apm_power_in_minutes
, "Sony VAIO",
2208 { DMI_MATCH(DMI_BIOS_VENDOR
, "Phoenix Technologies LTD"),
2209 DMI_MATCH(DMI_BIOS_VERSION
, "R0203Z3"),
2210 DMI_MATCH(DMI_BIOS_DATE
, "08/25/00"), },
2212 { /* Handle problems with APM on Sony Vaio PCG-Z505LS (with updated BIOS) */
2213 swab_apm_power_in_minutes
, "Sony VAIO",
2214 { DMI_MATCH(DMI_BIOS_VENDOR
, "Phoenix Technologies LTD"),
2215 DMI_MATCH(DMI_BIOS_VERSION
, "R0209Z3"),
2216 DMI_MATCH(DMI_BIOS_DATE
, "05/12/01"), },
2218 { /* Handle problems with APM on Sony Vaio PCG-F104K */
2219 swab_apm_power_in_minutes
, "Sony VAIO",
2220 { DMI_MATCH(DMI_BIOS_VENDOR
, "Phoenix Technologies LTD"),
2221 DMI_MATCH(DMI_BIOS_VERSION
, "R0204K2"),
2222 DMI_MATCH(DMI_BIOS_DATE
, "08/28/00"), },
2225 { /* Handle problems with APM on Sony Vaio PCG-C1VN/C1VE */
2226 swab_apm_power_in_minutes
, "Sony VAIO",
2227 { DMI_MATCH(DMI_BIOS_VENDOR
, "Phoenix Technologies LTD"),
2228 DMI_MATCH(DMI_BIOS_VERSION
, "R0208P1"),
2229 DMI_MATCH(DMI_BIOS_DATE
, "11/09/00"), },
2231 { /* Handle problems with APM on Sony Vaio PCG-C1VE */
2232 swab_apm_power_in_minutes
, "Sony VAIO",
2233 { DMI_MATCH(DMI_BIOS_VENDOR
, "Phoenix Technologies LTD"),
2234 DMI_MATCH(DMI_BIOS_VERSION
, "R0204P1"),
2235 DMI_MATCH(DMI_BIOS_DATE
, "09/12/00"), },
2237 { /* Handle problems with APM on Sony Vaio PCG-C1VE */
2238 swab_apm_power_in_minutes
, "Sony VAIO",
2239 { DMI_MATCH(DMI_BIOS_VENDOR
, "Phoenix Technologies LTD"),
2240 DMI_MATCH(DMI_BIOS_VERSION
, "WXPO1Z3"),
2241 DMI_MATCH(DMI_BIOS_DATE
, "10/26/01"), },
2243 { /* broken PM poweroff bios */
2244 set_realmode_power_off
, "Award Software v4.60 PGMA",
2245 { DMI_MATCH(DMI_BIOS_VENDOR
, "Award Software International, Inc."),
2246 DMI_MATCH(DMI_BIOS_VERSION
, "4.60 PGMA"),
2247 DMI_MATCH(DMI_BIOS_DATE
, "134526184"), },
2250 /* Generic per vendor APM settings */
2252 { /* Allow interrupts during suspend on IBM laptops */
2253 set_apm_ints
, "IBM",
2254 { DMI_MATCH(DMI_SYS_VENDOR
, "IBM"), },
2261 * Just start the APM thread. We do NOT want to do APM BIOS
2262 * calls from anything but the APM thread, if for no other reason
2263 * than the fact that we don't trust the APM BIOS. This way,
2264 * most common APM BIOS problems that lead to protection errors
2265 * etc will have at least some level of being contained...
2267 * In short, if something bad happens, at least we have a choice
2268 * of just killing the apm thread..
2270 static int __init
apm_init(void)
2272 struct desc_struct
*gdt
;
2275 dmi_check_system(apm_dmi_table
);
2277 if (apm_info
.bios
.version
== 0 || paravirt_enabled() || machine_is_olpc()) {
2278 printk(KERN_INFO
"apm: BIOS not found.\n");
2282 "apm: BIOS version %d.%d Flags 0x%02x (Driver version %s)\n",
2283 ((apm_info
.bios
.version
>> 8) & 0xff),
2284 (apm_info
.bios
.version
& 0xff),
2285 apm_info
.bios
.flags
,
2287 if ((apm_info
.bios
.flags
& APM_32_BIT_SUPPORT
) == 0) {
2288 printk(KERN_INFO
"apm: no 32 bit BIOS support\n");
2293 apm_info
.allow_ints
= 1;
2295 apm_info
.get_power_status_broken
= 1;
2296 if (realmode_power_off
)
2297 apm_info
.realmode_power_off
= 1;
2298 /* User can override, but default is to trust DMI */
2299 if (apm_disabled
!= -1)
2300 apm_info
.disabled
= apm_disabled
;
2303 * Fix for the Compaq Contura 3/25c which reports BIOS version 0.1
2304 * but is reportedly a 1.0 BIOS.
2306 if (apm_info
.bios
.version
== 0x001)
2307 apm_info
.bios
.version
= 0x100;
2309 /* BIOS < 1.2 doesn't set cseg_16_len */
2310 if (apm_info
.bios
.version
< 0x102)
2311 apm_info
.bios
.cseg_16_len
= 0; /* 64k */
2314 printk(KERN_INFO
"apm: entry %x:%x cseg16 %x dseg %x",
2315 apm_info
.bios
.cseg
, apm_info
.bios
.offset
,
2316 apm_info
.bios
.cseg_16
, apm_info
.bios
.dseg
);
2317 if (apm_info
.bios
.version
> 0x100)
2318 printk(" cseg len %x, dseg len %x",
2319 apm_info
.bios
.cseg_len
,
2320 apm_info
.bios
.dseg_len
);
2321 if (apm_info
.bios
.version
> 0x101)
2322 printk(" cseg16 len %x", apm_info
.bios
.cseg_16_len
);
2326 if (apm_info
.disabled
) {
2327 printk(KERN_NOTICE
"apm: disabled on user request.\n");
2330 if ((num_online_cpus() > 1) && !power_off
&& !smp
) {
2331 printk(KERN_NOTICE
"apm: disabled - APM is not SMP safe.\n");
2332 apm_info
.disabled
= 1;
2335 if (pm_flags
& PM_ACPI
) {
2336 printk(KERN_NOTICE
"apm: overridden by ACPI.\n");
2337 apm_info
.disabled
= 1;
2343 * Set up the long jump entry point to the APM BIOS, which is called
2344 * from inline assembly.
2346 apm_bios_entry
.offset
= apm_info
.bios
.offset
;
2347 apm_bios_entry
.segment
= APM_CS
;
2350 * The APM 1.1 BIOS is supposed to provide limit information that it
2351 * recognizes. Many machines do this correctly, but many others do
2352 * not restrict themselves to their claimed limit. When this happens,
2353 * they will cause a segmentation violation in the kernel at boot time.
2354 * Most BIOS's, however, will respect a 64k limit, so we use that.
2356 * Note we only set APM segments on CPU zero, since we pin the APM
2359 gdt
= get_cpu_gdt_table(0);
2360 set_desc_base(&gdt
[APM_CS
>> 3],
2361 (unsigned long)__va((unsigned long)apm_info
.bios
.cseg
<< 4));
2362 set_desc_base(&gdt
[APM_CS_16
>> 3],
2363 (unsigned long)__va((unsigned long)apm_info
.bios
.cseg_16
<< 4));
2364 set_desc_base(&gdt
[APM_DS
>> 3],
2365 (unsigned long)__va((unsigned long)apm_info
.bios
.dseg
<< 4));
2367 proc_create("apm", 0, NULL
, &apm_file_ops
);
2369 kapmd_task
= kthread_create(apm
, NULL
, "kapmd");
2370 if (IS_ERR(kapmd_task
)) {
2371 printk(KERN_ERR
"apm: disabled - Unable to start kernel "
2373 err
= PTR_ERR(kapmd_task
);
2375 remove_proc_entry("apm", NULL
);
2378 wake_up_process(kapmd_task
);
2380 if (num_online_cpus() > 1 && !smp
) {
2382 "apm: disabled - APM is not SMP safe (power off active).\n");
2387 * Note we don't actually care if the misc_device cannot be registered.
2388 * this driver can do its job without it, even if userspace can't
2389 * control it. just log the error
2391 if (misc_register(&apm_device
))
2392 printk(KERN_WARNING
"apm: Could not register misc device.\n");
2395 idle_period
= (idle_period
* HZ
) / 100;
2396 if (idle_threshold
< 100) {
2397 original_pm_idle
= pm_idle
;
2398 pm_idle
= apm_cpu_idle
;
2405 static void __exit
apm_exit(void)
2410 pm_idle
= original_pm_idle
;
2412 * We are about to unload the current idle thread pm callback
2413 * (pm_idle), Wait for all processors to update cached/local
2414 * copies of pm_idle before proceeding.
2418 if (((apm_info
.bios
.flags
& APM_BIOS_DISENGAGED
) == 0)
2419 && (apm_info
.connection_version
> 0x0100)) {
2420 error
= apm_engage_power_management(APM_DEVICE_ALL
, 0);
2422 apm_error("disengage power management", error
);
2424 misc_deregister(&apm_device
);
2425 remove_proc_entry("apm", NULL
);
2427 pm_power_off
= NULL
;
2429 kthread_stop(kapmd_task
);
2432 pm_flags
&= ~PM_APM
;
2435 module_init(apm_init
);
2436 module_exit(apm_exit
);
2438 MODULE_AUTHOR("Stephen Rothwell");
2439 MODULE_DESCRIPTION("Advanced Power Management");
2440 MODULE_LICENSE("GPL");
2441 module_param(debug
, bool, 0644);
2442 MODULE_PARM_DESC(debug
, "Enable debug mode");
2443 module_param(power_off
, bool, 0444);
2444 MODULE_PARM_DESC(power_off
, "Enable power off");
2445 module_param(bounce_interval
, int, 0444);
2446 MODULE_PARM_DESC(bounce_interval
,
2447 "Set the number of ticks to ignore suspend bounces");
2448 module_param(allow_ints
, bool, 0444);
2449 MODULE_PARM_DESC(allow_ints
, "Allow interrupts during BIOS calls");
2450 module_param(broken_psr
, bool, 0444);
2451 MODULE_PARM_DESC(broken_psr
, "BIOS has a broken GetPowerStatus call");
2452 module_param(realmode_power_off
, bool, 0444);
2453 MODULE_PARM_DESC(realmode_power_off
,
2454 "Switch to real mode before powering off");
2455 module_param(idle_threshold
, int, 0444);
2456 MODULE_PARM_DESC(idle_threshold
,
2457 "System idle percentage above which to make APM BIOS idle calls");
2458 module_param(idle_period
, int, 0444);
2459 MODULE_PARM_DESC(idle_period
,
2460 "Period (in sec/100) over which to caculate the idle percentage");
2461 module_param(smp
, bool, 0444);
2462 MODULE_PARM_DESC(smp
,
2463 "Set this to enable APM use on an SMP platform. Use with caution on older systems");
2464 MODULE_ALIAS_MISCDEV(APM_MINOR_DEV
);