1 // SPDX-License-Identifier: GPL-2.0-or-later
3 * APM BIOS driver for Linux
4 * Copyright 1994-2001 Stephen Rothwell (sfr@canb.auug.org.au)
6 * Initial development of this driver was funded by NEC Australia P/L
9 * October 1995, Rik Faith (faith@cs.unc.edu):
10 * Minor enhancements and updates (to the patch set) for 1.3.x
12 * January 1996, Rik Faith (faith@cs.unc.edu):
13 * Make /proc/apm easy to format (bump driver version)
14 * March 1996, Rik Faith (faith@cs.unc.edu):
15 * Prohibit APM BIOS calls unless apm_enabled.
16 * (Thanks to Ulrich Windl <Ulrich.Windl@rz.uni-regensburg.de>)
17 * April 1996, Stephen Rothwell (sfr@canb.auug.org.au)
19 * May 1996, Version 1.2
20 * Feb 1998, Version 1.3
21 * Feb 1998, Version 1.4
22 * Aug 1998, Version 1.5
23 * Sep 1998, Version 1.6
24 * Nov 1998, Version 1.7
25 * Jan 1999, Version 1.8
26 * Jan 1999, Version 1.9
27 * Oct 1999, Version 1.10
28 * Nov 1999, Version 1.11
29 * Jan 2000, Version 1.12
30 * Feb 2000, Version 1.13
31 * Nov 2000, Version 1.14
32 * Oct 2001, Version 1.15
33 * Jan 2002, Version 1.16
34 * Oct 2002, Version 1.16ac
37 * 0.6b: first version in official kernel, Linux 1.3.46
38 * 0.7: changed /proc/apm format, Linux 1.3.58
39 * 0.8: fixed gcc 2.7.[12] compilation problems, Linux 1.3.59
40 * 0.9: only call bios if bios is present, Linux 1.3.72
41 * 1.0: use fixed device number, consolidate /proc/apm into this file,
43 * 1.1: support user-space standby and suspend, power off after system
44 * halted, Linux 1.3.98
45 * 1.2: When resetting RTC after resume, take care so that the time
46 * is only incorrect by 30-60mS (vs. 1S previously) (Gabor J. Toth
47 * <jtoth@princeton.edu>); improve interaction between
48 * screen-blanking and gpm (Stephen Rothwell); Linux 1.99.4
49 * 1.2a:Simple change to stop mysterious bug reports with SMP also added
50 * levels to the printk calls. APM is not defined for SMP machines.
51 * The new replacement for it is, but Linux doesn't yet support this.
52 * Alan Cox Linux 2.1.55
53 * 1.3: Set up a valid data descriptor 0x40 for buggy BIOS's
54 * 1.4: Upgraded to support APM 1.2. Integrated ThinkPad suspend patch by
55 * Dean Gaudet <dgaudet@arctic.org>.
56 * C. Scott Ananian <cananian@alumni.princeton.edu> Linux 2.1.87
57 * 1.5: Fix segment register reloading (in case of bad segments saved
60 * 1.6: Cope with compiler/assembler differences.
61 * Only try to turn off the first display device.
62 * Fix OOPS at power off with no APM BIOS by Jan Echternach
63 * <echter@informatik.uni-rostock.de>
65 * 1.7: Modify driver's cached copy of the disabled/disengaged flags
66 * to reflect current state of APM BIOS.
67 * Chris Rankin <rankinc@bellsouth.net>
68 * Reset interrupt 0 timer to 100Hz after suspend
69 * Chad Miller <cmiller@surfsouth.com>
70 * Add CONFIG_APM_IGNORE_SUSPEND_BOUNCE
71 * Richard Gooch <rgooch@atnf.csiro.au>
72 * Allow boot time disabling of APM
73 * Make boot messages far less verbose by default
76 * 1.8: Add CONFIG_APM_RTC_IS_GMT
77 * Richard Gooch <rgooch@atnf.csiro.au>
78 * change APM_NOINTS to CONFIG_APM_ALLOW_INTS
79 * remove dependency on CONFIG_PROC_FS
81 * 1.9: Fix small typo. <laslo@wodip.opole.pl>
82 * Try to cope with BIOS's that need to have all display
83 * devices blanked and not just the first one.
84 * Ross Paterson <ross@soi.city.ac.uk>
85 * Fix segment limit setting it has always been wrong as
86 * the segments needed to have byte granularity.
87 * Mark a few things __init.
88 * Add hack to allow power off of SMP systems by popular request.
89 * Use CONFIG_SMP instead of __SMP__
90 * Ignore BOUNCES for three seconds.
92 * 1.10: Fix for Thinkpad return code.
93 * Merge 2.2 and 2.3 drivers.
94 * Remove APM dependencies in arch/i386/kernel/process.c
95 * Remove APM dependencies in drivers/char/sysrq.c
96 * Reset time across standby.
97 * Allow more inititialisation on SMP.
98 * Remove CONFIG_APM_POWER_OFF and make it boot time
99 * configurable (default on).
100 * Make debug only a boot time parameter (remove APM_DEBUG).
101 * Try to blank all devices on any error.
102 * 1.11: Remove APM dependencies in drivers/char/console.c
103 * Check nr_running to detect if we are idle (from
104 * Borislav Deianov <borislav@lix.polytechnique.fr>)
105 * Fix for bioses that don't zero the top part of the
106 * entrypoint offset (Mario Sitta <sitta@al.unipmn.it>)
107 * (reported by Panos Katsaloulis <teras@writeme.com>).
108 * Real mode power off patch (Walter Hofmann
109 * <Walter.Hofmann@physik.stud.uni-erlangen.de>).
110 * 1.12: Remove CONFIG_SMP as the compiler will optimize
111 * the code away anyway (smp_num_cpus == 1 in UP)
112 * noted by Artur Skawina <skawina@geocities.com>.
113 * Make power off under SMP work again.
114 * Fix thinko with initial engaging of BIOS.
115 * Make sure power off only happens on CPU 0
116 * (Paul "Rusty" Russell <rusty@rustcorp.com.au>).
117 * Do error notification to user mode if BIOS calls fail.
118 * Move entrypoint offset fix to ...boot/setup.S
119 * where it belongs (Cosmos <gis88564@cis.nctu.edu.tw>).
120 * Remove smp-power-off. SMP users must now specify
121 * "apm=power-off" on the kernel command line. Suggested
122 * by Jim Avera <jima@hal.com>, modified by Alan Cox
123 * <alan@lxorguk.ukuu.org.uk>.
124 * Register the /proc/apm entry even on SMP so that
125 * scripts that check for it before doing power off
126 * work (Jim Avera <jima@hal.com>).
127 * 1.13: Changes for new pm_ interfaces (Andy Henroid
128 * <andy_henroid@yahoo.com>).
129 * Modularize the code.
130 * Fix the Thinkpad (again) :-( (CONFIG_APM_IGNORE_MULTIPLE_SUSPENDS
131 * is now the way life works).
132 * Fix thinko in suspend() (wrong return).
133 * Notify drivers on critical suspend.
134 * Make kapmd absorb more idle time (Pavel Machek <pavel@ucw.cz>
136 * Disable interrupts while we are suspended (Andy Henroid
137 * <andy_henroid@yahoo.com> fixed by sfr).
138 * Make power off work on SMP again (Tony Hoyle
139 * <tmh@magenta-logic.com> and <zlatko@iskon.hr>) modified by sfr.
140 * Remove CONFIG_APM_SUSPEND_BOUNCE. The bounce ignore
141 * interval is now configurable.
142 * 1.14: Make connection version persist across module unload/load.
143 * Enable and engage power management earlier.
144 * Disengage power management on module unload.
145 * Changed to use the sysrq-register hack for registering the
146 * power off function called by magic sysrq based upon discussions
147 * in irc://irc.openprojects.net/#kernelnewbies
148 * (Crutcher Dunnavant <crutcher+kernel@datastacks.com>).
149 * Make CONFIG_APM_REAL_MODE_POWER_OFF run time configurable.
150 * (Arjan van de Ven <arjanv@redhat.com>) modified by sfr.
151 * Work around byte swap bug in one of the Vaio's BIOS's
152 * (Marc Boucher <marc@mbsi.ca>).
153 * Exposed the disable flag to dmi so that we can handle known
154 * broken APM (Alan Cox <alan@lxorguk.ukuu.org.uk>).
155 * 1.14ac: If the BIOS says "I slowed the CPU down" then don't spin
156 * calling it - instead idle. (Alan Cox <alan@lxorguk.ukuu.org.uk>)
157 * If an APM idle fails log it and idle sensibly
158 * 1.15: Don't queue events to clients who open the device O_WRONLY.
159 * Don't expect replies from clients who open the device O_RDONLY.
160 * (Idea from Thomas Hood)
161 * Minor waitqueue cleanups. (John Fremlin <chief@bandits.org>)
162 * 1.16: Fix idle calling. (Andreas Steinmetz <ast@domdv.de> et al.)
163 * Notify listeners of standby or suspend events before notifying
164 * drivers. Return EBUSY to ioctl() if suspend is rejected.
165 * (Russell King <rmk@arm.linux.org.uk> and Thomas Hood)
166 * Ignore first resume after we generate our own resume event
167 * after a suspend (Thomas Hood)
168 * Daemonize now gets rid of our controlling terminal (sfr).
169 * CONFIG_APM_CPU_IDLE now just affects the default value of
170 * idle_threshold (sfr).
171 * Change name of kernel apm daemon (as it no longer idles) (sfr).
172 * 1.16ac: Fix up SMP support somewhat. You can now force SMP on and we
173 * make _all_ APM calls on the CPU#0. Fix unsafe sign bug.
174 * TODO: determine if its "boot CPU" or "CPU0" we want to lock to.
178 * Intel Corporation, Microsoft Corporation. Advanced Power Management
179 * (APM) BIOS Interface Specification, Revision 1.1, September 1993.
180 * Intel Order Number 241704-001. Microsoft Part Number 781-110-X01.
182 * [This document is available free from Intel by calling 800.628.8686 (fax
183 * 916.356.6100) or 800.548.4725; or from
184 * http://www.microsoft.com/whdc/archive/amp_12.mspx It is also
185 * available from Microsoft by calling 206.882.8080.]
188 * Intel Corporation, Microsoft Corporation. Advanced Power Management
189 * (APM) BIOS Interface Specification, Revision 1.2, February 1996.
191 * [This document is available from Microsoft at:
192 * http://www.microsoft.com/whdc/archive/amp_12.mspx]
195 #define pr_fmt(fmt) "apm: " fmt
197 #include <linux/module.h>
199 #include <linux/poll.h>
200 #include <linux/types.h>
201 #include <linux/stddef.h>
202 #include <linux/timer.h>
203 #include <linux/fcntl.h>
204 #include <linux/slab.h>
205 #include <linux/stat.h>
206 #include <linux/proc_fs.h>
207 #include <linux/seq_file.h>
208 #include <linux/miscdevice.h>
209 #include <linux/apm_bios.h>
210 #include <linux/init.h>
211 #include <linux/time.h>
212 #include <linux/sched/signal.h>
213 #include <linux/sched/cputime.h>
214 #include <linux/pm.h>
215 #include <linux/capability.h>
216 #include <linux/device.h>
217 #include <linux/kernel.h>
218 #include <linux/freezer.h>
219 #include <linux/smp.h>
220 #include <linux/dmi.h>
221 #include <linux/suspend.h>
222 #include <linux/kthread.h>
223 #include <linux/jiffies.h>
224 #include <linux/acpi.h>
225 #include <linux/syscore_ops.h>
226 #include <linux/i8253.h>
227 #include <linux/cpuidle.h>
229 #include <linux/uaccess.h>
230 #include <asm/desc.h>
231 #include <asm/olpc.h>
232 #include <asm/paravirt.h>
233 #include <asm/reboot.h>
234 #include <asm/nospec-branch.h>
236 #if defined(CONFIG_APM_DISPLAY_BLANK) && defined(CONFIG_VT)
237 extern int (*console_blank_hook
)(int);
241 * The apm_bios device is one of the misc char devices.
242 * This is its minor number.
244 #define APM_MINOR_DEV 134
247 * Various options can be changed at boot time as follows:
248 * (We allow underscores for compatibility with the modules code)
249 * apm=on/off enable/disable APM
250 * [no-]allow[-_]ints allow interrupts during BIOS calls
251 * [no-]broken[-_]psr BIOS has a broken GetPowerStatus call
252 * [no-]realmode[-_]power[-_]off switch to real mode before
254 * [no-]debug log some debugging messages
255 * [no-]power[-_]off power off on shutdown
256 * [no-]smp Use apm even on an SMP box
257 * bounce[-_]interval=<n> number of ticks to ignore suspend
259 * idle[-_]threshold=<n> System idle percentage above which to
260 * make APM BIOS idle calls. Set it to
262 * idle[-_]period=<n> Period (in 1/100s of a second) over
263 * which the idle percentage is
267 /* KNOWN PROBLEM MACHINES:
269 * U: TI 4000M TravelMate: BIOS is *NOT* APM compliant
270 * [Confirmed by TI representative]
271 * ?: ACER 486DX4/75: uses dseg 0040, in violation of APM specification
272 * [Confirmed by BIOS disassembly]
273 * [This may work now ...]
274 * P: Toshiba 1950S: battery life information only gets updated after resume
275 * P: Midwest Micro Soundbook Elite DX2/66 monochrome: screen blanking
276 * broken in BIOS [Reported by Garst R. Reese <reese@isn.net>]
277 * ?: AcerNote-950: oops on reading /proc/apm - workaround is a WIP
278 * Neale Banks <neale@lowendale.com.au> December 2000
280 * Legend: U = unusable with APM patches
281 * P = partially usable with APM patches
285 * Define as 1 to make the driver always call the APM BIOS busy
286 * routine even if the clock was not reported as slowed by the
287 * idle routine. Otherwise, define as 0.
289 #define ALWAYS_CALL_BUSY 1
292 * Define to make the APM BIOS calls zero all data segment registers (so
293 * that an incorrect BIOS implementation will cause a kernel panic if it
294 * tries to write to arbitrary memory).
296 #define APM_ZERO_SEGS
301 * Define to re-initialize the interrupt 0 timer to 100 Hz after a suspend.
302 * This patched by Chad Miller <cmiller@surfsouth.com>, original code by
303 * David Chen <chen@ctpa04.mit.edu>
305 #undef INIT_TIMER_AFTER_SUSPEND
307 #ifdef INIT_TIMER_AFTER_SUSPEND
308 #include <linux/timex.h>
310 #include <linux/delay.h>
314 * Need to poll the APM BIOS every second
316 #define APM_CHECK_TIMEOUT (HZ)
319 * Ignore suspend events for this amount of time after a resume
321 #define DEFAULT_BOUNCE_INTERVAL (3 * HZ)
324 * Maximum number of events stored
326 #define APM_MAX_EVENTS 20
329 * The per-file APM data
333 struct apm_user
*next
;
334 unsigned int suser
: 1;
335 unsigned int writer
: 1;
336 unsigned int reader
: 1;
337 unsigned int suspend_wait
: 1;
339 int suspends_pending
;
340 int standbys_pending
;
345 apm_event_t events
[APM_MAX_EVENTS
];
349 * The magic number in apm_user
351 #define APM_BIOS_MAGIC 0x4101
354 * idle percentage above which bios idle calls are done
356 #ifdef CONFIG_APM_CPU_IDLE
357 #define DEFAULT_IDLE_THRESHOLD 95
359 #define DEFAULT_IDLE_THRESHOLD 100
361 #define DEFAULT_IDLE_PERIOD (100 / 3)
363 static int apm_cpu_idle(struct cpuidle_device
*dev
,
364 struct cpuidle_driver
*drv
, int index
);
366 static struct cpuidle_driver apm_idle_driver
= {
368 .owner
= THIS_MODULE
,
370 { /* entry 0 is for polling */ },
371 { /* entry 1 is for APM idle */
374 .exit_latency
= 250, /* WAG */
375 .target_residency
= 500, /* WAG */
376 .enter
= &apm_cpu_idle
382 static struct cpuidle_device apm_cpuidle_device
;
388 unsigned long offset
;
389 unsigned short segment
;
391 static int clock_slowed
;
392 static int idle_threshold __read_mostly
= DEFAULT_IDLE_THRESHOLD
;
393 static int idle_period __read_mostly
= DEFAULT_IDLE_PERIOD
;
394 static int suspends_pending
;
395 static int standbys_pending
;
396 static int ignore_sys_suspend
;
397 static int ignore_normal_resume
;
398 static int bounce_interval __read_mostly
= DEFAULT_BOUNCE_INTERVAL
;
400 static bool debug __read_mostly
;
401 static bool smp __read_mostly
;
402 static int apm_disabled
= -1;
404 static bool power_off
;
406 static bool power_off
= 1;
408 static bool realmode_power_off
;
409 #ifdef CONFIG_APM_ALLOW_INTS
410 static bool allow_ints
= 1;
412 static bool allow_ints
;
414 static bool broken_psr
;
416 static DECLARE_WAIT_QUEUE_HEAD(apm_waitqueue
);
417 static DECLARE_WAIT_QUEUE_HEAD(apm_suspend_waitqueue
);
418 static struct apm_user
*user_list
;
419 static DEFINE_SPINLOCK(user_list_lock
);
420 static DEFINE_MUTEX(apm_mutex
);
423 * Set up a segment that references the real mode segment 0x40
424 * that extends up to the end of page zero (that we have reserved).
425 * This is for buggy BIOS's that refer to (real mode) segment 0x40
426 * even though they are called in protected mode.
428 static struct desc_struct bad_bios_desc
= GDT_ENTRY_INIT(0x4092,
429 (unsigned long)__va(0x400UL
), PAGE_SIZE
- 0x400 - 1);
431 static const char driver_version
[] = "1.16ac"; /* no spaces */
433 static struct task_struct
*kapmd_task
;
436 * APM event names taken from the APM 1.2 specification. These are
437 * the message codes that the BIOS uses to tell us about events
439 static const char * const apm_event_name
[] = {
445 "power status change",
450 "system standby resume",
451 "capabilities change"
453 #define NR_APM_EVENT_NAME ARRAY_SIZE(apm_event_name)
455 typedef struct lookup_t
{
461 * The BIOS returns a set of standard error codes in AX when the
465 static const lookup_t error_table
[] = {
466 /* N/A { APM_SUCCESS, "Operation succeeded" }, */
467 { APM_DISABLED
, "Power management disabled" },
468 { APM_CONNECTED
, "Real mode interface already connected" },
469 { APM_NOT_CONNECTED
, "Interface not connected" },
470 { APM_16_CONNECTED
, "16 bit interface already connected" },
471 /* N/A { APM_16_UNSUPPORTED, "16 bit interface not supported" }, */
472 { APM_32_CONNECTED
, "32 bit interface already connected" },
473 { APM_32_UNSUPPORTED
, "32 bit interface not supported" },
474 { APM_BAD_DEVICE
, "Unrecognized device ID" },
475 { APM_BAD_PARAM
, "Parameter out of range" },
476 { APM_NOT_ENGAGED
, "Interface not engaged" },
477 { APM_BAD_FUNCTION
, "Function not supported" },
478 { APM_RESUME_DISABLED
, "Resume timer disabled" },
479 { APM_BAD_STATE
, "Unable to enter requested state" },
480 /* N/A { APM_NO_EVENTS, "No events pending" }, */
481 { APM_NO_ERROR
, "BIOS did not set a return code" },
482 { APM_NOT_PRESENT
, "No APM present" }
484 #define ERROR_COUNT ARRAY_SIZE(error_table)
487 * apm_error - display an APM error
488 * @str: information string
489 * @err: APM BIOS return code
491 * Write a meaningful log entry to the kernel log in the event of
492 * an APM error. Note that this also handles (negative) kernel errors.
495 static void apm_error(char *str
, int err
)
499 for (i
= 0; i
< ERROR_COUNT
; i
++)
500 if (error_table
[i
].key
== err
)
503 pr_notice("%s: %s\n", str
, error_table
[i
].msg
);
505 pr_notice("%s: linux error code %i\n", str
, err
);
507 pr_notice("%s: unknown error code %#2.2x\n",
512 * These are the actual BIOS calls. Depending on APM_ZERO_SEGS and
513 * apm_info.allow_ints, we are being really paranoid here! Not only
514 * are interrupts disabled, but all the segment registers (except SS)
515 * are saved and zeroed this means that if the BIOS tries to reference
516 * any data without explicitly loading the segment registers, the kernel
517 * will fault immediately rather than have some unforeseen circumstances
518 * for the rest of the kernel. And it will be very obvious! :-) Doing
519 * this depends on CS referring to the same physical memory as DS so that
520 * DS can be zeroed before the call. Unfortunately, we can't do anything
521 * about the stack segment/pointer. Also, we tell the compiler that
522 * everything could change.
524 * Also, we KNOW that for the non error case of apm_bios_call, there
525 * is no useful data returned in the low order 8 bits of eax.
528 static inline unsigned long __apm_irq_save(void)
531 local_save_flags(flags
);
532 if (apm_info
.allow_ints
) {
533 if (irqs_disabled_flags(flags
))
541 #define apm_irq_save(flags) \
542 do { flags = __apm_irq_save(); } while (0)
544 static inline void apm_irq_restore(unsigned long flags
)
546 if (irqs_disabled_flags(flags
))
548 else if (irqs_disabled())
553 # define APM_DECL_SEGS \
554 unsigned int saved_fs; unsigned int saved_gs;
555 # define APM_DO_SAVE_SEGS \
556 savesegment(fs, saved_fs); savesegment(gs, saved_gs)
557 # define APM_DO_RESTORE_SEGS \
558 loadsegment(fs, saved_fs); loadsegment(gs, saved_gs)
560 # define APM_DECL_SEGS
561 # define APM_DO_SAVE_SEGS
562 # define APM_DO_RESTORE_SEGS
565 struct apm_bios_call
{
575 /* Error: -ENOMEM, or bits 8-15 of eax */
580 * __apm_bios_call - Make an APM BIOS 32bit call
581 * @_call: pointer to struct apm_bios_call.
583 * Make an APM call using the 32bit protected mode interface. The
584 * caller is responsible for knowing if APM BIOS is configured and
585 * enabled. This call can disable interrupts for a long period of
586 * time on some laptops. The return value is in AH and the carry
587 * flag is loaded into AL. If there is an error, then the error
588 * code is returned in AH (bits 8-15 of eax) and this function
591 * Note: this makes the call on the current CPU.
593 static long __apm_bios_call(void *_call
)
598 struct desc_struct save_desc_40
;
599 struct desc_struct
*gdt
;
600 struct apm_bios_call
*call
= _call
;
604 gdt
= get_cpu_gdt_rw(cpu
);
605 save_desc_40
= gdt
[0x40 / 8];
606 gdt
[0x40 / 8] = bad_bios_desc
;
609 firmware_restrict_branch_speculation_start();
611 apm_bios_call_asm(call
->func
, call
->ebx
, call
->ecx
,
612 &call
->eax
, &call
->ebx
, &call
->ecx
, &call
->edx
,
615 firmware_restrict_branch_speculation_end();
616 apm_irq_restore(flags
);
617 gdt
[0x40 / 8] = save_desc_40
;
620 return call
->eax
& 0xff;
623 /* Run __apm_bios_call or __apm_bios_call_simple on CPU 0 */
624 static int on_cpu0(long (*fn
)(void *), struct apm_bios_call
*call
)
628 /* Don't bother with work_on_cpu in the common case, so we don't
629 * have to worry about OOM or overhead. */
630 if (get_cpu() == 0) {
635 ret
= work_on_cpu(0, fn
, call
);
638 /* work_on_cpu can fail with -ENOMEM */
642 call
->err
= (call
->eax
>> 8) & 0xff;
648 * apm_bios_call - Make an APM BIOS 32bit call (on CPU 0)
649 * @call: the apm_bios_call registers.
651 * If there is an error, it is returned in @call.err.
653 static int apm_bios_call(struct apm_bios_call
*call
)
655 return on_cpu0(__apm_bios_call
, call
);
659 * __apm_bios_call_simple - Make an APM BIOS 32bit call (on CPU 0)
660 * @_call: pointer to struct apm_bios_call.
662 * Make a BIOS call that returns one value only, or just status.
663 * If there is an error, then the error code is returned in AH
664 * (bits 8-15 of eax) and this function returns non-zero (it can
665 * also return -ENOMEM). This is used for simpler BIOS operations.
666 * This call may hold interrupts off for a long time on some laptops.
668 * Note: this makes the call on the current CPU.
670 static long __apm_bios_call_simple(void *_call
)
676 struct desc_struct save_desc_40
;
677 struct desc_struct
*gdt
;
678 struct apm_bios_call
*call
= _call
;
682 gdt
= get_cpu_gdt_rw(cpu
);
683 save_desc_40
= gdt
[0x40 / 8];
684 gdt
[0x40 / 8] = bad_bios_desc
;
687 firmware_restrict_branch_speculation_start();
689 error
= apm_bios_call_simple_asm(call
->func
, call
->ebx
, call
->ecx
,
692 firmware_restrict_branch_speculation_end();
693 apm_irq_restore(flags
);
694 gdt
[0x40 / 8] = save_desc_40
;
700 * apm_bios_call_simple - make a simple APM BIOS 32bit call
701 * @func: APM function to invoke
702 * @ebx_in: EBX register value for BIOS call
703 * @ecx_in: ECX register value for BIOS call
704 * @eax: EAX register on return from the BIOS call
707 * Make a BIOS call that returns one value only, or just status.
708 * If there is an error, then the error code is returned in @err
709 * and this function returns non-zero. This is used for simpler
710 * BIOS operations. This call may hold interrupts off for a long
711 * time on some laptops.
713 static int apm_bios_call_simple(u32 func
, u32 ebx_in
, u32 ecx_in
, u32
*eax
,
716 struct apm_bios_call call
;
723 ret
= on_cpu0(__apm_bios_call_simple
, &call
);
730 * apm_driver_version - APM driver version
731 * @val: loaded with the APM version on return
733 * Retrieve the APM version supported by the BIOS. This is only
734 * supported for APM 1.1 or higher. An error indicates APM 1.0 is
737 * On entry val should point to a value indicating the APM driver
738 * version with the high byte being the major and the low byte the
739 * minor number both in BCD
741 * On return it will hold the BIOS revision supported in the
745 static int apm_driver_version(u_short
*val
)
750 if (apm_bios_call_simple(APM_FUNC_VERSION
, 0, *val
, &eax
, &err
))
757 * apm_get_event - get an APM event from the BIOS
758 * @event: pointer to the event
759 * @info: point to the event information
761 * The APM BIOS provides a polled information for event
762 * reporting. The BIOS expects to be polled at least every second
763 * when events are pending. When a message is found the caller should
764 * poll until no more messages are present. However, this causes
765 * problems on some laptops where a suspend event notification is
766 * not cleared until it is acknowledged.
768 * Additional information is returned in the info pointer, providing
769 * that APM 1.2 is in use. If no messges are pending the value 0x80
770 * is returned (No power management events pending).
772 static int apm_get_event(apm_event_t
*event
, apm_eventinfo_t
*info
)
774 struct apm_bios_call call
;
776 call
.func
= APM_FUNC_GET_EVENT
;
777 call
.ebx
= call
.ecx
= 0;
779 if (apm_bios_call(&call
))
783 if (apm_info
.connection_version
< 0x0102)
784 *info
= ~0; /* indicate info not valid */
791 * set_power_state - set the power management state
792 * @what: which items to transition
793 * @state: state to transition to
795 * Request an APM change of state for one or more system devices. The
796 * processor state must be transitioned last of all. what holds the
797 * class of device in the upper byte and the device number (0xFF for
798 * all) for the object to be transitioned.
800 * The state holds the state to transition to, which may in fact
801 * be an acceptance of a BIOS requested state change.
804 static int set_power_state(u_short what
, u_short state
)
809 if (apm_bios_call_simple(APM_FUNC_SET_STATE
, what
, state
, &eax
, &err
))
815 * set_system_power_state - set system wide power state
816 * @state: which state to enter
818 * Transition the entire system into a new APM power state.
821 static int set_system_power_state(u_short state
)
823 return set_power_state(APM_DEVICE_ALL
, state
);
827 * apm_do_idle - perform power saving
829 * This function notifies the BIOS that the processor is (in the view
830 * of the OS) idle. It returns -1 in the event that the BIOS refuses
831 * to handle the idle request. On a success the function returns 1
832 * if the BIOS did clock slowing or 0 otherwise.
835 static int apm_do_idle(void)
842 if (!need_resched()) {
844 ret
= apm_bios_call_simple(APM_FUNC_IDLE
, 0, 0, &eax
, &err
);
851 static unsigned long t
;
853 /* This always fails on some SMP boards running UP kernels.
854 * Only report the failure the first 5 times.
857 printk(KERN_DEBUG
"apm_do_idle failed (%d)\n", err
);
862 clock_slowed
= (apm_info
.bios
.flags
& APM_IDLE_SLOWS_CLOCK
) != 0;
867 * apm_do_busy - inform the BIOS the CPU is busy
869 * Request that the BIOS brings the CPU back to full performance.
872 static void apm_do_busy(void)
877 if (clock_slowed
|| ALWAYS_CALL_BUSY
) {
878 (void)apm_bios_call_simple(APM_FUNC_BUSY
, 0, 0, &dummy
, &err
);
884 * If no process has really been interested in
885 * the CPU for some time, we want to call BIOS
886 * power management - we probably want
889 #define IDLE_CALC_LIMIT (HZ * 100)
890 #define IDLE_LEAKY_MAX 16
893 * apm_cpu_idle - cpu idling for APM capable Linux
895 * This is the idling function the kernel executes when APM is available. It
896 * tries to do BIOS powermanagement based on the average system idle time.
897 * Furthermore it calls the system default idle routine.
900 static int apm_cpu_idle(struct cpuidle_device
*dev
,
901 struct cpuidle_driver
*drv
, int index
)
903 static int use_apm_idle
; /* = 0 */
904 static unsigned int last_jiffies
; /* = 0 */
905 static u64 last_stime
; /* = 0 */
908 int apm_idle_done
= 0;
909 unsigned int jiffies_since_last_check
= jiffies
- last_jiffies
;
913 task_cputime(current
, &utime
, &stime
);
914 if (jiffies_since_last_check
> IDLE_CALC_LIMIT
) {
916 } else if (jiffies_since_last_check
> idle_period
) {
917 unsigned int idle_percentage
;
919 idle_percentage
= nsecs_to_jiffies(stime
- last_stime
);
920 idle_percentage
*= 100;
921 idle_percentage
/= jiffies_since_last_check
;
922 use_apm_idle
= (idle_percentage
> idle_threshold
);
923 if (apm_info
.forbid_idle
)
927 last_jiffies
= jiffies
;
930 bucket
= IDLE_LEAKY_MAX
;
932 while (!need_resched()) {
937 switch (apm_do_idle()) {
942 bucket
= IDLE_LEAKY_MAX
;
953 default: /* BIOS refused */
959 jiffies_since_last_check
= jiffies
- last_jiffies
;
960 if (jiffies_since_last_check
> idle_period
)
971 * apm_power_off - ask the BIOS to power off
973 * Handle the power off sequence. This is the one piece of code we
974 * will execute even on SMP machines. In order to deal with BIOS
975 * bugs we support real mode APM BIOS power off calls. We also make
976 * the SMP call on CPU0 as some systems will only honour this call
977 * on their first cpu.
980 static void apm_power_off(void)
982 /* Some bioses don't like being called from CPU != 0 */
983 if (apm_info
.realmode_power_off
) {
984 set_cpus_allowed_ptr(current
, cpumask_of(0));
985 machine_real_restart(MRR_APM
);
987 (void)set_system_power_state(APM_STATE_OFF
);
991 #ifdef CONFIG_APM_DO_ENABLE
994 * apm_enable_power_management - enable BIOS APM power management
995 * @enable: enable yes/no
997 * Enable or disable the APM BIOS power services.
1000 static int apm_enable_power_management(int enable
)
1005 if ((enable
== 0) && (apm_info
.bios
.flags
& APM_BIOS_DISENGAGED
))
1006 return APM_NOT_ENGAGED
;
1007 if (apm_bios_call_simple(APM_FUNC_ENABLE_PM
, APM_DEVICE_BALL
,
1008 enable
, &eax
, &err
))
1011 apm_info
.bios
.flags
&= ~APM_BIOS_DISABLED
;
1013 apm_info
.bios
.flags
|= APM_BIOS_DISABLED
;
1019 * apm_get_power_status - get current power state
1020 * @status: returned status
1021 * @bat: battery info
1022 * @life: estimated life
1024 * Obtain the current power status from the APM BIOS. We return a
1025 * status which gives the rough battery status, and current power
1026 * source. The bat value returned give an estimate as a percentage
1027 * of life and a status value for the battery. The estimated life
1028 * if reported is a lifetime in secodnds/minutes at current powwer
1032 static int apm_get_power_status(u_short
*status
, u_short
*bat
, u_short
*life
)
1034 struct apm_bios_call call
;
1036 call
.func
= APM_FUNC_GET_STATUS
;
1037 call
.ebx
= APM_DEVICE_ALL
;
1040 if (apm_info
.get_power_status_broken
)
1041 return APM_32_UNSUPPORTED
;
1042 if (apm_bios_call(&call
)) {
1044 return APM_NO_ERROR
;
1049 if (apm_info
.get_power_status_swabinminutes
) {
1050 *life
= swab16((u16
)call
.edx
);
1058 static int apm_get_battery_status(u_short which
, u_short
*status
,
1059 u_short
*bat
, u_short
*life
, u_short
*nbat
)
1067 if (apm_info
.connection_version
< 0x0102) {
1068 /* pretend we only have one battery. */
1070 return APM_BAD_DEVICE
;
1072 return apm_get_power_status(status
, bat
, life
);
1075 if (apm_bios_call(APM_FUNC_GET_STATUS
, (0x8000 | (which
)), 0, &eax
,
1076 &ebx
, &ecx
, &edx
, &esi
))
1077 return (eax
>> 8) & 0xff;
1087 * apm_engage_power_management - enable PM on a device
1088 * @device: identity of device
1091 * Activate or deactivate power management on either a specific device
1092 * or the entire system (%APM_DEVICE_ALL).
1095 static int apm_engage_power_management(u_short device
, int enable
)
1100 if ((enable
== 0) && (device
== APM_DEVICE_ALL
)
1101 && (apm_info
.bios
.flags
& APM_BIOS_DISABLED
))
1102 return APM_DISABLED
;
1103 if (apm_bios_call_simple(APM_FUNC_ENGAGE_PM
, device
, enable
,
1106 if (device
== APM_DEVICE_ALL
) {
1108 apm_info
.bios
.flags
&= ~APM_BIOS_DISENGAGED
;
1110 apm_info
.bios
.flags
|= APM_BIOS_DISENGAGED
;
1115 #if defined(CONFIG_APM_DISPLAY_BLANK) && defined(CONFIG_VT)
1118 * apm_console_blank - blank the display
1121 * Attempt to blank the console, firstly by blanking just video device
1122 * zero, and if that fails (some BIOSes don't support it) then it blanks
1123 * all video devices. Typically the BIOS will do laptop backlight and
1124 * monitor powerdown for us.
1127 static int apm_console_blank(int blank
)
1129 int error
= APM_NOT_ENGAGED
; /* silence gcc */
1132 static const u_short dev
[3] = { 0x100, 0x1FF, 0x101 };
1134 state
= blank
? APM_STATE_STANDBY
: APM_STATE_READY
;
1136 for (i
= 0; i
< ARRAY_SIZE(dev
); i
++) {
1137 error
= set_power_state(dev
[i
], state
);
1139 if ((error
== APM_SUCCESS
) || (error
== APM_NO_ERROR
))
1142 if (error
== APM_NOT_ENGAGED
)
1146 if (error
== APM_NOT_ENGAGED
) {
1150 eng_error
= apm_engage_power_management(APM_DEVICE_ALL
, 1);
1152 apm_error("set display", error
);
1153 apm_error("engage interface", eng_error
);
1156 return apm_console_blank(blank
);
1159 apm_error("set display", error
);
1164 static int queue_empty(struct apm_user
*as
)
1166 return as
->event_head
== as
->event_tail
;
1169 static apm_event_t
get_queued_event(struct apm_user
*as
)
1171 if (++as
->event_tail
>= APM_MAX_EVENTS
)
1173 return as
->events
[as
->event_tail
];
1176 static void queue_event(apm_event_t event
, struct apm_user
*sender
)
1178 struct apm_user
*as
;
1180 spin_lock(&user_list_lock
);
1181 if (user_list
== NULL
)
1183 for (as
= user_list
; as
!= NULL
; as
= as
->next
) {
1184 if ((as
== sender
) || (!as
->reader
))
1186 if (++as
->event_head
>= APM_MAX_EVENTS
)
1189 if (as
->event_head
== as
->event_tail
) {
1190 static int notified
;
1192 if (notified
++ == 0)
1193 pr_err("an event queue overflowed\n");
1194 if (++as
->event_tail
>= APM_MAX_EVENTS
)
1197 as
->events
[as
->event_head
] = event
;
1198 if (!as
->suser
|| !as
->writer
)
1201 case APM_SYS_SUSPEND
:
1202 case APM_USER_SUSPEND
:
1203 as
->suspends_pending
++;
1207 case APM_SYS_STANDBY
:
1208 case APM_USER_STANDBY
:
1209 as
->standbys_pending
++;
1214 wake_up_interruptible(&apm_waitqueue
);
1216 spin_unlock(&user_list_lock
);
1219 static void reinit_timer(void)
1221 #ifdef INIT_TIMER_AFTER_SUSPEND
1222 unsigned long flags
;
1224 raw_spin_lock_irqsave(&i8253_lock
, flags
);
1225 /* set the clock to HZ */
1226 outb_p(0x34, PIT_MODE
); /* binary, mode 2, LSB/MSB, ch 0 */
1228 outb_p(LATCH
& 0xff, PIT_CH0
); /* LSB */
1230 outb_p(LATCH
>> 8, PIT_CH0
); /* MSB */
1232 raw_spin_unlock_irqrestore(&i8253_lock
, flags
);
1236 static int suspend(int vetoable
)
1239 struct apm_user
*as
;
1241 dpm_suspend_start(PMSG_SUSPEND
);
1242 dpm_suspend_end(PMSG_SUSPEND
);
1244 local_irq_disable();
1249 save_processor_state();
1250 err
= set_system_power_state(APM_STATE_SUSPEND
);
1251 ignore_normal_resume
= 1;
1252 restore_processor_state();
1254 local_irq_disable();
1257 if (err
== APM_NO_ERROR
)
1259 if (err
!= APM_SUCCESS
)
1260 apm_error("suspend", err
);
1261 err
= (err
== APM_SUCCESS
) ? 0 : -EIO
;
1266 dpm_resume_start(PMSG_RESUME
);
1267 dpm_resume_end(PMSG_RESUME
);
1269 queue_event(APM_NORMAL_RESUME
, NULL
);
1270 spin_lock(&user_list_lock
);
1271 for (as
= user_list
; as
!= NULL
; as
= as
->next
) {
1272 as
->suspend_wait
= 0;
1273 as
->suspend_result
= err
;
1275 spin_unlock(&user_list_lock
);
1276 wake_up_interruptible(&apm_suspend_waitqueue
);
1280 static void standby(void)
1284 dpm_suspend_end(PMSG_SUSPEND
);
1286 local_irq_disable();
1290 err
= set_system_power_state(APM_STATE_STANDBY
);
1291 if ((err
!= APM_SUCCESS
) && (err
!= APM_NO_ERROR
))
1292 apm_error("standby", err
);
1294 local_irq_disable();
1298 dpm_resume_start(PMSG_RESUME
);
1301 static apm_event_t
get_event(void)
1304 apm_event_t event
= APM_NO_EVENTS
; /* silence gcc */
1305 apm_eventinfo_t info
;
1307 static int notified
;
1309 /* we don't use the eventinfo */
1310 error
= apm_get_event(&event
, &info
);
1311 if (error
== APM_SUCCESS
)
1314 if ((error
!= APM_NO_EVENTS
) && (notified
++ == 0))
1315 apm_error("get_event", error
);
1320 static void check_events(void)
1323 static unsigned long last_resume
;
1324 static int ignore_bounce
;
1326 while ((event
= get_event()) != 0) {
1328 if (event
<= NR_APM_EVENT_NAME
)
1329 printk(KERN_DEBUG
"apm: received %s notify\n",
1330 apm_event_name
[event
- 1]);
1332 printk(KERN_DEBUG
"apm: received unknown "
1333 "event 0x%02x\n", event
);
1336 && (time_after(jiffies
, last_resume
+ bounce_interval
)))
1340 case APM_SYS_STANDBY
:
1341 case APM_USER_STANDBY
:
1342 queue_event(event
, NULL
);
1343 if (standbys_pending
<= 0)
1347 case APM_USER_SUSPEND
:
1348 #ifdef CONFIG_APM_IGNORE_USER_SUSPEND
1349 if (apm_info
.connection_version
> 0x100)
1350 set_system_power_state(APM_STATE_REJECT
);
1353 case APM_SYS_SUSPEND
:
1354 if (ignore_bounce
) {
1355 if (apm_info
.connection_version
> 0x100)
1356 set_system_power_state(APM_STATE_REJECT
);
1360 * If we are already processing a SUSPEND,
1361 * then further SUSPEND events from the BIOS
1362 * will be ignored. We also return here to
1363 * cope with the fact that the Thinkpads keep
1364 * sending a SUSPEND event until something else
1367 if (ignore_sys_suspend
)
1369 ignore_sys_suspend
= 1;
1370 queue_event(event
, NULL
);
1371 if (suspends_pending
<= 0)
1375 case APM_NORMAL_RESUME
:
1376 case APM_CRITICAL_RESUME
:
1377 case APM_STANDBY_RESUME
:
1378 ignore_sys_suspend
= 0;
1379 last_resume
= jiffies
;
1381 if ((event
!= APM_NORMAL_RESUME
)
1382 || (ignore_normal_resume
== 0)) {
1383 dpm_resume_end(PMSG_RESUME
);
1384 queue_event(event
, NULL
);
1386 ignore_normal_resume
= 0;
1389 case APM_CAPABILITY_CHANGE
:
1390 case APM_LOW_BATTERY
:
1391 case APM_POWER_STATUS_CHANGE
:
1392 queue_event(event
, NULL
);
1393 /* If needed, notify drivers here */
1396 case APM_UPDATE_TIME
:
1399 case APM_CRITICAL_SUSPEND
:
1401 * We are not allowed to reject a critical suspend.
1409 static void apm_event_handler(void)
1411 static int pending_count
= 4;
1414 if ((standbys_pending
> 0) || (suspends_pending
> 0)) {
1415 if ((apm_info
.connection_version
> 0x100) &&
1416 (pending_count
-- <= 0)) {
1419 printk(KERN_DEBUG
"apm: setting state busy\n");
1420 err
= set_system_power_state(APM_STATE_BUSY
);
1422 apm_error("busy", err
);
1430 * This is the APM thread main loop.
1433 static void apm_mainloop(void)
1435 DECLARE_WAITQUEUE(wait
, current
);
1437 add_wait_queue(&apm_waitqueue
, &wait
);
1438 set_current_state(TASK_INTERRUPTIBLE
);
1440 schedule_timeout(APM_CHECK_TIMEOUT
);
1441 if (kthread_should_stop())
1444 * Ok, check all events, check for idle (and mark us sleeping
1445 * so as not to count towards the load average)..
1447 set_current_state(TASK_INTERRUPTIBLE
);
1448 apm_event_handler();
1450 remove_wait_queue(&apm_waitqueue
, &wait
);
1453 static int check_apm_user(struct apm_user
*as
, const char *func
)
1455 if (as
== NULL
|| as
->magic
!= APM_BIOS_MAGIC
) {
1456 pr_err("%s passed bad filp\n", func
);
1462 static ssize_t
do_read(struct file
*fp
, char __user
*buf
, size_t count
, loff_t
*ppos
)
1464 struct apm_user
*as
;
1468 as
= fp
->private_data
;
1469 if (check_apm_user(as
, "read"))
1471 if ((int)count
< sizeof(apm_event_t
))
1473 if ((queue_empty(as
)) && (fp
->f_flags
& O_NONBLOCK
))
1475 wait_event_interruptible(apm_waitqueue
, !queue_empty(as
));
1477 while ((i
>= sizeof(event
)) && !queue_empty(as
)) {
1478 event
= get_queued_event(as
);
1479 if (copy_to_user(buf
, &event
, sizeof(event
))) {
1485 case APM_SYS_SUSPEND
:
1486 case APM_USER_SUSPEND
:
1487 as
->suspends_read
++;
1490 case APM_SYS_STANDBY
:
1491 case APM_USER_STANDBY
:
1492 as
->standbys_read
++;
1495 buf
+= sizeof(event
);
1500 if (signal_pending(current
))
1501 return -ERESTARTSYS
;
1505 static __poll_t
do_poll(struct file
*fp
, poll_table
*wait
)
1507 struct apm_user
*as
;
1509 as
= fp
->private_data
;
1510 if (check_apm_user(as
, "poll"))
1512 poll_wait(fp
, &apm_waitqueue
, wait
);
1513 if (!queue_empty(as
))
1514 return EPOLLIN
| EPOLLRDNORM
;
1518 static long do_ioctl(struct file
*filp
, u_int cmd
, u_long arg
)
1520 struct apm_user
*as
;
1523 as
= filp
->private_data
;
1524 if (check_apm_user(as
, "ioctl"))
1526 if (!as
->suser
|| !as
->writer
)
1529 case APM_IOC_STANDBY
:
1530 mutex_lock(&apm_mutex
);
1531 if (as
->standbys_read
> 0) {
1532 as
->standbys_read
--;
1533 as
->standbys_pending
--;
1536 queue_event(APM_USER_STANDBY
, as
);
1537 if (standbys_pending
<= 0)
1539 mutex_unlock(&apm_mutex
);
1541 case APM_IOC_SUSPEND
:
1542 mutex_lock(&apm_mutex
);
1543 if (as
->suspends_read
> 0) {
1544 as
->suspends_read
--;
1545 as
->suspends_pending
--;
1548 queue_event(APM_USER_SUSPEND
, as
);
1549 if (suspends_pending
<= 0) {
1551 mutex_unlock(&apm_mutex
);
1553 as
->suspend_wait
= 1;
1554 mutex_unlock(&apm_mutex
);
1555 wait_event_interruptible(apm_suspend_waitqueue
,
1556 as
->suspend_wait
== 0);
1557 ret
= as
->suspend_result
;
1566 static int do_release(struct inode
*inode
, struct file
*filp
)
1568 struct apm_user
*as
;
1570 as
= filp
->private_data
;
1571 if (check_apm_user(as
, "release"))
1573 filp
->private_data
= NULL
;
1574 if (as
->standbys_pending
> 0) {
1575 standbys_pending
-= as
->standbys_pending
;
1576 if (standbys_pending
<= 0)
1579 if (as
->suspends_pending
> 0) {
1580 suspends_pending
-= as
->suspends_pending
;
1581 if (suspends_pending
<= 0)
1584 spin_lock(&user_list_lock
);
1585 if (user_list
== as
)
1586 user_list
= as
->next
;
1588 struct apm_user
*as1
;
1590 for (as1
= user_list
;
1591 (as1
!= NULL
) && (as1
->next
!= as
);
1595 pr_err("filp not in user list\n");
1597 as1
->next
= as
->next
;
1599 spin_unlock(&user_list_lock
);
1604 static int do_open(struct inode
*inode
, struct file
*filp
)
1606 struct apm_user
*as
;
1608 as
= kmalloc(sizeof(*as
), GFP_KERNEL
);
1612 as
->magic
= APM_BIOS_MAGIC
;
1613 as
->event_tail
= as
->event_head
= 0;
1614 as
->suspends_pending
= as
->standbys_pending
= 0;
1615 as
->suspends_read
= as
->standbys_read
= 0;
1617 * XXX - this is a tiny bit broken, when we consider BSD
1618 * process accounting. If the device is opened by root, we
1619 * instantly flag that we used superuser privs. Who knows,
1620 * we might close the device immediately without doing a
1621 * privileged operation -- cevans
1623 as
->suser
= capable(CAP_SYS_ADMIN
);
1624 as
->writer
= (filp
->f_mode
& FMODE_WRITE
) == FMODE_WRITE
;
1625 as
->reader
= (filp
->f_mode
& FMODE_READ
) == FMODE_READ
;
1626 spin_lock(&user_list_lock
);
1627 as
->next
= user_list
;
1629 spin_unlock(&user_list_lock
);
1630 filp
->private_data
= as
;
1634 #ifdef CONFIG_PROC_FS
1635 static int proc_apm_show(struct seq_file
*m
, void *v
)
1641 unsigned short ac_line_status
= 0xff;
1642 unsigned short battery_status
= 0xff;
1643 unsigned short battery_flag
= 0xff;
1644 int percentage
= -1;
1645 int time_units
= -1;
1648 if ((num_online_cpus() == 1) &&
1649 !(error
= apm_get_power_status(&bx
, &cx
, &dx
))) {
1650 ac_line_status
= (bx
>> 8) & 0xff;
1651 battery_status
= bx
& 0xff;
1652 if ((cx
& 0xff) != 0xff)
1653 percentage
= cx
& 0xff;
1655 if (apm_info
.connection_version
> 0x100) {
1656 battery_flag
= (cx
>> 8) & 0xff;
1658 units
= (dx
& 0x8000) ? "min" : "sec";
1659 time_units
= dx
& 0x7fff;
1663 /* Arguments, with symbols from linux/apm_bios.h. Information is
1664 from the Get Power Status (0x0a) call unless otherwise noted.
1666 0) Linux driver version (this will change if format changes)
1667 1) APM BIOS Version. Usually 1.0, 1.1 or 1.2.
1668 2) APM flags from APM Installation Check (0x00):
1669 bit 0: APM_16_BIT_SUPPORT
1670 bit 1: APM_32_BIT_SUPPORT
1671 bit 2: APM_IDLE_SLOWS_CLOCK
1672 bit 3: APM_BIOS_DISABLED
1673 bit 4: APM_BIOS_DISENGAGED
1677 0x02: On backup power (BIOS >= 1.1 only)
1684 0x04: Selected battery not present (BIOS >= 1.2 only)
1691 bit 7: No system battery
1693 6) Remaining battery life (percentage of charge):
1696 7) Remaining battery life (time units):
1697 Number of remaining minutes or seconds
1699 8) min = minutes; sec = seconds */
1701 seq_printf(m
, "%s %d.%d 0x%02x 0x%02x 0x%02x 0x%02x %d%% %d %s\n",
1703 (apm_info
.bios
.version
>> 8) & 0xff,
1704 apm_info
.bios
.version
& 0xff,
1705 apm_info
.bios
.flags
,
1716 static int apm(void *unused
)
1726 * This is to avoid random crashes at boot time during initialization
1727 * on SMP systems in case of "apm=power-off" mode. Seen on ASUS A7M266D.
1728 * Some bioses don't like being called from CPU != 0.
1729 * Method suggested by Ingo Molnar.
1731 set_cpus_allowed_ptr(current
, cpumask_of(0));
1732 BUG_ON(smp_processor_id() != 0);
1734 if (apm_info
.connection_version
== 0) {
1735 apm_info
.connection_version
= apm_info
.bios
.version
;
1736 if (apm_info
.connection_version
> 0x100) {
1738 * We only support BIOSs up to version 1.2
1740 if (apm_info
.connection_version
> 0x0102)
1741 apm_info
.connection_version
= 0x0102;
1742 error
= apm_driver_version(&apm_info
.connection_version
);
1743 if (error
!= APM_SUCCESS
) {
1744 apm_error("driver version", error
);
1745 /* Fall back to an APM 1.0 connection. */
1746 apm_info
.connection_version
= 0x100;
1752 printk(KERN_INFO
"apm: Connection version %d.%d\n",
1753 (apm_info
.connection_version
>> 8) & 0xff,
1754 apm_info
.connection_version
& 0xff);
1756 #ifdef CONFIG_APM_DO_ENABLE
1757 if (apm_info
.bios
.flags
& APM_BIOS_DISABLED
) {
1759 * This call causes my NEC UltraLite Versa 33/C to hang if it
1760 * is booted with PM disabled but not in the docking station.
1763 error
= apm_enable_power_management(1);
1765 apm_error("enable power management", error
);
1771 if ((apm_info
.bios
.flags
& APM_BIOS_DISENGAGED
)
1772 && (apm_info
.connection_version
> 0x0100)) {
1773 error
= apm_engage_power_management(APM_DEVICE_ALL
, 1);
1775 apm_error("engage power management", error
);
1780 if (debug
&& (num_online_cpus() == 1 || smp
)) {
1781 error
= apm_get_power_status(&bx
, &cx
, &dx
);
1783 printk(KERN_INFO
"apm: power status not available\n");
1785 switch ((bx
>> 8) & 0xff) {
1787 power_stat
= "off line";
1790 power_stat
= "on line";
1793 power_stat
= "on backup power";
1796 power_stat
= "unknown";
1799 switch (bx
& 0xff) {
1807 bat_stat
= "critical";
1810 bat_stat
= "charging";
1813 bat_stat
= "unknown";
1817 "apm: AC %s, battery status %s, battery life ",
1818 power_stat
, bat_stat
);
1819 if ((cx
& 0xff) == 0xff)
1820 printk("unknown\n");
1822 printk("%d%%\n", cx
& 0xff);
1823 if (apm_info
.connection_version
> 0x100) {
1825 "apm: battery flag 0x%02x, battery life ",
1828 printk("unknown\n");
1830 printk("%d %s\n", dx
& 0x7fff,
1832 "minutes" : "seconds");
1837 /* Install our power off handler.. */
1839 pm_power_off
= apm_power_off
;
1841 if (num_online_cpus() == 1 || smp
) {
1842 #if defined(CONFIG_APM_DISPLAY_BLANK) && defined(CONFIG_VT)
1843 console_blank_hook
= apm_console_blank
;
1846 #if defined(CONFIG_APM_DISPLAY_BLANK) && defined(CONFIG_VT)
1847 console_blank_hook
= NULL
;
1855 static int __init
apm_setup(char *str
)
1859 while ((str
!= NULL
) && (*str
!= '\0')) {
1860 if (strncmp(str
, "off", 3) == 0)
1862 if (strncmp(str
, "on", 2) == 0)
1864 if ((strncmp(str
, "bounce-interval=", 16) == 0) ||
1865 (strncmp(str
, "bounce_interval=", 16) == 0))
1866 bounce_interval
= simple_strtol(str
+ 16, NULL
, 0);
1867 if ((strncmp(str
, "idle-threshold=", 15) == 0) ||
1868 (strncmp(str
, "idle_threshold=", 15) == 0))
1869 idle_threshold
= simple_strtol(str
+ 15, NULL
, 0);
1870 if ((strncmp(str
, "idle-period=", 12) == 0) ||
1871 (strncmp(str
, "idle_period=", 12) == 0))
1872 idle_period
= simple_strtol(str
+ 12, NULL
, 0);
1873 invert
= (strncmp(str
, "no-", 3) == 0) ||
1874 (strncmp(str
, "no_", 3) == 0);
1877 if (strncmp(str
, "debug", 5) == 0)
1879 if ((strncmp(str
, "power-off", 9) == 0) ||
1880 (strncmp(str
, "power_off", 9) == 0))
1881 power_off
= !invert
;
1882 if (strncmp(str
, "smp", 3) == 0) {
1884 idle_threshold
= 100;
1886 if ((strncmp(str
, "allow-ints", 10) == 0) ||
1887 (strncmp(str
, "allow_ints", 10) == 0))
1888 apm_info
.allow_ints
= !invert
;
1889 if ((strncmp(str
, "broken-psr", 10) == 0) ||
1890 (strncmp(str
, "broken_psr", 10) == 0))
1891 apm_info
.get_power_status_broken
= !invert
;
1892 if ((strncmp(str
, "realmode-power-off", 18) == 0) ||
1893 (strncmp(str
, "realmode_power_off", 18) == 0))
1894 apm_info
.realmode_power_off
= !invert
;
1895 str
= strchr(str
, ',');
1897 str
+= strspn(str
, ", \t");
1902 __setup("apm=", apm_setup
);
1905 static const struct file_operations apm_bios_fops
= {
1906 .owner
= THIS_MODULE
,
1909 .unlocked_ioctl
= do_ioctl
,
1911 .release
= do_release
,
1912 .llseek
= noop_llseek
,
1915 static struct miscdevice apm_device
= {
1922 /* Simple "print if true" callback */
1923 static int __init
print_if_true(const struct dmi_system_id
*d
)
1925 printk("%s\n", d
->ident
);
1930 * Some Bioses enable the PS/2 mouse (touchpad) at resume, even if it was
1931 * disabled before the suspend. Linux used to get terribly confused by that.
1933 static int __init
broken_ps2_resume(const struct dmi_system_id
*d
)
1935 printk(KERN_INFO
"%s machine detected. Mousepad Resume Bug "
1936 "workaround hopefully not needed.\n", d
->ident
);
1940 /* Some bioses have a broken protected mode poweroff and need to use realmode */
1941 static int __init
set_realmode_power_off(const struct dmi_system_id
*d
)
1943 if (apm_info
.realmode_power_off
== 0) {
1944 apm_info
.realmode_power_off
= 1;
1945 printk(KERN_INFO
"%s bios detected. "
1946 "Using realmode poweroff only.\n", d
->ident
);
1951 /* Some laptops require interrupts to be enabled during APM calls */
1952 static int __init
set_apm_ints(const struct dmi_system_id
*d
)
1954 if (apm_info
.allow_ints
== 0) {
1955 apm_info
.allow_ints
= 1;
1956 printk(KERN_INFO
"%s machine detected. "
1957 "Enabling interrupts during APM calls.\n", d
->ident
);
1962 /* Some APM bioses corrupt memory or just plain do not work */
1963 static int __init
apm_is_horked(const struct dmi_system_id
*d
)
1965 if (apm_info
.disabled
== 0) {
1966 apm_info
.disabled
= 1;
1967 printk(KERN_INFO
"%s machine detected. "
1968 "Disabling APM.\n", d
->ident
);
1973 static int __init
apm_is_horked_d850md(const struct dmi_system_id
*d
)
1975 if (apm_info
.disabled
== 0) {
1976 apm_info
.disabled
= 1;
1977 printk(KERN_INFO
"%s machine detected. "
1978 "Disabling APM.\n", d
->ident
);
1979 printk(KERN_INFO
"This bug is fixed in bios P15 which is available for\n");
1980 printk(KERN_INFO
"download from support.intel.com\n");
1985 /* Some APM bioses hang on APM idle calls */
1986 static int __init
apm_likes_to_melt(const struct dmi_system_id
*d
)
1988 if (apm_info
.forbid_idle
== 0) {
1989 apm_info
.forbid_idle
= 1;
1990 printk(KERN_INFO
"%s machine detected. "
1991 "Disabling APM idle calls.\n", d
->ident
);
1997 * Check for clue free BIOS implementations who use
1998 * the following QA technique
2000 * [ Write BIOS Code ]<------
2002 * < Does it Compile >----N--
2004 * < Does it Boot Win98 >-N--
2008 * Phoenix A04 08/24/2000 is known bad (Dell Inspiron 5000e)
2009 * Phoenix A07 09/29/2000 is known good (Dell Inspiron 5000)
2011 static int __init
broken_apm_power(const struct dmi_system_id
*d
)
2013 apm_info
.get_power_status_broken
= 1;
2014 printk(KERN_WARNING
"BIOS strings suggest APM bugs, "
2015 "disabling power status reporting.\n");
2020 * This bios swaps the APM minute reporting bytes over (Many sony laptops
2021 * have this problem).
2023 static int __init
swab_apm_power_in_minutes(const struct dmi_system_id
*d
)
2025 apm_info
.get_power_status_swabinminutes
= 1;
2026 printk(KERN_WARNING
"BIOS strings suggest APM reports battery life "
2027 "in minutes and wrong byte order.\n");
2031 static const struct dmi_system_id apm_dmi_table
[] __initconst
= {
2034 KERN_WARNING
"IBM T23 - BIOS 1.03b+ and controller firmware 1.02+ may be needed for Linux APM.",
2035 { DMI_MATCH(DMI_SYS_VENDOR
, "IBM"),
2036 DMI_MATCH(DMI_BIOS_VERSION
, "1AET38WW (1.01b)"), },
2038 { /* Handle problems with APM on the C600 */
2039 broken_ps2_resume
, "Dell Latitude C600",
2040 { DMI_MATCH(DMI_SYS_VENDOR
, "Dell"),
2041 DMI_MATCH(DMI_PRODUCT_NAME
, "Latitude C600"), },
2043 { /* Allow interrupts during suspend on Dell Latitude laptops*/
2044 set_apm_ints
, "Dell Latitude",
2045 { DMI_MATCH(DMI_SYS_VENDOR
, "Dell Computer Corporation"),
2046 DMI_MATCH(DMI_PRODUCT_NAME
, "Latitude C510"), }
2049 apm_is_horked
, "Dell Inspiron 2500",
2050 { DMI_MATCH(DMI_SYS_VENDOR
, "Dell Computer Corporation"),
2051 DMI_MATCH(DMI_PRODUCT_NAME
, "Inspiron 2500"),
2052 DMI_MATCH(DMI_BIOS_VENDOR
, "Phoenix Technologies LTD"),
2053 DMI_MATCH(DMI_BIOS_VERSION
, "A11"), },
2055 { /* Allow interrupts during suspend on Dell Inspiron laptops*/
2056 set_apm_ints
, "Dell Inspiron", {
2057 DMI_MATCH(DMI_SYS_VENDOR
, "Dell Computer Corporation"),
2058 DMI_MATCH(DMI_PRODUCT_NAME
, "Inspiron 4000"), },
2060 { /* Handle problems with APM on Inspiron 5000e */
2061 broken_apm_power
, "Dell Inspiron 5000e",
2062 { DMI_MATCH(DMI_BIOS_VENDOR
, "Phoenix Technologies LTD"),
2063 DMI_MATCH(DMI_BIOS_VERSION
, "A04"),
2064 DMI_MATCH(DMI_BIOS_DATE
, "08/24/2000"), },
2066 { /* Handle problems with APM on Inspiron 2500 */
2067 broken_apm_power
, "Dell Inspiron 2500",
2068 { DMI_MATCH(DMI_BIOS_VENDOR
, "Phoenix Technologies LTD"),
2069 DMI_MATCH(DMI_BIOS_VERSION
, "A12"),
2070 DMI_MATCH(DMI_BIOS_DATE
, "02/04/2002"), },
2073 apm_is_horked
, "Dell Dimension 4100",
2074 { DMI_MATCH(DMI_SYS_VENDOR
, "Dell Computer Corporation"),
2075 DMI_MATCH(DMI_PRODUCT_NAME
, "XPS-Z"),
2076 DMI_MATCH(DMI_BIOS_VENDOR
, "Intel Corp."),
2077 DMI_MATCH(DMI_BIOS_VERSION
, "A11"), },
2079 { /* Allow interrupts during suspend on Compaq Laptops*/
2080 set_apm_ints
, "Compaq 12XL125",
2081 { DMI_MATCH(DMI_SYS_VENDOR
, "Compaq"),
2082 DMI_MATCH(DMI_PRODUCT_NAME
, "Compaq PC"),
2083 DMI_MATCH(DMI_BIOS_VENDOR
, "Phoenix Technologies LTD"),
2084 DMI_MATCH(DMI_BIOS_VERSION
, "4.06"), },
2086 { /* Allow interrupts during APM or the clock goes slow */
2087 set_apm_ints
, "ASUSTeK",
2088 { DMI_MATCH(DMI_SYS_VENDOR
, "ASUSTeK Computer Inc."),
2089 DMI_MATCH(DMI_PRODUCT_NAME
, "L8400K series Notebook PC"), },
2091 { /* APM blows on shutdown */
2092 apm_is_horked
, "ABIT KX7-333[R]",
2093 { DMI_MATCH(DMI_BOARD_VENDOR
, "ABIT"),
2094 DMI_MATCH(DMI_BOARD_NAME
, "VT8367-8233A (KX7-333[R])"), },
2097 apm_is_horked
, "Trigem Delhi3",
2098 { DMI_MATCH(DMI_SYS_VENDOR
, "TriGem Computer, Inc"),
2099 DMI_MATCH(DMI_PRODUCT_NAME
, "Delhi3"), },
2102 apm_is_horked
, "Fujitsu-Siemens",
2103 { DMI_MATCH(DMI_BIOS_VENDOR
, "hoenix/FUJITSU SIEMENS"),
2104 DMI_MATCH(DMI_BIOS_VERSION
, "Version1.01"), },
2107 apm_is_horked_d850md
, "Intel D850MD",
2108 { DMI_MATCH(DMI_BIOS_VENDOR
, "Intel Corp."),
2109 DMI_MATCH(DMI_BIOS_VERSION
, "MV85010A.86A.0016.P07.0201251536"), },
2112 apm_is_horked
, "Intel D810EMO",
2113 { DMI_MATCH(DMI_BIOS_VENDOR
, "Intel Corp."),
2114 DMI_MATCH(DMI_BIOS_VERSION
, "MO81010A.86A.0008.P04.0004170800"), },
2117 apm_is_horked
, "Dell XPS-Z",
2118 { DMI_MATCH(DMI_BIOS_VENDOR
, "Intel Corp."),
2119 DMI_MATCH(DMI_BIOS_VERSION
, "A11"),
2120 DMI_MATCH(DMI_PRODUCT_NAME
, "XPS-Z"), },
2123 apm_is_horked
, "Sharp PC-PJ/AX",
2124 { DMI_MATCH(DMI_SYS_VENDOR
, "SHARP"),
2125 DMI_MATCH(DMI_PRODUCT_NAME
, "PC-PJ/AX"),
2126 DMI_MATCH(DMI_BIOS_VENDOR
, "SystemSoft"),
2127 DMI_MATCH(DMI_BIOS_VERSION
, "Version R2.08"), },
2130 apm_is_horked
, "Dell Inspiron 2500",
2131 { DMI_MATCH(DMI_SYS_VENDOR
, "Dell Computer Corporation"),
2132 DMI_MATCH(DMI_PRODUCT_NAME
, "Inspiron 2500"),
2133 DMI_MATCH(DMI_BIOS_VENDOR
, "Phoenix Technologies LTD"),
2134 DMI_MATCH(DMI_BIOS_VERSION
, "A11"), },
2136 { /* APM idle hangs */
2137 apm_likes_to_melt
, "Jabil AMD",
2138 { DMI_MATCH(DMI_BIOS_VENDOR
, "American Megatrends Inc."),
2139 DMI_MATCH(DMI_BIOS_VERSION
, "0AASNP06"), },
2141 { /* APM idle hangs */
2142 apm_likes_to_melt
, "AMI Bios",
2143 { DMI_MATCH(DMI_BIOS_VENDOR
, "American Megatrends Inc."),
2144 DMI_MATCH(DMI_BIOS_VERSION
, "0AASNP05"), },
2146 { /* Handle problems with APM on Sony Vaio PCG-N505X(DE) */
2147 swab_apm_power_in_minutes
, "Sony VAIO",
2148 { DMI_MATCH(DMI_BIOS_VENDOR
, "Phoenix Technologies LTD"),
2149 DMI_MATCH(DMI_BIOS_VERSION
, "R0206H"),
2150 DMI_MATCH(DMI_BIOS_DATE
, "08/23/99"), },
2152 { /* Handle problems with APM on Sony Vaio PCG-N505VX */
2153 swab_apm_power_in_minutes
, "Sony VAIO",
2154 { DMI_MATCH(DMI_BIOS_VENDOR
, "Phoenix Technologies LTD"),
2155 DMI_MATCH(DMI_BIOS_VERSION
, "W2K06H0"),
2156 DMI_MATCH(DMI_BIOS_DATE
, "02/03/00"), },
2158 { /* Handle problems with APM on Sony Vaio PCG-XG29 */
2159 swab_apm_power_in_minutes
, "Sony VAIO",
2160 { DMI_MATCH(DMI_BIOS_VENDOR
, "Phoenix Technologies LTD"),
2161 DMI_MATCH(DMI_BIOS_VERSION
, "R0117A0"),
2162 DMI_MATCH(DMI_BIOS_DATE
, "04/25/00"), },
2164 { /* Handle problems with APM on Sony Vaio PCG-Z600NE */
2165 swab_apm_power_in_minutes
, "Sony VAIO",
2166 { DMI_MATCH(DMI_BIOS_VENDOR
, "Phoenix Technologies LTD"),
2167 DMI_MATCH(DMI_BIOS_VERSION
, "R0121Z1"),
2168 DMI_MATCH(DMI_BIOS_DATE
, "05/11/00"), },
2170 { /* Handle problems with APM on Sony Vaio PCG-Z600NE */
2171 swab_apm_power_in_minutes
, "Sony VAIO",
2172 { DMI_MATCH(DMI_BIOS_VENDOR
, "Phoenix Technologies LTD"),
2173 DMI_MATCH(DMI_BIOS_VERSION
, "WME01Z1"),
2174 DMI_MATCH(DMI_BIOS_DATE
, "08/11/00"), },
2176 { /* Handle problems with APM on Sony Vaio PCG-Z600LEK(DE) */
2177 swab_apm_power_in_minutes
, "Sony VAIO",
2178 { DMI_MATCH(DMI_BIOS_VENDOR
, "Phoenix Technologies LTD"),
2179 DMI_MATCH(DMI_BIOS_VERSION
, "R0206Z3"),
2180 DMI_MATCH(DMI_BIOS_DATE
, "12/25/00"), },
2182 { /* Handle problems with APM on Sony Vaio PCG-Z505LS */
2183 swab_apm_power_in_minutes
, "Sony VAIO",
2184 { DMI_MATCH(DMI_BIOS_VENDOR
, "Phoenix Technologies LTD"),
2185 DMI_MATCH(DMI_BIOS_VERSION
, "R0203D0"),
2186 DMI_MATCH(DMI_BIOS_DATE
, "05/12/00"), },
2188 { /* Handle problems with APM on Sony Vaio PCG-Z505LS */
2189 swab_apm_power_in_minutes
, "Sony VAIO",
2190 { DMI_MATCH(DMI_BIOS_VENDOR
, "Phoenix Technologies LTD"),
2191 DMI_MATCH(DMI_BIOS_VERSION
, "R0203Z3"),
2192 DMI_MATCH(DMI_BIOS_DATE
, "08/25/00"), },
2194 { /* Handle problems with APM on Sony Vaio PCG-Z505LS (with updated BIOS) */
2195 swab_apm_power_in_minutes
, "Sony VAIO",
2196 { DMI_MATCH(DMI_BIOS_VENDOR
, "Phoenix Technologies LTD"),
2197 DMI_MATCH(DMI_BIOS_VERSION
, "R0209Z3"),
2198 DMI_MATCH(DMI_BIOS_DATE
, "05/12/01"), },
2200 { /* Handle problems with APM on Sony Vaio PCG-F104K */
2201 swab_apm_power_in_minutes
, "Sony VAIO",
2202 { DMI_MATCH(DMI_BIOS_VENDOR
, "Phoenix Technologies LTD"),
2203 DMI_MATCH(DMI_BIOS_VERSION
, "R0204K2"),
2204 DMI_MATCH(DMI_BIOS_DATE
, "08/28/00"), },
2207 { /* Handle problems with APM on Sony Vaio PCG-C1VN/C1VE */
2208 swab_apm_power_in_minutes
, "Sony VAIO",
2209 { DMI_MATCH(DMI_BIOS_VENDOR
, "Phoenix Technologies LTD"),
2210 DMI_MATCH(DMI_BIOS_VERSION
, "R0208P1"),
2211 DMI_MATCH(DMI_BIOS_DATE
, "11/09/00"), },
2213 { /* Handle problems with APM on Sony Vaio PCG-C1VE */
2214 swab_apm_power_in_minutes
, "Sony VAIO",
2215 { DMI_MATCH(DMI_BIOS_VENDOR
, "Phoenix Technologies LTD"),
2216 DMI_MATCH(DMI_BIOS_VERSION
, "R0204P1"),
2217 DMI_MATCH(DMI_BIOS_DATE
, "09/12/00"), },
2219 { /* Handle problems with APM on Sony Vaio PCG-C1VE */
2220 swab_apm_power_in_minutes
, "Sony VAIO",
2221 { DMI_MATCH(DMI_BIOS_VENDOR
, "Phoenix Technologies LTD"),
2222 DMI_MATCH(DMI_BIOS_VERSION
, "WXPO1Z3"),
2223 DMI_MATCH(DMI_BIOS_DATE
, "10/26/01"), },
2225 { /* broken PM poweroff bios */
2226 set_realmode_power_off
, "Award Software v4.60 PGMA",
2227 { DMI_MATCH(DMI_BIOS_VENDOR
, "Award Software International, Inc."),
2228 DMI_MATCH(DMI_BIOS_VERSION
, "4.60 PGMA"),
2229 DMI_MATCH(DMI_BIOS_DATE
, "134526184"), },
2232 /* Generic per vendor APM settings */
2234 { /* Allow interrupts during suspend on IBM laptops */
2235 set_apm_ints
, "IBM",
2236 { DMI_MATCH(DMI_SYS_VENDOR
, "IBM"), },
2243 * Just start the APM thread. We do NOT want to do APM BIOS
2244 * calls from anything but the APM thread, if for no other reason
2245 * than the fact that we don't trust the APM BIOS. This way,
2246 * most common APM BIOS problems that lead to protection errors
2247 * etc will have at least some level of being contained...
2249 * In short, if something bad happens, at least we have a choice
2250 * of just killing the apm thread..
2252 static int __init
apm_init(void)
2254 struct desc_struct
*gdt
;
2257 dmi_check_system(apm_dmi_table
);
2259 if (apm_info
.bios
.version
== 0 || machine_is_olpc()) {
2260 printk(KERN_INFO
"apm: BIOS not found.\n");
2264 "apm: BIOS version %d.%d Flags 0x%02x (Driver version %s)\n",
2265 ((apm_info
.bios
.version
>> 8) & 0xff),
2266 (apm_info
.bios
.version
& 0xff),
2267 apm_info
.bios
.flags
,
2269 if ((apm_info
.bios
.flags
& APM_32_BIT_SUPPORT
) == 0) {
2270 printk(KERN_INFO
"apm: no 32 bit BIOS support\n");
2275 apm_info
.allow_ints
= 1;
2277 apm_info
.get_power_status_broken
= 1;
2278 if (realmode_power_off
)
2279 apm_info
.realmode_power_off
= 1;
2280 /* User can override, but default is to trust DMI */
2281 if (apm_disabled
!= -1)
2282 apm_info
.disabled
= apm_disabled
;
2285 * Fix for the Compaq Contura 3/25c which reports BIOS version 0.1
2286 * but is reportedly a 1.0 BIOS.
2288 if (apm_info
.bios
.version
== 0x001)
2289 apm_info
.bios
.version
= 0x100;
2291 /* BIOS < 1.2 doesn't set cseg_16_len */
2292 if (apm_info
.bios
.version
< 0x102)
2293 apm_info
.bios
.cseg_16_len
= 0; /* 64k */
2296 printk(KERN_INFO
"apm: entry %x:%x cseg16 %x dseg %x",
2297 apm_info
.bios
.cseg
, apm_info
.bios
.offset
,
2298 apm_info
.bios
.cseg_16
, apm_info
.bios
.dseg
);
2299 if (apm_info
.bios
.version
> 0x100)
2300 printk(" cseg len %x, dseg len %x",
2301 apm_info
.bios
.cseg_len
,
2302 apm_info
.bios
.dseg_len
);
2303 if (apm_info
.bios
.version
> 0x101)
2304 printk(" cseg16 len %x", apm_info
.bios
.cseg_16_len
);
2308 if (apm_info
.disabled
) {
2309 pr_notice("disabled on user request.\n");
2312 if ((num_online_cpus() > 1) && !power_off
&& !smp
) {
2313 pr_notice("disabled - APM is not SMP safe.\n");
2314 apm_info
.disabled
= 1;
2317 if (!acpi_disabled
) {
2318 pr_notice("overridden by ACPI.\n");
2319 apm_info
.disabled
= 1;
2324 * Set up the long jump entry point to the APM BIOS, which is called
2325 * from inline assembly.
2327 apm_bios_entry
.offset
= apm_info
.bios
.offset
;
2328 apm_bios_entry
.segment
= APM_CS
;
2331 * The APM 1.1 BIOS is supposed to provide limit information that it
2332 * recognizes. Many machines do this correctly, but many others do
2333 * not restrict themselves to their claimed limit. When this happens,
2334 * they will cause a segmentation violation in the kernel at boot time.
2335 * Most BIOS's, however, will respect a 64k limit, so we use that.
2337 * Note we only set APM segments on CPU zero, since we pin the APM
2340 gdt
= get_cpu_gdt_rw(0);
2341 set_desc_base(&gdt
[APM_CS
>> 3],
2342 (unsigned long)__va((unsigned long)apm_info
.bios
.cseg
<< 4));
2343 set_desc_base(&gdt
[APM_CS_16
>> 3],
2344 (unsigned long)__va((unsigned long)apm_info
.bios
.cseg_16
<< 4));
2345 set_desc_base(&gdt
[APM_DS
>> 3],
2346 (unsigned long)__va((unsigned long)apm_info
.bios
.dseg
<< 4));
2348 proc_create_single("apm", 0, NULL
, proc_apm_show
);
2350 kapmd_task
= kthread_create(apm
, NULL
, "kapmd");
2351 if (IS_ERR(kapmd_task
)) {
2352 pr_err("disabled - Unable to start kernel thread\n");
2353 err
= PTR_ERR(kapmd_task
);
2355 remove_proc_entry("apm", NULL
);
2358 wake_up_process(kapmd_task
);
2360 if (num_online_cpus() > 1 && !smp
) {
2362 "apm: disabled - APM is not SMP safe (power off active).\n");
2367 * Note we don't actually care if the misc_device cannot be registered.
2368 * this driver can do its job without it, even if userspace can't
2369 * control it. just log the error
2371 if (misc_register(&apm_device
))
2372 printk(KERN_WARNING
"apm: Could not register misc device.\n");
2375 idle_period
= (idle_period
* HZ
) / 100;
2376 if (idle_threshold
< 100) {
2377 cpuidle_poll_state_init(&apm_idle_driver
);
2378 if (!cpuidle_register_driver(&apm_idle_driver
))
2379 if (cpuidle_register_device(&apm_cpuidle_device
))
2380 cpuidle_unregister_driver(&apm_idle_driver
);
2386 static void __exit
apm_exit(void)
2390 cpuidle_unregister_device(&apm_cpuidle_device
);
2391 cpuidle_unregister_driver(&apm_idle_driver
);
2393 if (((apm_info
.bios
.flags
& APM_BIOS_DISENGAGED
) == 0)
2394 && (apm_info
.connection_version
> 0x0100)) {
2395 error
= apm_engage_power_management(APM_DEVICE_ALL
, 0);
2397 apm_error("disengage power management", error
);
2399 misc_deregister(&apm_device
);
2400 remove_proc_entry("apm", NULL
);
2402 pm_power_off
= NULL
;
2404 kthread_stop(kapmd_task
);
2409 module_init(apm_init
);
2410 module_exit(apm_exit
);
2412 MODULE_AUTHOR("Stephen Rothwell");
2413 MODULE_DESCRIPTION("Advanced Power Management");
2414 MODULE_LICENSE("GPL");
2415 module_param(debug
, bool, 0644);
2416 MODULE_PARM_DESC(debug
, "Enable debug mode");
2417 module_param(power_off
, bool, 0444);
2418 MODULE_PARM_DESC(power_off
, "Enable power off");
2419 module_param(bounce_interval
, int, 0444);
2420 MODULE_PARM_DESC(bounce_interval
,
2421 "Set the number of ticks to ignore suspend bounces");
2422 module_param(allow_ints
, bool, 0444);
2423 MODULE_PARM_DESC(allow_ints
, "Allow interrupts during BIOS calls");
2424 module_param(broken_psr
, bool, 0444);
2425 MODULE_PARM_DESC(broken_psr
, "BIOS has a broken GetPowerStatus call");
2426 module_param(realmode_power_off
, bool, 0444);
2427 MODULE_PARM_DESC(realmode_power_off
,
2428 "Switch to real mode before powering off");
2429 module_param(idle_threshold
, int, 0444);
2430 MODULE_PARM_DESC(idle_threshold
,
2431 "System idle percentage above which to make APM BIOS idle calls");
2432 module_param(idle_period
, int, 0444);
2433 MODULE_PARM_DESC(idle_period
,
2434 "Period (in sec/100) over which to calculate the idle percentage");
2435 module_param(smp
, bool, 0444);
2436 MODULE_PARM_DESC(smp
,
2437 "Set this to enable APM use on an SMP platform. Use with caution on older systems");
2438 MODULE_ALIAS_MISCDEV(APM_MINOR_DEV
);