x86, reboot: Move the real-mode reboot code to an assembly file
[linux-2.6.git] / arch / x86 / kernel / apm_32.c
blobb929108eb58f4ef87faea951118cdfd4bc46691c
1 /* -*- linux-c -*-
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
6 * and NEC Corporation
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
11 * later version.
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
20 * Documentation
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)
27 * Version 1.0 and 1.1
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
45 * History:
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,
51 * Linux 1.3.85
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
67 * across BIOS call).
68 * Stephen Rothwell
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>
73 * Stephen Rothwell
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
83 * Make asm safer
84 * Stephen Rothwell
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
89 * Stephen Rothwell
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.
100 * Stephen Rothwell
101 * 1.10: Fix for Thinkpad return code.
102 * Merge 2.2 and 2.3 drivers.
103 * Remove APM dependencies in arch/i386/kernel/process.c
104 * Remove APM dependencies in drivers/char/sysrq.c
105 * Reset time across standby.
106 * Allow more inititialisation on SMP.
107 * Remove CONFIG_APM_POWER_OFF and make it boot time
108 * configurable (default on).
109 * Make debug only a boot time parameter (remove APM_DEBUG).
110 * Try to blank all devices on any error.
111 * 1.11: Remove APM dependencies in drivers/char/console.c
112 * Check nr_running to detect if we are idle (from
113 * Borislav Deianov <borislav@lix.polytechnique.fr>)
114 * Fix for bioses that don't zero the top part of the
115 * entrypoint offset (Mario Sitta <sitta@al.unipmn.it>)
116 * (reported by Panos Katsaloulis <teras@writeme.com>).
117 * Real mode power off patch (Walter Hofmann
118 * <Walter.Hofmann@physik.stud.uni-erlangen.de>).
119 * 1.12: Remove CONFIG_SMP as the compiler will optimize
120 * the code away anyway (smp_num_cpus == 1 in UP)
121 * noted by Artur Skawina <skawina@geocities.com>.
122 * Make power off under SMP work again.
123 * Fix thinko with initial engaging of BIOS.
124 * Make sure power off only happens on CPU 0
125 * (Paul "Rusty" Russell <rusty@rustcorp.com.au>).
126 * Do error notification to user mode if BIOS calls fail.
127 * Move entrypoint offset fix to ...boot/setup.S
128 * where it belongs (Cosmos <gis88564@cis.nctu.edu.tw>).
129 * Remove smp-power-off. SMP users must now specify
130 * "apm=power-off" on the kernel command line. Suggested
131 * by Jim Avera <jima@hal.com>, modified by Alan Cox
132 * <alan@lxorguk.ukuu.org.uk>.
133 * Register the /proc/apm entry even on SMP so that
134 * scripts that check for it before doing power off
135 * work (Jim Avera <jima@hal.com>).
136 * 1.13: Changes for new pm_ interfaces (Andy Henroid
137 * <andy_henroid@yahoo.com>).
138 * Modularize the code.
139 * Fix the Thinkpad (again) :-( (CONFIG_APM_IGNORE_MULTIPLE_SUSPENDS
140 * is now the way life works).
141 * Fix thinko in suspend() (wrong return).
142 * Notify drivers on critical suspend.
143 * Make kapmd absorb more idle time (Pavel Machek <pavel@ucw.cz>
144 * modified by sfr).
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.
185 * APM 1.1 Reference:
187 * Intel Corporation, Microsoft Corporation. Advanced Power Management
188 * (APM) BIOS Interface Specification, Revision 1.1, September 1993.
189 * Intel Order Number 241704-001. Microsoft Part Number 781-110-X01.
191 * [This document is available free from Intel by calling 800.628.8686 (fax
192 * 916.356.6100) or 800.548.4725; or from
193 * http://www.microsoft.com/whdc/archive/amp_12.mspx It is also
194 * available from Microsoft by calling 206.882.8080.]
196 * APM 1.2 Reference:
197 * Intel Corporation, Microsoft Corporation. Advanced Power Management
198 * (APM) BIOS Interface Specification, Revision 1.2, February 1996.
200 * [This document is available from Microsoft at:
201 * http://www.microsoft.com/whdc/archive/amp_12.mspx]
204 #include <linux/module.h>
206 #include <linux/poll.h>
207 #include <linux/types.h>
208 #include <linux/stddef.h>
209 #include <linux/timer.h>
210 #include <linux/fcntl.h>
211 #include <linux/slab.h>
212 #include <linux/stat.h>
213 #include <linux/proc_fs.h>
214 #include <linux/seq_file.h>
215 #include <linux/miscdevice.h>
216 #include <linux/apm_bios.h>
217 #include <linux/init.h>
218 #include <linux/time.h>
219 #include <linux/sched.h>
220 #include <linux/pm.h>
221 #include <linux/capability.h>
222 #include <linux/device.h>
223 #include <linux/kernel.h>
224 #include <linux/freezer.h>
225 #include <linux/smp.h>
226 #include <linux/dmi.h>
227 #include <linux/suspend.h>
228 #include <linux/kthread.h>
229 #include <linux/jiffies.h>
231 #include <asm/system.h>
232 #include <asm/uaccess.h>
233 #include <asm/desc.h>
234 #include <asm/i8253.h>
235 #include <asm/olpc.h>
236 #include <asm/paravirt.h>
237 #include <asm/reboot.h>
239 #if defined(CONFIG_APM_DISPLAY_BLANK) && defined(CONFIG_VT)
240 extern int (*console_blank_hook)(int);
241 #endif
244 * The apm_bios device is one of the misc char devices.
245 * This is its minor number.
247 #define APM_MINOR_DEV 134
250 * See Documentation/Config.help for the configuration options.
252 * Various options can be changed at boot time as follows:
253 * (We allow underscores for compatibility with the modules code)
254 * apm=on/off enable/disable APM
255 * [no-]allow[-_]ints allow interrupts during BIOS calls
256 * [no-]broken[-_]psr BIOS has a broken GetPowerStatus call
257 * [no-]realmode[-_]power[-_]off switch to real mode before
258 * powering off
259 * [no-]debug log some debugging messages
260 * [no-]power[-_]off power off on shutdown
261 * [no-]smp Use apm even on an SMP box
262 * bounce[-_]interval=<n> number of ticks to ignore suspend
263 * bounces
264 * idle[-_]threshold=<n> System idle percentage above which to
265 * make APM BIOS idle calls. Set it to
266 * 100 to disable.
267 * idle[-_]period=<n> Period (in 1/100s of a second) over
268 * which the idle percentage is
269 * calculated.
272 /* KNOWN PROBLEM MACHINES:
274 * U: TI 4000M TravelMate: BIOS is *NOT* APM compliant
275 * [Confirmed by TI representative]
276 * ?: ACER 486DX4/75: uses dseg 0040, in violation of APM specification
277 * [Confirmed by BIOS disassembly]
278 * [This may work now ...]
279 * P: Toshiba 1950S: battery life information only gets updated after resume
280 * P: Midwest Micro Soundbook Elite DX2/66 monochrome: screen blanking
281 * broken in BIOS [Reported by Garst R. Reese <reese@isn.net>]
282 * ?: AcerNote-950: oops on reading /proc/apm - workaround is a WIP
283 * Neale Banks <neale@lowendale.com.au> December 2000
285 * Legend: U = unusable with APM patches
286 * P = partially usable with APM patches
290 * Define as 1 to make the driver always call the APM BIOS busy
291 * routine even if the clock was not reported as slowed by the
292 * idle routine. Otherwise, define as 0.
294 #define ALWAYS_CALL_BUSY 1
297 * Define to make the APM BIOS calls zero all data segment registers (so
298 * that an incorrect BIOS implementation will cause a kernel panic if it
299 * tries to write to arbitrary memory).
301 #define APM_ZERO_SEGS
303 #include <asm/apm.h>
306 * Define to re-initialize the interrupt 0 timer to 100 Hz after a suspend.
307 * This patched by Chad Miller <cmiller@surfsouth.com>, original code by
308 * David Chen <chen@ctpa04.mit.edu>
310 #undef INIT_TIMER_AFTER_SUSPEND
312 #ifdef INIT_TIMER_AFTER_SUSPEND
313 #include <linux/timex.h>
314 #include <asm/io.h>
315 #include <linux/delay.h>
316 #endif
319 * Need to poll the APM BIOS every second
321 #define APM_CHECK_TIMEOUT (HZ)
324 * Ignore suspend events for this amount of time after a resume
326 #define DEFAULT_BOUNCE_INTERVAL (3 * HZ)
329 * Maximum number of events stored
331 #define APM_MAX_EVENTS 20
334 * The per-file APM data
336 struct apm_user {
337 int magic;
338 struct apm_user *next;
339 unsigned int suser: 1;
340 unsigned int writer: 1;
341 unsigned int reader: 1;
342 unsigned int suspend_wait: 1;
343 int suspend_result;
344 int suspends_pending;
345 int standbys_pending;
346 int suspends_read;
347 int standbys_read;
348 int event_head;
349 int event_tail;
350 apm_event_t events[APM_MAX_EVENTS];
354 * The magic number in apm_user
356 #define APM_BIOS_MAGIC 0x4101
359 * idle percentage above which bios idle calls are done
361 #ifdef CONFIG_APM_CPU_IDLE
362 #define DEFAULT_IDLE_THRESHOLD 95
363 #else
364 #define DEFAULT_IDLE_THRESHOLD 100
365 #endif
366 #define DEFAULT_IDLE_PERIOD (100 / 3)
369 * Local variables
371 static struct {
372 unsigned long offset;
373 unsigned short segment;
374 } apm_bios_entry;
375 static int clock_slowed;
376 static int idle_threshold __read_mostly = DEFAULT_IDLE_THRESHOLD;
377 static int idle_period __read_mostly = DEFAULT_IDLE_PERIOD;
378 static int set_pm_idle;
379 static int suspends_pending;
380 static int standbys_pending;
381 static int ignore_sys_suspend;
382 static int ignore_normal_resume;
383 static int bounce_interval __read_mostly = DEFAULT_BOUNCE_INTERVAL;
385 static int debug __read_mostly;
386 static int smp __read_mostly;
387 static int apm_disabled = -1;
388 #ifdef CONFIG_SMP
389 static int power_off;
390 #else
391 static int power_off = 1;
392 #endif
393 static int realmode_power_off;
394 #ifdef CONFIG_APM_ALLOW_INTS
395 static int allow_ints = 1;
396 #else
397 static int allow_ints;
398 #endif
399 static int broken_psr;
401 static DECLARE_WAIT_QUEUE_HEAD(apm_waitqueue);
402 static DECLARE_WAIT_QUEUE_HEAD(apm_suspend_waitqueue);
403 static struct apm_user *user_list;
404 static DEFINE_SPINLOCK(user_list_lock);
405 static DEFINE_MUTEX(apm_mutex);
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[] = {
425 "system standby",
426 "system suspend",
427 "normal resume",
428 "critical resume",
429 "low battery",
430 "power status change",
431 "update time",
432 "critical suspend",
433 "user standby",
434 "user suspend",
435 "system standby resume",
436 "capabilities change"
438 #define NR_APM_EVENT_NAME ARRAY_SIZE(apm_event_name)
440 typedef struct lookup_t {
441 int key;
442 char *msg;
443 } lookup_t;
446 * The BIOS returns a set of standard error codes in AX when the
447 * carry flag is set.
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)
482 int i;
484 for (i = 0; i < ERROR_COUNT; i++)
485 if (error_table[i].key == err)
486 break;
487 if (i < ERROR_COUNT)
488 printk(KERN_NOTICE "apm: %s: %s\n", str, error_table[i].msg);
489 else if (err < 0)
490 printk(KERN_NOTICE "apm: %s: linux error code %i\n", str, err);
491 else
492 printk(KERN_NOTICE "apm: %s: unknown error code %#2.2x\n",
493 str, err);
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)
515 unsigned long flags;
516 local_save_flags(flags);
517 if (apm_info.allow_ints) {
518 if (irqs_disabled_flags(flags))
519 local_irq_enable();
520 } else
521 local_irq_disable();
523 return 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))
532 local_irq_disable();
533 else if (irqs_disabled())
534 local_irq_enable();
537 #ifdef APM_ZERO_SEGS
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)
544 #else
545 # define APM_DECL_SEGS
546 # define APM_DO_SAVE_SEGS
547 # define APM_DO_RESTORE_SEGS
548 #endif
550 struct apm_bios_call {
551 u32 func;
552 /* In and out */
553 u32 ebx;
554 u32 ecx;
555 /* Out only */
556 u32 eax;
557 u32 edx;
558 u32 esi;
560 /* Error: -ENOMEM, or bits 8-15 of eax */
561 int err;
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
574 * returns non-zero.
576 * Note: this makes the call on the current CPU.
578 static long __apm_bios_call(void *_call)
580 APM_DECL_SEGS
581 unsigned long flags;
582 int cpu;
583 struct desc_struct save_desc_40;
584 struct desc_struct *gdt;
585 struct apm_bios_call *call = _call;
587 cpu = get_cpu();
588 BUG_ON(cpu != 0);
589 gdt = get_cpu_gdt_table(cpu);
590 save_desc_40 = gdt[0x40 / 8];
591 gdt[0x40 / 8] = bad_bios_desc;
593 apm_irq_save(flags);
594 APM_DO_SAVE_SEGS;
595 apm_bios_call_asm(call->func, call->ebx, call->ecx,
596 &call->eax, &call->ebx, &call->ecx, &call->edx,
597 &call->esi);
598 APM_DO_RESTORE_SEGS;
599 apm_irq_restore(flags);
600 gdt[0x40 / 8] = save_desc_40;
601 put_cpu();
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)
609 int ret;
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) {
614 ret = fn(call);
615 put_cpu();
616 } else {
617 put_cpu();
618 ret = work_on_cpu(0, fn, call);
621 /* work_on_cpu can fail with -ENOMEM */
622 if (ret < 0)
623 call->err = ret;
624 else
625 call->err = (call->eax >> 8) & 0xff;
627 return ret;
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)
655 u8 error;
656 APM_DECL_SEGS
657 unsigned long flags;
658 int cpu;
659 struct desc_struct save_desc_40;
660 struct desc_struct *gdt;
661 struct apm_bios_call *call = _call;
663 cpu = get_cpu();
664 BUG_ON(cpu != 0);
665 gdt = get_cpu_gdt_table(cpu);
666 save_desc_40 = gdt[0x40 / 8];
667 gdt[0x40 / 8] = bad_bios_desc;
669 apm_irq_save(flags);
670 APM_DO_SAVE_SEGS;
671 error = apm_bios_call_simple_asm(call->func, call->ebx, call->ecx,
672 &call->eax);
673 APM_DO_RESTORE_SEGS;
674 apm_irq_restore(flags);
675 gdt[0x40 / 8] = save_desc_40;
676 put_cpu();
677 return error;
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
686 * @err: bits
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,
695 int *err)
697 struct apm_bios_call call;
698 int ret;
700 call.func = func;
701 call.ebx = ebx_in;
702 call.ecx = ecx_in;
704 ret = on_cpu0(__apm_bios_call_simple, &call);
705 *eax = call.eax;
706 *err = call.err;
707 return ret;
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
716 * probably present.
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
723 * same format.
726 static int apm_driver_version(u_short *val)
728 u32 eax;
729 int err;
731 if (apm_bios_call_simple(APM_FUNC_VERSION, 0, *val, &eax, &err))
732 return err;
733 *val = eax;
734 return APM_SUCCESS;
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))
761 return call.err;
763 *event = call.ebx;
764 if (apm_info.connection_version < 0x0102)
765 *info = ~0; /* indicate info not valid */
766 else
767 *info = call.ecx;
768 return APM_SUCCESS;
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)
787 u32 eax;
788 int err;
790 if (apm_bios_call_simple(APM_FUNC_SET_STATE, what, state, &eax, &err))
791 return err;
792 return APM_SUCCESS;
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)
818 u32 eax;
819 u8 ret = 0;
820 int idled = 0;
821 int polling;
822 int err = 0;
824 polling = !!(current_thread_info()->status & TS_POLLING);
825 if (polling) {
826 current_thread_info()->status &= ~TS_POLLING;
828 * TS_POLLING-cleared state must be visible before we
829 * test NEED_RESCHED:
831 smp_mb();
833 if (!need_resched()) {
834 idled = 1;
835 ret = apm_bios_call_simple(APM_FUNC_IDLE, 0, 0, &eax, &err);
837 if (polling)
838 current_thread_info()->status |= TS_POLLING;
840 if (!idled)
841 return 0;
843 if (ret) {
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.
849 if (++t < 5) {
850 printk(KERN_DEBUG "apm_do_idle failed (%d)\n", err);
851 t = jiffies;
853 return -1;
855 clock_slowed = (apm_info.bios.flags & APM_IDLE_SLOWS_CLOCK) != 0;
856 return clock_slowed;
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)
867 u32 dummy;
868 int err;
870 if (clock_slowed || ALWAYS_CALL_BUSY) {
871 (void)apm_bios_call_simple(APM_FUNC_BUSY, 0, 0, &dummy, &err);
872 clock_slowed = 0;
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
880 * to conserve power.
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;
903 unsigned int bucket;
905 recalc:
906 if (jiffies_since_last_check > IDLE_CALC_LIMIT) {
907 use_apm_idle = 0;
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)
918 use_apm_idle = 0;
919 last_jiffies = jiffies;
920 last_stime = current->stime;
923 bucket = IDLE_LEAKY_MAX;
925 while (!need_resched()) {
926 if (use_apm_idle) {
927 unsigned int t;
929 t = jiffies;
930 switch (apm_do_idle()) {
931 case 0:
932 apm_idle_done = 1;
933 if (t != jiffies) {
934 if (bucket) {
935 bucket = IDLE_LEAKY_MAX;
936 continue;
938 } else if (bucket) {
939 bucket--;
940 continue;
942 break;
943 case 1:
944 apm_idle_done = 1;
945 break;
946 default: /* BIOS refused */
947 break;
950 if (original_pm_idle)
951 original_pm_idle();
952 else
953 default_idle();
954 local_irq_disable();
955 jiffies_since_last_check = jiffies - last_jiffies;
956 if (jiffies_since_last_check > idle_period)
957 goto recalc;
960 if (apm_idle_done)
961 apm_do_busy();
963 local_irq_enable();
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 /* Some bioses don't like being called from CPU != 0 */
979 if (apm_info.realmode_power_off) {
980 set_cpus_allowed_ptr(current, cpumask_of(0));
981 machine_real_restart(MRR_APM);
982 } else {
983 (void)set_system_power_state(APM_STATE_OFF);
987 #ifdef CONFIG_APM_DO_ENABLE
990 * apm_enable_power_management - enable BIOS APM power management
991 * @enable: enable yes/no
993 * Enable or disable the APM BIOS power services.
996 static int apm_enable_power_management(int enable)
998 u32 eax;
999 int err;
1001 if ((enable == 0) && (apm_info.bios.flags & APM_BIOS_DISENGAGED))
1002 return APM_NOT_ENGAGED;
1003 if (apm_bios_call_simple(APM_FUNC_ENABLE_PM, APM_DEVICE_BALL,
1004 enable, &eax, &err))
1005 return err;
1006 if (enable)
1007 apm_info.bios.flags &= ~APM_BIOS_DISABLED;
1008 else
1009 apm_info.bios.flags |= APM_BIOS_DISABLED;
1010 return APM_SUCCESS;
1012 #endif
1015 * apm_get_power_status - get current power state
1016 * @status: returned status
1017 * @bat: battery info
1018 * @life: estimated life
1020 * Obtain the current power status from the APM BIOS. We return a
1021 * status which gives the rough battery status, and current power
1022 * source. The bat value returned give an estimate as a percentage
1023 * of life and a status value for the battery. The estimated life
1024 * if reported is a lifetime in secodnds/minutes at current powwer
1025 * consumption.
1028 static int apm_get_power_status(u_short *status, u_short *bat, u_short *life)
1030 struct apm_bios_call call;
1032 call.func = APM_FUNC_GET_STATUS;
1033 call.ebx = APM_DEVICE_ALL;
1034 call.ecx = 0;
1036 if (apm_info.get_power_status_broken)
1037 return APM_32_UNSUPPORTED;
1038 if (apm_bios_call(&call))
1039 return call.err;
1040 *status = call.ebx;
1041 *bat = call.ecx;
1042 if (apm_info.get_power_status_swabinminutes) {
1043 *life = swab16((u16)call.edx);
1044 *life |= 0x8000;
1045 } else
1046 *life = call.edx;
1047 return APM_SUCCESS;
1050 #if 0
1051 static int apm_get_battery_status(u_short which, u_short *status,
1052 u_short *bat, u_short *life, u_short *nbat)
1054 u32 eax;
1055 u32 ebx;
1056 u32 ecx;
1057 u32 edx;
1058 u32 esi;
1060 if (apm_info.connection_version < 0x0102) {
1061 /* pretend we only have one battery. */
1062 if (which != 1)
1063 return APM_BAD_DEVICE;
1064 *nbat = 1;
1065 return apm_get_power_status(status, bat, life);
1068 if (apm_bios_call(APM_FUNC_GET_STATUS, (0x8000 | (which)), 0, &eax,
1069 &ebx, &ecx, &edx, &esi))
1070 return (eax >> 8) & 0xff;
1071 *status = ebx;
1072 *bat = ecx;
1073 *life = edx;
1074 *nbat = esi;
1075 return APM_SUCCESS;
1077 #endif
1080 * apm_engage_power_management - enable PM on a device
1081 * @device: identity of device
1082 * @enable: on/off
1084 * Activate or deactive power management on either a specific device
1085 * or the entire system (%APM_DEVICE_ALL).
1088 static int apm_engage_power_management(u_short device, int enable)
1090 u32 eax;
1091 int err;
1093 if ((enable == 0) && (device == APM_DEVICE_ALL)
1094 && (apm_info.bios.flags & APM_BIOS_DISABLED))
1095 return APM_DISABLED;
1096 if (apm_bios_call_simple(APM_FUNC_ENGAGE_PM, device, enable,
1097 &eax, &err))
1098 return err;
1099 if (device == APM_DEVICE_ALL) {
1100 if (enable)
1101 apm_info.bios.flags &= ~APM_BIOS_DISENGAGED;
1102 else
1103 apm_info.bios.flags |= APM_BIOS_DISENGAGED;
1105 return APM_SUCCESS;
1108 #if defined(CONFIG_APM_DISPLAY_BLANK) && defined(CONFIG_VT)
1111 * apm_console_blank - blank the display
1112 * @blank: on/off
1114 * Attempt to blank the console, firstly by blanking just video device
1115 * zero, and if that fails (some BIOSes don't support it) then it blanks
1116 * all video devices. Typically the BIOS will do laptop backlight and
1117 * monitor powerdown for us.
1120 static int apm_console_blank(int blank)
1122 int error = APM_NOT_ENGAGED; /* silence gcc */
1123 int i;
1124 u_short state;
1125 static const u_short dev[3] = { 0x100, 0x1FF, 0x101 };
1127 state = blank ? APM_STATE_STANDBY : APM_STATE_READY;
1129 for (i = 0; i < ARRAY_SIZE(dev); i++) {
1130 error = set_power_state(dev[i], state);
1132 if ((error == APM_SUCCESS) || (error == APM_NO_ERROR))
1133 return 1;
1135 if (error == APM_NOT_ENGAGED)
1136 break;
1139 if (error == APM_NOT_ENGAGED) {
1140 static int tried;
1141 int eng_error;
1142 if (tried++ == 0) {
1143 eng_error = apm_engage_power_management(APM_DEVICE_ALL, 1);
1144 if (eng_error) {
1145 apm_error("set display", error);
1146 apm_error("engage interface", eng_error);
1147 return 0;
1148 } else
1149 return apm_console_blank(blank);
1152 apm_error("set display", error);
1153 return 0;
1155 #endif
1157 static int queue_empty(struct apm_user *as)
1159 return as->event_head == as->event_tail;
1162 static apm_event_t get_queued_event(struct apm_user *as)
1164 if (++as->event_tail >= APM_MAX_EVENTS)
1165 as->event_tail = 0;
1166 return as->events[as->event_tail];
1169 static void queue_event(apm_event_t event, struct apm_user *sender)
1171 struct apm_user *as;
1173 spin_lock(&user_list_lock);
1174 if (user_list == NULL)
1175 goto out;
1176 for (as = user_list; as != NULL; as = as->next) {
1177 if ((as == sender) || (!as->reader))
1178 continue;
1179 if (++as->event_head >= APM_MAX_EVENTS)
1180 as->event_head = 0;
1182 if (as->event_head == as->event_tail) {
1183 static int notified;
1185 if (notified++ == 0)
1186 printk(KERN_ERR "apm: an event queue overflowed\n");
1187 if (++as->event_tail >= APM_MAX_EVENTS)
1188 as->event_tail = 0;
1190 as->events[as->event_head] = event;
1191 if (!as->suser || !as->writer)
1192 continue;
1193 switch (event) {
1194 case APM_SYS_SUSPEND:
1195 case APM_USER_SUSPEND:
1196 as->suspends_pending++;
1197 suspends_pending++;
1198 break;
1200 case APM_SYS_STANDBY:
1201 case APM_USER_STANDBY:
1202 as->standbys_pending++;
1203 standbys_pending++;
1204 break;
1207 wake_up_interruptible(&apm_waitqueue);
1208 out:
1209 spin_unlock(&user_list_lock);
1212 static void reinit_timer(void)
1214 #ifdef INIT_TIMER_AFTER_SUSPEND
1215 unsigned long flags;
1217 raw_spin_lock_irqsave(&i8253_lock, flags);
1218 /* set the clock to HZ */
1219 outb_pit(0x34, PIT_MODE); /* binary, mode 2, LSB/MSB, ch 0 */
1220 udelay(10);
1221 outb_pit(LATCH & 0xff, PIT_CH0); /* LSB */
1222 udelay(10);
1223 outb_pit(LATCH >> 8, PIT_CH0); /* MSB */
1224 udelay(10);
1225 raw_spin_unlock_irqrestore(&i8253_lock, flags);
1226 #endif
1229 static int suspend(int vetoable)
1231 int err;
1232 struct apm_user *as;
1234 dpm_suspend_start(PMSG_SUSPEND);
1236 dpm_suspend_noirq(PMSG_SUSPEND);
1238 local_irq_disable();
1239 sysdev_suspend(PMSG_SUSPEND);
1241 local_irq_enable();
1243 save_processor_state();
1244 err = set_system_power_state(APM_STATE_SUSPEND);
1245 ignore_normal_resume = 1;
1246 restore_processor_state();
1248 local_irq_disable();
1249 reinit_timer();
1251 if (err == APM_NO_ERROR)
1252 err = APM_SUCCESS;
1253 if (err != APM_SUCCESS)
1254 apm_error("suspend", err);
1255 err = (err == APM_SUCCESS) ? 0 : -EIO;
1257 sysdev_resume();
1258 local_irq_enable();
1260 dpm_resume_noirq(PMSG_RESUME);
1262 dpm_resume_end(PMSG_RESUME);
1263 queue_event(APM_NORMAL_RESUME, NULL);
1264 spin_lock(&user_list_lock);
1265 for (as = user_list; as != NULL; as = as->next) {
1266 as->suspend_wait = 0;
1267 as->suspend_result = err;
1269 spin_unlock(&user_list_lock);
1270 wake_up_interruptible(&apm_suspend_waitqueue);
1271 return err;
1274 static void standby(void)
1276 int err;
1278 dpm_suspend_noirq(PMSG_SUSPEND);
1280 local_irq_disable();
1281 sysdev_suspend(PMSG_SUSPEND);
1282 local_irq_enable();
1284 err = set_system_power_state(APM_STATE_STANDBY);
1285 if ((err != APM_SUCCESS) && (err != APM_NO_ERROR))
1286 apm_error("standby", err);
1288 local_irq_disable();
1289 sysdev_resume();
1290 local_irq_enable();
1292 dpm_resume_noirq(PMSG_RESUME);
1295 static apm_event_t get_event(void)
1297 int error;
1298 apm_event_t event = APM_NO_EVENTS; /* silence gcc */
1299 apm_eventinfo_t info;
1301 static int notified;
1303 /* we don't use the eventinfo */
1304 error = apm_get_event(&event, &info);
1305 if (error == APM_SUCCESS)
1306 return event;
1308 if ((error != APM_NO_EVENTS) && (notified++ == 0))
1309 apm_error("get_event", error);
1311 return 0;
1314 static void check_events(void)
1316 apm_event_t event;
1317 static unsigned long last_resume;
1318 static int ignore_bounce;
1320 while ((event = get_event()) != 0) {
1321 if (debug) {
1322 if (event <= NR_APM_EVENT_NAME)
1323 printk(KERN_DEBUG "apm: received %s notify\n",
1324 apm_event_name[event - 1]);
1325 else
1326 printk(KERN_DEBUG "apm: received unknown "
1327 "event 0x%02x\n", event);
1329 if (ignore_bounce
1330 && (time_after(jiffies, last_resume + bounce_interval)))
1331 ignore_bounce = 0;
1333 switch (event) {
1334 case APM_SYS_STANDBY:
1335 case APM_USER_STANDBY:
1336 queue_event(event, NULL);
1337 if (standbys_pending <= 0)
1338 standby();
1339 break;
1341 case APM_USER_SUSPEND:
1342 #ifdef CONFIG_APM_IGNORE_USER_SUSPEND
1343 if (apm_info.connection_version > 0x100)
1344 set_system_power_state(APM_STATE_REJECT);
1345 break;
1346 #endif
1347 case APM_SYS_SUSPEND:
1348 if (ignore_bounce) {
1349 if (apm_info.connection_version > 0x100)
1350 set_system_power_state(APM_STATE_REJECT);
1351 break;
1354 * If we are already processing a SUSPEND,
1355 * then further SUSPEND events from the BIOS
1356 * will be ignored. We also return here to
1357 * cope with the fact that the Thinkpads keep
1358 * sending a SUSPEND event until something else
1359 * happens!
1361 if (ignore_sys_suspend)
1362 return;
1363 ignore_sys_suspend = 1;
1364 queue_event(event, NULL);
1365 if (suspends_pending <= 0)
1366 (void) suspend(1);
1367 break;
1369 case APM_NORMAL_RESUME:
1370 case APM_CRITICAL_RESUME:
1371 case APM_STANDBY_RESUME:
1372 ignore_sys_suspend = 0;
1373 last_resume = jiffies;
1374 ignore_bounce = 1;
1375 if ((event != APM_NORMAL_RESUME)
1376 || (ignore_normal_resume == 0)) {
1377 dpm_resume_end(PMSG_RESUME);
1378 queue_event(event, NULL);
1380 ignore_normal_resume = 0;
1381 break;
1383 case APM_CAPABILITY_CHANGE:
1384 case APM_LOW_BATTERY:
1385 case APM_POWER_STATUS_CHANGE:
1386 queue_event(event, NULL);
1387 /* If needed, notify drivers here */
1388 break;
1390 case APM_UPDATE_TIME:
1391 break;
1393 case APM_CRITICAL_SUSPEND:
1395 * We are not allowed to reject a critical suspend.
1397 (void)suspend(0);
1398 break;
1403 static void apm_event_handler(void)
1405 static int pending_count = 4;
1406 int err;
1408 if ((standbys_pending > 0) || (suspends_pending > 0)) {
1409 if ((apm_info.connection_version > 0x100) &&
1410 (pending_count-- <= 0)) {
1411 pending_count = 4;
1412 if (debug)
1413 printk(KERN_DEBUG "apm: setting state busy\n");
1414 err = set_system_power_state(APM_STATE_BUSY);
1415 if (err)
1416 apm_error("busy", err);
1418 } else
1419 pending_count = 4;
1420 check_events();
1424 * This is the APM thread main loop.
1427 static void apm_mainloop(void)
1429 DECLARE_WAITQUEUE(wait, current);
1431 add_wait_queue(&apm_waitqueue, &wait);
1432 set_current_state(TASK_INTERRUPTIBLE);
1433 for (;;) {
1434 schedule_timeout(APM_CHECK_TIMEOUT);
1435 if (kthread_should_stop())
1436 break;
1438 * Ok, check all events, check for idle (and mark us sleeping
1439 * so as not to count towards the load average)..
1441 set_current_state(TASK_INTERRUPTIBLE);
1442 apm_event_handler();
1444 remove_wait_queue(&apm_waitqueue, &wait);
1447 static int check_apm_user(struct apm_user *as, const char *func)
1449 if (as == NULL || as->magic != APM_BIOS_MAGIC) {
1450 printk(KERN_ERR "apm: %s passed bad filp\n", func);
1451 return 1;
1453 return 0;
1456 static ssize_t do_read(struct file *fp, char __user *buf, size_t count, loff_t *ppos)
1458 struct apm_user *as;
1459 int i;
1460 apm_event_t event;
1462 as = fp->private_data;
1463 if (check_apm_user(as, "read"))
1464 return -EIO;
1465 if ((int)count < sizeof(apm_event_t))
1466 return -EINVAL;
1467 if ((queue_empty(as)) && (fp->f_flags & O_NONBLOCK))
1468 return -EAGAIN;
1469 wait_event_interruptible(apm_waitqueue, !queue_empty(as));
1470 i = count;
1471 while ((i >= sizeof(event)) && !queue_empty(as)) {
1472 event = get_queued_event(as);
1473 if (copy_to_user(buf, &event, sizeof(event))) {
1474 if (i < count)
1475 break;
1476 return -EFAULT;
1478 switch (event) {
1479 case APM_SYS_SUSPEND:
1480 case APM_USER_SUSPEND:
1481 as->suspends_read++;
1482 break;
1484 case APM_SYS_STANDBY:
1485 case APM_USER_STANDBY:
1486 as->standbys_read++;
1487 break;
1489 buf += sizeof(event);
1490 i -= sizeof(event);
1492 if (i < count)
1493 return count - i;
1494 if (signal_pending(current))
1495 return -ERESTARTSYS;
1496 return 0;
1499 static unsigned int do_poll(struct file *fp, poll_table *wait)
1501 struct apm_user *as;
1503 as = fp->private_data;
1504 if (check_apm_user(as, "poll"))
1505 return 0;
1506 poll_wait(fp, &apm_waitqueue, wait);
1507 if (!queue_empty(as))
1508 return POLLIN | POLLRDNORM;
1509 return 0;
1512 static long do_ioctl(struct file *filp, u_int cmd, u_long arg)
1514 struct apm_user *as;
1515 int ret;
1517 as = filp->private_data;
1518 if (check_apm_user(as, "ioctl"))
1519 return -EIO;
1520 if (!as->suser || !as->writer)
1521 return -EPERM;
1522 switch (cmd) {
1523 case APM_IOC_STANDBY:
1524 mutex_lock(&apm_mutex);
1525 if (as->standbys_read > 0) {
1526 as->standbys_read--;
1527 as->standbys_pending--;
1528 standbys_pending--;
1529 } else
1530 queue_event(APM_USER_STANDBY, as);
1531 if (standbys_pending <= 0)
1532 standby();
1533 mutex_unlock(&apm_mutex);
1534 break;
1535 case APM_IOC_SUSPEND:
1536 mutex_lock(&apm_mutex);
1537 if (as->suspends_read > 0) {
1538 as->suspends_read--;
1539 as->suspends_pending--;
1540 suspends_pending--;
1541 } else
1542 queue_event(APM_USER_SUSPEND, as);
1543 if (suspends_pending <= 0) {
1544 ret = suspend(1);
1545 mutex_unlock(&apm_mutex);
1546 } else {
1547 as->suspend_wait = 1;
1548 mutex_unlock(&apm_mutex);
1549 wait_event_interruptible(apm_suspend_waitqueue,
1550 as->suspend_wait == 0);
1551 ret = as->suspend_result;
1553 return ret;
1554 default:
1555 return -ENOTTY;
1557 return 0;
1560 static int do_release(struct inode *inode, struct file *filp)
1562 struct apm_user *as;
1564 as = filp->private_data;
1565 if (check_apm_user(as, "release"))
1566 return 0;
1567 filp->private_data = NULL;
1568 if (as->standbys_pending > 0) {
1569 standbys_pending -= as->standbys_pending;
1570 if (standbys_pending <= 0)
1571 standby();
1573 if (as->suspends_pending > 0) {
1574 suspends_pending -= as->suspends_pending;
1575 if (suspends_pending <= 0)
1576 (void) suspend(1);
1578 spin_lock(&user_list_lock);
1579 if (user_list == as)
1580 user_list = as->next;
1581 else {
1582 struct apm_user *as1;
1584 for (as1 = user_list;
1585 (as1 != NULL) && (as1->next != as);
1586 as1 = as1->next)
1588 if (as1 == NULL)
1589 printk(KERN_ERR "apm: filp not in user list\n");
1590 else
1591 as1->next = as->next;
1593 spin_unlock(&user_list_lock);
1594 kfree(as);
1595 return 0;
1598 static int do_open(struct inode *inode, struct file *filp)
1600 struct apm_user *as;
1602 as = kmalloc(sizeof(*as), GFP_KERNEL);
1603 if (as == NULL) {
1604 printk(KERN_ERR "apm: cannot allocate struct of size %d bytes\n",
1605 sizeof(*as));
1606 return -ENOMEM;
1608 as->magic = APM_BIOS_MAGIC;
1609 as->event_tail = as->event_head = 0;
1610 as->suspends_pending = as->standbys_pending = 0;
1611 as->suspends_read = as->standbys_read = 0;
1613 * XXX - this is a tiny bit broken, when we consider BSD
1614 * process accounting. If the device is opened by root, we
1615 * instantly flag that we used superuser privs. Who knows,
1616 * we might close the device immediately without doing a
1617 * privileged operation -- cevans
1619 as->suser = capable(CAP_SYS_ADMIN);
1620 as->writer = (filp->f_mode & FMODE_WRITE) == FMODE_WRITE;
1621 as->reader = (filp->f_mode & FMODE_READ) == FMODE_READ;
1622 spin_lock(&user_list_lock);
1623 as->next = user_list;
1624 user_list = as;
1625 spin_unlock(&user_list_lock);
1626 filp->private_data = as;
1627 return 0;
1630 static int proc_apm_show(struct seq_file *m, void *v)
1632 unsigned short bx;
1633 unsigned short cx;
1634 unsigned short dx;
1635 int error;
1636 unsigned short ac_line_status = 0xff;
1637 unsigned short battery_status = 0xff;
1638 unsigned short battery_flag = 0xff;
1639 int percentage = -1;
1640 int time_units = -1;
1641 char *units = "?";
1643 if ((num_online_cpus() == 1) &&
1644 !(error = apm_get_power_status(&bx, &cx, &dx))) {
1645 ac_line_status = (bx >> 8) & 0xff;
1646 battery_status = bx & 0xff;
1647 if ((cx & 0xff) != 0xff)
1648 percentage = cx & 0xff;
1650 if (apm_info.connection_version > 0x100) {
1651 battery_flag = (cx >> 8) & 0xff;
1652 if (dx != 0xffff) {
1653 units = (dx & 0x8000) ? "min" : "sec";
1654 time_units = dx & 0x7fff;
1658 /* Arguments, with symbols from linux/apm_bios.h. Information is
1659 from the Get Power Status (0x0a) call unless otherwise noted.
1661 0) Linux driver version (this will change if format changes)
1662 1) APM BIOS Version. Usually 1.0, 1.1 or 1.2.
1663 2) APM flags from APM Installation Check (0x00):
1664 bit 0: APM_16_BIT_SUPPORT
1665 bit 1: APM_32_BIT_SUPPORT
1666 bit 2: APM_IDLE_SLOWS_CLOCK
1667 bit 3: APM_BIOS_DISABLED
1668 bit 4: APM_BIOS_DISENGAGED
1669 3) AC line status
1670 0x00: Off-line
1671 0x01: On-line
1672 0x02: On backup power (BIOS >= 1.1 only)
1673 0xff: Unknown
1674 4) Battery status
1675 0x00: High
1676 0x01: Low
1677 0x02: Critical
1678 0x03: Charging
1679 0x04: Selected battery not present (BIOS >= 1.2 only)
1680 0xff: Unknown
1681 5) Battery flag
1682 bit 0: High
1683 bit 1: Low
1684 bit 2: Critical
1685 bit 3: Charging
1686 bit 7: No system battery
1687 0xff: Unknown
1688 6) Remaining battery life (percentage of charge):
1689 0-100: valid
1690 -1: Unknown
1691 7) Remaining battery life (time units):
1692 Number of remaining minutes or seconds
1693 -1: Unknown
1694 8) min = minutes; sec = seconds */
1696 seq_printf(m, "%s %d.%d 0x%02x 0x%02x 0x%02x 0x%02x %d%% %d %s\n",
1697 driver_version,
1698 (apm_info.bios.version >> 8) & 0xff,
1699 apm_info.bios.version & 0xff,
1700 apm_info.bios.flags,
1701 ac_line_status,
1702 battery_status,
1703 battery_flag,
1704 percentage,
1705 time_units,
1706 units);
1707 return 0;
1710 static int proc_apm_open(struct inode *inode, struct file *file)
1712 return single_open(file, proc_apm_show, NULL);
1715 static const struct file_operations apm_file_ops = {
1716 .owner = THIS_MODULE,
1717 .open = proc_apm_open,
1718 .read = seq_read,
1719 .llseek = seq_lseek,
1720 .release = single_release,
1723 static int apm(void *unused)
1725 unsigned short bx;
1726 unsigned short cx;
1727 unsigned short dx;
1728 int error;
1729 char *power_stat;
1730 char *bat_stat;
1732 /* 2002/08/01 - WT
1733 * This is to avoid random crashes at boot time during initialization
1734 * on SMP systems in case of "apm=power-off" mode. Seen on ASUS A7M266D.
1735 * Some bioses don't like being called from CPU != 0.
1736 * Method suggested by Ingo Molnar.
1738 set_cpus_allowed_ptr(current, cpumask_of(0));
1739 BUG_ON(smp_processor_id() != 0);
1741 if (apm_info.connection_version == 0) {
1742 apm_info.connection_version = apm_info.bios.version;
1743 if (apm_info.connection_version > 0x100) {
1745 * We only support BIOSs up to version 1.2
1747 if (apm_info.connection_version > 0x0102)
1748 apm_info.connection_version = 0x0102;
1749 error = apm_driver_version(&apm_info.connection_version);
1750 if (error != APM_SUCCESS) {
1751 apm_error("driver version", error);
1752 /* Fall back to an APM 1.0 connection. */
1753 apm_info.connection_version = 0x100;
1758 if (debug)
1759 printk(KERN_INFO "apm: Connection version %d.%d\n",
1760 (apm_info.connection_version >> 8) & 0xff,
1761 apm_info.connection_version & 0xff);
1763 #ifdef CONFIG_APM_DO_ENABLE
1764 if (apm_info.bios.flags & APM_BIOS_DISABLED) {
1766 * This call causes my NEC UltraLite Versa 33/C to hang if it
1767 * is booted with PM disabled but not in the docking station.
1768 * Unfortunate ...
1770 error = apm_enable_power_management(1);
1771 if (error) {
1772 apm_error("enable power management", error);
1773 return -1;
1776 #endif
1778 if ((apm_info.bios.flags & APM_BIOS_DISENGAGED)
1779 && (apm_info.connection_version > 0x0100)) {
1780 error = apm_engage_power_management(APM_DEVICE_ALL, 1);
1781 if (error) {
1782 apm_error("engage power management", error);
1783 return -1;
1787 if (debug && (num_online_cpus() == 1 || smp)) {
1788 error = apm_get_power_status(&bx, &cx, &dx);
1789 if (error)
1790 printk(KERN_INFO "apm: power status not available\n");
1791 else {
1792 switch ((bx >> 8) & 0xff) {
1793 case 0:
1794 power_stat = "off line";
1795 break;
1796 case 1:
1797 power_stat = "on line";
1798 break;
1799 case 2:
1800 power_stat = "on backup power";
1801 break;
1802 default:
1803 power_stat = "unknown";
1804 break;
1806 switch (bx & 0xff) {
1807 case 0:
1808 bat_stat = "high";
1809 break;
1810 case 1:
1811 bat_stat = "low";
1812 break;
1813 case 2:
1814 bat_stat = "critical";
1815 break;
1816 case 3:
1817 bat_stat = "charging";
1818 break;
1819 default:
1820 bat_stat = "unknown";
1821 break;
1823 printk(KERN_INFO
1824 "apm: AC %s, battery status %s, battery life ",
1825 power_stat, bat_stat);
1826 if ((cx & 0xff) == 0xff)
1827 printk("unknown\n");
1828 else
1829 printk("%d%%\n", cx & 0xff);
1830 if (apm_info.connection_version > 0x100) {
1831 printk(KERN_INFO
1832 "apm: battery flag 0x%02x, battery life ",
1833 (cx >> 8) & 0xff);
1834 if (dx == 0xffff)
1835 printk("unknown\n");
1836 else
1837 printk("%d %s\n", dx & 0x7fff,
1838 (dx & 0x8000) ?
1839 "minutes" : "seconds");
1844 /* Install our power off handler.. */
1845 if (power_off)
1846 pm_power_off = apm_power_off;
1848 if (num_online_cpus() == 1 || smp) {
1849 #if defined(CONFIG_APM_DISPLAY_BLANK) && defined(CONFIG_VT)
1850 console_blank_hook = apm_console_blank;
1851 #endif
1852 apm_mainloop();
1853 #if defined(CONFIG_APM_DISPLAY_BLANK) && defined(CONFIG_VT)
1854 console_blank_hook = NULL;
1855 #endif
1858 return 0;
1861 #ifndef MODULE
1862 static int __init apm_setup(char *str)
1864 int invert;
1866 while ((str != NULL) && (*str != '\0')) {
1867 if (strncmp(str, "off", 3) == 0)
1868 apm_disabled = 1;
1869 if (strncmp(str, "on", 2) == 0)
1870 apm_disabled = 0;
1871 if ((strncmp(str, "bounce-interval=", 16) == 0) ||
1872 (strncmp(str, "bounce_interval=", 16) == 0))
1873 bounce_interval = simple_strtol(str + 16, NULL, 0);
1874 if ((strncmp(str, "idle-threshold=", 15) == 0) ||
1875 (strncmp(str, "idle_threshold=", 15) == 0))
1876 idle_threshold = simple_strtol(str + 15, NULL, 0);
1877 if ((strncmp(str, "idle-period=", 12) == 0) ||
1878 (strncmp(str, "idle_period=", 12) == 0))
1879 idle_period = simple_strtol(str + 12, NULL, 0);
1880 invert = (strncmp(str, "no-", 3) == 0) ||
1881 (strncmp(str, "no_", 3) == 0);
1882 if (invert)
1883 str += 3;
1884 if (strncmp(str, "debug", 5) == 0)
1885 debug = !invert;
1886 if ((strncmp(str, "power-off", 9) == 0) ||
1887 (strncmp(str, "power_off", 9) == 0))
1888 power_off = !invert;
1889 if (strncmp(str, "smp", 3) == 0) {
1890 smp = !invert;
1891 idle_threshold = 100;
1893 if ((strncmp(str, "allow-ints", 10) == 0) ||
1894 (strncmp(str, "allow_ints", 10) == 0))
1895 apm_info.allow_ints = !invert;
1896 if ((strncmp(str, "broken-psr", 10) == 0) ||
1897 (strncmp(str, "broken_psr", 10) == 0))
1898 apm_info.get_power_status_broken = !invert;
1899 if ((strncmp(str, "realmode-power-off", 18) == 0) ||
1900 (strncmp(str, "realmode_power_off", 18) == 0))
1901 apm_info.realmode_power_off = !invert;
1902 str = strchr(str, ',');
1903 if (str != NULL)
1904 str += strspn(str, ", \t");
1906 return 1;
1909 __setup("apm=", apm_setup);
1910 #endif
1912 static const struct file_operations apm_bios_fops = {
1913 .owner = THIS_MODULE,
1914 .read = do_read,
1915 .poll = do_poll,
1916 .unlocked_ioctl = do_ioctl,
1917 .open = do_open,
1918 .release = do_release,
1919 .llseek = noop_llseek,
1922 static struct miscdevice apm_device = {
1923 APM_MINOR_DEV,
1924 "apm_bios",
1925 &apm_bios_fops
1929 /* Simple "print if true" callback */
1930 static int __init print_if_true(const struct dmi_system_id *d)
1932 printk("%s\n", d->ident);
1933 return 0;
1937 * Some Bioses enable the PS/2 mouse (touchpad) at resume, even if it was
1938 * disabled before the suspend. Linux used to get terribly confused by that.
1940 static int __init broken_ps2_resume(const struct dmi_system_id *d)
1942 printk(KERN_INFO "%s machine detected. Mousepad Resume Bug "
1943 "workaround hopefully not needed.\n", d->ident);
1944 return 0;
1947 /* Some bioses have a broken protected mode poweroff and need to use realmode */
1948 static int __init set_realmode_power_off(const struct dmi_system_id *d)
1950 if (apm_info.realmode_power_off == 0) {
1951 apm_info.realmode_power_off = 1;
1952 printk(KERN_INFO "%s bios detected. "
1953 "Using realmode poweroff only.\n", d->ident);
1955 return 0;
1958 /* Some laptops require interrupts to be enabled during APM calls */
1959 static int __init set_apm_ints(const struct dmi_system_id *d)
1961 if (apm_info.allow_ints == 0) {
1962 apm_info.allow_ints = 1;
1963 printk(KERN_INFO "%s machine detected. "
1964 "Enabling interrupts during APM calls.\n", d->ident);
1966 return 0;
1969 /* Some APM bioses corrupt memory or just plain do not work */
1970 static int __init apm_is_horked(const struct dmi_system_id *d)
1972 if (apm_info.disabled == 0) {
1973 apm_info.disabled = 1;
1974 printk(KERN_INFO "%s machine detected. "
1975 "Disabling APM.\n", d->ident);
1977 return 0;
1980 static int __init apm_is_horked_d850md(const struct dmi_system_id *d)
1982 if (apm_info.disabled == 0) {
1983 apm_info.disabled = 1;
1984 printk(KERN_INFO "%s machine detected. "
1985 "Disabling APM.\n", d->ident);
1986 printk(KERN_INFO "This bug is fixed in bios P15 which is available for\n");
1987 printk(KERN_INFO "download from support.intel.com\n");
1989 return 0;
1992 /* Some APM bioses hang on APM idle calls */
1993 static int __init apm_likes_to_melt(const struct dmi_system_id *d)
1995 if (apm_info.forbid_idle == 0) {
1996 apm_info.forbid_idle = 1;
1997 printk(KERN_INFO "%s machine detected. "
1998 "Disabling APM idle calls.\n", d->ident);
2000 return 0;
2004 * Check for clue free BIOS implementations who use
2005 * the following QA technique
2007 * [ Write BIOS Code ]<------
2008 * | ^
2009 * < Does it Compile >----N--
2010 * |Y ^
2011 * < Does it Boot Win98 >-N--
2012 * |Y
2013 * [Ship It]
2015 * Phoenix A04 08/24/2000 is known bad (Dell Inspiron 5000e)
2016 * Phoenix A07 09/29/2000 is known good (Dell Inspiron 5000)
2018 static int __init broken_apm_power(const struct dmi_system_id *d)
2020 apm_info.get_power_status_broken = 1;
2021 printk(KERN_WARNING "BIOS strings suggest APM bugs, "
2022 "disabling power status reporting.\n");
2023 return 0;
2027 * This bios swaps the APM minute reporting bytes over (Many sony laptops
2028 * have this problem).
2030 static int __init swab_apm_power_in_minutes(const struct dmi_system_id *d)
2032 apm_info.get_power_status_swabinminutes = 1;
2033 printk(KERN_WARNING "BIOS strings suggest APM reports battery life "
2034 "in minutes and wrong byte order.\n");
2035 return 0;
2038 static struct dmi_system_id __initdata apm_dmi_table[] = {
2040 print_if_true,
2041 KERN_WARNING "IBM T23 - BIOS 1.03b+ and controller firmware 1.02+ may be needed for Linux APM.",
2042 { DMI_MATCH(DMI_SYS_VENDOR, "IBM"),
2043 DMI_MATCH(DMI_BIOS_VERSION, "1AET38WW (1.01b)"), },
2045 { /* Handle problems with APM on the C600 */
2046 broken_ps2_resume, "Dell Latitude C600",
2047 { DMI_MATCH(DMI_SYS_VENDOR, "Dell"),
2048 DMI_MATCH(DMI_PRODUCT_NAME, "Latitude C600"), },
2050 { /* Allow interrupts during suspend on Dell Latitude laptops*/
2051 set_apm_ints, "Dell Latitude",
2052 { DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
2053 DMI_MATCH(DMI_PRODUCT_NAME, "Latitude C510"), }
2055 { /* APM crashes */
2056 apm_is_horked, "Dell Inspiron 2500",
2057 { DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
2058 DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 2500"),
2059 DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2060 DMI_MATCH(DMI_BIOS_VERSION, "A11"), },
2062 { /* Allow interrupts during suspend on Dell Inspiron laptops*/
2063 set_apm_ints, "Dell Inspiron", {
2064 DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
2065 DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 4000"), },
2067 { /* Handle problems with APM on Inspiron 5000e */
2068 broken_apm_power, "Dell Inspiron 5000e",
2069 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2070 DMI_MATCH(DMI_BIOS_VERSION, "A04"),
2071 DMI_MATCH(DMI_BIOS_DATE, "08/24/2000"), },
2073 { /* Handle problems with APM on Inspiron 2500 */
2074 broken_apm_power, "Dell Inspiron 2500",
2075 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2076 DMI_MATCH(DMI_BIOS_VERSION, "A12"),
2077 DMI_MATCH(DMI_BIOS_DATE, "02/04/2002"), },
2079 { /* APM crashes */
2080 apm_is_horked, "Dell Dimension 4100",
2081 { DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
2082 DMI_MATCH(DMI_PRODUCT_NAME, "XPS-Z"),
2083 DMI_MATCH(DMI_BIOS_VENDOR, "Intel Corp."),
2084 DMI_MATCH(DMI_BIOS_VERSION, "A11"), },
2086 { /* Allow interrupts during suspend on Compaq Laptops*/
2087 set_apm_ints, "Compaq 12XL125",
2088 { DMI_MATCH(DMI_SYS_VENDOR, "Compaq"),
2089 DMI_MATCH(DMI_PRODUCT_NAME, "Compaq PC"),
2090 DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2091 DMI_MATCH(DMI_BIOS_VERSION, "4.06"), },
2093 { /* Allow interrupts during APM or the clock goes slow */
2094 set_apm_ints, "ASUSTeK",
2095 { DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK Computer Inc."),
2096 DMI_MATCH(DMI_PRODUCT_NAME, "L8400K series Notebook PC"), },
2098 { /* APM blows on shutdown */
2099 apm_is_horked, "ABIT KX7-333[R]",
2100 { DMI_MATCH(DMI_BOARD_VENDOR, "ABIT"),
2101 DMI_MATCH(DMI_BOARD_NAME, "VT8367-8233A (KX7-333[R])"), },
2103 { /* APM crashes */
2104 apm_is_horked, "Trigem Delhi3",
2105 { DMI_MATCH(DMI_SYS_VENDOR, "TriGem Computer, Inc"),
2106 DMI_MATCH(DMI_PRODUCT_NAME, "Delhi3"), },
2108 { /* APM crashes */
2109 apm_is_horked, "Fujitsu-Siemens",
2110 { DMI_MATCH(DMI_BIOS_VENDOR, "hoenix/FUJITSU SIEMENS"),
2111 DMI_MATCH(DMI_BIOS_VERSION, "Version1.01"), },
2113 { /* APM crashes */
2114 apm_is_horked_d850md, "Intel D850MD",
2115 { DMI_MATCH(DMI_BIOS_VENDOR, "Intel Corp."),
2116 DMI_MATCH(DMI_BIOS_VERSION, "MV85010A.86A.0016.P07.0201251536"), },
2118 { /* APM crashes */
2119 apm_is_horked, "Intel D810EMO",
2120 { DMI_MATCH(DMI_BIOS_VENDOR, "Intel Corp."),
2121 DMI_MATCH(DMI_BIOS_VERSION, "MO81010A.86A.0008.P04.0004170800"), },
2123 { /* APM crashes */
2124 apm_is_horked, "Dell XPS-Z",
2125 { DMI_MATCH(DMI_BIOS_VENDOR, "Intel Corp."),
2126 DMI_MATCH(DMI_BIOS_VERSION, "A11"),
2127 DMI_MATCH(DMI_PRODUCT_NAME, "XPS-Z"), },
2129 { /* APM crashes */
2130 apm_is_horked, "Sharp PC-PJ/AX",
2131 { DMI_MATCH(DMI_SYS_VENDOR, "SHARP"),
2132 DMI_MATCH(DMI_PRODUCT_NAME, "PC-PJ/AX"),
2133 DMI_MATCH(DMI_BIOS_VENDOR, "SystemSoft"),
2134 DMI_MATCH(DMI_BIOS_VERSION, "Version R2.08"), },
2136 { /* APM crashes */
2137 apm_is_horked, "Dell Inspiron 2500",
2138 { DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
2139 DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 2500"),
2140 DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2141 DMI_MATCH(DMI_BIOS_VERSION, "A11"), },
2143 { /* APM idle hangs */
2144 apm_likes_to_melt, "Jabil AMD",
2145 { DMI_MATCH(DMI_BIOS_VENDOR, "American Megatrends Inc."),
2146 DMI_MATCH(DMI_BIOS_VERSION, "0AASNP06"), },
2148 { /* APM idle hangs */
2149 apm_likes_to_melt, "AMI Bios",
2150 { DMI_MATCH(DMI_BIOS_VENDOR, "American Megatrends Inc."),
2151 DMI_MATCH(DMI_BIOS_VERSION, "0AASNP05"), },
2153 { /* Handle problems with APM on Sony Vaio PCG-N505X(DE) */
2154 swab_apm_power_in_minutes, "Sony VAIO",
2155 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2156 DMI_MATCH(DMI_BIOS_VERSION, "R0206H"),
2157 DMI_MATCH(DMI_BIOS_DATE, "08/23/99"), },
2159 { /* Handle problems with APM on Sony Vaio PCG-N505VX */
2160 swab_apm_power_in_minutes, "Sony VAIO",
2161 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2162 DMI_MATCH(DMI_BIOS_VERSION, "W2K06H0"),
2163 DMI_MATCH(DMI_BIOS_DATE, "02/03/00"), },
2165 { /* Handle problems with APM on Sony Vaio PCG-XG29 */
2166 swab_apm_power_in_minutes, "Sony VAIO",
2167 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2168 DMI_MATCH(DMI_BIOS_VERSION, "R0117A0"),
2169 DMI_MATCH(DMI_BIOS_DATE, "04/25/00"), },
2171 { /* Handle problems with APM on Sony Vaio PCG-Z600NE */
2172 swab_apm_power_in_minutes, "Sony VAIO",
2173 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2174 DMI_MATCH(DMI_BIOS_VERSION, "R0121Z1"),
2175 DMI_MATCH(DMI_BIOS_DATE, "05/11/00"), },
2177 { /* Handle problems with APM on Sony Vaio PCG-Z600NE */
2178 swab_apm_power_in_minutes, "Sony VAIO",
2179 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2180 DMI_MATCH(DMI_BIOS_VERSION, "WME01Z1"),
2181 DMI_MATCH(DMI_BIOS_DATE, "08/11/00"), },
2183 { /* Handle problems with APM on Sony Vaio PCG-Z600LEK(DE) */
2184 swab_apm_power_in_minutes, "Sony VAIO",
2185 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2186 DMI_MATCH(DMI_BIOS_VERSION, "R0206Z3"),
2187 DMI_MATCH(DMI_BIOS_DATE, "12/25/00"), },
2189 { /* Handle problems with APM on Sony Vaio PCG-Z505LS */
2190 swab_apm_power_in_minutes, "Sony VAIO",
2191 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2192 DMI_MATCH(DMI_BIOS_VERSION, "R0203D0"),
2193 DMI_MATCH(DMI_BIOS_DATE, "05/12/00"), },
2195 { /* Handle problems with APM on Sony Vaio PCG-Z505LS */
2196 swab_apm_power_in_minutes, "Sony VAIO",
2197 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2198 DMI_MATCH(DMI_BIOS_VERSION, "R0203Z3"),
2199 DMI_MATCH(DMI_BIOS_DATE, "08/25/00"), },
2201 { /* Handle problems with APM on Sony Vaio PCG-Z505LS (with updated BIOS) */
2202 swab_apm_power_in_minutes, "Sony VAIO",
2203 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2204 DMI_MATCH(DMI_BIOS_VERSION, "R0209Z3"),
2205 DMI_MATCH(DMI_BIOS_DATE, "05/12/01"), },
2207 { /* Handle problems with APM on Sony Vaio PCG-F104K */
2208 swab_apm_power_in_minutes, "Sony VAIO",
2209 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2210 DMI_MATCH(DMI_BIOS_VERSION, "R0204K2"),
2211 DMI_MATCH(DMI_BIOS_DATE, "08/28/00"), },
2214 { /* Handle problems with APM on Sony Vaio PCG-C1VN/C1VE */
2215 swab_apm_power_in_minutes, "Sony VAIO",
2216 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2217 DMI_MATCH(DMI_BIOS_VERSION, "R0208P1"),
2218 DMI_MATCH(DMI_BIOS_DATE, "11/09/00"), },
2220 { /* Handle problems with APM on Sony Vaio PCG-C1VE */
2221 swab_apm_power_in_minutes, "Sony VAIO",
2222 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2223 DMI_MATCH(DMI_BIOS_VERSION, "R0204P1"),
2224 DMI_MATCH(DMI_BIOS_DATE, "09/12/00"), },
2226 { /* Handle problems with APM on Sony Vaio PCG-C1VE */
2227 swab_apm_power_in_minutes, "Sony VAIO",
2228 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2229 DMI_MATCH(DMI_BIOS_VERSION, "WXPO1Z3"),
2230 DMI_MATCH(DMI_BIOS_DATE, "10/26/01"), },
2232 { /* broken PM poweroff bios */
2233 set_realmode_power_off, "Award Software v4.60 PGMA",
2234 { DMI_MATCH(DMI_BIOS_VENDOR, "Award Software International, Inc."),
2235 DMI_MATCH(DMI_BIOS_VERSION, "4.60 PGMA"),
2236 DMI_MATCH(DMI_BIOS_DATE, "134526184"), },
2239 /* Generic per vendor APM settings */
2241 { /* Allow interrupts during suspend on IBM laptops */
2242 set_apm_ints, "IBM",
2243 { DMI_MATCH(DMI_SYS_VENDOR, "IBM"), },
2250 * Just start the APM thread. We do NOT want to do APM BIOS
2251 * calls from anything but the APM thread, if for no other reason
2252 * than the fact that we don't trust the APM BIOS. This way,
2253 * most common APM BIOS problems that lead to protection errors
2254 * etc will have at least some level of being contained...
2256 * In short, if something bad happens, at least we have a choice
2257 * of just killing the apm thread..
2259 static int __init apm_init(void)
2261 struct desc_struct *gdt;
2262 int err;
2264 dmi_check_system(apm_dmi_table);
2266 if (apm_info.bios.version == 0 || paravirt_enabled() || machine_is_olpc()) {
2267 printk(KERN_INFO "apm: BIOS not found.\n");
2268 return -ENODEV;
2270 printk(KERN_INFO
2271 "apm: BIOS version %d.%d Flags 0x%02x (Driver version %s)\n",
2272 ((apm_info.bios.version >> 8) & 0xff),
2273 (apm_info.bios.version & 0xff),
2274 apm_info.bios.flags,
2275 driver_version);
2276 if ((apm_info.bios.flags & APM_32_BIT_SUPPORT) == 0) {
2277 printk(KERN_INFO "apm: no 32 bit BIOS support\n");
2278 return -ENODEV;
2281 if (allow_ints)
2282 apm_info.allow_ints = 1;
2283 if (broken_psr)
2284 apm_info.get_power_status_broken = 1;
2285 if (realmode_power_off)
2286 apm_info.realmode_power_off = 1;
2287 /* User can override, but default is to trust DMI */
2288 if (apm_disabled != -1)
2289 apm_info.disabled = apm_disabled;
2292 * Fix for the Compaq Contura 3/25c which reports BIOS version 0.1
2293 * but is reportedly a 1.0 BIOS.
2295 if (apm_info.bios.version == 0x001)
2296 apm_info.bios.version = 0x100;
2298 /* BIOS < 1.2 doesn't set cseg_16_len */
2299 if (apm_info.bios.version < 0x102)
2300 apm_info.bios.cseg_16_len = 0; /* 64k */
2302 if (debug) {
2303 printk(KERN_INFO "apm: entry %x:%x cseg16 %x dseg %x",
2304 apm_info.bios.cseg, apm_info.bios.offset,
2305 apm_info.bios.cseg_16, apm_info.bios.dseg);
2306 if (apm_info.bios.version > 0x100)
2307 printk(" cseg len %x, dseg len %x",
2308 apm_info.bios.cseg_len,
2309 apm_info.bios.dseg_len);
2310 if (apm_info.bios.version > 0x101)
2311 printk(" cseg16 len %x", apm_info.bios.cseg_16_len);
2312 printk("\n");
2315 if (apm_info.disabled) {
2316 printk(KERN_NOTICE "apm: disabled on user request.\n");
2317 return -ENODEV;
2319 if ((num_online_cpus() > 1) && !power_off && !smp) {
2320 printk(KERN_NOTICE "apm: disabled - APM is not SMP safe.\n");
2321 apm_info.disabled = 1;
2322 return -ENODEV;
2324 if (pm_flags & PM_ACPI) {
2325 printk(KERN_NOTICE "apm: overridden by ACPI.\n");
2326 apm_info.disabled = 1;
2327 return -ENODEV;
2329 pm_flags |= PM_APM;
2332 * Set up the long jump entry point to the APM BIOS, which is called
2333 * from inline assembly.
2335 apm_bios_entry.offset = apm_info.bios.offset;
2336 apm_bios_entry.segment = APM_CS;
2339 * The APM 1.1 BIOS is supposed to provide limit information that it
2340 * recognizes. Many machines do this correctly, but many others do
2341 * not restrict themselves to their claimed limit. When this happens,
2342 * they will cause a segmentation violation in the kernel at boot time.
2343 * Most BIOS's, however, will respect a 64k limit, so we use that.
2345 * Note we only set APM segments on CPU zero, since we pin the APM
2346 * code to that CPU.
2348 gdt = get_cpu_gdt_table(0);
2349 set_desc_base(&gdt[APM_CS >> 3],
2350 (unsigned long)__va((unsigned long)apm_info.bios.cseg << 4));
2351 set_desc_base(&gdt[APM_CS_16 >> 3],
2352 (unsigned long)__va((unsigned long)apm_info.bios.cseg_16 << 4));
2353 set_desc_base(&gdt[APM_DS >> 3],
2354 (unsigned long)__va((unsigned long)apm_info.bios.dseg << 4));
2356 proc_create("apm", 0, NULL, &apm_file_ops);
2358 kapmd_task = kthread_create(apm, NULL, "kapmd");
2359 if (IS_ERR(kapmd_task)) {
2360 printk(KERN_ERR "apm: disabled - Unable to start kernel "
2361 "thread.\n");
2362 err = PTR_ERR(kapmd_task);
2363 kapmd_task = NULL;
2364 remove_proc_entry("apm", NULL);
2365 return err;
2367 wake_up_process(kapmd_task);
2369 if (num_online_cpus() > 1 && !smp) {
2370 printk(KERN_NOTICE
2371 "apm: disabled - APM is not SMP safe (power off active).\n");
2372 return 0;
2376 * Note we don't actually care if the misc_device cannot be registered.
2377 * this driver can do its job without it, even if userspace can't
2378 * control it. just log the error
2380 if (misc_register(&apm_device))
2381 printk(KERN_WARNING "apm: Could not register misc device.\n");
2383 if (HZ != 100)
2384 idle_period = (idle_period * HZ) / 100;
2385 if (idle_threshold < 100) {
2386 original_pm_idle = pm_idle;
2387 pm_idle = apm_cpu_idle;
2388 set_pm_idle = 1;
2391 return 0;
2394 static void __exit apm_exit(void)
2396 int error;
2398 if (set_pm_idle) {
2399 pm_idle = original_pm_idle;
2401 * We are about to unload the current idle thread pm callback
2402 * (pm_idle), Wait for all processors to update cached/local
2403 * copies of pm_idle before proceeding.
2405 cpu_idle_wait();
2407 if (((apm_info.bios.flags & APM_BIOS_DISENGAGED) == 0)
2408 && (apm_info.connection_version > 0x0100)) {
2409 error = apm_engage_power_management(APM_DEVICE_ALL, 0);
2410 if (error)
2411 apm_error("disengage power management", error);
2413 misc_deregister(&apm_device);
2414 remove_proc_entry("apm", NULL);
2415 if (power_off)
2416 pm_power_off = NULL;
2417 if (kapmd_task) {
2418 kthread_stop(kapmd_task);
2419 kapmd_task = NULL;
2421 pm_flags &= ~PM_APM;
2424 module_init(apm_init);
2425 module_exit(apm_exit);
2427 MODULE_AUTHOR("Stephen Rothwell");
2428 MODULE_DESCRIPTION("Advanced Power Management");
2429 MODULE_LICENSE("GPL");
2430 module_param(debug, bool, 0644);
2431 MODULE_PARM_DESC(debug, "Enable debug mode");
2432 module_param(power_off, bool, 0444);
2433 MODULE_PARM_DESC(power_off, "Enable power off");
2434 module_param(bounce_interval, int, 0444);
2435 MODULE_PARM_DESC(bounce_interval,
2436 "Set the number of ticks to ignore suspend bounces");
2437 module_param(allow_ints, bool, 0444);
2438 MODULE_PARM_DESC(allow_ints, "Allow interrupts during BIOS calls");
2439 module_param(broken_psr, bool, 0444);
2440 MODULE_PARM_DESC(broken_psr, "BIOS has a broken GetPowerStatus call");
2441 module_param(realmode_power_off, bool, 0444);
2442 MODULE_PARM_DESC(realmode_power_off,
2443 "Switch to real mode before powering off");
2444 module_param(idle_threshold, int, 0444);
2445 MODULE_PARM_DESC(idle_threshold,
2446 "System idle percentage above which to make APM BIOS idle calls");
2447 module_param(idle_period, int, 0444);
2448 MODULE_PARM_DESC(idle_period,
2449 "Period (in sec/100) over which to caculate the idle percentage");
2450 module_param(smp, bool, 0444);
2451 MODULE_PARM_DESC(smp,
2452 "Set this to enable APM use on an SMP platform. Use with caution on older systems");
2453 MODULE_ALIAS_MISCDEV(APM_MINOR_DEV);