x86: pat.c final cleanup of loop body in reserve_memtype
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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@suse.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@redhat.com>).
164 * 1.14ac: If the BIOS says "I slowed the CPU down" then don't spin
165 * calling it - instead idle. (Alan Cox <alan@redhat.com>)
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 via anonymous ftp from
193 * ftp://ftp.intel.com/pub/IAL/software_specs/apmv11.doc. It is also
194 * available from Microsoft by calling 206.882.8080.]
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/pm_legacy.h>
222 #include <linux/capability.h>
223 #include <linux/device.h>
224 #include <linux/kernel.h>
225 #include <linux/freezer.h>
226 #include <linux/smp.h>
227 #include <linux/dmi.h>
228 #include <linux/suspend.h>
229 #include <linux/kthread.h>
230 #include <linux/jiffies.h>
232 #include <asm/system.h>
233 #include <asm/uaccess.h>
234 #include <asm/desc.h>
235 #include <asm/i8253.h>
236 #include <asm/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 "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 #ifdef CONFIG_APM_REAL_MODE_POWER_OFF
394 static int realmode_power_off = 1;
395 #else
396 static int realmode_power_off;
397 #endif
398 #ifdef CONFIG_APM_ALLOW_INTS
399 static int allow_ints = 1;
400 #else
401 static int allow_ints;
402 #endif
403 static int broken_psr;
405 static DECLARE_WAIT_QUEUE_HEAD(apm_waitqueue);
406 static DECLARE_WAIT_QUEUE_HEAD(apm_suspend_waitqueue);
407 static struct apm_user *user_list;
408 static DEFINE_SPINLOCK(user_list_lock);
409 static const struct desc_struct bad_bios_desc = { { { 0, 0x00409200 } } };
411 static const char driver_version[] = "1.16ac"; /* no spaces */
413 static struct task_struct *kapmd_task;
416 * APM event names taken from the APM 1.2 specification. These are
417 * the message codes that the BIOS uses to tell us about events
419 static const char * const apm_event_name[] = {
420 "system standby",
421 "system suspend",
422 "normal resume",
423 "critical resume",
424 "low battery",
425 "power status change",
426 "update time",
427 "critical suspend",
428 "user standby",
429 "user suspend",
430 "system standby resume",
431 "capabilities change"
433 #define NR_APM_EVENT_NAME ARRAY_SIZE(apm_event_name)
435 typedef struct lookup_t {
436 int key;
437 char *msg;
438 } lookup_t;
441 * The BIOS returns a set of standard error codes in AX when the
442 * carry flag is set.
445 static const lookup_t error_table[] = {
446 /* N/A { APM_SUCCESS, "Operation succeeded" }, */
447 { APM_DISABLED, "Power management disabled" },
448 { APM_CONNECTED, "Real mode interface already connected" },
449 { APM_NOT_CONNECTED, "Interface not connected" },
450 { APM_16_CONNECTED, "16 bit interface already connected" },
451 /* N/A { APM_16_UNSUPPORTED, "16 bit interface not supported" }, */
452 { APM_32_CONNECTED, "32 bit interface already connected" },
453 { APM_32_UNSUPPORTED, "32 bit interface not supported" },
454 { APM_BAD_DEVICE, "Unrecognized device ID" },
455 { APM_BAD_PARAM, "Parameter out of range" },
456 { APM_NOT_ENGAGED, "Interface not engaged" },
457 { APM_BAD_FUNCTION, "Function not supported" },
458 { APM_RESUME_DISABLED, "Resume timer disabled" },
459 { APM_BAD_STATE, "Unable to enter requested state" },
460 /* N/A { APM_NO_EVENTS, "No events pending" }, */
461 { APM_NO_ERROR, "BIOS did not set a return code" },
462 { APM_NOT_PRESENT, "No APM present" }
464 #define ERROR_COUNT ARRAY_SIZE(error_table)
467 * apm_error - display an APM error
468 * @str: information string
469 * @err: APM BIOS return code
471 * Write a meaningful log entry to the kernel log in the event of
472 * an APM error.
475 static void apm_error(char *str, int err)
477 int i;
479 for (i = 0; i < ERROR_COUNT; i++)
480 if (error_table[i].key == err)
481 break;
482 if (i < ERROR_COUNT)
483 printk(KERN_NOTICE "apm: %s: %s\n", str, error_table[i].msg);
484 else
485 printk(KERN_NOTICE "apm: %s: unknown error code %#2.2x\n",
486 str, err);
490 * Lock APM functionality to physical CPU 0
493 #ifdef CONFIG_SMP
495 static cpumask_t apm_save_cpus(void)
497 cpumask_t x = current->cpus_allowed;
498 /* Some bioses don't like being called from CPU != 0 */
499 set_cpus_allowed(current, cpumask_of_cpu(0));
500 BUG_ON(smp_processor_id() != 0);
501 return x;
504 static inline void apm_restore_cpus(cpumask_t mask)
506 set_cpus_allowed(current, mask);
509 #else
512 * No CPU lockdown needed on a uniprocessor
515 #define apm_save_cpus() (current->cpus_allowed)
516 #define apm_restore_cpus(x) (void)(x)
518 #endif
521 * These are the actual BIOS calls. Depending on APM_ZERO_SEGS and
522 * apm_info.allow_ints, we are being really paranoid here! Not only
523 * are interrupts disabled, but all the segment registers (except SS)
524 * are saved and zeroed this means that if the BIOS tries to reference
525 * any data without explicitly loading the segment registers, the kernel
526 * will fault immediately rather than have some unforeseen circumstances
527 * for the rest of the kernel. And it will be very obvious! :-) Doing
528 * this depends on CS referring to the same physical memory as DS so that
529 * DS can be zeroed before the call. Unfortunately, we can't do anything
530 * about the stack segment/pointer. Also, we tell the compiler that
531 * everything could change.
533 * Also, we KNOW that for the non error case of apm_bios_call, there
534 * is no useful data returned in the low order 8 bits of eax.
537 static inline unsigned long __apm_irq_save(void)
539 unsigned long flags;
540 local_save_flags(flags);
541 if (apm_info.allow_ints) {
542 if (irqs_disabled_flags(flags))
543 local_irq_enable();
544 } else
545 local_irq_disable();
547 return flags;
550 #define apm_irq_save(flags) \
551 do { flags = __apm_irq_save(); } while (0)
553 static inline void apm_irq_restore(unsigned long flags)
555 if (irqs_disabled_flags(flags))
556 local_irq_disable();
557 else if (irqs_disabled())
558 local_irq_enable();
561 #ifdef APM_ZERO_SEGS
562 # define APM_DECL_SEGS \
563 unsigned int saved_fs; unsigned int saved_gs;
564 # define APM_DO_SAVE_SEGS \
565 savesegment(fs, saved_fs); savesegment(gs, saved_gs)
566 # define APM_DO_RESTORE_SEGS \
567 loadsegment(fs, saved_fs); loadsegment(gs, saved_gs)
568 #else
569 # define APM_DECL_SEGS
570 # define APM_DO_SAVE_SEGS
571 # define APM_DO_RESTORE_SEGS
572 #endif
575 * apm_bios_call - Make an APM BIOS 32bit call
576 * @func: APM function to execute
577 * @ebx_in: EBX register for call entry
578 * @ecx_in: ECX register for call entry
579 * @eax: EAX register return
580 * @ebx: EBX register return
581 * @ecx: ECX register return
582 * @edx: EDX register return
583 * @esi: ESI register return
585 * Make an APM call using the 32bit protected mode interface. The
586 * caller is responsible for knowing if APM BIOS is configured and
587 * enabled. This call can disable interrupts for a long period of
588 * time on some laptops. The return value is in AH and the carry
589 * flag is loaded into AL. If there is an error, then the error
590 * code is returned in AH (bits 8-15 of eax) and this function
591 * returns non-zero.
594 static u8 apm_bios_call(u32 func, u32 ebx_in, u32 ecx_in,
595 u32 *eax, u32 *ebx, u32 *ecx, u32 *edx, u32 *esi)
597 APM_DECL_SEGS
598 unsigned long flags;
599 cpumask_t cpus;
600 int cpu;
601 struct desc_struct save_desc_40;
602 struct desc_struct *gdt;
604 cpus = apm_save_cpus();
606 cpu = get_cpu();
607 gdt = get_cpu_gdt_table(cpu);
608 save_desc_40 = gdt[0x40 / 8];
609 gdt[0x40 / 8] = bad_bios_desc;
611 apm_irq_save(flags);
612 APM_DO_SAVE_SEGS;
613 apm_bios_call_asm(func, ebx_in, ecx_in, eax, ebx, ecx, edx, esi);
614 APM_DO_RESTORE_SEGS;
615 apm_irq_restore(flags);
616 gdt[0x40 / 8] = save_desc_40;
617 put_cpu();
618 apm_restore_cpus(cpus);
620 return *eax & 0xff;
624 * apm_bios_call_simple - make a simple APM BIOS 32bit call
625 * @func: APM function to invoke
626 * @ebx_in: EBX register value for BIOS call
627 * @ecx_in: ECX register value for BIOS call
628 * @eax: EAX register on return from the BIOS call
630 * Make a BIOS call that returns one value only, or just status.
631 * If there is an error, then the error code is returned in AH
632 * (bits 8-15 of eax) and this function returns non-zero. This is
633 * used for simpler BIOS operations. This call may hold interrupts
634 * off for a long time on some laptops.
637 static u8 apm_bios_call_simple(u32 func, u32 ebx_in, u32 ecx_in, u32 *eax)
639 u8 error;
640 APM_DECL_SEGS
641 unsigned long flags;
642 cpumask_t cpus;
643 int cpu;
644 struct desc_struct save_desc_40;
645 struct desc_struct *gdt;
647 cpus = apm_save_cpus();
649 cpu = get_cpu();
650 gdt = get_cpu_gdt_table(cpu);
651 save_desc_40 = gdt[0x40 / 8];
652 gdt[0x40 / 8] = bad_bios_desc;
654 apm_irq_save(flags);
655 APM_DO_SAVE_SEGS;
656 error = apm_bios_call_simple_asm(func, ebx_in, ecx_in, eax);
657 APM_DO_RESTORE_SEGS;
658 apm_irq_restore(flags);
659 gdt[0x40 / 8] = save_desc_40;
660 put_cpu();
661 apm_restore_cpus(cpus);
662 return error;
666 * apm_driver_version - APM driver version
667 * @val: loaded with the APM version on return
669 * Retrieve the APM version supported by the BIOS. This is only
670 * supported for APM 1.1 or higher. An error indicates APM 1.0 is
671 * probably present.
673 * On entry val should point to a value indicating the APM driver
674 * version with the high byte being the major and the low byte the
675 * minor number both in BCD
677 * On return it will hold the BIOS revision supported in the
678 * same format.
681 static int apm_driver_version(u_short *val)
683 u32 eax;
685 if (apm_bios_call_simple(APM_FUNC_VERSION, 0, *val, &eax))
686 return (eax >> 8) & 0xff;
687 *val = eax;
688 return APM_SUCCESS;
692 * apm_get_event - get an APM event from the BIOS
693 * @event: pointer to the event
694 * @info: point to the event information
696 * The APM BIOS provides a polled information for event
697 * reporting. The BIOS expects to be polled at least every second
698 * when events are pending. When a message is found the caller should
699 * poll until no more messages are present. However, this causes
700 * problems on some laptops where a suspend event notification is
701 * not cleared until it is acknowledged.
703 * Additional information is returned in the info pointer, providing
704 * that APM 1.2 is in use. If no messges are pending the value 0x80
705 * is returned (No power management events pending).
708 static int apm_get_event(apm_event_t *event, apm_eventinfo_t *info)
710 u32 eax;
711 u32 ebx;
712 u32 ecx;
713 u32 dummy;
715 if (apm_bios_call(APM_FUNC_GET_EVENT, 0, 0, &eax, &ebx, &ecx,
716 &dummy, &dummy))
717 return (eax >> 8) & 0xff;
718 *event = ebx;
719 if (apm_info.connection_version < 0x0102)
720 *info = ~0; /* indicate info not valid */
721 else
722 *info = ecx;
723 return APM_SUCCESS;
727 * set_power_state - set the power management state
728 * @what: which items to transition
729 * @state: state to transition to
731 * Request an APM change of state for one or more system devices. The
732 * processor state must be transitioned last of all. what holds the
733 * class of device in the upper byte and the device number (0xFF for
734 * all) for the object to be transitioned.
736 * The state holds the state to transition to, which may in fact
737 * be an acceptance of a BIOS requested state change.
740 static int set_power_state(u_short what, u_short state)
742 u32 eax;
744 if (apm_bios_call_simple(APM_FUNC_SET_STATE, what, state, &eax))
745 return (eax >> 8) & 0xff;
746 return APM_SUCCESS;
750 * set_system_power_state - set system wide power state
751 * @state: which state to enter
753 * Transition the entire system into a new APM power state.
756 static int set_system_power_state(u_short state)
758 return set_power_state(APM_DEVICE_ALL, state);
762 * apm_do_idle - perform power saving
764 * This function notifies the BIOS that the processor is (in the view
765 * of the OS) idle. It returns -1 in the event that the BIOS refuses
766 * to handle the idle request. On a success the function returns 1
767 * if the BIOS did clock slowing or 0 otherwise.
770 static int apm_do_idle(void)
772 u32 eax;
773 u8 ret = 0;
774 int idled = 0;
775 int polling;
777 polling = !!(current_thread_info()->status & TS_POLLING);
778 if (polling) {
779 current_thread_info()->status &= ~TS_POLLING;
781 * TS_POLLING-cleared state must be visible before we
782 * test NEED_RESCHED:
784 smp_mb();
786 if (!need_resched()) {
787 idled = 1;
788 ret = apm_bios_call_simple(APM_FUNC_IDLE, 0, 0, &eax);
790 if (polling)
791 current_thread_info()->status |= TS_POLLING;
793 if (!idled)
794 return 0;
796 if (ret) {
797 static unsigned long t;
799 /* This always fails on some SMP boards running UP kernels.
800 * Only report the failure the first 5 times.
802 if (++t < 5) {
803 printk(KERN_DEBUG "apm_do_idle failed (%d)\n",
804 (eax >> 8) & 0xff);
805 t = jiffies;
807 return -1;
809 clock_slowed = (apm_info.bios.flags & APM_IDLE_SLOWS_CLOCK) != 0;
810 return clock_slowed;
814 * apm_do_busy - inform the BIOS the CPU is busy
816 * Request that the BIOS brings the CPU back to full performance.
819 static void apm_do_busy(void)
821 u32 dummy;
823 if (clock_slowed || ALWAYS_CALL_BUSY) {
824 (void)apm_bios_call_simple(APM_FUNC_BUSY, 0, 0, &dummy);
825 clock_slowed = 0;
830 * If no process has really been interested in
831 * the CPU for some time, we want to call BIOS
832 * power management - we probably want
833 * to conserve power.
835 #define IDLE_CALC_LIMIT (HZ * 100)
836 #define IDLE_LEAKY_MAX 16
838 static void (*original_pm_idle)(void) __read_mostly;
841 * apm_cpu_idle - cpu idling for APM capable Linux
843 * This is the idling function the kernel executes when APM is available. It
844 * tries to do BIOS powermanagement based on the average system idle time.
845 * Furthermore it calls the system default idle routine.
848 static void apm_cpu_idle(void)
850 static int use_apm_idle; /* = 0 */
851 static unsigned int last_jiffies; /* = 0 */
852 static unsigned int last_stime; /* = 0 */
854 int apm_idle_done = 0;
855 unsigned int jiffies_since_last_check = jiffies - last_jiffies;
856 unsigned int bucket;
858 recalc:
859 if (jiffies_since_last_check > IDLE_CALC_LIMIT) {
860 use_apm_idle = 0;
861 last_jiffies = jiffies;
862 last_stime = current->stime;
863 } else if (jiffies_since_last_check > idle_period) {
864 unsigned int idle_percentage;
866 idle_percentage = current->stime - last_stime;
867 idle_percentage *= 100;
868 idle_percentage /= jiffies_since_last_check;
869 use_apm_idle = (idle_percentage > idle_threshold);
870 if (apm_info.forbid_idle)
871 use_apm_idle = 0;
872 last_jiffies = jiffies;
873 last_stime = current->stime;
876 bucket = IDLE_LEAKY_MAX;
878 while (!need_resched()) {
879 if (use_apm_idle) {
880 unsigned int t;
882 t = jiffies;
883 switch (apm_do_idle()) {
884 case 0:
885 apm_idle_done = 1;
886 if (t != jiffies) {
887 if (bucket) {
888 bucket = IDLE_LEAKY_MAX;
889 continue;
891 } else if (bucket) {
892 bucket--;
893 continue;
895 break;
896 case 1:
897 apm_idle_done = 1;
898 break;
899 default: /* BIOS refused */
900 break;
903 if (original_pm_idle)
904 original_pm_idle();
905 else
906 default_idle();
907 local_irq_disable();
908 jiffies_since_last_check = jiffies - last_jiffies;
909 if (jiffies_since_last_check > idle_period)
910 goto recalc;
913 if (apm_idle_done)
914 apm_do_busy();
916 local_irq_enable();
920 * apm_power_off - ask the BIOS to power off
922 * Handle the power off sequence. This is the one piece of code we
923 * will execute even on SMP machines. In order to deal with BIOS
924 * bugs we support real mode APM BIOS power off calls. We also make
925 * the SMP call on CPU0 as some systems will only honour this call
926 * on their first cpu.
929 static void apm_power_off(void)
931 unsigned char po_bios_call[] = {
932 0xb8, 0x00, 0x10, /* movw $0x1000,ax */
933 0x8e, 0xd0, /* movw ax,ss */
934 0xbc, 0x00, 0xf0, /* movw $0xf000,sp */
935 0xb8, 0x07, 0x53, /* movw $0x5307,ax */
936 0xbb, 0x01, 0x00, /* movw $0x0001,bx */
937 0xb9, 0x03, 0x00, /* movw $0x0003,cx */
938 0xcd, 0x15 /* int $0x15 */
941 /* Some bioses don't like being called from CPU != 0 */
942 if (apm_info.realmode_power_off) {
943 (void)apm_save_cpus();
944 machine_real_restart(po_bios_call, sizeof(po_bios_call));
945 } else {
946 (void)set_system_power_state(APM_STATE_OFF);
950 #ifdef CONFIG_APM_DO_ENABLE
953 * apm_enable_power_management - enable BIOS APM power management
954 * @enable: enable yes/no
956 * Enable or disable the APM BIOS power services.
959 static int apm_enable_power_management(int enable)
961 u32 eax;
963 if ((enable == 0) && (apm_info.bios.flags & APM_BIOS_DISENGAGED))
964 return APM_NOT_ENGAGED;
965 if (apm_bios_call_simple(APM_FUNC_ENABLE_PM, APM_DEVICE_BALL,
966 enable, &eax))
967 return (eax >> 8) & 0xff;
968 if (enable)
969 apm_info.bios.flags &= ~APM_BIOS_DISABLED;
970 else
971 apm_info.bios.flags |= APM_BIOS_DISABLED;
972 return APM_SUCCESS;
974 #endif
977 * apm_get_power_status - get current power state
978 * @status: returned status
979 * @bat: battery info
980 * @life: estimated life
982 * Obtain the current power status from the APM BIOS. We return a
983 * status which gives the rough battery status, and current power
984 * source. The bat value returned give an estimate as a percentage
985 * of life and a status value for the battery. The estimated life
986 * if reported is a lifetime in secodnds/minutes at current powwer
987 * consumption.
990 static int apm_get_power_status(u_short *status, u_short *bat, u_short *life)
992 u32 eax;
993 u32 ebx;
994 u32 ecx;
995 u32 edx;
996 u32 dummy;
998 if (apm_info.get_power_status_broken)
999 return APM_32_UNSUPPORTED;
1000 if (apm_bios_call(APM_FUNC_GET_STATUS, APM_DEVICE_ALL, 0,
1001 &eax, &ebx, &ecx, &edx, &dummy))
1002 return (eax >> 8) & 0xff;
1003 *status = ebx;
1004 *bat = ecx;
1005 if (apm_info.get_power_status_swabinminutes) {
1006 *life = swab16((u16)edx);
1007 *life |= 0x8000;
1008 } else
1009 *life = edx;
1010 return APM_SUCCESS;
1013 #if 0
1014 static int apm_get_battery_status(u_short which, u_short *status,
1015 u_short *bat, u_short *life, u_short *nbat)
1017 u32 eax;
1018 u32 ebx;
1019 u32 ecx;
1020 u32 edx;
1021 u32 esi;
1023 if (apm_info.connection_version < 0x0102) {
1024 /* pretend we only have one battery. */
1025 if (which != 1)
1026 return APM_BAD_DEVICE;
1027 *nbat = 1;
1028 return apm_get_power_status(status, bat, life);
1031 if (apm_bios_call(APM_FUNC_GET_STATUS, (0x8000 | (which)), 0, &eax,
1032 &ebx, &ecx, &edx, &esi))
1033 return (eax >> 8) & 0xff;
1034 *status = ebx;
1035 *bat = ecx;
1036 *life = edx;
1037 *nbat = esi;
1038 return APM_SUCCESS;
1040 #endif
1043 * apm_engage_power_management - enable PM on a device
1044 * @device: identity of device
1045 * @enable: on/off
1047 * Activate or deactive power management on either a specific device
1048 * or the entire system (%APM_DEVICE_ALL).
1051 static int apm_engage_power_management(u_short device, int enable)
1053 u32 eax;
1055 if ((enable == 0) && (device == APM_DEVICE_ALL)
1056 && (apm_info.bios.flags & APM_BIOS_DISABLED))
1057 return APM_DISABLED;
1058 if (apm_bios_call_simple(APM_FUNC_ENGAGE_PM, device, enable, &eax))
1059 return (eax >> 8) & 0xff;
1060 if (device == APM_DEVICE_ALL) {
1061 if (enable)
1062 apm_info.bios.flags &= ~APM_BIOS_DISENGAGED;
1063 else
1064 apm_info.bios.flags |= APM_BIOS_DISENGAGED;
1066 return APM_SUCCESS;
1069 #if defined(CONFIG_APM_DISPLAY_BLANK) && defined(CONFIG_VT)
1072 * apm_console_blank - blank the display
1073 * @blank: on/off
1075 * Attempt to blank the console, firstly by blanking just video device
1076 * zero, and if that fails (some BIOSes don't support it) then it blanks
1077 * all video devices. Typically the BIOS will do laptop backlight and
1078 * monitor powerdown for us.
1081 static int apm_console_blank(int blank)
1083 int error = APM_NOT_ENGAGED; /* silence gcc */
1084 int i;
1085 u_short state;
1086 static const u_short dev[3] = { 0x100, 0x1FF, 0x101 };
1088 state = blank ? APM_STATE_STANDBY : APM_STATE_READY;
1090 for (i = 0; i < ARRAY_SIZE(dev); i++) {
1091 error = set_power_state(dev[i], state);
1093 if ((error == APM_SUCCESS) || (error == APM_NO_ERROR))
1094 return 1;
1096 if (error == APM_NOT_ENGAGED)
1097 break;
1100 if (error == APM_NOT_ENGAGED) {
1101 static int tried;
1102 int eng_error;
1103 if (tried++ == 0) {
1104 eng_error = apm_engage_power_management(APM_DEVICE_ALL, 1);
1105 if (eng_error) {
1106 apm_error("set display", error);
1107 apm_error("engage interface", eng_error);
1108 return 0;
1109 } else
1110 return apm_console_blank(blank);
1113 apm_error("set display", error);
1114 return 0;
1116 #endif
1118 static int queue_empty(struct apm_user *as)
1120 return as->event_head == as->event_tail;
1123 static apm_event_t get_queued_event(struct apm_user *as)
1125 if (++as->event_tail >= APM_MAX_EVENTS)
1126 as->event_tail = 0;
1127 return as->events[as->event_tail];
1130 static void queue_event(apm_event_t event, struct apm_user *sender)
1132 struct apm_user *as;
1134 spin_lock(&user_list_lock);
1135 if (user_list == NULL)
1136 goto out;
1137 for (as = user_list; as != NULL; as = as->next) {
1138 if ((as == sender) || (!as->reader))
1139 continue;
1140 if (++as->event_head >= APM_MAX_EVENTS)
1141 as->event_head = 0;
1143 if (as->event_head == as->event_tail) {
1144 static int notified;
1146 if (notified++ == 0)
1147 printk(KERN_ERR "apm: an event queue overflowed\n");
1148 if (++as->event_tail >= APM_MAX_EVENTS)
1149 as->event_tail = 0;
1151 as->events[as->event_head] = event;
1152 if ((!as->suser) || (!as->writer))
1153 continue;
1154 switch (event) {
1155 case APM_SYS_SUSPEND:
1156 case APM_USER_SUSPEND:
1157 as->suspends_pending++;
1158 suspends_pending++;
1159 break;
1161 case APM_SYS_STANDBY:
1162 case APM_USER_STANDBY:
1163 as->standbys_pending++;
1164 standbys_pending++;
1165 break;
1168 wake_up_interruptible(&apm_waitqueue);
1169 out:
1170 spin_unlock(&user_list_lock);
1173 static void reinit_timer(void)
1175 #ifdef INIT_TIMER_AFTER_SUSPEND
1176 unsigned long flags;
1178 spin_lock_irqsave(&i8253_lock, flags);
1179 /* set the clock to HZ */
1180 outb_pit(0x34, PIT_MODE); /* binary, mode 2, LSB/MSB, ch 0 */
1181 udelay(10);
1182 outb_pit(LATCH & 0xff, PIT_CH0); /* LSB */
1183 udelay(10);
1184 outb_pit(LATCH >> 8, PIT_CH0); /* MSB */
1185 udelay(10);
1186 spin_unlock_irqrestore(&i8253_lock, flags);
1187 #endif
1190 static int suspend(int vetoable)
1192 int err;
1193 struct apm_user *as;
1195 device_suspend(PMSG_SUSPEND);
1196 local_irq_disable();
1197 device_power_down(PMSG_SUSPEND);
1199 local_irq_enable();
1201 save_processor_state();
1202 err = set_system_power_state(APM_STATE_SUSPEND);
1203 ignore_normal_resume = 1;
1204 restore_processor_state();
1206 local_irq_disable();
1207 reinit_timer();
1209 if (err == APM_NO_ERROR)
1210 err = APM_SUCCESS;
1211 if (err != APM_SUCCESS)
1212 apm_error("suspend", err);
1213 err = (err == APM_SUCCESS) ? 0 : -EIO;
1214 device_power_up();
1215 local_irq_enable();
1216 device_resume();
1217 queue_event(APM_NORMAL_RESUME, NULL);
1218 spin_lock(&user_list_lock);
1219 for (as = user_list; as != NULL; as = as->next) {
1220 as->suspend_wait = 0;
1221 as->suspend_result = err;
1223 spin_unlock(&user_list_lock);
1224 wake_up_interruptible(&apm_suspend_waitqueue);
1225 return err;
1228 static void standby(void)
1230 int err;
1232 local_irq_disable();
1233 device_power_down(PMSG_SUSPEND);
1234 local_irq_enable();
1236 err = set_system_power_state(APM_STATE_STANDBY);
1237 if ((err != APM_SUCCESS) && (err != APM_NO_ERROR))
1238 apm_error("standby", err);
1240 local_irq_disable();
1241 device_power_up();
1242 local_irq_enable();
1245 static apm_event_t get_event(void)
1247 int error;
1248 apm_event_t event = APM_NO_EVENTS; /* silence gcc */
1249 apm_eventinfo_t info;
1251 static int notified;
1253 /* we don't use the eventinfo */
1254 error = apm_get_event(&event, &info);
1255 if (error == APM_SUCCESS)
1256 return event;
1258 if ((error != APM_NO_EVENTS) && (notified++ == 0))
1259 apm_error("get_event", error);
1261 return 0;
1264 static void check_events(void)
1266 apm_event_t event;
1267 static unsigned long last_resume;
1268 static int ignore_bounce;
1270 while ((event = get_event()) != 0) {
1271 if (debug) {
1272 if (event <= NR_APM_EVENT_NAME)
1273 printk(KERN_DEBUG "apm: received %s notify\n",
1274 apm_event_name[event - 1]);
1275 else
1276 printk(KERN_DEBUG "apm: received unknown "
1277 "event 0x%02x\n", event);
1279 if (ignore_bounce
1280 && (time_after(jiffies, last_resume + bounce_interval)))
1281 ignore_bounce = 0;
1283 switch (event) {
1284 case APM_SYS_STANDBY:
1285 case APM_USER_STANDBY:
1286 queue_event(event, NULL);
1287 if (standbys_pending <= 0)
1288 standby();
1289 break;
1291 case APM_USER_SUSPEND:
1292 #ifdef CONFIG_APM_IGNORE_USER_SUSPEND
1293 if (apm_info.connection_version > 0x100)
1294 set_system_power_state(APM_STATE_REJECT);
1295 break;
1296 #endif
1297 case APM_SYS_SUSPEND:
1298 if (ignore_bounce) {
1299 if (apm_info.connection_version > 0x100)
1300 set_system_power_state(APM_STATE_REJECT);
1301 break;
1304 * If we are already processing a SUSPEND,
1305 * then further SUSPEND events from the BIOS
1306 * will be ignored. We also return here to
1307 * cope with the fact that the Thinkpads keep
1308 * sending a SUSPEND event until something else
1309 * happens!
1311 if (ignore_sys_suspend)
1312 return;
1313 ignore_sys_suspend = 1;
1314 queue_event(event, NULL);
1315 if (suspends_pending <= 0)
1316 (void) suspend(1);
1317 break;
1319 case APM_NORMAL_RESUME:
1320 case APM_CRITICAL_RESUME:
1321 case APM_STANDBY_RESUME:
1322 ignore_sys_suspend = 0;
1323 last_resume = jiffies;
1324 ignore_bounce = 1;
1325 if ((event != APM_NORMAL_RESUME)
1326 || (ignore_normal_resume == 0)) {
1327 device_resume();
1328 queue_event(event, NULL);
1330 ignore_normal_resume = 0;
1331 break;
1333 case APM_CAPABILITY_CHANGE:
1334 case APM_LOW_BATTERY:
1335 case APM_POWER_STATUS_CHANGE:
1336 queue_event(event, NULL);
1337 /* If needed, notify drivers here */
1338 break;
1340 case APM_UPDATE_TIME:
1341 break;
1343 case APM_CRITICAL_SUSPEND:
1345 * We are not allowed to reject a critical suspend.
1347 (void)suspend(0);
1348 break;
1353 static void apm_event_handler(void)
1355 static int pending_count = 4;
1356 int err;
1358 if ((standbys_pending > 0) || (suspends_pending > 0)) {
1359 if ((apm_info.connection_version > 0x100) &&
1360 (pending_count-- <= 0)) {
1361 pending_count = 4;
1362 if (debug)
1363 printk(KERN_DEBUG "apm: setting state busy\n");
1364 err = set_system_power_state(APM_STATE_BUSY);
1365 if (err)
1366 apm_error("busy", err);
1368 } else
1369 pending_count = 4;
1370 check_events();
1374 * This is the APM thread main loop.
1377 static void apm_mainloop(void)
1379 DECLARE_WAITQUEUE(wait, current);
1381 add_wait_queue(&apm_waitqueue, &wait);
1382 set_current_state(TASK_INTERRUPTIBLE);
1383 for (;;) {
1384 schedule_timeout(APM_CHECK_TIMEOUT);
1385 if (kthread_should_stop())
1386 break;
1388 * Ok, check all events, check for idle (and mark us sleeping
1389 * so as not to count towards the load average)..
1391 set_current_state(TASK_INTERRUPTIBLE);
1392 apm_event_handler();
1394 remove_wait_queue(&apm_waitqueue, &wait);
1397 static int check_apm_user(struct apm_user *as, const char *func)
1399 if ((as == NULL) || (as->magic != APM_BIOS_MAGIC)) {
1400 printk(KERN_ERR "apm: %s passed bad filp\n", func);
1401 return 1;
1403 return 0;
1406 static ssize_t do_read(struct file *fp, char __user *buf, size_t count, loff_t *ppos)
1408 struct apm_user *as;
1409 int i;
1410 apm_event_t event;
1412 as = fp->private_data;
1413 if (check_apm_user(as, "read"))
1414 return -EIO;
1415 if ((int)count < sizeof(apm_event_t))
1416 return -EINVAL;
1417 if ((queue_empty(as)) && (fp->f_flags & O_NONBLOCK))
1418 return -EAGAIN;
1419 wait_event_interruptible(apm_waitqueue, !queue_empty(as));
1420 i = count;
1421 while ((i >= sizeof(event)) && !queue_empty(as)) {
1422 event = get_queued_event(as);
1423 if (copy_to_user(buf, &event, sizeof(event))) {
1424 if (i < count)
1425 break;
1426 return -EFAULT;
1428 switch (event) {
1429 case APM_SYS_SUSPEND:
1430 case APM_USER_SUSPEND:
1431 as->suspends_read++;
1432 break;
1434 case APM_SYS_STANDBY:
1435 case APM_USER_STANDBY:
1436 as->standbys_read++;
1437 break;
1439 buf += sizeof(event);
1440 i -= sizeof(event);
1442 if (i < count)
1443 return count - i;
1444 if (signal_pending(current))
1445 return -ERESTARTSYS;
1446 return 0;
1449 static unsigned int do_poll(struct file *fp, poll_table *wait)
1451 struct apm_user *as;
1453 as = fp->private_data;
1454 if (check_apm_user(as, "poll"))
1455 return 0;
1456 poll_wait(fp, &apm_waitqueue, wait);
1457 if (!queue_empty(as))
1458 return POLLIN | POLLRDNORM;
1459 return 0;
1462 static int do_ioctl(struct inode *inode, struct file *filp,
1463 u_int cmd, u_long arg)
1465 struct apm_user *as;
1467 as = filp->private_data;
1468 if (check_apm_user(as, "ioctl"))
1469 return -EIO;
1470 if ((!as->suser) || (!as->writer))
1471 return -EPERM;
1472 switch (cmd) {
1473 case APM_IOC_STANDBY:
1474 if (as->standbys_read > 0) {
1475 as->standbys_read--;
1476 as->standbys_pending--;
1477 standbys_pending--;
1478 } else
1479 queue_event(APM_USER_STANDBY, as);
1480 if (standbys_pending <= 0)
1481 standby();
1482 break;
1483 case APM_IOC_SUSPEND:
1484 if (as->suspends_read > 0) {
1485 as->suspends_read--;
1486 as->suspends_pending--;
1487 suspends_pending--;
1488 } else
1489 queue_event(APM_USER_SUSPEND, as);
1490 if (suspends_pending <= 0) {
1491 return suspend(1);
1492 } else {
1493 as->suspend_wait = 1;
1494 wait_event_interruptible(apm_suspend_waitqueue,
1495 as->suspend_wait == 0);
1496 return as->suspend_result;
1498 break;
1499 default:
1500 return -EINVAL;
1502 return 0;
1505 static int do_release(struct inode *inode, struct file *filp)
1507 struct apm_user *as;
1509 as = filp->private_data;
1510 if (check_apm_user(as, "release"))
1511 return 0;
1512 filp->private_data = NULL;
1513 if (as->standbys_pending > 0) {
1514 standbys_pending -= as->standbys_pending;
1515 if (standbys_pending <= 0)
1516 standby();
1518 if (as->suspends_pending > 0) {
1519 suspends_pending -= as->suspends_pending;
1520 if (suspends_pending <= 0)
1521 (void) suspend(1);
1523 spin_lock(&user_list_lock);
1524 if (user_list == as)
1525 user_list = as->next;
1526 else {
1527 struct apm_user *as1;
1529 for (as1 = user_list;
1530 (as1 != NULL) && (as1->next != as);
1531 as1 = as1->next)
1533 if (as1 == NULL)
1534 printk(KERN_ERR "apm: filp not in user list\n");
1535 else
1536 as1->next = as->next;
1538 spin_unlock(&user_list_lock);
1539 kfree(as);
1540 return 0;
1543 static int do_open(struct inode *inode, struct file *filp)
1545 struct apm_user *as;
1547 as = kmalloc(sizeof(*as), GFP_KERNEL);
1548 if (as == NULL) {
1549 printk(KERN_ERR "apm: cannot allocate struct of size %d bytes\n",
1550 sizeof(*as));
1551 return -ENOMEM;
1553 as->magic = APM_BIOS_MAGIC;
1554 as->event_tail = as->event_head = 0;
1555 as->suspends_pending = as->standbys_pending = 0;
1556 as->suspends_read = as->standbys_read = 0;
1558 * XXX - this is a tiny bit broken, when we consider BSD
1559 * process accounting. If the device is opened by root, we
1560 * instantly flag that we used superuser privs. Who knows,
1561 * we might close the device immediately without doing a
1562 * privileged operation -- cevans
1564 as->suser = capable(CAP_SYS_ADMIN);
1565 as->writer = (filp->f_mode & FMODE_WRITE) == FMODE_WRITE;
1566 as->reader = (filp->f_mode & FMODE_READ) == FMODE_READ;
1567 spin_lock(&user_list_lock);
1568 as->next = user_list;
1569 user_list = as;
1570 spin_unlock(&user_list_lock);
1571 filp->private_data = as;
1572 return 0;
1575 static int proc_apm_show(struct seq_file *m, void *v)
1577 unsigned short bx;
1578 unsigned short cx;
1579 unsigned short dx;
1580 int error;
1581 unsigned short ac_line_status = 0xff;
1582 unsigned short battery_status = 0xff;
1583 unsigned short battery_flag = 0xff;
1584 int percentage = -1;
1585 int time_units = -1;
1586 char *units = "?";
1588 if ((num_online_cpus() == 1) &&
1589 !(error = apm_get_power_status(&bx, &cx, &dx))) {
1590 ac_line_status = (bx >> 8) & 0xff;
1591 battery_status = bx & 0xff;
1592 if ((cx & 0xff) != 0xff)
1593 percentage = cx & 0xff;
1595 if (apm_info.connection_version > 0x100) {
1596 battery_flag = (cx >> 8) & 0xff;
1597 if (dx != 0xffff) {
1598 units = (dx & 0x8000) ? "min" : "sec";
1599 time_units = dx & 0x7fff;
1603 /* Arguments, with symbols from linux/apm_bios.h. Information is
1604 from the Get Power Status (0x0a) call unless otherwise noted.
1606 0) Linux driver version (this will change if format changes)
1607 1) APM BIOS Version. Usually 1.0, 1.1 or 1.2.
1608 2) APM flags from APM Installation Check (0x00):
1609 bit 0: APM_16_BIT_SUPPORT
1610 bit 1: APM_32_BIT_SUPPORT
1611 bit 2: APM_IDLE_SLOWS_CLOCK
1612 bit 3: APM_BIOS_DISABLED
1613 bit 4: APM_BIOS_DISENGAGED
1614 3) AC line status
1615 0x00: Off-line
1616 0x01: On-line
1617 0x02: On backup power (BIOS >= 1.1 only)
1618 0xff: Unknown
1619 4) Battery status
1620 0x00: High
1621 0x01: Low
1622 0x02: Critical
1623 0x03: Charging
1624 0x04: Selected battery not present (BIOS >= 1.2 only)
1625 0xff: Unknown
1626 5) Battery flag
1627 bit 0: High
1628 bit 1: Low
1629 bit 2: Critical
1630 bit 3: Charging
1631 bit 7: No system battery
1632 0xff: Unknown
1633 6) Remaining battery life (percentage of charge):
1634 0-100: valid
1635 -1: Unknown
1636 7) Remaining battery life (time units):
1637 Number of remaining minutes or seconds
1638 -1: Unknown
1639 8) min = minutes; sec = seconds */
1641 seq_printf(m, "%s %d.%d 0x%02x 0x%02x 0x%02x 0x%02x %d%% %d %s\n",
1642 driver_version,
1643 (apm_info.bios.version >> 8) & 0xff,
1644 apm_info.bios.version & 0xff,
1645 apm_info.bios.flags,
1646 ac_line_status,
1647 battery_status,
1648 battery_flag,
1649 percentage,
1650 time_units,
1651 units);
1652 return 0;
1655 static int proc_apm_open(struct inode *inode, struct file *file)
1657 return single_open(file, proc_apm_show, NULL);
1660 static const struct file_operations apm_file_ops = {
1661 .owner = THIS_MODULE,
1662 .open = proc_apm_open,
1663 .read = seq_read,
1664 .llseek = seq_lseek,
1665 .release = single_release,
1668 static int apm(void *unused)
1670 unsigned short bx;
1671 unsigned short cx;
1672 unsigned short dx;
1673 int error;
1674 char *power_stat;
1675 char *bat_stat;
1677 #ifdef CONFIG_SMP
1678 /* 2002/08/01 - WT
1679 * This is to avoid random crashes at boot time during initialization
1680 * on SMP systems in case of "apm=power-off" mode. Seen on ASUS A7M266D.
1681 * Some bioses don't like being called from CPU != 0.
1682 * Method suggested by Ingo Molnar.
1684 set_cpus_allowed(current, cpumask_of_cpu(0));
1685 BUG_ON(smp_processor_id() != 0);
1686 #endif
1688 if (apm_info.connection_version == 0) {
1689 apm_info.connection_version = apm_info.bios.version;
1690 if (apm_info.connection_version > 0x100) {
1692 * We only support BIOSs up to version 1.2
1694 if (apm_info.connection_version > 0x0102)
1695 apm_info.connection_version = 0x0102;
1696 error = apm_driver_version(&apm_info.connection_version);
1697 if (error != APM_SUCCESS) {
1698 apm_error("driver version", error);
1699 /* Fall back to an APM 1.0 connection. */
1700 apm_info.connection_version = 0x100;
1705 if (debug)
1706 printk(KERN_INFO "apm: Connection version %d.%d\n",
1707 (apm_info.connection_version >> 8) & 0xff,
1708 apm_info.connection_version & 0xff);
1710 #ifdef CONFIG_APM_DO_ENABLE
1711 if (apm_info.bios.flags & APM_BIOS_DISABLED) {
1713 * This call causes my NEC UltraLite Versa 33/C to hang if it
1714 * is booted with PM disabled but not in the docking station.
1715 * Unfortunate ...
1717 error = apm_enable_power_management(1);
1718 if (error) {
1719 apm_error("enable power management", error);
1720 return -1;
1723 #endif
1725 if ((apm_info.bios.flags & APM_BIOS_DISENGAGED)
1726 && (apm_info.connection_version > 0x0100)) {
1727 error = apm_engage_power_management(APM_DEVICE_ALL, 1);
1728 if (error) {
1729 apm_error("engage power management", error);
1730 return -1;
1734 if (debug && (num_online_cpus() == 1 || smp)) {
1735 error = apm_get_power_status(&bx, &cx, &dx);
1736 if (error)
1737 printk(KERN_INFO "apm: power status not available\n");
1738 else {
1739 switch ((bx >> 8) & 0xff) {
1740 case 0:
1741 power_stat = "off line";
1742 break;
1743 case 1:
1744 power_stat = "on line";
1745 break;
1746 case 2:
1747 power_stat = "on backup power";
1748 break;
1749 default:
1750 power_stat = "unknown";
1751 break;
1753 switch (bx & 0xff) {
1754 case 0:
1755 bat_stat = "high";
1756 break;
1757 case 1:
1758 bat_stat = "low";
1759 break;
1760 case 2:
1761 bat_stat = "critical";
1762 break;
1763 case 3:
1764 bat_stat = "charging";
1765 break;
1766 default:
1767 bat_stat = "unknown";
1768 break;
1770 printk(KERN_INFO
1771 "apm: AC %s, battery status %s, battery life ",
1772 power_stat, bat_stat);
1773 if ((cx & 0xff) == 0xff)
1774 printk("unknown\n");
1775 else
1776 printk("%d%%\n", cx & 0xff);
1777 if (apm_info.connection_version > 0x100) {
1778 printk(KERN_INFO
1779 "apm: battery flag 0x%02x, battery life ",
1780 (cx >> 8) & 0xff);
1781 if (dx == 0xffff)
1782 printk("unknown\n");
1783 else
1784 printk("%d %s\n", dx & 0x7fff,
1785 (dx & 0x8000) ?
1786 "minutes" : "seconds");
1791 /* Install our power off handler.. */
1792 if (power_off)
1793 pm_power_off = apm_power_off;
1795 if (num_online_cpus() == 1 || smp) {
1796 #if defined(CONFIG_APM_DISPLAY_BLANK) && defined(CONFIG_VT)
1797 console_blank_hook = apm_console_blank;
1798 #endif
1799 apm_mainloop();
1800 #if defined(CONFIG_APM_DISPLAY_BLANK) && defined(CONFIG_VT)
1801 console_blank_hook = NULL;
1802 #endif
1805 return 0;
1808 #ifndef MODULE
1809 static int __init apm_setup(char *str)
1811 int invert;
1813 while ((str != NULL) && (*str != '\0')) {
1814 if (strncmp(str, "off", 3) == 0)
1815 apm_disabled = 1;
1816 if (strncmp(str, "on", 2) == 0)
1817 apm_disabled = 0;
1818 if ((strncmp(str, "bounce-interval=", 16) == 0) ||
1819 (strncmp(str, "bounce_interval=", 16) == 0))
1820 bounce_interval = simple_strtol(str + 16, NULL, 0);
1821 if ((strncmp(str, "idle-threshold=", 15) == 0) ||
1822 (strncmp(str, "idle_threshold=", 15) == 0))
1823 idle_threshold = simple_strtol(str + 15, NULL, 0);
1824 if ((strncmp(str, "idle-period=", 12) == 0) ||
1825 (strncmp(str, "idle_period=", 12) == 0))
1826 idle_period = simple_strtol(str + 12, NULL, 0);
1827 invert = (strncmp(str, "no-", 3) == 0) ||
1828 (strncmp(str, "no_", 3) == 0);
1829 if (invert)
1830 str += 3;
1831 if (strncmp(str, "debug", 5) == 0)
1832 debug = !invert;
1833 if ((strncmp(str, "power-off", 9) == 0) ||
1834 (strncmp(str, "power_off", 9) == 0))
1835 power_off = !invert;
1836 if (strncmp(str, "smp", 3) == 0) {
1837 smp = !invert;
1838 idle_threshold = 100;
1840 if ((strncmp(str, "allow-ints", 10) == 0) ||
1841 (strncmp(str, "allow_ints", 10) == 0))
1842 apm_info.allow_ints = !invert;
1843 if ((strncmp(str, "broken-psr", 10) == 0) ||
1844 (strncmp(str, "broken_psr", 10) == 0))
1845 apm_info.get_power_status_broken = !invert;
1846 if ((strncmp(str, "realmode-power-off", 18) == 0) ||
1847 (strncmp(str, "realmode_power_off", 18) == 0))
1848 apm_info.realmode_power_off = !invert;
1849 str = strchr(str, ',');
1850 if (str != NULL)
1851 str += strspn(str, ", \t");
1853 return 1;
1856 __setup("apm=", apm_setup);
1857 #endif
1859 static const struct file_operations apm_bios_fops = {
1860 .owner = THIS_MODULE,
1861 .read = do_read,
1862 .poll = do_poll,
1863 .ioctl = do_ioctl,
1864 .open = do_open,
1865 .release = do_release,
1868 static struct miscdevice apm_device = {
1869 APM_MINOR_DEV,
1870 "apm_bios",
1871 &apm_bios_fops
1875 /* Simple "print if true" callback */
1876 static int __init print_if_true(const struct dmi_system_id *d)
1878 printk("%s\n", d->ident);
1879 return 0;
1883 * Some Bioses enable the PS/2 mouse (touchpad) at resume, even if it was
1884 * disabled before the suspend. Linux used to get terribly confused by that.
1886 static int __init broken_ps2_resume(const struct dmi_system_id *d)
1888 printk(KERN_INFO "%s machine detected. Mousepad Resume Bug "
1889 "workaround hopefully not needed.\n", d->ident);
1890 return 0;
1893 /* Some bioses have a broken protected mode poweroff and need to use realmode */
1894 static int __init set_realmode_power_off(const struct dmi_system_id *d)
1896 if (apm_info.realmode_power_off == 0) {
1897 apm_info.realmode_power_off = 1;
1898 printk(KERN_INFO "%s bios detected. "
1899 "Using realmode poweroff only.\n", d->ident);
1901 return 0;
1904 /* Some laptops require interrupts to be enabled during APM calls */
1905 static int __init set_apm_ints(const struct dmi_system_id *d)
1907 if (apm_info.allow_ints == 0) {
1908 apm_info.allow_ints = 1;
1909 printk(KERN_INFO "%s machine detected. "
1910 "Enabling interrupts during APM calls.\n", d->ident);
1912 return 0;
1915 /* Some APM bioses corrupt memory or just plain do not work */
1916 static int __init apm_is_horked(const struct dmi_system_id *d)
1918 if (apm_info.disabled == 0) {
1919 apm_info.disabled = 1;
1920 printk(KERN_INFO "%s machine detected. "
1921 "Disabling APM.\n", d->ident);
1923 return 0;
1926 static int __init apm_is_horked_d850md(const struct dmi_system_id *d)
1928 if (apm_info.disabled == 0) {
1929 apm_info.disabled = 1;
1930 printk(KERN_INFO "%s machine detected. "
1931 "Disabling APM.\n", d->ident);
1932 printk(KERN_INFO "This bug is fixed in bios P15 which is available for \n");
1933 printk(KERN_INFO "download from support.intel.com \n");
1935 return 0;
1938 /* Some APM bioses hang on APM idle calls */
1939 static int __init apm_likes_to_melt(const struct dmi_system_id *d)
1941 if (apm_info.forbid_idle == 0) {
1942 apm_info.forbid_idle = 1;
1943 printk(KERN_INFO "%s machine detected. "
1944 "Disabling APM idle calls.\n", d->ident);
1946 return 0;
1950 * Check for clue free BIOS implementations who use
1951 * the following QA technique
1953 * [ Write BIOS Code ]<------
1954 * | ^
1955 * < Does it Compile >----N--
1956 * |Y ^
1957 * < Does it Boot Win98 >-N--
1958 * |Y
1959 * [Ship It]
1961 * Phoenix A04 08/24/2000 is known bad (Dell Inspiron 5000e)
1962 * Phoenix A07 09/29/2000 is known good (Dell Inspiron 5000)
1964 static int __init broken_apm_power(const struct dmi_system_id *d)
1966 apm_info.get_power_status_broken = 1;
1967 printk(KERN_WARNING "BIOS strings suggest APM bugs, "
1968 "disabling power status reporting.\n");
1969 return 0;
1973 * This bios swaps the APM minute reporting bytes over (Many sony laptops
1974 * have this problem).
1976 static int __init swab_apm_power_in_minutes(const struct dmi_system_id *d)
1978 apm_info.get_power_status_swabinminutes = 1;
1979 printk(KERN_WARNING "BIOS strings suggest APM reports battery life "
1980 "in minutes and wrong byte order.\n");
1981 return 0;
1984 static struct dmi_system_id __initdata apm_dmi_table[] = {
1986 print_if_true,
1987 KERN_WARNING "IBM T23 - BIOS 1.03b+ and controller firmware 1.02+ may be needed for Linux APM.",
1988 { DMI_MATCH(DMI_SYS_VENDOR, "IBM"),
1989 DMI_MATCH(DMI_BIOS_VERSION, "1AET38WW (1.01b)"), },
1991 { /* Handle problems with APM on the C600 */
1992 broken_ps2_resume, "Dell Latitude C600",
1993 { DMI_MATCH(DMI_SYS_VENDOR, "Dell"),
1994 DMI_MATCH(DMI_PRODUCT_NAME, "Latitude C600"), },
1996 { /* Allow interrupts during suspend on Dell Latitude laptops*/
1997 set_apm_ints, "Dell Latitude",
1998 { DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
1999 DMI_MATCH(DMI_PRODUCT_NAME, "Latitude C510"), }
2001 { /* APM crashes */
2002 apm_is_horked, "Dell Inspiron 2500",
2003 { DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
2004 DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 2500"),
2005 DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2006 DMI_MATCH(DMI_BIOS_VERSION, "A11"), },
2008 { /* Allow interrupts during suspend on Dell Inspiron laptops*/
2009 set_apm_ints, "Dell Inspiron", {
2010 DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
2011 DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 4000"), },
2013 { /* Handle problems with APM on Inspiron 5000e */
2014 broken_apm_power, "Dell Inspiron 5000e",
2015 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2016 DMI_MATCH(DMI_BIOS_VERSION, "A04"),
2017 DMI_MATCH(DMI_BIOS_DATE, "08/24/2000"), },
2019 { /* Handle problems with APM on Inspiron 2500 */
2020 broken_apm_power, "Dell Inspiron 2500",
2021 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2022 DMI_MATCH(DMI_BIOS_VERSION, "A12"),
2023 DMI_MATCH(DMI_BIOS_DATE, "02/04/2002"), },
2025 { /* APM crashes */
2026 apm_is_horked, "Dell Dimension 4100",
2027 { DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
2028 DMI_MATCH(DMI_PRODUCT_NAME, "XPS-Z"),
2029 DMI_MATCH(DMI_BIOS_VENDOR, "Intel Corp."),
2030 DMI_MATCH(DMI_BIOS_VERSION, "A11"), },
2032 { /* Allow interrupts during suspend on Compaq Laptops*/
2033 set_apm_ints, "Compaq 12XL125",
2034 { DMI_MATCH(DMI_SYS_VENDOR, "Compaq"),
2035 DMI_MATCH(DMI_PRODUCT_NAME, "Compaq PC"),
2036 DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2037 DMI_MATCH(DMI_BIOS_VERSION, "4.06"), },
2039 { /* Allow interrupts during APM or the clock goes slow */
2040 set_apm_ints, "ASUSTeK",
2041 { DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK Computer Inc."),
2042 DMI_MATCH(DMI_PRODUCT_NAME, "L8400K series Notebook PC"), },
2044 { /* APM blows on shutdown */
2045 apm_is_horked, "ABIT KX7-333[R]",
2046 { DMI_MATCH(DMI_BOARD_VENDOR, "ABIT"),
2047 DMI_MATCH(DMI_BOARD_NAME, "VT8367-8233A (KX7-333[R])"), },
2049 { /* APM crashes */
2050 apm_is_horked, "Trigem Delhi3",
2051 { DMI_MATCH(DMI_SYS_VENDOR, "TriGem Computer, Inc"),
2052 DMI_MATCH(DMI_PRODUCT_NAME, "Delhi3"), },
2054 { /* APM crashes */
2055 apm_is_horked, "Fujitsu-Siemens",
2056 { DMI_MATCH(DMI_BIOS_VENDOR, "hoenix/FUJITSU SIEMENS"),
2057 DMI_MATCH(DMI_BIOS_VERSION, "Version1.01"), },
2059 { /* APM crashes */
2060 apm_is_horked_d850md, "Intel D850MD",
2061 { DMI_MATCH(DMI_BIOS_VENDOR, "Intel Corp."),
2062 DMI_MATCH(DMI_BIOS_VERSION, "MV85010A.86A.0016.P07.0201251536"), },
2064 { /* APM crashes */
2065 apm_is_horked, "Intel D810EMO",
2066 { DMI_MATCH(DMI_BIOS_VENDOR, "Intel Corp."),
2067 DMI_MATCH(DMI_BIOS_VERSION, "MO81010A.86A.0008.P04.0004170800"), },
2069 { /* APM crashes */
2070 apm_is_horked, "Dell XPS-Z",
2071 { DMI_MATCH(DMI_BIOS_VENDOR, "Intel Corp."),
2072 DMI_MATCH(DMI_BIOS_VERSION, "A11"),
2073 DMI_MATCH(DMI_PRODUCT_NAME, "XPS-Z"), },
2075 { /* APM crashes */
2076 apm_is_horked, "Sharp PC-PJ/AX",
2077 { DMI_MATCH(DMI_SYS_VENDOR, "SHARP"),
2078 DMI_MATCH(DMI_PRODUCT_NAME, "PC-PJ/AX"),
2079 DMI_MATCH(DMI_BIOS_VENDOR, "SystemSoft"),
2080 DMI_MATCH(DMI_BIOS_VERSION, "Version R2.08"), },
2082 { /* APM crashes */
2083 apm_is_horked, "Dell Inspiron 2500",
2084 { DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
2085 DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 2500"),
2086 DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2087 DMI_MATCH(DMI_BIOS_VERSION, "A11"), },
2089 { /* APM idle hangs */
2090 apm_likes_to_melt, "Jabil AMD",
2091 { DMI_MATCH(DMI_BIOS_VENDOR, "American Megatrends Inc."),
2092 DMI_MATCH(DMI_BIOS_VERSION, "0AASNP06"), },
2094 { /* APM idle hangs */
2095 apm_likes_to_melt, "AMI Bios",
2096 { DMI_MATCH(DMI_BIOS_VENDOR, "American Megatrends Inc."),
2097 DMI_MATCH(DMI_BIOS_VERSION, "0AASNP05"), },
2099 { /* Handle problems with APM on Sony Vaio PCG-N505X(DE) */
2100 swab_apm_power_in_minutes, "Sony VAIO",
2101 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2102 DMI_MATCH(DMI_BIOS_VERSION, "R0206H"),
2103 DMI_MATCH(DMI_BIOS_DATE, "08/23/99"), },
2105 { /* Handle problems with APM on Sony Vaio PCG-N505VX */
2106 swab_apm_power_in_minutes, "Sony VAIO",
2107 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2108 DMI_MATCH(DMI_BIOS_VERSION, "W2K06H0"),
2109 DMI_MATCH(DMI_BIOS_DATE, "02/03/00"), },
2111 { /* Handle problems with APM on Sony Vaio PCG-XG29 */
2112 swab_apm_power_in_minutes, "Sony VAIO",
2113 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2114 DMI_MATCH(DMI_BIOS_VERSION, "R0117A0"),
2115 DMI_MATCH(DMI_BIOS_DATE, "04/25/00"), },
2117 { /* Handle problems with APM on Sony Vaio PCG-Z600NE */
2118 swab_apm_power_in_minutes, "Sony VAIO",
2119 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2120 DMI_MATCH(DMI_BIOS_VERSION, "R0121Z1"),
2121 DMI_MATCH(DMI_BIOS_DATE, "05/11/00"), },
2123 { /* Handle problems with APM on Sony Vaio PCG-Z600NE */
2124 swab_apm_power_in_minutes, "Sony VAIO",
2125 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2126 DMI_MATCH(DMI_BIOS_VERSION, "WME01Z1"),
2127 DMI_MATCH(DMI_BIOS_DATE, "08/11/00"), },
2129 { /* Handle problems with APM on Sony Vaio PCG-Z600LEK(DE) */
2130 swab_apm_power_in_minutes, "Sony VAIO",
2131 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2132 DMI_MATCH(DMI_BIOS_VERSION, "R0206Z3"),
2133 DMI_MATCH(DMI_BIOS_DATE, "12/25/00"), },
2135 { /* Handle problems with APM on Sony Vaio PCG-Z505LS */
2136 swab_apm_power_in_minutes, "Sony VAIO",
2137 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2138 DMI_MATCH(DMI_BIOS_VERSION, "R0203D0"),
2139 DMI_MATCH(DMI_BIOS_DATE, "05/12/00"), },
2141 { /* Handle problems with APM on Sony Vaio PCG-Z505LS */
2142 swab_apm_power_in_minutes, "Sony VAIO",
2143 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2144 DMI_MATCH(DMI_BIOS_VERSION, "R0203Z3"),
2145 DMI_MATCH(DMI_BIOS_DATE, "08/25/00"), },
2147 { /* Handle problems with APM on Sony Vaio PCG-Z505LS (with updated BIOS) */
2148 swab_apm_power_in_minutes, "Sony VAIO",
2149 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2150 DMI_MATCH(DMI_BIOS_VERSION, "R0209Z3"),
2151 DMI_MATCH(DMI_BIOS_DATE, "05/12/01"), },
2153 { /* Handle problems with APM on Sony Vaio PCG-F104K */
2154 swab_apm_power_in_minutes, "Sony VAIO",
2155 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2156 DMI_MATCH(DMI_BIOS_VERSION, "R0204K2"),
2157 DMI_MATCH(DMI_BIOS_DATE, "08/28/00"), },
2160 { /* Handle problems with APM on Sony Vaio PCG-C1VN/C1VE */
2161 swab_apm_power_in_minutes, "Sony VAIO",
2162 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2163 DMI_MATCH(DMI_BIOS_VERSION, "R0208P1"),
2164 DMI_MATCH(DMI_BIOS_DATE, "11/09/00"), },
2166 { /* Handle problems with APM on Sony Vaio PCG-C1VE */
2167 swab_apm_power_in_minutes, "Sony VAIO",
2168 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2169 DMI_MATCH(DMI_BIOS_VERSION, "R0204P1"),
2170 DMI_MATCH(DMI_BIOS_DATE, "09/12/00"), },
2172 { /* Handle problems with APM on Sony Vaio PCG-C1VE */
2173 swab_apm_power_in_minutes, "Sony VAIO",
2174 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2175 DMI_MATCH(DMI_BIOS_VERSION, "WXPO1Z3"),
2176 DMI_MATCH(DMI_BIOS_DATE, "10/26/01"), },
2178 { /* broken PM poweroff bios */
2179 set_realmode_power_off, "Award Software v4.60 PGMA",
2180 { DMI_MATCH(DMI_BIOS_VENDOR, "Award Software International, Inc."),
2181 DMI_MATCH(DMI_BIOS_VERSION, "4.60 PGMA"),
2182 DMI_MATCH(DMI_BIOS_DATE, "134526184"), },
2185 /* Generic per vendor APM settings */
2187 { /* Allow interrupts during suspend on IBM laptops */
2188 set_apm_ints, "IBM",
2189 { DMI_MATCH(DMI_SYS_VENDOR, "IBM"), },
2196 * Just start the APM thread. We do NOT want to do APM BIOS
2197 * calls from anything but the APM thread, if for no other reason
2198 * than the fact that we don't trust the APM BIOS. This way,
2199 * most common APM BIOS problems that lead to protection errors
2200 * etc will have at least some level of being contained...
2202 * In short, if something bad happens, at least we have a choice
2203 * of just killing the apm thread..
2205 static int __init apm_init(void)
2207 struct desc_struct *gdt;
2208 int err;
2210 dmi_check_system(apm_dmi_table);
2212 if (apm_info.bios.version == 0 || paravirt_enabled()) {
2213 printk(KERN_INFO "apm: BIOS not found.\n");
2214 return -ENODEV;
2216 printk(KERN_INFO
2217 "apm: BIOS version %d.%d Flags 0x%02x (Driver version %s)\n",
2218 ((apm_info.bios.version >> 8) & 0xff),
2219 (apm_info.bios.version & 0xff),
2220 apm_info.bios.flags,
2221 driver_version);
2222 if ((apm_info.bios.flags & APM_32_BIT_SUPPORT) == 0) {
2223 printk(KERN_INFO "apm: no 32 bit BIOS support\n");
2224 return -ENODEV;
2227 if (allow_ints)
2228 apm_info.allow_ints = 1;
2229 if (broken_psr)
2230 apm_info.get_power_status_broken = 1;
2231 if (realmode_power_off)
2232 apm_info.realmode_power_off = 1;
2233 /* User can override, but default is to trust DMI */
2234 if (apm_disabled != -1)
2235 apm_info.disabled = apm_disabled;
2238 * Fix for the Compaq Contura 3/25c which reports BIOS version 0.1
2239 * but is reportedly a 1.0 BIOS.
2241 if (apm_info.bios.version == 0x001)
2242 apm_info.bios.version = 0x100;
2244 /* BIOS < 1.2 doesn't set cseg_16_len */
2245 if (apm_info.bios.version < 0x102)
2246 apm_info.bios.cseg_16_len = 0; /* 64k */
2248 if (debug) {
2249 printk(KERN_INFO "apm: entry %x:%x cseg16 %x dseg %x",
2250 apm_info.bios.cseg, apm_info.bios.offset,
2251 apm_info.bios.cseg_16, apm_info.bios.dseg);
2252 if (apm_info.bios.version > 0x100)
2253 printk(" cseg len %x, dseg len %x",
2254 apm_info.bios.cseg_len,
2255 apm_info.bios.dseg_len);
2256 if (apm_info.bios.version > 0x101)
2257 printk(" cseg16 len %x", apm_info.bios.cseg_16_len);
2258 printk("\n");
2261 if (apm_info.disabled) {
2262 printk(KERN_NOTICE "apm: disabled on user request.\n");
2263 return -ENODEV;
2265 if ((num_online_cpus() > 1) && !power_off && !smp) {
2266 printk(KERN_NOTICE "apm: disabled - APM is not SMP safe.\n");
2267 apm_info.disabled = 1;
2268 return -ENODEV;
2270 if (pm_flags & PM_ACPI) {
2271 printk(KERN_NOTICE "apm: overridden by ACPI.\n");
2272 apm_info.disabled = 1;
2273 return -ENODEV;
2275 pm_flags |= PM_APM;
2278 * Set up a segment that references the real mode segment 0x40
2279 * that extends up to the end of page zero (that we have reserved).
2280 * This is for buggy BIOS's that refer to (real mode) segment 0x40
2281 * even though they are called in protected mode.
2283 set_base(bad_bios_desc, __va((unsigned long)0x40 << 4));
2284 _set_limit((char *)&bad_bios_desc, 4095 - (0x40 << 4));
2287 * Set up the long jump entry point to the APM BIOS, which is called
2288 * from inline assembly.
2290 apm_bios_entry.offset = apm_info.bios.offset;
2291 apm_bios_entry.segment = APM_CS;
2294 * The APM 1.1 BIOS is supposed to provide limit information that it
2295 * recognizes. Many machines do this correctly, but many others do
2296 * not restrict themselves to their claimed limit. When this happens,
2297 * they will cause a segmentation violation in the kernel at boot time.
2298 * Most BIOS's, however, will respect a 64k limit, so we use that.
2300 * Note we only set APM segments on CPU zero, since we pin the APM
2301 * code to that CPU.
2303 gdt = get_cpu_gdt_table(0);
2304 set_base(gdt[APM_CS >> 3],
2305 __va((unsigned long)apm_info.bios.cseg << 4));
2306 set_base(gdt[APM_CS_16 >> 3],
2307 __va((unsigned long)apm_info.bios.cseg_16 << 4));
2308 set_base(gdt[APM_DS >> 3],
2309 __va((unsigned long)apm_info.bios.dseg << 4));
2311 proc_create("apm", 0, NULL, &apm_file_ops);
2313 kapmd_task = kthread_create(apm, NULL, "kapmd");
2314 if (IS_ERR(kapmd_task)) {
2315 printk(KERN_ERR "apm: disabled - Unable to start kernel "
2316 "thread.\n");
2317 err = PTR_ERR(kapmd_task);
2318 kapmd_task = NULL;
2319 remove_proc_entry("apm", NULL);
2320 return err;
2322 wake_up_process(kapmd_task);
2324 if (num_online_cpus() > 1 && !smp) {
2325 printk(KERN_NOTICE
2326 "apm: disabled - APM is not SMP safe (power off active).\n");
2327 return 0;
2331 * Note we don't actually care if the misc_device cannot be registered.
2332 * this driver can do its job without it, even if userspace can't
2333 * control it. just log the error
2335 if (misc_register(&apm_device))
2336 printk(KERN_WARNING "apm: Could not register misc device.\n");
2338 if (HZ != 100)
2339 idle_period = (idle_period * HZ) / 100;
2340 if (idle_threshold < 100) {
2341 original_pm_idle = pm_idle;
2342 pm_idle = apm_cpu_idle;
2343 set_pm_idle = 1;
2346 return 0;
2349 static void __exit apm_exit(void)
2351 int error;
2353 if (set_pm_idle) {
2354 pm_idle = original_pm_idle;
2356 * We are about to unload the current idle thread pm callback
2357 * (pm_idle), Wait for all processors to update cached/local
2358 * copies of pm_idle before proceeding.
2360 cpu_idle_wait();
2362 if (((apm_info.bios.flags & APM_BIOS_DISENGAGED) == 0)
2363 && (apm_info.connection_version > 0x0100)) {
2364 error = apm_engage_power_management(APM_DEVICE_ALL, 0);
2365 if (error)
2366 apm_error("disengage power management", error);
2368 misc_deregister(&apm_device);
2369 remove_proc_entry("apm", NULL);
2370 if (power_off)
2371 pm_power_off = NULL;
2372 if (kapmd_task) {
2373 kthread_stop(kapmd_task);
2374 kapmd_task = NULL;
2376 pm_flags &= ~PM_APM;
2379 module_init(apm_init);
2380 module_exit(apm_exit);
2382 MODULE_AUTHOR("Stephen Rothwell");
2383 MODULE_DESCRIPTION("Advanced Power Management");
2384 MODULE_LICENSE("GPL");
2385 module_param(debug, bool, 0644);
2386 MODULE_PARM_DESC(debug, "Enable debug mode");
2387 module_param(power_off, bool, 0444);
2388 MODULE_PARM_DESC(power_off, "Enable power off");
2389 module_param(bounce_interval, int, 0444);
2390 MODULE_PARM_DESC(bounce_interval,
2391 "Set the number of ticks to ignore suspend bounces");
2392 module_param(allow_ints, bool, 0444);
2393 MODULE_PARM_DESC(allow_ints, "Allow interrupts during BIOS calls");
2394 module_param(broken_psr, bool, 0444);
2395 MODULE_PARM_DESC(broken_psr, "BIOS has a broken GetPowerStatus call");
2396 module_param(realmode_power_off, bool, 0444);
2397 MODULE_PARM_DESC(realmode_power_off,
2398 "Switch to real mode before powering off");
2399 module_param(idle_threshold, int, 0444);
2400 MODULE_PARM_DESC(idle_threshold,
2401 "System idle percentage above which to make APM BIOS idle calls");
2402 module_param(idle_period, int, 0444);
2403 MODULE_PARM_DESC(idle_period,
2404 "Period (in sec/100) over which to caculate the idle percentage");
2405 module_param(smp, bool, 0444);
2406 MODULE_PARM_DESC(smp,
2407 "Set this to enable APM use on an SMP platform. Use with caution on older systems");
2408 MODULE_ALIAS_MISCDEV(APM_MINOR_DEV);