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[linux-2.6-block.git] / arch / i386 / kernel / apm.c
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1da177e4
LT		 1/* -*- linux-c -*-
2 * APM BIOS driver for Linux
3 * Copyright 1994-2001 Stephen Rothwell (sfr@canb.auug.org.au)
4 *
5 * Initial development of this driver was funded by NEC Australia P/L
6 * and NEC Corporation
7 *
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.
12 *
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.
17 *
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
44 *
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 replacment 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.
184 *
185 * APM 1.1 Reference:
186 *
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.
190 *
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.]
195 *
196 * APM 1.2 Reference:
197 * Intel Corporation, Microsoft Corporation. Advanced Power Management
198 * (APM) BIOS Interface Specification, Revision 1.2, February 1996.
199 *
200 * [This document is available from Microsoft at:
201 * http://www.microsoft.com/hwdev/busbios/amp_12.htm]
202 */
203
1da177e4
LT		 204#include <linux/module.h>
205
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/miscdevice.h>
215#include <linux/apm_bios.h>
216#include <linux/init.h>
217#include <linux/time.h>
218#include <linux/sched.h>
219#include <linux/pm.h>
bca73e4b 220#include <linux/pm_legacy.h>
a9415644 221#include <linux/capability.h>
1da177e4
LT		 222#include <linux/device.h>
223#include <linux/kernel.h>
224#include <linux/smp.h>
225#include <linux/smp_lock.h>
226#include <linux/dmi.h>
227#include <linux/suspend.h>
228
229#include <asm/system.h>
230#include <asm/uaccess.h>
231#include <asm/desc.h>
306e440d 232#include <asm/i8253.h>
1da177e4
LT		 233
234#include "io_ports.h"
235
1da177e4
LT		 236extern unsigned long get_cmos_time(void);
237extern void machine_real_restart(unsigned char *, int);
238
239#if defined(CONFIG_APM_DISPLAY_BLANK) && defined(CONFIG_VT)
240extern int (*console_blank_hook)(int);
241#endif
242
243/*
244 * The apm_bios device is one of the misc char devices.
245 * This is its minor number.
246 */
247#define APM_MINOR_DEV 134
248
249/*
250 * See Documentation/Config.help for the configuration options.
251 *
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.
270 */
271
272/* KNOWN PROBLEM MACHINES:
273 *
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
284 *
285 * Legend: U = unusable with APM patches
286 * P = partially usable with APM patches
287 */
288
289/*
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.
293 */
294#define ALWAYS_CALL_BUSY 1
295
296/*
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).
300 */
301#define APM_ZERO_SEGS
302
303#include "apm.h"
304
1da177e4
LT		 305/*
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>
309 */
310#undef INIT_TIMER_AFTER_SUSPEND
311
312#ifdef INIT_TIMER_AFTER_SUSPEND
313#include <linux/timex.h>
314#include <asm/io.h>
315#include <linux/delay.h>
316#endif
317
318/*
319 * Need to poll the APM BIOS every second
320 */
321#define APM_CHECK_TIMEOUT (HZ)
322
323/*
324 * Ignore suspend events for this amount of time after a resume
325 */
326#define DEFAULT_BOUNCE_INTERVAL (3 * HZ)
327
328/*
329 * Maximum number of events stored
330 */
331#define APM_MAX_EVENTS 20
332
333/*
334 * The per-file APM data
335 */
336struct apm_user {
337 int magic;
338 struct apm_user * next;
77617bd8
DP		 339 unsigned int suser: 1;
340 unsigned int writer: 1;
341 unsigned int reader: 1;
342 unsigned int suspend_wait: 1;
1da177e4
LT		 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];
351};
352
353/*
354 * The magic number in apm_user
355 */
356#define APM_BIOS_MAGIC 0x4101
357
358/*
359 * idle percentage above which bios idle calls are done
360 */
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)
367
368/*
369 * Local variables
370 */
371static struct {
372 unsigned long offset;
373 unsigned short segment;
374} apm_bios_entry;
375static int clock_slowed;
87af2ffd
AM		 376static int idle_threshold __read_mostly = DEFAULT_IDLE_THRESHOLD;
377static int idle_period __read_mostly = DEFAULT_IDLE_PERIOD;
1da177e4
LT		 378static int set_pm_idle;
379static int suspends_pending;
380static int standbys_pending;
381static int ignore_sys_suspend;
382static int ignore_normal_resume;
87af2ffd 383static int bounce_interval __read_mostly = DEFAULT_BOUNCE_INTERVAL;
1da177e4
LT		 384
385#ifdef CONFIG_APM_RTC_IS_GMT
386# define clock_cmos_diff 0
387# define got_clock_diff 1
388#else
389static long clock_cmos_diff;
390static int got_clock_diff;
391#endif
87af2ffd
AM		 392static int debug __read_mostly;
393static int smp __read_mostly;
1da177e4
LT		 394static int apm_disabled = -1;
395#ifdef CONFIG_SMP
396static int power_off;
397#else
398static int power_off = 1;
399#endif
400#ifdef CONFIG_APM_REAL_MODE_POWER_OFF
401static int realmode_power_off = 1;
402#else
403static int realmode_power_off;
404#endif
87af2ffd
AM		 405static int exit_kapmd __read_mostly;
406static int kapmd_running __read_mostly;
1da177e4
LT		 407#ifdef CONFIG_APM_ALLOW_INTS
408static int allow_ints = 1;
409#else
410static int allow_ints;
411#endif
412static int broken_psr;
413
414static DECLARE_WAIT_QUEUE_HEAD(apm_waitqueue);
415static DECLARE_WAIT_QUEUE_HEAD(apm_suspend_waitqueue);
416static struct apm_user * user_list;
417static DEFINE_SPINLOCK(user_list_lock);
87af2ffd 418static const struct desc_struct bad_bios_desc = { 0, 0x00409200 };
1da177e4 419
87af2ffd 420static const char driver_version[] = "1.16ac"; /* no spaces */
1da177e4
LT		 421
422/*
423 * APM event names taken from the APM 1.2 specification. These are
424 * the message codes that the BIOS uses to tell us about events
425 */
87af2ffd 426static const char * const apm_event_name[] = {
1da177e4
LT		 427 "system standby",
428 "system suspend",
429 "normal resume",
430 "critical resume",
431 "low battery",
432 "power status change",
433 "update time",
434 "critical suspend",
435 "user standby",
436 "user suspend",
437 "system standby resume",
438 "capabilities change"
439};
38e548ee 440#define NR_APM_EVENT_NAME ARRAY_SIZE(apm_event_name)
1da177e4
LT		 441
442typedef struct lookup_t {
443 int key;
444 char * msg;
445} lookup_t;
446
447/*
448 * The BIOS returns a set of standard error codes in AX when the
449 * carry flag is set.
450 */
451
452static const lookup_t error_table[] = {
453/* N/A { APM_SUCCESS, "Operation succeeded" }, */
454 { APM_DISABLED, "Power management disabled" },
455 { APM_CONNECTED, "Real mode interface already connected" },
456 { APM_NOT_CONNECTED, "Interface not connected" },
457 { APM_16_CONNECTED, "16 bit interface already connected" },
458/* N/A { APM_16_UNSUPPORTED, "16 bit interface not supported" }, */
459 { APM_32_CONNECTED, "32 bit interface already connected" },
460 { APM_32_UNSUPPORTED, "32 bit interface not supported" },
461 { APM_BAD_DEVICE, "Unrecognized device ID" },
462 { APM_BAD_PARAM, "Parameter out of range" },
463 { APM_NOT_ENGAGED, "Interface not engaged" },
464 { APM_BAD_FUNCTION, "Function not supported" },
465 { APM_RESUME_DISABLED, "Resume timer disabled" },
466 { APM_BAD_STATE, "Unable to enter requested state" },
467/* N/A { APM_NO_EVENTS, "No events pending" }, */
468 { APM_NO_ERROR, "BIOS did not set a return code" },
469 { APM_NOT_PRESENT, "No APM present" }
470};
38e548ee 471#define ERROR_COUNT ARRAY_SIZE(error_table)
1da177e4
LT		 472
473/**
474 * apm_error - display an APM error
475 * @str: information string
476 * @err: APM BIOS return code
477 *
478 * Write a meaningful log entry to the kernel log in the event of
479 * an APM error.
480 */
481
482static void apm_error(char *str, int err)
483{
484 int i;
485
486 for (i = 0; i < ERROR_COUNT; i++)
487 if (error_table[i].key == err) break;
488 if (i < ERROR_COUNT)
489 printk(KERN_NOTICE "apm: %s: %s\n", str, error_table[i].msg);
490 else
491 printk(KERN_NOTICE "apm: %s: unknown error code %#2.2x\n",
492 str, err);
493}
494
495/*
496 * Lock APM functionality to physical CPU 0
497 */
498
499#ifdef CONFIG_SMP
500
501static cpumask_t apm_save_cpus(void)
502{
503 cpumask_t x = current->cpus_allowed;
504 /* Some bioses don't like being called from CPU != 0 */
505 set_cpus_allowed(current, cpumask_of_cpu(0));
506 BUG_ON(smp_processor_id() != 0);
507 return x;
508}
509
510static inline void apm_restore_cpus(cpumask_t mask)
511{
512 set_cpus_allowed(current, mask);
513}
514
515#else
516
517/*
518 * No CPU lockdown needed on a uniprocessor
519 */
520
521#define apm_save_cpus() (current->cpus_allowed)
522#define apm_restore_cpus(x) (void)(x)
523
524#endif
525
526/*
527 * These are the actual BIOS calls. Depending on APM_ZERO_SEGS and
528 * apm_info.allow_ints, we are being really paranoid here! Not only
529 * are interrupts disabled, but all the segment registers (except SS)
530 * are saved and zeroed this means that if the BIOS tries to reference
531 * any data without explicitly loading the segment registers, the kernel
532 * will fault immediately rather than have some unforeseen circumstances
533 * for the rest of the kernel. And it will be very obvious! :-) Doing
534 * this depends on CS referring to the same physical memory as DS so that
535 * DS can be zeroed before the call. Unfortunately, we can't do anything
536 * about the stack segment/pointer. Also, we tell the compiler that
537 * everything could change.
538 *
539 * Also, we KNOW that for the non error case of apm_bios_call, there
540 * is no useful data returned in the low order 8 bits of eax.
541 */
542#define APM_DO_CLI \
543 if (apm_info.allow_ints) \
544 local_irq_enable(); \
545 else \
546 local_irq_disable();
547
548#ifdef APM_ZERO_SEGS
549# define APM_DECL_SEGS \
550 unsigned int saved_fs; unsigned int saved_gs;
551# define APM_DO_SAVE_SEGS \
552 savesegment(fs, saved_fs); savesegment(gs, saved_gs)
553# define APM_DO_RESTORE_SEGS \
554 loadsegment(fs, saved_fs); loadsegment(gs, saved_gs)
555#else
556# define APM_DECL_SEGS
557# define APM_DO_SAVE_SEGS
558# define APM_DO_RESTORE_SEGS
559#endif
560
561/**
562 * apm_bios_call - Make an APM BIOS 32bit call
563 * @func: APM function to execute
564 * @ebx_in: EBX register for call entry
565 * @ecx_in: ECX register for call entry
566 * @eax: EAX register return
567 * @ebx: EBX register return
568 * @ecx: ECX register return
569 * @edx: EDX register return
570 * @esi: ESI register return
571 *
572 * Make an APM call using the 32bit protected mode interface. The
573 * caller is responsible for knowing if APM BIOS is configured and
574 * enabled. This call can disable interrupts for a long period of
575 * time on some laptops. The return value is in AH and the carry
576 * flag is loaded into AL. If there is an error, then the error
577 * code is returned in AH (bits 8-15 of eax) and this function
578 * returns non-zero.
579 */
580
581static u8 apm_bios_call(u32 func, u32 ebx_in, u32 ecx_in,
582 u32 *eax, u32 *ebx, u32 *ecx, u32 *edx, u32 *esi)
583{
584 APM_DECL_SEGS
585 unsigned long flags;
586 cpumask_t cpus;
587 int cpu;
588 struct desc_struct save_desc_40;
251e6912 589 struct desc_struct *gdt;
1da177e4
LT		 590
591 cpus = apm_save_cpus();
592
593 cpu = get_cpu();
251e6912
ZA		 594 gdt = get_cpu_gdt_table(cpu);
595 save_desc_40 = gdt[0x40 / 8];
596 gdt[0x40 / 8] = bad_bios_desc;
1da177e4
LT		 597
598 local_save_flags(flags);
599 APM_DO_CLI;
600 APM_DO_SAVE_SEGS;
601 apm_bios_call_asm(func, ebx_in, ecx_in, eax, ebx, ecx, edx, esi);
602 APM_DO_RESTORE_SEGS;
603 local_irq_restore(flags);
251e6912 604 gdt[0x40 / 8] = save_desc_40;
1da177e4
LT		 605 put_cpu();
606 apm_restore_cpus(cpus);
607
608 return *eax & 0xff;
609}
610
611/**
612 * apm_bios_call_simple - make a simple APM BIOS 32bit call
613 * @func: APM function to invoke
614 * @ebx_in: EBX register value for BIOS call
615 * @ecx_in: ECX register value for BIOS call
616 * @eax: EAX register on return from the BIOS call
617 *
87af2ffd 618 * Make a BIOS call that returns one value only, or just status.
1da177e4
LT		 619 * If there is an error, then the error code is returned in AH
620 * (bits 8-15 of eax) and this function returns non-zero. This is
621 * used for simpler BIOS operations. This call may hold interrupts
622 * off for a long time on some laptops.
623 */
624
625static u8 apm_bios_call_simple(u32 func, u32 ebx_in, u32 ecx_in, u32 *eax)
626{
627 u8 error;
628 APM_DECL_SEGS
629 unsigned long flags;
630 cpumask_t cpus;
631 int cpu;
632 struct desc_struct save_desc_40;
251e6912 633 struct desc_struct *gdt;
1da177e4
LT		 634
635 cpus = apm_save_cpus();
636
637 cpu = get_cpu();
251e6912
ZA		 638 gdt = get_cpu_gdt_table(cpu);
639 save_desc_40 = gdt[0x40 / 8];
640 gdt[0x40 / 8] = bad_bios_desc;
1da177e4
LT		 641
642 local_save_flags(flags);
643 APM_DO_CLI;
644 APM_DO_SAVE_SEGS;
645 error = apm_bios_call_simple_asm(func, ebx_in, ecx_in, eax);
646 APM_DO_RESTORE_SEGS;
647 local_irq_restore(flags);
251e6912 648 gdt[0x40 / 8] = save_desc_40;
1da177e4
LT		 649 put_cpu();
650 apm_restore_cpus(cpus);
651 return error;
652}
653
654/**
655 * apm_driver_version - APM driver version
656 * @val: loaded with the APM version on return
657 *
658 * Retrieve the APM version supported by the BIOS. This is only
659 * supported for APM 1.1 or higher. An error indicates APM 1.0 is
660 * probably present.
661 *
662 * On entry val should point to a value indicating the APM driver
663 * version with the high byte being the major and the low byte the
664 * minor number both in BCD
665 *
666 * On return it will hold the BIOS revision supported in the
667 * same format.
668 */
669
670static int apm_driver_version(u_short *val)
671{
672 u32 eax;
673
674 if (apm_bios_call_simple(APM_FUNC_VERSION, 0, *val, &eax))
675 return (eax >> 8) & 0xff;
676 *val = eax;
677 return APM_SUCCESS;
678}
679
680/**
681 * apm_get_event - get an APM event from the BIOS
682 * @event: pointer to the event
683 * @info: point to the event information
684 *
685 * The APM BIOS provides a polled information for event
686 * reporting. The BIOS expects to be polled at least every second
687 * when events are pending. When a message is found the caller should
688 * poll until no more messages are present. However, this causes
689 * problems on some laptops where a suspend event notification is
690 * not cleared until it is acknowledged.
691 *
692 * Additional information is returned in the info pointer, providing
693 * that APM 1.2 is in use. If no messges are pending the value 0x80
694 * is returned (No power management events pending).
695 */
696
697static int apm_get_event(apm_event_t *event, apm_eventinfo_t *info)
698{
699 u32 eax;
700 u32 ebx;
701 u32 ecx;
702 u32 dummy;
703
704 if (apm_bios_call(APM_FUNC_GET_EVENT, 0, 0, &eax, &ebx, &ecx,
705 &dummy, &dummy))
706 return (eax >> 8) & 0xff;
707 *event = ebx;
708 if (apm_info.connection_version < 0x0102)
709 *info = ~0; /* indicate info not valid */
710 else
711 *info = ecx;
712 return APM_SUCCESS;
713}
714
715/**
716 * set_power_state - set the power management state
717 * @what: which items to transition
718 * @state: state to transition to
719 *
720 * Request an APM change of state for one or more system devices. The
721 * processor state must be transitioned last of all. what holds the
722 * class of device in the upper byte and the device number (0xFF for
723 * all) for the object to be transitioned.
724 *
725 * The state holds the state to transition to, which may in fact
726 * be an acceptance of a BIOS requested state change.
727 */
728
729static int set_power_state(u_short what, u_short state)
730{
731 u32 eax;
732
733 if (apm_bios_call_simple(APM_FUNC_SET_STATE, what, state, &eax))
734 return (eax >> 8) & 0xff;
735 return APM_SUCCESS;
736}
737
738/**
739 * set_system_power_state - set system wide power state
740 * @state: which state to enter
741 *
742 * Transition the entire system into a new APM power state.
743 */
744
745static int set_system_power_state(u_short state)
746{
747 return set_power_state(APM_DEVICE_ALL, state);
748}
749
750/**
751 * apm_do_idle - perform power saving
752 *
753 * This function notifies the BIOS that the processor is (in the view
754 * of the OS) idle. It returns -1 in the event that the BIOS refuses
755 * to handle the idle request. On a success the function returns 1
756 * if the BIOS did clock slowing or 0 otherwise.
757 */
758
759static int apm_do_idle(void)
760{
761 u32 eax;
64c7c8f8
NP		 762 u8 ret = 0;
763 int idled = 0;
764 int polling;
765
495ab9c0 766 polling = !!(current_thread_info()->status & TS_POLLING);
64c7c8f8 767 if (polling) {
495ab9c0 768 current_thread_info()->status &= ~TS_POLLING;
64c7c8f8
NP		 769 smp_mb__after_clear_bit();
770 }
771 if (!need_resched()) {
772 idled = 1;
773 ret = apm_bios_call_simple(APM_FUNC_IDLE, 0, 0, &eax);
774 }
775 if (polling)
495ab9c0 776 current_thread_info()->status |= TS_POLLING;
64c7c8f8
NP		 777
778 if (!idled)
779 return 0;
780
781 if (ret) {
1da177e4
LT		 782 static unsigned long t;
783
784 /* This always fails on some SMP boards running UP kernels.
785 * Only report the failure the first 5 times.
786 */
787 if (++t < 5)
788 {
789 printk(KERN_DEBUG "apm_do_idle failed (%d)\n",
790 (eax >> 8) & 0xff);
791 t = jiffies;
792 }
793 return -1;
794 }
795 clock_slowed = (apm_info.bios.flags & APM_IDLE_SLOWS_CLOCK) != 0;
796 return clock_slowed;
797}
798
799/**
800 * apm_do_busy - inform the BIOS the CPU is busy
801 *
802 * Request that the BIOS brings the CPU back to full performance.
803 */
804
805static void apm_do_busy(void)
806{
807 u32 dummy;
808
809 if (clock_slowed || ALWAYS_CALL_BUSY) {
810 (void) apm_bios_call_simple(APM_FUNC_BUSY, 0, 0, &dummy);
811 clock_slowed = 0;
812 }
813}
814
815/*
816 * If no process has really been interested in
817 * the CPU for some time, we want to call BIOS
818 * power management - we probably want
819 * to conserve power.
820 */
821#define IDLE_CALC_LIMIT (HZ * 100)
822#define IDLE_LEAKY_MAX 16
823
87af2ffd 824static void (*original_pm_idle)(void) __read_mostly;
1da177e4 825
1da177e4
LT		 826/**
827 * apm_cpu_idle - cpu idling for APM capable Linux
828 *
829 * This is the idling function the kernel executes when APM is available. It
830 * tries to do BIOS powermanagement based on the average system idle time.
831 * Furthermore it calls the system default idle routine.
832 */
833
834static void apm_cpu_idle(void)
835{
836 static int use_apm_idle; /* = 0 */
837 static unsigned int last_jiffies; /* = 0 */
838 static unsigned int last_stime; /* = 0 */
839
840 int apm_idle_done = 0;
841 unsigned int jiffies_since_last_check = jiffies - last_jiffies;
842 unsigned int bucket;
843
844recalc:
845 if (jiffies_since_last_check > IDLE_CALC_LIMIT) {
846 use_apm_idle = 0;
847 last_jiffies = jiffies;
848 last_stime = current->stime;
849 } else if (jiffies_since_last_check > idle_period) {
850 unsigned int idle_percentage;
851
852 idle_percentage = current->stime - last_stime;
853 idle_percentage *= 100;
854 idle_percentage /= jiffies_since_last_check;
855 use_apm_idle = (idle_percentage > idle_threshold);
856 if (apm_info.forbid_idle)
857 use_apm_idle = 0;
858 last_jiffies = jiffies;
859 last_stime = current->stime;
860 }
861
862 bucket = IDLE_LEAKY_MAX;
863
864 while (!need_resched()) {
865 if (use_apm_idle) {
866 unsigned int t;
867
868 t = jiffies;
869 switch (apm_do_idle()) {
870 case 0: apm_idle_done = 1;
871 if (t != jiffies) {
872 if (bucket) {
873 bucket = IDLE_LEAKY_MAX;
874 continue;
875 }
876 } else if (bucket) {
877 bucket--;
878 continue;
879 }
880 break;
881 case 1: apm_idle_done = 1;
882 break;
883 default: /* BIOS refused */
884 break;
885 }
886 }
887 if (original_pm_idle)
888 original_pm_idle();
889 else
890 default_idle();
891 jiffies_since_last_check = jiffies - last_jiffies;
892 if (jiffies_since_last_check > idle_period)
893 goto recalc;
894 }
895
896 if (apm_idle_done)
897 apm_do_busy();
898}
899
900/**
901 * apm_power_off - ask the BIOS to power off
902 *
903 * Handle the power off sequence. This is the one piece of code we
904 * will execute even on SMP machines. In order to deal with BIOS
905 * bugs we support real mode APM BIOS power off calls. We also make
906 * the SMP call on CPU0 as some systems will only honour this call
907 * on their first cpu.
908 */
909
910static void apm_power_off(void)
911{
912 unsigned char po_bios_call[] = {
913 0xb8, 0x00, 0x10, /* movw $0x1000,ax */
914 0x8e, 0xd0, /* movw ax,ss */
915 0xbc, 0x00, 0xf0, /* movw $0xf000,sp */
916 0xb8, 0x07, 0x53, /* movw $0x5307,ax */
917 0xbb, 0x01, 0x00, /* movw $0x0001,bx */
918 0xb9, 0x03, 0x00, /* movw $0x0003,cx */
919 0xcd, 0x15 /* int $0x15 */
920 };
921
1da177e4 922 /* Some bioses don't like being called from CPU != 0 */
1da177e4
LT		 923 if (apm_info.realmode_power_off)
924 {
925 (void)apm_save_cpus();
926 machine_real_restart(po_bios_call, sizeof(po_bios_call));
927 }
928 else
929 (void) set_system_power_state(APM_STATE_OFF);
930}
931
932#ifdef CONFIG_APM_DO_ENABLE
933
934/**
935 * apm_enable_power_management - enable BIOS APM power management
936 * @enable: enable yes/no
937 *
938 * Enable or disable the APM BIOS power services.
939 */
940
941static int apm_enable_power_management(int enable)
942{
943 u32 eax;
944
945 if ((enable == 0) && (apm_info.bios.flags & APM_BIOS_DISENGAGED))
946 return APM_NOT_ENGAGED;
947 if (apm_bios_call_simple(APM_FUNC_ENABLE_PM, APM_DEVICE_BALL,
948 enable, &eax))
949 return (eax >> 8) & 0xff;
950 if (enable)
951 apm_info.bios.flags &= ~APM_BIOS_DISABLED;
952 else
953 apm_info.bios.flags |= APM_BIOS_DISABLED;
954 return APM_SUCCESS;
955}
956#endif
957
958/**
959 * apm_get_power_status - get current power state
960 * @status: returned status
961 * @bat: battery info
962 * @life: estimated life
963 *
964 * Obtain the current power status from the APM BIOS. We return a
965 * status which gives the rough battery status, and current power
966 * source. The bat value returned give an estimate as a percentage
967 * of life and a status value for the battery. The estimated life
968 * if reported is a lifetime in secodnds/minutes at current powwer
969 * consumption.
970 */
971
972static int apm_get_power_status(u_short *status, u_short *bat, u_short *life)
973{
974 u32 eax;
975 u32 ebx;
976 u32 ecx;
977 u32 edx;
978 u32 dummy;
979
980 if (apm_info.get_power_status_broken)
981 return APM_32_UNSUPPORTED;
982 if (apm_bios_call(APM_FUNC_GET_STATUS, APM_DEVICE_ALL, 0,
983 &eax, &ebx, &ecx, &edx, &dummy))
984 return (eax >> 8) & 0xff;
985 *status = ebx;
986 *bat = ecx;
987 if (apm_info.get_power_status_swabinminutes) {
988 *life = swab16((u16)edx);
989 *life |= 0x8000;
990 } else
991 *life = edx;
992 return APM_SUCCESS;
993}
994
995#if 0
996static int apm_get_battery_status(u_short which, u_short *status,
997 u_short *bat, u_short *life, u_short *nbat)
998{
999 u32 eax;
1000 u32 ebx;
1001 u32 ecx;
1002 u32 edx;
1003 u32 esi;
1004
1005 if (apm_info.connection_version < 0x0102) {
1006 /* pretend we only have one battery. */
1007 if (which != 1)
1008 return APM_BAD_DEVICE;
1009 *nbat = 1;
1010 return apm_get_power_status(status, bat, life);
1011 }
1012
1013 if (apm_bios_call(APM_FUNC_GET_STATUS, (0x8000 | (which)), 0, &eax,
1014 &ebx, &ecx, &edx, &esi))
1015 return (eax >> 8) & 0xff;
1016 *status = ebx;
1017 *bat = ecx;
1018 *life = edx;
1019 *nbat = esi;
1020 return APM_SUCCESS;
1021}
1022#endif
1023
1024/**
1025 * apm_engage_power_management - enable PM on a device
1026 * @device: identity of device
1027 * @enable: on/off
1028 *
1029 * Activate or deactive power management on either a specific device
1030 * or the entire system (%APM_DEVICE_ALL).
1031 */
1032
1033static int apm_engage_power_management(u_short device, int enable)
1034{
1035 u32 eax;
1036
1037 if ((enable == 0) && (device == APM_DEVICE_ALL)
1038 && (apm_info.bios.flags & APM_BIOS_DISABLED))
1039 return APM_DISABLED;
1040 if (apm_bios_call_simple(APM_FUNC_ENGAGE_PM, device, enable, &eax))
1041 return (eax >> 8) & 0xff;
1042 if (device == APM_DEVICE_ALL) {
1043 if (enable)
1044 apm_info.bios.flags &= ~APM_BIOS_DISENGAGED;
1045 else
1046 apm_info.bios.flags |= APM_BIOS_DISENGAGED;
1047 }
1048 return APM_SUCCESS;
1049}
1050
1051#if defined(CONFIG_APM_DISPLAY_BLANK) && defined(CONFIG_VT)
1052
1053/**
1054 * apm_console_blank - blank the display
1055 * @blank: on/off
1056 *
1057 * Attempt to blank the console, firstly by blanking just video device
1058 * zero, and if that fails (some BIOSes don't support it) then it blanks
1059 * all video devices. Typically the BIOS will do laptop backlight and
1060 * monitor powerdown for us.
1061 */
1062
1063static int apm_console_blank(int blank)
1064{
87af2ffd
AM		 1065 int error = APM_NOT_ENGAGED; /* silence gcc */
1066 int i;
3841b0a1
JC		 1067 u_short state;
1068 static const u_short dev[3] = { 0x100, 0x1FF, 0x101 };
1da177e4
LT		 1069
1070 state = blank ? APM_STATE_STANDBY : APM_STATE_READY;
3841b0a1
JC		 1071
1072 for (i = 0; i < ARRAY_SIZE(dev); i++) {
1073 error = set_power_state(dev[i], state);
1074
1075 if ((error == APM_SUCCESS) || (error == APM_NO_ERROR))
1076 return 1;
1077
1078 if (error == APM_NOT_ENGAGED)
1079 break;
1da177e4 1080 }
3841b0a1 1081
73374454 1082 if (error == APM_NOT_ENGAGED) {
1da177e4
LT		 1083 static int tried;
1084 int eng_error;
1085 if (tried++ == 0) {
1086 eng_error = apm_engage_power_management(APM_DEVICE_ALL, 1);
1087 if (eng_error) {
1088 apm_error("set display", error);
1089 apm_error("engage interface", eng_error);
1090 return 0;
1091 } else
1092 return apm_console_blank(blank);
1093 }
1094 }
1095 apm_error("set display", error);
1096 return 0;
1097}
1098#endif
1099
1100static int queue_empty(struct apm_user *as)
1101{
1102 return as->event_head == as->event_tail;
1103}
1104
1105static apm_event_t get_queued_event(struct apm_user *as)
1106{
87af2ffd
AM		 1107 if (++as->event_tail >= APM_MAX_EVENTS)
1108 as->event_tail = 0;
1da177e4
LT		 1109 return as->events[as->event_tail];
1110}
1111
1112static void queue_event(apm_event_t event, struct apm_user *sender)
1113{
1114 struct apm_user * as;
1115
1116 spin_lock(&user_list_lock);
1117 if (user_list == NULL)
1118 goto out;
1119 for (as = user_list; as != NULL; as = as->next) {
1120 if ((as == sender) || (!as->reader))
1121 continue;
87af2ffd
AM		 1122 if (++as->event_head >= APM_MAX_EVENTS)
1123 as->event_head = 0;
1124
1da177e4
LT		 1125 if (as->event_head == as->event_tail) {
1126 static int notified;
1127
1128 if (notified++ == 0)
1129 printk(KERN_ERR "apm: an event queue overflowed\n");
87af2ffd
AM		 1130 if (++as->event_tail >= APM_MAX_EVENTS)
1131 as->event_tail = 0;
1da177e4
LT		 1132 }
1133 as->events[as->event_head] = event;
1134 if ((!as->suser) || (!as->writer))
1135 continue;
1136 switch (event) {
1137 case APM_SYS_SUSPEND:
1138 case APM_USER_SUSPEND:
1139 as->suspends_pending++;
1140 suspends_pending++;
1141 break;
1142
1143 case APM_SYS_STANDBY:
1144 case APM_USER_STANDBY:
1145 as->standbys_pending++;
1146 standbys_pending++;
1147 break;
1148 }
1149 }
1150 wake_up_interruptible(&apm_waitqueue);
1151out:
1152 spin_unlock(&user_list_lock);
1153}
1154
1155static void set_time(void)
1156{
1157 if (got_clock_diff) { /* Must know time zone in order to set clock */
1158 xtime.tv_sec = get_cmos_time() + clock_cmos_diff;
1159 xtime.tv_nsec = 0;
1160 }
1161}
1162
1163static void get_time_diff(void)
1164{
1165#ifndef CONFIG_APM_RTC_IS_GMT
1166 /*
1167 * Estimate time zone so that set_time can update the clock
1168 */
1169 clock_cmos_diff = -get_cmos_time();
1170 clock_cmos_diff += get_seconds();
1171 got_clock_diff = 1;
1172#endif
1173}
1174
1175static void reinit_timer(void)
1176{
1177#ifdef INIT_TIMER_AFTER_SUSPEND
306e440d 1178 unsigned long flags;
1da177e4
LT		 1179
1180 spin_lock_irqsave(&i8253_lock, flags);
1181 /* set the clock to 100 Hz */
1182 outb_p(0x34, PIT_MODE); /* binary, mode 2, LSB/MSB, ch 0 */
1183 udelay(10);
1184 outb_p(LATCH & 0xff, PIT_CH0); /* LSB */
1185 udelay(10);
1186 outb(LATCH >> 8, PIT_CH0); /* MSB */
1187 udelay(10);
1188 spin_unlock_irqrestore(&i8253_lock, flags);
1189#endif
1190}
1191
1192static int suspend(int vetoable)
1193{
1194 int err;
1195 struct apm_user *as;
1196
1197 if (pm_send_all(PM_SUSPEND, (void *)3)) {
1198 /* Vetoed */
1199 if (vetoable) {
1200 if (apm_info.connection_version > 0x100)
1201 set_system_power_state(APM_STATE_REJECT);
1202 err = -EBUSY;
1203 ignore_sys_suspend = 0;
1204 printk(KERN_WARNING "apm: suspend was vetoed.\n");
1205 goto out;
1206 }
1207 printk(KERN_CRIT "apm: suspend was vetoed, but suspending anyway.\n");
1208 }
1209
1210 device_suspend(PMSG_SUSPEND);
1211 local_irq_disable();
1212 device_power_down(PMSG_SUSPEND);
1213
1214 /* serialize with the timer interrupt */
1215 write_seqlock(&xtime_lock);
1216
1217 /* protect against access to timer chip registers */
1218 spin_lock(&i8253_lock);
1219
1220 get_time_diff();
1221 /*
1222 * Irq spinlock must be dropped around set_system_power_state.
1223 * We'll undo any timer changes due to interrupts below.
1224 */
1225 spin_unlock(&i8253_lock);
1226 write_sequnlock(&xtime_lock);
1227 local_irq_enable();
1228
1229 save_processor_state();
1230 err = set_system_power_state(APM_STATE_SUSPEND);
92c6dc59 1231 ignore_normal_resume = 1;
1da177e4
LT		 1232 restore_processor_state();
1233
1234 local_irq_disable();
1235 write_seqlock(&xtime_lock);
1236 spin_lock(&i8253_lock);
1237 reinit_timer();
1238 set_time();
1da177e4
LT		 1239
1240 spin_unlock(&i8253_lock);
1241 write_sequnlock(&xtime_lock);
1242
1243 if (err == APM_NO_ERROR)
1244 err = APM_SUCCESS;
1245 if (err != APM_SUCCESS)
1246 apm_error("suspend", err);
1247 err = (err == APM_SUCCESS) ? 0 : -EIO;
1248 device_power_up();
1249 local_irq_enable();
1250 device_resume();
1251 pm_send_all(PM_RESUME, (void *)0);
1252 queue_event(APM_NORMAL_RESUME, NULL);
1253 out:
1254 spin_lock(&user_list_lock);
1255 for (as = user_list; as != NULL; as = as->next) {
1256 as->suspend_wait = 0;
1257 as->suspend_result = err;
1258 }
1259 spin_unlock(&user_list_lock);
1260 wake_up_interruptible(&apm_suspend_waitqueue);
1261 return err;
1262}
1263
1264static void standby(void)
1265{
1266 int err;
1267
1268 local_irq_disable();
1269 device_power_down(PMSG_SUSPEND);
1270 /* serialize with the timer interrupt */
1271 write_seqlock(&xtime_lock);
1272 /* If needed, notify drivers here */
1273 get_time_diff();
1274 write_sequnlock(&xtime_lock);
1275 local_irq_enable();
1276
1277 err = set_system_power_state(APM_STATE_STANDBY);
1278 if ((err != APM_SUCCESS) && (err != APM_NO_ERROR))
1279 apm_error("standby", err);
1280
1281 local_irq_disable();
1282 device_power_up();
1283 local_irq_enable();
1284}
1285
1286static apm_event_t get_event(void)
1287{
1288 int error;
87af2ffd 1289 apm_event_t event = APM_NO_EVENTS; /* silence gcc */
1da177e4
LT		 1290 apm_eventinfo_t info;
1291
1292 static int notified;
1293
1294 /* we don't use the eventinfo */
1295 error = apm_get_event(&event, &info);
1296 if (error == APM_SUCCESS)
1297 return event;
1298
1299 if ((error != APM_NO_EVENTS) && (notified++ == 0))
1300 apm_error("get_event", error);
1301
1302 return 0;
1303}
1304
1305static void check_events(void)
1306{
1307 apm_event_t event;
1308 static unsigned long last_resume;
1309 static int ignore_bounce;
1310
1311 while ((event = get_event()) != 0) {
1312 if (debug) {
1313 if (event <= NR_APM_EVENT_NAME)
1314 printk(KERN_DEBUG "apm: received %s notify\n",
1315 apm_event_name[event - 1]);
1316 else
1317 printk(KERN_DEBUG "apm: received unknown "
1318 "event 0x%02x\n", event);
1319 }
1320 if (ignore_bounce
1321 && ((jiffies - last_resume) > bounce_interval))
1322 ignore_bounce = 0;
1323
1324 switch (event) {
1325 case APM_SYS_STANDBY:
1326 case APM_USER_STANDBY:
1327 queue_event(event, NULL);
1328 if (standbys_pending <= 0)
1329 standby();
1330 break;
1331
1332 case APM_USER_SUSPEND:
1333#ifdef CONFIG_APM_IGNORE_USER_SUSPEND
1334 if (apm_info.connection_version > 0x100)
1335 set_system_power_state(APM_STATE_REJECT);
1336 break;
1337#endif
1338 case APM_SYS_SUSPEND:
1339 if (ignore_bounce) {
1340 if (apm_info.connection_version > 0x100)
1341 set_system_power_state(APM_STATE_REJECT);
1342 break;
1343 }
1344 /*
1345 * If we are already processing a SUSPEND,
1346 * then further SUSPEND events from the BIOS
1347 * will be ignored. We also return here to
1348 * cope with the fact that the Thinkpads keep
1349 * sending a SUSPEND event until something else
1350 * happens!
1351 */
1352 if (ignore_sys_suspend)
1353 return;
1354 ignore_sys_suspend = 1;
1355 queue_event(event, NULL);
1356 if (suspends_pending <= 0)
1357 (void) suspend(1);
1358 break;
1359
1360 case APM_NORMAL_RESUME:
1361 case APM_CRITICAL_RESUME:
1362 case APM_STANDBY_RESUME:
1363 ignore_sys_suspend = 0;
1364 last_resume = jiffies;
1365 ignore_bounce = 1;
1366 if ((event != APM_NORMAL_RESUME)
1367 || (ignore_normal_resume == 0)) {
1368 write_seqlock_irq(&xtime_lock);
1369 set_time();
1370 write_sequnlock_irq(&xtime_lock);
1371 device_resume();
1372 pm_send_all(PM_RESUME, (void *)0);
1373 queue_event(event, NULL);
1374 }
1375 ignore_normal_resume = 0;
1376 break;
1377
1378 case APM_CAPABILITY_CHANGE:
1379 case APM_LOW_BATTERY:
1380 case APM_POWER_STATUS_CHANGE:
1381 queue_event(event, NULL);
1382 /* If needed, notify drivers here */
1383 break;
1384
1385 case APM_UPDATE_TIME:
1386 write_seqlock_irq(&xtime_lock);
1387 set_time();
1388 write_sequnlock_irq(&xtime_lock);
1389 break;
1390
1391 case APM_CRITICAL_SUSPEND:
1392 /*
1393 * We are not allowed to reject a critical suspend.
1394 */
1395 (void) suspend(0);
1396 break;
1397 }
1398 }
1399}
1400
1401static void apm_event_handler(void)
1402{
1403 static int pending_count = 4;
1404 int err;
1405
1406 if ((standbys_pending > 0) || (suspends_pending > 0)) {
1407 if ((apm_info.connection_version > 0x100) &&
1408 (pending_count-- <= 0)) {
1409 pending_count = 4;
1410 if (debug)
1411 printk(KERN_DEBUG "apm: setting state busy\n");
1412 err = set_system_power_state(APM_STATE_BUSY);
1413 if (err)
1414 apm_error("busy", err);
1415 }
1416 } else
1417 pending_count = 4;
1418 check_events();
1419}
1420
1421/*
1422 * This is the APM thread main loop.
1423 */
1424
1425static void apm_mainloop(void)
1426{
1427 DECLARE_WAITQUEUE(wait, current);
1428
1429 add_wait_queue(&apm_waitqueue, &wait);
1430 set_current_state(TASK_INTERRUPTIBLE);
1431 for (;;) {
1432 schedule_timeout(APM_CHECK_TIMEOUT);
1433 if (exit_kapmd)
1434 break;
1435 /*
1436 * Ok, check all events, check for idle (and mark us sleeping
1437 * so as not to count towards the load average)..
1438 */
1439 set_current_state(TASK_INTERRUPTIBLE);
1440 apm_event_handler();
1441 }
1442 remove_wait_queue(&apm_waitqueue, &wait);
1443}
1444
1445static int check_apm_user(struct apm_user *as, const char *func)
1446{
1447 if ((as == NULL) || (as->magic != APM_BIOS_MAGIC)) {
1448 printk(KERN_ERR "apm: %s passed bad filp\n", func);
1449 return 1;
1450 }
1451 return 0;
1452}
1453
1454static ssize_t do_read(struct file *fp, char __user *buf, size_t count, loff_t *ppos)
1455{
1456 struct apm_user * as;
1457 int i;
1458 apm_event_t event;
1459
1460 as = fp->private_data;
1461 if (check_apm_user(as, "read"))
1462 return -EIO;
1463 if ((int)count < sizeof(apm_event_t))
1464 return -EINVAL;
1465 if ((queue_empty(as)) && (fp->f_flags & O_NONBLOCK))
1466 return -EAGAIN;
1467 wait_event_interruptible(apm_waitqueue, !queue_empty(as));
1468 i = count;
1469 while ((i >= sizeof(event)) && !queue_empty(as)) {
1470 event = get_queued_event(as);
1471 if (copy_to_user(buf, &event, sizeof(event))) {
1472 if (i < count)
1473 break;
1474 return -EFAULT;
1475 }
1476 switch (event) {
1477 case APM_SYS_SUSPEND:
1478 case APM_USER_SUSPEND:
1479 as->suspends_read++;
1480 break;
1481
1482 case APM_SYS_STANDBY:
1483 case APM_USER_STANDBY:
1484 as->standbys_read++;
1485 break;
1486 }
1487 buf += sizeof(event);
1488 i -= sizeof(event);
1489 }
1490 if (i < count)
1491 return count - i;
1492 if (signal_pending(current))
1493 return -ERESTARTSYS;
1494 return 0;
1495}
1496
1497static unsigned int do_poll(struct file *fp, poll_table * wait)
1498{
1499 struct apm_user * as;
1500
1501 as = fp->private_data;
1502 if (check_apm_user(as, "poll"))
1503 return 0;
1504 poll_wait(fp, &apm_waitqueue, wait);
1505 if (!queue_empty(as))
1506 return POLLIN | POLLRDNORM;
1507 return 0;
1508}
1509
1510static int do_ioctl(struct inode * inode, struct file *filp,
1511 u_int cmd, u_long arg)
1512{
1513 struct apm_user * as;
1514
1515 as = filp->private_data;
1516 if (check_apm_user(as, "ioctl"))
1517 return -EIO;
1518 if ((!as->suser) || (!as->writer))
1519 return -EPERM;
1520 switch (cmd) {
1521 case APM_IOC_STANDBY:
1522 if (as->standbys_read > 0) {
1523 as->standbys_read--;
1524 as->standbys_pending--;
1525 standbys_pending--;
1526 } else
1527 queue_event(APM_USER_STANDBY, as);
1528 if (standbys_pending <= 0)
1529 standby();
1530 break;
1531 case APM_IOC_SUSPEND:
1532 if (as->suspends_read > 0) {
1533 as->suspends_read--;
1534 as->suspends_pending--;
1535 suspends_pending--;
1536 } else
1537 queue_event(APM_USER_SUSPEND, as);
1538 if (suspends_pending <= 0) {
1539 return suspend(1);
1540 } else {
1541 as->suspend_wait = 1;
1542 wait_event_interruptible(apm_suspend_waitqueue,
1543 as->suspend_wait == 0);
1544 return as->suspend_result;
1545 }
1546 break;
1547 default:
1548 return -EINVAL;
1549 }
1550 return 0;
1551}
1552
1553static int do_release(struct inode * inode, struct file * filp)
1554{
1555 struct apm_user * as;
1556
1557 as = filp->private_data;
1558 if (check_apm_user(as, "release"))
1559 return 0;
1560 filp->private_data = NULL;
1561 if (as->standbys_pending > 0) {
1562 standbys_pending -= as->standbys_pending;
1563 if (standbys_pending <= 0)
1564 standby();
1565 }
1566 if (as->suspends_pending > 0) {
1567 suspends_pending -= as->suspends_pending;
1568 if (suspends_pending <= 0)
1569 (void) suspend(1);
1570 }
1571 spin_lock(&user_list_lock);
1572 if (user_list == as)
1573 user_list = as->next;
1574 else {
1575 struct apm_user * as1;
1576
1577 for (as1 = user_list;
1578 (as1 != NULL) && (as1->next != as);
1579 as1 = as1->next)
1580 ;
1581 if (as1 == NULL)
1582 printk(KERN_ERR "apm: filp not in user list\n");
1583 else
1584 as1->next = as->next;
1585 }
1586 spin_unlock(&user_list_lock);
1587 kfree(as);
1588 return 0;
1589}
1590
1591static int do_open(struct inode * inode, struct file * filp)
1592{
1593 struct apm_user * as;
1594
1595 as = (struct apm_user *)kmalloc(sizeof(*as), GFP_KERNEL);
1596 if (as == NULL) {
1597 printk(KERN_ERR "apm: cannot allocate struct of size %d bytes\n",
1598 sizeof(*as));
1599 return -ENOMEM;
1600 }
1601 as->magic = APM_BIOS_MAGIC;
1602 as->event_tail = as->event_head = 0;
1603 as->suspends_pending = as->standbys_pending = 0;
1604 as->suspends_read = as->standbys_read = 0;
1605 /*
1606 * XXX - this is a tiny bit broken, when we consider BSD
1607 * process accounting. If the device is opened by root, we
1608 * instantly flag that we used superuser privs. Who knows,
1609 * we might close the device immediately without doing a
1610 * privileged operation -- cevans
1611 */
1612 as->suser = capable(CAP_SYS_ADMIN);
1613 as->writer = (filp->f_mode & FMODE_WRITE) == FMODE_WRITE;
1614 as->reader = (filp->f_mode & FMODE_READ) == FMODE_READ;
1615 spin_lock(&user_list_lock);
1616 as->next = user_list;
1617 user_list = as;
1618 spin_unlock(&user_list_lock);
1619 filp->private_data = as;
1620 return 0;
1621}
1622
1623static int apm_get_info(char *buf, char **start, off_t fpos, int length)
1624{
1625 char * p;
1626 unsigned short bx;
1627 unsigned short cx;
1628 unsigned short dx;
1629 int error;
1630 unsigned short ac_line_status = 0xff;
1631 unsigned short battery_status = 0xff;
1632 unsigned short battery_flag = 0xff;
1633 int percentage = -1;
1634 int time_units = -1;
1635 char *units = "?";
1636
1637 p = buf;
1638
1639 if ((num_online_cpus() == 1) &&
1640 !(error = apm_get_power_status(&bx, &cx, &dx))) {
1641 ac_line_status = (bx >> 8) & 0xff;
1642 battery_status = bx & 0xff;
1643 if ((cx & 0xff) != 0xff)
1644 percentage = cx & 0xff;
1645
1646 if (apm_info.connection_version > 0x100) {
1647 battery_flag = (cx >> 8) & 0xff;
1648 if (dx != 0xffff) {
1649 units = (dx & 0x8000) ? "min" : "sec";
1650 time_units = dx & 0x7fff;
1651 }
1652 }
1653 }
1654 /* Arguments, with symbols from linux/apm_bios.h. Information is
1655 from the Get Power Status (0x0a) call unless otherwise noted.
1656
1657 0) Linux driver version (this will change if format changes)
1658 1) APM BIOS Version. Usually 1.0, 1.1 or 1.2.
1659 2) APM flags from APM Installation Check (0x00):
1660 bit 0: APM_16_BIT_SUPPORT
1661 bit 1: APM_32_BIT_SUPPORT
1662 bit 2: APM_IDLE_SLOWS_CLOCK
1663 bit 3: APM_BIOS_DISABLED
1664 bit 4: APM_BIOS_DISENGAGED
1665 3) AC line status
1666 0x00: Off-line
1667 0x01: On-line
1668 0x02: On backup power (BIOS >= 1.1 only)
1669 0xff: Unknown
1670 4) Battery status
1671 0x00: High
1672 0x01: Low
1673 0x02: Critical
1674 0x03: Charging
1675 0x04: Selected battery not present (BIOS >= 1.2 only)
1676 0xff: Unknown
1677 5) Battery flag
1678 bit 0: High
1679 bit 1: Low
1680 bit 2: Critical
1681 bit 3: Charging
1682 bit 7: No system battery
1683 0xff: Unknown
1684 6) Remaining battery life (percentage of charge):
1685 0-100: valid
1686 -1: Unknown
1687 7) Remaining battery life (time units):
1688 Number of remaining minutes or seconds
1689 -1: Unknown
1690 8) min = minutes; sec = seconds */
1691
1692 p += sprintf(p, "%s %d.%d 0x%02x 0x%02x 0x%02x 0x%02x %d%% %d %s\n",
1693 driver_version,
1694 (apm_info.bios.version >> 8) & 0xff,
1695 apm_info.bios.version & 0xff,
1696 apm_info.bios.flags,
1697 ac_line_status,
1698 battery_status,
1699 battery_flag,
1700 percentage,
1701 time_units,
1702 units);
1703
1704 return p - buf;
1705}
1706
1707static int apm(void *unused)
1708{
1709 unsigned short bx;
1710 unsigned short cx;
1711 unsigned short dx;
1712 int error;
1713 char * power_stat;
1714 char * bat_stat;
1715
1716 kapmd_running = 1;
1717
1718 daemonize("kapmd");
1719
1720 current->flags |= PF_NOFREEZE;
1721
1722#ifdef CONFIG_SMP
1723 /* 2002/08/01 - WT
1724 * This is to avoid random crashes at boot time during initialization
1725 * on SMP systems in case of "apm=power-off" mode. Seen on ASUS A7M266D.
1726 * Some bioses don't like being called from CPU != 0.
1727 * Method suggested by Ingo Molnar.
1728 */
1729 set_cpus_allowed(current, cpumask_of_cpu(0));
1730 BUG_ON(smp_processor_id() != 0);
1731#endif
1732
1733 if (apm_info.connection_version == 0) {
1734 apm_info.connection_version = apm_info.bios.version;
1735 if (apm_info.connection_version > 0x100) {
1736 /*
1737 * We only support BIOSs up to version 1.2
1738 */
1739 if (apm_info.connection_version > 0x0102)
1740 apm_info.connection_version = 0x0102;
1741 error = apm_driver_version(&apm_info.connection_version);
1742 if (error != APM_SUCCESS) {
1743 apm_error("driver version", error);
1744 /* Fall back to an APM 1.0 connection. */
1745 apm_info.connection_version = 0x100;
1746 }
1747 }
1748 }
1749
1750 if (debug)
1751 printk(KERN_INFO "apm: Connection version %d.%d\n",
1752 (apm_info.connection_version >> 8) & 0xff,
1753 apm_info.connection_version & 0xff);
1754
1755#ifdef CONFIG_APM_DO_ENABLE
1756 if (apm_info.bios.flags & APM_BIOS_DISABLED) {
1757 /*
1758 * This call causes my NEC UltraLite Versa 33/C to hang if it
1759 * is booted with PM disabled but not in the docking station.
1760 * Unfortunate ...
1761 */
1762 error = apm_enable_power_management(1);
1763 if (error) {
1764 apm_error("enable power management", error);
1765 return -1;
1766 }
1767 }
1768#endif
1769
1770 if ((apm_info.bios.flags & APM_BIOS_DISENGAGED)
1771 && (apm_info.connection_version > 0x0100)) {
1772 error = apm_engage_power_management(APM_DEVICE_ALL, 1);
1773 if (error) {
1774 apm_error("engage power management", error);
1775 return -1;
1776 }
1777 }
1778
1779 if (debug && (num_online_cpus() == 1 || smp )) {
1780 error = apm_get_power_status(&bx, &cx, &dx);
1781 if (error)
1782 printk(KERN_INFO "apm: power status not available\n");
1783 else {
1784 switch ((bx >> 8) & 0xff) {
1785 case 0: power_stat = "off line"; break;
1786 case 1: power_stat = "on line"; break;
1787 case 2: power_stat = "on backup power"; break;
1788 default: power_stat = "unknown"; break;
1789 }
1790 switch (bx & 0xff) {
1791 case 0: bat_stat = "high"; break;
1792 case 1: bat_stat = "low"; break;
1793 case 2: bat_stat = "critical"; break;
1794 case 3: bat_stat = "charging"; break;
1795 default: bat_stat = "unknown"; break;
1796 }
1797 printk(KERN_INFO
1798 "apm: AC %s, battery status %s, battery life ",
1799 power_stat, bat_stat);
1800 if ((cx & 0xff) == 0xff)
1801 printk("unknown\n");
1802 else
1803 printk("%d%%\n", cx & 0xff);
1804 if (apm_info.connection_version > 0x100) {
1805 printk(KERN_INFO
1806 "apm: battery flag 0x%02x, battery life ",
1807 (cx >> 8) & 0xff);
1808 if (dx == 0xffff)
1809 printk("unknown\n");
1810 else
1811 printk("%d %s\n", dx & 0x7fff,
1812 (dx & 0x8000) ?
1813 "minutes" : "seconds");
1814 }
1815 }
1816 }
1817
1818 /* Install our power off handler.. */
1819 if (power_off)
1820 pm_power_off = apm_power_off;
1821
1822 if (num_online_cpus() == 1 || smp) {
1823#if defined(CONFIG_APM_DISPLAY_BLANK) && defined(CONFIG_VT)
1824 console_blank_hook = apm_console_blank;
1825#endif
1826 apm_mainloop();
1827#if defined(CONFIG_APM_DISPLAY_BLANK) && defined(CONFIG_VT)
1828 console_blank_hook = NULL;
1829#endif
1830 }
1831 kapmd_running = 0;
1832
1833 return 0;
1834}
1835
1836#ifndef MODULE
1837static int __init apm_setup(char *str)
1838{
1839 int invert;
1840
1841 while ((str != NULL) && (*str != '\0')) {
1842 if (strncmp(str, "off", 3) == 0)
1843 apm_disabled = 1;
1844 if (strncmp(str, "on", 2) == 0)
1845 apm_disabled = 0;
1846 if ((strncmp(str, "bounce-interval=", 16) == 0) ||
1847 (strncmp(str, "bounce_interval=", 16) == 0))
1848 bounce_interval = simple_strtol(str + 16, NULL, 0);
1849 if ((strncmp(str, "idle-threshold=", 15) == 0) ||
1850 (strncmp(str, "idle_threshold=", 15) == 0))
1851 idle_threshold = simple_strtol(str + 15, NULL, 0);
1852 if ((strncmp(str, "idle-period=", 12) == 0) ||
1853 (strncmp(str, "idle_period=", 12) == 0))
1854 idle_period = simple_strtol(str + 12, NULL, 0);
1855 invert = (strncmp(str, "no-", 3) == 0) ||
1856 (strncmp(str, "no_", 3) == 0);
1857 if (invert)
1858 str += 3;
1859 if (strncmp(str, "debug", 5) == 0)
1860 debug = !invert;
1861 if ((strncmp(str, "power-off", 9) == 0) ||
1862 (strncmp(str, "power_off", 9) == 0))
1863 power_off = !invert;
1864 if (strncmp(str, "smp", 3) == 0)
1865 {
1866 smp = !invert;
1867 idle_threshold = 100;
1868 }
1869 if ((strncmp(str, "allow-ints", 10) == 0) ||
1870 (strncmp(str, "allow_ints", 10) == 0))
1871 apm_info.allow_ints = !invert;
1872 if ((strncmp(str, "broken-psr", 10) == 0) ||
1873 (strncmp(str, "broken_psr", 10) == 0))
1874 apm_info.get_power_status_broken = !invert;
1875 if ((strncmp(str, "realmode-power-off", 18) == 0) ||
1876 (strncmp(str, "realmode_power_off", 18) == 0))
1877 apm_info.realmode_power_off = !invert;
1878 str = strchr(str, ',');
1879 if (str != NULL)
1880 str += strspn(str, ", \t");
1881 }
1882 return 1;
1883}
1884
1885__setup("apm=", apm_setup);
1886#endif
1887
1888static struct file_operations apm_bios_fops = {
1889 .owner = THIS_MODULE,
1890 .read = do_read,
1891 .poll = do_poll,
1892 .ioctl = do_ioctl,
1893 .open = do_open,
1894 .release = do_release,
1895};
1896
1897static struct miscdevice apm_device = {
1898 APM_MINOR_DEV,
1899 "apm_bios",
1900 &apm_bios_fops
1901};
1902
1903
1904/* Simple "print if true" callback */
1905static int __init print_if_true(struct dmi_system_id *d)
1906{
1907 printk("%s\n", d->ident);
1908 return 0;
1909}
1910
1911/*
1912 * Some Bioses enable the PS/2 mouse (touchpad) at resume, even if it was
1913 * disabled before the suspend. Linux used to get terribly confused by that.
1914 */
1915static int __init broken_ps2_resume(struct dmi_system_id *d)
1916{
1917 printk(KERN_INFO "%s machine detected. Mousepad Resume Bug workaround hopefully not needed.\n", d->ident);
1918 return 0;
1919}
1920
1921/* Some bioses have a broken protected mode poweroff and need to use realmode */
1922static int __init set_realmode_power_off(struct dmi_system_id *d)
1923{
1924 if (apm_info.realmode_power_off == 0) {
1925 apm_info.realmode_power_off = 1;
1926 printk(KERN_INFO "%s bios detected. Using realmode poweroff only.\n", d->ident);
1927 }
1928 return 0;
1929}
1930
1931/* Some laptops require interrupts to be enabled during APM calls */
1932static int __init set_apm_ints(struct dmi_system_id *d)
1933{
1934 if (apm_info.allow_ints == 0) {
1935 apm_info.allow_ints = 1;
1936 printk(KERN_INFO "%s machine detected. Enabling interrupts during APM calls.\n", d->ident);
1937 }
1938 return 0;
1939}
1940
1941/* Some APM bioses corrupt memory or just plain do not work */
1942static int __init apm_is_horked(struct dmi_system_id *d)
1943{
1944 if (apm_info.disabled == 0) {
1945 apm_info.disabled = 1;
1946 printk(KERN_INFO "%s machine detected. Disabling APM.\n", d->ident);
1947 }
1948 return 0;
1949}
1950
1951static int __init apm_is_horked_d850md(struct dmi_system_id *d)
1952{
1953 if (apm_info.disabled == 0) {
1954 apm_info.disabled = 1;
1955 printk(KERN_INFO "%s machine detected. Disabling APM.\n", d->ident);
1956 printk(KERN_INFO "This bug is fixed in bios P15 which is available for \n");
1957 printk(KERN_INFO "download from support.intel.com \n");
1958 }
1959 return 0;
1960}
1961
1962/* Some APM bioses hang on APM idle calls */
1963static int __init apm_likes_to_melt(struct dmi_system_id *d)
1964{
1965 if (apm_info.forbid_idle == 0) {
1966 apm_info.forbid_idle = 1;
1967 printk(KERN_INFO "%s machine detected. Disabling APM idle calls.\n", d->ident);
1968 }
1969 return 0;
1970}
1971
1972/*
1973 * Check for clue free BIOS implementations who use
1974 * the following QA technique
1975 *
1976 * [ Write BIOS Code ]<------
1977 * | ^
1978 * < Does it Compile >----N--
1979 * |Y ^
1980 * < Does it Boot Win98 >-N--
1981 * |Y
1982 * [Ship It]
1983 *
1984 * Phoenix A04 08/24/2000 is known bad (Dell Inspiron 5000e)
1985 * Phoenix A07 09/29/2000 is known good (Dell Inspiron 5000)
1986 */
1987static int __init broken_apm_power(struct dmi_system_id *d)
1988{
1989 apm_info.get_power_status_broken = 1;
1990 printk(KERN_WARNING "BIOS strings suggest APM bugs, disabling power status reporting.\n");
1991 return 0;
1992}
1993
1994/*
1995 * This bios swaps the APM minute reporting bytes over (Many sony laptops
1996 * have this problem).
1997 */
1998static int __init swab_apm_power_in_minutes(struct dmi_system_id *d)
1999{
2000 apm_info.get_power_status_swabinminutes = 1;
2001 printk(KERN_WARNING "BIOS strings suggest APM reports battery life in minutes and wrong byte order.\n");
2002 return 0;
2003}
2004
2005static struct dmi_system_id __initdata apm_dmi_table[] = {
2006 {
2007 print_if_true,
2008 KERN_WARNING "IBM T23 - BIOS 1.03b+ and controller firmware 1.02+ may be needed for Linux APM.",
2009 { DMI_MATCH(DMI_SYS_VENDOR, "IBM"),
2010 DMI_MATCH(DMI_BIOS_VERSION, "1AET38WW (1.01b)"), },
2011 },
2012 { /* Handle problems with APM on the C600 */
2013 broken_ps2_resume, "Dell Latitude C600",
2014 { DMI_MATCH(DMI_SYS_VENDOR, "Dell"),
2015 DMI_MATCH(DMI_PRODUCT_NAME, "Latitude C600"), },
2016 },
2017 { /* Allow interrupts during suspend on Dell Latitude laptops*/
2018 set_apm_ints, "Dell Latitude",
2019 { DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
2020 DMI_MATCH(DMI_PRODUCT_NAME, "Latitude C510"), }
2021 },
2022 { /* APM crashes */
2023 apm_is_horked, "Dell Inspiron 2500",
2024 { DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
2025 DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 2500"),
2026 DMI_MATCH(DMI_BIOS_VENDOR,"Phoenix Technologies LTD"),
2027 DMI_MATCH(DMI_BIOS_VERSION,"A11"), },
2028 },
2029 { /* Allow interrupts during suspend on Dell Inspiron laptops*/
2030 set_apm_ints, "Dell Inspiron", {
2031 DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
2032 DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 4000"), },
2033 },
2034 { /* Handle problems with APM on Inspiron 5000e */
2035 broken_apm_power, "Dell Inspiron 5000e",
2036 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2037 DMI_MATCH(DMI_BIOS_VERSION, "A04"),
2038 DMI_MATCH(DMI_BIOS_DATE, "08/24/2000"), },
2039 },
2040 { /* Handle problems with APM on Inspiron 2500 */
2041 broken_apm_power, "Dell Inspiron 2500",
2042 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2043 DMI_MATCH(DMI_BIOS_VERSION, "A12"),
2044 DMI_MATCH(DMI_BIOS_DATE, "02/04/2002"), },
2045 },
2046 { /* APM crashes */
2047 apm_is_horked, "Dell Dimension 4100",
2048 { DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
2049 DMI_MATCH(DMI_PRODUCT_NAME, "XPS-Z"),
2050 DMI_MATCH(DMI_BIOS_VENDOR,"Intel Corp."),
2051 DMI_MATCH(DMI_BIOS_VERSION,"A11"), },
2052 },
2053 { /* Allow interrupts during suspend on Compaq Laptops*/
2054 set_apm_ints, "Compaq 12XL125",
2055 { DMI_MATCH(DMI_SYS_VENDOR, "Compaq"),
2056 DMI_MATCH(DMI_PRODUCT_NAME, "Compaq PC"),
2057 DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2058 DMI_MATCH(DMI_BIOS_VERSION,"4.06"), },
2059 },
2060 { /* Allow interrupts during APM or the clock goes slow */
2061 set_apm_ints, "ASUSTeK",
2062 { DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK Computer Inc."),
2063 DMI_MATCH(DMI_PRODUCT_NAME, "L8400K series Notebook PC"), },
2064 },
2065 { /* APM blows on shutdown */
2066 apm_is_horked, "ABIT KX7-333[R]",
2067 { DMI_MATCH(DMI_BOARD_VENDOR, "ABIT"),
2068 DMI_MATCH(DMI_BOARD_NAME, "VT8367-8233A (KX7-333[R])"), },
2069 },
2070 { /* APM crashes */
2071 apm_is_horked, "Trigem Delhi3",
2072 { DMI_MATCH(DMI_SYS_VENDOR, "TriGem Computer, Inc"),
2073 DMI_MATCH(DMI_PRODUCT_NAME, "Delhi3"), },
2074 },
2075 { /* APM crashes */
2076 apm_is_horked, "Fujitsu-Siemens",
2077 { DMI_MATCH(DMI_BIOS_VENDOR, "hoenix/FUJITSU SIEMENS"),
2078 DMI_MATCH(DMI_BIOS_VERSION, "Version1.01"), },
2079 },
2080 { /* APM crashes */
2081 apm_is_horked_d850md, "Intel D850MD",
2082 { DMI_MATCH(DMI_BIOS_VENDOR, "Intel Corp."),
2083 DMI_MATCH(DMI_BIOS_VERSION, "MV85010A.86A.0016.P07.0201251536"), },
2084 },
2085 { /* APM crashes */
2086 apm_is_horked, "Intel D810EMO",
2087 { DMI_MATCH(DMI_BIOS_VENDOR, "Intel Corp."),
2088 DMI_MATCH(DMI_BIOS_VERSION, "MO81010A.86A.0008.P04.0004170800"), },
2089 },
2090 { /* APM crashes */
2091 apm_is_horked, "Dell XPS-Z",
2092 { DMI_MATCH(DMI_BIOS_VENDOR, "Intel Corp."),
2093 DMI_MATCH(DMI_BIOS_VERSION, "A11"),
2094 DMI_MATCH(DMI_PRODUCT_NAME, "XPS-Z"), },
2095 },
2096 { /* APM crashes */
2097 apm_is_horked, "Sharp PC-PJ/AX",
2098 { DMI_MATCH(DMI_SYS_VENDOR, "SHARP"),
2099 DMI_MATCH(DMI_PRODUCT_NAME, "PC-PJ/AX"),
2100 DMI_MATCH(DMI_BIOS_VENDOR,"SystemSoft"),
2101 DMI_MATCH(DMI_BIOS_VERSION,"Version R2.08"), },
2102 },
2103 { /* APM crashes */
2104 apm_is_horked, "Dell Inspiron 2500",
2105 { DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
2106 DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 2500"),
2107 DMI_MATCH(DMI_BIOS_VENDOR,"Phoenix Technologies LTD"),
2108 DMI_MATCH(DMI_BIOS_VERSION,"A11"), },
2109 },
2110 { /* APM idle hangs */
2111 apm_likes_to_melt, "Jabil AMD",
2112 { DMI_MATCH(DMI_BIOS_VENDOR, "American Megatrends Inc."),
2113 DMI_MATCH(DMI_BIOS_VERSION, "0AASNP06"), },
2114 },
2115 { /* APM idle hangs */
2116 apm_likes_to_melt, "AMI Bios",
2117 { DMI_MATCH(DMI_BIOS_VENDOR, "American Megatrends Inc."),
2118 DMI_MATCH(DMI_BIOS_VERSION, "0AASNP05"), },
2119 },
2120 { /* Handle problems with APM on Sony Vaio PCG-N505X(DE) */
2121 swab_apm_power_in_minutes, "Sony VAIO",
2122 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2123 DMI_MATCH(DMI_BIOS_VERSION, "R0206H"),
2124 DMI_MATCH(DMI_BIOS_DATE, "08/23/99"), },
2125 },
2126 { /* Handle problems with APM on Sony Vaio PCG-N505VX */
2127 swab_apm_power_in_minutes, "Sony VAIO",
2128 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2129 DMI_MATCH(DMI_BIOS_VERSION, "W2K06H0"),
2130 DMI_MATCH(DMI_BIOS_DATE, "02/03/00"), },
2131 },
2132 { /* Handle problems with APM on Sony Vaio PCG-XG29 */
2133 swab_apm_power_in_minutes, "Sony VAIO",
2134 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2135 DMI_MATCH(DMI_BIOS_VERSION, "R0117A0"),
2136 DMI_MATCH(DMI_BIOS_DATE, "04/25/00"), },
2137 },
2138 { /* Handle problems with APM on Sony Vaio PCG-Z600NE */
2139 swab_apm_power_in_minutes, "Sony VAIO",
2140 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2141 DMI_MATCH(DMI_BIOS_VERSION, "R0121Z1"),
2142 DMI_MATCH(DMI_BIOS_DATE, "05/11/00"), },
2143 },
2144 { /* Handle problems with APM on Sony Vaio PCG-Z600NE */
2145 swab_apm_power_in_minutes, "Sony VAIO",
2146 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2147 DMI_MATCH(DMI_BIOS_VERSION, "WME01Z1"),
2148 DMI_MATCH(DMI_BIOS_DATE, "08/11/00"), },
2149 },
2150 { /* Handle problems with APM on Sony Vaio PCG-Z600LEK(DE) */
2151 swab_apm_power_in_minutes, "Sony VAIO",
2152 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2153 DMI_MATCH(DMI_BIOS_VERSION, "R0206Z3"),
2154 DMI_MATCH(DMI_BIOS_DATE, "12/25/00"), },
2155 },
2156 { /* Handle problems with APM on Sony Vaio PCG-Z505LS */
2157 swab_apm_power_in_minutes, "Sony VAIO",
2158 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2159 DMI_MATCH(DMI_BIOS_VERSION, "R0203D0"),
2160 DMI_MATCH(DMI_BIOS_DATE, "05/12/00"), },
2161 },
2162 { /* Handle problems with APM on Sony Vaio PCG-Z505LS */
2163 swab_apm_power_in_minutes, "Sony VAIO",
2164 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2165 DMI_MATCH(DMI_BIOS_VERSION, "R0203Z3"),
2166 DMI_MATCH(DMI_BIOS_DATE, "08/25/00"), },
2167 },
2168 { /* Handle problems with APM on Sony Vaio PCG-Z505LS (with updated BIOS) */
2169 swab_apm_power_in_minutes, "Sony VAIO",
2170 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2171 DMI_MATCH(DMI_BIOS_VERSION, "R0209Z3"),
2172 DMI_MATCH(DMI_BIOS_DATE, "05/12/01"), },
2173 },
2174 { /* Handle problems with APM on Sony Vaio PCG-F104K */
2175 swab_apm_power_in_minutes, "Sony VAIO",
2176 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2177 DMI_MATCH(DMI_BIOS_VERSION, "R0204K2"),
2178 DMI_MATCH(DMI_BIOS_DATE, "08/28/00"), },
2179 },
2180
2181 { /* Handle problems with APM on Sony Vaio PCG-C1VN/C1VE */
2182 swab_apm_power_in_minutes, "Sony VAIO",
2183 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2184 DMI_MATCH(DMI_BIOS_VERSION, "R0208P1"),
2185 DMI_MATCH(DMI_BIOS_DATE, "11/09/00"), },
2186 },
2187 { /* Handle problems with APM on Sony Vaio PCG-C1VE */
2188 swab_apm_power_in_minutes, "Sony VAIO",
2189 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2190 DMI_MATCH(DMI_BIOS_VERSION, "R0204P1"),
2191 DMI_MATCH(DMI_BIOS_DATE, "09/12/00"), },
2192 },
2193 { /* Handle problems with APM on Sony Vaio PCG-C1VE */
2194 swab_apm_power_in_minutes, "Sony VAIO",
2195 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2196 DMI_MATCH(DMI_BIOS_VERSION, "WXPO1Z3"),
2197 DMI_MATCH(DMI_BIOS_DATE, "10/26/01"), },
2198 },
2199 { /* broken PM poweroff bios */
2200 set_realmode_power_off, "Award Software v4.60 PGMA",
2201 { DMI_MATCH(DMI_BIOS_VENDOR, "Award Software International, Inc."),
2202 DMI_MATCH(DMI_BIOS_VERSION, "4.60 PGMA"),
2203 DMI_MATCH(DMI_BIOS_DATE, "134526184"), },
2204 },
2205
2206 /* Generic per vendor APM settings */
2207
2208 { /* Allow interrupts during suspend on IBM laptops */
2209 set_apm_ints, "IBM",
2210 { DMI_MATCH(DMI_SYS_VENDOR, "IBM"), },
2211 },
2212
2213 { }
2214};
2215
2216/*
2217 * Just start the APM thread. We do NOT want to do APM BIOS
2218 * calls from anything but the APM thread, if for no other reason
2219 * than the fact that we don't trust the APM BIOS. This way,
2220 * most common APM BIOS problems that lead to protection errors
2221 * etc will have at least some level of being contained...
2222 *
2223 * In short, if something bad happens, at least we have a choice
2224 * of just killing the apm thread..
2225 */
2226static int __init apm_init(void)
2227{
2228 struct proc_dir_entry *apm_proc;
92f17f01 2229 struct desc_struct *gdt;
1da177e4 2230 int ret;
1da177e4
LT		 2231
2232 dmi_check_system(apm_dmi_table);
2233
2234 if (apm_info.bios.version == 0) {
2235 printk(KERN_INFO "apm: BIOS not found.\n");
2236 return -ENODEV;
2237 }
2238 printk(KERN_INFO
2239 "apm: BIOS version %d.%d Flags 0x%02x (Driver version %s)\n",
2240 ((apm_info.bios.version >> 8) & 0xff),
2241 (apm_info.bios.version & 0xff),
2242 apm_info.bios.flags,
2243 driver_version);
2244 if ((apm_info.bios.flags & APM_32_BIT_SUPPORT) == 0) {
2245 printk(KERN_INFO "apm: no 32 bit BIOS support\n");
2246 return -ENODEV;
2247 }
2248
2249 if (allow_ints)
2250 apm_info.allow_ints = 1;
2251 if (broken_psr)
2252 apm_info.get_power_status_broken = 1;
2253 if (realmode_power_off)
2254 apm_info.realmode_power_off = 1;
2255 /* User can override, but default is to trust DMI */
2256 if (apm_disabled != -1)
2257 apm_info.disabled = apm_disabled;
2258
2259 /*
2260 * Fix for the Compaq Contura 3/25c which reports BIOS version 0.1
2261 * but is reportedly a 1.0 BIOS.
2262 */
2263 if (apm_info.bios.version == 0x001)
2264 apm_info.bios.version = 0x100;
2265
2266 /* BIOS < 1.2 doesn't set cseg_16_len */
2267 if (apm_info.bios.version < 0x102)
2268 apm_info.bios.cseg_16_len = 0; /* 64k */
2269
2270 if (debug) {
2271 printk(KERN_INFO "apm: entry %x:%lx cseg16 %x dseg %x",
2272 apm_info.bios.cseg, apm_info.bios.offset,
2273 apm_info.bios.cseg_16, apm_info.bios.dseg);
2274 if (apm_info.bios.version > 0x100)
2275 printk(" cseg len %x, dseg len %x",
2276 apm_info.bios.cseg_len,
2277 apm_info.bios.dseg_len);
2278 if (apm_info.bios.version > 0x101)
2279 printk(" cseg16 len %x", apm_info.bios.cseg_16_len);
2280 printk("\n");
2281 }
2282
2283 if (apm_info.disabled) {
2284 printk(KERN_NOTICE "apm: disabled on user request.\n");
2285 return -ENODEV;
2286 }
2287 if ((num_online_cpus() > 1) && !power_off && !smp) {
2288 printk(KERN_NOTICE "apm: disabled - APM is not SMP safe.\n");
2289 apm_info.disabled = 1;
2290 return -ENODEV;
2291 }
2292 if (PM_IS_ACTIVE()) {
2293 printk(KERN_NOTICE "apm: overridden by ACPI.\n");
2294 apm_info.disabled = 1;
2295 return -ENODEV;
2296 }
987d4613 2297#ifdef CONFIG_PM_LEGACY
1da177e4 2298 pm_active = 1;
987d4613 2299#endif
1da177e4
LT		 2300
2301 /*
2302 * Set up a segment that references the real mode segment 0x40
2303 * that extends up to the end of page zero (that we have reserved).
2304 * This is for buggy BIOS's that refer to (real mode) segment 0x40
2305 * even though they are called in protected mode.
2306 */
2307 set_base(bad_bios_desc, __va((unsigned long)0x40 << 4));
2308 _set_limit((char *)&bad_bios_desc, 4095 - (0x40 << 4));
2309
3012d2d2
ZA		 2310 /*
2311 * Set up the long jump entry point to the APM BIOS, which is called
2312 * from inline assembly.
2313 */
1da177e4
LT		 2314 apm_bios_entry.offset = apm_info.bios.offset;
2315 apm_bios_entry.segment = APM_CS;
2316
3012d2d2
ZA		 2317 /*
2318 * The APM 1.1 BIOS is supposed to provide limit information that it
2319 * recognizes. Many machines do this correctly, but many others do
2320 * not restrict themselves to their claimed limit. When this happens,
2321 * they will cause a segmentation violation in the kernel at boot time.
2322 * Most BIOS's, however, will respect a 64k limit, so we use that.
92f17f01
ZA		 2323 *
2324 * Note we only set APM segments on CPU zero, since we pin the APM
2325 * code to that CPU.
3012d2d2 2326 */
92f17f01
ZA		 2327 gdt = get_cpu_gdt_table(0);
2328 set_base(gdt[APM_CS >> 3],
2329 __va((unsigned long)apm_info.bios.cseg << 4));
2330 set_base(gdt[APM_CS_16 >> 3],
2331 __va((unsigned long)apm_info.bios.cseg_16 << 4));
2332 set_base(gdt[APM_DS >> 3],
2333 __va((unsigned long)apm_info.bios.dseg << 4));
1da177e4
LT		 2334
2335 apm_proc = create_proc_info_entry("apm", 0, NULL, apm_get_info);
2336 if (apm_proc)
2337 apm_proc->owner = THIS_MODULE;
2338
2339 ret = kernel_thread(apm, NULL, CLONE_KERNEL | SIGCHLD);
2340 if (ret < 0) {
2341 printk(KERN_ERR "apm: disabled - Unable to start kernel thread.\n");
c94a62aa 2342 remove_proc_entry("apm", NULL);
1da177e4
LT		 2343 return -ENOMEM;
2344 }
2345
2346 if (num_online_cpus() > 1 && !smp ) {
2347 printk(KERN_NOTICE
2348 "apm: disabled - APM is not SMP safe (power off active).\n");
2349 return 0;
2350 }
2351
c94a62aa
NH		 2352 /*
2353 * Note we don't actually care if the misc_device cannot be registered.
2354 * this driver can do its job without it, even if userspace can't
2355 * control it. just log the error
2356 */
2357 if (misc_register(&apm_device))
2358 printk(KERN_WARNING "apm: Could not register misc device.\n");
1da177e4
LT		 2359
2360 if (HZ != 100)
2361 idle_period = (idle_period * HZ) / 100;
2362 if (idle_threshold < 100) {
2363 original_pm_idle = pm_idle;
2364 pm_idle = apm_cpu_idle;
2365 set_pm_idle = 1;
2366 }
2367
2368 return 0;
2369}
2370
2371static void __exit apm_exit(void)
2372{
2373 int error;
2374
2375 if (set_pm_idle) {
2376 pm_idle = original_pm_idle;
2377 /*
2378 * We are about to unload the current idle thread pm callback
2379 * (pm_idle), Wait for all processors to update cached/local
2380 * copies of pm_idle before proceeding.
2381 */
2382 cpu_idle_wait();
2383 }
2384 if (((apm_info.bios.flags & APM_BIOS_DISENGAGED) == 0)
2385 && (apm_info.connection_version > 0x0100)) {
2386 error = apm_engage_power_management(APM_DEVICE_ALL, 0);
2387 if (error)
2388 apm_error("disengage power management", error);
2389 }
2390 misc_deregister(&apm_device);
2391 remove_proc_entry("apm", NULL);
2392 if (power_off)
2393 pm_power_off = NULL;
2394 exit_kapmd = 1;
2395 while (kapmd_running)
2396 schedule();
987d4613 2397#ifdef CONFIG_PM_LEGACY
1da177e4 2398 pm_active = 0;
987d4613 2399#endif
1da177e4
LT		 2400}
2401
2402module_init(apm_init);
2403module_exit(apm_exit);
2404
2405MODULE_AUTHOR("Stephen Rothwell");
2406MODULE_DESCRIPTION("Advanced Power Management");
2407MODULE_LICENSE("GPL");
2408module_param(debug, bool, 0644);
2409MODULE_PARM_DESC(debug, "Enable debug mode");
2410module_param(power_off, bool, 0444);
2411MODULE_PARM_DESC(power_off, "Enable power off");
2412module_param(bounce_interval, int, 0444);
2413MODULE_PARM_DESC(bounce_interval,
2414 "Set the number of ticks to ignore suspend bounces");
2415module_param(allow_ints, bool, 0444);
2416MODULE_PARM_DESC(allow_ints, "Allow interrupts during BIOS calls");
2417module_param(broken_psr, bool, 0444);
2418MODULE_PARM_DESC(broken_psr, "BIOS has a broken GetPowerStatus call");
2419module_param(realmode_power_off, bool, 0444);
2420MODULE_PARM_DESC(realmode_power_off,
2421 "Switch to real mode before powering off");
2422module_param(idle_threshold, int, 0444);
2423MODULE_PARM_DESC(idle_threshold,
2424 "System idle percentage above which to make APM BIOS idle calls");
2425module_param(idle_period, int, 0444);
2426MODULE_PARM_DESC(idle_period,
2427 "Period (in sec/100) over which to caculate the idle percentage");
2428module_param(smp, bool, 0444);
2429MODULE_PARM_DESC(smp,
2430 "Set this to enable APM use on an SMP platform. Use with caution on older systems");
2431MODULE_ALIAS_MISCDEV(APM_MINOR_DEV);
Linux 6.x block layer and io_uring tree(s)