Linux Audio

Check our new training course

Loading...
v3.1
   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 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 compiler/assembler differences.
  70 *         Only try to turn off the first display device.
  71 *         Fix OOPS at power off with no APM BIOS by Jan Echternach
  72 *                   <echter@informatik.uni-rostock.de>
  73 *         Stephen Rothwell
  74 *    1.7: Modify driver's cached copy of the disabled/disengaged flags
  75 *         to reflect current state of APM BIOS.
  76 *         Chris Rankin <rankinc@bellsouth.net>
  77 *         Reset interrupt 0 timer to 100Hz after suspend
  78 *         Chad Miller <cmiller@surfsouth.com>
  79 *         Add CONFIG_APM_IGNORE_SUSPEND_BOUNCE
  80 *         Richard Gooch <rgooch@atnf.csiro.au>
  81 *         Allow boot time disabling of APM
  82 *         Make boot messages far less verbose by default
  83 *         Make asm safer
  84 *         Stephen Rothwell
  85 *    1.8: Add CONFIG_APM_RTC_IS_GMT
  86 *         Richard Gooch <rgooch@atnf.csiro.au>
  87 *         change APM_NOINTS to CONFIG_APM_ALLOW_INTS
  88 *         remove dependency on CONFIG_PROC_FS
  89 *         Stephen Rothwell
  90 *    1.9: Fix small typo.  <laslo@wodip.opole.pl>
  91 *         Try to cope with BIOS's that need to have all display
  92 *         devices blanked and not just the first one.
  93 *         Ross Paterson <ross@soi.city.ac.uk>
  94 *         Fix segment limit setting it has always been wrong as
  95 *         the segments needed to have byte granularity.
  96 *         Mark a few things __init.
  97 *         Add hack to allow power off of SMP systems by popular request.
  98 *         Use CONFIG_SMP instead of __SMP__
  99 *         Ignore BOUNCES for three seconds.
 100 *         Stephen Rothwell
 101 *   1.10: Fix for Thinkpad return code.
 102 *         Merge 2.2 and 2.3 drivers.
 103 *         Remove APM dependencies in arch/i386/kernel/process.c
 104 *         Remove APM dependencies in drivers/char/sysrq.c
 105 *         Reset time across standby.
 106 *         Allow more inititialisation on SMP.
 107 *         Remove CONFIG_APM_POWER_OFF and make it boot time
 108 *         configurable (default on).
 109 *         Make debug only a boot time parameter (remove APM_DEBUG).
 110 *         Try to blank all devices on any error.
 111 *   1.11: Remove APM dependencies in drivers/char/console.c
 112 *         Check nr_running to detect if we are idle (from
 113 *         Borislav Deianov <borislav@lix.polytechnique.fr>)
 114 *         Fix for bioses that don't zero the top part of the
 115 *         entrypoint offset (Mario Sitta <sitta@al.unipmn.it>)
 116 *         (reported by Panos Katsaloulis <teras@writeme.com>).
 117 *         Real mode power off patch (Walter Hofmann
 118 *         <Walter.Hofmann@physik.stud.uni-erlangen.de>).
 119 *   1.12: Remove CONFIG_SMP as the compiler will optimize
 120 *         the code away anyway (smp_num_cpus == 1 in UP)
 121 *         noted by Artur Skawina <skawina@geocities.com>.
 122 *         Make power off under SMP work again.
 123 *         Fix thinko with initial engaging of BIOS.
 124 *         Make sure power off only happens on CPU 0
 125 *         (Paul "Rusty" Russell <rusty@rustcorp.com.au>).
 126 *         Do error notification to user mode if BIOS calls fail.
 127 *         Move entrypoint offset fix to ...boot/setup.S
 128 *         where it belongs (Cosmos <gis88564@cis.nctu.edu.tw>).
 129 *         Remove smp-power-off. SMP users must now specify
 130 *         "apm=power-off" on the kernel command line. Suggested
 131 *         by Jim Avera <jima@hal.com>, modified by Alan Cox
 132 *         <alan@lxorguk.ukuu.org.uk>.
 133 *         Register the /proc/apm entry even on SMP so that
 134 *         scripts that check for it before doing power off
 135 *         work (Jim Avera <jima@hal.com>).
 136 *   1.13: Changes for new pm_ interfaces (Andy Henroid
 137 *         <andy_henroid@yahoo.com>).
 138 *         Modularize the code.
 139 *         Fix the Thinkpad (again) :-( (CONFIG_APM_IGNORE_MULTIPLE_SUSPENDS
 140 *         is now the way life works).
 141 *         Fix thinko in suspend() (wrong return).
 142 *         Notify drivers on critical suspend.
 143 *         Make kapmd absorb more idle time (Pavel Machek <pavel@ucw.cz>
 144 *         modified by sfr).
 145 *         Disable interrupts while we are suspended (Andy Henroid
 146 *         <andy_henroid@yahoo.com> fixed by sfr).
 147 *         Make power off work on SMP again (Tony Hoyle
 148 *         <tmh@magenta-logic.com> and <zlatko@iskon.hr>) modified by sfr.
 149 *         Remove CONFIG_APM_SUSPEND_BOUNCE.  The bounce ignore
 150 *         interval is now configurable.
 151 *   1.14: Make connection version persist across module unload/load.
 152 *         Enable and engage power management earlier.
 153 *         Disengage power management on module unload.
 154 *         Changed to use the sysrq-register hack for registering the
 155 *         power off function called by magic sysrq based upon discussions
 156 *         in irc://irc.openprojects.net/#kernelnewbies
 157 *         (Crutcher Dunnavant <crutcher+kernel@datastacks.com>).
 158 *         Make CONFIG_APM_REAL_MODE_POWER_OFF run time configurable.
 159 *         (Arjan van de Ven <arjanv@redhat.com>) modified by sfr.
 160 *         Work around byte swap bug in one of the Vaio's BIOS's
 161 *         (Marc Boucher <marc@mbsi.ca>).
 162 *         Exposed the disable flag to dmi so that we can handle known
 163 *         broken APM (Alan Cox <alan@lxorguk.ukuu.org.uk>).
 164 *   1.14ac: If the BIOS says "I slowed the CPU down" then don't spin
 165 *         calling it - instead idle. (Alan Cox <alan@lxorguk.ukuu.org.uk>)
 166 *         If an APM idle fails log it and idle sensibly
 167 *   1.15: Don't queue events to clients who open the device O_WRONLY.
 168 *         Don't expect replies from clients who open the device O_RDONLY.
 169 *         (Idea from Thomas Hood)
 170 *         Minor waitqueue cleanups. (John Fremlin <chief@bandits.org>)
 171 *   1.16: Fix idle calling. (Andreas Steinmetz <ast@domdv.de> et al.)
 172 *         Notify listeners of standby or suspend events before notifying
 173 *         drivers. Return EBUSY to ioctl() if suspend is rejected.
 174 *         (Russell King <rmk@arm.linux.org.uk> and Thomas Hood)
 175 *         Ignore first resume after we generate our own resume event
 176 *         after a suspend (Thomas Hood)
 177 *         Daemonize now gets rid of our controlling terminal (sfr).
 178 *         CONFIG_APM_CPU_IDLE now just affects the default value of
 179 *         idle_threshold (sfr).
 180 *         Change name of kernel apm daemon (as it no longer idles) (sfr).
 181 *   1.16ac: Fix up SMP support somewhat. You can now force SMP on and we
 182 *	   make _all_ APM calls on the CPU#0. Fix unsafe sign bug.
 183 *	   TODO: determine if its "boot CPU" or "CPU0" we want to lock to.
 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 from
 193 * http://www.microsoft.com/whdc/archive/amp_12.mspx  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/whdc/archive/amp_12.mspx]
 202 */
 203
 
 
 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/seq_file.h>
 215#include <linux/miscdevice.h>
 216#include <linux/apm_bios.h>
 217#include <linux/init.h>
 218#include <linux/time.h>
 219#include <linux/sched.h>
 220#include <linux/pm.h>
 221#include <linux/capability.h>
 222#include <linux/device.h>
 223#include <linux/kernel.h>
 224#include <linux/freezer.h>
 225#include <linux/smp.h>
 226#include <linux/dmi.h>
 227#include <linux/suspend.h>
 228#include <linux/kthread.h>
 229#include <linux/jiffies.h>
 230#include <linux/acpi.h>
 231#include <linux/syscore_ops.h>
 232#include <linux/i8253.h>
 
 233
 234#include <asm/system.h>
 235#include <asm/uaccess.h>
 236#include <asm/desc.h>
 237#include <asm/olpc.h>
 238#include <asm/paravirt.h>
 239#include <asm/reboot.h>
 240
 241#if defined(CONFIG_APM_DISPLAY_BLANK) && defined(CONFIG_VT)
 242extern int (*console_blank_hook)(int);
 243#endif
 244
 245/*
 246 * The apm_bios device is one of the misc char devices.
 247 * This is its minor number.
 248 */
 249#define	APM_MINOR_DEV	134
 250
 251/*
 252 * See Documentation/Config.help for the configuration options.
 253 *
 254 * Various options can be changed at boot time as follows:
 255 * (We allow underscores for compatibility with the modules code)
 256 *	apm=on/off			enable/disable APM
 257 *	    [no-]allow[-_]ints		allow interrupts during BIOS calls
 258 *	    [no-]broken[-_]psr		BIOS has a broken GetPowerStatus call
 259 *	    [no-]realmode[-_]power[-_]off	switch to real mode before
 260 *	    					powering off
 261 *	    [no-]debug			log some debugging messages
 262 *	    [no-]power[-_]off		power off on shutdown
 263 *	    [no-]smp			Use apm even on an SMP box
 264 *	    bounce[-_]interval=<n>	number of ticks to ignore suspend
 265 *	    				bounces
 266 *          idle[-_]threshold=<n>       System idle percentage above which to
 267 *                                      make APM BIOS idle calls. Set it to
 268 *                                      100 to disable.
 269 *          idle[-_]period=<n>          Period (in 1/100s of a second) over
 270 *                                      which the idle percentage is
 271 *                                      calculated.
 272 */
 273
 274/* KNOWN PROBLEM MACHINES:
 275 *
 276 * U: TI 4000M TravelMate: BIOS is *NOT* APM compliant
 277 *                         [Confirmed by TI representative]
 278 * ?: ACER 486DX4/75: uses dseg 0040, in violation of APM specification
 279 *                    [Confirmed by BIOS disassembly]
 280 *                    [This may work now ...]
 281 * P: Toshiba 1950S: battery life information only gets updated after resume
 282 * P: Midwest Micro Soundbook Elite DX2/66 monochrome: screen blanking
 283 * 	broken in BIOS [Reported by Garst R. Reese <reese@isn.net>]
 284 * ?: AcerNote-950: oops on reading /proc/apm - workaround is a WIP
 285 * 	Neale Banks <neale@lowendale.com.au> December 2000
 286 *
 287 * Legend: U = unusable with APM patches
 288 *         P = partially usable with APM patches
 289 */
 290
 291/*
 292 * Define as 1 to make the driver always call the APM BIOS busy
 293 * routine even if the clock was not reported as slowed by the
 294 * idle routine.  Otherwise, define as 0.
 295 */
 296#define ALWAYS_CALL_BUSY   1
 297
 298/*
 299 * Define to make the APM BIOS calls zero all data segment registers (so
 300 * that an incorrect BIOS implementation will cause a kernel panic if it
 301 * tries to write to arbitrary memory).
 302 */
 303#define APM_ZERO_SEGS
 304
 305#include <asm/apm.h>
 306
 307/*
 308 * Define to re-initialize the interrupt 0 timer to 100 Hz after a suspend.
 309 * This patched by Chad Miller <cmiller@surfsouth.com>, original code by
 310 * David Chen <chen@ctpa04.mit.edu>
 311 */
 312#undef INIT_TIMER_AFTER_SUSPEND
 313
 314#ifdef INIT_TIMER_AFTER_SUSPEND
 315#include <linux/timex.h>
 316#include <asm/io.h>
 317#include <linux/delay.h>
 318#endif
 319
 320/*
 321 * Need to poll the APM BIOS every second
 322 */
 323#define APM_CHECK_TIMEOUT	(HZ)
 324
 325/*
 326 * Ignore suspend events for this amount of time after a resume
 327 */
 328#define DEFAULT_BOUNCE_INTERVAL	(3 * HZ)
 329
 330/*
 331 * Maximum number of events stored
 332 */
 333#define APM_MAX_EVENTS		20
 334
 335/*
 336 * The per-file APM data
 337 */
 338struct apm_user {
 339	int		magic;
 340	struct apm_user *next;
 341	unsigned int	suser: 1;
 342	unsigned int	writer: 1;
 343	unsigned int	reader: 1;
 344	unsigned int	suspend_wait: 1;
 345	int		suspend_result;
 346	int		suspends_pending;
 347	int		standbys_pending;
 348	int		suspends_read;
 349	int		standbys_read;
 350	int		event_head;
 351	int		event_tail;
 352	apm_event_t	events[APM_MAX_EVENTS];
 353};
 354
 355/*
 356 * The magic number in apm_user
 357 */
 358#define APM_BIOS_MAGIC		0x4101
 359
 360/*
 361 * idle percentage above which bios idle calls are done
 362 */
 363#ifdef CONFIG_APM_CPU_IDLE
 364#warning deprecated CONFIG_APM_CPU_IDLE will be deleted in 2012
 365#define DEFAULT_IDLE_THRESHOLD	95
 366#else
 367#define DEFAULT_IDLE_THRESHOLD	100
 368#endif
 369#define DEFAULT_IDLE_PERIOD	(100 / 3)
 370
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 371/*
 372 * Local variables
 373 */
 374static struct {
 375	unsigned long	offset;
 376	unsigned short	segment;
 377} apm_bios_entry;
 378static int clock_slowed;
 379static int idle_threshold __read_mostly = DEFAULT_IDLE_THRESHOLD;
 380static int idle_period __read_mostly = DEFAULT_IDLE_PERIOD;
 381static int set_pm_idle;
 382static int suspends_pending;
 383static int standbys_pending;
 384static int ignore_sys_suspend;
 385static int ignore_normal_resume;
 386static int bounce_interval __read_mostly = DEFAULT_BOUNCE_INTERVAL;
 387
 388static int debug __read_mostly;
 389static int smp __read_mostly;
 390static int apm_disabled = -1;
 391#ifdef CONFIG_SMP
 392static int power_off;
 393#else
 394static int power_off = 1;
 395#endif
 396static int realmode_power_off;
 397#ifdef CONFIG_APM_ALLOW_INTS
 398static int allow_ints = 1;
 399#else
 400static int allow_ints;
 401#endif
 402static int broken_psr;
 403
 404static DECLARE_WAIT_QUEUE_HEAD(apm_waitqueue);
 405static DECLARE_WAIT_QUEUE_HEAD(apm_suspend_waitqueue);
 406static struct apm_user *user_list;
 407static DEFINE_SPINLOCK(user_list_lock);
 408static DEFINE_MUTEX(apm_mutex);
 409
 410/*
 411 * Set up a segment that references the real mode segment 0x40
 412 * that extends up to the end of page zero (that we have reserved).
 413 * This is for buggy BIOS's that refer to (real mode) segment 0x40
 414 * even though they are called in protected mode.
 415 */
 416static struct desc_struct bad_bios_desc = GDT_ENTRY_INIT(0x4092,
 417			(unsigned long)__va(0x400UL), PAGE_SIZE - 0x400 - 1);
 418
 419static const char driver_version[] = "1.16ac";	/* no spaces */
 420
 421static struct task_struct *kapmd_task;
 422
 423/*
 424 *	APM event names taken from the APM 1.2 specification. These are
 425 *	the message codes that the BIOS uses to tell us about events
 426 */
 427static const char * const apm_event_name[] = {
 428	"system standby",
 429	"system suspend",
 430	"normal resume",
 431	"critical resume",
 432	"low battery",
 433	"power status change",
 434	"update time",
 435	"critical suspend",
 436	"user standby",
 437	"user suspend",
 438	"system standby resume",
 439	"capabilities change"
 440};
 441#define NR_APM_EVENT_NAME ARRAY_SIZE(apm_event_name)
 442
 443typedef struct lookup_t {
 444	int	key;
 445	char 	*msg;
 446} lookup_t;
 447
 448/*
 449 *	The BIOS returns a set of standard error codes in AX when the
 450 *	carry flag is set.
 451 */
 452
 453static const lookup_t error_table[] = {
 454/* N/A	{ APM_SUCCESS,		"Operation succeeded" }, */
 455	{ APM_DISABLED,		"Power management disabled" },
 456	{ APM_CONNECTED,	"Real mode interface already connected" },
 457	{ APM_NOT_CONNECTED,	"Interface not connected" },
 458	{ APM_16_CONNECTED,	"16 bit interface already connected" },
 459/* N/A	{ APM_16_UNSUPPORTED,	"16 bit interface not supported" }, */
 460	{ APM_32_CONNECTED,	"32 bit interface already connected" },
 461	{ APM_32_UNSUPPORTED,	"32 bit interface not supported" },
 462	{ APM_BAD_DEVICE,	"Unrecognized device ID" },
 463	{ APM_BAD_PARAM,	"Parameter out of range" },
 464	{ APM_NOT_ENGAGED,	"Interface not engaged" },
 465	{ APM_BAD_FUNCTION,     "Function not supported" },
 466	{ APM_RESUME_DISABLED,	"Resume timer disabled" },
 467	{ APM_BAD_STATE,	"Unable to enter requested state" },
 468/* N/A	{ APM_NO_EVENTS,	"No events pending" }, */
 469	{ APM_NO_ERROR,		"BIOS did not set a return code" },
 470	{ APM_NOT_PRESENT,	"No APM present" }
 471};
 472#define ERROR_COUNT	ARRAY_SIZE(error_table)
 473
 474/**
 475 *	apm_error	-	display an APM error
 476 *	@str: information string
 477 *	@err: APM BIOS return code
 478 *
 479 *	Write a meaningful log entry to the kernel log in the event of
 480 *	an APM error.  Note that this also handles (negative) kernel errors.
 481 */
 482
 483static void apm_error(char *str, int err)
 484{
 485	int i;
 486
 487	for (i = 0; i < ERROR_COUNT; i++)
 488		if (error_table[i].key == err)
 489			break;
 490	if (i < ERROR_COUNT)
 491		printk(KERN_NOTICE "apm: %s: %s\n", str, error_table[i].msg);
 492	else if (err < 0)
 493		printk(KERN_NOTICE "apm: %s: linux error code %i\n", str, err);
 494	else
 495		printk(KERN_NOTICE "apm: %s: unknown error code %#2.2x\n",
 496		       str, err);
 497}
 498
 499/*
 500 * These are the actual BIOS calls.  Depending on APM_ZERO_SEGS and
 501 * apm_info.allow_ints, we are being really paranoid here!  Not only
 502 * are interrupts disabled, but all the segment registers (except SS)
 503 * are saved and zeroed this means that if the BIOS tries to reference
 504 * any data without explicitly loading the segment registers, the kernel
 505 * will fault immediately rather than have some unforeseen circumstances
 506 * for the rest of the kernel.  And it will be very obvious!  :-) Doing
 507 * this depends on CS referring to the same physical memory as DS so that
 508 * DS can be zeroed before the call. Unfortunately, we can't do anything
 509 * about the stack segment/pointer.  Also, we tell the compiler that
 510 * everything could change.
 511 *
 512 * Also, we KNOW that for the non error case of apm_bios_call, there
 513 * is no useful data returned in the low order 8 bits of eax.
 514 */
 515
 516static inline unsigned long __apm_irq_save(void)
 517{
 518	unsigned long flags;
 519	local_save_flags(flags);
 520	if (apm_info.allow_ints) {
 521		if (irqs_disabled_flags(flags))
 522			local_irq_enable();
 523	} else
 524		local_irq_disable();
 525
 526	return flags;
 527}
 528
 529#define apm_irq_save(flags) \
 530	do { flags = __apm_irq_save(); } while (0)
 531
 532static inline void apm_irq_restore(unsigned long flags)
 533{
 534	if (irqs_disabled_flags(flags))
 535		local_irq_disable();
 536	else if (irqs_disabled())
 537		local_irq_enable();
 538}
 539
 540#ifdef APM_ZERO_SEGS
 541#	define APM_DECL_SEGS \
 542		unsigned int saved_fs; unsigned int saved_gs;
 543#	define APM_DO_SAVE_SEGS \
 544		savesegment(fs, saved_fs); savesegment(gs, saved_gs)
 545#	define APM_DO_RESTORE_SEGS \
 546		loadsegment(fs, saved_fs); loadsegment(gs, saved_gs)
 547#else
 548#	define APM_DECL_SEGS
 549#	define APM_DO_SAVE_SEGS
 550#	define APM_DO_RESTORE_SEGS
 551#endif
 552
 553struct apm_bios_call {
 554	u32 func;
 555	/* In and out */
 556	u32 ebx;
 557	u32 ecx;
 558	/* Out only */
 559	u32 eax;
 560	u32 edx;
 561	u32 esi;
 562
 563	/* Error: -ENOMEM, or bits 8-15 of eax */
 564	int err;
 565};
 566
 567/**
 568 *	__apm_bios_call - Make an APM BIOS 32bit call
 569 *	@_call: pointer to struct apm_bios_call.
 570 *
 571 *	Make an APM call using the 32bit protected mode interface. The
 572 *	caller is responsible for knowing if APM BIOS is configured and
 573 *	enabled. This call can disable interrupts for a long period of
 574 *	time on some laptops.  The return value is in AH and the carry
 575 *	flag is loaded into AL.  If there is an error, then the error
 576 *	code is returned in AH (bits 8-15 of eax) and this function
 577 *	returns non-zero.
 578 *
 579 *	Note: this makes the call on the current CPU.
 580 */
 581static long __apm_bios_call(void *_call)
 582{
 583	APM_DECL_SEGS
 584	unsigned long		flags;
 585	int			cpu;
 586	struct desc_struct	save_desc_40;
 587	struct desc_struct	*gdt;
 588	struct apm_bios_call	*call = _call;
 589
 590	cpu = get_cpu();
 591	BUG_ON(cpu != 0);
 592	gdt = get_cpu_gdt_table(cpu);
 593	save_desc_40 = gdt[0x40 / 8];
 594	gdt[0x40 / 8] = bad_bios_desc;
 595
 596	apm_irq_save(flags);
 597	APM_DO_SAVE_SEGS;
 598	apm_bios_call_asm(call->func, call->ebx, call->ecx,
 599			  &call->eax, &call->ebx, &call->ecx, &call->edx,
 600			  &call->esi);
 601	APM_DO_RESTORE_SEGS;
 602	apm_irq_restore(flags);
 603	gdt[0x40 / 8] = save_desc_40;
 604	put_cpu();
 605
 606	return call->eax & 0xff;
 607}
 608
 609/* Run __apm_bios_call or __apm_bios_call_simple on CPU 0 */
 610static int on_cpu0(long (*fn)(void *), struct apm_bios_call *call)
 611{
 612	int ret;
 613
 614	/* Don't bother with work_on_cpu in the common case, so we don't
 615	 * have to worry about OOM or overhead. */
 616	if (get_cpu() == 0) {
 617		ret = fn(call);
 618		put_cpu();
 619	} else {
 620		put_cpu();
 621		ret = work_on_cpu(0, fn, call);
 622	}
 623
 624	/* work_on_cpu can fail with -ENOMEM */
 625	if (ret < 0)
 626		call->err = ret;
 627	else
 628		call->err = (call->eax >> 8) & 0xff;
 629
 630	return ret;
 631}
 632
 633/**
 634 *	apm_bios_call	-	Make an APM BIOS 32bit call (on CPU 0)
 635 *	@call: the apm_bios_call registers.
 636 *
 637 *	If there is an error, it is returned in @call.err.
 638 */
 639static int apm_bios_call(struct apm_bios_call *call)
 640{
 641	return on_cpu0(__apm_bios_call, call);
 642}
 643
 644/**
 645 *	__apm_bios_call_simple - Make an APM BIOS 32bit call (on CPU 0)
 646 *	@_call: pointer to struct apm_bios_call.
 647 *
 648 *	Make a BIOS call that returns one value only, or just status.
 649 *	If there is an error, then the error code is returned in AH
 650 *	(bits 8-15 of eax) and this function returns non-zero (it can
 651 *	also return -ENOMEM). This is used for simpler BIOS operations.
 652 *	This call may hold interrupts off for a long time on some laptops.
 653 *
 654 *	Note: this makes the call on the current CPU.
 655 */
 656static long __apm_bios_call_simple(void *_call)
 657{
 658	u8			error;
 659	APM_DECL_SEGS
 660	unsigned long		flags;
 661	int			cpu;
 662	struct desc_struct	save_desc_40;
 663	struct desc_struct	*gdt;
 664	struct apm_bios_call	*call = _call;
 665
 666	cpu = get_cpu();
 667	BUG_ON(cpu != 0);
 668	gdt = get_cpu_gdt_table(cpu);
 669	save_desc_40 = gdt[0x40 / 8];
 670	gdt[0x40 / 8] = bad_bios_desc;
 671
 672	apm_irq_save(flags);
 673	APM_DO_SAVE_SEGS;
 674	error = apm_bios_call_simple_asm(call->func, call->ebx, call->ecx,
 675					 &call->eax);
 676	APM_DO_RESTORE_SEGS;
 677	apm_irq_restore(flags);
 678	gdt[0x40 / 8] = save_desc_40;
 679	put_cpu();
 680	return error;
 681}
 682
 683/**
 684 *	apm_bios_call_simple	-	make a simple APM BIOS 32bit call
 685 *	@func: APM function to invoke
 686 *	@ebx_in: EBX register value for BIOS call
 687 *	@ecx_in: ECX register value for BIOS call
 688 *	@eax: EAX register on return from the BIOS call
 689 *	@err: bits
 690 *
 691 *	Make a BIOS call that returns one value only, or just status.
 692 *	If there is an error, then the error code is returned in @err
 693 *	and this function returns non-zero. This is used for simpler
 694 *	BIOS operations.  This call may hold interrupts off for a long
 695 *	time on some laptops.
 696 */
 697static int apm_bios_call_simple(u32 func, u32 ebx_in, u32 ecx_in, u32 *eax,
 698				int *err)
 699{
 700	struct apm_bios_call call;
 701	int ret;
 702
 703	call.func = func;
 704	call.ebx = ebx_in;
 705	call.ecx = ecx_in;
 706
 707	ret = on_cpu0(__apm_bios_call_simple, &call);
 708	*eax = call.eax;
 709	*err = call.err;
 710	return ret;
 711}
 712
 713/**
 714 *	apm_driver_version	-	APM driver version
 715 *	@val:	loaded with the APM version on return
 716 *
 717 *	Retrieve the APM version supported by the BIOS. This is only
 718 *	supported for APM 1.1 or higher. An error indicates APM 1.0 is
 719 *	probably present.
 720 *
 721 *	On entry val should point to a value indicating the APM driver
 722 *	version with the high byte being the major and the low byte the
 723 *	minor number both in BCD
 724 *
 725 *	On return it will hold the BIOS revision supported in the
 726 *	same format.
 727 */
 728
 729static int apm_driver_version(u_short *val)
 730{
 731	u32 eax;
 732	int err;
 733
 734	if (apm_bios_call_simple(APM_FUNC_VERSION, 0, *val, &eax, &err))
 735		return err;
 736	*val = eax;
 737	return APM_SUCCESS;
 738}
 739
 740/**
 741 *	apm_get_event	-	get an APM event from the BIOS
 742 *	@event: pointer to the event
 743 *	@info: point to the event information
 744 *
 745 *	The APM BIOS provides a polled information for event
 746 *	reporting. The BIOS expects to be polled at least every second
 747 *	when events are pending. When a message is found the caller should
 748 *	poll until no more messages are present.  However, this causes
 749 *	problems on some laptops where a suspend event notification is
 750 *	not cleared until it is acknowledged.
 751 *
 752 *	Additional information is returned in the info pointer, providing
 753 *	that APM 1.2 is in use. If no messges are pending the value 0x80
 754 *	is returned (No power management events pending).
 755 */
 756static int apm_get_event(apm_event_t *event, apm_eventinfo_t *info)
 757{
 758	struct apm_bios_call call;
 759
 760	call.func = APM_FUNC_GET_EVENT;
 761	call.ebx = call.ecx = 0;
 762
 763	if (apm_bios_call(&call))
 764		return call.err;
 765
 766	*event = call.ebx;
 767	if (apm_info.connection_version < 0x0102)
 768		*info = ~0; /* indicate info not valid */
 769	else
 770		*info = call.ecx;
 771	return APM_SUCCESS;
 772}
 773
 774/**
 775 *	set_power_state	-	set the power management state
 776 *	@what: which items to transition
 777 *	@state: state to transition to
 778 *
 779 *	Request an APM change of state for one or more system devices. The
 780 *	processor state must be transitioned last of all. what holds the
 781 *	class of device in the upper byte and the device number (0xFF for
 782 *	all) for the object to be transitioned.
 783 *
 784 *	The state holds the state to transition to, which may in fact
 785 *	be an acceptance of a BIOS requested state change.
 786 */
 787
 788static int set_power_state(u_short what, u_short state)
 789{
 790	u32 eax;
 791	int err;
 792
 793	if (apm_bios_call_simple(APM_FUNC_SET_STATE, what, state, &eax, &err))
 794		return err;
 795	return APM_SUCCESS;
 796}
 797
 798/**
 799 *	set_system_power_state - set system wide power state
 800 *	@state: which state to enter
 801 *
 802 *	Transition the entire system into a new APM power state.
 803 */
 804
 805static int set_system_power_state(u_short state)
 806{
 807	return set_power_state(APM_DEVICE_ALL, state);
 808}
 809
 810/**
 811 *	apm_do_idle	-	perform power saving
 812 *
 813 *	This function notifies the BIOS that the processor is (in the view
 814 *	of the OS) idle. It returns -1 in the event that the BIOS refuses
 815 *	to handle the idle request. On a success the function returns 1
 816 *	if the BIOS did clock slowing or 0 otherwise.
 817 */
 818
 819static int apm_do_idle(void)
 820{
 821	u32 eax;
 822	u8 ret = 0;
 823	int idled = 0;
 824	int polling;
 825	int err = 0;
 826
 827	polling = !!(current_thread_info()->status & TS_POLLING);
 828	if (polling) {
 829		current_thread_info()->status &= ~TS_POLLING;
 830		/*
 831		 * TS_POLLING-cleared state must be visible before we
 832		 * test NEED_RESCHED:
 833		 */
 834		smp_mb();
 835	}
 836	if (!need_resched()) {
 837		idled = 1;
 838		ret = apm_bios_call_simple(APM_FUNC_IDLE, 0, 0, &eax, &err);
 839	}
 840	if (polling)
 841		current_thread_info()->status |= TS_POLLING;
 842
 843	if (!idled)
 844		return 0;
 845
 846	if (ret) {
 847		static unsigned long t;
 848
 849		/* This always fails on some SMP boards running UP kernels.
 850		 * Only report the failure the first 5 times.
 851		 */
 852		if (++t < 5) {
 853			printk(KERN_DEBUG "apm_do_idle failed (%d)\n", err);
 854			t = jiffies;
 855		}
 856		return -1;
 857	}
 858	clock_slowed = (apm_info.bios.flags & APM_IDLE_SLOWS_CLOCK) != 0;
 859	return clock_slowed;
 860}
 861
 862/**
 863 *	apm_do_busy	-	inform the BIOS the CPU is busy
 864 *
 865 *	Request that the BIOS brings the CPU back to full performance.
 866 */
 867
 868static void apm_do_busy(void)
 869{
 870	u32 dummy;
 871	int err;
 872
 873	if (clock_slowed || ALWAYS_CALL_BUSY) {
 874		(void)apm_bios_call_simple(APM_FUNC_BUSY, 0, 0, &dummy, &err);
 875		clock_slowed = 0;
 876	}
 877}
 878
 879/*
 880 * If no process has really been interested in
 881 * the CPU for some time, we want to call BIOS
 882 * power management - we probably want
 883 * to conserve power.
 884 */
 885#define IDLE_CALC_LIMIT	(HZ * 100)
 886#define IDLE_LEAKY_MAX	16
 887
 888static void (*original_pm_idle)(void) __read_mostly;
 889
 890/**
 891 * apm_cpu_idle		-	cpu idling for APM capable Linux
 892 *
 893 * This is the idling function the kernel executes when APM is available. It
 894 * tries to do BIOS powermanagement based on the average system idle time.
 895 * Furthermore it calls the system default idle routine.
 896 */
 897
 898static void apm_cpu_idle(void)
 
 899{
 900	static int use_apm_idle; /* = 0 */
 901	static unsigned int last_jiffies; /* = 0 */
 902	static unsigned int last_stime; /* = 0 */
 
 903
 904	int apm_idle_done = 0;
 905	unsigned int jiffies_since_last_check = jiffies - last_jiffies;
 906	unsigned int bucket;
 907
 908	WARN_ONCE(1, "deprecated apm_cpu_idle will be deleted in 2012");
 909recalc:
 
 910	if (jiffies_since_last_check > IDLE_CALC_LIMIT) {
 911		use_apm_idle = 0;
 912		last_jiffies = jiffies;
 913		last_stime = current->stime;
 914	} else if (jiffies_since_last_check > idle_period) {
 915		unsigned int idle_percentage;
 916
 917		idle_percentage = current->stime - last_stime;
 918		idle_percentage *= 100;
 919		idle_percentage /= jiffies_since_last_check;
 920		use_apm_idle = (idle_percentage > idle_threshold);
 921		if (apm_info.forbid_idle)
 922			use_apm_idle = 0;
 923		last_jiffies = jiffies;
 924		last_stime = current->stime;
 925	}
 926
 
 
 
 927	bucket = IDLE_LEAKY_MAX;
 928
 929	while (!need_resched()) {
 930		if (use_apm_idle) {
 931			unsigned int t;
 932
 933			t = jiffies;
 934			switch (apm_do_idle()) {
 935			case 0:
 936				apm_idle_done = 1;
 937				if (t != jiffies) {
 938					if (bucket) {
 939						bucket = IDLE_LEAKY_MAX;
 940						continue;
 941					}
 942				} else if (bucket) {
 943					bucket--;
 944					continue;
 945				}
 946				break;
 947			case 1:
 948				apm_idle_done = 1;
 949				break;
 950			default: /* BIOS refused */
 951				break;
 952			}
 953		}
 954		if (original_pm_idle)
 955			original_pm_idle();
 956		else
 957			default_idle();
 958		local_irq_disable();
 959		jiffies_since_last_check = jiffies - last_jiffies;
 960		if (jiffies_since_last_check > idle_period)
 961			goto recalc;
 962	}
 963
 964	if (apm_idle_done)
 965		apm_do_busy();
 966
 967	local_irq_enable();
 968}
 969
 970/**
 971 *	apm_power_off	-	ask the BIOS to power off
 972 *
 973 *	Handle the power off sequence. This is the one piece of code we
 974 *	will execute even on SMP machines. In order to deal with BIOS
 975 *	bugs we support real mode APM BIOS power off calls. We also make
 976 *	the SMP call on CPU0 as some systems will only honour this call
 977 *	on their first cpu.
 978 */
 979
 980static void apm_power_off(void)
 981{
 982	/* Some bioses don't like being called from CPU != 0 */
 983	if (apm_info.realmode_power_off) {
 984		set_cpus_allowed_ptr(current, cpumask_of(0));
 985		machine_real_restart(MRR_APM);
 986	} else {
 987		(void)set_system_power_state(APM_STATE_OFF);
 988	}
 989}
 990
 991#ifdef CONFIG_APM_DO_ENABLE
 992
 993/**
 994 *	apm_enable_power_management - enable BIOS APM power management
 995 *	@enable: enable yes/no
 996 *
 997 *	Enable or disable the APM BIOS power services.
 998 */
 999
1000static int apm_enable_power_management(int enable)
1001{
1002	u32 eax;
1003	int err;
1004
1005	if ((enable == 0) && (apm_info.bios.flags & APM_BIOS_DISENGAGED))
1006		return APM_NOT_ENGAGED;
1007	if (apm_bios_call_simple(APM_FUNC_ENABLE_PM, APM_DEVICE_BALL,
1008				 enable, &eax, &err))
1009		return err;
1010	if (enable)
1011		apm_info.bios.flags &= ~APM_BIOS_DISABLED;
1012	else
1013		apm_info.bios.flags |= APM_BIOS_DISABLED;
1014	return APM_SUCCESS;
1015}
1016#endif
1017
1018/**
1019 *	apm_get_power_status	-	get current power state
1020 *	@status: returned status
1021 *	@bat: battery info
1022 *	@life: estimated life
1023 *
1024 *	Obtain the current power status from the APM BIOS. We return a
1025 *	status which gives the rough battery status, and current power
1026 *	source. The bat value returned give an estimate as a percentage
1027 *	of life and a status value for the battery. The estimated life
1028 *	if reported is a lifetime in secodnds/minutes at current powwer
1029 *	consumption.
1030 */
1031
1032static int apm_get_power_status(u_short *status, u_short *bat, u_short *life)
1033{
1034	struct apm_bios_call call;
1035
1036	call.func = APM_FUNC_GET_STATUS;
1037	call.ebx = APM_DEVICE_ALL;
1038	call.ecx = 0;
1039
1040	if (apm_info.get_power_status_broken)
1041		return APM_32_UNSUPPORTED;
1042	if (apm_bios_call(&call))
1043		return call.err;
1044	*status = call.ebx;
1045	*bat = call.ecx;
1046	if (apm_info.get_power_status_swabinminutes) {
1047		*life = swab16((u16)call.edx);
1048		*life |= 0x8000;
1049	} else
1050		*life = call.edx;
1051	return APM_SUCCESS;
1052}
1053
1054#if 0
1055static int apm_get_battery_status(u_short which, u_short *status,
1056				  u_short *bat, u_short *life, u_short *nbat)
1057{
1058	u32 eax;
1059	u32 ebx;
1060	u32 ecx;
1061	u32 edx;
1062	u32 esi;
1063
1064	if (apm_info.connection_version < 0x0102) {
1065		/* pretend we only have one battery. */
1066		if (which != 1)
1067			return APM_BAD_DEVICE;
1068		*nbat = 1;
1069		return apm_get_power_status(status, bat, life);
1070	}
1071
1072	if (apm_bios_call(APM_FUNC_GET_STATUS, (0x8000 | (which)), 0, &eax,
1073			  &ebx, &ecx, &edx, &esi))
1074		return (eax >> 8) & 0xff;
1075	*status = ebx;
1076	*bat = ecx;
1077	*life = edx;
1078	*nbat = esi;
1079	return APM_SUCCESS;
1080}
1081#endif
1082
1083/**
1084 *	apm_engage_power_management	-	enable PM on a device
1085 *	@device: identity of device
1086 *	@enable: on/off
1087 *
1088 *	Activate or deactive power management on either a specific device
1089 *	or the entire system (%APM_DEVICE_ALL).
1090 */
1091
1092static int apm_engage_power_management(u_short device, int enable)
1093{
1094	u32 eax;
1095	int err;
1096
1097	if ((enable == 0) && (device == APM_DEVICE_ALL)
1098	    && (apm_info.bios.flags & APM_BIOS_DISABLED))
1099		return APM_DISABLED;
1100	if (apm_bios_call_simple(APM_FUNC_ENGAGE_PM, device, enable,
1101				 &eax, &err))
1102		return err;
1103	if (device == APM_DEVICE_ALL) {
1104		if (enable)
1105			apm_info.bios.flags &= ~APM_BIOS_DISENGAGED;
1106		else
1107			apm_info.bios.flags |= APM_BIOS_DISENGAGED;
1108	}
1109	return APM_SUCCESS;
1110}
1111
1112#if defined(CONFIG_APM_DISPLAY_BLANK) && defined(CONFIG_VT)
1113
1114/**
1115 *	apm_console_blank	-	blank the display
1116 *	@blank: on/off
1117 *
1118 *	Attempt to blank the console, firstly by blanking just video device
1119 *	zero, and if that fails (some BIOSes don't support it) then it blanks
1120 *	all video devices. Typically the BIOS will do laptop backlight and
1121 *	monitor powerdown for us.
1122 */
1123
1124static int apm_console_blank(int blank)
1125{
1126	int error = APM_NOT_ENGAGED; /* silence gcc */
1127	int i;
1128	u_short state;
1129	static const u_short dev[3] = { 0x100, 0x1FF, 0x101 };
1130
1131	state = blank ? APM_STATE_STANDBY : APM_STATE_READY;
1132
1133	for (i = 0; i < ARRAY_SIZE(dev); i++) {
1134		error = set_power_state(dev[i], state);
1135
1136		if ((error == APM_SUCCESS) || (error == APM_NO_ERROR))
1137			return 1;
1138
1139		if (error == APM_NOT_ENGAGED)
1140			break;
1141	}
1142
1143	if (error == APM_NOT_ENGAGED) {
1144		static int tried;
1145		int eng_error;
1146		if (tried++ == 0) {
1147			eng_error = apm_engage_power_management(APM_DEVICE_ALL, 1);
1148			if (eng_error) {
1149				apm_error("set display", error);
1150				apm_error("engage interface", eng_error);
1151				return 0;
1152			} else
1153				return apm_console_blank(blank);
1154		}
1155	}
1156	apm_error("set display", error);
1157	return 0;
1158}
1159#endif
1160
1161static int queue_empty(struct apm_user *as)
1162{
1163	return as->event_head == as->event_tail;
1164}
1165
1166static apm_event_t get_queued_event(struct apm_user *as)
1167{
1168	if (++as->event_tail >= APM_MAX_EVENTS)
1169		as->event_tail = 0;
1170	return as->events[as->event_tail];
1171}
1172
1173static void queue_event(apm_event_t event, struct apm_user *sender)
1174{
1175	struct apm_user *as;
1176
1177	spin_lock(&user_list_lock);
1178	if (user_list == NULL)
1179		goto out;
1180	for (as = user_list; as != NULL; as = as->next) {
1181		if ((as == sender) || (!as->reader))
1182			continue;
1183		if (++as->event_head >= APM_MAX_EVENTS)
1184			as->event_head = 0;
1185
1186		if (as->event_head == as->event_tail) {
1187			static int notified;
1188
1189			if (notified++ == 0)
1190			    printk(KERN_ERR "apm: an event queue overflowed\n");
1191			if (++as->event_tail >= APM_MAX_EVENTS)
1192				as->event_tail = 0;
1193		}
1194		as->events[as->event_head] = event;
1195		if (!as->suser || !as->writer)
1196			continue;
1197		switch (event) {
1198		case APM_SYS_SUSPEND:
1199		case APM_USER_SUSPEND:
1200			as->suspends_pending++;
1201			suspends_pending++;
1202			break;
1203
1204		case APM_SYS_STANDBY:
1205		case APM_USER_STANDBY:
1206			as->standbys_pending++;
1207			standbys_pending++;
1208			break;
1209		}
1210	}
1211	wake_up_interruptible(&apm_waitqueue);
1212out:
1213	spin_unlock(&user_list_lock);
1214}
1215
1216static void reinit_timer(void)
1217{
1218#ifdef INIT_TIMER_AFTER_SUSPEND
1219	unsigned long flags;
1220
1221	raw_spin_lock_irqsave(&i8253_lock, flags);
1222	/* set the clock to HZ */
1223	outb_p(0x34, PIT_MODE);		/* binary, mode 2, LSB/MSB, ch 0 */
1224	udelay(10);
1225	outb_p(LATCH & 0xff, PIT_CH0);	/* LSB */
1226	udelay(10);
1227	outb_p(LATCH >> 8, PIT_CH0);	/* MSB */
1228	udelay(10);
1229	raw_spin_unlock_irqrestore(&i8253_lock, flags);
1230#endif
1231}
1232
1233static int suspend(int vetoable)
1234{
1235	int err;
1236	struct apm_user	*as;
1237
1238	dpm_suspend_start(PMSG_SUSPEND);
1239
1240	dpm_suspend_noirq(PMSG_SUSPEND);
1241
1242	local_irq_disable();
1243	syscore_suspend();
1244
1245	local_irq_enable();
1246
1247	save_processor_state();
1248	err = set_system_power_state(APM_STATE_SUSPEND);
1249	ignore_normal_resume = 1;
1250	restore_processor_state();
1251
1252	local_irq_disable();
1253	reinit_timer();
1254
1255	if (err == APM_NO_ERROR)
1256		err = APM_SUCCESS;
1257	if (err != APM_SUCCESS)
1258		apm_error("suspend", err);
1259	err = (err == APM_SUCCESS) ? 0 : -EIO;
1260
1261	syscore_resume();
1262	local_irq_enable();
1263
1264	dpm_resume_noirq(PMSG_RESUME);
1265
1266	dpm_resume_end(PMSG_RESUME);
 
1267	queue_event(APM_NORMAL_RESUME, NULL);
1268	spin_lock(&user_list_lock);
1269	for (as = user_list; as != NULL; as = as->next) {
1270		as->suspend_wait = 0;
1271		as->suspend_result = err;
1272	}
1273	spin_unlock(&user_list_lock);
1274	wake_up_interruptible(&apm_suspend_waitqueue);
1275	return err;
1276}
1277
1278static void standby(void)
1279{
1280	int err;
1281
1282	dpm_suspend_noirq(PMSG_SUSPEND);
1283
1284	local_irq_disable();
1285	syscore_suspend();
1286	local_irq_enable();
1287
1288	err = set_system_power_state(APM_STATE_STANDBY);
1289	if ((err != APM_SUCCESS) && (err != APM_NO_ERROR))
1290		apm_error("standby", err);
1291
1292	local_irq_disable();
1293	syscore_resume();
1294	local_irq_enable();
1295
1296	dpm_resume_noirq(PMSG_RESUME);
1297}
1298
1299static apm_event_t get_event(void)
1300{
1301	int error;
1302	apm_event_t event = APM_NO_EVENTS; /* silence gcc */
1303	apm_eventinfo_t	info;
1304
1305	static int notified;
1306
1307	/* we don't use the eventinfo */
1308	error = apm_get_event(&event, &info);
1309	if (error == APM_SUCCESS)
1310		return event;
1311
1312	if ((error != APM_NO_EVENTS) && (notified++ == 0))
1313		apm_error("get_event", error);
1314
1315	return 0;
1316}
1317
1318static void check_events(void)
1319{
1320	apm_event_t event;
1321	static unsigned long last_resume;
1322	static int ignore_bounce;
1323
1324	while ((event = get_event()) != 0) {
1325		if (debug) {
1326			if (event <= NR_APM_EVENT_NAME)
1327				printk(KERN_DEBUG "apm: received %s notify\n",
1328				       apm_event_name[event - 1]);
1329			else
1330				printk(KERN_DEBUG "apm: received unknown "
1331				       "event 0x%02x\n", event);
1332		}
1333		if (ignore_bounce
1334		    && (time_after(jiffies, last_resume + bounce_interval)))
1335			ignore_bounce = 0;
1336
1337		switch (event) {
1338		case APM_SYS_STANDBY:
1339		case APM_USER_STANDBY:
1340			queue_event(event, NULL);
1341			if (standbys_pending <= 0)
1342				standby();
1343			break;
1344
1345		case APM_USER_SUSPEND:
1346#ifdef CONFIG_APM_IGNORE_USER_SUSPEND
1347			if (apm_info.connection_version > 0x100)
1348				set_system_power_state(APM_STATE_REJECT);
1349			break;
1350#endif
1351		case APM_SYS_SUSPEND:
1352			if (ignore_bounce) {
1353				if (apm_info.connection_version > 0x100)
1354					set_system_power_state(APM_STATE_REJECT);
1355				break;
1356			}
1357			/*
1358			 * If we are already processing a SUSPEND,
1359			 * then further SUSPEND events from the BIOS
1360			 * will be ignored.  We also return here to
1361			 * cope with the fact that the Thinkpads keep
1362			 * sending a SUSPEND event until something else
1363			 * happens!
1364			 */
1365			if (ignore_sys_suspend)
1366				return;
1367			ignore_sys_suspend = 1;
1368			queue_event(event, NULL);
1369			if (suspends_pending <= 0)
1370				(void) suspend(1);
1371			break;
1372
1373		case APM_NORMAL_RESUME:
1374		case APM_CRITICAL_RESUME:
1375		case APM_STANDBY_RESUME:
1376			ignore_sys_suspend = 0;
1377			last_resume = jiffies;
1378			ignore_bounce = 1;
1379			if ((event != APM_NORMAL_RESUME)
1380			    || (ignore_normal_resume == 0)) {
1381				dpm_resume_end(PMSG_RESUME);
1382				queue_event(event, NULL);
1383			}
1384			ignore_normal_resume = 0;
1385			break;
1386
1387		case APM_CAPABILITY_CHANGE:
1388		case APM_LOW_BATTERY:
1389		case APM_POWER_STATUS_CHANGE:
1390			queue_event(event, NULL);
1391			/* If needed, notify drivers here */
1392			break;
1393
1394		case APM_UPDATE_TIME:
1395			break;
1396
1397		case APM_CRITICAL_SUSPEND:
1398			/*
1399			 * We are not allowed to reject a critical suspend.
1400			 */
1401			(void)suspend(0);
1402			break;
1403		}
1404	}
1405}
1406
1407static void apm_event_handler(void)
1408{
1409	static int pending_count = 4;
1410	int err;
1411
1412	if ((standbys_pending > 0) || (suspends_pending > 0)) {
1413		if ((apm_info.connection_version > 0x100) &&
1414		    (pending_count-- <= 0)) {
1415			pending_count = 4;
1416			if (debug)
1417				printk(KERN_DEBUG "apm: setting state busy\n");
1418			err = set_system_power_state(APM_STATE_BUSY);
1419			if (err)
1420				apm_error("busy", err);
1421		}
1422	} else
1423		pending_count = 4;
1424	check_events();
1425}
1426
1427/*
1428 * This is the APM thread main loop.
1429 */
1430
1431static void apm_mainloop(void)
1432{
1433	DECLARE_WAITQUEUE(wait, current);
1434
1435	add_wait_queue(&apm_waitqueue, &wait);
1436	set_current_state(TASK_INTERRUPTIBLE);
1437	for (;;) {
1438		schedule_timeout(APM_CHECK_TIMEOUT);
1439		if (kthread_should_stop())
1440			break;
1441		/*
1442		 * Ok, check all events, check for idle (and mark us sleeping
1443		 * so as not to count towards the load average)..
1444		 */
1445		set_current_state(TASK_INTERRUPTIBLE);
1446		apm_event_handler();
1447	}
1448	remove_wait_queue(&apm_waitqueue, &wait);
1449}
1450
1451static int check_apm_user(struct apm_user *as, const char *func)
1452{
1453	if (as == NULL || as->magic != APM_BIOS_MAGIC) {
1454		printk(KERN_ERR "apm: %s passed bad filp\n", func);
1455		return 1;
1456	}
1457	return 0;
1458}
1459
1460static ssize_t do_read(struct file *fp, char __user *buf, size_t count, loff_t *ppos)
1461{
1462	struct apm_user *as;
1463	int i;
1464	apm_event_t event;
1465
1466	as = fp->private_data;
1467	if (check_apm_user(as, "read"))
1468		return -EIO;
1469	if ((int)count < sizeof(apm_event_t))
1470		return -EINVAL;
1471	if ((queue_empty(as)) && (fp->f_flags & O_NONBLOCK))
1472		return -EAGAIN;
1473	wait_event_interruptible(apm_waitqueue, !queue_empty(as));
1474	i = count;
1475	while ((i >= sizeof(event)) && !queue_empty(as)) {
1476		event = get_queued_event(as);
1477		if (copy_to_user(buf, &event, sizeof(event))) {
1478			if (i < count)
1479				break;
1480			return -EFAULT;
1481		}
1482		switch (event) {
1483		case APM_SYS_SUSPEND:
1484		case APM_USER_SUSPEND:
1485			as->suspends_read++;
1486			break;
1487
1488		case APM_SYS_STANDBY:
1489		case APM_USER_STANDBY:
1490			as->standbys_read++;
1491			break;
1492		}
1493		buf += sizeof(event);
1494		i -= sizeof(event);
1495	}
1496	if (i < count)
1497		return count - i;
1498	if (signal_pending(current))
1499		return -ERESTARTSYS;
1500	return 0;
1501}
1502
1503static unsigned int do_poll(struct file *fp, poll_table *wait)
1504{
1505	struct apm_user *as;
1506
1507	as = fp->private_data;
1508	if (check_apm_user(as, "poll"))
1509		return 0;
1510	poll_wait(fp, &apm_waitqueue, wait);
1511	if (!queue_empty(as))
1512		return POLLIN | POLLRDNORM;
1513	return 0;
1514}
1515
1516static long do_ioctl(struct file *filp, u_int cmd, u_long arg)
1517{
1518	struct apm_user *as;
1519	int ret;
1520
1521	as = filp->private_data;
1522	if (check_apm_user(as, "ioctl"))
1523		return -EIO;
1524	if (!as->suser || !as->writer)
1525		return -EPERM;
1526	switch (cmd) {
1527	case APM_IOC_STANDBY:
1528		mutex_lock(&apm_mutex);
1529		if (as->standbys_read > 0) {
1530			as->standbys_read--;
1531			as->standbys_pending--;
1532			standbys_pending--;
1533		} else
1534			queue_event(APM_USER_STANDBY, as);
1535		if (standbys_pending <= 0)
1536			standby();
1537		mutex_unlock(&apm_mutex);
1538		break;
1539	case APM_IOC_SUSPEND:
1540		mutex_lock(&apm_mutex);
1541		if (as->suspends_read > 0) {
1542			as->suspends_read--;
1543			as->suspends_pending--;
1544			suspends_pending--;
1545		} else
1546			queue_event(APM_USER_SUSPEND, as);
1547		if (suspends_pending <= 0) {
1548			ret = suspend(1);
1549			mutex_unlock(&apm_mutex);
1550		} else {
1551			as->suspend_wait = 1;
1552			mutex_unlock(&apm_mutex);
1553			wait_event_interruptible(apm_suspend_waitqueue,
1554					as->suspend_wait == 0);
1555			ret = as->suspend_result;
1556		}
1557		return ret;
1558	default:
1559		return -ENOTTY;
1560	}
1561	return 0;
1562}
1563
1564static int do_release(struct inode *inode, struct file *filp)
1565{
1566	struct apm_user *as;
1567
1568	as = filp->private_data;
1569	if (check_apm_user(as, "release"))
1570		return 0;
1571	filp->private_data = NULL;
1572	if (as->standbys_pending > 0) {
1573		standbys_pending -= as->standbys_pending;
1574		if (standbys_pending <= 0)
1575			standby();
1576	}
1577	if (as->suspends_pending > 0) {
1578		suspends_pending -= as->suspends_pending;
1579		if (suspends_pending <= 0)
1580			(void) suspend(1);
1581	}
1582	spin_lock(&user_list_lock);
1583	if (user_list == as)
1584		user_list = as->next;
1585	else {
1586		struct apm_user *as1;
1587
1588		for (as1 = user_list;
1589		     (as1 != NULL) && (as1->next != as);
1590		     as1 = as1->next)
1591			;
1592		if (as1 == NULL)
1593			printk(KERN_ERR "apm: filp not in user list\n");
1594		else
1595			as1->next = as->next;
1596	}
1597	spin_unlock(&user_list_lock);
1598	kfree(as);
1599	return 0;
1600}
1601
1602static int do_open(struct inode *inode, struct file *filp)
1603{
1604	struct apm_user *as;
1605
1606	as = kmalloc(sizeof(*as), GFP_KERNEL);
1607	if (as == NULL) {
1608		printk(KERN_ERR "apm: cannot allocate struct of size %d bytes\n",
1609		       sizeof(*as));
1610		return -ENOMEM;
1611	}
1612	as->magic = APM_BIOS_MAGIC;
1613	as->event_tail = as->event_head = 0;
1614	as->suspends_pending = as->standbys_pending = 0;
1615	as->suspends_read = as->standbys_read = 0;
1616	/*
1617	 * XXX - this is a tiny bit broken, when we consider BSD
1618	 * process accounting. If the device is opened by root, we
1619	 * instantly flag that we used superuser privs. Who knows,
1620	 * we might close the device immediately without doing a
1621	 * privileged operation -- cevans
1622	 */
1623	as->suser = capable(CAP_SYS_ADMIN);
1624	as->writer = (filp->f_mode & FMODE_WRITE) == FMODE_WRITE;
1625	as->reader = (filp->f_mode & FMODE_READ) == FMODE_READ;
1626	spin_lock(&user_list_lock);
1627	as->next = user_list;
1628	user_list = as;
1629	spin_unlock(&user_list_lock);
1630	filp->private_data = as;
1631	return 0;
1632}
1633
1634static int proc_apm_show(struct seq_file *m, void *v)
1635{
1636	unsigned short	bx;
1637	unsigned short	cx;
1638	unsigned short	dx;
1639	int		error;
1640	unsigned short  ac_line_status = 0xff;
1641	unsigned short  battery_status = 0xff;
1642	unsigned short  battery_flag   = 0xff;
1643	int		percentage     = -1;
1644	int             time_units     = -1;
1645	char            *units         = "?";
1646
1647	if ((num_online_cpus() == 1) &&
1648	    !(error = apm_get_power_status(&bx, &cx, &dx))) {
1649		ac_line_status = (bx >> 8) & 0xff;
1650		battery_status = bx & 0xff;
1651		if ((cx & 0xff) != 0xff)
1652			percentage = cx & 0xff;
1653
1654		if (apm_info.connection_version > 0x100) {
1655			battery_flag = (cx >> 8) & 0xff;
1656			if (dx != 0xffff) {
1657				units = (dx & 0x8000) ? "min" : "sec";
1658				time_units = dx & 0x7fff;
1659			}
1660		}
1661	}
1662	/* Arguments, with symbols from linux/apm_bios.h.  Information is
1663	   from the Get Power Status (0x0a) call unless otherwise noted.
1664
1665	   0) Linux driver version (this will change if format changes)
1666	   1) APM BIOS Version.  Usually 1.0, 1.1 or 1.2.
1667	   2) APM flags from APM Installation Check (0x00):
1668	      bit 0: APM_16_BIT_SUPPORT
1669	      bit 1: APM_32_BIT_SUPPORT
1670	      bit 2: APM_IDLE_SLOWS_CLOCK
1671	      bit 3: APM_BIOS_DISABLED
1672	      bit 4: APM_BIOS_DISENGAGED
1673	   3) AC line status
1674	      0x00: Off-line
1675	      0x01: On-line
1676	      0x02: On backup power (BIOS >= 1.1 only)
1677	      0xff: Unknown
1678	   4) Battery status
1679	      0x00: High
1680	      0x01: Low
1681	      0x02: Critical
1682	      0x03: Charging
1683	      0x04: Selected battery not present (BIOS >= 1.2 only)
1684	      0xff: Unknown
1685	   5) Battery flag
1686	      bit 0: High
1687	      bit 1: Low
1688	      bit 2: Critical
1689	      bit 3: Charging
1690	      bit 7: No system battery
1691	      0xff: Unknown
1692	   6) Remaining battery life (percentage of charge):
1693	      0-100: valid
1694	      -1: Unknown
1695	   7) Remaining battery life (time units):
1696	      Number of remaining minutes or seconds
1697	      -1: Unknown
1698	   8) min = minutes; sec = seconds */
1699
1700	seq_printf(m, "%s %d.%d 0x%02x 0x%02x 0x%02x 0x%02x %d%% %d %s\n",
1701		   driver_version,
1702		   (apm_info.bios.version >> 8) & 0xff,
1703		   apm_info.bios.version & 0xff,
1704		   apm_info.bios.flags,
1705		   ac_line_status,
1706		   battery_status,
1707		   battery_flag,
1708		   percentage,
1709		   time_units,
1710		   units);
1711	return 0;
1712}
1713
1714static int proc_apm_open(struct inode *inode, struct file *file)
1715{
1716	return single_open(file, proc_apm_show, NULL);
1717}
1718
1719static const struct file_operations apm_file_ops = {
1720	.owner		= THIS_MODULE,
1721	.open		= proc_apm_open,
1722	.read		= seq_read,
1723	.llseek		= seq_lseek,
1724	.release	= single_release,
1725};
1726
1727static int apm(void *unused)
1728{
1729	unsigned short	bx;
1730	unsigned short	cx;
1731	unsigned short	dx;
1732	int		error;
1733	char 		*power_stat;
1734	char 		*bat_stat;
1735
1736	/* 2002/08/01 - WT
1737	 * This is to avoid random crashes at boot time during initialization
1738	 * on SMP systems in case of "apm=power-off" mode. Seen on ASUS A7M266D.
1739	 * Some bioses don't like being called from CPU != 0.
1740	 * Method suggested by Ingo Molnar.
1741	 */
1742	set_cpus_allowed_ptr(current, cpumask_of(0));
1743	BUG_ON(smp_processor_id() != 0);
1744
1745	if (apm_info.connection_version == 0) {
1746		apm_info.connection_version = apm_info.bios.version;
1747		if (apm_info.connection_version > 0x100) {
1748			/*
1749			 * We only support BIOSs up to version 1.2
1750			 */
1751			if (apm_info.connection_version > 0x0102)
1752				apm_info.connection_version = 0x0102;
1753			error = apm_driver_version(&apm_info.connection_version);
1754			if (error != APM_SUCCESS) {
1755				apm_error("driver version", error);
1756				/* Fall back to an APM 1.0 connection. */
1757				apm_info.connection_version = 0x100;
1758			}
1759		}
1760	}
1761
1762	if (debug)
1763		printk(KERN_INFO "apm: Connection version %d.%d\n",
1764			(apm_info.connection_version >> 8) & 0xff,
1765			apm_info.connection_version & 0xff);
1766
1767#ifdef CONFIG_APM_DO_ENABLE
1768	if (apm_info.bios.flags & APM_BIOS_DISABLED) {
1769		/*
1770		 * This call causes my NEC UltraLite Versa 33/C to hang if it
1771		 * is booted with PM disabled but not in the docking station.
1772		 * Unfortunate ...
1773		 */
1774		error = apm_enable_power_management(1);
1775		if (error) {
1776			apm_error("enable power management", error);
1777			return -1;
1778		}
1779	}
1780#endif
1781
1782	if ((apm_info.bios.flags & APM_BIOS_DISENGAGED)
1783	    && (apm_info.connection_version > 0x0100)) {
1784		error = apm_engage_power_management(APM_DEVICE_ALL, 1);
1785		if (error) {
1786			apm_error("engage power management", error);
1787			return -1;
1788		}
1789	}
1790
1791	if (debug && (num_online_cpus() == 1 || smp)) {
1792		error = apm_get_power_status(&bx, &cx, &dx);
1793		if (error)
1794			printk(KERN_INFO "apm: power status not available\n");
1795		else {
1796			switch ((bx >> 8) & 0xff) {
1797			case 0:
1798				power_stat = "off line";
1799				break;
1800			case 1:
1801				power_stat = "on line";
1802				break;
1803			case 2:
1804				power_stat = "on backup power";
1805				break;
1806			default:
1807				power_stat = "unknown";
1808				break;
1809			}
1810			switch (bx & 0xff) {
1811			case 0:
1812				bat_stat = "high";
1813				break;
1814			case 1:
1815				bat_stat = "low";
1816				break;
1817			case 2:
1818				bat_stat = "critical";
1819				break;
1820			case 3:
1821				bat_stat = "charging";
1822				break;
1823			default:
1824				bat_stat = "unknown";
1825				break;
1826			}
1827			printk(KERN_INFO
1828			       "apm: AC %s, battery status %s, battery life ",
1829			       power_stat, bat_stat);
1830			if ((cx & 0xff) == 0xff)
1831				printk("unknown\n");
1832			else
1833				printk("%d%%\n", cx & 0xff);
1834			if (apm_info.connection_version > 0x100) {
1835				printk(KERN_INFO
1836				       "apm: battery flag 0x%02x, battery life ",
1837				       (cx >> 8) & 0xff);
1838				if (dx == 0xffff)
1839					printk("unknown\n");
1840				else
1841					printk("%d %s\n", dx & 0x7fff,
1842					       (dx & 0x8000) ?
1843					       "minutes" : "seconds");
1844			}
1845		}
1846	}
1847
1848	/* Install our power off handler.. */
1849	if (power_off)
1850		pm_power_off = apm_power_off;
1851
1852	if (num_online_cpus() == 1 || smp) {
1853#if defined(CONFIG_APM_DISPLAY_BLANK) && defined(CONFIG_VT)
1854		console_blank_hook = apm_console_blank;
1855#endif
1856		apm_mainloop();
1857#if defined(CONFIG_APM_DISPLAY_BLANK) && defined(CONFIG_VT)
1858		console_blank_hook = NULL;
1859#endif
1860	}
1861
1862	return 0;
1863}
1864
1865#ifndef MODULE
1866static int __init apm_setup(char *str)
1867{
1868	int invert;
1869
1870	while ((str != NULL) && (*str != '\0')) {
1871		if (strncmp(str, "off", 3) == 0)
1872			apm_disabled = 1;
1873		if (strncmp(str, "on", 2) == 0)
1874			apm_disabled = 0;
1875		if ((strncmp(str, "bounce-interval=", 16) == 0) ||
1876		    (strncmp(str, "bounce_interval=", 16) == 0))
1877			bounce_interval = simple_strtol(str + 16, NULL, 0);
1878		if ((strncmp(str, "idle-threshold=", 15) == 0) ||
1879		    (strncmp(str, "idle_threshold=", 15) == 0))
1880			idle_threshold = simple_strtol(str + 15, NULL, 0);
1881		if ((strncmp(str, "idle-period=", 12) == 0) ||
1882		    (strncmp(str, "idle_period=", 12) == 0))
1883			idle_period = simple_strtol(str + 12, NULL, 0);
1884		invert = (strncmp(str, "no-", 3) == 0) ||
1885			(strncmp(str, "no_", 3) == 0);
1886		if (invert)
1887			str += 3;
1888		if (strncmp(str, "debug", 5) == 0)
1889			debug = !invert;
1890		if ((strncmp(str, "power-off", 9) == 0) ||
1891		    (strncmp(str, "power_off", 9) == 0))
1892			power_off = !invert;
1893		if (strncmp(str, "smp", 3) == 0) {
1894			smp = !invert;
1895			idle_threshold = 100;
1896		}
1897		if ((strncmp(str, "allow-ints", 10) == 0) ||
1898		    (strncmp(str, "allow_ints", 10) == 0))
1899			apm_info.allow_ints = !invert;
1900		if ((strncmp(str, "broken-psr", 10) == 0) ||
1901		    (strncmp(str, "broken_psr", 10) == 0))
1902			apm_info.get_power_status_broken = !invert;
1903		if ((strncmp(str, "realmode-power-off", 18) == 0) ||
1904		    (strncmp(str, "realmode_power_off", 18) == 0))
1905			apm_info.realmode_power_off = !invert;
1906		str = strchr(str, ',');
1907		if (str != NULL)
1908			str += strspn(str, ", \t");
1909	}
1910	return 1;
1911}
1912
1913__setup("apm=", apm_setup);
1914#endif
1915
1916static const struct file_operations apm_bios_fops = {
1917	.owner		= THIS_MODULE,
1918	.read		= do_read,
1919	.poll		= do_poll,
1920	.unlocked_ioctl	= do_ioctl,
1921	.open		= do_open,
1922	.release	= do_release,
1923	.llseek		= noop_llseek,
1924};
1925
1926static struct miscdevice apm_device = {
1927	APM_MINOR_DEV,
1928	"apm_bios",
1929	&apm_bios_fops
1930};
1931
1932
1933/* Simple "print if true" callback */
1934static int __init print_if_true(const struct dmi_system_id *d)
1935{
1936	printk("%s\n", d->ident);
1937	return 0;
1938}
1939
1940/*
1941 * Some Bioses enable the PS/2 mouse (touchpad) at resume, even if it was
1942 * disabled before the suspend. Linux used to get terribly confused by that.
1943 */
1944static int __init broken_ps2_resume(const struct dmi_system_id *d)
1945{
1946	printk(KERN_INFO "%s machine detected. Mousepad Resume Bug "
1947	       "workaround hopefully not needed.\n", d->ident);
1948	return 0;
1949}
1950
1951/* Some bioses have a broken protected mode poweroff and need to use realmode */
1952static int __init set_realmode_power_off(const struct dmi_system_id *d)
1953{
1954	if (apm_info.realmode_power_off == 0) {
1955		apm_info.realmode_power_off = 1;
1956		printk(KERN_INFO "%s bios detected. "
1957		       "Using realmode poweroff only.\n", d->ident);
1958	}
1959	return 0;
1960}
1961
1962/* Some laptops require interrupts to be enabled during APM calls */
1963static int __init set_apm_ints(const struct dmi_system_id *d)
1964{
1965	if (apm_info.allow_ints == 0) {
1966		apm_info.allow_ints = 1;
1967		printk(KERN_INFO "%s machine detected. "
1968		       "Enabling interrupts during APM calls.\n", d->ident);
1969	}
1970	return 0;
1971}
1972
1973/* Some APM bioses corrupt memory or just plain do not work */
1974static int __init apm_is_horked(const struct dmi_system_id *d)
1975{
1976	if (apm_info.disabled == 0) {
1977		apm_info.disabled = 1;
1978		printk(KERN_INFO "%s machine detected. "
1979		       "Disabling APM.\n", d->ident);
1980	}
1981	return 0;
1982}
1983
1984static int __init apm_is_horked_d850md(const struct dmi_system_id *d)
1985{
1986	if (apm_info.disabled == 0) {
1987		apm_info.disabled = 1;
1988		printk(KERN_INFO "%s machine detected. "
1989		       "Disabling APM.\n", d->ident);
1990		printk(KERN_INFO "This bug is fixed in bios P15 which is available for\n");
1991		printk(KERN_INFO "download from support.intel.com\n");
1992	}
1993	return 0;
1994}
1995
1996/* Some APM bioses hang on APM idle calls */
1997static int __init apm_likes_to_melt(const struct dmi_system_id *d)
1998{
1999	if (apm_info.forbid_idle == 0) {
2000		apm_info.forbid_idle = 1;
2001		printk(KERN_INFO "%s machine detected. "
2002		       "Disabling APM idle calls.\n", d->ident);
2003	}
2004	return 0;
2005}
2006
2007/*
2008 *  Check for clue free BIOS implementations who use
2009 *  the following QA technique
2010 *
2011 *      [ Write BIOS Code ]<------
2012 *               |                ^
2013 *      < Does it Compile >----N--
2014 *               |Y               ^
2015 *	< Does it Boot Win98 >-N--
2016 *               |Y
2017 *           [Ship It]
2018 *
2019 *	Phoenix A04  08/24/2000 is known bad (Dell Inspiron 5000e)
2020 *	Phoenix A07  09/29/2000 is known good (Dell Inspiron 5000)
2021 */
2022static int __init broken_apm_power(const struct dmi_system_id *d)
2023{
2024	apm_info.get_power_status_broken = 1;
2025	printk(KERN_WARNING "BIOS strings suggest APM bugs, "
2026	       "disabling power status reporting.\n");
2027	return 0;
2028}
2029
2030/*
2031 * This bios swaps the APM minute reporting bytes over (Many sony laptops
2032 * have this problem).
2033 */
2034static int __init swab_apm_power_in_minutes(const struct dmi_system_id *d)
2035{
2036	apm_info.get_power_status_swabinminutes = 1;
2037	printk(KERN_WARNING "BIOS strings suggest APM reports battery life "
2038	       "in minutes and wrong byte order.\n");
2039	return 0;
2040}
2041
2042static struct dmi_system_id __initdata apm_dmi_table[] = {
2043	{
2044		print_if_true,
2045		KERN_WARNING "IBM T23 - BIOS 1.03b+ and controller firmware 1.02+ may be needed for Linux APM.",
2046		{	DMI_MATCH(DMI_SYS_VENDOR, "IBM"),
2047			DMI_MATCH(DMI_BIOS_VERSION, "1AET38WW (1.01b)"), },
2048	},
2049	{	/* Handle problems with APM on the C600 */
2050		broken_ps2_resume, "Dell Latitude C600",
2051		{	DMI_MATCH(DMI_SYS_VENDOR, "Dell"),
2052			DMI_MATCH(DMI_PRODUCT_NAME, "Latitude C600"), },
2053	},
2054	{	/* Allow interrupts during suspend on Dell Latitude laptops*/
2055		set_apm_ints, "Dell Latitude",
2056		{	DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
2057			DMI_MATCH(DMI_PRODUCT_NAME, "Latitude C510"), }
2058	},
2059	{	/* APM crashes */
2060		apm_is_horked, "Dell Inspiron 2500",
2061		{	DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
2062			DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 2500"),
2063			DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2064			DMI_MATCH(DMI_BIOS_VERSION, "A11"), },
2065	},
2066	{	/* Allow interrupts during suspend on Dell Inspiron laptops*/
2067		set_apm_ints, "Dell Inspiron", {
2068			DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
2069			DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 4000"), },
2070	},
2071	{	/* Handle problems with APM on Inspiron 5000e */
2072		broken_apm_power, "Dell Inspiron 5000e",
2073		{	DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2074			DMI_MATCH(DMI_BIOS_VERSION, "A04"),
2075			DMI_MATCH(DMI_BIOS_DATE, "08/24/2000"), },
2076	},
2077	{	/* Handle problems with APM on Inspiron 2500 */
2078		broken_apm_power, "Dell Inspiron 2500",
2079		{	DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2080			DMI_MATCH(DMI_BIOS_VERSION, "A12"),
2081			DMI_MATCH(DMI_BIOS_DATE, "02/04/2002"), },
2082	},
2083	{	/* APM crashes */
2084		apm_is_horked, "Dell Dimension 4100",
2085		{	DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
2086			DMI_MATCH(DMI_PRODUCT_NAME, "XPS-Z"),
2087			DMI_MATCH(DMI_BIOS_VENDOR, "Intel Corp."),
2088			DMI_MATCH(DMI_BIOS_VERSION, "A11"), },
2089	},
2090	{	/* Allow interrupts during suspend on Compaq Laptops*/
2091		set_apm_ints, "Compaq 12XL125",
2092		{	DMI_MATCH(DMI_SYS_VENDOR, "Compaq"),
2093			DMI_MATCH(DMI_PRODUCT_NAME, "Compaq PC"),
2094			DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2095			DMI_MATCH(DMI_BIOS_VERSION, "4.06"), },
2096	},
2097	{	/* Allow interrupts during APM or the clock goes slow */
2098		set_apm_ints, "ASUSTeK",
2099		{	DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK Computer Inc."),
2100			DMI_MATCH(DMI_PRODUCT_NAME, "L8400K series Notebook PC"), },
2101	},
2102	{	/* APM blows on shutdown */
2103		apm_is_horked, "ABIT KX7-333[R]",
2104		{	DMI_MATCH(DMI_BOARD_VENDOR, "ABIT"),
2105			DMI_MATCH(DMI_BOARD_NAME, "VT8367-8233A (KX7-333[R])"), },
2106	},
2107	{	/* APM crashes */
2108		apm_is_horked, "Trigem Delhi3",
2109		{	DMI_MATCH(DMI_SYS_VENDOR, "TriGem Computer, Inc"),
2110			DMI_MATCH(DMI_PRODUCT_NAME, "Delhi3"), },
2111	},
2112	{	/* APM crashes */
2113		apm_is_horked, "Fujitsu-Siemens",
2114		{	DMI_MATCH(DMI_BIOS_VENDOR, "hoenix/FUJITSU SIEMENS"),
2115			DMI_MATCH(DMI_BIOS_VERSION, "Version1.01"), },
2116	},
2117	{	/* APM crashes */
2118		apm_is_horked_d850md, "Intel D850MD",
2119		{	DMI_MATCH(DMI_BIOS_VENDOR, "Intel Corp."),
2120			DMI_MATCH(DMI_BIOS_VERSION, "MV85010A.86A.0016.P07.0201251536"), },
2121	},
2122	{	/* APM crashes */
2123		apm_is_horked, "Intel D810EMO",
2124		{	DMI_MATCH(DMI_BIOS_VENDOR, "Intel Corp."),
2125			DMI_MATCH(DMI_BIOS_VERSION, "MO81010A.86A.0008.P04.0004170800"), },
2126	},
2127	{	/* APM crashes */
2128		apm_is_horked, "Dell XPS-Z",
2129		{	DMI_MATCH(DMI_BIOS_VENDOR, "Intel Corp."),
2130			DMI_MATCH(DMI_BIOS_VERSION, "A11"),
2131			DMI_MATCH(DMI_PRODUCT_NAME, "XPS-Z"), },
2132	},
2133	{	/* APM crashes */
2134		apm_is_horked, "Sharp PC-PJ/AX",
2135		{	DMI_MATCH(DMI_SYS_VENDOR, "SHARP"),
2136			DMI_MATCH(DMI_PRODUCT_NAME, "PC-PJ/AX"),
2137			DMI_MATCH(DMI_BIOS_VENDOR, "SystemSoft"),
2138			DMI_MATCH(DMI_BIOS_VERSION, "Version R2.08"), },
2139	},
2140	{	/* APM crashes */
2141		apm_is_horked, "Dell Inspiron 2500",
2142		{	DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
2143			DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 2500"),
2144			DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2145			DMI_MATCH(DMI_BIOS_VERSION, "A11"), },
2146	},
2147	{	/* APM idle hangs */
2148		apm_likes_to_melt, "Jabil AMD",
2149		{	DMI_MATCH(DMI_BIOS_VENDOR, "American Megatrends Inc."),
2150			DMI_MATCH(DMI_BIOS_VERSION, "0AASNP06"), },
2151	},
2152	{	/* APM idle hangs */
2153		apm_likes_to_melt, "AMI Bios",
2154		{	DMI_MATCH(DMI_BIOS_VENDOR, "American Megatrends Inc."),
2155			DMI_MATCH(DMI_BIOS_VERSION, "0AASNP05"), },
2156	},
2157	{	/* Handle problems with APM on Sony Vaio PCG-N505X(DE) */
2158		swab_apm_power_in_minutes, "Sony VAIO",
2159		{	DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2160			DMI_MATCH(DMI_BIOS_VERSION, "R0206H"),
2161			DMI_MATCH(DMI_BIOS_DATE, "08/23/99"), },
2162	},
2163	{	/* Handle problems with APM on Sony Vaio PCG-N505VX */
2164		swab_apm_power_in_minutes, "Sony VAIO",
2165		{	DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2166			DMI_MATCH(DMI_BIOS_VERSION, "W2K06H0"),
2167			DMI_MATCH(DMI_BIOS_DATE, "02/03/00"), },
2168	},
2169	{	/* Handle problems with APM on Sony Vaio PCG-XG29 */
2170		swab_apm_power_in_minutes, "Sony VAIO",
2171		{	DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2172			DMI_MATCH(DMI_BIOS_VERSION, "R0117A0"),
2173			DMI_MATCH(DMI_BIOS_DATE, "04/25/00"), },
2174	},
2175	{	/* Handle problems with APM on Sony Vaio PCG-Z600NE */
2176		swab_apm_power_in_minutes, "Sony VAIO",
2177		{	DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2178			DMI_MATCH(DMI_BIOS_VERSION, "R0121Z1"),
2179			DMI_MATCH(DMI_BIOS_DATE, "05/11/00"), },
2180	},
2181	{	/* Handle problems with APM on Sony Vaio PCG-Z600NE */
2182		swab_apm_power_in_minutes, "Sony VAIO",
2183		{	DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2184			DMI_MATCH(DMI_BIOS_VERSION, "WME01Z1"),
2185			DMI_MATCH(DMI_BIOS_DATE, "08/11/00"), },
2186	},
2187	{	/* Handle problems with APM on Sony Vaio PCG-Z600LEK(DE) */
2188		swab_apm_power_in_minutes, "Sony VAIO",
2189		{	DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2190			DMI_MATCH(DMI_BIOS_VERSION, "R0206Z3"),
2191			DMI_MATCH(DMI_BIOS_DATE, "12/25/00"), },
2192	},
2193	{	/* Handle problems with APM on Sony Vaio PCG-Z505LS */
2194		swab_apm_power_in_minutes, "Sony VAIO",
2195		{	DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2196			DMI_MATCH(DMI_BIOS_VERSION, "R0203D0"),
2197			DMI_MATCH(DMI_BIOS_DATE, "05/12/00"), },
2198	},
2199	{	/* Handle problems with APM on Sony Vaio PCG-Z505LS */
2200		swab_apm_power_in_minutes, "Sony VAIO",
2201		{	DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2202			DMI_MATCH(DMI_BIOS_VERSION, "R0203Z3"),
2203			DMI_MATCH(DMI_BIOS_DATE, "08/25/00"), },
2204	},
2205	{	/* Handle problems with APM on Sony Vaio PCG-Z505LS (with updated BIOS) */
2206		swab_apm_power_in_minutes, "Sony VAIO",
2207		{	DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2208			DMI_MATCH(DMI_BIOS_VERSION, "R0209Z3"),
2209			DMI_MATCH(DMI_BIOS_DATE, "05/12/01"), },
2210	},
2211	{	/* Handle problems with APM on Sony Vaio PCG-F104K */
2212		swab_apm_power_in_minutes, "Sony VAIO",
2213		{	DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2214			DMI_MATCH(DMI_BIOS_VERSION, "R0204K2"),
2215			DMI_MATCH(DMI_BIOS_DATE, "08/28/00"), },
2216	},
2217
2218	{	/* Handle problems with APM on Sony Vaio PCG-C1VN/C1VE */
2219		swab_apm_power_in_minutes, "Sony VAIO",
2220		{	DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2221			DMI_MATCH(DMI_BIOS_VERSION, "R0208P1"),
2222			DMI_MATCH(DMI_BIOS_DATE, "11/09/00"), },
2223	},
2224	{	/* Handle problems with APM on Sony Vaio PCG-C1VE */
2225		swab_apm_power_in_minutes, "Sony VAIO",
2226		{	DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2227			DMI_MATCH(DMI_BIOS_VERSION, "R0204P1"),
2228			DMI_MATCH(DMI_BIOS_DATE, "09/12/00"), },
2229	},
2230	{	/* Handle problems with APM on Sony Vaio PCG-C1VE */
2231		swab_apm_power_in_minutes, "Sony VAIO",
2232		{	DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2233			DMI_MATCH(DMI_BIOS_VERSION, "WXPO1Z3"),
2234			DMI_MATCH(DMI_BIOS_DATE, "10/26/01"), },
2235	},
2236	{	/* broken PM poweroff bios */
2237		set_realmode_power_off, "Award Software v4.60 PGMA",
2238		{	DMI_MATCH(DMI_BIOS_VENDOR, "Award Software International, Inc."),
2239			DMI_MATCH(DMI_BIOS_VERSION, "4.60 PGMA"),
2240			DMI_MATCH(DMI_BIOS_DATE, "134526184"), },
2241	},
2242
2243	/* Generic per vendor APM settings  */
2244
2245	{	/* Allow interrupts during suspend on IBM laptops */
2246		set_apm_ints, "IBM",
2247		{	DMI_MATCH(DMI_SYS_VENDOR, "IBM"), },
2248	},
2249
2250	{ }
2251};
2252
2253/*
2254 * Just start the APM thread. We do NOT want to do APM BIOS
2255 * calls from anything but the APM thread, if for no other reason
2256 * than the fact that we don't trust the APM BIOS. This way,
2257 * most common APM BIOS problems that lead to protection errors
2258 * etc will have at least some level of being contained...
2259 *
2260 * In short, if something bad happens, at least we have a choice
2261 * of just killing the apm thread..
2262 */
2263static int __init apm_init(void)
2264{
2265	struct desc_struct *gdt;
2266	int err;
2267
2268	dmi_check_system(apm_dmi_table);
2269
2270	if (apm_info.bios.version == 0 || paravirt_enabled() || machine_is_olpc()) {
2271		printk(KERN_INFO "apm: BIOS not found.\n");
2272		return -ENODEV;
2273	}
2274	printk(KERN_INFO
2275	       "apm: BIOS version %d.%d Flags 0x%02x (Driver version %s)\n",
2276	       ((apm_info.bios.version >> 8) & 0xff),
2277	       (apm_info.bios.version & 0xff),
2278	       apm_info.bios.flags,
2279	       driver_version);
2280	if ((apm_info.bios.flags & APM_32_BIT_SUPPORT) == 0) {
2281		printk(KERN_INFO "apm: no 32 bit BIOS support\n");
2282		return -ENODEV;
2283	}
2284
2285	if (allow_ints)
2286		apm_info.allow_ints = 1;
2287	if (broken_psr)
2288		apm_info.get_power_status_broken = 1;
2289	if (realmode_power_off)
2290		apm_info.realmode_power_off = 1;
2291	/* User can override, but default is to trust DMI */
2292	if (apm_disabled != -1)
2293		apm_info.disabled = apm_disabled;
2294
2295	/*
2296	 * Fix for the Compaq Contura 3/25c which reports BIOS version 0.1
2297	 * but is reportedly a 1.0 BIOS.
2298	 */
2299	if (apm_info.bios.version == 0x001)
2300		apm_info.bios.version = 0x100;
2301
2302	/* BIOS < 1.2 doesn't set cseg_16_len */
2303	if (apm_info.bios.version < 0x102)
2304		apm_info.bios.cseg_16_len = 0; /* 64k */
2305
2306	if (debug) {
2307		printk(KERN_INFO "apm: entry %x:%x cseg16 %x dseg %x",
2308			apm_info.bios.cseg, apm_info.bios.offset,
2309			apm_info.bios.cseg_16, apm_info.bios.dseg);
2310		if (apm_info.bios.version > 0x100)
2311			printk(" cseg len %x, dseg len %x",
2312				apm_info.bios.cseg_len,
2313				apm_info.bios.dseg_len);
2314		if (apm_info.bios.version > 0x101)
2315			printk(" cseg16 len %x", apm_info.bios.cseg_16_len);
2316		printk("\n");
2317	}
2318
2319	if (apm_info.disabled) {
2320		printk(KERN_NOTICE "apm: disabled on user request.\n");
2321		return -ENODEV;
2322	}
2323	if ((num_online_cpus() > 1) && !power_off && !smp) {
2324		printk(KERN_NOTICE "apm: disabled - APM is not SMP safe.\n");
2325		apm_info.disabled = 1;
2326		return -ENODEV;
2327	}
2328	if (!acpi_disabled) {
2329		printk(KERN_NOTICE "apm: overridden by ACPI.\n");
2330		apm_info.disabled = 1;
2331		return -ENODEV;
2332	}
2333
2334	/*
2335	 * Set up the long jump entry point to the APM BIOS, which is called
2336	 * from inline assembly.
2337	 */
2338	apm_bios_entry.offset = apm_info.bios.offset;
2339	apm_bios_entry.segment = APM_CS;
2340
2341	/*
2342	 * The APM 1.1 BIOS is supposed to provide limit information that it
2343	 * recognizes.  Many machines do this correctly, but many others do
2344	 * not restrict themselves to their claimed limit.  When this happens,
2345	 * they will cause a segmentation violation in the kernel at boot time.
2346	 * Most BIOS's, however, will respect a 64k limit, so we use that.
2347	 *
2348	 * Note we only set APM segments on CPU zero, since we pin the APM
2349	 * code to that CPU.
2350	 */
2351	gdt = get_cpu_gdt_table(0);
2352	set_desc_base(&gdt[APM_CS >> 3],
2353		 (unsigned long)__va((unsigned long)apm_info.bios.cseg << 4));
2354	set_desc_base(&gdt[APM_CS_16 >> 3],
2355		 (unsigned long)__va((unsigned long)apm_info.bios.cseg_16 << 4));
2356	set_desc_base(&gdt[APM_DS >> 3],
2357		 (unsigned long)__va((unsigned long)apm_info.bios.dseg << 4));
2358
2359	proc_create("apm", 0, NULL, &apm_file_ops);
2360
2361	kapmd_task = kthread_create(apm, NULL, "kapmd");
2362	if (IS_ERR(kapmd_task)) {
2363		printk(KERN_ERR "apm: disabled - Unable to start kernel "
2364				"thread.\n");
2365		err = PTR_ERR(kapmd_task);
2366		kapmd_task = NULL;
2367		remove_proc_entry("apm", NULL);
2368		return err;
2369	}
2370	wake_up_process(kapmd_task);
2371
2372	if (num_online_cpus() > 1 && !smp) {
2373		printk(KERN_NOTICE
2374		       "apm: disabled - APM is not SMP safe (power off active).\n");
2375		return 0;
2376	}
2377
2378	/*
2379	 * Note we don't actually care if the misc_device cannot be registered.
2380	 * this driver can do its job without it, even if userspace can't
2381	 * control it.  just log the error
2382	 */
2383	if (misc_register(&apm_device))
2384		printk(KERN_WARNING "apm: Could not register misc device.\n");
2385
2386	if (HZ != 100)
2387		idle_period = (idle_period * HZ) / 100;
2388	if (idle_threshold < 100) {
2389		original_pm_idle = pm_idle;
2390		pm_idle  = apm_cpu_idle;
2391		set_pm_idle = 1;
2392	}
2393
2394	return 0;
2395}
2396
2397static void __exit apm_exit(void)
2398{
2399	int error;
2400
2401	if (set_pm_idle) {
2402		pm_idle = original_pm_idle;
2403		/*
2404		 * We are about to unload the current idle thread pm callback
2405		 * (pm_idle), Wait for all processors to update cached/local
2406		 * copies of pm_idle before proceeding.
2407		 */
2408		cpu_idle_wait();
2409	}
2410	if (((apm_info.bios.flags & APM_BIOS_DISENGAGED) == 0)
2411	    && (apm_info.connection_version > 0x0100)) {
2412		error = apm_engage_power_management(APM_DEVICE_ALL, 0);
2413		if (error)
2414			apm_error("disengage power management", error);
2415	}
2416	misc_deregister(&apm_device);
2417	remove_proc_entry("apm", NULL);
2418	if (power_off)
2419		pm_power_off = NULL;
2420	if (kapmd_task) {
2421		kthread_stop(kapmd_task);
2422		kapmd_task = NULL;
2423	}
2424}
2425
2426module_init(apm_init);
2427module_exit(apm_exit);
2428
2429MODULE_AUTHOR("Stephen Rothwell");
2430MODULE_DESCRIPTION("Advanced Power Management");
2431MODULE_LICENSE("GPL");
2432module_param(debug, bool, 0644);
2433MODULE_PARM_DESC(debug, "Enable debug mode");
2434module_param(power_off, bool, 0444);
2435MODULE_PARM_DESC(power_off, "Enable power off");
2436module_param(bounce_interval, int, 0444);
2437MODULE_PARM_DESC(bounce_interval,
2438		"Set the number of ticks to ignore suspend bounces");
2439module_param(allow_ints, bool, 0444);
2440MODULE_PARM_DESC(allow_ints, "Allow interrupts during BIOS calls");
2441module_param(broken_psr, bool, 0444);
2442MODULE_PARM_DESC(broken_psr, "BIOS has a broken GetPowerStatus call");
2443module_param(realmode_power_off, bool, 0444);
2444MODULE_PARM_DESC(realmode_power_off,
2445		"Switch to real mode before powering off");
2446module_param(idle_threshold, int, 0444);
2447MODULE_PARM_DESC(idle_threshold,
2448	"System idle percentage above which to make APM BIOS idle calls");
2449module_param(idle_period, int, 0444);
2450MODULE_PARM_DESC(idle_period,
2451	"Period (in sec/100) over which to caculate the idle percentage");
2452module_param(smp, bool, 0444);
2453MODULE_PARM_DESC(smp,
2454	"Set this to enable APM use on an SMP platform. Use with caution on older systems");
2455MODULE_ALIAS_MISCDEV(APM_MINOR_DEV);
v4.6
   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 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 compiler/assembler differences.
  70 *         Only try to turn off the first display device.
  71 *         Fix OOPS at power off with no APM BIOS by Jan Echternach
  72 *                   <echter@informatik.uni-rostock.de>
  73 *         Stephen Rothwell
  74 *    1.7: Modify driver's cached copy of the disabled/disengaged flags
  75 *         to reflect current state of APM BIOS.
  76 *         Chris Rankin <rankinc@bellsouth.net>
  77 *         Reset interrupt 0 timer to 100Hz after suspend
  78 *         Chad Miller <cmiller@surfsouth.com>
  79 *         Add CONFIG_APM_IGNORE_SUSPEND_BOUNCE
  80 *         Richard Gooch <rgooch@atnf.csiro.au>
  81 *         Allow boot time disabling of APM
  82 *         Make boot messages far less verbose by default
  83 *         Make asm safer
  84 *         Stephen Rothwell
  85 *    1.8: Add CONFIG_APM_RTC_IS_GMT
  86 *         Richard Gooch <rgooch@atnf.csiro.au>
  87 *         change APM_NOINTS to CONFIG_APM_ALLOW_INTS
  88 *         remove dependency on CONFIG_PROC_FS
  89 *         Stephen Rothwell
  90 *    1.9: Fix small typo.  <laslo@wodip.opole.pl>
  91 *         Try to cope with BIOS's that need to have all display
  92 *         devices blanked and not just the first one.
  93 *         Ross Paterson <ross@soi.city.ac.uk>
  94 *         Fix segment limit setting it has always been wrong as
  95 *         the segments needed to have byte granularity.
  96 *         Mark a few things __init.
  97 *         Add hack to allow power off of SMP systems by popular request.
  98 *         Use CONFIG_SMP instead of __SMP__
  99 *         Ignore BOUNCES for three seconds.
 100 *         Stephen Rothwell
 101 *   1.10: Fix for Thinkpad return code.
 102 *         Merge 2.2 and 2.3 drivers.
 103 *         Remove APM dependencies in arch/i386/kernel/process.c
 104 *         Remove APM dependencies in drivers/char/sysrq.c
 105 *         Reset time across standby.
 106 *         Allow more inititialisation on SMP.
 107 *         Remove CONFIG_APM_POWER_OFF and make it boot time
 108 *         configurable (default on).
 109 *         Make debug only a boot time parameter (remove APM_DEBUG).
 110 *         Try to blank all devices on any error.
 111 *   1.11: Remove APM dependencies in drivers/char/console.c
 112 *         Check nr_running to detect if we are idle (from
 113 *         Borislav Deianov <borislav@lix.polytechnique.fr>)
 114 *         Fix for bioses that don't zero the top part of the
 115 *         entrypoint offset (Mario Sitta <sitta@al.unipmn.it>)
 116 *         (reported by Panos Katsaloulis <teras@writeme.com>).
 117 *         Real mode power off patch (Walter Hofmann
 118 *         <Walter.Hofmann@physik.stud.uni-erlangen.de>).
 119 *   1.12: Remove CONFIG_SMP as the compiler will optimize
 120 *         the code away anyway (smp_num_cpus == 1 in UP)
 121 *         noted by Artur Skawina <skawina@geocities.com>.
 122 *         Make power off under SMP work again.
 123 *         Fix thinko with initial engaging of BIOS.
 124 *         Make sure power off only happens on CPU 0
 125 *         (Paul "Rusty" Russell <rusty@rustcorp.com.au>).
 126 *         Do error notification to user mode if BIOS calls fail.
 127 *         Move entrypoint offset fix to ...boot/setup.S
 128 *         where it belongs (Cosmos <gis88564@cis.nctu.edu.tw>).
 129 *         Remove smp-power-off. SMP users must now specify
 130 *         "apm=power-off" on the kernel command line. Suggested
 131 *         by Jim Avera <jima@hal.com>, modified by Alan Cox
 132 *         <alan@lxorguk.ukuu.org.uk>.
 133 *         Register the /proc/apm entry even on SMP so that
 134 *         scripts that check for it before doing power off
 135 *         work (Jim Avera <jima@hal.com>).
 136 *   1.13: Changes for new pm_ interfaces (Andy Henroid
 137 *         <andy_henroid@yahoo.com>).
 138 *         Modularize the code.
 139 *         Fix the Thinkpad (again) :-( (CONFIG_APM_IGNORE_MULTIPLE_SUSPENDS
 140 *         is now the way life works).
 141 *         Fix thinko in suspend() (wrong return).
 142 *         Notify drivers on critical suspend.
 143 *         Make kapmd absorb more idle time (Pavel Machek <pavel@ucw.cz>
 144 *         modified by sfr).
 145 *         Disable interrupts while we are suspended (Andy Henroid
 146 *         <andy_henroid@yahoo.com> fixed by sfr).
 147 *         Make power off work on SMP again (Tony Hoyle
 148 *         <tmh@magenta-logic.com> and <zlatko@iskon.hr>) modified by sfr.
 149 *         Remove CONFIG_APM_SUSPEND_BOUNCE.  The bounce ignore
 150 *         interval is now configurable.
 151 *   1.14: Make connection version persist across module unload/load.
 152 *         Enable and engage power management earlier.
 153 *         Disengage power management on module unload.
 154 *         Changed to use the sysrq-register hack for registering the
 155 *         power off function called by magic sysrq based upon discussions
 156 *         in irc://irc.openprojects.net/#kernelnewbies
 157 *         (Crutcher Dunnavant <crutcher+kernel@datastacks.com>).
 158 *         Make CONFIG_APM_REAL_MODE_POWER_OFF run time configurable.
 159 *         (Arjan van de Ven <arjanv@redhat.com>) modified by sfr.
 160 *         Work around byte swap bug in one of the Vaio's BIOS's
 161 *         (Marc Boucher <marc@mbsi.ca>).
 162 *         Exposed the disable flag to dmi so that we can handle known
 163 *         broken APM (Alan Cox <alan@lxorguk.ukuu.org.uk>).
 164 *   1.14ac: If the BIOS says "I slowed the CPU down" then don't spin
 165 *         calling it - instead idle. (Alan Cox <alan@lxorguk.ukuu.org.uk>)
 166 *         If an APM idle fails log it and idle sensibly
 167 *   1.15: Don't queue events to clients who open the device O_WRONLY.
 168 *         Don't expect replies from clients who open the device O_RDONLY.
 169 *         (Idea from Thomas Hood)
 170 *         Minor waitqueue cleanups. (John Fremlin <chief@bandits.org>)
 171 *   1.16: Fix idle calling. (Andreas Steinmetz <ast@domdv.de> et al.)
 172 *         Notify listeners of standby or suspend events before notifying
 173 *         drivers. Return EBUSY to ioctl() if suspend is rejected.
 174 *         (Russell King <rmk@arm.linux.org.uk> and Thomas Hood)
 175 *         Ignore first resume after we generate our own resume event
 176 *         after a suspend (Thomas Hood)
 177 *         Daemonize now gets rid of our controlling terminal (sfr).
 178 *         CONFIG_APM_CPU_IDLE now just affects the default value of
 179 *         idle_threshold (sfr).
 180 *         Change name of kernel apm daemon (as it no longer idles) (sfr).
 181 *   1.16ac: Fix up SMP support somewhat. You can now force SMP on and we
 182 *	   make _all_ APM calls on the CPU#0. Fix unsafe sign bug.
 183 *	   TODO: determine if its "boot CPU" or "CPU0" we want to lock to.
 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 from
 193 * http://www.microsoft.com/whdc/archive/amp_12.mspx  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/whdc/archive/amp_12.mspx]
 202 */
 203
 204#define pr_fmt(fmt) "apm: " fmt
 205
 206#include <linux/module.h>
 207
 208#include <linux/poll.h>
 209#include <linux/types.h>
 210#include <linux/stddef.h>
 211#include <linux/timer.h>
 212#include <linux/fcntl.h>
 213#include <linux/slab.h>
 214#include <linux/stat.h>
 215#include <linux/proc_fs.h>
 216#include <linux/seq_file.h>
 217#include <linux/miscdevice.h>
 218#include <linux/apm_bios.h>
 219#include <linux/init.h>
 220#include <linux/time.h>
 221#include <linux/sched.h>
 222#include <linux/pm.h>
 223#include <linux/capability.h>
 224#include <linux/device.h>
 225#include <linux/kernel.h>
 226#include <linux/freezer.h>
 227#include <linux/smp.h>
 228#include <linux/dmi.h>
 229#include <linux/suspend.h>
 230#include <linux/kthread.h>
 231#include <linux/jiffies.h>
 232#include <linux/acpi.h>
 233#include <linux/syscore_ops.h>
 234#include <linux/i8253.h>
 235#include <linux/cpuidle.h>
 236
 
 237#include <asm/uaccess.h>
 238#include <asm/desc.h>
 239#include <asm/olpc.h>
 240#include <asm/paravirt.h>
 241#include <asm/reboot.h>
 242
 243#if defined(CONFIG_APM_DISPLAY_BLANK) && defined(CONFIG_VT)
 244extern int (*console_blank_hook)(int);
 245#endif
 246
 247/*
 248 * The apm_bios device is one of the misc char devices.
 249 * This is its minor number.
 250 */
 251#define	APM_MINOR_DEV	134
 252
 253/*
 
 
 254 * Various options can be changed at boot time as follows:
 255 * (We allow underscores for compatibility with the modules code)
 256 *	apm=on/off			enable/disable APM
 257 *	    [no-]allow[-_]ints		allow interrupts during BIOS calls
 258 *	    [no-]broken[-_]psr		BIOS has a broken GetPowerStatus call
 259 *	    [no-]realmode[-_]power[-_]off	switch to real mode before
 260 *	    					powering off
 261 *	    [no-]debug			log some debugging messages
 262 *	    [no-]power[-_]off		power off on shutdown
 263 *	    [no-]smp			Use apm even on an SMP box
 264 *	    bounce[-_]interval=<n>	number of ticks to ignore suspend
 265 *	    				bounces
 266 *          idle[-_]threshold=<n>       System idle percentage above which to
 267 *                                      make APM BIOS idle calls. Set it to
 268 *                                      100 to disable.
 269 *          idle[-_]period=<n>          Period (in 1/100s of a second) over
 270 *                                      which the idle percentage is
 271 *                                      calculated.
 272 */
 273
 274/* KNOWN PROBLEM MACHINES:
 275 *
 276 * U: TI 4000M TravelMate: BIOS is *NOT* APM compliant
 277 *                         [Confirmed by TI representative]
 278 * ?: ACER 486DX4/75: uses dseg 0040, in violation of APM specification
 279 *                    [Confirmed by BIOS disassembly]
 280 *                    [This may work now ...]
 281 * P: Toshiba 1950S: battery life information only gets updated after resume
 282 * P: Midwest Micro Soundbook Elite DX2/66 monochrome: screen blanking
 283 * 	broken in BIOS [Reported by Garst R. Reese <reese@isn.net>]
 284 * ?: AcerNote-950: oops on reading /proc/apm - workaround is a WIP
 285 * 	Neale Banks <neale@lowendale.com.au> December 2000
 286 *
 287 * Legend: U = unusable with APM patches
 288 *         P = partially usable with APM patches
 289 */
 290
 291/*
 292 * Define as 1 to make the driver always call the APM BIOS busy
 293 * routine even if the clock was not reported as slowed by the
 294 * idle routine.  Otherwise, define as 0.
 295 */
 296#define ALWAYS_CALL_BUSY   1
 297
 298/*
 299 * Define to make the APM BIOS calls zero all data segment registers (so
 300 * that an incorrect BIOS implementation will cause a kernel panic if it
 301 * tries to write to arbitrary memory).
 302 */
 303#define APM_ZERO_SEGS
 304
 305#include <asm/apm.h>
 306
 307/*
 308 * Define to re-initialize the interrupt 0 timer to 100 Hz after a suspend.
 309 * This patched by Chad Miller <cmiller@surfsouth.com>, original code by
 310 * David Chen <chen@ctpa04.mit.edu>
 311 */
 312#undef INIT_TIMER_AFTER_SUSPEND
 313
 314#ifdef INIT_TIMER_AFTER_SUSPEND
 315#include <linux/timex.h>
 316#include <asm/io.h>
 317#include <linux/delay.h>
 318#endif
 319
 320/*
 321 * Need to poll the APM BIOS every second
 322 */
 323#define APM_CHECK_TIMEOUT	(HZ)
 324
 325/*
 326 * Ignore suspend events for this amount of time after a resume
 327 */
 328#define DEFAULT_BOUNCE_INTERVAL	(3 * HZ)
 329
 330/*
 331 * Maximum number of events stored
 332 */
 333#define APM_MAX_EVENTS		20
 334
 335/*
 336 * The per-file APM data
 337 */
 338struct apm_user {
 339	int		magic;
 340	struct apm_user *next;
 341	unsigned int	suser: 1;
 342	unsigned int	writer: 1;
 343	unsigned int	reader: 1;
 344	unsigned int	suspend_wait: 1;
 345	int		suspend_result;
 346	int		suspends_pending;
 347	int		standbys_pending;
 348	int		suspends_read;
 349	int		standbys_read;
 350	int		event_head;
 351	int		event_tail;
 352	apm_event_t	events[APM_MAX_EVENTS];
 353};
 354
 355/*
 356 * The magic number in apm_user
 357 */
 358#define APM_BIOS_MAGIC		0x4101
 359
 360/*
 361 * idle percentage above which bios idle calls are done
 362 */
 363#ifdef CONFIG_APM_CPU_IDLE
 
 364#define DEFAULT_IDLE_THRESHOLD	95
 365#else
 366#define DEFAULT_IDLE_THRESHOLD	100
 367#endif
 368#define DEFAULT_IDLE_PERIOD	(100 / 3)
 369
 370static int apm_cpu_idle(struct cpuidle_device *dev,
 371			struct cpuidle_driver *drv, int index);
 372
 373static struct cpuidle_driver apm_idle_driver = {
 374	.name = "apm_idle",
 375	.owner = THIS_MODULE,
 376	.states = {
 377		{ /* entry 0 is for polling */ },
 378		{ /* entry 1 is for APM idle */
 379			.name = "APM",
 380			.desc = "APM idle",
 381			.exit_latency = 250,	/* WAG */
 382			.target_residency = 500,	/* WAG */
 383			.enter = &apm_cpu_idle
 384		},
 385	},
 386	.state_count = 2,
 387};
 388
 389static struct cpuidle_device apm_cpuidle_device;
 390
 391/*
 392 * Local variables
 393 */
 394__visible struct {
 395	unsigned long	offset;
 396	unsigned short	segment;
 397} apm_bios_entry;
 398static int clock_slowed;
 399static int idle_threshold __read_mostly = DEFAULT_IDLE_THRESHOLD;
 400static int idle_period __read_mostly = DEFAULT_IDLE_PERIOD;
 
 401static int suspends_pending;
 402static int standbys_pending;
 403static int ignore_sys_suspend;
 404static int ignore_normal_resume;
 405static int bounce_interval __read_mostly = DEFAULT_BOUNCE_INTERVAL;
 406
 407static bool debug __read_mostly;
 408static bool smp __read_mostly;
 409static int apm_disabled = -1;
 410#ifdef CONFIG_SMP
 411static bool power_off;
 412#else
 413static bool power_off = 1;
 414#endif
 415static bool realmode_power_off;
 416#ifdef CONFIG_APM_ALLOW_INTS
 417static bool allow_ints = 1;
 418#else
 419static bool allow_ints;
 420#endif
 421static bool broken_psr;
 422
 423static DECLARE_WAIT_QUEUE_HEAD(apm_waitqueue);
 424static DECLARE_WAIT_QUEUE_HEAD(apm_suspend_waitqueue);
 425static struct apm_user *user_list;
 426static DEFINE_SPINLOCK(user_list_lock);
 427static DEFINE_MUTEX(apm_mutex);
 428
 429/*
 430 * Set up a segment that references the real mode segment 0x40
 431 * that extends up to the end of page zero (that we have reserved).
 432 * This is for buggy BIOS's that refer to (real mode) segment 0x40
 433 * even though they are called in protected mode.
 434 */
 435static struct desc_struct bad_bios_desc = GDT_ENTRY_INIT(0x4092,
 436			(unsigned long)__va(0x400UL), PAGE_SIZE - 0x400 - 1);
 437
 438static const char driver_version[] = "1.16ac";	/* no spaces */
 439
 440static struct task_struct *kapmd_task;
 441
 442/*
 443 *	APM event names taken from the APM 1.2 specification. These are
 444 *	the message codes that the BIOS uses to tell us about events
 445 */
 446static const char * const apm_event_name[] = {
 447	"system standby",
 448	"system suspend",
 449	"normal resume",
 450	"critical resume",
 451	"low battery",
 452	"power status change",
 453	"update time",
 454	"critical suspend",
 455	"user standby",
 456	"user suspend",
 457	"system standby resume",
 458	"capabilities change"
 459};
 460#define NR_APM_EVENT_NAME ARRAY_SIZE(apm_event_name)
 461
 462typedef struct lookup_t {
 463	int	key;
 464	char 	*msg;
 465} lookup_t;
 466
 467/*
 468 *	The BIOS returns a set of standard error codes in AX when the
 469 *	carry flag is set.
 470 */
 471
 472static const lookup_t error_table[] = {
 473/* N/A	{ APM_SUCCESS,		"Operation succeeded" }, */
 474	{ APM_DISABLED,		"Power management disabled" },
 475	{ APM_CONNECTED,	"Real mode interface already connected" },
 476	{ APM_NOT_CONNECTED,	"Interface not connected" },
 477	{ APM_16_CONNECTED,	"16 bit interface already connected" },
 478/* N/A	{ APM_16_UNSUPPORTED,	"16 bit interface not supported" }, */
 479	{ APM_32_CONNECTED,	"32 bit interface already connected" },
 480	{ APM_32_UNSUPPORTED,	"32 bit interface not supported" },
 481	{ APM_BAD_DEVICE,	"Unrecognized device ID" },
 482	{ APM_BAD_PARAM,	"Parameter out of range" },
 483	{ APM_NOT_ENGAGED,	"Interface not engaged" },
 484	{ APM_BAD_FUNCTION,     "Function not supported" },
 485	{ APM_RESUME_DISABLED,	"Resume timer disabled" },
 486	{ APM_BAD_STATE,	"Unable to enter requested state" },
 487/* N/A	{ APM_NO_EVENTS,	"No events pending" }, */
 488	{ APM_NO_ERROR,		"BIOS did not set a return code" },
 489	{ APM_NOT_PRESENT,	"No APM present" }
 490};
 491#define ERROR_COUNT	ARRAY_SIZE(error_table)
 492
 493/**
 494 *	apm_error	-	display an APM error
 495 *	@str: information string
 496 *	@err: APM BIOS return code
 497 *
 498 *	Write a meaningful log entry to the kernel log in the event of
 499 *	an APM error.  Note that this also handles (negative) kernel errors.
 500 */
 501
 502static void apm_error(char *str, int err)
 503{
 504	int i;
 505
 506	for (i = 0; i < ERROR_COUNT; i++)
 507		if (error_table[i].key == err)
 508			break;
 509	if (i < ERROR_COUNT)
 510		pr_notice("%s: %s\n", str, error_table[i].msg);
 511	else if (err < 0)
 512		pr_notice("%s: linux error code %i\n", str, err);
 513	else
 514		pr_notice("%s: unknown error code %#2.2x\n",
 515		       str, err);
 516}
 517
 518/*
 519 * These are the actual BIOS calls.  Depending on APM_ZERO_SEGS and
 520 * apm_info.allow_ints, we are being really paranoid here!  Not only
 521 * are interrupts disabled, but all the segment registers (except SS)
 522 * are saved and zeroed this means that if the BIOS tries to reference
 523 * any data without explicitly loading the segment registers, the kernel
 524 * will fault immediately rather than have some unforeseen circumstances
 525 * for the rest of the kernel.  And it will be very obvious!  :-) Doing
 526 * this depends on CS referring to the same physical memory as DS so that
 527 * DS can be zeroed before the call. Unfortunately, we can't do anything
 528 * about the stack segment/pointer.  Also, we tell the compiler that
 529 * everything could change.
 530 *
 531 * Also, we KNOW that for the non error case of apm_bios_call, there
 532 * is no useful data returned in the low order 8 bits of eax.
 533 */
 534
 535static inline unsigned long __apm_irq_save(void)
 536{
 537	unsigned long flags;
 538	local_save_flags(flags);
 539	if (apm_info.allow_ints) {
 540		if (irqs_disabled_flags(flags))
 541			local_irq_enable();
 542	} else
 543		local_irq_disable();
 544
 545	return flags;
 546}
 547
 548#define apm_irq_save(flags) \
 549	do { flags = __apm_irq_save(); } while (0)
 550
 551static inline void apm_irq_restore(unsigned long flags)
 552{
 553	if (irqs_disabled_flags(flags))
 554		local_irq_disable();
 555	else if (irqs_disabled())
 556		local_irq_enable();
 557}
 558
 559#ifdef APM_ZERO_SEGS
 560#	define APM_DECL_SEGS \
 561		unsigned int saved_fs; unsigned int saved_gs;
 562#	define APM_DO_SAVE_SEGS \
 563		savesegment(fs, saved_fs); savesegment(gs, saved_gs)
 564#	define APM_DO_RESTORE_SEGS \
 565		loadsegment(fs, saved_fs); loadsegment(gs, saved_gs)
 566#else
 567#	define APM_DECL_SEGS
 568#	define APM_DO_SAVE_SEGS
 569#	define APM_DO_RESTORE_SEGS
 570#endif
 571
 572struct apm_bios_call {
 573	u32 func;
 574	/* In and out */
 575	u32 ebx;
 576	u32 ecx;
 577	/* Out only */
 578	u32 eax;
 579	u32 edx;
 580	u32 esi;
 581
 582	/* Error: -ENOMEM, or bits 8-15 of eax */
 583	int err;
 584};
 585
 586/**
 587 *	__apm_bios_call - Make an APM BIOS 32bit call
 588 *	@_call: pointer to struct apm_bios_call.
 589 *
 590 *	Make an APM call using the 32bit protected mode interface. The
 591 *	caller is responsible for knowing if APM BIOS is configured and
 592 *	enabled. This call can disable interrupts for a long period of
 593 *	time on some laptops.  The return value is in AH and the carry
 594 *	flag is loaded into AL.  If there is an error, then the error
 595 *	code is returned in AH (bits 8-15 of eax) and this function
 596 *	returns non-zero.
 597 *
 598 *	Note: this makes the call on the current CPU.
 599 */
 600static long __apm_bios_call(void *_call)
 601{
 602	APM_DECL_SEGS
 603	unsigned long		flags;
 604	int			cpu;
 605	struct desc_struct	save_desc_40;
 606	struct desc_struct	*gdt;
 607	struct apm_bios_call	*call = _call;
 608
 609	cpu = get_cpu();
 610	BUG_ON(cpu != 0);
 611	gdt = get_cpu_gdt_table(cpu);
 612	save_desc_40 = gdt[0x40 / 8];
 613	gdt[0x40 / 8] = bad_bios_desc;
 614
 615	apm_irq_save(flags);
 616	APM_DO_SAVE_SEGS;
 617	apm_bios_call_asm(call->func, call->ebx, call->ecx,
 618			  &call->eax, &call->ebx, &call->ecx, &call->edx,
 619			  &call->esi);
 620	APM_DO_RESTORE_SEGS;
 621	apm_irq_restore(flags);
 622	gdt[0x40 / 8] = save_desc_40;
 623	put_cpu();
 624
 625	return call->eax & 0xff;
 626}
 627
 628/* Run __apm_bios_call or __apm_bios_call_simple on CPU 0 */
 629static int on_cpu0(long (*fn)(void *), struct apm_bios_call *call)
 630{
 631	int ret;
 632
 633	/* Don't bother with work_on_cpu in the common case, so we don't
 634	 * have to worry about OOM or overhead. */
 635	if (get_cpu() == 0) {
 636		ret = fn(call);
 637		put_cpu();
 638	} else {
 639		put_cpu();
 640		ret = work_on_cpu(0, fn, call);
 641	}
 642
 643	/* work_on_cpu can fail with -ENOMEM */
 644	if (ret < 0)
 645		call->err = ret;
 646	else
 647		call->err = (call->eax >> 8) & 0xff;
 648
 649	return ret;
 650}
 651
 652/**
 653 *	apm_bios_call	-	Make an APM BIOS 32bit call (on CPU 0)
 654 *	@call: the apm_bios_call registers.
 655 *
 656 *	If there is an error, it is returned in @call.err.
 657 */
 658static int apm_bios_call(struct apm_bios_call *call)
 659{
 660	return on_cpu0(__apm_bios_call, call);
 661}
 662
 663/**
 664 *	__apm_bios_call_simple - Make an APM BIOS 32bit call (on CPU 0)
 665 *	@_call: pointer to struct apm_bios_call.
 666 *
 667 *	Make a BIOS call that returns one value only, or just status.
 668 *	If there is an error, then the error code is returned in AH
 669 *	(bits 8-15 of eax) and this function returns non-zero (it can
 670 *	also return -ENOMEM). This is used for simpler BIOS operations.
 671 *	This call may hold interrupts off for a long time on some laptops.
 672 *
 673 *	Note: this makes the call on the current CPU.
 674 */
 675static long __apm_bios_call_simple(void *_call)
 676{
 677	u8			error;
 678	APM_DECL_SEGS
 679	unsigned long		flags;
 680	int			cpu;
 681	struct desc_struct	save_desc_40;
 682	struct desc_struct	*gdt;
 683	struct apm_bios_call	*call = _call;
 684
 685	cpu = get_cpu();
 686	BUG_ON(cpu != 0);
 687	gdt = get_cpu_gdt_table(cpu);
 688	save_desc_40 = gdt[0x40 / 8];
 689	gdt[0x40 / 8] = bad_bios_desc;
 690
 691	apm_irq_save(flags);
 692	APM_DO_SAVE_SEGS;
 693	error = apm_bios_call_simple_asm(call->func, call->ebx, call->ecx,
 694					 &call->eax);
 695	APM_DO_RESTORE_SEGS;
 696	apm_irq_restore(flags);
 697	gdt[0x40 / 8] = save_desc_40;
 698	put_cpu();
 699	return error;
 700}
 701
 702/**
 703 *	apm_bios_call_simple	-	make a simple APM BIOS 32bit call
 704 *	@func: APM function to invoke
 705 *	@ebx_in: EBX register value for BIOS call
 706 *	@ecx_in: ECX register value for BIOS call
 707 *	@eax: EAX register on return from the BIOS call
 708 *	@err: bits
 709 *
 710 *	Make a BIOS call that returns one value only, or just status.
 711 *	If there is an error, then the error code is returned in @err
 712 *	and this function returns non-zero. This is used for simpler
 713 *	BIOS operations.  This call may hold interrupts off for a long
 714 *	time on some laptops.
 715 */
 716static int apm_bios_call_simple(u32 func, u32 ebx_in, u32 ecx_in, u32 *eax,
 717				int *err)
 718{
 719	struct apm_bios_call call;
 720	int ret;
 721
 722	call.func = func;
 723	call.ebx = ebx_in;
 724	call.ecx = ecx_in;
 725
 726	ret = on_cpu0(__apm_bios_call_simple, &call);
 727	*eax = call.eax;
 728	*err = call.err;
 729	return ret;
 730}
 731
 732/**
 733 *	apm_driver_version	-	APM driver version
 734 *	@val:	loaded with the APM version on return
 735 *
 736 *	Retrieve the APM version supported by the BIOS. This is only
 737 *	supported for APM 1.1 or higher. An error indicates APM 1.0 is
 738 *	probably present.
 739 *
 740 *	On entry val should point to a value indicating the APM driver
 741 *	version with the high byte being the major and the low byte the
 742 *	minor number both in BCD
 743 *
 744 *	On return it will hold the BIOS revision supported in the
 745 *	same format.
 746 */
 747
 748static int apm_driver_version(u_short *val)
 749{
 750	u32 eax;
 751	int err;
 752
 753	if (apm_bios_call_simple(APM_FUNC_VERSION, 0, *val, &eax, &err))
 754		return err;
 755	*val = eax;
 756	return APM_SUCCESS;
 757}
 758
 759/**
 760 *	apm_get_event	-	get an APM event from the BIOS
 761 *	@event: pointer to the event
 762 *	@info: point to the event information
 763 *
 764 *	The APM BIOS provides a polled information for event
 765 *	reporting. The BIOS expects to be polled at least every second
 766 *	when events are pending. When a message is found the caller should
 767 *	poll until no more messages are present.  However, this causes
 768 *	problems on some laptops where a suspend event notification is
 769 *	not cleared until it is acknowledged.
 770 *
 771 *	Additional information is returned in the info pointer, providing
 772 *	that APM 1.2 is in use. If no messges are pending the value 0x80
 773 *	is returned (No power management events pending).
 774 */
 775static int apm_get_event(apm_event_t *event, apm_eventinfo_t *info)
 776{
 777	struct apm_bios_call call;
 778
 779	call.func = APM_FUNC_GET_EVENT;
 780	call.ebx = call.ecx = 0;
 781
 782	if (apm_bios_call(&call))
 783		return call.err;
 784
 785	*event = call.ebx;
 786	if (apm_info.connection_version < 0x0102)
 787		*info = ~0; /* indicate info not valid */
 788	else
 789		*info = call.ecx;
 790	return APM_SUCCESS;
 791}
 792
 793/**
 794 *	set_power_state	-	set the power management state
 795 *	@what: which items to transition
 796 *	@state: state to transition to
 797 *
 798 *	Request an APM change of state for one or more system devices. The
 799 *	processor state must be transitioned last of all. what holds the
 800 *	class of device in the upper byte and the device number (0xFF for
 801 *	all) for the object to be transitioned.
 802 *
 803 *	The state holds the state to transition to, which may in fact
 804 *	be an acceptance of a BIOS requested state change.
 805 */
 806
 807static int set_power_state(u_short what, u_short state)
 808{
 809	u32 eax;
 810	int err;
 811
 812	if (apm_bios_call_simple(APM_FUNC_SET_STATE, what, state, &eax, &err))
 813		return err;
 814	return APM_SUCCESS;
 815}
 816
 817/**
 818 *	set_system_power_state - set system wide power state
 819 *	@state: which state to enter
 820 *
 821 *	Transition the entire system into a new APM power state.
 822 */
 823
 824static int set_system_power_state(u_short state)
 825{
 826	return set_power_state(APM_DEVICE_ALL, state);
 827}
 828
 829/**
 830 *	apm_do_idle	-	perform power saving
 831 *
 832 *	This function notifies the BIOS that the processor is (in the view
 833 *	of the OS) idle. It returns -1 in the event that the BIOS refuses
 834 *	to handle the idle request. On a success the function returns 1
 835 *	if the BIOS did clock slowing or 0 otherwise.
 836 */
 837
 838static int apm_do_idle(void)
 839{
 840	u32 eax;
 841	u8 ret = 0;
 842	int idled = 0;
 
 843	int err = 0;
 844
 
 
 
 
 
 
 
 
 
 845	if (!need_resched()) {
 846		idled = 1;
 847		ret = apm_bios_call_simple(APM_FUNC_IDLE, 0, 0, &eax, &err);
 848	}
 
 
 849
 850	if (!idled)
 851		return 0;
 852
 853	if (ret) {
 854		static unsigned long t;
 855
 856		/* This always fails on some SMP boards running UP kernels.
 857		 * Only report the failure the first 5 times.
 858		 */
 859		if (++t < 5) {
 860			printk(KERN_DEBUG "apm_do_idle failed (%d)\n", err);
 861			t = jiffies;
 862		}
 863		return -1;
 864	}
 865	clock_slowed = (apm_info.bios.flags & APM_IDLE_SLOWS_CLOCK) != 0;
 866	return clock_slowed;
 867}
 868
 869/**
 870 *	apm_do_busy	-	inform the BIOS the CPU is busy
 871 *
 872 *	Request that the BIOS brings the CPU back to full performance.
 873 */
 874
 875static void apm_do_busy(void)
 876{
 877	u32 dummy;
 878	int err;
 879
 880	if (clock_slowed || ALWAYS_CALL_BUSY) {
 881		(void)apm_bios_call_simple(APM_FUNC_BUSY, 0, 0, &dummy, &err);
 882		clock_slowed = 0;
 883	}
 884}
 885
 886/*
 887 * If no process has really been interested in
 888 * the CPU for some time, we want to call BIOS
 889 * power management - we probably want
 890 * to conserve power.
 891 */
 892#define IDLE_CALC_LIMIT	(HZ * 100)
 893#define IDLE_LEAKY_MAX	16
 894
 
 
 895/**
 896 * apm_cpu_idle		-	cpu idling for APM capable Linux
 897 *
 898 * This is the idling function the kernel executes when APM is available. It
 899 * tries to do BIOS powermanagement based on the average system idle time.
 900 * Furthermore it calls the system default idle routine.
 901 */
 902
 903static int apm_cpu_idle(struct cpuidle_device *dev,
 904	struct cpuidle_driver *drv, int index)
 905{
 906	static int use_apm_idle; /* = 0 */
 907	static unsigned int last_jiffies; /* = 0 */
 908	static unsigned int last_stime; /* = 0 */
 909	cputime_t stime;
 910
 911	int apm_idle_done = 0;
 912	unsigned int jiffies_since_last_check = jiffies - last_jiffies;
 913	unsigned int bucket;
 914
 
 915recalc:
 916	task_cputime(current, NULL, &stime);
 917	if (jiffies_since_last_check > IDLE_CALC_LIMIT) {
 918		use_apm_idle = 0;
 
 
 919	} else if (jiffies_since_last_check > idle_period) {
 920		unsigned int idle_percentage;
 921
 922		idle_percentage = cputime_to_jiffies(stime - last_stime);
 923		idle_percentage *= 100;
 924		idle_percentage /= jiffies_since_last_check;
 925		use_apm_idle = (idle_percentage > idle_threshold);
 926		if (apm_info.forbid_idle)
 927			use_apm_idle = 0;
 
 
 928	}
 929
 930	last_jiffies = jiffies;
 931	last_stime = stime;
 932
 933	bucket = IDLE_LEAKY_MAX;
 934
 935	while (!need_resched()) {
 936		if (use_apm_idle) {
 937			unsigned int t;
 938
 939			t = jiffies;
 940			switch (apm_do_idle()) {
 941			case 0:
 942				apm_idle_done = 1;
 943				if (t != jiffies) {
 944					if (bucket) {
 945						bucket = IDLE_LEAKY_MAX;
 946						continue;
 947					}
 948				} else if (bucket) {
 949					bucket--;
 950					continue;
 951				}
 952				break;
 953			case 1:
 954				apm_idle_done = 1;
 955				break;
 956			default: /* BIOS refused */
 957				break;
 958			}
 959		}
 960		default_idle();
 
 
 
 961		local_irq_disable();
 962		jiffies_since_last_check = jiffies - last_jiffies;
 963		if (jiffies_since_last_check > idle_period)
 964			goto recalc;
 965	}
 966
 967	if (apm_idle_done)
 968		apm_do_busy();
 969
 970	return index;
 971}
 972
 973/**
 974 *	apm_power_off	-	ask the BIOS to power off
 975 *
 976 *	Handle the power off sequence. This is the one piece of code we
 977 *	will execute even on SMP machines. In order to deal with BIOS
 978 *	bugs we support real mode APM BIOS power off calls. We also make
 979 *	the SMP call on CPU0 as some systems will only honour this call
 980 *	on their first cpu.
 981 */
 982
 983static void apm_power_off(void)
 984{
 985	/* Some bioses don't like being called from CPU != 0 */
 986	if (apm_info.realmode_power_off) {
 987		set_cpus_allowed_ptr(current, cpumask_of(0));
 988		machine_real_restart(MRR_APM);
 989	} else {
 990		(void)set_system_power_state(APM_STATE_OFF);
 991	}
 992}
 993
 994#ifdef CONFIG_APM_DO_ENABLE
 995
 996/**
 997 *	apm_enable_power_management - enable BIOS APM power management
 998 *	@enable: enable yes/no
 999 *
1000 *	Enable or disable the APM BIOS power services.
1001 */
1002
1003static int apm_enable_power_management(int enable)
1004{
1005	u32 eax;
1006	int err;
1007
1008	if ((enable == 0) && (apm_info.bios.flags & APM_BIOS_DISENGAGED))
1009		return APM_NOT_ENGAGED;
1010	if (apm_bios_call_simple(APM_FUNC_ENABLE_PM, APM_DEVICE_BALL,
1011				 enable, &eax, &err))
1012		return err;
1013	if (enable)
1014		apm_info.bios.flags &= ~APM_BIOS_DISABLED;
1015	else
1016		apm_info.bios.flags |= APM_BIOS_DISABLED;
1017	return APM_SUCCESS;
1018}
1019#endif
1020
1021/**
1022 *	apm_get_power_status	-	get current power state
1023 *	@status: returned status
1024 *	@bat: battery info
1025 *	@life: estimated life
1026 *
1027 *	Obtain the current power status from the APM BIOS. We return a
1028 *	status which gives the rough battery status, and current power
1029 *	source. The bat value returned give an estimate as a percentage
1030 *	of life and a status value for the battery. The estimated life
1031 *	if reported is a lifetime in secodnds/minutes at current powwer
1032 *	consumption.
1033 */
1034
1035static int apm_get_power_status(u_short *status, u_short *bat, u_short *life)
1036{
1037	struct apm_bios_call call;
1038
1039	call.func = APM_FUNC_GET_STATUS;
1040	call.ebx = APM_DEVICE_ALL;
1041	call.ecx = 0;
1042
1043	if (apm_info.get_power_status_broken)
1044		return APM_32_UNSUPPORTED;
1045	if (apm_bios_call(&call))
1046		return call.err;
1047	*status = call.ebx;
1048	*bat = call.ecx;
1049	if (apm_info.get_power_status_swabinminutes) {
1050		*life = swab16((u16)call.edx);
1051		*life |= 0x8000;
1052	} else
1053		*life = call.edx;
1054	return APM_SUCCESS;
1055}
1056
1057#if 0
1058static int apm_get_battery_status(u_short which, u_short *status,
1059				  u_short *bat, u_short *life, u_short *nbat)
1060{
1061	u32 eax;
1062	u32 ebx;
1063	u32 ecx;
1064	u32 edx;
1065	u32 esi;
1066
1067	if (apm_info.connection_version < 0x0102) {
1068		/* pretend we only have one battery. */
1069		if (which != 1)
1070			return APM_BAD_DEVICE;
1071		*nbat = 1;
1072		return apm_get_power_status(status, bat, life);
1073	}
1074
1075	if (apm_bios_call(APM_FUNC_GET_STATUS, (0x8000 | (which)), 0, &eax,
1076			  &ebx, &ecx, &edx, &esi))
1077		return (eax >> 8) & 0xff;
1078	*status = ebx;
1079	*bat = ecx;
1080	*life = edx;
1081	*nbat = esi;
1082	return APM_SUCCESS;
1083}
1084#endif
1085
1086/**
1087 *	apm_engage_power_management	-	enable PM on a device
1088 *	@device: identity of device
1089 *	@enable: on/off
1090 *
1091 *	Activate or deactivate power management on either a specific device
1092 *	or the entire system (%APM_DEVICE_ALL).
1093 */
1094
1095static int apm_engage_power_management(u_short device, int enable)
1096{
1097	u32 eax;
1098	int err;
1099
1100	if ((enable == 0) && (device == APM_DEVICE_ALL)
1101	    && (apm_info.bios.flags & APM_BIOS_DISABLED))
1102		return APM_DISABLED;
1103	if (apm_bios_call_simple(APM_FUNC_ENGAGE_PM, device, enable,
1104				 &eax, &err))
1105		return err;
1106	if (device == APM_DEVICE_ALL) {
1107		if (enable)
1108			apm_info.bios.flags &= ~APM_BIOS_DISENGAGED;
1109		else
1110			apm_info.bios.flags |= APM_BIOS_DISENGAGED;
1111	}
1112	return APM_SUCCESS;
1113}
1114
1115#if defined(CONFIG_APM_DISPLAY_BLANK) && defined(CONFIG_VT)
1116
1117/**
1118 *	apm_console_blank	-	blank the display
1119 *	@blank: on/off
1120 *
1121 *	Attempt to blank the console, firstly by blanking just video device
1122 *	zero, and if that fails (some BIOSes don't support it) then it blanks
1123 *	all video devices. Typically the BIOS will do laptop backlight and
1124 *	monitor powerdown for us.
1125 */
1126
1127static int apm_console_blank(int blank)
1128{
1129	int error = APM_NOT_ENGAGED; /* silence gcc */
1130	int i;
1131	u_short state;
1132	static const u_short dev[3] = { 0x100, 0x1FF, 0x101 };
1133
1134	state = blank ? APM_STATE_STANDBY : APM_STATE_READY;
1135
1136	for (i = 0; i < ARRAY_SIZE(dev); i++) {
1137		error = set_power_state(dev[i], state);
1138
1139		if ((error == APM_SUCCESS) || (error == APM_NO_ERROR))
1140			return 1;
1141
1142		if (error == APM_NOT_ENGAGED)
1143			break;
1144	}
1145
1146	if (error == APM_NOT_ENGAGED) {
1147		static int tried;
1148		int eng_error;
1149		if (tried++ == 0) {
1150			eng_error = apm_engage_power_management(APM_DEVICE_ALL, 1);
1151			if (eng_error) {
1152				apm_error("set display", error);
1153				apm_error("engage interface", eng_error);
1154				return 0;
1155			} else
1156				return apm_console_blank(blank);
1157		}
1158	}
1159	apm_error("set display", error);
1160	return 0;
1161}
1162#endif
1163
1164static int queue_empty(struct apm_user *as)
1165{
1166	return as->event_head == as->event_tail;
1167}
1168
1169static apm_event_t get_queued_event(struct apm_user *as)
1170{
1171	if (++as->event_tail >= APM_MAX_EVENTS)
1172		as->event_tail = 0;
1173	return as->events[as->event_tail];
1174}
1175
1176static void queue_event(apm_event_t event, struct apm_user *sender)
1177{
1178	struct apm_user *as;
1179
1180	spin_lock(&user_list_lock);
1181	if (user_list == NULL)
1182		goto out;
1183	for (as = user_list; as != NULL; as = as->next) {
1184		if ((as == sender) || (!as->reader))
1185			continue;
1186		if (++as->event_head >= APM_MAX_EVENTS)
1187			as->event_head = 0;
1188
1189		if (as->event_head == as->event_tail) {
1190			static int notified;
1191
1192			if (notified++ == 0)
1193				pr_err("an event queue overflowed\n");
1194			if (++as->event_tail >= APM_MAX_EVENTS)
1195				as->event_tail = 0;
1196		}
1197		as->events[as->event_head] = event;
1198		if (!as->suser || !as->writer)
1199			continue;
1200		switch (event) {
1201		case APM_SYS_SUSPEND:
1202		case APM_USER_SUSPEND:
1203			as->suspends_pending++;
1204			suspends_pending++;
1205			break;
1206
1207		case APM_SYS_STANDBY:
1208		case APM_USER_STANDBY:
1209			as->standbys_pending++;
1210			standbys_pending++;
1211			break;
1212		}
1213	}
1214	wake_up_interruptible(&apm_waitqueue);
1215out:
1216	spin_unlock(&user_list_lock);
1217}
1218
1219static void reinit_timer(void)
1220{
1221#ifdef INIT_TIMER_AFTER_SUSPEND
1222	unsigned long flags;
1223
1224	raw_spin_lock_irqsave(&i8253_lock, flags);
1225	/* set the clock to HZ */
1226	outb_p(0x34, PIT_MODE);		/* binary, mode 2, LSB/MSB, ch 0 */
1227	udelay(10);
1228	outb_p(LATCH & 0xff, PIT_CH0);	/* LSB */
1229	udelay(10);
1230	outb_p(LATCH >> 8, PIT_CH0);	/* MSB */
1231	udelay(10);
1232	raw_spin_unlock_irqrestore(&i8253_lock, flags);
1233#endif
1234}
1235
1236static int suspend(int vetoable)
1237{
1238	int err;
1239	struct apm_user	*as;
1240
1241	dpm_suspend_start(PMSG_SUSPEND);
1242	dpm_suspend_end(PMSG_SUSPEND);
 
1243
1244	local_irq_disable();
1245	syscore_suspend();
1246
1247	local_irq_enable();
1248
1249	save_processor_state();
1250	err = set_system_power_state(APM_STATE_SUSPEND);
1251	ignore_normal_resume = 1;
1252	restore_processor_state();
1253
1254	local_irq_disable();
1255	reinit_timer();
1256
1257	if (err == APM_NO_ERROR)
1258		err = APM_SUCCESS;
1259	if (err != APM_SUCCESS)
1260		apm_error("suspend", err);
1261	err = (err == APM_SUCCESS) ? 0 : -EIO;
1262
1263	syscore_resume();
1264	local_irq_enable();
1265
1266	dpm_resume_start(PMSG_RESUME);
 
1267	dpm_resume_end(PMSG_RESUME);
1268
1269	queue_event(APM_NORMAL_RESUME, NULL);
1270	spin_lock(&user_list_lock);
1271	for (as = user_list; as != NULL; as = as->next) {
1272		as->suspend_wait = 0;
1273		as->suspend_result = err;
1274	}
1275	spin_unlock(&user_list_lock);
1276	wake_up_interruptible(&apm_suspend_waitqueue);
1277	return err;
1278}
1279
1280static void standby(void)
1281{
1282	int err;
1283
1284	dpm_suspend_end(PMSG_SUSPEND);
1285
1286	local_irq_disable();
1287	syscore_suspend();
1288	local_irq_enable();
1289
1290	err = set_system_power_state(APM_STATE_STANDBY);
1291	if ((err != APM_SUCCESS) && (err != APM_NO_ERROR))
1292		apm_error("standby", err);
1293
1294	local_irq_disable();
1295	syscore_resume();
1296	local_irq_enable();
1297
1298	dpm_resume_start(PMSG_RESUME);
1299}
1300
1301static apm_event_t get_event(void)
1302{
1303	int error;
1304	apm_event_t event = APM_NO_EVENTS; /* silence gcc */
1305	apm_eventinfo_t	info;
1306
1307	static int notified;
1308
1309	/* we don't use the eventinfo */
1310	error = apm_get_event(&event, &info);
1311	if (error == APM_SUCCESS)
1312		return event;
1313
1314	if ((error != APM_NO_EVENTS) && (notified++ == 0))
1315		apm_error("get_event", error);
1316
1317	return 0;
1318}
1319
1320static void check_events(void)
1321{
1322	apm_event_t event;
1323	static unsigned long last_resume;
1324	static int ignore_bounce;
1325
1326	while ((event = get_event()) != 0) {
1327		if (debug) {
1328			if (event <= NR_APM_EVENT_NAME)
1329				printk(KERN_DEBUG "apm: received %s notify\n",
1330				       apm_event_name[event - 1]);
1331			else
1332				printk(KERN_DEBUG "apm: received unknown "
1333				       "event 0x%02x\n", event);
1334		}
1335		if (ignore_bounce
1336		    && (time_after(jiffies, last_resume + bounce_interval)))
1337			ignore_bounce = 0;
1338
1339		switch (event) {
1340		case APM_SYS_STANDBY:
1341		case APM_USER_STANDBY:
1342			queue_event(event, NULL);
1343			if (standbys_pending <= 0)
1344				standby();
1345			break;
1346
1347		case APM_USER_SUSPEND:
1348#ifdef CONFIG_APM_IGNORE_USER_SUSPEND
1349			if (apm_info.connection_version > 0x100)
1350				set_system_power_state(APM_STATE_REJECT);
1351			break;
1352#endif
1353		case APM_SYS_SUSPEND:
1354			if (ignore_bounce) {
1355				if (apm_info.connection_version > 0x100)
1356					set_system_power_state(APM_STATE_REJECT);
1357				break;
1358			}
1359			/*
1360			 * If we are already processing a SUSPEND,
1361			 * then further SUSPEND events from the BIOS
1362			 * will be ignored.  We also return here to
1363			 * cope with the fact that the Thinkpads keep
1364			 * sending a SUSPEND event until something else
1365			 * happens!
1366			 */
1367			if (ignore_sys_suspend)
1368				return;
1369			ignore_sys_suspend = 1;
1370			queue_event(event, NULL);
1371			if (suspends_pending <= 0)
1372				(void) suspend(1);
1373			break;
1374
1375		case APM_NORMAL_RESUME:
1376		case APM_CRITICAL_RESUME:
1377		case APM_STANDBY_RESUME:
1378			ignore_sys_suspend = 0;
1379			last_resume = jiffies;
1380			ignore_bounce = 1;
1381			if ((event != APM_NORMAL_RESUME)
1382			    || (ignore_normal_resume == 0)) {
1383				dpm_resume_end(PMSG_RESUME);
1384				queue_event(event, NULL);
1385			}
1386			ignore_normal_resume = 0;
1387			break;
1388
1389		case APM_CAPABILITY_CHANGE:
1390		case APM_LOW_BATTERY:
1391		case APM_POWER_STATUS_CHANGE:
1392			queue_event(event, NULL);
1393			/* If needed, notify drivers here */
1394			break;
1395
1396		case APM_UPDATE_TIME:
1397			break;
1398
1399		case APM_CRITICAL_SUSPEND:
1400			/*
1401			 * We are not allowed to reject a critical suspend.
1402			 */
1403			(void)suspend(0);
1404			break;
1405		}
1406	}
1407}
1408
1409static void apm_event_handler(void)
1410{
1411	static int pending_count = 4;
1412	int err;
1413
1414	if ((standbys_pending > 0) || (suspends_pending > 0)) {
1415		if ((apm_info.connection_version > 0x100) &&
1416		    (pending_count-- <= 0)) {
1417			pending_count = 4;
1418			if (debug)
1419				printk(KERN_DEBUG "apm: setting state busy\n");
1420			err = set_system_power_state(APM_STATE_BUSY);
1421			if (err)
1422				apm_error("busy", err);
1423		}
1424	} else
1425		pending_count = 4;
1426	check_events();
1427}
1428
1429/*
1430 * This is the APM thread main loop.
1431 */
1432
1433static void apm_mainloop(void)
1434{
1435	DECLARE_WAITQUEUE(wait, current);
1436
1437	add_wait_queue(&apm_waitqueue, &wait);
1438	set_current_state(TASK_INTERRUPTIBLE);
1439	for (;;) {
1440		schedule_timeout(APM_CHECK_TIMEOUT);
1441		if (kthread_should_stop())
1442			break;
1443		/*
1444		 * Ok, check all events, check for idle (and mark us sleeping
1445		 * so as not to count towards the load average)..
1446		 */
1447		set_current_state(TASK_INTERRUPTIBLE);
1448		apm_event_handler();
1449	}
1450	remove_wait_queue(&apm_waitqueue, &wait);
1451}
1452
1453static int check_apm_user(struct apm_user *as, const char *func)
1454{
1455	if (as == NULL || as->magic != APM_BIOS_MAGIC) {
1456		pr_err("%s passed bad filp\n", func);
1457		return 1;
1458	}
1459	return 0;
1460}
1461
1462static ssize_t do_read(struct file *fp, char __user *buf, size_t count, loff_t *ppos)
1463{
1464	struct apm_user *as;
1465	int i;
1466	apm_event_t event;
1467
1468	as = fp->private_data;
1469	if (check_apm_user(as, "read"))
1470		return -EIO;
1471	if ((int)count < sizeof(apm_event_t))
1472		return -EINVAL;
1473	if ((queue_empty(as)) && (fp->f_flags & O_NONBLOCK))
1474		return -EAGAIN;
1475	wait_event_interruptible(apm_waitqueue, !queue_empty(as));
1476	i = count;
1477	while ((i >= sizeof(event)) && !queue_empty(as)) {
1478		event = get_queued_event(as);
1479		if (copy_to_user(buf, &event, sizeof(event))) {
1480			if (i < count)
1481				break;
1482			return -EFAULT;
1483		}
1484		switch (event) {
1485		case APM_SYS_SUSPEND:
1486		case APM_USER_SUSPEND:
1487			as->suspends_read++;
1488			break;
1489
1490		case APM_SYS_STANDBY:
1491		case APM_USER_STANDBY:
1492			as->standbys_read++;
1493			break;
1494		}
1495		buf += sizeof(event);
1496		i -= sizeof(event);
1497	}
1498	if (i < count)
1499		return count - i;
1500	if (signal_pending(current))
1501		return -ERESTARTSYS;
1502	return 0;
1503}
1504
1505static unsigned int do_poll(struct file *fp, poll_table *wait)
1506{
1507	struct apm_user *as;
1508
1509	as = fp->private_data;
1510	if (check_apm_user(as, "poll"))
1511		return 0;
1512	poll_wait(fp, &apm_waitqueue, wait);
1513	if (!queue_empty(as))
1514		return POLLIN | POLLRDNORM;
1515	return 0;
1516}
1517
1518static long do_ioctl(struct file *filp, u_int cmd, u_long arg)
1519{
1520	struct apm_user *as;
1521	int ret;
1522
1523	as = filp->private_data;
1524	if (check_apm_user(as, "ioctl"))
1525		return -EIO;
1526	if (!as->suser || !as->writer)
1527		return -EPERM;
1528	switch (cmd) {
1529	case APM_IOC_STANDBY:
1530		mutex_lock(&apm_mutex);
1531		if (as->standbys_read > 0) {
1532			as->standbys_read--;
1533			as->standbys_pending--;
1534			standbys_pending--;
1535		} else
1536			queue_event(APM_USER_STANDBY, as);
1537		if (standbys_pending <= 0)
1538			standby();
1539		mutex_unlock(&apm_mutex);
1540		break;
1541	case APM_IOC_SUSPEND:
1542		mutex_lock(&apm_mutex);
1543		if (as->suspends_read > 0) {
1544			as->suspends_read--;
1545			as->suspends_pending--;
1546			suspends_pending--;
1547		} else
1548			queue_event(APM_USER_SUSPEND, as);
1549		if (suspends_pending <= 0) {
1550			ret = suspend(1);
1551			mutex_unlock(&apm_mutex);
1552		} else {
1553			as->suspend_wait = 1;
1554			mutex_unlock(&apm_mutex);
1555			wait_event_interruptible(apm_suspend_waitqueue,
1556					as->suspend_wait == 0);
1557			ret = as->suspend_result;
1558		}
1559		return ret;
1560	default:
1561		return -ENOTTY;
1562	}
1563	return 0;
1564}
1565
1566static int do_release(struct inode *inode, struct file *filp)
1567{
1568	struct apm_user *as;
1569
1570	as = filp->private_data;
1571	if (check_apm_user(as, "release"))
1572		return 0;
1573	filp->private_data = NULL;
1574	if (as->standbys_pending > 0) {
1575		standbys_pending -= as->standbys_pending;
1576		if (standbys_pending <= 0)
1577			standby();
1578	}
1579	if (as->suspends_pending > 0) {
1580		suspends_pending -= as->suspends_pending;
1581		if (suspends_pending <= 0)
1582			(void) suspend(1);
1583	}
1584	spin_lock(&user_list_lock);
1585	if (user_list == as)
1586		user_list = as->next;
1587	else {
1588		struct apm_user *as1;
1589
1590		for (as1 = user_list;
1591		     (as1 != NULL) && (as1->next != as);
1592		     as1 = as1->next)
1593			;
1594		if (as1 == NULL)
1595			pr_err("filp not in user list\n");
1596		else
1597			as1->next = as->next;
1598	}
1599	spin_unlock(&user_list_lock);
1600	kfree(as);
1601	return 0;
1602}
1603
1604static int do_open(struct inode *inode, struct file *filp)
1605{
1606	struct apm_user *as;
1607
1608	as = kmalloc(sizeof(*as), GFP_KERNEL);
1609	if (as == NULL)
 
 
1610		return -ENOMEM;
1611
1612	as->magic = APM_BIOS_MAGIC;
1613	as->event_tail = as->event_head = 0;
1614	as->suspends_pending = as->standbys_pending = 0;
1615	as->suspends_read = as->standbys_read = 0;
1616	/*
1617	 * XXX - this is a tiny bit broken, when we consider BSD
1618	 * process accounting. If the device is opened by root, we
1619	 * instantly flag that we used superuser privs. Who knows,
1620	 * we might close the device immediately without doing a
1621	 * privileged operation -- cevans
1622	 */
1623	as->suser = capable(CAP_SYS_ADMIN);
1624	as->writer = (filp->f_mode & FMODE_WRITE) == FMODE_WRITE;
1625	as->reader = (filp->f_mode & FMODE_READ) == FMODE_READ;
1626	spin_lock(&user_list_lock);
1627	as->next = user_list;
1628	user_list = as;
1629	spin_unlock(&user_list_lock);
1630	filp->private_data = as;
1631	return 0;
1632}
1633
1634static int proc_apm_show(struct seq_file *m, void *v)
1635{
1636	unsigned short	bx;
1637	unsigned short	cx;
1638	unsigned short	dx;
1639	int		error;
1640	unsigned short  ac_line_status = 0xff;
1641	unsigned short  battery_status = 0xff;
1642	unsigned short  battery_flag   = 0xff;
1643	int		percentage     = -1;
1644	int             time_units     = -1;
1645	char            *units         = "?";
1646
1647	if ((num_online_cpus() == 1) &&
1648	    !(error = apm_get_power_status(&bx, &cx, &dx))) {
1649		ac_line_status = (bx >> 8) & 0xff;
1650		battery_status = bx & 0xff;
1651		if ((cx & 0xff) != 0xff)
1652			percentage = cx & 0xff;
1653
1654		if (apm_info.connection_version > 0x100) {
1655			battery_flag = (cx >> 8) & 0xff;
1656			if (dx != 0xffff) {
1657				units = (dx & 0x8000) ? "min" : "sec";
1658				time_units = dx & 0x7fff;
1659			}
1660		}
1661	}
1662	/* Arguments, with symbols from linux/apm_bios.h.  Information is
1663	   from the Get Power Status (0x0a) call unless otherwise noted.
1664
1665	   0) Linux driver version (this will change if format changes)
1666	   1) APM BIOS Version.  Usually 1.0, 1.1 or 1.2.
1667	   2) APM flags from APM Installation Check (0x00):
1668	      bit 0: APM_16_BIT_SUPPORT
1669	      bit 1: APM_32_BIT_SUPPORT
1670	      bit 2: APM_IDLE_SLOWS_CLOCK
1671	      bit 3: APM_BIOS_DISABLED
1672	      bit 4: APM_BIOS_DISENGAGED
1673	   3) AC line status
1674	      0x00: Off-line
1675	      0x01: On-line
1676	      0x02: On backup power (BIOS >= 1.1 only)
1677	      0xff: Unknown
1678	   4) Battery status
1679	      0x00: High
1680	      0x01: Low
1681	      0x02: Critical
1682	      0x03: Charging
1683	      0x04: Selected battery not present (BIOS >= 1.2 only)
1684	      0xff: Unknown
1685	   5) Battery flag
1686	      bit 0: High
1687	      bit 1: Low
1688	      bit 2: Critical
1689	      bit 3: Charging
1690	      bit 7: No system battery
1691	      0xff: Unknown
1692	   6) Remaining battery life (percentage of charge):
1693	      0-100: valid
1694	      -1: Unknown
1695	   7) Remaining battery life (time units):
1696	      Number of remaining minutes or seconds
1697	      -1: Unknown
1698	   8) min = minutes; sec = seconds */
1699
1700	seq_printf(m, "%s %d.%d 0x%02x 0x%02x 0x%02x 0x%02x %d%% %d %s\n",
1701		   driver_version,
1702		   (apm_info.bios.version >> 8) & 0xff,
1703		   apm_info.bios.version & 0xff,
1704		   apm_info.bios.flags,
1705		   ac_line_status,
1706		   battery_status,
1707		   battery_flag,
1708		   percentage,
1709		   time_units,
1710		   units);
1711	return 0;
1712}
1713
1714static int proc_apm_open(struct inode *inode, struct file *file)
1715{
1716	return single_open(file, proc_apm_show, NULL);
1717}
1718
1719static const struct file_operations apm_file_ops = {
1720	.owner		= THIS_MODULE,
1721	.open		= proc_apm_open,
1722	.read		= seq_read,
1723	.llseek		= seq_lseek,
1724	.release	= single_release,
1725};
1726
1727static int apm(void *unused)
1728{
1729	unsigned short	bx;
1730	unsigned short	cx;
1731	unsigned short	dx;
1732	int		error;
1733	char 		*power_stat;
1734	char 		*bat_stat;
1735
1736	/* 2002/08/01 - WT
1737	 * This is to avoid random crashes at boot time during initialization
1738	 * on SMP systems in case of "apm=power-off" mode. Seen on ASUS A7M266D.
1739	 * Some bioses don't like being called from CPU != 0.
1740	 * Method suggested by Ingo Molnar.
1741	 */
1742	set_cpus_allowed_ptr(current, cpumask_of(0));
1743	BUG_ON(smp_processor_id() != 0);
1744
1745	if (apm_info.connection_version == 0) {
1746		apm_info.connection_version = apm_info.bios.version;
1747		if (apm_info.connection_version > 0x100) {
1748			/*
1749			 * We only support BIOSs up to version 1.2
1750			 */
1751			if (apm_info.connection_version > 0x0102)
1752				apm_info.connection_version = 0x0102;
1753			error = apm_driver_version(&apm_info.connection_version);
1754			if (error != APM_SUCCESS) {
1755				apm_error("driver version", error);
1756				/* Fall back to an APM 1.0 connection. */
1757				apm_info.connection_version = 0x100;
1758			}
1759		}
1760	}
1761
1762	if (debug)
1763		printk(KERN_INFO "apm: Connection version %d.%d\n",
1764			(apm_info.connection_version >> 8) & 0xff,
1765			apm_info.connection_version & 0xff);
1766
1767#ifdef CONFIG_APM_DO_ENABLE
1768	if (apm_info.bios.flags & APM_BIOS_DISABLED) {
1769		/*
1770		 * This call causes my NEC UltraLite Versa 33/C to hang if it
1771		 * is booted with PM disabled but not in the docking station.
1772		 * Unfortunate ...
1773		 */
1774		error = apm_enable_power_management(1);
1775		if (error) {
1776			apm_error("enable power management", error);
1777			return -1;
1778		}
1779	}
1780#endif
1781
1782	if ((apm_info.bios.flags & APM_BIOS_DISENGAGED)
1783	    && (apm_info.connection_version > 0x0100)) {
1784		error = apm_engage_power_management(APM_DEVICE_ALL, 1);
1785		if (error) {
1786			apm_error("engage power management", error);
1787			return -1;
1788		}
1789	}
1790
1791	if (debug && (num_online_cpus() == 1 || smp)) {
1792		error = apm_get_power_status(&bx, &cx, &dx);
1793		if (error)
1794			printk(KERN_INFO "apm: power status not available\n");
1795		else {
1796			switch ((bx >> 8) & 0xff) {
1797			case 0:
1798				power_stat = "off line";
1799				break;
1800			case 1:
1801				power_stat = "on line";
1802				break;
1803			case 2:
1804				power_stat = "on backup power";
1805				break;
1806			default:
1807				power_stat = "unknown";
1808				break;
1809			}
1810			switch (bx & 0xff) {
1811			case 0:
1812				bat_stat = "high";
1813				break;
1814			case 1:
1815				bat_stat = "low";
1816				break;
1817			case 2:
1818				bat_stat = "critical";
1819				break;
1820			case 3:
1821				bat_stat = "charging";
1822				break;
1823			default:
1824				bat_stat = "unknown";
1825				break;
1826			}
1827			printk(KERN_INFO
1828			       "apm: AC %s, battery status %s, battery life ",
1829			       power_stat, bat_stat);
1830			if ((cx & 0xff) == 0xff)
1831				printk("unknown\n");
1832			else
1833				printk("%d%%\n", cx & 0xff);
1834			if (apm_info.connection_version > 0x100) {
1835				printk(KERN_INFO
1836				       "apm: battery flag 0x%02x, battery life ",
1837				       (cx >> 8) & 0xff);
1838				if (dx == 0xffff)
1839					printk("unknown\n");
1840				else
1841					printk("%d %s\n", dx & 0x7fff,
1842					       (dx & 0x8000) ?
1843					       "minutes" : "seconds");
1844			}
1845		}
1846	}
1847
1848	/* Install our power off handler.. */
1849	if (power_off)
1850		pm_power_off = apm_power_off;
1851
1852	if (num_online_cpus() == 1 || smp) {
1853#if defined(CONFIG_APM_DISPLAY_BLANK) && defined(CONFIG_VT)
1854		console_blank_hook = apm_console_blank;
1855#endif
1856		apm_mainloop();
1857#if defined(CONFIG_APM_DISPLAY_BLANK) && defined(CONFIG_VT)
1858		console_blank_hook = NULL;
1859#endif
1860	}
1861
1862	return 0;
1863}
1864
1865#ifndef MODULE
1866static int __init apm_setup(char *str)
1867{
1868	int invert;
1869
1870	while ((str != NULL) && (*str != '\0')) {
1871		if (strncmp(str, "off", 3) == 0)
1872			apm_disabled = 1;
1873		if (strncmp(str, "on", 2) == 0)
1874			apm_disabled = 0;
1875		if ((strncmp(str, "bounce-interval=", 16) == 0) ||
1876		    (strncmp(str, "bounce_interval=", 16) == 0))
1877			bounce_interval = simple_strtol(str + 16, NULL, 0);
1878		if ((strncmp(str, "idle-threshold=", 15) == 0) ||
1879		    (strncmp(str, "idle_threshold=", 15) == 0))
1880			idle_threshold = simple_strtol(str + 15, NULL, 0);
1881		if ((strncmp(str, "idle-period=", 12) == 0) ||
1882		    (strncmp(str, "idle_period=", 12) == 0))
1883			idle_period = simple_strtol(str + 12, NULL, 0);
1884		invert = (strncmp(str, "no-", 3) == 0) ||
1885			(strncmp(str, "no_", 3) == 0);
1886		if (invert)
1887			str += 3;
1888		if (strncmp(str, "debug", 5) == 0)
1889			debug = !invert;
1890		if ((strncmp(str, "power-off", 9) == 0) ||
1891		    (strncmp(str, "power_off", 9) == 0))
1892			power_off = !invert;
1893		if (strncmp(str, "smp", 3) == 0) {
1894			smp = !invert;
1895			idle_threshold = 100;
1896		}
1897		if ((strncmp(str, "allow-ints", 10) == 0) ||
1898		    (strncmp(str, "allow_ints", 10) == 0))
1899			apm_info.allow_ints = !invert;
1900		if ((strncmp(str, "broken-psr", 10) == 0) ||
1901		    (strncmp(str, "broken_psr", 10) == 0))
1902			apm_info.get_power_status_broken = !invert;
1903		if ((strncmp(str, "realmode-power-off", 18) == 0) ||
1904		    (strncmp(str, "realmode_power_off", 18) == 0))
1905			apm_info.realmode_power_off = !invert;
1906		str = strchr(str, ',');
1907		if (str != NULL)
1908			str += strspn(str, ", \t");
1909	}
1910	return 1;
1911}
1912
1913__setup("apm=", apm_setup);
1914#endif
1915
1916static const struct file_operations apm_bios_fops = {
1917	.owner		= THIS_MODULE,
1918	.read		= do_read,
1919	.poll		= do_poll,
1920	.unlocked_ioctl	= do_ioctl,
1921	.open		= do_open,
1922	.release	= do_release,
1923	.llseek		= noop_llseek,
1924};
1925
1926static struct miscdevice apm_device = {
1927	APM_MINOR_DEV,
1928	"apm_bios",
1929	&apm_bios_fops
1930};
1931
1932
1933/* Simple "print if true" callback */
1934static int __init print_if_true(const struct dmi_system_id *d)
1935{
1936	printk("%s\n", d->ident);
1937	return 0;
1938}
1939
1940/*
1941 * Some Bioses enable the PS/2 mouse (touchpad) at resume, even if it was
1942 * disabled before the suspend. Linux used to get terribly confused by that.
1943 */
1944static int __init broken_ps2_resume(const struct dmi_system_id *d)
1945{
1946	printk(KERN_INFO "%s machine detected. Mousepad Resume Bug "
1947	       "workaround hopefully not needed.\n", d->ident);
1948	return 0;
1949}
1950
1951/* Some bioses have a broken protected mode poweroff and need to use realmode */
1952static int __init set_realmode_power_off(const struct dmi_system_id *d)
1953{
1954	if (apm_info.realmode_power_off == 0) {
1955		apm_info.realmode_power_off = 1;
1956		printk(KERN_INFO "%s bios detected. "
1957		       "Using realmode poweroff only.\n", d->ident);
1958	}
1959	return 0;
1960}
1961
1962/* Some laptops require interrupts to be enabled during APM calls */
1963static int __init set_apm_ints(const struct dmi_system_id *d)
1964{
1965	if (apm_info.allow_ints == 0) {
1966		apm_info.allow_ints = 1;
1967		printk(KERN_INFO "%s machine detected. "
1968		       "Enabling interrupts during APM calls.\n", d->ident);
1969	}
1970	return 0;
1971}
1972
1973/* Some APM bioses corrupt memory or just plain do not work */
1974static int __init apm_is_horked(const struct dmi_system_id *d)
1975{
1976	if (apm_info.disabled == 0) {
1977		apm_info.disabled = 1;
1978		printk(KERN_INFO "%s machine detected. "
1979		       "Disabling APM.\n", d->ident);
1980	}
1981	return 0;
1982}
1983
1984static int __init apm_is_horked_d850md(const struct dmi_system_id *d)
1985{
1986	if (apm_info.disabled == 0) {
1987		apm_info.disabled = 1;
1988		printk(KERN_INFO "%s machine detected. "
1989		       "Disabling APM.\n", d->ident);
1990		printk(KERN_INFO "This bug is fixed in bios P15 which is available for\n");
1991		printk(KERN_INFO "download from support.intel.com\n");
1992	}
1993	return 0;
1994}
1995
1996/* Some APM bioses hang on APM idle calls */
1997static int __init apm_likes_to_melt(const struct dmi_system_id *d)
1998{
1999	if (apm_info.forbid_idle == 0) {
2000		apm_info.forbid_idle = 1;
2001		printk(KERN_INFO "%s machine detected. "
2002		       "Disabling APM idle calls.\n", d->ident);
2003	}
2004	return 0;
2005}
2006
2007/*
2008 *  Check for clue free BIOS implementations who use
2009 *  the following QA technique
2010 *
2011 *      [ Write BIOS Code ]<------
2012 *               |                ^
2013 *      < Does it Compile >----N--
2014 *               |Y               ^
2015 *	< Does it Boot Win98 >-N--
2016 *               |Y
2017 *           [Ship It]
2018 *
2019 *	Phoenix A04  08/24/2000 is known bad (Dell Inspiron 5000e)
2020 *	Phoenix A07  09/29/2000 is known good (Dell Inspiron 5000)
2021 */
2022static int __init broken_apm_power(const struct dmi_system_id *d)
2023{
2024	apm_info.get_power_status_broken = 1;
2025	printk(KERN_WARNING "BIOS strings suggest APM bugs, "
2026	       "disabling power status reporting.\n");
2027	return 0;
2028}
2029
2030/*
2031 * This bios swaps the APM minute reporting bytes over (Many sony laptops
2032 * have this problem).
2033 */
2034static int __init swab_apm_power_in_minutes(const struct dmi_system_id *d)
2035{
2036	apm_info.get_power_status_swabinminutes = 1;
2037	printk(KERN_WARNING "BIOS strings suggest APM reports battery life "
2038	       "in minutes and wrong byte order.\n");
2039	return 0;
2040}
2041
2042static struct dmi_system_id __initdata apm_dmi_table[] = {
2043	{
2044		print_if_true,
2045		KERN_WARNING "IBM T23 - BIOS 1.03b+ and controller firmware 1.02+ may be needed for Linux APM.",
2046		{	DMI_MATCH(DMI_SYS_VENDOR, "IBM"),
2047			DMI_MATCH(DMI_BIOS_VERSION, "1AET38WW (1.01b)"), },
2048	},
2049	{	/* Handle problems with APM on the C600 */
2050		broken_ps2_resume, "Dell Latitude C600",
2051		{	DMI_MATCH(DMI_SYS_VENDOR, "Dell"),
2052			DMI_MATCH(DMI_PRODUCT_NAME, "Latitude C600"), },
2053	},
2054	{	/* Allow interrupts during suspend on Dell Latitude laptops*/
2055		set_apm_ints, "Dell Latitude",
2056		{	DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
2057			DMI_MATCH(DMI_PRODUCT_NAME, "Latitude C510"), }
2058	},
2059	{	/* APM crashes */
2060		apm_is_horked, "Dell Inspiron 2500",
2061		{	DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
2062			DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 2500"),
2063			DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2064			DMI_MATCH(DMI_BIOS_VERSION, "A11"), },
2065	},
2066	{	/* Allow interrupts during suspend on Dell Inspiron laptops*/
2067		set_apm_ints, "Dell Inspiron", {
2068			DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
2069			DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 4000"), },
2070	},
2071	{	/* Handle problems with APM on Inspiron 5000e */
2072		broken_apm_power, "Dell Inspiron 5000e",
2073		{	DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2074			DMI_MATCH(DMI_BIOS_VERSION, "A04"),
2075			DMI_MATCH(DMI_BIOS_DATE, "08/24/2000"), },
2076	},
2077	{	/* Handle problems with APM on Inspiron 2500 */
2078		broken_apm_power, "Dell Inspiron 2500",
2079		{	DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2080			DMI_MATCH(DMI_BIOS_VERSION, "A12"),
2081			DMI_MATCH(DMI_BIOS_DATE, "02/04/2002"), },
2082	},
2083	{	/* APM crashes */
2084		apm_is_horked, "Dell Dimension 4100",
2085		{	DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
2086			DMI_MATCH(DMI_PRODUCT_NAME, "XPS-Z"),
2087			DMI_MATCH(DMI_BIOS_VENDOR, "Intel Corp."),
2088			DMI_MATCH(DMI_BIOS_VERSION, "A11"), },
2089	},
2090	{	/* Allow interrupts during suspend on Compaq Laptops*/
2091		set_apm_ints, "Compaq 12XL125",
2092		{	DMI_MATCH(DMI_SYS_VENDOR, "Compaq"),
2093			DMI_MATCH(DMI_PRODUCT_NAME, "Compaq PC"),
2094			DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2095			DMI_MATCH(DMI_BIOS_VERSION, "4.06"), },
2096	},
2097	{	/* Allow interrupts during APM or the clock goes slow */
2098		set_apm_ints, "ASUSTeK",
2099		{	DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK Computer Inc."),
2100			DMI_MATCH(DMI_PRODUCT_NAME, "L8400K series Notebook PC"), },
2101	},
2102	{	/* APM blows on shutdown */
2103		apm_is_horked, "ABIT KX7-333[R]",
2104		{	DMI_MATCH(DMI_BOARD_VENDOR, "ABIT"),
2105			DMI_MATCH(DMI_BOARD_NAME, "VT8367-8233A (KX7-333[R])"), },
2106	},
2107	{	/* APM crashes */
2108		apm_is_horked, "Trigem Delhi3",
2109		{	DMI_MATCH(DMI_SYS_VENDOR, "TriGem Computer, Inc"),
2110			DMI_MATCH(DMI_PRODUCT_NAME, "Delhi3"), },
2111	},
2112	{	/* APM crashes */
2113		apm_is_horked, "Fujitsu-Siemens",
2114		{	DMI_MATCH(DMI_BIOS_VENDOR, "hoenix/FUJITSU SIEMENS"),
2115			DMI_MATCH(DMI_BIOS_VERSION, "Version1.01"), },
2116	},
2117	{	/* APM crashes */
2118		apm_is_horked_d850md, "Intel D850MD",
2119		{	DMI_MATCH(DMI_BIOS_VENDOR, "Intel Corp."),
2120			DMI_MATCH(DMI_BIOS_VERSION, "MV85010A.86A.0016.P07.0201251536"), },
2121	},
2122	{	/* APM crashes */
2123		apm_is_horked, "Intel D810EMO",
2124		{	DMI_MATCH(DMI_BIOS_VENDOR, "Intel Corp."),
2125			DMI_MATCH(DMI_BIOS_VERSION, "MO81010A.86A.0008.P04.0004170800"), },
2126	},
2127	{	/* APM crashes */
2128		apm_is_horked, "Dell XPS-Z",
2129		{	DMI_MATCH(DMI_BIOS_VENDOR, "Intel Corp."),
2130			DMI_MATCH(DMI_BIOS_VERSION, "A11"),
2131			DMI_MATCH(DMI_PRODUCT_NAME, "XPS-Z"), },
2132	},
2133	{	/* APM crashes */
2134		apm_is_horked, "Sharp PC-PJ/AX",
2135		{	DMI_MATCH(DMI_SYS_VENDOR, "SHARP"),
2136			DMI_MATCH(DMI_PRODUCT_NAME, "PC-PJ/AX"),
2137			DMI_MATCH(DMI_BIOS_VENDOR, "SystemSoft"),
2138			DMI_MATCH(DMI_BIOS_VERSION, "Version R2.08"), },
2139	},
2140	{	/* APM crashes */
2141		apm_is_horked, "Dell Inspiron 2500",
2142		{	DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
2143			DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 2500"),
2144			DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2145			DMI_MATCH(DMI_BIOS_VERSION, "A11"), },
2146	},
2147	{	/* APM idle hangs */
2148		apm_likes_to_melt, "Jabil AMD",
2149		{	DMI_MATCH(DMI_BIOS_VENDOR, "American Megatrends Inc."),
2150			DMI_MATCH(DMI_BIOS_VERSION, "0AASNP06"), },
2151	},
2152	{	/* APM idle hangs */
2153		apm_likes_to_melt, "AMI Bios",
2154		{	DMI_MATCH(DMI_BIOS_VENDOR, "American Megatrends Inc."),
2155			DMI_MATCH(DMI_BIOS_VERSION, "0AASNP05"), },
2156	},
2157	{	/* Handle problems with APM on Sony Vaio PCG-N505X(DE) */
2158		swab_apm_power_in_minutes, "Sony VAIO",
2159		{	DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2160			DMI_MATCH(DMI_BIOS_VERSION, "R0206H"),
2161			DMI_MATCH(DMI_BIOS_DATE, "08/23/99"), },
2162	},
2163	{	/* Handle problems with APM on Sony Vaio PCG-N505VX */
2164		swab_apm_power_in_minutes, "Sony VAIO",
2165		{	DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2166			DMI_MATCH(DMI_BIOS_VERSION, "W2K06H0"),
2167			DMI_MATCH(DMI_BIOS_DATE, "02/03/00"), },
2168	},
2169	{	/* Handle problems with APM on Sony Vaio PCG-XG29 */
2170		swab_apm_power_in_minutes, "Sony VAIO",
2171		{	DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2172			DMI_MATCH(DMI_BIOS_VERSION, "R0117A0"),
2173			DMI_MATCH(DMI_BIOS_DATE, "04/25/00"), },
2174	},
2175	{	/* Handle problems with APM on Sony Vaio PCG-Z600NE */
2176		swab_apm_power_in_minutes, "Sony VAIO",
2177		{	DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2178			DMI_MATCH(DMI_BIOS_VERSION, "R0121Z1"),
2179			DMI_MATCH(DMI_BIOS_DATE, "05/11/00"), },
2180	},
2181	{	/* Handle problems with APM on Sony Vaio PCG-Z600NE */
2182		swab_apm_power_in_minutes, "Sony VAIO",
2183		{	DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2184			DMI_MATCH(DMI_BIOS_VERSION, "WME01Z1"),
2185			DMI_MATCH(DMI_BIOS_DATE, "08/11/00"), },
2186	},
2187	{	/* Handle problems with APM on Sony Vaio PCG-Z600LEK(DE) */
2188		swab_apm_power_in_minutes, "Sony VAIO",
2189		{	DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2190			DMI_MATCH(DMI_BIOS_VERSION, "R0206Z3"),
2191			DMI_MATCH(DMI_BIOS_DATE, "12/25/00"), },
2192	},
2193	{	/* Handle problems with APM on Sony Vaio PCG-Z505LS */
2194		swab_apm_power_in_minutes, "Sony VAIO",
2195		{	DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2196			DMI_MATCH(DMI_BIOS_VERSION, "R0203D0"),
2197			DMI_MATCH(DMI_BIOS_DATE, "05/12/00"), },
2198	},
2199	{	/* Handle problems with APM on Sony Vaio PCG-Z505LS */
2200		swab_apm_power_in_minutes, "Sony VAIO",
2201		{	DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2202			DMI_MATCH(DMI_BIOS_VERSION, "R0203Z3"),
2203			DMI_MATCH(DMI_BIOS_DATE, "08/25/00"), },
2204	},
2205	{	/* Handle problems with APM on Sony Vaio PCG-Z505LS (with updated BIOS) */
2206		swab_apm_power_in_minutes, "Sony VAIO",
2207		{	DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2208			DMI_MATCH(DMI_BIOS_VERSION, "R0209Z3"),
2209			DMI_MATCH(DMI_BIOS_DATE, "05/12/01"), },
2210	},
2211	{	/* Handle problems with APM on Sony Vaio PCG-F104K */
2212		swab_apm_power_in_minutes, "Sony VAIO",
2213		{	DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2214			DMI_MATCH(DMI_BIOS_VERSION, "R0204K2"),
2215			DMI_MATCH(DMI_BIOS_DATE, "08/28/00"), },
2216	},
2217
2218	{	/* Handle problems with APM on Sony Vaio PCG-C1VN/C1VE */
2219		swab_apm_power_in_minutes, "Sony VAIO",
2220		{	DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2221			DMI_MATCH(DMI_BIOS_VERSION, "R0208P1"),
2222			DMI_MATCH(DMI_BIOS_DATE, "11/09/00"), },
2223	},
2224	{	/* Handle problems with APM on Sony Vaio PCG-C1VE */
2225		swab_apm_power_in_minutes, "Sony VAIO",
2226		{	DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2227			DMI_MATCH(DMI_BIOS_VERSION, "R0204P1"),
2228			DMI_MATCH(DMI_BIOS_DATE, "09/12/00"), },
2229	},
2230	{	/* Handle problems with APM on Sony Vaio PCG-C1VE */
2231		swab_apm_power_in_minutes, "Sony VAIO",
2232		{	DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2233			DMI_MATCH(DMI_BIOS_VERSION, "WXPO1Z3"),
2234			DMI_MATCH(DMI_BIOS_DATE, "10/26/01"), },
2235	},
2236	{	/* broken PM poweroff bios */
2237		set_realmode_power_off, "Award Software v4.60 PGMA",
2238		{	DMI_MATCH(DMI_BIOS_VENDOR, "Award Software International, Inc."),
2239			DMI_MATCH(DMI_BIOS_VERSION, "4.60 PGMA"),
2240			DMI_MATCH(DMI_BIOS_DATE, "134526184"), },
2241	},
2242
2243	/* Generic per vendor APM settings  */
2244
2245	{	/* Allow interrupts during suspend on IBM laptops */
2246		set_apm_ints, "IBM",
2247		{	DMI_MATCH(DMI_SYS_VENDOR, "IBM"), },
2248	},
2249
2250	{ }
2251};
2252
2253/*
2254 * Just start the APM thread. We do NOT want to do APM BIOS
2255 * calls from anything but the APM thread, if for no other reason
2256 * than the fact that we don't trust the APM BIOS. This way,
2257 * most common APM BIOS problems that lead to protection errors
2258 * etc will have at least some level of being contained...
2259 *
2260 * In short, if something bad happens, at least we have a choice
2261 * of just killing the apm thread..
2262 */
2263static int __init apm_init(void)
2264{
2265	struct desc_struct *gdt;
2266	int err;
2267
2268	dmi_check_system(apm_dmi_table);
2269
2270	if (apm_info.bios.version == 0 || paravirt_enabled() || machine_is_olpc()) {
2271		printk(KERN_INFO "apm: BIOS not found.\n");
2272		return -ENODEV;
2273	}
2274	printk(KERN_INFO
2275	       "apm: BIOS version %d.%d Flags 0x%02x (Driver version %s)\n",
2276	       ((apm_info.bios.version >> 8) & 0xff),
2277	       (apm_info.bios.version & 0xff),
2278	       apm_info.bios.flags,
2279	       driver_version);
2280	if ((apm_info.bios.flags & APM_32_BIT_SUPPORT) == 0) {
2281		printk(KERN_INFO "apm: no 32 bit BIOS support\n");
2282		return -ENODEV;
2283	}
2284
2285	if (allow_ints)
2286		apm_info.allow_ints = 1;
2287	if (broken_psr)
2288		apm_info.get_power_status_broken = 1;
2289	if (realmode_power_off)
2290		apm_info.realmode_power_off = 1;
2291	/* User can override, but default is to trust DMI */
2292	if (apm_disabled != -1)
2293		apm_info.disabled = apm_disabled;
2294
2295	/*
2296	 * Fix for the Compaq Contura 3/25c which reports BIOS version 0.1
2297	 * but is reportedly a 1.0 BIOS.
2298	 */
2299	if (apm_info.bios.version == 0x001)
2300		apm_info.bios.version = 0x100;
2301
2302	/* BIOS < 1.2 doesn't set cseg_16_len */
2303	if (apm_info.bios.version < 0x102)
2304		apm_info.bios.cseg_16_len = 0; /* 64k */
2305
2306	if (debug) {
2307		printk(KERN_INFO "apm: entry %x:%x cseg16 %x dseg %x",
2308			apm_info.bios.cseg, apm_info.bios.offset,
2309			apm_info.bios.cseg_16, apm_info.bios.dseg);
2310		if (apm_info.bios.version > 0x100)
2311			printk(" cseg len %x, dseg len %x",
2312				apm_info.bios.cseg_len,
2313				apm_info.bios.dseg_len);
2314		if (apm_info.bios.version > 0x101)
2315			printk(" cseg16 len %x", apm_info.bios.cseg_16_len);
2316		printk("\n");
2317	}
2318
2319	if (apm_info.disabled) {
2320		pr_notice("disabled on user request.\n");
2321		return -ENODEV;
2322	}
2323	if ((num_online_cpus() > 1) && !power_off && !smp) {
2324		pr_notice("disabled - APM is not SMP safe.\n");
2325		apm_info.disabled = 1;
2326		return -ENODEV;
2327	}
2328	if (!acpi_disabled) {
2329		pr_notice("overridden by ACPI.\n");
2330		apm_info.disabled = 1;
2331		return -ENODEV;
2332	}
2333
2334	/*
2335	 * Set up the long jump entry point to the APM BIOS, which is called
2336	 * from inline assembly.
2337	 */
2338	apm_bios_entry.offset = apm_info.bios.offset;
2339	apm_bios_entry.segment = APM_CS;
2340
2341	/*
2342	 * The APM 1.1 BIOS is supposed to provide limit information that it
2343	 * recognizes.  Many machines do this correctly, but many others do
2344	 * not restrict themselves to their claimed limit.  When this happens,
2345	 * they will cause a segmentation violation in the kernel at boot time.
2346	 * Most BIOS's, however, will respect a 64k limit, so we use that.
2347	 *
2348	 * Note we only set APM segments on CPU zero, since we pin the APM
2349	 * code to that CPU.
2350	 */
2351	gdt = get_cpu_gdt_table(0);
2352	set_desc_base(&gdt[APM_CS >> 3],
2353		 (unsigned long)__va((unsigned long)apm_info.bios.cseg << 4));
2354	set_desc_base(&gdt[APM_CS_16 >> 3],
2355		 (unsigned long)__va((unsigned long)apm_info.bios.cseg_16 << 4));
2356	set_desc_base(&gdt[APM_DS >> 3],
2357		 (unsigned long)__va((unsigned long)apm_info.bios.dseg << 4));
2358
2359	proc_create("apm", 0, NULL, &apm_file_ops);
2360
2361	kapmd_task = kthread_create(apm, NULL, "kapmd");
2362	if (IS_ERR(kapmd_task)) {
2363		pr_err("disabled - Unable to start kernel thread\n");
 
2364		err = PTR_ERR(kapmd_task);
2365		kapmd_task = NULL;
2366		remove_proc_entry("apm", NULL);
2367		return err;
2368	}
2369	wake_up_process(kapmd_task);
2370
2371	if (num_online_cpus() > 1 && !smp) {
2372		printk(KERN_NOTICE
2373		       "apm: disabled - APM is not SMP safe (power off active).\n");
2374		return 0;
2375	}
2376
2377	/*
2378	 * Note we don't actually care if the misc_device cannot be registered.
2379	 * this driver can do its job without it, even if userspace can't
2380	 * control it.  just log the error
2381	 */
2382	if (misc_register(&apm_device))
2383		printk(KERN_WARNING "apm: Could not register misc device.\n");
2384
2385	if (HZ != 100)
2386		idle_period = (idle_period * HZ) / 100;
2387	if (idle_threshold < 100) {
2388		if (!cpuidle_register_driver(&apm_idle_driver))
2389			if (cpuidle_register_device(&apm_cpuidle_device))
2390				cpuidle_unregister_driver(&apm_idle_driver);
2391	}
2392
2393	return 0;
2394}
2395
2396static void __exit apm_exit(void)
2397{
2398	int error;
2399
2400	cpuidle_unregister_device(&apm_cpuidle_device);
2401	cpuidle_unregister_driver(&apm_idle_driver);
2402
 
 
 
 
 
 
2403	if (((apm_info.bios.flags & APM_BIOS_DISENGAGED) == 0)
2404	    && (apm_info.connection_version > 0x0100)) {
2405		error = apm_engage_power_management(APM_DEVICE_ALL, 0);
2406		if (error)
2407			apm_error("disengage power management", error);
2408	}
2409	misc_deregister(&apm_device);
2410	remove_proc_entry("apm", NULL);
2411	if (power_off)
2412		pm_power_off = NULL;
2413	if (kapmd_task) {
2414		kthread_stop(kapmd_task);
2415		kapmd_task = NULL;
2416	}
2417}
2418
2419module_init(apm_init);
2420module_exit(apm_exit);
2421
2422MODULE_AUTHOR("Stephen Rothwell");
2423MODULE_DESCRIPTION("Advanced Power Management");
2424MODULE_LICENSE("GPL");
2425module_param(debug, bool, 0644);
2426MODULE_PARM_DESC(debug, "Enable debug mode");
2427module_param(power_off, bool, 0444);
2428MODULE_PARM_DESC(power_off, "Enable power off");
2429module_param(bounce_interval, int, 0444);
2430MODULE_PARM_DESC(bounce_interval,
2431		"Set the number of ticks to ignore suspend bounces");
2432module_param(allow_ints, bool, 0444);
2433MODULE_PARM_DESC(allow_ints, "Allow interrupts during BIOS calls");
2434module_param(broken_psr, bool, 0444);
2435MODULE_PARM_DESC(broken_psr, "BIOS has a broken GetPowerStatus call");
2436module_param(realmode_power_off, bool, 0444);
2437MODULE_PARM_DESC(realmode_power_off,
2438		"Switch to real mode before powering off");
2439module_param(idle_threshold, int, 0444);
2440MODULE_PARM_DESC(idle_threshold,
2441	"System idle percentage above which to make APM BIOS idle calls");
2442module_param(idle_period, int, 0444);
2443MODULE_PARM_DESC(idle_period,
2444	"Period (in sec/100) over which to caculate the idle percentage");
2445module_param(smp, bool, 0444);
2446MODULE_PARM_DESC(smp,
2447	"Set this to enable APM use on an SMP platform. Use with caution on older systems");
2448MODULE_ALIAS_MISCDEV(APM_MINOR_DEV);