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v4.10.11
   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 <linux/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, utime;
 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, &utime, &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		if (!call.err)
1047			return APM_NO_ERROR;
1048		return call.err;
1049	}
1050	*status = call.ebx;
1051	*bat = call.ecx;
1052	if (apm_info.get_power_status_swabinminutes) {
1053		*life = swab16((u16)call.edx);
1054		*life |= 0x8000;
1055	} else
1056		*life = call.edx;
1057	return APM_SUCCESS;
1058}
1059
1060#if 0
1061static int apm_get_battery_status(u_short which, u_short *status,
1062				  u_short *bat, u_short *life, u_short *nbat)
1063{
1064	u32 eax;
1065	u32 ebx;
1066	u32 ecx;
1067	u32 edx;
1068	u32 esi;
1069
1070	if (apm_info.connection_version < 0x0102) {
1071		/* pretend we only have one battery. */
1072		if (which != 1)
1073			return APM_BAD_DEVICE;
1074		*nbat = 1;
1075		return apm_get_power_status(status, bat, life);
1076	}
1077
1078	if (apm_bios_call(APM_FUNC_GET_STATUS, (0x8000 | (which)), 0, &eax,
1079			  &ebx, &ecx, &edx, &esi))
1080		return (eax >> 8) & 0xff;
1081	*status = ebx;
1082	*bat = ecx;
1083	*life = edx;
1084	*nbat = esi;
1085	return APM_SUCCESS;
1086}
1087#endif
1088
1089/**
1090 *	apm_engage_power_management	-	enable PM on a device
1091 *	@device: identity of device
1092 *	@enable: on/off
1093 *
1094 *	Activate or deactivate power management on either a specific device
1095 *	or the entire system (%APM_DEVICE_ALL).
1096 */
1097
1098static int apm_engage_power_management(u_short device, int enable)
1099{
1100	u32 eax;
1101	int err;
1102
1103	if ((enable == 0) && (device == APM_DEVICE_ALL)
1104	    && (apm_info.bios.flags & APM_BIOS_DISABLED))
1105		return APM_DISABLED;
1106	if (apm_bios_call_simple(APM_FUNC_ENGAGE_PM, device, enable,
1107				 &eax, &err))
1108		return err;
1109	if (device == APM_DEVICE_ALL) {
1110		if (enable)
1111			apm_info.bios.flags &= ~APM_BIOS_DISENGAGED;
1112		else
1113			apm_info.bios.flags |= APM_BIOS_DISENGAGED;
1114	}
1115	return APM_SUCCESS;
1116}
1117
1118#if defined(CONFIG_APM_DISPLAY_BLANK) && defined(CONFIG_VT)
1119
1120/**
1121 *	apm_console_blank	-	blank the display
1122 *	@blank: on/off
1123 *
1124 *	Attempt to blank the console, firstly by blanking just video device
1125 *	zero, and if that fails (some BIOSes don't support it) then it blanks
1126 *	all video devices. Typically the BIOS will do laptop backlight and
1127 *	monitor powerdown for us.
1128 */
1129
1130static int apm_console_blank(int blank)
1131{
1132	int error = APM_NOT_ENGAGED; /* silence gcc */
1133	int i;
1134	u_short state;
1135	static const u_short dev[3] = { 0x100, 0x1FF, 0x101 };
1136
1137	state = blank ? APM_STATE_STANDBY : APM_STATE_READY;
1138
1139	for (i = 0; i < ARRAY_SIZE(dev); i++) {
1140		error = set_power_state(dev[i], state);
1141
1142		if ((error == APM_SUCCESS) || (error == APM_NO_ERROR))
1143			return 1;
1144
1145		if (error == APM_NOT_ENGAGED)
1146			break;
1147	}
1148
1149	if (error == APM_NOT_ENGAGED) {
1150		static int tried;
1151		int eng_error;
1152		if (tried++ == 0) {
1153			eng_error = apm_engage_power_management(APM_DEVICE_ALL, 1);
1154			if (eng_error) {
1155				apm_error("set display", error);
1156				apm_error("engage interface", eng_error);
1157				return 0;
1158			} else
1159				return apm_console_blank(blank);
1160		}
1161	}
1162	apm_error("set display", error);
1163	return 0;
1164}
1165#endif
1166
1167static int queue_empty(struct apm_user *as)
1168{
1169	return as->event_head == as->event_tail;
1170}
1171
1172static apm_event_t get_queued_event(struct apm_user *as)
1173{
1174	if (++as->event_tail >= APM_MAX_EVENTS)
1175		as->event_tail = 0;
1176	return as->events[as->event_tail];
1177}
1178
1179static void queue_event(apm_event_t event, struct apm_user *sender)
1180{
1181	struct apm_user *as;
1182
1183	spin_lock(&user_list_lock);
1184	if (user_list == NULL)
1185		goto out;
1186	for (as = user_list; as != NULL; as = as->next) {
1187		if ((as == sender) || (!as->reader))
1188			continue;
1189		if (++as->event_head >= APM_MAX_EVENTS)
1190			as->event_head = 0;
1191
1192		if (as->event_head == as->event_tail) {
1193			static int notified;
1194
1195			if (notified++ == 0)
1196				pr_err("an event queue overflowed\n");
1197			if (++as->event_tail >= APM_MAX_EVENTS)
1198				as->event_tail = 0;
1199		}
1200		as->events[as->event_head] = event;
1201		if (!as->suser || !as->writer)
1202			continue;
1203		switch (event) {
1204		case APM_SYS_SUSPEND:
1205		case APM_USER_SUSPEND:
1206			as->suspends_pending++;
1207			suspends_pending++;
1208			break;
1209
1210		case APM_SYS_STANDBY:
1211		case APM_USER_STANDBY:
1212			as->standbys_pending++;
1213			standbys_pending++;
1214			break;
1215		}
1216	}
1217	wake_up_interruptible(&apm_waitqueue);
1218out:
1219	spin_unlock(&user_list_lock);
1220}
1221
1222static void reinit_timer(void)
1223{
1224#ifdef INIT_TIMER_AFTER_SUSPEND
1225	unsigned long flags;
1226
1227	raw_spin_lock_irqsave(&i8253_lock, flags);
1228	/* set the clock to HZ */
1229	outb_p(0x34, PIT_MODE);		/* binary, mode 2, LSB/MSB, ch 0 */
1230	udelay(10);
1231	outb_p(LATCH & 0xff, PIT_CH0);	/* LSB */
1232	udelay(10);
1233	outb_p(LATCH >> 8, PIT_CH0);	/* MSB */
1234	udelay(10);
1235	raw_spin_unlock_irqrestore(&i8253_lock, flags);
1236#endif
1237}
1238
1239static int suspend(int vetoable)
1240{
1241	int err;
1242	struct apm_user	*as;
1243
1244	dpm_suspend_start(PMSG_SUSPEND);
1245	dpm_suspend_end(PMSG_SUSPEND);
1246
1247	local_irq_disable();
1248	syscore_suspend();
1249
1250	local_irq_enable();
1251
1252	save_processor_state();
1253	err = set_system_power_state(APM_STATE_SUSPEND);
1254	ignore_normal_resume = 1;
1255	restore_processor_state();
1256
1257	local_irq_disable();
1258	reinit_timer();
1259
1260	if (err == APM_NO_ERROR)
1261		err = APM_SUCCESS;
1262	if (err != APM_SUCCESS)
1263		apm_error("suspend", err);
1264	err = (err == APM_SUCCESS) ? 0 : -EIO;
1265
1266	syscore_resume();
1267	local_irq_enable();
1268
1269	dpm_resume_start(PMSG_RESUME);
1270	dpm_resume_end(PMSG_RESUME);
1271
1272	queue_event(APM_NORMAL_RESUME, NULL);
1273	spin_lock(&user_list_lock);
1274	for (as = user_list; as != NULL; as = as->next) {
1275		as->suspend_wait = 0;
1276		as->suspend_result = err;
1277	}
1278	spin_unlock(&user_list_lock);
1279	wake_up_interruptible(&apm_suspend_waitqueue);
1280	return err;
1281}
1282
1283static void standby(void)
1284{
1285	int err;
1286
1287	dpm_suspend_end(PMSG_SUSPEND);
1288
1289	local_irq_disable();
1290	syscore_suspend();
1291	local_irq_enable();
1292
1293	err = set_system_power_state(APM_STATE_STANDBY);
1294	if ((err != APM_SUCCESS) && (err != APM_NO_ERROR))
1295		apm_error("standby", err);
1296
1297	local_irq_disable();
1298	syscore_resume();
1299	local_irq_enable();
1300
1301	dpm_resume_start(PMSG_RESUME);
1302}
1303
1304static apm_event_t get_event(void)
1305{
1306	int error;
1307	apm_event_t event = APM_NO_EVENTS; /* silence gcc */
1308	apm_eventinfo_t	info;
1309
1310	static int notified;
1311
1312	/* we don't use the eventinfo */
1313	error = apm_get_event(&event, &info);
1314	if (error == APM_SUCCESS)
1315		return event;
1316
1317	if ((error != APM_NO_EVENTS) && (notified++ == 0))
1318		apm_error("get_event", error);
1319
1320	return 0;
1321}
1322
1323static void check_events(void)
1324{
1325	apm_event_t event;
1326	static unsigned long last_resume;
1327	static int ignore_bounce;
1328
1329	while ((event = get_event()) != 0) {
1330		if (debug) {
1331			if (event <= NR_APM_EVENT_NAME)
1332				printk(KERN_DEBUG "apm: received %s notify\n",
1333				       apm_event_name[event - 1]);
1334			else
1335				printk(KERN_DEBUG "apm: received unknown "
1336				       "event 0x%02x\n", event);
1337		}
1338		if (ignore_bounce
1339		    && (time_after(jiffies, last_resume + bounce_interval)))
1340			ignore_bounce = 0;
1341
1342		switch (event) {
1343		case APM_SYS_STANDBY:
1344		case APM_USER_STANDBY:
1345			queue_event(event, NULL);
1346			if (standbys_pending <= 0)
1347				standby();
1348			break;
1349
1350		case APM_USER_SUSPEND:
1351#ifdef CONFIG_APM_IGNORE_USER_SUSPEND
1352			if (apm_info.connection_version > 0x100)
1353				set_system_power_state(APM_STATE_REJECT);
1354			break;
1355#endif
1356		case APM_SYS_SUSPEND:
1357			if (ignore_bounce) {
1358				if (apm_info.connection_version > 0x100)
1359					set_system_power_state(APM_STATE_REJECT);
1360				break;
1361			}
1362			/*
1363			 * If we are already processing a SUSPEND,
1364			 * then further SUSPEND events from the BIOS
1365			 * will be ignored.  We also return here to
1366			 * cope with the fact that the Thinkpads keep
1367			 * sending a SUSPEND event until something else
1368			 * happens!
1369			 */
1370			if (ignore_sys_suspend)
1371				return;
1372			ignore_sys_suspend = 1;
1373			queue_event(event, NULL);
1374			if (suspends_pending <= 0)
1375				(void) suspend(1);
1376			break;
1377
1378		case APM_NORMAL_RESUME:
1379		case APM_CRITICAL_RESUME:
1380		case APM_STANDBY_RESUME:
1381			ignore_sys_suspend = 0;
1382			last_resume = jiffies;
1383			ignore_bounce = 1;
1384			if ((event != APM_NORMAL_RESUME)
1385			    || (ignore_normal_resume == 0)) {
1386				dpm_resume_end(PMSG_RESUME);
1387				queue_event(event, NULL);
1388			}
1389			ignore_normal_resume = 0;
1390			break;
1391
1392		case APM_CAPABILITY_CHANGE:
1393		case APM_LOW_BATTERY:
1394		case APM_POWER_STATUS_CHANGE:
1395			queue_event(event, NULL);
1396			/* If needed, notify drivers here */
1397			break;
1398
1399		case APM_UPDATE_TIME:
1400			break;
1401
1402		case APM_CRITICAL_SUSPEND:
1403			/*
1404			 * We are not allowed to reject a critical suspend.
1405			 */
1406			(void)suspend(0);
1407			break;
1408		}
1409	}
1410}
1411
1412static void apm_event_handler(void)
1413{
1414	static int pending_count = 4;
1415	int err;
1416
1417	if ((standbys_pending > 0) || (suspends_pending > 0)) {
1418		if ((apm_info.connection_version > 0x100) &&
1419		    (pending_count-- <= 0)) {
1420			pending_count = 4;
1421			if (debug)
1422				printk(KERN_DEBUG "apm: setting state busy\n");
1423			err = set_system_power_state(APM_STATE_BUSY);
1424			if (err)
1425				apm_error("busy", err);
1426		}
1427	} else
1428		pending_count = 4;
1429	check_events();
1430}
1431
1432/*
1433 * This is the APM thread main loop.
1434 */
1435
1436static void apm_mainloop(void)
1437{
1438	DECLARE_WAITQUEUE(wait, current);
1439
1440	add_wait_queue(&apm_waitqueue, &wait);
1441	set_current_state(TASK_INTERRUPTIBLE);
1442	for (;;) {
1443		schedule_timeout(APM_CHECK_TIMEOUT);
1444		if (kthread_should_stop())
1445			break;
1446		/*
1447		 * Ok, check all events, check for idle (and mark us sleeping
1448		 * so as not to count towards the load average)..
1449		 */
1450		set_current_state(TASK_INTERRUPTIBLE);
1451		apm_event_handler();
1452	}
1453	remove_wait_queue(&apm_waitqueue, &wait);
1454}
1455
1456static int check_apm_user(struct apm_user *as, const char *func)
1457{
1458	if (as == NULL || as->magic != APM_BIOS_MAGIC) {
1459		pr_err("%s passed bad filp\n", func);
1460		return 1;
1461	}
1462	return 0;
1463}
1464
1465static ssize_t do_read(struct file *fp, char __user *buf, size_t count, loff_t *ppos)
1466{
1467	struct apm_user *as;
1468	int i;
1469	apm_event_t event;
1470
1471	as = fp->private_data;
1472	if (check_apm_user(as, "read"))
1473		return -EIO;
1474	if ((int)count < sizeof(apm_event_t))
1475		return -EINVAL;
1476	if ((queue_empty(as)) && (fp->f_flags & O_NONBLOCK))
1477		return -EAGAIN;
1478	wait_event_interruptible(apm_waitqueue, !queue_empty(as));
1479	i = count;
1480	while ((i >= sizeof(event)) && !queue_empty(as)) {
1481		event = get_queued_event(as);
1482		if (copy_to_user(buf, &event, sizeof(event))) {
1483			if (i < count)
1484				break;
1485			return -EFAULT;
1486		}
1487		switch (event) {
1488		case APM_SYS_SUSPEND:
1489		case APM_USER_SUSPEND:
1490			as->suspends_read++;
1491			break;
1492
1493		case APM_SYS_STANDBY:
1494		case APM_USER_STANDBY:
1495			as->standbys_read++;
1496			break;
1497		}
1498		buf += sizeof(event);
1499		i -= sizeof(event);
1500	}
1501	if (i < count)
1502		return count - i;
1503	if (signal_pending(current))
1504		return -ERESTARTSYS;
1505	return 0;
1506}
1507
1508static unsigned int do_poll(struct file *fp, poll_table *wait)
1509{
1510	struct apm_user *as;
1511
1512	as = fp->private_data;
1513	if (check_apm_user(as, "poll"))
1514		return 0;
1515	poll_wait(fp, &apm_waitqueue, wait);
1516	if (!queue_empty(as))
1517		return POLLIN | POLLRDNORM;
1518	return 0;
1519}
1520
1521static long do_ioctl(struct file *filp, u_int cmd, u_long arg)
1522{
1523	struct apm_user *as;
1524	int ret;
1525
1526	as = filp->private_data;
1527	if (check_apm_user(as, "ioctl"))
1528		return -EIO;
1529	if (!as->suser || !as->writer)
1530		return -EPERM;
1531	switch (cmd) {
1532	case APM_IOC_STANDBY:
1533		mutex_lock(&apm_mutex);
1534		if (as->standbys_read > 0) {
1535			as->standbys_read--;
1536			as->standbys_pending--;
1537			standbys_pending--;
1538		} else
1539			queue_event(APM_USER_STANDBY, as);
1540		if (standbys_pending <= 0)
1541			standby();
1542		mutex_unlock(&apm_mutex);
1543		break;
1544	case APM_IOC_SUSPEND:
1545		mutex_lock(&apm_mutex);
1546		if (as->suspends_read > 0) {
1547			as->suspends_read--;
1548			as->suspends_pending--;
1549			suspends_pending--;
1550		} else
1551			queue_event(APM_USER_SUSPEND, as);
1552		if (suspends_pending <= 0) {
1553			ret = suspend(1);
1554			mutex_unlock(&apm_mutex);
1555		} else {
1556			as->suspend_wait = 1;
1557			mutex_unlock(&apm_mutex);
1558			wait_event_interruptible(apm_suspend_waitqueue,
1559					as->suspend_wait == 0);
1560			ret = as->suspend_result;
1561		}
1562		return ret;
1563	default:
1564		return -ENOTTY;
1565	}
1566	return 0;
1567}
1568
1569static int do_release(struct inode *inode, struct file *filp)
1570{
1571	struct apm_user *as;
1572
1573	as = filp->private_data;
1574	if (check_apm_user(as, "release"))
1575		return 0;
1576	filp->private_data = NULL;
1577	if (as->standbys_pending > 0) {
1578		standbys_pending -= as->standbys_pending;
1579		if (standbys_pending <= 0)
1580			standby();
1581	}
1582	if (as->suspends_pending > 0) {
1583		suspends_pending -= as->suspends_pending;
1584		if (suspends_pending <= 0)
1585			(void) suspend(1);
1586	}
1587	spin_lock(&user_list_lock);
1588	if (user_list == as)
1589		user_list = as->next;
1590	else {
1591		struct apm_user *as1;
1592
1593		for (as1 = user_list;
1594		     (as1 != NULL) && (as1->next != as);
1595		     as1 = as1->next)
1596			;
1597		if (as1 == NULL)
1598			pr_err("filp not in user list\n");
1599		else
1600			as1->next = as->next;
1601	}
1602	spin_unlock(&user_list_lock);
1603	kfree(as);
1604	return 0;
1605}
1606
1607static int do_open(struct inode *inode, struct file *filp)
1608{
1609	struct apm_user *as;
1610
1611	as = kmalloc(sizeof(*as), GFP_KERNEL);
1612	if (as == NULL)
1613		return -ENOMEM;
1614
1615	as->magic = APM_BIOS_MAGIC;
1616	as->event_tail = as->event_head = 0;
1617	as->suspends_pending = as->standbys_pending = 0;
1618	as->suspends_read = as->standbys_read = 0;
1619	/*
1620	 * XXX - this is a tiny bit broken, when we consider BSD
1621	 * process accounting. If the device is opened by root, we
1622	 * instantly flag that we used superuser privs. Who knows,
1623	 * we might close the device immediately without doing a
1624	 * privileged operation -- cevans
1625	 */
1626	as->suser = capable(CAP_SYS_ADMIN);
1627	as->writer = (filp->f_mode & FMODE_WRITE) == FMODE_WRITE;
1628	as->reader = (filp->f_mode & FMODE_READ) == FMODE_READ;
1629	spin_lock(&user_list_lock);
1630	as->next = user_list;
1631	user_list = as;
1632	spin_unlock(&user_list_lock);
1633	filp->private_data = as;
1634	return 0;
1635}
1636
1637static int proc_apm_show(struct seq_file *m, void *v)
1638{
1639	unsigned short	bx;
1640	unsigned short	cx;
1641	unsigned short	dx;
1642	int		error;
1643	unsigned short  ac_line_status = 0xff;
1644	unsigned short  battery_status = 0xff;
1645	unsigned short  battery_flag   = 0xff;
1646	int		percentage     = -1;
1647	int             time_units     = -1;
1648	char            *units         = "?";
1649
1650	if ((num_online_cpus() == 1) &&
1651	    !(error = apm_get_power_status(&bx, &cx, &dx))) {
1652		ac_line_status = (bx >> 8) & 0xff;
1653		battery_status = bx & 0xff;
1654		if ((cx & 0xff) != 0xff)
1655			percentage = cx & 0xff;
1656
1657		if (apm_info.connection_version > 0x100) {
1658			battery_flag = (cx >> 8) & 0xff;
1659			if (dx != 0xffff) {
1660				units = (dx & 0x8000) ? "min" : "sec";
1661				time_units = dx & 0x7fff;
1662			}
1663		}
1664	}
1665	/* Arguments, with symbols from linux/apm_bios.h.  Information is
1666	   from the Get Power Status (0x0a) call unless otherwise noted.
1667
1668	   0) Linux driver version (this will change if format changes)
1669	   1) APM BIOS Version.  Usually 1.0, 1.1 or 1.2.
1670	   2) APM flags from APM Installation Check (0x00):
1671	      bit 0: APM_16_BIT_SUPPORT
1672	      bit 1: APM_32_BIT_SUPPORT
1673	      bit 2: APM_IDLE_SLOWS_CLOCK
1674	      bit 3: APM_BIOS_DISABLED
1675	      bit 4: APM_BIOS_DISENGAGED
1676	   3) AC line status
1677	      0x00: Off-line
1678	      0x01: On-line
1679	      0x02: On backup power (BIOS >= 1.1 only)
1680	      0xff: Unknown
1681	   4) Battery status
1682	      0x00: High
1683	      0x01: Low
1684	      0x02: Critical
1685	      0x03: Charging
1686	      0x04: Selected battery not present (BIOS >= 1.2 only)
1687	      0xff: Unknown
1688	   5) Battery flag
1689	      bit 0: High
1690	      bit 1: Low
1691	      bit 2: Critical
1692	      bit 3: Charging
1693	      bit 7: No system battery
1694	      0xff: Unknown
1695	   6) Remaining battery life (percentage of charge):
1696	      0-100: valid
1697	      -1: Unknown
1698	   7) Remaining battery life (time units):
1699	      Number of remaining minutes or seconds
1700	      -1: Unknown
1701	   8) min = minutes; sec = seconds */
1702
1703	seq_printf(m, "%s %d.%d 0x%02x 0x%02x 0x%02x 0x%02x %d%% %d %s\n",
1704		   driver_version,
1705		   (apm_info.bios.version >> 8) & 0xff,
1706		   apm_info.bios.version & 0xff,
1707		   apm_info.bios.flags,
1708		   ac_line_status,
1709		   battery_status,
1710		   battery_flag,
1711		   percentage,
1712		   time_units,
1713		   units);
1714	return 0;
1715}
1716
1717static int proc_apm_open(struct inode *inode, struct file *file)
1718{
1719	return single_open(file, proc_apm_show, NULL);
1720}
1721
1722static const struct file_operations apm_file_ops = {
1723	.owner		= THIS_MODULE,
1724	.open		= proc_apm_open,
1725	.read		= seq_read,
1726	.llseek		= seq_lseek,
1727	.release	= single_release,
1728};
1729
1730static int apm(void *unused)
1731{
1732	unsigned short	bx;
1733	unsigned short	cx;
1734	unsigned short	dx;
1735	int		error;
1736	char 		*power_stat;
1737	char 		*bat_stat;
1738
1739	/* 2002/08/01 - WT
1740	 * This is to avoid random crashes at boot time during initialization
1741	 * on SMP systems in case of "apm=power-off" mode. Seen on ASUS A7M266D.
1742	 * Some bioses don't like being called from CPU != 0.
1743	 * Method suggested by Ingo Molnar.
1744	 */
1745	set_cpus_allowed_ptr(current, cpumask_of(0));
1746	BUG_ON(smp_processor_id() != 0);
1747
1748	if (apm_info.connection_version == 0) {
1749		apm_info.connection_version = apm_info.bios.version;
1750		if (apm_info.connection_version > 0x100) {
1751			/*
1752			 * We only support BIOSs up to version 1.2
1753			 */
1754			if (apm_info.connection_version > 0x0102)
1755				apm_info.connection_version = 0x0102;
1756			error = apm_driver_version(&apm_info.connection_version);
1757			if (error != APM_SUCCESS) {
1758				apm_error("driver version", error);
1759				/* Fall back to an APM 1.0 connection. */
1760				apm_info.connection_version = 0x100;
1761			}
1762		}
1763	}
1764
1765	if (debug)
1766		printk(KERN_INFO "apm: Connection version %d.%d\n",
1767			(apm_info.connection_version >> 8) & 0xff,
1768			apm_info.connection_version & 0xff);
1769
1770#ifdef CONFIG_APM_DO_ENABLE
1771	if (apm_info.bios.flags & APM_BIOS_DISABLED) {
1772		/*
1773		 * This call causes my NEC UltraLite Versa 33/C to hang if it
1774		 * is booted with PM disabled but not in the docking station.
1775		 * Unfortunate ...
1776		 */
1777		error = apm_enable_power_management(1);
1778		if (error) {
1779			apm_error("enable power management", error);
1780			return -1;
1781		}
1782	}
1783#endif
1784
1785	if ((apm_info.bios.flags & APM_BIOS_DISENGAGED)
1786	    && (apm_info.connection_version > 0x0100)) {
1787		error = apm_engage_power_management(APM_DEVICE_ALL, 1);
1788		if (error) {
1789			apm_error("engage power management", error);
1790			return -1;
1791		}
1792	}
1793
1794	if (debug && (num_online_cpus() == 1 || smp)) {
1795		error = apm_get_power_status(&bx, &cx, &dx);
1796		if (error)
1797			printk(KERN_INFO "apm: power status not available\n");
1798		else {
1799			switch ((bx >> 8) & 0xff) {
1800			case 0:
1801				power_stat = "off line";
1802				break;
1803			case 1:
1804				power_stat = "on line";
1805				break;
1806			case 2:
1807				power_stat = "on backup power";
1808				break;
1809			default:
1810				power_stat = "unknown";
1811				break;
1812			}
1813			switch (bx & 0xff) {
1814			case 0:
1815				bat_stat = "high";
1816				break;
1817			case 1:
1818				bat_stat = "low";
1819				break;
1820			case 2:
1821				bat_stat = "critical";
1822				break;
1823			case 3:
1824				bat_stat = "charging";
1825				break;
1826			default:
1827				bat_stat = "unknown";
1828				break;
1829			}
1830			printk(KERN_INFO
1831			       "apm: AC %s, battery status %s, battery life ",
1832			       power_stat, bat_stat);
1833			if ((cx & 0xff) == 0xff)
1834				printk("unknown\n");
1835			else
1836				printk("%d%%\n", cx & 0xff);
1837			if (apm_info.connection_version > 0x100) {
1838				printk(KERN_INFO
1839				       "apm: battery flag 0x%02x, battery life ",
1840				       (cx >> 8) & 0xff);
1841				if (dx == 0xffff)
1842					printk("unknown\n");
1843				else
1844					printk("%d %s\n", dx & 0x7fff,
1845					       (dx & 0x8000) ?
1846					       "minutes" : "seconds");
1847			}
1848		}
1849	}
1850
1851	/* Install our power off handler.. */
1852	if (power_off)
1853		pm_power_off = apm_power_off;
1854
1855	if (num_online_cpus() == 1 || smp) {
1856#if defined(CONFIG_APM_DISPLAY_BLANK) && defined(CONFIG_VT)
1857		console_blank_hook = apm_console_blank;
1858#endif
1859		apm_mainloop();
1860#if defined(CONFIG_APM_DISPLAY_BLANK) && defined(CONFIG_VT)
1861		console_blank_hook = NULL;
1862#endif
1863	}
1864
1865	return 0;
1866}
1867
1868#ifndef MODULE
1869static int __init apm_setup(char *str)
1870{
1871	int invert;
1872
1873	while ((str != NULL) && (*str != '\0')) {
1874		if (strncmp(str, "off", 3) == 0)
1875			apm_disabled = 1;
1876		if (strncmp(str, "on", 2) == 0)
1877			apm_disabled = 0;
1878		if ((strncmp(str, "bounce-interval=", 16) == 0) ||
1879		    (strncmp(str, "bounce_interval=", 16) == 0))
1880			bounce_interval = simple_strtol(str + 16, NULL, 0);
1881		if ((strncmp(str, "idle-threshold=", 15) == 0) ||
1882		    (strncmp(str, "idle_threshold=", 15) == 0))
1883			idle_threshold = simple_strtol(str + 15, NULL, 0);
1884		if ((strncmp(str, "idle-period=", 12) == 0) ||
1885		    (strncmp(str, "idle_period=", 12) == 0))
1886			idle_period = simple_strtol(str + 12, NULL, 0);
1887		invert = (strncmp(str, "no-", 3) == 0) ||
1888			(strncmp(str, "no_", 3) == 0);
1889		if (invert)
1890			str += 3;
1891		if (strncmp(str, "debug", 5) == 0)
1892			debug = !invert;
1893		if ((strncmp(str, "power-off", 9) == 0) ||
1894		    (strncmp(str, "power_off", 9) == 0))
1895			power_off = !invert;
1896		if (strncmp(str, "smp", 3) == 0) {
1897			smp = !invert;
1898			idle_threshold = 100;
1899		}
1900		if ((strncmp(str, "allow-ints", 10) == 0) ||
1901		    (strncmp(str, "allow_ints", 10) == 0))
1902			apm_info.allow_ints = !invert;
1903		if ((strncmp(str, "broken-psr", 10) == 0) ||
1904		    (strncmp(str, "broken_psr", 10) == 0))
1905			apm_info.get_power_status_broken = !invert;
1906		if ((strncmp(str, "realmode-power-off", 18) == 0) ||
1907		    (strncmp(str, "realmode_power_off", 18) == 0))
1908			apm_info.realmode_power_off = !invert;
1909		str = strchr(str, ',');
1910		if (str != NULL)
1911			str += strspn(str, ", \t");
1912	}
1913	return 1;
1914}
1915
1916__setup("apm=", apm_setup);
1917#endif
1918
1919static const struct file_operations apm_bios_fops = {
1920	.owner		= THIS_MODULE,
1921	.read		= do_read,
1922	.poll		= do_poll,
1923	.unlocked_ioctl	= do_ioctl,
1924	.open		= do_open,
1925	.release	= do_release,
1926	.llseek		= noop_llseek,
1927};
1928
1929static struct miscdevice apm_device = {
1930	APM_MINOR_DEV,
1931	"apm_bios",
1932	&apm_bios_fops
1933};
1934
1935
1936/* Simple "print if true" callback */
1937static int __init print_if_true(const struct dmi_system_id *d)
1938{
1939	printk("%s\n", d->ident);
1940	return 0;
1941}
1942
1943/*
1944 * Some Bioses enable the PS/2 mouse (touchpad) at resume, even if it was
1945 * disabled before the suspend. Linux used to get terribly confused by that.
1946 */
1947static int __init broken_ps2_resume(const struct dmi_system_id *d)
1948{
1949	printk(KERN_INFO "%s machine detected. Mousepad Resume Bug "
1950	       "workaround hopefully not needed.\n", d->ident);
1951	return 0;
1952}
1953
1954/* Some bioses have a broken protected mode poweroff and need to use realmode */
1955static int __init set_realmode_power_off(const struct dmi_system_id *d)
1956{
1957	if (apm_info.realmode_power_off == 0) {
1958		apm_info.realmode_power_off = 1;
1959		printk(KERN_INFO "%s bios detected. "
1960		       "Using realmode poweroff only.\n", d->ident);
1961	}
1962	return 0;
1963}
1964
1965/* Some laptops require interrupts to be enabled during APM calls */
1966static int __init set_apm_ints(const struct dmi_system_id *d)
1967{
1968	if (apm_info.allow_ints == 0) {
1969		apm_info.allow_ints = 1;
1970		printk(KERN_INFO "%s machine detected. "
1971		       "Enabling interrupts during APM calls.\n", d->ident);
1972	}
1973	return 0;
1974}
1975
1976/* Some APM bioses corrupt memory or just plain do not work */
1977static int __init apm_is_horked(const struct dmi_system_id *d)
1978{
1979	if (apm_info.disabled == 0) {
1980		apm_info.disabled = 1;
1981		printk(KERN_INFO "%s machine detected. "
1982		       "Disabling APM.\n", d->ident);
1983	}
1984	return 0;
1985}
1986
1987static int __init apm_is_horked_d850md(const struct dmi_system_id *d)
1988{
1989	if (apm_info.disabled == 0) {
1990		apm_info.disabled = 1;
1991		printk(KERN_INFO "%s machine detected. "
1992		       "Disabling APM.\n", d->ident);
1993		printk(KERN_INFO "This bug is fixed in bios P15 which is available for\n");
1994		printk(KERN_INFO "download from support.intel.com\n");
1995	}
1996	return 0;
1997}
1998
1999/* Some APM bioses hang on APM idle calls */
2000static int __init apm_likes_to_melt(const struct dmi_system_id *d)
2001{
2002	if (apm_info.forbid_idle == 0) {
2003		apm_info.forbid_idle = 1;
2004		printk(KERN_INFO "%s machine detected. "
2005		       "Disabling APM idle calls.\n", d->ident);
2006	}
2007	return 0;
2008}
2009
2010/*
2011 *  Check for clue free BIOS implementations who use
2012 *  the following QA technique
2013 *
2014 *      [ Write BIOS Code ]<------
2015 *               |                ^
2016 *      < Does it Compile >----N--
2017 *               |Y               ^
2018 *	< Does it Boot Win98 >-N--
2019 *               |Y
2020 *           [Ship It]
2021 *
2022 *	Phoenix A04  08/24/2000 is known bad (Dell Inspiron 5000e)
2023 *	Phoenix A07  09/29/2000 is known good (Dell Inspiron 5000)
2024 */
2025static int __init broken_apm_power(const struct dmi_system_id *d)
2026{
2027	apm_info.get_power_status_broken = 1;
2028	printk(KERN_WARNING "BIOS strings suggest APM bugs, "
2029	       "disabling power status reporting.\n");
2030	return 0;
2031}
2032
2033/*
2034 * This bios swaps the APM minute reporting bytes over (Many sony laptops
2035 * have this problem).
2036 */
2037static int __init swab_apm_power_in_minutes(const struct dmi_system_id *d)
2038{
2039	apm_info.get_power_status_swabinminutes = 1;
2040	printk(KERN_WARNING "BIOS strings suggest APM reports battery life "
2041	       "in minutes and wrong byte order.\n");
2042	return 0;
2043}
2044
2045static struct dmi_system_id __initdata apm_dmi_table[] = {
2046	{
2047		print_if_true,
2048		KERN_WARNING "IBM T23 - BIOS 1.03b+ and controller firmware 1.02+ may be needed for Linux APM.",
2049		{	DMI_MATCH(DMI_SYS_VENDOR, "IBM"),
2050			DMI_MATCH(DMI_BIOS_VERSION, "1AET38WW (1.01b)"), },
2051	},
2052	{	/* Handle problems with APM on the C600 */
2053		broken_ps2_resume, "Dell Latitude C600",
2054		{	DMI_MATCH(DMI_SYS_VENDOR, "Dell"),
2055			DMI_MATCH(DMI_PRODUCT_NAME, "Latitude C600"), },
2056	},
2057	{	/* Allow interrupts during suspend on Dell Latitude laptops*/
2058		set_apm_ints, "Dell Latitude",
2059		{	DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
2060			DMI_MATCH(DMI_PRODUCT_NAME, "Latitude C510"), }
2061	},
2062	{	/* APM crashes */
2063		apm_is_horked, "Dell Inspiron 2500",
2064		{	DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
2065			DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 2500"),
2066			DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2067			DMI_MATCH(DMI_BIOS_VERSION, "A11"), },
2068	},
2069	{	/* Allow interrupts during suspend on Dell Inspiron laptops*/
2070		set_apm_ints, "Dell Inspiron", {
2071			DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
2072			DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 4000"), },
2073	},
2074	{	/* Handle problems with APM on Inspiron 5000e */
2075		broken_apm_power, "Dell Inspiron 5000e",
2076		{	DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2077			DMI_MATCH(DMI_BIOS_VERSION, "A04"),
2078			DMI_MATCH(DMI_BIOS_DATE, "08/24/2000"), },
2079	},
2080	{	/* Handle problems with APM on Inspiron 2500 */
2081		broken_apm_power, "Dell Inspiron 2500",
2082		{	DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2083			DMI_MATCH(DMI_BIOS_VERSION, "A12"),
2084			DMI_MATCH(DMI_BIOS_DATE, "02/04/2002"), },
2085	},
2086	{	/* APM crashes */
2087		apm_is_horked, "Dell Dimension 4100",
2088		{	DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
2089			DMI_MATCH(DMI_PRODUCT_NAME, "XPS-Z"),
2090			DMI_MATCH(DMI_BIOS_VENDOR, "Intel Corp."),
2091			DMI_MATCH(DMI_BIOS_VERSION, "A11"), },
2092	},
2093	{	/* Allow interrupts during suspend on Compaq Laptops*/
2094		set_apm_ints, "Compaq 12XL125",
2095		{	DMI_MATCH(DMI_SYS_VENDOR, "Compaq"),
2096			DMI_MATCH(DMI_PRODUCT_NAME, "Compaq PC"),
2097			DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2098			DMI_MATCH(DMI_BIOS_VERSION, "4.06"), },
2099	},
2100	{	/* Allow interrupts during APM or the clock goes slow */
2101		set_apm_ints, "ASUSTeK",
2102		{	DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK Computer Inc."),
2103			DMI_MATCH(DMI_PRODUCT_NAME, "L8400K series Notebook PC"), },
2104	},
2105	{	/* APM blows on shutdown */
2106		apm_is_horked, "ABIT KX7-333[R]",
2107		{	DMI_MATCH(DMI_BOARD_VENDOR, "ABIT"),
2108			DMI_MATCH(DMI_BOARD_NAME, "VT8367-8233A (KX7-333[R])"), },
2109	},
2110	{	/* APM crashes */
2111		apm_is_horked, "Trigem Delhi3",
2112		{	DMI_MATCH(DMI_SYS_VENDOR, "TriGem Computer, Inc"),
2113			DMI_MATCH(DMI_PRODUCT_NAME, "Delhi3"), },
2114	},
2115	{	/* APM crashes */
2116		apm_is_horked, "Fujitsu-Siemens",
2117		{	DMI_MATCH(DMI_BIOS_VENDOR, "hoenix/FUJITSU SIEMENS"),
2118			DMI_MATCH(DMI_BIOS_VERSION, "Version1.01"), },
2119	},
2120	{	/* APM crashes */
2121		apm_is_horked_d850md, "Intel D850MD",
2122		{	DMI_MATCH(DMI_BIOS_VENDOR, "Intel Corp."),
2123			DMI_MATCH(DMI_BIOS_VERSION, "MV85010A.86A.0016.P07.0201251536"), },
2124	},
2125	{	/* APM crashes */
2126		apm_is_horked, "Intel D810EMO",
2127		{	DMI_MATCH(DMI_BIOS_VENDOR, "Intel Corp."),
2128			DMI_MATCH(DMI_BIOS_VERSION, "MO81010A.86A.0008.P04.0004170800"), },
2129	},
2130	{	/* APM crashes */
2131		apm_is_horked, "Dell XPS-Z",
2132		{	DMI_MATCH(DMI_BIOS_VENDOR, "Intel Corp."),
2133			DMI_MATCH(DMI_BIOS_VERSION, "A11"),
2134			DMI_MATCH(DMI_PRODUCT_NAME, "XPS-Z"), },
2135	},
2136	{	/* APM crashes */
2137		apm_is_horked, "Sharp PC-PJ/AX",
2138		{	DMI_MATCH(DMI_SYS_VENDOR, "SHARP"),
2139			DMI_MATCH(DMI_PRODUCT_NAME, "PC-PJ/AX"),
2140			DMI_MATCH(DMI_BIOS_VENDOR, "SystemSoft"),
2141			DMI_MATCH(DMI_BIOS_VERSION, "Version R2.08"), },
2142	},
2143	{	/* APM crashes */
2144		apm_is_horked, "Dell Inspiron 2500",
2145		{	DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
2146			DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 2500"),
2147			DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2148			DMI_MATCH(DMI_BIOS_VERSION, "A11"), },
2149	},
2150	{	/* APM idle hangs */
2151		apm_likes_to_melt, "Jabil AMD",
2152		{	DMI_MATCH(DMI_BIOS_VENDOR, "American Megatrends Inc."),
2153			DMI_MATCH(DMI_BIOS_VERSION, "0AASNP06"), },
2154	},
2155	{	/* APM idle hangs */
2156		apm_likes_to_melt, "AMI Bios",
2157		{	DMI_MATCH(DMI_BIOS_VENDOR, "American Megatrends Inc."),
2158			DMI_MATCH(DMI_BIOS_VERSION, "0AASNP05"), },
2159	},
2160	{	/* Handle problems with APM on Sony Vaio PCG-N505X(DE) */
2161		swab_apm_power_in_minutes, "Sony VAIO",
2162		{	DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2163			DMI_MATCH(DMI_BIOS_VERSION, "R0206H"),
2164			DMI_MATCH(DMI_BIOS_DATE, "08/23/99"), },
2165	},
2166	{	/* Handle problems with APM on Sony Vaio PCG-N505VX */
2167		swab_apm_power_in_minutes, "Sony VAIO",
2168		{	DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2169			DMI_MATCH(DMI_BIOS_VERSION, "W2K06H0"),
2170			DMI_MATCH(DMI_BIOS_DATE, "02/03/00"), },
2171	},
2172	{	/* Handle problems with APM on Sony Vaio PCG-XG29 */
2173		swab_apm_power_in_minutes, "Sony VAIO",
2174		{	DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2175			DMI_MATCH(DMI_BIOS_VERSION, "R0117A0"),
2176			DMI_MATCH(DMI_BIOS_DATE, "04/25/00"), },
2177	},
2178	{	/* Handle problems with APM on Sony Vaio PCG-Z600NE */
2179		swab_apm_power_in_minutes, "Sony VAIO",
2180		{	DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2181			DMI_MATCH(DMI_BIOS_VERSION, "R0121Z1"),
2182			DMI_MATCH(DMI_BIOS_DATE, "05/11/00"), },
2183	},
2184	{	/* Handle problems with APM on Sony Vaio PCG-Z600NE */
2185		swab_apm_power_in_minutes, "Sony VAIO",
2186		{	DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2187			DMI_MATCH(DMI_BIOS_VERSION, "WME01Z1"),
2188			DMI_MATCH(DMI_BIOS_DATE, "08/11/00"), },
2189	},
2190	{	/* Handle problems with APM on Sony Vaio PCG-Z600LEK(DE) */
2191		swab_apm_power_in_minutes, "Sony VAIO",
2192		{	DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2193			DMI_MATCH(DMI_BIOS_VERSION, "R0206Z3"),
2194			DMI_MATCH(DMI_BIOS_DATE, "12/25/00"), },
2195	},
2196	{	/* Handle problems with APM on Sony Vaio PCG-Z505LS */
2197		swab_apm_power_in_minutes, "Sony VAIO",
2198		{	DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2199			DMI_MATCH(DMI_BIOS_VERSION, "R0203D0"),
2200			DMI_MATCH(DMI_BIOS_DATE, "05/12/00"), },
2201	},
2202	{	/* Handle problems with APM on Sony Vaio PCG-Z505LS */
2203		swab_apm_power_in_minutes, "Sony VAIO",
2204		{	DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2205			DMI_MATCH(DMI_BIOS_VERSION, "R0203Z3"),
2206			DMI_MATCH(DMI_BIOS_DATE, "08/25/00"), },
2207	},
2208	{	/* Handle problems with APM on Sony Vaio PCG-Z505LS (with updated BIOS) */
2209		swab_apm_power_in_minutes, "Sony VAIO",
2210		{	DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2211			DMI_MATCH(DMI_BIOS_VERSION, "R0209Z3"),
2212			DMI_MATCH(DMI_BIOS_DATE, "05/12/01"), },
2213	},
2214	{	/* Handle problems with APM on Sony Vaio PCG-F104K */
2215		swab_apm_power_in_minutes, "Sony VAIO",
2216		{	DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2217			DMI_MATCH(DMI_BIOS_VERSION, "R0204K2"),
2218			DMI_MATCH(DMI_BIOS_DATE, "08/28/00"), },
2219	},
2220
2221	{	/* Handle problems with APM on Sony Vaio PCG-C1VN/C1VE */
2222		swab_apm_power_in_minutes, "Sony VAIO",
2223		{	DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2224			DMI_MATCH(DMI_BIOS_VERSION, "R0208P1"),
2225			DMI_MATCH(DMI_BIOS_DATE, "11/09/00"), },
2226	},
2227	{	/* Handle problems with APM on Sony Vaio PCG-C1VE */
2228		swab_apm_power_in_minutes, "Sony VAIO",
2229		{	DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2230			DMI_MATCH(DMI_BIOS_VERSION, "R0204P1"),
2231			DMI_MATCH(DMI_BIOS_DATE, "09/12/00"), },
2232	},
2233	{	/* Handle problems with APM on Sony Vaio PCG-C1VE */
2234		swab_apm_power_in_minutes, "Sony VAIO",
2235		{	DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2236			DMI_MATCH(DMI_BIOS_VERSION, "WXPO1Z3"),
2237			DMI_MATCH(DMI_BIOS_DATE, "10/26/01"), },
2238	},
2239	{	/* broken PM poweroff bios */
2240		set_realmode_power_off, "Award Software v4.60 PGMA",
2241		{	DMI_MATCH(DMI_BIOS_VENDOR, "Award Software International, Inc."),
2242			DMI_MATCH(DMI_BIOS_VERSION, "4.60 PGMA"),
2243			DMI_MATCH(DMI_BIOS_DATE, "134526184"), },
2244	},
2245
2246	/* Generic per vendor APM settings  */
2247
2248	{	/* Allow interrupts during suspend on IBM laptops */
2249		set_apm_ints, "IBM",
2250		{	DMI_MATCH(DMI_SYS_VENDOR, "IBM"), },
2251	},
2252
2253	{ }
2254};
2255
2256/*
2257 * Just start the APM thread. We do NOT want to do APM BIOS
2258 * calls from anything but the APM thread, if for no other reason
2259 * than the fact that we don't trust the APM BIOS. This way,
2260 * most common APM BIOS problems that lead to protection errors
2261 * etc will have at least some level of being contained...
2262 *
2263 * In short, if something bad happens, at least we have a choice
2264 * of just killing the apm thread..
2265 */
2266static int __init apm_init(void)
2267{
2268	struct desc_struct *gdt;
2269	int err;
2270
2271	dmi_check_system(apm_dmi_table);
2272
2273	if (apm_info.bios.version == 0 || machine_is_olpc()) {
2274		printk(KERN_INFO "apm: BIOS not found.\n");
2275		return -ENODEV;
2276	}
2277	printk(KERN_INFO
2278	       "apm: BIOS version %d.%d Flags 0x%02x (Driver version %s)\n",
2279	       ((apm_info.bios.version >> 8) & 0xff),
2280	       (apm_info.bios.version & 0xff),
2281	       apm_info.bios.flags,
2282	       driver_version);
2283	if ((apm_info.bios.flags & APM_32_BIT_SUPPORT) == 0) {
2284		printk(KERN_INFO "apm: no 32 bit BIOS support\n");
2285		return -ENODEV;
2286	}
2287
2288	if (allow_ints)
2289		apm_info.allow_ints = 1;
2290	if (broken_psr)
2291		apm_info.get_power_status_broken = 1;
2292	if (realmode_power_off)
2293		apm_info.realmode_power_off = 1;
2294	/* User can override, but default is to trust DMI */
2295	if (apm_disabled != -1)
2296		apm_info.disabled = apm_disabled;
2297
2298	/*
2299	 * Fix for the Compaq Contura 3/25c which reports BIOS version 0.1
2300	 * but is reportedly a 1.0 BIOS.
2301	 */
2302	if (apm_info.bios.version == 0x001)
2303		apm_info.bios.version = 0x100;
2304
2305	/* BIOS < 1.2 doesn't set cseg_16_len */
2306	if (apm_info.bios.version < 0x102)
2307		apm_info.bios.cseg_16_len = 0; /* 64k */
2308
2309	if (debug) {
2310		printk(KERN_INFO "apm: entry %x:%x cseg16 %x dseg %x",
2311			apm_info.bios.cseg, apm_info.bios.offset,
2312			apm_info.bios.cseg_16, apm_info.bios.dseg);
2313		if (apm_info.bios.version > 0x100)
2314			printk(" cseg len %x, dseg len %x",
2315				apm_info.bios.cseg_len,
2316				apm_info.bios.dseg_len);
2317		if (apm_info.bios.version > 0x101)
2318			printk(" cseg16 len %x", apm_info.bios.cseg_16_len);
2319		printk("\n");
2320	}
2321
2322	if (apm_info.disabled) {
2323		pr_notice("disabled on user request.\n");
2324		return -ENODEV;
2325	}
2326	if ((num_online_cpus() > 1) && !power_off && !smp) {
2327		pr_notice("disabled - APM is not SMP safe.\n");
2328		apm_info.disabled = 1;
2329		return -ENODEV;
2330	}
2331	if (!acpi_disabled) {
2332		pr_notice("overridden by ACPI.\n");
2333		apm_info.disabled = 1;
2334		return -ENODEV;
2335	}
2336
2337	/*
2338	 * Set up the long jump entry point to the APM BIOS, which is called
2339	 * from inline assembly.
2340	 */
2341	apm_bios_entry.offset = apm_info.bios.offset;
2342	apm_bios_entry.segment = APM_CS;
2343
2344	/*
2345	 * The APM 1.1 BIOS is supposed to provide limit information that it
2346	 * recognizes.  Many machines do this correctly, but many others do
2347	 * not restrict themselves to their claimed limit.  When this happens,
2348	 * they will cause a segmentation violation in the kernel at boot time.
2349	 * Most BIOS's, however, will respect a 64k limit, so we use that.
2350	 *
2351	 * Note we only set APM segments on CPU zero, since we pin the APM
2352	 * code to that CPU.
2353	 */
2354	gdt = get_cpu_gdt_table(0);
2355	set_desc_base(&gdt[APM_CS >> 3],
2356		 (unsigned long)__va((unsigned long)apm_info.bios.cseg << 4));
2357	set_desc_base(&gdt[APM_CS_16 >> 3],
2358		 (unsigned long)__va((unsigned long)apm_info.bios.cseg_16 << 4));
2359	set_desc_base(&gdt[APM_DS >> 3],
2360		 (unsigned long)__va((unsigned long)apm_info.bios.dseg << 4));
2361
2362	proc_create("apm", 0, NULL, &apm_file_ops);
2363
2364	kapmd_task = kthread_create(apm, NULL, "kapmd");
2365	if (IS_ERR(kapmd_task)) {
2366		pr_err("disabled - Unable to start kernel thread\n");
2367		err = PTR_ERR(kapmd_task);
2368		kapmd_task = NULL;
2369		remove_proc_entry("apm", NULL);
2370		return err;
2371	}
2372	wake_up_process(kapmd_task);
2373
2374	if (num_online_cpus() > 1 && !smp) {
2375		printk(KERN_NOTICE
2376		       "apm: disabled - APM is not SMP safe (power off active).\n");
2377		return 0;
2378	}
2379
2380	/*
2381	 * Note we don't actually care if the misc_device cannot be registered.
2382	 * this driver can do its job without it, even if userspace can't
2383	 * control it.  just log the error
2384	 */
2385	if (misc_register(&apm_device))
2386		printk(KERN_WARNING "apm: Could not register misc device.\n");
2387
2388	if (HZ != 100)
2389		idle_period = (idle_period * HZ) / 100;
2390	if (idle_threshold < 100) {
2391		if (!cpuidle_register_driver(&apm_idle_driver))
2392			if (cpuidle_register_device(&apm_cpuidle_device))
2393				cpuidle_unregister_driver(&apm_idle_driver);
2394	}
2395
2396	return 0;
2397}
2398
2399static void __exit apm_exit(void)
2400{
2401	int error;
2402
2403	cpuidle_unregister_device(&apm_cpuidle_device);
2404	cpuidle_unregister_driver(&apm_idle_driver);
2405
2406	if (((apm_info.bios.flags & APM_BIOS_DISENGAGED) == 0)
2407	    && (apm_info.connection_version > 0x0100)) {
2408		error = apm_engage_power_management(APM_DEVICE_ALL, 0);
2409		if (error)
2410			apm_error("disengage power management", error);
2411	}
2412	misc_deregister(&apm_device);
2413	remove_proc_entry("apm", NULL);
2414	if (power_off)
2415		pm_power_off = NULL;
2416	if (kapmd_task) {
2417		kthread_stop(kapmd_task);
2418		kapmd_task = NULL;
2419	}
2420}
2421
2422module_init(apm_init);
2423module_exit(apm_exit);
2424
2425MODULE_AUTHOR("Stephen Rothwell");
2426MODULE_DESCRIPTION("Advanced Power Management");
2427MODULE_LICENSE("GPL");
2428module_param(debug, bool, 0644);
2429MODULE_PARM_DESC(debug, "Enable debug mode");
2430module_param(power_off, bool, 0444);
2431MODULE_PARM_DESC(power_off, "Enable power off");
2432module_param(bounce_interval, int, 0444);
2433MODULE_PARM_DESC(bounce_interval,
2434		"Set the number of ticks to ignore suspend bounces");
2435module_param(allow_ints, bool, 0444);
2436MODULE_PARM_DESC(allow_ints, "Allow interrupts during BIOS calls");
2437module_param(broken_psr, bool, 0444);
2438MODULE_PARM_DESC(broken_psr, "BIOS has a broken GetPowerStatus call");
2439module_param(realmode_power_off, bool, 0444);
2440MODULE_PARM_DESC(realmode_power_off,
2441		"Switch to real mode before powering off");
2442module_param(idle_threshold, int, 0444);
2443MODULE_PARM_DESC(idle_threshold,
2444	"System idle percentage above which to make APM BIOS idle calls");
2445module_param(idle_period, int, 0444);
2446MODULE_PARM_DESC(idle_period,
2447	"Period (in sec/100) over which to caculate the idle percentage");
2448module_param(smp, bool, 0444);
2449MODULE_PARM_DESC(smp,
2450	"Set this to enable APM use on an SMP platform. Use with caution on older systems");
2451MODULE_ALIAS_MISCDEV(APM_MINOR_DEV);
v3.15
   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			.flags = CPUIDLE_FLAG_TIME_VALID,
 382			.exit_latency = 250,	/* WAG */
 383			.target_residency = 500,	/* WAG */
 384			.enter = &apm_cpu_idle
 385		},
 386	},
 387	.state_count = 2,
 388};
 389
 390static struct cpuidle_device apm_cpuidle_device;
 391
 392/*
 393 * Local variables
 394 */
 395__visible struct {
 396	unsigned long	offset;
 397	unsigned short	segment;
 398} apm_bios_entry;
 399static int clock_slowed;
 400static int idle_threshold __read_mostly = DEFAULT_IDLE_THRESHOLD;
 401static int idle_period __read_mostly = DEFAULT_IDLE_PERIOD;
 402static int suspends_pending;
 403static int standbys_pending;
 404static int ignore_sys_suspend;
 405static int ignore_normal_resume;
 406static int bounce_interval __read_mostly = DEFAULT_BOUNCE_INTERVAL;
 407
 408static bool debug __read_mostly;
 409static bool smp __read_mostly;
 410static int apm_disabled = -1;
 411#ifdef CONFIG_SMP
 412static bool power_off;
 413#else
 414static bool power_off = 1;
 415#endif
 416static bool realmode_power_off;
 417#ifdef CONFIG_APM_ALLOW_INTS
 418static bool allow_ints = 1;
 419#else
 420static bool allow_ints;
 421#endif
 422static bool broken_psr;
 423
 424static DECLARE_WAIT_QUEUE_HEAD(apm_waitqueue);
 425static DECLARE_WAIT_QUEUE_HEAD(apm_suspend_waitqueue);
 426static struct apm_user *user_list;
 427static DEFINE_SPINLOCK(user_list_lock);
 428static DEFINE_MUTEX(apm_mutex);
 429
 430/*
 431 * Set up a segment that references the real mode segment 0x40
 432 * that extends up to the end of page zero (that we have reserved).
 433 * This is for buggy BIOS's that refer to (real mode) segment 0x40
 434 * even though they are called in protected mode.
 435 */
 436static struct desc_struct bad_bios_desc = GDT_ENTRY_INIT(0x4092,
 437			(unsigned long)__va(0x400UL), PAGE_SIZE - 0x400 - 1);
 438
 439static const char driver_version[] = "1.16ac";	/* no spaces */
 440
 441static struct task_struct *kapmd_task;
 442
 443/*
 444 *	APM event names taken from the APM 1.2 specification. These are
 445 *	the message codes that the BIOS uses to tell us about events
 446 */
 447static const char * const apm_event_name[] = {
 448	"system standby",
 449	"system suspend",
 450	"normal resume",
 451	"critical resume",
 452	"low battery",
 453	"power status change",
 454	"update time",
 455	"critical suspend",
 456	"user standby",
 457	"user suspend",
 458	"system standby resume",
 459	"capabilities change"
 460};
 461#define NR_APM_EVENT_NAME ARRAY_SIZE(apm_event_name)
 462
 463typedef struct lookup_t {
 464	int	key;
 465	char 	*msg;
 466} lookup_t;
 467
 468/*
 469 *	The BIOS returns a set of standard error codes in AX when the
 470 *	carry flag is set.
 471 */
 472
 473static const lookup_t error_table[] = {
 474/* N/A	{ APM_SUCCESS,		"Operation succeeded" }, */
 475	{ APM_DISABLED,		"Power management disabled" },
 476	{ APM_CONNECTED,	"Real mode interface already connected" },
 477	{ APM_NOT_CONNECTED,	"Interface not connected" },
 478	{ APM_16_CONNECTED,	"16 bit interface already connected" },
 479/* N/A	{ APM_16_UNSUPPORTED,	"16 bit interface not supported" }, */
 480	{ APM_32_CONNECTED,	"32 bit interface already connected" },
 481	{ APM_32_UNSUPPORTED,	"32 bit interface not supported" },
 482	{ APM_BAD_DEVICE,	"Unrecognized device ID" },
 483	{ APM_BAD_PARAM,	"Parameter out of range" },
 484	{ APM_NOT_ENGAGED,	"Interface not engaged" },
 485	{ APM_BAD_FUNCTION,     "Function not supported" },
 486	{ APM_RESUME_DISABLED,	"Resume timer disabled" },
 487	{ APM_BAD_STATE,	"Unable to enter requested state" },
 488/* N/A	{ APM_NO_EVENTS,	"No events pending" }, */
 489	{ APM_NO_ERROR,		"BIOS did not set a return code" },
 490	{ APM_NOT_PRESENT,	"No APM present" }
 491};
 492#define ERROR_COUNT	ARRAY_SIZE(error_table)
 493
 494/**
 495 *	apm_error	-	display an APM error
 496 *	@str: information string
 497 *	@err: APM BIOS return code
 498 *
 499 *	Write a meaningful log entry to the kernel log in the event of
 500 *	an APM error.  Note that this also handles (negative) kernel errors.
 501 */
 502
 503static void apm_error(char *str, int err)
 504{
 505	int i;
 506
 507	for (i = 0; i < ERROR_COUNT; i++)
 508		if (error_table[i].key == err)
 509			break;
 510	if (i < ERROR_COUNT)
 511		pr_notice("%s: %s\n", str, error_table[i].msg);
 512	else if (err < 0)
 513		pr_notice("%s: linux error code %i\n", str, err);
 514	else
 515		pr_notice("%s: unknown error code %#2.2x\n",
 516		       str, err);
 517}
 518
 519/*
 520 * These are the actual BIOS calls.  Depending on APM_ZERO_SEGS and
 521 * apm_info.allow_ints, we are being really paranoid here!  Not only
 522 * are interrupts disabled, but all the segment registers (except SS)
 523 * are saved and zeroed this means that if the BIOS tries to reference
 524 * any data without explicitly loading the segment registers, the kernel
 525 * will fault immediately rather than have some unforeseen circumstances
 526 * for the rest of the kernel.  And it will be very obvious!  :-) Doing
 527 * this depends on CS referring to the same physical memory as DS so that
 528 * DS can be zeroed before the call. Unfortunately, we can't do anything
 529 * about the stack segment/pointer.  Also, we tell the compiler that
 530 * everything could change.
 531 *
 532 * Also, we KNOW that for the non error case of apm_bios_call, there
 533 * is no useful data returned in the low order 8 bits of eax.
 534 */
 535
 536static inline unsigned long __apm_irq_save(void)
 537{
 538	unsigned long flags;
 539	local_save_flags(flags);
 540	if (apm_info.allow_ints) {
 541		if (irqs_disabled_flags(flags))
 542			local_irq_enable();
 543	} else
 544		local_irq_disable();
 545
 546	return flags;
 547}
 548
 549#define apm_irq_save(flags) \
 550	do { flags = __apm_irq_save(); } while (0)
 551
 552static inline void apm_irq_restore(unsigned long flags)
 553{
 554	if (irqs_disabled_flags(flags))
 555		local_irq_disable();
 556	else if (irqs_disabled())
 557		local_irq_enable();
 558}
 559
 560#ifdef APM_ZERO_SEGS
 561#	define APM_DECL_SEGS \
 562		unsigned int saved_fs; unsigned int saved_gs;
 563#	define APM_DO_SAVE_SEGS \
 564		savesegment(fs, saved_fs); savesegment(gs, saved_gs)
 565#	define APM_DO_RESTORE_SEGS \
 566		loadsegment(fs, saved_fs); loadsegment(gs, saved_gs)
 567#else
 568#	define APM_DECL_SEGS
 569#	define APM_DO_SAVE_SEGS
 570#	define APM_DO_RESTORE_SEGS
 571#endif
 572
 573struct apm_bios_call {
 574	u32 func;
 575	/* In and out */
 576	u32 ebx;
 577	u32 ecx;
 578	/* Out only */
 579	u32 eax;
 580	u32 edx;
 581	u32 esi;
 582
 583	/* Error: -ENOMEM, or bits 8-15 of eax */
 584	int err;
 585};
 586
 587/**
 588 *	__apm_bios_call - Make an APM BIOS 32bit call
 589 *	@_call: pointer to struct apm_bios_call.
 590 *
 591 *	Make an APM call using the 32bit protected mode interface. The
 592 *	caller is responsible for knowing if APM BIOS is configured and
 593 *	enabled. This call can disable interrupts for a long period of
 594 *	time on some laptops.  The return value is in AH and the carry
 595 *	flag is loaded into AL.  If there is an error, then the error
 596 *	code is returned in AH (bits 8-15 of eax) and this function
 597 *	returns non-zero.
 598 *
 599 *	Note: this makes the call on the current CPU.
 600 */
 601static long __apm_bios_call(void *_call)
 602{
 603	APM_DECL_SEGS
 604	unsigned long		flags;
 605	int			cpu;
 606	struct desc_struct	save_desc_40;
 607	struct desc_struct	*gdt;
 608	struct apm_bios_call	*call = _call;
 609
 610	cpu = get_cpu();
 611	BUG_ON(cpu != 0);
 612	gdt = get_cpu_gdt_table(cpu);
 613	save_desc_40 = gdt[0x40 / 8];
 614	gdt[0x40 / 8] = bad_bios_desc;
 615
 616	apm_irq_save(flags);
 617	APM_DO_SAVE_SEGS;
 618	apm_bios_call_asm(call->func, call->ebx, call->ecx,
 619			  &call->eax, &call->ebx, &call->ecx, &call->edx,
 620			  &call->esi);
 621	APM_DO_RESTORE_SEGS;
 622	apm_irq_restore(flags);
 623	gdt[0x40 / 8] = save_desc_40;
 624	put_cpu();
 625
 626	return call->eax & 0xff;
 627}
 628
 629/* Run __apm_bios_call or __apm_bios_call_simple on CPU 0 */
 630static int on_cpu0(long (*fn)(void *), struct apm_bios_call *call)
 631{
 632	int ret;
 633
 634	/* Don't bother with work_on_cpu in the common case, so we don't
 635	 * have to worry about OOM or overhead. */
 636	if (get_cpu() == 0) {
 637		ret = fn(call);
 638		put_cpu();
 639	} else {
 640		put_cpu();
 641		ret = work_on_cpu(0, fn, call);
 642	}
 643
 644	/* work_on_cpu can fail with -ENOMEM */
 645	if (ret < 0)
 646		call->err = ret;
 647	else
 648		call->err = (call->eax >> 8) & 0xff;
 649
 650	return ret;
 651}
 652
 653/**
 654 *	apm_bios_call	-	Make an APM BIOS 32bit call (on CPU 0)
 655 *	@call: the apm_bios_call registers.
 656 *
 657 *	If there is an error, it is returned in @call.err.
 658 */
 659static int apm_bios_call(struct apm_bios_call *call)
 660{
 661	return on_cpu0(__apm_bios_call, call);
 662}
 663
 664/**
 665 *	__apm_bios_call_simple - Make an APM BIOS 32bit call (on CPU 0)
 666 *	@_call: pointer to struct apm_bios_call.
 667 *
 668 *	Make a BIOS call that returns one value only, or just status.
 669 *	If there is an error, then the error code is returned in AH
 670 *	(bits 8-15 of eax) and this function returns non-zero (it can
 671 *	also return -ENOMEM). This is used for simpler BIOS operations.
 672 *	This call may hold interrupts off for a long time on some laptops.
 673 *
 674 *	Note: this makes the call on the current CPU.
 675 */
 676static long __apm_bios_call_simple(void *_call)
 677{
 678	u8			error;
 679	APM_DECL_SEGS
 680	unsigned long		flags;
 681	int			cpu;
 682	struct desc_struct	save_desc_40;
 683	struct desc_struct	*gdt;
 684	struct apm_bios_call	*call = _call;
 685
 686	cpu = get_cpu();
 687	BUG_ON(cpu != 0);
 688	gdt = get_cpu_gdt_table(cpu);
 689	save_desc_40 = gdt[0x40 / 8];
 690	gdt[0x40 / 8] = bad_bios_desc;
 691
 692	apm_irq_save(flags);
 693	APM_DO_SAVE_SEGS;
 694	error = apm_bios_call_simple_asm(call->func, call->ebx, call->ecx,
 695					 &call->eax);
 696	APM_DO_RESTORE_SEGS;
 697	apm_irq_restore(flags);
 698	gdt[0x40 / 8] = save_desc_40;
 699	put_cpu();
 700	return error;
 701}
 702
 703/**
 704 *	apm_bios_call_simple	-	make a simple APM BIOS 32bit call
 705 *	@func: APM function to invoke
 706 *	@ebx_in: EBX register value for BIOS call
 707 *	@ecx_in: ECX register value for BIOS call
 708 *	@eax: EAX register on return from the BIOS call
 709 *	@err: bits
 710 *
 711 *	Make a BIOS call that returns one value only, or just status.
 712 *	If there is an error, then the error code is returned in @err
 713 *	and this function returns non-zero. This is used for simpler
 714 *	BIOS operations.  This call may hold interrupts off for a long
 715 *	time on some laptops.
 716 */
 717static int apm_bios_call_simple(u32 func, u32 ebx_in, u32 ecx_in, u32 *eax,
 718				int *err)
 719{
 720	struct apm_bios_call call;
 721	int ret;
 722
 723	call.func = func;
 724	call.ebx = ebx_in;
 725	call.ecx = ecx_in;
 726
 727	ret = on_cpu0(__apm_bios_call_simple, &call);
 728	*eax = call.eax;
 729	*err = call.err;
 730	return ret;
 731}
 732
 733/**
 734 *	apm_driver_version	-	APM driver version
 735 *	@val:	loaded with the APM version on return
 736 *
 737 *	Retrieve the APM version supported by the BIOS. This is only
 738 *	supported for APM 1.1 or higher. An error indicates APM 1.0 is
 739 *	probably present.
 740 *
 741 *	On entry val should point to a value indicating the APM driver
 742 *	version with the high byte being the major and the low byte the
 743 *	minor number both in BCD
 744 *
 745 *	On return it will hold the BIOS revision supported in the
 746 *	same format.
 747 */
 748
 749static int apm_driver_version(u_short *val)
 750{
 751	u32 eax;
 752	int err;
 753
 754	if (apm_bios_call_simple(APM_FUNC_VERSION, 0, *val, &eax, &err))
 755		return err;
 756	*val = eax;
 757	return APM_SUCCESS;
 758}
 759
 760/**
 761 *	apm_get_event	-	get an APM event from the BIOS
 762 *	@event: pointer to the event
 763 *	@info: point to the event information
 764 *
 765 *	The APM BIOS provides a polled information for event
 766 *	reporting. The BIOS expects to be polled at least every second
 767 *	when events are pending. When a message is found the caller should
 768 *	poll until no more messages are present.  However, this causes
 769 *	problems on some laptops where a suspend event notification is
 770 *	not cleared until it is acknowledged.
 771 *
 772 *	Additional information is returned in the info pointer, providing
 773 *	that APM 1.2 is in use. If no messges are pending the value 0x80
 774 *	is returned (No power management events pending).
 775 */
 776static int apm_get_event(apm_event_t *event, apm_eventinfo_t *info)
 777{
 778	struct apm_bios_call call;
 779
 780	call.func = APM_FUNC_GET_EVENT;
 781	call.ebx = call.ecx = 0;
 782
 783	if (apm_bios_call(&call))
 784		return call.err;
 785
 786	*event = call.ebx;
 787	if (apm_info.connection_version < 0x0102)
 788		*info = ~0; /* indicate info not valid */
 789	else
 790		*info = call.ecx;
 791	return APM_SUCCESS;
 792}
 793
 794/**
 795 *	set_power_state	-	set the power management state
 796 *	@what: which items to transition
 797 *	@state: state to transition to
 798 *
 799 *	Request an APM change of state for one or more system devices. The
 800 *	processor state must be transitioned last of all. what holds the
 801 *	class of device in the upper byte and the device number (0xFF for
 802 *	all) for the object to be transitioned.
 803 *
 804 *	The state holds the state to transition to, which may in fact
 805 *	be an acceptance of a BIOS requested state change.
 806 */
 807
 808static int set_power_state(u_short what, u_short state)
 809{
 810	u32 eax;
 811	int err;
 812
 813	if (apm_bios_call_simple(APM_FUNC_SET_STATE, what, state, &eax, &err))
 814		return err;
 815	return APM_SUCCESS;
 816}
 817
 818/**
 819 *	set_system_power_state - set system wide power state
 820 *	@state: which state to enter
 821 *
 822 *	Transition the entire system into a new APM power state.
 823 */
 824
 825static int set_system_power_state(u_short state)
 826{
 827	return set_power_state(APM_DEVICE_ALL, state);
 828}
 829
 830/**
 831 *	apm_do_idle	-	perform power saving
 832 *
 833 *	This function notifies the BIOS that the processor is (in the view
 834 *	of the OS) idle. It returns -1 in the event that the BIOS refuses
 835 *	to handle the idle request. On a success the function returns 1
 836 *	if the BIOS did clock slowing or 0 otherwise.
 837 */
 838
 839static int apm_do_idle(void)
 840{
 841	u32 eax;
 842	u8 ret = 0;
 843	int idled = 0;
 844	int polling;
 845	int err = 0;
 846
 847	polling = !!(current_thread_info()->status & TS_POLLING);
 848	if (polling) {
 849		current_thread_info()->status &= ~TS_POLLING;
 850		/*
 851		 * TS_POLLING-cleared state must be visible before we
 852		 * test NEED_RESCHED:
 853		 */
 854		smp_mb();
 855	}
 856	if (!need_resched()) {
 857		idled = 1;
 858		ret = apm_bios_call_simple(APM_FUNC_IDLE, 0, 0, &eax, &err);
 859	}
 860	if (polling)
 861		current_thread_info()->status |= TS_POLLING;
 862
 863	if (!idled)
 864		return 0;
 865
 866	if (ret) {
 867		static unsigned long t;
 868
 869		/* This always fails on some SMP boards running UP kernels.
 870		 * Only report the failure the first 5 times.
 871		 */
 872		if (++t < 5) {
 873			printk(KERN_DEBUG "apm_do_idle failed (%d)\n", err);
 874			t = jiffies;
 875		}
 876		return -1;
 877	}
 878	clock_slowed = (apm_info.bios.flags & APM_IDLE_SLOWS_CLOCK) != 0;
 879	return clock_slowed;
 880}
 881
 882/**
 883 *	apm_do_busy	-	inform the BIOS the CPU is busy
 884 *
 885 *	Request that the BIOS brings the CPU back to full performance.
 886 */
 887
 888static void apm_do_busy(void)
 889{
 890	u32 dummy;
 891	int err;
 892
 893	if (clock_slowed || ALWAYS_CALL_BUSY) {
 894		(void)apm_bios_call_simple(APM_FUNC_BUSY, 0, 0, &dummy, &err);
 895		clock_slowed = 0;
 896	}
 897}
 898
 899/*
 900 * If no process has really been interested in
 901 * the CPU for some time, we want to call BIOS
 902 * power management - we probably want
 903 * to conserve power.
 904 */
 905#define IDLE_CALC_LIMIT	(HZ * 100)
 906#define IDLE_LEAKY_MAX	16
 907
 908/**
 909 * apm_cpu_idle		-	cpu idling for APM capable Linux
 910 *
 911 * This is the idling function the kernel executes when APM is available. It
 912 * tries to do BIOS powermanagement based on the average system idle time.
 913 * Furthermore it calls the system default idle routine.
 914 */
 915
 916static int apm_cpu_idle(struct cpuidle_device *dev,
 917	struct cpuidle_driver *drv, int index)
 918{
 919	static int use_apm_idle; /* = 0 */
 920	static unsigned int last_jiffies; /* = 0 */
 921	static unsigned int last_stime; /* = 0 */
 922	cputime_t stime;
 923
 924	int apm_idle_done = 0;
 925	unsigned int jiffies_since_last_check = jiffies - last_jiffies;
 926	unsigned int bucket;
 927
 928recalc:
 929	task_cputime(current, NULL, &stime);
 930	if (jiffies_since_last_check > IDLE_CALC_LIMIT) {
 931		use_apm_idle = 0;
 932	} else if (jiffies_since_last_check > idle_period) {
 933		unsigned int idle_percentage;
 934
 935		idle_percentage = stime - last_stime;
 936		idle_percentage *= 100;
 937		idle_percentage /= jiffies_since_last_check;
 938		use_apm_idle = (idle_percentage > idle_threshold);
 939		if (apm_info.forbid_idle)
 940			use_apm_idle = 0;
 941	}
 942
 943	last_jiffies = jiffies;
 944	last_stime = stime;
 945
 946	bucket = IDLE_LEAKY_MAX;
 947
 948	while (!need_resched()) {
 949		if (use_apm_idle) {
 950			unsigned int t;
 951
 952			t = jiffies;
 953			switch (apm_do_idle()) {
 954			case 0:
 955				apm_idle_done = 1;
 956				if (t != jiffies) {
 957					if (bucket) {
 958						bucket = IDLE_LEAKY_MAX;
 959						continue;
 960					}
 961				} else if (bucket) {
 962					bucket--;
 963					continue;
 964				}
 965				break;
 966			case 1:
 967				apm_idle_done = 1;
 968				break;
 969			default: /* BIOS refused */
 970				break;
 971			}
 972		}
 973		default_idle();
 974		local_irq_disable();
 975		jiffies_since_last_check = jiffies - last_jiffies;
 976		if (jiffies_since_last_check > idle_period)
 977			goto recalc;
 978	}
 979
 980	if (apm_idle_done)
 981		apm_do_busy();
 982
 983	return index;
 984}
 985
 986/**
 987 *	apm_power_off	-	ask the BIOS to power off
 988 *
 989 *	Handle the power off sequence. This is the one piece of code we
 990 *	will execute even on SMP machines. In order to deal with BIOS
 991 *	bugs we support real mode APM BIOS power off calls. We also make
 992 *	the SMP call on CPU0 as some systems will only honour this call
 993 *	on their first cpu.
 994 */
 995
 996static void apm_power_off(void)
 997{
 998	/* Some bioses don't like being called from CPU != 0 */
 999	if (apm_info.realmode_power_off) {
1000		set_cpus_allowed_ptr(current, cpumask_of(0));
1001		machine_real_restart(MRR_APM);
1002	} else {
1003		(void)set_system_power_state(APM_STATE_OFF);
1004	}
1005}
1006
1007#ifdef CONFIG_APM_DO_ENABLE
1008
1009/**
1010 *	apm_enable_power_management - enable BIOS APM power management
1011 *	@enable: enable yes/no
1012 *
1013 *	Enable or disable the APM BIOS power services.
1014 */
1015
1016static int apm_enable_power_management(int enable)
1017{
1018	u32 eax;
1019	int err;
1020
1021	if ((enable == 0) && (apm_info.bios.flags & APM_BIOS_DISENGAGED))
1022		return APM_NOT_ENGAGED;
1023	if (apm_bios_call_simple(APM_FUNC_ENABLE_PM, APM_DEVICE_BALL,
1024				 enable, &eax, &err))
1025		return err;
1026	if (enable)
1027		apm_info.bios.flags &= ~APM_BIOS_DISABLED;
1028	else
1029		apm_info.bios.flags |= APM_BIOS_DISABLED;
1030	return APM_SUCCESS;
1031}
1032#endif
1033
1034/**
1035 *	apm_get_power_status	-	get current power state
1036 *	@status: returned status
1037 *	@bat: battery info
1038 *	@life: estimated life
1039 *
1040 *	Obtain the current power status from the APM BIOS. We return a
1041 *	status which gives the rough battery status, and current power
1042 *	source. The bat value returned give an estimate as a percentage
1043 *	of life and a status value for the battery. The estimated life
1044 *	if reported is a lifetime in secodnds/minutes at current powwer
1045 *	consumption.
1046 */
1047
1048static int apm_get_power_status(u_short *status, u_short *bat, u_short *life)
1049{
1050	struct apm_bios_call call;
1051
1052	call.func = APM_FUNC_GET_STATUS;
1053	call.ebx = APM_DEVICE_ALL;
1054	call.ecx = 0;
1055
1056	if (apm_info.get_power_status_broken)
1057		return APM_32_UNSUPPORTED;
1058	if (apm_bios_call(&call))
 
 
1059		return call.err;
 
1060	*status = call.ebx;
1061	*bat = call.ecx;
1062	if (apm_info.get_power_status_swabinminutes) {
1063		*life = swab16((u16)call.edx);
1064		*life |= 0x8000;
1065	} else
1066		*life = call.edx;
1067	return APM_SUCCESS;
1068}
1069
1070#if 0
1071static int apm_get_battery_status(u_short which, u_short *status,
1072				  u_short *bat, u_short *life, u_short *nbat)
1073{
1074	u32 eax;
1075	u32 ebx;
1076	u32 ecx;
1077	u32 edx;
1078	u32 esi;
1079
1080	if (apm_info.connection_version < 0x0102) {
1081		/* pretend we only have one battery. */
1082		if (which != 1)
1083			return APM_BAD_DEVICE;
1084		*nbat = 1;
1085		return apm_get_power_status(status, bat, life);
1086	}
1087
1088	if (apm_bios_call(APM_FUNC_GET_STATUS, (0x8000 | (which)), 0, &eax,
1089			  &ebx, &ecx, &edx, &esi))
1090		return (eax >> 8) & 0xff;
1091	*status = ebx;
1092	*bat = ecx;
1093	*life = edx;
1094	*nbat = esi;
1095	return APM_SUCCESS;
1096}
1097#endif
1098
1099/**
1100 *	apm_engage_power_management	-	enable PM on a device
1101 *	@device: identity of device
1102 *	@enable: on/off
1103 *
1104 *	Activate or deactive power management on either a specific device
1105 *	or the entire system (%APM_DEVICE_ALL).
1106 */
1107
1108static int apm_engage_power_management(u_short device, int enable)
1109{
1110	u32 eax;
1111	int err;
1112
1113	if ((enable == 0) && (device == APM_DEVICE_ALL)
1114	    && (apm_info.bios.flags & APM_BIOS_DISABLED))
1115		return APM_DISABLED;
1116	if (apm_bios_call_simple(APM_FUNC_ENGAGE_PM, device, enable,
1117				 &eax, &err))
1118		return err;
1119	if (device == APM_DEVICE_ALL) {
1120		if (enable)
1121			apm_info.bios.flags &= ~APM_BIOS_DISENGAGED;
1122		else
1123			apm_info.bios.flags |= APM_BIOS_DISENGAGED;
1124	}
1125	return APM_SUCCESS;
1126}
1127
1128#if defined(CONFIG_APM_DISPLAY_BLANK) && defined(CONFIG_VT)
1129
1130/**
1131 *	apm_console_blank	-	blank the display
1132 *	@blank: on/off
1133 *
1134 *	Attempt to blank the console, firstly by blanking just video device
1135 *	zero, and if that fails (some BIOSes don't support it) then it blanks
1136 *	all video devices. Typically the BIOS will do laptop backlight and
1137 *	monitor powerdown for us.
1138 */
1139
1140static int apm_console_blank(int blank)
1141{
1142	int error = APM_NOT_ENGAGED; /* silence gcc */
1143	int i;
1144	u_short state;
1145	static const u_short dev[3] = { 0x100, 0x1FF, 0x101 };
1146
1147	state = blank ? APM_STATE_STANDBY : APM_STATE_READY;
1148
1149	for (i = 0; i < ARRAY_SIZE(dev); i++) {
1150		error = set_power_state(dev[i], state);
1151
1152		if ((error == APM_SUCCESS) || (error == APM_NO_ERROR))
1153			return 1;
1154
1155		if (error == APM_NOT_ENGAGED)
1156			break;
1157	}
1158
1159	if (error == APM_NOT_ENGAGED) {
1160		static int tried;
1161		int eng_error;
1162		if (tried++ == 0) {
1163			eng_error = apm_engage_power_management(APM_DEVICE_ALL, 1);
1164			if (eng_error) {
1165				apm_error("set display", error);
1166				apm_error("engage interface", eng_error);
1167				return 0;
1168			} else
1169				return apm_console_blank(blank);
1170		}
1171	}
1172	apm_error("set display", error);
1173	return 0;
1174}
1175#endif
1176
1177static int queue_empty(struct apm_user *as)
1178{
1179	return as->event_head == as->event_tail;
1180}
1181
1182static apm_event_t get_queued_event(struct apm_user *as)
1183{
1184	if (++as->event_tail >= APM_MAX_EVENTS)
1185		as->event_tail = 0;
1186	return as->events[as->event_tail];
1187}
1188
1189static void queue_event(apm_event_t event, struct apm_user *sender)
1190{
1191	struct apm_user *as;
1192
1193	spin_lock(&user_list_lock);
1194	if (user_list == NULL)
1195		goto out;
1196	for (as = user_list; as != NULL; as = as->next) {
1197		if ((as == sender) || (!as->reader))
1198			continue;
1199		if (++as->event_head >= APM_MAX_EVENTS)
1200			as->event_head = 0;
1201
1202		if (as->event_head == as->event_tail) {
1203			static int notified;
1204
1205			if (notified++ == 0)
1206				pr_err("an event queue overflowed\n");
1207			if (++as->event_tail >= APM_MAX_EVENTS)
1208				as->event_tail = 0;
1209		}
1210		as->events[as->event_head] = event;
1211		if (!as->suser || !as->writer)
1212			continue;
1213		switch (event) {
1214		case APM_SYS_SUSPEND:
1215		case APM_USER_SUSPEND:
1216			as->suspends_pending++;
1217			suspends_pending++;
1218			break;
1219
1220		case APM_SYS_STANDBY:
1221		case APM_USER_STANDBY:
1222			as->standbys_pending++;
1223			standbys_pending++;
1224			break;
1225		}
1226	}
1227	wake_up_interruptible(&apm_waitqueue);
1228out:
1229	spin_unlock(&user_list_lock);
1230}
1231
1232static void reinit_timer(void)
1233{
1234#ifdef INIT_TIMER_AFTER_SUSPEND
1235	unsigned long flags;
1236
1237	raw_spin_lock_irqsave(&i8253_lock, flags);
1238	/* set the clock to HZ */
1239	outb_p(0x34, PIT_MODE);		/* binary, mode 2, LSB/MSB, ch 0 */
1240	udelay(10);
1241	outb_p(LATCH & 0xff, PIT_CH0);	/* LSB */
1242	udelay(10);
1243	outb_p(LATCH >> 8, PIT_CH0);	/* MSB */
1244	udelay(10);
1245	raw_spin_unlock_irqrestore(&i8253_lock, flags);
1246#endif
1247}
1248
1249static int suspend(int vetoable)
1250{
1251	int err;
1252	struct apm_user	*as;
1253
1254	dpm_suspend_start(PMSG_SUSPEND);
1255	dpm_suspend_end(PMSG_SUSPEND);
1256
1257	local_irq_disable();
1258	syscore_suspend();
1259
1260	local_irq_enable();
1261
1262	save_processor_state();
1263	err = set_system_power_state(APM_STATE_SUSPEND);
1264	ignore_normal_resume = 1;
1265	restore_processor_state();
1266
1267	local_irq_disable();
1268	reinit_timer();
1269
1270	if (err == APM_NO_ERROR)
1271		err = APM_SUCCESS;
1272	if (err != APM_SUCCESS)
1273		apm_error("suspend", err);
1274	err = (err == APM_SUCCESS) ? 0 : -EIO;
1275
1276	syscore_resume();
1277	local_irq_enable();
1278
1279	dpm_resume_start(PMSG_RESUME);
1280	dpm_resume_end(PMSG_RESUME);
1281
1282	queue_event(APM_NORMAL_RESUME, NULL);
1283	spin_lock(&user_list_lock);
1284	for (as = user_list; as != NULL; as = as->next) {
1285		as->suspend_wait = 0;
1286		as->suspend_result = err;
1287	}
1288	spin_unlock(&user_list_lock);
1289	wake_up_interruptible(&apm_suspend_waitqueue);
1290	return err;
1291}
1292
1293static void standby(void)
1294{
1295	int err;
1296
1297	dpm_suspend_end(PMSG_SUSPEND);
1298
1299	local_irq_disable();
1300	syscore_suspend();
1301	local_irq_enable();
1302
1303	err = set_system_power_state(APM_STATE_STANDBY);
1304	if ((err != APM_SUCCESS) && (err != APM_NO_ERROR))
1305		apm_error("standby", err);
1306
1307	local_irq_disable();
1308	syscore_resume();
1309	local_irq_enable();
1310
1311	dpm_resume_start(PMSG_RESUME);
1312}
1313
1314static apm_event_t get_event(void)
1315{
1316	int error;
1317	apm_event_t event = APM_NO_EVENTS; /* silence gcc */
1318	apm_eventinfo_t	info;
1319
1320	static int notified;
1321
1322	/* we don't use the eventinfo */
1323	error = apm_get_event(&event, &info);
1324	if (error == APM_SUCCESS)
1325		return event;
1326
1327	if ((error != APM_NO_EVENTS) && (notified++ == 0))
1328		apm_error("get_event", error);
1329
1330	return 0;
1331}
1332
1333static void check_events(void)
1334{
1335	apm_event_t event;
1336	static unsigned long last_resume;
1337	static int ignore_bounce;
1338
1339	while ((event = get_event()) != 0) {
1340		if (debug) {
1341			if (event <= NR_APM_EVENT_NAME)
1342				printk(KERN_DEBUG "apm: received %s notify\n",
1343				       apm_event_name[event - 1]);
1344			else
1345				printk(KERN_DEBUG "apm: received unknown "
1346				       "event 0x%02x\n", event);
1347		}
1348		if (ignore_bounce
1349		    && (time_after(jiffies, last_resume + bounce_interval)))
1350			ignore_bounce = 0;
1351
1352		switch (event) {
1353		case APM_SYS_STANDBY:
1354		case APM_USER_STANDBY:
1355			queue_event(event, NULL);
1356			if (standbys_pending <= 0)
1357				standby();
1358			break;
1359
1360		case APM_USER_SUSPEND:
1361#ifdef CONFIG_APM_IGNORE_USER_SUSPEND
1362			if (apm_info.connection_version > 0x100)
1363				set_system_power_state(APM_STATE_REJECT);
1364			break;
1365#endif
1366		case APM_SYS_SUSPEND:
1367			if (ignore_bounce) {
1368				if (apm_info.connection_version > 0x100)
1369					set_system_power_state(APM_STATE_REJECT);
1370				break;
1371			}
1372			/*
1373			 * If we are already processing a SUSPEND,
1374			 * then further SUSPEND events from the BIOS
1375			 * will be ignored.  We also return here to
1376			 * cope with the fact that the Thinkpads keep
1377			 * sending a SUSPEND event until something else
1378			 * happens!
1379			 */
1380			if (ignore_sys_suspend)
1381				return;
1382			ignore_sys_suspend = 1;
1383			queue_event(event, NULL);
1384			if (suspends_pending <= 0)
1385				(void) suspend(1);
1386			break;
1387
1388		case APM_NORMAL_RESUME:
1389		case APM_CRITICAL_RESUME:
1390		case APM_STANDBY_RESUME:
1391			ignore_sys_suspend = 0;
1392			last_resume = jiffies;
1393			ignore_bounce = 1;
1394			if ((event != APM_NORMAL_RESUME)
1395			    || (ignore_normal_resume == 0)) {
1396				dpm_resume_end(PMSG_RESUME);
1397				queue_event(event, NULL);
1398			}
1399			ignore_normal_resume = 0;
1400			break;
1401
1402		case APM_CAPABILITY_CHANGE:
1403		case APM_LOW_BATTERY:
1404		case APM_POWER_STATUS_CHANGE:
1405			queue_event(event, NULL);
1406			/* If needed, notify drivers here */
1407			break;
1408
1409		case APM_UPDATE_TIME:
1410			break;
1411
1412		case APM_CRITICAL_SUSPEND:
1413			/*
1414			 * We are not allowed to reject a critical suspend.
1415			 */
1416			(void)suspend(0);
1417			break;
1418		}
1419	}
1420}
1421
1422static void apm_event_handler(void)
1423{
1424	static int pending_count = 4;
1425	int err;
1426
1427	if ((standbys_pending > 0) || (suspends_pending > 0)) {
1428		if ((apm_info.connection_version > 0x100) &&
1429		    (pending_count-- <= 0)) {
1430			pending_count = 4;
1431			if (debug)
1432				printk(KERN_DEBUG "apm: setting state busy\n");
1433			err = set_system_power_state(APM_STATE_BUSY);
1434			if (err)
1435				apm_error("busy", err);
1436		}
1437	} else
1438		pending_count = 4;
1439	check_events();
1440}
1441
1442/*
1443 * This is the APM thread main loop.
1444 */
1445
1446static void apm_mainloop(void)
1447{
1448	DECLARE_WAITQUEUE(wait, current);
1449
1450	add_wait_queue(&apm_waitqueue, &wait);
1451	set_current_state(TASK_INTERRUPTIBLE);
1452	for (;;) {
1453		schedule_timeout(APM_CHECK_TIMEOUT);
1454		if (kthread_should_stop())
1455			break;
1456		/*
1457		 * Ok, check all events, check for idle (and mark us sleeping
1458		 * so as not to count towards the load average)..
1459		 */
1460		set_current_state(TASK_INTERRUPTIBLE);
1461		apm_event_handler();
1462	}
1463	remove_wait_queue(&apm_waitqueue, &wait);
1464}
1465
1466static int check_apm_user(struct apm_user *as, const char *func)
1467{
1468	if (as == NULL || as->magic != APM_BIOS_MAGIC) {
1469		pr_err("%s passed bad filp\n", func);
1470		return 1;
1471	}
1472	return 0;
1473}
1474
1475static ssize_t do_read(struct file *fp, char __user *buf, size_t count, loff_t *ppos)
1476{
1477	struct apm_user *as;
1478	int i;
1479	apm_event_t event;
1480
1481	as = fp->private_data;
1482	if (check_apm_user(as, "read"))
1483		return -EIO;
1484	if ((int)count < sizeof(apm_event_t))
1485		return -EINVAL;
1486	if ((queue_empty(as)) && (fp->f_flags & O_NONBLOCK))
1487		return -EAGAIN;
1488	wait_event_interruptible(apm_waitqueue, !queue_empty(as));
1489	i = count;
1490	while ((i >= sizeof(event)) && !queue_empty(as)) {
1491		event = get_queued_event(as);
1492		if (copy_to_user(buf, &event, sizeof(event))) {
1493			if (i < count)
1494				break;
1495			return -EFAULT;
1496		}
1497		switch (event) {
1498		case APM_SYS_SUSPEND:
1499		case APM_USER_SUSPEND:
1500			as->suspends_read++;
1501			break;
1502
1503		case APM_SYS_STANDBY:
1504		case APM_USER_STANDBY:
1505			as->standbys_read++;
1506			break;
1507		}
1508		buf += sizeof(event);
1509		i -= sizeof(event);
1510	}
1511	if (i < count)
1512		return count - i;
1513	if (signal_pending(current))
1514		return -ERESTARTSYS;
1515	return 0;
1516}
1517
1518static unsigned int do_poll(struct file *fp, poll_table *wait)
1519{
1520	struct apm_user *as;
1521
1522	as = fp->private_data;
1523	if (check_apm_user(as, "poll"))
1524		return 0;
1525	poll_wait(fp, &apm_waitqueue, wait);
1526	if (!queue_empty(as))
1527		return POLLIN | POLLRDNORM;
1528	return 0;
1529}
1530
1531static long do_ioctl(struct file *filp, u_int cmd, u_long arg)
1532{
1533	struct apm_user *as;
1534	int ret;
1535
1536	as = filp->private_data;
1537	if (check_apm_user(as, "ioctl"))
1538		return -EIO;
1539	if (!as->suser || !as->writer)
1540		return -EPERM;
1541	switch (cmd) {
1542	case APM_IOC_STANDBY:
1543		mutex_lock(&apm_mutex);
1544		if (as->standbys_read > 0) {
1545			as->standbys_read--;
1546			as->standbys_pending--;
1547			standbys_pending--;
1548		} else
1549			queue_event(APM_USER_STANDBY, as);
1550		if (standbys_pending <= 0)
1551			standby();
1552		mutex_unlock(&apm_mutex);
1553		break;
1554	case APM_IOC_SUSPEND:
1555		mutex_lock(&apm_mutex);
1556		if (as->suspends_read > 0) {
1557			as->suspends_read--;
1558			as->suspends_pending--;
1559			suspends_pending--;
1560		} else
1561			queue_event(APM_USER_SUSPEND, as);
1562		if (suspends_pending <= 0) {
1563			ret = suspend(1);
1564			mutex_unlock(&apm_mutex);
1565		} else {
1566			as->suspend_wait = 1;
1567			mutex_unlock(&apm_mutex);
1568			wait_event_interruptible(apm_suspend_waitqueue,
1569					as->suspend_wait == 0);
1570			ret = as->suspend_result;
1571		}
1572		return ret;
1573	default:
1574		return -ENOTTY;
1575	}
1576	return 0;
1577}
1578
1579static int do_release(struct inode *inode, struct file *filp)
1580{
1581	struct apm_user *as;
1582
1583	as = filp->private_data;
1584	if (check_apm_user(as, "release"))
1585		return 0;
1586	filp->private_data = NULL;
1587	if (as->standbys_pending > 0) {
1588		standbys_pending -= as->standbys_pending;
1589		if (standbys_pending <= 0)
1590			standby();
1591	}
1592	if (as->suspends_pending > 0) {
1593		suspends_pending -= as->suspends_pending;
1594		if (suspends_pending <= 0)
1595			(void) suspend(1);
1596	}
1597	spin_lock(&user_list_lock);
1598	if (user_list == as)
1599		user_list = as->next;
1600	else {
1601		struct apm_user *as1;
1602
1603		for (as1 = user_list;
1604		     (as1 != NULL) && (as1->next != as);
1605		     as1 = as1->next)
1606			;
1607		if (as1 == NULL)
1608			pr_err("filp not in user list\n");
1609		else
1610			as1->next = as->next;
1611	}
1612	spin_unlock(&user_list_lock);
1613	kfree(as);
1614	return 0;
1615}
1616
1617static int do_open(struct inode *inode, struct file *filp)
1618{
1619	struct apm_user *as;
1620
1621	as = kmalloc(sizeof(*as), GFP_KERNEL);
1622	if (as == NULL)
1623		return -ENOMEM;
1624
1625	as->magic = APM_BIOS_MAGIC;
1626	as->event_tail = as->event_head = 0;
1627	as->suspends_pending = as->standbys_pending = 0;
1628	as->suspends_read = as->standbys_read = 0;
1629	/*
1630	 * XXX - this is a tiny bit broken, when we consider BSD
1631	 * process accounting. If the device is opened by root, we
1632	 * instantly flag that we used superuser privs. Who knows,
1633	 * we might close the device immediately without doing a
1634	 * privileged operation -- cevans
1635	 */
1636	as->suser = capable(CAP_SYS_ADMIN);
1637	as->writer = (filp->f_mode & FMODE_WRITE) == FMODE_WRITE;
1638	as->reader = (filp->f_mode & FMODE_READ) == FMODE_READ;
1639	spin_lock(&user_list_lock);
1640	as->next = user_list;
1641	user_list = as;
1642	spin_unlock(&user_list_lock);
1643	filp->private_data = as;
1644	return 0;
1645}
1646
1647static int proc_apm_show(struct seq_file *m, void *v)
1648{
1649	unsigned short	bx;
1650	unsigned short	cx;
1651	unsigned short	dx;
1652	int		error;
1653	unsigned short  ac_line_status = 0xff;
1654	unsigned short  battery_status = 0xff;
1655	unsigned short  battery_flag   = 0xff;
1656	int		percentage     = -1;
1657	int             time_units     = -1;
1658	char            *units         = "?";
1659
1660	if ((num_online_cpus() == 1) &&
1661	    !(error = apm_get_power_status(&bx, &cx, &dx))) {
1662		ac_line_status = (bx >> 8) & 0xff;
1663		battery_status = bx & 0xff;
1664		if ((cx & 0xff) != 0xff)
1665			percentage = cx & 0xff;
1666
1667		if (apm_info.connection_version > 0x100) {
1668			battery_flag = (cx >> 8) & 0xff;
1669			if (dx != 0xffff) {
1670				units = (dx & 0x8000) ? "min" : "sec";
1671				time_units = dx & 0x7fff;
1672			}
1673		}
1674	}
1675	/* Arguments, with symbols from linux/apm_bios.h.  Information is
1676	   from the Get Power Status (0x0a) call unless otherwise noted.
1677
1678	   0) Linux driver version (this will change if format changes)
1679	   1) APM BIOS Version.  Usually 1.0, 1.1 or 1.2.
1680	   2) APM flags from APM Installation Check (0x00):
1681	      bit 0: APM_16_BIT_SUPPORT
1682	      bit 1: APM_32_BIT_SUPPORT
1683	      bit 2: APM_IDLE_SLOWS_CLOCK
1684	      bit 3: APM_BIOS_DISABLED
1685	      bit 4: APM_BIOS_DISENGAGED
1686	   3) AC line status
1687	      0x00: Off-line
1688	      0x01: On-line
1689	      0x02: On backup power (BIOS >= 1.1 only)
1690	      0xff: Unknown
1691	   4) Battery status
1692	      0x00: High
1693	      0x01: Low
1694	      0x02: Critical
1695	      0x03: Charging
1696	      0x04: Selected battery not present (BIOS >= 1.2 only)
1697	      0xff: Unknown
1698	   5) Battery flag
1699	      bit 0: High
1700	      bit 1: Low
1701	      bit 2: Critical
1702	      bit 3: Charging
1703	      bit 7: No system battery
1704	      0xff: Unknown
1705	   6) Remaining battery life (percentage of charge):
1706	      0-100: valid
1707	      -1: Unknown
1708	   7) Remaining battery life (time units):
1709	      Number of remaining minutes or seconds
1710	      -1: Unknown
1711	   8) min = minutes; sec = seconds */
1712
1713	seq_printf(m, "%s %d.%d 0x%02x 0x%02x 0x%02x 0x%02x %d%% %d %s\n",
1714		   driver_version,
1715		   (apm_info.bios.version >> 8) & 0xff,
1716		   apm_info.bios.version & 0xff,
1717		   apm_info.bios.flags,
1718		   ac_line_status,
1719		   battery_status,
1720		   battery_flag,
1721		   percentage,
1722		   time_units,
1723		   units);
1724	return 0;
1725}
1726
1727static int proc_apm_open(struct inode *inode, struct file *file)
1728{
1729	return single_open(file, proc_apm_show, NULL);
1730}
1731
1732static const struct file_operations apm_file_ops = {
1733	.owner		= THIS_MODULE,
1734	.open		= proc_apm_open,
1735	.read		= seq_read,
1736	.llseek		= seq_lseek,
1737	.release	= single_release,
1738};
1739
1740static int apm(void *unused)
1741{
1742	unsigned short	bx;
1743	unsigned short	cx;
1744	unsigned short	dx;
1745	int		error;
1746	char 		*power_stat;
1747	char 		*bat_stat;
1748
1749	/* 2002/08/01 - WT
1750	 * This is to avoid random crashes at boot time during initialization
1751	 * on SMP systems in case of "apm=power-off" mode. Seen on ASUS A7M266D.
1752	 * Some bioses don't like being called from CPU != 0.
1753	 * Method suggested by Ingo Molnar.
1754	 */
1755	set_cpus_allowed_ptr(current, cpumask_of(0));
1756	BUG_ON(smp_processor_id() != 0);
1757
1758	if (apm_info.connection_version == 0) {
1759		apm_info.connection_version = apm_info.bios.version;
1760		if (apm_info.connection_version > 0x100) {
1761			/*
1762			 * We only support BIOSs up to version 1.2
1763			 */
1764			if (apm_info.connection_version > 0x0102)
1765				apm_info.connection_version = 0x0102;
1766			error = apm_driver_version(&apm_info.connection_version);
1767			if (error != APM_SUCCESS) {
1768				apm_error("driver version", error);
1769				/* Fall back to an APM 1.0 connection. */
1770				apm_info.connection_version = 0x100;
1771			}
1772		}
1773	}
1774
1775	if (debug)
1776		printk(KERN_INFO "apm: Connection version %d.%d\n",
1777			(apm_info.connection_version >> 8) & 0xff,
1778			apm_info.connection_version & 0xff);
1779
1780#ifdef CONFIG_APM_DO_ENABLE
1781	if (apm_info.bios.flags & APM_BIOS_DISABLED) {
1782		/*
1783		 * This call causes my NEC UltraLite Versa 33/C to hang if it
1784		 * is booted with PM disabled but not in the docking station.
1785		 * Unfortunate ...
1786		 */
1787		error = apm_enable_power_management(1);
1788		if (error) {
1789			apm_error("enable power management", error);
1790			return -1;
1791		}
1792	}
1793#endif
1794
1795	if ((apm_info.bios.flags & APM_BIOS_DISENGAGED)
1796	    && (apm_info.connection_version > 0x0100)) {
1797		error = apm_engage_power_management(APM_DEVICE_ALL, 1);
1798		if (error) {
1799			apm_error("engage power management", error);
1800			return -1;
1801		}
1802	}
1803
1804	if (debug && (num_online_cpus() == 1 || smp)) {
1805		error = apm_get_power_status(&bx, &cx, &dx);
1806		if (error)
1807			printk(KERN_INFO "apm: power status not available\n");
1808		else {
1809			switch ((bx >> 8) & 0xff) {
1810			case 0:
1811				power_stat = "off line";
1812				break;
1813			case 1:
1814				power_stat = "on line";
1815				break;
1816			case 2:
1817				power_stat = "on backup power";
1818				break;
1819			default:
1820				power_stat = "unknown";
1821				break;
1822			}
1823			switch (bx & 0xff) {
1824			case 0:
1825				bat_stat = "high";
1826				break;
1827			case 1:
1828				bat_stat = "low";
1829				break;
1830			case 2:
1831				bat_stat = "critical";
1832				break;
1833			case 3:
1834				bat_stat = "charging";
1835				break;
1836			default:
1837				bat_stat = "unknown";
1838				break;
1839			}
1840			printk(KERN_INFO
1841			       "apm: AC %s, battery status %s, battery life ",
1842			       power_stat, bat_stat);
1843			if ((cx & 0xff) == 0xff)
1844				printk("unknown\n");
1845			else
1846				printk("%d%%\n", cx & 0xff);
1847			if (apm_info.connection_version > 0x100) {
1848				printk(KERN_INFO
1849				       "apm: battery flag 0x%02x, battery life ",
1850				       (cx >> 8) & 0xff);
1851				if (dx == 0xffff)
1852					printk("unknown\n");
1853				else
1854					printk("%d %s\n", dx & 0x7fff,
1855					       (dx & 0x8000) ?
1856					       "minutes" : "seconds");
1857			}
1858		}
1859	}
1860
1861	/* Install our power off handler.. */
1862	if (power_off)
1863		pm_power_off = apm_power_off;
1864
1865	if (num_online_cpus() == 1 || smp) {
1866#if defined(CONFIG_APM_DISPLAY_BLANK) && defined(CONFIG_VT)
1867		console_blank_hook = apm_console_blank;
1868#endif
1869		apm_mainloop();
1870#if defined(CONFIG_APM_DISPLAY_BLANK) && defined(CONFIG_VT)
1871		console_blank_hook = NULL;
1872#endif
1873	}
1874
1875	return 0;
1876}
1877
1878#ifndef MODULE
1879static int __init apm_setup(char *str)
1880{
1881	int invert;
1882
1883	while ((str != NULL) && (*str != '\0')) {
1884		if (strncmp(str, "off", 3) == 0)
1885			apm_disabled = 1;
1886		if (strncmp(str, "on", 2) == 0)
1887			apm_disabled = 0;
1888		if ((strncmp(str, "bounce-interval=", 16) == 0) ||
1889		    (strncmp(str, "bounce_interval=", 16) == 0))
1890			bounce_interval = simple_strtol(str + 16, NULL, 0);
1891		if ((strncmp(str, "idle-threshold=", 15) == 0) ||
1892		    (strncmp(str, "idle_threshold=", 15) == 0))
1893			idle_threshold = simple_strtol(str + 15, NULL, 0);
1894		if ((strncmp(str, "idle-period=", 12) == 0) ||
1895		    (strncmp(str, "idle_period=", 12) == 0))
1896			idle_period = simple_strtol(str + 12, NULL, 0);
1897		invert = (strncmp(str, "no-", 3) == 0) ||
1898			(strncmp(str, "no_", 3) == 0);
1899		if (invert)
1900			str += 3;
1901		if (strncmp(str, "debug", 5) == 0)
1902			debug = !invert;
1903		if ((strncmp(str, "power-off", 9) == 0) ||
1904		    (strncmp(str, "power_off", 9) == 0))
1905			power_off = !invert;
1906		if (strncmp(str, "smp", 3) == 0) {
1907			smp = !invert;
1908			idle_threshold = 100;
1909		}
1910		if ((strncmp(str, "allow-ints", 10) == 0) ||
1911		    (strncmp(str, "allow_ints", 10) == 0))
1912			apm_info.allow_ints = !invert;
1913		if ((strncmp(str, "broken-psr", 10) == 0) ||
1914		    (strncmp(str, "broken_psr", 10) == 0))
1915			apm_info.get_power_status_broken = !invert;
1916		if ((strncmp(str, "realmode-power-off", 18) == 0) ||
1917		    (strncmp(str, "realmode_power_off", 18) == 0))
1918			apm_info.realmode_power_off = !invert;
1919		str = strchr(str, ',');
1920		if (str != NULL)
1921			str += strspn(str, ", \t");
1922	}
1923	return 1;
1924}
1925
1926__setup("apm=", apm_setup);
1927#endif
1928
1929static const struct file_operations apm_bios_fops = {
1930	.owner		= THIS_MODULE,
1931	.read		= do_read,
1932	.poll		= do_poll,
1933	.unlocked_ioctl	= do_ioctl,
1934	.open		= do_open,
1935	.release	= do_release,
1936	.llseek		= noop_llseek,
1937};
1938
1939static struct miscdevice apm_device = {
1940	APM_MINOR_DEV,
1941	"apm_bios",
1942	&apm_bios_fops
1943};
1944
1945
1946/* Simple "print if true" callback */
1947static int __init print_if_true(const struct dmi_system_id *d)
1948{
1949	printk("%s\n", d->ident);
1950	return 0;
1951}
1952
1953/*
1954 * Some Bioses enable the PS/2 mouse (touchpad) at resume, even if it was
1955 * disabled before the suspend. Linux used to get terribly confused by that.
1956 */
1957static int __init broken_ps2_resume(const struct dmi_system_id *d)
1958{
1959	printk(KERN_INFO "%s machine detected. Mousepad Resume Bug "
1960	       "workaround hopefully not needed.\n", d->ident);
1961	return 0;
1962}
1963
1964/* Some bioses have a broken protected mode poweroff and need to use realmode */
1965static int __init set_realmode_power_off(const struct dmi_system_id *d)
1966{
1967	if (apm_info.realmode_power_off == 0) {
1968		apm_info.realmode_power_off = 1;
1969		printk(KERN_INFO "%s bios detected. "
1970		       "Using realmode poweroff only.\n", d->ident);
1971	}
1972	return 0;
1973}
1974
1975/* Some laptops require interrupts to be enabled during APM calls */
1976static int __init set_apm_ints(const struct dmi_system_id *d)
1977{
1978	if (apm_info.allow_ints == 0) {
1979		apm_info.allow_ints = 1;
1980		printk(KERN_INFO "%s machine detected. "
1981		       "Enabling interrupts during APM calls.\n", d->ident);
1982	}
1983	return 0;
1984}
1985
1986/* Some APM bioses corrupt memory or just plain do not work */
1987static int __init apm_is_horked(const struct dmi_system_id *d)
1988{
1989	if (apm_info.disabled == 0) {
1990		apm_info.disabled = 1;
1991		printk(KERN_INFO "%s machine detected. "
1992		       "Disabling APM.\n", d->ident);
1993	}
1994	return 0;
1995}
1996
1997static int __init apm_is_horked_d850md(const struct dmi_system_id *d)
1998{
1999	if (apm_info.disabled == 0) {
2000		apm_info.disabled = 1;
2001		printk(KERN_INFO "%s machine detected. "
2002		       "Disabling APM.\n", d->ident);
2003		printk(KERN_INFO "This bug is fixed in bios P15 which is available for\n");
2004		printk(KERN_INFO "download from support.intel.com\n");
2005	}
2006	return 0;
2007}
2008
2009/* Some APM bioses hang on APM idle calls */
2010static int __init apm_likes_to_melt(const struct dmi_system_id *d)
2011{
2012	if (apm_info.forbid_idle == 0) {
2013		apm_info.forbid_idle = 1;
2014		printk(KERN_INFO "%s machine detected. "
2015		       "Disabling APM idle calls.\n", d->ident);
2016	}
2017	return 0;
2018}
2019
2020/*
2021 *  Check for clue free BIOS implementations who use
2022 *  the following QA technique
2023 *
2024 *      [ Write BIOS Code ]<------
2025 *               |                ^
2026 *      < Does it Compile >----N--
2027 *               |Y               ^
2028 *	< Does it Boot Win98 >-N--
2029 *               |Y
2030 *           [Ship It]
2031 *
2032 *	Phoenix A04  08/24/2000 is known bad (Dell Inspiron 5000e)
2033 *	Phoenix A07  09/29/2000 is known good (Dell Inspiron 5000)
2034 */
2035static int __init broken_apm_power(const struct dmi_system_id *d)
2036{
2037	apm_info.get_power_status_broken = 1;
2038	printk(KERN_WARNING "BIOS strings suggest APM bugs, "
2039	       "disabling power status reporting.\n");
2040	return 0;
2041}
2042
2043/*
2044 * This bios swaps the APM minute reporting bytes over (Many sony laptops
2045 * have this problem).
2046 */
2047static int __init swab_apm_power_in_minutes(const struct dmi_system_id *d)
2048{
2049	apm_info.get_power_status_swabinminutes = 1;
2050	printk(KERN_WARNING "BIOS strings suggest APM reports battery life "
2051	       "in minutes and wrong byte order.\n");
2052	return 0;
2053}
2054
2055static struct dmi_system_id __initdata apm_dmi_table[] = {
2056	{
2057		print_if_true,
2058		KERN_WARNING "IBM T23 - BIOS 1.03b+ and controller firmware 1.02+ may be needed for Linux APM.",
2059		{	DMI_MATCH(DMI_SYS_VENDOR, "IBM"),
2060			DMI_MATCH(DMI_BIOS_VERSION, "1AET38WW (1.01b)"), },
2061	},
2062	{	/* Handle problems with APM on the C600 */
2063		broken_ps2_resume, "Dell Latitude C600",
2064		{	DMI_MATCH(DMI_SYS_VENDOR, "Dell"),
2065			DMI_MATCH(DMI_PRODUCT_NAME, "Latitude C600"), },
2066	},
2067	{	/* Allow interrupts during suspend on Dell Latitude laptops*/
2068		set_apm_ints, "Dell Latitude",
2069		{	DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
2070			DMI_MATCH(DMI_PRODUCT_NAME, "Latitude C510"), }
2071	},
2072	{	/* APM crashes */
2073		apm_is_horked, "Dell Inspiron 2500",
2074		{	DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
2075			DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 2500"),
2076			DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2077			DMI_MATCH(DMI_BIOS_VERSION, "A11"), },
2078	},
2079	{	/* Allow interrupts during suspend on Dell Inspiron laptops*/
2080		set_apm_ints, "Dell Inspiron", {
2081			DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
2082			DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 4000"), },
2083	},
2084	{	/* Handle problems with APM on Inspiron 5000e */
2085		broken_apm_power, "Dell Inspiron 5000e",
2086		{	DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2087			DMI_MATCH(DMI_BIOS_VERSION, "A04"),
2088			DMI_MATCH(DMI_BIOS_DATE, "08/24/2000"), },
2089	},
2090	{	/* Handle problems with APM on Inspiron 2500 */
2091		broken_apm_power, "Dell Inspiron 2500",
2092		{	DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2093			DMI_MATCH(DMI_BIOS_VERSION, "A12"),
2094			DMI_MATCH(DMI_BIOS_DATE, "02/04/2002"), },
2095	},
2096	{	/* APM crashes */
2097		apm_is_horked, "Dell Dimension 4100",
2098		{	DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
2099			DMI_MATCH(DMI_PRODUCT_NAME, "XPS-Z"),
2100			DMI_MATCH(DMI_BIOS_VENDOR, "Intel Corp."),
2101			DMI_MATCH(DMI_BIOS_VERSION, "A11"), },
2102	},
2103	{	/* Allow interrupts during suspend on Compaq Laptops*/
2104		set_apm_ints, "Compaq 12XL125",
2105		{	DMI_MATCH(DMI_SYS_VENDOR, "Compaq"),
2106			DMI_MATCH(DMI_PRODUCT_NAME, "Compaq PC"),
2107			DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2108			DMI_MATCH(DMI_BIOS_VERSION, "4.06"), },
2109	},
2110	{	/* Allow interrupts during APM or the clock goes slow */
2111		set_apm_ints, "ASUSTeK",
2112		{	DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK Computer Inc."),
2113			DMI_MATCH(DMI_PRODUCT_NAME, "L8400K series Notebook PC"), },
2114	},
2115	{	/* APM blows on shutdown */
2116		apm_is_horked, "ABIT KX7-333[R]",
2117		{	DMI_MATCH(DMI_BOARD_VENDOR, "ABIT"),
2118			DMI_MATCH(DMI_BOARD_NAME, "VT8367-8233A (KX7-333[R])"), },
2119	},
2120	{	/* APM crashes */
2121		apm_is_horked, "Trigem Delhi3",
2122		{	DMI_MATCH(DMI_SYS_VENDOR, "TriGem Computer, Inc"),
2123			DMI_MATCH(DMI_PRODUCT_NAME, "Delhi3"), },
2124	},
2125	{	/* APM crashes */
2126		apm_is_horked, "Fujitsu-Siemens",
2127		{	DMI_MATCH(DMI_BIOS_VENDOR, "hoenix/FUJITSU SIEMENS"),
2128			DMI_MATCH(DMI_BIOS_VERSION, "Version1.01"), },
2129	},
2130	{	/* APM crashes */
2131		apm_is_horked_d850md, "Intel D850MD",
2132		{	DMI_MATCH(DMI_BIOS_VENDOR, "Intel Corp."),
2133			DMI_MATCH(DMI_BIOS_VERSION, "MV85010A.86A.0016.P07.0201251536"), },
2134	},
2135	{	/* APM crashes */
2136		apm_is_horked, "Intel D810EMO",
2137		{	DMI_MATCH(DMI_BIOS_VENDOR, "Intel Corp."),
2138			DMI_MATCH(DMI_BIOS_VERSION, "MO81010A.86A.0008.P04.0004170800"), },
2139	},
2140	{	/* APM crashes */
2141		apm_is_horked, "Dell XPS-Z",
2142		{	DMI_MATCH(DMI_BIOS_VENDOR, "Intel Corp."),
2143			DMI_MATCH(DMI_BIOS_VERSION, "A11"),
2144			DMI_MATCH(DMI_PRODUCT_NAME, "XPS-Z"), },
2145	},
2146	{	/* APM crashes */
2147		apm_is_horked, "Sharp PC-PJ/AX",
2148		{	DMI_MATCH(DMI_SYS_VENDOR, "SHARP"),
2149			DMI_MATCH(DMI_PRODUCT_NAME, "PC-PJ/AX"),
2150			DMI_MATCH(DMI_BIOS_VENDOR, "SystemSoft"),
2151			DMI_MATCH(DMI_BIOS_VERSION, "Version R2.08"), },
2152	},
2153	{	/* APM crashes */
2154		apm_is_horked, "Dell Inspiron 2500",
2155		{	DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
2156			DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 2500"),
2157			DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2158			DMI_MATCH(DMI_BIOS_VERSION, "A11"), },
2159	},
2160	{	/* APM idle hangs */
2161		apm_likes_to_melt, "Jabil AMD",
2162		{	DMI_MATCH(DMI_BIOS_VENDOR, "American Megatrends Inc."),
2163			DMI_MATCH(DMI_BIOS_VERSION, "0AASNP06"), },
2164	},
2165	{	/* APM idle hangs */
2166		apm_likes_to_melt, "AMI Bios",
2167		{	DMI_MATCH(DMI_BIOS_VENDOR, "American Megatrends Inc."),
2168			DMI_MATCH(DMI_BIOS_VERSION, "0AASNP05"), },
2169	},
2170	{	/* Handle problems with APM on Sony Vaio PCG-N505X(DE) */
2171		swab_apm_power_in_minutes, "Sony VAIO",
2172		{	DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2173			DMI_MATCH(DMI_BIOS_VERSION, "R0206H"),
2174			DMI_MATCH(DMI_BIOS_DATE, "08/23/99"), },
2175	},
2176	{	/* Handle problems with APM on Sony Vaio PCG-N505VX */
2177		swab_apm_power_in_minutes, "Sony VAIO",
2178		{	DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2179			DMI_MATCH(DMI_BIOS_VERSION, "W2K06H0"),
2180			DMI_MATCH(DMI_BIOS_DATE, "02/03/00"), },
2181	},
2182	{	/* Handle problems with APM on Sony Vaio PCG-XG29 */
2183		swab_apm_power_in_minutes, "Sony VAIO",
2184		{	DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2185			DMI_MATCH(DMI_BIOS_VERSION, "R0117A0"),
2186			DMI_MATCH(DMI_BIOS_DATE, "04/25/00"), },
2187	},
2188	{	/* Handle problems with APM on Sony Vaio PCG-Z600NE */
2189		swab_apm_power_in_minutes, "Sony VAIO",
2190		{	DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2191			DMI_MATCH(DMI_BIOS_VERSION, "R0121Z1"),
2192			DMI_MATCH(DMI_BIOS_DATE, "05/11/00"), },
2193	},
2194	{	/* Handle problems with APM on Sony Vaio PCG-Z600NE */
2195		swab_apm_power_in_minutes, "Sony VAIO",
2196		{	DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2197			DMI_MATCH(DMI_BIOS_VERSION, "WME01Z1"),
2198			DMI_MATCH(DMI_BIOS_DATE, "08/11/00"), },
2199	},
2200	{	/* Handle problems with APM on Sony Vaio PCG-Z600LEK(DE) */
2201		swab_apm_power_in_minutes, "Sony VAIO",
2202		{	DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2203			DMI_MATCH(DMI_BIOS_VERSION, "R0206Z3"),
2204			DMI_MATCH(DMI_BIOS_DATE, "12/25/00"), },
2205	},
2206	{	/* Handle problems with APM on Sony Vaio PCG-Z505LS */
2207		swab_apm_power_in_minutes, "Sony VAIO",
2208		{	DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2209			DMI_MATCH(DMI_BIOS_VERSION, "R0203D0"),
2210			DMI_MATCH(DMI_BIOS_DATE, "05/12/00"), },
2211	},
2212	{	/* Handle problems with APM on Sony Vaio PCG-Z505LS */
2213		swab_apm_power_in_minutes, "Sony VAIO",
2214		{	DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2215			DMI_MATCH(DMI_BIOS_VERSION, "R0203Z3"),
2216			DMI_MATCH(DMI_BIOS_DATE, "08/25/00"), },
2217	},
2218	{	/* Handle problems with APM on Sony Vaio PCG-Z505LS (with updated BIOS) */
2219		swab_apm_power_in_minutes, "Sony VAIO",
2220		{	DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2221			DMI_MATCH(DMI_BIOS_VERSION, "R0209Z3"),
2222			DMI_MATCH(DMI_BIOS_DATE, "05/12/01"), },
2223	},
2224	{	/* Handle problems with APM on Sony Vaio PCG-F104K */
2225		swab_apm_power_in_minutes, "Sony VAIO",
2226		{	DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2227			DMI_MATCH(DMI_BIOS_VERSION, "R0204K2"),
2228			DMI_MATCH(DMI_BIOS_DATE, "08/28/00"), },
2229	},
2230
2231	{	/* Handle problems with APM on Sony Vaio PCG-C1VN/C1VE */
2232		swab_apm_power_in_minutes, "Sony VAIO",
2233		{	DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2234			DMI_MATCH(DMI_BIOS_VERSION, "R0208P1"),
2235			DMI_MATCH(DMI_BIOS_DATE, "11/09/00"), },
2236	},
2237	{	/* Handle problems with APM on Sony Vaio PCG-C1VE */
2238		swab_apm_power_in_minutes, "Sony VAIO",
2239		{	DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2240			DMI_MATCH(DMI_BIOS_VERSION, "R0204P1"),
2241			DMI_MATCH(DMI_BIOS_DATE, "09/12/00"), },
2242	},
2243	{	/* Handle problems with APM on Sony Vaio PCG-C1VE */
2244		swab_apm_power_in_minutes, "Sony VAIO",
2245		{	DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2246			DMI_MATCH(DMI_BIOS_VERSION, "WXPO1Z3"),
2247			DMI_MATCH(DMI_BIOS_DATE, "10/26/01"), },
2248	},
2249	{	/* broken PM poweroff bios */
2250		set_realmode_power_off, "Award Software v4.60 PGMA",
2251		{	DMI_MATCH(DMI_BIOS_VENDOR, "Award Software International, Inc."),
2252			DMI_MATCH(DMI_BIOS_VERSION, "4.60 PGMA"),
2253			DMI_MATCH(DMI_BIOS_DATE, "134526184"), },
2254	},
2255
2256	/* Generic per vendor APM settings  */
2257
2258	{	/* Allow interrupts during suspend on IBM laptops */
2259		set_apm_ints, "IBM",
2260		{	DMI_MATCH(DMI_SYS_VENDOR, "IBM"), },
2261	},
2262
2263	{ }
2264};
2265
2266/*
2267 * Just start the APM thread. We do NOT want to do APM BIOS
2268 * calls from anything but the APM thread, if for no other reason
2269 * than the fact that we don't trust the APM BIOS. This way,
2270 * most common APM BIOS problems that lead to protection errors
2271 * etc will have at least some level of being contained...
2272 *
2273 * In short, if something bad happens, at least we have a choice
2274 * of just killing the apm thread..
2275 */
2276static int __init apm_init(void)
2277{
2278	struct desc_struct *gdt;
2279	int err;
2280
2281	dmi_check_system(apm_dmi_table);
2282
2283	if (apm_info.bios.version == 0 || paravirt_enabled() || machine_is_olpc()) {
2284		printk(KERN_INFO "apm: BIOS not found.\n");
2285		return -ENODEV;
2286	}
2287	printk(KERN_INFO
2288	       "apm: BIOS version %d.%d Flags 0x%02x (Driver version %s)\n",
2289	       ((apm_info.bios.version >> 8) & 0xff),
2290	       (apm_info.bios.version & 0xff),
2291	       apm_info.bios.flags,
2292	       driver_version);
2293	if ((apm_info.bios.flags & APM_32_BIT_SUPPORT) == 0) {
2294		printk(KERN_INFO "apm: no 32 bit BIOS support\n");
2295		return -ENODEV;
2296	}
2297
2298	if (allow_ints)
2299		apm_info.allow_ints = 1;
2300	if (broken_psr)
2301		apm_info.get_power_status_broken = 1;
2302	if (realmode_power_off)
2303		apm_info.realmode_power_off = 1;
2304	/* User can override, but default is to trust DMI */
2305	if (apm_disabled != -1)
2306		apm_info.disabled = apm_disabled;
2307
2308	/*
2309	 * Fix for the Compaq Contura 3/25c which reports BIOS version 0.1
2310	 * but is reportedly a 1.0 BIOS.
2311	 */
2312	if (apm_info.bios.version == 0x001)
2313		apm_info.bios.version = 0x100;
2314
2315	/* BIOS < 1.2 doesn't set cseg_16_len */
2316	if (apm_info.bios.version < 0x102)
2317		apm_info.bios.cseg_16_len = 0; /* 64k */
2318
2319	if (debug) {
2320		printk(KERN_INFO "apm: entry %x:%x cseg16 %x dseg %x",
2321			apm_info.bios.cseg, apm_info.bios.offset,
2322			apm_info.bios.cseg_16, apm_info.bios.dseg);
2323		if (apm_info.bios.version > 0x100)
2324			printk(" cseg len %x, dseg len %x",
2325				apm_info.bios.cseg_len,
2326				apm_info.bios.dseg_len);
2327		if (apm_info.bios.version > 0x101)
2328			printk(" cseg16 len %x", apm_info.bios.cseg_16_len);
2329		printk("\n");
2330	}
2331
2332	if (apm_info.disabled) {
2333		pr_notice("disabled on user request.\n");
2334		return -ENODEV;
2335	}
2336	if ((num_online_cpus() > 1) && !power_off && !smp) {
2337		pr_notice("disabled - APM is not SMP safe.\n");
2338		apm_info.disabled = 1;
2339		return -ENODEV;
2340	}
2341	if (!acpi_disabled) {
2342		pr_notice("overridden by ACPI.\n");
2343		apm_info.disabled = 1;
2344		return -ENODEV;
2345	}
2346
2347	/*
2348	 * Set up the long jump entry point to the APM BIOS, which is called
2349	 * from inline assembly.
2350	 */
2351	apm_bios_entry.offset = apm_info.bios.offset;
2352	apm_bios_entry.segment = APM_CS;
2353
2354	/*
2355	 * The APM 1.1 BIOS is supposed to provide limit information that it
2356	 * recognizes.  Many machines do this correctly, but many others do
2357	 * not restrict themselves to their claimed limit.  When this happens,
2358	 * they will cause a segmentation violation in the kernel at boot time.
2359	 * Most BIOS's, however, will respect a 64k limit, so we use that.
2360	 *
2361	 * Note we only set APM segments on CPU zero, since we pin the APM
2362	 * code to that CPU.
2363	 */
2364	gdt = get_cpu_gdt_table(0);
2365	set_desc_base(&gdt[APM_CS >> 3],
2366		 (unsigned long)__va((unsigned long)apm_info.bios.cseg << 4));
2367	set_desc_base(&gdt[APM_CS_16 >> 3],
2368		 (unsigned long)__va((unsigned long)apm_info.bios.cseg_16 << 4));
2369	set_desc_base(&gdt[APM_DS >> 3],
2370		 (unsigned long)__va((unsigned long)apm_info.bios.dseg << 4));
2371
2372	proc_create("apm", 0, NULL, &apm_file_ops);
2373
2374	kapmd_task = kthread_create(apm, NULL, "kapmd");
2375	if (IS_ERR(kapmd_task)) {
2376		pr_err("disabled - Unable to start kernel thread\n");
2377		err = PTR_ERR(kapmd_task);
2378		kapmd_task = NULL;
2379		remove_proc_entry("apm", NULL);
2380		return err;
2381	}
2382	wake_up_process(kapmd_task);
2383
2384	if (num_online_cpus() > 1 && !smp) {
2385		printk(KERN_NOTICE
2386		       "apm: disabled - APM is not SMP safe (power off active).\n");
2387		return 0;
2388	}
2389
2390	/*
2391	 * Note we don't actually care if the misc_device cannot be registered.
2392	 * this driver can do its job without it, even if userspace can't
2393	 * control it.  just log the error
2394	 */
2395	if (misc_register(&apm_device))
2396		printk(KERN_WARNING "apm: Could not register misc device.\n");
2397
2398	if (HZ != 100)
2399		idle_period = (idle_period * HZ) / 100;
2400	if (idle_threshold < 100) {
2401		if (!cpuidle_register_driver(&apm_idle_driver))
2402			if (cpuidle_register_device(&apm_cpuidle_device))
2403				cpuidle_unregister_driver(&apm_idle_driver);
2404	}
2405
2406	return 0;
2407}
2408
2409static void __exit apm_exit(void)
2410{
2411	int error;
2412
2413	cpuidle_unregister_device(&apm_cpuidle_device);
2414	cpuidle_unregister_driver(&apm_idle_driver);
2415
2416	if (((apm_info.bios.flags & APM_BIOS_DISENGAGED) == 0)
2417	    && (apm_info.connection_version > 0x0100)) {
2418		error = apm_engage_power_management(APM_DEVICE_ALL, 0);
2419		if (error)
2420			apm_error("disengage power management", error);
2421	}
2422	misc_deregister(&apm_device);
2423	remove_proc_entry("apm", NULL);
2424	if (power_off)
2425		pm_power_off = NULL;
2426	if (kapmd_task) {
2427		kthread_stop(kapmd_task);
2428		kapmd_task = NULL;
2429	}
2430}
2431
2432module_init(apm_init);
2433module_exit(apm_exit);
2434
2435MODULE_AUTHOR("Stephen Rothwell");
2436MODULE_DESCRIPTION("Advanced Power Management");
2437MODULE_LICENSE("GPL");
2438module_param(debug, bool, 0644);
2439MODULE_PARM_DESC(debug, "Enable debug mode");
2440module_param(power_off, bool, 0444);
2441MODULE_PARM_DESC(power_off, "Enable power off");
2442module_param(bounce_interval, int, 0444);
2443MODULE_PARM_DESC(bounce_interval,
2444		"Set the number of ticks to ignore suspend bounces");
2445module_param(allow_ints, bool, 0444);
2446MODULE_PARM_DESC(allow_ints, "Allow interrupts during BIOS calls");
2447module_param(broken_psr, bool, 0444);
2448MODULE_PARM_DESC(broken_psr, "BIOS has a broken GetPowerStatus call");
2449module_param(realmode_power_off, bool, 0444);
2450MODULE_PARM_DESC(realmode_power_off,
2451		"Switch to real mode before powering off");
2452module_param(idle_threshold, int, 0444);
2453MODULE_PARM_DESC(idle_threshold,
2454	"System idle percentage above which to make APM BIOS idle calls");
2455module_param(idle_period, int, 0444);
2456MODULE_PARM_DESC(idle_period,
2457	"Period (in sec/100) over which to caculate the idle percentage");
2458module_param(smp, bool, 0444);
2459MODULE_PARM_DESC(smp,
2460	"Set this to enable APM use on an SMP platform. Use with caution on older systems");
2461MODULE_ALIAS_MISCDEV(APM_MINOR_DEV);