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v6.13.7
   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/* -*- linux-c -*-
   3 * APM BIOS driver for Linux
   4 * Copyright 1994-2001 Stephen Rothwell (sfr@canb.auug.org.au)
   5 *
   6 * Initial development of this driver was funded by NEC Australia P/L
   7 *	and NEC Corporation
   8 *
 
 
 
 
 
 
 
 
 
 
   9 * October 1995, Rik Faith (faith@cs.unc.edu):
  10 *    Minor enhancements and updates (to the patch set) for 1.3.x
  11 *    Documentation
  12 * January 1996, Rik Faith (faith@cs.unc.edu):
  13 *    Make /proc/apm easy to format (bump driver version)
  14 * March 1996, Rik Faith (faith@cs.unc.edu):
  15 *    Prohibit APM BIOS calls unless apm_enabled.
  16 *    (Thanks to Ulrich Windl <Ulrich.Windl@rz.uni-regensburg.de>)
  17 * April 1996, Stephen Rothwell (sfr@canb.auug.org.au)
  18 *    Version 1.0 and 1.1
  19 * May 1996, Version 1.2
  20 * Feb 1998, Version 1.3
  21 * Feb 1998, Version 1.4
  22 * Aug 1998, Version 1.5
  23 * Sep 1998, Version 1.6
  24 * Nov 1998, Version 1.7
  25 * Jan 1999, Version 1.8
  26 * Jan 1999, Version 1.9
  27 * Oct 1999, Version 1.10
  28 * Nov 1999, Version 1.11
  29 * Jan 2000, Version 1.12
  30 * Feb 2000, Version 1.13
  31 * Nov 2000, Version 1.14
  32 * Oct 2001, Version 1.15
  33 * Jan 2002, Version 1.16
  34 * Oct 2002, Version 1.16ac
  35 *
  36 * History:
  37 *    0.6b: first version in official kernel, Linux 1.3.46
  38 *    0.7: changed /proc/apm format, Linux 1.3.58
  39 *    0.8: fixed gcc 2.7.[12] compilation problems, Linux 1.3.59
  40 *    0.9: only call bios if bios is present, Linux 1.3.72
  41 *    1.0: use fixed device number, consolidate /proc/apm into this file,
  42 *         Linux 1.3.85
  43 *    1.1: support user-space standby and suspend, power off after system
  44 *         halted, Linux 1.3.98
  45 *    1.2: When resetting RTC after resume, take care so that the time
  46 *         is only incorrect by 30-60mS (vs. 1S previously) (Gabor J. Toth
  47 *         <jtoth@princeton.edu>); improve interaction between
  48 *         screen-blanking and gpm (Stephen Rothwell); Linux 1.99.4
  49 *    1.2a:Simple change to stop mysterious bug reports with SMP also added
  50 *	   levels to the printk calls. APM is not defined for SMP machines.
  51 *         The new replacement for it is, but Linux doesn't yet support this.
  52 *         Alan Cox Linux 2.1.55
  53 *    1.3: Set up a valid data descriptor 0x40 for buggy BIOS's
  54 *    1.4: Upgraded to support APM 1.2. Integrated ThinkPad suspend patch by
  55 *         Dean Gaudet <dgaudet@arctic.org>.
  56 *         C. Scott Ananian <cananian@alumni.princeton.edu> Linux 2.1.87
  57 *    1.5: Fix segment register reloading (in case of bad segments saved
  58 *         across BIOS call).
  59 *         Stephen Rothwell
  60 *    1.6: Cope with compiler/assembler differences.
  61 *         Only try to turn off the first display device.
  62 *         Fix OOPS at power off with no APM BIOS by Jan Echternach
  63 *                   <echter@informatik.uni-rostock.de>
  64 *         Stephen Rothwell
  65 *    1.7: Modify driver's cached copy of the disabled/disengaged flags
  66 *         to reflect current state of APM BIOS.
  67 *         Chris Rankin <rankinc@bellsouth.net>
  68 *         Reset interrupt 0 timer to 100Hz after suspend
  69 *         Chad Miller <cmiller@surfsouth.com>
  70 *         Add CONFIG_APM_IGNORE_SUSPEND_BOUNCE
  71 *         Richard Gooch <rgooch@atnf.csiro.au>
  72 *         Allow boot time disabling of APM
  73 *         Make boot messages far less verbose by default
  74 *         Make asm safer
  75 *         Stephen Rothwell
  76 *    1.8: Add CONFIG_APM_RTC_IS_GMT
  77 *         Richard Gooch <rgooch@atnf.csiro.au>
  78 *         change APM_NOINTS to CONFIG_APM_ALLOW_INTS
  79 *         remove dependency on CONFIG_PROC_FS
  80 *         Stephen Rothwell
  81 *    1.9: Fix small typo.  <laslo@wodip.opole.pl>
  82 *         Try to cope with BIOS's that need to have all display
  83 *         devices blanked and not just the first one.
  84 *         Ross Paterson <ross@soi.city.ac.uk>
  85 *         Fix segment limit setting it has always been wrong as
  86 *         the segments needed to have byte granularity.
  87 *         Mark a few things __init.
  88 *         Add hack to allow power off of SMP systems by popular request.
  89 *         Use CONFIG_SMP instead of __SMP__
  90 *         Ignore BOUNCES for three seconds.
  91 *         Stephen Rothwell
  92 *   1.10: Fix for Thinkpad return code.
  93 *         Merge 2.2 and 2.3 drivers.
  94 *         Remove APM dependencies in arch/i386/kernel/process.c
  95 *         Remove APM dependencies in drivers/char/sysrq.c
  96 *         Reset time across standby.
  97 *         Allow more initialisation on SMP.
  98 *         Remove CONFIG_APM_POWER_OFF and make it boot time
  99 *         configurable (default on).
 100 *         Make debug only a boot time parameter (remove APM_DEBUG).
 101 *         Try to blank all devices on any error.
 102 *   1.11: Remove APM dependencies in drivers/char/console.c
 103 *         Check nr_running to detect if we are idle (from
 104 *         Borislav Deianov <borislav@lix.polytechnique.fr>)
 105 *         Fix for bioses that don't zero the top part of the
 106 *         entrypoint offset (Mario Sitta <sitta@al.unipmn.it>)
 107 *         (reported by Panos Katsaloulis <teras@writeme.com>).
 108 *         Real mode power off patch (Walter Hofmann
 109 *         <Walter.Hofmann@physik.stud.uni-erlangen.de>).
 110 *   1.12: Remove CONFIG_SMP as the compiler will optimize
 111 *         the code away anyway (smp_num_cpus == 1 in UP)
 112 *         noted by Artur Skawina <skawina@geocities.com>.
 113 *         Make power off under SMP work again.
 114 *         Fix thinko with initial engaging of BIOS.
 115 *         Make sure power off only happens on CPU 0
 116 *         (Paul "Rusty" Russell <rusty@rustcorp.com.au>).
 117 *         Do error notification to user mode if BIOS calls fail.
 118 *         Move entrypoint offset fix to ...boot/setup.S
 119 *         where it belongs (Cosmos <gis88564@cis.nctu.edu.tw>).
 120 *         Remove smp-power-off. SMP users must now specify
 121 *         "apm=power-off" on the kernel command line. Suggested
 122 *         by Jim Avera <jima@hal.com>, modified by Alan Cox
 123 *         <alan@lxorguk.ukuu.org.uk>.
 124 *         Register the /proc/apm entry even on SMP so that
 125 *         scripts that check for it before doing power off
 126 *         work (Jim Avera <jima@hal.com>).
 127 *   1.13: Changes for new pm_ interfaces (Andy Henroid
 128 *         <andy_henroid@yahoo.com>).
 129 *         Modularize the code.
 130 *         Fix the Thinkpad (again) :-( (CONFIG_APM_IGNORE_MULTIPLE_SUSPENDS
 131 *         is now the way life works).
 132 *         Fix thinko in suspend() (wrong return).
 133 *         Notify drivers on critical suspend.
 134 *         Make kapmd absorb more idle time (Pavel Machek <pavel@ucw.cz>
 135 *         modified by sfr).
 136 *         Disable interrupts while we are suspended (Andy Henroid
 137 *         <andy_henroid@yahoo.com> fixed by sfr).
 138 *         Make power off work on SMP again (Tony Hoyle
 139 *         <tmh@magenta-logic.com> and <zlatko@iskon.hr>) modified by sfr.
 140 *         Remove CONFIG_APM_SUSPEND_BOUNCE.  The bounce ignore
 141 *         interval is now configurable.
 142 *   1.14: Make connection version persist across module unload/load.
 143 *         Enable and engage power management earlier.
 144 *         Disengage power management on module unload.
 145 *         Changed to use the sysrq-register hack for registering the
 146 *         power off function called by magic sysrq based upon discussions
 147 *         in irc://irc.openprojects.net/#kernelnewbies
 148 *         (Crutcher Dunnavant <crutcher+kernel@datastacks.com>).
 149 *         Make CONFIG_APM_REAL_MODE_POWER_OFF run time configurable.
 150 *         (Arjan van de Ven <arjanv@redhat.com>) modified by sfr.
 151 *         Work around byte swap bug in one of the Vaio's BIOS's
 152 *         (Marc Boucher <marc@mbsi.ca>).
 153 *         Exposed the disable flag to dmi so that we can handle known
 154 *         broken APM (Alan Cox <alan@lxorguk.ukuu.org.uk>).
 155 *   1.14ac: If the BIOS says "I slowed the CPU down" then don't spin
 156 *         calling it - instead idle. (Alan Cox <alan@lxorguk.ukuu.org.uk>)
 157 *         If an APM idle fails log it and idle sensibly
 158 *   1.15: Don't queue events to clients who open the device O_WRONLY.
 159 *         Don't expect replies from clients who open the device O_RDONLY.
 160 *         (Idea from Thomas Hood)
 161 *         Minor waitqueue cleanups. (John Fremlin <chief@bandits.org>)
 162 *   1.16: Fix idle calling. (Andreas Steinmetz <ast@domdv.de> et al.)
 163 *         Notify listeners of standby or suspend events before notifying
 164 *         drivers. Return EBUSY to ioctl() if suspend is rejected.
 165 *         (Russell King <rmk@arm.linux.org.uk> and Thomas Hood)
 166 *         Ignore first resume after we generate our own resume event
 167 *         after a suspend (Thomas Hood)
 168 *         Daemonize now gets rid of our controlling terminal (sfr).
 169 *         CONFIG_APM_CPU_IDLE now just affects the default value of
 170 *         idle_threshold (sfr).
 171 *         Change name of kernel apm daemon (as it no longer idles) (sfr).
 172 *   1.16ac: Fix up SMP support somewhat. You can now force SMP on and we
 173 *	   make _all_ APM calls on the CPU#0. Fix unsafe sign bug.
 174 *	   TODO: determine if its "boot CPU" or "CPU0" we want to lock to.
 175 *
 176 * APM 1.1 Reference:
 177 *
 178 *   Intel Corporation, Microsoft Corporation. Advanced Power Management
 179 *   (APM) BIOS Interface Specification, Revision 1.1, September 1993.
 180 *   Intel Order Number 241704-001.  Microsoft Part Number 781-110-X01.
 181 *
 182 * [This document is available free from Intel by calling 800.628.8686 (fax
 183 * 916.356.6100) or 800.548.4725; or from
 184 * http://www.microsoft.com/whdc/archive/amp_12.mspx  It is also
 185 * available from Microsoft by calling 206.882.8080.]
 186 *
 187 * APM 1.2 Reference:
 188 *   Intel Corporation, Microsoft Corporation. Advanced Power Management
 189 *   (APM) BIOS Interface Specification, Revision 1.2, February 1996.
 190 *
 191 * [This document is available from Microsoft at:
 192 *    http://www.microsoft.com/whdc/archive/amp_12.mspx]
 193 */
 194
 195#define pr_fmt(fmt) "apm: " fmt
 196
 197#include <linux/module.h>
 198
 199#include <linux/poll.h>
 200#include <linux/types.h>
 201#include <linux/stddef.h>
 202#include <linux/timer.h>
 203#include <linux/fcntl.h>
 204#include <linux/slab.h>
 205#include <linux/stat.h>
 206#include <linux/proc_fs.h>
 207#include <linux/seq_file.h>
 208#include <linux/miscdevice.h>
 209#include <linux/apm_bios.h>
 210#include <linux/init.h>
 211#include <linux/time.h>
 212#include <linux/sched/signal.h>
 213#include <linux/sched/cputime.h>
 214#include <linux/pm.h>
 215#include <linux/capability.h>
 216#include <linux/device.h>
 217#include <linux/kernel.h>
 218#include <linux/freezer.h>
 219#include <linux/smp.h>
 220#include <linux/dmi.h>
 221#include <linux/suspend.h>
 222#include <linux/kthread.h>
 223#include <linux/jiffies.h>
 224#include <linux/acpi.h>
 225#include <linux/syscore_ops.h>
 226#include <linux/i8253.h>
 227#include <linux/cpuidle.h>
 228
 229#include <linux/uaccess.h>
 230#include <asm/desc.h>
 231#include <asm/olpc.h>
 232#include <asm/paravirt.h>
 233#include <asm/reboot.h>
 234#include <asm/nospec-branch.h>
 235#include <asm/ibt.h>
 236
 237#if defined(CONFIG_APM_DISPLAY_BLANK) && defined(CONFIG_VT)
 238extern int (*console_blank_hook)(int);
 239#endif
 240
 241/*
 
 
 
 
 
 
 242 * Various options can be changed at boot time as follows:
 243 * (We allow underscores for compatibility with the modules code)
 244 *	apm=on/off			enable/disable APM
 245 *	    [no-]allow[-_]ints		allow interrupts during BIOS calls
 246 *	    [no-]broken[-_]psr		BIOS has a broken GetPowerStatus call
 247 *	    [no-]realmode[-_]power[-_]off	switch to real mode before
 248 *	    					powering off
 249 *	    [no-]debug			log some debugging messages
 250 *	    [no-]power[-_]off		power off on shutdown
 251 *	    [no-]smp			Use apm even on an SMP box
 252 *	    bounce[-_]interval=<n>	number of ticks to ignore suspend
 253 *	    				bounces
 254 *          idle[-_]threshold=<n>       System idle percentage above which to
 255 *                                      make APM BIOS idle calls. Set it to
 256 *                                      100 to disable.
 257 *          idle[-_]period=<n>          Period (in 1/100s of a second) over
 258 *                                      which the idle percentage is
 259 *                                      calculated.
 260 */
 261
 262/* KNOWN PROBLEM MACHINES:
 263 *
 264 * U: TI 4000M TravelMate: BIOS is *NOT* APM compliant
 265 *                         [Confirmed by TI representative]
 266 * ?: ACER 486DX4/75: uses dseg 0040, in violation of APM specification
 267 *                    [Confirmed by BIOS disassembly]
 268 *                    [This may work now ...]
 269 * P: Toshiba 1950S: battery life information only gets updated after resume
 270 * P: Midwest Micro Soundbook Elite DX2/66 monochrome: screen blanking
 271 * 	broken in BIOS [Reported by Garst R. Reese <reese@isn.net>]
 272 * ?: AcerNote-950: oops on reading /proc/apm - workaround is a WIP
 273 * 	Neale Banks <neale@lowendale.com.au> December 2000
 274 *
 275 * Legend: U = unusable with APM patches
 276 *         P = partially usable with APM patches
 277 */
 278
 279/*
 280 * Define as 1 to make the driver always call the APM BIOS busy
 281 * routine even if the clock was not reported as slowed by the
 282 * idle routine.  Otherwise, define as 0.
 283 */
 284#define ALWAYS_CALL_BUSY   1
 285
 286/*
 287 * Define to make the APM BIOS calls zero all data segment registers (so
 288 * that an incorrect BIOS implementation will cause a kernel panic if it
 289 * tries to write to arbitrary memory).
 290 */
 291#define APM_ZERO_SEGS
 292
 293#include <asm/apm.h>
 294
 295/*
 296 * Define to re-initialize the interrupt 0 timer to 100 Hz after a suspend.
 297 * This patched by Chad Miller <cmiller@surfsouth.com>, original code by
 298 * David Chen <chen@ctpa04.mit.edu>
 299 */
 300#undef INIT_TIMER_AFTER_SUSPEND
 301
 302#ifdef INIT_TIMER_AFTER_SUSPEND
 303#include <linux/timex.h>
 304#include <asm/io.h>
 305#include <linux/delay.h>
 306#endif
 307
 308/*
 309 * Need to poll the APM BIOS every second
 310 */
 311#define APM_CHECK_TIMEOUT	(HZ)
 312
 313/*
 314 * Ignore suspend events for this amount of time after a resume
 315 */
 316#define DEFAULT_BOUNCE_INTERVAL	(3 * HZ)
 317
 318/*
 319 * Maximum number of events stored
 320 */
 321#define APM_MAX_EVENTS		20
 322
 323/*
 324 * The per-file APM data
 325 */
 326struct apm_user {
 327	int		magic;
 328	struct apm_user *next;
 329	unsigned int	suser: 1;
 330	unsigned int	writer: 1;
 331	unsigned int	reader: 1;
 332	unsigned int	suspend_wait: 1;
 333	int		suspend_result;
 334	int		suspends_pending;
 335	int		standbys_pending;
 336	int		suspends_read;
 337	int		standbys_read;
 338	int		event_head;
 339	int		event_tail;
 340	apm_event_t	events[APM_MAX_EVENTS];
 341};
 342
 343/*
 344 * The magic number in apm_user
 345 */
 346#define APM_BIOS_MAGIC		0x4101
 347
 348/*
 349 * idle percentage above which bios idle calls are done
 350 */
 351#ifdef CONFIG_APM_CPU_IDLE
 352#define DEFAULT_IDLE_THRESHOLD	95
 353#else
 354#define DEFAULT_IDLE_THRESHOLD	100
 355#endif
 356#define DEFAULT_IDLE_PERIOD	(100 / 3)
 357
 358static int apm_cpu_idle(struct cpuidle_device *dev,
 359			struct cpuidle_driver *drv, int index);
 360
 361static struct cpuidle_driver apm_idle_driver = {
 362	.name = "apm_idle",
 363	.owner = THIS_MODULE,
 364	.states = {
 365		{ /* entry 0 is for polling */ },
 366		{ /* entry 1 is for APM idle */
 367			.name = "APM",
 368			.desc = "APM idle",
 
 369			.exit_latency = 250,	/* WAG */
 370			.target_residency = 500,	/* WAG */
 371			.enter = &apm_cpu_idle
 372		},
 373	},
 374	.state_count = 2,
 375};
 376
 377static struct cpuidle_device apm_cpuidle_device;
 378
 379/*
 380 * Local variables
 381 */
 382__visible struct {
 383	unsigned long	offset;
 384	unsigned short	segment;
 385} apm_bios_entry;
 386static int clock_slowed;
 387static int idle_threshold __read_mostly = DEFAULT_IDLE_THRESHOLD;
 388static int idle_period __read_mostly = DEFAULT_IDLE_PERIOD;
 389static int suspends_pending;
 390static int standbys_pending;
 391static int ignore_sys_suspend;
 392static int ignore_normal_resume;
 393static int bounce_interval __read_mostly = DEFAULT_BOUNCE_INTERVAL;
 394
 395static bool debug __read_mostly;
 396static bool smp __read_mostly;
 397static int apm_disabled = -1;
 398#ifdef CONFIG_SMP
 399static bool power_off;
 400#else
 401static bool power_off = 1;
 402#endif
 403static bool realmode_power_off;
 404#ifdef CONFIG_APM_ALLOW_INTS
 405static bool allow_ints = 1;
 406#else
 407static bool allow_ints;
 408#endif
 409static bool broken_psr;
 410
 411static DECLARE_WAIT_QUEUE_HEAD(apm_waitqueue);
 412static DECLARE_WAIT_QUEUE_HEAD(apm_suspend_waitqueue);
 413static struct apm_user *user_list;
 414static DEFINE_SPINLOCK(user_list_lock);
 415static DEFINE_MUTEX(apm_mutex);
 416
 417/*
 418 * Set up a segment that references the real mode segment 0x40
 419 * that extends up to the end of page zero (that we have reserved).
 420 * This is for buggy BIOS's that refer to (real mode) segment 0x40
 421 * even though they are called in protected mode.
 422 */
 423static struct desc_struct bad_bios_desc = GDT_ENTRY_INIT(DESC_DATA32_BIOS,
 424			(unsigned long)__va(0x400UL), PAGE_SIZE - 0x400 - 1);
 425
 426static const char driver_version[] = "1.16ac";	/* no spaces */
 427
 428static struct task_struct *kapmd_task;
 429
 430/*
 431 *	APM event names taken from the APM 1.2 specification. These are
 432 *	the message codes that the BIOS uses to tell us about events
 433 */
 434static const char * const apm_event_name[] = {
 435	"system standby",
 436	"system suspend",
 437	"normal resume",
 438	"critical resume",
 439	"low battery",
 440	"power status change",
 441	"update time",
 442	"critical suspend",
 443	"user standby",
 444	"user suspend",
 445	"system standby resume",
 446	"capabilities change"
 447};
 448#define NR_APM_EVENT_NAME ARRAY_SIZE(apm_event_name)
 449
 450typedef struct lookup_t {
 451	int	key;
 452	char 	*msg;
 453} lookup_t;
 454
 455/*
 456 *	The BIOS returns a set of standard error codes in AX when the
 457 *	carry flag is set.
 458 */
 459
 460static const lookup_t error_table[] = {
 461/* N/A	{ APM_SUCCESS,		"Operation succeeded" }, */
 462	{ APM_DISABLED,		"Power management disabled" },
 463	{ APM_CONNECTED,	"Real mode interface already connected" },
 464	{ APM_NOT_CONNECTED,	"Interface not connected" },
 465	{ APM_16_CONNECTED,	"16 bit interface already connected" },
 466/* N/A	{ APM_16_UNSUPPORTED,	"16 bit interface not supported" }, */
 467	{ APM_32_CONNECTED,	"32 bit interface already connected" },
 468	{ APM_32_UNSUPPORTED,	"32 bit interface not supported" },
 469	{ APM_BAD_DEVICE,	"Unrecognized device ID" },
 470	{ APM_BAD_PARAM,	"Parameter out of range" },
 471	{ APM_NOT_ENGAGED,	"Interface not engaged" },
 472	{ APM_BAD_FUNCTION,     "Function not supported" },
 473	{ APM_RESUME_DISABLED,	"Resume timer disabled" },
 474	{ APM_BAD_STATE,	"Unable to enter requested state" },
 475/* N/A	{ APM_NO_EVENTS,	"No events pending" }, */
 476	{ APM_NO_ERROR,		"BIOS did not set a return code" },
 477	{ APM_NOT_PRESENT,	"No APM present" }
 478};
 479#define ERROR_COUNT	ARRAY_SIZE(error_table)
 480
 481/**
 482 *	apm_error	-	display an APM error
 483 *	@str: information string
 484 *	@err: APM BIOS return code
 485 *
 486 *	Write a meaningful log entry to the kernel log in the event of
 487 *	an APM error.  Note that this also handles (negative) kernel errors.
 488 */
 489
 490static void apm_error(char *str, int err)
 491{
 492	int i;
 493
 494	for (i = 0; i < ERROR_COUNT; i++)
 495		if (error_table[i].key == err)
 496			break;
 497	if (i < ERROR_COUNT)
 498		pr_notice("%s: %s\n", str, error_table[i].msg);
 499	else if (err < 0)
 500		pr_notice("%s: linux error code %i\n", str, err);
 501	else
 502		pr_notice("%s: unknown error code %#2.2x\n",
 503		       str, err);
 504}
 505
 506/*
 507 * These are the actual BIOS calls.  Depending on APM_ZERO_SEGS and
 508 * apm_info.allow_ints, we are being really paranoid here!  Not only
 509 * are interrupts disabled, but all the segment registers (except SS)
 510 * are saved and zeroed this means that if the BIOS tries to reference
 511 * any data without explicitly loading the segment registers, the kernel
 512 * will fault immediately rather than have some unforeseen circumstances
 513 * for the rest of the kernel.  And it will be very obvious!  :-) Doing
 514 * this depends on CS referring to the same physical memory as DS so that
 515 * DS can be zeroed before the call. Unfortunately, we can't do anything
 516 * about the stack segment/pointer.  Also, we tell the compiler that
 517 * everything could change.
 518 *
 519 * Also, we KNOW that for the non error case of apm_bios_call, there
 520 * is no useful data returned in the low order 8 bits of eax.
 521 */
 522
 523static inline unsigned long __apm_irq_save(void)
 524{
 525	unsigned long flags;
 526	local_save_flags(flags);
 527	if (apm_info.allow_ints) {
 528		if (irqs_disabled_flags(flags))
 529			local_irq_enable();
 530	} else
 531		local_irq_disable();
 532
 533	return flags;
 534}
 535
 536#define apm_irq_save(flags) \
 537	do { flags = __apm_irq_save(); } while (0)
 538
 539static inline void apm_irq_restore(unsigned long flags)
 540{
 541	if (irqs_disabled_flags(flags))
 542		local_irq_disable();
 543	else if (irqs_disabled())
 544		local_irq_enable();
 545}
 546
 547#ifdef APM_ZERO_SEGS
 548#	define APM_DECL_SEGS \
 549		unsigned int saved_fs; unsigned int saved_gs;
 550#	define APM_DO_SAVE_SEGS \
 551		savesegment(fs, saved_fs); savesegment(gs, saved_gs)
 552#	define APM_DO_RESTORE_SEGS \
 553		loadsegment(fs, saved_fs); loadsegment(gs, saved_gs)
 554#else
 555#	define APM_DECL_SEGS
 556#	define APM_DO_SAVE_SEGS
 557#	define APM_DO_RESTORE_SEGS
 558#endif
 559
 560struct apm_bios_call {
 561	u32 func;
 562	/* In and out */
 563	u32 ebx;
 564	u32 ecx;
 565	/* Out only */
 566	u32 eax;
 567	u32 edx;
 568	u32 esi;
 569
 570	/* Error: -ENOMEM, or bits 8-15 of eax */
 571	int err;
 572};
 573
 574/**
 575 *	__apm_bios_call - Make an APM BIOS 32bit call
 576 *	@_call: pointer to struct apm_bios_call.
 577 *
 578 *	Make an APM call using the 32bit protected mode interface. The
 579 *	caller is responsible for knowing if APM BIOS is configured and
 580 *	enabled. This call can disable interrupts for a long period of
 581 *	time on some laptops.  The return value is in AH and the carry
 582 *	flag is loaded into AL.  If there is an error, then the error
 583 *	code is returned in AH (bits 8-15 of eax) and this function
 584 *	returns non-zero.
 585 *
 586 *	Note: this makes the call on the current CPU.
 587 */
 588static long __apm_bios_call(void *_call)
 589{
 590	APM_DECL_SEGS
 591	unsigned long		flags;
 592	int			cpu;
 593	struct desc_struct	save_desc_40;
 594	struct desc_struct	*gdt;
 595	struct apm_bios_call	*call = _call;
 596	u64			ibt;
 597
 598	cpu = get_cpu();
 599	BUG_ON(cpu != 0);
 600	gdt = get_cpu_gdt_rw(cpu);
 601	save_desc_40 = gdt[0x40 / 8];
 602	gdt[0x40 / 8] = bad_bios_desc;
 603
 604	apm_irq_save(flags);
 605	firmware_restrict_branch_speculation_start();
 606	ibt = ibt_save(true);
 607	APM_DO_SAVE_SEGS;
 608	apm_bios_call_asm(call->func, call->ebx, call->ecx,
 609			  &call->eax, &call->ebx, &call->ecx, &call->edx,
 610			  &call->esi);
 611	APM_DO_RESTORE_SEGS;
 612	ibt_restore(ibt);
 613	firmware_restrict_branch_speculation_end();
 614	apm_irq_restore(flags);
 615	gdt[0x40 / 8] = save_desc_40;
 616	put_cpu();
 617
 618	return call->eax & 0xff;
 619}
 620
 621/* Run __apm_bios_call or __apm_bios_call_simple on CPU 0 */
 622static int on_cpu0(long (*fn)(void *), struct apm_bios_call *call)
 623{
 624	int ret;
 625
 626	/* Don't bother with work_on_cpu in the common case, so we don't
 627	 * have to worry about OOM or overhead. */
 628	if (get_cpu() == 0) {
 629		ret = fn(call);
 630		put_cpu();
 631	} else {
 632		put_cpu();
 633		ret = work_on_cpu(0, fn, call);
 634	}
 635
 636	/* work_on_cpu can fail with -ENOMEM */
 637	if (ret < 0)
 638		call->err = ret;
 639	else
 640		call->err = (call->eax >> 8) & 0xff;
 641
 642	return ret;
 643}
 644
 645/**
 646 *	apm_bios_call	-	Make an APM BIOS 32bit call (on CPU 0)
 647 *	@call: the apm_bios_call registers.
 648 *
 649 *	If there is an error, it is returned in @call.err.
 650 */
 651static int apm_bios_call(struct apm_bios_call *call)
 652{
 653	return on_cpu0(__apm_bios_call, call);
 654}
 655
 656/**
 657 *	__apm_bios_call_simple - Make an APM BIOS 32bit call (on CPU 0)
 658 *	@_call: pointer to struct apm_bios_call.
 659 *
 660 *	Make a BIOS call that returns one value only, or just status.
 661 *	If there is an error, then the error code is returned in AH
 662 *	(bits 8-15 of eax) and this function returns non-zero (it can
 663 *	also return -ENOMEM). This is used for simpler BIOS operations.
 664 *	This call may hold interrupts off for a long time on some laptops.
 665 *
 666 *	Note: this makes the call on the current CPU.
 667 */
 668static long __apm_bios_call_simple(void *_call)
 669{
 670	u8			error;
 671	APM_DECL_SEGS
 672	unsigned long		flags;
 673	int			cpu;
 674	struct desc_struct	save_desc_40;
 675	struct desc_struct	*gdt;
 676	struct apm_bios_call	*call = _call;
 677	u64			ibt;
 678
 679	cpu = get_cpu();
 680	BUG_ON(cpu != 0);
 681	gdt = get_cpu_gdt_rw(cpu);
 682	save_desc_40 = gdt[0x40 / 8];
 683	gdt[0x40 / 8] = bad_bios_desc;
 684
 685	apm_irq_save(flags);
 686	firmware_restrict_branch_speculation_start();
 687	ibt = ibt_save(true);
 688	APM_DO_SAVE_SEGS;
 689	error = apm_bios_call_simple_asm(call->func, call->ebx, call->ecx,
 690					 &call->eax);
 691	APM_DO_RESTORE_SEGS;
 692	ibt_restore(ibt);
 693	firmware_restrict_branch_speculation_end();
 694	apm_irq_restore(flags);
 695	gdt[0x40 / 8] = save_desc_40;
 696	put_cpu();
 697	return error;
 698}
 699
 700/**
 701 *	apm_bios_call_simple	-	make a simple APM BIOS 32bit call
 702 *	@func: APM function to invoke
 703 *	@ebx_in: EBX register value for BIOS call
 704 *	@ecx_in: ECX register value for BIOS call
 705 *	@eax: EAX register on return from the BIOS call
 706 *	@err: bits
 707 *
 708 *	Make a BIOS call that returns one value only, or just status.
 709 *	If there is an error, then the error code is returned in @err
 710 *	and this function returns non-zero. This is used for simpler
 711 *	BIOS operations.  This call may hold interrupts off for a long
 712 *	time on some laptops.
 713 */
 714static int apm_bios_call_simple(u32 func, u32 ebx_in, u32 ecx_in, u32 *eax,
 715				int *err)
 716{
 717	struct apm_bios_call call;
 718	int ret;
 719
 720	call.func = func;
 721	call.ebx = ebx_in;
 722	call.ecx = ecx_in;
 723
 724	ret = on_cpu0(__apm_bios_call_simple, &call);
 725	*eax = call.eax;
 726	*err = call.err;
 727	return ret;
 728}
 729
 730/**
 731 *	apm_driver_version	-	APM driver version
 732 *	@val:	loaded with the APM version on return
 733 *
 734 *	Retrieve the APM version supported by the BIOS. This is only
 735 *	supported for APM 1.1 or higher. An error indicates APM 1.0 is
 736 *	probably present.
 737 *
 738 *	On entry val should point to a value indicating the APM driver
 739 *	version with the high byte being the major and the low byte the
 740 *	minor number both in BCD
 741 *
 742 *	On return it will hold the BIOS revision supported in the
 743 *	same format.
 744 */
 745
 746static int apm_driver_version(u_short *val)
 747{
 748	u32 eax;
 749	int err;
 750
 751	if (apm_bios_call_simple(APM_FUNC_VERSION, 0, *val, &eax, &err))
 752		return err;
 753	*val = eax;
 754	return APM_SUCCESS;
 755}
 756
 757/**
 758 *	apm_get_event	-	get an APM event from the BIOS
 759 *	@event: pointer to the event
 760 *	@info: point to the event information
 761 *
 762 *	The APM BIOS provides a polled information for event
 763 *	reporting. The BIOS expects to be polled at least every second
 764 *	when events are pending. When a message is found the caller should
 765 *	poll until no more messages are present.  However, this causes
 766 *	problems on some laptops where a suspend event notification is
 767 *	not cleared until it is acknowledged.
 768 *
 769 *	Additional information is returned in the info pointer, providing
 770 *	that APM 1.2 is in use. If no messages are pending the value 0x80
 771 *	is returned (No power management events pending).
 772 */
 773static int apm_get_event(apm_event_t *event, apm_eventinfo_t *info)
 774{
 775	struct apm_bios_call call;
 776
 777	call.func = APM_FUNC_GET_EVENT;
 778	call.ebx = call.ecx = 0;
 779
 780	if (apm_bios_call(&call))
 781		return call.err;
 782
 783	*event = call.ebx;
 784	if (apm_info.connection_version < 0x0102)
 785		*info = ~0; /* indicate info not valid */
 786	else
 787		*info = call.ecx;
 788	return APM_SUCCESS;
 789}
 790
 791/**
 792 *	set_power_state	-	set the power management state
 793 *	@what: which items to transition
 794 *	@state: state to transition to
 795 *
 796 *	Request an APM change of state for one or more system devices. The
 797 *	processor state must be transitioned last of all. what holds the
 798 *	class of device in the upper byte and the device number (0xFF for
 799 *	all) for the object to be transitioned.
 800 *
 801 *	The state holds the state to transition to, which may in fact
 802 *	be an acceptance of a BIOS requested state change.
 803 */
 804
 805static int set_power_state(u_short what, u_short state)
 806{
 807	u32 eax;
 808	int err;
 809
 810	if (apm_bios_call_simple(APM_FUNC_SET_STATE, what, state, &eax, &err))
 811		return err;
 812	return APM_SUCCESS;
 813}
 814
 815/**
 816 *	set_system_power_state - set system wide power state
 817 *	@state: which state to enter
 818 *
 819 *	Transition the entire system into a new APM power state.
 820 */
 821
 822static int set_system_power_state(u_short state)
 823{
 824	return set_power_state(APM_DEVICE_ALL, state);
 825}
 826
 827/**
 828 *	apm_do_idle	-	perform power saving
 829 *
 830 *	This function notifies the BIOS that the processor is (in the view
 831 *	of the OS) idle. It returns -1 in the event that the BIOS refuses
 832 *	to handle the idle request. On a success the function returns 1
 833 *	if the BIOS did clock slowing or 0 otherwise.
 834 */
 835
 836static int apm_do_idle(void)
 837{
 838	u32 eax;
 839	u8 ret = 0;
 840	int idled = 0;
 
 841	int err = 0;
 842
 
 
 
 
 
 
 
 
 
 843	if (!need_resched()) {
 844		idled = 1;
 845		ret = apm_bios_call_simple(APM_FUNC_IDLE, 0, 0, &eax, &err);
 846	}
 
 
 847
 848	if (!idled)
 849		return 0;
 850
 851	if (ret) {
 852		static unsigned long t;
 853
 854		/* This always fails on some SMP boards running UP kernels.
 855		 * Only report the failure the first 5 times.
 856		 */
 857		if (++t < 5) {
 858			printk(KERN_DEBUG "apm_do_idle failed (%d)\n", err);
 859			t = jiffies;
 860		}
 861		return -1;
 862	}
 863	clock_slowed = (apm_info.bios.flags & APM_IDLE_SLOWS_CLOCK) != 0;
 864	return clock_slowed;
 865}
 866
 867/**
 868 *	apm_do_busy	-	inform the BIOS the CPU is busy
 869 *
 870 *	Request that the BIOS brings the CPU back to full performance.
 871 */
 872
 873static void apm_do_busy(void)
 874{
 875	u32 dummy;
 876	int err;
 877
 878	if (clock_slowed || ALWAYS_CALL_BUSY) {
 879		(void)apm_bios_call_simple(APM_FUNC_BUSY, 0, 0, &dummy, &err);
 880		clock_slowed = 0;
 881	}
 882}
 883
 884/*
 885 * If no process has really been interested in
 886 * the CPU for some time, we want to call BIOS
 887 * power management - we probably want
 888 * to conserve power.
 889 */
 890#define IDLE_CALC_LIMIT	(HZ * 100)
 891#define IDLE_LEAKY_MAX	16
 892
 893/**
 894 * apm_cpu_idle		-	cpu idling for APM capable Linux
 895 *
 896 * This is the idling function the kernel executes when APM is available. It
 897 * tries to do BIOS powermanagement based on the average system idle time.
 898 * Furthermore it calls the system default idle routine.
 899 */
 900
 901static int apm_cpu_idle(struct cpuidle_device *dev,
 902	struct cpuidle_driver *drv, int index)
 903{
 904	static int use_apm_idle; /* = 0 */
 905	static unsigned int last_jiffies; /* = 0 */
 906	static u64 last_stime; /* = 0 */
 907	u64 stime, utime;
 908
 909	int apm_idle_done = 0;
 910	unsigned int jiffies_since_last_check = jiffies - last_jiffies;
 911	unsigned int bucket;
 912
 913recalc:
 914	task_cputime(current, &utime, &stime);
 915	if (jiffies_since_last_check > IDLE_CALC_LIMIT) {
 916		use_apm_idle = 0;
 917	} else if (jiffies_since_last_check > idle_period) {
 918		unsigned int idle_percentage;
 919
 920		idle_percentage = nsecs_to_jiffies(stime - last_stime);
 921		idle_percentage *= 100;
 922		idle_percentage /= jiffies_since_last_check;
 923		use_apm_idle = (idle_percentage > idle_threshold);
 924		if (apm_info.forbid_idle)
 925			use_apm_idle = 0;
 926	}
 927
 928	last_jiffies = jiffies;
 929	last_stime = stime;
 930
 931	bucket = IDLE_LEAKY_MAX;
 932
 933	while (!need_resched()) {
 934		if (use_apm_idle) {
 935			unsigned int t;
 936
 937			t = jiffies;
 938			switch (apm_do_idle()) {
 939			case 0:
 940				apm_idle_done = 1;
 941				if (t != jiffies) {
 942					if (bucket) {
 943						bucket = IDLE_LEAKY_MAX;
 944						continue;
 945					}
 946				} else if (bucket) {
 947					bucket--;
 948					continue;
 949				}
 950				break;
 951			case 1:
 952				apm_idle_done = 1;
 953				break;
 954			default: /* BIOS refused */
 955				break;
 956			}
 957		}
 958		default_idle();
 959		local_irq_disable();
 960		jiffies_since_last_check = jiffies - last_jiffies;
 961		if (jiffies_since_last_check > idle_period)
 962			goto recalc;
 963	}
 964
 965	if (apm_idle_done)
 966		apm_do_busy();
 967
 968	return index;
 969}
 970
 971/**
 972 *	apm_power_off	-	ask the BIOS to power off
 973 *
 974 *	Handle the power off sequence. This is the one piece of code we
 975 *	will execute even on SMP machines. In order to deal with BIOS
 976 *	bugs we support real mode APM BIOS power off calls. We also make
 977 *	the SMP call on CPU0 as some systems will only honour this call
 978 *	on their first cpu.
 979 */
 980
 981static void apm_power_off(void)
 982{
 983	/* Some bioses don't like being called from CPU != 0 */
 984	if (apm_info.realmode_power_off) {
 985		set_cpus_allowed_ptr(current, cpumask_of(0));
 986		machine_real_restart(MRR_APM);
 987	} else {
 988		(void)set_system_power_state(APM_STATE_OFF);
 989	}
 990}
 991
 992#ifdef CONFIG_APM_DO_ENABLE
 993
 994/**
 995 *	apm_enable_power_management - enable BIOS APM power management
 996 *	@enable: enable yes/no
 997 *
 998 *	Enable or disable the APM BIOS power services.
 999 */
1000
1001static int apm_enable_power_management(int enable)
1002{
1003	u32 eax;
1004	int err;
1005
1006	if ((enable == 0) && (apm_info.bios.flags & APM_BIOS_DISENGAGED))
1007		return APM_NOT_ENGAGED;
1008	if (apm_bios_call_simple(APM_FUNC_ENABLE_PM, APM_DEVICE_BALL,
1009				 enable, &eax, &err))
1010		return err;
1011	if (enable)
1012		apm_info.bios.flags &= ~APM_BIOS_DISABLED;
1013	else
1014		apm_info.bios.flags |= APM_BIOS_DISABLED;
1015	return APM_SUCCESS;
1016}
1017#endif
1018
1019/**
1020 *	apm_get_power_status	-	get current power state
1021 *	@status: returned status
1022 *	@bat: battery info
1023 *	@life: estimated life
1024 *
1025 *	Obtain the current power status from the APM BIOS. We return a
1026 *	status which gives the rough battery status, and current power
1027 *	source. The bat value returned give an estimate as a percentage
1028 *	of life and a status value for the battery. The estimated life
1029 *	if reported is a lifetime in seconds/minutes at current power
1030 *	consumption.
1031 */
1032
1033static int apm_get_power_status(u_short *status, u_short *bat, u_short *life)
1034{
1035	struct apm_bios_call call;
1036
1037	call.func = APM_FUNC_GET_STATUS;
1038	call.ebx = APM_DEVICE_ALL;
1039	call.ecx = 0;
1040
1041	if (apm_info.get_power_status_broken)
1042		return APM_32_UNSUPPORTED;
1043	if (apm_bios_call(&call)) {
1044		if (!call.err)
1045			return APM_NO_ERROR;
1046		return call.err;
1047	}
1048	*status = call.ebx;
1049	*bat = call.ecx;
1050	if (apm_info.get_power_status_swabinminutes) {
1051		*life = swab16((u16)call.edx);
1052		*life |= 0x8000;
1053	} else
1054		*life = call.edx;
1055	return APM_SUCCESS;
1056}
1057
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1058/**
1059 *	apm_engage_power_management	-	enable PM on a device
1060 *	@device: identity of device
1061 *	@enable: on/off
1062 *
1063 *	Activate or deactivate power management on either a specific device
1064 *	or the entire system (%APM_DEVICE_ALL).
1065 */
1066
1067static int apm_engage_power_management(u_short device, int enable)
1068{
1069	u32 eax;
1070	int err;
1071
1072	if ((enable == 0) && (device == APM_DEVICE_ALL)
1073	    && (apm_info.bios.flags & APM_BIOS_DISABLED))
1074		return APM_DISABLED;
1075	if (apm_bios_call_simple(APM_FUNC_ENGAGE_PM, device, enable,
1076				 &eax, &err))
1077		return err;
1078	if (device == APM_DEVICE_ALL) {
1079		if (enable)
1080			apm_info.bios.flags &= ~APM_BIOS_DISENGAGED;
1081		else
1082			apm_info.bios.flags |= APM_BIOS_DISENGAGED;
1083	}
1084	return APM_SUCCESS;
1085}
1086
1087#if defined(CONFIG_APM_DISPLAY_BLANK) && defined(CONFIG_VT)
1088
1089/**
1090 *	apm_console_blank	-	blank the display
1091 *	@blank: on/off
1092 *
1093 *	Attempt to blank the console, firstly by blanking just video device
1094 *	zero, and if that fails (some BIOSes don't support it) then it blanks
1095 *	all video devices. Typically the BIOS will do laptop backlight and
1096 *	monitor powerdown for us.
1097 */
1098
1099static int apm_console_blank(int blank)
1100{
1101	int error = APM_NOT_ENGAGED; /* silence gcc */
1102	int i;
1103	u_short state;
1104	static const u_short dev[3] = { 0x100, 0x1FF, 0x101 };
1105
1106	state = blank ? APM_STATE_STANDBY : APM_STATE_READY;
1107
1108	for (i = 0; i < ARRAY_SIZE(dev); i++) {
1109		error = set_power_state(dev[i], state);
1110
1111		if ((error == APM_SUCCESS) || (error == APM_NO_ERROR))
1112			return 1;
1113
1114		if (error == APM_NOT_ENGAGED)
1115			break;
1116	}
1117
1118	if (error == APM_NOT_ENGAGED) {
1119		static int tried;
1120		int eng_error;
1121		if (tried++ == 0) {
1122			eng_error = apm_engage_power_management(APM_DEVICE_ALL, 1);
1123			if (eng_error) {
1124				apm_error("set display", error);
1125				apm_error("engage interface", eng_error);
1126				return 0;
1127			} else
1128				return apm_console_blank(blank);
1129		}
1130	}
1131	apm_error("set display", error);
1132	return 0;
1133}
1134#endif
1135
1136static int queue_empty(struct apm_user *as)
1137{
1138	return as->event_head == as->event_tail;
1139}
1140
1141static apm_event_t get_queued_event(struct apm_user *as)
1142{
1143	if (++as->event_tail >= APM_MAX_EVENTS)
1144		as->event_tail = 0;
1145	return as->events[as->event_tail];
1146}
1147
1148static void queue_event(apm_event_t event, struct apm_user *sender)
1149{
1150	struct apm_user *as;
1151
1152	spin_lock(&user_list_lock);
1153	if (user_list == NULL)
1154		goto out;
1155	for (as = user_list; as != NULL; as = as->next) {
1156		if ((as == sender) || (!as->reader))
1157			continue;
1158		if (++as->event_head >= APM_MAX_EVENTS)
1159			as->event_head = 0;
1160
1161		if (as->event_head == as->event_tail) {
1162			static int notified;
1163
1164			if (notified++ == 0)
1165				pr_err("an event queue overflowed\n");
1166			if (++as->event_tail >= APM_MAX_EVENTS)
1167				as->event_tail = 0;
1168		}
1169		as->events[as->event_head] = event;
1170		if (!as->suser || !as->writer)
1171			continue;
1172		switch (event) {
1173		case APM_SYS_SUSPEND:
1174		case APM_USER_SUSPEND:
1175			as->suspends_pending++;
1176			suspends_pending++;
1177			break;
1178
1179		case APM_SYS_STANDBY:
1180		case APM_USER_STANDBY:
1181			as->standbys_pending++;
1182			standbys_pending++;
1183			break;
1184		}
1185	}
1186	wake_up_interruptible(&apm_waitqueue);
1187out:
1188	spin_unlock(&user_list_lock);
1189}
1190
1191static void reinit_timer(void)
1192{
1193#ifdef INIT_TIMER_AFTER_SUSPEND
1194	unsigned long flags;
1195
1196	raw_spin_lock_irqsave(&i8253_lock, flags);
1197	/* set the clock to HZ */
1198	outb_p(0x34, PIT_MODE);		/* binary, mode 2, LSB/MSB, ch 0 */
1199	udelay(10);
1200	outb_p(LATCH & 0xff, PIT_CH0);	/* LSB */
1201	udelay(10);
1202	outb_p(LATCH >> 8, PIT_CH0);	/* MSB */
1203	udelay(10);
1204	raw_spin_unlock_irqrestore(&i8253_lock, flags);
1205#endif
1206}
1207
1208static int suspend(int vetoable)
1209{
1210	int err;
1211	struct apm_user	*as;
1212
1213	dpm_suspend_start(PMSG_SUSPEND);
1214	dpm_suspend_end(PMSG_SUSPEND);
1215
1216	local_irq_disable();
1217	syscore_suspend();
1218
1219	local_irq_enable();
1220
1221	save_processor_state();
1222	err = set_system_power_state(APM_STATE_SUSPEND);
1223	ignore_normal_resume = 1;
1224	restore_processor_state();
1225
1226	local_irq_disable();
1227	reinit_timer();
1228
1229	if (err == APM_NO_ERROR)
1230		err = APM_SUCCESS;
1231	if (err != APM_SUCCESS)
1232		apm_error("suspend", err);
1233	err = (err == APM_SUCCESS) ? 0 : -EIO;
1234
1235	syscore_resume();
1236	local_irq_enable();
1237
1238	dpm_resume_start(PMSG_RESUME);
1239	dpm_resume_end(PMSG_RESUME);
1240
1241	queue_event(APM_NORMAL_RESUME, NULL);
1242	spin_lock(&user_list_lock);
1243	for (as = user_list; as != NULL; as = as->next) {
1244		as->suspend_wait = 0;
1245		as->suspend_result = err;
1246	}
1247	spin_unlock(&user_list_lock);
1248	wake_up_interruptible(&apm_suspend_waitqueue);
1249	return err;
1250}
1251
1252static void standby(void)
1253{
1254	int err;
1255
1256	dpm_suspend_end(PMSG_SUSPEND);
1257
1258	local_irq_disable();
1259	syscore_suspend();
1260	local_irq_enable();
1261
1262	err = set_system_power_state(APM_STATE_STANDBY);
1263	if ((err != APM_SUCCESS) && (err != APM_NO_ERROR))
1264		apm_error("standby", err);
1265
1266	local_irq_disable();
1267	syscore_resume();
1268	local_irq_enable();
1269
1270	dpm_resume_start(PMSG_RESUME);
1271}
1272
1273static apm_event_t get_event(void)
1274{
1275	int error;
1276	apm_event_t event = APM_NO_EVENTS; /* silence gcc */
1277	apm_eventinfo_t	info;
1278
1279	static int notified;
1280
1281	/* we don't use the eventinfo */
1282	error = apm_get_event(&event, &info);
1283	if (error == APM_SUCCESS)
1284		return event;
1285
1286	if ((error != APM_NO_EVENTS) && (notified++ == 0))
1287		apm_error("get_event", error);
1288
1289	return 0;
1290}
1291
1292static void check_events(void)
1293{
1294	apm_event_t event;
1295	static unsigned long last_resume;
1296	static int ignore_bounce;
1297
1298	while ((event = get_event()) != 0) {
1299		if (debug) {
1300			if (event <= NR_APM_EVENT_NAME)
1301				printk(KERN_DEBUG "apm: received %s notify\n",
1302				       apm_event_name[event - 1]);
1303			else
1304				printk(KERN_DEBUG "apm: received unknown "
1305				       "event 0x%02x\n", event);
1306		}
1307		if (ignore_bounce
1308		    && (time_after(jiffies, last_resume + bounce_interval)))
1309			ignore_bounce = 0;
1310
1311		switch (event) {
1312		case APM_SYS_STANDBY:
1313		case APM_USER_STANDBY:
1314			queue_event(event, NULL);
1315			if (standbys_pending <= 0)
1316				standby();
1317			break;
1318
1319		case APM_USER_SUSPEND:
1320#ifdef CONFIG_APM_IGNORE_USER_SUSPEND
1321			if (apm_info.connection_version > 0x100)
1322				set_system_power_state(APM_STATE_REJECT);
1323			break;
1324#endif
1325		case APM_SYS_SUSPEND:
1326			if (ignore_bounce) {
1327				if (apm_info.connection_version > 0x100)
1328					set_system_power_state(APM_STATE_REJECT);
1329				break;
1330			}
1331			/*
1332			 * If we are already processing a SUSPEND,
1333			 * then further SUSPEND events from the BIOS
1334			 * will be ignored.  We also return here to
1335			 * cope with the fact that the Thinkpads keep
1336			 * sending a SUSPEND event until something else
1337			 * happens!
1338			 */
1339			if (ignore_sys_suspend)
1340				return;
1341			ignore_sys_suspend = 1;
1342			queue_event(event, NULL);
1343			if (suspends_pending <= 0)
1344				(void) suspend(1);
1345			break;
1346
1347		case APM_NORMAL_RESUME:
1348		case APM_CRITICAL_RESUME:
1349		case APM_STANDBY_RESUME:
1350			ignore_sys_suspend = 0;
1351			last_resume = jiffies;
1352			ignore_bounce = 1;
1353			if ((event != APM_NORMAL_RESUME)
1354			    || (ignore_normal_resume == 0)) {
1355				dpm_resume_end(PMSG_RESUME);
1356				queue_event(event, NULL);
1357			}
1358			ignore_normal_resume = 0;
1359			break;
1360
1361		case APM_CAPABILITY_CHANGE:
1362		case APM_LOW_BATTERY:
1363		case APM_POWER_STATUS_CHANGE:
1364			queue_event(event, NULL);
1365			/* If needed, notify drivers here */
1366			break;
1367
1368		case APM_UPDATE_TIME:
1369			break;
1370
1371		case APM_CRITICAL_SUSPEND:
1372			/*
1373			 * We are not allowed to reject a critical suspend.
1374			 */
1375			(void)suspend(0);
1376			break;
1377		}
1378	}
1379}
1380
1381static void apm_event_handler(void)
1382{
1383	static int pending_count = 4;
1384	int err;
1385
1386	if ((standbys_pending > 0) || (suspends_pending > 0)) {
1387		if ((apm_info.connection_version > 0x100) &&
1388		    (pending_count-- <= 0)) {
1389			pending_count = 4;
1390			if (debug)
1391				printk(KERN_DEBUG "apm: setting state busy\n");
1392			err = set_system_power_state(APM_STATE_BUSY);
1393			if (err)
1394				apm_error("busy", err);
1395		}
1396	} else
1397		pending_count = 4;
1398	check_events();
1399}
1400
1401/*
1402 * This is the APM thread main loop.
1403 */
1404
1405static void apm_mainloop(void)
1406{
1407	DECLARE_WAITQUEUE(wait, current);
1408
1409	add_wait_queue(&apm_waitqueue, &wait);
1410	set_current_state(TASK_INTERRUPTIBLE);
1411	for (;;) {
1412		schedule_timeout(APM_CHECK_TIMEOUT);
1413		if (kthread_should_stop())
1414			break;
1415		/*
1416		 * Ok, check all events, check for idle (and mark us sleeping
1417		 * so as not to count towards the load average)..
1418		 */
1419		set_current_state(TASK_INTERRUPTIBLE);
1420		apm_event_handler();
1421	}
1422	remove_wait_queue(&apm_waitqueue, &wait);
1423}
1424
1425static int check_apm_user(struct apm_user *as, const char *func)
1426{
1427	if (as == NULL || as->magic != APM_BIOS_MAGIC) {
1428		pr_err("%s passed bad filp\n", func);
1429		return 1;
1430	}
1431	return 0;
1432}
1433
1434static ssize_t do_read(struct file *fp, char __user *buf, size_t count, loff_t *ppos)
1435{
1436	struct apm_user *as;
1437	int i;
1438	apm_event_t event;
1439
1440	as = fp->private_data;
1441	if (check_apm_user(as, "read"))
1442		return -EIO;
1443	if ((int)count < sizeof(apm_event_t))
1444		return -EINVAL;
1445	if ((queue_empty(as)) && (fp->f_flags & O_NONBLOCK))
1446		return -EAGAIN;
1447	wait_event_interruptible(apm_waitqueue, !queue_empty(as));
1448	i = count;
1449	while ((i >= sizeof(event)) && !queue_empty(as)) {
1450		event = get_queued_event(as);
1451		if (copy_to_user(buf, &event, sizeof(event))) {
1452			if (i < count)
1453				break;
1454			return -EFAULT;
1455		}
1456		switch (event) {
1457		case APM_SYS_SUSPEND:
1458		case APM_USER_SUSPEND:
1459			as->suspends_read++;
1460			break;
1461
1462		case APM_SYS_STANDBY:
1463		case APM_USER_STANDBY:
1464			as->standbys_read++;
1465			break;
1466		}
1467		buf += sizeof(event);
1468		i -= sizeof(event);
1469	}
1470	if (i < count)
1471		return count - i;
1472	if (signal_pending(current))
1473		return -ERESTARTSYS;
1474	return 0;
1475}
1476
1477static __poll_t do_poll(struct file *fp, poll_table *wait)
1478{
1479	struct apm_user *as;
1480
1481	as = fp->private_data;
1482	if (check_apm_user(as, "poll"))
1483		return 0;
1484	poll_wait(fp, &apm_waitqueue, wait);
1485	if (!queue_empty(as))
1486		return EPOLLIN | EPOLLRDNORM;
1487	return 0;
1488}
1489
1490static long do_ioctl(struct file *filp, u_int cmd, u_long arg)
1491{
1492	struct apm_user *as;
1493	int ret;
1494
1495	as = filp->private_data;
1496	if (check_apm_user(as, "ioctl"))
1497		return -EIO;
1498	if (!as->suser || !as->writer)
1499		return -EPERM;
1500	switch (cmd) {
1501	case APM_IOC_STANDBY:
1502		mutex_lock(&apm_mutex);
1503		if (as->standbys_read > 0) {
1504			as->standbys_read--;
1505			as->standbys_pending--;
1506			standbys_pending--;
1507		} else
1508			queue_event(APM_USER_STANDBY, as);
1509		if (standbys_pending <= 0)
1510			standby();
1511		mutex_unlock(&apm_mutex);
1512		break;
1513	case APM_IOC_SUSPEND:
1514		mutex_lock(&apm_mutex);
1515		if (as->suspends_read > 0) {
1516			as->suspends_read--;
1517			as->suspends_pending--;
1518			suspends_pending--;
1519		} else
1520			queue_event(APM_USER_SUSPEND, as);
1521		if (suspends_pending <= 0) {
1522			ret = suspend(1);
1523			mutex_unlock(&apm_mutex);
1524		} else {
1525			as->suspend_wait = 1;
1526			mutex_unlock(&apm_mutex);
1527			wait_event_interruptible(apm_suspend_waitqueue,
1528					as->suspend_wait == 0);
1529			ret = as->suspend_result;
1530		}
1531		return ret;
1532	default:
1533		return -ENOTTY;
1534	}
1535	return 0;
1536}
1537
1538static int do_release(struct inode *inode, struct file *filp)
1539{
1540	struct apm_user *as;
1541
1542	as = filp->private_data;
1543	if (check_apm_user(as, "release"))
1544		return 0;
1545	filp->private_data = NULL;
1546	if (as->standbys_pending > 0) {
1547		standbys_pending -= as->standbys_pending;
1548		if (standbys_pending <= 0)
1549			standby();
1550	}
1551	if (as->suspends_pending > 0) {
1552		suspends_pending -= as->suspends_pending;
1553		if (suspends_pending <= 0)
1554			(void) suspend(1);
1555	}
1556	spin_lock(&user_list_lock);
1557	if (user_list == as)
1558		user_list = as->next;
1559	else {
1560		struct apm_user *as1;
1561
1562		for (as1 = user_list;
1563		     (as1 != NULL) && (as1->next != as);
1564		     as1 = as1->next)
1565			;
1566		if (as1 == NULL)
1567			pr_err("filp not in user list\n");
1568		else
1569			as1->next = as->next;
1570	}
1571	spin_unlock(&user_list_lock);
1572	kfree(as);
1573	return 0;
1574}
1575
1576static int do_open(struct inode *inode, struct file *filp)
1577{
1578	struct apm_user *as;
1579
1580	as = kmalloc(sizeof(*as), GFP_KERNEL);
1581	if (as == NULL)
1582		return -ENOMEM;
1583
1584	as->magic = APM_BIOS_MAGIC;
1585	as->event_tail = as->event_head = 0;
1586	as->suspends_pending = as->standbys_pending = 0;
1587	as->suspends_read = as->standbys_read = 0;
1588	/*
1589	 * XXX - this is a tiny bit broken, when we consider BSD
1590	 * process accounting. If the device is opened by root, we
1591	 * instantly flag that we used superuser privs. Who knows,
1592	 * we might close the device immediately without doing a
1593	 * privileged operation -- cevans
1594	 */
1595	as->suser = capable(CAP_SYS_ADMIN);
1596	as->writer = (filp->f_mode & FMODE_WRITE) == FMODE_WRITE;
1597	as->reader = (filp->f_mode & FMODE_READ) == FMODE_READ;
1598	spin_lock(&user_list_lock);
1599	as->next = user_list;
1600	user_list = as;
1601	spin_unlock(&user_list_lock);
1602	filp->private_data = as;
1603	return 0;
1604}
1605
1606#ifdef CONFIG_PROC_FS
1607static int proc_apm_show(struct seq_file *m, void *v)
1608{
1609	unsigned short	bx;
1610	unsigned short	cx;
1611	unsigned short	dx;
1612	int		error;
1613	unsigned short  ac_line_status = 0xff;
1614	unsigned short  battery_status = 0xff;
1615	unsigned short  battery_flag   = 0xff;
1616	int		percentage     = -1;
1617	int             time_units     = -1;
1618	char            *units         = "?";
1619
1620	if ((num_online_cpus() == 1) &&
1621	    !(error = apm_get_power_status(&bx, &cx, &dx))) {
1622		ac_line_status = (bx >> 8) & 0xff;
1623		battery_status = bx & 0xff;
1624		if ((cx & 0xff) != 0xff)
1625			percentage = cx & 0xff;
1626
1627		if (apm_info.connection_version > 0x100) {
1628			battery_flag = (cx >> 8) & 0xff;
1629			if (dx != 0xffff) {
1630				units = (dx & 0x8000) ? "min" : "sec";
1631				time_units = dx & 0x7fff;
1632			}
1633		}
1634	}
1635	/* Arguments, with symbols from linux/apm_bios.h.  Information is
1636	   from the Get Power Status (0x0a) call unless otherwise noted.
1637
1638	   0) Linux driver version (this will change if format changes)
1639	   1) APM BIOS Version.  Usually 1.0, 1.1 or 1.2.
1640	   2) APM flags from APM Installation Check (0x00):
1641	      bit 0: APM_16_BIT_SUPPORT
1642	      bit 1: APM_32_BIT_SUPPORT
1643	      bit 2: APM_IDLE_SLOWS_CLOCK
1644	      bit 3: APM_BIOS_DISABLED
1645	      bit 4: APM_BIOS_DISENGAGED
1646	   3) AC line status
1647	      0x00: Off-line
1648	      0x01: On-line
1649	      0x02: On backup power (BIOS >= 1.1 only)
1650	      0xff: Unknown
1651	   4) Battery status
1652	      0x00: High
1653	      0x01: Low
1654	      0x02: Critical
1655	      0x03: Charging
1656	      0x04: Selected battery not present (BIOS >= 1.2 only)
1657	      0xff: Unknown
1658	   5) Battery flag
1659	      bit 0: High
1660	      bit 1: Low
1661	      bit 2: Critical
1662	      bit 3: Charging
1663	      bit 7: No system battery
1664	      0xff: Unknown
1665	   6) Remaining battery life (percentage of charge):
1666	      0-100: valid
1667	      -1: Unknown
1668	   7) Remaining battery life (time units):
1669	      Number of remaining minutes or seconds
1670	      -1: Unknown
1671	   8) min = minutes; sec = seconds */
1672
1673	seq_printf(m, "%s %d.%d 0x%02x 0x%02x 0x%02x 0x%02x %d%% %d %s\n",
1674		   driver_version,
1675		   (apm_info.bios.version >> 8) & 0xff,
1676		   apm_info.bios.version & 0xff,
1677		   apm_info.bios.flags,
1678		   ac_line_status,
1679		   battery_status,
1680		   battery_flag,
1681		   percentage,
1682		   time_units,
1683		   units);
1684	return 0;
1685}
1686#endif
 
 
 
 
 
 
 
 
 
 
 
 
1687
1688static int apm(void *unused)
1689{
1690	unsigned short	bx;
1691	unsigned short	cx;
1692	unsigned short	dx;
1693	int		error;
1694	char 		*power_stat;
1695	char 		*bat_stat;
1696
1697	/* 2002/08/01 - WT
1698	 * This is to avoid random crashes at boot time during initialization
1699	 * on SMP systems in case of "apm=power-off" mode. Seen on ASUS A7M266D.
1700	 * Some bioses don't like being called from CPU != 0.
1701	 * Method suggested by Ingo Molnar.
1702	 */
1703	set_cpus_allowed_ptr(current, cpumask_of(0));
1704	BUG_ON(smp_processor_id() != 0);
1705
1706	if (apm_info.connection_version == 0) {
1707		apm_info.connection_version = apm_info.bios.version;
1708		if (apm_info.connection_version > 0x100) {
1709			/*
1710			 * We only support BIOSs up to version 1.2
1711			 */
1712			if (apm_info.connection_version > 0x0102)
1713				apm_info.connection_version = 0x0102;
1714			error = apm_driver_version(&apm_info.connection_version);
1715			if (error != APM_SUCCESS) {
1716				apm_error("driver version", error);
1717				/* Fall back to an APM 1.0 connection. */
1718				apm_info.connection_version = 0x100;
1719			}
1720		}
1721	}
1722
1723	if (debug)
1724		printk(KERN_INFO "apm: Connection version %d.%d\n",
1725			(apm_info.connection_version >> 8) & 0xff,
1726			apm_info.connection_version & 0xff);
1727
1728#ifdef CONFIG_APM_DO_ENABLE
1729	if (apm_info.bios.flags & APM_BIOS_DISABLED) {
1730		/*
1731		 * This call causes my NEC UltraLite Versa 33/C to hang if it
1732		 * is booted with PM disabled but not in the docking station.
1733		 * Unfortunate ...
1734		 */
1735		error = apm_enable_power_management(1);
1736		if (error) {
1737			apm_error("enable power management", error);
1738			return -1;
1739		}
1740	}
1741#endif
1742
1743	if ((apm_info.bios.flags & APM_BIOS_DISENGAGED)
1744	    && (apm_info.connection_version > 0x0100)) {
1745		error = apm_engage_power_management(APM_DEVICE_ALL, 1);
1746		if (error) {
1747			apm_error("engage power management", error);
1748			return -1;
1749		}
1750	}
1751
1752	if (debug && (num_online_cpus() == 1 || smp)) {
1753		error = apm_get_power_status(&bx, &cx, &dx);
1754		if (error)
1755			printk(KERN_INFO "apm: power status not available\n");
1756		else {
1757			switch ((bx >> 8) & 0xff) {
1758			case 0:
1759				power_stat = "off line";
1760				break;
1761			case 1:
1762				power_stat = "on line";
1763				break;
1764			case 2:
1765				power_stat = "on backup power";
1766				break;
1767			default:
1768				power_stat = "unknown";
1769				break;
1770			}
1771			switch (bx & 0xff) {
1772			case 0:
1773				bat_stat = "high";
1774				break;
1775			case 1:
1776				bat_stat = "low";
1777				break;
1778			case 2:
1779				bat_stat = "critical";
1780				break;
1781			case 3:
1782				bat_stat = "charging";
1783				break;
1784			default:
1785				bat_stat = "unknown";
1786				break;
1787			}
1788			printk(KERN_INFO
1789			       "apm: AC %s, battery status %s, battery life ",
1790			       power_stat, bat_stat);
1791			if ((cx & 0xff) == 0xff)
1792				printk("unknown\n");
1793			else
1794				printk("%d%%\n", cx & 0xff);
1795			if (apm_info.connection_version > 0x100) {
1796				printk(KERN_INFO
1797				       "apm: battery flag 0x%02x, battery life ",
1798				       (cx >> 8) & 0xff);
1799				if (dx == 0xffff)
1800					printk("unknown\n");
1801				else
1802					printk("%d %s\n", dx & 0x7fff,
1803					       (dx & 0x8000) ?
1804					       "minutes" : "seconds");
1805			}
1806		}
1807	}
1808
1809	/* Install our power off handler.. */
1810	if (power_off)
1811		pm_power_off = apm_power_off;
1812
1813	if (num_online_cpus() == 1 || smp) {
1814#if defined(CONFIG_APM_DISPLAY_BLANK) && defined(CONFIG_VT)
1815		console_blank_hook = apm_console_blank;
1816#endif
1817		apm_mainloop();
1818#if defined(CONFIG_APM_DISPLAY_BLANK) && defined(CONFIG_VT)
1819		console_blank_hook = NULL;
1820#endif
1821	}
1822
1823	return 0;
1824}
1825
1826#ifndef MODULE
1827static int __init apm_setup(char *str)
1828{
1829	int invert;
1830
1831	while ((str != NULL) && (*str != '\0')) {
1832		if (strncmp(str, "off", 3) == 0)
1833			apm_disabled = 1;
1834		if (strncmp(str, "on", 2) == 0)
1835			apm_disabled = 0;
1836		if ((strncmp(str, "bounce-interval=", 16) == 0) ||
1837		    (strncmp(str, "bounce_interval=", 16) == 0))
1838			bounce_interval = simple_strtol(str + 16, NULL, 0);
1839		if ((strncmp(str, "idle-threshold=", 15) == 0) ||
1840		    (strncmp(str, "idle_threshold=", 15) == 0))
1841			idle_threshold = simple_strtol(str + 15, NULL, 0);
1842		if ((strncmp(str, "idle-period=", 12) == 0) ||
1843		    (strncmp(str, "idle_period=", 12) == 0))
1844			idle_period = simple_strtol(str + 12, NULL, 0);
1845		invert = (strncmp(str, "no-", 3) == 0) ||
1846			(strncmp(str, "no_", 3) == 0);
1847		if (invert)
1848			str += 3;
1849		if (strncmp(str, "debug", 5) == 0)
1850			debug = !invert;
1851		if ((strncmp(str, "power-off", 9) == 0) ||
1852		    (strncmp(str, "power_off", 9) == 0))
1853			power_off = !invert;
1854		if (strncmp(str, "smp", 3) == 0) {
1855			smp = !invert;
1856			idle_threshold = 100;
1857		}
1858		if ((strncmp(str, "allow-ints", 10) == 0) ||
1859		    (strncmp(str, "allow_ints", 10) == 0))
1860			apm_info.allow_ints = !invert;
1861		if ((strncmp(str, "broken-psr", 10) == 0) ||
1862		    (strncmp(str, "broken_psr", 10) == 0))
1863			apm_info.get_power_status_broken = !invert;
1864		if ((strncmp(str, "realmode-power-off", 18) == 0) ||
1865		    (strncmp(str, "realmode_power_off", 18) == 0))
1866			apm_info.realmode_power_off = !invert;
1867		str = strchr(str, ',');
1868		if (str != NULL)
1869			str += strspn(str, ", \t");
1870	}
1871	return 1;
1872}
1873
1874__setup("apm=", apm_setup);
1875#endif
1876
1877static const struct file_operations apm_bios_fops = {
1878	.owner		= THIS_MODULE,
1879	.read		= do_read,
1880	.poll		= do_poll,
1881	.unlocked_ioctl	= do_ioctl,
1882	.open		= do_open,
1883	.release	= do_release,
1884	.llseek		= noop_llseek,
1885};
1886
1887static struct miscdevice apm_device = {
1888	APM_MINOR_DEV,
1889	"apm_bios",
1890	&apm_bios_fops
1891};
1892
1893
1894/* Simple "print if true" callback */
1895static int __init print_if_true(const struct dmi_system_id *d)
1896{
1897	printk("%s\n", d->ident);
1898	return 0;
1899}
1900
1901/*
1902 * Some Bioses enable the PS/2 mouse (touchpad) at resume, even if it was
1903 * disabled before the suspend. Linux used to get terribly confused by that.
1904 */
1905static int __init broken_ps2_resume(const struct dmi_system_id *d)
1906{
1907	printk(KERN_INFO "%s machine detected. Mousepad Resume Bug "
1908	       "workaround hopefully not needed.\n", d->ident);
1909	return 0;
1910}
1911
1912/* Some bioses have a broken protected mode poweroff and need to use realmode */
1913static int __init set_realmode_power_off(const struct dmi_system_id *d)
1914{
1915	if (apm_info.realmode_power_off == 0) {
1916		apm_info.realmode_power_off = 1;
1917		printk(KERN_INFO "%s bios detected. "
1918		       "Using realmode poweroff only.\n", d->ident);
1919	}
1920	return 0;
1921}
1922
1923/* Some laptops require interrupts to be enabled during APM calls */
1924static int __init set_apm_ints(const struct dmi_system_id *d)
1925{
1926	if (apm_info.allow_ints == 0) {
1927		apm_info.allow_ints = 1;
1928		printk(KERN_INFO "%s machine detected. "
1929		       "Enabling interrupts during APM calls.\n", d->ident);
1930	}
1931	return 0;
1932}
1933
1934/* Some APM bioses corrupt memory or just plain do not work */
1935static int __init apm_is_horked(const struct dmi_system_id *d)
1936{
1937	if (apm_info.disabled == 0) {
1938		apm_info.disabled = 1;
1939		printk(KERN_INFO "%s machine detected. "
1940		       "Disabling APM.\n", d->ident);
1941	}
1942	return 0;
1943}
1944
1945static int __init apm_is_horked_d850md(const struct dmi_system_id *d)
1946{
1947	if (apm_info.disabled == 0) {
1948		apm_info.disabled = 1;
1949		printk(KERN_INFO "%s machine detected. "
1950		       "Disabling APM.\n", d->ident);
1951		printk(KERN_INFO "This bug is fixed in bios P15 which is available for\n");
1952		printk(KERN_INFO "download from support.intel.com\n");
1953	}
1954	return 0;
1955}
1956
1957/* Some APM bioses hang on APM idle calls */
1958static int __init apm_likes_to_melt(const struct dmi_system_id *d)
1959{
1960	if (apm_info.forbid_idle == 0) {
1961		apm_info.forbid_idle = 1;
1962		printk(KERN_INFO "%s machine detected. "
1963		       "Disabling APM idle calls.\n", d->ident);
1964	}
1965	return 0;
1966}
1967
1968/*
1969 *  Check for clue free BIOS implementations who use
1970 *  the following QA technique
1971 *
1972 *      [ Write BIOS Code ]<------
1973 *               |                ^
1974 *      < Does it Compile >----N--
1975 *               |Y               ^
1976 *	< Does it Boot Win98 >-N--
1977 *               |Y
1978 *           [Ship It]
1979 *
1980 *	Phoenix A04  08/24/2000 is known bad (Dell Inspiron 5000e)
1981 *	Phoenix A07  09/29/2000 is known good (Dell Inspiron 5000)
1982 */
1983static int __init broken_apm_power(const struct dmi_system_id *d)
1984{
1985	apm_info.get_power_status_broken = 1;
1986	printk(KERN_WARNING "BIOS strings suggest APM bugs, "
1987	       "disabling power status reporting.\n");
1988	return 0;
1989}
1990
1991/*
1992 * This bios swaps the APM minute reporting bytes over (Many sony laptops
1993 * have this problem).
1994 */
1995static int __init swab_apm_power_in_minutes(const struct dmi_system_id *d)
1996{
1997	apm_info.get_power_status_swabinminutes = 1;
1998	printk(KERN_WARNING "BIOS strings suggest APM reports battery life "
1999	       "in minutes and wrong byte order.\n");
2000	return 0;
2001}
2002
2003static const struct dmi_system_id apm_dmi_table[] __initconst = {
2004	{
2005		print_if_true,
2006		KERN_WARNING "IBM T23 - BIOS 1.03b+ and controller firmware 1.02+ may be needed for Linux APM.",
2007		{	DMI_MATCH(DMI_SYS_VENDOR, "IBM"),
2008			DMI_MATCH(DMI_BIOS_VERSION, "1AET38WW (1.01b)"), },
2009	},
2010	{	/* Handle problems with APM on the C600 */
2011		broken_ps2_resume, "Dell Latitude C600",
2012		{	DMI_MATCH(DMI_SYS_VENDOR, "Dell"),
2013			DMI_MATCH(DMI_PRODUCT_NAME, "Latitude C600"), },
2014	},
2015	{	/* Allow interrupts during suspend on Dell Latitude laptops*/
2016		set_apm_ints, "Dell Latitude",
2017		{	DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
2018			DMI_MATCH(DMI_PRODUCT_NAME, "Latitude C510"), }
2019	},
2020	{	/* APM crashes */
2021		apm_is_horked, "Dell Inspiron 2500",
2022		{	DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
2023			DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 2500"),
2024			DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2025			DMI_MATCH(DMI_BIOS_VERSION, "A11"), },
2026	},
2027	{	/* Allow interrupts during suspend on Dell Inspiron laptops*/
2028		set_apm_ints, "Dell Inspiron", {
2029			DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
2030			DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 4000"), },
2031	},
2032	{	/* Handle problems with APM on Inspiron 5000e */
2033		broken_apm_power, "Dell Inspiron 5000e",
2034		{	DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2035			DMI_MATCH(DMI_BIOS_VERSION, "A04"),
2036			DMI_MATCH(DMI_BIOS_DATE, "08/24/2000"), },
2037	},
2038	{	/* Handle problems with APM on Inspiron 2500 */
2039		broken_apm_power, "Dell Inspiron 2500",
2040		{	DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2041			DMI_MATCH(DMI_BIOS_VERSION, "A12"),
2042			DMI_MATCH(DMI_BIOS_DATE, "02/04/2002"), },
2043	},
2044	{	/* APM crashes */
2045		apm_is_horked, "Dell Dimension 4100",
2046		{	DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
2047			DMI_MATCH(DMI_PRODUCT_NAME, "XPS-Z"),
2048			DMI_MATCH(DMI_BIOS_VENDOR, "Intel Corp."),
2049			DMI_MATCH(DMI_BIOS_VERSION, "A11"), },
2050	},
2051	{	/* Allow interrupts during suspend on Compaq Laptops*/
2052		set_apm_ints, "Compaq 12XL125",
2053		{	DMI_MATCH(DMI_SYS_VENDOR, "Compaq"),
2054			DMI_MATCH(DMI_PRODUCT_NAME, "Compaq PC"),
2055			DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2056			DMI_MATCH(DMI_BIOS_VERSION, "4.06"), },
2057	},
2058	{	/* Allow interrupts during APM or the clock goes slow */
2059		set_apm_ints, "ASUSTeK",
2060		{	DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK Computer Inc."),
2061			DMI_MATCH(DMI_PRODUCT_NAME, "L8400K series Notebook PC"), },
2062	},
2063	{	/* APM blows on shutdown */
2064		apm_is_horked, "ABIT KX7-333[R]",
2065		{	DMI_MATCH(DMI_BOARD_VENDOR, "ABIT"),
2066			DMI_MATCH(DMI_BOARD_NAME, "VT8367-8233A (KX7-333[R])"), },
2067	},
2068	{	/* APM crashes */
2069		apm_is_horked, "Trigem Delhi3",
2070		{	DMI_MATCH(DMI_SYS_VENDOR, "TriGem Computer, Inc"),
2071			DMI_MATCH(DMI_PRODUCT_NAME, "Delhi3"), },
2072	},
2073	{	/* APM crashes */
2074		apm_is_horked, "Fujitsu-Siemens",
2075		{	DMI_MATCH(DMI_BIOS_VENDOR, "hoenix/FUJITSU SIEMENS"),
2076			DMI_MATCH(DMI_BIOS_VERSION, "Version1.01"), },
2077	},
2078	{	/* APM crashes */
2079		apm_is_horked_d850md, "Intel D850MD",
2080		{	DMI_MATCH(DMI_BIOS_VENDOR, "Intel Corp."),
2081			DMI_MATCH(DMI_BIOS_VERSION, "MV85010A.86A.0016.P07.0201251536"), },
2082	},
2083	{	/* APM crashes */
2084		apm_is_horked, "Intel D810EMO",
2085		{	DMI_MATCH(DMI_BIOS_VENDOR, "Intel Corp."),
2086			DMI_MATCH(DMI_BIOS_VERSION, "MO81010A.86A.0008.P04.0004170800"), },
2087	},
2088	{	/* APM crashes */
2089		apm_is_horked, "Dell XPS-Z",
2090		{	DMI_MATCH(DMI_BIOS_VENDOR, "Intel Corp."),
2091			DMI_MATCH(DMI_BIOS_VERSION, "A11"),
2092			DMI_MATCH(DMI_PRODUCT_NAME, "XPS-Z"), },
2093	},
2094	{	/* APM crashes */
2095		apm_is_horked, "Sharp PC-PJ/AX",
2096		{	DMI_MATCH(DMI_SYS_VENDOR, "SHARP"),
2097			DMI_MATCH(DMI_PRODUCT_NAME, "PC-PJ/AX"),
2098			DMI_MATCH(DMI_BIOS_VENDOR, "SystemSoft"),
2099			DMI_MATCH(DMI_BIOS_VERSION, "Version R2.08"), },
2100	},
2101	{	/* APM crashes */
2102		apm_is_horked, "Dell Inspiron 2500",
2103		{	DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
2104			DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 2500"),
2105			DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2106			DMI_MATCH(DMI_BIOS_VERSION, "A11"), },
2107	},
2108	{	/* APM idle hangs */
2109		apm_likes_to_melt, "Jabil AMD",
2110		{	DMI_MATCH(DMI_BIOS_VENDOR, "American Megatrends Inc."),
2111			DMI_MATCH(DMI_BIOS_VERSION, "0AASNP06"), },
2112	},
2113	{	/* APM idle hangs */
2114		apm_likes_to_melt, "AMI Bios",
2115		{	DMI_MATCH(DMI_BIOS_VENDOR, "American Megatrends Inc."),
2116			DMI_MATCH(DMI_BIOS_VERSION, "0AASNP05"), },
2117	},
2118	{	/* Handle problems with APM on Sony Vaio PCG-N505X(DE) */
2119		swab_apm_power_in_minutes, "Sony VAIO",
2120		{	DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2121			DMI_MATCH(DMI_BIOS_VERSION, "R0206H"),
2122			DMI_MATCH(DMI_BIOS_DATE, "08/23/99"), },
2123	},
2124	{	/* Handle problems with APM on Sony Vaio PCG-N505VX */
2125		swab_apm_power_in_minutes, "Sony VAIO",
2126		{	DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2127			DMI_MATCH(DMI_BIOS_VERSION, "W2K06H0"),
2128			DMI_MATCH(DMI_BIOS_DATE, "02/03/00"), },
2129	},
2130	{	/* Handle problems with APM on Sony Vaio PCG-XG29 */
2131		swab_apm_power_in_minutes, "Sony VAIO",
2132		{	DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2133			DMI_MATCH(DMI_BIOS_VERSION, "R0117A0"),
2134			DMI_MATCH(DMI_BIOS_DATE, "04/25/00"), },
2135	},
2136	{	/* Handle problems with APM on Sony Vaio PCG-Z600NE */
2137		swab_apm_power_in_minutes, "Sony VAIO",
2138		{	DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2139			DMI_MATCH(DMI_BIOS_VERSION, "R0121Z1"),
2140			DMI_MATCH(DMI_BIOS_DATE, "05/11/00"), },
2141	},
2142	{	/* Handle problems with APM on Sony Vaio PCG-Z600NE */
2143		swab_apm_power_in_minutes, "Sony VAIO",
2144		{	DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2145			DMI_MATCH(DMI_BIOS_VERSION, "WME01Z1"),
2146			DMI_MATCH(DMI_BIOS_DATE, "08/11/00"), },
2147	},
2148	{	/* Handle problems with APM on Sony Vaio PCG-Z600LEK(DE) */
2149		swab_apm_power_in_minutes, "Sony VAIO",
2150		{	DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2151			DMI_MATCH(DMI_BIOS_VERSION, "R0206Z3"),
2152			DMI_MATCH(DMI_BIOS_DATE, "12/25/00"), },
2153	},
2154	{	/* Handle problems with APM on Sony Vaio PCG-Z505LS */
2155		swab_apm_power_in_minutes, "Sony VAIO",
2156		{	DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2157			DMI_MATCH(DMI_BIOS_VERSION, "R0203D0"),
2158			DMI_MATCH(DMI_BIOS_DATE, "05/12/00"), },
2159	},
2160	{	/* Handle problems with APM on Sony Vaio PCG-Z505LS */
2161		swab_apm_power_in_minutes, "Sony VAIO",
2162		{	DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2163			DMI_MATCH(DMI_BIOS_VERSION, "R0203Z3"),
2164			DMI_MATCH(DMI_BIOS_DATE, "08/25/00"), },
2165	},
2166	{	/* Handle problems with APM on Sony Vaio PCG-Z505LS (with updated BIOS) */
2167		swab_apm_power_in_minutes, "Sony VAIO",
2168		{	DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2169			DMI_MATCH(DMI_BIOS_VERSION, "R0209Z3"),
2170			DMI_MATCH(DMI_BIOS_DATE, "05/12/01"), },
2171	},
2172	{	/* Handle problems with APM on Sony Vaio PCG-F104K */
2173		swab_apm_power_in_minutes, "Sony VAIO",
2174		{	DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2175			DMI_MATCH(DMI_BIOS_VERSION, "R0204K2"),
2176			DMI_MATCH(DMI_BIOS_DATE, "08/28/00"), },
2177	},
2178
2179	{	/* Handle problems with APM on Sony Vaio PCG-C1VN/C1VE */
2180		swab_apm_power_in_minutes, "Sony VAIO",
2181		{	DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2182			DMI_MATCH(DMI_BIOS_VERSION, "R0208P1"),
2183			DMI_MATCH(DMI_BIOS_DATE, "11/09/00"), },
2184	},
2185	{	/* Handle problems with APM on Sony Vaio PCG-C1VE */
2186		swab_apm_power_in_minutes, "Sony VAIO",
2187		{	DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2188			DMI_MATCH(DMI_BIOS_VERSION, "R0204P1"),
2189			DMI_MATCH(DMI_BIOS_DATE, "09/12/00"), },
2190	},
2191	{	/* Handle problems with APM on Sony Vaio PCG-C1VE */
2192		swab_apm_power_in_minutes, "Sony VAIO",
2193		{	DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2194			DMI_MATCH(DMI_BIOS_VERSION, "WXPO1Z3"),
2195			DMI_MATCH(DMI_BIOS_DATE, "10/26/01"), },
2196	},
2197	{	/* broken PM poweroff bios */
2198		set_realmode_power_off, "Award Software v4.60 PGMA",
2199		{	DMI_MATCH(DMI_BIOS_VENDOR, "Award Software International, Inc."),
2200			DMI_MATCH(DMI_BIOS_VERSION, "4.60 PGMA"),
2201			DMI_MATCH(DMI_BIOS_DATE, "134526184"), },
2202	},
2203
2204	/* Generic per vendor APM settings  */
2205
2206	{	/* Allow interrupts during suspend on IBM laptops */
2207		set_apm_ints, "IBM",
2208		{	DMI_MATCH(DMI_SYS_VENDOR, "IBM"), },
2209	},
2210
2211	{ }
2212};
2213
2214/*
2215 * Just start the APM thread. We do NOT want to do APM BIOS
2216 * calls from anything but the APM thread, if for no other reason
2217 * than the fact that we don't trust the APM BIOS. This way,
2218 * most common APM BIOS problems that lead to protection errors
2219 * etc will have at least some level of being contained...
2220 *
2221 * In short, if something bad happens, at least we have a choice
2222 * of just killing the apm thread..
2223 */
2224static int __init apm_init(void)
2225{
2226	struct desc_struct *gdt;
2227	int err;
2228
2229	dmi_check_system(apm_dmi_table);
2230
2231	if (apm_info.bios.version == 0 || machine_is_olpc()) {
2232		printk(KERN_INFO "apm: BIOS not found.\n");
2233		return -ENODEV;
2234	}
2235	printk(KERN_INFO
2236	       "apm: BIOS version %d.%d Flags 0x%02x (Driver version %s)\n",
2237	       ((apm_info.bios.version >> 8) & 0xff),
2238	       (apm_info.bios.version & 0xff),
2239	       apm_info.bios.flags,
2240	       driver_version);
2241	if ((apm_info.bios.flags & APM_32_BIT_SUPPORT) == 0) {
2242		printk(KERN_INFO "apm: no 32 bit BIOS support\n");
2243		return -ENODEV;
2244	}
2245
2246	if (allow_ints)
2247		apm_info.allow_ints = 1;
2248	if (broken_psr)
2249		apm_info.get_power_status_broken = 1;
2250	if (realmode_power_off)
2251		apm_info.realmode_power_off = 1;
2252	/* User can override, but default is to trust DMI */
2253	if (apm_disabled != -1)
2254		apm_info.disabled = apm_disabled;
2255
2256	/*
2257	 * Fix for the Compaq Contura 3/25c which reports BIOS version 0.1
2258	 * but is reportedly a 1.0 BIOS.
2259	 */
2260	if (apm_info.bios.version == 0x001)
2261		apm_info.bios.version = 0x100;
2262
2263	/* BIOS < 1.2 doesn't set cseg_16_len */
2264	if (apm_info.bios.version < 0x102)
2265		apm_info.bios.cseg_16_len = 0; /* 64k */
2266
2267	if (debug) {
2268		printk(KERN_INFO "apm: entry %x:%x cseg16 %x dseg %x",
2269			apm_info.bios.cseg, apm_info.bios.offset,
2270			apm_info.bios.cseg_16, apm_info.bios.dseg);
2271		if (apm_info.bios.version > 0x100)
2272			printk(" cseg len %x, dseg len %x",
2273				apm_info.bios.cseg_len,
2274				apm_info.bios.dseg_len);
2275		if (apm_info.bios.version > 0x101)
2276			printk(" cseg16 len %x", apm_info.bios.cseg_16_len);
2277		printk("\n");
2278	}
2279
2280	if (apm_info.disabled) {
2281		pr_notice("disabled on user request.\n");
2282		return -ENODEV;
2283	}
2284	if ((num_online_cpus() > 1) && !power_off && !smp) {
2285		pr_notice("disabled - APM is not SMP safe.\n");
2286		apm_info.disabled = 1;
2287		return -ENODEV;
2288	}
2289	if (!acpi_disabled) {
2290		pr_notice("overridden by ACPI.\n");
2291		apm_info.disabled = 1;
2292		return -ENODEV;
2293	}
2294
2295	/*
2296	 * Set up the long jump entry point to the APM BIOS, which is called
2297	 * from inline assembly.
2298	 */
2299	apm_bios_entry.offset = apm_info.bios.offset;
2300	apm_bios_entry.segment = APM_CS;
2301
2302	/*
2303	 * The APM 1.1 BIOS is supposed to provide limit information that it
2304	 * recognizes.  Many machines do this correctly, but many others do
2305	 * not restrict themselves to their claimed limit.  When this happens,
2306	 * they will cause a segmentation violation in the kernel at boot time.
2307	 * Most BIOS's, however, will respect a 64k limit, so we use that.
2308	 *
2309	 * Note we only set APM segments on CPU zero, since we pin the APM
2310	 * code to that CPU.
2311	 */
2312	gdt = get_cpu_gdt_rw(0);
2313	set_desc_base(&gdt[APM_CS >> 3],
2314		 (unsigned long)__va((unsigned long)apm_info.bios.cseg << 4));
2315	set_desc_base(&gdt[APM_CS_16 >> 3],
2316		 (unsigned long)__va((unsigned long)apm_info.bios.cseg_16 << 4));
2317	set_desc_base(&gdt[APM_DS >> 3],
2318		 (unsigned long)__va((unsigned long)apm_info.bios.dseg << 4));
2319
2320	proc_create_single("apm", 0, NULL, proc_apm_show);
2321
2322	kapmd_task = kthread_create(apm, NULL, "kapmd");
2323	if (IS_ERR(kapmd_task)) {
2324		pr_err("disabled - Unable to start kernel thread\n");
2325		err = PTR_ERR(kapmd_task);
2326		kapmd_task = NULL;
2327		remove_proc_entry("apm", NULL);
2328		return err;
2329	}
2330	wake_up_process(kapmd_task);
2331
2332	if (num_online_cpus() > 1 && !smp) {
2333		printk(KERN_NOTICE
2334		       "apm: disabled - APM is not SMP safe (power off active).\n");
2335		return 0;
2336	}
2337
2338	/*
2339	 * Note we don't actually care if the misc_device cannot be registered.
2340	 * this driver can do its job without it, even if userspace can't
2341	 * control it.  just log the error
2342	 */
2343	if (misc_register(&apm_device))
2344		printk(KERN_WARNING "apm: Could not register misc device.\n");
2345
2346	if (HZ != 100)
2347		idle_period = (idle_period * HZ) / 100;
2348	if (idle_threshold < 100) {
2349		cpuidle_poll_state_init(&apm_idle_driver);
2350		if (!cpuidle_register_driver(&apm_idle_driver))
2351			if (cpuidle_register_device(&apm_cpuidle_device))
2352				cpuidle_unregister_driver(&apm_idle_driver);
2353	}
2354
2355	return 0;
2356}
2357
2358static void __exit apm_exit(void)
2359{
2360	int error;
2361
2362	cpuidle_unregister_device(&apm_cpuidle_device);
2363	cpuidle_unregister_driver(&apm_idle_driver);
2364
2365	if (((apm_info.bios.flags & APM_BIOS_DISENGAGED) == 0)
2366	    && (apm_info.connection_version > 0x0100)) {
2367		error = apm_engage_power_management(APM_DEVICE_ALL, 0);
2368		if (error)
2369			apm_error("disengage power management", error);
2370	}
2371	misc_deregister(&apm_device);
2372	remove_proc_entry("apm", NULL);
2373	if (power_off)
2374		pm_power_off = NULL;
2375	if (kapmd_task) {
2376		kthread_stop(kapmd_task);
2377		kapmd_task = NULL;
2378	}
2379}
2380
2381module_init(apm_init);
2382module_exit(apm_exit);
2383
2384MODULE_AUTHOR("Stephen Rothwell");
2385MODULE_DESCRIPTION("Advanced Power Management");
2386MODULE_LICENSE("GPL");
2387module_param(debug, bool, 0644);
2388MODULE_PARM_DESC(debug, "Enable debug mode");
2389module_param(power_off, bool, 0444);
2390MODULE_PARM_DESC(power_off, "Enable power off");
2391module_param(bounce_interval, int, 0444);
2392MODULE_PARM_DESC(bounce_interval,
2393		"Set the number of ticks to ignore suspend bounces");
2394module_param(allow_ints, bool, 0444);
2395MODULE_PARM_DESC(allow_ints, "Allow interrupts during BIOS calls");
2396module_param(broken_psr, bool, 0444);
2397MODULE_PARM_DESC(broken_psr, "BIOS has a broken GetPowerStatus call");
2398module_param(realmode_power_off, bool, 0444);
2399MODULE_PARM_DESC(realmode_power_off,
2400		"Switch to real mode before powering off");
2401module_param(idle_threshold, int, 0444);
2402MODULE_PARM_DESC(idle_threshold,
2403	"System idle percentage above which to make APM BIOS idle calls");
2404module_param(idle_period, int, 0444);
2405MODULE_PARM_DESC(idle_period,
2406	"Period (in sec/100) over which to calculate the idle percentage");
2407module_param(smp, bool, 0444);
2408MODULE_PARM_DESC(smp,
2409	"Set this to enable APM use on an SMP platform. Use with caution on older systems");
2410MODULE_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);