Linux-2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

1 files changed, 2428 insertions, 0 deletions

diff --git a/arch/i386/kernel/apm.c b/arch/i386/kernel/apm.c
new file mode 100644
index 000000000000..45641a872550
--- /dev/null
+++ b/arch/i386/kernel/apm.c
@@ -0,0 +1,2428 @@
+/* -*- linux-c -*-
+ * APM BIOS driver for Linux
+ * Copyright 1994-2001 Stephen Rothwell (sfr@canb.auug.org.au)
+ *
+ * Initial development of this driver was funded by NEC Australia P/L
+ *	and NEC Corporation
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2, or (at your option) any
+ * later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * October 1995, Rik Faith (faith@cs.unc.edu):
+ *    Minor enhancements and updates (to the patch set) for 1.3.x
+ *    Documentation
+ * January 1996, Rik Faith (faith@cs.unc.edu):
+ *    Make /proc/apm easy to format (bump driver version)
+ * March 1996, Rik Faith (faith@cs.unc.edu):
+ *    Prohibit APM BIOS calls unless apm_enabled.
+ *    (Thanks to Ulrich Windl <Ulrich.Windl@rz.uni-regensburg.de>)
+ * April 1996, Stephen Rothwell (sfr@canb.auug.org.au)
+ *    Version 1.0 and 1.1
+ * May 1996, Version 1.2
+ * Feb 1998, Version 1.3
+ * Feb 1998, Version 1.4
+ * Aug 1998, Version 1.5
+ * Sep 1998, Version 1.6
+ * Nov 1998, Version 1.7
+ * Jan 1999, Version 1.8
+ * Jan 1999, Version 1.9
+ * Oct 1999, Version 1.10
+ * Nov 1999, Version 1.11
+ * Jan 2000, Version 1.12
+ * Feb 2000, Version 1.13
+ * Nov 2000, Version 1.14
+ * Oct 2001, Version 1.15
+ * Jan 2002, Version 1.16
+ * Oct 2002, Version 1.16ac
+ *
+ * History:
+ *    0.6b: first version in official kernel, Linux 1.3.46
+ *    0.7: changed /proc/apm format, Linux 1.3.58
+ *    0.8: fixed gcc 2.7.[12] compilation problems, Linux 1.3.59
+ *    0.9: only call bios if bios is present, Linux 1.3.72
+ *    1.0: use fixed device number, consolidate /proc/apm into this file,
+ *         Linux 1.3.85
+ *    1.1: support user-space standby and suspend, power off after system
+ *         halted, Linux 1.3.98
+ *    1.2: When resetting RTC after resume, take care so that the time
+ *         is only incorrect by 30-60mS (vs. 1S previously) (Gabor J. Toth
+ *         <jtoth@princeton.edu>); improve interaction between
+ *         screen-blanking and gpm (Stephen Rothwell); Linux 1.99.4
+ *    1.2a:Simple change to stop mysterious bug reports with SMP also added
+ *	   levels to the printk calls. APM is not defined for SMP machines.
+ *         The new replacment for it is, but Linux doesn't yet support this.
+ *         Alan Cox Linux 2.1.55
+ *    1.3: Set up a valid data descriptor 0x40 for buggy BIOS's
+ *    1.4: Upgraded to support APM 1.2. Integrated ThinkPad suspend patch by
+ *         Dean Gaudet <dgaudet@arctic.org>.
+ *         C. Scott Ananian <cananian@alumni.princeton.edu> Linux 2.1.87
+ *    1.5: Fix segment register reloading (in case of bad segments saved
+ *         across BIOS call).
+ *         Stephen Rothwell
+ *    1.6: Cope with complier/assembler differences.
+ *         Only try to turn off the first display device.
+ *         Fix OOPS at power off with no APM BIOS by Jan Echternach
+ *                   <echter@informatik.uni-rostock.de>
+ *         Stephen Rothwell
+ *    1.7: Modify driver's cached copy of the disabled/disengaged flags
+ *         to reflect current state of APM BIOS.
+ *         Chris Rankin <rankinc@bellsouth.net>
+ *         Reset interrupt 0 timer to 100Hz after suspend
+ *         Chad Miller <cmiller@surfsouth.com>
+ *         Add CONFIG_APM_IGNORE_SUSPEND_BOUNCE
+ *         Richard Gooch <rgooch@atnf.csiro.au>
+ *         Allow boot time disabling of APM
+ *         Make boot messages far less verbose by default
+ *         Make asm safer
+ *         Stephen Rothwell
+ *    1.8: Add CONFIG_APM_RTC_IS_GMT
+ *         Richard Gooch <rgooch@atnf.csiro.au>
+ *         change APM_NOINTS to CONFIG_APM_ALLOW_INTS
+ *         remove dependency on CONFIG_PROC_FS
+ *         Stephen Rothwell
+ *    1.9: Fix small typo.  <laslo@wodip.opole.pl>
+ *         Try to cope with BIOS's that need to have all display
+ *         devices blanked and not just the first one.
+ *         Ross Paterson <ross@soi.city.ac.uk>
+ *         Fix segment limit setting it has always been wrong as
+ *         the segments needed to have byte granularity.
+ *         Mark a few things __init.
+ *         Add hack to allow power off of SMP systems by popular request.
+ *         Use CONFIG_SMP instead of __SMP__
+ *         Ignore BOUNCES for three seconds.
+ *         Stephen Rothwell
+ *   1.10: Fix for Thinkpad return code.
+ *         Merge 2.2 and 2.3 drivers.
+ *         Remove APM dependencies in arch/i386/kernel/process.c
+ *         Remove APM dependencies in drivers/char/sysrq.c
+ *         Reset time across standby.
+ *         Allow more inititialisation on SMP.
+ *         Remove CONFIG_APM_POWER_OFF and make it boot time
+ *         configurable (default on).
+ *         Make debug only a boot time parameter (remove APM_DEBUG).
+ *         Try to blank all devices on any error.
+ *   1.11: Remove APM dependencies in drivers/char/console.c
+ *         Check nr_running to detect if we are idle (from
+ *         Borislav Deianov <borislav@lix.polytechnique.fr>)
+ *         Fix for bioses that don't zero the top part of the
+ *         entrypoint offset (Mario Sitta <sitta@al.unipmn.it>)
+ *         (reported by Panos Katsaloulis <teras@writeme.com>).
+ *         Real mode power off patch (Walter Hofmann
+ *         <Walter.Hofmann@physik.stud.uni-erlangen.de>).
+ *   1.12: Remove CONFIG_SMP as the compiler will optimize
+ *         the code away anyway (smp_num_cpus == 1 in UP)
+ *         noted by Artur Skawina <skawina@geocities.com>.
+ *         Make power off under SMP work again.
+ *         Fix thinko with initial engaging of BIOS.
+ *         Make sure power off only happens on CPU 0
+ *         (Paul "Rusty" Russell <rusty@rustcorp.com.au>).
+ *         Do error notification to user mode if BIOS calls fail.
+ *         Move entrypoint offset fix to ...boot/setup.S
+ *         where it belongs (Cosmos <gis88564@cis.nctu.edu.tw>).
+ *         Remove smp-power-off. SMP users must now specify
+ *         "apm=power-off" on the kernel command line. Suggested
+ *         by Jim Avera <jima@hal.com>, modified by Alan Cox
+ *         <alan@lxorguk.ukuu.org.uk>.
+ *         Register the /proc/apm entry even on SMP so that
+ *         scripts that check for it before doing power off
+ *         work (Jim Avera <jima@hal.com>).
+ *   1.13: Changes for new pm_ interfaces (Andy Henroid
+ *         <andy_henroid@yahoo.com>).
+ *         Modularize the code.
+ *         Fix the Thinkpad (again) :-( (CONFIG_APM_IGNORE_MULTIPLE_SUSPENDS
+ *         is now the way life works).
+ *         Fix thinko in suspend() (wrong return).
+ *         Notify drivers on critical suspend.
+ *         Make kapmd absorb more idle time (Pavel Machek <pavel@suse.cz>
+ *         modified by sfr).
+ *         Disable interrupts while we are suspended (Andy Henroid
+ *         <andy_henroid@yahoo.com> fixed by sfr).
+ *         Make power off work on SMP again (Tony Hoyle
+ *         <tmh@magenta-logic.com> and <zlatko@iskon.hr>) modified by sfr.
+ *         Remove CONFIG_APM_SUSPEND_BOUNCE.  The bounce ignore
+ *         interval is now configurable.
+ *   1.14: Make connection version persist across module unload/load.
+ *         Enable and engage power management earlier.
+ *         Disengage power management on module unload.
+ *         Changed to use the sysrq-register hack for registering the
+ *         power off function called by magic sysrq based upon discussions
+ *         in irc://irc.openprojects.net/#kernelnewbies
+ *         (Crutcher Dunnavant <crutcher+kernel@datastacks.com>).
+ *         Make CONFIG_APM_REAL_MODE_POWER_OFF run time configurable.
+ *         (Arjan van de Ven <arjanv@redhat.com>) modified by sfr.
+ *         Work around byte swap bug in one of the Vaio's BIOS's
+ *         (Marc Boucher <marc@mbsi.ca>).
+ *         Exposed the disable flag to dmi so that we can handle known
+ *         broken APM (Alan Cox <alan@redhat.com>).
+ *   1.14ac: If the BIOS says "I slowed the CPU down" then don't spin
+ *         calling it - instead idle. (Alan Cox <alan@redhat.com>)
+ *         If an APM idle fails log it and idle sensibly
+ *   1.15: Don't queue events to clients who open the device O_WRONLY.
+ *         Don't expect replies from clients who open the device O_RDONLY.
+ *         (Idea from Thomas Hood)
+ *         Minor waitqueue cleanups. (John Fremlin <chief@bandits.org>)
+ *   1.16: Fix idle calling. (Andreas Steinmetz <ast@domdv.de> et al.)
+ *         Notify listeners of standby or suspend events before notifying
+ *         drivers. Return EBUSY to ioctl() if suspend is rejected.
+ *         (Russell King <rmk@arm.linux.org.uk> and Thomas Hood)
+ *         Ignore first resume after we generate our own resume event
+ *         after a suspend (Thomas Hood)
+ *         Daemonize now gets rid of our controlling terminal (sfr).
+ *         CONFIG_APM_CPU_IDLE now just affects the default value of
+ *         idle_threshold (sfr).
+ *         Change name of kernel apm daemon (as it no longer idles) (sfr).
+ *   1.16ac: Fix up SMP support somewhat. You can now force SMP on and we
+ *	   make _all_ APM calls on the CPU#0. Fix unsafe sign bug.
+ *	   TODO: determine if its "boot CPU" or "CPU0" we want to lock to.
+ *
+ * APM 1.1 Reference:
+ *
+ *   Intel Corporation, Microsoft Corporation. Advanced Power Management
+ *   (APM) BIOS Interface Specification, Revision 1.1, September 1993.
+ *   Intel Order Number 241704-001.  Microsoft Part Number 781-110-X01.
+ *
+ * [This document is available free from Intel by calling 800.628.8686 (fax
+ * 916.356.6100) or 800.548.4725; or via anonymous ftp from
+ * ftp://ftp.intel.com/pub/IAL/software_specs/apmv11.doc.  It is also
+ * available from Microsoft by calling 206.882.8080.]
+ *
+ * APM 1.2 Reference:
+ *   Intel Corporation, Microsoft Corporation. Advanced Power Management
+ *   (APM) BIOS Interface Specification, Revision 1.2, February 1996.
+ *
+ * [This document is available from Microsoft at:
+ *    http://www.microsoft.com/hwdev/busbios/amp_12.htm]
+ */
+
+#include <linux/config.h>
+#include <linux/module.h>
+
+#include <linux/poll.h>
+#include <linux/types.h>
+#include <linux/stddef.h>
+#include <linux/timer.h>
+#include <linux/fcntl.h>
+#include <linux/slab.h>
+#include <linux/stat.h>
+#include <linux/proc_fs.h>
+#include <linux/miscdevice.h>
+#include <linux/apm_bios.h>
+#include <linux/init.h>
+#include <linux/time.h>
+#include <linux/sched.h>
+#include <linux/pm.h>
+#include <linux/device.h>
+#include <linux/kernel.h>
+#include <linux/smp.h>
+#include <linux/smp_lock.h>
+#include <linux/dmi.h>
+#include <linux/suspend.h>
+
+#include <asm/system.h>
+#include <asm/uaccess.h>
+#include <asm/desc.h>
+
+#include "io_ports.h"
+
+extern spinlock_t i8253_lock;
+extern unsigned long get_cmos_time(void);
+extern void machine_real_restart(unsigned char *, int);
+
+#if defined(CONFIG_APM_DISPLAY_BLANK) && defined(CONFIG_VT)
+extern int (*console_blank_hook)(int);
+#endif
+
+/*
+ * The apm_bios device is one of the misc char devices.
+ * This is its minor number.
+ */
+#define	APM_MINOR_DEV	134
+
+/*
+ * See Documentation/Config.help for the configuration options.
+ *
+ * Various options can be changed at boot time as follows:
+ * (We allow underscores for compatibility with the modules code)
+ *	apm=on/off			enable/disable APM
+ *	    [no-]allow[-_]ints		allow interrupts during BIOS calls
+ *	    [no-]broken[-_]psr		BIOS has a broken GetPowerStatus call
+ *	    [no-]realmode[-_]power[-_]off	switch to real mode before
+ *	    					powering off
+ *	    [no-]debug			log some debugging messages
+ *	    [no-]power[-_]off		power off on shutdown
+ *	    [no-]smp			Use apm even on an SMP box
+ *	    bounce[-_]interval=<n>	number of ticks to ignore suspend
+ *	    				bounces
+ *          idle[-_]threshold=<n>       System idle percentage above which to
+ *                                      make APM BIOS idle calls. Set it to
+ *                                      100 to disable.
+ *          idle[-_]period=<n>          Period (in 1/100s of a second) over
+ *                                      which the idle percentage is
+ *                                      calculated.
+ */
+
+/* KNOWN PROBLEM MACHINES:
+ *
+ * U: TI 4000M TravelMate: BIOS is *NOT* APM compliant
+ *                         [Confirmed by TI representative]
+ * ?: ACER 486DX4/75: uses dseg 0040, in violation of APM specification
+ *                    [Confirmed by BIOS disassembly]
+ *                    [This may work now ...]
+ * P: Toshiba 1950S: battery life information only gets updated after resume
+ * P: Midwest Micro Soundbook Elite DX2/66 monochrome: screen blanking
+ * 	broken in BIOS [Reported by Garst R. Reese <reese@isn.net>]
+ * ?: AcerNote-950: oops on reading /proc/apm - workaround is a WIP
+ * 	Neale Banks <neale@lowendale.com.au> December 2000
+ *
+ * Legend: U = unusable with APM patches
+ *         P = partially usable with APM patches
+ */
+
+/*
+ * Define as 1 to make the driver always call the APM BIOS busy
+ * routine even if the clock was not reported as slowed by the
+ * idle routine.  Otherwise, define as 0.
+ */
+#define ALWAYS_CALL_BUSY   1
+
+/*
+ * Define to make the APM BIOS calls zero all data segment registers (so
+ * that an incorrect BIOS implementation will cause a kernel panic if it
+ * tries to write to arbitrary memory).
+ */
+#define APM_ZERO_SEGS
+
+#include "apm.h"
+
+/*
+ * Define to make all _set_limit calls use 64k limits.  The APM 1.1 BIOS is
+ * supposed to provide limit information that it recognizes.  Many machines
+ * do this correctly, but many others do not restrict themselves to their
+ * claimed limit.  When this happens, they will cause a segmentation
+ * violation in the kernel at boot time.  Most BIOS's, however, will
+ * respect a 64k limit, so we use that.  If you want to be pedantic and
+ * hold your BIOS to its claims, then undefine this.
+ */
+#define APM_RELAX_SEGMENTS
+
+/*
+ * Define to re-initialize the interrupt 0 timer to 100 Hz after a suspend.
+ * This patched by Chad Miller <cmiller@surfsouth.com>, original code by
+ * David Chen <chen@ctpa04.mit.edu>
+ */
+#undef INIT_TIMER_AFTER_SUSPEND
+
+#ifdef INIT_TIMER_AFTER_SUSPEND
+#include <linux/timex.h>
+#include <asm/io.h>
+#include <linux/delay.h>
+#endif
+
+/*
+ * Need to poll the APM BIOS every second
+ */
+#define APM_CHECK_TIMEOUT	(HZ)
+
+/*
+ * Ignore suspend events for this amount of time after a resume
+ */
+#define DEFAULT_BOUNCE_INTERVAL		(3 * HZ)
+
+/*
+ * Maximum number of events stored
+ */
+#define APM_MAX_EVENTS		20
+
+/*
+ * The per-file APM data
+ */
+struct apm_user {
+	int		magic;
+	struct apm_user *	next;
+	int		suser: 1;
+	int		writer: 1;
+	int		reader: 1;
+	int		suspend_wait: 1;
+	int		suspend_result;
+	int		suspends_pending;
+	int		standbys_pending;
+	int		suspends_read;
+	int		standbys_read;
+	int		event_head;
+	int		event_tail;
+	apm_event_t	events[APM_MAX_EVENTS];
+};
+
+/*
+ * The magic number in apm_user
+ */
+#define APM_BIOS_MAGIC		0x4101
+
+/*
+ * idle percentage above which bios idle calls are done
+ */
+#ifdef CONFIG_APM_CPU_IDLE
+#define DEFAULT_IDLE_THRESHOLD	95
+#else
+#define DEFAULT_IDLE_THRESHOLD	100
+#endif
+#define DEFAULT_IDLE_PERIOD	(100 / 3)
+
+/*
+ * Local variables
+ */
+static struct {
+	unsigned long	offset;
+	unsigned short	segment;
+}				apm_bios_entry;
+static int			clock_slowed;
+static int			idle_threshold = DEFAULT_IDLE_THRESHOLD;
+static int			idle_period = DEFAULT_IDLE_PERIOD;
+static int			set_pm_idle;
+static int			suspends_pending;
+static int			standbys_pending;
+static int			ignore_sys_suspend;
+static int			ignore_normal_resume;
+static int			bounce_interval = DEFAULT_BOUNCE_INTERVAL;
+
+#ifdef CONFIG_APM_RTC_IS_GMT
+#	define	clock_cmos_diff	0
+#	define	got_clock_diff	1
+#else
+static long			clock_cmos_diff;
+static int			got_clock_diff;
+#endif
+static int			debug;
+static int			smp;
+static int			apm_disabled = -1;
+#ifdef CONFIG_SMP
+static int			power_off;
+#else
+static int			power_off = 1;
+#endif
+#ifdef CONFIG_APM_REAL_MODE_POWER_OFF
+static int			realmode_power_off = 1;
+#else
+static int			realmode_power_off;
+#endif
+static int			exit_kapmd;
+static int			kapmd_running;
+#ifdef CONFIG_APM_ALLOW_INTS
+static int			allow_ints = 1;
+#else
+static int			allow_ints;
+#endif
+static int			broken_psr;
+
+static DECLARE_WAIT_QUEUE_HEAD(apm_waitqueue);
+static DECLARE_WAIT_QUEUE_HEAD(apm_suspend_waitqueue);
+static struct apm_user *	user_list;
+static DEFINE_SPINLOCK(user_list_lock);
+static struct desc_struct	bad_bios_desc = { 0, 0x00409200 };
+
+static char			driver_version[] = "1.16ac";	/* no spaces */
+
+/*
+ *	APM event names taken from the APM 1.2 specification. These are
+ *	the message codes that the BIOS uses to tell us about events
+ */
+static char *	apm_event_name[] = {
+	"system standby",
+	"system suspend",
+	"normal resume",
+	"critical resume",
+	"low battery",
+	"power status change",
+	"update time",
+	"critical suspend",
+	"user standby",
+	"user suspend",
+	"system standby resume",
+	"capabilities change"
+};
+#define NR_APM_EVENT_NAME	\
+		(sizeof(apm_event_name) / sizeof(apm_event_name[0]))
+
+typedef struct lookup_t {
+	int	key;
+	char *	msg;
+} lookup_t;
+
+/*
+ *	The BIOS returns a set of standard error codes in AX when the
+ *	carry flag is set.
+ */
+ 
+static const lookup_t error_table[] = {
+/* N/A	{ APM_SUCCESS,		"Operation succeeded" }, */
+	{ APM_DISABLED,		"Power management disabled" },
+	{ APM_CONNECTED,	"Real mode interface already connected" },
+	{ APM_NOT_CONNECTED,	"Interface not connected" },
+	{ APM_16_CONNECTED,	"16 bit interface already connected" },
+/* N/A	{ APM_16_UNSUPPORTED,	"16 bit interface not supported" }, */
+	{ APM_32_CONNECTED,	"32 bit interface already connected" },
+	{ APM_32_UNSUPPORTED,	"32 bit interface not supported" },
+	{ APM_BAD_DEVICE,	"Unrecognized device ID" },
+	{ APM_BAD_PARAM,	"Parameter out of range" },
+	{ APM_NOT_ENGAGED,	"Interface not engaged" },
+	{ APM_BAD_FUNCTION,     "Function not supported" },
+	{ APM_RESUME_DISABLED,	"Resume timer disabled" },
+	{ APM_BAD_STATE,	"Unable to enter requested state" },
+/* N/A	{ APM_NO_EVENTS,	"No events pending" }, */
+	{ APM_NO_ERROR,		"BIOS did not set a return code" },
+	{ APM_NOT_PRESENT,	"No APM present" }
+};
+#define ERROR_COUNT	(sizeof(error_table)/sizeof(lookup_t))
+
+/**
+ *	apm_error	-	display an APM error
+ *	@str: information string
+ *	@err: APM BIOS return code
+ *
+ *	Write a meaningful log entry to the kernel log in the event of
+ *	an APM error.
+ */
+ 
+static void apm_error(char *str, int err)
+{
+	int	i;
+
+	for (i = 0; i < ERROR_COUNT; i++)
+		if (error_table[i].key == err) break;
+	if (i < ERROR_COUNT)
+		printk(KERN_NOTICE "apm: %s: %s\n", str, error_table[i].msg);
+	else
+		printk(KERN_NOTICE "apm: %s: unknown error code %#2.2x\n",
+			str, err);
+}
+
+/*
+ * Lock APM functionality to physical CPU 0
+ */
+ 
+#ifdef CONFIG_SMP
+
+static cpumask_t apm_save_cpus(void)
+{
+	cpumask_t x = current->cpus_allowed;
+	/* Some bioses don't like being called from CPU != 0 */
+	set_cpus_allowed(current, cpumask_of_cpu(0));
+	BUG_ON(smp_processor_id() != 0);
+	return x;
+}
+
+static inline void apm_restore_cpus(cpumask_t mask)
+{
+	set_cpus_allowed(current, mask);
+}
+
+#else
+
+/*
+ *	No CPU lockdown needed on a uniprocessor
+ */
+ 
+#define apm_save_cpus()		(current->cpus_allowed)
+#define apm_restore_cpus(x)	(void)(x)
+
+#endif
+
+/*
+ * These are the actual BIOS calls.  Depending on APM_ZERO_SEGS and
+ * apm_info.allow_ints, we are being really paranoid here!  Not only
+ * are interrupts disabled, but all the segment registers (except SS)
+ * are saved and zeroed this means that if the BIOS tries to reference
+ * any data without explicitly loading the segment registers, the kernel
+ * will fault immediately rather than have some unforeseen circumstances
+ * for the rest of the kernel.  And it will be very obvious!  :-) Doing
+ * this depends on CS referring to the same physical memory as DS so that
+ * DS can be zeroed before the call. Unfortunately, we can't do anything
+ * about the stack segment/pointer.  Also, we tell the compiler that
+ * everything could change.
+ *
+ * Also, we KNOW that for the non error case of apm_bios_call, there
+ * is no useful data returned in the low order 8 bits of eax.
+ */
+#define APM_DO_CLI	\
+	if (apm_info.allow_ints) \
+		local_irq_enable(); \
+	else \
+		local_irq_disable();
+
+#ifdef APM_ZERO_SEGS
+#	define APM_DECL_SEGS \
+		unsigned int saved_fs; unsigned int saved_gs;
+#	define APM_DO_SAVE_SEGS \
+		savesegment(fs, saved_fs); savesegment(gs, saved_gs)
+#	define APM_DO_RESTORE_SEGS \
+		loadsegment(fs, saved_fs); loadsegment(gs, saved_gs)
+#else
+#	define APM_DECL_SEGS
+#	define APM_DO_SAVE_SEGS
+#	define APM_DO_RESTORE_SEGS
+#endif
+
+/**
+ *	apm_bios_call	-	Make an APM BIOS 32bit call
+ *	@func: APM function to execute
+ *	@ebx_in: EBX register for call entry
+ *	@ecx_in: ECX register for call entry
+ *	@eax: EAX register return
+ *	@ebx: EBX register return
+ *	@ecx: ECX register return
+ *	@edx: EDX register return
+ *	@esi: ESI register return
+ *
+ *	Make an APM call using the 32bit protected mode interface. The
+ *	caller is responsible for knowing if APM BIOS is configured and
+ *	enabled. This call can disable interrupts for a long period of
+ *	time on some laptops.  The return value is in AH and the carry
+ *	flag is loaded into AL.  If there is an error, then the error
+ *	code is returned in AH (bits 8-15 of eax) and this function
+ *	returns non-zero.
+ */
+ 
+static u8 apm_bios_call(u32 func, u32 ebx_in, u32 ecx_in,
+	u32 *eax, u32 *ebx, u32 *ecx, u32 *edx, u32 *esi)
+{
+	APM_DECL_SEGS
+	unsigned long		flags;
+	cpumask_t		cpus;
+	int			cpu;
+	struct desc_struct	save_desc_40;
+
+	cpus = apm_save_cpus();
+	
+	cpu = get_cpu();
+	save_desc_40 = per_cpu(cpu_gdt_table, cpu)[0x40 / 8];
+	per_cpu(cpu_gdt_table, cpu)[0x40 / 8] = bad_bios_desc;
+
+	local_save_flags(flags);
+	APM_DO_CLI;
+	APM_DO_SAVE_SEGS;
+	apm_bios_call_asm(func, ebx_in, ecx_in, eax, ebx, ecx, edx, esi);
+	APM_DO_RESTORE_SEGS;
+	local_irq_restore(flags);
+	per_cpu(cpu_gdt_table, cpu)[0x40 / 8] = save_desc_40;
+	put_cpu();
+	apm_restore_cpus(cpus);
+	
+	return *eax & 0xff;
+}
+
+/**
+ *	apm_bios_call_simple	-	make a simple APM BIOS 32bit call
+ *	@func: APM function to invoke
+ *	@ebx_in: EBX register value for BIOS call
+ *	@ecx_in: ECX register value for BIOS call
+ *	@eax: EAX register on return from the BIOS call
+ *
+ *	Make a BIOS call that does only returns one value, or just status.
+ *	If there is an error, then the error code is returned in AH
+ *	(bits 8-15 of eax) and this function returns non-zero. This is
+ *	used for simpler BIOS operations. This call may hold interrupts
+ *	off for a long time on some laptops.
+ */
+
+static u8 apm_bios_call_simple(u32 func, u32 ebx_in, u32 ecx_in, u32 *eax)
+{
+	u8			error;
+	APM_DECL_SEGS
+	unsigned long		flags;
+	cpumask_t		cpus;
+	int			cpu;
+	struct desc_struct	save_desc_40;
+
+
+	cpus = apm_save_cpus();
+	
+	cpu = get_cpu();
+	save_desc_40 = per_cpu(cpu_gdt_table, cpu)[0x40 / 8];
+	per_cpu(cpu_gdt_table, cpu)[0x40 / 8] = bad_bios_desc;
+
+	local_save_flags(flags);
+	APM_DO_CLI;
+	APM_DO_SAVE_SEGS;
+	error = apm_bios_call_simple_asm(func, ebx_in, ecx_in, eax);
+	APM_DO_RESTORE_SEGS;
+	local_irq_restore(flags);
+	__get_cpu_var(cpu_gdt_table)[0x40 / 8] = save_desc_40;
+	put_cpu();
+	apm_restore_cpus(cpus);
+	return error;
+}
+
+/**
+ *	apm_driver_version	-	APM driver version
+ *	@val:	loaded with the APM version on return
+ *
+ *	Retrieve the APM version supported by the BIOS. This is only
+ *	supported for APM 1.1 or higher. An error indicates APM 1.0 is
+ *	probably present.
+ *
+ *	On entry val should point to a value indicating the APM driver
+ *	version with the high byte being the major and the low byte the
+ *	minor number both in BCD
+ *
+ *	On return it will hold the BIOS revision supported in the
+ *	same format.
+ */
+
+static int apm_driver_version(u_short *val)
+{
+	u32	eax;
+
+	if (apm_bios_call_simple(APM_FUNC_VERSION, 0, *val, &eax))
+		return (eax >> 8) & 0xff;
+	*val = eax;
+	return APM_SUCCESS;
+}
+
+/**
+ *	apm_get_event	-	get an APM event from the BIOS
+ *	@event: pointer to the event
+ *	@info: point to the event information
+ *
+ *	The APM BIOS provides a polled information for event
+ *	reporting. The BIOS expects to be polled at least every second
+ *	when events are pending. When a message is found the caller should
+ *	poll until no more messages are present.  However, this causes
+ *	problems on some laptops where a suspend event notification is
+ *	not cleared until it is acknowledged.
+ *
+ *	Additional information is returned in the info pointer, providing
+ *	that APM 1.2 is in use. If no messges are pending the value 0x80
+ *	is returned (No power management events pending).
+ */
+ 
+static int apm_get_event(apm_event_t *event, apm_eventinfo_t *info)
+{
+	u32	eax;
+	u32	ebx;
+	u32	ecx;
+	u32	dummy;
+
+	if (apm_bios_call(APM_FUNC_GET_EVENT, 0, 0, &eax, &ebx, &ecx,
+			&dummy, &dummy))
+		return (eax >> 8) & 0xff;
+	*event = ebx;
+	if (apm_info.connection_version < 0x0102)
+		*info = ~0; /* indicate info not valid */
+	else
+		*info = ecx;
+	return APM_SUCCESS;
+}
+
+/**
+ *	set_power_state	-	set the power management state
+ *	@what: which items to transition
+ *	@state: state to transition to
+ *
+ *	Request an APM change of state for one or more system devices. The
+ *	processor state must be transitioned last of all. what holds the
+ *	class of device in the upper byte and the device number (0xFF for
+ *	all) for the object to be transitioned.
+ *
+ *	The state holds the state to transition to, which may in fact
+ *	be an acceptance of a BIOS requested state change.
+ */
+ 
+static int set_power_state(u_short what, u_short state)
+{
+	u32	eax;
+
+	if (apm_bios_call_simple(APM_FUNC_SET_STATE, what, state, &eax))
+		return (eax >> 8) & 0xff;
+	return APM_SUCCESS;
+}
+
+/**
+ *	set_system_power_state - set system wide power state
+ *	@state: which state to enter
+ *
+ *	Transition the entire system into a new APM power state.
+ */
+ 
+static int set_system_power_state(u_short state)
+{
+	return set_power_state(APM_DEVICE_ALL, state);
+}
+
+/**
+ *	apm_do_idle	-	perform power saving
+ *
+ *	This function notifies the BIOS that the processor is (in the view
+ *	of the OS) idle. It returns -1 in the event that the BIOS refuses
+ *	to handle the idle request. On a success the function returns 1
+ *	if the BIOS did clock slowing or 0 otherwise.
+ */
+ 
+static int apm_do_idle(void)
+{
+	u32	eax;
+
+	if (apm_bios_call_simple(APM_FUNC_IDLE, 0, 0, &eax)) {
+		static unsigned long t;
+
+		/* This always fails on some SMP boards running UP kernels.
+		 * Only report the failure the first 5 times.
+		 */
+		if (++t < 5)
+		{
+			printk(KERN_DEBUG "apm_do_idle failed (%d)\n",
+					(eax >> 8) & 0xff);
+			t = jiffies;
+		}
+		return -1;
+	}
+	clock_slowed = (apm_info.bios.flags & APM_IDLE_SLOWS_CLOCK) != 0;
+	return clock_slowed;
+}
+
+/**
+ *	apm_do_busy	-	inform the BIOS the CPU is busy
+ *
+ *	Request that the BIOS brings the CPU back to full performance. 
+ */
+ 
+static void apm_do_busy(void)
+{
+	u32	dummy;
+
+	if (clock_slowed || ALWAYS_CALL_BUSY) {
+		(void) apm_bios_call_simple(APM_FUNC_BUSY, 0, 0, &dummy);
+		clock_slowed = 0;
+	}
+}
+
+/*
+ * If no process has really been interested in
+ * the CPU for some time, we want to call BIOS
+ * power management - we probably want
+ * to conserve power.
+ */
+#define IDLE_CALC_LIMIT   (HZ * 100)
+#define IDLE_LEAKY_MAX    16
+
+static void (*original_pm_idle)(void);
+
+extern void default_idle(void);
+
+/**
+ * apm_cpu_idle		-	cpu idling for APM capable Linux
+ *
+ * This is the idling function the kernel executes when APM is available. It 
+ * tries to do BIOS powermanagement based on the average system idle time.
+ * Furthermore it calls the system default idle routine.
+ */
+
+static void apm_cpu_idle(void)
+{
+	static int use_apm_idle; /* = 0 */
+	static unsigned int last_jiffies; /* = 0 */
+	static unsigned int last_stime; /* = 0 */
+
+	int apm_idle_done = 0;
+	unsigned int jiffies_since_last_check = jiffies - last_jiffies;
+	unsigned int bucket;
+
+recalc:
+	if (jiffies_since_last_check > IDLE_CALC_LIMIT) {
+		use_apm_idle = 0;
+		last_jiffies = jiffies;
+		last_stime = current->stime;
+	} else if (jiffies_since_last_check > idle_period) {
+		unsigned int idle_percentage;
+
+		idle_percentage = current->stime - last_stime;
+		idle_percentage *= 100;
+		idle_percentage /= jiffies_since_last_check;
+		use_apm_idle = (idle_percentage > idle_threshold);
+		if (apm_info.forbid_idle)
+			use_apm_idle = 0;
+		last_jiffies = jiffies;
+		last_stime = current->stime;
+	}
+
+	bucket = IDLE_LEAKY_MAX;
+
+	while (!need_resched()) {
+		if (use_apm_idle) {
+			unsigned int t;
+
+			t = jiffies;
+			switch (apm_do_idle()) {
+			case 0: apm_idle_done = 1;
+				if (t != jiffies) {
+					if (bucket) {
+						bucket = IDLE_LEAKY_MAX;
+						continue;
+					}
+				} else if (bucket) {
+					bucket--;
+					continue;
+				}
+				break;
+			case 1: apm_idle_done = 1;
+				break;
+			default: /* BIOS refused */
+				break;
+			}
+		}
+		if (original_pm_idle)
+			original_pm_idle();
+		else
+			default_idle();
+		jiffies_since_last_check = jiffies - last_jiffies;
+		if (jiffies_since_last_check > idle_period)
+			goto recalc;
+	}
+
+	if (apm_idle_done)
+		apm_do_busy();
+}
+
+/**
+ *	apm_power_off	-	ask the BIOS to power off
+ *
+ *	Handle the power off sequence. This is the one piece of code we
+ *	will execute even on SMP machines. In order to deal with BIOS
+ *	bugs we support real mode APM BIOS power off calls. We also make
+ *	the SMP call on CPU0 as some systems will only honour this call
+ *	on their first cpu.
+ */
+ 
+static void apm_power_off(void)
+{
+	unsigned char	po_bios_call[] = {
+		0xb8, 0x00, 0x10,	/* movw  $0x1000,ax  */
+		0x8e, 0xd0,		/* movw  ax,ss       */
+		0xbc, 0x00, 0xf0,	/* movw  $0xf000,sp  */
+		0xb8, 0x07, 0x53,	/* movw  $0x5307,ax  */
+		0xbb, 0x01, 0x00,	/* movw  $0x0001,bx  */
+		0xb9, 0x03, 0x00,	/* movw  $0x0003,cx  */
+		0xcd, 0x15		/* int   $0x15       */
+	};
+
+	/*
+	 * This may be called on an SMP machine.
+	 */
+#ifdef CONFIG_SMP
+	/* Some bioses don't like being called from CPU != 0 */
+	set_cpus_allowed(current, cpumask_of_cpu(0));
+	BUG_ON(smp_processor_id() != 0);
+#endif
+	if (apm_info.realmode_power_off)
+	{
+		(void)apm_save_cpus();
+		machine_real_restart(po_bios_call, sizeof(po_bios_call));
+	}
+	else
+		(void) set_system_power_state(APM_STATE_OFF);
+}
+
+#ifdef CONFIG_APM_DO_ENABLE
+
+/**
+ *	apm_enable_power_management - enable BIOS APM power management
+ *	@enable: enable yes/no
+ *
+ *	Enable or disable the APM BIOS power services. 
+ */
+ 
+static int apm_enable_power_management(int enable)
+{
+	u32	eax;
+
+	if ((enable == 0) && (apm_info.bios.flags & APM_BIOS_DISENGAGED))
+		return APM_NOT_ENGAGED;
+	if (apm_bios_call_simple(APM_FUNC_ENABLE_PM, APM_DEVICE_BALL,
+			enable, &eax))
+		return (eax >> 8) & 0xff;
+	if (enable)
+		apm_info.bios.flags &= ~APM_BIOS_DISABLED;
+	else
+		apm_info.bios.flags |= APM_BIOS_DISABLED;
+	return APM_SUCCESS;
+}
+#endif
+
+/**
+ *	apm_get_power_status	-	get current power state
+ *	@status: returned status
+ *	@bat: battery info
+ *	@life: estimated life
+ *
+ *	Obtain the current power status from the APM BIOS. We return a
+ *	status which gives the rough battery status, and current power
+ *	source. The bat value returned give an estimate as a percentage
+ *	of life and a status value for the battery. The estimated life
+ *	if reported is a lifetime in secodnds/minutes at current powwer
+ *	consumption.
+ */
+ 
+static int apm_get_power_status(u_short *status, u_short *bat, u_short *life)
+{
+	u32	eax;
+	u32	ebx;
+	u32	ecx;
+	u32	edx;
+	u32	dummy;
+
+	if (apm_info.get_power_status_broken)
+		return APM_32_UNSUPPORTED;
+	if (apm_bios_call(APM_FUNC_GET_STATUS, APM_DEVICE_ALL, 0,
+			&eax, &ebx, &ecx, &edx, &dummy))
+		return (eax >> 8) & 0xff;
+	*status = ebx;
+	*bat = ecx;
+	if (apm_info.get_power_status_swabinminutes) {
+		*life = swab16((u16)edx);
+		*life |= 0x8000;
+	} else
+		*life = edx;
+	return APM_SUCCESS;
+}
+
+#if 0
+static int apm_get_battery_status(u_short which, u_short *status,
+				  u_short *bat, u_short *life, u_short *nbat)
+{
+	u32	eax;
+	u32	ebx;
+	u32	ecx;
+	u32	edx;
+	u32	esi;
+
+	if (apm_info.connection_version < 0x0102) {
+		/* pretend we only have one battery. */
+		if (which != 1)
+			return APM_BAD_DEVICE;
+		*nbat = 1;
+		return apm_get_power_status(status, bat, life);
+	}
+
+	if (apm_bios_call(APM_FUNC_GET_STATUS, (0x8000 | (which)), 0, &eax,
+			&ebx, &ecx, &edx, &esi))
+		return (eax >> 8) & 0xff;
+	*status = ebx;
+	*bat = ecx;
+	*life = edx;
+	*nbat = esi;
+	return APM_SUCCESS;
+}
+#endif
+
+/**
+ *	apm_engage_power_management	-	enable PM on a device
+ *	@device: identity of device
+ *	@enable: on/off
+ *
+ *	Activate or deactive power management on either a specific device
+ *	or the entire system (%APM_DEVICE_ALL).
+ */
+ 
+static int apm_engage_power_management(u_short device, int enable)
+{
+	u32	eax;
+
+	if ((enable == 0) && (device == APM_DEVICE_ALL)
+	    && (apm_info.bios.flags & APM_BIOS_DISABLED))
+		return APM_DISABLED;
+	if (apm_bios_call_simple(APM_FUNC_ENGAGE_PM, device, enable, &eax))
+		return (eax >> 8) & 0xff;
+	if (device == APM_DEVICE_ALL) {
+		if (enable)
+			apm_info.bios.flags &= ~APM_BIOS_DISENGAGED;
+		else
+			apm_info.bios.flags |= APM_BIOS_DISENGAGED;
+	}
+	return APM_SUCCESS;
+}
+
+#if defined(CONFIG_APM_DISPLAY_BLANK) && defined(CONFIG_VT)
+
+/**
+ *	apm_console_blank	-	blank the display
+ *	@blank: on/off
+ *
+ *	Att