patch-2.1.122 linux/arch/i386/kernel/apm.c
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- Lines: 1346
- Date:
Sun Sep 13 12:16:22 1998
- Orig file:
v2.1.121/linux/arch/i386/kernel/apm.c
- Orig date:
Wed Dec 31 16:00:00 1969
diff -u --recursive --new-file v2.1.121/linux/arch/i386/kernel/apm.c linux/arch/i386/kernel/apm.c
@@ -0,0 +1,1345 @@
+/* -*- linux-c -*-
+ * APM BIOS driver for Linux
+ * Copyright 1994-1998 Stephen Rothwell
+ * (Stephen.Rothwell@canb.auug.org.au)
+ *
+ * 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 (Stephen.Rothwell@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
+ *
+ * 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
+ *
+ * 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 Intel at:
+ * http://www.intel.com/IAL/powermgm
+ * or Microsoft at
+ * http://www.microsoft.com/windows/thirdparty/hardware/pcfuture.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/malloc.h>
+#include <linux/linkage.h>
+#ifdef CONFIG_PROC_FS
+#include <linux/stat.h>
+#include <linux/proc_fs.h>
+#endif
+#include <linux/miscdevice.h>
+#include <linux/apm_bios.h>
+#include <linux/init.h>
+
+#include <asm/system.h>
+#include <asm/uaccess.h>
+#include <asm/desc.h>
+
+EXPORT_SYMBOL(apm_register_callback);
+EXPORT_SYMBOL(apm_unregister_callback);
+
+extern unsigned long get_cmos_time(void);
+
+/*
+ * The apm_bios device is one of the misc char devices.
+ * This is its minor number.
+ */
+#define APM_MINOR_DEV 134
+
+/* Configurable options:
+ *
+ * CONFIG_APM_IGNORE_USER_SUSPEND: define to ignore USER SUSPEND requests.
+ * This is necessary on the NEC Versa M series, which generates these when
+ * resuming from SYSTEM SUSPEND. However, enabling this on other laptops
+ * will cause the laptop to generate a CRITICAL SUSPEND when an appropriate
+ * USER SUSPEND is ignored -- this may prevent the APM driver from updating
+ * the system time on a RESUME.
+ *
+ * CONFIG_APM_DO_ENABLE: enable APM features at boot time. From page 36 of
+ * the specification: "When disabled, the APM BIOS does not automatically
+ * power manage devices, enter the Standby State, enter the Suspend State,
+ * or take power saving steps in response to CPU Idle calls." This driver
+ * will make CPU Idle calls when Linux is idle (unless this feature is
+ * turned off -- see below). This should always save battery power, but
+ * more complicated APM features will be dependent on your BIOS
+ * implementation. You may need to turn this option off if your computer
+ * hangs at boot time when using APM support, or if it beeps continuously
+ * instead of suspending. Turn this off if you have a NEC UltraLite Versa
+ * 33/C or a Toshiba T400CDT. This is off by default since most machines
+ * do fine without this feature.
+ *
+ * CONFIG_APM_CPU_IDLE: enable calls to APM CPU Idle/CPU Busy inside the
+ * idle loop. On some machines, this can activate improved power savings,
+ * such as a slowed CPU clock rate, when the machine is idle. These idle
+ * call is made after the idle loop has run for some length of time (e.g.,
+ * 333 mS). On some machines, this will cause a hang at boot time or
+ * whenever the CPU becomes idle.
+ *
+ * CONFIG_APM_DISPLAY_BLANK: enable console blanking using the APM. Some
+ * laptops can use this to turn of the LCD backlight when the VC screen
+ * blanker blanks the screen. Note that this is only used by the VC screen
+ * blanker, and probably won't turn off the backlight when using X11. Some
+ * problems have been reported when using this option with gpm (if you'd
+ * like to debug this, please do so).
+ *
+ * CONFIG_APM_IGNORE_MULTIPLE_SUSPEND: The IBM TP560 bios seems to insist
+ * on returning multiple suspend/standby events whenever one occurs. We
+ * really only need one at a time, so just ignore any beyond the first.
+ * This is probably safe on most laptops.
+ *
+ * If you are debugging the APM support for your laptop, note that code for
+ * all of these options is contained in this file, so you can #define or
+ * #undef these on the next line to avoid recompiling the whole kernel.
+ *
+ */
+
+/* KNOWN PROBLEM MACHINES:
+ *
+ * U: TI 4000M TravelMate: BIOS is *NOT* APM compliant
+ * [Confirmed by TI representative]
+ * U: 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>]
+ *
+ * Legend: U = unusable with APM patches
+ * P = partially usable with APM patches
+ */
+
+/*
+ * Define to have debug messages.
+ */
+#undef APM_DEBUG
+
+/*
+ * Define to always call the APM BIOS busy routine even if the clock was
+ * not slowed by the idle routine.
+ */
+#define ALWAYS_CALL_BUSY
+
+/*
+ * Define to disable interrupts in APM BIOS calls (the CPU Idle BIOS call
+ * should turn interrupts on before it does a 'hlt').
+ * This reportedly needs undefining for the ThinkPad 600.
+ */
+#define APM_NOINTS
+
+/*
+ * 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
+
+/*
+ * 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
+
+/*
+ * Need to poll the APM BIOS every second
+ */
+#define APM_CHECK_TIMEOUT (HZ)
+
+/*
+ * Save a segment register away
+ */
+#define savesegment(seg, where) __asm__ __volatile__("movl %%" #seg ",%0" : "=m" (where))
+
+/*
+ * Forward declarations
+ */
+static void suspend(void);
+static void standby(void);
+static void set_time(void);
+
+static void check_events(void);
+static void do_apm_timer(unsigned long);
+
+static int do_open(struct inode *, struct file *);
+static int do_release(struct inode *, struct file *);
+static ssize_t do_read(struct file *, char *, size_t , loff_t *);
+static unsigned int do_poll(struct file *, poll_table *);
+static int do_ioctl(struct inode *, struct file *, u_int, u_long);
+
+#ifdef CONFIG_PROC_FS
+static int apm_get_info(char *, char **, off_t, int, int);
+#endif
+
+extern int apm_register_callback(int (*)(apm_event_t));
+extern void apm_unregister_callback(int (*)(apm_event_t));
+
+/*
+ * Local variables
+ */
+static asmlinkage struct {
+ unsigned long offset;
+ unsigned short segment;
+} apm_bios_entry;
+static int apm_enabled = 0;
+#ifdef CONFIG_APM_CPU_IDLE
+static int clock_slowed = 0;
+#endif
+static int suspends_pending = 0;
+static int standbys_pending = 0;
+#ifdef CONFIG_APM_IGNORE_MULTIPLE_SUSPEND
+static int waiting_for_resume = 0;
+#endif
+
+static long clock_cmos_diff;
+static int got_clock_diff = 0;
+
+static struct wait_queue * process_list = NULL;
+static struct apm_bios_struct * user_list = NULL;
+
+static struct timer_list apm_timer;
+
+static char driver_version[] = "1.5"; /* no spaces */
+
+#ifdef APM_DEBUG
+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]))
+#endif
+
+static struct file_operations apm_bios_fops = {
+ NULL, /* lseek */
+ do_read,
+ NULL, /* write */
+ NULL, /* readdir */
+ do_poll,
+ do_ioctl,
+ NULL, /* mmap */
+ do_open,
+ NULL, /* flush */
+ do_release,
+ NULL, /* fsync */
+ NULL /* fasync */
+};
+
+static struct miscdevice apm_device = {
+ APM_MINOR_DEV,
+ "apm",
+ &apm_bios_fops
+};
+
+typedef struct callback_list_t {
+ int (* callback)(apm_event_t);
+ struct callback_list_t * next;
+} callback_list_t;
+
+static callback_list_t * callback_list = NULL;
+
+typedef struct lookup_t {
+ int key;
+ char * msg;
+} lookup_t;
+
+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_NOT_PRESENT, "No APM present" }
+};
+#define ERROR_COUNT (sizeof(error_table)/sizeof(lookup_t))
+
+/*
+ * These are the actual BIOS calls. Depending on APM_ZERO_SEGS
+ * and APM_NOINTS, 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.
+ */
+
+static inline int apm_bios_call(u32 eax_in, u32 ebx_in, u32 ecx_in,
+ u32 *eax, u32 *ebx, u32 *ecx, u32 *edx, u32 *esi)
+{
+ unsigned int old_fs, old_gs;
+ int error;
+
+#ifdef APM_ZERO_SEGS
+ savesegment(fs, old_fs);
+ savesegment(gs, old_gs);
+#endif
+ __asm__ __volatile__(
+ "pushfl\n\t"
+#ifdef APM_NOINTS
+ "cli\n\t"
+#endif
+#ifdef APM_ZERO_SEGS
+ "pushl %%ds\n\t"
+ "pushl %%es\n\t"
+ "movl %w9,%%ds\n\t"
+ "movl %w9,%%es\n\t"
+ "movl %w9,%%fs\n\t"
+ "movl %w9,%%gs\n\t"
+#endif
+ "lcall %%cs:" SYMBOL_NAME_STR(apm_bios_entry) "\n\t"
+ "movl $0, %%edi\n\t"
+ "jnc 1f\n\t"
+ "movl $1, %%edi\n"
+ "1:\tpopl %%es\n\t"
+ "popl %%ds\n\t"
+ "popfl\n\t"
+ : "=a" (*eax), "=b" (*ebx), "=c" (*ecx), "=d" (*edx),
+ "=S" (*esi), "=D" (error)
+ : "a" (eax_in), "b" (ebx_in), "c" (ecx_in)
+#ifdef APM_ZERO_SEGS
+ , "r" (0)
+#endif
+ : "ax", "bx", "cx", "dx", "si", "di", "bp", "memory");
+#ifdef APM_ZERO_SEGS
+ loadsegment(fs, old_fs);
+ loadsegment(gs, old_gs);
+#endif
+ return error;
+}
+
+/*
+ * This version only returns one value (usually an error code)
+ */
+
+static inline int apm_bios_call_simple(u32 eax_in, u32 ebx_in, u32 ecx_in, u32 *eax)
+{
+ unsigned int old_fs, old_gs;
+ int error;
+
+#ifdef APM_ZERO_SEGS
+ savesegment(fs, old_fs);
+ savesegment(gs, old_gs);
+#endif
+ __asm__ __volatile__(
+ "pushfl\n\t"
+#ifdef APM_NOINTS
+ "cli\n\t"
+#endif
+#ifdef APM_ZERO_SEGS
+ "pushl %%ds\n\t"
+ "pushl %%es\n\t"
+ "movl %w5,%%ds\n\t"
+ "movl %w5,%%es\n\t"
+ "movl %w5,%%fs\n\t"
+ "movl %w5,%%gs\n\t"
+#endif
+ "lcall %%cs:" SYMBOL_NAME_STR(apm_bios_entry) "\n\t"
+ "movl $0, %%edi\n\t"
+ "jnc 1f\n\t"
+ "movl $1, %%edi\n"
+ "1:\tpopl %%es\n\t"
+ "popl %%ds\n\t"
+ "popfl\n\t"
+ : "=a" (*eax), "=D" (error)
+ : "a" (eax_in), "b" (ebx_in), "c" (ecx_in)
+#ifdef APM_ZERO_SEGS
+ , "r" (0)
+#endif
+ : "ax", "bx", "cx", "dx", "si", "di", "bp", "memory");
+#ifdef APM_ZERO_SEGS
+ loadsegment(fs, old_fs);
+ loadsegment(gs, old_gs);
+#endif
+ return error;
+}
+
+static int apm_driver_version(u_short *val)
+{
+ int error;
+ u32 eax;
+
+ error = apm_bios_call_simple(0x530e, 0, *val, &eax);
+ if (error)
+ return (eax >> 8) & 0xff;
+ *val = eax;
+ return APM_SUCCESS;
+}
+
+static int apm_get_event(apm_event_t *event, apm_eventinfo_t *info)
+{
+ int error;
+ u32 eax;
+ u32 ebx;
+ u32 ecx;
+ u32 dummy;
+
+ error = apm_bios_call(0x530b, 0, 0, &eax, &ebx, &ecx, &dummy, &dummy);
+ if (error)
+ return (eax >> 8) & 0xff;
+ *event = ebx;
+ if (apm_bios_info.version < 0x0102)
+ *info = ~0; /* indicate info not valid */
+ else
+ *info = ecx;
+ return APM_SUCCESS;
+}
+
+static int set_power_state(u_short what, u_short state)
+{
+ int error;
+ u32 eax;
+
+ error = apm_bios_call_simple(0x5307, what, state, &eax);
+ if (error)
+ return (eax >> 8) & 0xff;
+ return APM_SUCCESS;
+}
+
+int apm_set_power_state(u_short state)
+{
+ return set_power_state(0x0001, state);
+}
+
+#ifdef CONFIG_APM_DISPLAY_BLANK
+/* Called by apm_display_blank and apm_display_unblank when apm_enabled. */
+static int apm_set_display_power_state(u_short state)
+{
+ return set_power_state(0x01ff, state);
+}
+#endif
+
+#ifdef CONFIG_APM_DO_ENABLE
+/* Called by apm_setup if apm_enabled will be true. */
+static int apm_enable_power_management(void)
+{
+ int error;
+ u32 eax;
+
+ error = apm_bios_call_simple(0x5308,
+ (apm_bios_info.version > 0x100) ? 0x0001 : 0xffff, 1, &eax);
+ if (error)
+ return (eax >> 8) & 0xff;
+ return APM_SUCCESS;
+}
+#endif
+
+static int apm_get_power_status(u_short *status, u_short *bat, u_short *life)
+{
+ int error;
+ u32 eax;
+ u32 ebx;
+ u32 ecx;
+ u32 edx;
+ u32 dummy;
+
+ error = apm_bios_call(0x530a, 1, 0, &eax, &ebx, &ecx, &edx, &dummy);
+ if (error)
+ return (eax >> 8) & 0xff;
+ *status = ebx;
+ *bat = ecx;
+ *life = edx;
+ return APM_SUCCESS;
+}
+
+#if 0
+/* not used anywhere */
+static int apm_get_battery_status(u_short which,
+ u_short *bat, u_short *life, u_short *nbat)
+{
+ u_short status;
+ int error;
+ u32 eax;
+ u32 ebx;
+ u32 ecx;
+ u32 edx;
+ u32 esi;
+
+ if (apm_bios_info.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);
+ }
+
+ error = apm_bios_call(0x530a, (0x8000 | (which)), 0, &eax, &ebx, &ecx, &edx, &esi);
+ if (error)
+ return (eax >> 8) & 0xff;
+ *bat = ecx;
+ *life = edx;
+ *nbat = esi;
+ return APM_SUCCESS;
+}
+#endif
+
+static int apm_engage_power_management(u_short device)
+{
+ int error;
+ u32 eax;
+
+ error = apm_bios_call_simple(0x530f, device, 1, &eax);
+ if (error)
+ return (eax >> 8) & 0xff;
+ return APM_SUCCESS;
+}
+
+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_bios: %s: %s\n", str, error_table[i].msg);
+ else
+ printk(KERN_NOTICE "apm_bios: %s: unknown error code %#2.2x\n", str, err);
+}
+
+/* Called from console driver -- must make sure apm_enabled. */
+int apm_display_blank(void)
+{
+#ifdef CONFIG_APM_DISPLAY_BLANK
+ int error;
+
+ if (!apm_enabled)
+ return 0;
+ error = apm_set_display_power_state(APM_STATE_STANDBY);
+ if (error == APM_SUCCESS)
+ return 1;
+ apm_error("set display standby", error);
+#endif
+ return 0;
+}
+
+/* Called from console driver -- must make sure apm_enabled. */
+int apm_display_unblank(void)
+{
+#ifdef CONFIG_APM_DISPLAY_BLANK
+ int error;
+
+ if (!apm_enabled)
+ return 0;
+ error = apm_set_display_power_state(APM_STATE_READY);
+ if (error == APM_SUCCESS)
+ return 1;
+ apm_error("set display ready", error);
+#endif
+ return 0;
+}
+
+int apm_register_callback(int (*callback)(apm_event_t))
+{
+ callback_list_t * new;
+
+ new = kmalloc(sizeof(callback_list_t), GFP_KERNEL);
+ if (new == NULL)
+ return -ENOMEM;
+ new->callback = callback;
+ new->next = callback_list;
+ callback_list = new;
+ return 0;
+}
+
+void apm_unregister_callback(int (*callback)(apm_event_t))
+{
+ callback_list_t ** ptr;
+ callback_list_t * old;
+
+ ptr = &callback_list;
+ for (ptr = &callback_list; *ptr != NULL; ptr = &(*ptr)->next)
+ if ((*ptr)->callback == callback)
+ break;
+ old = *ptr;
+ *ptr = old->next;
+ kfree_s(old, sizeof(callback_list_t));
+}
+
+static int queue_empty(struct apm_bios_struct * as)
+{
+ return as->event_head == as->event_tail;
+}
+
+static apm_event_t get_queued_event(struct apm_bios_struct * as)
+{
+ as->event_tail = (as->event_tail + 1) % APM_MAX_EVENTS;
+ return as->events[as->event_tail];
+}
+
+static int queue_event(apm_event_t event, struct apm_bios_struct *sender)
+{
+ struct apm_bios_struct * as;
+
+ if (user_list == NULL)
+ return 0;
+ for (as = user_list; as != NULL; as = as->next) {
+ if (as == sender)
+ continue;
+ as->event_head = (as->event_head + 1) % APM_MAX_EVENTS;
+ if (as->event_head == as->event_tail) {
+ static int notified;
+
+ if (notified == 0) {
+ printk( "apm_bios: an event queue overflowed\n" );
+ notified = 1;
+ }
+ as->event_tail = (as->event_tail + 1) % APM_MAX_EVENTS;
+ }
+ as->events[as->event_head] = event;
+ if (!as->suser)
+ continue;
+ switch (event) {
+ case APM_SYS_SUSPEND:
+ case APM_USER_SUSPEND:
+ as->suspends_pending++;
+ suspends_pending++;
+ break;
+
+ case APM_SYS_STANDBY:
+ case APM_USER_STANDBY:
+ as->standbys_pending++;
+ standbys_pending++;
+ break;
+ }
+ }
+ wake_up_interruptible(&process_list);
+ return 1;
+}
+
+static void set_time(void)
+{
+ unsigned long flags;
+
+ if (!got_clock_diff) /* Don't know time zone, can't set clock */
+ return;
+
+ save_flags(flags);
+ cli();
+ CURRENT_TIME = get_cmos_time() + clock_cmos_diff;
+ restore_flags(flags);
+}
+
+static void suspend(void)
+{
+ unsigned long flags;
+ int err;
+
+ /* Estimate time zone so that set_time can
+ update the clock */
+ save_flags(flags);
+ clock_cmos_diff = -get_cmos_time();
+ cli();
+ clock_cmos_diff += CURRENT_TIME;
+ got_clock_diff = 1;
+ restore_flags(flags);
+
+ err = apm_set_power_state(APM_STATE_SUSPEND);
+ if (err)
+ apm_error("suspend", err);
+ set_time();
+}
+
+static void standby(void)
+{
+ int err;
+
+ err = apm_set_power_state(APM_STATE_STANDBY);
+ if (err)
+ apm_error("standby", err);
+}
+
+static apm_event_t get_event(void)
+{
+ int error;
+ apm_event_t event;
+ apm_eventinfo_t info;
+
+ static int notified = 0;
+
+ /* we don't use the eventinfo */
+ error = apm_get_event(&event, &info);
+ if (error == APM_SUCCESS)
+ return event;
+
+ if ((error != APM_NO_EVENTS) && (notified++ == 0))
+ apm_error("get_event", error);
+
+ return 0;
+}
+
+static void send_event(apm_event_t event, apm_event_t undo,
+ struct apm_bios_struct *sender)
+{
+ callback_list_t * call;
+ callback_list_t * fix;
+
+ for (call = callback_list; call != NULL; call = call->next) {
+ if (call->callback(event) && undo) {
+ for (fix = callback_list; fix != call; fix = fix->next)
+ fix->callback(undo);
+ if (apm_bios_info.version > 0x100)
+ apm_set_power_state(APM_STATE_REJECT);
+ return;
+ }
+ }
+
+ queue_event(event, sender);
+}
+
+static void check_events(void)
+{
+ apm_event_t event;
+
+ while ((event = get_event()) != 0) {
+#ifdef APM_DEBUG
+ if (event <= NR_APM_EVENT_NAME)
+ printk(KERN_DEBUG "APM BIOS received %s notify\n",
+ apm_event_name[event - 1]);
+ else
+ printk(KERN_DEBUG "APM BIOS received unknown "
+ "event 0x%02x\n", event);
+#endif
+ switch (event) {
+ case APM_SYS_STANDBY:
+ case APM_USER_STANDBY:
+#ifdef CONFIG_APM_IGNORE_MULTIPLE_SUSPEND
+ if (waiting_for_resume) {
+ return;
+ }
+ waiting_for_resume = 1;
+#endif
+ send_event(event, APM_STANDBY_RESUME, NULL);
+ if (standbys_pending <= 0)
+ standby();
+ break;
+
+ case APM_USER_SUSPEND:
+#ifdef CONFIG_APM_IGNORE_USER_SUSPEND
+ if (apm_bios_info.version > 0x100)
+ apm_set_power_state(APM_STATE_REJECT);
+ break;
+#endif
+ case APM_SYS_SUSPEND:
+#ifdef CONFIG_APM_IGNORE_MULTIPLE_SUSPEND
+ if (waiting_for_resume) {
+ return;
+ }
+ waiting_for_resume = 1;
+#endif
+ send_event(event, APM_NORMAL_RESUME, NULL);
+ if (suspends_pending <= 0)
+ suspend();
+ break;
+
+ case APM_NORMAL_RESUME:
+ case APM_CRITICAL_RESUME:
+ case APM_STANDBY_RESUME:
+#ifdef CONFIG_APM_IGNORE_MULTIPLE_SUSPEND
+ waiting_for_resume = 0;
+#endif
+ set_time();
+ send_event(event, 0, NULL);
+ break;
+
+ case APM_LOW_BATTERY:
+ case APM_POWER_STATUS_CHANGE:
+ case APM_CAPABILITY_CHANGE:
+ send_event(event, 0, NULL);
+ break;
+
+ case APM_UPDATE_TIME:
+ set_time();
+ break;
+
+ case APM_CRITICAL_SUSPEND:
+ suspend();
+ break;
+ }
+ }
+}
+
+static void do_apm_timer(unsigned long unused)
+{
+ int err;
+
+ static int pending_count = 0;
+
+ if (((standbys_pending > 0) || (suspends_pending > 0))
+ && (apm_bios_info.version > 0x100)
+ && (pending_count-- <= 0)) {
+ pending_count = 4;
+
+ err = apm_set_power_state(APM_STATE_BUSY);
+ if (err)
+ apm_error("busy", err);
+ }
+
+ if (!(((standbys_pending > 0) || (suspends_pending > 0))
+ && (apm_bios_info.version == 0x100)))
+ check_events();
+
+ init_timer(&apm_timer);
+ apm_timer.expires = APM_CHECK_TIMEOUT + jiffies;
+ add_timer(&apm_timer);
+}
+
+/* Called from sys_idle, must make sure apm_enabled. */
+int apm_do_idle(void)
+{
+#ifdef CONFIG_APM_CPU_IDLE
+ int error;
+ u32 dummy;
+
+ if (!apm_enabled)
+ return 0;
+
+ error = apm_bios_call_simple(0x5305, 0, 0, &dummy);
+ if (error)
+ return 0;
+
+ clock_slowed = (apm_bios_info.flags & APM_IDLE_SLOWS_CLOCK) != 0;
+ return 1;
+#else
+ return 0;
+#endif
+}
+
+/* Called from sys_idle, must make sure apm_enabled. */
+void apm_do_busy(void)
+{
+#ifdef CONFIG_APM_CPU_IDLE
+ u32 dummy;
+
+ if (apm_enabled
+#ifndef ALWAYS_CALL_BUSY
+ && clock_slowed
+#endif
+ ) {
+ (void) apm_bios_call_simple(0x5306, 0, 0, &dummy);
+ clock_slowed = 0;
+ }
+#endif
+}
+
+static int check_apm_bios_struct(struct apm_bios_struct *as, const char *func)
+{
+ if ((as == NULL) || (as->magic != APM_BIOS_MAGIC)) {
+ printk(KERN_ERR "apm_bios: %s passed bad filp", func);
+ return 1;
+ }
+ return 0;
+}
+
+static ssize_t do_read(struct file *fp, char *buf, size_t count, loff_t *ppos)
+{
+ struct apm_bios_struct * as;
+ int i;
+ apm_event_t event;
+ struct wait_queue wait = { current, NULL };
+
+ as = fp->private_data;
+ if (check_apm_bios_struct(as, "read"))
+ return -EIO;
+ if (count < sizeof(apm_event_t))
+ return -EINVAL;
+ if (queue_empty(as)) {
+ if (fp->f_flags & O_NONBLOCK)
+ return -EAGAIN;
+ add_wait_queue(&process_list, &wait);
+repeat:
+ current->state = TASK_INTERRUPTIBLE;
+ if (queue_empty(as) && !signal_pending(current)) {
+ schedule();
+ goto repeat;
+ }
+ current->state = TASK_RUNNING;
+ remove_wait_queue(&process_list, &wait);
+ }
+ i = count;
+ while ((i >= sizeof(event)) && !queue_empty(as)) {
+ event = get_queued_event(as);
+ copy_to_user(buf, &event, sizeof(event));
+ switch (event) {
+ case APM_SYS_SUSPEND:
+ case APM_USER_SUSPEND:
+ as->suspends_read++;
+ break;
+
+ case APM_SYS_STANDBY:
+ case APM_USER_STANDBY:
+ as->standbys_read++;
+ break;
+ }
+ buf += sizeof(event);
+ i -= sizeof(event);
+ }
+ if (i < count)
+ return count - i;
+ if (signal_pending(current))
+ return -ERESTARTSYS;
+ return 0;
+}
+
+static unsigned int do_poll(struct file *fp, poll_table * wait)
+{
+ struct apm_bios_struct * as;
+
+ as = fp->private_data;
+ if (check_apm_bios_struct(as, "select"))
+ return 0;
+ poll_wait(fp, &process_list, wait);
+ if (!queue_empty(as))
+ return POLLIN | POLLRDNORM;
+ return 0;
+}
+
+static int do_ioctl(struct inode * inode, struct file *filp,
+ u_int cmd, u_long arg)
+{
+ struct apm_bios_struct * as;
+
+ as = filp->private_data;
+ if (check_apm_bios_struct(as, "ioctl"))
+ return -EIO;
+ if (!as->suser)
+ return -EPERM;
+ switch (cmd) {
+ case APM_IOC_STANDBY:
+ if (as->standbys_read > 0) {
+ as->standbys_read--;
+ as->standbys_pending--;
+ standbys_pending--;
+ }
+ else
+ send_event(APM_USER_STANDBY, APM_STANDBY_RESUME, as);
+ if (standbys_pending <= 0)
+ standby();
+ break;
+ case APM_IOC_SUSPEND:
+ if (as->suspends_read > 0) {
+ as->suspends_read--;
+ as->suspends_pending--;
+ suspends_pending--;
+ }
+ else
+ send_event(APM_USER_SUSPEND, APM_NORMAL_RESUME, as);
+ if (suspends_pending <= 0)
+ suspend();
+ break;
+ default:
+ return -EINVAL;
+ }
+ return 0;
+}
+
+static int do_release(struct inode * inode, struct file * filp)
+{
+ struct apm_bios_struct * as;
+
+ as = filp->private_data;
+ filp->private_data = NULL;
+ if (check_apm_bios_struct(as, "release"))
+ return 0;
+ if (as->standbys_pending > 0) {
+ standbys_pending -= as->standbys_pending;
+ if (standbys_pending <= 0)
+ standby();
+ }
+ if (as->suspends_pending > 0) {
+ suspends_pending -= as->suspends_pending;
+ if (suspends_pending <= 0)
+ suspend();
+ }
+ if (user_list == as)
+ user_list = as->next;
+ else {
+ struct apm_bios_struct * as1;
+
+ for (as1 = user_list;
+ (as1 != NULL) && (as1->next != as);
+ as1 = as1->next)
+ ;
+ if (as1 == NULL)
+ printk(KERN_ERR "apm_bios: filp not in user list");
+ else
+ as1->next = as->next;
+ }
+ kfree_s(as, sizeof(*as));
+ return 0;
+}
+
+static int do_open(struct inode * inode, struct file * filp)
+{
+ struct apm_bios_struct * as;
+
+ as = (struct apm_bios_struct *)kmalloc(sizeof(*as), GFP_KERNEL);
+ if (as == NULL) {
+ printk(KERN_ERR "apm_bios: cannot allocate struct of size %d bytes",
+ sizeof(*as));
+ return -ENOMEM;
+ }
+ as->magic = APM_BIOS_MAGIC;
+ as->event_tail = as->event_head = 0;
+ as->suspends_pending = as->standbys_pending = 0;
+ as->suspends_read = as->standbys_read = 0;
+ /*
+ * XXX - this is a tiny bit broken, when we consider BSD
+ * process accounting. If the device is opened by root, we
+ * instantly flag that we used superuser privs. Who knows,
+ * we might close the device immediately without doing a
+ * privileged operation -- cevans
+ */
+ as->suser = capable(CAP_SYS_ADMIN);
+ as->next = user_list;
+ user_list = as;
+ filp->private_data = as;
+ return 0;
+}
+
+#ifdef CONFIG_PROC_FS
+int apm_get_info(char *buf, char **start, off_t fpos, int length, int dummy)
+{
+ char * p;
+ unsigned short bx;
+ unsigned short cx;
+ unsigned short dx;
+ unsigned short error;
+ unsigned short ac_line_status = 0xff;
+ unsigned short battery_status = 0xff;
+ unsigned short battery_flag = 0xff;
+ int percentage = -1;
+ int time_units = -1;
+ char *units = "?";
+
+ if (!apm_enabled)
+ return 0;
+ p = buf;
+
+ if (!(error = apm_get_power_status(&bx, &cx, &dx))) {
+ ac_line_status = (bx >> 8) & 0xff;
+ battery_status = bx & 0xff;
+ if ((cx & 0xff) != 0xff)
+ percentage = cx & 0xff;
+
+ if (apm_bios_info.version > 0x100) {
+ battery_flag = (cx >> 8) & 0xff;
+ if (dx != 0xffff) {
+ if ((dx & 0x8000) == 0x8000) {
+ units = "min";
+ time_units = dx & 0x7ffe;
+ } else {
+ units = "sec";
+ time_units = dx & 0x7fff;
+ }
+ }
+ }
+ }
+ /* Arguments, with symbols from linux/apm_bios.h. Information is
+ from the Get Power Status (0x0a) call unless otherwise noted.
+
+ 0) Linux driver version (this will change if format changes)
+ 1) APM BIOS Version. Usually 1.0 or 1.1.
+ 2) APM flags from APM Installation Check (0x00):
+ bit 0: APM_16_BIT_SUPPORT
+ bit 1: APM_32_BIT_SUPPORT
+ bit 2: APM_IDLE_SLOWS_CLOCK
+ bit 3: APM_BIOS_DISABLED
+ bit 4: APM_BIOS_DISENGAGED
+ 3) AC line status
+ 0x00: Off-line
+ 0x01: On-line
+ 0x02: On backup power (APM BIOS 1.1 only)
+ 0xff: Unknown
+ 4) Battery status
+ 0x00: High
+ 0x01: Low
+ 0x02: Critical
+ 0x03: Charging
+ 0xff: Unknown
+ 5) Battery flag
+ bit 0: High
+ bit 1: Low
+ bit 2: Critical
+ bit 3: Charging
+ bit 7: No system battery
+ 0xff: Unknown
+ 6) Remaining battery life (percentage of charge):
+ 0-100: valid
+ -1: Unknown
+ 7) Remaining battery life (time units):
+ Number of remaining minutes or seconds
+ -1: Unknown
+ 8) min = minutes; sec = seconds */
+
+ p += sprintf(p, "%s %d.%d 0x%02x 0x%02x 0x%02x 0x%02x %d%% %d %s\n",
+ driver_version,
+ (apm_bios_info.version >> 8) & 0xff,
+ apm_bios_info.version & 0xff,
+ apm_bios_info.flags,
+ ac_line_status,
+ battery_status,
+ battery_flag,
+ percentage,
+ time_units,
+ units);
+
+ return p - buf;
+}
+#endif
+
+void __init apm_bios_init(void)
+{
+ unsigned short bx;
+ unsigned short cx;
+ unsigned short dx;
+ unsigned short error;
+ char * power_stat;
+ char * bat_stat;
+ static struct proc_dir_entry *ent;
+
+#ifdef __SMP__
+ if (smp_num_cpus > 1) {
+ printk(KERN_NOTICE "APM disabled: APM is not SMP safe.\n");
+ return;
+ }
+#endif
+ if (apm_bios_info.version == 0) {
+ printk(KERN_INFO "APM BIOS not found.\n");
+ return;
+ }
+ printk(KERN_INFO "APM BIOS version %c.%c Flags 0x%02x (Driver version %s)\n",
+ ((apm_bios_info.version >> 8) & 0xff) + '0',
+ (apm_bios_info.version & 0xff) + '0',
+ apm_bios_info.flags,
+ driver_version);
+ if ((apm_bios_info.flags & APM_32_BIT_SUPPORT) == 0) {
+ printk(KERN_INFO " No 32 bit BIOS support\n");
+ return;
+ }
+
+ /*
+ * Fix for the Compaq Contura 3/25c which reports BIOS version 0.1
+ * but is reportedly a 1.0 BIOS.
+ */
+ if (apm_bios_info.version == 0x001)
+ apm_bios_info.version = 0x100;
+
+ /* BIOS < 1.2 doesn't set cseg_16_len */
+ if (apm_bios_info.version < 0x102)
+ apm_bios_info.cseg_16_len = 0xFFFF; /* 64k */
+
+ printk(KERN_INFO " Entry %x:%lx cseg16 %x dseg %x",
+ apm_bios_info.cseg, apm_bios_info.offset,
+ apm_bios_info.cseg_16, apm_bios_info.dseg);
+ if (apm_bios_info.version > 0x100)
+ printk(" cseg len %x, cseg16 len %x, dseg len %x",
+ apm_bios_info.cseg_len, apm_bios_info.cseg_16_len,
+ apm_bios_info.dseg_len);
+ printk("\n");
+
+ /*
+ * Set up a segment that references the real mode segment 0x40
+ * that extends up to the end of page zero (that we have reserved).
+ * This is for buggy BIOS's that refer to (real mode) segment 0x40
+ * even though they are called in protected mode.
+ */
+ set_base(gdt[APM_40 >> 3],
+ __va((unsigned long)0x40 << 4));
+ set_limit(gdt[APM_40 >> 3], 4096 - (0x40 << 4));
+
+ apm_bios_entry.offset = apm_bios_info.offset;
+ apm_bios_entry.segment = APM_CS;
+ set_base(gdt[APM_CS >> 3],
+ __va((unsigned long)apm_bios_info.cseg << 4));
+ set_base(gdt[APM_CS_16 >> 3],
+ __va((unsigned long)apm_bios_info.cseg_16 << 4));
+ set_base(gdt[APM_DS >> 3],
+ __va((unsigned long)apm_bios_info.dseg << 4));
+ if (apm_bios_info.version == 0x100) {
+ set_limit(gdt[APM_CS >> 3], 64 * 1024);
+ set_limit(gdt[APM_CS_16 >> 3], 64 * 1024);
+ set_limit(gdt[APM_DS >> 3], 64 * 1024);
+ } else {
+#ifdef APM_RELAX_SEGMENTS
+ /* For ASUS motherboard, Award BIOS rev 110 (and others?) */
+ set_limit(gdt[APM_CS >> 3], 64 * 1024);
+ /* For some unknown machine. */
+ set_limit(gdt[APM_CS_16 >> 3], 64 * 1024);
+ /* For the DEC Hinote Ultra CT475 (and others?) */
+ set_limit(gdt[APM_DS >> 3], 64 * 1024);
+#else
+ set_limit(gdt[APM_CS >> 3], apm_bios_info.cseg_len);
+ set_limit(gdt[APM_CS_16 >> 3], apm_bios_info.cseg_16_len);
+ set_limit(gdt[APM_DS >> 3], apm_bios_info.dseg_len);
+#endif
+ /* The APM 1.2 docs state that the apm_driver_version
+ * call can fail if we try to connect as 1.2 to a 1.1 bios.
+ */
+ apm_bios_info.version = 0x0102;
+ error = apm_driver_version(&apm_bios_info.version);
+ if (error != APM_SUCCESS) { /* Fall back to an APM 1.1 connection. */
+ apm_bios_info.version = 0x0101;
+ error = apm_driver_version(&apm_bios_info.version);
+ }
+ if (error != APM_SUCCESS) /* Fall back to an APM 1.0 connection. */
+ apm_bios_info.version = 0x100;
+ else {
+ apm_engage_power_management(0x0001);
+ printk( " Connection version %d.%d\n",
+ (apm_bios_info.version >> 8) & 0xff,
+ apm_bios_info.version & 0xff );
+ }
+ }
+
+ error = apm_get_power_status(&bx, &cx, &dx);
+ if (error)
+ printk(KERN_INFO " Power status not available\n");
+ else {
+ switch ((bx >> 8) & 0xff) {
+ case 0: power_stat = "off line"; break;
+ case 1: power_stat = "on line"; break;
+ case 2: power_stat = "on backup power"; break;
+ default: power_stat = "unknown"; break;
+ }
+ switch (bx & 0xff) {
+ case 0: bat_stat = "high"; break;
+ case 1: bat_stat = "low"; break;
+ case 2: bat_stat = "critical"; break;
+ case 3: bat_stat = "charging"; break;
+ default: bat_stat = "unknown"; break;
+ }
+ printk(KERN_INFO " AC %s, battery status %s, battery life ",
+ power_stat, bat_stat);
+ if ((cx & 0xff) == 0xff)
+ printk("unknown\n");
+ else
+ printk("%d%%\n", cx & 0xff);
+ if (apm_bios_info.version > 0x100) {
+ printk(" battery flag 0x%02x, battery life ",
+ (cx >> 8) & 0xff);
+ if (dx == 0xffff)
+ printk("unknown\n");
+ else {
+ if ((dx & 0x8000))
+ printk("%d minutes\n", dx & 0x7ffe );
+ else
+ printk("%d seconds\n", dx & 0x7fff );
+ }
+ }
+ }
+
+#ifdef CONFIG_APM_DO_ENABLE
+ /*
+ * This call causes my NEC UltraLite Versa 33/C to hang if it is
+ * booted with PM disabled but not in the docking station.
+ * Unfortunate ...
+ */
+ error = apm_enable_power_management();
+ if (error)
+ apm_error("enable power management", error);
+ if (error == APM_DISABLED)
+ return;
+#endif
+
+ init_timer(&apm_timer);
+ apm_timer.function = do_apm_timer;
+ apm_timer.expires = APM_CHECK_TIMEOUT + jiffies;
+ add_timer(&apm_timer);
+
+#ifdef CONFIG_PROC_FS
+ ent = create_proc_entry("apm", 0, 0);
+ ent->get_info = apm_get_info;
+#endif
+
+ misc_register(&apm_device);
+
+ apm_enabled = 1;
+}
FUNET's LINUX-ADM group, linux-adm@nic.funet.fi
TCL-scripts by Sam Shen, slshen@lbl.gov