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)
238 extern int (*console_blank_hook)(int);
239 #endif
240
241 /*
242 * The apm_bios device is one of the misc char devices.
243 * This is its minor number.
244 */
245 #define APM_MINOR_DEV 134
246
247 /*
248 * Various options can be changed at boot time as follows:
249 * (We allow underscores for compatibility with the modules code)
250 * apm=on/off enable/disable APM
251 * [no-]allow[-_]ints allow interrupts during BIOS calls
252 * [no-]broken[-_]psr BIOS has a broken GetPowerStatus call
253 * [no-]realmode[-_]power[-_]off switch to real mode before
254 * powering off
255 * [no-]debug log some debugging messages
256 * [no-]power[-_]off power off on shutdown
257 * [no-]smp Use apm even on an SMP box
258 * bounce[-_]interval=<n> number of ticks to ignore suspend
259 * bounces
260 * idle[-_]threshold=<n> System idle percentage above which to
261 * make APM BIOS idle calls. Set it to
262 * 100 to disable.
263 * idle[-_]period=<n> Period (in 1/100s of a second) over
264 * which the idle percentage is
265 * calculated.
266 */
267
268 /* KNOWN PROBLEM MACHINES:
269 *
270 * U: TI 4000M TravelMate: BIOS is *NOT* APM compliant
271 * [Confirmed by TI representative]
272 * ?: ACER 486DX4/75: uses dseg 0040, in violation of APM specification
273 * [Confirmed by BIOS disassembly]
274 * [This may work now ...]
275 * P: Toshiba 1950S: battery life information only gets updated after resume
276 * P: Midwest Micro Soundbook Elite DX2/66 monochrome: screen blanking
277 * broken in BIOS [Reported by Garst R. Reese <reese@isn.net>]
278 * ?: AcerNote-950: oops on reading /proc/apm - workaround is a WIP
279 * Neale Banks <neale@lowendale.com.au> December 2000
280 *
281 * Legend: U = unusable with APM patches
282 * P = partially usable with APM patches
283 */
284
285 /*
286 * Define as 1 to make the driver always call the APM BIOS busy
287 * routine even if the clock was not reported as slowed by the
288 * idle routine. Otherwise, define as 0.
289 */
290 #define ALWAYS_CALL_BUSY 1
291
292 /*
293 * Define to make the APM BIOS calls zero all data segment registers (so
294 * that an incorrect BIOS implementation will cause a kernel panic if it
295 * tries to write to arbitrary memory).
296 */
297 #define APM_ZERO_SEGS
298
299 #include <asm/apm.h>
300
301 /*
302 * Define to re-initialize the interrupt 0 timer to 100 Hz after a suspend.
303 * This patched by Chad Miller <cmiller@surfsouth.com>, original code by
304 * David Chen <chen@ctpa04.mit.edu>
305 */
306 #undef INIT_TIMER_AFTER_SUSPEND
307
308 #ifdef INIT_TIMER_AFTER_SUSPEND
309 #include <linux/timex.h>
310 #include <asm/io.h>
311 #include <linux/delay.h>
312 #endif
313
314 /*
315 * Need to poll the APM BIOS every second
316 */
317 #define APM_CHECK_TIMEOUT (HZ)
318
319 /*
320 * Ignore suspend events for this amount of time after a resume
321 */
322 #define DEFAULT_BOUNCE_INTERVAL (3 * HZ)
323
324 /*
325 * Maximum number of events stored
326 */
327 #define APM_MAX_EVENTS 20
328
329 /*
330 * The per-file APM data
331 */
332 struct apm_user {
333 int magic;
334 struct apm_user *next;
335 unsigned int suser: 1;
336 unsigned int writer: 1;
337 unsigned int reader: 1;
338 unsigned int suspend_wait: 1;
339 int suspend_result;
340 int suspends_pending;
341 int standbys_pending;
342 int suspends_read;
343 int standbys_read;
344 int event_head;
345 int event_tail;
346 apm_event_t events[APM_MAX_EVENTS];
347 };
348
349 /*
350 * The magic number in apm_user
351 */
352 #define APM_BIOS_MAGIC 0x4101
353
354 /*
355 * idle percentage above which bios idle calls are done
356 */
357 #ifdef CONFIG_APM_CPU_IDLE
358 #define DEFAULT_IDLE_THRESHOLD 95
359 #else
360 #define DEFAULT_IDLE_THRESHOLD 100
361 #endif
362 #define DEFAULT_IDLE_PERIOD (100 / 3)
363
364 static int apm_cpu_idle(struct cpuidle_device *dev,
365 struct cpuidle_driver *drv, int index);
366
367 static struct cpuidle_driver apm_idle_driver = {
368 .name = "apm_idle",
369 .owner = THIS_MODULE,
370 .states = {
371 { /* entry 0 is for polling */ },
372 { /* entry 1 is for APM idle */
373 .name = "APM",
374 .desc = "APM idle",
375 .exit_latency = 250, /* WAG */
376 .target_residency = 500, /* WAG */
377 .enter = &apm_cpu_idle
378 },
379 },
380 .state_count = 2,
381 };
382
383 static struct cpuidle_device apm_cpuidle_device;
384
385 /*
386 * Local variables
387 */
388 __visible struct {
389 unsigned long offset;
390 unsigned short segment;
391 } apm_bios_entry;
392 static int clock_slowed;
393 static int idle_threshold __read_mostly = DEFAULT_IDLE_THRESHOLD;
394 static int idle_period __read_mostly = DEFAULT_IDLE_PERIOD;
395 static int suspends_pending;
396 static int standbys_pending;
397 static int ignore_sys_suspend;
398 static int ignore_normal_resume;
399 static int bounce_interval __read_mostly = DEFAULT_BOUNCE_INTERVAL;
400
401 static bool debug __read_mostly;
402 static bool smp __read_mostly;
403 static int apm_disabled = -1;
404 #ifdef CONFIG_SMP
405 static bool power_off;
406 #else
407 static bool power_off = 1;
408 #endif
409 static bool realmode_power_off;
410 #ifdef CONFIG_APM_ALLOW_INTS
411 static bool allow_ints = 1;
412 #else
413 static bool allow_ints;
414 #endif
415 static bool broken_psr;
416
417 static DECLARE_WAIT_QUEUE_HEAD(apm_waitqueue);
418 static DECLARE_WAIT_QUEUE_HEAD(apm_suspend_waitqueue);
419 static struct apm_user *user_list;
420 static DEFINE_SPINLOCK(user_list_lock);
421 static DEFINE_MUTEX(apm_mutex);
422
423 /*
424 * Set up a segment that references the real mode segment 0x40
425 * that extends up to the end of page zero (that we have reserved).
426 * This is for buggy BIOS's that refer to (real mode) segment 0x40
427 * even though they are called in protected mode.
428 */
429 static struct desc_struct bad_bios_desc = GDT_ENTRY_INIT(0x4092,
430 (unsigned long)__va(0x400UL), PAGE_SIZE - 0x400 - 1);
431
432 static const char driver_version[] = "1.16ac"; /* no spaces */
433
434 static struct task_struct *kapmd_task;
435
436 /*
437 * APM event names taken from the APM 1.2 specification. These are
438 * the message codes that the BIOS uses to tell us about events
439 */
440 static const char * const apm_event_name[] = {
441 "system standby",
442 "system suspend",
443 "normal resume",
444 "critical resume",
445 "low battery",
446 "power status change",
447 "update time",
448 "critical suspend",
449 "user standby",
450 "user suspend",
451 "system standby resume",
452 "capabilities change"
453 };
454 #define NR_APM_EVENT_NAME ARRAY_SIZE(apm_event_name)
455
456 typedef struct lookup_t {
457 int key;
458 char *msg;
459 } lookup_t;
460
461 /*
462 * The BIOS returns a set of standard error codes in AX when the
463 * carry flag is set.
464 */
465
466 static const lookup_t error_table[] = {
467 /* N/A { APM_SUCCESS, "Operation succeeded" }, */
468 { APM_DISABLED, "Power management disabled" },
469 { APM_CONNECTED, "Real mode interface already connected" },
470 { APM_NOT_CONNECTED, "Interface not connected" },
471 { APM_16_CONNECTED, "16 bit interface already connected" },
472 /* N/A { APM_16_UNSUPPORTED, "16 bit interface not supported" }, */
473 { APM_32_CONNECTED, "32 bit interface already connected" },
474 { APM_32_UNSUPPORTED, "32 bit interface not supported" },
475 { APM_BAD_DEVICE, "Unrecognized device ID" },
476 { APM_BAD_PARAM, "Parameter out of range" },
477 { APM_NOT_ENGAGED, "Interface not engaged" },
478 { APM_BAD_FUNCTION, "Function not supported" },
479 { APM_RESUME_DISABLED, "Resume timer disabled" },
480 { APM_BAD_STATE, "Unable to enter requested state" },
481 /* N/A { APM_NO_EVENTS, "No events pending" }, */
482 { APM_NO_ERROR, "BIOS did not set a return code" },
483 { APM_NOT_PRESENT, "No APM present" }
484 };
485 #define ERROR_COUNT ARRAY_SIZE(error_table)
486
487 /**
488 * apm_error - display an APM error
489 * @str: information string
490 * @err: APM BIOS return code
491 *
492 * Write a meaningful log entry to the kernel log in the event of
493 * an APM error. Note that this also handles (negative) kernel errors.
494 */
495
apm_error(char * str,int err)496 static void apm_error(char *str, int err)
497 {
498 int i;
499
500 for (i = 0; i < ERROR_COUNT; i++)
501 if (error_table[i].key == err)
502 break;
503 if (i < ERROR_COUNT)
504 pr_notice("%s: %s\n", str, error_table[i].msg);
505 else if (err < 0)
506 pr_notice("%s: linux error code %i\n", str, err);
507 else
508 pr_notice("%s: unknown error code %#2.2x\n",
509 str, err);
510 }
511
512 /*
513 * These are the actual BIOS calls. Depending on APM_ZERO_SEGS and
514 * apm_info.allow_ints, we are being really paranoid here! Not only
515 * are interrupts disabled, but all the segment registers (except SS)
516 * are saved and zeroed this means that if the BIOS tries to reference
517 * any data without explicitly loading the segment registers, the kernel
518 * will fault immediately rather than have some unforeseen circumstances
519 * for the rest of the kernel. And it will be very obvious! :-) Doing
520 * this depends on CS referring to the same physical memory as DS so that
521 * DS can be zeroed before the call. Unfortunately, we can't do anything
522 * about the stack segment/pointer. Also, we tell the compiler that
523 * everything could change.
524 *
525 * Also, we KNOW that for the non error case of apm_bios_call, there
526 * is no useful data returned in the low order 8 bits of eax.
527 */
528
__apm_irq_save(void)529 static inline unsigned long __apm_irq_save(void)
530 {
531 unsigned long flags;
532 local_save_flags(flags);
533 if (apm_info.allow_ints) {
534 if (irqs_disabled_flags(flags))
535 local_irq_enable();
536 } else
537 local_irq_disable();
538
539 return flags;
540 }
541
542 #define apm_irq_save(flags) \
543 do { flags = __apm_irq_save(); } while (0)
544
apm_irq_restore(unsigned long flags)545 static inline void apm_irq_restore(unsigned long flags)
546 {
547 if (irqs_disabled_flags(flags))
548 local_irq_disable();
549 else if (irqs_disabled())
550 local_irq_enable();
551 }
552
553 #ifdef APM_ZERO_SEGS
554 # define APM_DECL_SEGS \
555 unsigned int saved_fs; unsigned int saved_gs;
556 # define APM_DO_SAVE_SEGS \
557 savesegment(fs, saved_fs); savesegment(gs, saved_gs)
558 # define APM_DO_RESTORE_SEGS \
559 loadsegment(fs, saved_fs); loadsegment(gs, saved_gs)
560 #else
561 # define APM_DECL_SEGS
562 # define APM_DO_SAVE_SEGS
563 # define APM_DO_RESTORE_SEGS
564 #endif
565
566 struct apm_bios_call {
567 u32 func;
568 /* In and out */
569 u32 ebx;
570 u32 ecx;
571 /* Out only */
572 u32 eax;
573 u32 edx;
574 u32 esi;
575
576 /* Error: -ENOMEM, or bits 8-15 of eax */
577 int err;
578 };
579
580 /**
581 * __apm_bios_call - Make an APM BIOS 32bit call
582 * @_call: pointer to struct apm_bios_call.
583 *
584 * Make an APM call using the 32bit protected mode interface. The
585 * caller is responsible for knowing if APM BIOS is configured and
586 * enabled. This call can disable interrupts for a long period of
587 * time on some laptops. The return value is in AH and the carry
588 * flag is loaded into AL. If there is an error, then the error
589 * code is returned in AH (bits 8-15 of eax) and this function
590 * returns non-zero.
591 *
592 * Note: this makes the call on the current CPU.
593 */
__apm_bios_call(void * _call)594 static long __apm_bios_call(void *_call)
595 {
596 APM_DECL_SEGS
597 unsigned long flags;
598 int cpu;
599 struct desc_struct save_desc_40;
600 struct desc_struct *gdt;
601 struct apm_bios_call *call = _call;
602 u64 ibt;
603
604 cpu = get_cpu();
605 BUG_ON(cpu != 0);
606 gdt = get_cpu_gdt_rw(cpu);
607 save_desc_40 = gdt[0x40 / 8];
608 gdt[0x40 / 8] = bad_bios_desc;
609
610 apm_irq_save(flags);
611 firmware_restrict_branch_speculation_start();
612 ibt = ibt_save();
613 APM_DO_SAVE_SEGS;
614 apm_bios_call_asm(call->func, call->ebx, call->ecx,
615 &call->eax, &call->ebx, &call->ecx, &call->edx,
616 &call->esi);
617 APM_DO_RESTORE_SEGS;
618 ibt_restore(ibt);
619 firmware_restrict_branch_speculation_end();
620 apm_irq_restore(flags);
621 gdt[0x40 / 8] = save_desc_40;
622 put_cpu();
623
624 return call->eax & 0xff;
625 }
626
627 /* Run __apm_bios_call or __apm_bios_call_simple on CPU 0 */
on_cpu0(long (* fn)(void *),struct apm_bios_call * call)628 static int on_cpu0(long (*fn)(void *), struct apm_bios_call *call)
629 {
630 int ret;
631
632 /* Don't bother with work_on_cpu in the common case, so we don't
633 * have to worry about OOM or overhead. */
634 if (get_cpu() == 0) {
635 ret = fn(call);
636 put_cpu();
637 } else {
638 put_cpu();
639 ret = work_on_cpu(0, fn, call);
640 }
641
642 /* work_on_cpu can fail with -ENOMEM */
643 if (ret < 0)
644 call->err = ret;
645 else
646 call->err = (call->eax >> 8) & 0xff;
647
648 return ret;
649 }
650
651 /**
652 * apm_bios_call - Make an APM BIOS 32bit call (on CPU 0)
653 * @call: the apm_bios_call registers.
654 *
655 * If there is an error, it is returned in @call.err.
656 */
apm_bios_call(struct apm_bios_call * call)657 static int apm_bios_call(struct apm_bios_call *call)
658 {
659 return on_cpu0(__apm_bios_call, call);
660 }
661
662 /**
663 * __apm_bios_call_simple - Make an APM BIOS 32bit call (on CPU 0)
664 * @_call: pointer to struct apm_bios_call.
665 *
666 * Make a BIOS call that returns one value only, or just status.
667 * If there is an error, then the error code is returned in AH
668 * (bits 8-15 of eax) and this function returns non-zero (it can
669 * also return -ENOMEM). This is used for simpler BIOS operations.
670 * This call may hold interrupts off for a long time on some laptops.
671 *
672 * Note: this makes the call on the current CPU.
673 */
__apm_bios_call_simple(void * _call)674 static long __apm_bios_call_simple(void *_call)
675 {
676 u8 error;
677 APM_DECL_SEGS
678 unsigned long flags;
679 int cpu;
680 struct desc_struct save_desc_40;
681 struct desc_struct *gdt;
682 struct apm_bios_call *call = _call;
683 u64 ibt;
684
685 cpu = get_cpu();
686 BUG_ON(cpu != 0);
687 gdt = get_cpu_gdt_rw(cpu);
688 save_desc_40 = gdt[0x40 / 8];
689 gdt[0x40 / 8] = bad_bios_desc;
690
691 apm_irq_save(flags);
692 firmware_restrict_branch_speculation_start();
693 ibt = ibt_save();
694 APM_DO_SAVE_SEGS;
695 error = apm_bios_call_simple_asm(call->func, call->ebx, call->ecx,
696 &call->eax);
697 APM_DO_RESTORE_SEGS;
698 ibt_restore(ibt);
699 firmware_restrict_branch_speculation_end();
700 apm_irq_restore(flags);
701 gdt[0x40 / 8] = save_desc_40;
702 put_cpu();
703 return error;
704 }
705
706 /**
707 * apm_bios_call_simple - make a simple APM BIOS 32bit call
708 * @func: APM function to invoke
709 * @ebx_in: EBX register value for BIOS call
710 * @ecx_in: ECX register value for BIOS call
711 * @eax: EAX register on return from the BIOS call
712 * @err: bits
713 *
714 * Make a BIOS call that returns one value only, or just status.
715 * If there is an error, then the error code is returned in @err
716 * and this function returns non-zero. This is used for simpler
717 * BIOS operations. This call may hold interrupts off for a long
718 * time on some laptops.
719 */
apm_bios_call_simple(u32 func,u32 ebx_in,u32 ecx_in,u32 * eax,int * err)720 static int apm_bios_call_simple(u32 func, u32 ebx_in, u32 ecx_in, u32 *eax,
721 int *err)
722 {
723 struct apm_bios_call call;
724 int ret;
725
726 call.func = func;
727 call.ebx = ebx_in;
728 call.ecx = ecx_in;
729
730 ret = on_cpu0(__apm_bios_call_simple, &call);
731 *eax = call.eax;
732 *err = call.err;
733 return ret;
734 }
735
736 /**
737 * apm_driver_version - APM driver version
738 * @val: loaded with the APM version on return
739 *
740 * Retrieve the APM version supported by the BIOS. This is only
741 * supported for APM 1.1 or higher. An error indicates APM 1.0 is
742 * probably present.
743 *
744 * On entry val should point to a value indicating the APM driver
745 * version with the high byte being the major and the low byte the
746 * minor number both in BCD
747 *
748 * On return it will hold the BIOS revision supported in the
749 * same format.
750 */
751
apm_driver_version(u_short * val)752 static int apm_driver_version(u_short *val)
753 {
754 u32 eax;
755 int err;
756
757 if (apm_bios_call_simple(APM_FUNC_VERSION, 0, *val, &eax, &err))
758 return err;
759 *val = eax;
760 return APM_SUCCESS;
761 }
762
763 /**
764 * apm_get_event - get an APM event from the BIOS
765 * @event: pointer to the event
766 * @info: point to the event information
767 *
768 * The APM BIOS provides a polled information for event
769 * reporting. The BIOS expects to be polled at least every second
770 * when events are pending. When a message is found the caller should
771 * poll until no more messages are present. However, this causes
772 * problems on some laptops where a suspend event notification is
773 * not cleared until it is acknowledged.
774 *
775 * Additional information is returned in the info pointer, providing
776 * that APM 1.2 is in use. If no messages are pending the value 0x80
777 * is returned (No power management events pending).
778 */
apm_get_event(apm_event_t * event,apm_eventinfo_t * info)779 static int apm_get_event(apm_event_t *event, apm_eventinfo_t *info)
780 {
781 struct apm_bios_call call;
782
783 call.func = APM_FUNC_GET_EVENT;
784 call.ebx = call.ecx = 0;
785
786 if (apm_bios_call(&call))
787 return call.err;
788
789 *event = call.ebx;
790 if (apm_info.connection_version < 0x0102)
791 *info = ~0; /* indicate info not valid */
792 else
793 *info = call.ecx;
794 return APM_SUCCESS;
795 }
796
797 /**
798 * set_power_state - set the power management state
799 * @what: which items to transition
800 * @state: state to transition to
801 *
802 * Request an APM change of state for one or more system devices. The
803 * processor state must be transitioned last of all. what holds the
804 * class of device in the upper byte and the device number (0xFF for
805 * all) for the object to be transitioned.
806 *
807 * The state holds the state to transition to, which may in fact
808 * be an acceptance of a BIOS requested state change.
809 */
810
set_power_state(u_short what,u_short state)811 static int set_power_state(u_short what, u_short state)
812 {
813 u32 eax;
814 int err;
815
816 if (apm_bios_call_simple(APM_FUNC_SET_STATE, what, state, &eax, &err))
817 return err;
818 return APM_SUCCESS;
819 }
820
821 /**
822 * set_system_power_state - set system wide power state
823 * @state: which state to enter
824 *
825 * Transition the entire system into a new APM power state.
826 */
827
set_system_power_state(u_short state)828 static int set_system_power_state(u_short state)
829 {
830 return set_power_state(APM_DEVICE_ALL, state);
831 }
832
833 /**
834 * apm_do_idle - perform power saving
835 *
836 * This function notifies the BIOS that the processor is (in the view
837 * of the OS) idle. It returns -1 in the event that the BIOS refuses
838 * to handle the idle request. On a success the function returns 1
839 * if the BIOS did clock slowing or 0 otherwise.
840 */
841
apm_do_idle(void)842 static int apm_do_idle(void)
843 {
844 u32 eax;
845 u8 ret = 0;
846 int idled = 0;
847 int err = 0;
848
849 if (!need_resched()) {
850 idled = 1;
851 ret = apm_bios_call_simple(APM_FUNC_IDLE, 0, 0, &eax, &err);
852 }
853
854 if (!idled)
855 return 0;
856
857 if (ret) {
858 static unsigned long t;
859
860 /* This always fails on some SMP boards running UP kernels.
861 * Only report the failure the first 5 times.
862 */
863 if (++t < 5) {
864 printk(KERN_DEBUG "apm_do_idle failed (%d)\n", err);
865 t = jiffies;
866 }
867 return -1;
868 }
869 clock_slowed = (apm_info.bios.flags & APM_IDLE_SLOWS_CLOCK) != 0;
870 return clock_slowed;
871 }
872
873 /**
874 * apm_do_busy - inform the BIOS the CPU is busy
875 *
876 * Request that the BIOS brings the CPU back to full performance.
877 */
878
apm_do_busy(void)879 static void apm_do_busy(void)
880 {
881 u32 dummy;
882 int err;
883
884 if (clock_slowed || ALWAYS_CALL_BUSY) {
885 (void)apm_bios_call_simple(APM_FUNC_BUSY, 0, 0, &dummy, &err);
886 clock_slowed = 0;
887 }
888 }
889
890 /*
891 * If no process has really been interested in
892 * the CPU for some time, we want to call BIOS
893 * power management - we probably want
894 * to conserve power.
895 */
896 #define IDLE_CALC_LIMIT (HZ * 100)
897 #define IDLE_LEAKY_MAX 16
898
899 /**
900 * apm_cpu_idle - cpu idling for APM capable Linux
901 *
902 * This is the idling function the kernel executes when APM is available. It
903 * tries to do BIOS powermanagement based on the average system idle time.
904 * Furthermore it calls the system default idle routine.
905 */
906
apm_cpu_idle(struct cpuidle_device * dev,struct cpuidle_driver * drv,int index)907 static int apm_cpu_idle(struct cpuidle_device *dev,
908 struct cpuidle_driver *drv, int index)
909 {
910 static int use_apm_idle; /* = 0 */
911 static unsigned int last_jiffies; /* = 0 */
912 static u64 last_stime; /* = 0 */
913 u64 stime, utime;
914
915 int apm_idle_done = 0;
916 unsigned int jiffies_since_last_check = jiffies - last_jiffies;
917 unsigned int bucket;
918
919 recalc:
920 task_cputime(current, &utime, &stime);
921 if (jiffies_since_last_check > IDLE_CALC_LIMIT) {
922 use_apm_idle = 0;
923 } else if (jiffies_since_last_check > idle_period) {
924 unsigned int idle_percentage;
925
926 idle_percentage = nsecs_to_jiffies(stime - last_stime);
927 idle_percentage *= 100;
928 idle_percentage /= jiffies_since_last_check;
929 use_apm_idle = (idle_percentage > idle_threshold);
930 if (apm_info.forbid_idle)
931 use_apm_idle = 0;
932 }
933
934 last_jiffies = jiffies;
935 last_stime = stime;
936
937 bucket = IDLE_LEAKY_MAX;
938
939 while (!need_resched()) {
940 if (use_apm_idle) {
941 unsigned int t;
942
943 t = jiffies;
944 switch (apm_do_idle()) {
945 case 0:
946 apm_idle_done = 1;
947 if (t != jiffies) {
948 if (bucket) {
949 bucket = IDLE_LEAKY_MAX;
950 continue;
951 }
952 } else if (bucket) {
953 bucket--;
954 continue;
955 }
956 break;
957 case 1:
958 apm_idle_done = 1;
959 break;
960 default: /* BIOS refused */
961 break;
962 }
963 }
964 default_idle();
965 local_irq_disable();
966 jiffies_since_last_check = jiffies - last_jiffies;
967 if (jiffies_since_last_check > idle_period)
968 goto recalc;
969 }
970
971 if (apm_idle_done)
972 apm_do_busy();
973
974 return index;
975 }
976
977 /**
978 * apm_power_off - ask the BIOS to power off
979 *
980 * Handle the power off sequence. This is the one piece of code we
981 * will execute even on SMP machines. In order to deal with BIOS
982 * bugs we support real mode APM BIOS power off calls. We also make
983 * the SMP call on CPU0 as some systems will only honour this call
984 * on their first cpu.
985 */
986
apm_power_off(void)987 static void apm_power_off(void)
988 {
989 /* Some bioses don't like being called from CPU != 0 */
990 if (apm_info.realmode_power_off) {
991 set_cpus_allowed_ptr(current, cpumask_of(0));
992 machine_real_restart(MRR_APM);
993 } else {
994 (void)set_system_power_state(APM_STATE_OFF);
995 }
996 }
997
998 #ifdef CONFIG_APM_DO_ENABLE
999
1000 /**
1001 * apm_enable_power_management - enable BIOS APM power management
1002 * @enable: enable yes/no
1003 *
1004 * Enable or disable the APM BIOS power services.
1005 */
1006
apm_enable_power_management(int enable)1007 static int apm_enable_power_management(int enable)
1008 {
1009 u32 eax;
1010 int err;
1011
1012 if ((enable == 0) && (apm_info.bios.flags & APM_BIOS_DISENGAGED))
1013 return APM_NOT_ENGAGED;
1014 if (apm_bios_call_simple(APM_FUNC_ENABLE_PM, APM_DEVICE_BALL,
1015 enable, &eax, &err))
1016 return err;
1017 if (enable)
1018 apm_info.bios.flags &= ~APM_BIOS_DISABLED;
1019 else
1020 apm_info.bios.flags |= APM_BIOS_DISABLED;
1021 return APM_SUCCESS;
1022 }
1023 #endif
1024
1025 /**
1026 * apm_get_power_status - get current power state
1027 * @status: returned status
1028 * @bat: battery info
1029 * @life: estimated life
1030 *
1031 * Obtain the current power status from the APM BIOS. We return a
1032 * status which gives the rough battery status, and current power
1033 * source. The bat value returned give an estimate as a percentage
1034 * of life and a status value for the battery. The estimated life
1035 * if reported is a lifetime in seconds/minutes at current power
1036 * consumption.
1037 */
1038
apm_get_power_status(u_short * status,u_short * bat,u_short * life)1039 static int apm_get_power_status(u_short *status, u_short *bat, u_short *life)
1040 {
1041 struct apm_bios_call call;
1042
1043 call.func = APM_FUNC_GET_STATUS;
1044 call.ebx = APM_DEVICE_ALL;
1045 call.ecx = 0;
1046
1047 if (apm_info.get_power_status_broken)
1048 return APM_32_UNSUPPORTED;
1049 if (apm_bios_call(&call)) {
1050 if (!call.err)
1051 return APM_NO_ERROR;
1052 return call.err;
1053 }
1054 *status = call.ebx;
1055 *bat = call.ecx;
1056 if (apm_info.get_power_status_swabinminutes) {
1057 *life = swab16((u16)call.edx);
1058 *life |= 0x8000;
1059 } else
1060 *life = call.edx;
1061 return APM_SUCCESS;
1062 }
1063
1064 #if 0
1065 static int apm_get_battery_status(u_short which, u_short *status,
1066 u_short *bat, u_short *life, u_short *nbat)
1067 {
1068 u32 eax;
1069 u32 ebx;
1070 u32 ecx;
1071 u32 edx;
1072 u32 esi;
1073
1074 if (apm_info.connection_version < 0x0102) {
1075 /* pretend we only have one battery. */
1076 if (which != 1)
1077 return APM_BAD_DEVICE;
1078 *nbat = 1;
1079 return apm_get_power_status(status, bat, life);
1080 }
1081
1082 if (apm_bios_call(APM_FUNC_GET_STATUS, (0x8000 | (which)), 0, &eax,
1083 &ebx, &ecx, &edx, &esi))
1084 return (eax >> 8) & 0xff;
1085 *status = ebx;
1086 *bat = ecx;
1087 *life = edx;
1088 *nbat = esi;
1089 return APM_SUCCESS;
1090 }
1091 #endif
1092
1093 /**
1094 * apm_engage_power_management - enable PM on a device
1095 * @device: identity of device
1096 * @enable: on/off
1097 *
1098 * Activate or deactivate power management on either a specific device
1099 * or the entire system (%APM_DEVICE_ALL).
1100 */
1101
apm_engage_power_management(u_short device,int enable)1102 static int apm_engage_power_management(u_short device, int enable)
1103 {
1104 u32 eax;
1105 int err;
1106
1107 if ((enable == 0) && (device == APM_DEVICE_ALL)
1108 && (apm_info.bios.flags & APM_BIOS_DISABLED))
1109 return APM_DISABLED;
1110 if (apm_bios_call_simple(APM_FUNC_ENGAGE_PM, device, enable,
1111 &eax, &err))
1112 return err;
1113 if (device == APM_DEVICE_ALL) {
1114 if (enable)
1115 apm_info.bios.flags &= ~APM_BIOS_DISENGAGED;
1116 else
1117 apm_info.bios.flags |= APM_BIOS_DISENGAGED;
1118 }
1119 return APM_SUCCESS;
1120 }
1121
1122 #if defined(CONFIG_APM_DISPLAY_BLANK) && defined(CONFIG_VT)
1123
1124 /**
1125 * apm_console_blank - blank the display
1126 * @blank: on/off
1127 *
1128 * Attempt to blank the console, firstly by blanking just video device
1129 * zero, and if that fails (some BIOSes don't support it) then it blanks
1130 * all video devices. Typically the BIOS will do laptop backlight and
1131 * monitor powerdown for us.
1132 */
1133
apm_console_blank(int blank)1134 static int apm_console_blank(int blank)
1135 {
1136 int error = APM_NOT_ENGAGED; /* silence gcc */
1137 int i;
1138 u_short state;
1139 static const u_short dev[3] = { 0x100, 0x1FF, 0x101 };
1140
1141 state = blank ? APM_STATE_STANDBY : APM_STATE_READY;
1142
1143 for (i = 0; i < ARRAY_SIZE(dev); i++) {
1144 error = set_power_state(dev[i], state);
1145
1146 if ((error == APM_SUCCESS) || (error == APM_NO_ERROR))
1147 return 1;
1148
1149 if (error == APM_NOT_ENGAGED)
1150 break;
1151 }
1152
1153 if (error == APM_NOT_ENGAGED) {
1154 static int tried;
1155 int eng_error;
1156 if (tried++ == 0) {
1157 eng_error = apm_engage_power_management(APM_DEVICE_ALL, 1);
1158 if (eng_error) {
1159 apm_error("set display", error);
1160 apm_error("engage interface", eng_error);
1161 return 0;
1162 } else
1163 return apm_console_blank(blank);
1164 }
1165 }
1166 apm_error("set display", error);
1167 return 0;
1168 }
1169 #endif
1170
queue_empty(struct apm_user * as)1171 static int queue_empty(struct apm_user *as)
1172 {
1173 return as->event_head == as->event_tail;
1174 }
1175
get_queued_event(struct apm_user * as)1176 static apm_event_t get_queued_event(struct apm_user *as)
1177 {
1178 if (++as->event_tail >= APM_MAX_EVENTS)
1179 as->event_tail = 0;
1180 return as->events[as->event_tail];
1181 }
1182
queue_event(apm_event_t event,struct apm_user * sender)1183 static void queue_event(apm_event_t event, struct apm_user *sender)
1184 {
1185 struct apm_user *as;
1186
1187 spin_lock(&user_list_lock);
1188 if (user_list == NULL)
1189 goto out;
1190 for (as = user_list; as != NULL; as = as->next) {
1191 if ((as == sender) || (!as->reader))
1192 continue;
1193 if (++as->event_head >= APM_MAX_EVENTS)
1194 as->event_head = 0;
1195
1196 if (as->event_head == as->event_tail) {
1197 static int notified;
1198
1199 if (notified++ == 0)
1200 pr_err("an event queue overflowed\n");
1201 if (++as->event_tail >= APM_MAX_EVENTS)
1202 as->event_tail = 0;
1203 }
1204 as->events[as->event_head] = event;
1205 if (!as->suser || !as->writer)
1206 continue;
1207 switch (event) {
1208 case APM_SYS_SUSPEND:
1209 case APM_USER_SUSPEND:
1210 as->suspends_pending++;
1211 suspends_pending++;
1212 break;
1213
1214 case APM_SYS_STANDBY:
1215 case APM_USER_STANDBY:
1216 as->standbys_pending++;
1217 standbys_pending++;
1218 break;
1219 }
1220 }
1221 wake_up_interruptible(&apm_waitqueue);
1222 out:
1223 spin_unlock(&user_list_lock);
1224 }
1225
reinit_timer(void)1226 static void reinit_timer(void)
1227 {
1228 #ifdef INIT_TIMER_AFTER_SUSPEND
1229 unsigned long flags;
1230
1231 raw_spin_lock_irqsave(&i8253_lock, flags);
1232 /* set the clock to HZ */
1233 outb_p(0x34, PIT_MODE); /* binary, mode 2, LSB/MSB, ch 0 */
1234 udelay(10);
1235 outb_p(LATCH & 0xff, PIT_CH0); /* LSB */
1236 udelay(10);
1237 outb_p(LATCH >> 8, PIT_CH0); /* MSB */
1238 udelay(10);
1239 raw_spin_unlock_irqrestore(&i8253_lock, flags);
1240 #endif
1241 }
1242
suspend(int vetoable)1243 static int suspend(int vetoable)
1244 {
1245 int err;
1246 struct apm_user *as;
1247
1248 dpm_suspend_start(PMSG_SUSPEND);
1249 dpm_suspend_end(PMSG_SUSPEND);
1250
1251 local_irq_disable();
1252 syscore_suspend();
1253
1254 local_irq_enable();
1255
1256 save_processor_state();
1257 err = set_system_power_state(APM_STATE_SUSPEND);
1258 ignore_normal_resume = 1;
1259 restore_processor_state();
1260
1261 local_irq_disable();
1262 reinit_timer();
1263
1264 if (err == APM_NO_ERROR)
1265 err = APM_SUCCESS;
1266 if (err != APM_SUCCESS)
1267 apm_error("suspend", err);
1268 err = (err == APM_SUCCESS) ? 0 : -EIO;
1269
1270 syscore_resume();
1271 local_irq_enable();
1272
1273 dpm_resume_start(PMSG_RESUME);
1274 dpm_resume_end(PMSG_RESUME);
1275
1276 queue_event(APM_NORMAL_RESUME, NULL);
1277 spin_lock(&user_list_lock);
1278 for (as = user_list; as != NULL; as = as->next) {
1279 as->suspend_wait = 0;
1280 as->suspend_result = err;
1281 }
1282 spin_unlock(&user_list_lock);
1283 wake_up_interruptible(&apm_suspend_waitqueue);
1284 return err;
1285 }
1286
standby(void)1287 static void standby(void)
1288 {
1289 int err;
1290
1291 dpm_suspend_end(PMSG_SUSPEND);
1292
1293 local_irq_disable();
1294 syscore_suspend();
1295 local_irq_enable();
1296
1297 err = set_system_power_state(APM_STATE_STANDBY);
1298 if ((err != APM_SUCCESS) && (err != APM_NO_ERROR))
1299 apm_error("standby", err);
1300
1301 local_irq_disable();
1302 syscore_resume();
1303 local_irq_enable();
1304
1305 dpm_resume_start(PMSG_RESUME);
1306 }
1307
get_event(void)1308 static apm_event_t get_event(void)
1309 {
1310 int error;
1311 apm_event_t event = APM_NO_EVENTS; /* silence gcc */
1312 apm_eventinfo_t info;
1313
1314 static int notified;
1315
1316 /* we don't use the eventinfo */
1317 error = apm_get_event(&event, &info);
1318 if (error == APM_SUCCESS)
1319 return event;
1320
1321 if ((error != APM_NO_EVENTS) && (notified++ == 0))
1322 apm_error("get_event", error);
1323
1324 return 0;
1325 }
1326
check_events(void)1327 static void check_events(void)
1328 {
1329 apm_event_t event;
1330 static unsigned long last_resume;
1331 static int ignore_bounce;
1332
1333 while ((event = get_event()) != 0) {
1334 if (debug) {
1335 if (event <= NR_APM_EVENT_NAME)
1336 printk(KERN_DEBUG "apm: received %s notify\n",
1337 apm_event_name[event - 1]);
1338 else
1339 printk(KERN_DEBUG "apm: received unknown "
1340 "event 0x%02x\n", event);
1341 }
1342 if (ignore_bounce
1343 && (time_after(jiffies, last_resume + bounce_interval)))
1344 ignore_bounce = 0;
1345
1346 switch (event) {
1347 case APM_SYS_STANDBY:
1348 case APM_USER_STANDBY:
1349 queue_event(event, NULL);
1350 if (standbys_pending <= 0)
1351 standby();
1352 break;
1353
1354 case APM_USER_SUSPEND:
1355 #ifdef CONFIG_APM_IGNORE_USER_SUSPEND
1356 if (apm_info.connection_version > 0x100)
1357 set_system_power_state(APM_STATE_REJECT);
1358 break;
1359 #endif
1360 case APM_SYS_SUSPEND:
1361 if (ignore_bounce) {
1362 if (apm_info.connection_version > 0x100)
1363 set_system_power_state(APM_STATE_REJECT);
1364 break;
1365 }
1366 /*
1367 * If we are already processing a SUSPEND,
1368 * then further SUSPEND events from the BIOS
1369 * will be ignored. We also return here to
1370 * cope with the fact that the Thinkpads keep
1371 * sending a SUSPEND event until something else
1372 * happens!
1373 */
1374 if (ignore_sys_suspend)
1375 return;
1376 ignore_sys_suspend = 1;
1377 queue_event(event, NULL);
1378 if (suspends_pending <= 0)
1379 (void) suspend(1);
1380 break;
1381
1382 case APM_NORMAL_RESUME:
1383 case APM_CRITICAL_RESUME:
1384 case APM_STANDBY_RESUME:
1385 ignore_sys_suspend = 0;
1386 last_resume = jiffies;
1387 ignore_bounce = 1;
1388 if ((event != APM_NORMAL_RESUME)
1389 || (ignore_normal_resume == 0)) {
1390 dpm_resume_end(PMSG_RESUME);
1391 queue_event(event, NULL);
1392 }
1393 ignore_normal_resume = 0;
1394 break;
1395
1396 case APM_CAPABILITY_CHANGE:
1397 case APM_LOW_BATTERY:
1398 case APM_POWER_STATUS_CHANGE:
1399 queue_event(event, NULL);
1400 /* If needed, notify drivers here */
1401 break;
1402
1403 case APM_UPDATE_TIME:
1404 break;
1405
1406 case APM_CRITICAL_SUSPEND:
1407 /*
1408 * We are not allowed to reject a critical suspend.
1409 */
1410 (void)suspend(0);
1411 break;
1412 }
1413 }
1414 }
1415
apm_event_handler(void)1416 static void apm_event_handler(void)
1417 {
1418 static int pending_count = 4;
1419 int err;
1420
1421 if ((standbys_pending > 0) || (suspends_pending > 0)) {
1422 if ((apm_info.connection_version > 0x100) &&
1423 (pending_count-- <= 0)) {
1424 pending_count = 4;
1425 if (debug)
1426 printk(KERN_DEBUG "apm: setting state busy\n");
1427 err = set_system_power_state(APM_STATE_BUSY);
1428 if (err)
1429 apm_error("busy", err);
1430 }
1431 } else
1432 pending_count = 4;
1433 check_events();
1434 }
1435
1436 /*
1437 * This is the APM thread main loop.
1438 */
1439
apm_mainloop(void)1440 static void apm_mainloop(void)
1441 {
1442 DECLARE_WAITQUEUE(wait, current);
1443
1444 add_wait_queue(&apm_waitqueue, &wait);
1445 set_current_state(TASK_INTERRUPTIBLE);
1446 for (;;) {
1447 schedule_timeout(APM_CHECK_TIMEOUT);
1448 if (kthread_should_stop())
1449 break;
1450 /*
1451 * Ok, check all events, check for idle (and mark us sleeping
1452 * so as not to count towards the load average)..
1453 */
1454 set_current_state(TASK_INTERRUPTIBLE);
1455 apm_event_handler();
1456 }
1457 remove_wait_queue(&apm_waitqueue, &wait);
1458 }
1459
check_apm_user(struct apm_user * as,const char * func)1460 static int check_apm_user(struct apm_user *as, const char *func)
1461 {
1462 if (as == NULL || as->magic != APM_BIOS_MAGIC) {
1463 pr_err("%s passed bad filp\n", func);
1464 return 1;
1465 }
1466 return 0;
1467 }
1468
do_read(struct file * fp,char __user * buf,size_t count,loff_t * ppos)1469 static ssize_t do_read(struct file *fp, char __user *buf, size_t count, loff_t *ppos)
1470 {
1471 struct apm_user *as;
1472 int i;
1473 apm_event_t event;
1474
1475 as = fp->private_data;
1476 if (check_apm_user(as, "read"))
1477 return -EIO;
1478 if ((int)count < sizeof(apm_event_t))
1479 return -EINVAL;
1480 if ((queue_empty(as)) && (fp->f_flags & O_NONBLOCK))
1481 return -EAGAIN;
1482 wait_event_interruptible(apm_waitqueue, !queue_empty(as));
1483 i = count;
1484 while ((i >= sizeof(event)) && !queue_empty(as)) {
1485 event = get_queued_event(as);
1486 if (copy_to_user(buf, &event, sizeof(event))) {
1487 if (i < count)
1488 break;
1489 return -EFAULT;
1490 }
1491 switch (event) {
1492 case APM_SYS_SUSPEND:
1493 case APM_USER_SUSPEND:
1494 as->suspends_read++;
1495 break;
1496
1497 case APM_SYS_STANDBY:
1498 case APM_USER_STANDBY:
1499 as->standbys_read++;
1500 break;
1501 }
1502 buf += sizeof(event);
1503 i -= sizeof(event);
1504 }
1505 if (i < count)
1506 return count - i;
1507 if (signal_pending(current))
1508 return -ERESTARTSYS;
1509 return 0;
1510 }
1511
do_poll(struct file * fp,poll_table * wait)1512 static __poll_t do_poll(struct file *fp, poll_table *wait)
1513 {
1514 struct apm_user *as;
1515
1516 as = fp->private_data;
1517 if (check_apm_user(as, "poll"))
1518 return 0;
1519 poll_wait(fp, &apm_waitqueue, wait);
1520 if (!queue_empty(as))
1521 return EPOLLIN | EPOLLRDNORM;
1522 return 0;
1523 }
1524
do_ioctl(struct file * filp,u_int cmd,u_long arg)1525 static long do_ioctl(struct file *filp, u_int cmd, u_long arg)
1526 {
1527 struct apm_user *as;
1528 int ret;
1529
1530 as = filp->private_data;
1531 if (check_apm_user(as, "ioctl"))
1532 return -EIO;
1533 if (!as->suser || !as->writer)
1534 return -EPERM;
1535 switch (cmd) {
1536 case APM_IOC_STANDBY:
1537 mutex_lock(&apm_mutex);
1538 if (as->standbys_read > 0) {
1539 as->standbys_read--;
1540 as->standbys_pending--;
1541 standbys_pending--;
1542 } else
1543 queue_event(APM_USER_STANDBY, as);
1544 if (standbys_pending <= 0)
1545 standby();
1546 mutex_unlock(&apm_mutex);
1547 break;
1548 case APM_IOC_SUSPEND:
1549 mutex_lock(&apm_mutex);
1550 if (as->suspends_read > 0) {
1551 as->suspends_read--;
1552 as->suspends_pending--;
1553 suspends_pending--;
1554 } else
1555 queue_event(APM_USER_SUSPEND, as);
1556 if (suspends_pending <= 0) {
1557 ret = suspend(1);
1558 mutex_unlock(&apm_mutex);
1559 } else {
1560 as->suspend_wait = 1;
1561 mutex_unlock(&apm_mutex);
1562 wait_event_interruptible(apm_suspend_waitqueue,
1563 as->suspend_wait == 0);
1564 ret = as->suspend_result;
1565 }
1566 return ret;
1567 default:
1568 return -ENOTTY;
1569 }
1570 return 0;
1571 }
1572
do_release(struct inode * inode,struct file * filp)1573 static int do_release(struct inode *inode, struct file *filp)
1574 {
1575 struct apm_user *as;
1576
1577 as = filp->private_data;
1578 if (check_apm_user(as, "release"))
1579 return 0;
1580 filp->private_data = NULL;
1581 if (as->standbys_pending > 0) {
1582 standbys_pending -= as->standbys_pending;
1583 if (standbys_pending <= 0)
1584 standby();
1585 }
1586 if (as->suspends_pending > 0) {
1587 suspends_pending -= as->suspends_pending;
1588 if (suspends_pending <= 0)
1589 (void) suspend(1);
1590 }
1591 spin_lock(&user_list_lock);
1592 if (user_list == as)
1593 user_list = as->next;
1594 else {
1595 struct apm_user *as1;
1596
1597 for (as1 = user_list;
1598 (as1 != NULL) && (as1->next != as);
1599 as1 = as1->next)
1600 ;
1601 if (as1 == NULL)
1602 pr_err("filp not in user list\n");
1603 else
1604 as1->next = as->next;
1605 }
1606 spin_unlock(&user_list_lock);
1607 kfree(as);
1608 return 0;
1609 }
1610
do_open(struct inode * inode,struct file * filp)1611 static int do_open(struct inode *inode, struct file *filp)
1612 {
1613 struct apm_user *as;
1614
1615 as = kmalloc(sizeof(*as), GFP_KERNEL);
1616 if (as == NULL)
1617 return -ENOMEM;
1618
1619 as->magic = APM_BIOS_MAGIC;
1620 as->event_tail = as->event_head = 0;
1621 as->suspends_pending = as->standbys_pending = 0;
1622 as->suspends_read = as->standbys_read = 0;
1623 /*
1624 * XXX - this is a tiny bit broken, when we consider BSD
1625 * process accounting. If the device is opened by root, we
1626 * instantly flag that we used superuser privs. Who knows,
1627 * we might close the device immediately without doing a
1628 * privileged operation -- cevans
1629 */
1630 as->suser = capable(CAP_SYS_ADMIN);
1631 as->writer = (filp->f_mode & FMODE_WRITE) == FMODE_WRITE;
1632 as->reader = (filp->f_mode & FMODE_READ) == FMODE_READ;
1633 spin_lock(&user_list_lock);
1634 as->next = user_list;
1635 user_list = as;
1636 spin_unlock(&user_list_lock);
1637 filp->private_data = as;
1638 return 0;
1639 }
1640
1641 #ifdef CONFIG_PROC_FS
proc_apm_show(struct seq_file * m,void * v)1642 static int proc_apm_show(struct seq_file *m, void *v)
1643 {
1644 unsigned short bx;
1645 unsigned short cx;
1646 unsigned short dx;
1647 int error;
1648 unsigned short ac_line_status = 0xff;
1649 unsigned short battery_status = 0xff;
1650 unsigned short battery_flag = 0xff;
1651 int percentage = -1;
1652 int time_units = -1;
1653 char *units = "?";
1654
1655 if ((num_online_cpus() == 1) &&
1656 !(error = apm_get_power_status(&bx, &cx, &dx))) {
1657 ac_line_status = (bx >> 8) & 0xff;
1658 battery_status = bx & 0xff;
1659 if ((cx & 0xff) != 0xff)
1660 percentage = cx & 0xff;
1661
1662 if (apm_info.connection_version > 0x100) {
1663 battery_flag = (cx >> 8) & 0xff;
1664 if (dx != 0xffff) {
1665 units = (dx & 0x8000) ? "min" : "sec";
1666 time_units = dx & 0x7fff;
1667 }
1668 }
1669 }
1670 /* Arguments, with symbols from linux/apm_bios.h. Information is
1671 from the Get Power Status (0x0a) call unless otherwise noted.
1672
1673 0) Linux driver version (this will change if format changes)
1674 1) APM BIOS Version. Usually 1.0, 1.1 or 1.2.
1675 2) APM flags from APM Installation Check (0x00):
1676 bit 0: APM_16_BIT_SUPPORT
1677 bit 1: APM_32_BIT_SUPPORT
1678 bit 2: APM_IDLE_SLOWS_CLOCK
1679 bit 3: APM_BIOS_DISABLED
1680 bit 4: APM_BIOS_DISENGAGED
1681 3) AC line status
1682 0x00: Off-line
1683 0x01: On-line
1684 0x02: On backup power (BIOS >= 1.1 only)
1685 0xff: Unknown
1686 4) Battery status
1687 0x00: High
1688 0x01: Low
1689 0x02: Critical
1690 0x03: Charging
1691 0x04: Selected battery not present (BIOS >= 1.2 only)
1692 0xff: Unknown
1693 5) Battery flag
1694 bit 0: High
1695 bit 1: Low
1696 bit 2: Critical
1697 bit 3: Charging
1698 bit 7: No system battery
1699 0xff: Unknown
1700 6) Remaining battery life (percentage of charge):
1701 0-100: valid
1702 -1: Unknown
1703 7) Remaining battery life (time units):
1704 Number of remaining minutes or seconds
1705 -1: Unknown
1706 8) min = minutes; sec = seconds */
1707
1708 seq_printf(m, "%s %d.%d 0x%02x 0x%02x 0x%02x 0x%02x %d%% %d %s\n",
1709 driver_version,
1710 (apm_info.bios.version >> 8) & 0xff,
1711 apm_info.bios.version & 0xff,
1712 apm_info.bios.flags,
1713 ac_line_status,
1714 battery_status,
1715 battery_flag,
1716 percentage,
1717 time_units,
1718 units);
1719 return 0;
1720 }
1721 #endif
1722
apm(void * unused)1723 static int apm(void *unused)
1724 {
1725 unsigned short bx;
1726 unsigned short cx;
1727 unsigned short dx;
1728 int error;
1729 char *power_stat;
1730 char *bat_stat;
1731
1732 /* 2002/08/01 - WT
1733 * This is to avoid random crashes at boot time during initialization
1734 * on SMP systems in case of "apm=power-off" mode. Seen on ASUS A7M266D.
1735 * Some bioses don't like being called from CPU != 0.
1736 * Method suggested by Ingo Molnar.
1737 */
1738 set_cpus_allowed_ptr(current, cpumask_of(0));
1739 BUG_ON(smp_processor_id() != 0);
1740
1741 if (apm_info.connection_version == 0) {
1742 apm_info.connection_version = apm_info.bios.version;
1743 if (apm_info.connection_version > 0x100) {
1744 /*
1745 * We only support BIOSs up to version 1.2
1746 */
1747 if (apm_info.connection_version > 0x0102)
1748 apm_info.connection_version = 0x0102;
1749 error = apm_driver_version(&apm_info.connection_version);
1750 if (error != APM_SUCCESS) {
1751 apm_error("driver version", error);
1752 /* Fall back to an APM 1.0 connection. */
1753 apm_info.connection_version = 0x100;
1754 }
1755 }
1756 }
1757
1758 if (debug)
1759 printk(KERN_INFO "apm: Connection version %d.%d\n",
1760 (apm_info.connection_version >> 8) & 0xff,
1761 apm_info.connection_version & 0xff);
1762
1763 #ifdef CONFIG_APM_DO_ENABLE
1764 if (apm_info.bios.flags & APM_BIOS_DISABLED) {
1765 /*
1766 * This call causes my NEC UltraLite Versa 33/C to hang if it
1767 * is booted with PM disabled but not in the docking station.
1768 * Unfortunate ...
1769 */
1770 error = apm_enable_power_management(1);
1771 if (error) {
1772 apm_error("enable power management", error);
1773 return -1;
1774 }
1775 }
1776 #endif
1777
1778 if ((apm_info.bios.flags & APM_BIOS_DISENGAGED)
1779 && (apm_info.connection_version > 0x0100)) {
1780 error = apm_engage_power_management(APM_DEVICE_ALL, 1);
1781 if (error) {
1782 apm_error("engage power management", error);
1783 return -1;
1784 }
1785 }
1786
1787 if (debug && (num_online_cpus() == 1 || smp)) {
1788 error = apm_get_power_status(&bx, &cx, &dx);
1789 if (error)
1790 printk(KERN_INFO "apm: power status not available\n");
1791 else {
1792 switch ((bx >> 8) & 0xff) {
1793 case 0:
1794 power_stat = "off line";
1795 break;
1796 case 1:
1797 power_stat = "on line";
1798 break;
1799 case 2:
1800 power_stat = "on backup power";
1801 break;
1802 default:
1803 power_stat = "unknown";
1804 break;
1805 }
1806 switch (bx & 0xff) {
1807 case 0:
1808 bat_stat = "high";
1809 break;
1810 case 1:
1811 bat_stat = "low";
1812 break;
1813 case 2:
1814 bat_stat = "critical";
1815 break;
1816 case 3:
1817 bat_stat = "charging";
1818 break;
1819 default:
1820 bat_stat = "unknown";
1821 break;
1822 }
1823 printk(KERN_INFO
1824 "apm: AC %s, battery status %s, battery life ",
1825 power_stat, bat_stat);
1826 if ((cx & 0xff) == 0xff)
1827 printk("unknown\n");
1828 else
1829 printk("%d%%\n", cx & 0xff);
1830 if (apm_info.connection_version > 0x100) {
1831 printk(KERN_INFO
1832 "apm: battery flag 0x%02x, battery life ",
1833 (cx >> 8) & 0xff);
1834 if (dx == 0xffff)
1835 printk("unknown\n");
1836 else
1837 printk("%d %s\n", dx & 0x7fff,
1838 (dx & 0x8000) ?
1839 "minutes" : "seconds");
1840 }
1841 }
1842 }
1843
1844 /* Install our power off handler.. */
1845 if (power_off)
1846 pm_power_off = apm_power_off;
1847
1848 if (num_online_cpus() == 1 || smp) {
1849 #if defined(CONFIG_APM_DISPLAY_BLANK) && defined(CONFIG_VT)
1850 console_blank_hook = apm_console_blank;
1851 #endif
1852 apm_mainloop();
1853 #if defined(CONFIG_APM_DISPLAY_BLANK) && defined(CONFIG_VT)
1854 console_blank_hook = NULL;
1855 #endif
1856 }
1857
1858 return 0;
1859 }
1860
1861 #ifndef MODULE
apm_setup(char * str)1862 static int __init apm_setup(char *str)
1863 {
1864 int invert;
1865
1866 while ((str != NULL) && (*str != '\0')) {
1867 if (strncmp(str, "off", 3) == 0)
1868 apm_disabled = 1;
1869 if (strncmp(str, "on", 2) == 0)
1870 apm_disabled = 0;
1871 if ((strncmp(str, "bounce-interval=", 16) == 0) ||
1872 (strncmp(str, "bounce_interval=", 16) == 0))
1873 bounce_interval = simple_strtol(str + 16, NULL, 0);
1874 if ((strncmp(str, "idle-threshold=", 15) == 0) ||
1875 (strncmp(str, "idle_threshold=", 15) == 0))
1876 idle_threshold = simple_strtol(str + 15, NULL, 0);
1877 if ((strncmp(str, "idle-period=", 12) == 0) ||
1878 (strncmp(str, "idle_period=", 12) == 0))
1879 idle_period = simple_strtol(str + 12, NULL, 0);
1880 invert = (strncmp(str, "no-", 3) == 0) ||
1881 (strncmp(str, "no_", 3) == 0);
1882 if (invert)
1883 str += 3;
1884 if (strncmp(str, "debug", 5) == 0)
1885 debug = !invert;
1886 if ((strncmp(str, "power-off", 9) == 0) ||
1887 (strncmp(str, "power_off", 9) == 0))
1888 power_off = !invert;
1889 if (strncmp(str, "smp", 3) == 0) {
1890 smp = !invert;
1891 idle_threshold = 100;
1892 }
1893 if ((strncmp(str, "allow-ints", 10) == 0) ||
1894 (strncmp(str, "allow_ints", 10) == 0))
1895 apm_info.allow_ints = !invert;
1896 if ((strncmp(str, "broken-psr", 10) == 0) ||
1897 (strncmp(str, "broken_psr", 10) == 0))
1898 apm_info.get_power_status_broken = !invert;
1899 if ((strncmp(str, "realmode-power-off", 18) == 0) ||
1900 (strncmp(str, "realmode_power_off", 18) == 0))
1901 apm_info.realmode_power_off = !invert;
1902 str = strchr(str, ',');
1903 if (str != NULL)
1904 str += strspn(str, ", \t");
1905 }
1906 return 1;
1907 }
1908
1909 __setup("apm=", apm_setup);
1910 #endif
1911
1912 static const struct file_operations apm_bios_fops = {
1913 .owner = THIS_MODULE,
1914 .read = do_read,
1915 .poll = do_poll,
1916 .unlocked_ioctl = do_ioctl,
1917 .open = do_open,
1918 .release = do_release,
1919 .llseek = noop_llseek,
1920 };
1921
1922 static struct miscdevice apm_device = {
1923 APM_MINOR_DEV,
1924 "apm_bios",
1925 &apm_bios_fops
1926 };
1927
1928
1929 /* Simple "print if true" callback */
print_if_true(const struct dmi_system_id * d)1930 static int __init print_if_true(const struct dmi_system_id *d)
1931 {
1932 printk("%s\n", d->ident);
1933 return 0;
1934 }
1935
1936 /*
1937 * Some Bioses enable the PS/2 mouse (touchpad) at resume, even if it was
1938 * disabled before the suspend. Linux used to get terribly confused by that.
1939 */
broken_ps2_resume(const struct dmi_system_id * d)1940 static int __init broken_ps2_resume(const struct dmi_system_id *d)
1941 {
1942 printk(KERN_INFO "%s machine detected. Mousepad Resume Bug "
1943 "workaround hopefully not needed.\n", d->ident);
1944 return 0;
1945 }
1946
1947 /* Some bioses have a broken protected mode poweroff and need to use realmode */
set_realmode_power_off(const struct dmi_system_id * d)1948 static int __init set_realmode_power_off(const struct dmi_system_id *d)
1949 {
1950 if (apm_info.realmode_power_off == 0) {
1951 apm_info.realmode_power_off = 1;
1952 printk(KERN_INFO "%s bios detected. "
1953 "Using realmode poweroff only.\n", d->ident);
1954 }
1955 return 0;
1956 }
1957
1958 /* Some laptops require interrupts to be enabled during APM calls */
set_apm_ints(const struct dmi_system_id * d)1959 static int __init set_apm_ints(const struct dmi_system_id *d)
1960 {
1961 if (apm_info.allow_ints == 0) {
1962 apm_info.allow_ints = 1;
1963 printk(KERN_INFO "%s machine detected. "
1964 "Enabling interrupts during APM calls.\n", d->ident);
1965 }
1966 return 0;
1967 }
1968
1969 /* Some APM bioses corrupt memory or just plain do not work */
apm_is_horked(const struct dmi_system_id * d)1970 static int __init apm_is_horked(const struct dmi_system_id *d)
1971 {
1972 if (apm_info.disabled == 0) {
1973 apm_info.disabled = 1;
1974 printk(KERN_INFO "%s machine detected. "
1975 "Disabling APM.\n", d->ident);
1976 }
1977 return 0;
1978 }
1979
apm_is_horked_d850md(const struct dmi_system_id * d)1980 static int __init apm_is_horked_d850md(const struct dmi_system_id *d)
1981 {
1982 if (apm_info.disabled == 0) {
1983 apm_info.disabled = 1;
1984 printk(KERN_INFO "%s machine detected. "
1985 "Disabling APM.\n", d->ident);
1986 printk(KERN_INFO "This bug is fixed in bios P15 which is available for\n");
1987 printk(KERN_INFO "download from support.intel.com\n");
1988 }
1989 return 0;
1990 }
1991
1992 /* Some APM bioses hang on APM idle calls */
apm_likes_to_melt(const struct dmi_system_id * d)1993 static int __init apm_likes_to_melt(const struct dmi_system_id *d)
1994 {
1995 if (apm_info.forbid_idle == 0) {
1996 apm_info.forbid_idle = 1;
1997 printk(KERN_INFO "%s machine detected. "
1998 "Disabling APM idle calls.\n", d->ident);
1999 }
2000 return 0;
2001 }
2002
2003 /*
2004 * Check for clue free BIOS implementations who use
2005 * the following QA technique
2006 *
2007 * [ Write BIOS Code ]<------
2008 * | ^
2009 * < Does it Compile >----N--
2010 * |Y ^
2011 * < Does it Boot Win98 >-N--
2012 * |Y
2013 * [Ship It]
2014 *
2015 * Phoenix A04 08/24/2000 is known bad (Dell Inspiron 5000e)
2016 * Phoenix A07 09/29/2000 is known good (Dell Inspiron 5000)
2017 */
broken_apm_power(const struct dmi_system_id * d)2018 static int __init broken_apm_power(const struct dmi_system_id *d)
2019 {
2020 apm_info.get_power_status_broken = 1;
2021 printk(KERN_WARNING "BIOS strings suggest APM bugs, "
2022 "disabling power status reporting.\n");
2023 return 0;
2024 }
2025
2026 /*
2027 * This bios swaps the APM minute reporting bytes over (Many sony laptops
2028 * have this problem).
2029 */
swab_apm_power_in_minutes(const struct dmi_system_id * d)2030 static int __init swab_apm_power_in_minutes(const struct dmi_system_id *d)
2031 {
2032 apm_info.get_power_status_swabinminutes = 1;
2033 printk(KERN_WARNING "BIOS strings suggest APM reports battery life "
2034 "in minutes and wrong byte order.\n");
2035 return 0;
2036 }
2037
2038 static const struct dmi_system_id apm_dmi_table[] __initconst = {
2039 {
2040 print_if_true,
2041 KERN_WARNING "IBM T23 - BIOS 1.03b+ and controller firmware 1.02+ may be needed for Linux APM.",
2042 { DMI_MATCH(DMI_SYS_VENDOR, "IBM"),
2043 DMI_MATCH(DMI_BIOS_VERSION, "1AET38WW (1.01b)"), },
2044 },
2045 { /* Handle problems with APM on the C600 */
2046 broken_ps2_resume, "Dell Latitude C600",
2047 { DMI_MATCH(DMI_SYS_VENDOR, "Dell"),
2048 DMI_MATCH(DMI_PRODUCT_NAME, "Latitude C600"), },
2049 },
2050 { /* Allow interrupts during suspend on Dell Latitude laptops*/
2051 set_apm_ints, "Dell Latitude",
2052 { DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
2053 DMI_MATCH(DMI_PRODUCT_NAME, "Latitude C510"), }
2054 },
2055 { /* APM crashes */
2056 apm_is_horked, "Dell Inspiron 2500",
2057 { DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
2058 DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 2500"),
2059 DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2060 DMI_MATCH(DMI_BIOS_VERSION, "A11"), },
2061 },
2062 { /* Allow interrupts during suspend on Dell Inspiron laptops*/
2063 set_apm_ints, "Dell Inspiron", {
2064 DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
2065 DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 4000"), },
2066 },
2067 { /* Handle problems with APM on Inspiron 5000e */
2068 broken_apm_power, "Dell Inspiron 5000e",
2069 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2070 DMI_MATCH(DMI_BIOS_VERSION, "A04"),
2071 DMI_MATCH(DMI_BIOS_DATE, "08/24/2000"), },
2072 },
2073 { /* Handle problems with APM on Inspiron 2500 */
2074 broken_apm_power, "Dell Inspiron 2500",
2075 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2076 DMI_MATCH(DMI_BIOS_VERSION, "A12"),
2077 DMI_MATCH(DMI_BIOS_DATE, "02/04/2002"), },
2078 },
2079 { /* APM crashes */
2080 apm_is_horked, "Dell Dimension 4100",
2081 { DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
2082 DMI_MATCH(DMI_PRODUCT_NAME, "XPS-Z"),
2083 DMI_MATCH(DMI_BIOS_VENDOR, "Intel Corp."),
2084 DMI_MATCH(DMI_BIOS_VERSION, "A11"), },
2085 },
2086 { /* Allow interrupts during suspend on Compaq Laptops*/
2087 set_apm_ints, "Compaq 12XL125",
2088 { DMI_MATCH(DMI_SYS_VENDOR, "Compaq"),
2089 DMI_MATCH(DMI_PRODUCT_NAME, "Compaq PC"),
2090 DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2091 DMI_MATCH(DMI_BIOS_VERSION, "4.06"), },
2092 },
2093 { /* Allow interrupts during APM or the clock goes slow */
2094 set_apm_ints, "ASUSTeK",
2095 { DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK Computer Inc."),
2096 DMI_MATCH(DMI_PRODUCT_NAME, "L8400K series Notebook PC"), },
2097 },
2098 { /* APM blows on shutdown */
2099 apm_is_horked, "ABIT KX7-333[R]",
2100 { DMI_MATCH(DMI_BOARD_VENDOR, "ABIT"),
2101 DMI_MATCH(DMI_BOARD_NAME, "VT8367-8233A (KX7-333[R])"), },
2102 },
2103 { /* APM crashes */
2104 apm_is_horked, "Trigem Delhi3",
2105 { DMI_MATCH(DMI_SYS_VENDOR, "TriGem Computer, Inc"),
2106 DMI_MATCH(DMI_PRODUCT_NAME, "Delhi3"), },
2107 },
2108 { /* APM crashes */
2109 apm_is_horked, "Fujitsu-Siemens",
2110 { DMI_MATCH(DMI_BIOS_VENDOR, "hoenix/FUJITSU SIEMENS"),
2111 DMI_MATCH(DMI_BIOS_VERSION, "Version1.01"), },
2112 },
2113 { /* APM crashes */
2114 apm_is_horked_d850md, "Intel D850MD",
2115 { DMI_MATCH(DMI_BIOS_VENDOR, "Intel Corp."),
2116 DMI_MATCH(DMI_BIOS_VERSION, "MV85010A.86A.0016.P07.0201251536"), },
2117 },
2118 { /* APM crashes */
2119 apm_is_horked, "Intel D810EMO",
2120 { DMI_MATCH(DMI_BIOS_VENDOR, "Intel Corp."),
2121 DMI_MATCH(DMI_BIOS_VERSION, "MO81010A.86A.0008.P04.0004170800"), },
2122 },
2123 { /* APM crashes */
2124 apm_is_horked, "Dell XPS-Z",
2125 { DMI_MATCH(DMI_BIOS_VENDOR, "Intel Corp."),
2126 DMI_MATCH(DMI_BIOS_VERSION, "A11"),
2127 DMI_MATCH(DMI_PRODUCT_NAME, "XPS-Z"), },
2128 },
2129 { /* APM crashes */
2130 apm_is_horked, "Sharp PC-PJ/AX",
2131 { DMI_MATCH(DMI_SYS_VENDOR, "SHARP"),
2132 DMI_MATCH(DMI_PRODUCT_NAME, "PC-PJ/AX"),
2133 DMI_MATCH(DMI_BIOS_VENDOR, "SystemSoft"),
2134 DMI_MATCH(DMI_BIOS_VERSION, "Version R2.08"), },
2135 },
2136 { /* APM crashes */
2137 apm_is_horked, "Dell Inspiron 2500",
2138 { DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
2139 DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 2500"),
2140 DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2141 DMI_MATCH(DMI_BIOS_VERSION, "A11"), },
2142 },
2143 { /* APM idle hangs */
2144 apm_likes_to_melt, "Jabil AMD",
2145 { DMI_MATCH(DMI_BIOS_VENDOR, "American Megatrends Inc."),
2146 DMI_MATCH(DMI_BIOS_VERSION, "0AASNP06"), },
2147 },
2148 { /* APM idle hangs */
2149 apm_likes_to_melt, "AMI Bios",
2150 { DMI_MATCH(DMI_BIOS_VENDOR, "American Megatrends Inc."),
2151 DMI_MATCH(DMI_BIOS_VERSION, "0AASNP05"), },
2152 },
2153 { /* Handle problems with APM on Sony Vaio PCG-N505X(DE) */
2154 swab_apm_power_in_minutes, "Sony VAIO",
2155 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2156 DMI_MATCH(DMI_BIOS_VERSION, "R0206H"),
2157 DMI_MATCH(DMI_BIOS_DATE, "08/23/99"), },
2158 },
2159 { /* Handle problems with APM on Sony Vaio PCG-N505VX */
2160 swab_apm_power_in_minutes, "Sony VAIO",
2161 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2162 DMI_MATCH(DMI_BIOS_VERSION, "W2K06H0"),
2163 DMI_MATCH(DMI_BIOS_DATE, "02/03/00"), },
2164 },
2165 { /* Handle problems with APM on Sony Vaio PCG-XG29 */
2166 swab_apm_power_in_minutes, "Sony VAIO",
2167 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2168 DMI_MATCH(DMI_BIOS_VERSION, "R0117A0"),
2169 DMI_MATCH(DMI_BIOS_DATE, "04/25/00"), },
2170 },
2171 { /* Handle problems with APM on Sony Vaio PCG-Z600NE */
2172 swab_apm_power_in_minutes, "Sony VAIO",
2173 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2174 DMI_MATCH(DMI_BIOS_VERSION, "R0121Z1"),
2175 DMI_MATCH(DMI_BIOS_DATE, "05/11/00"), },
2176 },
2177 { /* Handle problems with APM on Sony Vaio PCG-Z600NE */
2178 swab_apm_power_in_minutes, "Sony VAIO",
2179 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2180 DMI_MATCH(DMI_BIOS_VERSION, "WME01Z1"),
2181 DMI_MATCH(DMI_BIOS_DATE, "08/11/00"), },
2182 },
2183 { /* Handle problems with APM on Sony Vaio PCG-Z600LEK(DE) */
2184 swab_apm_power_in_minutes, "Sony VAIO",
2185 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2186 DMI_MATCH(DMI_BIOS_VERSION, "R0206Z3"),
2187 DMI_MATCH(DMI_BIOS_DATE, "12/25/00"), },
2188 },
2189 { /* Handle problems with APM on Sony Vaio PCG-Z505LS */
2190 swab_apm_power_in_minutes, "Sony VAIO",
2191 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2192 DMI_MATCH(DMI_BIOS_VERSION, "R0203D0"),
2193 DMI_MATCH(DMI_BIOS_DATE, "05/12/00"), },
2194 },
2195 { /* Handle problems with APM on Sony Vaio PCG-Z505LS */
2196 swab_apm_power_in_minutes, "Sony VAIO",
2197 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2198 DMI_MATCH(DMI_BIOS_VERSION, "R0203Z3"),
2199 DMI_MATCH(DMI_BIOS_DATE, "08/25/00"), },
2200 },
2201 { /* Handle problems with APM on Sony Vaio PCG-Z505LS (with updated BIOS) */
2202 swab_apm_power_in_minutes, "Sony VAIO",
2203 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2204 DMI_MATCH(DMI_BIOS_VERSION, "R0209Z3"),
2205 DMI_MATCH(DMI_BIOS_DATE, "05/12/01"), },
2206 },
2207 { /* Handle problems with APM on Sony Vaio PCG-F104K */
2208 swab_apm_power_in_minutes, "Sony VAIO",
2209 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2210 DMI_MATCH(DMI_BIOS_VERSION, "R0204K2"),
2211 DMI_MATCH(DMI_BIOS_DATE, "08/28/00"), },
2212 },
2213
2214 { /* Handle problems with APM on Sony Vaio PCG-C1VN/C1VE */
2215 swab_apm_power_in_minutes, "Sony VAIO",
2216 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2217 DMI_MATCH(DMI_BIOS_VERSION, "R0208P1"),
2218 DMI_MATCH(DMI_BIOS_DATE, "11/09/00"), },
2219 },
2220 { /* Handle problems with APM on Sony Vaio PCG-C1VE */
2221 swab_apm_power_in_minutes, "Sony VAIO",
2222 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2223 DMI_MATCH(DMI_BIOS_VERSION, "R0204P1"),
2224 DMI_MATCH(DMI_BIOS_DATE, "09/12/00"), },
2225 },
2226 { /* Handle problems with APM on Sony Vaio PCG-C1VE */
2227 swab_apm_power_in_minutes, "Sony VAIO",
2228 { DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
2229 DMI_MATCH(DMI_BIOS_VERSION, "WXPO1Z3"),
2230 DMI_MATCH(DMI_BIOS_DATE, "10/26/01"), },
2231 },
2232 { /* broken PM poweroff bios */
2233 set_realmode_power_off, "Award Software v4.60 PGMA",
2234 { DMI_MATCH(DMI_BIOS_VENDOR, "Award Software International, Inc."),
2235 DMI_MATCH(DMI_BIOS_VERSION, "4.60 PGMA"),
2236 DMI_MATCH(DMI_BIOS_DATE, "134526184"), },
2237 },
2238
2239 /* Generic per vendor APM settings */
2240
2241 { /* Allow interrupts during suspend on IBM laptops */
2242 set_apm_ints, "IBM",
2243 { DMI_MATCH(DMI_SYS_VENDOR, "IBM"), },
2244 },
2245
2246 { }
2247 };
2248
2249 /*
2250 * Just start the APM thread. We do NOT want to do APM BIOS
2251 * calls from anything but the APM thread, if for no other reason
2252 * than the fact that we don't trust the APM BIOS. This way,
2253 * most common APM BIOS problems that lead to protection errors
2254 * etc will have at least some level of being contained...
2255 *
2256 * In short, if something bad happens, at least we have a choice
2257 * of just killing the apm thread..
2258 */
apm_init(void)2259 static int __init apm_init(void)
2260 {
2261 struct desc_struct *gdt;
2262 int err;
2263
2264 dmi_check_system(apm_dmi_table);
2265
2266 if (apm_info.bios.version == 0 || machine_is_olpc()) {
2267 printk(KERN_INFO "apm: BIOS not found.\n");
2268 return -ENODEV;
2269 }
2270 printk(KERN_INFO
2271 "apm: BIOS version %d.%d Flags 0x%02x (Driver version %s)\n",
2272 ((apm_info.bios.version >> 8) & 0xff),
2273 (apm_info.bios.version & 0xff),
2274 apm_info.bios.flags,
2275 driver_version);
2276 if ((apm_info.bios.flags & APM_32_BIT_SUPPORT) == 0) {
2277 printk(KERN_INFO "apm: no 32 bit BIOS support\n");
2278 return -ENODEV;
2279 }
2280
2281 if (allow_ints)
2282 apm_info.allow_ints = 1;
2283 if (broken_psr)
2284 apm_info.get_power_status_broken = 1;
2285 if (realmode_power_off)
2286 apm_info.realmode_power_off = 1;
2287 /* User can override, but default is to trust DMI */
2288 if (apm_disabled != -1)
2289 apm_info.disabled = apm_disabled;
2290
2291 /*
2292 * Fix for the Compaq Contura 3/25c which reports BIOS version 0.1
2293 * but is reportedly a 1.0 BIOS.
2294 */
2295 if (apm_info.bios.version == 0x001)
2296 apm_info.bios.version = 0x100;
2297
2298 /* BIOS < 1.2 doesn't set cseg_16_len */
2299 if (apm_info.bios.version < 0x102)
2300 apm_info.bios.cseg_16_len = 0; /* 64k */
2301
2302 if (debug) {
2303 printk(KERN_INFO "apm: entry %x:%x cseg16 %x dseg %x",
2304 apm_info.bios.cseg, apm_info.bios.offset,
2305 apm_info.bios.cseg_16, apm_info.bios.dseg);
2306 if (apm_info.bios.version > 0x100)
2307 printk(" cseg len %x, dseg len %x",
2308 apm_info.bios.cseg_len,
2309 apm_info.bios.dseg_len);
2310 if (apm_info.bios.version > 0x101)
2311 printk(" cseg16 len %x", apm_info.bios.cseg_16_len);
2312 printk("\n");
2313 }
2314
2315 if (apm_info.disabled) {
2316 pr_notice("disabled on user request.\n");
2317 return -ENODEV;
2318 }
2319 if ((num_online_cpus() > 1) && !power_off && !smp) {
2320 pr_notice("disabled - APM is not SMP safe.\n");
2321 apm_info.disabled = 1;
2322 return -ENODEV;
2323 }
2324 if (!acpi_disabled) {
2325 pr_notice("overridden by ACPI.\n");
2326 apm_info.disabled = 1;
2327 return -ENODEV;
2328 }
2329
2330 /*
2331 * Set up the long jump entry point to the APM BIOS, which is called
2332 * from inline assembly.
2333 */
2334 apm_bios_entry.offset = apm_info.bios.offset;
2335 apm_bios_entry.segment = APM_CS;
2336
2337 /*
2338 * The APM 1.1 BIOS is supposed to provide limit information that it
2339 * recognizes. Many machines do this correctly, but many others do
2340 * not restrict themselves to their claimed limit. When this happens,
2341 * they will cause a segmentation violation in the kernel at boot time.
2342 * Most BIOS's, however, will respect a 64k limit, so we use that.
2343 *
2344 * Note we only set APM segments on CPU zero, since we pin the APM
2345 * code to that CPU.
2346 */
2347 gdt = get_cpu_gdt_rw(0);
2348 set_desc_base(&gdt[APM_CS >> 3],
2349 (unsigned long)__va((unsigned long)apm_info.bios.cseg << 4));
2350 set_desc_base(&gdt[APM_CS_16 >> 3],
2351 (unsigned long)__va((unsigned long)apm_info.bios.cseg_16 << 4));
2352 set_desc_base(&gdt[APM_DS >> 3],
2353 (unsigned long)__va((unsigned long)apm_info.bios.dseg << 4));
2354
2355 proc_create_single("apm", 0, NULL, proc_apm_show);
2356
2357 kapmd_task = kthread_create(apm, NULL, "kapmd");
2358 if (IS_ERR(kapmd_task)) {
2359 pr_err("disabled - Unable to start kernel thread\n");
2360 err = PTR_ERR(kapmd_task);
2361 kapmd_task = NULL;
2362 remove_proc_entry("apm", NULL);
2363 return err;
2364 }
2365 wake_up_process(kapmd_task);
2366
2367 if (num_online_cpus() > 1 && !smp) {
2368 printk(KERN_NOTICE
2369 "apm: disabled - APM is not SMP safe (power off active).\n");
2370 return 0;
2371 }
2372
2373 /*
2374 * Note we don't actually care if the misc_device cannot be registered.
2375 * this driver can do its job without it, even if userspace can't
2376 * control it. just log the error
2377 */
2378 if (misc_register(&apm_device))
2379 printk(KERN_WARNING "apm: Could not register misc device.\n");
2380
2381 if (HZ != 100)
2382 idle_period = (idle_period * HZ) / 100;
2383 if (idle_threshold < 100) {
2384 cpuidle_poll_state_init(&apm_idle_driver);
2385 if (!cpuidle_register_driver(&apm_idle_driver))
2386 if (cpuidle_register_device(&apm_cpuidle_device))
2387 cpuidle_unregister_driver(&apm_idle_driver);
2388 }
2389
2390 return 0;
2391 }
2392
apm_exit(void)2393 static void __exit apm_exit(void)
2394 {
2395 int error;
2396
2397 cpuidle_unregister_device(&apm_cpuidle_device);
2398 cpuidle_unregister_driver(&apm_idle_driver);
2399
2400 if (((apm_info.bios.flags & APM_BIOS_DISENGAGED) == 0)
2401 && (apm_info.connection_version > 0x0100)) {
2402 error = apm_engage_power_management(APM_DEVICE_ALL, 0);
2403 if (error)
2404 apm_error("disengage power management", error);
2405 }
2406 misc_deregister(&apm_device);
2407 remove_proc_entry("apm", NULL);
2408 if (power_off)
2409 pm_power_off = NULL;
2410 if (kapmd_task) {
2411 kthread_stop(kapmd_task);
2412 kapmd_task = NULL;
2413 }
2414 }
2415
2416 module_init(apm_init);
2417 module_exit(apm_exit);
2418
2419 MODULE_AUTHOR("Stephen Rothwell");
2420 MODULE_DESCRIPTION("Advanced Power Management");
2421 MODULE_LICENSE("GPL");
2422 module_param(debug, bool, 0644);
2423 MODULE_PARM_DESC(debug, "Enable debug mode");
2424 module_param(power_off, bool, 0444);
2425 MODULE_PARM_DESC(power_off, "Enable power off");
2426 module_param(bounce_interval, int, 0444);
2427 MODULE_PARM_DESC(bounce_interval,
2428 "Set the number of ticks to ignore suspend bounces");
2429 module_param(allow_ints, bool, 0444);
2430 MODULE_PARM_DESC(allow_ints, "Allow interrupts during BIOS calls");
2431 module_param(broken_psr, bool, 0444);
2432 MODULE_PARM_DESC(broken_psr, "BIOS has a broken GetPowerStatus call");
2433 module_param(realmode_power_off, bool, 0444);
2434 MODULE_PARM_DESC(realmode_power_off,
2435 "Switch to real mode before powering off");
2436 module_param(idle_threshold, int, 0444);
2437 MODULE_PARM_DESC(idle_threshold,
2438 "System idle percentage above which to make APM BIOS idle calls");
2439 module_param(idle_period, int, 0444);
2440 MODULE_PARM_DESC(idle_period,
2441 "Period (in sec/100) over which to calculate the idle percentage");
2442 module_param(smp, bool, 0444);
2443 MODULE_PARM_DESC(smp,
2444 "Set this to enable APM use on an SMP platform. Use with caution on older systems");
2445 MODULE_ALIAS_MISCDEV(APM_MINOR_DEV);
2446