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