Merge branch 'linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes...
[sfrench/cifs-2.6.git] / drivers / acpi / sleep / main.c
1 /*
2  * sleep.c - ACPI sleep support.
3  *
4  * Copyright (c) 2005 Alexey Starikovskiy <alexey.y.starikovskiy@intel.com>
5  * Copyright (c) 2004 David Shaohua Li <shaohua.li@intel.com>
6  * Copyright (c) 2000-2003 Patrick Mochel
7  * Copyright (c) 2003 Open Source Development Lab
8  *
9  * This file is released under the GPLv2.
10  *
11  */
12
13 #include <linux/delay.h>
14 #include <linux/irq.h>
15 #include <linux/dmi.h>
16 #include <linux/device.h>
17 #include <linux/suspend.h>
18
19 #include <asm/io.h>
20
21 #include <acpi/acpi_bus.h>
22 #include <acpi/acpi_drivers.h>
23 #include "sleep.h"
24
25 u8 sleep_states[ACPI_S_STATE_COUNT];
26
27 static int acpi_sleep_prepare(u32 acpi_state)
28 {
29 #ifdef CONFIG_ACPI_SLEEP
30         /* do we have a wakeup address for S2 and S3? */
31         if (acpi_state == ACPI_STATE_S3) {
32                 if (!acpi_wakeup_address) {
33                         return -EFAULT;
34                 }
35                 acpi_set_firmware_waking_vector(
36                                 (acpi_physical_address)acpi_wakeup_address);
37
38         }
39         ACPI_FLUSH_CPU_CACHE();
40         acpi_enable_wakeup_device_prep(acpi_state);
41 #endif
42         printk(KERN_INFO PREFIX "Preparing to enter system sleep state S%d\n",
43                 acpi_state);
44         acpi_enter_sleep_state_prep(acpi_state);
45         return 0;
46 }
47
48 #ifdef CONFIG_PM_SLEEP
49 static u32 acpi_target_sleep_state = ACPI_STATE_S0;
50
51 /*
52  * ACPI 1.0 wants us to execute _PTS before suspending devices, so we allow the
53  * user to request that behavior by using the 'acpi_old_suspend_ordering'
54  * kernel command line option that causes the following variable to be set.
55  */
56 static bool old_suspend_ordering;
57
58 void __init acpi_old_suspend_ordering(void)
59 {
60         old_suspend_ordering = true;
61 }
62
63 /**
64  *      acpi_pm_disable_gpes - Disable the GPEs.
65  */
66 static int acpi_pm_disable_gpes(void)
67 {
68         acpi_hw_disable_all_gpes();
69         return 0;
70 }
71
72 /**
73  *      __acpi_pm_prepare - Prepare the platform to enter the target state.
74  *
75  *      If necessary, set the firmware waking vector and do arch-specific
76  *      nastiness to get the wakeup code to the waking vector.
77  */
78 static int __acpi_pm_prepare(void)
79 {
80         int error = acpi_sleep_prepare(acpi_target_sleep_state);
81
82         if (error)
83                 acpi_target_sleep_state = ACPI_STATE_S0;
84         return error;
85 }
86
87 /**
88  *      acpi_pm_prepare - Prepare the platform to enter the target sleep
89  *              state and disable the GPEs.
90  */
91 static int acpi_pm_prepare(void)
92 {
93         int error = __acpi_pm_prepare();
94
95         if (!error)
96                 acpi_hw_disable_all_gpes();
97         return error;
98 }
99
100 /**
101  *      acpi_pm_finish - Instruct the platform to leave a sleep state.
102  *
103  *      This is called after we wake back up (or if entering the sleep state
104  *      failed).
105  */
106 static void acpi_pm_finish(void)
107 {
108         u32 acpi_state = acpi_target_sleep_state;
109
110         if (acpi_state == ACPI_STATE_S0)
111                 return;
112
113         printk(KERN_INFO PREFIX "Waking up from system sleep state S%d\n",
114                 acpi_state);
115         acpi_disable_wakeup_device(acpi_state);
116         acpi_leave_sleep_state(acpi_state);
117
118         /* reset firmware waking vector */
119         acpi_set_firmware_waking_vector((acpi_physical_address) 0);
120
121         acpi_target_sleep_state = ACPI_STATE_S0;
122 }
123
124 /**
125  *      acpi_pm_end - Finish up suspend sequence.
126  */
127 static void acpi_pm_end(void)
128 {
129         /*
130          * This is necessary in case acpi_pm_finish() is not called during a
131          * failing transition to a sleep state.
132          */
133         acpi_target_sleep_state = ACPI_STATE_S0;
134 }
135 #endif /* CONFIG_PM_SLEEP */
136
137 #ifdef CONFIG_SUSPEND
138 extern void do_suspend_lowlevel(void);
139
140 static u32 acpi_suspend_states[] = {
141         [PM_SUSPEND_ON] = ACPI_STATE_S0,
142         [PM_SUSPEND_STANDBY] = ACPI_STATE_S1,
143         [PM_SUSPEND_MEM] = ACPI_STATE_S3,
144         [PM_SUSPEND_MAX] = ACPI_STATE_S5
145 };
146
147 /**
148  *      acpi_suspend_begin - Set the target system sleep state to the state
149  *              associated with given @pm_state, if supported.
150  */
151 static int acpi_suspend_begin(suspend_state_t pm_state)
152 {
153         u32 acpi_state = acpi_suspend_states[pm_state];
154         int error = 0;
155
156         if (sleep_states[acpi_state]) {
157                 acpi_target_sleep_state = acpi_state;
158         } else {
159                 printk(KERN_ERR "ACPI does not support this state: %d\n",
160                         pm_state);
161                 error = -ENOSYS;
162         }
163         return error;
164 }
165
166 /**
167  *      acpi_suspend_enter - Actually enter a sleep state.
168  *      @pm_state: ignored
169  *
170  *      Flush caches and go to sleep. For STR we have to call arch-specific
171  *      assembly, which in turn call acpi_enter_sleep_state().
172  *      It's unfortunate, but it works. Please fix if you're feeling frisky.
173  */
174 static int acpi_suspend_enter(suspend_state_t pm_state)
175 {
176         acpi_status status = AE_OK;
177         unsigned long flags = 0;
178         u32 acpi_state = acpi_target_sleep_state;
179
180         ACPI_FLUSH_CPU_CACHE();
181
182         /* Do arch specific saving of state. */
183         if (acpi_state == ACPI_STATE_S3) {
184                 int error = acpi_save_state_mem();
185
186                 if (error)
187                         return error;
188         }
189
190         local_irq_save(flags);
191         acpi_enable_wakeup_device(acpi_state);
192         switch (acpi_state) {
193         case ACPI_STATE_S1:
194                 barrier();
195                 status = acpi_enter_sleep_state(acpi_state);
196                 break;
197
198         case ACPI_STATE_S3:
199                 do_suspend_lowlevel();
200                 break;
201         }
202
203         /* Reprogram control registers and execute _BFS */
204         acpi_leave_sleep_state_prep(acpi_state);
205
206         /* ACPI 3.0 specs (P62) says that it's the responsibility
207          * of the OSPM to clear the status bit [ implying that the
208          * POWER_BUTTON event should not reach userspace ]
209          */
210         if (ACPI_SUCCESS(status) && (acpi_state == ACPI_STATE_S3))
211                 acpi_clear_event(ACPI_EVENT_POWER_BUTTON);
212
213         /*
214          * Disable and clear GPE status before interrupt is enabled. Some GPEs
215          * (like wakeup GPE) haven't handler, this can avoid such GPE misfire.
216          * acpi_leave_sleep_state will reenable specific GPEs later
217          */
218         acpi_hw_disable_all_gpes();
219
220         local_irq_restore(flags);
221         printk(KERN_DEBUG "Back to C!\n");
222
223         /* restore processor state */
224         if (acpi_state == ACPI_STATE_S3)
225                 acpi_restore_state_mem();
226
227         return ACPI_SUCCESS(status) ? 0 : -EFAULT;
228 }
229
230 static int acpi_suspend_state_valid(suspend_state_t pm_state)
231 {
232         u32 acpi_state;
233
234         switch (pm_state) {
235         case PM_SUSPEND_ON:
236         case PM_SUSPEND_STANDBY:
237         case PM_SUSPEND_MEM:
238                 acpi_state = acpi_suspend_states[pm_state];
239
240                 return sleep_states[acpi_state];
241         default:
242                 return 0;
243         }
244 }
245
246 static struct platform_suspend_ops acpi_suspend_ops = {
247         .valid = acpi_suspend_state_valid,
248         .begin = acpi_suspend_begin,
249         .prepare = acpi_pm_prepare,
250         .enter = acpi_suspend_enter,
251         .finish = acpi_pm_finish,
252         .end = acpi_pm_end,
253 };
254
255 /**
256  *      acpi_suspend_begin_old - Set the target system sleep state to the
257  *              state associated with given @pm_state, if supported, and
258  *              execute the _PTS control method.  This function is used if the
259  *              pre-ACPI 2.0 suspend ordering has been requested.
260  */
261 static int acpi_suspend_begin_old(suspend_state_t pm_state)
262 {
263         int error = acpi_suspend_begin(pm_state);
264
265         if (!error)
266                 error = __acpi_pm_prepare();
267         return error;
268 }
269
270 /*
271  * The following callbacks are used if the pre-ACPI 2.0 suspend ordering has
272  * been requested.
273  */
274 static struct platform_suspend_ops acpi_suspend_ops_old = {
275         .valid = acpi_suspend_state_valid,
276         .begin = acpi_suspend_begin_old,
277         .prepare = acpi_pm_disable_gpes,
278         .enter = acpi_suspend_enter,
279         .finish = acpi_pm_finish,
280         .end = acpi_pm_end,
281         .recover = acpi_pm_finish,
282 };
283 #endif /* CONFIG_SUSPEND */
284
285 #ifdef CONFIG_HIBERNATION
286 static int acpi_hibernation_begin(void)
287 {
288         acpi_target_sleep_state = ACPI_STATE_S4;
289         return 0;
290 }
291
292 static int acpi_hibernation_enter(void)
293 {
294         acpi_status status = AE_OK;
295         unsigned long flags = 0;
296
297         ACPI_FLUSH_CPU_CACHE();
298
299         local_irq_save(flags);
300         acpi_enable_wakeup_device(ACPI_STATE_S4);
301         /* This shouldn't return.  If it returns, we have a problem */
302         status = acpi_enter_sleep_state(ACPI_STATE_S4);
303         /* Reprogram control registers and execute _BFS */
304         acpi_leave_sleep_state_prep(ACPI_STATE_S4);
305         local_irq_restore(flags);
306
307         return ACPI_SUCCESS(status) ? 0 : -EFAULT;
308 }
309
310 static void acpi_hibernation_leave(void)
311 {
312         /*
313          * If ACPI is not enabled by the BIOS and the boot kernel, we need to
314          * enable it here.
315          */
316         acpi_enable();
317         /* Reprogram control registers and execute _BFS */
318         acpi_leave_sleep_state_prep(ACPI_STATE_S4);
319 }
320
321 static void acpi_pm_enable_gpes(void)
322 {
323         acpi_hw_enable_all_runtime_gpes();
324 }
325
326 static struct platform_hibernation_ops acpi_hibernation_ops = {
327         .begin = acpi_hibernation_begin,
328         .end = acpi_pm_end,
329         .pre_snapshot = acpi_pm_prepare,
330         .finish = acpi_pm_finish,
331         .prepare = acpi_pm_prepare,
332         .enter = acpi_hibernation_enter,
333         .leave = acpi_hibernation_leave,
334         .pre_restore = acpi_pm_disable_gpes,
335         .restore_cleanup = acpi_pm_enable_gpes,
336 };
337
338 /**
339  *      acpi_hibernation_begin_old - Set the target system sleep state to
340  *              ACPI_STATE_S4 and execute the _PTS control method.  This
341  *              function is used if the pre-ACPI 2.0 suspend ordering has been
342  *              requested.
343  */
344 static int acpi_hibernation_begin_old(void)
345 {
346         int error = acpi_sleep_prepare(ACPI_STATE_S4);
347
348         if (!error)
349                 acpi_target_sleep_state = ACPI_STATE_S4;
350         return error;
351 }
352
353 /*
354  * The following callbacks are used if the pre-ACPI 2.0 suspend ordering has
355  * been requested.
356  */
357 static struct platform_hibernation_ops acpi_hibernation_ops_old = {
358         .begin = acpi_hibernation_begin_old,
359         .end = acpi_pm_end,
360         .pre_snapshot = acpi_pm_disable_gpes,
361         .finish = acpi_pm_finish,
362         .prepare = acpi_pm_disable_gpes,
363         .enter = acpi_hibernation_enter,
364         .leave = acpi_hibernation_leave,
365         .pre_restore = acpi_pm_disable_gpes,
366         .restore_cleanup = acpi_pm_enable_gpes,
367         .recover = acpi_pm_finish,
368 };
369 #endif /* CONFIG_HIBERNATION */
370
371 int acpi_suspend(u32 acpi_state)
372 {
373         suspend_state_t states[] = {
374                 [1] = PM_SUSPEND_STANDBY,
375                 [3] = PM_SUSPEND_MEM,
376                 [5] = PM_SUSPEND_MAX
377         };
378
379         if (acpi_state < 6 && states[acpi_state])
380                 return pm_suspend(states[acpi_state]);
381         if (acpi_state == 4)
382                 return hibernate();
383         return -EINVAL;
384 }
385
386 #ifdef CONFIG_PM_SLEEP
387 /**
388  *      acpi_pm_device_sleep_state - return preferred power state of ACPI device
389  *              in the system sleep state given by %acpi_target_sleep_state
390  *      @dev: device to examine; its driver model wakeup flags control
391  *              whether it should be able to wake up the system
392  *      @d_min_p: used to store the upper limit of allowed states range
393  *      Return value: preferred power state of the device on success, -ENODEV on
394  *              failure (ie. if there's no 'struct acpi_device' for @dev)
395  *
396  *      Find the lowest power (highest number) ACPI device power state that
397  *      device @dev can be in while the system is in the sleep state represented
398  *      by %acpi_target_sleep_state.  If @wake is nonzero, the device should be
399  *      able to wake up the system from this sleep state.  If @d_min_p is set,
400  *      the highest power (lowest number) device power state of @dev allowed
401  *      in this system sleep state is stored at the location pointed to by it.
402  *
403  *      The caller must ensure that @dev is valid before using this function.
404  *      The caller is also responsible for figuring out if the device is
405  *      supposed to be able to wake up the system and passing this information
406  *      via @wake.
407  */
408
409 int acpi_pm_device_sleep_state(struct device *dev, int *d_min_p)
410 {
411         acpi_handle handle = DEVICE_ACPI_HANDLE(dev);
412         struct acpi_device *adev;
413         char acpi_method[] = "_SxD";
414         unsigned long d_min, d_max;
415
416         if (!handle || ACPI_FAILURE(acpi_bus_get_device(handle, &adev))) {
417                 printk(KERN_DEBUG "ACPI handle has no context!\n");
418                 return -ENODEV;
419         }
420
421         acpi_method[2] = '0' + acpi_target_sleep_state;
422         /*
423          * If the sleep state is S0, we will return D3, but if the device has
424          * _S0W, we will use the value from _S0W
425          */
426         d_min = ACPI_STATE_D0;
427         d_max = ACPI_STATE_D3;
428
429         /*
430          * If present, _SxD methods return the minimum D-state (highest power
431          * state) we can use for the corresponding S-states.  Otherwise, the
432          * minimum D-state is D0 (ACPI 3.x).
433          *
434          * NOTE: We rely on acpi_evaluate_integer() not clobbering the integer
435          * provided -- that's our fault recovery, we ignore retval.
436          */
437         if (acpi_target_sleep_state > ACPI_STATE_S0)
438                 acpi_evaluate_integer(handle, acpi_method, NULL, &d_min);
439
440         /*
441          * If _PRW says we can wake up the system from the target sleep state,
442          * the D-state returned by _SxD is sufficient for that (we assume a
443          * wakeup-aware driver if wake is set).  Still, if _SxW exists
444          * (ACPI 3.x), it should return the maximum (lowest power) D-state that
445          * can wake the system.  _S0W may be valid, too.
446          */
447         if (acpi_target_sleep_state == ACPI_STATE_S0 ||
448             (device_may_wakeup(dev) && adev->wakeup.state.enabled &&
449              adev->wakeup.sleep_state <= acpi_target_sleep_state)) {
450                 acpi_status status;
451
452                 acpi_method[3] = 'W';
453                 status = acpi_evaluate_integer(handle, acpi_method, NULL,
454                                                 &d_max);
455                 if (ACPI_FAILURE(status)) {
456                         d_max = d_min;
457                 } else if (d_max < d_min) {
458                         /* Warn the user of the broken DSDT */
459                         printk(KERN_WARNING "ACPI: Wrong value from %s\n",
460                                 acpi_method);
461                         /* Sanitize it */
462                         d_min = d_max;
463                 }
464         }
465
466         if (d_min_p)
467                 *d_min_p = d_min;
468         return d_max;
469 }
470
471 /**
472  *      acpi_pm_device_sleep_wake - enable or disable the system wake-up
473  *                                  capability of given device
474  *      @dev: device to handle
475  *      @enable: 'true' - enable, 'false' - disable the wake-up capability
476  */
477 int acpi_pm_device_sleep_wake(struct device *dev, bool enable)
478 {
479         acpi_handle handle;
480         struct acpi_device *adev;
481
482         if (!device_may_wakeup(dev))
483                 return -EINVAL;
484
485         handle = DEVICE_ACPI_HANDLE(dev);
486         if (!handle || ACPI_FAILURE(acpi_bus_get_device(handle, &adev))) {
487                 printk(KERN_DEBUG "ACPI handle has no context!\n");
488                 return -ENODEV;
489         }
490
491         return enable ?
492                 acpi_enable_wakeup_device_power(adev, acpi_target_sleep_state) :
493                 acpi_disable_wakeup_device_power(adev);
494 }
495 #endif
496
497 static void acpi_power_off_prepare(void)
498 {
499         /* Prepare to power off the system */
500         acpi_sleep_prepare(ACPI_STATE_S5);
501         acpi_hw_disable_all_gpes();
502 }
503
504 static void acpi_power_off(void)
505 {
506         /* acpi_sleep_prepare(ACPI_STATE_S5) should have already been called */
507         printk("%s called\n", __func__);
508         local_irq_disable();
509         acpi_enable_wakeup_device(ACPI_STATE_S5);
510         acpi_enter_sleep_state(ACPI_STATE_S5);
511 }
512
513 int __init acpi_sleep_init(void)
514 {
515         acpi_status status;
516         u8 type_a, type_b;
517 #ifdef CONFIG_SUSPEND
518         int i = 0;
519 #endif
520
521         if (acpi_disabled)
522                 return 0;
523
524         sleep_states[ACPI_STATE_S0] = 1;
525         printk(KERN_INFO PREFIX "(supports S0");
526
527 #ifdef CONFIG_SUSPEND
528         for (i = ACPI_STATE_S1; i < ACPI_STATE_S4; i++) {
529                 status = acpi_get_sleep_type_data(i, &type_a, &type_b);
530                 if (ACPI_SUCCESS(status)) {
531                         sleep_states[i] = 1;
532                         printk(" S%d", i);
533                 }
534         }
535
536         suspend_set_ops(old_suspend_ordering ?
537                 &acpi_suspend_ops_old : &acpi_suspend_ops);
538 #endif
539
540 #ifdef CONFIG_HIBERNATION
541         status = acpi_get_sleep_type_data(ACPI_STATE_S4, &type_a, &type_b);
542         if (ACPI_SUCCESS(status)) {
543                 hibernation_set_ops(old_suspend_ordering ?
544                         &acpi_hibernation_ops_old : &acpi_hibernation_ops);
545                 sleep_states[ACPI_STATE_S4] = 1;
546                 printk(" S4");
547         }
548 #endif
549         status = acpi_get_sleep_type_data(ACPI_STATE_S5, &type_a, &type_b);
550         if (ACPI_SUCCESS(status)) {
551                 sleep_states[ACPI_STATE_S5] = 1;
552                 printk(" S5");
553                 pm_power_off_prepare = acpi_power_off_prepare;
554                 pm_power_off = acpi_power_off;
555         }
556         printk(")\n");
557         return 0;
558 }