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1/*
2 * kernel/power/main.c - PM subsystem core functionality.
3 *
4 * Copyright (c) 2003 Patrick Mochel
5 * Copyright (c) 2003 Open Source Development Lab
6 *
7 * This file is released under the GPLv2
8 *
9 */
10
11#include <linux/kobject.h>
12#include <linux/string.h>
13#include <linux/resume-trace.h>
14#include <linux/workqueue.h>
15
16#include "power.h"
17
18DEFINE_MUTEX(pm_mutex);
19
20#ifdef CONFIG_PM_SLEEP
21
22/* Routines for PM-transition notifications */
23
24static BLOCKING_NOTIFIER_HEAD(pm_chain_head);
25
26int register_pm_notifier(struct notifier_block *nb)
27{
28 return blocking_notifier_chain_register(&pm_chain_head, nb);
29}
30EXPORT_SYMBOL_GPL(register_pm_notifier);
31
32int unregister_pm_notifier(struct notifier_block *nb)
33{
34 return blocking_notifier_chain_unregister(&pm_chain_head, nb);
35}
36EXPORT_SYMBOL_GPL(unregister_pm_notifier);
37
38int pm_notifier_call_chain(unsigned long val)
39{
40 int ret = blocking_notifier_call_chain(&pm_chain_head, val, NULL);
41
42 return notifier_to_errno(ret);
43}
44
45/* If set, devices may be suspended and resumed asynchronously. */
46int pm_async_enabled = 1;
47
48static ssize_t pm_async_show(struct kobject *kobj, struct kobj_attribute *attr,
49 char *buf)
50{
51 return sprintf(buf, "%d\n", pm_async_enabled);
52}
53
54static ssize_t pm_async_store(struct kobject *kobj, struct kobj_attribute *attr,
55 const char *buf, size_t n)
56{
57 unsigned long val;
58
59 if (strict_strtoul(buf, 10, &val))
60 return -EINVAL;
61
62 if (val > 1)
63 return -EINVAL;
64
65 pm_async_enabled = val;
66 return n;
67}
68
69power_attr(pm_async);
70
71#ifdef CONFIG_PM_DEBUG
72int pm_test_level = TEST_NONE;
73
74static const char * const pm_tests[__TEST_AFTER_LAST] = {
75 [TEST_NONE] = "none",
76 [TEST_CORE] = "core",
77 [TEST_CPUS] = "processors",
78 [TEST_PLATFORM] = "platform",
79 [TEST_DEVICES] = "devices",
80 [TEST_FREEZER] = "freezer",
81};
82
83static ssize_t pm_test_show(struct kobject *kobj, struct kobj_attribute *attr,
84 char *buf)
85{
86 char *s = buf;
87 int level;
88
89 for (level = TEST_FIRST; level <= TEST_MAX; level++)
90 if (pm_tests[level]) {
91 if (level == pm_test_level)
92 s += sprintf(s, "[%s] ", pm_tests[level]);
93 else
94 s += sprintf(s, "%s ", pm_tests[level]);
95 }
96
97 if (s != buf)
98 /* convert the last space to a newline */
99 *(s-1) = '\n';
100
101 return (s - buf);
102}
103
104static ssize_t pm_test_store(struct kobject *kobj, struct kobj_attribute *attr,
105 const char *buf, size_t n)
106{
107 const char * const *s;
108 int level;
109 char *p;
110 int len;
111 int error = -EINVAL;
112
113 p = memchr(buf, '\n', n);
114 len = p ? p - buf : n;
115
116 mutex_lock(&pm_mutex);
117
118 level = TEST_FIRST;
119 for (s = &pm_tests[level]; level <= TEST_MAX; s++, level++)
120 if (*s && len == strlen(*s) && !strncmp(buf, *s, len)) {
121 pm_test_level = level;
122 error = 0;
123 break;
124 }
125
126 mutex_unlock(&pm_mutex);
127
128 return error ? error : n;
129}
130
131power_attr(pm_test);
132#endif /* CONFIG_PM_DEBUG */
133
134#endif /* CONFIG_PM_SLEEP */
135
136struct kobject *power_kobj;
137
138/**
139 * state - control system power state.
140 *
141 * show() returns what states are supported, which is hard-coded to
142 * 'standby' (Power-On Suspend), 'mem' (Suspend-to-RAM), and
143 * 'disk' (Suspend-to-Disk).
144 *
145 * store() accepts one of those strings, translates it into the
146 * proper enumerated value, and initiates a suspend transition.
147 */
148static ssize_t state_show(struct kobject *kobj, struct kobj_attribute *attr,
149 char *buf)
150{
151 char *s = buf;
152#ifdef CONFIG_SUSPEND
153 int i;
154
155 for (i = 0; i < PM_SUSPEND_MAX; i++) {
156 if (pm_states[i] && valid_state(i))
157 s += sprintf(s,"%s ", pm_states[i]);
158 }
159#endif
160#ifdef CONFIG_HIBERNATION
161 s += sprintf(s, "%s\n", "disk");
162#else
163 if (s != buf)
164 /* convert the last space to a newline */
165 *(s-1) = '\n';
166#endif
167 return (s - buf);
168}
169
170static ssize_t state_store(struct kobject *kobj, struct kobj_attribute *attr,
171 const char *buf, size_t n)
172{
173#ifdef CONFIG_SUSPEND
174 suspend_state_t state = PM_SUSPEND_STANDBY;
175 const char * const *s;
176#endif
177 char *p;
178 int len;
179 int error = -EINVAL;
180
181 p = memchr(buf, '\n', n);
182 len = p ? p - buf : n;
183
184 /* First, check if we are requested to hibernate */
185 if (len == 4 && !strncmp(buf, "disk", len)) {
186 error = hibernate();
187 goto Exit;
188 }
189
190#ifdef CONFIG_SUSPEND
191 for (s = &pm_states[state]; state < PM_SUSPEND_MAX; s++, state++) {
192 if (*s && len == strlen(*s) && !strncmp(buf, *s, len))
193 break;
194 }
195 if (state < PM_SUSPEND_MAX && *s)
196 error = enter_state(state);
197#endif
198
199 Exit:
200 return error ? error : n;
201}
202
203power_attr(state);
204
205#ifdef CONFIG_PM_SLEEP
206/*
207 * The 'wakeup_count' attribute, along with the functions defined in
208 * drivers/base/power/wakeup.c, provides a means by which wakeup events can be
209 * handled in a non-racy way.
210 *
211 * If a wakeup event occurs when the system is in a sleep state, it simply is
212 * woken up. In turn, if an event that would wake the system up from a sleep
213 * state occurs when it is undergoing a transition to that sleep state, the
214 * transition should be aborted. Moreover, if such an event occurs when the
215 * system is in the working state, an attempt to start a transition to the
216 * given sleep state should fail during certain period after the detection of
217 * the event. Using the 'state' attribute alone is not sufficient to satisfy
218 * these requirements, because a wakeup event may occur exactly when 'state'
219 * is being written to and may be delivered to user space right before it is
220 * frozen, so the event will remain only partially processed until the system is
221 * woken up by another event. In particular, it won't cause the transition to
222 * a sleep state to be aborted.
223 *
224 * This difficulty may be overcome if user space uses 'wakeup_count' before
225 * writing to 'state'. It first should read from 'wakeup_count' and store
226 * the read value. Then, after carrying out its own preparations for the system
227 * transition to a sleep state, it should write the stored value to
228 * 'wakeup_count'. If that fails, at least one wakeup event has occurred since
229 * 'wakeup_count' was read and 'state' should not be written to. Otherwise, it
230 * is allowed to write to 'state', but the transition will be aborted if there
231 * are any wakeup events detected after 'wakeup_count' was written to.
232 */
233
234static ssize_t wakeup_count_show(struct kobject *kobj,
235 struct kobj_attribute *attr,
236 char *buf)
237{
238 unsigned int val;
239
240 return pm_get_wakeup_count(&val) ? sprintf(buf, "%u\n", val) : -EINTR;
241}
242
243static ssize_t wakeup_count_store(struct kobject *kobj,
244 struct kobj_attribute *attr,
245 const char *buf, size_t n)
246{
247 unsigned int val;
248
249 if (sscanf(buf, "%u", &val) == 1) {
250 if (pm_save_wakeup_count(val))
251 return n;
252 }
253 return -EINVAL;
254}
255
256power_attr(wakeup_count);
257#endif /* CONFIG_PM_SLEEP */
258
259#ifdef CONFIG_PM_TRACE
260int pm_trace_enabled;
261
262static ssize_t pm_trace_show(struct kobject *kobj, struct kobj_attribute *attr,
263 char *buf)
264{
265 return sprintf(buf, "%d\n", pm_trace_enabled);
266}
267
268static ssize_t
269pm_trace_store(struct kobject *kobj, struct kobj_attribute *attr,
270 const char *buf, size_t n)
271{
272 int val;
273
274 if (sscanf(buf, "%d", &val) == 1) {
275 pm_trace_enabled = !!val;
276 return n;
277 }
278 return -EINVAL;
279}
280
281power_attr(pm_trace);
282
283static ssize_t pm_trace_dev_match_show(struct kobject *kobj,
284 struct kobj_attribute *attr,
285 char *buf)
286{
287 return show_trace_dev_match(buf, PAGE_SIZE);
288}
289
290static ssize_t
291pm_trace_dev_match_store(struct kobject *kobj, struct kobj_attribute *attr,
292 const char *buf, size_t n)
293{
294 return -EINVAL;
295}
296
297power_attr(pm_trace_dev_match);
298
299#endif /* CONFIG_PM_TRACE */
300
301static struct attribute * g[] = {
302 &state_attr.attr,
303#ifdef CONFIG_PM_TRACE
304 &pm_trace_attr.attr,
305 &pm_trace_dev_match_attr.attr,
306#endif
307#ifdef CONFIG_PM_SLEEP
308 &pm_async_attr.attr,
309 &wakeup_count_attr.attr,
310#ifdef CONFIG_PM_DEBUG
311 &pm_test_attr.attr,
312#endif
313#endif
314 NULL,
315};
316
317static struct attribute_group attr_group = {
318 .attrs = g,
319};
320
321#ifdef CONFIG_PM_RUNTIME
322struct workqueue_struct *pm_wq;
323EXPORT_SYMBOL_GPL(pm_wq);
324
325static int __init pm_start_workqueue(void)
326{
327 pm_wq = alloc_workqueue("pm", WQ_FREEZABLE, 0);
328
329 return pm_wq ? 0 : -ENOMEM;
330}
331#else
332static inline int pm_start_workqueue(void) { return 0; }
333#endif
334
335static int __init pm_init(void)
336{
337 int error = pm_start_workqueue();
338 if (error)
339 return error;
340 hibernate_image_size_init();
341 hibernate_reserved_size_init();
342 power_kobj = kobject_create_and_add("power", NULL);
343 if (!power_kobj)
344 return -ENOMEM;
345 return sysfs_create_group(power_kobj, &attr_group);
346}
347
348core_initcall(pm_init);
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * kernel/power/main.c - PM subsystem core functionality.
4 *
5 * Copyright (c) 2003 Patrick Mochel
6 * Copyright (c) 2003 Open Source Development Lab
7 */
8
9#include <linux/acpi.h>
10#include <linux/export.h>
11#include <linux/kobject.h>
12#include <linux/string.h>
13#include <linux/pm-trace.h>
14#include <linux/workqueue.h>
15#include <linux/debugfs.h>
16#include <linux/seq_file.h>
17#include <linux/suspend.h>
18#include <linux/syscalls.h>
19#include <linux/pm_runtime.h>
20
21#include "power.h"
22
23#ifdef CONFIG_PM_SLEEP
24/*
25 * The following functions are used by the suspend/hibernate code to temporarily
26 * change gfp_allowed_mask in order to avoid using I/O during memory allocations
27 * while devices are suspended. To avoid races with the suspend/hibernate code,
28 * they should always be called with system_transition_mutex held
29 * (gfp_allowed_mask also should only be modified with system_transition_mutex
30 * held, unless the suspend/hibernate code is guaranteed not to run in parallel
31 * with that modification).
32 */
33static gfp_t saved_gfp_mask;
34
35void pm_restore_gfp_mask(void)
36{
37 WARN_ON(!mutex_is_locked(&system_transition_mutex));
38 if (saved_gfp_mask) {
39 gfp_allowed_mask = saved_gfp_mask;
40 saved_gfp_mask = 0;
41 }
42}
43
44void pm_restrict_gfp_mask(void)
45{
46 WARN_ON(!mutex_is_locked(&system_transition_mutex));
47 WARN_ON(saved_gfp_mask);
48 saved_gfp_mask = gfp_allowed_mask;
49 gfp_allowed_mask &= ~(__GFP_IO | __GFP_FS);
50}
51
52unsigned int lock_system_sleep(void)
53{
54 unsigned int flags = current->flags;
55 current->flags |= PF_NOFREEZE;
56 mutex_lock(&system_transition_mutex);
57 return flags;
58}
59EXPORT_SYMBOL_GPL(lock_system_sleep);
60
61void unlock_system_sleep(unsigned int flags)
62{
63 if (!(flags & PF_NOFREEZE))
64 current->flags &= ~PF_NOFREEZE;
65 mutex_unlock(&system_transition_mutex);
66}
67EXPORT_SYMBOL_GPL(unlock_system_sleep);
68
69void ksys_sync_helper(void)
70{
71 ktime_t start;
72 long elapsed_msecs;
73
74 start = ktime_get();
75 ksys_sync();
76 elapsed_msecs = ktime_to_ms(ktime_sub(ktime_get(), start));
77 pr_info("Filesystems sync: %ld.%03ld seconds\n",
78 elapsed_msecs / MSEC_PER_SEC, elapsed_msecs % MSEC_PER_SEC);
79}
80EXPORT_SYMBOL_GPL(ksys_sync_helper);
81
82/* Routines for PM-transition notifications */
83
84static BLOCKING_NOTIFIER_HEAD(pm_chain_head);
85
86int register_pm_notifier(struct notifier_block *nb)
87{
88 return blocking_notifier_chain_register(&pm_chain_head, nb);
89}
90EXPORT_SYMBOL_GPL(register_pm_notifier);
91
92int unregister_pm_notifier(struct notifier_block *nb)
93{
94 return blocking_notifier_chain_unregister(&pm_chain_head, nb);
95}
96EXPORT_SYMBOL_GPL(unregister_pm_notifier);
97
98int pm_notifier_call_chain_robust(unsigned long val_up, unsigned long val_down)
99{
100 int ret;
101
102 ret = blocking_notifier_call_chain_robust(&pm_chain_head, val_up, val_down, NULL);
103
104 return notifier_to_errno(ret);
105}
106
107int pm_notifier_call_chain(unsigned long val)
108{
109 return blocking_notifier_call_chain(&pm_chain_head, val, NULL);
110}
111
112/* If set, devices may be suspended and resumed asynchronously. */
113int pm_async_enabled = 1;
114
115static ssize_t pm_async_show(struct kobject *kobj, struct kobj_attribute *attr,
116 char *buf)
117{
118 return sprintf(buf, "%d\n", pm_async_enabled);
119}
120
121static ssize_t pm_async_store(struct kobject *kobj, struct kobj_attribute *attr,
122 const char *buf, size_t n)
123{
124 unsigned long val;
125
126 if (kstrtoul(buf, 10, &val))
127 return -EINVAL;
128
129 if (val > 1)
130 return -EINVAL;
131
132 pm_async_enabled = val;
133 return n;
134}
135
136power_attr(pm_async);
137
138#ifdef CONFIG_SUSPEND
139static ssize_t mem_sleep_show(struct kobject *kobj, struct kobj_attribute *attr,
140 char *buf)
141{
142 char *s = buf;
143 suspend_state_t i;
144
145 for (i = PM_SUSPEND_MIN; i < PM_SUSPEND_MAX; i++) {
146 if (i >= PM_SUSPEND_MEM && cxl_mem_active())
147 continue;
148 if (mem_sleep_states[i]) {
149 const char *label = mem_sleep_states[i];
150
151 if (mem_sleep_current == i)
152 s += sprintf(s, "[%s] ", label);
153 else
154 s += sprintf(s, "%s ", label);
155 }
156 }
157
158 /* Convert the last space to a newline if needed. */
159 if (s != buf)
160 *(s-1) = '\n';
161
162 return (s - buf);
163}
164
165static suspend_state_t decode_suspend_state(const char *buf, size_t n)
166{
167 suspend_state_t state;
168 char *p;
169 int len;
170
171 p = memchr(buf, '\n', n);
172 len = p ? p - buf : n;
173
174 for (state = PM_SUSPEND_MIN; state < PM_SUSPEND_MAX; state++) {
175 const char *label = mem_sleep_states[state];
176
177 if (label && len == strlen(label) && !strncmp(buf, label, len))
178 return state;
179 }
180
181 return PM_SUSPEND_ON;
182}
183
184static ssize_t mem_sleep_store(struct kobject *kobj, struct kobj_attribute *attr,
185 const char *buf, size_t n)
186{
187 suspend_state_t state;
188 int error;
189
190 error = pm_autosleep_lock();
191 if (error)
192 return error;
193
194 if (pm_autosleep_state() > PM_SUSPEND_ON) {
195 error = -EBUSY;
196 goto out;
197 }
198
199 state = decode_suspend_state(buf, n);
200 if (state < PM_SUSPEND_MAX && state > PM_SUSPEND_ON)
201 mem_sleep_current = state;
202 else
203 error = -EINVAL;
204
205 out:
206 pm_autosleep_unlock();
207 return error ? error : n;
208}
209
210power_attr(mem_sleep);
211
212/*
213 * sync_on_suspend: invoke ksys_sync_helper() before suspend.
214 *
215 * show() returns whether ksys_sync_helper() is invoked before suspend.
216 * store() accepts 0 or 1. 0 disables ksys_sync_helper() and 1 enables it.
217 */
218bool sync_on_suspend_enabled = !IS_ENABLED(CONFIG_SUSPEND_SKIP_SYNC);
219
220static ssize_t sync_on_suspend_show(struct kobject *kobj,
221 struct kobj_attribute *attr, char *buf)
222{
223 return sprintf(buf, "%d\n", sync_on_suspend_enabled);
224}
225
226static ssize_t sync_on_suspend_store(struct kobject *kobj,
227 struct kobj_attribute *attr,
228 const char *buf, size_t n)
229{
230 unsigned long val;
231
232 if (kstrtoul(buf, 10, &val))
233 return -EINVAL;
234
235 if (val > 1)
236 return -EINVAL;
237
238 sync_on_suspend_enabled = !!val;
239 return n;
240}
241
242power_attr(sync_on_suspend);
243#endif /* CONFIG_SUSPEND */
244
245#ifdef CONFIG_PM_SLEEP_DEBUG
246int pm_test_level = TEST_NONE;
247
248static const char * const pm_tests[__TEST_AFTER_LAST] = {
249 [TEST_NONE] = "none",
250 [TEST_CORE] = "core",
251 [TEST_CPUS] = "processors",
252 [TEST_PLATFORM] = "platform",
253 [TEST_DEVICES] = "devices",
254 [TEST_FREEZER] = "freezer",
255};
256
257static ssize_t pm_test_show(struct kobject *kobj, struct kobj_attribute *attr,
258 char *buf)
259{
260 char *s = buf;
261 int level;
262
263 for (level = TEST_FIRST; level <= TEST_MAX; level++)
264 if (pm_tests[level]) {
265 if (level == pm_test_level)
266 s += sprintf(s, "[%s] ", pm_tests[level]);
267 else
268 s += sprintf(s, "%s ", pm_tests[level]);
269 }
270
271 if (s != buf)
272 /* convert the last space to a newline */
273 *(s-1) = '\n';
274
275 return (s - buf);
276}
277
278static ssize_t pm_test_store(struct kobject *kobj, struct kobj_attribute *attr,
279 const char *buf, size_t n)
280{
281 unsigned int sleep_flags;
282 const char * const *s;
283 int error = -EINVAL;
284 int level;
285 char *p;
286 int len;
287
288 p = memchr(buf, '\n', n);
289 len = p ? p - buf : n;
290
291 sleep_flags = lock_system_sleep();
292
293 level = TEST_FIRST;
294 for (s = &pm_tests[level]; level <= TEST_MAX; s++, level++)
295 if (*s && len == strlen(*s) && !strncmp(buf, *s, len)) {
296 pm_test_level = level;
297 error = 0;
298 break;
299 }
300
301 unlock_system_sleep(sleep_flags);
302
303 return error ? error : n;
304}
305
306power_attr(pm_test);
307#endif /* CONFIG_PM_SLEEP_DEBUG */
308
309#define SUSPEND_NR_STEPS SUSPEND_RESUME
310#define REC_FAILED_NUM 2
311
312struct suspend_stats {
313 unsigned int step_failures[SUSPEND_NR_STEPS];
314 unsigned int success;
315 unsigned int fail;
316 int last_failed_dev;
317 char failed_devs[REC_FAILED_NUM][40];
318 int last_failed_errno;
319 int errno[REC_FAILED_NUM];
320 int last_failed_step;
321 u64 last_hw_sleep;
322 u64 total_hw_sleep;
323 u64 max_hw_sleep;
324 enum suspend_stat_step failed_steps[REC_FAILED_NUM];
325};
326
327static struct suspend_stats suspend_stats;
328static DEFINE_MUTEX(suspend_stats_lock);
329
330void dpm_save_failed_dev(const char *name)
331{
332 mutex_lock(&suspend_stats_lock);
333
334 strscpy(suspend_stats.failed_devs[suspend_stats.last_failed_dev],
335 name, sizeof(suspend_stats.failed_devs[0]));
336 suspend_stats.last_failed_dev++;
337 suspend_stats.last_failed_dev %= REC_FAILED_NUM;
338
339 mutex_unlock(&suspend_stats_lock);
340}
341
342void dpm_save_failed_step(enum suspend_stat_step step)
343{
344 suspend_stats.step_failures[step-1]++;
345 suspend_stats.failed_steps[suspend_stats.last_failed_step] = step;
346 suspend_stats.last_failed_step++;
347 suspend_stats.last_failed_step %= REC_FAILED_NUM;
348}
349
350void dpm_save_errno(int err)
351{
352 if (!err) {
353 suspend_stats.success++;
354 return;
355 }
356
357 suspend_stats.fail++;
358
359 suspend_stats.errno[suspend_stats.last_failed_errno] = err;
360 suspend_stats.last_failed_errno++;
361 suspend_stats.last_failed_errno %= REC_FAILED_NUM;
362}
363
364void pm_report_hw_sleep_time(u64 t)
365{
366 suspend_stats.last_hw_sleep = t;
367 suspend_stats.total_hw_sleep += t;
368}
369EXPORT_SYMBOL_GPL(pm_report_hw_sleep_time);
370
371void pm_report_max_hw_sleep(u64 t)
372{
373 suspend_stats.max_hw_sleep = t;
374}
375EXPORT_SYMBOL_GPL(pm_report_max_hw_sleep);
376
377static const char * const suspend_step_names[] = {
378 [SUSPEND_WORKING] = "",
379 [SUSPEND_FREEZE] = "freeze",
380 [SUSPEND_PREPARE] = "prepare",
381 [SUSPEND_SUSPEND] = "suspend",
382 [SUSPEND_SUSPEND_LATE] = "suspend_late",
383 [SUSPEND_SUSPEND_NOIRQ] = "suspend_noirq",
384 [SUSPEND_RESUME_NOIRQ] = "resume_noirq",
385 [SUSPEND_RESUME_EARLY] = "resume_early",
386 [SUSPEND_RESUME] = "resume",
387};
388
389#define suspend_attr(_name, format_str) \
390static ssize_t _name##_show(struct kobject *kobj, \
391 struct kobj_attribute *attr, char *buf) \
392{ \
393 return sprintf(buf, format_str, suspend_stats._name); \
394} \
395static struct kobj_attribute _name = __ATTR_RO(_name)
396
397suspend_attr(success, "%u\n");
398suspend_attr(fail, "%u\n");
399suspend_attr(last_hw_sleep, "%llu\n");
400suspend_attr(total_hw_sleep, "%llu\n");
401suspend_attr(max_hw_sleep, "%llu\n");
402
403#define suspend_step_attr(_name, step) \
404static ssize_t _name##_show(struct kobject *kobj, \
405 struct kobj_attribute *attr, char *buf) \
406{ \
407 return sprintf(buf, "%u\n", \
408 suspend_stats.step_failures[step-1]); \
409} \
410static struct kobj_attribute _name = __ATTR_RO(_name)
411
412suspend_step_attr(failed_freeze, SUSPEND_FREEZE);
413suspend_step_attr(failed_prepare, SUSPEND_PREPARE);
414suspend_step_attr(failed_suspend, SUSPEND_SUSPEND);
415suspend_step_attr(failed_suspend_late, SUSPEND_SUSPEND_LATE);
416suspend_step_attr(failed_suspend_noirq, SUSPEND_SUSPEND_NOIRQ);
417suspend_step_attr(failed_resume, SUSPEND_RESUME);
418suspend_step_attr(failed_resume_early, SUSPEND_RESUME_EARLY);
419suspend_step_attr(failed_resume_noirq, SUSPEND_RESUME_NOIRQ);
420
421static ssize_t last_failed_dev_show(struct kobject *kobj,
422 struct kobj_attribute *attr, char *buf)
423{
424 int index;
425 char *last_failed_dev = NULL;
426
427 index = suspend_stats.last_failed_dev + REC_FAILED_NUM - 1;
428 index %= REC_FAILED_NUM;
429 last_failed_dev = suspend_stats.failed_devs[index];
430
431 return sprintf(buf, "%s\n", last_failed_dev);
432}
433static struct kobj_attribute last_failed_dev = __ATTR_RO(last_failed_dev);
434
435static ssize_t last_failed_errno_show(struct kobject *kobj,
436 struct kobj_attribute *attr, char *buf)
437{
438 int index;
439 int last_failed_errno;
440
441 index = suspend_stats.last_failed_errno + REC_FAILED_NUM - 1;
442 index %= REC_FAILED_NUM;
443 last_failed_errno = suspend_stats.errno[index];
444
445 return sprintf(buf, "%d\n", last_failed_errno);
446}
447static struct kobj_attribute last_failed_errno = __ATTR_RO(last_failed_errno);
448
449static ssize_t last_failed_step_show(struct kobject *kobj,
450 struct kobj_attribute *attr, char *buf)
451{
452 enum suspend_stat_step step;
453 int index;
454
455 index = suspend_stats.last_failed_step + REC_FAILED_NUM - 1;
456 index %= REC_FAILED_NUM;
457 step = suspend_stats.failed_steps[index];
458
459 return sprintf(buf, "%s\n", suspend_step_names[step]);
460}
461static struct kobj_attribute last_failed_step = __ATTR_RO(last_failed_step);
462
463static struct attribute *suspend_attrs[] = {
464 &success.attr,
465 &fail.attr,
466 &failed_freeze.attr,
467 &failed_prepare.attr,
468 &failed_suspend.attr,
469 &failed_suspend_late.attr,
470 &failed_suspend_noirq.attr,
471 &failed_resume.attr,
472 &failed_resume_early.attr,
473 &failed_resume_noirq.attr,
474 &last_failed_dev.attr,
475 &last_failed_errno.attr,
476 &last_failed_step.attr,
477 &last_hw_sleep.attr,
478 &total_hw_sleep.attr,
479 &max_hw_sleep.attr,
480 NULL,
481};
482
483static umode_t suspend_attr_is_visible(struct kobject *kobj, struct attribute *attr, int idx)
484{
485 if (attr != &last_hw_sleep.attr &&
486 attr != &total_hw_sleep.attr &&
487 attr != &max_hw_sleep.attr)
488 return 0444;
489
490#ifdef CONFIG_ACPI
491 if (acpi_gbl_FADT.flags & ACPI_FADT_LOW_POWER_S0)
492 return 0444;
493#endif
494 return 0;
495}
496
497static const struct attribute_group suspend_attr_group = {
498 .name = "suspend_stats",
499 .attrs = suspend_attrs,
500 .is_visible = suspend_attr_is_visible,
501};
502
503#ifdef CONFIG_DEBUG_FS
504static int suspend_stats_show(struct seq_file *s, void *unused)
505{
506 int i, index, last_dev, last_errno, last_step;
507 enum suspend_stat_step step;
508
509 last_dev = suspend_stats.last_failed_dev + REC_FAILED_NUM - 1;
510 last_dev %= REC_FAILED_NUM;
511 last_errno = suspend_stats.last_failed_errno + REC_FAILED_NUM - 1;
512 last_errno %= REC_FAILED_NUM;
513 last_step = suspend_stats.last_failed_step + REC_FAILED_NUM - 1;
514 last_step %= REC_FAILED_NUM;
515
516 seq_printf(s, "success: %u\nfail: %u\n",
517 suspend_stats.success, suspend_stats.fail);
518
519 for (step = SUSPEND_FREEZE; step <= SUSPEND_NR_STEPS; step++)
520 seq_printf(s, "failed_%s: %u\n", suspend_step_names[step],
521 suspend_stats.step_failures[step-1]);
522
523 seq_printf(s, "failures:\n last_failed_dev:\t%-s\n",
524 suspend_stats.failed_devs[last_dev]);
525 for (i = 1; i < REC_FAILED_NUM; i++) {
526 index = last_dev + REC_FAILED_NUM - i;
527 index %= REC_FAILED_NUM;
528 seq_printf(s, "\t\t\t%-s\n", suspend_stats.failed_devs[index]);
529 }
530 seq_printf(s, " last_failed_errno:\t%-d\n",
531 suspend_stats.errno[last_errno]);
532 for (i = 1; i < REC_FAILED_NUM; i++) {
533 index = last_errno + REC_FAILED_NUM - i;
534 index %= REC_FAILED_NUM;
535 seq_printf(s, "\t\t\t%-d\n", suspend_stats.errno[index]);
536 }
537 seq_printf(s, " last_failed_step:\t%-s\n",
538 suspend_step_names[suspend_stats.failed_steps[last_step]]);
539 for (i = 1; i < REC_FAILED_NUM; i++) {
540 index = last_step + REC_FAILED_NUM - i;
541 index %= REC_FAILED_NUM;
542 seq_printf(s, "\t\t\t%-s\n",
543 suspend_step_names[suspend_stats.failed_steps[index]]);
544 }
545
546 return 0;
547}
548DEFINE_SHOW_ATTRIBUTE(suspend_stats);
549
550static int __init pm_debugfs_init(void)
551{
552 debugfs_create_file("suspend_stats", S_IFREG | S_IRUGO,
553 NULL, NULL, &suspend_stats_fops);
554 return 0;
555}
556
557late_initcall(pm_debugfs_init);
558#endif /* CONFIG_DEBUG_FS */
559
560#endif /* CONFIG_PM_SLEEP */
561
562#ifdef CONFIG_PM_SLEEP_DEBUG
563/*
564 * pm_print_times: print time taken by devices to suspend and resume.
565 *
566 * show() returns whether printing of suspend and resume times is enabled.
567 * store() accepts 0 or 1. 0 disables printing and 1 enables it.
568 */
569bool pm_print_times_enabled;
570
571static ssize_t pm_print_times_show(struct kobject *kobj,
572 struct kobj_attribute *attr, char *buf)
573{
574 return sprintf(buf, "%d\n", pm_print_times_enabled);
575}
576
577static ssize_t pm_print_times_store(struct kobject *kobj,
578 struct kobj_attribute *attr,
579 const char *buf, size_t n)
580{
581 unsigned long val;
582
583 if (kstrtoul(buf, 10, &val))
584 return -EINVAL;
585
586 if (val > 1)
587 return -EINVAL;
588
589 pm_print_times_enabled = !!val;
590 return n;
591}
592
593power_attr(pm_print_times);
594
595static inline void pm_print_times_init(void)
596{
597 pm_print_times_enabled = !!initcall_debug;
598}
599
600static ssize_t pm_wakeup_irq_show(struct kobject *kobj,
601 struct kobj_attribute *attr,
602 char *buf)
603{
604 if (!pm_wakeup_irq())
605 return -ENODATA;
606
607 return sprintf(buf, "%u\n", pm_wakeup_irq());
608}
609
610power_attr_ro(pm_wakeup_irq);
611
612bool pm_debug_messages_on __read_mostly;
613
614bool pm_debug_messages_should_print(void)
615{
616 return pm_debug_messages_on && pm_suspend_target_state != PM_SUSPEND_ON;
617}
618EXPORT_SYMBOL_GPL(pm_debug_messages_should_print);
619
620static ssize_t pm_debug_messages_show(struct kobject *kobj,
621 struct kobj_attribute *attr, char *buf)
622{
623 return sprintf(buf, "%d\n", pm_debug_messages_on);
624}
625
626static ssize_t pm_debug_messages_store(struct kobject *kobj,
627 struct kobj_attribute *attr,
628 const char *buf, size_t n)
629{
630 unsigned long val;
631
632 if (kstrtoul(buf, 10, &val))
633 return -EINVAL;
634
635 if (val > 1)
636 return -EINVAL;
637
638 pm_debug_messages_on = !!val;
639 return n;
640}
641
642power_attr(pm_debug_messages);
643
644static int __init pm_debug_messages_setup(char *str)
645{
646 pm_debug_messages_on = true;
647 return 1;
648}
649__setup("pm_debug_messages", pm_debug_messages_setup);
650
651#else /* !CONFIG_PM_SLEEP_DEBUG */
652static inline void pm_print_times_init(void) {}
653#endif /* CONFIG_PM_SLEEP_DEBUG */
654
655struct kobject *power_kobj;
656
657/*
658 * state - control system sleep states.
659 *
660 * show() returns available sleep state labels, which may be "mem", "standby",
661 * "freeze" and "disk" (hibernation).
662 * See Documentation/admin-guide/pm/sleep-states.rst for a description of
663 * what they mean.
664 *
665 * store() accepts one of those strings, translates it into the proper
666 * enumerated value, and initiates a suspend transition.
667 */
668static ssize_t state_show(struct kobject *kobj, struct kobj_attribute *attr,
669 char *buf)
670{
671 char *s = buf;
672#ifdef CONFIG_SUSPEND
673 suspend_state_t i;
674
675 for (i = PM_SUSPEND_MIN; i < PM_SUSPEND_MAX; i++)
676 if (pm_states[i])
677 s += sprintf(s,"%s ", pm_states[i]);
678
679#endif
680 if (hibernation_available())
681 s += sprintf(s, "disk ");
682 if (s != buf)
683 /* convert the last space to a newline */
684 *(s-1) = '\n';
685 return (s - buf);
686}
687
688static suspend_state_t decode_state(const char *buf, size_t n)
689{
690#ifdef CONFIG_SUSPEND
691 suspend_state_t state;
692#endif
693 char *p;
694 int len;
695
696 p = memchr(buf, '\n', n);
697 len = p ? p - buf : n;
698
699 /* Check hibernation first. */
700 if (len == 4 && str_has_prefix(buf, "disk"))
701 return PM_SUSPEND_MAX;
702
703#ifdef CONFIG_SUSPEND
704 for (state = PM_SUSPEND_MIN; state < PM_SUSPEND_MAX; state++) {
705 const char *label = pm_states[state];
706
707 if (label && len == strlen(label) && !strncmp(buf, label, len))
708 return state;
709 }
710#endif
711
712 return PM_SUSPEND_ON;
713}
714
715static ssize_t state_store(struct kobject *kobj, struct kobj_attribute *attr,
716 const char *buf, size_t n)
717{
718 suspend_state_t state;
719 int error;
720
721 error = pm_autosleep_lock();
722 if (error)
723 return error;
724
725 if (pm_autosleep_state() > PM_SUSPEND_ON) {
726 error = -EBUSY;
727 goto out;
728 }
729
730 state = decode_state(buf, n);
731 if (state < PM_SUSPEND_MAX) {
732 if (state == PM_SUSPEND_MEM)
733 state = mem_sleep_current;
734
735 error = pm_suspend(state);
736 } else if (state == PM_SUSPEND_MAX) {
737 error = hibernate();
738 } else {
739 error = -EINVAL;
740 }
741
742 out:
743 pm_autosleep_unlock();
744 return error ? error : n;
745}
746
747power_attr(state);
748
749#ifdef CONFIG_PM_SLEEP
750/*
751 * The 'wakeup_count' attribute, along with the functions defined in
752 * drivers/base/power/wakeup.c, provides a means by which wakeup events can be
753 * handled in a non-racy way.
754 *
755 * If a wakeup event occurs when the system is in a sleep state, it simply is
756 * woken up. In turn, if an event that would wake the system up from a sleep
757 * state occurs when it is undergoing a transition to that sleep state, the
758 * transition should be aborted. Moreover, if such an event occurs when the
759 * system is in the working state, an attempt to start a transition to the
760 * given sleep state should fail during certain period after the detection of
761 * the event. Using the 'state' attribute alone is not sufficient to satisfy
762 * these requirements, because a wakeup event may occur exactly when 'state'
763 * is being written to and may be delivered to user space right before it is
764 * frozen, so the event will remain only partially processed until the system is
765 * woken up by another event. In particular, it won't cause the transition to
766 * a sleep state to be aborted.
767 *
768 * This difficulty may be overcome if user space uses 'wakeup_count' before
769 * writing to 'state'. It first should read from 'wakeup_count' and store
770 * the read value. Then, after carrying out its own preparations for the system
771 * transition to a sleep state, it should write the stored value to
772 * 'wakeup_count'. If that fails, at least one wakeup event has occurred since
773 * 'wakeup_count' was read and 'state' should not be written to. Otherwise, it
774 * is allowed to write to 'state', but the transition will be aborted if there
775 * are any wakeup events detected after 'wakeup_count' was written to.
776 */
777
778static ssize_t wakeup_count_show(struct kobject *kobj,
779 struct kobj_attribute *attr,
780 char *buf)
781{
782 unsigned int val;
783
784 return pm_get_wakeup_count(&val, true) ?
785 sprintf(buf, "%u\n", val) : -EINTR;
786}
787
788static ssize_t wakeup_count_store(struct kobject *kobj,
789 struct kobj_attribute *attr,
790 const char *buf, size_t n)
791{
792 unsigned int val;
793 int error;
794
795 error = pm_autosleep_lock();
796 if (error)
797 return error;
798
799 if (pm_autosleep_state() > PM_SUSPEND_ON) {
800 error = -EBUSY;
801 goto out;
802 }
803
804 error = -EINVAL;
805 if (sscanf(buf, "%u", &val) == 1) {
806 if (pm_save_wakeup_count(val))
807 error = n;
808 else
809 pm_print_active_wakeup_sources();
810 }
811
812 out:
813 pm_autosleep_unlock();
814 return error;
815}
816
817power_attr(wakeup_count);
818
819#ifdef CONFIG_PM_AUTOSLEEP
820static ssize_t autosleep_show(struct kobject *kobj,
821 struct kobj_attribute *attr,
822 char *buf)
823{
824 suspend_state_t state = pm_autosleep_state();
825
826 if (state == PM_SUSPEND_ON)
827 return sprintf(buf, "off\n");
828
829#ifdef CONFIG_SUSPEND
830 if (state < PM_SUSPEND_MAX)
831 return sprintf(buf, "%s\n", pm_states[state] ?
832 pm_states[state] : "error");
833#endif
834#ifdef CONFIG_HIBERNATION
835 return sprintf(buf, "disk\n");
836#else
837 return sprintf(buf, "error");
838#endif
839}
840
841static ssize_t autosleep_store(struct kobject *kobj,
842 struct kobj_attribute *attr,
843 const char *buf, size_t n)
844{
845 suspend_state_t state = decode_state(buf, n);
846 int error;
847
848 if (state == PM_SUSPEND_ON
849 && strcmp(buf, "off") && strcmp(buf, "off\n"))
850 return -EINVAL;
851
852 if (state == PM_SUSPEND_MEM)
853 state = mem_sleep_current;
854
855 error = pm_autosleep_set_state(state);
856 return error ? error : n;
857}
858
859power_attr(autosleep);
860#endif /* CONFIG_PM_AUTOSLEEP */
861
862#ifdef CONFIG_PM_WAKELOCKS
863static ssize_t wake_lock_show(struct kobject *kobj,
864 struct kobj_attribute *attr,
865 char *buf)
866{
867 return pm_show_wakelocks(buf, true);
868}
869
870static ssize_t wake_lock_store(struct kobject *kobj,
871 struct kobj_attribute *attr,
872 const char *buf, size_t n)
873{
874 int error = pm_wake_lock(buf);
875 return error ? error : n;
876}
877
878power_attr(wake_lock);
879
880static ssize_t wake_unlock_show(struct kobject *kobj,
881 struct kobj_attribute *attr,
882 char *buf)
883{
884 return pm_show_wakelocks(buf, false);
885}
886
887static ssize_t wake_unlock_store(struct kobject *kobj,
888 struct kobj_attribute *attr,
889 const char *buf, size_t n)
890{
891 int error = pm_wake_unlock(buf);
892 return error ? error : n;
893}
894
895power_attr(wake_unlock);
896
897#endif /* CONFIG_PM_WAKELOCKS */
898#endif /* CONFIG_PM_SLEEP */
899
900#ifdef CONFIG_PM_TRACE
901int pm_trace_enabled;
902
903static ssize_t pm_trace_show(struct kobject *kobj, struct kobj_attribute *attr,
904 char *buf)
905{
906 return sprintf(buf, "%d\n", pm_trace_enabled);
907}
908
909static ssize_t
910pm_trace_store(struct kobject *kobj, struct kobj_attribute *attr,
911 const char *buf, size_t n)
912{
913 int val;
914
915 if (sscanf(buf, "%d", &val) == 1) {
916 pm_trace_enabled = !!val;
917 if (pm_trace_enabled) {
918 pr_warn("PM: Enabling pm_trace changes system date and time during resume.\n"
919 "PM: Correct system time has to be restored manually after resume.\n");
920 }
921 return n;
922 }
923 return -EINVAL;
924}
925
926power_attr(pm_trace);
927
928static ssize_t pm_trace_dev_match_show(struct kobject *kobj,
929 struct kobj_attribute *attr,
930 char *buf)
931{
932 return show_trace_dev_match(buf, PAGE_SIZE);
933}
934
935power_attr_ro(pm_trace_dev_match);
936
937#endif /* CONFIG_PM_TRACE */
938
939#ifdef CONFIG_FREEZER
940static ssize_t pm_freeze_timeout_show(struct kobject *kobj,
941 struct kobj_attribute *attr, char *buf)
942{
943 return sprintf(buf, "%u\n", freeze_timeout_msecs);
944}
945
946static ssize_t pm_freeze_timeout_store(struct kobject *kobj,
947 struct kobj_attribute *attr,
948 const char *buf, size_t n)
949{
950 unsigned long val;
951
952 if (kstrtoul(buf, 10, &val))
953 return -EINVAL;
954
955 freeze_timeout_msecs = val;
956 return n;
957}
958
959power_attr(pm_freeze_timeout);
960
961#endif /* CONFIG_FREEZER*/
962
963static struct attribute * g[] = {
964 &state_attr.attr,
965#ifdef CONFIG_PM_TRACE
966 &pm_trace_attr.attr,
967 &pm_trace_dev_match_attr.attr,
968#endif
969#ifdef CONFIG_PM_SLEEP
970 &pm_async_attr.attr,
971 &wakeup_count_attr.attr,
972#ifdef CONFIG_SUSPEND
973 &mem_sleep_attr.attr,
974 &sync_on_suspend_attr.attr,
975#endif
976#ifdef CONFIG_PM_AUTOSLEEP
977 &autosleep_attr.attr,
978#endif
979#ifdef CONFIG_PM_WAKELOCKS
980 &wake_lock_attr.attr,
981 &wake_unlock_attr.attr,
982#endif
983#ifdef CONFIG_PM_SLEEP_DEBUG
984 &pm_test_attr.attr,
985 &pm_print_times_attr.attr,
986 &pm_wakeup_irq_attr.attr,
987 &pm_debug_messages_attr.attr,
988#endif
989#endif
990#ifdef CONFIG_FREEZER
991 &pm_freeze_timeout_attr.attr,
992#endif
993 NULL,
994};
995
996static const struct attribute_group attr_group = {
997 .attrs = g,
998};
999
1000static const struct attribute_group *attr_groups[] = {
1001 &attr_group,
1002#ifdef CONFIG_PM_SLEEP
1003 &suspend_attr_group,
1004#endif
1005 NULL,
1006};
1007
1008struct workqueue_struct *pm_wq;
1009EXPORT_SYMBOL_GPL(pm_wq);
1010
1011static int __init pm_start_workqueue(void)
1012{
1013 pm_wq = alloc_workqueue("pm", WQ_FREEZABLE, 0);
1014
1015 return pm_wq ? 0 : -ENOMEM;
1016}
1017
1018static int __init pm_init(void)
1019{
1020 int error = pm_start_workqueue();
1021 if (error)
1022 return error;
1023 hibernate_image_size_init();
1024 hibernate_reserved_size_init();
1025 pm_states_init();
1026 power_kobj = kobject_create_and_add("power", NULL);
1027 if (!power_kobj)
1028 return -ENOMEM;
1029 error = sysfs_create_groups(power_kobj, attr_groups);
1030 if (error)
1031 return error;
1032 pm_print_times_init();
1033 return pm_autosleep_init();
1034}
1035
1036core_initcall(pm_init);