Rafael J. Wysocki | a9d7052 | 2009-06-10 01:27:12 +0200 | [diff] [blame] | 1 | /* |
| 2 | * kernel/power/suspend.c - Suspend to RAM and standby functionality. |
| 3 | * |
| 4 | * Copyright (c) 2003 Patrick Mochel |
| 5 | * Copyright (c) 2003 Open Source Development Lab |
| 6 | * Copyright (c) 2009 Rafael J. Wysocki <rjw@sisk.pl>, Novell Inc. |
| 7 | * |
| 8 | * This file is released under the GPLv2. |
| 9 | */ |
| 10 | |
| 11 | #include <linux/string.h> |
| 12 | #include <linux/delay.h> |
| 13 | #include <linux/errno.h> |
| 14 | #include <linux/init.h> |
| 15 | #include <linux/console.h> |
| 16 | #include <linux/cpu.h> |
| 17 | #include <linux/syscalls.h> |
Tejun Heo | 5a0e3ad | 2010-03-24 17:04:11 +0900 | [diff] [blame] | 18 | #include <linux/gfp.h> |
Matthew Garrett | dd4c4f1 | 2010-05-28 16:32:14 -0400 | [diff] [blame] | 19 | #include <linux/io.h> |
| 20 | #include <linux/kernel.h> |
| 21 | #include <linux/list.h> |
| 22 | #include <linux/mm.h> |
| 23 | #include <linux/slab.h> |
| 24 | #include <linux/suspend.h> |
Rafael J. Wysocki | 40dc166 | 2011-03-15 00:43:46 +0100 | [diff] [blame] | 25 | #include <linux/syscore_ops.h> |
Jean Pihet | 938cfed | 2011-01-05 19:49:01 +0100 | [diff] [blame] | 26 | #include <trace/events/power.h> |
Rafael J. Wysocki | a9d7052 | 2009-06-10 01:27:12 +0200 | [diff] [blame] | 27 | |
| 28 | #include "power.h" |
| 29 | |
| 30 | const char *const pm_states[PM_SUSPEND_MAX] = { |
| 31 | [PM_SUSPEND_STANDBY] = "standby", |
| 32 | [PM_SUSPEND_MEM] = "mem", |
| 33 | }; |
| 34 | |
Lionel Debroux | 2f55ac0 | 2010-11-16 14:14:02 +0100 | [diff] [blame] | 35 | static const struct platform_suspend_ops *suspend_ops; |
Rafael J. Wysocki | a9d7052 | 2009-06-10 01:27:12 +0200 | [diff] [blame] | 36 | |
| 37 | /** |
| 38 | * suspend_set_ops - Set the global suspend method table. |
| 39 | * @ops: Pointer to ops structure. |
| 40 | */ |
Lionel Debroux | 2f55ac0 | 2010-11-16 14:14:02 +0100 | [diff] [blame] | 41 | void suspend_set_ops(const struct platform_suspend_ops *ops) |
Rafael J. Wysocki | a9d7052 | 2009-06-10 01:27:12 +0200 | [diff] [blame] | 42 | { |
| 43 | mutex_lock(&pm_mutex); |
| 44 | suspend_ops = ops; |
| 45 | mutex_unlock(&pm_mutex); |
| 46 | } |
Kevin Hilman | a5e4fd8 | 2011-06-27 01:01:07 +0200 | [diff] [blame] | 47 | EXPORT_SYMBOL_GPL(suspend_set_ops); |
Rafael J. Wysocki | a9d7052 | 2009-06-10 01:27:12 +0200 | [diff] [blame] | 48 | |
| 49 | bool valid_state(suspend_state_t state) |
| 50 | { |
| 51 | /* |
| 52 | * All states need lowlevel support and need to be valid to the lowlevel |
| 53 | * implementation, no valid callback implies that none are valid. |
| 54 | */ |
| 55 | return suspend_ops && suspend_ops->valid && suspend_ops->valid(state); |
| 56 | } |
| 57 | |
| 58 | /** |
| 59 | * suspend_valid_only_mem - generic memory-only valid callback |
| 60 | * |
| 61 | * Platform drivers that implement mem suspend only and only need |
| 62 | * to check for that in their .valid callback can use this instead |
| 63 | * of rolling their own .valid callback. |
| 64 | */ |
| 65 | int suspend_valid_only_mem(suspend_state_t state) |
| 66 | { |
| 67 | return state == PM_SUSPEND_MEM; |
| 68 | } |
Kevin Hilman | a5e4fd8 | 2011-06-27 01:01:07 +0200 | [diff] [blame] | 69 | EXPORT_SYMBOL_GPL(suspend_valid_only_mem); |
Rafael J. Wysocki | a9d7052 | 2009-06-10 01:27:12 +0200 | [diff] [blame] | 70 | |
| 71 | static int suspend_test(int level) |
| 72 | { |
| 73 | #ifdef CONFIG_PM_DEBUG |
| 74 | if (pm_test_level == level) { |
| 75 | printk(KERN_INFO "suspend debug: Waiting for 5 seconds.\n"); |
| 76 | mdelay(5000); |
| 77 | return 1; |
| 78 | } |
| 79 | #endif /* !CONFIG_PM_DEBUG */ |
| 80 | return 0; |
| 81 | } |
| 82 | |
| 83 | /** |
| 84 | * suspend_prepare - Do prep work before entering low-power state. |
| 85 | * |
| 86 | * This is common code that is called for each state that we're entering. |
| 87 | * Run suspend notifiers, allocate a console and stop all processes. |
| 88 | */ |
| 89 | static int suspend_prepare(void) |
| 90 | { |
| 91 | int error; |
| 92 | |
| 93 | if (!suspend_ops || !suspend_ops->enter) |
| 94 | return -EPERM; |
| 95 | |
| 96 | pm_prepare_console(); |
| 97 | |
| 98 | error = pm_notifier_call_chain(PM_SUSPEND_PREPARE); |
| 99 | if (error) |
| 100 | goto Finish; |
| 101 | |
| 102 | error = usermodehelper_disable(); |
| 103 | if (error) |
| 104 | goto Finish; |
| 105 | |
| 106 | error = suspend_freeze_processes(); |
| 107 | if (!error) |
| 108 | return 0; |
| 109 | |
| 110 | suspend_thaw_processes(); |
| 111 | usermodehelper_enable(); |
| 112 | Finish: |
| 113 | pm_notifier_call_chain(PM_POST_SUSPEND); |
| 114 | pm_restore_console(); |
| 115 | return error; |
| 116 | } |
| 117 | |
| 118 | /* default implementation */ |
| 119 | void __attribute__ ((weak)) arch_suspend_disable_irqs(void) |
| 120 | { |
| 121 | local_irq_disable(); |
| 122 | } |
| 123 | |
| 124 | /* default implementation */ |
| 125 | void __attribute__ ((weak)) arch_suspend_enable_irqs(void) |
| 126 | { |
| 127 | local_irq_enable(); |
| 128 | } |
| 129 | |
| 130 | /** |
MyungJoo Ham | 3b5fe85 | 2011-06-12 15:57:05 +0200 | [diff] [blame] | 131 | * suspend_enter - enter the desired system sleep state. |
| 132 | * @state: State to enter |
| 133 | * @wakeup: Returns information that suspend should not be entered again. |
Rafael J. Wysocki | a9d7052 | 2009-06-10 01:27:12 +0200 | [diff] [blame] | 134 | * |
MyungJoo Ham | 3b5fe85 | 2011-06-12 15:57:05 +0200 | [diff] [blame] | 135 | * This function should be called after devices have been suspended. |
Rafael J. Wysocki | a9d7052 | 2009-06-10 01:27:12 +0200 | [diff] [blame] | 136 | */ |
MyungJoo Ham | 3b5fe85 | 2011-06-12 15:57:05 +0200 | [diff] [blame] | 137 | static int suspend_enter(suspend_state_t state, bool *wakeup) |
Rafael J. Wysocki | a9d7052 | 2009-06-10 01:27:12 +0200 | [diff] [blame] | 138 | { |
| 139 | int error; |
| 140 | |
| 141 | if (suspend_ops->prepare) { |
| 142 | error = suspend_ops->prepare(); |
| 143 | if (error) |
Rafael J. Wysocki | ce44101 | 2010-07-07 23:43:45 +0200 | [diff] [blame] | 144 | goto Platform_finish; |
Rafael J. Wysocki | a9d7052 | 2009-06-10 01:27:12 +0200 | [diff] [blame] | 145 | } |
| 146 | |
| 147 | error = dpm_suspend_noirq(PMSG_SUSPEND); |
| 148 | if (error) { |
| 149 | printk(KERN_ERR "PM: Some devices failed to power down\n"); |
Rafael J. Wysocki | ce44101 | 2010-07-07 23:43:45 +0200 | [diff] [blame] | 150 | goto Platform_finish; |
Rafael J. Wysocki | a9d7052 | 2009-06-10 01:27:12 +0200 | [diff] [blame] | 151 | } |
| 152 | |
| 153 | if (suspend_ops->prepare_late) { |
| 154 | error = suspend_ops->prepare_late(); |
| 155 | if (error) |
Rafael J. Wysocki | ce44101 | 2010-07-07 23:43:45 +0200 | [diff] [blame] | 156 | goto Platform_wake; |
Rafael J. Wysocki | a9d7052 | 2009-06-10 01:27:12 +0200 | [diff] [blame] | 157 | } |
| 158 | |
| 159 | if (suspend_test(TEST_PLATFORM)) |
| 160 | goto Platform_wake; |
| 161 | |
| 162 | error = disable_nonboot_cpus(); |
| 163 | if (error || suspend_test(TEST_CPUS)) |
| 164 | goto Enable_cpus; |
| 165 | |
| 166 | arch_suspend_disable_irqs(); |
| 167 | BUG_ON(!irqs_disabled()); |
| 168 | |
Rafael J. Wysocki | 2e711c0 | 2011-04-26 19:15:07 +0200 | [diff] [blame] | 169 | error = syscore_suspend(); |
Rafael J. Wysocki | a9d7052 | 2009-06-10 01:27:12 +0200 | [diff] [blame] | 170 | if (!error) { |
MyungJoo Ham | 3b5fe85 | 2011-06-12 15:57:05 +0200 | [diff] [blame] | 171 | *wakeup = pm_wakeup_pending(); |
| 172 | if (!(suspend_test(TEST_CORE) || *wakeup)) { |
Rafael J. Wysocki | a9d7052 | 2009-06-10 01:27:12 +0200 | [diff] [blame] | 173 | error = suspend_ops->enter(state); |
Rafael J. Wysocki | c125e96 | 2010-07-05 22:43:53 +0200 | [diff] [blame] | 174 | events_check_enabled = false; |
| 175 | } |
Rafael J. Wysocki | 40dc166 | 2011-03-15 00:43:46 +0100 | [diff] [blame] | 176 | syscore_resume(); |
Rafael J. Wysocki | a9d7052 | 2009-06-10 01:27:12 +0200 | [diff] [blame] | 177 | } |
| 178 | |
| 179 | arch_suspend_enable_irqs(); |
| 180 | BUG_ON(irqs_disabled()); |
| 181 | |
| 182 | Enable_cpus: |
| 183 | enable_nonboot_cpus(); |
| 184 | |
| 185 | Platform_wake: |
| 186 | if (suspend_ops->wake) |
| 187 | suspend_ops->wake(); |
| 188 | |
Rafael J. Wysocki | a9d7052 | 2009-06-10 01:27:12 +0200 | [diff] [blame] | 189 | dpm_resume_noirq(PMSG_RESUME); |
| 190 | |
Rafael J. Wysocki | ce44101 | 2010-07-07 23:43:45 +0200 | [diff] [blame] | 191 | Platform_finish: |
Rafael J. Wysocki | a9d7052 | 2009-06-10 01:27:12 +0200 | [diff] [blame] | 192 | if (suspend_ops->finish) |
| 193 | suspend_ops->finish(); |
| 194 | |
| 195 | return error; |
| 196 | } |
| 197 | |
| 198 | /** |
| 199 | * suspend_devices_and_enter - suspend devices and enter the desired system |
| 200 | * sleep state. |
| 201 | * @state: state to enter |
| 202 | */ |
| 203 | int suspend_devices_and_enter(suspend_state_t state) |
| 204 | { |
| 205 | int error; |
MyungJoo Ham | 3b5fe85 | 2011-06-12 15:57:05 +0200 | [diff] [blame] | 206 | bool wakeup = false; |
Rafael J. Wysocki | a9d7052 | 2009-06-10 01:27:12 +0200 | [diff] [blame] | 207 | |
| 208 | if (!suspend_ops) |
| 209 | return -ENOSYS; |
| 210 | |
Jean Pihet | 938cfed | 2011-01-05 19:49:01 +0100 | [diff] [blame] | 211 | trace_machine_suspend(state); |
Rafael J. Wysocki | a9d7052 | 2009-06-10 01:27:12 +0200 | [diff] [blame] | 212 | if (suspend_ops->begin) { |
| 213 | error = suspend_ops->begin(state); |
| 214 | if (error) |
| 215 | goto Close; |
| 216 | } |
| 217 | suspend_console(); |
| 218 | suspend_test_start(); |
| 219 | error = dpm_suspend_start(PMSG_SUSPEND); |
| 220 | if (error) { |
| 221 | printk(KERN_ERR "PM: Some devices failed to suspend\n"); |
| 222 | goto Recover_platform; |
| 223 | } |
| 224 | suspend_test_finish("suspend devices"); |
| 225 | if (suspend_test(TEST_DEVICES)) |
| 226 | goto Recover_platform; |
| 227 | |
MyungJoo Ham | 3b5fe85 | 2011-06-12 15:57:05 +0200 | [diff] [blame] | 228 | do { |
| 229 | error = suspend_enter(state, &wakeup); |
| 230 | } while (!error && !wakeup |
| 231 | && suspend_ops->suspend_again && suspend_ops->suspend_again()); |
Rafael J. Wysocki | a9d7052 | 2009-06-10 01:27:12 +0200 | [diff] [blame] | 232 | |
| 233 | Resume_devices: |
| 234 | suspend_test_start(); |
| 235 | dpm_resume_end(PMSG_RESUME); |
| 236 | suspend_test_finish("resume devices"); |
Rafael J. Wysocki | a9d7052 | 2009-06-10 01:27:12 +0200 | [diff] [blame] | 237 | resume_console(); |
| 238 | Close: |
| 239 | if (suspend_ops->end) |
| 240 | suspend_ops->end(); |
Jean Pihet | 938cfed | 2011-01-05 19:49:01 +0100 | [diff] [blame] | 241 | trace_machine_suspend(PWR_EVENT_EXIT); |
Rafael J. Wysocki | a9d7052 | 2009-06-10 01:27:12 +0200 | [diff] [blame] | 242 | return error; |
| 243 | |
| 244 | Recover_platform: |
| 245 | if (suspend_ops->recover) |
| 246 | suspend_ops->recover(); |
| 247 | goto Resume_devices; |
| 248 | } |
| 249 | |
| 250 | /** |
| 251 | * suspend_finish - Do final work before exiting suspend sequence. |
| 252 | * |
| 253 | * Call platform code to clean up, restart processes, and free the |
| 254 | * console that we've allocated. This is not called for suspend-to-disk. |
| 255 | */ |
| 256 | static void suspend_finish(void) |
| 257 | { |
| 258 | suspend_thaw_processes(); |
| 259 | usermodehelper_enable(); |
| 260 | pm_notifier_call_chain(PM_POST_SUSPEND); |
| 261 | pm_restore_console(); |
| 262 | } |
| 263 | |
| 264 | /** |
| 265 | * enter_state - Do common work of entering low-power state. |
| 266 | * @state: pm_state structure for state we're entering. |
| 267 | * |
| 268 | * Make sure we're the only ones trying to enter a sleep state. Fail |
| 269 | * if someone has beat us to it, since we don't want anything weird to |
| 270 | * happen when we wake up. |
| 271 | * Then, do the setup for suspend, enter the state, and cleaup (after |
| 272 | * we've woken up). |
| 273 | */ |
| 274 | int enter_state(suspend_state_t state) |
| 275 | { |
| 276 | int error; |
| 277 | |
| 278 | if (!valid_state(state)) |
| 279 | return -ENODEV; |
| 280 | |
| 281 | if (!mutex_trylock(&pm_mutex)) |
| 282 | return -EBUSY; |
| 283 | |
| 284 | printk(KERN_INFO "PM: Syncing filesystems ... "); |
| 285 | sys_sync(); |
| 286 | printk("done.\n"); |
| 287 | |
| 288 | pr_debug("PM: Preparing system for %s sleep\n", pm_states[state]); |
| 289 | error = suspend_prepare(); |
| 290 | if (error) |
| 291 | goto Unlock; |
| 292 | |
| 293 | if (suspend_test(TEST_FREEZER)) |
| 294 | goto Finish; |
| 295 | |
| 296 | pr_debug("PM: Entering %s sleep\n", pm_states[state]); |
Rafael J. Wysocki | 8718647 | 2011-05-10 21:09:53 +0200 | [diff] [blame] | 297 | pm_restrict_gfp_mask(); |
Rafael J. Wysocki | a9d7052 | 2009-06-10 01:27:12 +0200 | [diff] [blame] | 298 | error = suspend_devices_and_enter(state); |
Rafael J. Wysocki | 8718647 | 2011-05-10 21:09:53 +0200 | [diff] [blame] | 299 | pm_restore_gfp_mask(); |
Rafael J. Wysocki | a9d7052 | 2009-06-10 01:27:12 +0200 | [diff] [blame] | 300 | |
| 301 | Finish: |
| 302 | pr_debug("PM: Finishing wakeup.\n"); |
| 303 | suspend_finish(); |
| 304 | Unlock: |
| 305 | mutex_unlock(&pm_mutex); |
| 306 | return error; |
| 307 | } |
| 308 | |
| 309 | /** |
| 310 | * pm_suspend - Externally visible function for suspending system. |
| 311 | * @state: Enumerated value of state to enter. |
| 312 | * |
| 313 | * Determine whether or not value is within range, get state |
| 314 | * structure, and enter (above). |
| 315 | */ |
| 316 | int pm_suspend(suspend_state_t state) |
| 317 | { |
| 318 | if (state > PM_SUSPEND_ON && state <= PM_SUSPEND_MAX) |
| 319 | return enter_state(state); |
| 320 | return -EINVAL; |
| 321 | } |
| 322 | EXPORT_SYMBOL(pm_suspend); |