diff options
Diffstat (limited to 'drivers/base/power/main.c')
| -rw-r--r-- | drivers/base/power/main.c | 344 |
1 files changed, 340 insertions, 4 deletions
diff --git a/drivers/base/power/main.c b/drivers/base/power/main.c index eb9f38d0aa58..0ab4ab21f564 100644 --- a/drivers/base/power/main.c +++ b/drivers/base/power/main.c | |||
| @@ -20,19 +20,24 @@ | |||
| 20 | */ | 20 | */ |
| 21 | 21 | ||
| 22 | #include <linux/device.h> | 22 | #include <linux/device.h> |
| 23 | #include <linux/kallsyms.h> | ||
| 23 | #include <linux/mutex.h> | 24 | #include <linux/mutex.h> |
| 25 | #include <linux/pm.h> | ||
| 26 | #include <linux/resume-trace.h> | ||
| 24 | 27 | ||
| 28 | #include "../base.h" | ||
| 25 | #include "power.h" | 29 | #include "power.h" |
| 26 | 30 | ||
| 27 | LIST_HEAD(dpm_active); | 31 | LIST_HEAD(dpm_active); |
| 28 | LIST_HEAD(dpm_off); | 32 | static LIST_HEAD(dpm_off); |
| 29 | LIST_HEAD(dpm_off_irq); | 33 | static LIST_HEAD(dpm_off_irq); |
| 30 | 34 | ||
| 31 | DEFINE_MUTEX(dpm_mtx); | 35 | static DEFINE_MUTEX(dpm_mtx); |
| 32 | DEFINE_MUTEX(dpm_list_mtx); | 36 | static DEFINE_MUTEX(dpm_list_mtx); |
| 33 | 37 | ||
| 34 | int (*platform_enable_wakeup)(struct device *dev, int is_on); | 38 | int (*platform_enable_wakeup)(struct device *dev, int is_on); |
| 35 | 39 | ||
| 40 | |||
| 36 | int device_pm_add(struct device *dev) | 41 | int device_pm_add(struct device *dev) |
| 37 | { | 42 | { |
| 38 | int error; | 43 | int error; |
| @@ -61,3 +66,334 @@ void device_pm_remove(struct device *dev) | |||
| 61 | } | 66 | } |
| 62 | 67 | ||
| 63 | 68 | ||
| 69 | /*------------------------- Resume routines -------------------------*/ | ||
| 70 | |||
| 71 | /** | ||
| 72 | * resume_device - Restore state for one device. | ||
| 73 | * @dev: Device. | ||
| 74 | * | ||
| 75 | */ | ||
| 76 | |||
| 77 | static int resume_device(struct device * dev) | ||
| 78 | { | ||
| 79 | int error = 0; | ||
| 80 | |||
| 81 | TRACE_DEVICE(dev); | ||
| 82 | TRACE_RESUME(0); | ||
| 83 | |||
| 84 | down(&dev->sem); | ||
| 85 | |||
| 86 | if (dev->bus && dev->bus->resume) { | ||
| 87 | dev_dbg(dev,"resuming\n"); | ||
| 88 | error = dev->bus->resume(dev); | ||
| 89 | } | ||
| 90 | |||
| 91 | if (!error && dev->type && dev->type->resume) { | ||
| 92 | dev_dbg(dev,"resuming\n"); | ||
| 93 | error = dev->type->resume(dev); | ||
| 94 | } | ||
| 95 | |||
| 96 | if (!error && dev->class && dev->class->resume) { | ||
| 97 | dev_dbg(dev,"class resume\n"); | ||
| 98 | error = dev->class->resume(dev); | ||
| 99 | } | ||
| 100 | |||
| 101 | up(&dev->sem); | ||
| 102 | |||
| 103 | TRACE_RESUME(error); | ||
| 104 | return error; | ||
| 105 | } | ||
| 106 | |||
| 107 | |||
| 108 | static int resume_device_early(struct device * dev) | ||
| 109 | { | ||
| 110 | int error = 0; | ||
| 111 | |||
| 112 | TRACE_DEVICE(dev); | ||
| 113 | TRACE_RESUME(0); | ||
| 114 | if (dev->bus && dev->bus->resume_early) { | ||
| 115 | dev_dbg(dev,"EARLY resume\n"); | ||
| 116 | error = dev->bus->resume_early(dev); | ||
| 117 | } | ||
| 118 | TRACE_RESUME(error); | ||
| 119 | return error; | ||
| 120 | } | ||
| 121 | |||
| 122 | /* | ||
| 123 | * Resume the devices that have either not gone through | ||
| 124 | * the late suspend, or that did go through it but also | ||
| 125 | * went through the early resume | ||
| 126 | */ | ||
| 127 | static void dpm_resume(void) | ||
| 128 | { | ||
| 129 | mutex_lock(&dpm_list_mtx); | ||
| 130 | while(!list_empty(&dpm_off)) { | ||
| 131 | struct list_head * entry = dpm_off.next; | ||
| 132 | struct device * dev = to_device(entry); | ||
| 133 | |||
| 134 | get_device(dev); | ||
| 135 | list_move_tail(entry, &dpm_active); | ||
| 136 | |||
| 137 | mutex_unlock(&dpm_list_mtx); | ||
| 138 | resume_device(dev); | ||
| 139 | mutex_lock(&dpm_list_mtx); | ||
| 140 | put_device(dev); | ||
| 141 | } | ||
| 142 | mutex_unlock(&dpm_list_mtx); | ||
| 143 | } | ||
| 144 | |||
| 145 | |||
| 146 | /** | ||
| 147 | * device_resume - Restore state of each device in system. | ||
| 148 | * | ||
| 149 | * Walk the dpm_off list, remove each entry, resume the device, | ||
| 150 | * then add it to the dpm_active list. | ||
| 151 | */ | ||
| 152 | |||
| 153 | void device_resume(void) | ||
| 154 | { | ||
| 155 | might_sleep(); | ||
| 156 | mutex_lock(&dpm_mtx); | ||
| 157 | dpm_resume(); | ||
| 158 | mutex_unlock(&dpm_mtx); | ||
| 159 | } | ||
| 160 | |||
| 161 | EXPORT_SYMBOL_GPL(device_resume); | ||
| 162 | |||
| 163 | |||
| 164 | /** | ||
| 165 | * dpm_power_up - Power on some devices. | ||
| 166 | * | ||
| 167 | * Walk the dpm_off_irq list and power each device up. This | ||
| 168 | * is used for devices that required they be powered down with | ||
| 169 | * interrupts disabled. As devices are powered on, they are moved | ||
| 170 | * to the dpm_active list. | ||
| 171 | * | ||
| 172 | * Interrupts must be disabled when calling this. | ||
| 173 | */ | ||
| 174 | |||
| 175 | static void dpm_power_up(void) | ||
| 176 | { | ||
| 177 | while(!list_empty(&dpm_off_irq)) { | ||
| 178 | struct list_head * entry = dpm_off_irq.next; | ||
| 179 | struct device * dev = to_device(entry); | ||
| 180 | |||
| 181 | list_move_tail(entry, &dpm_off); | ||
| 182 | resume_device_early(dev); | ||
| 183 | } | ||
| 184 | } | ||
| 185 | |||
| 186 | |||
| 187 | /** | ||
| 188 | * device_power_up - Turn on all devices that need special attention. | ||
| 189 | * | ||
| 190 | * Power on system devices then devices that required we shut them down | ||
| 191 | * with interrupts disabled. | ||
| 192 | * Called with interrupts disabled. | ||
| 193 | */ | ||
| 194 | |||
| 195 | void device_power_up(void) | ||
| 196 | { | ||
| 197 | sysdev_resume(); | ||
| 198 | dpm_power_up(); | ||
| 199 | } | ||
| 200 | |||
| 201 | EXPORT_SYMBOL_GPL(device_power_up); | ||
| 202 | |||
| 203 | |||
| 204 | /*------------------------- Suspend routines -------------------------*/ | ||
| 205 | |||
| 206 | /* | ||
| 207 | * The entries in the dpm_active list are in a depth first order, simply | ||
| 208 | * because children are guaranteed to be discovered after parents, and | ||
| 209 | * are inserted at the back of the list on discovery. | ||
| 210 | * | ||
| 211 | * All list on the suspend path are done in reverse order, so we operate | ||
| 212 | * on the leaves of the device tree (or forests, depending on how you want | ||
| 213 | * to look at it ;) first. As nodes are removed from the back of the list, | ||
| 214 | * they are inserted into the front of their destintation lists. | ||
| 215 | * | ||
| 216 | * Things are the reverse on the resume path - iterations are done in | ||
| 217 | * forward order, and nodes are inserted at the back of their destination | ||
| 218 | * lists. This way, the ancestors will be accessed before their descendents. | ||
| 219 | */ | ||
| 220 | |||
| 221 | static inline char *suspend_verb(u32 event) | ||
| 222 | { | ||
| 223 | switch (event) { | ||
| 224 | case PM_EVENT_SUSPEND: return "suspend"; | ||
| 225 | case PM_EVENT_FREEZE: return "freeze"; | ||
| 226 | case PM_EVENT_PRETHAW: return "prethaw"; | ||
| 227 | default: return "(unknown suspend event)"; | ||
| 228 | } | ||
| 229 | } | ||
| 230 | |||
| 231 | |||
| 232 | static void | ||
| 233 | suspend_device_dbg(struct device *dev, pm_message_t state, char *info) | ||
| 234 | { | ||
| 235 | dev_dbg(dev, "%s%s%s\n", info, suspend_verb(state.event), | ||
| 236 | ((state.event == PM_EVENT_SUSPEND) && device_may_wakeup(dev)) ? | ||
| 237 | ", may wakeup" : ""); | ||
| 238 | } | ||
| 239 | |||
| 240 | /** | ||
| 241 | * suspend_device - Save state of one device. | ||
| 242 | * @dev: Device. | ||
| 243 | * @state: Power state device is entering. | ||
| 244 | */ | ||
| 245 | |||
| 246 | static int suspend_device(struct device * dev, pm_message_t state) | ||
| 247 | { | ||
| 248 | int error = 0; | ||
| 249 | |||
| 250 | down(&dev->sem); | ||
| 251 | if (dev->power.power_state.event) { | ||
| 252 | dev_dbg(dev, "PM: suspend %d-->%d\n", | ||
| 253 | dev->power.power_state.event, state.event); | ||
| 254 | } | ||
| 255 | |||
| 256 | if (dev->class && dev->class->suspend) { | ||
| 257 | suspend_device_dbg(dev, state, "class "); | ||
| 258 | error = dev->class->suspend(dev, state); | ||
| 259 | suspend_report_result(dev->class->suspend, error); | ||
| 260 | } | ||
| 261 | |||
| 262 | if (!error && dev->type && dev->type->suspend) { | ||
| 263 | suspend_device_dbg(dev, state, "type "); | ||
| 264 | error = dev->type->suspend(dev, state); | ||
| 265 | suspend_report_result(dev->type->suspend, error); | ||
| 266 | } | ||
| 267 | |||
| 268 | if (!error && dev->bus && dev->bus->suspend) { | ||
| 269 | suspend_device_dbg(dev, state, ""); | ||
| 270 | error = dev->bus->suspend(dev, state); | ||
| 271 | suspend_report_result(dev->bus->suspend, error); | ||
| 272 | } | ||
| 273 | up(&dev->sem); | ||
| 274 | return error; | ||
| 275 | } | ||
| 276 | |||
| 277 | |||
| 278 | /* | ||
| 279 | * This is called with interrupts off, only a single CPU | ||
| 280 | * running. We can't acquire a mutex or semaphore (and we don't | ||
| 281 | * need the protection) | ||
| 282 | */ | ||
| 283 | static int suspend_device_late(struct device *dev, pm_message_t state) | ||
| 284 | { | ||
| 285 | int error = 0; | ||
| 286 | |||
| 287 | if (dev->bus && dev->bus->suspend_late) { | ||
| 288 | suspend_device_dbg(dev, state, "LATE "); | ||
| 289 | error = dev->bus->suspend_late(dev, state); | ||
| 290 | suspend_report_result(dev->bus->suspend_late, error); | ||
| 291 | } | ||
| 292 | return error; | ||
| 293 | } | ||
| 294 | |||
| 295 | /** | ||
| 296 | * device_suspend - Save state and stop all devices in system. | ||
| 297 | * @state: Power state to put each device in. | ||
| 298 | * | ||
| 299 | * Walk the dpm_active list, call ->suspend() for each device, and move | ||
| 300 | * it to the dpm_off list. | ||
| 301 | * | ||
| 302 | * (For historical reasons, if it returns -EAGAIN, that used to mean | ||
| 303 | * that the device would be called again with interrupts disabled. | ||
| 304 | * These days, we use the "suspend_late()" callback for that, so we | ||
| 305 | * print a warning and consider it an error). | ||
| 306 | * | ||
| 307 | * If we get a different error, try and back out. | ||
| 308 | * | ||
| 309 | * If we hit a failure with any of the devices, call device_resume() | ||
| 310 | * above to bring the suspended devices back to life. | ||
| 311 | * | ||
| 312 | */ | ||
| 313 | |||
| 314 | int device_suspend(pm_message_t state) | ||
| 315 | { | ||
| 316 | int error = 0; | ||
| 317 | |||
| 318 | might_sleep(); | ||
| 319 | mutex_lock(&dpm_mtx); | ||
| 320 | mutex_lock(&dpm_list_mtx); | ||
| 321 | while (!list_empty(&dpm_active) && error == 0) { | ||
| 322 | struct list_head * entry = dpm_active.prev; | ||
| 323 | struct device * dev = to_device(entry); | ||
| 324 | |||
| 325 | get_device(dev); | ||
| 326 | mutex_unlock(&dpm_list_mtx); | ||
| 327 | |||
| 328 | error = suspend_device(dev, state); | ||
| 329 | |||
| 330 | mutex_lock(&dpm_list_mtx); | ||
| 331 | |||
| 332 | /* Check if the device got removed */ | ||
| 333 | if (!list_empty(&dev->power.entry)) { | ||
| 334 | /* Move it to the dpm_off list */ | ||
| 335 | if (!error) | ||
| 336 | list_move(&dev->power.entry, &dpm_off); | ||
| 337 | } | ||
| 338 | if (error) | ||
| 339 | printk(KERN_ERR "Could not suspend device %s: " | ||
| 340 | "error %d%s\n", | ||
| 341 | kobject_name(&dev->kobj), error, | ||
| 342 | error == -EAGAIN ? " (please convert to suspend_late)" : ""); | ||
| 343 | put_device(dev); | ||
| 344 | } | ||
| 345 | mutex_unlock(&dpm_list_mtx); | ||
| 346 | if (error) | ||
| 347 | dpm_resume(); | ||
| 348 | |||
| 349 | mutex_unlock(&dpm_mtx); | ||
| 350 | return error; | ||
| 351 | } | ||
| 352 | |||
| 353 | EXPORT_SYMBOL_GPL(device_suspend); | ||
| 354 | |||
| 355 | /** | ||
| 356 | * device_power_down - Shut down special devices. | ||
| 357 | * @state: Power state to enter. | ||
| 358 | * | ||
| 359 | * Walk the dpm_off_irq list, calling ->power_down() for each device that | ||
| 360 | * couldn't power down the device with interrupts enabled. When we're | ||
| 361 | * done, power down system devices. | ||
| 362 | */ | ||
| 363 | |||
| 364 | int device_power_down(pm_message_t state) | ||
| 365 | { | ||
| 366 | int error = 0; | ||
| 367 | struct device * dev; | ||
| 368 | |||
| 369 | while (!list_empty(&dpm_off)) { | ||
| 370 | struct list_head * entry = dpm_off.prev; | ||
| 371 | |||
| 372 | dev = to_device(entry); | ||
| 373 | error = suspend_device_late(dev, state); | ||
| 374 | if (error) | ||
| 375 | goto Error; | ||
| 376 | list_move(&dev->power.entry, &dpm_off_irq); | ||
| 377 | } | ||
| 378 | |||
| 379 | error = sysdev_suspend(state); | ||
| 380 | Done: | ||
| 381 | return error; | ||
| 382 | Error: | ||
| 383 | printk(KERN_ERR "Could not power down device %s: " | ||
| 384 | "error %d\n", kobject_name(&dev->kobj), error); | ||
| 385 | dpm_power_up(); | ||
| 386 | goto Done; | ||
| 387 | } | ||
| 388 | |||
| 389 | EXPORT_SYMBOL_GPL(device_power_down); | ||
| 390 | |||
| 391 | void __suspend_report_result(const char *function, void *fn, int ret) | ||
| 392 | { | ||
| 393 | if (ret) { | ||
| 394 | printk(KERN_ERR "%s(): ", function); | ||
| 395 | print_fn_descriptor_symbol("%s() returns ", (unsigned long)fn); | ||
| 396 | printk("%d\n", ret); | ||
| 397 | } | ||
| 398 | } | ||
| 399 | EXPORT_SYMBOL_GPL(__suspend_report_result); | ||
