2 * pm.h - Power management interface
4 * Copyright (C) 2000 Andrew Henroid
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
24 #include <linux/list.h>
25 #include <asm/atomic.h>
26 #include <asm/errno.h>
29 * Power management requests... these are passed to pm_send_all() and friends.
31 * these functions are old and deprecated, see below.
33 typedef int __bitwise pm_request_t;
35 #define PM_SUSPEND ((__force pm_request_t) 1) /* enter D1-D3 */
36 #define PM_RESUME ((__force pm_request_t) 2) /* enter D0 */
40 * Device types... these are passed to pm_register
42 typedef int __bitwise pm_dev_t;
44 #define PM_UNKNOWN_DEV ((__force pm_dev_t) 0) /* generic */
45 #define PM_SYS_DEV ((__force pm_dev_t) 1) /* system device (fan, KB controller, ...) */
46 #define PM_PCI_DEV ((__force pm_dev_t) 2) /* PCI device */
47 #define PM_USB_DEV ((__force pm_dev_t) 3) /* USB device */
48 #define PM_SCSI_DEV ((__force pm_dev_t) 4) /* SCSI device */
49 #define PM_ISA_DEV ((__force pm_dev_t) 5) /* ISA device */
50 #define PM_MTD_DEV ((__force pm_dev_t) 6) /* Memory Technology Device */
53 * System device hardware ID (PnP) values
57 PM_SYS_UNKNOWN = 0x00000000, /* generic */
58 PM_SYS_KBC = 0x41d00303, /* keyboard controller */
59 PM_SYS_COM = 0x41d00500, /* serial port */
60 PM_SYS_IRDA = 0x41d00510, /* IRDA controller */
61 PM_SYS_FDC = 0x41d00700, /* floppy controller */
62 PM_SYS_VGA = 0x41d00900, /* VGA controller */
63 PM_SYS_PCMCIA = 0x41d00e00, /* PCMCIA controller */
69 #define PM_PCI_ID(dev) ((dev)->bus->number << 16 | (dev)->devfn)
72 * Request handler callback
76 typedef int (*pm_callback)(struct pm_dev *dev, pm_request_t rqst, void *data);
79 * Dynamic device information
90 unsigned long prev_state;
92 struct list_head entry;
95 /* Functions above this comment are list-based old-style power
96 * management. Please avoid using them. */
99 * Callbacks for platform drivers to implement.
101 extern void (*pm_idle)(void);
102 extern void (*pm_power_off)(void);
103 extern void (*pm_power_off_prepare)(void);
106 * Device power management
111 typedef struct pm_message {
116 * struct pm_ops - device PM callbacks
118 * Several driver power state transitions are externally visible, affecting
119 * the state of pending I/O queues and (for drivers that touch hardware)
120 * interrupts, wakeups, DMA, and other hardware state. There may also be
121 * internal transitions to various low power modes, which are transparent
122 * to the rest of the driver stack (such as a driver that's ON gating off
123 * clocks which are not in active use).
125 * The externally visible transitions are handled with the help of the following
126 * callbacks included in this structure:
128 * @prepare: Prepare the device for the upcoming transition, but do NOT change
129 * its hardware state. Prevent new children of the device from being
130 * registered after @prepare() returns (the driver's subsystem and
131 * generally the rest of the kernel is supposed to prevent new calls to the
132 * probe method from being made too once @prepare() has succeeded). If
133 * @prepare() detects a situation it cannot handle (e.g. registration of a
134 * child already in progress), it may return -EAGAIN, so that the PM core
135 * can execute it once again (e.g. after the new child has been registered)
136 * to recover from the race condition. This method is executed for all
137 * kinds of suspend transitions and is followed by one of the suspend
138 * callbacks: @suspend(), @freeze(), or @poweroff().
139 * The PM core executes @prepare() for all devices before starting to
140 * execute suspend callbacks for any of them, so drivers may assume all of
141 * the other devices to be present and functional while @prepare() is being
142 * executed. In particular, it is safe to make GFP_KERNEL memory
143 * allocations from within @prepare(). However, drivers may NOT assume
144 * anything about the availability of the user space at that time and it
145 * is not correct to request firmware from within @prepare() (it's too
146 * late to do that). [To work around this limitation, drivers may
147 * register suspend and hibernation notifiers that are executed before the
148 * freezing of tasks.]
150 * @complete: Undo the changes made by @prepare(). This method is executed for
151 * all kinds of resume transitions, following one of the resume callbacks:
152 * @resume(), @thaw(), @restore(). Also called if the state transition
153 * fails before the driver's suspend callback (@suspend(), @freeze(),
154 * @poweroff()) can be executed (e.g. if the suspend callback fails for one
155 * of the other devices that the PM core has unsuccessfully attempted to
157 * The PM core executes @complete() after it has executed the appropriate
158 * resume callback for all devices.
160 * @suspend: Executed before putting the system into a sleep state in which the
161 * contents of main memory are preserved. Quiesce the device, put it into
162 * a low power state appropriate for the upcoming system state (such as
163 * PCI_D3hot), and enable wakeup events as appropriate.
165 * @resume: Executed after waking the system up from a sleep state in which the
166 * contents of main memory were preserved. Put the device into the
167 * appropriate state, according to the information saved in memory by the
168 * preceding @suspend(). The driver starts working again, responding to
169 * hardware events and software requests. The hardware may have gone
170 * through a power-off reset, or it may have maintained state from the
171 * previous suspend() which the driver may rely on while resuming. On most
172 * platforms, there are no restrictions on availability of resources like
173 * clocks during @resume().
175 * @freeze: Hibernation-specific, executed before creating a hibernation image.
176 * Quiesce operations so that a consistent image can be created, but do NOT
177 * otherwise put the device into a low power device state and do NOT emit
178 * system wakeup events. Save in main memory the device settings to be
179 * used by @restore() during the subsequent resume from hibernation or by
180 * the subsequent @thaw(), if the creation of the image or the restoration
181 * of main memory contents from it fails.
183 * @thaw: Hibernation-specific, executed after creating a hibernation image OR
184 * if the creation of the image fails. Also executed after a failing
185 * attempt to restore the contents of main memory from such an image.
186 * Undo the changes made by the preceding @freeze(), so the device can be
187 * operated in the same way as immediately before the call to @freeze().
189 * @poweroff: Hibernation-specific, executed after saving a hibernation image.
190 * Quiesce the device, put it into a low power state appropriate for the
191 * upcoming system state (such as PCI_D3hot), and enable wakeup events as
194 * @restore: Hibernation-specific, executed after restoring the contents of main
195 * memory from a hibernation image. Driver starts working again,
196 * responding to hardware events and software requests. Drivers may NOT
197 * make ANY assumptions about the hardware state right prior to @restore().
198 * On most platforms, there are no restrictions on availability of
199 * resources like clocks during @restore().
201 * All of the above callbacks, except for @complete(), return error codes.
202 * However, the error codes returned by the resume operations, @resume(),
203 * @thaw(), and @restore(), do not cause the PM core to abort the resume
204 * transition during which they are returned. The error codes returned in
205 * that cases are only printed by the PM core to the system logs for debugging
206 * purposes. Still, it is recommended that drivers only return error codes
207 * from their resume methods in case of an unrecoverable failure (i.e. when the
208 * device being handled refuses to resume and becomes unusable) to allow us to
209 * modify the PM core in the future, so that it can avoid attempting to handle
210 * devices that failed to resume and their children.
212 * It is allowed to unregister devices while the above callbacks are being
213 * executed. However, it is not allowed to unregister a device from within any
214 * of its own callbacks.
218 int (*prepare)(struct device *dev);
219 void (*complete)(struct device *dev);
220 int (*suspend)(struct device *dev);
221 int (*resume)(struct device *dev);
222 int (*freeze)(struct device *dev);
223 int (*thaw)(struct device *dev);
224 int (*poweroff)(struct device *dev);
225 int (*restore)(struct device *dev);
229 * struct pm_ext_ops - extended device PM callbacks
231 * Some devices require certain operations related to suspend and hibernation
232 * to be carried out with interrupts disabled. Thus, 'struct pm_ext_ops' below
233 * is defined, adding callbacks to be executed with interrupts disabled to
236 * The following callbacks included in 'struct pm_ext_ops' are executed with
237 * the nonboot CPUs switched off and with interrupts disabled on the only
238 * functional CPU. They also are executed with the PM core list of devices
239 * locked, so they must NOT unregister any devices.
241 * @suspend_noirq: Complete the operations of ->suspend() by carrying out any
242 * actions required for suspending the device that need interrupts to be
245 * @resume_noirq: Prepare for the execution of ->resume() by carrying out any
246 * actions required for resuming the device that need interrupts to be
249 * @freeze_noirq: Complete the operations of ->freeze() by carrying out any
250 * actions required for freezing the device that need interrupts to be
253 * @thaw_noirq: Prepare for the execution of ->thaw() by carrying out any
254 * actions required for thawing the device that need interrupts to be
257 * @poweroff_noirq: Complete the operations of ->poweroff() by carrying out any
258 * actions required for handling the device that need interrupts to be
261 * @restore_noirq: Prepare for the execution of ->restore() by carrying out any
262 * actions required for restoring the operations of the device that need
263 * interrupts to be disabled
265 * All of the above callbacks return error codes, but the error codes returned
266 * by the resume operations, @resume_noirq(), @thaw_noirq(), and
267 * @restore_noirq(), do not cause the PM core to abort the resume transition
268 * during which they are returned. The error codes returned in that cases are
269 * only printed by the PM core to the system logs for debugging purposes.
270 * Still, as stated above, it is recommended that drivers only return error
271 * codes from their resume methods if the device being handled fails to resume
272 * and is not usable any more.
277 int (*suspend_noirq)(struct device *dev);
278 int (*resume_noirq)(struct device *dev);
279 int (*freeze_noirq)(struct device *dev);
280 int (*thaw_noirq)(struct device *dev);
281 int (*poweroff_noirq)(struct device *dev);
282 int (*restore_noirq)(struct device *dev);
288 * The following PM_EVENT_ messages are defined for the internal use of the PM
289 * core, in order to provide a mechanism allowing the high level suspend and
290 * hibernation code to convey the necessary information to the device PM core
295 * FREEZE System is going to hibernate, call ->prepare() and ->freeze()
298 * SUSPEND System is going to suspend, call ->prepare() and ->suspend()
301 * HIBERNATE Hibernation image has been saved, call ->prepare() and
302 * ->poweroff() for all devices.
304 * QUIESCE Contents of main memory are going to be restored from a (loaded)
305 * hibernation image, call ->prepare() and ->freeze() for all
308 * RESUME System is resuming, call ->resume() and ->complete() for all
311 * THAW Hibernation image has been created, call ->thaw() and
312 * ->complete() for all devices.
314 * RESTORE Contents of main memory have been restored from a hibernation
315 * image, call ->restore() and ->complete() for all devices.
317 * RECOVER Creation of a hibernation image or restoration of the main
318 * memory contents from a hibernation image has failed, call
319 * ->thaw() and ->complete() for all devices.
322 #define PM_EVENT_ON 0x0000
323 #define PM_EVENT_FREEZE 0x0001
324 #define PM_EVENT_SUSPEND 0x0002
325 #define PM_EVENT_HIBERNATE 0x0004
326 #define PM_EVENT_QUIESCE 0x0008
327 #define PM_EVENT_RESUME 0x0010
328 #define PM_EVENT_THAW 0x0020
329 #define PM_EVENT_RESTORE 0x0040
330 #define PM_EVENT_RECOVER 0x0080
332 #define PM_EVENT_SLEEP (PM_EVENT_SUSPEND | PM_EVENT_HIBERNATE)
334 #define PMSG_FREEZE ((struct pm_message){ .event = PM_EVENT_FREEZE, })
335 #define PMSG_QUIESCE ((struct pm_message){ .event = PM_EVENT_QUIESCE, })
336 #define PMSG_SUSPEND ((struct pm_message){ .event = PM_EVENT_SUSPEND, })
337 #define PMSG_HIBERNATE ((struct pm_message){ .event = PM_EVENT_HIBERNATE, })
338 #define PMSG_RESUME ((struct pm_message){ .event = PM_EVENT_RESUME, })
339 #define PMSG_THAW ((struct pm_message){ .event = PM_EVENT_THAW, })
340 #define PMSG_RESTORE ((struct pm_message){ .event = PM_EVENT_RESTORE, })
341 #define PMSG_RECOVER ((struct pm_message){ .event = PM_EVENT_RECOVER, })
342 #define PMSG_ON ((struct pm_message){ .event = PM_EVENT_ON, })
345 * Device power management states
347 * These state labels are used internally by the PM core to indicate the current
348 * status of a device with respect to the PM core operations.
350 * DPM_ON Device is regarded as operational. Set this way
351 * initially and when ->complete() is about to be called.
352 * Also set when ->prepare() fails.
354 * DPM_PREPARING Device is going to be prepared for a PM transition. Set
355 * when ->prepare() is about to be called.
357 * DPM_RESUMING Device is going to be resumed. Set when ->resume(),
358 * ->thaw(), or ->restore() is about to be called.
360 * DPM_SUSPENDING Device has been prepared for a power transition. Set
361 * when ->prepare() has just succeeded.
363 * DPM_OFF Device is regarded as inactive. Set immediately after
364 * ->suspend(), ->freeze(), or ->poweroff() has succeeded.
365 * Also set when ->resume()_noirq, ->thaw_noirq(), or
366 * ->restore_noirq() is about to be called.
368 * DPM_OFF_IRQ Device is in a "deep sleep". Set immediately after
369 * ->suspend_noirq(), ->freeze_noirq(), or
370 * ->poweroff_noirq() has just succeeded.
384 pm_message_t power_state;
385 unsigned can_wakeup:1;
386 unsigned should_wakeup:1;
387 enum dpm_state status; /* Owned by the PM core */
388 #ifdef CONFIG_PM_SLEEP
389 struct list_head entry;
394 * The PM_EVENT_ messages are also used by drivers implementing the legacy
395 * suspend framework, based on the ->suspend() and ->resume() callbacks common
396 * for suspend and hibernation transitions, according to the rules below.
399 /* Necessary, because several drivers use PM_EVENT_PRETHAW */
400 #define PM_EVENT_PRETHAW PM_EVENT_QUIESCE
403 * One transition is triggered by resume(), after a suspend() call; the
404 * message is implicit:
406 * ON Driver starts working again, responding to hardware events
407 * and software requests. The hardware may have gone through
408 * a power-off reset, or it may have maintained state from the
409 * previous suspend() which the driver will rely on while
410 * resuming. On most platforms, there are no restrictions on
411 * availability of resources like clocks during resume().
413 * Other transitions are triggered by messages sent using suspend(). All
414 * these transitions quiesce the driver, so that I/O queues are inactive.
415 * That commonly entails turning off IRQs and DMA; there may be rules
416 * about how to quiesce that are specific to the bus or the device's type.
417 * (For example, network drivers mark the link state.) Other details may
418 * differ according to the message:
420 * SUSPEND Quiesce, enter a low power device state appropriate for
421 * the upcoming system state (such as PCI_D3hot), and enable
422 * wakeup events as appropriate.
424 * HIBERNATE Enter a low power device state appropriate for the hibernation
425 * state (eg. ACPI S4) and enable wakeup events as appropriate.
427 * FREEZE Quiesce operations so that a consistent image can be saved;
428 * but do NOT otherwise enter a low power device state, and do
429 * NOT emit system wakeup events.
431 * PRETHAW Quiesce as if for FREEZE; additionally, prepare for restoring
432 * the system from a snapshot taken after an earlier FREEZE.
433 * Some drivers will need to reset their hardware state instead
434 * of preserving it, to ensure that it's never mistaken for the
435 * state which that earlier snapshot had set up.
437 * A minimally power-aware driver treats all messages as SUSPEND, fully
438 * reinitializes its device during resume() -- whether or not it was reset
439 * during the suspend/resume cycle -- and can't issue wakeup events.
441 * More power-aware drivers may also use low power states at runtime as
442 * well as during system sleep states like PM_SUSPEND_STANDBY. They may
443 * be able to use wakeup events to exit from runtime low-power states,
444 * or from system low-power states such as standby or suspend-to-RAM.
447 #ifdef CONFIG_PM_SLEEP
448 extern void device_pm_lock(void);
449 extern void device_power_up(pm_message_t state);
450 extern void device_resume(pm_message_t state);
452 extern void device_pm_unlock(void);
453 extern int device_power_down(pm_message_t state);
454 extern int device_suspend(pm_message_t state);
455 extern int device_prepare_suspend(pm_message_t state);
457 extern void __suspend_report_result(const char *function, void *fn, int ret);
459 #define suspend_report_result(fn, ret) \
461 __suspend_report_result(__FUNCTION__, fn, ret); \
464 #else /* !CONFIG_PM_SLEEP */
466 static inline int device_suspend(pm_message_t state)
471 #define suspend_report_result(fn, ret) do {} while (0)
473 #endif /* !CONFIG_PM_SLEEP */
476 * Global Power Management flags
477 * Used to keep APM and ACPI from both being active
479 extern unsigned int pm_flags;
484 #endif /* _LINUX_PM_H */