xref: /linux-6.15/include/linux/pm.h (revision eb2bce7f)
1 /*
2  *  pm.h - Power management interface
3  *
4  *  Copyright (C) 2000 Andrew Henroid
5  *
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.
10  *
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.
15  *
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
19  */
20 
21 #ifndef _LINUX_PM_H
22 #define _LINUX_PM_H
23 
24 #ifdef __KERNEL__
25 
26 #include <linux/list.h>
27 #include <asm/atomic.h>
28 
29 /*
30  * Power management requests... these are passed to pm_send_all() and friends.
31  *
32  * these functions are old and deprecated, see below.
33  */
34 typedef int __bitwise pm_request_t;
35 
36 #define PM_SUSPEND	((__force pm_request_t) 1)	/* enter D1-D3 */
37 #define PM_RESUME	((__force pm_request_t) 2)	/* enter D0 */
38 
39 
40 /*
41  * Device types... these are passed to pm_register
42  */
43 typedef int __bitwise pm_dev_t;
44 
45 #define PM_UNKNOWN_DEV	((__force pm_dev_t) 0)	/* generic */
46 #define PM_SYS_DEV	((__force pm_dev_t) 1)	/* system device (fan, KB controller, ...) */
47 #define PM_PCI_DEV	((__force pm_dev_t) 2)	/* PCI device */
48 #define PM_USB_DEV	((__force pm_dev_t) 3)	/* USB device */
49 #define PM_SCSI_DEV	((__force pm_dev_t) 4)	/* SCSI device */
50 #define PM_ISA_DEV	((__force pm_dev_t) 5)	/* ISA device */
51 #define	PM_MTD_DEV	((__force pm_dev_t) 6)	/* Memory Technology Device */
52 
53 /*
54  * System device hardware ID (PnP) values
55  */
56 enum
57 {
58 	PM_SYS_UNKNOWN = 0x00000000, /* generic */
59 	PM_SYS_KBC =	 0x41d00303, /* keyboard controller */
60 	PM_SYS_COM =	 0x41d00500, /* serial port */
61 	PM_SYS_IRDA =	 0x41d00510, /* IRDA controller */
62 	PM_SYS_FDC =	 0x41d00700, /* floppy controller */
63 	PM_SYS_VGA =	 0x41d00900, /* VGA controller */
64 	PM_SYS_PCMCIA =	 0x41d00e00, /* PCMCIA controller */
65 };
66 
67 /*
68  * Device identifier
69  */
70 #define PM_PCI_ID(dev) ((dev)->bus->number << 16 | (dev)->devfn)
71 
72 /*
73  * Request handler callback
74  */
75 struct pm_dev;
76 
77 typedef int (*pm_callback)(struct pm_dev *dev, pm_request_t rqst, void *data);
78 
79 /*
80  * Dynamic device information
81  */
82 struct pm_dev
83 {
84 	pm_dev_t	 type;
85 	unsigned long	 id;
86 	pm_callback	 callback;
87 	void		*data;
88 
89 	unsigned long	 flags;
90 	unsigned long	 state;
91 	unsigned long	 prev_state;
92 
93 	struct list_head entry;
94 };
95 
96 /* Functions above this comment are list-based old-style power
97  * managment. Please avoid using them.  */
98 
99 /*
100  * Callbacks for platform drivers to implement.
101  */
102 extern void (*pm_idle)(void);
103 extern void (*pm_power_off)(void);
104 
105 typedef int __bitwise suspend_state_t;
106 
107 #define PM_SUSPEND_ON		((__force suspend_state_t) 0)
108 #define PM_SUSPEND_STANDBY	((__force suspend_state_t) 1)
109 #define PM_SUSPEND_MEM		((__force suspend_state_t) 3)
110 #define PM_SUSPEND_DISK		((__force suspend_state_t) 4)
111 #define PM_SUSPEND_MAX		((__force suspend_state_t) 5)
112 
113 typedef int __bitwise suspend_disk_method_t;
114 
115 /* invalid must be 0 so struct pm_ops initialisers can leave it out */
116 #define PM_DISK_INVALID		((__force suspend_disk_method_t) 0)
117 #define	PM_DISK_PLATFORM	((__force suspend_disk_method_t) 1)
118 #define	PM_DISK_SHUTDOWN	((__force suspend_disk_method_t) 2)
119 #define	PM_DISK_REBOOT		((__force suspend_disk_method_t) 3)
120 #define	PM_DISK_TEST		((__force suspend_disk_method_t) 4)
121 #define	PM_DISK_TESTPROC	((__force suspend_disk_method_t) 5)
122 #define	PM_DISK_MAX		((__force suspend_disk_method_t) 6)
123 
124 /**
125  * struct pm_ops - Callbacks for managing platform dependent suspend states.
126  * @valid: Callback to determine whether the given state can be entered.
127  * 	If %CONFIG_SOFTWARE_SUSPEND is set then %PM_SUSPEND_DISK is
128  *	always valid and never passed to this call. If not assigned,
129  *	no suspend states are valid.
130  *	Valid states are advertised in /sys/power/state but can still
131  *	be rejected by prepare or enter if the conditions aren't right.
132  *	There is a %pm_valid_only_mem function available that can be assigned
133  *	to this if you only implement mem sleep.
134  *
135  * @prepare: Prepare the platform for the given suspend state. Can return a
136  *	negative error code if necessary.
137  *
138  * @enter: Enter the given suspend state, must be assigned. Can return a
139  *	negative error code if necessary.
140  *
141  * @finish: Called when the system has left the given state and all devices
142  *	are resumed. The return value is ignored.
143  *
144  * @pm_disk_mode: The generic code always allows one of the shutdown methods
145  *	%PM_DISK_SHUTDOWN, %PM_DISK_REBOOT, %PM_DISK_TEST and
146  *	%PM_DISK_TESTPROC. If this variable is set, the mode it is set
147  *	to is allowed in addition to those modes and is also made default.
148  *	When this mode is sent selected, the @prepare call will be called
149  *	before suspending to disk (if present), the @enter call should be
150  *	present and will be called after all state has been saved and the
151  *	machine is ready to be powered off; the @finish callback is called
152  *	after state has been restored. All these calls are called with
153  *	%PM_SUSPEND_DISK as the state.
154  */
155 struct pm_ops {
156 	int (*valid)(suspend_state_t state);
157 	int (*prepare)(suspend_state_t state);
158 	int (*enter)(suspend_state_t state);
159 	int (*finish)(suspend_state_t state);
160 	suspend_disk_method_t pm_disk_mode;
161 };
162 
163 /**
164  * pm_set_ops - set platform dependent power management ops
165  * @pm_ops: The new power management operations to set.
166  */
167 extern void pm_set_ops(struct pm_ops *pm_ops);
168 extern struct pm_ops *pm_ops;
169 extern int pm_suspend(suspend_state_t state);
170 
171 extern int pm_valid_only_mem(suspend_state_t state);
172 
173 /**
174  * arch_suspend_disable_irqs - disable IRQs for suspend
175  *
176  * Disables IRQs (in the default case). This is a weak symbol in the common
177  * code and thus allows architectures to override it if more needs to be
178  * done. Not called for suspend to disk.
179  */
180 extern void arch_suspend_disable_irqs(void);
181 
182 /**
183  * arch_suspend_enable_irqs - enable IRQs after suspend
184  *
185  * Enables IRQs (in the default case). This is a weak symbol in the common
186  * code and thus allows architectures to override it if more needs to be
187  * done. Not called for suspend to disk.
188  */
189 extern void arch_suspend_enable_irqs(void);
190 
191 /*
192  * Device power management
193  */
194 
195 struct device;
196 
197 typedef struct pm_message {
198 	int event;
199 } pm_message_t;
200 
201 /*
202  * Several driver power state transitions are externally visible, affecting
203  * the state of pending I/O queues and (for drivers that touch hardware)
204  * interrupts, wakeups, DMA, and other hardware state.  There may also be
205  * internal transitions to various low power modes, which are transparent
206  * to the rest of the driver stack (such as a driver that's ON gating off
207  * clocks which are not in active use).
208  *
209  * One transition is triggered by resume(), after a suspend() call; the
210  * message is implicit:
211  *
212  * ON		Driver starts working again, responding to hardware events
213  * 		and software requests.  The hardware may have gone through
214  * 		a power-off reset, or it may have maintained state from the
215  * 		previous suspend() which the driver will rely on while
216  * 		resuming.  On most platforms, there are no restrictions on
217  * 		availability of resources like clocks during resume().
218  *
219  * Other transitions are triggered by messages sent using suspend().  All
220  * these transitions quiesce the driver, so that I/O queues are inactive.
221  * That commonly entails turning off IRQs and DMA; there may be rules
222  * about how to quiesce that are specific to the bus or the device's type.
223  * (For example, network drivers mark the link state.)  Other details may
224  * differ according to the message:
225  *
226  * SUSPEND	Quiesce, enter a low power device state appropriate for
227  * 		the upcoming system state (such as PCI_D3hot), and enable
228  * 		wakeup events as appropriate.
229  *
230  * FREEZE	Quiesce operations so that a consistent image can be saved;
231  * 		but do NOT otherwise enter a low power device state, and do
232  * 		NOT emit system wakeup events.
233  *
234  * PRETHAW	Quiesce as if for FREEZE; additionally, prepare for restoring
235  * 		the system from a snapshot taken after an earlier FREEZE.
236  * 		Some drivers will need to reset their hardware state instead
237  * 		of preserving it, to ensure that it's never mistaken for the
238  * 		state which that earlier snapshot had set up.
239  *
240  * A minimally power-aware driver treats all messages as SUSPEND, fully
241  * reinitializes its device during resume() -- whether or not it was reset
242  * during the suspend/resume cycle -- and can't issue wakeup events.
243  *
244  * More power-aware drivers may also use low power states at runtime as
245  * well as during system sleep states like PM_SUSPEND_STANDBY.  They may
246  * be able to use wakeup events to exit from runtime low-power states,
247  * or from system low-power states such as standby or suspend-to-RAM.
248  */
249 
250 #define PM_EVENT_ON 0
251 #define PM_EVENT_FREEZE 1
252 #define PM_EVENT_SUSPEND 2
253 #define PM_EVENT_PRETHAW 3
254 
255 #define PMSG_FREEZE	((struct pm_message){ .event = PM_EVENT_FREEZE, })
256 #define PMSG_PRETHAW	((struct pm_message){ .event = PM_EVENT_PRETHAW, })
257 #define PMSG_SUSPEND	((struct pm_message){ .event = PM_EVENT_SUSPEND, })
258 #define PMSG_ON		((struct pm_message){ .event = PM_EVENT_ON, })
259 
260 struct dev_pm_info {
261 	pm_message_t		power_state;
262 	unsigned		can_wakeup:1;
263 #ifdef	CONFIG_PM
264 	unsigned		should_wakeup:1;
265 	pm_message_t		prev_state;
266 	void			* saved_state;
267 	struct device		* pm_parent;
268 	struct list_head	entry;
269 #endif
270 };
271 
272 extern void device_pm_set_parent(struct device * dev, struct device * parent);
273 
274 extern int device_power_down(pm_message_t state);
275 extern void device_power_up(void);
276 extern void device_resume(void);
277 
278 #ifdef CONFIG_PM
279 extern suspend_disk_method_t pm_disk_mode;
280 
281 extern int device_suspend(pm_message_t state);
282 extern int device_prepare_suspend(pm_message_t state);
283 
284 #define device_set_wakeup_enable(dev,val) \
285 	((dev)->power.should_wakeup = !!(val))
286 #define device_may_wakeup(dev) \
287 	(device_can_wakeup(dev) && (dev)->power.should_wakeup)
288 
289 extern int dpm_runtime_suspend(struct device *, pm_message_t);
290 extern void dpm_runtime_resume(struct device *);
291 extern void __suspend_report_result(const char *function, void *fn, int ret);
292 
293 #define suspend_report_result(fn, ret)					\
294 	do {								\
295 		__suspend_report_result(__FUNCTION__, fn, ret);		\
296 	} while (0)
297 
298 /*
299  * Platform hook to activate device wakeup capability, if that's not already
300  * handled by enable_irq_wake() etc.
301  * Returns zero on success, else negative errno
302  */
303 extern int (*platform_enable_wakeup)(struct device *dev, int is_on);
304 
305 static inline int call_platform_enable_wakeup(struct device *dev, int is_on)
306 {
307 	if (platform_enable_wakeup)
308 		return (*platform_enable_wakeup)(dev, is_on);
309 	return 0;
310 }
311 
312 #else /* !CONFIG_PM */
313 
314 static inline int device_suspend(pm_message_t state)
315 {
316 	return 0;
317 }
318 
319 #define device_set_wakeup_enable(dev,val)	do{}while(0)
320 #define device_may_wakeup(dev)			(0)
321 
322 static inline int dpm_runtime_suspend(struct device * dev, pm_message_t state)
323 {
324 	return 0;
325 }
326 
327 static inline void dpm_runtime_resume(struct device * dev)
328 {
329 }
330 
331 #define suspend_report_result(fn, ret) do { } while (0)
332 
333 static inline int call_platform_enable_wakeup(struct device *dev, int is_on)
334 {
335 	return 0;
336 }
337 
338 #endif
339 
340 /* changes to device_may_wakeup take effect on the next pm state change.
341  * by default, devices should wakeup if they can.
342  */
343 #define device_can_wakeup(dev) \
344 	((dev)->power.can_wakeup)
345 #define device_init_wakeup(dev,val) \
346 	do { \
347 		device_can_wakeup(dev) = !!(val); \
348 		device_set_wakeup_enable(dev,val); \
349 	} while(0)
350 
351 #endif /* __KERNEL__ */
352 
353 #endif /* _LINUX_PM_H */
354