xref: /linux-6.15/include/linux/pm.h (revision d289bf7b)
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 #include <asm/errno.h>
29 
30 /*
31  * Power management requests... these are passed to pm_send_all() and friends.
32  *
33  * these functions are old and deprecated, see below.
34  */
35 typedef int __bitwise pm_request_t;
36 
37 #define PM_SUSPEND	((__force pm_request_t) 1)	/* enter D1-D3 */
38 #define PM_RESUME	((__force pm_request_t) 2)	/* enter D0 */
39 
40 
41 /*
42  * Device types... these are passed to pm_register
43  */
44 typedef int __bitwise pm_dev_t;
45 
46 #define PM_UNKNOWN_DEV	((__force pm_dev_t) 0)	/* generic */
47 #define PM_SYS_DEV	((__force pm_dev_t) 1)	/* system device (fan, KB controller, ...) */
48 #define PM_PCI_DEV	((__force pm_dev_t) 2)	/* PCI device */
49 #define PM_USB_DEV	((__force pm_dev_t) 3)	/* USB device */
50 #define PM_SCSI_DEV	((__force pm_dev_t) 4)	/* SCSI device */
51 #define PM_ISA_DEV	((__force pm_dev_t) 5)	/* ISA device */
52 #define	PM_MTD_DEV	((__force pm_dev_t) 6)	/* Memory Technology Device */
53 
54 /*
55  * System device hardware ID (PnP) values
56  */
57 enum
58 {
59 	PM_SYS_UNKNOWN = 0x00000000, /* generic */
60 	PM_SYS_KBC =	 0x41d00303, /* keyboard controller */
61 	PM_SYS_COM =	 0x41d00500, /* serial port */
62 	PM_SYS_IRDA =	 0x41d00510, /* IRDA controller */
63 	PM_SYS_FDC =	 0x41d00700, /* floppy controller */
64 	PM_SYS_VGA =	 0x41d00900, /* VGA controller */
65 	PM_SYS_PCMCIA =	 0x41d00e00, /* PCMCIA controller */
66 };
67 
68 /*
69  * Device identifier
70  */
71 #define PM_PCI_ID(dev) ((dev)->bus->number << 16 | (dev)->devfn)
72 
73 /*
74  * Request handler callback
75  */
76 struct pm_dev;
77 
78 typedef int (*pm_callback)(struct pm_dev *dev, pm_request_t rqst, void *data);
79 
80 /*
81  * Dynamic device information
82  */
83 struct pm_dev
84 {
85 	pm_dev_t	 type;
86 	unsigned long	 id;
87 	pm_callback	 callback;
88 	void		*data;
89 
90 	unsigned long	 flags;
91 	unsigned long	 state;
92 	unsigned long	 prev_state;
93 
94 	struct list_head entry;
95 };
96 
97 /* Functions above this comment are list-based old-style power
98  * management. Please avoid using them.  */
99 
100 /*
101  * Callbacks for platform drivers to implement.
102  */
103 extern void (*pm_idle)(void);
104 extern void (*pm_power_off)(void);
105 extern void (*pm_power_off_prepare)(void);
106 
107 /*
108  * Device power management
109  */
110 
111 struct device;
112 
113 typedef struct pm_message {
114 	int event;
115 } pm_message_t;
116 
117 /*
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).
124  *
125  * One transition is triggered by resume(), after a suspend() call; the
126  * message is implicit:
127  *
128  * ON		Driver starts working again, responding to hardware events
129  * 		and software requests.  The hardware may have gone through
130  * 		a power-off reset, or it may have maintained state from the
131  * 		previous suspend() which the driver will rely on while
132  * 		resuming.  On most platforms, there are no restrictions on
133  * 		availability of resources like clocks during resume().
134  *
135  * Other transitions are triggered by messages sent using suspend().  All
136  * these transitions quiesce the driver, so that I/O queues are inactive.
137  * That commonly entails turning off IRQs and DMA; there may be rules
138  * about how to quiesce that are specific to the bus or the device's type.
139  * (For example, network drivers mark the link state.)  Other details may
140  * differ according to the message:
141  *
142  * SUSPEND	Quiesce, enter a low power device state appropriate for
143  * 		the upcoming system state (such as PCI_D3hot), and enable
144  * 		wakeup events as appropriate.
145  *
146  * HIBERNATE	Enter a low power device state appropriate for the hibernation
147  * 		state (eg. ACPI S4) and enable wakeup events as appropriate.
148  *
149  * FREEZE	Quiesce operations so that a consistent image can be saved;
150  * 		but do NOT otherwise enter a low power device state, and do
151  * 		NOT emit system wakeup events.
152  *
153  * PRETHAW	Quiesce as if for FREEZE; additionally, prepare for restoring
154  * 		the system from a snapshot taken after an earlier FREEZE.
155  * 		Some drivers will need to reset their hardware state instead
156  * 		of preserving it, to ensure that it's never mistaken for the
157  * 		state which that earlier snapshot had set up.
158  *
159  * A minimally power-aware driver treats all messages as SUSPEND, fully
160  * reinitializes its device during resume() -- whether or not it was reset
161  * during the suspend/resume cycle -- and can't issue wakeup events.
162  *
163  * More power-aware drivers may also use low power states at runtime as
164  * well as during system sleep states like PM_SUSPEND_STANDBY.  They may
165  * be able to use wakeup events to exit from runtime low-power states,
166  * or from system low-power states such as standby or suspend-to-RAM.
167  */
168 
169 #define PM_EVENT_ON 0
170 #define PM_EVENT_FREEZE 1
171 #define PM_EVENT_SUSPEND 2
172 #define PM_EVENT_HIBERNATE 4
173 #define PM_EVENT_PRETHAW 8
174 
175 #define PM_EVENT_SLEEP	(PM_EVENT_SUSPEND | PM_EVENT_HIBERNATE)
176 
177 #define PMSG_FREEZE	((struct pm_message){ .event = PM_EVENT_FREEZE, })
178 #define PMSG_PRETHAW	((struct pm_message){ .event = PM_EVENT_PRETHAW, })
179 #define PMSG_SUSPEND	((struct pm_message){ .event = PM_EVENT_SUSPEND, })
180 #define PMSG_HIBERNATE	((struct pm_message){ .event = PM_EVENT_HIBERNATE, })
181 #define PMSG_ON		((struct pm_message){ .event = PM_EVENT_ON, })
182 
183 struct dev_pm_info {
184 	pm_message_t		power_state;
185 	unsigned		can_wakeup:1;
186 #ifdef	CONFIG_PM_SLEEP
187 	unsigned		should_wakeup:1;
188 	struct list_head	entry;
189 #endif
190 };
191 
192 extern int device_power_down(pm_message_t state);
193 extern void device_power_up(void);
194 extern void device_resume(void);
195 
196 #ifdef CONFIG_PM_SLEEP
197 extern int device_suspend(pm_message_t state);
198 extern int device_prepare_suspend(pm_message_t state);
199 
200 #define device_set_wakeup_enable(dev,val) \
201 	((dev)->power.should_wakeup = !!(val))
202 #define device_may_wakeup(dev) \
203 	(device_can_wakeup(dev) && (dev)->power.should_wakeup)
204 
205 extern void __suspend_report_result(const char *function, void *fn, int ret);
206 
207 #define suspend_report_result(fn, ret)					\
208 	do {								\
209 		__suspend_report_result(__FUNCTION__, fn, ret);		\
210 	} while (0)
211 
212 /*
213  * Platform hook to activate device wakeup capability, if that's not already
214  * handled by enable_irq_wake() etc.
215  * Returns zero on success, else negative errno
216  */
217 extern int (*platform_enable_wakeup)(struct device *dev, int is_on);
218 
219 static inline int call_platform_enable_wakeup(struct device *dev, int is_on)
220 {
221 	if (platform_enable_wakeup)
222 		return (*platform_enable_wakeup)(dev, is_on);
223 	return 0;
224 }
225 
226 #else /* !CONFIG_PM_SLEEP */
227 
228 static inline int device_suspend(pm_message_t state)
229 {
230 	return 0;
231 }
232 
233 #define device_set_wakeup_enable(dev,val)	do{}while(0)
234 #define device_may_wakeup(dev)			(0)
235 
236 #define suspend_report_result(fn, ret) do { } while (0)
237 
238 static inline int call_platform_enable_wakeup(struct device *dev, int is_on)
239 {
240 	return 0;
241 }
242 
243 #endif /* !CONFIG_PM_SLEEP */
244 
245 /* changes to device_may_wakeup take effect on the next pm state change.
246  * by default, devices should wakeup if they can.
247  */
248 #define device_can_wakeup(dev) \
249 	((dev)->power.can_wakeup)
250 #define device_init_wakeup(dev,val) \
251 	do { \
252 		device_can_wakeup(dev) = !!(val); \
253 		device_set_wakeup_enable(dev,val); \
254 	} while(0)
255 
256 /*
257  * Global Power Management flags
258  * Used to keep APM and ACPI from both being active
259  */
260 extern unsigned int	pm_flags;
261 
262 #define PM_APM	1
263 #define PM_ACPI	2
264 
265 #endif /* __KERNEL__ */
266 
267 #endif /* _LINUX_PM_H */
268