include/linux/pm.h

   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 extern void (*pm_power_off_prepare)(void);
 105
 106 typedef int __bitwise suspend_state_t;
 107
 108 #define PM_SUSPEND_ON           ((__force suspend_state_t) 0)
 109 #define PM_SUSPEND_STANDBY      ((__force suspend_state_t) 1)
 110 #define PM_SUSPEND_MEM          ((__force suspend_state_t) 3)
 111 #define PM_SUSPEND_MAX          ((__force suspend_state_t) 4)
 112
 113 /**
 114  * struct pm_ops - Callbacks for managing platform dependent system sleep
 115  *      states.
 116  *
 117  * @valid: Callback to determine if given system sleep state is supported by
 118  *      the platform.
 119  *      Valid (ie. supported) states are advertised in /sys/power/state.  Note
 120  *      that it still may be impossible to enter given system sleep state if the
 121  *      conditions aren't right.
 122  *      There is the %pm_valid_only_mem function available that can be assigned
 123  *      to this if the platform only supports mem sleep.
 124  *
 125  * @set_target: Tell the platform which system sleep state is going to be
 126  *      entered.
 127  *      @set_target() is executed right prior to suspending devices.  The
 128  *      information conveyed to the platform code by @set_target() should be
 129  *      disregarded by the platform as soon as @finish() is executed and if
 130  *      @prepare() fails.  If @set_target() fails (ie. returns nonzero),
 131  *      @prepare(), @enter() and @finish() will not be called by the PM core.
 132  *      This callback is optional.  However, if it is implemented, the argument
 133  *      passed to @prepare(), @enter() and @finish() is meaningless and should
 134  *      be ignored.
 135  *
 136  * @prepare: Prepare the platform for entering the system sleep state indicated
 137  *      by @set_target() or represented by the argument if @set_target() is not
 138  *      implemented.
 139  *      @prepare() is called right after devices have been suspended (ie. the
 140  *      appropriate .suspend() method has been executed for each device) and
 141  *      before the nonboot CPUs are disabled (it is executed with IRQs enabled).
 142  *      This callback is optional.  It returns 0 on success or a negative
 143  *      error code otherwise, in which case the system cannot enter the desired
 144  *      sleep state (@enter() and @finish() will not be called in that case).
 145  *
 146  * @enter: Enter the system sleep state indicated by @set_target() or
 147  *      represented by the argument if @set_target() is not implemented.
 148  *      This callback is mandatory.  It returns 0 on success or a negative
 149  *      error code otherwise, in which case the system cannot enter the desired
 150  *      sleep state.
 151  *
 152  * @finish: Called when the system has just left a sleep state, right after
 153  *      the nonboot CPUs have been enabled and before devices are resumed (it is
 154  *      executed with IRQs enabled).  If @set_target() is not implemented, the
 155  *      argument represents the sleep state being left.
 156  *      This callback is optional, but should be implemented by the platforms
 157  *      that implement @prepare().  If implemented, it is always called after
 158  *      @enter() (even if @enter() fails).
 159  */
 160 struct pm_ops {
 161         int (*valid)(suspend_state_t state);
 162         int (*set_target)(suspend_state_t state);
 163         int (*prepare)(suspend_state_t state);
 164         int (*enter)(suspend_state_t state);
 165         int (*finish)(suspend_state_t state);
 166 };
 167
 168 extern struct pm_ops *pm_ops;
 169
 170 /**
 171  * pm_set_ops - set platform dependent power management ops
 172  * @pm_ops: The new power management operations to set.
 173  */
 174 extern void pm_set_ops(struct pm_ops *pm_ops);
 175 extern int pm_valid_only_mem(suspend_state_t state);
 176
 177 /**
 178  * arch_suspend_disable_irqs - disable IRQs for suspend
 179  *
 180  * Disables IRQs (in the default case). This is a weak symbol in the common
 181  * code and thus allows architectures to override it if more needs to be
 182  * done. Not called for suspend to disk.
 183  */
 184 extern void arch_suspend_disable_irqs(void);
 185
 186 /**
 187  * arch_suspend_enable_irqs - enable IRQs after suspend
 188  *
 189  * Enables IRQs (in the default case). This is a weak symbol in the common
 190  * code and thus allows architectures to override it if more needs to be
 191  * done. Not called for suspend to disk.
 192  */
 193 extern void arch_suspend_enable_irqs(void);
 194
 195 extern int pm_suspend(suspend_state_t state);
 196
 197 /*
 198  * Device power management
 199  */
 200
 201 struct device;
 202
 203 typedef struct pm_message {
 204         int event;
 205 } pm_message_t;
 206
 207 /*
 208  * Several driver power state transitions are externally visible, affecting
 209  * the state of pending I/O queues and (for drivers that touch hardware)
 210  * interrupts, wakeups, DMA, and other hardware state.  There may also be
 211  * internal transitions to various low power modes, which are transparent
 212  * to the rest of the driver stack (such as a driver that's ON gating off
 213  * clocks which are not in active use).
 214  *
 215  * One transition is triggered by resume(), after a suspend() call; the
 216  * message is implicit:
 217  *
 218  * ON           Driver starts working again, responding to hardware events
 219  *              and software requests.  The hardware may have gone through
 220  *              a power-off reset, or it may have maintained state from the
 221  *              previous suspend() which the driver will rely on while
 222  *              resuming.  On most platforms, there are no restrictions on
 223  *              availability of resources like clocks during resume().
 224  *
 225  * Other transitions are triggered by messages sent using suspend().  All
 226  * these transitions quiesce the driver, so that I/O queues are inactive.
 227  * That commonly entails turning off IRQs and DMA; there may be rules
 228  * about how to quiesce that are specific to the bus or the device's type.
 229  * (For example, network drivers mark the link state.)  Other details may
 230  * differ according to the message:
 231  *
 232  * SUSPEND      Quiesce, enter a low power device state appropriate for
 233  *              the upcoming system state (such as PCI_D3hot), and enable
 234  *              wakeup events as appropriate.
 235  *
 236  * FREEZE       Quiesce operations so that a consistent image can be saved;
 237  *              but do NOT otherwise enter a low power device state, and do
 238  *              NOT emit system wakeup events.
 239  *
 240  * PRETHAW      Quiesce as if for FREEZE; additionally, prepare for restoring
 241  *              the system from a snapshot taken after an earlier FREEZE.
 242  *              Some drivers will need to reset their hardware state instead
 243  *              of preserving it, to ensure that it's never mistaken for the
 244  *              state which that earlier snapshot had set up.
 245  *
 246  * A minimally power-aware driver treats all messages as SUSPEND, fully
 247  * reinitializes its device during resume() -- whether or not it was reset
 248  * during the suspend/resume cycle -- and can't issue wakeup events.
 249  *
 250  * More power-aware drivers may also use low power states at runtime as
 251  * well as during system sleep states like PM_SUSPEND_STANDBY.  They may
 252  * be able to use wakeup events to exit from runtime low-power states,
 253  * or from system low-power states such as standby or suspend-to-RAM.
 254  */
 255
 256 #define PM_EVENT_ON 0
 257 #define PM_EVENT_FREEZE 1
 258 #define PM_EVENT_SUSPEND 2
 259 #define PM_EVENT_PRETHAW 3
 260
 261 #define PMSG_FREEZE     ((struct pm_message){ .event = PM_EVENT_FREEZE, })
 262 #define PMSG_PRETHAW    ((struct pm_message){ .event = PM_EVENT_PRETHAW, })
 263 #define PMSG_SUSPEND    ((struct pm_message){ .event = PM_EVENT_SUSPEND, })
 264 #define PMSG_ON         ((struct pm_message){ .event = PM_EVENT_ON, })
 265
 266 struct dev_pm_info {
 267         pm_message_t            power_state;
 268         unsigned                can_wakeup:1;
 269 #ifdef  CONFIG_PM
 270         unsigned                should_wakeup:1;
 271         struct list_head        entry;
 272 #endif
 273 };
 274
 275 extern int device_power_down(pm_message_t state);
 276 extern void device_power_up(void);
 277 extern void device_resume(void);
 278
 279 #ifdef CONFIG_PM
 280 extern int device_suspend(pm_message_t state);
 281 extern int device_prepare_suspend(pm_message_t state);
 282
 283 #define device_set_wakeup_enable(dev,val) \
 284         ((dev)->power.should_wakeup = !!(val))
 285 #define device_may_wakeup(dev) \
 286         (device_can_wakeup(dev) && (dev)->power.should_wakeup)
 287
 288 extern void __suspend_report_result(const char *function, void *fn, int ret);
 289
 290 #define suspend_report_result(fn, ret)                                  \
 291         do {                                                            \
 292                 __suspend_report_result(__FUNCTION__, fn, ret);         \
 293         } while (0)
 294
 295 /*
 296  * Platform hook to activate device wakeup capability, if that's not already
 297  * handled by enable_irq_wake() etc.
 298  * Returns zero on success, else negative errno
 299  */
 300 extern int (*platform_enable_wakeup)(struct device *dev, int is_on);
 301
 302 static inline int call_platform_enable_wakeup(struct device *dev, int is_on)
 303 {
 304         if (platform_enable_wakeup)
 305                 return (*platform_enable_wakeup)(dev, is_on);
 306         return 0;
 307 }
 308
 309 #else /* !CONFIG_PM */
 310
 311 static inline int device_suspend(pm_message_t state)
 312 {
 313         return 0;
 314 }
 315
 316 #define device_set_wakeup_enable(dev,val)       do{}while(0)
 317 #define device_may_wakeup(dev)                  (0)
 318
 319 #define suspend_report_result(fn, ret) do { } while (0)
 320
 321 static inline int call_platform_enable_wakeup(struct device *dev, int is_on)
 322 {
 323         return 0;
 324 }
 325
 326 #endif
 327
 328 /* changes to device_may_wakeup take effect on the next pm state change.
 329  * by default, devices should wakeup if they can.
 330  */
 331 #define device_can_wakeup(dev) \
 332         ((dev)->power.can_wakeup)
 333 #define device_init_wakeup(dev,val) \
 334         do { \
 335                 device_can_wakeup(dev) = !!(val); \
 336                 device_set_wakeup_enable(dev,val); \
 337         } while(0)
 338
 339 #endif /* __KERNEL__ */
 340
 341 #endif /* _LINUX_PM_H */