#define PM_DISK_PLATFORM ((__force suspend_disk_method_t) 2)
#define PM_DISK_SHUTDOWN ((__force suspend_disk_method_t) 3)
#define PM_DISK_REBOOT ((__force suspend_disk_method_t) 4)
-#define PM_DISK_MAX ((__force suspend_disk_method_t) 5)
-
+#define PM_DISK_TEST ((__force suspend_disk_method_t) 5)
+#define PM_DISK_TESTPROC ((__force suspend_disk_method_t) 6)
+#define PM_DISK_MAX ((__force suspend_disk_method_t) 7)
+
+/**
+ * struct pm_ops - Callbacks for managing platform dependent suspend states.
+ * @valid: Callback to determine whether the given state can be entered.
+ * If %CONFIG_SOFTWARE_SUSPEND is set then %PM_SUSPEND_DISK is
+ * always valid and never passed to this call.
+ * If not assigned, all suspend states are advertised as valid
+ * in /sys/power/state (but can still be rejected by prepare or enter.)
+ *
+ * @prepare: Prepare the platform for the given suspend state. Can return a
+ * negative error code if necessary.
+ *
+ * @enter: Enter the given suspend state, must be assigned. Can return a
+ * negative error code if necessary.
+ *
+ * @finish: Called when the system has left the given state and all devices
+ * are resumed. The return value is ignored.
+ *
+ * @pm_disk_mode: Set to the disk method that the user should be able to
+ * configure for suspend-to-disk. Since %PM_DISK_SHUTDOWN,
+ * %PM_DISK_REBOOT, %PM_DISK_TEST and %PM_DISK_TESTPROC
+ * are always allowed, currently only %PM_DISK_PLATFORM
+ * makes sense. If the user then choses %PM_DISK_PLATFORM,
+ * the @prepare call will be called before suspending to disk
+ * (if present), the @enter call should be present and will
+ * be called after all state has been saved and the machine
+ * is ready to be shut down/suspended/..., and the @finish
+ * callback is called after state has been restored. All
+ * these calls are called with %PM_SUSPEND_DISK as the state.
+ */
struct pm_ops {
- suspend_disk_method_t pm_disk_mode;
int (*valid)(suspend_state_t state);
int (*prepare)(suspend_state_t state);
int (*enter)(suspend_state_t state);
int (*finish)(suspend_state_t state);
+ suspend_disk_method_t pm_disk_mode;
};
-extern void pm_set_ops(struct pm_ops *);
+/**
+ * pm_set_ops - set platform dependent power management ops
+ * @pm_ops: The new power management operations to set.
+ */
+extern void pm_set_ops(struct pm_ops *pm_ops);
extern struct pm_ops *pm_ops;
extern int pm_suspend(suspend_state_t state);
} pm_message_t;
/*
- * There are 4 important states driver can be in:
- * ON -- driver is working
- * FREEZE -- stop operations and apply whatever policy is applicable to a
- * suspended driver of that class, freeze queues for block like IDE
- * does, drop packets for ethernet, etc... stop DMA engine too etc...
- * so a consistent image can be saved; but do not power any hardware
- * down.
- * SUSPEND - like FREEZE, but hardware is doing as much powersaving as
- * possible. Roughly pci D3.
- *
- * Unfortunately, current drivers only recognize numeric values 0 (ON) and 3
- * (SUSPEND). We'll need to fix the drivers. So yes, putting 3 to all different
- * defines is intentional, and will go away as soon as drivers are fixed. Also
- * note that typedef is neccessary, we'll probably want to switch to
- * typedef struct pm_message_t { int event; int flags; } pm_message_t
- * or something similar soon.
+ * Several driver power state transitions are externally visible, affecting
+ * the state of pending I/O queues and (for drivers that touch hardware)
+ * interrupts, wakeups, DMA, and other hardware state. There may also be
+ * internal transitions to various low power modes, which are transparent
+ * to the rest of the driver stack (such as a driver that's ON gating off
+ * clocks which are not in active use).
+ *
+ * One transition is triggered by resume(), after a suspend() call; the
+ * message is implicit:
+ *
+ * ON Driver starts working again, responding to hardware events
+ * and software requests. The hardware may have gone through
+ * a power-off reset, or it may have maintained state from the
+ * previous suspend() which the driver will rely on while
+ * resuming. On most platforms, there are no restrictions on
+ * availability of resources like clocks during resume().
+ *
+ * Other transitions are triggered by messages sent using suspend(). All
+ * these transitions quiesce the driver, so that I/O queues are inactive.
+ * That commonly entails turning off IRQs and DMA; there may be rules
+ * about how to quiesce that are specific to the bus or the device's type.
+ * (For example, network drivers mark the link state.) Other details may
+ * differ according to the message:
+ *
+ * SUSPEND Quiesce, enter a low power device state appropriate for
+ * the upcoming system state (such as PCI_D3hot), and enable
+ * wakeup events as appropriate.
+ *
+ * FREEZE Quiesce operations so that a consistent image can be saved;
+ * but do NOT otherwise enter a low power device state, and do
+ * NOT emit system wakeup events.
+ *
+ * PRETHAW Quiesce as if for FREEZE; additionally, prepare for restoring
+ * the system from a snapshot taken after an earlier FREEZE.
+ * Some drivers will need to reset their hardware state instead
+ * of preserving it, to ensure that it's never mistaken for the
+ * state which that earlier snapshot had set up.
+ *
+ * A minimally power-aware driver treats all messages as SUSPEND, fully
+ * reinitializes its device during resume() -- whether or not it was reset
+ * during the suspend/resume cycle -- and can't issue wakeup events.
+ *
+ * More power-aware drivers may also use low power states at runtime as
+ * well as during system sleep states like PM_SUSPEND_STANDBY. They may
+ * be able to use wakeup events to exit from runtime low-power states,
+ * or from system low-power states such as standby or suspend-to-RAM.
*/
#define PM_EVENT_ON 0
#define PM_EVENT_FREEZE 1
#define PM_EVENT_SUSPEND 2
+#define PM_EVENT_PRETHAW 3
#define PMSG_FREEZE ((struct pm_message){ .event = PM_EVENT_FREEZE, })
+#define PMSG_PRETHAW ((struct pm_message){ .event = PM_EVENT_PRETHAW, })
#define PMSG_SUSPEND ((struct pm_message){ .event = PM_EVENT_SUSPEND, })
#define PMSG_ON ((struct pm_message){ .event = PM_EVENT_ON, })
extern suspend_disk_method_t pm_disk_mode;
extern int device_suspend(pm_message_t state);
+extern int device_prepare_suspend(pm_message_t state);
#define device_set_wakeup_enable(dev,val) \
((dev)->power.should_wakeup = !!(val))
projects / powerpc.git / blobdiff