int (*probe) (struct device * dev);
int (*remove) (struct device * dev);
- int (*suspend) (struct device * dev, pm_message_t state, u32 level);
- int (*resume) (struct device * dev, u32 level);
+ int (*suspend) (struct device * dev, pm_message_t state);
+ int (*resume) (struct device * dev);
};
A driver's probe() may return a negative errno value to indicate that
the driver did not bind to this device, in which case it should have
-released all reasources it allocated.
+released all resources it allocated.
int (*remove) (struct device * dev);
If the device is still present, it should quiesce the device and place
it into a supported low-power state.
- int (*suspend) (struct device * dev, pm_message_t state, u32 level);
+ int (*suspend) (struct device * dev, pm_message_t state);
-suspend is called to put the device in a low power state. There are
-several stages to successfully suspending a device, which is denoted in
-the @level parameter. Breaking the suspend transition into several
-stages affords the platform flexibility in performing device power
-management based on the requirements of the system and the
-user-defined policy.
+suspend is called to put the device in a low power state.
-SUSPEND_NOTIFY notifies the device that a suspend transition is about
-to happen. This happens on system power state transitions to verify
-that all devices can successfully suspend.
+ int (*resume) (struct device * dev);
-A driver may choose to fail on this call, which should cause the
-entire suspend transition to fail. A driver should fail only if it
-knows that the device will not be able to be resumed properly when the
-system wakes up again. It could also fail if it somehow determines it
-is in the middle of an operation too important to stop.
-
-SUSPEND_DISABLE tells the device to stop I/O transactions. When it
-stops transactions, or what it should do with unfinished transactions
-is a policy of the driver. After this call, the driver should not
-accept any other I/O requests.
-
-SUSPEND_SAVE_STATE tells the device to save the context of the
-hardware. This includes any bus-specific hardware state and
-device-specific hardware state. A pointer to this saved state can be
-stored in the device's saved_state field.
-
-SUSPEND_POWER_DOWN tells the driver to place the device in the low
-power state requested.
-
-Whether suspend is called with a given level is a policy of the
-platform. Some levels may be omitted; drivers must not assume the
-reception of any level. However, all levels must be called in the
-order above; i.e. notification will always come before disabling;
-disabling the device will come before suspending the device.
-
-All calls are made with interrupts enabled, except for the
-SUSPEND_POWER_DOWN level.
-
- int (*resume) (struct device * dev, u32 level);
-
-Resume is used to bring a device back from a low power state. Like the
-suspend transition, it happens in several stages.
-
-RESUME_POWER_ON tells the driver to set the power state to the state
-before the suspend call (The device could have already been in a low
-power state before the suspend call to put in a lower power state).
-
-RESUME_RESTORE_STATE tells the driver to restore the state saved by
-the SUSPEND_SAVE_STATE suspend call.
-
-RESUME_ENABLE tells the driver to start accepting I/O transactions
-again. Depending on driver policy, the device may already have pending
-I/O requests.
-
-RESUME_POWER_ON is called with interrupts disabled. The other resume
-levels are called with interrupts enabled.
-
-As with the various suspend stages, the driver must not assume that
-any other resume calls have been or will be made. Each call should be
-self-contained and not dependent on any external state.
+Resume is used to bring a device back from a low power state.
Attributes
~~~~~~~~~~
struct driver_attribute {
struct attribute attr;
- ssize_t (*show)(struct device_driver *, char * buf, size_t count, loff_t off);
- ssize_t (*store)(struct device_driver *, const char * buf, size_t count, loff_t off);
+ ssize_t (*show)(struct device_driver *driver, char *buf);
+ ssize_t (*store)(struct device_driver *, const char * buf, size_t count);
};
Device drivers can export attributes via their sysfs directories.
git.openpandora.org / pandora-kernel.git / blobdiff