Tribblix: manual page: pm_busy

PM_BUSY_COMPONENT(9F) Kernel Functions for Drivers PM_BUSY_COMPONENT(9F)

NAME

pm_busy_component, pm_idle_component - control device component
availability for Power Management

SYNOPSIS

#include <sys/ddi.h>
#include <sys/sunddi.h>

int pm_busy_component(dev_info_t *dip, int component);

int pm_idle_component(dev_info_t *dip, int component);

INTERFACE LEVEL

illumos DDI specific (illumos DDI)

PARAMETERS

dip
Pointer to the device's dev_info structure.

component
The number of the component to be power-managed.

DESCRIPTION

The pm_busy_component() function sets component of dip to be busy.
Calls to pm_busy_component() are stacked, requiring a corresponding
number of calls to pm_idle_component() to make the component idle
again. When a device is busy it will not be power-managed by the
system.

The pm_idle_component() function marks component idle, recording the
time that component went idle. This function must be called once for
each call to pm_busy_component(). A component which is idle is
available to be power-managed by the system. The pm_idle_component()
function has no effect if the component is already idle, except to
update the system's notion of when the device went idle.

If these functions are called as a result of entry into the driver's
attach(9E), detach(9E) or power(9E) entry point, these functions must
be called from the same thread which entered attach(9E), detach(9E)
or power(9E).

RETURN VALUES

The pm_busy_component() and pm_idle_component() functions return:

DDI_SUCCESS
Successfully set the indicated component busy or idle.

DDI_FAILURE
Invalid component number component or the device has
no components.

CONTEXT

These functions can be called from user or kernel context. These
functions may also be called from interrupt context, providing they
are not the first Power Management function called by the driver.

ATTRIBUTES