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 Copyright (c) 2004, Sun Microsystems, Inc., All Rights Reserved.
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 PM_BUSY_COMPONENT 9F "Jul 21, 2004"
 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
See attributes(7) for descriptions of the following attributes:






ATTRIBUTE TYPE ATTRIBUTE VALUE
Interface stability Committed



 SEE ALSO
 pm (4D),  power.conf (5),  attach (9E),  detach (9E),  power (9E),  pm_raise_power (9F),  pm (9P),  pm-components (9P) 

Writing Device Drivers