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

       Solaris DDI specific (Solaris DDI)

PARAMETERS

   pm_busy_component()
       dip	       Pointer to the device's dev_info structure.

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

   pm_idle_component()
       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 num-
       ber 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() func-
       tion has no effect if the component is already idle, except to update the system's notion of when the device went idle.

       Note -  If these functions are called as a result of entry into the driver's attach(9E), detach(9E) or power(9E) entry point,  these  func-
	       tions 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(5) for descriptions of the following attributes:

       +-----------------------------+-----------------------------+
       |      ATTRIBUTE TYPE	     |	    ATTRIBUTE VALUE	   |
       +-----------------------------+-----------------------------+
       |Interface stability	     |Evolving			   |
       +-----------------------------+-----------------------------+

SEE ALSO

       power.conf(4), pm(7D), attach(9E), detach(9E), power(9E), pm_raise_power(9F), pm(9P), pm-components(9P)

       Writing Device Drivers

SunOS 5.10							   21 July 2004 					     pm_busy_component(9F)