The pm_raise_power(9f) function requests the Power Management framework to raise the power level of component of dip to at least level.
The state of the device should be examined before each physical access. The pm_raise_power(9f) function should be called to set a component to the required power level if the operation to be
performed requires the component to be at a power level higher than its current power level.
When pm_raise_power(9f) returns with success, the component is guaranteed to be at least at the requested power level. All devices that depend on this will be at their full power level. Since
the actual device power level may be higher than requested by the driver, the driver should not make any assumption about the absolute power level on successful return from pm_raise_power(9f).
The pm_raise_power(9f) function may cause re-entry of the driver power(9E)
to raise the power level. Deadlock may result if the driver locks are held across the call to pm_raise_power(9f).
The pm_lower_power(9f) function requests the Power Management framework to lower the power level of component of dip to at most level.
Normally, transitions to lower power levels are initiated by the Power Management framework based on component idleness. However, when detaching, the driver should also initiate reduced power levels by setting the power level of all device components to their lowest levels.
The pm_lower_power(9f) function is intended for this use only, and will return DDI_FAILURE if the driver is not detaching at the time of the call.
If automatic Power Management is disabled ( see dtpower(1m) and power.conf(4)) , pm_lower_power(9f) returns DDI_SUCCESS without changing the power level of the component. Otherwise, when pm_lower_power(9f)
returns with success, the component is guaranteed to be at most at the requested power level. Since the actual device power level may be lower than requested by the driver, the driver should not make any assumption about the absolute power level on successful return from pm_lower_power(9f).
The pm_lower_power(9f) may cause re-entry of the driver power(9E) to lower
the power level. Deadlock may result if the driver locks are held across the call to pm_raise_power(9f).
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