Device Power Capabilities
IOCTL_POWER_CAPABILITIES queries device-specific characteristics including latency, power consumption, system wake, and inrush, from the device driver during Plug and Play enumeration. The device driver also reports which device power states it supports in its response to this IOCTL. The Power Manager generally does not request that a device go into a power state that it does not support. However, a driver developer for cross-platform devices should not assume such requests will not occur. Because the platform manufacturer can customize the Power Manager, the platform manufacturer may choose to ignore the DeviceDx field of the POWER_CAPABILITIES structure.
See Also
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