Standardized INF Keywords for Power Management
The power management standardized keywords are defined in the device driver INF file. The operating system reads these standardized keywords and adjusts the current power management capabilities of the device.
Both Network Adapter WDF Class Extension (NetAdapterCx) client drivers and traditional NDIS miniport device drivers use these power management keywords. However, some keywords are used exclusively by NetAdapterCx drivers while others are used exclusively by NDIS drivers as the following sections describe:
The traditional NDIS miniport device driver should always indicate the device's hardware power management capabilities to NDIS in the NDIS_MINIPORT_ADAPTER_GENERAL_ATTRIBUTES structure.
For more information about standardized INF keywords, see Standardized INF Keywords for Network Devices.
Power management keywords for NetAdapterCx and NDIS
The following standardized INF keywords are defined to enable or disable support for power management features of network adapters. They are used by both NetAdapterCx client drivers and traditional NDIS miniport device drivers.
A value that describes whether the device should be enabled to wake the computer when the device receives a magic packet. (A magic packet is a packet that contains 16 contiguous copies of the receiving network adapter's Ethernet address)
The columns in the table at the end of this topic describe the following attributes for enumeration keywords:
The following table describes the possible INF entries for the power management keywords used by NDIS and NetAdapterCx drivers.
|WakeOnPattern||Wake on pattern match||0||Disabled|
|WakeOnMagicPacket||Wake on magic packet||0||Disabled|
|PMWiFiRekeyOffload||WiFi rekeying offload||0||Disabled|
Power management keywords exclusive to NetAdapterCx
The following power management keywords are for NetAdapterCx client driver use only.
In addition to the standard WDF process for giving user control over the device idle and wake behavior as described in User Control of Device Idle and Wake Behavior, NetAdapterCx also defines a network device specific standardized INF keyword for allowing more control.
If a network device has both idle power down and wake on packet filter capabilities, this setting allows the user to decide when the device idle power down can happen.
*IdleRestriction is an enumeration standardized INF keyword and has the following attributes:
The following table describes the possible INF entries for the *IdleRestriction keyword.
|*IdleRestriction||idle power down restriction||0 (Default)||No Restriction|
|1||Only idle when user is not present|
Power management keywords exclusive to NDIS
The following power management keywords are for traditional NDIS miniport driver use only. They must not be used by NetAdapterCx client drivers.
A value that describes whether the device should be enabled to wake the computer when the device receives a magic paket and the system is in the S0ix power state. This does not apply when the system is in the S4 power state.
*ModernStandbyWoLMagicPacket is supported in NDIS 6.60 and later, or Windows 10, version 1607 and later.
A value that describes whether the device should be enabled to put the device into a low-power state (sleep state) when media is disconnected and return to a full-power state (wake state) when media is connected again.
The following table describes the possible INF entries for the power management keywords used by NDIS miniport drivers.
|ModernStandbyWoLMagicPacket||Wake on magic packet when system is in the S0ix power state||0 (Default)||Disabled|
|DeviceSleepOnDisconnect||Device sleep on disconnect||0||Disabled|