Man page 9 : enum_ieee80211_hw_flags

enum_ieee80211_hw_flags - hardware flags

IEEE80211_HW_HAS_RATE_CONTROL
    The hardware or firmware includes rate control, and cannot be controlled by the stack. As such, no rate control algorithm should be instantiated, and the TX rate reported to userspace will be taken from the TX status instead of the rate control algorithm. Note that this requires that the driver implement a number of callbacks so it has the correct information, it needs to have the set_rts_threshold callback and must look at the BSS config use_cts_prot for G/N protection, use_short_slot for slot timing in 2.4 GHz and use_short_preamble for preambles for CCK frames.

IEEE80211_HW_RX_INCLUDES_FCS
    Indicates that received frames passed to the stack include the FCS at the end.

IEEE80211_HW_HOST_BROADCAST_PS_BUFFERING
    Some wireless LAN chipsets buffer broadcast/multicast frames for power saving stations in the hardware/firmware and others rely on the host system for such buffering. This option is used to configure the IEEE 802.11 upper layer to buffer broadcast and multicast frames when there are power saving stations so that the driver can fetch them with ieee80211_get_buffered_bc.

IEEE80211_HW_2GHZ_SHORT_SLOT_INCAPABLE
    Hardware is not capable of short slot operation on the 2.4 GHz band.

IEEE80211_HW_2GHZ_SHORT_PREAMBLE_INCAPABLE
    Hardware is not capable of receiving frames with short preamble on the 2.4 GHz band.

IEEE80211_HW_SIGNAL_UNSPEC
    Hardware can provide signal values but we donAqt know its units. We expect values between 0 and max_signal. If possible please provide dB or dBm instead.

IEEE80211_HW_SIGNAL_DBM
    Hardware gives signal values in dBm, decibel difference from one milliwatt. This is the preferred method since it is standardized between different devices. max_signal does not need to be set.

IEEE80211_HW_NEED_DTIM_BEFORE_ASSOC
    This device needs to get data from beacon before association (i.e. dtim_period).

IEEE80211_HW_SPECTRUM_MGMT
    Hardware supports spectrum management defined in 802.11h Measurement, Channel Switch, Quieting, TPC

IEEE80211_HW_AMPDU_AGGREGATION
    Hardware supports 11n A-MPDU aggregation.

IEEE80211_HW_SUPPORTS_PS
    Hardware has power save support (i.e. can go to sleep).

IEEE80211_HW_PS_NULLFUNC_STACK
    Hardware requires nullfunc frame handling in stack, implies stack support for dynamic PS.

IEEE80211_HW_SUPPORTS_DYNAMIC_PS
    Hardware has support for dynamic PS.

IEEE80211_HW_MFP_CAPABLE
    Hardware supports management frame protection (MFP, IEEE 802.11w).

IEEE80211_HW_WANT_MONITOR_VIF
    The driver would like to be informed of a virtual monitor interface when monitor interfaces are the only active interfaces.

IEEE80211_HW_SUPPORTS_STATIC_SMPS
    Hardware supports static spatial multiplexing powersave, ie. can turn off all but one chain even on HT connections that should be using more chains.

IEEE80211_HW_SUPPORTS_DYNAMIC_SMPS
    Hardware supports dynamic spatial multiplexing powersave, ie. can turn off all but one chain and then wake the rest up as required after, for example, rts/cts handshake.

IEEE80211_HW_SUPPORTS_UAPSD
    Hardware supports Unscheduled Automatic Power Save Delivery (U-APSD) in managed mode. The mode is configured with conf_tx operation.

IEEE80211_HW_REPORTS_TX_ACK_STATUS
    Hardware can provide ack status reports of Tx frames to the stack.

IEEE80211_HW_CONNECTION_MONITOR
    The hardware performs its own connection monitoring, including periodic keep-alives to the AP and probing the AP on beacon loss. When this flag is set, signaling beacon-loss will cause an immediate change to disassociated state.

IEEE80211_HW_QUEUE_CONTROL
    The driver wants to control per-interface queue mapping in order to use different queues (not just one per AC) for different virtual interfaces. See the doc section on HW queue control for more details.

IEEE80211_HW_SUPPORTS_PER_STA_GTK
    The deviceAqs crypto engine supports per-station GTKs as used by IBSS RSN or during fast transition. If the device doesnAqt support per-station GTKs, but can be asked not to decrypt group addressed frames, then IBSS RSN support is still possible but software crypto will be used. Advertise the wiphy flag only in that case.

IEEE80211_HW_AP_LINK_PS
    When operating in AP mode the device autonomously manages the PS status of connected stations. When this flag is set mac80211 will not trigger PS mode for connected stations based on the PM bit of incoming frames. Use ieee80211_start_ps/ieee8021_end_ps to manually configure the PS mode of connected stations.

IEEE80211_HW_TX_AMPDU_SETUP_IN_HW
    The device handles TX A-MPDU session setup strictly in HW. mac80211 should not attempt to do this in software.

IEEE80211_HW_SUPPORTS_RC_TABLE
    The driver supports using a rate selection table provided by the rate control algorithm.

IEEE80211_HW_P2P_DEV_ADDR_FOR_INTF
    Use the P2P Device address for any P2P Interface. This will be honoured even if more than one interface is supported.

IEEE80211_HW_TIMING_BEACON_ONLY
    Use sync timing from beacon frames only, to allow getting TBTT of a DTIM beacon.

These flags are used to indicate hardware capabilities to the stack. Generally, flags here should have their meaning done in a way that the simplest hardware doesnAqt need setting any particular flags. There are some exceptions to this rule, however, so you are advised to review these flags carefully.

Johannes Berg <>
    Author.