mac80211.h 79.1 KB
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/*
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 * mac80211 <-> driver interface
 *
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 * Copyright 2002-2005, Devicescape Software, Inc.
 * Copyright 2006-2007	Jiri Benc <jbenc@suse.cz>
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 * Copyright 2007-2008	Johannes Berg <johannes@sipsolutions.net>
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 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */

#ifndef MAC80211_H
#define MAC80211_H

#include <linux/kernel.h>
#include <linux/if_ether.h>
#include <linux/skbuff.h>
#include <linux/wireless.h>
#include <linux/device.h>
#include <linux/ieee80211.h>
#include <net/cfg80211.h>

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/**
 * DOC: Introduction
 *
 * mac80211 is the Linux stack for 802.11 hardware that implements
 * only partial functionality in hard- or firmware. This document
 * defines the interface between mac80211 and low-level hardware
 * drivers.
 */

/**
 * DOC: Calling mac80211 from interrupts
 *
 * Only ieee80211_tx_status_irqsafe() and ieee80211_rx_irqsafe() can be
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 * called in hardware interrupt context. The low-level driver must not call any
 * other functions in hardware interrupt context. If there is a need for such
 * call, the low-level driver should first ACK the interrupt and perform the
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 * IEEE 802.11 code call after this, e.g. from a scheduled workqueue or even
 * tasklet function.
 *
 * NOTE: If the driver opts to use the _irqsafe() functions, it may not also
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 *	 use the non-IRQ-safe functions!
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 */

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/**
 * DOC: Warning
 *
 * If you're reading this document and not the header file itself, it will
 * be incomplete because not all documentation has been converted yet.
 */

/**
 * DOC: Frame format
 *
 * As a general rule, when frames are passed between mac80211 and the driver,
 * they start with the IEEE 802.11 header and include the same octets that are
 * sent over the air except for the FCS which should be calculated by the
 * hardware.
 *
 * There are, however, various exceptions to this rule for advanced features:
 *
 * The first exception is for hardware encryption and decryption offload
 * where the IV/ICV may or may not be generated in hardware.
 *
 * Secondly, when the hardware handles fragmentation, the frame handed to
 * the driver from mac80211 is the MSDU, not the MPDU.
 *
 * Finally, for received frames, the driver is able to indicate that it has
 * filled a radiotap header and put that in front of the frame; if it does
 * not do so then mac80211 may add this under certain circumstances.
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 */

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/**
 * enum ieee80211_max_queues - maximum number of queues
 *
 * @IEEE80211_MAX_QUEUES: Maximum number of regular device queues.
 */
enum ieee80211_max_queues {
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	IEEE80211_MAX_QUEUES =		4,
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};

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/**
 * struct ieee80211_tx_queue_params - transmit queue configuration
 *
 * The information provided in this structure is required for QoS
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 * transmit queue configuration. Cf. IEEE 802.11 7.3.2.29.
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 *
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 * @aifs: arbitration interframe space [0..255]
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 * @cw_min: minimum contention window [a value of the form
 *	2^n-1 in the range 1..32767]
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 * @cw_max: maximum contention window [like @cw_min]
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 * @txop: maximum burst time in units of 32 usecs, 0 meaning disabled
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 */
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struct ieee80211_tx_queue_params {
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	u16 txop;
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	u16 cw_min;
	u16 cw_max;
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	u8 aifs;
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};

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/**
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 * struct ieee80211_tx_queue_stats - transmit queue statistics
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 *
 * @len: number of packets in queue
 * @limit: queue length limit
 * @count: number of frames sent
 */
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struct ieee80211_tx_queue_stats {
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	unsigned int len;
	unsigned int limit;
	unsigned int count;
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};

struct ieee80211_low_level_stats {
	unsigned int dot11ACKFailureCount;
	unsigned int dot11RTSFailureCount;
	unsigned int dot11FCSErrorCount;
	unsigned int dot11RTSSuccessCount;
};

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/**
 * enum ieee80211_bss_change - BSS change notification flags
 *
 * These flags are used with the bss_info_changed() callback
 * to indicate which BSS parameter changed.
 *
 * @BSS_CHANGED_ASSOC: association status changed (associated/disassociated),
 *	also implies a change in the AID.
 * @BSS_CHANGED_ERP_CTS_PROT: CTS protection changed
 * @BSS_CHANGED_ERP_PREAMBLE: preamble changed
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 * @BSS_CHANGED_ERP_SLOT: slot timing changed
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 * @BSS_CHANGED_HT: 802.11n parameters changed
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 * @BSS_CHANGED_BASIC_RATES: Basic rateset changed
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 * @BSS_CHANGED_BEACON_INT: Beacon interval changed
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 * @BSS_CHANGED_BSSID: BSSID changed, for whatever
 *	reason (IBSS and managed mode)
 * @BSS_CHANGED_BEACON: Beacon data changed, retrieve
 *	new beacon (beaconing modes)
 * @BSS_CHANGED_BEACON_ENABLED: Beaconing should be
 *	enabled/disabled (beaconing modes)
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 */
enum ieee80211_bss_change {
	BSS_CHANGED_ASSOC		= 1<<0,
	BSS_CHANGED_ERP_CTS_PROT	= 1<<1,
	BSS_CHANGED_ERP_PREAMBLE	= 1<<2,
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	BSS_CHANGED_ERP_SLOT		= 1<<3,
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	BSS_CHANGED_HT                  = 1<<4,
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	BSS_CHANGED_BASIC_RATES		= 1<<5,
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	BSS_CHANGED_BEACON_INT		= 1<<6,
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	BSS_CHANGED_BSSID		= 1<<7,
	BSS_CHANGED_BEACON		= 1<<8,
	BSS_CHANGED_BEACON_ENABLED	= 1<<9,
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};

/**
 * struct ieee80211_bss_conf - holds the BSS's changing parameters
 *
 * This structure keeps information about a BSS (and an association
 * to that BSS) that can change during the lifetime of the BSS.
 *
 * @assoc: association status
 * @aid: association ID number, valid only when @assoc is true
 * @use_cts_prot: use CTS protection
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 * @use_short_preamble: use 802.11b short preamble;
 *	if the hardware cannot handle this it must set the
 *	IEEE80211_HW_2GHZ_SHORT_PREAMBLE_INCAPABLE hardware flag
 * @use_short_slot: use short slot time (only relevant for ERP);
 *	if the hardware cannot handle this it must set the
 *	IEEE80211_HW_2GHZ_SHORT_SLOT_INCAPABLE hardware flag
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 * @dtim_period: num of beacons before the next DTIM, for PSM
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 * @timestamp: beacon timestamp
 * @beacon_int: beacon interval
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 * @assoc_capability: capabilities taken from assoc resp
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 * @basic_rates: bitmap of basic rates, each bit stands for an
 *	index into the rate table configured by the driver in
 *	the current band.
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 * @bssid: The BSSID for this BSS
 * @enable_beacon: whether beaconing should be enabled or not
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 * @ht_operation_mode: HT operation mode (like in &struct ieee80211_ht_info).
 *	This field is only valid when the channel type is one of the HT types.
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 */
struct ieee80211_bss_conf {
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	const u8 *bssid;
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	/* association related data */
	bool assoc;
	u16 aid;
	/* erp related data */
	bool use_cts_prot;
	bool use_short_preamble;
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	bool use_short_slot;
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	bool enable_beacon;
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	u8 dtim_period;
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	u16 beacon_int;
	u16 assoc_capability;
	u64 timestamp;
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	u32 basic_rates;
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	u16 ht_operation_mode;
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};

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/**
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 * enum mac80211_tx_control_flags - flags to describe transmission information/status
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 *
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 * These flags are used with the @flags member of &ieee80211_tx_info.
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 *
 * @IEEE80211_TX_CTL_REQ_TX_STATUS: request TX status callback for this frame.
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 * @IEEE80211_TX_CTL_ASSIGN_SEQ: The driver has to assign a sequence
 *	number to this frame, taking care of not overwriting the fragment
 *	number and increasing the sequence number only when the
 *	IEEE80211_TX_CTL_FIRST_FRAGMENT flag is set. mac80211 will properly
 *	assign sequence numbers to QoS-data frames but cannot do so correctly
 *	for non-QoS-data and management frames because beacons need them from
 *	that counter as well and mac80211 cannot guarantee proper sequencing.
 *	If this flag is set, the driver should instruct the hardware to
 *	assign a sequence number to the frame or assign one itself. Cf. IEEE
 *	802.11-2007 7.1.3.4.1 paragraph 3. This flag will always be set for
 *	beacons and always be clear for frames without a sequence number field.
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 * @IEEE80211_TX_CTL_NO_ACK: tell the low level not to wait for an ack
 * @IEEE80211_TX_CTL_CLEAR_PS_FILT: clear powersave filter for destination
 *	station
 * @IEEE80211_TX_CTL_FIRST_FRAGMENT: this is a first fragment of the frame
 * @IEEE80211_TX_CTL_SEND_AFTER_DTIM: send this frame after DTIM beacon
 * @IEEE80211_TX_CTL_AMPDU: this frame should be sent as part of an A-MPDU
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 * @IEEE80211_TX_CTL_INJECTED: Frame was injected, internal to mac80211.
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 * @IEEE80211_TX_STAT_TX_FILTERED: The frame was not transmitted
 *	because the destination STA was in powersave mode.
 * @IEEE80211_TX_STAT_ACK: Frame was acknowledged
 * @IEEE80211_TX_STAT_AMPDU: The frame was aggregated, so status
 * 	is for the whole aggregation.
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 * @IEEE80211_TX_STAT_AMPDU_NO_BACK: no block ack was returned,
 * 	so consider using block ack request (BAR).
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 * @IEEE80211_TX_CTL_RATE_CTRL_PROBE: internal to mac80211, can be
 *	set by rate control algorithms to indicate probe rate, will
 *	be cleared for fragmented frames (except on the last fragment)
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 * @IEEE80211_TX_INTFL_RCALGO: mac80211 internal flag, do not test or
 *	set this flag in the driver; indicates that the rate control
 *	algorithm was used and should be notified of TX status
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 * @IEEE80211_TX_INTFL_NEED_TXPROCESSING: completely internal to mac80211,
 *	used to indicate that a pending frame requires TX processing before
 *	it can be sent out.
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 */
enum mac80211_tx_control_flags {
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	IEEE80211_TX_CTL_REQ_TX_STATUS		= BIT(0),
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	IEEE80211_TX_CTL_ASSIGN_SEQ		= BIT(1),
	IEEE80211_TX_CTL_NO_ACK			= BIT(2),
	IEEE80211_TX_CTL_CLEAR_PS_FILT		= BIT(3),
	IEEE80211_TX_CTL_FIRST_FRAGMENT		= BIT(4),
	IEEE80211_TX_CTL_SEND_AFTER_DTIM	= BIT(5),
	IEEE80211_TX_CTL_AMPDU			= BIT(6),
	IEEE80211_TX_CTL_INJECTED		= BIT(7),
	IEEE80211_TX_STAT_TX_FILTERED		= BIT(8),
	IEEE80211_TX_STAT_ACK			= BIT(9),
	IEEE80211_TX_STAT_AMPDU			= BIT(10),
	IEEE80211_TX_STAT_AMPDU_NO_BACK		= BIT(11),
	IEEE80211_TX_CTL_RATE_CTRL_PROBE	= BIT(12),
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	IEEE80211_TX_INTFL_RCALGO		= BIT(13),
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	IEEE80211_TX_INTFL_NEED_TXPROCESSING	= BIT(14),
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};

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/**
 * enum mac80211_rate_control_flags - per-rate flags set by the
 *	Rate Control algorithm.
 *
 * These flags are set by the Rate control algorithm for each rate during tx,
 * in the @flags member of struct ieee80211_tx_rate.
 *
 * @IEEE80211_TX_RC_USE_RTS_CTS: Use RTS/CTS exchange for this rate.
 * @IEEE80211_TX_RC_USE_CTS_PROTECT: CTS-to-self protection is required.
 *	This is set if the current BSS requires ERP protection.
 * @IEEE80211_TX_RC_USE_SHORT_PREAMBLE: Use short preamble.
 * @IEEE80211_TX_RC_MCS: HT rate.
 * @IEEE80211_TX_RC_GREEN_FIELD: Indicates whether this rate should be used in
 *	Greenfield mode.
 * @IEEE80211_TX_RC_40_MHZ_WIDTH: Indicates if the Channel Width should be 40 MHz.
 * @IEEE80211_TX_RC_DUP_DATA: The frame should be transmitted on both of the
 *	adjacent 20 MHz channels, if the current channel type is
 *	NL80211_CHAN_HT40MINUS or NL80211_CHAN_HT40PLUS.
 * @IEEE80211_TX_RC_SHORT_GI: Short Guard interval should be used for this rate.
 */
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enum mac80211_rate_control_flags {
	IEEE80211_TX_RC_USE_RTS_CTS		= BIT(0),
	IEEE80211_TX_RC_USE_CTS_PROTECT		= BIT(1),
	IEEE80211_TX_RC_USE_SHORT_PREAMBLE	= BIT(2),

	/* rate index is an MCS rate number instead of an index */
	IEEE80211_TX_RC_MCS			= BIT(3),
	IEEE80211_TX_RC_GREEN_FIELD		= BIT(4),
	IEEE80211_TX_RC_40_MHZ_WIDTH		= BIT(5),
	IEEE80211_TX_RC_DUP_DATA		= BIT(6),
	IEEE80211_TX_RC_SHORT_GI		= BIT(7),
};


/* there are 40 bytes if you don't need the rateset to be kept */
#define IEEE80211_TX_INFO_DRIVER_DATA_SIZE 40
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/* if you do need the rateset, then you have less space */
#define IEEE80211_TX_INFO_RATE_DRIVER_DATA_SIZE 24
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/* maximum number of rate stages */
#define IEEE80211_TX_MAX_RATES	5
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/**
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 * struct ieee80211_tx_rate - rate selection/status
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 *
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 * @idx: rate index to attempt to send with
 * @flags: rate control flags (&enum mac80211_rate_control_flags)
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 * @count: number of tries in this rate before going to the next rate
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 *
 * A value of -1 for @idx indicates an invalid rate and, if used
 * in an array of retry rates, that no more rates should be tried.
 *
 * When used for transmit status reporting, the driver should
 * always report the rate along with the flags it used.
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 */
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struct ieee80211_tx_rate {
	s8 idx;
	u8 count;
	u8 flags;
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} __attribute__((packed));
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/**
 * struct ieee80211_tx_info - skb transmit information
 *
 * This structure is placed in skb->cb for three uses:
 *  (1) mac80211 TX control - mac80211 tells the driver what to do
 *  (2) driver internal use (if applicable)
 *  (3) TX status information - driver tells mac80211 what happened
 *
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 * The TX control's sta pointer is only valid during the ->tx call,
 * it may be NULL.
 *
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 * @flags: transmit info flags, defined above
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 * @band: the band to transmit on (use for checking for races)
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 * @antenna_sel_tx: antenna to use, 0 for automatic diversity
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 * @pad: padding, ignore
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 * @control: union for control data
 * @status: union for status data
 * @driver_data: array of driver_data pointers
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 * @ampdu_ack_len: number of aggregated frames.
 * 	relevant only if IEEE80211_TX_STATUS_AMPDU was set.
 * @ampdu_ack_map: block ack bit map for the aggregation.
 * 	relevant only if IEEE80211_TX_STATUS_AMPDU was set.
 * @ack_signal: signal strength of the ACK frame
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 */
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struct ieee80211_tx_info {
	/* common information */
	u32 flags;
	u8 band;
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	u8 antenna_sel_tx;
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	/* 2 byte hole */
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	u8 pad[2];
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	union {
		struct {
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			union {
				/* rate control */
				struct {
					struct ieee80211_tx_rate rates[
						IEEE80211_TX_MAX_RATES];
					s8 rts_cts_rate_idx;
				};
				/* only needed before rate control */
				unsigned long jiffies;
			};
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			/* NB: vif can be NULL for injected frames */
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			struct ieee80211_vif *vif;
			struct ieee80211_key_conf *hw_key;
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			struct ieee80211_sta *sta;
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		} control;
		struct {
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			struct ieee80211_tx_rate rates[IEEE80211_TX_MAX_RATES];
			u8 ampdu_ack_len;
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			u64 ampdu_ack_map;
			int ack_signal;
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			/* 8 bytes free */
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		} status;
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		struct {
			struct ieee80211_tx_rate driver_rates[
				IEEE80211_TX_MAX_RATES];
			void *rate_driver_data[
				IEEE80211_TX_INFO_RATE_DRIVER_DATA_SIZE / sizeof(void *)];
		};
		void *driver_data[
			IEEE80211_TX_INFO_DRIVER_DATA_SIZE / sizeof(void *)];
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	};
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};

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static inline struct ieee80211_tx_info *IEEE80211_SKB_CB(struct sk_buff *skb)
{
	return (struct ieee80211_tx_info *)skb->cb;
}
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/**
 * ieee80211_tx_info_clear_status - clear TX status
 *
 * @info: The &struct ieee80211_tx_info to be cleared.
 *
 * When the driver passes an skb back to mac80211, it must report
 * a number of things in TX status. This function clears everything
 * in the TX status but the rate control information (it does clear
 * the count since you need to fill that in anyway).
 *
 * NOTE: You can only use this function if you do NOT use
 *	 info->driver_data! Use info->rate_driver_data
 *	 instead if you need only the less space that allows.
 */
static inline void
ieee80211_tx_info_clear_status(struct ieee80211_tx_info *info)
{
	int i;

	BUILD_BUG_ON(offsetof(struct ieee80211_tx_info, status.rates) !=
		     offsetof(struct ieee80211_tx_info, control.rates));
	BUILD_BUG_ON(offsetof(struct ieee80211_tx_info, status.rates) !=
		     offsetof(struct ieee80211_tx_info, driver_rates));
	BUILD_BUG_ON(offsetof(struct ieee80211_tx_info, status.rates) != 8);
	/* clear the rate counts */
	for (i = 0; i < IEEE80211_TX_MAX_RATES; i++)
		info->status.rates[i].count = 0;

	BUILD_BUG_ON(
	    offsetof(struct ieee80211_tx_info, status.ampdu_ack_len) != 23);
	memset(&info->status.ampdu_ack_len, 0,
	       sizeof(struct ieee80211_tx_info) -
	       offsetof(struct ieee80211_tx_info, status.ampdu_ack_len));
}

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/**
 * enum mac80211_rx_flags - receive flags
 *
 * These flags are used with the @flag member of &struct ieee80211_rx_status.
 * @RX_FLAG_MMIC_ERROR: Michael MIC error was reported on this frame.
 *	Use together with %RX_FLAG_MMIC_STRIPPED.
 * @RX_FLAG_DECRYPTED: This frame was decrypted in hardware.
 * @RX_FLAG_RADIOTAP: This frame starts with a radiotap header.
 * @RX_FLAG_MMIC_STRIPPED: the Michael MIC is stripped off this frame,
 *	verification has been done by the hardware.
 * @RX_FLAG_IV_STRIPPED: The IV/ICV are stripped from this frame.
 *	If this flag is set, the stack cannot do any replay detection
 *	hence the driver or hardware will have to do that.
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 * @RX_FLAG_FAILED_FCS_CRC: Set this flag if the FCS check failed on
 *	the frame.
 * @RX_FLAG_FAILED_PLCP_CRC: Set this flag if the PCLP check failed on
 *	the frame.
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 * @RX_FLAG_TSFT: The timestamp passed in the RX status (@mactime field)
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 *	is valid. This is useful in monitor mode and necessary for beacon frames
 *	to enable IBSS merging.
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 * @RX_FLAG_SHORTPRE: Short preamble was used for this frame
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 * @RX_FLAG_HT: HT MCS was used and rate_idx is MCS index
 * @RX_FLAG_40MHZ: HT40 (40 MHz) was used
 * @RX_FLAG_SHORT_GI: Short guard interval was used
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 */
enum mac80211_rx_flags {
	RX_FLAG_MMIC_ERROR	= 1<<0,
	RX_FLAG_DECRYPTED	= 1<<1,
	RX_FLAG_RADIOTAP	= 1<<2,
	RX_FLAG_MMIC_STRIPPED	= 1<<3,
	RX_FLAG_IV_STRIPPED	= 1<<4,
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	RX_FLAG_FAILED_FCS_CRC	= 1<<5,
	RX_FLAG_FAILED_PLCP_CRC = 1<<6,
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	RX_FLAG_TSFT		= 1<<7,
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	RX_FLAG_SHORTPRE	= 1<<8,
	RX_FLAG_HT		= 1<<9,
	RX_FLAG_40MHZ		= 1<<10,
	RX_FLAG_SHORT_GI	= 1<<11,
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};

/**
 * struct ieee80211_rx_status - receive status
 *
 * The low-level driver should provide this information (the subset
 * supported by hardware) to the 802.11 code with each received
 * frame.
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 *
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 * @mactime: value in microseconds of the 64-bit Time Synchronization Function
 * 	(TSF) timer when the first data symbol (MPDU) arrived at the hardware.
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 * @band: the active band when this frame was received
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 * @freq: frequency the radio was tuned to when receiving this frame, in MHz
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 * @signal: signal strength when receiving this frame, either in dBm, in dB or
 *	unspecified depending on the hardware capabilities flags
 *	@IEEE80211_HW_SIGNAL_*
 * @noise: noise when receiving this frame, in dBm.
 * @qual: overall signal quality indication, in percent (0-100).
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 * @antenna: antenna used
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 * @rate_idx: index of data rate into band's supported rates or MCS index if
 *	HT rates are use (RX_FLAG_HT)
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 * @flag: %RX_FLAG_*
 */
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struct ieee80211_rx_status {
	u64 mactime;
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	enum ieee80211_band band;
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	int freq;
	int signal;
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	int noise;
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	int qual;
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	int antenna;
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	int rate_idx;
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	int flag;
};

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/**
 * enum ieee80211_conf_flags - configuration flags
 *
 * Flags to define PHY configuration options
 *
 * @IEEE80211_CONF_RADIOTAP: add radiotap header at receive time (if supported)
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 * @IEEE80211_CONF_PS: Enable 802.11 power save mode (managed mode only)
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 * @IEEE80211_CONF_IDLE: The device is running, but idle; if the flag is set
 *	the driver should be prepared to handle configuration requests but
 *	may turn the device off as much as possible. Typically, this flag will
 *	be set when an interface is set UP but not associated or scanning, but
 *	it can also be unset in that case when monitor interfaces are active.
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 */
enum ieee80211_conf_flags {
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	IEEE80211_CONF_RADIOTAP		= (1<<0),
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	IEEE80211_CONF_PS		= (1<<1),
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	IEEE80211_CONF_IDLE		= (1<<2),
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};
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/**
 * enum ieee80211_conf_changed - denotes which configuration changed
 *
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 * @_IEEE80211_CONF_CHANGE_RADIO_ENABLED: DEPRECATED
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 * @IEEE80211_CONF_CHANGE_LISTEN_INTERVAL: the listen interval changed
 * @IEEE80211_CONF_CHANGE_RADIOTAP: the radiotap flag changed
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 * @IEEE80211_CONF_CHANGE_PS: the PS flag or dynamic PS timeout changed
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 * @IEEE80211_CONF_CHANGE_POWER: the TX power changed
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 * @IEEE80211_CONF_CHANGE_CHANNEL: the channel/channel_type changed
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 * @IEEE80211_CONF_CHANGE_RETRY_LIMITS: retry limits changed
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 * @IEEE80211_CONF_CHANGE_IDLE: Idle flag changed
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 */
enum ieee80211_conf_changed {
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	_IEEE80211_CONF_CHANGE_RADIO_ENABLED	= BIT(0),
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	IEEE80211_CONF_CHANGE_LISTEN_INTERVAL	= BIT(2),
	IEEE80211_CONF_CHANGE_RADIOTAP		= BIT(3),
	IEEE80211_CONF_CHANGE_PS		= BIT(4),
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	IEEE80211_CONF_CHANGE_POWER		= BIT(5),
	IEEE80211_CONF_CHANGE_CHANNEL		= BIT(6),
	IEEE80211_CONF_CHANGE_RETRY_LIMITS	= BIT(7),
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	IEEE80211_CONF_CHANGE_IDLE		= BIT(8),
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};

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static inline __deprecated enum ieee80211_conf_changed
__IEEE80211_CONF_CHANGE_RADIO_ENABLED(void)
{
	return _IEEE80211_CONF_CHANGE_RADIO_ENABLED;
}
#define IEEE80211_CONF_CHANGE_RADIO_ENABLED \
	__IEEE80211_CONF_CHANGE_RADIO_ENABLED()

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/**
 * struct ieee80211_conf - configuration of the device
 *
 * This struct indicates how the driver shall configure the hardware.
 *
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 * @flags: configuration flags defined above
 *
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 * @radio_enabled: when zero, driver is required to switch off the radio.
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 * @beacon_int: DEPRECATED, DO NOT USE
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 *
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 * @listen_interval: listen interval in units of beacon interval
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 * @max_sleep_period: the maximum number of beacon intervals to sleep for
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 *	before checking the beacon for a TIM bit (managed mode only); this
 *	value will be only achievable between DTIM frames, the hardware
 *	needs to check for the multicast traffic bit in DTIM beacons.
 *	This variable is valid only when the CONF_PS flag is set.
 * @dynamic_ps_timeout: The dynamic powersave timeout (in ms), see the
 *	powersave documentation below. This variable is valid only when
 *	the CONF_PS flag is set.
 *
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 * @power_level: requested transmit power (in dBm)
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 *
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 * @channel: the channel to tune to
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 * @channel_type: the channel (HT) type
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 *
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 * @long_frame_max_tx_count: Maximum number of transmissions for a "long" frame
 *    (a frame not RTS protected), called "dot11LongRetryLimit" in 802.11,
 *    but actually means the number of transmissions not the number of retries
 * @short_frame_max_tx_count: Maximum number of transmissions for a "short"
 *    frame, called "dot11ShortRetryLimit" in 802.11, but actually means the
 *    number of transmissions not the number of retries
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 */
struct ieee80211_conf {
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	int __deprecated beacon_int;
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	u32 flags;
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	int power_level, dynamic_ps_timeout;
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	int max_sleep_period;
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	u16 listen_interval;
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	bool __deprecated radio_enabled;
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	u8 long_frame_max_tx_count, short_frame_max_tx_count;

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	struct ieee80211_channel *channel;
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	enum nl80211_channel_type channel_type;
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};

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/**
 * struct ieee80211_vif - per-interface data
 *
 * Data in this structure is continually present for driver
 * use during the life of a virtual interface.
 *
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 * @type: type of this virtual interface
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 * @bss_conf: BSS configuration for this interface, either our own
 *	or the BSS we're associated to
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 * @drv_priv: data area for driver use, will always be aligned to
 *	sizeof(void *).
 */
struct ieee80211_vif {
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	enum nl80211_iftype type;
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	struct ieee80211_bss_conf bss_conf;
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	/* must be last */
	u8 drv_priv[0] __attribute__((__aligned__(sizeof(void *))));
};

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static inline bool ieee80211_vif_is_mesh(struct ieee80211_vif *vif)
{
#ifdef CONFIG_MAC80211_MESH
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	return vif->type == NL80211_IFTYPE_MESH_POINT;
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#endif
	return false;
}

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/**
 * struct ieee80211_if_init_conf - initial configuration of an interface
 *
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 * @vif: pointer to a driver-use per-interface structure. The pointer
 *	itself is also used for various functions including
 *	ieee80211_beacon_get() and ieee80211_get_buffered_bc().
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 * @type: one of &enum nl80211_iftype constants. Determines the type of
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 *	added/removed interface.
 * @mac_addr: pointer to MAC address of the interface. This pointer is valid
 *	until the interface is removed (i.e. it cannot be used after
 *	remove_interface() callback was called for this interface).
 *
 * This structure is used in add_interface() and remove_interface()
 * callbacks of &struct ieee80211_hw.
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 *
 * When you allow multiple interfaces to be added to your PHY, take care
 * that the hardware can actually handle multiple MAC addresses. However,
 * also take care that when there's no interface left with mac_addr != %NULL
 * you remove the MAC address from the device to avoid acknowledging packets
 * in pure monitor mode.
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 */
struct ieee80211_if_init_conf {
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	enum nl80211_iftype type;
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	struct ieee80211_vif *vif;
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	void *mac_addr;
};

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/**
 * enum ieee80211_key_alg - key algorithm
 * @ALG_WEP: WEP40 or WEP104
 * @ALG_TKIP: TKIP
 * @ALG_CCMP: CCMP (AES)
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 * @ALG_AES_CMAC: AES-128-CMAC
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 */
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enum ieee80211_key_alg {
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	ALG_WEP,
	ALG_TKIP,
	ALG_CCMP,
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	ALG_AES_CMAC,
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};
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/**
 * enum ieee80211_key_flags - key flags
 *
 * These flags are used for communication about keys between the driver
 * and mac80211, with the @flags parameter of &struct ieee80211_key_conf.
 *
 * @IEEE80211_KEY_FLAG_WMM_STA: Set by mac80211, this flag indicates
 *	that the STA this key will be used with could be using QoS.
 * @IEEE80211_KEY_FLAG_GENERATE_IV: This flag should be set by the
 *	driver to indicate that it requires IV generation for this
 *	particular key.
 * @IEEE80211_KEY_FLAG_GENERATE_MMIC: This flag should be set by
 *	the driver for a TKIP key if it requires Michael MIC
 *	generation in software.
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 * @IEEE80211_KEY_FLAG_PAIRWISE: Set by mac80211, this flag indicates
 *	that the key is pairwise rather then a shared key.
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 * @IEEE80211_KEY_FLAG_SW_MGMT: This flag should be set by the driver for a
 *	CCMP key if it requires CCMP encryption of management frames (MFP) to
 *	be done in software.
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 */
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enum ieee80211_key_flags {
	IEEE80211_KEY_FLAG_WMM_STA	= 1<<0,
	IEEE80211_KEY_FLAG_GENERATE_IV	= 1<<1,
	IEEE80211_KEY_FLAG_GENERATE_MMIC= 1<<2,
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	IEEE80211_KEY_FLAG_PAIRWISE	= 1<<3,
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	IEEE80211_KEY_FLAG_SW_MGMT	= 1<<4,
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};
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/**
 * struct ieee80211_key_conf - key information
 *
 * This key information is given by mac80211 to the driver by
 * the set_key() callback in &struct ieee80211_ops.
 *
 * @hw_key_idx: To be set by the driver, this is the key index the driver
 *	wants to be given when a frame is transmitted and needs to be
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 *	encrypted in hardware.
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 * @alg: The key algorithm.
 * @flags: key flags, see &enum ieee80211_key_flags.
 * @keyidx: the key index (0-3)
 * @keylen: key material length
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 * @key: key material. For ALG_TKIP the key is encoded as a 256-bit (32 byte)
 * 	data block:
 * 	- Temporal Encryption Key (128 bits)
 * 	- Temporal Authenticator Tx MIC Key (64 bits)
 * 	- Temporal Authenticator Rx MIC Key (64 bits)
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 * @icv_len: The ICV length for this key type
 * @iv_len: The IV length for this key type
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 */
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struct ieee80211_key_conf {
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	enum ieee80211_key_alg alg;
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	u8 icv_len;
	u8 iv_len;
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	u8 hw_key_idx;
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	u8 flags;
	s8 keyidx;
	u8 keylen;
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	u8 key[0];
};

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/**
 * enum set_key_cmd - key command
 *
 * Used with the set_key() callback in &struct ieee80211_ops, this
 * indicates whether a key is being removed or added.
 *
 * @SET_KEY: a key is set
 * @DISABLE_KEY: a key must be disabled
 */
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enum set_key_cmd {
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	SET_KEY, DISABLE_KEY,
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};
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/**
 * struct ieee80211_sta - station table entry
 *
 * A station table entry represents a station we are possibly
 * communicating with. Since stations are RCU-managed in
 * mac80211, any ieee80211_sta pointer you get access to must
 * either be protected by rcu_read_lock() explicitly or implicitly,
 * or you must take good care to not use such a pointer after a
 * call to your sta_notify callback that removed it.
 *
 * @addr: MAC address
 * @aid: AID we assigned to the station if we're an AP
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 * @supp_rates: Bitmap of supported rates (per band)
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 * @ht_cap: HT capabilities of this STA; restricted to our own TX capabilities
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 * @drv_priv: data area for driver use, will always be aligned to
 *	sizeof(void *), size is determined in hw information.
 */
struct ieee80211_sta {
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	u32 supp_rates[IEEE80211_NUM_BANDS];
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	u8 addr[ETH_ALEN];
	u16 aid;
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	struct ieee80211_sta_ht_cap ht_cap;
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	/* must be last */
	u8 drv_priv[0] __attribute__((__aligned__(sizeof(void *))));
};

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/**
 * enum sta_notify_cmd - sta notify command
 *
 * Used with the sta_notify() callback in &struct ieee80211_ops, this
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 * indicates addition and removal of a station to station table,
 * or if a associated station made a power state transition.
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 *
 * @STA_NOTIFY_ADD: a station was added to the station table
 * @STA_NOTIFY_REMOVE: a station being removed from the station table
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 * @STA_NOTIFY_SLEEP: a station is now sleeping
 * @STA_NOTIFY_AWAKE: a sleeping station woke up
 */
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enum sta_notify_cmd {
	STA_NOTIFY_ADD, STA_NOTIFY_REMOVE,
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	STA_NOTIFY_SLEEP, STA_NOTIFY_AWAKE,
};

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/**
 * enum ieee80211_tkip_key_type - get tkip key
 *
 * Used by drivers which need to get a tkip key for skb. Some drivers need a
 * phase 1 key, others need a phase 2 key. A single function allows the driver
 * to get the key, this enum indicates what type of key is required.
 *
 * @IEEE80211_TKIP_P1_KEY: the driver needs a phase 1 key
 * @IEEE80211_TKIP_P2_KEY: the driver needs a phase 2 key
 */
enum ieee80211_tkip_key_type {
	IEEE80211_TKIP_P1_KEY,
	IEEE80211_TKIP_P2_KEY,
};

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/**
 * enum ieee80211_hw_flags - hardware flags
 *
 * 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 doesn't need setting
 * any particular flags. There are some exceptions to this rule,
 * however, so you are advised to review these flags carefully.
 *
 * @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
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 *	the driver can fetch them with ieee80211_get_buffered_bc().
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 *
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 * @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.
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 *
 * @IEEE80211_HW_SIGNAL_UNSPEC:
 *	Hardware can provide signal values but we don't 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_NOISE_DBM:
 *	Hardware can provide noise (radio interference) values in units dBm,
 *      decibel difference from one milliwatt.
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 *
 * @IEEE80211_HW_SPECTRUM_MGMT:
 * 	Hardware supports spectrum management defined in 802.11h
 * 	Measurement, Channel Switch, Quieting, TPC
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 *
 * @IEEE80211_HW_AMPDU_AGGREGATION:
 *	Hardware supports 11n A-MPDU aggregation.
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 *
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 * @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.
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 *
 * @IEEE80211_HW_MFP_CAPABLE:
 *	Hardware supports management frame protection (MFP, IEEE 802.11w).
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 *
 * @IEEE80211_HW_BEACON_FILTER:
 *	Hardware supports dropping of irrelevant beacon frames to
 *	avoid waking up cpu.
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 */
enum ieee80211_hw_flags {
	IEEE80211_HW_RX_INCLUDES_FCS			= 1<<1,
	IEEE80211_HW_HOST_BROADCAST_PS_BUFFERING	= 1<<2,
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	IEEE80211_HW_2GHZ_SHORT_SLOT_INCAPABLE		= 1<<3,
	IEEE80211_HW_2GHZ_SHORT_PREAMBLE_INCAPABLE	= 1<<4,
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	IEEE80211_HW_SIGNAL_UNSPEC			= 1<<5,
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	IEEE80211_HW_SIGNAL_DBM				= 1<<6,
	IEEE80211_HW_NOISE_DBM				= 1<<7,
	IEEE80211_HW_SPECTRUM_MGMT			= 1<<8,
	IEEE80211_HW_AMPDU_AGGREGATION			= 1<<9,
	IEEE80211_HW_SUPPORTS_PS			= 1<<10,
	IEEE80211_HW_PS_NULLFUNC_STACK			= 1<<11,
	IEEE80211_HW_SUPPORTS_DYNAMIC_PS		= 1<<12,
	IEEE80211_HW_MFP_CAPABLE			= 1<<13,
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	IEEE80211_HW_BEACON_FILTER			= 1<<14,
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};

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/**
 * struct ieee80211_hw - hardware information and state
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 *
 * This structure contains the configuration and hardware
 * information for an 802.11 PHY.
 *
 * @wiphy: This points to the &struct wiphy allocated for this
 *	802.11 PHY. You must fill in the @perm_addr and @dev
 *	members of this structure using SET_IEEE80211_DEV()
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 *	and SET_IEEE80211_PERM_ADDR(). Additionally, all supported
 *	bands (with channels, bitrates) are registered here.
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 *
 * @conf: &struct ieee80211_conf, device configuration, don't use.
 *
 * @workqueue: single threaded workqueue available for driver use,
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 *	allocated by mac80211 on registration and flushed when an
 *	interface is removed.
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 *	NOTICE: All work performed on this workqueue must not
 *	acquire the RTNL lock.
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 *
 * @priv: pointer to private area that was allocated for driver use
 *	along with this structure.
 *
 * @flags: hardware flags, see &enum ieee80211_hw_flags.
 *
 * @extra_tx_headroom: headroom to reserve in each transmit skb
 *	for use by the driver (e.g. for transmit headers.)
 *
 * @channel_change_time: time (in microseconds) it takes to change channels.
 *
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 * @max_signal: Maximum value for signal (rssi) in RX information, used
 *     only when @IEEE80211_HW_SIGNAL_UNSPEC or @IEEE80211_HW_SIGNAL_DB
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 *
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 * @max_listen_interval: max listen interval in units of beacon interval
 *     that HW supports
 *
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 * @queues: number of available hardware transmit queues for
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 *	data packets. WMM/QoS requires at least four, these
 *	queues need to have configurable access parameters.
 *
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 * @rate_control_algorithm: rate control algorithm for this hardware.
 *	If unset (NULL), the default algorithm will be used. Must be
 *	set before calling ieee80211_register_hw().
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 *
 * @vif_data_size: size (in bytes) of the drv_priv data area
 *	within &struct ieee80211_vif.
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 * @sta_data_size: size (in bytes) of the drv_priv data area
 *	within &struct ieee80211_sta.
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 *
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 * @max_rates: maximum number of alternate rate retry stages
 * @max_rate_tries: maximum number of tries for each stage
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 */
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struct ieee80211_hw {
	struct ieee80211_conf conf;
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	struct wiphy *wiphy;
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	struct workqueue_struct *workqueue;
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	const char *rate_control_algorithm;
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	void *priv;
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	u32 flags;
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	unsigned int extra_tx_headroom;
	int channel_change_time;
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	int vif_data_size;
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	int sta_data_size;
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	u16 queues;
	u16 max_listen_interval;
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	s8 max_signal;
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	u8 max_rates;
	u8 max_rate_tries;
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};

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/**
 * wiphy_to_ieee80211_hw - return a mac80211 driver hw struct from a wiphy
 *
 * @wiphy: the &struct wiphy which we want to query
 *
 * mac80211 drivers can use this to get to their respective
 * &struct ieee80211_hw. Drivers wishing to get to their own private
 * structure can then access it via hw->priv. Note that mac802111 drivers should
 * not use wiphy_priv() to try to get their private driver structure as this
 * is already used internally by mac80211.
 */
struct ieee80211_hw *wiphy_to_ieee80211_hw(struct wiphy *wiphy);

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/**
 * SET_IEEE80211_DEV - set device for 802.11 hardware
 *
 * @hw: the &struct ieee80211_hw to set the device for
 * @dev: the &struct device of this 802.11 device
 */
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static inline void SET_IEEE80211_DEV(struct ieee80211_hw *hw, struct device *dev)
{
	set_wiphy_dev(hw->wiphy, dev);
}

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/**
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 * SET_IEEE80211_PERM_ADDR - set the permanent MAC address for 802.11 hardware
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 *
 * @hw: the &struct ieee80211_hw to set the MAC address for
 * @addr: the address to set
 */
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static inline void SET_IEEE80211_PERM_ADDR(struct ieee80211_hw *hw, u8 *addr)
{
	memcpy(hw->wiphy->perm_addr, addr, ETH_ALEN);
}

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static inline struct ieee80211_rate *
ieee80211_get_tx_rate(const struct ieee80211_hw *hw,
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		      const struct ieee80211_tx_info *c)
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{
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	if (WARN_ON(c->control.rates[0].idx < 0))
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		return NULL;
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	return &hw->wiphy->bands[c->band]->bitrates[c->control.rates[0].idx];
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}

static inline struct ieee80211_rate *
ieee80211_get_rts_cts_rate(const struct ieee80211_hw *hw,
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			   const struct ieee80211_tx_info *c)
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{
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	if (c->control.rts_cts_rate_idx < 0)
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		return NULL;
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	return &hw->wiphy->bands[c->band]->bitrates[c->control.rts_cts_rate_idx];
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}

static inline struct ieee80211_rate *
ieee80211_get_alt_retry_rate(const struct ieee80211_hw *hw,
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			     const struct ieee80211_tx_info *c, int idx)
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{
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	if (c->control.rates[idx + 1].idx < 0)
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		return NULL;
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	return &hw->wiphy->bands[c->band]->bitrates[c->control.rates[idx + 1].idx];
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}

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/**
 * DOC: Hardware crypto acceleration
 *
 * mac80211 is capable of taking advantage of many hardware
 * acceleration designs for encryption and decryption operations.
 *
 * The set_key() callback in the &struct ieee80211_ops for a given
 * device is called to enable hardware acceleration of encryption and
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 * decryption. The callback takes a @sta parameter that will be NULL
 * for default keys or keys used for transmission only, or point to
 * the station information for the peer for individual keys.
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 * Multiple transmission keys with the same key index may be used when
 * VLANs are configured for an access point.
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 *
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 * When transmitting, the TX control data will use the @hw_key_idx
 * selected by the driver by modifying the &struct ieee80211_key_conf
 * pointed to by the @key parameter to the set_key() function.
 *
 * The set_key() call for the %SET_KEY command should return 0 if
 * the key is now in use, -%EOPNOTSUPP or -%ENOSPC if it couldn't be
 * added; if you return 0 then hw_key_idx must be assigned to the
 * hardware key index, you are free to use the full u8 range.
 *
 * When the cmd is %DISABLE_KEY then it must succeed.
 *
 * Note that it is permissible to not decrypt a frame even if a key
 * for it has been uploaded to hardware, the stack will not make any
 * decision based on whether a key has been uploaded or not but rather
 * based on the receive flags.
 *
 * The &struct ieee80211_key_conf structure pointed to by the @key
 * parameter is guaranteed to be valid until another call to set_key()
 * removes it, but it can only be used as a cookie to differentiate
 * keys.
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 *
 * In TKIP some HW need to be provided a phase 1 key, for RX decryption
 * acceleration (i.e. iwlwifi). Those drivers should provide update_tkip_key
 * handler.
 * The update_tkip_key() call updates the driver with the new phase 1 key.
 * This happens everytime the iv16 wraps around (every 65536 packets). The
 * set_key() call will happen only once for each key (unless the AP did
 * rekeying), it will not include a valid phase 1 key. The valid phase 1 key is