From 75a5f0ccfdbc0151ee40bb742f7b5c8eba493c0e Mon Sep 17 00:00:00 2001 From: Johannes Berg Date: Tue, 18 Sep 2007 17:29:20 -0400 Subject: [PATCH] [PATCH] mac80211: document a lot more This patch adds a lot more documentation (in kernel-doc format) to include/net/mac80211.h Signed-off-by: Johannes Berg Signed-off-by: Michael Wu Signed-off-by: John W. Linville --- include/net/mac80211.h | 792 ++++++++++++++++++++++++++--------------- 1 file changed, 499 insertions(+), 293 deletions(-) diff --git a/include/net/mac80211.h b/include/net/mac80211.h index c5554ad87a17..d2cf734402e3 100644 --- a/include/net/mac80211.h +++ b/include/net/mac80211.h @@ -22,29 +22,51 @@ #include #include -/* Note! Only ieee80211_tx_status_irqsafe() and ieee80211_rx_irqsafe() can be +/** + * 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 * 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 - * IEEE 802.11 code call after this, e.g., from a scheduled tasklet (in - * software interrupt context). + * IEEE 802.11 code call after this, e.g. from a scheduled workqueue function. */ -/* - * Frame format used when passing frame between low-level hardware drivers - * and IEEE 802.11 driver the same as used in the wireless media, i.e., - * buffers start with IEEE 802.11 header and include the same octets that - * are sent over air. - * - * If hardware uses IEEE 802.3 headers (and perform 802.3 <-> 802.11 - * conversion in firmware), upper layer 802.11 code needs to be changed to - * support this. - * - * If the receive frame format is not the same as the real frame sent - * on the wireless media (e.g., due to padding etc.), upper layer 802.11 code - * could be updated to provide support for such format assuming this would - * optimize the performance, e.g., by removing need to re-allocation and - * copying of the data. +/** + * 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. */ #define IEEE80211_CHAN_W_SCAN 0x00000001 @@ -480,7 +502,7 @@ enum ieee80211_if_types { */ struct ieee80211_if_init_conf { int if_id; - int type; + enum ieee80211_if_types type; void *mac_addr; }; @@ -645,351 +667,426 @@ enum ieee80211_hw_flags { /** * struct ieee80211_hw - hardware information and state - * TODO: move documentation into kernel-doc format + * + * 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() + * and SET_IEEE80211_PERM_ADDR(). + * + * @conf: &struct ieee80211_conf, device configuration, don't use. + * + * @workqueue: single threaded workqueue available for driver use, + * allocated by mac80211 on registration and flushed on + * unregistration. + * + * @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. + * + * @max_rssi: Maximum value for ssi in RX information, use + * negative numbers for dBm and 0 to indicate no support. + * + * @max_signal: like @max_rssi, but for the signal value. + * + * @max_noise: like @max_rssi, but for the noise value. + * + * @queues: number of available hardware transmit queues for + * data packets. WMM/QoS requires at least four. */ struct ieee80211_hw { - /* points to the cfg80211 wiphy for this piece. Note - * that you must fill in the perm_addr and dev fields - * of this structure, use the macros provided below. */ - struct wiphy *wiphy; - - /* assigned by mac80211, don't write */ struct ieee80211_conf conf; - - /* Single thread workqueue available for driver use - * Allocated by mac80211 on registration */ + struct wiphy *wiphy; struct workqueue_struct *workqueue; - - /* Pointer to the private area that was - * allocated with this struct for you. */ void *priv; - - /* The rest is information about your hardware */ - - u32 flags; /* hardware flags defined above */ - - /* Set to the size of a needed device specific skb headroom for TX skbs. */ + u32 flags; unsigned int extra_tx_headroom; - - /* This is the time in us to change channels - */ int channel_change_time; - /* Maximum values for various statistics. - * Leave at 0 to indicate no support. Use negative numbers for dBm. */ + u8 queues; s8 max_rssi; s8 max_signal; s8 max_noise; - - /* Number of available hardware TX queues for data packets. - * WMM requires at least four queues. */ - int queues; }; +/** + * 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 + */ static inline void SET_IEEE80211_DEV(struct ieee80211_hw *hw, struct device *dev) { set_wiphy_dev(hw->wiphy, dev); } +/** + * SET_IEEE80211_PERM_ADDR - set the permanenet MAC address for 802.11 hardware + * + * @hw: the &struct ieee80211_hw to set the MAC address for + * @addr: the address to set + */ static inline void SET_IEEE80211_PERM_ADDR(struct ieee80211_hw *hw, u8 *addr) { memcpy(hw->wiphy->perm_addr, addr, ETH_ALEN); } -/* - * flags for change_filter_flags() +/** + * 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 + * decryption. The callback takes an @address parameter that will be + * the broadcast address for default keys, the other station's hardware + * address for individual keys or the zero address for keys that will + * be used only for transmission. + * Multiple transmission keys with the same key index may be used when + * VLANs are configured for an access point. * - * Note that e.g. if PROMISC_IN_BSS is unset then - * you should still do MAC address filtering if - * possible even if OTHER_BSS is set to indicate - * no BSSID filtering should be done. + * The @local_address parameter will always be set to our own address, + * this is only relevant if you support multiple local addresses. + * + * 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. */ -/* - * promiscuous mode within your BSS, - * think of the BSS as your network segment and then this corresponds - * to the regular ethernet device promiscuous mode + +/** + * DOC: Frame filtering + * + * mac80211 requires to see many management frames for proper + * operation, and users may want to see many more frames when + * in monitor mode. However, for best CPU usage and power consumption, + * having as few frames as possible percolate through the stack is + * desirable. Hence, the hardware should filter as much as possible. + * + * To achieve this, mac80211 uses filter flags (see below) to tell + * the driver's configure_filter() function which frames should be + * passed to mac80211 and which should be filtered out. + * + * The configure_filter() callback is invoked with the parameters + * @mc_count and @mc_list for the combined multicast address list + * of all virtual interfaces, @changed_flags telling which flags + * were changed and @total_flags with the new flag states. + * + * If your device has no multicast address filters your driver will + * need to check both the %FIF_ALLMULTI flag and the @mc_count + * parameter to see whether multicast frames should be accepted + * or dropped. + * + * All unsupported flags in @total_flags must be cleared, i.e. you + * should clear all bits except those you honoured. */ -#define FIF_PROMISC_IN_BSS 0x01 -/* show all multicast frames */ -#define FIF_ALLMULTI 0x02 -/* show frames with failed FCS, but set RX_FLAG_FAILED_FCS_CRC for them */ -#define FIF_FCSFAIL 0x04 -/* show frames with failed PLCP CRC, but set RX_FLAG_FAILED_PLCP_CRC for them */ -#define FIF_PLCPFAIL 0x08 -/* - * This flag is set during scanning to indicate to the hardware - * that it should not filter beacons or probe responses by BSSID. + +/** + * enum ieee80211_filter_flags - hardware filter flags + * + * These flags determine what the filter in hardware should be + * programmed to let through and what should not be passed to the + * stack. It is always safe to pass more frames than requested, + * but this has negative impact on power consumption. + * + * @FIF_PROMISC_IN_BSS: promiscuous mode within your BSS, + * think of the BSS as your network segment and then this corresponds + * to the regular ethernet device promiscuous mode. + * + * @FIF_ALLMULTI: pass all multicast frames, this is used if requested + * by the user or if the hardware is not capable of filtering by + * multicast address. + * + * @FIF_FCSFAIL: pass frames with failed FCS (but you need to set the + * %RX_FLAG_FAILED_FCS_CRC for them) + * + * @FIF_PLCPFAIL: pass frames with failed PLCP CRC (but you need to set + * the %RX_FLAG_FAILED_PLCP_CRC for them + * + * @FIF_BCN_PRBRESP_PROMISC: This flag is set during scanning to indicate + * to the hardware that it should not filter beacons or probe responses + * by BSSID. Filtering them can greatly reduce the amount of processing + * mac80211 needs to do and the amount of CPU wakeups, so you should + * honour this flag if possible. + * + * @FIF_CONTROL: pass control frames, if PROMISC_IN_BSS is not set then + * only those addressed to this station + * + * @FIF_OTHER_BSS: pass frames destined to other BSSes */ -#define FIF_BCN_PRBRESP_PROMISC 0x10 -/* - * show control frames, if PROMISC_IN_BSS is not set then - * only those addressed to this station +enum ieee80211_filter_flags { + FIF_PROMISC_IN_BSS = 1<<0, + FIF_ALLMULTI = 1<<1, + FIF_FCSFAIL = 1<<2, + FIF_PLCPFAIL = 1<<3, + FIF_BCN_PRBRESP_PROMISC = 1<<4, + FIF_CONTROL = 1<<5, + FIF_OTHER_BSS = 1<<6, +}; + +/** + * enum ieee80211_erp_change_flags - erp change flags + * + * These flags are used with the erp_ie_changed() callback in + * &struct ieee80211_ops to indicate which parameter(s) changed. + * @IEEE80211_ERP_CHANGE_PROTECTION: protection changed + * @IEEE80211_ERP_CHANGE_PREAMBLE: barker preamble mode changed */ -#define FIF_CONTROL 0x20 -/* show frames from other BSSes */ -#define FIF_OTHER_BSS 0x40 +enum ieee80211_erp_change_flags { + IEEE80211_ERP_CHANGE_PROTECTION = 1<<0, + IEEE80211_ERP_CHANGE_PREAMBLE = 1<<1, +}; -/* Configuration block used by the low-level driver to tell the 802.11 code - * about supported hardware features and to pass function pointers to callback - * functions. */ + +/** + * struct ieee80211_ops - callbacks from mac80211 to the driver + * + * This structure contains various callbacks that the driver may + * handle or, in some cases, must handle, for example to configure + * the hardware to a new channel or to transmit a frame. + * + * @tx: Handler that 802.11 module calls for each transmitted frame. + * skb contains the buffer starting from the IEEE 802.11 header. + * The low-level driver should send the frame out based on + * configuration in the TX control data. Must be implemented and + * atomic. + * + * @start: Called before the first netdevice attached to the hardware + * is enabled. This should turn on the hardware and must turn on + * frame reception (for possibly enabled monitor interfaces.) + * Returns negative error codes, these may be seen in userspace, + * or zero. + * When the device is started it should not have a MAC address + * to avoid acknowledging frames before a non-monitor device + * is added. + * Must be implemented. + * + * @stop: Called after last netdevice attached to the hardware + * is disabled. This should turn off the hardware (at least + * it must turn off frame reception.) + * May be called right after add_interface if that rejects + * an interface. + * Must be implemented. + * + * @add_interface: Called when a netdevice attached to the hardware is + * enabled. Because it is not called for monitor mode devices, @open + * and @stop must be implemented. + * The driver should perform any initialization it needs before + * the device can be enabled. The initial configuration for the + * interface is given in the conf parameter. + * The callback may refuse to add an interface by returning a + * negative error code (which will be seen in userspace.) + * Must be implemented. + * + * @remove_interface: Notifies a driver that an interface is going down. + * The @stop callback is called after this if it is the last interface + * and no monitor interfaces are present. + * When all interfaces are removed, the MAC address in the hardware + * must be cleared so the device no longer acknowledges packets, + * the mac_addr member of the conf structure is, however, set to the + * MAC address of the device going away. + * Hence, this callback must be implemented. + * + * @config: Handler for configuration requests. IEEE 802.11 code calls this + * function to change hardware configuration, e.g., channel. + * + * @config_interface: Handler for configuration requests related to interfaces + * (e.g. BSSID changes.) + * + * @configure_filter: Configure the device's RX filter. + * See the section "Frame filtering" for more information. + * This callback must be implemented and atomic. + * + * @set_tim: Set TIM bit. If the hardware/firmware takes care of beacon + * generation (that is, %IEEE80211_HW_HOST_GEN_BEACON_TEMPLATE is set) + * mac80211 calls this function when a TIM bit must be set or cleared + * for a given AID. Must be atomic. + * + * @set_key: See the section "Hardware crypto acceleration" + * This callback can sleep, and is only called between add_interface + * and remove_interface calls, i.e. while the interface with the + * given local_address is enabled. + * + * @set_ieee8021x: Enable/disable IEEE 802.1X. This item requests wlan card + * to pass unencrypted EAPOL-Key frames even when encryption is + * configured. If the wlan card does not require such a configuration, + * this function pointer can be set to NULL. + * + * @set_port_auth: Set port authorization state (IEEE 802.1X PAE) to be + * authorized (@authorized=1) or unauthorized (=0). This function can be + * used if the wlan hardware or low-level driver implements PAE. + * mac80211 will filter frames based on authorization state in any case, + * so this function pointer can be NULL if low-level driver does not + * require event notification about port state changes. + * + * @hw_scan: Ask the hardware to service the scan request, no need to start + * the scan state machine in stack. + * + * @get_stats: return low-level statistics + * + * @set_privacy_invoked: For devices that generate their own beacons and probe + * response or association responses this updates the state of privacy_invoked + * returns 0 for success or an error number. + * + * @get_sequence_counter: For devices that have internal sequence counters this + * callback allows mac80211 to access the current value of a counter. + * This callback seems not well-defined, tell us if you need it. + * + * @set_rts_threshold: Configuration of RTS threshold (if device needs it) + * + * @set_frag_threshold: Configuration of fragmentation threshold. Assign this if + * the device does fragmentation by itself; if this method is assigned then + * the stack will not do fragmentation. + * + * @set_retry_limit: Configuration of retry limits (if device needs it) + * + * @sta_table_notification: Number of STAs in STA table notification. Must + * be atomic. + * + * @erp_ie_changed: Handle ERP IE change notifications. Must be atomic. + * + * @conf_tx: Configure TX queue parameters (EDCF (aifs, cw_min, cw_max), + * bursting) for a hardware TX queue. The @queue parameter uses the + * %IEEE80211_TX_QUEUE_* constants. Must be atomic. + * + * @get_tx_stats: Get statistics of the current TX queue status. This is used + * to get number of currently queued packets (queue length), maximum queue + * size (limit), and total number of packets sent using each TX queue + * (count). This information is used for WMM to find out which TX + * queues have room for more packets and by hostapd to provide + * statistics about the current queueing state to external programs. + * + * @get_tsf: Get the current TSF timer value from firmware/hardware. Currently, + * this is only used for IBSS mode debugging and, as such, is not a + * required function. Must be atomic. + * + * @reset_tsf: Reset the TSF timer and allow firmware/hardware to synchronize + * with other STAs in the IBSS. This is only used in IBSS mode. This + * function is optional if the firmware/hardware takes full care of + * TSF synchronization. + * + * @beacon_update: Setup beacon data for IBSS beacons. Unlike access point, + * IBSS uses a fixed beacon frame which is configured using this + * function. This handler is required only for IBSS mode. + * + * @tx_last_beacon: Determine whether the last IBSS beacon was sent by us. + * This is needed only for IBSS mode and the result of this function is + * used to determine whether to reply to Probe Requests. + */ struct ieee80211_ops { - /* Handler that 802.11 module calls for each transmitted frame. - * skb contains the buffer starting from the IEEE 802.11 header. - * The low-level driver should send the frame out based on - * configuration in the TX control data. - * Must be atomic. */ int (*tx)(struct ieee80211_hw *hw, struct sk_buff *skb, struct ieee80211_tx_control *control); - - /* - * Called before the first netdevice attached to the hardware - * is enabled. This should turn on the hardware and must turn on - * frame reception (for possibly enabled monitor interfaces.) - * Returns negative error codes, these may be seen in userspace, - * or zero. - * When the device is started it should not have a MAC address - * to avoid acknowledging frames before a non-monitor device - * is added. - * - * Must be implemented. - */ int (*start)(struct ieee80211_hw *hw); - - /* - * Called after last netdevice attached to the hardware - * is disabled. This should turn off the hardware (at least - * it must turn off frame reception.) - * May be called right after add_interface if that rejects - * an interface. - * - * Must be implemented. - */ void (*stop)(struct ieee80211_hw *hw); - - /* - * Called when a netdevice attached to the hardware is enabled. - * Because it is not called for monitor mode devices, open() - * and stop() must be implemented. - * The driver should perform any initialization it needs before - * the device can be enabled. The initial configuration for the - * interface is given in the conf parameter. - * - * Must be implemented. - */ int (*add_interface)(struct ieee80211_hw *hw, struct ieee80211_if_init_conf *conf); - - /* - * Notifies a driver that an interface is going down. The stop() handler - * is called after this if it is the last interface and no monitor - * interfaces are present. - * When all interfaces are removed, the MAC address in the hardware - * must be cleared so the device no longer acknowledges packets, - * the mac_addr member of the conf structure is, however, set to the - * MAC address of the device going away. - * - * Hence, this callback must be implemented. - */ void (*remove_interface)(struct ieee80211_hw *hw, struct ieee80211_if_init_conf *conf); - - /* Handler for configuration requests. IEEE 802.11 code calls this - * function to change hardware configuration, e.g., channel. */ int (*config)(struct ieee80211_hw *hw, struct ieee80211_conf *conf); - - /* Handler for configuration requests related to interfaces (e.g. - * BSSID). */ int (*config_interface)(struct ieee80211_hw *hw, int if_id, struct ieee80211_if_conf *conf); - - /* - * Configure the device's RX filter. - * - * The multicast address filter must be changed if the hardware flags - * indicate that one is present. - * - * All unsupported flags in 'total_flags' must be cleared, - * clear all bits except those you honoured. - * - * The callback must be implemented and must be atomic. - */ void (*configure_filter)(struct ieee80211_hw *hw, unsigned int changed_flags, unsigned int *total_flags, int mc_count, struct dev_addr_list *mc_list); - - /* Set TIM bit handler. If the hardware/firmware takes care of beacon - * generation, IEEE 802.11 code uses this function to tell the - * low-level to set (or clear if set==0) TIM bit for the given aid. If - * host system is used to generate beacons, this handler is not used - * and low-level driver should set it to NULL. - * Must be atomic. */ int (*set_tim)(struct ieee80211_hw *hw, int aid, int set); - - /* - * Set encryption key. - * - * This is called to enable hardware acceleration of encryption and - * decryption. The address will be the broadcast address for default - * keys, the other station's hardware address for individual keys or - * the zero address for keys that will be used only for transmission. - * - * The local_address parameter will always be set to our own address, - * this is only relevant if you support multiple local addresses. - * - * When transmitting, the TX control data will use the hw_key_idx - * selected by the low-level driver. - * - * 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. - * - * This callback can sleep, and is only called between add_interface - * and remove_interface calls, i.e. while the interface with the - * given local_address is enabled. - * - * The 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. - */ int (*set_key)(struct ieee80211_hw *hw, set_key_cmd cmd, const u8 *local_address, const u8 *address, struct ieee80211_key_conf *key); - - /* Enable/disable IEEE 802.1X. This item requests wlan card to pass - * unencrypted EAPOL-Key frames even when encryption is configured. - * If the wlan card does not require such a configuration, this - * function pointer can be set to NULL. */ int (*set_ieee8021x)(struct ieee80211_hw *hw, int use_ieee8021x); - - /* Set port authorization state (IEEE 802.1X PAE) to be authorized - * (authorized=1) or unauthorized (authorized=0). This function can be - * used if the wlan hardware or low-level driver implements PAE. - * 80211.o module will anyway filter frames based on authorization - * state, so this function pointer can be NULL if low-level driver does - * not require event notification about port state changes. - * Currently unused. */ int (*set_port_auth)(struct ieee80211_hw *hw, u8 *addr, int authorized); - - /* Ask the hardware to service the scan request, no need to start - * the scan state machine in stack. */ int (*hw_scan)(struct ieee80211_hw *hw, u8 *ssid, size_t len); - - /* return low-level statistics */ int (*get_stats)(struct ieee80211_hw *hw, struct ieee80211_low_level_stats *stats); - - /* For devices that generate their own beacons and probe response - * or association responses this updates the state of privacy_invoked - * returns 0 for success or an error number */ int (*set_privacy_invoked)(struct ieee80211_hw *hw, int privacy_invoked); - - /* For devices that have internal sequence counters, allow 802.11 - * code to access the current value of a counter */ int (*get_sequence_counter)(struct ieee80211_hw *hw, u8* addr, u8 keyidx, u8 txrx, u32* iv32, u16* iv16); - - /* Configuration of RTS threshold (if device needs it) */ int (*set_rts_threshold)(struct ieee80211_hw *hw, u32 value); - - /* Configuration of fragmentation threshold. - * Assign this if the device does fragmentation by itself, - * if this method is assigned then the stack will not do - * fragmentation. */ int (*set_frag_threshold)(struct ieee80211_hw *hw, u32 value); - - /* Configuration of retry limits (if device needs it) */ int (*set_retry_limit)(struct ieee80211_hw *hw, u32 short_retry, u32 long_retr); - - /* Number of STAs in STA table notification (NULL = disabled). - * Must be atomic. */ void (*sta_table_notification)(struct ieee80211_hw *hw, int num_sta); - - /* Handle ERP IE change notifications. Must be atomic. */ void (*erp_ie_changed)(struct ieee80211_hw *hw, u8 changes, int cts_protection, int preamble); - - /* Flags for the erp_ie_changed changes parameter */ -#define IEEE80211_ERP_CHANGE_PROTECTION (1<<0) /* protection flag changed */ -#define IEEE80211_ERP_CHANGE_PREAMBLE (1<<1) /* barker preamble mode changed */ - - /* Configure TX queue parameters (EDCF (aifs, cw_min, cw_max), - * bursting) for a hardware TX queue. - * queue = IEEE80211_TX_QUEUE_*. - * Must be atomic. */ int (*conf_tx)(struct ieee80211_hw *hw, int queue, const struct ieee80211_tx_queue_params *params); - - /* Get statistics of the current TX queue status. This is used to get - * number of currently queued packets (queue length), maximum queue - * size (limit), and total number of packets sent using each TX queue - * (count). - * Currently unused. */ int (*get_tx_stats)(struct ieee80211_hw *hw, struct ieee80211_tx_queue_stats *stats); - - /* Get the current TSF timer value from firmware/hardware. Currently, - * this is only used for IBSS mode debugging and, as such, is not a - * required function. - * Must be atomic. */ u64 (*get_tsf)(struct ieee80211_hw *hw); - - /* Reset the TSF timer and allow firmware/hardware to synchronize with - * other STAs in the IBSS. This is only used in IBSS mode. This - * function is optional if the firmware/hardware takes full care of - * TSF synchronization. */ void (*reset_tsf)(struct ieee80211_hw *hw); - - /* Setup beacon data for IBSS beacons. Unlike access point (Master), - * IBSS uses a fixed beacon frame which is configured using this - * function. This handler is required only for IBSS mode. */ int (*beacon_update)(struct ieee80211_hw *hw, struct sk_buff *skb, struct ieee80211_tx_control *control); - - /* Determine whether the last IBSS beacon was sent by us. This is - * needed only for IBSS mode and the result of this function is used to - * determine whether to reply to Probe Requests. */ int (*tx_last_beacon)(struct ieee80211_hw *hw); }; -/* Allocate a new hardware device. This must be called once for each - * hardware device. The returned pointer must be used to refer to this - * device when calling other functions. 802.11 code allocates a private data - * area for the low-level driver. The size of this area is given as - * priv_data_len. +/** + * ieee80211_alloc_hw - Allocate a new hardware device + * + * This must be called once for each hardware device. The returned pointer + * must be used to refer to this device when calling other functions. + * mac80211 allocates a private data area for the driver pointed to by + * @priv in &struct ieee80211_hw, the size of this area is given as + * @priv_data_len. + * + * @priv_data_len: length of private data + * @ops: callbacks for this device */ struct ieee80211_hw *ieee80211_alloc_hw(size_t priv_data_len, const struct ieee80211_ops *ops); -/* Register hardware device to the IEEE 802.11 code and kernel. Low-level - * drivers must call this function before using any other IEEE 802.11 - * function except ieee80211_register_hwmode. */ +/** + * ieee80211_register_hw - Register hardware device + * + * You must call this function before any other functions + * except ieee80211_register_hwmode. + * + * @hw: the device to register as returned by ieee80211_alloc_hw() + */ int ieee80211_register_hw(struct ieee80211_hw *hw); -/* driver can use this and ieee80211_get_rx_led_name to get the - * name of the registered LEDs after ieee80211_register_hw - * was called. - * This is useful to set the default trigger on the LED class - * device that your driver should export for each LED the device - * has, that way the default behaviour will be as expected but - * the user can still change it/turn off the LED etc. - */ #ifdef CONFIG_MAC80211_LEDS extern char *__ieee80211_get_tx_led_name(struct ieee80211_hw *hw); extern char *__ieee80211_get_rx_led_name(struct ieee80211_hw *hw); #endif +/** + * ieee80211_get_tx_led_name - get name of TX LED + * + * mac80211 creates a transmit LED trigger for each wireless hardware + * that can be used to drive LEDs if your driver registers a LED device. + * This function returns the name (or %NULL if not configured for LEDs) + * of the trigger so you can automatically link the LED device. + * + * @hw: the hardware to get the LED trigger name for + */ static inline char *ieee80211_get_tx_led_name(struct ieee80211_hw *hw) { #ifdef CONFIG_MAC80211_LEDS @@ -999,6 +1096,16 @@ static inline char *ieee80211_get_tx_led_name(struct ieee80211_hw *hw) #endif } +/** + * ieee80211_get_rx_led_name - get name of RX LED + * + * mac80211 creates a receive LED trigger for each wireless hardware + * that can be used to drive LEDs if your driver registers a LED device. + * This function returns the name (or %NULL if not configured for LEDs) + * of the trigger so you can automatically link the LED device. + * + * @hw: the hardware to get the LED trigger name for + */ static inline char *ieee80211_get_rx_led_name(struct ieee80211_hw *hw) { #ifdef CONFIG_MAC80211_LEDS @@ -1012,29 +1119,80 @@ static inline char *ieee80211_get_rx_led_name(struct ieee80211_hw *hw) int ieee80211_register_hwmode(struct ieee80211_hw *hw, struct ieee80211_hw_mode *mode); -/* Unregister a hardware device. This function instructs 802.11 code to free - * allocated resources and unregister netdevices from the kernel. */ +/** + * ieee80211_unregister_hw - Unregister a hardware device + * + * This function instructs mac80211 to free allocated resources + * and unregister netdevices from the networking subsystem. + * + * @hw: the hardware to unregister + */ void ieee80211_unregister_hw(struct ieee80211_hw *hw); -/* Free everything that was allocated including private data of a driver. */ +/** + * ieee80211_free_hw - free hardware descriptor + * + * This function frees everything that was allocated, including the + * private data for the driver. You must call ieee80211_unregister_hw() + * before calling this function + * + * @hw: the hardware to free + */ void ieee80211_free_hw(struct ieee80211_hw *hw); -/* Receive frame callback function. The low-level driver uses this function to - * send received frames to the IEEE 802.11 code. Receive buffer (skb) must - * start with IEEE 802.11 header. */ +/* trick to avoid symbol clashes with the ieee80211 subsystem */ void __ieee80211_rx(struct ieee80211_hw *hw, struct sk_buff *skb, struct ieee80211_rx_status *status); + +/** + * ieee80211_rx - receive frame + * + * Use this function to hand received frames to mac80211. The receive + * buffer in @skb must start with an IEEE 802.11 header or a radiotap + * header if %RX_FLAG_RADIOTAP is set in the @status flags. + * + * This function may not be called in IRQ context. + * + * @hw: the hardware this frame came in on + * @skb: the buffer to receive, owned by mac80211 after this call + * @status: status of this frame; the status pointer need not be valid + * after this function returns + */ +static inline void ieee80211_rx(struct ieee80211_hw *hw, struct sk_buff *skb, + struct ieee80211_rx_status *status) +{ + __ieee80211_rx(hw, skb, status); +} + +/** + * ieee80211_rx_irqsafe - receive frame + * + * Like ieee80211_rx() but can be called in IRQ context + * (internally defers to a workqueue.) + * + * @hw: the hardware this frame came in on + * @skb: the buffer to receive, owned by mac80211 after this call + * @status: status of this frame; the status pointer need not be valid + * after this function returns and is not freed by mac80211, + * it is recommended that it points to a stack area + */ void ieee80211_rx_irqsafe(struct ieee80211_hw *hw, struct sk_buff *skb, struct ieee80211_rx_status *status); -/* Transmit status callback function. The low-level driver must call this - * function to report transmit status for all the TX frames that had - * req_tx_status set in the transmit control fields. In addition, this should - * be called at least for all unicast frames to provide information for TX rate - * control algorithm. In order to maintain all statistics, this function is - * recommended to be called after each frame, including multicast/broadcast, is - * sent. */ +/** + * ieee80211_tx_status - transmit status callback + * + * Call this function for all transmitted frames after they have been + * transmitted. It is permissible to not call this function for + * multicast frames but this can affect statistics. + * + * @hw: the hardware the frame was transmitted by + * @skb: the frame that was transmitted, owned by mac80211 after this call + * @status: status information for this frame; the status pointer need not + * be valid after this function returns and is not freed by mac80211, + * it is recommended that it points to a stack area + */ void ieee80211_tx_status(struct ieee80211_hw *hw, struct sk_buff *skb, struct ieee80211_tx_status *status); @@ -1166,14 +1324,26 @@ struct sk_buff * ieee80211_get_buffered_bc(struct ieee80211_hw *hw, int if_id, struct ieee80211_tx_control *control); -/* Given an sk_buff with a raw 802.11 header at the data pointer this function +/** + * ieee80211_get_hdrlen_from_skb - get header length from data + * + * Given an skb with a raw 802.11 header at the data pointer this function * returns the 802.11 header length in bytes (not including encryption * headers). If the data in the sk_buff is too short to contain a valid 802.11 * header the function returns 0. + * + * @skb: the frame */ int ieee80211_get_hdrlen_from_skb(const struct sk_buff *skb); -/* Like ieee80211_get_hdrlen_from_skb() but takes a FC in CPU order. */ +/** + * ieee80211_get_hdrlen - get header length from frame control + * + * This function returns the 802.11 header length in bytes (not including + * encryption headers.) + * + * @fc: the frame control field (in CPU endianness) + */ int ieee80211_get_hdrlen(u16 fc); /** @@ -1218,10 +1388,28 @@ void ieee80211_stop_queues(struct ieee80211_hw *hw); */ void ieee80211_wake_queues(struct ieee80211_hw *hw); -/* called by driver to notify scan status completed */ +/** + * ieee80211_scan_completed - completed hardware scan + * + * When hardware scan offload is used (i.e. the hw_scan() callback is + * assigned) this function needs to be called by the driver to notify + * mac80211 that the scan finished. + * + * @hw: the hardware that finished the scan + */ void ieee80211_scan_completed(struct ieee80211_hw *hw); -/* return a pointer to the source address (SA) */ +/** + * ieee80211_get_SA - get pointer to SA + * + * Given an 802.11 frame, this function returns the offset + * to the source address (SA). It does not verify that the + * header is long enough to contain the address, and the + * header must be long enough to contain the frame control + * field. + * + * @hdr: the frame + */ static inline u8 *ieee80211_get_SA(struct ieee80211_hdr *hdr) { u8 *raw = (u8 *) hdr; @@ -1236,7 +1424,17 @@ static inline u8 *ieee80211_get_SA(struct ieee80211_hdr *hdr) return hdr->addr2; } -/* return a pointer to the destination address (DA) */ +/** + * ieee80211_get_DA - get pointer to DA + * + * Given an 802.11 frame, this function returns the offset + * to the destination address (DA). It does not verify that + * the header is long enough to contain the address, and the + * header must be long enough to contain the frame control + * field. + * + * @hdr: the frame + */ static inline u8 *ieee80211_get_DA(struct ieee80211_hdr *hdr) { u8 *raw = (u8 *) hdr; @@ -1247,6 +1445,14 @@ static inline u8 *ieee80211_get_DA(struct ieee80211_hdr *hdr) return hdr->addr1; } +/** + * ieee80211_get_morefrag - determine whether the MOREFRAGS bit is set + * + * This function determines whether the "more fragments" bit is set + * in the frame. + * + * @hdr: the frame + */ static inline int ieee80211_get_morefrag(struct ieee80211_hdr *hdr) { return (le16_to_cpu(hdr->frame_control) & -- 2.30.2