diff options
Diffstat (limited to 'include/net/cfg80211.h')
| -rw-r--r-- | include/net/cfg80211.h | 121 |
1 files changed, 115 insertions, 6 deletions
diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h index 6a98b1b3bfde..f2740537b5d6 100644 --- a/include/net/cfg80211.h +++ b/include/net/cfg80211.h @@ -25,6 +25,43 @@ #include <linux/wireless.h> +/** + * DOC: Introduction + * + * cfg80211 is the configuration API for 802.11 devices in Linux. It bridges + * userspace and drivers, and offers some utility functionality associated + * with 802.11. cfg80211 must, directly or indirectly via mac80211, be used + * by all modern wireless drivers in Linux, so that they offer a consistent + * API through nl80211. For backward compatibility, cfg80211 also offers + * wireless extensions to userspace, but hides them from drivers completely. + * + * Additionally, cfg80211 contains code to help enforce regulatory spectrum + * use restrictions. + */ + + +/** + * DOC: Device registration + * + * In order for a driver to use cfg80211, it must register the hardware device + * with cfg80211. This happens through a number of hardware capability structs + * described below. + * + * The fundamental structure for each device is the 'wiphy', of which each + * instance describes a physical wireless device connected to the system. Each + * such wiphy can have zero, one, or many virtual interfaces associated with + * it, which need to be identified as such by pointing the network interface's + * @ieee80211_ptr pointer to a &struct wireless_dev which further describes + * the wireless part of the interface, normally this struct is embedded in the + * network interface's private data area. Drivers can optionally allow creating + * or destroying virtual interfaces on the fly, but without at least one or the + * ability to create some the wireless device isn't useful. + * + * Each wiphy structure contains device capability information, and also has + * a pointer to the various operations the driver offers. The definitions and + * structures here describe these capabilities in detail. + */ + /* * wireless hardware capability structures */ @@ -205,6 +242,21 @@ struct ieee80211_supported_band { */ /** + * DOC: Actions and configuration + * + * Each wireless device and each virtual interface offer a set of configuration + * operations and other actions that are invoked by userspace. Each of these + * actions is described in the operations structure, and the parameters these + * operations use are described separately. + * + * Additionally, some operations are asynchronous and expect to get status + * information via some functions that drivers need to call. + * + * Scanning and BSS list handling with its associated functionality is described + * in a separate chapter. + */ + +/** * struct vif_params - describes virtual interface parameters * @mesh_id: mesh ID to use * @mesh_id_len: length of the mesh ID @@ -570,8 +622,28 @@ struct ieee80211_txq_params { /* from net/wireless.h */ struct wiphy; -/* from net/ieee80211.h */ -struct ieee80211_channel; +/** + * DOC: Scanning and BSS list handling + * + * The scanning process itself is fairly simple, but cfg80211 offers quite + * a bit of helper functionality. To start a scan, the scan operation will + * be invoked with a scan definition. This scan definition contains the + * channels to scan, and the SSIDs to send probe requests for (including the + * wildcard, if desired). A passive scan is indicated by having no SSIDs to + * probe. Additionally, a scan request may contain extra information elements + * that should be added to the probe request. The IEs are guaranteed to be + * well-formed, and will not exceed the maximum length the driver advertised + * in the wiphy structure. + * + * When scanning finds a BSS, cfg80211 needs to be notified of that, because + * it is responsible for maintaining the BSS list; the driver should not + * maintain a list itself. For this notification, various functions exist. + * + * Since drivers do not maintain a BSS list, there are also a number of + * functions to search for a BSS and obtain information about it from the + * BSS structure cfg80211 maintains. The BSS list is also made available + * to userspace. + */ /** * struct cfg80211_ssid - SSID description @@ -1574,8 +1646,10 @@ static inline void *wdev_priv(struct wireless_dev *wdev) return wiphy_priv(wdev->wiphy); } -/* - * Utility functions +/** + * DOC: Utility functions + * + * cfg80211 offers a number of utility functions that can be useful. */ /** @@ -1729,6 +1803,14 @@ unsigned int ieee80211_get_hdrlen_from_skb(const struct sk_buff *skb); unsigned int __attribute_const__ ieee80211_hdrlen(__le16 fc); /** + * DOC: Data path helpers + * + * In addition to generic utilities, cfg80211 also offers + * functions that help implement the data path for devices + * that do not do the 802.11/802.3 conversion on the device. + */ + +/** * ieee80211_data_to_8023 - convert an 802.11 data frame to 802.3 * @skb: the 802.11 data frame * @addr: the device MAC address @@ -1788,8 +1870,10 @@ unsigned int cfg80211_classify8021d(struct sk_buff *skb); */ const u8 *cfg80211_find_ie(u8 eid, const u8 *ies, int len); -/* - * Regulatory helper functions for wiphys +/** + * DOC: Regulatory enforcement infrastructure + * + * TODO */ /** @@ -2192,6 +2276,20 @@ void cfg80211_michael_mic_failure(struct net_device *dev, const u8 *addr, void cfg80211_ibss_joined(struct net_device *dev, const u8 *bssid, gfp_t gfp); /** + * DOC: RFkill integration + * + * RFkill integration in cfg80211 is almost invisible to drivers, + * as cfg80211 automatically registers an rfkill instance for each + * wireless device it knows about. Soft kill is also translated + * into disconnecting and turning all interfaces off, drivers are + * expected to turn off the device when all interfaces are down. + * + * However, devices may have a hard RFkill line, in which case they + * also need to interact with the rfkill subsystem, via cfg80211. + * They can do this with a few helper functions documented here. + */ + +/** * wiphy_rfkill_set_hw_state - notify cfg80211 about hw block state * @wiphy: the wiphy * @blocked: block status @@ -2212,6 +2310,17 @@ void wiphy_rfkill_stop_polling(struct wiphy *wiphy); #ifdef CONFIG_NL80211_TESTMODE /** + * DOC: Test mode + * + * Test mode is a set of utility functions to allow drivers to + * interact with driver-specific tools to aid, for instance, + * factory programming. + * + * This chapter describes how drivers interact with it, for more + * information see the nl80211 book's chapter on it. + */ + +/** * cfg80211_testmode_alloc_reply_skb - allocate testmode reply * @wiphy: the wiphy * @approxlen: an upper bound of the length of the data that will |