cfg80211: allow drivers to iterate over matching combinations

The patch splits cfg80211_check_combinations()
into an iterator function and a simple iteration
user.

This makes it possible for drivers to asses how
many channels can use given iftype setup. This in
turn can be used for future
multi-interface/multi-channel channel switching.

Signed-off-by: Michal Kazior <michal.kazior@tieto.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

1 files changed, 27 insertions, 0 deletions

diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h
index 9496fe5ea6b4..3dd2cb465540 100644
--- a/include/net/cfg80211.h
+++ b/include/net/cfg80211.h
@@ -4715,6 +4715,33 @@ int cfg80211_check_combinations(struct wiphy *wiphy,
 				const u8 radar_detect,
 				const int iftype_num[NUM_NL80211_IFTYPES]);
 
+/**
+ * cfg80211_iter_combinations - iterate over matching combinations
+ *
+ * @wiphy: the wiphy
+ * @num_different_channels: the number of different channels we want
+ *	to use for verification
+ * @radar_detect: a bitmap where each bit corresponds to a channel
+ *	width where radar detection is needed, as in the definition of
+ *	&struct ieee80211_iface_combination.@radar_detect_widths
+ * @iftype_num: array with the numbers of interfaces of each interface
+ *	type.  The index is the interface type as specified in &enum
+ *	nl80211_iftype.
+ * @iter: function to call for each matching combination
+ * @data: pointer to pass to iter function
+ *
+ * This function can be called by the driver to check what possible
+ * combinations it fits in at a given moment, e.g. for channel switching
+ * purposes.
+ */
+int cfg80211_iter_combinations(struct wiphy *wiphy,
+			       const int num_different_channels,
+			       const u8 radar_detect,
+			       const int iftype_num[NUM_NL80211_IFTYPES],
+			       void (*iter)(const struct ieee80211_iface_combination *c,
+					    void *data),
+			       void *data);
+
 /* Logging, debugging and troubleshooting/diagnostic helpers. */
 
 /* wiphy_printk helpers, similar to dev_printk */