cfg80211: refactor cfg80211_can_use_iftype_chan()

Separate the code that counts the interface types and channels from
the code that check the interface combinations.  The new function that
checks for combinations is exported so it can be called by the
drivers.

This is done in preparation for moving the interface combinations
checks out of cfg80211.

Signed-off-by: Luciano Coelho <luciano.coelho@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

1 files changed, 22 insertions, 0 deletions

diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h
index 5640dc028bfa..4653e9f75d0d 100644
--- a/include/net/cfg80211.h
+++ b/include/net/cfg80211.h
@@ -4692,6 +4692,28 @@ void cfg80211_crit_proto_stopped(struct wireless_dev *wdev, gfp_t gfp);
  */
 unsigned int ieee80211_get_num_supported_channels(struct wiphy *wiphy);
 
+/**
+ * cfg80211_check_combinations - check interface 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.
+ *
+ * This function can be called by the driver to check whether a
+ * combination of interfaces and their types are allowed according to
+ * the interface combinations.
+ */
+int cfg80211_check_combinations(struct wiphy *wiphy,
+                                const int num_different_channels,
+                                const u8 radar_detect,
+                                const int iftype_num[NUM_NL80211_IFTYPES]);
+
 /* Logging, debugging and troubleshooting/diagnostic helpers. */
 
 /* wiphy_printk helpers, similar to dev_printk */