Extract BSS coex 40 MHz check into a separate function

Move this implementation from check_40mhz_2g4() into a new helper
function check_bss_coex_40mhz function() so that it can be used in the
station mode case as well as the previously used AP mode case.

Signed-off-by: Sergey Matyukevich <sergey.matyukevich.os@quantenna.com>

diff --git a/src/common/hw_features_common.c b/src/common/hw_features_common.c
index 27a138f9adc8d82009add3f48ccce01e334d9733..19593a521f9e5b89eccd8e6e03cdddc38b314bb9 100644 (file)
--- a/src/common/hw_features_common.c
+++ b/src/common/hw_features_common.c
@@ -279,12 +279,87 @@ static int check_20mhz_bss(struct wpa_scan_res *bss, int pri_freq, int start,
 }
 
 
+/*
+ * Returns:
+ * 0: no impact
+ * 1: overlapping BSS
+ * 2: overlapping BSS with 40 MHz intolerant advertisement
+ */
+int check_bss_coex_40mhz(struct wpa_scan_res *bss, int pri_freq, int sec_freq)
+{
+       int affected_start, affected_end;
+       struct ieee802_11_elems elems;
+       int pri_chan, sec_chan;
+       int pri = bss->freq;
+       int sec = pri;
+
+       if (pri_freq == sec_freq)
+               return 1;
+
+       affected_start = (pri_freq + sec_freq) / 2 - 25;
+       affected_end = (pri_freq + sec_freq) / 2 + 25;
+
+       /* Check for overlapping 20 MHz BSS */
+       if (check_20mhz_bss(bss, pri_freq, affected_start, affected_end)) {
+               wpa_printf(MSG_DEBUG, "Overlapping 20 MHz BSS is found");
+               return 1;
+       }
+
+       get_pri_sec_chan(bss, &pri_chan, &sec_chan);
+
+       if (sec_chan) {
+               if (sec_chan < pri_chan)
+                       sec = pri - 20;
+               else
+                       sec = pri + 20;
+       }
+
+       if ((pri < affected_start || pri > affected_end) &&
+           (sec < affected_start || sec > affected_end))
+               return 0; /* not within affected channel range */
+
+       wpa_printf(MSG_DEBUG, "Neighboring BSS: " MACSTR
+                  " freq=%d pri=%d sec=%d",
+                  MAC2STR(bss->bssid), bss->freq, pri_chan, sec_chan);
+
+       if (sec_chan) {
+               if (pri_freq != pri || sec_freq != sec) {
+                       wpa_printf(MSG_DEBUG,
+                                  "40 MHz pri/sec mismatch with BSS "
+                                  MACSTR
+                                  " <%d,%d> (chan=%d%c) vs. <%d,%d>",
+                                  MAC2STR(bss->bssid),
+                                  pri, sec, pri_chan,
+                                  sec > pri ? '+' : '-',
+                                  pri_freq, sec_freq);
+                       return 1;
+               }
+       }
+
+       ieee802_11_parse_elems((u8 *) (bss + 1), bss->ie_len, &elems, 0);
+       if (elems.ht_capabilities) {
+               struct ieee80211_ht_capabilities *ht_cap =
+                       (struct ieee80211_ht_capabilities *)
+                       elems.ht_capabilities;
+
+               if (le_to_host16(ht_cap->ht_capabilities_info) &
+                   HT_CAP_INFO_40MHZ_INTOLERANT) {
+                       wpa_printf(MSG_DEBUG,
+                                  "40 MHz Intolerant is set on channel %d in BSS "
+                                  MACSTR, pri, MAC2STR(bss->bssid));
+                       return 2;
+               }
+       }
+
+       return 0;
+}
+
+
 int check_40mhz_2g4(struct hostapd_hw_modes *mode,
                    struct wpa_scan_results *scan_res, int pri_chan,
                    int sec_chan)
 {
        int pri_freq, sec_freq;
-       int affected_start, affected_end;
        size_t i;
 
        if (!mode || !scan_res || !pri_chan || !sec_chan ||
@@ -294,70 +369,12 @@ int check_40mhz_2g4(struct hostapd_hw_modes *mode,
        pri_freq = hw_get_freq(mode, pri_chan);
        sec_freq = hw_get_freq(mode, sec_chan);
 
-       affected_start = (pri_freq + sec_freq) / 2 - 25;
-       affected_end = (pri_freq + sec_freq) / 2 + 25;
        wpa_printf(MSG_DEBUG, "40 MHz affected channel range: [%d,%d] MHz",
-                  affected_start, affected_end);
+                  (pri_freq + sec_freq) / 2 - 25,
+                  (pri_freq + sec_freq) / 2 + 25);
        for (i = 0; i < scan_res->num; i++) {
-               struct wpa_scan_res *bss = scan_res->res[i];
-               int pri = bss->freq;
-               int sec = pri;
-               struct ieee802_11_elems elems;
-
-               /* Check for overlapping 20 MHz BSS */
-               if (check_20mhz_bss(bss, pri_freq, affected_start,
-                                   affected_end)) {
-                       wpa_printf(MSG_DEBUG,
-                                  "Overlapping 20 MHz BSS is found");
+               if (check_bss_coex_40mhz(scan_res->res[i], pri_freq, sec_freq))
                        return 0;
-               }
-
-               get_pri_sec_chan(bss, &pri_chan, &sec_chan);
-
-               if (sec_chan) {
-                       if (sec_chan < pri_chan)
-                               sec = pri - 20;
-                       else
-                               sec = pri + 20;
-               }
-
-               if ((pri < affected_start || pri > affected_end) &&
-                   (sec < affected_start || sec > affected_end))
-                       continue; /* not within affected channel range */
-
-               wpa_printf(MSG_DEBUG, "Neighboring BSS: " MACSTR
-                          " freq=%d pri=%d sec=%d",
-                          MAC2STR(bss->bssid), bss->freq, pri_chan, sec_chan);
-
-               if (sec_chan) {
-                       if (pri_freq != pri || sec_freq != sec) {
-                               wpa_printf(MSG_DEBUG,
-                                          "40 MHz pri/sec mismatch with BSS "
-                                          MACSTR
-                                          " <%d,%d> (chan=%d%c) vs. <%d,%d>",
-                                          MAC2STR(bss->bssid),
-                                          pri, sec, pri_chan,
-                                          sec > pri ? '+' : '-',
-                                          pri_freq, sec_freq);
-                               return 0;
-                       }
-               }
-
-               ieee802_11_parse_elems((u8 *) (bss + 1), bss->ie_len, &elems,
-                                      0);
-               if (elems.ht_capabilities) {
-                       struct ieee80211_ht_capabilities *ht_cap =
-                               (struct ieee80211_ht_capabilities *)
-                               elems.ht_capabilities;
-
-                       if (le_to_host16(ht_cap->ht_capabilities_info) &
-                           HT_CAP_INFO_40MHZ_INTOLERANT) {
-                               wpa_printf(MSG_DEBUG,
-                                          "40 MHz Intolerant is set on channel %d in BSS "
-                                          MACSTR, pri, MAC2STR(bss->bssid));
-                               return 0;
-                       }
-               }
        }
 
        return 1;

diff --git a/src/common/hw_features_common.h b/src/common/hw_features_common.h
index 2dba34b3e41101875a024f3e4dc2e211369f6ab0..e57a8d65cc4866f618560e0a038441bb72a539a5 100644 (file)
--- a/src/common/hw_features_common.h
+++ b/src/common/hw_features_common.h
@@ -29,6 +29,7 @@ void get_pri_sec_chan(struct wpa_scan_res *bss, int *pri_chan, int *sec_chan);
 int check_40mhz_5g(struct wpa_scan_results *scan_res,
                   struct hostapd_channel_data *pri_chan,
                   struct hostapd_channel_data *sec_chan);
+int check_bss_coex_40mhz(struct wpa_scan_res *bss, int pri_freq, int sec_freq);
 int check_40mhz_2g4(struct hostapd_hw_modes *mode,
                    struct wpa_scan_results *scan_res, int pri_chan,
                    int sec_chan);