ACS: Extract bw40/80/160 freqs out of acs_usable_bwXXX_chan()

This extracts the 3 lists of allowed channels for 40/80/160 MHz
bandwidth out of their respective functions. It also adds for each
segment the frequency of the segment's last channel and the index of the
segment's "center" channel.

This is preparative work to allow selecting a channel which is not the
first of its segment for 40/80/160 MHz. In addition, this adds the 5 GHz
160 MHz channel defined for 5735-5895 MHz (channels 149-177).

Signed-off-by: Nicolas Escande <nico.escande@gmail.com>

diff --git a/src/ap/acs.c b/src/ap/acs.c
index 8ee2e04a2c35c3ffc32649158bd996d7c41caba1..03761aec865389fd0675ff0ec2b5c8e240e062b7 100644 (file)
--- a/src/ap/acs.c
+++ b/src/ap/acs.c
@@ -241,6 +241,57 @@
  * [1] http://en.wikipedia.org/wiki/Near_and_far_field
  */
 
+enum bw_type {
+       ACS_BW40,
+       ACS_BW80,
+       ACS_BW160,
+};
+
+struct bw_item {
+       int first;
+       int last;
+       int center_chan;
+};
+
+static const struct bw_item bw_40[] = {
+       { 5180, 5200, 38 }, { 5220, 5240, 46 }, { 5260, 5280, 54 },
+       { 5300, 5320, 62 }, { 5500, 5520, 102 }, { 5540, 5560, 110 },
+       { 5580, 5600, 110 }, { 5620, 5640, 126}, { 5660, 5680, 134 },
+       { 5700, 5720, 142 }, { 5745, 5765, 151 }, { 5785, 5805, 159 },
+       { 5825, 5845, 167 }, { 5865, 5885, 175 },
+       { 5955, 5975, 3 }, { 5995, 6015, 11 }, { 6035, 6055, 19 },
+       { 6075, 6095, 27 }, { 6115, 6135, 35 }, { 6155, 6175, 43 },
+       { 6195, 6215, 51 }, { 6235, 6255, 59 }, { 6275, 6295, 67 },
+       { 6315, 6335, 75 }, { 6355, 6375, 83 }, { 6395, 6415, 91 },
+       { 6435, 6455, 99 }, { 6475, 6495, 107 }, { 6515, 6535, 115 },
+       { 6555, 6575, 123 }, { 6595, 6615, 131 }, { 6635, 6655, 139 },
+       { 6675, 6695, 147 }, { 6715, 6735, 155 }, { 6755, 6775, 163 },
+       { 6795, 6815, 171 }, { 6835, 6855, 179 }, { 6875, 6895, 187 },
+       { 6915, 6935, 195 }, { 6955, 6975, 203 }, { 6995, 7015, 211 },
+       { 7035, 7055, 219 }, { 7075, 7095, 227}, { -1, -1, -1 }
+};
+static const struct bw_item bw_80[] = {
+       { 5180, 5240, 42 }, { 5260, 5320, 58 }, { 5500, 5560, 106 },
+       { 5580, 5640, 122 }, { 5660, 5720, 138 }, { 5745, 5805, 155 },
+       { 5825, 5885, 171},
+       { 5955, 6015, 7 }, { 6035, 6095, 23 }, { 6115, 6175, 39 },
+       { 6195, 6255, 55 }, { 6275, 6335, 71 }, { 6355, 6415, 87 },
+       { 6435, 6495, 103 }, { 6515, 6575, 119 }, { 6595, 6655, 135 },
+       { 6675, 6735, 151 }, { 6755, 6815, 167 }, { 6835, 6895, 183 },
+       { 6915, 6975, 199 }, { 6995, 7055, 215 }, { -1, -1, -1 }
+};
+static const struct bw_item bw_160[] = {
+       { 5180, 5320, 50 }, { 5500, 5640, 114 }, { 5745, 5885, 163 },
+       { 5955, 6095, 15 }, { 6115, 6255, 47 }, { 6275, 6415, 79 },
+       { 6435, 6575, 111 }, { 6595, 6735, 143 },
+       { 6755, 6895, 175 }, { 6915, 7055, 207 }, { -1, -1, -1 }
+};
+static const struct bw_item *bw_desc[] = {
+       [ACS_BW40] = bw_40,
+       [ACS_BW80] = bw_80,
+       [ACS_BW160] = bw_160,
+};
+
 
 static int acs_request_scan(struct hostapd_iface *iface);
 static int acs_survey_is_sufficient(struct freq_survey *survey);
@@ -370,50 +421,18 @@ acs_survey_chan_interference_factor(struct hostapd_iface *iface,
 }
 
 
-static int acs_usable_bw40_chan(const struct hostapd_channel_data *chan)
+static bool acs_usable_bw_chan(const struct hostapd_channel_data *chan,
+                              enum bw_type bw)
 {
-       const int allowed[] = { 5180, 5220, 5260, 5300, 5500, 5540, 5580, 5620,
-                               5660, 5745, 5785, 4920, 4960, 5955, 5995, 6035,
-                               6075, 6115, 6155, 6195, 6235, 6275, 6315, 6355,
-                               6395, 6435, 6475, 6515, 6555, 6595, 6635, 6675,
-                               6715, 6755, 6795, 6835, 6875, 6915, 6955, 6995,
-                               7035, 7075 };
-       unsigned int i;
-
-       for (i = 0; i < ARRAY_SIZE(allowed); i++)
-               if (chan->freq == allowed[i])
-                       return 1;
-
-       return 0;
-}
-
-
-static int acs_usable_bw80_chan(const struct hostapd_channel_data *chan)
-{
-       const int allowed[] = { 5180, 5260, 5500, 5580, 5660, 5745, 5955, 6035,
-                               6115, 6195, 6275, 6355, 6435, 6515, 6595, 6675,
-                               6755, 6835, 6915, 6995 };
-       unsigned int i;
-
-       for (i = 0; i < ARRAY_SIZE(allowed); i++)
-               if (chan->freq == allowed[i])
-                       return 1;
-
-       return 0;
-}
-
-
-static int acs_usable_bw160_chan(const struct hostapd_channel_data *chan)
-{
-       const int allowed[] = { 5180, 5500, 5955, 6115, 6275, 6435, 6595, 6755,
-                               6915 };
-       unsigned int i;
+       unsigned int i = 0;
 
-       for (i = 0; i < ARRAY_SIZE(allowed); i++)
-               if (chan->freq == allowed[i])
-                       return 1;
+       while (bw_desc[bw][i].first != -1) {
+               if (chan->freq == bw_desc[bw][i].first)
+                       return true;
+               i++;
+       }
 
-       return 0;
+       return false;
 }
 
 
@@ -713,7 +732,7 @@ acs_find_ideal_chan_mode(struct hostapd_iface *iface,
                    ((iface->conf->ieee80211n &&
                      iface->conf->secondary_channel) ||
                     is_6ghz_freq(chan->freq)) &&
-                   !acs_usable_bw40_chan(chan)) {
+                   !acs_usable_bw_chan(chan, ACS_BW40)) {
                        wpa_printf(MSG_DEBUG,
                                   "ACS: Channel %d: not allowed as primary channel for 40 MHz bandwidth",
                                   chan->chan);
@@ -724,7 +743,7 @@ acs_find_ideal_chan_mode(struct hostapd_iface *iface,
                    (iface->conf->ieee80211ac || iface->conf->ieee80211ax)) {
                        if (hostapd_get_oper_chwidth(iface->conf) ==
                            CONF_OPER_CHWIDTH_80MHZ &&
-                           !acs_usable_bw80_chan(chan)) {
+                           !acs_usable_bw_chan(chan, ACS_BW80)) {
                                wpa_printf(MSG_DEBUG,
                                           "ACS: Channel %d: not allowed as primary channel for 80 MHz bandwidth",
                                           chan->chan);
@@ -733,7 +752,7 @@ acs_find_ideal_chan_mode(struct hostapd_iface *iface,
 
                        if (hostapd_get_oper_chwidth(iface->conf) ==
                            CONF_OPER_CHWIDTH_160MHZ &&
-                           !acs_usable_bw160_chan(chan)) {
+                           !acs_usable_bw_chan(chan, ACS_BW160)) {
                                wpa_printf(MSG_DEBUG,
                                           "ACS: Channel %d: not allowed as primary channel for 160 MHz bandwidth",
                                           chan->chan);