hostapd: Select any supported channel if ACS fails

Signed-hostap: Helmut Schaa <helmut.schaa@googlemail.com>
This commit is contained in:
Helmut Schaa 2013-10-23 00:27:34 +03:00 committed by Jouni Malinen
parent 20f9cb1842
commit 677cf19091

View File

@ -472,7 +472,7 @@ static struct hostapd_channel_data *acs_find_chan(struct hostapd_iface *iface,
for (i = 0; i < iface->current_mode->num_channels; i++) { for (i = 0; i < iface->current_mode->num_channels; i++) {
chan = &iface->current_mode->channels[i]; chan = &iface->current_mode->channels[i];
if (!acs_usable_chan(chan)) if (chan->flag & HOSTAPD_CHAN_DISABLED)
continue; continue;
if (chan->freq == freq) if (chan->freq == freq)
@ -492,7 +492,8 @@ static struct hostapd_channel_data *acs_find_chan(struct hostapd_iface *iface,
static struct hostapd_channel_data * static struct hostapd_channel_data *
acs_find_ideal_chan(struct hostapd_iface *iface) acs_find_ideal_chan(struct hostapd_iface *iface)
{ {
struct hostapd_channel_data *chan, *adj_chan, *ideal_chan = NULL; struct hostapd_channel_data *chan, *adj_chan, *ideal_chan = NULL,
*rand_chan = NULL;
long double factor, ideal_factor = 0; long double factor, ideal_factor = 0;
int i, j; int i, j;
int n_chans = 1; int n_chans = 1;
@ -524,9 +525,10 @@ acs_find_ideal_chan(struct hostapd_iface *iface)
for (i = 0; i < iface->current_mode->num_channels; i++) { for (i = 0; i < iface->current_mode->num_channels; i++) {
chan = &iface->current_mode->channels[i]; chan = &iface->current_mode->channels[i];
if (!acs_usable_chan(chan)) if (chan->flag & HOSTAPD_CHAN_DISABLED)
continue; continue;
/* HT40 on 5 GHz has a limited set of primary channels as per /* HT40 on 5 GHz has a limited set of primary channels as per
* 11n Annex J */ * 11n Annex J */
if (iface->current_mode->mode == HOSTAPD_MODE_IEEE80211A && if (iface->current_mode->mode == HOSTAPD_MODE_IEEE80211A &&
@ -538,14 +540,17 @@ acs_find_ideal_chan(struct hostapd_iface *iface)
continue; continue;
} }
factor = chan->interference_factor; factor = 0;
if (acs_usable_chan(chan))
factor = chan->interference_factor;
for (j = 1; j < n_chans; j++) { for (j = 1; j < n_chans; j++) {
adj_chan = acs_find_chan(iface, chan->freq + (j * 20)); adj_chan = acs_find_chan(iface, chan->freq + (j * 20));
if (!adj_chan) if (!adj_chan)
break; break;
factor += adj_chan->interference_factor; if (acs_usable_chan(adj_chan))
factor += adj_chan->interference_factor;
} }
if (j != n_chans) { if (j != n_chans) {
@ -564,22 +569,22 @@ acs_find_ideal_chan(struct hostapd_iface *iface)
adj_chan = acs_find_chan(iface, chan->freq + adj_chan = acs_find_chan(iface, chan->freq +
(j * 20) - 5); (j * 20) - 5);
if (adj_chan) if (adj_chan && acs_usable_chan(adj_chan))
factor += adj_chan->interference_factor; factor += adj_chan->interference_factor;
adj_chan = acs_find_chan(iface, chan->freq + adj_chan = acs_find_chan(iface, chan->freq +
(j * 20) - 10); (j * 20) - 10);
if (adj_chan) if (adj_chan && acs_usable_chan(adj_chan))
factor += adj_chan->interference_factor; factor += adj_chan->interference_factor;
adj_chan = acs_find_chan(iface, chan->freq + adj_chan = acs_find_chan(iface, chan->freq +
(j * 20) + 5); (j * 20) + 5);
if (adj_chan) if (adj_chan && acs_usable_chan(adj_chan))
factor += adj_chan->interference_factor; factor += adj_chan->interference_factor;
adj_chan = acs_find_chan(iface, chan->freq + adj_chan = acs_find_chan(iface, chan->freq +
(j * 20) + 10); (j * 20) + 10);
if (adj_chan) if (adj_chan && acs_usable_chan(adj_chan))
factor += adj_chan->interference_factor; factor += adj_chan->interference_factor;
} }
} }
@ -587,17 +592,24 @@ acs_find_ideal_chan(struct hostapd_iface *iface)
wpa_printf(MSG_DEBUG, "ACS: * channel %d: total interference = %Lg", wpa_printf(MSG_DEBUG, "ACS: * channel %d: total interference = %Lg",
chan->chan, factor); chan->chan, factor);
if (!ideal_chan || factor < ideal_factor) { if (acs_usable_chan(chan) &&
(!ideal_chan || factor < ideal_factor)) {
ideal_factor = factor; ideal_factor = factor;
ideal_chan = chan; ideal_chan = chan;
} }
/* This channel would at least be usable */
if (!rand_chan)
rand_chan = chan;
} }
if (ideal_chan) if (ideal_chan) {
wpa_printf(MSG_DEBUG, "ACS: Ideal channel is %d (%d MHz) with total interference factor of %Lg", wpa_printf(MSG_DEBUG, "ACS: Ideal channel is %d (%d MHz) with total interference factor of %Lg",
ideal_chan->chan, ideal_chan->freq, ideal_factor); ideal_chan->chan, ideal_chan->freq, ideal_factor);
return ideal_chan;
}
return ideal_chan; return rand_chan;
} }