Retry initial 20/40 MHz co-ex scan if the driver is busy

This makes the initial OBSS scans in AP mode before starting 40 MHz BSS
more robust. In addition, HT20 can be used as a backup option if none of
the scans succeed.

Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com>
This commit is contained in:
Peng Xu 2014-04-16 18:45:53 +03:00 committed by Jouni Malinen
parent 587d60d2b7
commit 5f0bca77a8
4 changed files with 71 additions and 5 deletions

View file

@ -1355,6 +1355,7 @@ void hostapd_interface_deinit(struct hostapd_iface *iface)
#ifdef CONFIG_IEEE80211N #ifdef CONFIG_IEEE80211N
#ifdef NEED_AP_MLME #ifdef NEED_AP_MLME
hostapd_stop_setup_timers(iface);
eloop_cancel_timeout(ap_ht2040_timeout, iface, NULL); eloop_cancel_timeout(ap_ht2040_timeout, iface, NULL);
#endif /* NEED_AP_MLME */ #endif /* NEED_AP_MLME */
#endif /* CONFIG_IEEE80211N */ #endif /* CONFIG_IEEE80211N */

View file

@ -363,6 +363,7 @@ struct hostapd_iface {
#endif /* CONFIG_ACS */ #endif /* CONFIG_ACS */
void (*scan_cb)(struct hostapd_iface *iface); void (*scan_cb)(struct hostapd_iface *iface);
int num_ht40_scan_tries;
}; };
/* hostapd.c */ /* hostapd.c */

View file

@ -602,9 +602,55 @@ static void ieee80211n_scan_channels_5g(struct hostapd_iface *iface,
} }
static void ap_ht40_scan_retry(void *eloop_data, void *user_data)
{
#define HT2040_COEX_SCAN_RETRY 15
struct hostapd_iface *iface = eloop_data;
struct wpa_driver_scan_params params;
int ret;
os_memset(&params, 0, sizeof(params));
if (iface->current_mode->mode == HOSTAPD_MODE_IEEE80211G)
ieee80211n_scan_channels_2g4(iface, &params);
else
ieee80211n_scan_channels_5g(iface, &params);
ret = hostapd_driver_scan(iface->bss[0], &params);
iface->num_ht40_scan_tries++;
os_free(params.freqs);
if (ret == -EBUSY &&
iface->num_ht40_scan_tries < HT2040_COEX_SCAN_RETRY) {
wpa_printf(MSG_ERROR,
"Failed to request a scan of neighboring BSSes ret=%d (%s) - try to scan again (attempt %d)",
ret, strerror(-ret), iface->num_ht40_scan_tries);
eloop_register_timeout(1, 0, ap_ht40_scan_retry, iface, NULL);
return;
}
if (ret == 0) {
iface->scan_cb = ieee80211n_check_scan;
return;
}
wpa_printf(MSG_DEBUG,
"Failed to request a scan in device, bringing up in HT20 mode");
iface->conf->secondary_channel = 0;
iface->conf->ht_capab &= ~HT_CAP_INFO_SUPP_CHANNEL_WIDTH_SET;
hostapd_setup_interface_complete(iface, 0);
}
void hostapd_stop_setup_timers(struct hostapd_iface *iface)
{
eloop_cancel_timeout(ap_ht40_scan_retry, iface, NULL);
}
static int ieee80211n_check_40mhz(struct hostapd_iface *iface) static int ieee80211n_check_40mhz(struct hostapd_iface *iface)
{ {
struct wpa_driver_scan_params params; struct wpa_driver_scan_params params;
int ret;
if (!iface->conf->secondary_channel) if (!iface->conf->secondary_channel)
return 0; /* HT40 not used */ return 0; /* HT40 not used */
@ -617,13 +663,26 @@ static int ieee80211n_check_40mhz(struct hostapd_iface *iface)
ieee80211n_scan_channels_2g4(iface, &params); ieee80211n_scan_channels_2g4(iface, &params);
else else
ieee80211n_scan_channels_5g(iface, &params); ieee80211n_scan_channels_5g(iface, &params);
if (hostapd_driver_scan(iface->bss[0], &params) < 0) {
wpa_printf(MSG_ERROR, "Failed to request a scan of " ret = hostapd_driver_scan(iface->bss[0], &params);
"neighboring BSSes"); os_free(params.freqs);
os_free(params.freqs);
if (ret == -EBUSY) {
wpa_printf(MSG_ERROR,
"Failed to request a scan of neighboring BSSes ret=%d (%s) - try to scan again",
ret, strerror(-ret));
iface->num_ht40_scan_tries = 1;
eloop_cancel_timeout(ap_ht40_scan_retry, iface, NULL);
eloop_register_timeout(1, 0, ap_ht40_scan_retry, iface, NULL);
return 1;
}
if (ret < 0) {
wpa_printf(MSG_ERROR,
"Failed to request a scan of neighboring BSSes ret=%d (%s)",
ret, strerror(-ret));
return -1; return -1;
} }
os_free(params.freqs);
iface->scan_cb = ieee80211n_check_scan; iface->scan_cb = ieee80211n_check_scan;
return 1; return 1;

View file

@ -23,6 +23,7 @@ int hostapd_hw_get_channel(struct hostapd_data *hapd, int freq);
int hostapd_check_ht_capab(struct hostapd_iface *iface); int hostapd_check_ht_capab(struct hostapd_iface *iface);
int hostapd_prepare_rates(struct hostapd_iface *iface, int hostapd_prepare_rates(struct hostapd_iface *iface,
struct hostapd_hw_modes *mode); struct hostapd_hw_modes *mode);
void hostapd_stop_setup_timers(struct hostapd_iface *iface);
#else /* NEED_AP_MLME */ #else /* NEED_AP_MLME */
static inline void static inline void
hostapd_free_hw_features(struct hostapd_hw_modes *hw_features, hostapd_free_hw_features(struct hostapd_hw_modes *hw_features,
@ -61,6 +62,10 @@ static inline int hostapd_prepare_rates(struct hostapd_iface *iface,
return 0; return 0;
} }
static inline void hostapd_stop_setup_timers(struct hostapd_iface *iface)
{
}
#endif /* NEED_AP_MLME */ #endif /* NEED_AP_MLME */
#endif /* HW_FEATURES_H */ #endif /* HW_FEATURES_H */