[PATCH] wpa_supplicant: Set NAN CDW overwrite info

[Andrei Otcheretianski]

Unlike other places in the spec, CDW info field defined in Table 80
doesn't allow using 0 as "applies for all". Set map_id values based on
the number of supported NAN radios.
While at it remove a stale comment that is not valid anymore.

Signed-off-by: Andrei Otcheretianski <andrei.otcheretianski at intel.com>
---
 src/nan/nan.c                   | 26 ++++++++++++++++++++
 src/nan/nan.h                   |  1 +
 wpa_supplicant/nan_supplicant.c | 43 +++++++++++++++++++++++++++------
 3 files changed, 63 insertions(+), 7 deletions(-)

diff --git a/src/nan/nan.c b/src/nan/nan.c
index 3aa244183f..a62edd1025 100644
--- a/src/nan/nan.c
+++ b/src/nan/nan.c
@@ -413,6 +413,32 @@ int nan_update_config(struct nan_data *nan,
 }
 
 
+void nan_set_cdw_overwrite(struct nan_data *nan, int map_id_2g, int map_id_5g)
+{
+	u16 cdw_info;
+
+	if (!nan)
+		return;
+
+	cdw_info = nan->cfg->dev_capa.cdw_info;
+
+	if (map_id_2g >= 0) {
+		cdw_info &= ~NAN_CDW_INFO_2G_OVERRIDE_MASK;
+		cdw_info |= ((map_id_2g << NAN_CDW_INFO_2G_OVERRIDE_POS) &
+			     NAN_CDW_INFO_2G_OVERRIDE_MASK);
+	}
+
+	if (map_id_5g >= 0) {
+		cdw_info &= ~NAN_CDW_INFO_5G_OVERRIDE_MASK;
+		cdw_info |= ((map_id_5g << NAN_CDW_INFO_5G_OVERRIDE_POS) &
+			     NAN_CDW_INFO_5G_OVERRIDE_MASK);
+	}
+
+	wpa_printf(MSG_DEBUG, "NAN: Updated cdw_info=0x%04x", cdw_info);
+	nan->cfg->dev_capa.cdw_info = cdw_info;
+}
+
+
 void nan_flush(struct nan_data *nan)
 {
 	wpa_printf(MSG_DEBUG, "NAN: Reset internal state");
diff --git a/src/nan/nan.h b/src/nan/nan.h
index ae3c3032ab..c8a0594ef0 100644
--- a/src/nan/nan.h
+++ b/src/nan/nan.h
@@ -794,6 +794,7 @@ void nan_deinit(struct nan_data *nan);
 int nan_start(struct nan_data *nan, const struct nan_cluster_config *config);
 int nan_update_config(struct nan_data *nan,
 		      const struct nan_cluster_config *config);
+void nan_set_cdw_overwrite(struct nan_data *nan, int map_id_2g, int map_id_5g);
 void nan_stop(struct nan_data *nan);
 void nan_flush(struct nan_data *nan);
 
diff --git a/wpa_supplicant/nan_supplicant.c b/wpa_supplicant/nan_supplicant.c
index ab9713b455..e641cf8d07 100644
--- a/wpa_supplicant/nan_supplicant.c
+++ b/wpa_supplicant/nan_supplicant.c
@@ -1394,16 +1394,29 @@ int wpas_nan_init(struct wpa_supplicant *wpa_s)
 			   nan.security_capab);
 	}
 
-	/*
-	 * TODO: Set the device capabilities based on configuration and driver
-	 * data. For now do not set 'n_antennas', 'channel_switch_time' and
-	 * 'capa', i.e., indicating that the information is not available. This
-	 * information should also be retrieved from the driver.
-	 */
 	nan.dev_capa.cdw_info =
 		((1 << NAN_CDW_INFO_2G_POS) & NAN_CDW_INFO_2G_MASK) |
 		((1 << NAN_CDW_INFO_5G_POS) & NAN_CDW_INFO_5G_MASK);
 
+	/*
+	 * Table 80 defines the 2.4 GHz and 5 GHz CDW Override Map ID fields
+	 * as mandatory without any option to indicate "applies for all" as in
+	 * other places in the specification that use map_ids.
+	 * At this stage we don't have a local schedule yet, so we will be
+	 * referencing non-existent map_id.
+	 * In case of a single radio devices all maps will be using map_id 1,
+	 * so we can already configure it. Otherwise, we have no choice but to
+	 * leave it  unassigned and let this field be updated when the
+	 * schedule is configured.
+	 *
+	 * TODO: Dual radio devices may want to properly query this information
+	 * from the driver/device.
+	 */
+	if (wpa_s->nan_capa.num_radios == 1) {
+		nan.dev_capa.cdw_info |= 0x1 << NAN_CDW_INFO_2G_OVERRIDE_POS;
+		nan.dev_capa.cdw_info |= 0x1 << NAN_CDW_INFO_5G_OVERRIDE_POS;
+	}
+
 	nan.dev_capa.supported_bands = NAN_DEV_CAPA_SBAND_2G;
 	if (wpa_s->nan_capa.drv_flags &
 	    WPA_DRIVER_FLAGS_NAN_SUPPORT_DUAL_BAND)
@@ -2104,6 +2117,7 @@ int wpas_nan_sched_config_map(struct wpa_supplicant *wpa_s, const char *cmd)
 	int shared_freqs_count, unused_freqs_count, ret = -1;
 	struct bitfield *bf_total;
 	unsigned int expected_bitmap_len;
+	bool cdw_overwrite_2g = false, cdw_overwrite_5g = false;
 
 	if (!wpas_nan_ndp_allowed(wpa_s))
 		return -1;
@@ -2181,9 +2195,17 @@ int wpas_nan_sched_config_map(struct wpa_supplicant *wpa_s, const char *cmd)
 		goto out;
 	}
 
-	/* Parse freq:timebitmap pairs */
+	/* Parse freq:timebitmap pairs and optional CDW overwrite flags */
 	pos++;
 	while ((token = str_token(pos, " ", &context))) {
+		if (os_strcmp(token, "cdw_overwrite_low_band") == 0) {
+			cdw_overwrite_2g = true;
+			continue;
+		}
+		if (os_strcmp(token, "cdw_overwrite_high_band") == 0) {
+			cdw_overwrite_5g = true;
+			continue;
+		}
 		int j, i = sched_cfg->num_channels;
 		struct bitfield *bf_chan = NULL;
 		char *colon = os_strchr(token, ':');
@@ -2360,6 +2382,13 @@ int wpas_nan_sched_config_map(struct wpa_supplicant *wpa_s, const char *cmd)
 		os_memset(sched_cfg, 0, sizeof(*sched_cfg));
 		wpas_nan_update_local_schedule(wpa_s);
 	}
+
+	/* Update CDW overwrite map_id for the specified band */
+	if (cdw_overwrite_2g || cdw_overwrite_5g)
+		nan_set_cdw_overwrite(wpa_s->nan,
+				      cdw_overwrite_2g ? map_id : -1,
+				      cdw_overwrite_5g ? map_id : -1);
+
 out:
 	os_free(bf_total);
 	os_free(shared_freqs);
-- 
2.53.0