qcacld-3.0: Pick a valid channel for NDI start

Currently, NAN 5GHz social channel 44(5220) is picked to start
the BSS for NDI if 5GHz band is supported. But the channel
might get disabled due to regulatory constraints or
user/applications might also disable based on the usecase.
NDI fails to start in such cases.
Pick a valid channel to start the BSS and give preference to
NAN social channels.
Also, don't allow NDI start when NAN discovery is not enabled
to avoid issues due to DBS incase if NDI to be started in
a 2.4GHz channel.

Change-Id: I562d0f4f6a425ad7fb4cd043e696d3d573854b3b
CRs-Fixed: 3068545

core/hdd/src/wlan_hdd_nan_datapath.c

@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 2016-2021 The Linux Foundation. All rights reserved.
+ * Copyright (c) 2021 Qualcomm Innovation Center, Inc. All rights reserved.
  *
  * Permission to use, copy, modify, and/or distribute this software for
  * any purpose with or without fee is hereby granted, provided that the
@@ -200,15 +201,134 @@ static bool hdd_is_ndp_allowed(struct hdd_context *hdd_ctx)
 }
 #endif /* NDP_SAP_CONCURRENCY_ENABLE */
 
+static void hdd_swap_frequencies(uint32_t *a, uint32_t *b)
+{
+	*b ^= *a;
+	*a ^= *b;
+	*b ^= *a;
+}
+
+/**
+ * hdd_ndi_config_ch_list() - Configure the channel list for NDI start
+ * @hdd_ctx: hdd context
+ * @ch_info: Buffer to fill supported channels, give preference to 5220 and 2437
+ * to keep the legacy behavior intact
+ *
+ * Unlike traditional device modes, where the higher application
+ * layer initiates connect / join / start, the NAN data
+ * interface does not have any such formal requests. The NDI
+ * create request is responsible for starting the BSS as well.
+ * Use the 5GHz Band NAN Social channel for BSS start if target
+ * supports it, since a 2.4GHz channel will require a DBS HW mode change
+ * first on a DBS 2x2 MAC target. Use a 2.4 GHz Band NAN Social channel
+ * if the target is not 5GHz capable. If both of these channels are
+ * not available, pick the next available channel. This would be used just to
+ * start the NDI. Actual channel for NDP data transfer would be negotiated with
+ * peer later.
+ *
+ * Return: SUCCESS if some valid channels are obtained
+ */
+static QDF_STATUS
+hdd_ndi_config_ch_list(struct hdd_context *hdd_ctx,
+		       tCsrChannelInfo *ch_info)
+{
+	struct regulatory_channel *cur_chan_list;
+	int i = 0, swap_index = 0;
+	QDF_STATUS status;
+
+	ch_info->numOfChannels = 0;
+	cur_chan_list = qdf_mem_malloc(sizeof(*cur_chan_list) *
+							(NUM_CHANNELS + 2));
+	if (!cur_chan_list)
+		return QDF_STATUS_E_NOMEM;
+
+	status = ucfg_reg_get_current_chan_list(hdd_ctx->pdev, cur_chan_list);
+	if (status != QDF_STATUS_SUCCESS) {
+		hdd_err_rl("Failed to get the current channel list");
+		qdf_mem_free(cur_chan_list);
+		return QDF_STATUS_E_IO;
+	}
+
+	ch_info->freq_list = qdf_mem_malloc(sizeof(uint32_t) * NUM_CHANNELS);
+	if (!ch_info->freq_list) {
+		qdf_mem_free(cur_chan_list);
+		return QDF_STATUS_E_NOMEM;
+	}
+
+	for (i = 0; i < NUM_CHANNELS; i++) {
+		/**
+		 * current channel list includes all channels. Exclude
+		 * disabled channels
+		 */
+		if (cur_chan_list[i].chan_flags & REGULATORY_CHAN_DISABLED ||
+		    cur_chan_list[i].chan_flags & REGULATORY_CHAN_RADAR)
+			continue;
+
+		/**
+		 * do not include 6 GHz channels for now as NAN would need
+		 * 2.4 GHz and 5 GHz channels for discovery.
+		 * <TODO> Need to consider the 6GHz channels when there is a
+		 * case where all 2GHz and 5GHz channels are disabled and
+		 * only 6GHz channels are enabled
+		 */
+		if (wlan_reg_is_6ghz_chan_freq(cur_chan_list[i].center_freq))
+			continue;
+
+		ch_info->freq_list[ch_info->numOfChannels++] =
+					cur_chan_list[i].center_freq;
+	}
+
+	if (!ch_info->numOfChannels) {
+		status = QDF_STATUS_E_NULL_VALUE;
+		qdf_mem_free(ch_info->freq_list);
+		goto end;
+	}
+
+	/**
+	 * Keep the valid channels in list in below order,
+	 * 149, 44, 6, rest of the channels
+	 */
+	for (i = ch_info->numOfChannels - 1; i >= 0; i--) {
+		if (ch_info->freq_list[i] != NAN_SOCIAL_FREQ_5GHZ_UPPER_BAND)
+			continue;
+		hdd_swap_frequencies(&ch_info->freq_list[i],
+				     &ch_info->freq_list[swap_index]);
+		swap_index++;
+		break;
+	}
+
+	for (i = ch_info->numOfChannels - 1; i >= 0; i--) {
+		if (ch_info->freq_list[i] != NAN_SOCIAL_FREQ_5GHZ_LOWER_BAND)
+			continue;
+
+		hdd_swap_frequencies(&ch_info->freq_list[i],
+				     &ch_info->freq_list[swap_index]);
+		swap_index++;
+		break;
+	}
+
+	for (i = ch_info->numOfChannels - 1; i >= 0; i--) {
+		if (ch_info->freq_list[i] != NAN_SOCIAL_FREQ_2_4GHZ)
+			continue;
+
+		hdd_swap_frequencies(&ch_info->freq_list[i],
+				     &ch_info->freq_list[swap_index]);
+		break;
+	}
+
+end:
+	qdf_mem_free(cur_chan_list);
+
+	return status;
+}
+
 /**
  * hdd_ndi_start_bss() - Start BSS on NAN data interface
  * @adapter: adapter context
- * @oper_freq: freq on which the BSS to be started
  *
  * Return: 0 on success, error value on failure
  */
-static int hdd_ndi_start_bss(struct hdd_adapter *adapter,
-			     qdf_freq_t oper_freq)
+static int hdd_ndi_start_bss(struct hdd_adapter *adapter)
 {
 	QDF_STATUS status;
 	uint32_t roam_id;
@@ -244,12 +364,11 @@ static int hdd_ndi_start_bss(struct hdd_adapter *adapter,
 
 	roam_profile->csrPersona = adapter->device_mode;
 
-	if (!oper_freq)
-		oper_freq = NAN_SOCIAL_FREQ_2_4GHZ;
-
-	roam_profile->ChannelInfo.numOfChannels = 1;
-	roam_profile->ChannelInfo.freq_list = (uint32_t *)&oper_freq;
-
+	status = hdd_ndi_config_ch_list(hdd_ctx, &roam_profile->ChannelInfo);
+	if (!QDF_IS_STATUS_SUCCESS(status)) {
+		hdd_err("Get uapsd_mask failed");
+		return -EINVAL;
+	}
 	roam_profile->SSIDs.numOfSSIDs = 1;
 	roam_profile->SSIDs.SSIDList->SSID.length = 0;
 
@@ -273,6 +392,7 @@ static int hdd_ndi_start_bss(struct hdd_adapter *adapter,
 		hdd_info("sme_RoamConnect issued successfully for NDI");
 	}
 
+	qdf_mem_free(roam_profile->ChannelInfo.freq_list);
 	roam_profile->ChannelInfo.freq_list = NULL;
 	roam_profile->ChannelInfo.numOfChannels = 0;
 
@@ -620,7 +740,6 @@ int hdd_ndi_start(char *iface_name, uint16_t transaction_id)
 {
 	int ret;
 	QDF_STATUS status;
-	qdf_freq_t op_freq;
 	struct hdd_adapter *adapter;
 	struct hdd_context *hdd_ctx = cds_get_context(QDF_MODULE_ID_HDD);
 	struct wlan_objmgr_vdev *vdev;
@@ -656,24 +775,8 @@ int hdd_ndi_start(char *iface_name, uint16_t transaction_id)
 	ucfg_nan_set_ndp_create_transaction_id(vdev, transaction_id);
 	ucfg_nan_set_ndi_state(vdev, NAN_DATA_NDI_CREATING_STATE);
 	hdd_objmgr_put_vdev_by_user(vdev, WLAN_OSIF_NAN_ID);
-	/*
-	 * The NAN data interface has been created at this point.
-	 * Unlike traditional device modes, where the higher application
-	 * layer initiates connect / join / start, the NAN data
-	 * interface does not have any such formal requests. The NDI
-	 * create request is responsible for starting the BSS as well.
-	 * Use the 5GHz Band NAN Social channel for BSS start if target
-	 * supports it, since a 2.4GHz channel will require a DBS HW mode change
-	 * first on a DBS 2x2 MAC target. Use a 2.4 GHz Band NAN Social channel
-	 * if the target is not 5GHz capable.
-	 */
-
-	if (hdd_is_5g_supported(hdd_ctx))
-		op_freq = NAN_SOCIAL_FREQ_5GHZ_LOWER_BAND;
-	else
-		op_freq = NAN_SOCIAL_FREQ_2_4GHZ;
 
-	if (hdd_ndi_start_bss(adapter, op_freq)) {
+	if (hdd_ndi_start_bss(adapter)) {
 		hdd_err("NDI start bss failed");
 		ret = -EFAULT;
 		goto err_handler;

os_if/nan/src/os_if_nan.c

@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 2016-2021 The Linux Foundation. All rights reserved.
+ * Copyright (c) 2021 Qualcomm Innovation Center, Inc. All rights reserved.
  *
  * Permission to use, copy, modify, and/or distribute this software for
  * any purpose with or without fee is hereby granted, provided that the
@@ -1055,6 +1056,16 @@ int os_if_nan_process_ndp_cmd(struct wlan_objmgr_psoc *psoc,
 
 	switch (ndp_cmd_type) {
 	case QCA_WLAN_VENDOR_ATTR_NDP_INTERFACE_CREATE:
+		/**
+		 * NDI creation is not allowed if NAN discovery is not running.
+		 * Allowing NDI creation when NAN discovery is not enabled may
+		 * lead to issues if NDI has to be started in a
+		 * 2GHz channel and if the target is not operating in DBS mode.
+		 */
+		if (!ucfg_is_nan_disc_active(psoc)) {
+			osif_err("NDI creation is not allowed when NAN discovery is not running");
+			return -EOPNOTSUPP;
+		}
 		return os_if_nan_process_ndi_create(psoc, tb);
 	case QCA_WLAN_VENDOR_ATTR_NDP_INTERFACE_DELETE:
 		return os_if_nan_process_ndi_delete(psoc, tb);