qcacld-3.0: Update channel_before_switch_band in passive chan switch case

In current scenario, SAP is unable to switch from 2.4GHz to
5Ghz if previous CSA happens with reason CSA_REASON_CHAN_PASSIVE.

For instance, SAP starts on 5Ghz with Country US, and later it
changes to country 00 after MCC. Since in country 00, all 5Ghz
channels are passive, so SAP switches to 2.4Ghz with reason
CSA_REASON_CHAN_PASSIVE. Again if MCC happens to country US then
SAP is unable to switch from 2.4Ghz to 5Ghz. This is because
chan_freq_before_switch_band and chan_width_before_switch_band
are not filled in CSA_REASON_CHAN_PASSIVE case.

As part of fix, in wlansap_get_chan_band_restrict(), update the
chan_freq_before_switch_band and chan_width_before_switch_band
incase channel switch reason is CSA_REASON_CHAN_PASSIVE.

Change-Id: I9610b17cff3f6e0e5257270d2fccd5586c9913f9
CRs-Fixed: 3055017

core/sap/src/sap_module.c

@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 2012-2021 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
@@ -3230,6 +3231,11 @@ qdf_freq_t wlansap_get_chan_band_restrict(struct sap_context *sap_ctx,
 		return wlansap_get_safe_channel_from_pcl_and_acs_range(sap_ctx);
 	} else if (wlan_reg_is_passive_for_freq(mac->pdev,
 						sap_ctx->chan_freq)) {
+		sap_ctx->chan_freq_before_switch_band = sap_ctx->chan_freq;
+		sap_ctx->chan_width_before_switch_band =
+			sap_ctx->ch_params.ch_width;
+		sap_debug("Save chan info before switch: %d, width: %d",
+			  sap_ctx->chan_freq, sap_ctx->ch_params.ch_width);
 		sap_debug("channel is passive");
 		*csa_reason = CSA_REASON_CHAN_PASSIVE;
 		return wlansap_get_safe_channel_from_pcl_for_sap(sap_ctx);