wcn36xx: Implement firmware assisted scan

Using the software based channel scan mechanism from mac80211 keeps us
offline for 10-15 second, we should instead issue a start_scan/end_scan
on each channel reducing this time.

Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>
diff --git a/drivers/net/wireless/ath/wcn36xx/main.c b/drivers/net/wireless/ath/wcn36xx/main.c
index 3c2522b..96a9584 100644
--- a/drivers/net/wireless/ath/wcn36xx/main.c
+++ b/drivers/net/wireless/ath/wcn36xx/main.c
@@ -568,23 +568,59 @@
 	return ret;
 }
 
-static void wcn36xx_sw_scan_start(struct ieee80211_hw *hw,
-				  struct ieee80211_vif *vif,
-				  const u8 *mac_addr)
+static void wcn36xx_hw_scan_worker(struct work_struct *work)
 {
-	struct wcn36xx *wcn = hw->priv;
+	struct wcn36xx *wcn = container_of(work, struct wcn36xx, scan_work);
+	struct cfg80211_scan_request *req = wcn->scan_req;
+	u8 channels[WCN36XX_HAL_PNO_MAX_NETW_CHANNELS_EX];
+	struct cfg80211_scan_info scan_info = {};
+	int i;
+
+	wcn36xx_dbg(WCN36XX_DBG_MAC, "mac80211 scan %d channels worker\n", req->n_channels);
+
+	for (i = 0; i < req->n_channels; i++)
+		channels[i] = req->channels[i]->hw_value;
+
+	wcn36xx_smd_update_scan_params(wcn, channels, req->n_channels);
 
 	wcn36xx_smd_init_scan(wcn, HAL_SYS_MODE_SCAN);
-	wcn36xx_smd_start_scan(wcn);
+	for (i = 0; i < req->n_channels; i++) {
+		wcn->scan_freq = req->channels[i]->center_freq;
+		wcn->scan_band = req->channels[i]->band;
+
+		wcn36xx_smd_start_scan(wcn, req->channels[i]->hw_value);
+		msleep(30);
+		wcn36xx_smd_end_scan(wcn, req->channels[i]->hw_value);
+
+		wcn->scan_freq = 0;
+	}
+	wcn36xx_smd_finish_scan(wcn, HAL_SYS_MODE_SCAN);
+
+	scan_info.aborted = false;
+	ieee80211_scan_completed(wcn->hw, &scan_info);
+
+	mutex_lock(&wcn->scan_lock);
+	wcn->scan_req = NULL;
+	mutex_unlock(&wcn->scan_lock);
 }
 
-static void wcn36xx_sw_scan_complete(struct ieee80211_hw *hw,
-				     struct ieee80211_vif *vif)
+static int wcn36xx_hw_scan(struct ieee80211_hw *hw,
+			   struct ieee80211_vif *vif,
+			   struct ieee80211_scan_request *hw_req)
 {
 	struct wcn36xx *wcn = hw->priv;
 
-	wcn36xx_smd_end_scan(wcn);
-	wcn36xx_smd_finish_scan(wcn, HAL_SYS_MODE_SCAN);
+	mutex_lock(&wcn->scan_lock);
+	if (wcn->scan_req) {
+		mutex_unlock(&wcn->scan_lock);
+		return -EBUSY;
+	}
+	wcn->scan_req = &hw_req->req;
+	mutex_unlock(&wcn->scan_lock);
+
+	schedule_work(&wcn->scan_work);
+
+	return 0;
 }
 
 static void wcn36xx_update_allowed_rates(struct ieee80211_sta *sta,
@@ -997,8 +1033,7 @@
 	.configure_filter       = wcn36xx_configure_filter,
 	.tx			= wcn36xx_tx,
 	.set_key		= wcn36xx_set_key,
-	.sw_scan_start		= wcn36xx_sw_scan_start,
-	.sw_scan_complete	= wcn36xx_sw_scan_complete,
+	.hw_scan		= wcn36xx_hw_scan,
 	.bss_info_changed	= wcn36xx_bss_info_changed,
 	.set_rts_threshold	= wcn36xx_set_rts_threshold,
 	.sta_add		= wcn36xx_sta_add,
@@ -1023,6 +1058,7 @@
 	ieee80211_hw_set(wcn->hw, SUPPORTS_PS);
 	ieee80211_hw_set(wcn->hw, SIGNAL_DBM);
 	ieee80211_hw_set(wcn->hw, HAS_RATE_CONTROL);
+	ieee80211_hw_set(wcn->hw, SINGLE_SCAN_ON_ALL_BANDS);
 
 	wcn->hw->wiphy->interface_modes = BIT(NL80211_IFTYPE_STATION) |
 		BIT(NL80211_IFTYPE_AP) |
@@ -1032,6 +1068,9 @@
 	wcn->hw->wiphy->bands[NL80211_BAND_2GHZ] = &wcn_band_2ghz;
 	wcn->hw->wiphy->bands[NL80211_BAND_5GHZ] = &wcn_band_5ghz;
 
+	wcn->hw->wiphy->max_scan_ssids = WCN36XX_MAX_SCAN_SSIDS;
+	wcn->hw->wiphy->max_scan_ie_len = WCN36XX_MAX_SCAN_IE_LEN;
+
 	wcn->hw->wiphy->cipher_suites = cipher_suites;
 	wcn->hw->wiphy->n_cipher_suites = ARRAY_SIZE(cipher_suites);
 
@@ -1152,6 +1191,9 @@
 	wcn->hw = hw;
 	wcn->dev = &pdev->dev;
 	mutex_init(&wcn->hal_mutex);
+	mutex_init(&wcn->scan_lock);
+
+	INIT_WORK(&wcn->scan_work, wcn36xx_hw_scan_worker);
 
 	wcn->smd_channel = qcom_wcnss_open_channel(wcnss, "WLAN_CTRL", wcn36xx_smd_rsp_process);
 	if (IS_ERR(wcn->smd_channel)) {