[PATCH] wcn36xx: Implement cancel_hw_scan

[Bjorn Andersson]

In the even that the wcn36xx interface is brought down while a hw_scan
is active we must abort and wait for the ongoing scan to signal
completion to mac80211.

Reported-by: Mart Raudsepp <l...@gentoo.org>
Fixes: 886039036c20 ("wcn36xx: Implement firmware assisted scan")
Signed-off-by: Bjorn Andersson <bjorn.anders...@linaro.org>
---
 drivers/net/wireless/ath/wcn36xx/main.c    | 25 ++++++++++++++++++++++++-
 drivers/net/wireless/ath/wcn36xx/wcn36xx.h |  1 +
 2 files changed, 25 insertions(+), 1 deletion(-)

diff --git a/drivers/net/wireless/ath/wcn36xx/main.c 
b/drivers/net/wireless/ath/wcn36xx/main.c
index a24edf33be93..bb7110f7fc86 100644
--- a/drivers/net/wireless/ath/wcn36xx/main.c
+++ b/drivers/net/wireless/ath/wcn36xx/main.c
@@ -574,6 +574,7 @@ static void wcn36xx_hw_scan_worker(struct work_struct *work)
        struct cfg80211_scan_request *req = wcn->scan_req;
        u8 channels[WCN36XX_HAL_PNO_MAX_NETW_CHANNELS_EX];
        struct cfg80211_scan_info scan_info = {};
+       bool aborted = false;
        int i;
 
        wcn36xx_dbg(WCN36XX_DBG_MAC, "mac80211 scan %d channels worker\n", 
req->n_channels);
@@ -585,6 +586,13 @@ static void wcn36xx_hw_scan_worker(struct work_struct 
*work)
 
        wcn36xx_smd_init_scan(wcn, HAL_SYS_MODE_SCAN);
        for (i = 0; i < req->n_channels; i++) {
+               mutex_lock(&wcn->scan_lock);
+               aborted = wcn->scan_aborted;
+               mutex_unlock(&wcn->scan_lock);
+
+               if (aborted)
+                       break;
+
                wcn->scan_freq = req->channels[i]->center_freq;
                wcn->scan_band = req->channels[i]->band;
 
@@ -596,7 +604,7 @@ static void wcn36xx_hw_scan_worker(struct work_struct *work)
        }
        wcn36xx_smd_finish_scan(wcn, HAL_SYS_MODE_SCAN);
 
-       scan_info.aborted = false;
+       scan_info.aborted = aborted;
        ieee80211_scan_completed(wcn->hw, &scan_info);
 
        mutex_lock(&wcn->scan_lock);
@@ -615,6 +623,8 @@ static int wcn36xx_hw_scan(struct ieee80211_hw *hw,
                mutex_unlock(&wcn->scan_lock);
                return -EBUSY;
        }
+
+       wcn->scan_aborted = false;
        wcn->scan_req = &hw_req->req;
        mutex_unlock(&wcn->scan_lock);
 
@@ -623,6 +633,18 @@ static int wcn36xx_hw_scan(struct ieee80211_hw *hw,
        return 0;
 }
 
+static void wcn36xx_cancel_hw_scan(struct ieee80211_hw *hw,
+                                  struct ieee80211_vif *vif)
+{
+       struct wcn36xx *wcn = hw->priv;
+
+       mutex_lock(&wcn->scan_lock);
+       wcn->scan_aborted = true;
+       mutex_unlock(&wcn->scan_lock);
+
+       cancel_work_sync(&wcn->scan_work);
+}
+
 static void wcn36xx_update_allowed_rates(struct ieee80211_sta *sta,
                                         enum nl80211_band band)
 {
@@ -1034,6 +1056,7 @@ static const struct ieee80211_ops wcn36xx_ops = {
        .tx                     = wcn36xx_tx,
        .set_key                = wcn36xx_set_key,
        .hw_scan                = wcn36xx_hw_scan,
+       .cancel_hw_scan         = wcn36xx_cancel_hw_scan,
        .bss_info_changed       = wcn36xx_bss_info_changed,
        .set_rts_threshold      = wcn36xx_set_rts_threshold,
        .sta_add                = wcn36xx_sta_add,
diff --git a/drivers/net/wireless/ath/wcn36xx/wcn36xx.h 
b/drivers/net/wireless/ath/wcn36xx/wcn36xx.h
index 571e9f76da7e..b52b4da9a967 100644
--- a/drivers/net/wireless/ath/wcn36xx/wcn36xx.h
+++ b/drivers/net/wireless/ath/wcn36xx/wcn36xx.h
@@ -220,6 +220,7 @@ struct wcn36xx {
        int                     scan_freq;
        int                     scan_band;
        struct mutex            scan_lock;
+       bool                    scan_aborted;
 
        /* DXE channels */
        struct wcn36xx_dxe_ch   dxe_tx_l_ch;    /* TX low */
-- 
2.11.0