[PATCH v2 09/12] qtnfmac: implement scan timeout

[Sergey Matyukevich]

Userspace tools may hang on scan in the case when scan completion event
is not returned by firmware. This patch implements the scan timeout
to avoid such situation.

Signed-off-by: Igor Mitsyanko <igor.mitsyanko...@quantenna.com>
Signed-off-by: Sergey Matyukevich <sergey.matyukevich...@quantenna.com>
Signed-off-by: Avinash Patil <avina...@quantenna.com>
---
 drivers/net/wireless/quantenna/qtnfmac/cfg80211.c | 22 ++++++++++++++++++----
 drivers/net/wireless/quantenna/qtnfmac/cfg80211.h |  4 ++++
 drivers/net/wireless/quantenna/qtnfmac/core.c     |  2 ++
 drivers/net/wireless/quantenna/qtnfmac/core.h     |  3 +++
 drivers/net/wireless/quantenna/qtnfmac/event.c    |  2 ++
 5 files changed, 29 insertions(+), 4 deletions(-)

diff --git a/drivers/net/wireless/quantenna/qtnfmac/cfg80211.c 
b/drivers/net/wireless/quantenna/qtnfmac/cfg80211.c
index ac8fdc1db482..856fa6e8327e 100644
--- a/drivers/net/wireless/quantenna/qtnfmac/cfg80211.c
+++ b/drivers/net/wireless/quantenna/qtnfmac/cfg80211.c
@@ -579,19 +579,33 @@ qtnf_del_station(struct wiphy *wiphy, struct net_device 
*dev,
        return ret;
 }
 
+static void qtnf_scan_timeout(unsigned long data)
+{
+       struct qtnf_wmac *mac = (struct qtnf_wmac *)data;
+
+       pr_warn("mac%d scan timed out\n", mac->macid);
+       qtnf_scan_done(mac, true);
+}
+
 static int
 qtnf_scan(struct wiphy *wiphy, struct cfg80211_scan_request *request)
 {
        struct qtnf_wmac *mac = wiphy_priv(wiphy);
-       int ret;
 
        mac->scan_req = request;
 
-       ret = qtnf_cmd_send_scan(mac);
-       if (ret)
+       if (qtnf_cmd_send_scan(mac)) {
                pr_err("MAC%u: failed to start scan\n", mac->macid);
+               mac->scan_req = NULL;
+               return -EFAULT;
+       }
 
-       return ret;
+       mac->scan_timeout.data = (unsigned long)mac;
+       mac->scan_timeout.function = qtnf_scan_timeout;
+       mod_timer(&mac->scan_timeout,
+                 jiffies + QTNF_SCAN_TIMEOUT_SEC * HZ);
+
+       return 0;
 }
 
 static int
diff --git a/drivers/net/wireless/quantenna/qtnfmac/cfg80211.h 
b/drivers/net/wireless/quantenna/qtnfmac/cfg80211.h
index 5bd33124a7c8..6a4af52522b8 100644
--- a/drivers/net/wireless/quantenna/qtnfmac/cfg80211.h
+++ b/drivers/net/wireless/quantenna/qtnfmac/cfg80211.h
@@ -34,10 +34,14 @@ static inline void qtnf_scan_done(struct qtnf_wmac *mac, 
bool aborted)
                .aborted = aborted,
        };
 
+       mutex_lock(&mac->mac_lock);
+
        if (mac->scan_req) {
                cfg80211_scan_done(mac->scan_req, &info);
                mac->scan_req = NULL;
        }
+
+       mutex_unlock(&mac->mac_lock);
 }
 
 #endif /* _QTN_FMAC_CFG80211_H_ */
diff --git a/drivers/net/wireless/quantenna/qtnfmac/core.c 
b/drivers/net/wireless/quantenna/qtnfmac/core.c
index 17d17e332a8b..5e60180482d1 100644
--- a/drivers/net/wireless/quantenna/qtnfmac/core.c
+++ b/drivers/net/wireless/quantenna/qtnfmac/core.c
@@ -288,6 +288,8 @@ static struct qtnf_wmac *qtnf_core_mac_alloc(struct 
qtnf_bus *bus,
                mac->iflist[i].mac = mac;
                mac->iflist[i].vifid = i;
                qtnf_sta_list_init(&mac->iflist[i].sta_list);
+               mutex_init(&mac->mac_lock);
+               init_timer(&mac->scan_timeout);
        }
 
        qtnf_mac_init_primary_intf(mac);
diff --git a/drivers/net/wireless/quantenna/qtnfmac/core.h 
b/drivers/net/wireless/quantenna/qtnfmac/core.h
index 099aad76afeb..066fcd1095a0 100644
--- a/drivers/net/wireless/quantenna/qtnfmac/core.h
+++ b/drivers/net/wireless/quantenna/qtnfmac/core.h
@@ -46,6 +46,7 @@
 #define QTNF_MAX_EVENT_QUEUE_LEN       255
 #define QTNF_DEFAULT_BG_SCAN_PERIOD    300
 #define QTNF_MAX_BG_SCAN_PERIOD                0xffff
+#define QTNF_SCAN_TIMEOUT_SEC          15
 
 #define QTNF_DEF_BSS_PRIORITY          0
 #define QTNF_DEF_WDOG_TIMEOUT          5
@@ -147,6 +148,8 @@ struct qtnf_wmac {
        struct cfg80211_scan_request *scan_req;
        struct cfg80211_chan_def chandef;
        struct cfg80211_chan_def csa_chandef;
+       struct mutex mac_lock;  /* lock during wmac speicific ops */
+       struct timer_list scan_timeout;
 };
 
 struct qtnf_hw_info {
diff --git a/drivers/net/wireless/quantenna/qtnfmac/event.c 
b/drivers/net/wireless/quantenna/qtnfmac/event.c
index 43d2e7fd6e02..0fc2814eafad 100644
--- a/drivers/net/wireless/quantenna/qtnfmac/event.c
+++ b/drivers/net/wireless/quantenna/qtnfmac/event.c
@@ -345,6 +345,8 @@ qtnf_event_handle_scan_complete(struct qtnf_wmac *mac,
                return -EINVAL;
        }
 
+       if (timer_pending(&mac->scan_timeout))
+               del_timer_sync(&mac->scan_timeout);
        qtnf_scan_done(mac, le32_to_cpu(status->flags) & QLINK_SCAN_ABORTED);
 
        return 0;
-- 
2.11.0