4 files changed, 18 insertions, 1 deletions

diff --git a/include/linux/nl80211.h b/include/linux/nl80211.h
index b8fa25d741ba..1cee56b3a79a 100644
--- a/include/linux/nl80211.h
+++ b/include/linux/nl80211.h
@@ -773,6 +773,9 @@ enum nl80211_commands {
  *      cache, a wiphy attribute.
  *
  * @NL80211_ATTR_DURATION: Duration of an operation in milliseconds, u32.
+ * @NL80211_ATTR_MAX_REMAIN_ON_CHANNEL_DURATION: Device attribute that
+ *      specifies the maximum duration that can be requested with the
+ *      remain-on-channel operation, in milliseconds, u32.
  *
  * @NL80211_ATTR_COOKIE: Generic 64-bit cookie to identify objects.
  *
@@ -1035,6 +1038,8 @@ enum nl80211_attrs {
 
         NL80211_ATTR_KEY_DEFAULT_TYPES,
 
+        NL80211_ATTR_MAX_REMAIN_ON_CHANNEL_DURATION,
+
         /* add attributes here, update the policy in nl80211.c */
 
         __NL80211_ATTR_AFTER_LAST,
diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h
index 22be7c625b70..f45e15f12446 100644
--- a/include/net/cfg80211.h
+++ b/include/net/cfg80211.h
@@ -1474,6 +1474,9 @@ struct ieee80211_txrx_stypes {
  *
  * @available_antennas: bitmap of antennas which are available to configure.
  *      antenna configuration commands will be rejected unless this is set.
+ *
+ * @max_remain_on_channel_duration: Maximum time a remain-on-channel operation
+ *      may request, if implemented.
  */
 struct wiphy {
         /* assign these fields before you register the wiphy */
@@ -1511,6 +1514,8 @@ struct wiphy {
         char fw_version[ETHTOOL_BUSINFO_LEN];
         u32 hw_version;
 
+        u16 max_remain_on_channel_duration;
+
         u8 max_num_pmkids;
 
         u32 available_antennas;
diff --git a/net/mac80211/main.c b/net/mac80211/main.c
index f7bdb7c78879..d87eb005690f 100644
--- a/net/mac80211/main.c
+++ b/net/mac80211/main.c
@@ -745,6 +745,8 @@ int ieee80211_register_hw(struct ieee80211_hw *hw)
                 }
         }
 
+        local->hw.wiphy->max_remain_on_channel_duration = 5000;
+
         result = wiphy_register(local->hw.wiphy);
         if (result < 0)
                 goto fail_wiphy_register;
diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index 53f044370cde..594a6ac8b9d2 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -755,6 +755,10 @@ static int nl80211_send_wiphy(struct sk_buff *msg, u32 pid, u32 seq, int flags,
 
         nla_nest_end(msg, nl_cmds);
 
+        if (dev->ops->remain_on_channel)
+                NLA_PUT_U32(msg, NL80211_ATTR_MAX_REMAIN_ON_CHANNEL_DURATION,
+                            dev->wiphy.max_remain_on_channel_duration);
+
         /* for now at least assume all drivers have it */
         if (dev->ops->mgmt_tx)
                 NLA_PUT_FLAG(msg, NL80211_ATTR_OFFCHANNEL_TX_OK);
@@ -4228,7 +4232,8 @@ static int nl80211_remain_on_channel(struct sk_buff *skb,
          * We should be on that channel for at least one jiffie,
          * and more than 5 seconds seems excessive.
          */
-        if (!duration || !msecs_to_jiffies(duration) || duration > 5000)
+        if (!duration || !msecs_to_jiffies(duration) ||
+            duration > rdev->wiphy.max_remain_on_channel_duration)
                 return -EINVAL;
 
         if (!rdev->ops->remain_on_channel)