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* [PATCH 1/2] mac80211: add offload channel switch support
@ 2010-05-06  3:34 wey-yi.w.guy
  2010-05-06  3:34 ` [PATCH 2/2] mac80211: check channel switch mode for future frames transmit wey-yi.w.guy
  2010-05-06  7:44 ` [PATCH 1/2] mac80211: add offload channel switch support Johannes Berg
  0 siblings, 2 replies; 4+ messages in thread
From: wey-yi.w.guy @ 2010-05-06  3:34 UTC (permalink / raw)
  To: johannes; +Cc: linux-wireless, Wey-Yi Guy

From: Wey-Yi Guy <wey-yi.w.guy@intel.com>

Adding support to offload the channel switch operation to driver if
driver can support the function.

The original approach, mac80211 utilize the mac_config callback function
and set the CHANNEL_CHANGE flag which is difficult to separate the true
channel switch request from all the other channel changes condition;
with this offload approach, driver has more control on how to handle the
channel switch request from AP, also can provide more accurate timing
calculation

Signed-off-by: Wey-Yi Guy <wey-yi.w.guy@intel.com>
---
 include/net/mac80211.h      |   32 ++++++++++++++++++++++++++
 net/mac80211/driver-ops.h   |   11 +++++++++
 net/mac80211/driver-trace.h |   49 +++++++++++++++++++++++++++++++++++++++
 net/mac80211/ieee80211_i.h  |    3 +-
 net/mac80211/mlme.c         |   53 +++++++++++++++++++++++++++++++++++++++---
 5 files changed, 143 insertions(+), 5 deletions(-)

diff --git a/include/net/mac80211.h b/include/net/mac80211.h
index 2879c8e..dc5ae23 100644
--- a/include/net/mac80211.h
+++ b/include/net/mac80211.h
@@ -708,6 +708,26 @@ struct ieee80211_conf {
 };
 
 /**
+ * struct ieee80211_channel_switch - holds the channel switch data
+ *
+ * The information provided in this structure is required for channel switch
+ * operation.
+ *
+ * @timestamp: value in microseconds of the 64-bit Time Synchronization
+ *	Function (TSF) timer when the channel switch ie received.
+ * @block_tx: set to true if no more future frames transmission within the BSS
+ *	until the scheduled channel switch
+ * @channel: pointer to ieee80211_channel contain then new channel information
+ * @count: specified the number of TBTT's until the channel switch event.
+ */
+struct ieee80211_channel_switch {
+	u64 timestamp;
+	bool block_tx;
+	struct ieee80211_channel *channel;
+	u8 count;
+};
+
+/**
  * struct ieee80211_vif - per-interface data
  *
  * Data in this structure is continually present for driver
@@ -1694,6 +1714,8 @@ struct ieee80211_ops {
 	int (*testmode_cmd)(struct ieee80211_hw *hw, void *data, int len);
 #endif
 	void (*flush)(struct ieee80211_hw *hw, bool drop);
+	void (*channel_switch)(struct ieee80211_hw *hw,
+			       struct ieee80211_channel_switch *ch_switch);
 };
 
 /**
@@ -2444,6 +2466,16 @@ void ieee80211_cqm_rssi_notify(struct ieee80211_vif *vif,
 			       enum nl80211_cqm_rssi_threshold_event rssi_event,
 			       gfp_t gfp);
 
+/**
+ * ieee80211_chswitch_done - Complete channel switch process
+ * @vif: &struct ieee80211_vif pointer from the add_interface callback.
+ * @is_seccess: make the channel switch successful or not
+ *
+ * Complete the channel switch post-process: set the new operational channel
+ * and wake up the suspended queues.
+ */
+void ieee80211_chswitch_done(struct ieee80211_vif *vif, bool is_success);
+
 /* Rate control API */
 
 /**
diff --git a/net/mac80211/driver-ops.h b/net/mac80211/driver-ops.h
index 997008e..5662bb5 100644
--- a/net/mac80211/driver-ops.h
+++ b/net/mac80211/driver-ops.h
@@ -373,4 +373,15 @@ static inline void drv_flush(struct ieee80211_local *local, bool drop)
 	if (local->ops->flush)
 		local->ops->flush(&local->hw, drop);
 }
+
+static inline void drv_channel_switch(struct ieee80211_local *local,
+				     struct ieee80211_channel_switch *ch_switch)
+{
+	might_sleep();
+
+	local->ops->channel_switch(&local->hw, ch_switch);
+
+	trace_drv_channel_switch(local, ch_switch);
+}
+
 #endif /* __MAC80211_DRIVER_OPS */
diff --git a/net/mac80211/driver-trace.h b/net/mac80211/driver-trace.h
index ce734b5..cd1ae9f 100644
--- a/net/mac80211/driver-trace.h
+++ b/net/mac80211/driver-trace.h
@@ -774,6 +774,34 @@ TRACE_EVENT(drv_flush,
 	)
 );
 
+TRACE_EVENT(drv_channel_switch,
+	TP_PROTO(struct ieee80211_local *local,
+		 struct ieee80211_channel_switch *ch_switch),
+
+	TP_ARGS(local, ch_switch),
+
+	TP_STRUCT__entry(
+		LOCAL_ENTRY
+		__field(u64, timestamp)
+		__field(bool, block_tx)
+		__field(u16, freq)
+		__field(u8, count)
+	),
+
+	TP_fast_assign(
+		LOCAL_ASSIGN;
+		__entry->timestamp = ch_switch->timestamp;
+		__entry->block_tx = ch_switch->block_tx;
+		__entry->freq = ch_switch->channel->center_freq;
+		__entry->count = ch_switch->count;
+	),
+
+	TP_printk(
+		LOCAL_PR_FMT " new freq:%u count:%d",
+		LOCAL_PR_ARG, __entry->freq, __entry->count
+	)
+);
+
 /*
  * Tracing for API calls that drivers call.
  */
@@ -992,6 +1020,27 @@ TRACE_EVENT(api_sta_block_awake,
 	)
 );
 
+TRACE_EVENT(api_chswitch_done,
+	TP_PROTO(struct ieee80211_sub_if_data *sdata, bool is_success),
+
+	TP_ARGS(sdata, is_success),
+
+	TP_STRUCT__entry(
+		VIF_ENTRY
+		__field(bool, is_success)
+	),
+
+	TP_fast_assign(
+		VIF_ASSIGN;
+		__entry->is_success = is_success;
+	),
+
+	TP_printk(
+		VIF_PR_FMT " chswitch:%d",
+		VIF_PR_ARG, __entry->is_success
+	)
+);
+
 /*
  * Tracing for internal functions
  * (which may also be called in response to driver calls)
diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h
index 4e73660..be9dda9 100644
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -999,7 +999,8 @@ int ieee80211_max_network_latency(struct notifier_block *nb,
 				  unsigned long data, void *dummy);
 void ieee80211_sta_process_chanswitch(struct ieee80211_sub_if_data *sdata,
 				      struct ieee80211_channel_sw_ie *sw_elem,
-				      struct ieee80211_bss *bss);
+				      struct ieee80211_bss *bss,
+				      u64 timestamp);
 void ieee80211_sta_quiesce(struct ieee80211_sub_if_data *sdata);
 void ieee80211_sta_restart(struct ieee80211_sub_if_data *sdata);
 
diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c
index 358226f..f50d73f 100644
--- a/net/mac80211/mlme.c
+++ b/net/mac80211/mlme.c
@@ -340,7 +340,11 @@ static void ieee80211_chswitch_work(struct work_struct *work)
 		goto out;
 
 	sdata->local->oper_channel = sdata->local->csa_channel;
-	ieee80211_hw_config(sdata->local, IEEE80211_CONF_CHANGE_CHANNEL);
+	if (!sdata->local->ops->channel_switch) {
+		/* call "hw_config" only if doing sw channel switch */
+		ieee80211_hw_config(sdata->local,
+			IEEE80211_CONF_CHANGE_CHANNEL);
+	}
 
 	/* XXX: shouldn't really modify cfg80211-owned data! */
 	ifmgd->associated->channel = sdata->local->oper_channel;
@@ -352,6 +356,22 @@ static void ieee80211_chswitch_work(struct work_struct *work)
 	mutex_unlock(&ifmgd->mtx);
 }
 
+void ieee80211_chswitch_done(struct ieee80211_vif *vif, bool is_success)
+{
+	struct ieee80211_sub_if_data *sdata;
+	struct ieee80211_if_managed *ifmgd;
+
+	sdata = vif_to_sdata(vif);
+	ifmgd = &sdata->u.mgd;
+
+	trace_api_chswitch_done(sdata, is_success);
+	if (!is_success)
+		sdata->local->csa_channel = sdata->local->oper_channel;
+
+	ieee80211_queue_work(&sdata->local->hw, &ifmgd->chswitch_work);
+}
+EXPORT_SYMBOL(ieee80211_chswitch_done);
+
 static void ieee80211_chswitch_timer(unsigned long data)
 {
 	struct ieee80211_sub_if_data *sdata =
@@ -368,7 +388,8 @@ static void ieee80211_chswitch_timer(unsigned long data)
 
 void ieee80211_sta_process_chanswitch(struct ieee80211_sub_if_data *sdata,
 				      struct ieee80211_channel_sw_ie *sw_elem,
-				      struct ieee80211_bss *bss)
+				      struct ieee80211_bss *bss,
+				      u64 timestamp)
 {
 	struct cfg80211_bss *cbss =
 		container_of((void *)bss, struct cfg80211_bss, priv);
@@ -396,6 +417,23 @@ void ieee80211_sta_process_chanswitch(struct ieee80211_sub_if_data *sdata,
 
 	sdata->local->csa_channel = new_ch;
 
+	if (sdata->local->ops->channel_switch) {
+		/* use driver's channel switch callback */
+		struct ieee80211_channel_switch ch_switch;
+		memset(&ch_switch, 0, sizeof(ch_switch));
+		ch_switch.timestamp = timestamp;
+		if (sw_elem->mode) {
+			ch_switch.block_tx = true;
+			ieee80211_stop_queues_by_reason(&sdata->local->hw,
+					IEEE80211_QUEUE_STOP_REASON_CSA);
+		}
+		ch_switch.channel = new_ch;
+		ch_switch.count = sw_elem->count;
+		ifmgd->flags |= IEEE80211_STA_CSA_RECEIVED;
+		drv_channel_switch(sdata->local, &ch_switch);
+		return;
+	}
+	/* mac80211 handle channel switch */
 	if (sw_elem->count <= 1) {
 		ieee80211_queue_work(&sdata->local->hw, &ifmgd->chswitch_work);
 	} else {
@@ -1279,6 +1317,7 @@ static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata,
 	struct ieee80211_bss *bss;
 	struct ieee80211_channel *channel;
 	bool need_ps = false;
+	u64 timestamp;
 
 	if (sdata->u.mgd.associated) {
 		bss = (void *)sdata->u.mgd.associated->priv;
@@ -1315,7 +1354,12 @@ static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata,
 							ETH_ALEN) == 0)) {
 		struct ieee80211_channel_sw_ie *sw_elem =
 			(struct ieee80211_channel_sw_ie *)elems->ch_switch_elem;
-		ieee80211_sta_process_chanswitch(sdata, sw_elem, bss);
+		if (beacon)
+			timestamp = le64_to_cpu(mgmt->u.beacon.timestamp);
+		else
+			timestamp = le64_to_cpu(mgmt->u.probe_resp.timestamp);
+		ieee80211_sta_process_chanswitch(sdata, sw_elem,
+						 bss, timestamp);
 	}
 }
 
@@ -1647,7 +1691,8 @@ static void ieee80211_sta_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata,
 
 			ieee80211_sta_process_chanswitch(sdata,
 					&mgmt->u.action.u.chan_switch.sw_elem,
-					(void *)ifmgd->associated->priv);
+					(void *)ifmgd->associated->priv,
+					rx_status->mactime);
 			break;
 		}
 		mutex_unlock(&ifmgd->mtx);
-- 
1.5.6.3


^ permalink raw reply related	[flat|nested] 4+ messages in thread
end of thread, other threads:[~2010-05-06 14:09 UTC | newest]

Thread overview: 4+ messages (download: mbox.gz follow: Atom feed
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2010-05-06  3:34 [PATCH 1/2] mac80211: add offload channel switch support wey-yi.w.guy
2010-05-06  3:34 ` [PATCH 2/2] mac80211: check channel switch mode for future frames transmit wey-yi.w.guy
2010-05-06  7:44 ` [PATCH 1/2] mac80211: add offload channel switch support Johannes Berg
2010-05-06 14:09   ` Guy, Wey-Yi W

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