Added documentation regarding requesting SED poll interval update. (#11521)

In the #11314
PR there were some post-merge comments regarding missing
documentation.

* Added missing documentation for the RequestSEDFastPollingMode
and SetSEDPollingConfig methods.
* Added setting new mode only if it's different than the current
one.

Author: kkasperczyk-no

src/include/platform/ConnectivityManager.h

@@ -216,7 +216,22 @@ class ConnectivityManager
 // Sleepy end device methods
 #if CHIP_DEVICE_CONFIG_ENABLE_SED
     CHIP_ERROR GetSEDPollingConfig(SEDPollingConfig & pollingConfig);
+
+    /**
+     * Sets Sleepy End Device polling configuration and posts kSEDPollingIntervalChange event to inform other software
+     * modules about the change.
+     *
+     * @param[in]  pollingConfig  polling intervals configuration to be set
+     */
     CHIP_ERROR SetSEDPollingConfig(const SEDPollingConfig & pollingConfig);
+
+    /**
+     * Requests setting Sleepy End Device fast polling interval on or off.
+     * Every method call with onOff parameter set to true or false results in incrementing or decrementing the fast polling
+     * consumers counter. Fast polling mode is set if the consumers counter is bigger than 0.
+     *
+     * @param[in]  onOff  true if fast polling should be enabled and false otherwise.
+     */
     CHIP_ERROR RequestSEDFastPollingMode(bool onOff);
 #endif
 

src/include/platform/ThreadStackManager.h

@@ -153,7 +153,22 @@ class ThreadStackManager
 
 #if CHIP_DEVICE_CONFIG_ENABLE_SED
     CHIP_ERROR GetSEDPollingConfig(ConnectivityManager::SEDPollingConfig & pollingConfig);
+
+    /**
+     * Sets Sleepy End Device polling configuration and posts kSEDPollingIntervalChange event to inform other software
+     * modules about the change.
+     *
+     * @param[in]  pollingConfig  polling intervals configuration to be set
+     */
     CHIP_ERROR SetSEDPollingConfig(const ConnectivityManager::SEDPollingConfig & pollingConfig);
+
+    /**
+     * Requests setting Sleepy End Device fast polling interval on or off.
+     * Every method call with onOff parameter set to true or false results in incrementing or decrementing the fast polling
+     * consumers counter. Fast polling mode is set if the consumers counter is bigger than 0.
+     *
+     * @param[in]  onOff  true if fast polling should be enabled and false otherwise.
+     */
     CHIP_ERROR RequestSEDFastPollingMode(bool onOff);
 #endif
 

src/messaging/ExchangeContext.cpp

@@ -84,9 +84,9 @@ void ExchangeContext::SetResponseTimeout(Timeout timeout)
 }
 
 #if CONFIG_DEVICE_LAYER && CHIP_DEVICE_CONFIG_ENABLE_SED
-void ExchangeContext::UpdateSEDPollingMode(Transport::Type transportType)
+void ExchangeContext::UpdateSEDPollingMode()
 {
-    if (transportType != Transport::Type::kBle)
+    if (GetSessionHandle().GetPeerAddress(mExchangeMgr->GetSessionManager())->GetTransportType() != Transport::Type::kBle)
     {
         if (!IsResponseExpected() && !IsSendExpected() && (mExchangeMgr->GetNumActiveExchanges() == 1))
         {
@@ -488,8 +488,7 @@ CHIP_ERROR ExchangeContext::HandleMessage(uint32_t messageCounter, const Payload
 void ExchangeContext::MessageHandled()
 {
 #if CONFIG_DEVICE_LAYER && CHIP_DEVICE_CONFIG_ENABLE_SED
-    const Transport::PeerAddress * peerAddress = GetSessionHandle().GetPeerAddress(mExchangeMgr->GetSessionManager());
-    UpdateSEDPollingMode(peerAddress->GetTransportType());
+    UpdateSEDPollingMode();
 #endif
 
     if (mFlags.Has(Flags::kFlagClosed) || IsResponseExpected() || IsSendExpected())

src/messaging/ExchangeContext.h

@@ -244,15 +244,11 @@ class DLL_EXPORT ExchangeContext : public ReliableMessageContext, public Referen
      * - set IDLE polling mode if all conditions are met:
      *   - device doesn't expect getting response nor sending message
      *   - there is no other active exchange than the current one
-     *   - active state is not forced (commissioning window is not opened)
      * - set ACTIVE polling mode if any of the conditions is met:
      *   - device expects getting response or sending message
      *   - there is another active exchange
-     *   - active state is forced (commissioning window is currently open)
-     *
-     * @param[in]  transportType  transport used by the exchange
      */
-    void UpdateSEDPollingMode(Transport::Type transportType);
+    void UpdateSEDPollingMode();
 };
 
 } // namespace Messaging

src/platform/OpenThread/GenericThreadStackManagerImpl_OpenThread.cpp

@@ -1468,7 +1468,7 @@ template <class ImplClass>
 CHIP_ERROR GenericThreadStackManagerImpl_OpenThread<ImplClass>::_RequestSEDFastPollingMode(bool onOff)
 {
     CHIP_ERROR err = CHIP_NO_ERROR;
-    uint32_t interval;
+    ConnectivityManager::SEDPollingMode mode;
 
     if (onOff)
     {
@@ -1480,14 +1480,10 @@ CHIP_ERROR GenericThreadStackManagerImpl_OpenThread<ImplClass>::_RequestSEDFastP
             mFastPollingConsumers--;
     }
 
-    if (mFastPollingConsumers > 0)
-    {
-        err = SetSEDPollingMode(ConnectivityManager::SEDPollingMode::Active);
-    }
-    else
-    {
-        err = SetSEDPollingMode(ConnectivityManager::SEDPollingMode::Idle);
-    }
+    mode = mFastPollingConsumers > 0 ? ConnectivityManager::SEDPollingMode::Active : ConnectivityManager::SEDPollingMode::Idle;
+
+    if (mPollingMode != mode)
+        err = SetSEDPollingMode(mode);
 
     return err;
 }