[ICD] Add read handler callback to negociate max sub interval (#24414)

* add max interval negociation

* generic read handler

* restyle

* Address PR comments

* Update naming used

* Update gn argument name

* Add class / function comments

* Add an ICD build to efr32 workflow

* Apply suggestions from code review

Co-authored-by: Boris Zbarsky <bzbarsky@apple.com>

* Address PR comments

* restyle

* Add fail safe checks to always have a valid maxInterval

* PR comments

Co-authored-by: Boris Zbarsky <bzbarsky@apple.com>

.github/workflows/examples-efr32.yaml

@@ -82,6 +82,7 @@ jobs:
                 --enable-flashbundle \
                 --target efr32-brd4187c-window-covering \
                 --target efr32-brd4187c-switch \
+                --target efr32-brd4187c-switch-sed \
                 --target efr32-brd4187c-unit-test \
                 --target efr32-brd4187c-light \
                 --target efr32-brd4187c-light-rpc \

examples/light-switch-app/silabs/efr32/BUILD.gn

@@ -74,11 +74,17 @@ declare_args() {
 declare_args() {
   # Enables LCD Qr Code on supported devices
   show_qr_code = !disable_lcd
+
+  # Use default handler to negotiate subscription max interval
+  chip_config_use_icd_subscription_callbacks = enable_sleepy_device
 }
 
 # qr code cannot be true if lcd is disabled
 assert(!(disable_lcd && show_qr_code))
 
+# default read handler cannot be used without being an IC device (SED)
+assert(!chip_config_use_icd_subscription_callbacks || enable_sleepy_device)
+
 # Sanity check
 assert(!(chip_enable_wifi && chip_enable_openthread))
 assert(!(use_rs911x && chip_enable_openthread))
@@ -252,6 +258,11 @@ efr32_executable("light_switch_app") {
     deps += [ "${examples_plat_dir}:efr32-factory-data-provider" ]
   }
 
+  # Default Read handler for SED
+  if (chip_config_use_icd_subscription_callbacks) {
+    deps += [ "${examples_plat_dir}:efr32-ICD-subscription-callback" ]
+  }
+
   if (chip_enable_ota_requestor) {
     defines += [ "EFR32_OTA_ENABLED" ]
     sources += [ "${examples_plat_dir}/OTAConfig.cpp" ]

examples/platform/silabs/ICDSubscriptionCallback.cpp

@@ -0,0 +1,65 @@
+/*
+ *
+ *    Copyright (c) 2023 Project CHIP Authors
+ *    All rights reserved.
+ *
+ *    Licensed under the Apache License, Version 2.0 (the "License");
+ *    you may not use this file except in compliance with the License.
+ *    You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *    Unless required by applicable law or agreed to in writing, software
+ *    distributed under the License is distributed on an "AS IS" BASIS,
+ *    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *    See the License for the specific language governing permissions and
+ *    limitations under the License.
+ */
+
+#include "ICDSubscriptionCallback.h"
+#include <platform/CHIPDeviceConfig.h>
+
+CHIP_ERROR ICDSubscriptionCallback::OnSubscriptionRequested(chip::app::ReadHandler & aReadHandler,
+                                                            chip::Transport::SecureSession & aSecureSession)
+{
+    using namespace chip::System::Clock;
+
+    Seconds32 interval_s32 = std::chrono::duration_cast<Seconds32>(CHIP_DEVICE_CONFIG_SED_IDLE_INTERVAL);
+
+    if (interval_s32 > Seconds16::max())
+    {
+        interval_s32 = Seconds16::max();
+    }
+    uint32_t decidedMaxInterval = interval_s32.count();
+
+    uint16_t requestedMinInterval = 0;
+    uint16_t requestedMaxInterval = 0;
+    aReadHandler.GetReportingIntervals(requestedMinInterval, requestedMaxInterval);
+
+    // If requestedMinInterval is greater than IdleTimeInterval, select next wake up time as max interval
+    if (requestedMinInterval > decidedMaxInterval)
+    {
+        uint16_t ratio = requestedMinInterval / decidedMaxInterval;
+        if (requestedMinInterval % decidedMaxInterval)
+        {
+            ratio++;
+        }
+
+        decidedMaxInterval *= ratio;
+    }
+
+    // Verify that decidedMaxInterval is an acceptable value
+    if (decidedMaxInterval > Seconds16::max().count())
+    {
+        decidedMaxInterval = Seconds16::max().count();
+    }
+
+    // Verify that the decidedMaxInterval respects MAX(SUBSCRIPTION_MAX_INTERVAL_PUBLISHER_LIMIT, MaxIntervalCeiling)
+    uint16_t maximumMaxInterval = std::max(kSubscriptionMaxIntervalPublisherLimit, requestedMaxInterval);
+    if (decidedMaxInterval > maximumMaxInterval)
+    {
+        decidedMaxInterval = maximumMaxInterval;
+    }
+
+    return aReadHandler.SetReportingIntervals(decidedMaxInterval);
+}

examples/platform/silabs/ICDSubscriptionCallback.h

@@ -0,0 +1,35 @@
+/*
+ *
+ *    Copyright (c) 2023 Project CHIP Authors
+ *    All rights reserved.
+ *
+ *    Licensed under the Apache License, Version 2.0 (the "License");
+ *    you may not use this file except in compliance with the License.
+ *    You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *    Unless required by applicable law or agreed to in writing, software
+ *    distributed under the License is distributed on an "AS IS" BASIS,
+ *    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *    See the License for the specific language governing permissions and
+ *    limitations under the License.
+ */
+#pragma once
+
+#include <app/ReadHandler.h>
+
+/**
+ * @brief The goal of the ICDSubscriptionCallback class is to negotiate the max interval subscription to match the idle interval of
+ * the IC device. When a subscription is requested, the device will change the requested max interval to match its idle time
+ * interval through the OnSubscriptionRequested function.
+ */
+class ICDSubscriptionCallback : public chip::app::ReadHandler::ApplicationCallback
+{
+    /**
+     * @brief Function called when a subscription is requested.
+     *        An ICD will use this function to negotiate the subscription max interval to match its idle time interval
+     */
+    CHIP_ERROR OnSubscriptionRequested(chip::app::ReadHandler & aReadHandler,
+                                       chip::Transport::SecureSession & aSecureSession) override;
+};

examples/platform/silabs/efr32/BUILD.gn

@@ -110,6 +110,19 @@ source_set("efr32-factory-data-provider") {
     "${chip_root}/src/platform:platform_base",
     "${chip_root}/src/setup_payload",
   ]
+}
+
+config("ICD-subscription-callback-config") {
+  defines = [ "CHIP_CONFIG_USE_ICD_SUBSCRIPTION_CALLBACKS=1" ]
+}
+
+source_set("efr32-ICD-subscription-callback") {
+  sources = [
+    "../ICDSubscriptionCallback.cpp",
+    "../ICDSubscriptionCallback.h",
+  ]
+
+  public_deps = [ "${chip_root}/src/app:app" ]
 
-  #public_configs = [ "" ]
+  public_configs = [ ":ICD-subscription-callback-config" ]
 }

examples/platform/silabs/efr32/matter_config.cpp

@@ -54,6 +54,11 @@ static chip::DeviceLayer::Internal::Efr32PsaOperationalKeystore gOperationalKeys
 #endif
 
 #include "EFR32DeviceDataProvider.h"
+#include <app/InteractionModelEngine.h>
+
+#ifdef CHIP_CONFIG_USE_ICD_SUBSCRIPTION_CALLBACKS
+ICDSubscriptionCallback EFR32MatterConfig::mICDSubscriptionHandler;
+#endif // CHIP_CONFIG_USE_ICD_SUBSCRIPTION_CALLBACKS
 
 #if CHIP_ENABLE_OPENTHREAD
 #include <inet/EndPointStateOpenThread.h>
@@ -189,6 +194,12 @@ CHIP_ERROR EFR32MatterConfig::InitMatter(const char * appName)
 
     // Init Matter Server and Start Event Loop
     err = chip::Server::GetInstance().Init(initParams);
+
+#ifdef CHIP_CONFIG_USE_ICD_SUBSCRIPTION_CALLBACKS
+    // Register ICD subscription callback to match subscription max intervals to its idle time interval
+    chip::app::InteractionModelEngine::GetInstance()->RegisterReadHandlerAppCallback(&mICDSubscriptionHandler);
+#endif // CHIP_CONFIG_USE_ICD_SUBSCRIPTION_CALLBACKS
+
     chip::DeviceLayer::PlatformMgr().UnlockChipStack();
 
     ReturnErrorOnFailure(err);

examples/platform/silabs/efr32/matter_config.h

@@ -22,6 +22,10 @@
 #include <platform/CHIPDeviceLayer.h>
 #include <platform/KeyValueStoreManager.h>
 
+#ifdef CHIP_CONFIG_USE_ICD_SUBSCRIPTION_CALLBACKS
+#include "ICDSubscriptionCallback.h"
+#endif // CHIP_CONFIG_USE_ICD_SUBSCRIPTION_CALLBACKS
+
 class EFR32MatterConfig
 {
 public:
@@ -32,4 +36,8 @@ class EFR32MatterConfig
     static void InitWiFi(void);
     static void ConnectivityEventCallback(const chip::DeviceLayer::ChipDeviceEvent * event, intptr_t arg);
     static void InitOTARequestorHandler(chip::System::Layer * systemLayer, void * appState);
+
+#ifdef CHIP_CONFIG_USE_ICD_SUBSCRIPTION_CALLBACKS
+    static ICDSubscriptionCallback mICDSubscriptionHandler;
+#endif // CHIP_CONFIG_USE_ICD_SUBSCRIPTION_CALLBACKS
 };