[icd] Introduced define to configure the slow poll limit for SIT

The slow poll interval limit for SIT is by spec set to 15 s.
This value is used for LIT device working as a SIT, but in
some cases it could be beneficial to be able to change this
limit to the smaller value.

Author: kkasperczyk-no

config/nrfconnect/chip-module/CMakeLists.txt

@@ -147,6 +147,7 @@ if (CONFIG_CHIP_ENABLE_ICD_SUPPORT)
     matter_add_gn_arg_bool  ("chip_enable_icd_lit"                       CONFIG_CHIP_ICD_LIT_SUPPORT)
     matter_add_gn_arg_bool  ("chip_enable_icd_checkin"                   CONFIG_CHIP_ICD_CHECK_IN_SUPPORT)
     matter_add_gn_arg_bool  ("chip_enable_icd_user_active_mode_trigger"  CONFIG_CHIP_ICD_UAT_SUPPORT)
+    matter_add_gn_arg_bool  ("icd_enforce_sit_slow_poll_limit"           TRUE)
 endif()
 
 if (CONFIG_CHIP_FACTORY_DATA OR CONFIG_CHIP_FACTORY_DATA_CUSTOM_BACKEND)

config/zephyr/Kconfig

@@ -354,6 +354,15 @@ config CHIP_ICD_SLOW_POLL_INTERVAL
 	  device is in the idle mode. It determines the fastest frequency at which the device will be able
 	  to receive the messages in the idle mode.
 
+config CHIP_ICD_SIT_SLOW_POLL_LIMIT
+	int "Intermittently Connected Device slow polling interval limit for device in SIT mode (ms)"
+	default 15000
+	range 0 15000
+	help
+	  Provides the limit for Intermittently Connected Device slow polling interval in milliseconds while the
+	  device is in the SIT mode. By spec, this value cannot exceed 15 s (spec 9.16.1.5). This value can be
+	  used for the LIT device, to limit the slow poll interval used while temporarily working in the SIT mode.
+
 config CHIP_ICD_FAST_POLLING_INTERVAL
 	int "Intermittently Connected Device fast polling interval (ms)"
 	default 200

src/app/icd/server/ICDConfigurationData.h

@@ -159,7 +159,9 @@ class ICDConfigurationData
     System::Clock::Seconds32 mMaximumCheckInBackOff = System::Clock::Seconds32(CHIP_CONFIG_ICD_MAXIMUM_CHECK_IN_BACKOFF_SEC);
 
     // SIT ICDs should have a SlowPollingThreshold shorter than or equal to 15s (spec 9.16.1.5)
-    static constexpr System::Clock::Milliseconds32 kSITPollingThreshold = System::Clock::Milliseconds32(15000);
+    static_assert((CHIP_DEVICE_CONFIG_ICD_SIT_SLOW_POLL_LIMIT).count() <= 15000,
+                  "Spec requires the maximum slow poll interval for the SIT device to be smaller or equal than 15 s.");
+    static constexpr System::Clock::Milliseconds32 kSITPollingThreshold = CHIP_DEVICE_CONFIG_ICD_SIT_SLOW_POLL_LIMIT;
     System::Clock::Milliseconds32 mSlowPollingInterval                  = CHIP_DEVICE_CONFIG_ICD_SLOW_POLL_INTERVAL;
     System::Clock::Milliseconds32 mFastPollingInterval                  = CHIP_DEVICE_CONFIG_ICD_FAST_POLL_INTERVAL;
 

src/include/platform/CHIPDeviceConfig.h

@@ -146,6 +146,19 @@
 #define CHIP_DEVICE_CONFIG_ICD_SLOW_POLL_INTERVAL System::Clock::Milliseconds32(5000)
 #endif
 
+/**
+ * CHIP_DEVICE_CONFIG_ICD_SIT_SLOW_POLL_LIMIT
+ *
+ * The maximum value of time in milliseconds that the sleepy end device can use as an idle interval in the SIT mode.
+ * The Matter spec does not allow this value to exceed 15s (spec 9.16.1.5).
+ * For the SIT device, the usability of this value is arguable, as slow poll interval can be configured using
+ * CHIP_DEVICE_CONFIG_ICD_SLOW_POLL_INTERVAL. This value can be used for the LIT device, to limit the slow poll interval used while
+ * temporarily working in the SIT mode.
+ */
+#ifndef CHIP_DEVICE_CONFIG_ICD_SIT_SLOW_POLL_LIMIT
+#define CHIP_DEVICE_CONFIG_ICD_SIT_SLOW_POLL_LIMIT System::Clock::Milliseconds32(15000)
+#endif
+
 /**
  * CHIP_DEVICE_CONFIG_ICD_FAST_POLL_INTERVAL
  *

src/platform/nrfconnect/CHIPDevicePlatformConfig.h

@@ -221,6 +221,12 @@
 #endif // CONFIG_CHIP_ICD_SLOW_POLL_INTERVAL
 #endif // CHIP_DEVICE_CONFIG_ICD_SLOW_POLL_INTERVAL
 
+#ifndef CHIP_DEVICE_CONFIG_ICD_SIT_SLOW_POLL_LIMIT
+#ifdef CONFIG_CHIP_ICD_SIT_SLOW_POLL_LIMIT
+#define CHIP_DEVICE_CONFIG_ICD_SIT_SLOW_POLL_LIMIT chip::System::Clock::Milliseconds32(CONFIG_CHIP_ICD_SIT_SLOW_POLL_LIMIT)
+#endif // CONFIG_CHIP_ICD_SIT_SLOW_POLL_LIMIT
+#endif // CHIP_DEVICE_CONFIG_ICD_SIT_SLOW_POLL_LIMIT
+
 #ifndef CHIP_DEVICE_CONFIG_ICD_FAST_POLL_INTERVAL
 #ifdef CONFIG_CHIP_ICD_FAST_POLLING_INTERVAL
 #define CHIP_DEVICE_CONFIG_ICD_FAST_POLL_INTERVAL chip::System::Clock::Milliseconds32(CONFIG_CHIP_ICD_FAST_POLLING_INTERVAL)