Merge pull request #2238 from particle-iot/fix/gen2_sleep20_blocked/ch68382

Gen2: platforms calling sleep20 API to enter stop/ulp mode may block user application.

Author: XuGuohui

hal/src/electron/modem/mdm_hal.cpp

@@ -1242,7 +1242,7 @@ void MDMParser::_incModemStateChangeCount(void) {
     }
 }
 
-int MDMParser::getModemStateChangeCount(void) {
+int MDMParser::getModemStateChangeCount(void) const {
     return _mdm_state_change_count;
 }
 
@@ -1253,6 +1253,13 @@ bool MDMParser::powerState(void) const {
         // We are definitely powered on
         return true;
     }
+    // RI is low (so the modem is probably off)
+    // Check whether modem has seen a state change at least once
+    // and current power state, that only gets reset if we've confirmed that
+    // modem was reset with a condition below.
+    if (getModemStateChangeCount() > 0 && !_pwr) {
+        return false;
+    }
     // We are still not sure whether we are off or not,
     // because RI may be held low for over a second under some conditions
     // Sleeping for 1.1s and checking again
@@ -1306,7 +1313,6 @@ bool MDMParser::powerOff(void)
     _resetFailureAttempts = 0;
     bool ok = false;
     bool continue_cancel = false;
-    bool check_ri = false;
 
     MDM_INFO("%s = = = = = = = = = = = = = =", POWER_OFF_MSG);
 
@@ -1315,7 +1321,8 @@ bool MDMParser::powerOff(void)
         resume(); // make sure we can use the AT parser
     }
 
-    check_ri = true;
+    bool power_state = true;
+
     if (!softPowerOff()) {
         if (_dev.dev == DEV_SARA_R410) {
             // If memory issue is present, ensure we don't force a power off too soon
@@ -1347,7 +1354,7 @@ bool MDMParser::powerOff(void)
             }
         }
         // Skip power off sequence if power is already off
-        if (powerState() && _dev.dev != DEV_SARA_G350) {
+        if (_dev.dev != DEV_SARA_G350 && (power_state = powerState())) {
             MDM_INFO("%s Modem not responsive, trying PWR_UC...", POWER_OFF_MSG);
             HAL_GPIO_Write(PWR_UC, 0);
             // >1.5 seconds on SARA R410M
@@ -1358,25 +1365,19 @@ bool MDMParser::powerOff(void)
         }
     }
 
-    // Verify power off, or delay
-    if (check_ri) {
-        system_tick_t t0 = HAL_Timer_Get_Milli_Seconds();
-        bool power_state = true;
-        while ((power_state = powerState()) && !TIMEOUT(t0, 15000)) {
-            HAL_Delay_Milliseconds(1); // just wait
-        }
-        // if V_INT is low, indicate power is off
-        if (!power_state) {
-            _pwr = false;
-            MDM_INFO("%s took %lu ms", POWER_OFF_MSG, HAL_Timer_Get_Milli_Seconds() - t0);
-        } else {
-            MDM_INFO("%s failed", POWER_OFF_MSG);
-        }
-    } else {
+    // Verify power off
+    system_tick_t t0 = HAL_Timer_Get_Milli_Seconds();
+    // NOTE: initial power_state value is checked here first
+    while (power_state && !TIMEOUT(t0, 15000)) {
+        HAL_Delay_Milliseconds(1); // just wait
+        power_state = powerState();
+    }
+    // if V_INT is low, indicate power is off
+    if (!power_state) {
         _pwr = false;
-        // todo - add if these are automatically done on power down
-        //_activated = false;
-        //_attached = false;
+        MDM_INFO("%s took %lu ms", POWER_OFF_MSG, HAL_Timer_Get_Milli_Seconds() - t0);
+    } else {
+        MDM_INFO("%s failed", POWER_OFF_MSG);
     }
     HAL_Delay_Milliseconds(1000); // give peace a chance
     // Increment the state change counter to show that the modem has been powered on -> off

hal/src/electron/modem/mdm_hal.h

@@ -152,7 +152,7 @@ class MDMParser
         which can be used to invalidate previous assumptions about the state of the modem.
         \return _pwr_off_count value
     */
-    int getModemStateChangeCount(void);
+    int getModemStateChangeCount(void) const;
 
     /** Power on the MT if necessary and then try powering off using AT command. This function has to be called prior to
         switching off the supply.

system/src/system_sleep.cpp

@@ -55,6 +55,11 @@ static bool system_sleep_network_suspend(network_interface_index index) {
         network_disconnect(index, NETWORK_DISCONNECT_REASON_SLEEP, NULL);
         resume = true;
     }
+#if PLATFORM_GEN == 2
+    if (!SPARK_WLAN_SLEEP) {
+        resume = true;
+    }
+#endif
     // Turn off the modem
     network_off(index, 0, 0, NULL);
     LOG(TRACE, "Waiting interface to be off...");
@@ -64,8 +69,16 @@ static bool system_sleep_network_suspend(network_interface_index index) {
 }
 
 static int system_sleep_network_resume(network_interface_index index) {
+#if PLATFORM_GEN == 2
+    /* On Gen2, calling network_on() and network_connect() will block until the connection is established
+     * if single threaded, or this function is invoked synchronously by the system thread if system threading
+     * is enabled. In both case, that would block the user application. Setting a flag here to unblock the user
+     * application and restore the connection later. */
+    SPARK_WLAN_SLEEP = 0;
+#else
     network_on(index, 0, 0, nullptr);
     network_connect(index, 0, 0, nullptr);
+#endif
     return SYSTEM_ERROR_NONE;
 }
 
@@ -183,7 +196,6 @@ int system_sleep_ext(const hal_sleep_config_t* config, hal_wakeup_source_base_t*
 
 #if HAL_PLATFORM_WIFI
     if (wifiResume) {
-        SPARK_WLAN_SLEEP = 0;
         system_sleep_network_resume(NETWORK_INTERFACE_WIFI_STA);
     }
 #endif // HAL_PLATFORM_WIFI

system/src/system_sleep_compat.cpp

@@ -171,8 +171,15 @@ int system_sleep_impl(Spark_Sleep_TypeDef sleepMode, long seconds, uint32_t para
                 RESET_REASON_NONE, seconds);
     }
 
+#if HAL_PLATFORM_SETUP_BUTTON_UX
+    bool networkTurnedOff = false;
+#endif // HAL_PLATFORM_SETUP_BUTTON_UX
+
     if (network_sleep_flag(param) || SLEEP_MODE_WLAN == sleepMode) {
         network_suspend();
+#if HAL_PLATFORM_SETUP_BUTTON_UX
+        networkTurnedOff = true;
+#endif // HAL_PLATFORM_SETUP_BUTTON_UX
     }
 
     switch (sleepMode)
@@ -193,17 +200,14 @@ int system_sleep_impl(Spark_Sleep_TypeDef sleepMode, long seconds, uint32_t para
             break;
 
         case SLEEP_MODE_DEEP:
-            if (network_sleep_flag(param))
-            {
-                network_disconnect(0, NETWORK_DISCONNECT_REASON_SLEEP, NULL);
-                network_off(0, 0, 0, NULL);
-            }
             return system_sleep_enter_standby_compat(seconds, param);
 
 #if HAL_PLATFORM_SETUP_BUTTON_UX
         case SLEEP_MODE_SOFTPOWEROFF:
-            network_disconnect(0, NETWORK_DISCONNECT_REASON_SLEEP, NULL);
-            network_off(0, 0, 0, NULL);
+            if (!networkTurnedOff) {
+                network_disconnect(0, NETWORK_DISCONNECT_REASON_SLEEP, NULL);
+                network_off(0, 0, 0, NULL);
+            }
             return system_sleep_enter_standby_compat(seconds, param);
 #endif
     }