only poll when no transitions are active

satrs-example/src/acs/mgm.rs

@@ -264,8 +264,10 @@ impl MgmHandlerLis3Mdl {
             }
         }
 
-        // Poll sensor before checking and generating HK.
-        if self.mode() == DeviceMode::Normal {
+        // Poll sensor before checking and generating HK. The device is not polled during mode
+        // transitions, which includes all FDIR actions like power cycling or switching off a
+        // faulty device. Faults are expected then, and polling would only add noise.
+        if self.mode() == DeviceMode::Normal && self.switch_and_mode_helper.target().is_none() {
             log::trace!("polling LIS3MDL sensor {}", self.id.str());
             self.poll_sensor();
         }
@@ -486,10 +488,8 @@ impl MgmHandlerLis3Mdl {
     }
 
     fn switch_off_faulty_device(&mut self) {
-        // Do not restart an already pending Off transition: poll_sensor still calls
-        // this every cycle the fault persists, and current stays Normal until the
-        // transition completes, so re-triggering here would keep resetting the
-        // transition state machine before it can ever finish.
+        // Do not restart an already pending Off transition, which would reset the transition
+        // state machine before it can finish.
         if self.switch_and_mode_helper.target() != Some(DeviceMode::Off) {
             log::warn!("{}: commanding device off due to fault", self.id.str());
             self.start_transition(DeviceMode::Off, None);
@@ -1095,9 +1095,12 @@ mod tests {
         testbench.mode_report_rx.try_iter().for_each(drop);
         testbench.exceed_spi_fault_threshold();
         testbench.test_spi_interface().next_mgm_data = MgmLis3RawValues::default();
+        let call_count = testbench.test_spi_interface().call_count;
 
         testbench.complete_power_cycle();
 
+        // The device is only polled again once the power cycle is done.
+        assert_eq!(testbench.test_spi_interface().call_count, call_count + 1);
         // The power cycle is hidden from the parent.
         assert!(testbench.mode_report_rx.try_recv().is_err());
 
@@ -1144,15 +1147,17 @@ mod tests {
     }
 
     #[test]
-    fn test_faults_while_switching_off_keep_component_faulty() {
+    fn test_faulty_device_is_not_polled_while_switching_off() {
         let mut testbench = MgmTestbench::new();
         testbench.switch_to_normal();
         testbench.recover_until_faulty();
+        let call_count = testbench.test_spi_interface().call_count;
 
-        // The switch-off takes a while and the device is still polled in the meantime.
+        // The switch-off takes a while.
         for _ in 0..SPI_FAULT_THRESHOLD + 1 {
             testbench.handler.periodic_operation();
         }
+        assert_eq!(testbench.test_spi_interface().call_count, call_count);
         assert_eq!(testbench.health(), Some(HealthState::Faulty));
         testbench.set_switch_state(SwitchState::Off);
         testbench.handler.periodic_operation();