pbio/sys/light_matrix: Centralize shutdown logic.

Since pbsys has a graceful exit point, start shutdown animations from there instead of relying on changing statuses in special ways that avoid race conditions.

Author: laurensvalk

lib/pbio/sys/core.c

@@ -13,6 +13,7 @@
 #include "core.h"
 #include "hmi.h"
 #include "light.h"
+#include "light_matrix.h"
 #include "storage.h"
 #include "supervisor.h"
 #include "program_stop.h"
@@ -58,6 +59,7 @@ void pbsys_init(void) {
 void pbsys_deinit(void) {
 
     pbsys_storage_deinit();
+    pbsys_hub_light_matrix_deinit();
 
     uint32_t start = pbdrv_clock_get_ms();
 

lib/pbio/sys/light_matrix.c

@@ -101,6 +101,11 @@ void pbsys_hub_light_matrix_init(void) {
     pbsys_hub_light_matrix_start_power_animation();
 }
 
+void pbsys_hub_light_matrix_deinit(void) {
+    // Starting it again continues it in reverse.
+    pbsys_hub_light_matrix_start_power_animation();
+}
+
 /**
  * Clears the pixels needed for the run animation
  */
@@ -139,35 +144,23 @@ static uint32_t pbsys_hub_light_matrix_user_program_animation_next(pbio_light_an
 }
 
 void pbsys_hub_light_matrix_handle_status_change(pbsys_status_change_t event, pbio_pybricks_status_t data) {
+
+    pbio_pybricks_status_t status = (intptr_t)data;
+
+    // Only need to handle changing program running state.
+    if (status != PBIO_PYBRICKS_STATUS_USER_PROGRAM_RUNNING) {
+        return;
+    }
+
     if (event == PBSYS_STATUS_CHANGE_SET) {
-        pbio_pybricks_status_t status = (intptr_t)data;
-
-        if (status == PBIO_PYBRICKS_STATUS_USER_PROGRAM_RUNNING) {
-            // The user animation updates only a subset of pixels to save time,
-            // so the rest must be cleared before it starts.
-            pbsys_hub_light_matrix_user_program_animation_clear();
-            pbio_light_animation_init(&pbsys_hub_light_matrix->animation, pbsys_hub_light_matrix_user_program_animation_next);
-            pbio_light_animation_start(&pbsys_hub_light_matrix->animation);
-        } else if (status == PBIO_PYBRICKS_STATUS_SHUTDOWN_REQUEST && !pbsys_status_test(PBIO_PYBRICKS_STATUS_USER_PROGRAM_RUNNING)) {
-            // If shutdown was requested and no program is running, start power
-            // down animation. This makes it run while the system processes are
-            // deinitializing. If it was running, we should wait for it to end
-            // first, which is handled below to avoid a race condition.
-            pbsys_hub_light_matrix_start_power_animation();
-        }
+        // The user animation updates only a subset of pixels to save time,
+        // so the rest must be cleared before it starts.
+        pbsys_hub_light_matrix_user_program_animation_clear();
+        pbio_light_animation_init(&pbsys_hub_light_matrix->animation, pbsys_hub_light_matrix_user_program_animation_next);
+        pbio_light_animation_start(&pbsys_hub_light_matrix->animation);
     } else if (event == PBSYS_STATUS_CHANGE_CLEARED) {
-        pbio_pybricks_status_t status = (intptr_t)data;
-
-        // The user program has ended.
-        if (status == PBIO_PYBRICKS_STATUS_USER_PROGRAM_RUNNING) {
-            if (pbsys_status_test(PBIO_PYBRICKS_STATUS_SHUTDOWN_REQUEST)) {
-                // If it ended due to forced shutdown, show power-off animation.
-                pbsys_hub_light_matrix_start_power_animation();
-            } else {
-                // If it simply completed, show stop sign and selected slot.
-                pbsys_hub_light_matrix_show_idle_ui(100);
-            }
-        }
+        // If the user program has ended, show stop sign and selected slot.
+        pbsys_hub_light_matrix_show_idle_ui(100);
     }
 }
 

lib/pbio/sys/light_matrix.h

@@ -10,10 +10,12 @@
 
 #if PBSYS_CONFIG_HUB_LIGHT_MATRIX
 void pbsys_hub_light_matrix_init(void);
+void pbsys_hub_light_matrix_deinit(void);
 void pbsys_hub_light_matrix_handle_status_change(pbsys_status_change_t event, pbio_pybricks_status_t data);
 void pbsys_hub_light_matrix_update_program_slot(void);
 #else
 #define pbsys_hub_light_matrix_init()
+#define pbsys_hub_light_matrix_deinit()
 #define pbsys_hub_light_matrix_handle_status_change(event, data)
 #define pbsys_hub_light_matrix_update_program_slot()
 #endif

lib/pbio/sys/main.c

@@ -120,6 +120,11 @@ int main(int argc, char **argv) {
         pbsys_program_stop_set_buttons(PBIO_BUTTON_CENTER);
         pbio_stop_all(true);
         program.start_request_type = PBSYS_MAIN_PROGRAM_START_REQUEST_TYPE_NONE;
+
+        // Handle pending events triggered by the status change, such as
+        // stopping status light animation.
+        while (pbio_os_run_processes_once()) {
+        }
     }
 
     // Power off sensors and motors, including the ones that are always powered.