pybricks: Unify deinit by queueing noop task.

Author: laurensvalk

lib/pbio/drv/bluetooth/bluetooth_btstack.c

@@ -629,6 +629,16 @@ const char *pbdrv_bluetooth_get_fw_version(void) {
     return "v1.4";
 }
 
+static PT_THREAD(noop_task(struct pt *pt, pbio_task_t *task)) {
+    PT_BEGIN(pt);
+    task->status = PBIO_SUCCESS;
+    PT_END(pt);
+}
+
+void pbdrv_bluetooth_queue_noop(pbio_task_t *task) {
+    start_task(task, noop_task, NULL);
+}
+
 static void init_advertising_data(void) {
     bd_addr_t null_addr = { };
     gap_advertisements_set_params(0x30, 0x30, PBDRV_BLUETOOTH_AD_TYPE_ADV_IND, 0x00, null_addr, 0x07, 0x00);

lib/pbio/drv/bluetooth/bluetooth_stm32_bluenrg.c

@@ -259,6 +259,16 @@ const char *pbdrv_bluetooth_get_fw_version(void) {
     return pbdrv_bluetooth_fw_version;
 }
 
+static PT_THREAD(noop_task(struct pt *pt, pbio_task_t *task)) {
+    PT_BEGIN(pt);
+    task->status = PBIO_SUCCESS;
+    PT_END(pt);
+}
+
+void pbdrv_bluetooth_queue_noop(pbio_task_t *task) {
+    start_task(task, noop_task, NULL);
+}
+
 /**
  * Sets advertising data and enables advertisements.
  */

lib/pbio/drv/bluetooth/bluetooth_stm32_cc2640.c

@@ -294,6 +294,16 @@ const char *pbdrv_bluetooth_get_fw_version(void) {
     return pbdrv_bluetooth_fw_version;
 }
 
+static PT_THREAD(noop_task(struct pt *pt, pbio_task_t *task)) {
+    PT_BEGIN(pt);
+    task->status = PBIO_SUCCESS;
+    PT_END(pt);
+}
+
+void pbdrv_bluetooth_queue_noop(pbio_task_t *task) {
+    start_task(task, noop_task, NULL);
+}
+
 /**
  * Sets advertising data and enables advertisements.
  */

lib/pbio/include/pbdrv/bluetooth.h

@@ -240,6 +240,12 @@ const char *pbdrv_bluetooth_get_hub_name(void);
  */
 const char *pbdrv_bluetooth_get_fw_version(void);
 
+/**
+ * Queues a task that does nothing. When this task completes, all tasks
+ * before it will have finished or failed.
+ */
+void pbdrv_bluetooth_queue_noop(pbio_task_t *task);
+
 /**
  * Starts the advertising process, including configuring advertisements and
  * telling the Bluetooth chip to start advertising. Advertising should
@@ -394,6 +400,9 @@ static inline const char *pbdrv_bluetooth_get_fw_version(void) {
     return "";
 }
 
+static inline void pbdrv_bluetooth_queue_noop(pbio_task_t *task) {
+}
+
 static inline void pbdrv_bluetooth_start_advertising(void) {
 }
 

pybricks/common.h

@@ -31,7 +31,7 @@ void pb_package_pybricks_deinit(void);
 
 #if PYBRICKS_PY_COMMON_BLE
 mp_obj_t pb_type_BLE_new(mp_obj_t broadcast_channel_in, mp_obj_t observe_channels_in);
-void pb_type_BLE_cleanup(void);
+void pb_type_ble_start_cleanup(void);
 #endif
 
 #if PYBRICKS_PY_COMMON_CHARGER

pybricks/common/pb_type_ble.c

@@ -502,15 +502,15 @@ STATIC MP_DEFINE_CONST_OBJ_TYPE(pb_type_BLE,
 /**
  * Creates a new instance of the BLE class.
  *
- * Do not call this function more than once unless pb_type_BLE_cleanup() is called first.
+ * Do not call this function more than once unless pb_type_ble_start_cleanup() is called first.
  *
  * @param [in]  broadcast_channel_in    (int) The channel number to use for broadcasting.
  * @param [in]  observe_channels_in     (list[int]) A list of channels numbers to observe.
  * @returns                             A newly allocated object.
  * @throws ValueError                   If either parameter contains an out of range channel number.
  */
 mp_obj_t pb_type_BLE_new(mp_obj_t broadcast_channel_in, mp_obj_t observe_channels_in) {
-    // making the assumption that this is only called once before each pb_type_BLE_cleanup()
+    // making the assumption that this is only called once before each pb_type_ble_start_cleanup()
     assert(observed_data == NULL);
 
     mp_int_t broadcast_channel = mp_obj_get_int(broadcast_channel_in);
@@ -558,17 +558,14 @@ mp_obj_t pb_type_BLE_new(mp_obj_t broadcast_channel_in, mp_obj_t observe_channel
     return MP_OBJ_FROM_PTR(self);
 }
 
-void pb_type_BLE_cleanup(void) {
+void pb_type_ble_start_cleanup(void) {
     static pbio_task_t stop_broadcasting_task;
     static pbio_task_t stop_observing_task;
     pbdrv_bluetooth_stop_broadcasting(&stop_broadcasting_task);
     pbdrv_bluetooth_stop_observing(&stop_observing_task);
     observed_data = NULL;
     num_observed_data = 0;
-
-    while (stop_broadcasting_task.status == PBIO_ERROR_AGAIN || stop_observing_task.status == PBIO_ERROR_AGAIN) {
-        MICROPY_VM_HOOK_LOOP
-    }
+    // Tasks awaited in pybricks de-init.
 }
 
 #endif // PYBRICKS_PY_COMMON_BLE

pybricks/iodevices/pb_type_iodevices_lwp3device.c

@@ -321,13 +321,10 @@ STATIC void pb_lwp3device_configure_remote(void) {
     }
 }
 
-void pb_type_Remote_cleanup(void) {
+void pb_type_lwp3device_start_cleanup(void) {
     static pbio_task_t disconnect_task;
     pbdrv_bluetooth_peripheral_disconnect(&disconnect_task);
-
-    while (disconnect_task.status == PBIO_ERROR_AGAIN) {
-        MICROPY_EVENT_POLL_HOOK
-    }
+    // Task awaited in pybricks de-init.
 }
 
 mp_obj_t pb_type_remote_button_pressed(void) {

pybricks/pupdevices.h

@@ -27,7 +27,7 @@ extern const mp_obj_type_t pb_type_pupdevices_TiltSensor;
 extern const mp_obj_type_t pb_type_pupdevices_UltrasonicSensor;
 
 pb_type_device_obj_base_t *pupdevices_ColorDistanceSensor__get_device(mp_obj_t obj);
-void pb_type_Remote_cleanup(void);
+void pb_type_lwp3device_start_cleanup(void);
 
 #endif // PYBRICKS_PY_PUPDEVICES
 

pybricks/pybricks.c

@@ -10,6 +10,7 @@
 #include "py/objtuple.h"
 #include "py/runtime.h"
 
+#include <pbdrv/bluetooth.h>
 #include <pbio/version.h>
 
 #include <pybricks/common.h>
@@ -133,10 +134,20 @@ void pb_package_pybricks_init(bool import_all) {
 // REVISIT: move these to object finalizers if we enable finalizers in the GC
 void pb_package_pybricks_deinit(void) {
     #if PYBRICKS_PY_COMMON_BLE
-    pb_type_BLE_cleanup();
+    pb_type_ble_start_cleanup();
     #endif
     // Disconnect from remote.
     #if PYBRICKS_PY_PUPDEVICES
-    pb_type_Remote_cleanup();
+    pb_type_lwp3device_start_cleanup();
     #endif // PYBRICKS_PY_PUPDEVICES
+
+    #if PYBRICKS_PY_COMMON_BLE && PYBRICKS_PY_PUPDEVICES
+    // By queueing and awaiting a task that does nothing, we know that all user
+    // tasks and deinit tasks have completed.
+    static pbio_task_t noop_task;
+    pbdrv_bluetooth_queue_noop(&noop_task);
+    while (noop_task.status == PBIO_ERROR_AGAIN) {
+        MICROPY_VM_HOOK_LOOP
+    }
+    #endif
 }