bricks/common/micropython: use transport type to select default stdio

Pass the transport type that requested the user program to start to
the MicroPython launcher to allow it to select the appropriate default
stdio stream (USB or Bluetooth).

Author: dlech

bricks/_common/micropython.c

@@ -7,6 +7,7 @@
 #include <stdio.h>
 #include <string.h>
 
+#include <pbdrv/bluetooth.h>
 #include <pbdrv/stack.h>
 
 #include <pbio/button.h>
@@ -391,11 +392,36 @@ void pbsys_main_run_program(pbsys_main_program_t *program) {
     mp_init();
 
     #if MICROPY_PY_SYS_MUTABLE_STDIO
-    // TODO: add logic to allow USB instead of Bluetooth
-    MP_STATE_VM(sys_mutable[MP_SYS_MUTABLE_STDIN]) = MP_OBJ_FROM_PTR(&pb_bluetooth_stdio_wrapper_obj);
-    MP_STATE_VM(sys_mutable[MP_SYS_MUTABLE_STDOUT]) = MP_OBJ_FROM_PTR(&pb_bluetooth_stdio_wrapper_obj);
-    MP_STATE_VM(sys_mutable[MP_SYS_MUTABLE_STDERR]) = MP_OBJ_FROM_PTR(&pb_bluetooth_stdio_wrapper_obj);
-    #endif
+
+    bool use_bluetooth;
+
+    // If the program was started remotely, use the same transport for stdio.
+    switch (program->start_request_type) {
+        case PBSYS_MAIN_PROGRAM_START_REQUEST_TYPE_BLUETOOTH:
+            use_bluetooth = true;
+            break;
+        case PBSYS_MAIN_PROGRAM_START_REQUEST_TYPE_USB:
+            use_bluetooth = false;
+            break;
+        default:
+            // Use Bluetooth if available, otherwise USB.
+            // REVISIT: might want to keep track of last used transport and use
+            // that instead.
+            use_bluetooth = pbdrv_bluetooth_is_connected(PBDRV_BLUETOOTH_CONNECTION_PYBRICKS);
+            break;
+    }
+
+    if (use_bluetooth) {
+        MP_STATE_VM(sys_mutable[MP_SYS_MUTABLE_STDIN]) = MP_OBJ_FROM_PTR(&pb_bluetooth_stdio_wrapper_obj);
+        MP_STATE_VM(sys_mutable[MP_SYS_MUTABLE_STDOUT]) = MP_OBJ_FROM_PTR(&pb_bluetooth_stdio_wrapper_obj);
+        MP_STATE_VM(sys_mutable[MP_SYS_MUTABLE_STDERR]) = MP_OBJ_FROM_PTR(&pb_bluetooth_stdio_wrapper_obj);
+    } else {
+        MP_STATE_VM(sys_mutable[MP_SYS_MUTABLE_STDIN]) = MP_OBJ_FROM_PTR(&pb_usb_stdio_wrapper_obj);
+        MP_STATE_VM(sys_mutable[MP_SYS_MUTABLE_STDOUT]) = MP_OBJ_FROM_PTR(&pb_usb_stdio_wrapper_obj);
+        MP_STATE_VM(sys_mutable[MP_SYS_MUTABLE_STDERR]) = MP_OBJ_FROM_PTR(&pb_usb_stdio_wrapper_obj);
+    }
+
+    #endif // MICROPY_PY_SYS_MUTABLE_STDIO
 
     // Runs the requested downloaded or builtin user program.
     switch (program->id) {

lib/pbio/include/pbsys/command.h

@@ -16,10 +16,13 @@
 #include <stdint.h>
 
 #include <pbio/protocol.h>
+#include <pbsys/main.h>
 
 typedef enum {
-    PBSYS_COMMAND_TRANSPORT_BLE,
-    PBSYS_COMMAND_TRANSPORT_USB,
+    // NB: these values allow passing pbsys_command_transport_t directly as
+    // pbsys_main_program_start_request_type_t without a lookup table.
+    PBSYS_COMMAND_TRANSPORT_BLE = PBSYS_MAIN_PROGRAM_START_REQUEST_TYPE_BLUETOOTH,
+    PBSYS_COMMAND_TRANSPORT_USB = PBSYS_MAIN_PROGRAM_START_REQUEST_TYPE_USB,
 } pbsys_command_transport_t;
 
 pbio_pybricks_error_t pbsys_command(const uint8_t *data, uint32_t size, pbsys_command_transport_t transport);

lib/pbio/include/pbsys/main.h

@@ -36,8 +36,18 @@ typedef enum {
     PBSYS_MAIN_PROGRAM_START_REQUEST_TYPE_HUB_UI = 2,
     /**
      * The program was requested to start remotely, such as with an IDE.
+     *
+     * @deprecated Use transport-specific items instead.
      */
     PBSYS_MAIN_PROGRAM_START_REQUEST_TYPE_REMOTE = 3,
+    /**
+     * The program was requested to start using Bluetooth.
+     */
+    PBSYS_MAIN_PROGRAM_START_REQUEST_TYPE_BLUETOOTH = 4,
+    /**
+     * The program was requested to start using USB.
+     */
+    PBSYS_MAIN_PROGRAM_START_REQUEST_TYPE_USB = 5,
 } pbsys_main_program_start_request_type_t;
 
 /**

lib/pbio/sys/command.c

@@ -51,14 +51,14 @@ pbio_pybricks_error_t pbsys_command(const uint8_t *data, uint32_t size, pbsys_co
             }
             // Use payload as program ID, otherwise use active user slot.
             return pbio_pybricks_error_from_pbio_error(
-                pbsys_main_program_request_start((size == 2 ? data[1] : pbsys_hmi_get_selected_program_slot()), PBSYS_MAIN_PROGRAM_START_REQUEST_TYPE_REMOTE));
+                pbsys_main_program_request_start((size == 2 ? data[1] : pbsys_hmi_get_selected_program_slot()), (pbsys_main_program_start_request_type_t)transport));
         }
         #if PBSYS_CONFIG_FEATURE_BUILTIN_USER_PROGRAM_REPL
         case PBIO_PYBRICKS_COMMAND_START_REPL:
             // Deprecated. For backwards compatibility with Pybricks
             // Profile < v1.4.0, make it work anyway.
             return pbio_pybricks_error_from_pbio_error(
-                pbsys_main_program_request_start(PBIO_PYBRICKS_USER_PROGRAM_ID_REPL, PBSYS_MAIN_PROGRAM_START_REQUEST_TYPE_REMOTE));
+                pbsys_main_program_request_start(PBIO_PYBRICKS_USER_PROGRAM_ID_REPL, (pbsys_main_program_start_request_type_t)transport));
         #endif // PBSYS_CONFIG_FEATURE_BUILTIN_USER_PROGRAM_REPL
 
         case PBIO_PYBRICKS_COMMAND_WRITE_USER_PROGRAM_META: