ESP32-S3 BLE: set up Characteristic properly during discovery

Author: dhalbert

ports/espressif/common-hal/_bleio/Adapter.c

@@ -284,15 +284,21 @@ STATIC void _new_connection(uint16_t conn_handle) {
     esp_ble_tx_power_set(conn_handle, ESP_PWR_LVL_N0);
 
 
-    // Find an empty connection. One must always be available because the SD has the same
+    // Find an empty connection. One should always be available because the SD has the same
     // total connection limit.
-    bleio_connection_internal_t *connection;
+    bleio_connection_internal_t *connection = NULL;
     for (size_t i = 0; i < BLEIO_TOTAL_CONNECTION_COUNT; i++) {
         connection = &bleio_connections[i];
         if (connection->conn_handle == BLEIO_HANDLE_INVALID) {
             break;
         }
     }
+
+    // Shouldn't happen, but just return if no connection available.
+    if (!connection) {
+        return;
+    }
+
     connection->conn_handle = conn_handle;
     connection->connection_obj = mp_const_none;
     connection->pair_status = PAIR_NOT_PAIRED;

ports/espressif/common-hal/_bleio/Characteristic.c

@@ -50,7 +50,25 @@ void common_hal_bleio_characteristic_construct(bleio_characteristic_obj_t *self,
     self->props = props;
     self->read_perm = read_perm;
     self->write_perm = write_perm;
-    common_hal_bleio_characteristic_set_value(self, initial_value_bufinfo);
+
+    if (initial_value_bufinfo != NULL) {
+        // Copy the initial value if it's on the heap. Otherwise it's internal and we may not be able
+        // to allocate.
+        self->current_value_len = initial_value_bufinfo->len;
+        if (gc_alloc_possible()) {
+            if (gc_nbytes(initial_value_bufinfo->buf) > 0) {
+                uint8_t *initial_value = m_malloc(self->current_value_len);
+                self->current_value_alloc = self->current_value_len;
+                memcpy(initial_value, initial_value_bufinfo->buf, self->current_value_len);
+                self->current_value = initial_value;
+            } else {
+                self->current_value_alloc = 0;
+                self->current_value = initial_value_bufinfo->buf;
+            }
+        } else {
+            self->current_value = initial_value_bufinfo->buf;
+        }
+    }
 
     if (gc_alloc_possible()) {
         self->descriptor_list = mp_obj_new_list(0, NULL);

ports/espressif/common-hal/_bleio/Connection.c

@@ -63,7 +63,7 @@ int bleio_connection_event_cb(struct ble_gap_event *event, void *connection_in)
             connection->pair_status = PAIR_NOT_PAIRED;
 
             #if CIRCUITPY_VERBOSE_BLE
-            mp_printf(&mp_plat_print, "disconnected %02x\n", event->disconnect.reason);
+            mp_printf(&mp_plat_print, "event->disconnect.reason: 0x%x\n", event->disconnect.reason);
             #endif
             if (connection->connection_obj != mp_const_none) {
                 bleio_connection_obj_t *obj = connection->connection_obj;
@@ -209,6 +209,7 @@ STATIC int _discovered_characteristic_cb(uint16_t conn_handle,
             _last_discovery_status = error->status;
             xTaskNotifyGive(discovery_task);
         }
+        return 0;
     }
     // If any of these memory allocations fail, we set _last_discovery_status
     // and let the process continue.
@@ -233,11 +234,14 @@ STATIC int _discovered_characteristic_cb(uint16_t conn_handle,
         ((chr->properties & BLE_GATT_CHR_PROP_WRITE_NO_RSP) != 0 ? CHAR_PROP_WRITE_NO_RESPONSE : 0);
 
     // Call common_hal_bleio_characteristic_construct() to initialize some fields and set up evt handler.
+    mp_buffer_info_t mp_const_empty_bytes_bufinfo;
+    mp_get_buffer_raise(mp_const_empty_bytes, &mp_const_empty_bytes_bufinfo, MP_BUFFER_READ);
+
     common_hal_bleio_characteristic_construct(
         characteristic, service, chr->val_handle, uuid,
         props, SECURITY_MODE_OPEN, SECURITY_MODE_OPEN,
         0, false,   // max_length, fixed_length: values don't matter for gattc
-        mp_const_empty_bytes,
+        &mp_const_empty_bytes_bufinfo,
         NULL);
     // Set def_handle directly since it is only used in discovery.
     characteristic->def_handle = chr->def_handle;
@@ -260,6 +264,7 @@ STATIC int _discovered_descriptor_cb(uint16_t conn_handle,
             _last_discovery_status = error->status;
         }
         xTaskNotifyGive(discovery_task);
+        return 0;
     }
     // If any of these memory allocations fail, we set _last_discovery_status
     // and let the process continue.

ports/espressif/mpconfigport.h

@@ -28,6 +28,9 @@
 #ifndef MICROPY_INCLUDED_ESPRESSIF_MPCONFIGPORT_H
 #define MICROPY_INCLUDED_ESPRESSIF_MPCONFIGPORT_H
 
+// Enable for debugging.
+// #define CIRCUITPY_VERBOSE_BLE               (1)
+
 #define MICROPY_NLR_THUMB                   (0)
 
 #define MICROPY_USE_INTERNAL_PRINTF         (0)

py/circuitpy_mpconfig.h

@@ -470,7 +470,9 @@ void background_callback_run_all(void);
 #error "boot counter requires CIRCUITPY_NVM enabled"
 #endif
 
+#ifndef CIRCUITPY_VERBOSE_BLE
 #define CIRCUITPY_VERBOSE_BLE 0
+#endif
 
 // Display the Blinka logo in the REPL on displayio displays.
 #ifndef CIRCUITPY_REPL_LOGO