1 files changed, 211 insertions, 0 deletions
diff --git a/circuitpython/supervisor/shared/bluetooth/serial.c b/circuitpython/supervisor/shared/bluetooth/serial.c
new file mode 100644
index 0000000..2edf3c7
--- /dev/null
+++ b/circuitpython/supervisor/shared/bluetooth/serial.c
@@ -0,0 +1,211 @@
+/*
+ * This file is part of the MicroPython project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2021 Scott Shawcroft for Adafruit Industries
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include <string.h>
+
+#include "genhdr/mpversion.h"
+#include "shared-bindings/_bleio/__init__.h"
+#include "shared-bindings/_bleio/Adapter.h"
+#include "shared-bindings/_bleio/Characteristic.h"
+#include "shared-bindings/_bleio/CharacteristicBuffer.h"
+#include "shared-bindings/_bleio/PacketBuffer.h"
+#include "shared-bindings/_bleio/Service.h"
+#include "shared-bindings/_bleio/UUID.h"
+#include "shared-module/storage/__init__.h"
+#include "supervisor/shared/bluetooth/serial.h"
+
+#include "common-hal/_bleio/__init__.h"
+
+#include "py/mpstate.h"
+
+STATIC bleio_service_obj_t supervisor_ble_circuitpython_service;
+STATIC bleio_uuid_obj_t supervisor_ble_circuitpython_service_uuid;
+STATIC bleio_characteristic_obj_t supervisor_ble_circuitpython_rx_characteristic;
+STATIC bleio_uuid_obj_t supervisor_ble_circuitpython_rx_uuid;
+STATIC bleio_characteristic_obj_t supervisor_ble_circuitpython_tx_characteristic;
+STATIC bleio_uuid_obj_t supervisor_ble_circuitpython_tx_uuid;
+STATIC bleio_characteristic_obj_t supervisor_ble_circuitpython_version_characteristic;
+STATIC bleio_uuid_obj_t supervisor_ble_circuitpython_version_uuid;
+
+// This is the base UUID for the CircuitPython service.
+const uint8_t circuitpython_base_uuid[16] = {0x6e, 0x68, 0x74, 0x79, 0x50, 0x74, 0x69, 0x75, 0x63, 0x72, 0x69, 0x43, 0x00, 0x00, 0xaf, 0xad };
+
+STATIC mp_obj_list_t characteristic_list;
+STATIC mp_obj_t characteristic_list_items[3];
+
+STATIC uint32_t _outgoing1[BLE_GATTS_VAR_ATTR_LEN_MAX / 4];
+STATIC uint32_t _outgoing2[BLE_GATTS_VAR_ATTR_LEN_MAX / 4];
+STATIC ble_drv_evt_handler_entry_t rx_static_handler_entry;
+STATIC ble_drv_evt_handler_entry_t tx_static_handler_entry;
+STATIC bleio_packet_buffer_obj_t _tx_packet_buffer;
+STATIC uint32_t _incoming[64];
+STATIC bleio_characteristic_buffer_obj_t _rx_buffer;
+
+// Internal enabling so we can disable while printing BLE debugging.
+STATIC bool _enabled;
+
+void supervisor_start_bluetooth_serial(void) {
+    supervisor_ble_circuitpython_service_uuid.base.type = &bleio_uuid_type;
+    common_hal_bleio_uuid_construct(&supervisor_ble_circuitpython_service_uuid, 0x0001, circuitpython_base_uuid);
+
+    // We know we'll only be N characteristics so we can statically allocate it.
+    characteristic_list.base.type = &mp_type_list;
+    characteristic_list.alloc = sizeof(characteristic_list_items) / sizeof(characteristic_list_items[0]);
+    characteristic_list.len = 0;
+    characteristic_list.items = characteristic_list_items;
+    mp_seq_clear(characteristic_list.items, 0, characteristic_list.alloc, sizeof(*characteristic_list.items));
+
+    supervisor_ble_circuitpython_service.base.type = &bleio_service_type;
+    _common_hal_bleio_service_construct(&supervisor_ble_circuitpython_service, &supervisor_ble_circuitpython_service_uuid, false /* is secondary */, &characteristic_list);
+
+    // RX
+    supervisor_ble_circuitpython_rx_uuid.base.type = &bleio_uuid_type;
+    common_hal_bleio_uuid_construct(&supervisor_ble_circuitpython_rx_uuid, 0x0002, circuitpython_base_uuid);
+    common_hal_bleio_characteristic_construct(&supervisor_ble_circuitpython_rx_characteristic,
+        &supervisor_ble_circuitpython_service,
+        0,                                       // handle (for remote only)
+        &supervisor_ble_circuitpython_rx_uuid,
+        CHAR_PROP_WRITE | CHAR_PROP_WRITE_NO_RESPONSE,
+        SECURITY_MODE_NO_ACCESS,
+        SECURITY_MODE_ENC_NO_MITM,
+        BLE_GATTS_VAR_ATTR_LEN_MAX,                 // max length
+        false,                                      // fixed length
+        NULL,                                      // no initial value
+        NULL);
+
+    // TX
+    supervisor_ble_circuitpython_tx_uuid.base.type = &bleio_uuid_type;
+    common_hal_bleio_uuid_construct(&supervisor_ble_circuitpython_tx_uuid, 0x0003, circuitpython_base_uuid);
+    common_hal_bleio_characteristic_construct(&supervisor_ble_circuitpython_tx_characteristic,
+        &supervisor_ble_circuitpython_service,
+        0,                                       // handle (for remote only)
+        &supervisor_ble_circuitpython_tx_uuid,
+        CHAR_PROP_NOTIFY,
+        SECURITY_MODE_ENC_NO_MITM,
+        SECURITY_MODE_NO_ACCESS,
+        BLE_GATTS_VAR_ATTR_LEN_MAX,                  // max length
+        false,                                       // fixed length
+        NULL,                                       // no initial value
+        NULL);
+
+    // Version number
+    const char *version = MICROPY_GIT_TAG;
+    mp_buffer_info_t bufinfo;
+    bufinfo.buf = (uint8_t *)version;
+    bufinfo.len = strlen(version);
+
+    supervisor_ble_circuitpython_version_uuid.base.type = &bleio_uuid_type;
+    common_hal_bleio_uuid_construct(&supervisor_ble_circuitpython_version_uuid, 0x0100, circuitpython_base_uuid);
+    common_hal_bleio_characteristic_construct(&supervisor_ble_circuitpython_version_characteristic,
+        &supervisor_ble_circuitpython_service,
+        0,                                       // handle (for remote only)
+        &supervisor_ble_circuitpython_version_uuid,
+        CHAR_PROP_READ,
+        SECURITY_MODE_OPEN,
+        SECURITY_MODE_NO_ACCESS,
+        bufinfo.len,                                // max length
+        true,                                       // fixed length
+        NULL,                                       // no initial value
+        NULL); // no description
+
+    common_hal_bleio_characteristic_set_value(&supervisor_ble_circuitpython_version_characteristic, &bufinfo);
+
+    // Use a PacketBuffer to transmit so that we glom characters to transmit
+    // together and save BLE overhead.
+    _common_hal_bleio_packet_buffer_construct(
+        &_tx_packet_buffer, &supervisor_ble_circuitpython_tx_characteristic,
+        NULL, 0,
+        _outgoing1, _outgoing2, BLE_GATTS_VAR_ATTR_LEN_MAX,
+        &tx_static_handler_entry);
+
+    // Use a CharacteristicBuffer for rx so we can read a single character at a time.
+    _common_hal_bleio_characteristic_buffer_construct(&_rx_buffer,
+        &supervisor_ble_circuitpython_rx_characteristic,
+        0.1f,
+        (uint8_t *)_incoming, sizeof(_incoming) * sizeof(uint32_t),
+        &rx_static_handler_entry);
+
+    _enabled = true;
+}
+
+void supervisor_stop_bluetooth_serial(void) {
+    if (common_hal_bleio_packet_buffer_deinited(&_tx_packet_buffer)) {
+        return;
+    }
+    if (!_enabled) {
+        return;
+    }
+    common_hal_bleio_packet_buffer_flush(&_tx_packet_buffer);
+}
+
+bool ble_serial_connected(void) {
+    return _tx_packet_buffer.conn_handle != BLE_CONN_HANDLE_INVALID;
+}
+
+bool ble_serial_available(void) {
+    return _enabled &&
+           !common_hal_bleio_characteristic_buffer_deinited(&_rx_buffer) &&
+           common_hal_bleio_characteristic_buffer_rx_characters_available(&_rx_buffer);
+}
+
+char ble_serial_read_char(void) {
+    if (common_hal_bleio_characteristic_buffer_deinited(&_rx_buffer)) {
+        return -1;
+    }
+    if (!_enabled) {
+        return -1;
+    }
+    uint8_t c;
+    common_hal_bleio_characteristic_buffer_read(&_rx_buffer, &c, 1, NULL);
+    return c;
+}
+
+void ble_serial_write(const char *text, size_t len) {
+    if (common_hal_bleio_packet_buffer_deinited(&_tx_packet_buffer)) {
+        return;
+    }
+    if (!_enabled) {
+        return;
+    }
+    size_t sent = 0;
+    while (sent < len) {
+        uint16_t packet_size = MIN(len - sent, (size_t)common_hal_bleio_packet_buffer_get_outgoing_packet_length(&_tx_packet_buffer));
+        mp_int_t written = common_hal_bleio_packet_buffer_write(&_tx_packet_buffer, (const uint8_t *)text + sent, packet_size, NULL, 0);
+        // Error, so we drop characters to transmit.
+        if (written < 0) {
+            break;
+        }
+        sent += written;
+    }
+}
+
+void ble_serial_enable(void) {
+    _enabled = true;
+}
+
+void ble_serial_disable(void) {
+    _enabled = false;
+}