extmod/btstack: Implement gatts_db for btstack.

Work done in collaboration with Jim Mussared aka @jimmo.

1 files changed, 117 insertions, 31 deletions

diff --git a/extmod/btstack/modbluetooth_btstack.c b/extmod/btstack/modbluetooth_btstack.c
index e7f9014048..f285f3e45c 100644
--- a/extmod/btstack/modbluetooth_btstack.c
+++ b/extmod/btstack/modbluetooth_btstack.c
@@ -35,47 +35,69 @@
 
 #include "lib/btstack/src/btstack.h"
 
+#define DEBUG_EVENT_printf(...) //printf(__VA_ARGS__)
+
 volatile int mp_bluetooth_btstack_state = MP_BLUETOOTH_BTSTACK_STATE_OFF;
 
 static btstack_packet_callback_registration_t hci_event_callback_registration;
 
+STATIC int btstack_error_to_errno(int err) {
+    if (err == ERROR_CODE_SUCCESS) {
+        return 0;
+    } else if (err == BTSTACK_ACL_BUFFERS_FULL) {
+        return MP_ENOMEM;
+    } else {
+        return MP_EINVAL;
+    }
+}
+
 STATIC void att_server_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size) {
-    // printf("att_server_packet_handler: packet_type: %u, channel: %u, packet: %p, size: %u\n", packet_type, channel, packet, size);
+    DEBUG_EVENT_printf("att_server_packet_handler: packet_type: %u, channel: %u, packet: %p, size: %u\n", packet_type, channel, packet, size);
     if (packet_type == HCI_EVENT_PACKET) {
         uint8_t event_type = hci_event_packet_get_type(packet);
         if (event_type == ATT_EVENT_CONNECTED) {
-            printf("  --> att connected\n");
+            DEBUG_EVENT_printf("  --> att connected\n");
+            uint16_t conn_handle = att_event_connected_get_handle(packet);
+            uint8_t addr_type = att_event_connected_get_address_type(packet);
+            bd_addr_t addr;
+            att_event_connected_get_address(packet, addr);
+            mp_bluetooth_gap_on_connected_disconnected(MP_BLUETOOTH_IRQ_CENTRAL_CONNECT, conn_handle, addr_type, addr);
         } else if (event_type == ATT_EVENT_DISCONNECTED) {
-            printf("  --> att disconnected\n");
+            DEBUG_EVENT_printf("  --> att disconnected\n");
+            uint16_t conn_handle = att_event_disconnected_get_handle(packet);
+            bd_addr_t addr = {0};
+            mp_bluetooth_gap_on_connected_disconnected(MP_BLUETOOTH_IRQ_CENTRAL_DISCONNECT, conn_handle, 0, addr);
         } else if (event_type == HCI_EVENT_LE_META) {
-            printf("  --> att le meta\n");
+            DEBUG_EVENT_printf("  --> att le meta\n");
         } else if (event_type == HCI_EVENT_DISCONNECTION_COMPLETE) {
-            printf("  --> att disconnect complete\n");
+            DEBUG_EVENT_printf("  --> att disconnect complete\n");
         } else {
-            printf("  --> att type: unknown (%u)\n", event_type);
+            DEBUG_EVENT_printf("  --> att type: unknown (%u)\n", event_type);
         }
     }
 }
 
 STATIC void hci_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size) {
-    // printf("hci_packet_handler: packet_type: %u, channel: %u, packet: %p, size: %u\n", packet_type, channel, packet, size);
+    DEBUG_EVENT_printf("hci_packet_handler: packet_type: %u, channel: %u, packet: %p, size: %u\n", packet_type, channel, packet, size);
     if (packet_type == HCI_EVENT_PACKET) {
         uint8_t event_type = hci_event_packet_get_type(packet);
         if (event_type == HCI_EVENT_TRANSPORT_PACKET_SENT || event_type == HCI_EVENT_COMMAND_COMPLETE) {
         } else if (event_type == BTSTACK_EVENT_NR_CONNECTIONS_CHANGED) {
-            printf("  --> hci type: # conns changed\n");
+            DEBUG_EVENT_printf("  --> hci type: # conns changed\n");
         } else if (event_type == HCI_EVENT_VENDOR_SPECIFIC) {
-            printf("  --> hci type: vendor specific\n");
+            DEBUG_EVENT_printf("  --> hci type: vendor specific\n");
         } else {
-            printf("  --> hci type: unknown (%u)\n", event_type);
+            DEBUG_EVENT_printf("  --> hci type: unknown (%u)\n", event_type);
         }
     }
 }
 
 int mp_bluetooth_init(void) {
+    DEBUG_EVENT_printf("mp_bluetooth_init\n");
     btstack_memory_init();
 
     MP_STATE_PORT(bluetooth_btstack_root_pointers) = m_new0(mp_bluetooth_btstack_root_pointers_t, 1);
+    mp_bluetooth_gatts_db_create(&MP_STATE_PORT(bluetooth_btstack_root_pointers)->gatts_db);
 
     mp_bluetooth_btstack_port_init();
     mp_bluetooth_btstack_state = MP_BLUETOOTH_BTSTACK_STATE_STARTING;
@@ -106,6 +128,7 @@ int mp_bluetooth_init(void) {
 }
 
 void mp_bluetooth_deinit(void) {
+    DEBUG_EVENT_printf("mp_bluetooth_deinit\n");
     mp_bluetooth_btstack_port_deinit();
     mp_bluetooth_btstack_state = MP_BLUETOOTH_BTSTACK_STATE_OFF;
 
@@ -121,6 +144,7 @@ void mp_bluetooth_get_device_addr(uint8_t *addr) {
 }
 
 int mp_bluetooth_gap_advertise_start(bool connectable, int32_t interval_us, const uint8_t *adv_data, size_t adv_data_len, const uint8_t *sr_data, size_t sr_data_len) {
+    DEBUG_EVENT_printf("mp_bluetooth_gap_advertise_start\n");
     uint16_t adv_int_min = interval_us / 625;
     uint16_t adv_int_max = interval_us / 625;
     uint8_t adv_type = connectable ? 0 : 2;
@@ -156,12 +180,14 @@ int mp_bluetooth_gap_advertise_start(bool connectable, int32_t interval_us, cons
 }
 
 void mp_bluetooth_gap_advertise_stop(void) {
+    DEBUG_EVENT_printf("mp_bluetooth_gap_advertise_stop\n");
     gap_advertisements_enable(false);
     MP_STATE_PORT(bluetooth_btstack_root_pointers)->adv_data_alloc = 0;
     MP_STATE_PORT(bluetooth_btstack_root_pointers)->adv_data = NULL;
 }
 
 int mp_bluetooth_gatts_register_service_begin(bool append) {
+    DEBUG_EVENT_printf("mp_bluetooth_gatts_register_service_begin\n");
     if (!append) {
         // This will reset the DB.
         // Becase the DB is statically allocated, there's no problem with just re-initing it.
@@ -173,43 +199,68 @@ int mp_bluetooth_gatts_register_service_begin(bool append) {
 
         att_db_util_add_service_uuid16(0x1801);
         att_db_util_add_characteristic_uuid16(0x2a05, ATT_PROPERTY_READ, ATT_SECURITY_NONE, ATT_SECURITY_NONE, NULL, 0);
-
     }
 
     return 0;
 }
 
 STATIC uint16_t att_read_callback(hci_con_handle_t connection_handle, uint16_t att_handle, uint16_t offset, uint8_t *buffer, uint16_t buffer_size) {
-    printf("btstack: att_read_callback (handle: %u, offset: %u, buffer: %p, size: %u)\n", att_handle, offset, buffer, buffer_size);
-    return 0;
+    DEBUG_EVENT_printf("btstack: att_read_callback (handle: %u, offset: %u, buffer: %p, size: %u)\n", att_handle, offset, buffer, buffer_size);
+    mp_bluetooth_gatts_db_entry_t *entry = mp_bluetooth_gatts_db_lookup(MP_STATE_PORT(bluetooth_btstack_root_pointers)->gatts_db, att_handle);
+    if (!entry) {
+        DEBUG_EVENT_printf("btstack: att_read_callback handle not found\n");
+        return 0; // TODO: Find status code for not-found.
+    }
+
+    return att_read_callback_handle_blob(entry->data, entry->data_len, offset, buffer, buffer_size);
 }
 
 STATIC int att_write_callback(hci_con_handle_t connection_handle, uint16_t att_handle, uint16_t transaction_mode, uint16_t offset, uint8_t *buffer, uint16_t buffer_size) {
-    printf("btstack: att_write_callback (handle: %u, mode: %u, offset: %u, buffer: %p, size: %u)\n", att_handle, transaction_mode, offset, buffer, buffer_size);
+    DEBUG_EVENT_printf("btstack: att_write_callback (handle: %u, mode: %u, offset: %u, buffer: %p, size: %u)\n", att_handle, transaction_mode, offset, buffer, buffer_size);
+    mp_bluetooth_gatts_db_entry_t *entry = mp_bluetooth_gatts_db_lookup(MP_STATE_PORT(bluetooth_btstack_root_pointers)->gatts_db, att_handle);
+    if (!entry) {
+        DEBUG_EVENT_printf("btstack: att_write_callback handle not found\n");
+        return 0; // TODO: Find status code for not-found.
+    }
+
+    // TODO: Use `offset` arg.
+    size_t append_offset = 0;
+    if (entry->append) {
+        append_offset = entry->data_len;
+    }
+    entry->data_len = MIN(entry->data_alloc, buffer_size + append_offset);
+    memcpy(entry->data + append_offset, buffer, entry->data_len - append_offset);
+
+    mp_bluetooth_gatts_on_write(connection_handle, att_handle);
+
     return 0;
 }
 
-// Note: modbluetooth UUIDs store their data in LE.
 STATIC inline uint16_t get_uuid16(const mp_obj_bluetooth_uuid_t *uuid) {
     return (uuid->data[1] << 8) | uuid->data[0];
 }
 
 int mp_bluetooth_gatts_register_service(mp_obj_bluetooth_uuid_t *service_uuid, mp_obj_bluetooth_uuid_t **characteristic_uuids, uint8_t *characteristic_flags, mp_obj_bluetooth_uuid_t **descriptor_uuids, uint8_t *descriptor_flags, uint8_t *num_descriptors, uint16_t *handles, size_t num_characteristics) {
-    // TODO: It's not clear which endian btstack needs for uuids.
+    DEBUG_EVENT_printf("mp_bluetooth_gatts_register_service\n");
+    // Note: btstack expects BE UUIDs (which it immediately convertes to LE).
+    // So we have to convert all our modbluetooth LE UUIDs to BE just for the att_db_util_add_* methods (using get_uuid16 above, and reverse_128 from btstackutil.h).
+
+    // TODO: btstack's att_db_util_add_* methods have no bounds checking or validation.
+    // Need some way to prevent additional services being added if we're out of space in the static buffer.
 
-    uint16_t service_handle;
     if (service_uuid->type == MP_BLUETOOTH_UUID_TYPE_16) {
-        service_handle = att_db_util_add_service_uuid16(get_uuid16(service_uuid));
+        att_db_util_add_service_uuid16(get_uuid16(service_uuid));
     } else if (service_uuid->type == MP_BLUETOOTH_UUID_TYPE_128) {
-        service_handle = att_db_util_add_service_uuid128(service_uuid->data);
+        uint8_t buffer[16];
+        reverse_128(service_uuid->data, buffer);
+        att_db_util_add_service_uuid128(buffer);
     } else {
         return MP_EINVAL;
     }
 
-    printf("Registered service with handle %u\n", service_handle);
-
     size_t handle_index = 0;
     size_t descriptor_index = 0;
+    static uint8_t cccb_buf[2] = {0};
 
     for (size_t i = 0; i < num_characteristics; ++i) {
         uint16_t props = characteristic_flags[i] | ATT_PROPERTY_DYNAMIC;
@@ -218,11 +269,20 @@ int mp_bluetooth_gatts_register_service(mp_obj_bluetooth_uuid_t *service_uuid, m
         if (characteristic_uuids[i]->type == MP_BLUETOOTH_UUID_TYPE_16) {
             handles[handle_index] = att_db_util_add_characteristic_uuid16(get_uuid16(characteristic_uuids[i]), props, read_permission, write_permission, NULL, 0);
         } else if (characteristic_uuids[i]->type == MP_BLUETOOTH_UUID_TYPE_128) {
-            handles[handle_index] = att_db_util_add_characteristic_uuid128(characteristic_uuids[i]->data, props, read_permission, write_permission, NULL, 0);
+            uint8_t buffer[16];
+            reverse_128(characteristic_uuids[i]->data, buffer);
+            handles[handle_index] = att_db_util_add_characteristic_uuid128(buffer, props, read_permission, write_permission, NULL, 0);
         } else {
             return MP_EINVAL;
         }
-        printf("Registered char with handle %u\n", handles[handle_index]);
+        mp_bluetooth_gatts_db_create_entry(MP_STATE_PORT(bluetooth_btstack_root_pointers)->gatts_db, handles[handle_index], MP_BLUETOOTH_DEFAULT_ATTR_LEN);
+        // If a NOTIFY or INDICATE characteristic is added, then we need to manage a value for the CCCB.
+        if (props & (ATT_PROPERTY_NOTIFY | ATT_PROPERTY_INDICATE)) {
+            // btstack creates the CCCB as the next handle.
+            mp_bluetooth_gatts_db_create_entry(MP_STATE_PORT(bluetooth_btstack_root_pointers)->gatts_db, handles[handle_index] + 1, MP_BLUETOOTH_CCCB_LEN);
+            mp_bluetooth_gatts_db_write(MP_STATE_PORT(bluetooth_btstack_root_pointers)->gatts_db, handles[handle_index] + 1, cccb_buf, sizeof(cccb_buf));
+        }
+        DEBUG_EVENT_printf("Registered char with handle %u\n", handles[handle_index]);
         ++handle_index;
 
         for (size_t j = 0; j < num_descriptors[i]; ++j) {
@@ -233,11 +293,14 @@ int mp_bluetooth_gatts_register_service(mp_obj_bluetooth_uuid_t *service_uuid, m
             if (descriptor_uuids[descriptor_index]->type == MP_BLUETOOTH_UUID_TYPE_16) {
                 handles[handle_index] = att_db_util_add_descriptor_uuid16(get_uuid16(descriptor_uuids[descriptor_index]), props, read_permission, write_permission, NULL, 0);
             } else if (descriptor_uuids[descriptor_index]->type == MP_BLUETOOTH_UUID_TYPE_128) {
-                handles[handle_index] = att_db_util_add_descriptor_uuid128(descriptor_uuids[descriptor_index]->data, props, read_permission, write_permission, NULL, 0);
+                uint8_t buffer[16];
+                reverse_128(descriptor_uuids[descriptor_index]->data, buffer);
+                handles[handle_index] = att_db_util_add_descriptor_uuid128(buffer, props, read_permission, write_permission, NULL, 0);
             } else {
                 return MP_EINVAL;
             }
-            printf("Registered desc with handle %u\n", handles[handle_index]);
+            mp_bluetooth_gatts_db_create_entry(MP_STATE_PORT(bluetooth_btstack_root_pointers)->gatts_db, handles[handle_index], MP_BLUETOOTH_DEFAULT_ATTR_LEN);
+            DEBUG_EVENT_printf("Registered desc with handle %u\n", handles[handle_index]);
             ++descriptor_index;
             ++handle_index;
         }
@@ -247,68 +310,91 @@ int mp_bluetooth_gatts_register_service(mp_obj_bluetooth_uuid_t *service_uuid, m
 }
 
 int mp_bluetooth_gatts_register_service_end(void) {
+    DEBUG_EVENT_printf("mp_bluetooth_gatts_register_service_end\n");
     att_server_init(att_db_util_get_address(), &att_read_callback, &att_write_callback);
     return 0;
 }
 
 int mp_bluetooth_gatts_read(uint16_t value_handle, uint8_t **value, size_t *value_len) {
-    return 0;
+    DEBUG_EVENT_printf("mp_bluetooth_gatts_read\n");
+    return mp_bluetooth_gatts_db_read(MP_STATE_PORT(bluetooth_btstack_root_pointers)->gatts_db, value_handle, value, value_len);
 }
 
 int mp_bluetooth_gatts_write(uint16_t value_handle, const uint8_t *value, size_t value_len) {
-    return 0;
+    DEBUG_EVENT_printf("mp_bluetooth_gatts_write\n");
+    return mp_bluetooth_gatts_db_write(MP_STATE_PORT(bluetooth_btstack_root_pointers)->gatts_db, value_handle, value, value_len);
 }
 
 int mp_bluetooth_gatts_notify(uint16_t conn_handle, uint16_t value_handle) {
-    return 0;
+    DEBUG_EVENT_printf("mp_bluetooth_gatts_notify\n");
+    // Note: btstack doesn't appear to support sending a notification without a value, so include the stored value.
+    uint8_t *data = NULL;
+    size_t len = 0;
+    mp_bluetooth_gatts_db_read(MP_STATE_PORT(bluetooth_btstack_root_pointers)->gatts_db, value_handle, &data, &len);
+    return mp_bluetooth_gatts_notify_send(conn_handle, value_handle, data, &len);
 }
 
 int mp_bluetooth_gatts_notify_send(uint16_t conn_handle, uint16_t value_handle, const uint8_t *value, size_t *value_len) {
-    return 0;
+    DEBUG_EVENT_printf("mp_bluetooth_gatts_notify_send\n");
+    // TODO: We need to use att_server_request_to_send_notification here as the stack may not be ready to send a notification.
+    int err = att_server_notify(conn_handle, value_handle, value, *value_len);
+    return btstack_error_to_errno(err);
 }
 
 int mp_bluetooth_gatts_indicate(uint16_t conn_handle, uint16_t value_handle) {
-    return 0;
+    DEBUG_EVENT_printf("mp_bluetooth_gatts_indicate\n");
+    return btstack_error_to_errno(att_server_indicate(conn_handle, value_handle, NULL, 0));
 }
 
 int mp_bluetooth_gatts_set_buffer(uint16_t value_handle, size_t len, bool append) {
-    return 0;
+    DEBUG_EVENT_printf("mp_bluetooth_gatts_set_buffer\n");
+    return mp_bluetooth_gatts_db_resize(MP_STATE_PORT(bluetooth_btstack_root_pointers)->gatts_db, value_handle, len, append);
 }
 
 int mp_bluetooth_gap_disconnect(uint16_t conn_handle) {
+    DEBUG_EVENT_printf("mp_bluetooth_gap_disconnect\n");
+    gap_disconnect(conn_handle);
     return 0;
 }
 
 #if MICROPY_PY_BLUETOOTH_ENABLE_CENTRAL_MODE
 int mp_bluetooth_gap_scan_start(int32_t duration_ms, int32_t interval_us, int32_t window_us) {
+    DEBUG_EVENT_printf("mp_bluetooth_gap_scan_start\n");
     return 0;
 }
 
 int mp_bluetooth_gap_scan_stop(void) {
+    DEBUG_EVENT_printf("mp_bluetooth_gap_scan_stop\n");
     return 0;
 }
 
 int mp_bluetooth_gap_peripheral_connect(uint8_t addr_type, const uint8_t *addr, int32_t duration_ms) {
+    DEBUG_EVENT_printf("mp_bluetooth_gap_peripheral_connect\n");
     return 0;
 }
 
 int mp_bluetooth_gattc_discover_primary_services(uint16_t conn_handle) {
+    DEBUG_EVENT_printf("mp_bluetooth_gattc_discover_primary_services\n");
     return 0;
 }
 
 int mp_bluetooth_gattc_discover_characteristics(uint16_t conn_handle, uint16_t start_handle, uint16_t end_handle) {
+    DEBUG_EVENT_printf("mp_bluetooth_gattc_discover_characteristics\n");
     return 0;
 }
 
 int mp_bluetooth_gattc_discover_descriptors(uint16_t conn_handle, uint16_t start_handle, uint16_t end_handle) {
+    DEBUG_EVENT_printf("mp_bluetooth_gattc_discover_descriptors\n");
     return 0;
 }
 
 int mp_bluetooth_gattc_read(uint16_t conn_handle, uint16_t value_handle) {
+    DEBUG_EVENT_printf("mp_bluetooth_gattc_read\n");
     return 0;
 }
 
 int mp_bluetooth_gattc_write(uint16_t conn_handle, uint16_t value_handle, const uint8_t *value, size_t *value_len, unsigned int mode) {
+    DEBUG_EVENT_printf("mp_bluetooth_gattc_write\n");
     return 0;
 }
 #endif