diff options
Diffstat (limited to 'app/src/split/bluetooth/central.c')
| -rw-r--r-- | app/src/split/bluetooth/central.c | 301 |
1 files changed, 301 insertions, 0 deletions
diff --git a/app/src/split/bluetooth/central.c b/app/src/split/bluetooth/central.c new file mode 100644 index 0000000..b6d7222 --- /dev/null +++ b/app/src/split/bluetooth/central.c @@ -0,0 +1,301 @@ +/* + * Copyright (c) 2020 Peter Johanson + * + * SPDX-License-Identifier: MIT + */ + +#include <zephyr/types.h> + +#include <bluetooth/bluetooth.h> +#include <bluetooth/conn.h> +#include <bluetooth/uuid.h> +#include <bluetooth/gatt.h> +#include <sys/byteorder.h> + +#include <logging/log.h> + +LOG_MODULE_DECLARE(zmk, CONFIG_ZMK_LOG_LEVEL); + +#include <zmk/split/bluetooth/uuid.h> +#include <zmk/event-manager.h> +#include <zmk/events/position-state-changed.h> +#include <init.h> + +static int start_scan(void); + +#define POSITION_STATE_DATA_LEN 16 + +static struct bt_conn *default_conn; + +static struct bt_uuid_128 uuid = BT_UUID_INIT_128(ZMK_SPLIT_BT_SERVICE_UUID); +static struct bt_gatt_discover_params discover_params; +static struct bt_gatt_subscribe_params subscribe_params; + +static u8_t split_central_notify_func(struct bt_conn *conn, + struct bt_gatt_subscribe_params *params, + const void *data, u16_t length) +{ + static u8_t position_state[POSITION_STATE_DATA_LEN]; + + u8_t changed_positions[POSITION_STATE_DATA_LEN]; + + if (!data) { + LOG_DBG("[UNSUBSCRIBED]"); + params->value_handle = 0U; + return BT_GATT_ITER_STOP; + } + + LOG_DBG("[NOTIFICATION] data %p length %u", data, length); + + for (int i = 0; i < POSITION_STATE_DATA_LEN; i++) { + changed_positions[i] = ((u8_t *)data)[i] ^ position_state[i]; + position_state[i] = ((u8_t *)data)[i]; + } + + for (int i = 0; i < POSITION_STATE_DATA_LEN; i++) { + for (int j = 0; j < 8; j++) { + if (changed_positions[i] & BIT(j)) { + u32_t position = (i * 8) + j; + bool pressed = position_state[i] & BIT(j); + struct position_state_changed *pos_ev = new_position_state_changed(); + pos_ev->position = position; + pos_ev->state = pressed; + + LOG_DBG("Trigger key position state change for %d", position); + ZMK_EVENT_RAISE(pos_ev); + } + } + } + + + return BT_GATT_ITER_CONTINUE; +} + +static u8_t split_central_discovery_func(struct bt_conn *conn, + const struct bt_gatt_attr *attr, + struct bt_gatt_discover_params *params) +{ + int err; + + if (!attr) { + LOG_DBG("Discover complete"); + (void)memset(params, 0, sizeof(*params)); + return BT_GATT_ITER_STOP; + } + + LOG_DBG("[ATTRIBUTE] handle %u", attr->handle); + + if (!bt_uuid_cmp(discover_params.uuid, BT_UUID_DECLARE_128(ZMK_SPLIT_BT_SERVICE_UUID))) { + memcpy(&uuid, BT_UUID_DECLARE_128(ZMK_SPLIT_BT_CHAR_POSITION_STATE_UUID), sizeof(uuid)); + discover_params.uuid = &uuid.uuid; + discover_params.start_handle = attr->handle + 1; + discover_params.type = BT_GATT_DISCOVER_CHARACTERISTIC; + + err = bt_gatt_discover(conn, &discover_params); + if (err) { + LOG_ERR("Discover failed (err %d)", err); + } + } else if (!bt_uuid_cmp(discover_params.uuid, + BT_UUID_DECLARE_128(ZMK_SPLIT_BT_CHAR_POSITION_STATE_UUID))) { + memcpy(&uuid, BT_UUID_GATT_CCC, sizeof(uuid)); + discover_params.uuid = &uuid.uuid; + discover_params.start_handle = attr->handle + 2; + discover_params.type = BT_GATT_DISCOVER_DESCRIPTOR; + subscribe_params.value_handle = bt_gatt_attr_value_handle(attr); + + err = bt_gatt_discover(conn, &discover_params); + if (err) { + LOG_ERR("Discover failed (err %d)", err); + } + } else { + subscribe_params.notify = split_central_notify_func; + subscribe_params.value = BT_GATT_CCC_NOTIFY; + subscribe_params.ccc_handle = attr->handle; + + err = bt_gatt_subscribe(conn, &subscribe_params); + if (err && err != -EALREADY) { + LOG_ERR("Subscribe failed (err %d)", err); + } else { + LOG_DBG("[SUBSCRIBED]"); + } + + return BT_GATT_ITER_STOP; + } + + return BT_GATT_ITER_STOP; +} + +static void split_central_process_connection(struct bt_conn *conn) { + int err; + + LOG_DBG("Current security for connection: %d", bt_conn_get_security(conn)); + + err = bt_conn_set_security(conn, BT_SECURITY_L2); + if (err) { + LOG_ERR("Failed to set security (reason %d)", err); + return; + } + + if (conn == default_conn) { + discover_params.uuid = &uuid.uuid; + discover_params.func = split_central_discovery_func; + discover_params.start_handle = 0x0001; + discover_params.end_handle = 0xffff; + discover_params.type = BT_GATT_DISCOVER_PRIMARY; + + err = bt_gatt_discover(default_conn, &discover_params); + if (err) { + LOG_ERR("Discover failed(err %d)", err); + return; + } + } +} + +static bool split_central_eir_found(struct bt_data *data, void *user_data) +{ + bt_addr_le_t *addr = user_data; + int i; + + LOG_DBG("[AD]: %u data_len %u", data->type, data->data_len); + + switch (data->type) { + case BT_DATA_UUID128_SOME: + case BT_DATA_UUID128_ALL: + if (data->data_len % 16 != 0U) { + LOG_ERR("AD malformed"); + return true; + } + + for (i = 0; i < data->data_len; i += 16) { + struct bt_le_conn_param *param; + struct bt_uuid uuid; + int err; + + if (!bt_uuid_create(&uuid, &data->data[i], 16)) { + LOG_ERR("Unable to load UUID"); + continue; + } + + if (!bt_uuid_cmp(&uuid, BT_UUID_DECLARE_128(ZMK_SPLIT_BT_SERVICE_UUID))) { + char uuid_str[BT_UUID_STR_LEN]; + char service_uuid_str[BT_UUID_STR_LEN]; + + bt_uuid_to_str(&uuid, uuid_str, sizeof(uuid_str)); + bt_uuid_to_str(BT_UUID_DECLARE_128(ZMK_SPLIT_BT_SERVICE_UUID), service_uuid_str, sizeof(service_uuid_str)); + LOG_DBG("UUID %s does not match split UUID: %s", log_strdup(uuid_str), log_strdup(service_uuid_str)); + continue; + } + + LOG_DBG("Found the split service"); + + err = bt_le_scan_stop(); + if (err) { + LOG_ERR("Stop LE scan failed (err %d)", err); + continue; + } + + default_conn = bt_conn_lookup_addr_le(BT_ID_DEFAULT, addr); + if (default_conn) { + LOG_DBG("Found existing connection"); + split_central_process_connection(default_conn); + } else { + param = BT_LE_CONN_PARAM(0x0006, 0x000c, 5, 400); + err = bt_conn_le_create(addr, BT_CONN_LE_CREATE_CONN, + param, &default_conn); + if (err) { + LOG_ERR("Create conn failed (err %d)", err); + start_scan(); + } + } + + return false; + } + } + + return true; +} + +static void split_central_device_found(const bt_addr_le_t *addr, s8_t rssi, u8_t type, + struct net_buf_simple *ad) +{ + char dev[BT_ADDR_LE_STR_LEN]; + + bt_addr_le_to_str(addr, dev, sizeof(dev)); + LOG_DBG("[DEVICE]: %s, AD evt type %u, AD data len %u, RSSI %i", + log_strdup(dev), type, ad->len, rssi); + + /* We're only interested in connectable events */ + if (type == BT_GAP_ADV_TYPE_ADV_IND || + type == BT_GAP_ADV_TYPE_ADV_DIRECT_IND) { + bt_data_parse(ad, split_central_eir_found, (void *)addr); + } +} + +static int start_scan(void) +{ + int err; + + err = bt_le_scan_start(BT_LE_SCAN_PASSIVE, split_central_device_found); + if (err) { + LOG_ERR("Scanning failed to start (err %d)", err); + return err; + } + + LOG_DBG("Scanning successfully started"); + return 0; +} + +static void split_central_connected(struct bt_conn *conn, u8_t conn_err) +{ + char addr[BT_ADDR_LE_STR_LEN]; + + bt_addr_le_to_str(bt_conn_get_dst(conn), addr, sizeof(addr)); + + if (conn_err) { + LOG_ERR("Failed to connect to %s (%u)", addr, conn_err); + + bt_conn_unref(default_conn); + default_conn = NULL; + + start_scan(); + return; + } + + LOG_DBG("Connected: %s", log_strdup(addr)); + + split_central_process_connection(conn); +} + +static void split_central_disconnected(struct bt_conn *conn, u8_t reason) +{ + char addr[BT_ADDR_LE_STR_LEN]; + + bt_addr_le_to_str(bt_conn_get_dst(conn), addr, sizeof(addr)); + + LOG_DBG("Disconnected: %s (reason %d)", log_strdup(addr), reason); + + if (default_conn != conn) { + return; + } + + bt_conn_unref(default_conn); + default_conn = NULL; + + start_scan(); +} + +static struct bt_conn_cb conn_callbacks = { + .connected = split_central_connected, + .disconnected = split_central_disconnected, +}; + +int zmk_split_bt_central_init(struct device *_arg) +{ + bt_conn_cb_register(&conn_callbacks); + + return start_scan(); +} + +SYS_INIT(zmk_split_bt_central_init, + APPLICATION, + CONFIG_ZMK_BLE_INIT_PRIORITY);
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