applications: nrf_desktop: Separate discovery and handling subscribers

Separate functions related to handling subscribers and discovery to
simplify code.

Jira: NCSDK-20843

Signed-off-by: Marek Pieta <Marek.Pieta@nordicsemi.no>

applications/nrf_desktop/src/modules/ble_scan.c

@@ -8,6 +8,7 @@
 
 #include <zephyr/bluetooth/bluetooth.h>
 #include <bluetooth/scan.h>
+#include <bluetooth/gatt_dm.h>
 #include <zephyr/settings/settings.h>
 
 #include <string.h>
@@ -52,6 +53,79 @@ static bool scanning;
 static bool scan_blocked;
 static bool ble_bond_ready;
 
+static void store_subscribed_peers(void)
+{
+ if (IS_ENABLED(CONFIG_SETTINGS)) {
+ char key[] = MODULE_NAME "/" SUBSCRIBED_PEERS_STORAGE_NAME;
+ int err = settings_save_one(key, subscribed_peers, sizeof(subscribed_peers));
+
+ if (err) {
+ LOG_ERR("Problem storing subscribed_peers (err %d)", err);
+ }
+ }
+}
+
+static void reset_subscribers(bool settings_store)
+{
+ for (size_t i = 0; i < ARRAY_SIZE(subscribed_peers); i++) {
+ struct subscribed_peer *sub = &subscribed_peers[i];
+
+ bt_addr_le_copy(&sub->addr, BT_ADDR_LE_NONE);
+ sub->peer_type = PEER_TYPE_COUNT;
+ sub->llpm_support = false;
+ }
+
+ if (settings_store) {
+ store_subscribed_peers();
+ }
+}
+
+static void add_subscriber(const struct ble_discovery_complete_event *event)
+{
+ const bt_addr_le_t *peer_addr = bt_conn_get_dst(bt_gatt_dm_conn_get(event->dm));
+ size_t i;
+
+ for (i = 0; i < ARRAY_SIZE(subscribed_peers); i++) {
+ struct subscribed_peer *sub = &subscribed_peers[i];
+
+ /* Already saved. */
+ if (!bt_addr_le_cmp(&sub->addr, peer_addr)) {
+ break;
+ }
+
+ /* Save data about new subscriber. */
+ if (!bt_addr_le_cmp(&sub->addr, BT_ADDR_LE_NONE)) {
+ bt_addr_le_copy(&sub->addr, peer_addr);
+ sub->peer_type = event->peer_type;
+ sub->llpm_support = event->peer_llpm_support;
+
+ store_subscribed_peers();
+ break;
+ }
+ }
+
+ /* Ensure peer was found. */
+ __ASSERT_NO_MSG(i < ARRAY_SIZE(subscribed_peers));
+}
+
+static void peer_discovery_start(struct bt_conn *conn)
+{
+ __ASSERT_NO_MSG(!discovering_peer_conn);
+ discovering_peer_conn = conn;
+ bt_conn_ref(discovering_peer_conn);
+}
+
+static void peer_discovery_end(const struct ble_discovery_complete_event *event)
+{
+ if (event) {
+ __ASSERT_NO_MSG(discovering_peer_conn == bt_gatt_dm_conn_get(event->dm));
+ add_subscriber(event);
+ }
+
+ __ASSERT_NO_MSG(discovering_peer_conn);
+ bt_conn_unref(discovering_peer_conn);
+ discovering_peer_conn = NULL;
+}
 
 static void verify_bond(const struct bt_bond_info *info, void *user_data)
 {
@@ -431,40 +505,15 @@ static void scan_connecting(struct bt_scan_device_info *device_info,
  struct bt_conn *conn)
 {
  LOG_INF("Connecting done");
- __ASSERT_NO_MSG(!discovering_peer_conn);
- discovering_peer_conn = conn;
- bt_conn_ref(discovering_peer_conn);
-}
 
-static int store_subscribed_peers(void)
-{
- if (IS_ENABLED(CONFIG_SETTINGS)) {
- char key[] = MODULE_NAME "/" SUBSCRIBED_PEERS_STORAGE_NAME;
- int err = settings_save_one(key, subscribed_peers, sizeof(subscribed_peers));
-
- if (err) {
- LOG_ERR("Problem storing subscribed_peers (err %d)", err);
- return err;
- }
- }
-
- return 0;
-}
-
-static void reset_subscribers(void)
-{
- for (size_t i = 0; i < ARRAY_SIZE(subscribed_peers); i++) {
- bt_addr_le_copy(&subscribed_peers[i].addr, BT_ADDR_LE_NONE);
- subscribed_peers[i].peer_type = PEER_TYPE_COUNT;
- subscribed_peers[i].llpm_support = false;
- }
+ peer_discovery_start(conn);
 }
 
 BT_SCAN_CB_INIT(scan_cb, scan_filter_match, NULL, scan_connecting_error, scan_connecting);
 
 static void scan_init(void)
 {
- reset_subscribers();
+ reset_subscribers(false);
 
  static const struct bt_le_scan_param sp = {
  .type = BT_LE_SCAN_TYPE_ACTIVE,
@@ -551,9 +600,9 @@ static bool handle_ble_peer_event(const struct ble_peer_event *event)
  case PEER_STATE_CONN_FAILED:
  case PEER_STATE_DISCONNECTED:
  if (discovering_peer_conn == event->id) {
- bt_conn_unref(discovering_peer_conn);
- discovering_peer_conn = NULL;
+ peer_discovery_end(NULL);
  }
+
  /* ble_state keeps reference to connection object.
  * Cannot create new connection now.
  */
@@ -573,8 +622,7 @@ static bool handle_ble_peer_operation_event(const struct ble_peer_operation_even
 {
  switch (event->op) {
  case PEER_OPERATION_ERASED:
- reset_subscribers();
- store_subscribed_peers();
+ reset_subscribers(true);
  /* Fall-through */
 
  case PEER_OPERATION_SCAN_REQUEST:
@@ -604,31 +652,7 @@ static bool handle_ble_peer_operation_event(const struct ble_peer_operation_even
 
 static bool handle_ble_discovery_complete_event(const struct ble_discovery_complete_event *event)
 {
- size_t i;
-
- for (i = 0; i < ARRAY_SIZE(subscribed_peers); i++) {
- /* Already saved. */
- if (!bt_addr_le_cmp(&subscribed_peers[i].addr,
- bt_conn_get_dst(discovering_peer_conn))) {
- break;
- }
-
- /* Save data about new subscriber. */
- if (!bt_addr_le_cmp(&subscribed_peers[i].addr, BT_ADDR_LE_NONE)) {
- bt_addr_le_copy(&subscribed_peers[i].addr,
- bt_conn_get_dst(discovering_peer_conn));
- subscribed_peers[i].peer_type =
- event->peer_type;
- subscribed_peers[i].llpm_support = event->peer_llpm_support;
- store_subscribed_peers();
- break;
- }
- }
-
- __ASSERT_NO_MSG(i < ARRAY_SIZE(subscribed_peers));
-
- bt_conn_unref(discovering_peer_conn);
- discovering_peer_conn = NULL;
+ peer_discovery_end(event);
 
  /* Cannot start scanning right after discovery - problems
  * establishing security - using delayed work as workaround.