hfp_hf: send custom AT command with hfp_hf_send_at_command

CHANGELOG.md

@@ -9,9 +9,10 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
 ## Unreleased
 
 ### Added
+- HFP HF: send custom AT command with hfp_hf_send_at_command
 - port: CMake build files in all windows-* ports allow to use Visual Studio 2022
 - embedded audio: mono audio is played on both channels if HAVE_HAL_AUDIO_SINK_STEREO_ONLY is defined
-
+ 
 ### Fixed
 
 ### Changed

src/classic/hfp.h

@@ -222,7 +222,8 @@ typedef enum {
     HFP_CMD_RESPONSE_AND_HOLD_QUERY,
     HFP_CMD_RESPONSE_AND_HOLD_COMMAND,
     HFP_CMD_RESPONSE_AND_HOLD_STATUS,
-    HFP_CMD_HF_INDICATOR_STATUS
+    HFP_CMD_HF_INDICATOR_STATUS,
+    HFP_CMD_CUSTOM_MESSAGE
 } hfp_command_t;
  
 
@@ -631,7 +632,10 @@ typedef struct hfp_connection {
     uint8_t send_ag_status_indicators;
     uint8_t send_ag_indicators_segment;
     uint8_t send_response_and_hold_status;  // 0 - don't send. BRTH:0 == 1, ..
-    
+
+    // HF: AT Command, AG: Unsolicited Result Code
+    const char * send_custom_message;
+
     bool emit_vra_enabled_after_audio_established;
     // AG only
     uint8_t change_in_band_ring_tone_setting;

src/classic/hfp_hf.c

@@ -1049,6 +1049,15 @@ static void hfp_hf_run_for_context(hfp_connection_t * hfp_connection){
         }
     }
 
+    if (hfp_connection->send_custom_message != NULL){
+        const char * message = hfp_connection->send_custom_message;
+        hfp_connection->send_custom_message = NULL;
+        hfp_connection->ok_pending = 1;
+        hfp_connection->response_pending_for_command = HFP_CMD_CUSTOM_MESSAGE;
+        send_str_over_rfcomm(hfp_connection->rfcomm_cid, message);
+        return;
+    }
+
     if (done) return;
     // deal with disconnect
     switch (hfp_connection->state){ 
@@ -1124,6 +1133,9 @@ static bool hfp_hf_switch_on_ok_pending(hfp_connection_t *hfp_connection, uint8_
         case HFP_CMD_TURN_OFF_EC_AND_NR:
             hfp_emit_event(hfp_connection, HFP_SUBEVENT_ECHO_CANCELING_AND_NOISE_REDUCTION_DEACTIVATE, status);
             break;
+        case HFP_CMD_CUSTOM_MESSAGE:
+            hfp_emit_event(hfp_connection, HFP_SUBEVENT_COMPLETE, status);
+            break;
         default:
             event_emited = false;
     
@@ -2171,6 +2183,19 @@ uint8_t hfp_hf_set_hf_indicator(hci_con_handle_t acl_handle, int assigned_number
     return ERROR_CODE_SUCCESS;
 }
 
+uint8_t hfp_hf_send_at_command(hci_con_handle_t acl_handle, const char * at_command){
+    hfp_connection_t * hfp_connection = get_hfp_hf_connection_context_for_acl_handle(acl_handle);
+    if (!hfp_connection) {
+        return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
+    }
+    if (hfp_connection->send_custom_message != NULL){
+        return ERROR_CODE_COMMAND_DISALLOWED;
+    }
+    hfp_connection->send_custom_message = at_command;
+    hfp_hf_run_for_context(hfp_connection);
+    return ERROR_CODE_SUCCESS;
+}
+
 int hfp_hf_in_band_ringtone_active(hci_con_handle_t acl_handle){
     hfp_connection_t * hfp_connection = get_hfp_hf_connection_context_for_acl_handle(acl_handle);
     if (!hfp_connection) {

src/classic/hfp_hf.h

@@ -520,6 +520,18 @@ uint8_t hfp_hf_set_hf_indicator(hci_con_handle_t acl_handle, int assigned_number
  */
 int hfp_hf_in_band_ringtone_active(hci_con_handle_t acl_handle);
 
+/*
+ * @brief Send AT command (most likely a vendor-specific command not part of standard HFP).
+ * @note  Result (OK/ERROR) is reported via HFP_SUBEVENT_COMPLETE
+ *        To receive potential unsolicited result code, add ENABLE_HFP_AT_MESSAGES to get all message via HFP_SUBEVENT_AT_MESSAGE_RECEIVED
+ *
+ * @param at_command to send
+ * @return status ERROR_CODE_SUCCESS if successful, otherwise:
+ *              - ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER if connection does not exist, or
+ *              - ERROR_CODE_COMMAND_DISALLOWED if extended audio gateway error report is disabled
+ */
+uint8_t hfp_hf_send_at_command(hci_con_handle_t hfp_ag_acl_handle, const char * at_command);
+
 /**
  * @brief De-Init HFP HF
  */