Bluetooth: HFP_HF: Query subscriber number

Add function `bt_hfp_hf_query_subscriber` to query the AG subscriber
number.

Add callback `subscriber_number` to notify the result of the query of
the subscriber number information.

Signed-off-by: Lyle Zhu <[email protected]>

Author: lylezhu2012

include/zephyr/bluetooth/classic/hfp_hf.h

@@ -383,6 +383,39 @@ struct bt_hfp_hf_cb {
 	 *  @param number Value of `<Phone number>`.
 	 */
 	void (*request_phone_number)(struct bt_hfp_hf *hf, const char *number);
+
+	/** Query subscriber number callback
+	 *
+	 *  If this callback is provided it will be called whenever the
+	 *  result code `+CUNM: [<alpha>],<number>, <type>,[<speed> ,<service>]`
+	 *  is received from AG.
+	 *  `<alpha>`: This optional field is not supported, and shall be left
+	 *  blank.
+	 *  `<number>`: Quoted string containing the phone number in the format
+	 *  specified by `<type>`.
+	 *  `<type>` field specifies the format of the phone number provided,
+	 *  and can be one of the following values:
+	 *  - values 128-143: The phone number format may be a national or
+	 *  international format, and may contain prefix and/or escape digits.
+	 *  No changes on the number presentation are required.
+	 *  - values 144-159: The phone number format is an international
+	 *  number, including the country code prefix. If the plus sign ("+")
+	 *  is not included as part of the number and shall be added by the AG
+	 *  as needed.
+	 *  - values 160-175: National number. No prefix nor escape digits
+	 *  included.
+	 *  `<speed>`: This optional field is not supported, and shall be left
+	 *  blank.
+	 *  `<service>`: Indicates which service this phone number relates to.
+	 *  Shall be either 4 (voice) or 5 (fax).
+	 *
+	 *  @param hf HFP HF object.
+	 *  @param number Value of `<number>` without quotes.
+	 *  @param type Value of `<type>`.
+	 *  @param service Value of `<service>`.
+	 */
+	void (*subscriber_number)(struct bt_hfp_hf *hf, const char *number, uint8_t type,
+				  uint8_t service);
 };
 
 /** @brief Register HFP HF profile
@@ -805,6 +838,16 @@ int bt_hfp_hf_request_phone_number(struct bt_hfp_hf *hf);
  */
 int bt_hfp_hf_transmit_dtmf_code(struct bt_hfp_hf_call *call, char code);
 
+/** @brief Handsfree HF Query Subscriber Number Information
+ *
+ *  It allows HF to query the AG subscriber number by sending `AT+CNUM`.
+ *
+ *  @param hf HFP HF object.
+ *
+ *  @return 0 in case of success or negative value in case of error.
+ */
+int bt_hfp_hf_query_subscriber(struct bt_hfp_hf *hf);
+
 #ifdef __cplusplus
 }
 #endif

subsys/bluetooth/host/classic/hfp_hf.c

@@ -1603,6 +1603,45 @@ int chld_handle(struct at_client *hf_at)
 }
 #endif /* CONFIG_BT_HFP_HF_3WAY_CALL */
 
+static int cnum_handle(struct at_client *hf_at)
+{
+	struct bt_hfp_hf *hf = CONTAINER_OF(hf_at, struct bt_hfp_hf, at);
+	int err;
+	char *alpha;
+	char *number;
+	uint32_t type;
+	char *speed;
+	uint32_t service = 4;
+
+	alpha = at_get_raw_string(hf_at, NULL);
+	number = at_get_string(hf_at);
+	if (!number) {
+		LOG_INF("Cannot get number");
+		return -EINVAL;
+	}
+
+	err = at_get_number(hf_at, &type);
+	if (err) {
+		LOG_INF("Cannot get type");
+		return -EINVAL;
+	}
+
+	speed = at_get_raw_string(hf_at, NULL);
+
+	err = at_get_number(hf_at, &service);
+	if (err) {
+		LOG_INF("Cannot get service");
+	}
+
+	if (bt_hf->subscriber_number) {
+		bt_hf->subscriber_number(hf, number, (uint8_t)type, (uint8_t)service);
+	}
+
+	LOG_DBG("CNUM number %s type %d service %d", number, type, service);
+
+	return 0;
+}
+
 static const struct unsolicited {
 	const char *cmd;
 	enum at_cmd_type type;
@@ -1632,6 +1671,7 @@ static const struct unsolicited {
 #if defined(CONFIG_BT_HFP_HF_VOICE_RECG)
 	{ "BVRA", AT_CMD_TYPE_UNSOLICITED, bvra_handle },
 #endif /* CONFIG_BT_HFP_HF_VOICE_RECG */
+	{ "CNUM", AT_CMD_TYPE_UNSOLICITED, cnum_handle },
 };
 
 static const struct unsolicited *hfp_hf_unsol_lookup(struct at_client *hf_at)
@@ -2387,6 +2427,40 @@ int bt_hfp_hf_transmit_dtmf_code(struct bt_hfp_hf_call *call, char code)
 	return err;
 }
 
+static int cnum_finish(struct at_client *hf_at, enum at_result result,
+		   enum at_cme cme_err)
+{
+	struct bt_hfp_hf *hf = CONTAINER_OF(hf_at, struct bt_hfp_hf, at);
+
+	LOG_DBG("AT+CNUM (result %d) on %p", result, hf);
+
+	return 0;
+}
+
+int bt_hfp_hf_query_subscriber(struct bt_hfp_hf *hf)
+{
+	int err;
+
+	LOG_DBG("");
+
+	if (!hf) {
+		LOG_ERR("No HF connection found");
+		return -ENOTCONN;
+	}
+
+	if (!atomic_test_bit(hf->flags, BT_HFP_HF_FLAG_CONNECTED)) {
+		LOG_ERR("SLC is not established on %p", hf);
+		return -ENOTCONN;
+	}
+
+	err = hfp_hf_send_cmd(hf, NULL, cnum_finish, "AT+CNUM");
+	if (err < 0) {
+		LOG_ERR("Fail to query subscriber number information on %p", hf);
+	}
+
+	return err;
+}
+
 static int ata_finish(struct at_client *hf_at, enum at_result result,
 		   enum at_cme cme_err)
 {