Gate's label in the control function

qiskit/circuit/library/standard_gates/multi_control_su2.py

@@ -20,6 +20,7 @@
 from qiskit.circuit.controlledgate import ControlledGate
 from qiskit.circuit.library.standard_gates.x import MCXVChain
 from qiskit.exceptions import QiskitError
+from qiskit.circuit._utils import _ctrl_state_to_int
 
 
 class MCSU2Gate(ControlledGate):
@@ -109,6 +110,34 @@ def inverse(self):
             ctrl_state=self.ctrl_state,
         )
 
+    def control(
+        self,
+        num_ctrl_qubits: int = 1,
+        label: Optional[str] = None,
+        ctrl_state: Optional[Union[str, int]] = None,
+    ):
+        """
+        Controlled version of this gate.
+        Args:
+            num_ctrl_qubits (int): number of control qubits.
+            label (str or None): An optional label for the gate [Default: None]
+            ctrl_state (int or str or None): control state expressed as integer,
+                string (e.g. '110'), or None. If None, use all 1s.
+        Returns:
+            ControlledGate: controlled version of this gate.
+        """
+        ctrl_state = _ctrl_state_to_int(ctrl_state, num_ctrl_qubits)
+        new_ctrl_state = (self.ctrl_state << num_ctrl_qubits) | ctrl_state
+        gate = MCSU2Gate(
+            su2_matrix=self.su2_matrix,
+            num_ctrl_qubits=num_ctrl_qubits + self.num_ctrl_qubits,
+            ctrl_state=new_ctrl_state,
+        )
+
+        gate.label = label
+
+        return gate
+
     @staticmethod
     def _check_su2(matrix):
         return isclose(np.linalg.det(matrix), 1.0)