def set_input_gain(self, gain):
        """Sets the system capture gain.

        @param gain: the capture gain in db*100 (100 = 1dB)

        """
        cras_utils.set_capture_gain(gain)
def cras_rms_test_setup():
    """Setups for the cras_rms_tests.

    To make sure the line_out-to-mic_in path is all green.
    """
    # TODO(owenlin): Now, the nodes are choosed by chrome.
    #                We should do it here.
    cras_utils.set_system_volume(_DEFAULT_PLAYBACK_VOLUME)
    cras_utils.set_selected_output_node_volume(_DEFAULT_PLAYBACK_VOLUME)

    cras_utils.set_capture_gain(_DEFAULT_CAPTURE_GAIN)

    cras_utils.set_system_mute(False)
    cras_utils.set_capture_mute(False)