• Simon Ser's avatar
    tests/kms_chamelium: add dp-audio test · 311baff1
    Simon Ser authored
    This new test ensures DisplayPort audio works by using the Chamelium.
    
    It enables the DisplayPort output and sends an audio signal containing a set of
    frequencies we choose to all HDMI/DisplayPort audio devices. It starts
    recording audio on the Chamelium device and uses the stream server to retrieve
    captured audio pages. It then checks that the capture audio signal contains the
    frequencies we sent, and only those, by computing a FFT.
    
    A new library has been added to libigt to communicate with the stream server.
    It implements a simple custom TCP protocol.
    
    In case the test fails, a WAV file with the captured data is saved on disk.
    
    Right now the test has a few limitations:
    
    - Only the first channel is checked
    - IGT only generates audio with a single sampling rate (48 KHz)
    - Audio data is not captured in real-time
    
    These limitations will be lifted in future patches.
    
    PulseAudio must not run during the tests since ALSA is used directly. To ensure
    this, edit /etc/pulse/client.conf and add `autospawn=no`. Then run
    `pulseaudio --kill`.
    
    This commit deletes the existing audio tests. They weren't run and required an
    exotic configuration (HDMI audio splitter, dummy HDMI sink and a line-in port
    on the DUT).
    
    This patch also changes lib/igt_audio to use uint16_t instead of short. The
    rationale is:
    
    - The standard says a short is at least 16 bit wide, but a short can be
      larger (in practice it won't happen, but better use types correctly)
    - It makes it clearer that the audio format is S16_LE, since "16" is
      in the type name.
    
    This patch depends on the following Chameleon bugs:
    
    - https://crbug.com/948060
    - https://crbug.com/950857Signed-off-by: 's avatarSimon Ser <simon.ser@intel.com>
    Reviewed-by: 's avatarMartin Peres <martin.peres@linux.intel.com>
    311baff1