You can play the audio data over I2S only, which interfaces with an audio codec AK4954A as shown in this block diagram at page# 03 :
I am saying so because Audio interface which is acting as input to Mono Speaker or Stereo Line-out is taking its data in I2S format only using SDTO/SDTI pins
Can I send the raw data in WAVE through the I2S to the CODEC or does data need to be converted to I2S format?
In this Code Example CE222221_TFT_VoiceRecorder available at this link:
In this CE the audio data is send in I2S format , so I think data needs to be converted in I2S format.
We have not tested sending Wave through I2S directly.