db2b927f86
The dmas property is used to hold the dmaengine channel used for audio output. Older device trees were missing that property, so if it's not there we disable the audio output entirely. However, some overlays have set an empty value to that property, mostly to workaround the fact that overlays cannot remove a property. Let's add a test for that case and if it's empty, let's disable it as well. Cc: <stable@vger.kernel.org> Signed-off-by: Phil Elwell <phil@raspberrypi.org> Link: https://lore.kernel.org/r/20220613144800.326124-18-maxime@cerno.tech Signed-off-by: Maxime Ripard <maxime@cerno.tech>