> Is this safe? The driver is not using a threaded irq, and DMA termination
> may be called from the interrupt handler.

You are right, this will not work. Not my best day today, I overlooked
it for i2c-rcar and lost the note pointing out the same issue for
stm32f7 :(

> Have you tried triggering DMA termination, with lockdep enabled?

Nope. As the code didn't show signs of async nature, I assumed sync was
desired anyhow.