On Wed, Jul 17, 2019 at 11:16:01PM +0200, Stefan Wahren wrote:

> +	/* check if we got interrupt enabled */
> +	if (!(bcm2835_rd(bs, BCM2835_SPI_CS) & BCM2835_SPI_CS_INTR))
> +		return IRQ_NONE;
> +

Is that checking if the interrupt is enabled or if it is asserted?