vchan_free_chan_resources(to_virt_chan(chan));
 }
 
-static struct dma_async_tx_descriptor *pl08x_prep_dma_interrupt(
-               struct dma_chan *chan, unsigned long flags)
-{
-       struct dma_async_tx_descriptor *retval = NULL;
-
-       return retval;
-}
-
 /*
  * Code accessing dma_async_is_complete() in a tight loop may give problems.
  * If slaves are relying on interrupts to signal completion this function
        pl08x->memcpy.dev = &adev->dev;
        pl08x->memcpy.device_free_chan_resources = pl08x_free_chan_resources;
        pl08x->memcpy.device_prep_dma_memcpy = pl08x_prep_dma_memcpy;
-       pl08x->memcpy.device_prep_dma_interrupt = pl08x_prep_dma_interrupt;
        pl08x->memcpy.device_tx_status = pl08x_dma_tx_status;
        pl08x->memcpy.device_issue_pending = pl08x_issue_pending;
        pl08x->memcpy.device_config = pl08x_config;
                pl08x->slave.dev = &adev->dev;
                pl08x->slave.device_free_chan_resources =
                        pl08x_free_chan_resources;
-               pl08x->slave.device_prep_dma_interrupt =
-                       pl08x_prep_dma_interrupt;
                pl08x->slave.device_tx_status = pl08x_dma_tx_status;
                pl08x->slave.device_issue_pending = pl08x_issue_pending;
                pl08x->slave.device_prep_slave_sg = pl08x_prep_slave_sg;