Blackfin SPI Driver: do not check for SPI errors if DMA itself did not flag any

We only need to check SPI error when DMA failes, cause that is the DMA IRQ
handling routine.
Signed-off-by: NMike Frysinger <vapier.adi@gmail.com>
Signed-off-by: NBryan Wu <cooloney@kernel.org>
Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

drivers/spi/spi_bfin5xx.c

@@ -587,7 +587,7 @@ static irqreturn_t dma_irq_handler(int irq, void *dev_id)
 	while (!(read_STAT(drv_data) & SPIF))
 		cpu_relax();
 
-	if (spistat & RBSY) {
+	if ((dmastat & DMA_ERR) && (spistat & RBSY)) {
 		msg->state = ERROR_STATE;
 		dev_err(&drv_data->pdev->dev, "dma receive: fifo/buffer overflow\n");
 	} else {