spi: spi-fsl-dspi: Fix SPI transfer issue when using multiple SPI_IOC_MESSAGE

Current DMA implementation had a bug where the DMA transfer would
exit the loop in dspi_transfer_one_message after the completion of
a single transfer. This results in a multi message transfer submitted
with SPI_IOC_MESSAGE to terminate incorrectly without an error.
Signed-off-by: NSanchayan Maity <maitysanchayan@gmail.com>
Reviewed-by: NStefan Agner <stefan@agner.ch>
Signed-off-by: NMark Brown <broonie@kernel.org>

drivers/spi/spi-fsl-dspi.c

@@ -714,7 +714,7 @@ static int dspi_transfer_one_message(struct spi_master *master,
 				SPI_RSER_TFFFE | SPI_RSER_TFFFD |
 				SPI_RSER_RFDFE | SPI_RSER_RFDFD);
 			status = dspi_dma_xfer(dspi);
-			goto out;
+			break;
 		default:
 			dev_err(&dspi->pdev->dev, "unsupported trans_mode %u\n",
 				trans_mode);
@@ -722,9 +722,13 @@ static int dspi_transfer_one_message(struct spi_master *master,
 			goto out;
 		}
 
-		if (wait_event_interruptible(dspi->waitq, dspi->waitflags))
-			dev_err(&dspi->pdev->dev, "wait transfer complete fail!\n");
-		dspi->waitflags = 0;
+		if (trans_mode != DSPI_DMA_MODE) {
+			if (wait_event_interruptible(dspi->waitq,
+						dspi->waitflags))
+				dev_err(&dspi->pdev->dev,
+					"wait transfer complete fail!\n");
+			dspi->waitflags = 0;
+		}
 
 		if (transfer->delay_usecs)
 			udelay(transfer->delay_usecs);