mmc: tmio: Configure DMA slave bus width

Even though some implementations support 4-bytes data register access,
the tmio driver never configures the hardware in such a way and always
performs 2-bytes accesses. Hardcode the DMA transfer size to 2 bytes.
Signed-off-by: NLaurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>

drivers/mmc/host/tmio_mmc_dma.c

@@ -294,6 +294,7 @@ void tmio_mmc_request_dma(struct tmio_mmc_host *host, struct tmio_mmc_data *pdat
 			cfg.slave_id = pdata->dma->slave_id_tx;
 		cfg.direction = DMA_MEM_TO_DEV;
 		cfg.dst_addr = res->start + (CTL_SD_DATA_PORT << host->pdata->bus_shift);
+		cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES;
 		cfg.src_addr = 0;
 		ret = dmaengine_slave_config(host->chan_tx, &cfg);
 		if (ret < 0)
@@ -312,6 +313,7 @@ void tmio_mmc_request_dma(struct tmio_mmc_host *host, struct tmio_mmc_data *pdat
 			cfg.slave_id = pdata->dma->slave_id_rx;
 		cfg.direction = DMA_DEV_TO_MEM;
 		cfg.src_addr = cfg.dst_addr;
+		cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES;
 		cfg.dst_addr = 0;
 		ret = dmaengine_slave_config(host->chan_rx, &cfg);
 		if (ret < 0)