mmc: core: Only set maximum DMA segment size if DMA is supported

Since upstream commit 334304a ("dma-mapping: don't return errors
from dma_set_max_seg_size") calling dma_set_max_seg_size() on a device
not supporting DMA results in a warning traceback. This is seen when
booting the sifive_u machine from SD. The underlying SPI controller
(sifive,spi0 compatible) explicitly sets dma_mask to NULL.

Avoid the backtrace by only calling dma_set_max_seg_size() if DMA is
supported.

Signed-off-by: Guenter Roeck <[email protected]>
Reviewed-by: Christoph Hellwig <[email protected]>
Reviewed-by: Robin Murphy <[email protected]>
Tested-by: Geert Uytterhoeven <[email protected]>
Fixes: 334304a ("dma-mapping: don't return errors from dma_set_max_seg_size")
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Ulf Hansson <[email protected]>

Author: groeck

drivers/mmc/core/queue.c

@@ -388,7 +388,8 @@ static struct gendisk *mmc_alloc_disk(struct mmc_queue *mq,
 
 	blk_queue_rq_timeout(mq->queue, 60 * HZ);
 
-	dma_set_max_seg_size(mmc_dev(host), queue_max_segment_size(mq->queue));
+	if (mmc_dev(host)->dma_parms)
+		dma_set_max_seg_size(mmc_dev(host), queue_max_segment_size(mq->queue));
 
 	INIT_WORK(&mq->recovery_work, mmc_mq_recovery_handler);
 	INIT_WORK(&mq->complete_work, mmc_blk_mq_complete_work);