mtd: rawnand: cadence: fix error code in cadence_nand_init()

Replace dma_request_channel() with dma_request_chan_by_mask() and use
helper functions to return proper error code instead of fixed -EBUSY.

Fixes: ec4ba01 ("mtd: rawnand: Add new Cadence NAND driver to MTD subsystem")
Cc: [email protected]
Signed-off-by: Niravkumar L Rabara <[email protected]>
Signed-off-by: Miquel Raynal <[email protected]>

Author: rabara

drivers/mtd/nand/raw/cadence-nand-controller.c

@@ -2904,11 +2904,10 @@ static int cadence_nand_init(struct cdns_nand_ctrl *cdns_ctrl)
 	dma_cap_set(DMA_MEMCPY, mask);
 
 	if (cdns_ctrl->caps1->has_dma) {
-		cdns_ctrl->dmac = dma_request_channel(mask, NULL, NULL);
-		if (!cdns_ctrl->dmac) {
-			dev_err(cdns_ctrl->dev,
-				"Unable to get a DMA channel\n");
-			ret = -EBUSY;
+		cdns_ctrl->dmac = dma_request_chan_by_mask(&mask);
+		if (IS_ERR(cdns_ctrl->dmac)) {
+			ret = dev_err_probe(cdns_ctrl->dev, PTR_ERR(cdns_ctrl->dmac),
+					    "%d: Failed to get a DMA channel\n", ret);
 			goto disable_irq;
 		}
 	}