[PATCH net-next 02/14] net: alx: Remove obsolete 32-bit DMA mask fallback

[Ruizhe Zhou]

The DMA API guarantees support for masks of 32 bits or wider and
explicitly identifies retrying a 32-bit mask after a 64-bit request as
incorrect:
https://docs.kernel.org/core-api/dma-api-howto.html#dma-addressing-capabilities

Remove the obsolete fallback while retaining the error check so that a
genuine DMA setup failure is still reported and aborts initialization.

Signed-off-by: Ruizhe Zhou <zhouruizhe@xxxxxxxxxxx>
---
 drivers/net/ethernet/atheros/alx/main.c | 13 +++++--------
 1 file changed, 5 insertions(+), 8 deletions(-)

diff --git a/drivers/net/ethernet/atheros/alx/main.c b/drivers/net/ethernet/atheros/alx/main.c
index ab262e66f986..3ca69fd14a5c 100644
--- a/drivers/net/ethernet/atheros/alx/main.c
+++ b/drivers/net/ethernet/atheros/alx/main.c
@@ -1727,15 +1727,12 @@ static int alx_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 	 * shared register for the high 32 bits, so only a single, aligned,
 	 * 4 GB physical address range can be used for descriptors.
 	 */
-	if (!dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(64))) {
-		dev_dbg(&pdev->dev, "DMA to 64-BIT addresses\n");
-	} else {
-		err = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
-		if (err) {
-			dev_err(&pdev->dev, "No usable DMA config, aborting\n");
-			goto out_pci_disable;
-		}
+	err = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(64));
+	if (err) {
+		dev_err(&pdev->dev, "No usable DMA config, aborting\n");
+		goto out_pci_disable;
 	}
+	dev_dbg(&pdev->dev, "DMA to 64-BIT addresses\n");
 
 	err = pci_request_mem_regions(pdev, alx_drv_name);
 	if (err) {
-- 
2.27.0