b43legacy: remove b43legacy_dma_set_mask

These days drivers are not required to fallback to smaller DMA masks,
but can just set the largest mask they support, removing the need for
this trial and error logic.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Larry Finger <Larry.Finger@lwfinger.net>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

drivers/net/wireless/broadcom/b43legacy/dma.c

@@ -784,43 +784,6 @@ void b43legacy_dma_free(struct b43legacy_wldev *dev)
 	dma->tx_ring0 = NULL;
 }
 
-static int b43legacy_dma_set_mask(struct b43legacy_wldev *dev, u64 mask)
-{
-	u64 orig_mask = mask;
-	bool fallback = false;
-	int err;
-
-	/* Try to set the DMA mask. If it fails, try falling back to a
-	 * lower mask, as we can always also support a lower one. */
-	while (1) {
-		err = dma_set_mask_and_coherent(dev->dev->dma_dev, mask);
-		if (!err)
-			break;
-		if (mask == DMA_BIT_MASK(64)) {
-			mask = DMA_BIT_MASK(32);
-			fallback = true;
-			continue;
-		}
-		if (mask == DMA_BIT_MASK(32)) {
-			mask = DMA_BIT_MASK(30);
-			fallback = true;
-			continue;
-		}
-		b43legacyerr(dev->wl, "The machine/kernel does not support "
-		       "the required %u-bit DMA mask\n",
-		       (unsigned int)dma_mask_to_engine_type(orig_mask));
-		return -EOPNOTSUPP;
-	}
-	if (fallback) {
-		b43legacyinfo(dev->wl, "DMA mask fallback from %u-bit to %u-"
-			"bit\n",
-			(unsigned int)dma_mask_to_engine_type(orig_mask),
-			(unsigned int)dma_mask_to_engine_type(mask));
-	}
-
-	return 0;
-}
-
 int b43legacy_dma_init(struct b43legacy_wldev *dev)
 {
 	struct b43legacy_dma *dma = &dev->dma;
@@ -831,7 +794,7 @@ int b43legacy_dma_init(struct b43legacy_wldev *dev)
 
 	dmamask = supported_dma_mask(dev);
 	type = dma_mask_to_engine_type(dmamask);
-	err = b43legacy_dma_set_mask(dev, dmamask);
+	err = dma_set_mask_and_coherent(dev->dev->dma_dev, dmamask);
 	if (err) {
 #ifdef CONFIG_B43LEGACY_PIO
 		b43legacywarn(dev->wl, "DMA for this device not supported. "