+static int b43legacy_dma_set_mask(struct b43legacy_wldev *dev, u64 mask)
+{
+ u64 orig_mask = mask;
+ bool fallback = 0;
+ 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 = ssb_dma_set_mask(dev->dev, mask);
+ if (!err)
+ break;
+ if (mask == DMA_64BIT_MASK) {
+ mask = DMA_32BIT_MASK;
+ fallback = 1;
+ continue;
+ }
+ if (mask == DMA_32BIT_MASK) {
+ mask = DMA_30BIT_MASK;
+ fallback = 1;
+ 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;
+}
+