of/device: Update dma_range_map only when dev has valid dma-ranges

The commit e0d072782c73 ("dma-mapping: introduce DMA range map,
supplanting dma_pfn_offset") always update dma_range_map even though it was
already set, like in the sunxi_mbus driver. the issue is reported at [1].
This patch avoid this(Updating it only when dev has valid dma-ranges).

Meanwhile, dma_range_map contains the devices' dma_ranges information,
This patch moves dma_range_map before of_iommu_configure. The iommu
driver may need to know the dma_address requirements of its iommu
consumer devices.

[1] https://lore.kernel.org/linux-arm-kernel/[e-mail]/

CC: Frank Rowand <[e-mail]>
Fixes: e0d072782c73 ("dma-mapping: introduce DMA range map, supplanting dma_pfn_offset"),
Suggested-by: Robin Murphy <[e-mail]>
Signed-off-by: Yong Wu <[e-mail]>
Signed-off-by: Paul Kocialkowski <[e-mail]>
Reviewed-by: Rob Herring <[e-mail]>
Reviewed-by: Robin Murphy <[e-mail]>
Signed-off-by: Rob Herring <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]

drivers/of/device.c

···
 	mask = DMA_BIT_MASK(ilog2(end) + 1);
 	dev->coherent_dma_mask &= mask;
 	*dev->dma_mask &= mask;
-	/* ...but only set bus limit if we found valid dma-ranges earlier */
-	if (!ret)
+	/* ...but only set bus limit and range map if we found valid dma-ranges earlier */
+	if (!ret) {
 		dev->bus_dma_limit = end;
+		dev->dma_range_map = map;
+	}
 
 	coherent = of_dma_is_coherent(np);
 	dev_dbg(dev, "device is%sdma coherent\n",
···
 
 	iommu = of_iommu_configure(dev, np, id);
 	if (PTR_ERR(iommu) == -EPROBE_DEFER) {
+		/* Don't touch range map if it wasn't set from a valid dma-ranges */
+		if (!ret)
+			dev->dma_range_map = NULL;
 		kfree(map);
 		return -EPROBE_DEFER;
 	}
···
 
 	arch_setup_dma_ops(dev, dma_start, size, iommu, coherent);
 
-	dev->dma_range_map = map;
 	return 0;
 }
 EXPORT_SYMBOL_GPL(of_dma_configure_id);