usb: uhci: Add Aspeed AST2700 support

Unlike earlier Aspeed SoCs (AST2400/2500/2600) which are limited to
32-bit DMA addressing, the UHCI controller in AST2700 supports 64-bit
DMA. Update the platform UHCI driver to select the appropriate DMA
mask based on the device tree compatible string.

Signed-off-by: Ryan Chen <[e-mail]>
Reviewed-by: Alan Stern <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

drivers/usb/host/uhci-platform.c

···
 	.hub_control =		uhci_hub_control,
 };
 
+static const u64 dma_mask_32 = DMA_BIT_MASK(32);
+static const u64 dma_mask_64 = DMA_BIT_MASK(64);
+
 static int uhci_hcd_platform_probe(struct platform_device *pdev)
 {
 	struct device_node *np = pdev->dev.of_node;
+	const u64 *dma_mask_ptr;
 	struct usb_hcd *hcd;
 	struct uhci_hcd	*uhci;
 	struct resource *res;
···
 	 * Since shared usb code relies on it, set it here for now.
 	 * Once we have dma capability bindings this can go away.
 	 */
-	ret = dma_coerce_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
+	dma_mask_ptr = (u64 *)of_device_get_match_data(&pdev->dev);
+	if (!dma_mask_ptr)
+		dma_mask_ptr = &dma_mask_32;
+
+	ret = dma_coerce_mask_and_coherent(&pdev->dev, *dma_mask_ptr);
 	if (ret)
 		return ret;
 
···
 		}
 		if (of_device_is_compatible(np, "aspeed,ast2400-uhci") ||
 		    of_device_is_compatible(np, "aspeed,ast2500-uhci") ||
-		    of_device_is_compatible(np, "aspeed,ast2600-uhci")) {
+		    of_device_is_compatible(np, "aspeed,ast2600-uhci") ||
+		    of_device_is_compatible(np, "aspeed,ast2700-uhci")) {
 			uhci->is_aspeed = 1;
 			dev_info(&pdev->dev,
 				 "Enabled Aspeed implementation workarounds\n");
···
 static const struct of_device_id platform_uhci_ids[] = {
 	{ .compatible = "generic-uhci", },
 	{ .compatible = "platform-uhci", },
+	{ .compatible = "aspeed,ast2700-uhci", .data = &dma_mask_64},
 	{}
 };
 MODULE_DEVICE_TABLE(of, platform_uhci_ids);