DMA-API: usb: use dma_set_coherent_mask()

The correct way for a driver to specify the coherent DMA mask is
not to directly access the field in the struct device, but to use
dma_set_coherent_mask().  Only arch and bus code should access this
member directly.

Convert all direct write accesses to using the correct API.

Acked-by: Felipe Balbi <balbi@ti.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/drivers/usb/host/ehci-orion.c b/drivers/usb/host/ehci-orion.c
index d1dfb9d..5870206 100644
--- a/drivers/usb/host/ehci-orion.c
+++ b/drivers/usb/host/ehci-orion.c
@@ -182,8 +182,9 @@
 	 */
 	if (!pdev->dev.dma_mask)
 		pdev->dev.dma_mask = &pdev->dev.coherent_dma_mask;
-	if (!pdev->dev.coherent_dma_mask)
-		pdev->dev.coherent_dma_mask = DMA_BIT_MASK(32);
+	err = dma_set_coherent_mask(&pdev->dev, DMA_BIT_MASK(32));
+	if (err)
+		goto err1;
 
 	if (!request_mem_region(res->start, resource_size(res),
 				ehci_orion_hc_driver.description)) {