[PATCH RFC 02/12] usb: xhci: pass physical device to DMA API

[Ahmad Fatoum]

The xHCI device is just a child of the DWC3 with no DT node assigned.
As such, it lacks all DMA settings that may be set in the DT.
Fix this by using the hardware device instead in case the xHCI lacks
its own DT node.

Signed-off-by: Ahmad Fatoum <a.fatoum at pengutronix.de>
---
 drivers/usb/host/xhci-ring.c | 8 ++++----
 drivers/usb/host/xhci.c      | 6 +++++-
 2 files changed, 9 insertions(+), 5 deletions(-)

diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c
index 60764222af3d..0abe8a67a392 100644
--- a/drivers/usb/host/xhci-ring.c
+++ b/drivers/usb/host/xhci-ring.c
@@ -594,7 +594,7 @@ int xhci_bulk_tx(struct usb_device *udev, unsigned long pipe,
 		memcpy(bounce, buffer, length);
 	}
 
-	map = addr = dma_map_single(ctrl->dev, bounce, length, direction);
+	map = addr = dma_map_single(ctrl->host.hw_dev, bounce, length, direction);
 
 	dev_dbg(&udev->dev, "pipe=0x%lx, buffer=%p, length=%d\n",
 		pipe, buffer, length);
@@ -740,7 +740,7 @@ int xhci_bulk_tx(struct usb_device *udev, unsigned long pipe,
 	record_transfer_result(udev, event, length);
 	xhci_acknowledge_event(ctrl);
 
-	dma_unmap_single(ctrl->dev, map, length, direction);
+	dma_unmap_single(ctrl->host.hw_dev, map, length, direction);
 
 	if (usb_pipein(pipe))
 		memcpy(buffer, bounce, length);
@@ -895,7 +895,7 @@ int xhci_ctrl_tx(struct usb_device *udev, unsigned long pipe,
 	if (length > 0) {
 		if (req->requesttype & USB_DIR_IN)
 			field |= TRB_DIR_IN;
-		map = buf_64 = dma_map_single(ctrl->dev, buffer, length, direction);
+		map = buf_64 = dma_map_single(ctrl->host.hw_dev, buffer, length, direction);
 
 		trb_fields[0] = lower_32_bits(buf_64);
 		trb_fields[1] = upper_32_bits(buf_64);
@@ -947,7 +947,7 @@ int xhci_ctrl_tx(struct usb_device *udev, unsigned long pipe,
 
 	/* Invalidate buffer to make it available to usb-core */
 	if (length > 0)
-		dma_unmap_single(ctrl->dev, map, length, direction);
+		dma_unmap_single(ctrl->host.hw_dev, map, length, direction);
 
 	if (GET_COMP_CODE(le32_to_cpu(event->trans_event.transfer_len))
 			== COMP_SHORT_TX) {
diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
index 55f51ca95192..930bb4b6c608 100644
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -1359,7 +1359,11 @@ int xhci_register(struct xhci_ctrl *ctrl)
 	 */
 	host->no_desc_before_addr = true;
 
-	host->hw_dev = dev;
+	/*
+	 * If xHCI doesn't have our own DT node, it'll be a child of a
+	 * physical USB host controller device that should be used for DMA
+	 */
+	host->hw_dev = dev_of_node(dev) ? dev : dev->parent;
 	host->submit_int_msg = xhci_submit_int_msg;
 	host->submit_control_msg = xhci_submit_control_msg;
 	host->submit_bulk_msg = xhci_submit_bulk_msg;
-- 
2.30.2