usb: dwc3: allocate setup_buf with dma_alloc_coherent()

Since setup_buf is also consumed by hardware DMA, aligns it's
allocation like other hardware buffers by introduce setup_buf_addr
populated by dma_alloc_coherent(), and use it to pass the physical
address of the buffer to the hardware.

Reviewed-by: Mattijs Korpershoek <mkorpershoek@baylibre.com>
Reviewed-by: Marek Vasut <marex@denx.de>
Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>
diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h
index 7374ce9..b572ea3 100644
--- a/drivers/usb/dwc3/core.h
+++ b/drivers/usb/dwc3/core.h
@@ -670,6 +670,7 @@
  * @ep0_trb: dma address of ep0_trb
  * @ep0_usb_req: dummy req used while handling STD USB requests
  * @ep0_bounce_addr: dma address of ep0_bounce
+ * @setup_buf_addr: dma address of setup_buf
  * @scratch_addr: dma address of scratchbuf
  * @lock: for synchronizing
  * @dev: pointer to our struct device
@@ -757,6 +758,7 @@
 	dma_addr_t		ep0_trb_addr;
 	dma_addr_t		ep0_bounce_addr;
 	dma_addr_t		scratch_addr;
+	dma_addr_t		setup_buf_addr;
 	struct dwc3_request	ep0_usb_req;
 
 	/* device lock */
diff --git a/drivers/usb/dwc3/ep0.c b/drivers/usb/dwc3/ep0.c
index 24f516a..8ba5fcd 100644
--- a/drivers/usb/dwc3/ep0.c
+++ b/drivers/usb/dwc3/ep0.c
@@ -380,7 +380,7 @@
 	dep = dwc->eps[0];
 	dwc->ep0_usb_req.dep = dep;
 	dwc->ep0_usb_req.request.length = sizeof(*response_pkt);
-	dwc->ep0_usb_req.request.buf = dwc->setup_buf;
+	dwc->ep0_usb_req.request.buf = (void *)dwc->setup_buf_addr;
 	dwc->ep0_usb_req.request.complete = dwc3_ep0_status_cmpl;
 
 	return __dwc3_gadget_ep0_queue(dep, &dwc->ep0_usb_req);
@@ -662,7 +662,7 @@
 	dep = dwc->eps[0];
 	dwc->ep0_usb_req.dep = dep;
 	dwc->ep0_usb_req.request.length = dep->endpoint.maxpacket;
-	dwc->ep0_usb_req.request.buf = dwc->setup_buf;
+	dwc->ep0_usb_req.request.buf = (void *)dwc->setup_buf_addr;
 	dwc->ep0_usb_req.request.complete = dwc3_ep0_set_sel_cmpl;
 
 	return __dwc3_gadget_ep0_queue(dep, &dwc->ep0_usb_req);
diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index fe33e30..19c3a5f 100644
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -2653,8 +2653,8 @@
 		goto err1;
 	}
 
-	dwc->setup_buf = memalign(CONFIG_SYS_CACHELINE_SIZE,
-				  DWC3_EP0_BOUNCE_SIZE);
+	dwc->setup_buf = dma_alloc_coherent(DWC3_EP0_BOUNCE_SIZE,
+					(unsigned long *)&dwc->setup_buf_addr);
 	if (!dwc->setup_buf) {
 		ret = -ENOMEM;
 		goto err2;
@@ -2701,7 +2701,7 @@
 	dma_free_coherent(dwc->ep0_bounce);
 
 err3:
-	kfree(dwc->setup_buf);
+	dma_free_coherent(dwc->setup_buf);
 
 err2:
 	dma_free_coherent(dwc->ep0_trb);
@@ -2723,7 +2723,7 @@
 
 	dma_free_coherent(dwc->ep0_bounce);
 
-	kfree(dwc->setup_buf);
+	dma_free_coherent(dwc->setup_buf);
 
 	dma_free_coherent(dwc->ep0_trb);