[PATCH v4 1/3] usb: dwc3: allocate setup_buf with dma_alloc_coherent()

[Neil Armstrong]

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 at baylibre.com>
Reviewed-by: Marek Vasut <marex at denx.de>
Signed-off-by: Neil Armstrong <neil.armstrong at linaro.org>
---
 drivers/usb/dwc3/core.h   | 2 ++
 drivers/usb/dwc3/ep0.c    | 4 ++--
 drivers/usb/dwc3/gadget.c | 8 ++++----
 3 files changed, 8 insertions(+), 6 deletions(-)

diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h
index 7374ce950da..b572ea340c8 100644
--- a/drivers/usb/dwc3/core.h
+++ b/drivers/usb/dwc3/core.h
@@ -670,6 +670,7 @@ struct dwc3_scratchpad_array {
  * @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 @@ struct dwc3 {
 	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 24f516a131b..8ba5fcd5312 100644
--- a/drivers/usb/dwc3/ep0.c
+++ b/drivers/usb/dwc3/ep0.c
@@ -380,7 +380,7 @@ static int dwc3_ep0_handle_status(struct dwc3 *dwc,
 	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 @@ static int dwc3_ep0_set_sel(struct dwc3 *dwc, struct usb_ctrlrequest *ctrl)
 	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 fe33e307d3e..19c3a5f5e58 100644
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -2653,8 +2653,8 @@ int dwc3_gadget_init(struct dwc3 *dwc)
 		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 @@ err4:
 	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 @@ void dwc3_gadget_exit(struct dwc3 *dwc)
 
 	dma_free_coherent(dwc->ep0_bounce);
 
-	kfree(dwc->setup_buf);
+	dma_free_coherent(dwc->setup_buf);
 
 	dma_free_coherent(dwc->ep0_trb);
 

-- 
2.34.1