usb: dwc3: ep0: use dwc3_request for ep0 requsts instead of usb_request

Instead of special functions and shortcuts for sending our internal
answers to the host we started doing what the gadget does and used the
public API for this. Since we only were using a few fields the
usb_request was enough. Later added the list handling in order to
synchronize the host / gadget events and now we require to have the
dwc3_request struct around our usb_request or else we touch memory that
does not belong to us. So this patch does this.
Reported-by: Partha Basak <p-basak2@ti.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Felipe Balbi <balbi@ti.com>

drivers/usb/dwc3/core.h

@@ -548,6 +548,20 @@ struct dwc3_hwparams {
 /* HWPARAMS1 */
 #define DWC3_NUM_INT(n)	(((n) & (0x3f << 15)) >> 15)
 
+struct dwc3_request {
+	struct usb_request	request;
+	struct list_head	list;
+	struct dwc3_ep		*dep;
+
+	u8			epnum;
+	struct dwc3_trb_hw	*trb;
+	dma_addr_t		trb_dma;
+
+	unsigned		direction:1;
+	unsigned		mapped:1;
+	unsigned		queued:1;
+};
+
 /**
  * struct dwc3 - representation of our controller
  * @ctrl_req: usb control request which is used for ep0
@@ -596,7 +610,7 @@ struct dwc3 {
 	dma_addr_t		ep0_trb_addr;
 	dma_addr_t		setup_buf_addr;
 	dma_addr_t		ep0_bounce_addr;
-	struct usb_request	ep0_usb_req;
+	struct dwc3_request	ep0_usb_req;
 	/* device lock */
 	spinlock_t		lock;
 	struct device		*dev;

drivers/usb/dwc3/ep0.c

@@ -302,10 +302,10 @@ static int dwc3_ep0_handle_status(struct dwc3 *dwc,
 
 	response_pkt = (__le16 *) dwc->setup_buf;
 	*response_pkt = cpu_to_le16(usb_status);
-	dwc->ep0_usb_req.length = sizeof(*response_pkt);
-	dwc->ep0_usb_req.dma = dwc->setup_buf_addr;
-	dwc->ep0_usb_req.complete = dwc3_ep0_status_cmpl;
-	return usb_ep_queue(&dwc->eps[0]->endpoint, &dwc->ep0_usb_req,
+	dwc->ep0_usb_req.request.length = sizeof(*response_pkt);
+	dwc->ep0_usb_req.request.dma = dwc->setup_buf_addr;
+	dwc->ep0_usb_req.request.complete = dwc3_ep0_status_cmpl;
+	return usb_ep_queue(&dwc->eps[0]->endpoint, &dwc->ep0_usb_req.request,
 			GFP_ATOMIC);
 }
 

drivers/usb/dwc3/gadget.h

@@ -79,19 +79,6 @@ struct dwc3_gadget_ep_cmd_params {
 
 /* -------------------------------------------------------------------------- */
 
-struct dwc3_request {
-	struct usb_request	request;
-	struct list_head	list;
-	struct dwc3_ep		*dep;
-
-	u8			epnum;
-	struct dwc3_trb_hw	*trb;
-	dma_addr_t		trb_dma;
-
-	unsigned		direction:1;
-	unsigned		mapped:1;
-	unsigned		queued:1;
-};
 #define to_dwc3_request(r)	(container_of(r, struct dwc3_request, request))
 
 static inline struct dwc3_request *next_request(struct list_head *list)