Merge "usb: dwc3: Add support to LPM L1 remote wakeup for ep0 endpoints"

drivers/usb/dwc3/core.h

@@ -1021,6 +1021,8 @@ struct dwc3 {
 	unsigned                irq_event_count[MAX_INTR_STATS];
 	unsigned                irq_dbg_index;
 
+	unsigned long		l1_remote_wakeup_cnt;
+
 	wait_queue_head_t	wait_linkstate;
 };
 

drivers/usb/dwc3/debugfs.c

@@ -1180,9 +1180,12 @@ static int dwc3_gadget_int_events_show(struct seq_file *s, void *unused)
 		seq_printf(s, "%d\t", dwc->bh_completion_time[i]);
 	seq_putc(s, '\n');
 
-	seq_printf(s, "t_pwr evt irq : %lld\t",
+	seq_printf(s, "t_pwr evt irq : %lld\n",
 			ktime_to_us(dwc->t_pwr_evt_irq));
 
+	seq_printf(s, "l1_remote_wakeup_cnt : %lu\n",
+		dwc->l1_remote_wakeup_cnt);
+
 	spin_unlock_irqrestore(&dwc->lock, flags);
 	return 0;
 }

drivers/usb/dwc3/ep0.c

@@ -236,6 +236,8 @@ int dwc3_gadget_ep0_queue(struct usb_ep *ep, struct usb_request *request,
 	unsigned long			flags;
 
 	int				ret;
+	enum dwc3_link_state		link_state;
+	u32				reg;
 
 	spin_lock_irqsave(&dwc->lock, flags);
 	if (!dep->endpoint.desc) {
@@ -252,6 +254,18 @@ int dwc3_gadget_ep0_queue(struct usb_ep *ep, struct usb_request *request,
 		goto out;
 	}
 
+	/* if link stats is in L1 initiate  remote wakeup before queuing req */
+	if (dwc->speed != DWC3_DSTS_SUPERSPEED) {
+		link_state = dwc3_get_link_state(dwc);
+		/* in HS this link state is same as L1 */
+		if (link_state == DWC3_LINK_STATE_U2) {
+			dwc->l1_remote_wakeup_cnt++;
+			reg = dwc3_readl(dwc->regs, DWC3_DCTL);
+			reg |= DWC3_DCTL_ULSTCHNG_RECOVERY;
+			dwc3_writel(dwc->regs, DWC3_DCTL, reg);
+		}
+	}
+
 	dwc3_trace(trace_dwc3_ep0,
 			"queueing request %pK to %s length %d state '%s'",
 			request, dep->name, request->length,

drivers/usb/dwc3/gadget.c

@@ -1317,13 +1317,6 @@ static int dwc3_gadget_wakeup(struct usb_gadget *g)
 	return 0;
 }
 
-static inline enum dwc3_link_state dwc3_get_link_state(struct dwc3 *dwc)
-{
-	u32 reg;
-	reg = dwc3_readl(dwc->regs, DWC3_DSTS);
-	return DWC3_DSTS_USBLNKST(reg);
-}
-
 static bool dwc3_gadget_is_suspended(struct dwc3 *dwc)
 {
 	if (atomic_read(&dwc->in_lpm) ||

drivers/usb/dwc3/gadget.h

@@ -84,6 +84,14 @@ static inline void dwc3_gadget_move_request_queued(struct dwc3_request *req)
 	list_move_tail(&req->list, &dep->req_queued);
 }
 
+static inline enum dwc3_link_state dwc3_get_link_state(struct dwc3 *dwc)
+{
+	u32 reg;
+
+	reg = dwc3_readl(dwc->regs, DWC3_DSTS);
+	return DWC3_DSTS_USBLNKST(reg);
+}
+
 void dwc3_gadget_giveback(struct dwc3_ep *dep, struct dwc3_request *req,
 		int status);