usb: dwc3: gadget: Refactor pullup()

Move soft-disconnect sequence out of dwc3_gadget_pullup(). No
functional change here.
Signed-off-by: Thinh Nguyen <Thinh.Nguyen@synopsys.com>
Link: https://lore.kernel.org/r/4c0f259b17d95acaaa931f90276683a48a32fe22.1650593829.git.Thinh.Nguyen@synopsys.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/dwc3/gadget.c

@@ -2507,6 +2507,40 @@ static void dwc3_gadget_disable_irq(struct dwc3 *dwc);
 static void __dwc3_gadget_stop(struct dwc3 *dwc);
 static int __dwc3_gadget_start(struct dwc3 *dwc);
 
+static int dwc3_gadget_soft_disconnect(struct dwc3 *dwc)
+{
+	u32 count;
+
+	dwc->connected = false;
+
+	/*
+	 * In the Synopsys DesignWare Cores USB3 Databook Rev. 3.30a
+	 * Section 4.1.8 Table 4-7, it states that for a device-initiated
+	 * disconnect, the SW needs to ensure that it sends "a DEPENDXFER
+	 * command for any active transfers" before clearing the RunStop
+	 * bit.
+	 */
+	dwc3_stop_active_transfers(dwc);
+	__dwc3_gadget_stop(dwc);
+
+	/*
+	 * In the Synopsys DesignWare Cores USB3 Databook Rev. 3.30a
+	 * Section 1.3.4, it mentions that for the DEVCTRLHLT bit, the
+	 * "software needs to acknowledge the events that are generated
+	 * (by writing to GEVNTCOUNTn) while it is waiting for this bit
+	 * to be set to '1'."
+	 */
+	count = dwc3_readl(dwc->regs, DWC3_GEVNTCOUNT(0));
+	count &= DWC3_GEVNTCOUNT_MASK;
+	if (count > 0) {
+		dwc3_writel(dwc->regs, DWC3_GEVNTCOUNT(0), count);
+		dwc->ev_buf->lpos = (dwc->ev_buf->lpos + count) %
+			dwc->ev_buf->length;
+	}
+
+	return dwc3_gadget_run_stop(dwc, false, false);
+}
+
 static int dwc3_gadget_pullup(struct usb_gadget *g, int is_on)
 {
 	struct dwc3		*dwc = gadget_to_dwc(g);
@@ -2563,33 +2597,7 @@ static int dwc3_gadget_pullup(struct usb_gadget *g, int is_on)
 	spin_lock_irqsave(&dwc->lock, flags);
 
 	if (!is_on) {
-		u32 count;
-
-		dwc->connected = false;
-		/*
-		 * In the Synopsis DesignWare Cores USB3 Databook Rev. 3.30a
-		 * Section 4.1.8 Table 4-7, it states that for a device-initiated
-		 * disconnect, the SW needs to ensure that it sends "a DEPENDXFER
-		 * command for any active transfers" before clearing the RunStop
-		 * bit.
-		 */
-		dwc3_stop_active_transfers(dwc);
-		__dwc3_gadget_stop(dwc);
-
-		/*
-		 * In the Synopsis DesignWare Cores USB3 Databook Rev. 3.30a
-		 * Section 1.3.4, it mentions that for the DEVCTRLHLT bit, the
-		 * "software needs to acknowledge the events that are generated
-		 * (by writing to GEVNTCOUNTn) while it is waiting for this bit
-		 * to be set to '1'."
-		 */
-		count = dwc3_readl(dwc->regs, DWC3_GEVNTCOUNT(0));
-		count &= DWC3_GEVNTCOUNT_MASK;
-		if (count > 0) {
-			dwc3_writel(dwc->regs, DWC3_GEVNTCOUNT(0), count);
-			dwc->ev_buf->lpos = (dwc->ev_buf->lpos + count) %
-						dwc->ev_buf->length;
-		}
+		ret = dwc3_gadget_soft_disconnect(dwc);
 	} else {
 		/*
 		 * In the Synopsys DWC_usb31 1.90a programming guide section
@@ -2603,9 +2611,8 @@ static int dwc3_gadget_pullup(struct usb_gadget *g, int is_on)
 
 		dwc3_event_buffers_setup(dwc);
 		__dwc3_gadget_start(dwc);
+		ret = dwc3_gadget_run_stop(dwc, true, false);
 	}
-
-	ret = dwc3_gadget_run_stop(dwc, is_on, false);
 	spin_unlock_irqrestore(&dwc->lock, flags);
 	enable_irq(dwc->irq_gadget);