usb: dwc3: core: move the core check before soft reset

We read the DWC3_GSNPSID register to make sure we got the correct
register offset passed. One of the recent commits moved the soft reset
before this so in case of the wrong offset we end up with "reset timed
out". This patch moves the "id" check before the reset again.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Felipe Balbi <balbi@ti.com>

drivers/usb/dwc3/core.c

@@ -241,6 +241,15 @@ static int __devinit dwc3_core_init(struct dwc3 *dwc)
 	u32			reg;
 	int			ret;
 
+	reg = dwc3_readl(dwc->regs, DWC3_GSNPSID);
+	/* This should read as U3 followed by revision number */
+	if ((reg & DWC3_GSNPSID_MASK) != 0x55330000) {
+		dev_err(dwc->dev, "this is not a DesignWare USB3 DRD Core\n");
+		ret = -ENODEV;
+		goto err0;
+	}
+	dwc->revision = reg & DWC3_GSNPSREV_MASK;
+
 	dwc3_core_soft_reset(dwc);
 
 	/* issue device SoftReset too */
@@ -260,16 +269,6 @@ static int __devinit dwc3_core_init(struct dwc3 *dwc)
 		cpu_relax();
 	} while (true);
 
-	reg = dwc3_readl(dwc->regs, DWC3_GSNPSID);
-	/* This should read as U3 followed by revision number */
-	if ((reg & DWC3_GSNPSID_MASK) != 0x55330000) {
-		dev_err(dwc->dev, "this is not a DesignWare USB3 DRD Core\n");
-		ret = -ENODEV;
-		goto err0;
-	}
-
-	dwc->revision = reg & DWC3_GSNPSREV_MASK;
-
 	ret = dwc3_alloc_event_buffers(dwc, DWC3_EVENT_BUFFERS_NUM,
 			DWC3_EVENT_BUFFERS_SIZE);
 	if (ret) {