xhci: dbc: Don't shadow error codes in store() functions

kstrtox() along with regmap API can return different error codes
based on the circumstances. Don't shadow them when returning to
the caller.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20231201150647.1307406-7-mathias.nyman@linux.intel.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/host/xhci-dbgcap.c

@@ -977,9 +977,11 @@ static ssize_t dbc_idVendor_store(struct device *dev,
 	void __iomem		*ptr;
 	u16			value;
 	u32			dev_info;
+	int ret;
 
-	if (kstrtou16(buf, 0, &value))
-		return -EINVAL;
+	ret = kstrtou16(buf, 0, &value);
+	if (ret)
+		return ret;
 
 	xhci = hcd_to_xhci(dev_get_drvdata(dev));
 	dbc = xhci->dbc;
@@ -1017,9 +1019,11 @@ static ssize_t dbc_idProduct_store(struct device *dev,
 	void __iomem		*ptr;
 	u32			dev_info;
 	u16			value;
+	int ret;
 
-	if (kstrtou16(buf, 0, &value))
-		return -EINVAL;
+	ret = kstrtou16(buf, 0, &value);
+	if (ret)
+		return ret;
 
 	xhci = hcd_to_xhci(dev_get_drvdata(dev));
 	dbc = xhci->dbc;
@@ -1056,9 +1060,11 @@ static ssize_t dbc_bcdDevice_store(struct device *dev,
 	void __iomem *ptr;
 	u32 dev_info;
 	u16 value;
+	int ret;
 
-	if (kstrtou16(buf, 0, &value))
-		return -EINVAL;
+	ret = kstrtou16(buf, 0, &value);
+	if (ret)
+		return ret;
 
 	xhci = hcd_to_xhci(dev_get_drvdata(dev));
 	dbc = xhci->dbc;
@@ -1098,9 +1104,13 @@ static ssize_t dbc_bInterfaceProtocol_store(struct device *dev,
 	u8 value;
 	int ret;
 
-	/* bInterfaceProtocol is 8 bit, but xhci only supports values 0 and 1 */
+	/* bInterfaceProtocol is 8 bit, but... */
 	ret = kstrtou8(buf, 0, &value);
-	if (ret || value > 1)
+	if (ret)
+		return ret;
+
+	/* ...xhci only supports values 0 and 1 */
+	if (value > 1)
 		return -EINVAL;
 
 	xhci = hcd_to_xhci(dev_get_drvdata(dev));