USB: at91: at91-ohci: fix set/get power

in commit aa6e52a35 we introduce the support of overcurrent notification
but the set and get of the power without checking if the gpio is valid or not

Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Acked-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/usb/host/ohci-at91.c

@@ -223,6 +223,9 @@ static void ohci_at91_usb_set_power(struct at91_usbh_data *pdata, int port, int
 	if (port < 0 || port >= 2)
 		return;
 
+	if (pdata->vbus_pin[port] <= 0)
+		return;
+
 	gpio_set_value(pdata->vbus_pin[port], !pdata->vbus_pin_inverted ^ enable);
 }
 
@@ -231,6 +234,9 @@ static int ohci_at91_usb_get_power(struct at91_usbh_data *pdata, int port)
 	if (port < 0 || port >= 2)
 		return -EINVAL;
 
+	if (pdata->vbus_pin[port] <= 0)
+		return -EINVAL;
+
 	return gpio_get_value(pdata->vbus_pin[port]) ^ !pdata->vbus_pin_inverted;
 }