Merge tag 'usb-for-v4.13' of git://git.kernel.org/pub/scm/linux/kernel/git/balbi/usb into usb-testing

Felipe writes:

usb: changes for v4.13 merge window

This time around we have a total of 57 non-merge commits. A list of
most important changes follows:

- Improvements to dwc3 tracing interface
- Initial dual-role support for dwc3
- Improvements to how we handle DMA resources in dwc3
- A new f_uac1 implementation which much more flexible
- Removal of AVR32 bits
- Improvements to f_mass_storage driver

1 files changed, 34 insertions, 3 deletions

diff --git a/drivers/usb/gadget/udc/core.c b/drivers/usb/gadget/udc/core.c
index a03aec574f64..e6f04eee95c4 100644
--- a/drivers/usb/gadget/udc/core.c
+++ b/drivers/usb/gadget/udc/core.c
@@ -140,10 +140,8 @@ int usb_ep_disable(struct usb_ep *ep)
 		goto out;
 
 	ret = ep->ops->disable(ep);
-	if (ret) {
-		ret = ret;
+	if (ret)
 		goto out;
-	}
 
 	ep->enabled = false;
 
@@ -1067,6 +1065,23 @@ static inline void usb_gadget_udc_stop(struct usb_udc *udc)
 }
 
 /**
+ * usb_gadget_udc_set_speed - tells usb device controller speed supported by
+ *    current driver
+ * @udc: The device we want to set maximum speed
+ * @speed: The maximum speed to allowed to run
+ *
+ * This call is issued by the UDC Class driver before calling
+ * usb_gadget_udc_start() in order to make sure that we don't try to
+ * connect on speeds the gadget driver doesn't support.
+ */
+static inline void usb_gadget_udc_set_speed(struct usb_udc *udc,
+					    enum usb_device_speed speed)
+{
+	if (udc->gadget->ops->udc_set_speed)
+		udc->gadget->ops->udc_set_speed(udc->gadget, speed);
+}
+
+/**
  * usb_udc_release - release the usb_udc struct
  * @dev: the dev member within usb_udc
  *
@@ -1299,6 +1314,9 @@ static int udc_bind_to_driver(struct usb_udc *udc, struct usb_gadget_driver *dri
 	udc->dev.driver = &driver->driver;
 	udc->gadget->dev.driver = &driver->driver;
 
+	if (driver->max_speed < udc->gadget->max_speed)
+		usb_gadget_udc_set_speed(udc, driver->max_speed);
+
 	ret = driver->bind(udc->gadget, driver);
 	if (ret)
 		goto err1;
@@ -1451,6 +1469,18 @@ static ssize_t state_show(struct device *dev, struct device_attribute *attr,
 }
 static DEVICE_ATTR_RO(state);
 
+static ssize_t function_show(struct device *dev, struct device_attribute *attr,
+			     char *buf)
+{
+	struct usb_udc		*udc = container_of(dev, struct usb_udc, dev);
+	struct usb_gadget_driver *drv = udc->driver;
+
+	if (!drv || !drv->function)
+		return 0;
+	return scnprintf(buf, PAGE_SIZE, "%s\n", drv->function);
+}
+static DEVICE_ATTR_RO(function);
+
 #define USB_UDC_SPEED_ATTR(name, param)					\
 ssize_t name##_show(struct device *dev,					\
 		struct device_attribute *attr, char *buf)		\
@@ -1486,6 +1516,7 @@ static struct attribute *usb_udc_attrs[] = {
 	&dev_attr_srp.attr,
 	&dev_attr_soft_connect.attr,
 	&dev_attr_state.attr,
+	&dev_attr_function.attr,
 	&dev_attr_current_speed.attr,
 	&dev_attr_maximum_speed.attr,