usb: gadget: udc-core: introduce usb_add_gadget_udc_release()
not all UDC drivers need a proper release function,
for those which don't need it, we udc-core will provide
a no-op release method so we can remove "redefinition"
of such methods in almost every UDC driver.
Signed-off-by: Felipe Balbi <balbi@ti.com>
diff --git a/drivers/usb/gadget/udc-core.c b/drivers/usb/gadget/udc-core.c
index 2423d02..a50811e 100644
--- a/drivers/usb/gadget/udc-core.c
+++ b/drivers/usb/gadget/udc-core.c
@@ -166,15 +166,23 @@
}
static const struct attribute_group *usb_udc_attr_groups[];
+
+static void usb_udc_nop_release(struct device *dev)
+{
+ dev_vdbg(dev, "%s\n", __func__);
+}
+
/**
- * usb_add_gadget_udc - adds a new gadget to the udc class driver list
- * @parent: the parent device to this udc. Usually the controller
- * driver's device.
- * @gadget: the gadget to be added to the list
+ * usb_add_gadget_udc_release - adds a new gadget to the udc class driver list
+ * @parent: the parent device to this udc. Usually the controller driver's
+ * device.
+ * @gadget: the gadget to be added to the list.
+ * @release: a gadget release function.
*
* Returns zero on success, negative errno otherwise.
*/
-int usb_add_gadget_udc(struct device *parent, struct usb_gadget *gadget)
+int usb_add_gadget_udc_release(struct device *parent, struct usb_gadget *gadget,
+ void (*release)(struct device *dev))
{
struct usb_udc *udc;
int ret = -ENOMEM;
@@ -190,6 +198,13 @@
gadget->dev.dma_parms = parent->dma_parms;
gadget->dev.dma_mask = parent->dma_mask;
+ if (release) {
+ gadget->dev.release = release;
+ } else {
+ if (!gadget->dev.release)
+ gadget->dev.release = usb_udc_nop_release;
+ }
+
ret = device_register(&gadget->dev);
if (ret)
goto err2;
@@ -231,6 +246,20 @@
err1:
return ret;
}
+EXPORT_SYMBOL_GPL(usb_add_gadget_udc_release);
+
+/**
+ * usb_add_gadget_udc - adds a new gadget to the udc class driver list
+ * @parent: the parent device to this udc. Usually the controller
+ * driver's device.
+ * @gadget: the gadget to be added to the list
+ *
+ * Returns zero on success, negative errno otherwise.
+ */
+int usb_add_gadget_udc(struct device *parent, struct usb_gadget *gadget)
+{
+ return usb_add_gadget_udc_release(parent, gadget, NULL);
+}
EXPORT_SYMBOL_GPL(usb_add_gadget_udc);
static void usb_gadget_remove_driver(struct usb_udc *udc)
diff --git a/include/linux/usb/gadget.h b/include/linux/usb/gadget.h
index 32b734d..c454a88 100644
--- a/include/linux/usb/gadget.h
+++ b/include/linux/usb/gadget.h
@@ -874,6 +874,8 @@
*/
int usb_gadget_unregister_driver(struct usb_gadget_driver *driver);
+extern int usb_add_gadget_udc_release(struct device *parent,
+ struct usb_gadget *gadget, void (*release)(struct device *dev));
extern int usb_add_gadget_udc(struct device *parent, struct usb_gadget *gadget);
extern void usb_del_gadget_udc(struct usb_gadget *gadget);
extern int udc_attach_driver(const char *name,