[RFC/PATCH 01/32] usb: gadget: udc-core: allow udc class register gadget device

Currently all UDC drivers are calling
device_register() before calling
usb_add_gadget_udc(). In order to avoid
code duplication, we can allow udc-core.c
register that device.

However that would become a really large patch,
so to cope with the meanwhile and allow us
to write bite-sized patches, we're adding
a flag which will be set by UDC driver once
it removes the code for registering the
gadget device.

Once all are converted, the new flag will
be removed.

Signed-off-by: Felipe Balbi <redacted>
---
 drivers/usb/gadget/udc-core.c | 23 +++++++++++++++++++----
 include/linux/usb/gadget.h    |  4 ++++
 2 files changed, 23 insertions(+), 4 deletions(-)

diff --git a/drivers/usb/gadget/udc-core.c

b/drivers/usb/gadget/udc-core.c index 2a9cd36..9195054 100644

--- a/drivers/usb/gadget/udc-core.c
+++ b/drivers/usb/gadget/udc-core.c

@@ -173,6 +173,14 @@ int usb_add_gadget_udc(struct device *parent,

struct usb_gadget *gadget) if (!udc)
 		goto err1;

+	if (gadget->register_my_device) {
+		dev_set_name(&gadget->dev, "gadget");
+
+		ret = device_register(&gadget->dev);
+		if (ret)
+			goto err2;
+	}
+
 	device_initialize(&udc->dev);
 	udc->dev.release = usb_udc_release;
 	udc->dev.class = udc_class;

@@ -180,7 +188,7 @@ int usb_add_gadget_udc(struct device *parent, struct

usb_gadget *gadget) udc->dev.parent = parent;
 	ret = dev_set_name(&udc->dev, "%s", kobject_name(&parent->kobj));
 	if (ret)
-		goto err2;
+		goto err3;

 	udc->gadget = gadget;

@@ -189,18 +197,22 @@ int usb_add_gadget_udc(struct device *parent,

struct usb_gadget *gadget)

 	ret = device_add(&udc->dev);
 	if (ret)
-		goto err3;
+		goto err4;

 	mutex_unlock(&udc_lock);

 	return 0;
-err3:
+
+err4:
 	list_del(&udc->list);
 	mutex_unlock(&udc_lock);

-err2:
+err3:
 	put_device(&udc->dev);

+err2:
+	if (gadget->register_my_device)
+		put_device(&gadget->dev);
 err1:
 	return ret;
 }

@@ -254,6 +266,9 @@ found:

 	kobject_uevent(&udc->dev.kobj, KOBJ_REMOVE);
 	device_unregister(&udc->dev);
+
+	if (gadget->register_my_device)
+		device_unregister(&gadget->dev);
 }
 EXPORT_SYMBOL_GPL(usb_del_gadget_udc);

diff --git a/include/linux/usb/gadget.h b/include/linux/usb/gadget.h
index 2e297e8..fcd9ef8 100644
--- a/include/linux/usb/gadget.h
+++ b/include/linux/usb/gadget.h

@@ -494,6 +494,9 @@ struct usb_gadget_ops {
  *	only supports HNP on a different root port.
  * @b_hnp_enable: OTG device feature flag, indicating that the A-Host
  *	enabled HNP support.
+ * @register_my_device: Flag telling udc-core that UDC driver didn't
+ *	register the gadget device to the driver model. Temporary until
+ *	all UDC drivers are fixed up properly.
  * @name: Identifies the controller hardware type.  Used in diagnostics

*	and sometimes configuration.
  * @dev: Driver model state for this abstract device.

@@ -531,6 +534,7 @@ struct usb_gadget {
 	unsigned			b_hnp_enable:1;
 	unsigned			a_hnp_support:1;
 	unsigned			a_alt_hnp_support:1;
+	unsigned			register_my_device:1;
 	const char			*name;
 	struct device			dev;
 	unsigned			out_epnum;