greybus: core: make the control object be a device

Make the control object be a greybus device.

The control device will be used to expose attributes specific to
greybus-type interfaces.

Signed-off-by: Johan Hovold <johan@hovoldconsulting.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

drivers/staging/greybus/control.c

@@ -213,6 +213,20 @@ int gb_control_timesync_authoritative(struct gb_control *control,
 				 NULL, 0);
 }
 
+static void gb_control_release(struct device *dev)
+{
+	struct gb_control *control = to_gb_control(dev);
+
+	gb_connection_destroy(control->connection);
+
+	kfree(control);
+}
+
+struct device_type greybus_control_type = {
+	.name =		"greybus_control",
+	.release =	gb_control_release,
+};
+
 struct gb_control *gb_control_create(struct gb_interface *intf)
 {
 	struct gb_control *control;
@@ -221,6 +235,8 @@ struct gb_control *gb_control_create(struct gb_interface *intf)
 	if (!control)
 		return NULL;
 
+	control->intf = intf;
+
 	control->connection = gb_connection_create_control(intf);
 	if (IS_ERR(control->connection)) {
 		dev_err(&intf->dev,
@@ -230,6 +246,13 @@ struct gb_control *gb_control_create(struct gb_interface *intf)
 		return NULL;
 	}
 
+	control->dev.parent = &intf->dev;
+	control->dev.bus = &greybus_bus_type;
+	control->dev.type = &greybus_control_type;
+	control->dev.dma_mask = intf->dev.dma_mask;
+	device_initialize(&control->dev);
+	dev_set_name(&control->dev, "%s.ctrl", dev_name(&intf->dev));
+
 	gb_connection_set_data(control->connection, control);
 
 	return control;
@@ -271,8 +294,7 @@ void gb_control_disable(struct gb_control *control)
 	gb_connection_disable(control->connection);
 }
 
-void gb_control_destroy(struct gb_control *control)
+void gb_control_put(struct gb_control *control)
 {
-	gb_connection_destroy(control->connection);
-	kfree(control);
+	put_device(&control->dev);
 }

drivers/staging/greybus/control.h

@@ -11,18 +11,22 @@
 #define __CONTROL_H
 
 struct gb_control {
-	struct gb_connection	*connection;
+	struct device dev;
+	struct gb_interface *intf;
+
+	struct gb_connection *connection;
 
 	u8 protocol_major;
 	u8 protocol_minor;
 
 	bool has_bundle_version;
 };
+#define to_gb_control(d) container_of(d, struct gb_control, dev)
 
 struct gb_control *gb_control_create(struct gb_interface *intf);
 int gb_control_enable(struct gb_control *control);
 void gb_control_disable(struct gb_control *control);
-void gb_control_destroy(struct gb_control *control);
+void gb_control_put(struct gb_control *control);
 
 int gb_control_get_bundle_versions(struct gb_control *control);
 int gb_control_connected_operation(struct gb_control *control, u16 cport_id);

drivers/staging/greybus/core.c

@@ -86,6 +86,7 @@ static int greybus_uevent(struct device *dev, struct kobj_uevent_env *env)
 {
 	struct gb_host_device *hd;
 	struct gb_interface *intf = NULL;
+	struct gb_control *control = NULL;
 	struct gb_bundle *bundle = NULL;
 	struct gb_svc *svc = NULL;
 
@@ -94,6 +95,10 @@ static int greybus_uevent(struct device *dev, struct kobj_uevent_env *env)
 	} else if (is_gb_interface(dev)) {
 		intf = to_gb_interface(dev);
 		hd = intf->hd;
+	} else if (is_gb_control(dev)) {
+		control = to_gb_control(dev);
+		intf = control->intf;
+		hd = intf->hd;
 	} else if (is_gb_bundle(dev)) {
 		bundle = to_gb_bundle(dev);
 		intf = bundle->intf;

drivers/staging/greybus/greybus.h

@@ -113,6 +113,7 @@ extern struct bus_type greybus_bus_type;
 
 extern struct device_type greybus_hd_type;
 extern struct device_type greybus_interface_type;
+extern struct device_type greybus_control_type;
 extern struct device_type greybus_bundle_type;
 extern struct device_type greybus_svc_type;
 
@@ -126,6 +127,11 @@ static inline int is_gb_interface(const struct device *dev)
 	return dev->type == &greybus_interface_type;
 }
 
+static inline int is_gb_control(const struct device *dev)
+{
+	return dev->type == &greybus_control_type;
+}
+
 static inline int is_gb_bundle(const struct device *dev)
 {
 	return dev->type == &greybus_bundle_type;

drivers/staging/greybus/interface.c

@@ -360,7 +360,7 @@ static void gb_interface_release(struct device *dev)
 	kfree(intf->vendor_string);
 
 	if (intf->control)
-		gb_control_destroy(intf->control);
+		gb_control_put(intf->control);
 
 	kfree(intf);
 }