usb: gadget: f_rndis: add configfs support

f_rndis learns about configfs so we can, eventually,
remove in-kernel gadget drivers.

Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

1 files changed, 9 insertions, 0 deletions

diff --git a/drivers/usb/gadget/u_rndis.h b/drivers/usb/gadget/u_rndis.h
index d274df56ce75..c62ba82e9600 100644
--- a/drivers/usb/gadget/u_rndis.h
+++ b/drivers/usb/gadget/u_rndis.h
@@ -25,6 +25,15 @@ struct f_rndis_opts {
         struct net_device               *net;
         bool                            bound;
         bool                            borrowed_net;
+
+        /*
+         * Read/write access to configfs attributes is handled by configfs.
+         *
+         * This is to protect the data from concurrent access by read/write
+         * and create symlink/remove symlink.
+         */
+        struct mutex                    lock;
+        int                             refcnt;
 };
 
 void rndis_borrow_net(struct usb_function_instance *f, struct net_device *net);