usb: gadget: f_rndis: fix interface id for OS descriptors

f->os_desc_table[0].if_id is zero by default. If the actual id happens
to be different then no Feature Descriptors will be returned to the host
for this interface, so assign if_id as soon as it is known.

Cc: <stable@vger.kernel.org> # v3.16
Acked-by: Michal Nazarewicz <mina86@mina86.com>
Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

1 files changed, 4 insertions, 0 deletions

diff --git a/drivers/usb/gadget/function/f_rndis.c b/drivers/usb/gadget/function/f_rndis.c
index eed3ad878047..a7b6bbbd697d 100644
--- a/drivers/usb/gadget/function/f_rndis.c
+++ b/drivers/usb/gadget/function/f_rndis.c
@@ -727,6 +727,10 @@ rndis_bind(struct usb_configuration *c, struct usb_function *f)
         rndis_control_intf.bInterfaceNumber = status;
         rndis_union_desc.bMasterInterface0 = status;
 
+        if (cdev->use_os_string)
+                f->os_desc_table[0].if_id =
+                        rndis_iad_descriptor.bFirstInterface;
+
         status = usb_interface_id(c, f);
         if (status < 0)
                 goto fail;