usb: gadget: function: f_obex: fix Interface Descriptor Test

On USB20CV's Interface Descriptor Test, a series
of SetInterface/GetInterface requests are issued
and gadget driver is required to always return
correct alternate setting.

In one step of the test, g_serial with f_obex
was returning the wrong value (1 instead of 0).

In order to fix this, we will now hold currently
selected alternate setting inside our struct f_obex
and just return that from our ->get_alt()
implementation.

Note that his also simplifies the code a bit.

Signed-off-by: Felipe Balbi <balbi@ti.com>

diff --git a/drivers/usb/gadget/function/f_obex.c b/drivers/usb/gadget/function/f_obex.c
index 5f40080..1a1a490 100644 (file)
--- a/drivers/usb/gadget/function/f_obex.c
+++ b/drivers/usb/gadget/function/f_obex.c
@@ -35,6 +35,7 @@ struct f_obex {
        struct gserial                  port;
        u8                              ctrl_id;
        u8                              data_id;
+       u8                              cur_alt;
        u8                              port_num;
        u8                              can_activate;
 };
@@ -235,6 +236,8 @@ static int obex_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
        } else
                goto fail;
 
+       obex->cur_alt = alt;
+
        return 0;
 
 fail:
@@ -245,10 +248,7 @@ static int obex_get_alt(struct usb_function *f, unsigned intf)
 {
        struct f_obex           *obex = func_to_obex(f);
 
-       if (intf == obex->ctrl_id)
-               return 0;
-
-       return obex->port.in->driver_data ? 1 : 0;
+       return obex->cur_alt;
 }
 
 static void obex_disable(struct usb_function *f)