usb: gadget: f_midi: set altsettings only for MIDIStreaming interface

This avoids duplication of USB requests for OUT endpoint and
re-enabling endpoints.

Signed-off-by: Felipe F. Tonello <eu@felipetonello.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

diff --git a/drivers/usb/gadget/function/f_midi.c b/drivers/usb/gadget/function/f_midi.c
index 29bfca1..e804231 100644 (file)
--- a/drivers/usb/gadget/function/f_midi.c
+++ b/drivers/usb/gadget/function/f_midi.c
@@ -75,6 +75,7 @@ struct f_midi {
        struct usb_ep           *in_ep, *out_ep;
        struct snd_card         *card;
        struct snd_rawmidi      *rmidi;
+       u8                      ms_id;
 
        struct snd_rawmidi_substream *in_substream[MAX_PORTS];
        struct snd_rawmidi_substream *out_substream[MAX_PORTS];
@@ -321,8 +322,8 @@ static int f_midi_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
        unsigned i;
        int err;
 
-       /* For Control Device interface we do nothing */
-       if (intf == 0)
+       /* we only set alt for MIDIStreaming interface */
+       if (intf != midi->ms_id)
                return 0;
 
        err = f_midi_start_ep(midi, f, midi->in_ep);
@@ -730,6 +731,7 @@ static int f_midi_bind(struct usb_configuration *c, struct usb_function *f)
                goto fail;
        ms_interface_desc.bInterfaceNumber = status;
        ac_header_desc.baInterfaceNr[0] = status;
+       midi->ms_id = status;
 
        status = -ENODEV;