Merge branch 'usb-midi-fix-3.7' of git://git.alsa-project.org/alsa-kprivate into...

Merge a regression fix for USB MIDI on non-standard usb-audio drivers
by Clemens.

diff --git a/sound/usb/midi.c b/sound/usb/midi.c
index c83f6143c0eb34d8f77f969e1928427458b4268a..eeefbce3873c11dc35a6e174c4ace79daeeaa8c1 100644 (file)
--- a/sound/usb/midi.c
+++ b/sound/usb/midi.c
@@ -148,6 +148,7 @@ struct snd_usb_midi_out_endpoint {
                struct snd_usb_midi_out_endpoint* ep;
                struct snd_rawmidi_substream *substream;
                int active;
+               bool autopm_reference;
                uint8_t cable;          /* cable number << 4 */
                uint8_t state;
 #define STATE_UNKNOWN  0
@@ -1076,7 +1077,8 @@ static int snd_usbmidi_output_open(struct snd_rawmidi_substream *substream)
                return -ENXIO;
        }
        err = usb_autopm_get_interface(umidi->iface);
-       if (err < 0)
+       port->autopm_reference = err >= 0;
+       if (err < 0 && err != -EACCES)
                return -EIO;
        substream->runtime->private_data = port;
        port->state = STATE_UNKNOWN;
@@ -1087,9 +1089,11 @@ static int snd_usbmidi_output_open(struct snd_rawmidi_substream *substream)
 static int snd_usbmidi_output_close(struct snd_rawmidi_substream *substream)
 {
        struct snd_usb_midi* umidi = substream->rmidi->private_data;
+       struct usbmidi_out_port *port = substream->runtime->private_data;
 
        substream_open(substream, 0);
-       usb_autopm_put_interface(umidi->iface);
+       if (port->autopm_reference)
+               usb_autopm_put_interface(umidi->iface);
        return 0;
 }