ALSA: caiaq - Fix Oops with MIDI

The snd-usb-caiaq driver causes Oops occasionally when accessing MIDI
devices.  This patch fixes the Oops and invalid URB submission errors
as well.

Cc: stable@kernel.org
Signed-off-by: Takashi Iwai <tiwai@suse.de>

diff --git a/sound/usb/caiaq/caiaq-device.h b/sound/usb/caiaq/caiaq-device.h
index f9fbdbae269d21491d2dc84f726cfc12cdf51261..ab56e738c5fc021f71af01365c5f164f64779cb2 100644 (file)
--- a/sound/usb/caiaq/caiaq-device.h
+++ b/sound/usb/caiaq/caiaq-device.h
@@ -75,6 +75,7 @@ struct snd_usb_caiaqdev {
        wait_queue_head_t ep1_wait_queue;
        wait_queue_head_t prepare_wait_queue;
        int spec_received, audio_parm_answer;
+       int midi_out_active;
 
        char vendor_name[CAIAQ_USB_STR_LEN];
        char product_name[CAIAQ_USB_STR_LEN];

diff --git a/sound/usb/caiaq/caiaq-midi.c b/sound/usb/caiaq/caiaq-midi.c
index 30b57f97c6e411221517f9a8c3d0a5e1a42036b0..f19fd360c9367b76fdb4df440743fea019dc7d77 100644 (file)
--- a/sound/usb/caiaq/caiaq-midi.c
+++ b/sound/usb/caiaq/caiaq-midi.c
@@ -59,6 +59,11 @@ static int snd_usb_caiaq_midi_output_open(struct snd_rawmidi_substream *substrea
 
 static int snd_usb_caiaq_midi_output_close(struct snd_rawmidi_substream *substream)
 {
+       struct snd_usb_caiaqdev *dev = substream->rmidi->private_data;
+       if (dev->midi_out_active) {
+               usb_kill_urb(&dev->midi_out_urb);
+               dev->midi_out_active = 0;
+       }
        return 0;
 }
 
@@ -69,7 +74,8 @@ static void snd_usb_caiaq_midi_send(struct snd_usb_caiaqdev *dev,
        
        dev->midi_out_buf[0] = EP1_CMD_MIDI_WRITE;
        dev->midi_out_buf[1] = 0; /* port */
-       len = snd_rawmidi_transmit_peek(substream, dev->midi_out_buf+3, EP1_BUFSIZE-3);
+       len = snd_rawmidi_transmit(substream, dev->midi_out_buf + 3,
+                                  EP1_BUFSIZE - 3);
        
        if (len <= 0)
                return;
@@ -79,24 +85,24 @@ static void snd_usb_caiaq_midi_send(struct snd_usb_caiaqdev *dev,
        
        ret = usb_submit_urb(&dev->midi_out_urb, GFP_ATOMIC);
        if (ret < 0)
-               log("snd_usb_caiaq_midi_send(%p): usb_submit_urb() failed, %d\n",
-                               substream, ret);
+               log("snd_usb_caiaq_midi_send(%p): usb_submit_urb() failed,"
+                   "ret=%d, len=%d\n",
+                   substream, ret, len);
+       else
+               dev->midi_out_active = 1;
 }
 
 static void snd_usb_caiaq_midi_output_trigger(struct snd_rawmidi_substream *substream, int up)
 {
        struct snd_usb_caiaqdev *dev = substream->rmidi->private_data;
        
-       if (dev->midi_out_substream != NULL)
-               return;
-       
-       if (!up) {
+       if (up) {
+               dev->midi_out_substream = substream;
+               if (!dev->midi_out_active)
+                       snd_usb_caiaq_midi_send(dev, substream);
+       } else {
                dev->midi_out_substream = NULL;
-               return;
        }
-       
-       dev->midi_out_substream = substream;
-       snd_usb_caiaq_midi_send(dev, substream);
 }
 
 
@@ -161,16 +167,14 @@ int snd_usb_caiaq_midi_init(struct snd_usb_caiaqdev *device)
 void snd_usb_caiaq_midi_output_done(struct urb* urb)
 {
        struct snd_usb_caiaqdev *dev = urb->context;
-       char *buf = urb->transfer_buffer;
        
+       dev->midi_out_active = 0;
        if (urb->status != 0)
                return;
 
        if (!dev->midi_out_substream)
                return;
 
-       snd_rawmidi_transmit_ack(dev->midi_out_substream, buf[2]);
-       dev->midi_out_substream = NULL;
        snd_usb_caiaq_midi_send(dev, dev->midi_out_substream);
 }