1 files changed, 194 insertions, 96 deletions

diff --git a/sound/usb/usbmidi.c b/sound/usb/usbmidi.c
index 2fb35cc22a3..0eff19ceb7e 100644
--- a/sound/usb/usbmidi.c
+++ b/sound/usb/usbmidi.c
@@ -45,6 +45,7 @@
 #include <linux/slab.h>
 #include <linux/timer.h>
 #include <linux/usb.h>
+#include <linux/wait.h>
 #include <sound/core.h>
 #include <sound/rawmidi.h>
 #include <sound/asequencer.h>
@@ -62,6 +63,9 @@
  */
 #define ERROR_DELAY_JIFFIES (HZ / 10)
 
+#define OUTPUT_URBS 7
+#define INPUT_URBS 7
+
 
 MODULE_AUTHOR("Clemens Ladisch <clemens@ladisch.de>");
 MODULE_DESCRIPTION("USB Audio/MIDI helper module");
@@ -90,7 +94,7 @@ struct snd_usb_midi_endpoint;
 
 struct usb_protocol_ops {
         void (*input)(struct snd_usb_midi_in_endpoint*, uint8_t*, int);
-        void (*output)(struct snd_usb_midi_out_endpoint*);
+        void (*output)(struct snd_usb_midi_out_endpoint *ep, struct urb *urb);
         void (*output_packet)(struct urb*, uint8_t, uint8_t, uint8_t, uint8_t);
         void (*init_out_endpoint)(struct snd_usb_midi_out_endpoint*);
         void (*finish_out_endpoint)(struct snd_usb_midi_out_endpoint*);
@@ -116,11 +120,15 @@ struct snd_usb_midi {
 
 struct snd_usb_midi_out_endpoint {
         struct snd_usb_midi* umidi;
-        struct urb* urb;
-        int urb_active;
+        struct out_urb_context {
+                struct urb *urb;
+                struct snd_usb_midi_out_endpoint *ep;
+        } urbs[OUTPUT_URBS];
+        unsigned int active_urbs;
+        unsigned int drain_urbs;
         int max_transfer;               /* size of urb buffer */
         struct tasklet_struct tasklet;
-
+        unsigned int next_urb;
         spinlock_t buffer_lock;
 
         struct usbmidi_out_port {
@@ -139,11 +147,13 @@ struct snd_usb_midi_out_endpoint {
                 uint8_t data[2];
         } ports[0x10];
         int current_port;
+
+        wait_queue_head_t drain_wait;
 };
 
 struct snd_usb_midi_in_endpoint {
         struct snd_usb_midi* umidi;
-        struct urb* urb;
+        struct urb* urbs[INPUT_URBS];
         struct usbmidi_in_port {
                 struct snd_rawmidi_substream *substream;
                 u8 running_status_length;
@@ -251,10 +261,17 @@ static void snd_usbmidi_in_urb_complete(struct urb* urb)
 
 static void snd_usbmidi_out_urb_complete(struct urb* urb)
 {
-        struct snd_usb_midi_out_endpoint* ep = urb->context;
+        struct out_urb_context *context = urb->context;
+        struct snd_usb_midi_out_endpoint* ep = context->ep;
+        unsigned int urb_index;
 
         spin_lock(&ep->buffer_lock);
-        ep->urb_active = 0;
+        urb_index = context - ep->urbs;
+        ep->active_urbs &= ~(1 << urb_index);
+        if (unlikely(ep->drain_urbs)) {
+                ep->drain_urbs &= ~(1 << urb_index);
+                wake_up(&ep->drain_wait);
+        }
         spin_unlock(&ep->buffer_lock);
         if (urb->status < 0) {
                 int err = snd_usbmidi_urb_error(urb->status);
@@ -274,24 +291,38 @@ static void snd_usbmidi_out_urb_complete(struct urb* urb)
  */
 static void snd_usbmidi_do_output(struct snd_usb_midi_out_endpoint* ep)
 {
-        struct urb* urb = ep->urb;
+        unsigned int urb_index;
+        struct urb* urb;
         unsigned long flags;
 
         spin_lock_irqsave(&ep->buffer_lock, flags);
-        if (ep->urb_active || ep->umidi->chip->shutdown) {
+        if (ep->umidi->chip->shutdown) {
                 spin_unlock_irqrestore(&ep->buffer_lock, flags);
                 return;
         }
 
-        urb->transfer_buffer_length = 0;
-        ep->umidi->usb_protocol_ops->output(ep);
+        urb_index = ep->next_urb;
+        for (;;) {
+                if (!(ep->active_urbs & (1 << urb_index))) {
+                        urb = ep->urbs[urb_index].urb;
+                        urb->transfer_buffer_length = 0;
+                        ep->umidi->usb_protocol_ops->output(ep, urb);
+                        if (urb->transfer_buffer_length == 0)
+                                break;
 
-        if (urb->transfer_buffer_length > 0) {
-                dump_urb("sending", urb->transfer_buffer,
-                         urb->transfer_buffer_length);
-                urb->dev = ep->umidi->chip->dev;
-                ep->urb_active = snd_usbmidi_submit_urb(urb, GFP_ATOMIC) >= 0;
+                        dump_urb("sending", urb->transfer_buffer,
+                                 urb->transfer_buffer_length);
+                        urb->dev = ep->umidi->chip->dev;
+                        if (snd_usbmidi_submit_urb(urb, GFP_ATOMIC) < 0)
+                                break;
+                        ep->active_urbs |= 1 << urb_index;
+                }
+                if (++urb_index >= OUTPUT_URBS)
+                        urb_index = 0;
+                if (urb_index == ep->next_urb)
+                        break;
         }
+        ep->next_urb = urb_index;
         spin_unlock_irqrestore(&ep->buffer_lock, flags);
 }
 
@@ -306,7 +337,7 @@ static void snd_usbmidi_out_tasklet(unsigned long data)
 static void snd_usbmidi_error_timer(unsigned long data)
 {
         struct snd_usb_midi *umidi = (struct snd_usb_midi *)data;
-        int i;
+        unsigned int i, j;
 
         spin_lock(&umidi->disc_lock);
         if (umidi->disconnected) {
@@ -317,8 +348,10 @@ static void snd_usbmidi_error_timer(unsigned long data)
                 struct snd_usb_midi_in_endpoint *in = umidi->endpoints[i].in;
                 if (in && in->error_resubmit) {
                         in->error_resubmit = 0;
-                        in->urb->dev = umidi->chip->dev;
-                        snd_usbmidi_submit_urb(in->urb, GFP_ATOMIC);
+                        for (j = 0; j < INPUT_URBS; ++j) {
+                                in->urbs[j]->dev = umidi->chip->dev;
+                                snd_usbmidi_submit_urb(in->urbs[j], GFP_ATOMIC);
+                        }
                 }
                 if (umidi->endpoints[i].out)
                         snd_usbmidi_do_output(umidi->endpoints[i].out);
@@ -330,13 +363,14 @@ static void snd_usbmidi_error_timer(unsigned long data)
 static int send_bulk_static_data(struct snd_usb_midi_out_endpoint* ep,
                                  const void *data, int len)
 {
-        int err;
+        int err = 0;
         void *buf = kmemdup(data, len, GFP_KERNEL);
         if (!buf)
                 return -ENOMEM;
         dump_urb("sending", buf, len);
-        err = usb_bulk_msg(ep->umidi->chip->dev, ep->urb->pipe, buf, len,
-                           NULL, 250);
+        if (ep->urbs[0].urb)
+                err = usb_bulk_msg(ep->umidi->chip->dev, ep->urbs[0].urb->pipe,
+                                   buf, len, NULL, 250);
         kfree(buf);
         return err;
 }
@@ -554,9 +588,9 @@ static void snd_usbmidi_transmit_byte(struct usbmidi_out_port* port,
         }
 }
 
-static void snd_usbmidi_standard_output(struct snd_usb_midi_out_endpoint* ep)
+static void snd_usbmidi_standard_output(struct snd_usb_midi_out_endpoint* ep,
+                                        struct urb *urb)
 {
-        struct urb* urb = ep->urb;
         int p;
 
         /* FIXME: lower-numbered ports can starve higher-numbered ports */
@@ -613,14 +647,15 @@ static void snd_usbmidi_novation_input(struct snd_usb_midi_in_endpoint* ep,
         snd_usbmidi_input_data(ep, 0, &buffer[2], buffer[0] - 1);
 }
 
-static void snd_usbmidi_novation_output(struct snd_usb_midi_out_endpoint* ep)
+static void snd_usbmidi_novation_output(struct snd_usb_midi_out_endpoint* ep,
+                                        struct urb *urb)
 {
         uint8_t* transfer_buffer;
         int count;
 
         if (!ep->ports[0].active)
                 return;
-        transfer_buffer = ep->urb->transfer_buffer;
+        transfer_buffer = urb->transfer_buffer;
         count = snd_rawmidi_transmit(ep->ports[0].substream,
                                      &transfer_buffer[2],
                                      ep->max_transfer - 2);
@@ -630,7 +665,7 @@ static void snd_usbmidi_novation_output(struct snd_usb_midi_out_endpoint* ep)
         }
         transfer_buffer[0] = 0;
         transfer_buffer[1] = count;
-        ep->urb->transfer_buffer_length = 2 + count;
+        urb->transfer_buffer_length = 2 + count;
 }
 
 static struct usb_protocol_ops snd_usbmidi_novation_ops = {
@@ -648,20 +683,21 @@ static void snd_usbmidi_raw_input(struct snd_usb_midi_in_endpoint* ep,
         snd_usbmidi_input_data(ep, 0, buffer, buffer_length);
 }
 
-static void snd_usbmidi_raw_output(struct snd_usb_midi_out_endpoint* ep)
+static void snd_usbmidi_raw_output(struct snd_usb_midi_out_endpoint* ep,
+                                   struct urb *urb)
 {
         int count;
 
         if (!ep->ports[0].active)
                 return;
         count = snd_rawmidi_transmit(ep->ports[0].substream,
-                                     ep->urb->transfer_buffer,
+                                     urb->transfer_buffer,
                                      ep->max_transfer);
         if (count < 1) {
                 ep->ports[0].active = 0;
                 return;
         }
-        ep->urb->transfer_buffer_length = count;
+        urb->transfer_buffer_length = count;
 }
 
 static struct usb_protocol_ops snd_usbmidi_raw_ops = {
@@ -681,23 +717,25 @@ static void snd_usbmidi_us122l_input(struct snd_usb_midi_in_endpoint *ep,
                 snd_usbmidi_input_data(ep, 0, buffer, buffer_length);
 }
 
-static void snd_usbmidi_us122l_output(struct snd_usb_midi_out_endpoint *ep)
+static void snd_usbmidi_us122l_output(struct snd_usb_midi_out_endpoint *ep,
+                                      struct urb *urb)
 {
         int count;
 
         if (!ep->ports[0].active)
                 return;
-        count = ep->urb->dev->speed == USB_SPEED_HIGH ? 1 : 2;
+        count = snd_usb_get_speed(ep->umidi->chip->dev) == USB_SPEED_HIGH
+                ? 1 : 2;
         count = snd_rawmidi_transmit(ep->ports[0].substream,
-                                     ep->urb->transfer_buffer,
+                                     urb->transfer_buffer,
                                      count);
         if (count < 1) {
                 ep->ports[0].active = 0;
                 return;
         }
 
-        memset(ep->urb->transfer_buffer + count, 0xFD, 9 - count);
-        ep->urb->transfer_buffer_length = count;
+        memset(urb->transfer_buffer + count, 0xFD, 9 - count);
+        urb->transfer_buffer_length = count;
 }
 
 static struct usb_protocol_ops snd_usbmidi_122l_ops = {
@@ -786,10 +824,11 @@ static void snd_usbmidi_emagic_input(struct snd_usb_midi_in_endpoint* ep,
         }
 }
 
-static void snd_usbmidi_emagic_output(struct snd_usb_midi_out_endpoint* ep)
+static void snd_usbmidi_emagic_output(struct snd_usb_midi_out_endpoint* ep,
+                                      struct urb *urb)
 {
         int port0 = ep->current_port;
-        uint8_t* buf = ep->urb->transfer_buffer;
+        uint8_t* buf = urb->transfer_buffer;
         int buf_free = ep->max_transfer;
         int length, i;
 
@@ -829,7 +868,7 @@ static void snd_usbmidi_emagic_output(struct snd_usb_midi_out_endpoint* ep)
                 *buf = 0xff;
                 --buf_free;
         }
-        ep->urb->transfer_buffer_length = ep->max_transfer - buf_free;
+        urb->transfer_buffer_length = ep->max_transfer - buf_free;
 }
 
 static struct usb_protocol_ops snd_usbmidi_emagic_ops = {
@@ -884,6 +923,35 @@ static void snd_usbmidi_output_trigger(struct snd_rawmidi_substream *substream,
         }
 }
 
+static void snd_usbmidi_output_drain(struct snd_rawmidi_substream *substream)
+{
+        struct usbmidi_out_port* port = substream->runtime->private_data;
+        struct snd_usb_midi_out_endpoint *ep = port->ep;
+        unsigned int drain_urbs;
+        DEFINE_WAIT(wait);
+        long timeout = msecs_to_jiffies(50);
+
+        /*
+         * The substream buffer is empty, but some data might still be in the
+         * currently active URBs, so we have to wait for those to complete.
+         */
+        spin_lock_irq(&ep->buffer_lock);
+        drain_urbs = ep->active_urbs;
+        if (drain_urbs) {
+                ep->drain_urbs |= drain_urbs;
+                do {
+                        prepare_to_wait(&ep->drain_wait, &wait,
+                                        TASK_UNINTERRUPTIBLE);
+                        spin_unlock_irq(&ep->buffer_lock);
+                        timeout = schedule_timeout(timeout);
+                        spin_lock_irq(&ep->buffer_lock);
+                        drain_urbs &= ep->drain_urbs;
+                } while (drain_urbs && timeout);
+                finish_wait(&ep->drain_wait, &wait);
+        }
+        spin_unlock_irq(&ep->buffer_lock);
+}
+
 static int snd_usbmidi_input_open(struct snd_rawmidi_substream *substream)
 {
         return 0;
@@ -908,6 +976,7 @@ static struct snd_rawmidi_ops snd_usbmidi_output_ops = {
         .open = snd_usbmidi_output_open,
         .close = snd_usbmidi_output_close,
         .trigger = snd_usbmidi_output_trigger,
+        .drain = snd_usbmidi_output_drain,
 };
 
 static struct snd_rawmidi_ops snd_usbmidi_input_ops = {
@@ -916,19 +985,26 @@ static struct snd_rawmidi_ops snd_usbmidi_input_ops = {
         .trigger = snd_usbmidi_input_trigger
 };
 
+static void free_urb_and_buffer(struct snd_usb_midi *umidi, struct urb *urb,
+                                unsigned int buffer_length)
+{
+        usb_buffer_free(umidi->chip->dev, buffer_length,
+                        urb->transfer_buffer, urb->transfer_dma);
+        usb_free_urb(urb);
+}
+
 /*
  * Frees an input endpoint.
  * May be called when ep hasn't been initialized completely.
  */
 static void snd_usbmidi_in_endpoint_delete(struct snd_usb_midi_in_endpoint* ep)
 {
-        if (ep->urb) {
-                usb_buffer_free(ep->umidi->chip->dev,
-                                ep->urb->transfer_buffer_length,
-                                ep->urb->transfer_buffer,
-                                ep->urb->transfer_dma);
-                usb_free_urb(ep->urb);
-        }
+        unsigned int i;
+
+        for (i = 0; i < INPUT_URBS; ++i)
+                if (ep->urbs[i])
+                        free_urb_and_buffer(ep->umidi, ep->urbs[i],
+                                            ep->urbs[i]->transfer_buffer_length);
         kfree(ep);
 }
 
@@ -943,6 +1019,7 @@ static int snd_usbmidi_in_endpoint_create(struct snd_usb_midi* umidi,
         void* buffer;
         unsigned int pipe;
         int length;
+        unsigned int i;
 
         rep->in = NULL;
         ep = kzalloc(sizeof(*ep), GFP_KERNEL);
@@ -950,30 +1027,36 @@ static int snd_usbmidi_in_endpoint_create(struct snd_usb_midi* umidi,
                 return -ENOMEM;
         ep->umidi = umidi;
 
-        ep->urb = usb_alloc_urb(0, GFP_KERNEL);
-        if (!ep->urb) {
-                snd_usbmidi_in_endpoint_delete(ep);
-                return -ENOMEM;
+        for (i = 0; i < INPUT_URBS; ++i) {
+                ep->urbs[i] = usb_alloc_urb(0, GFP_KERNEL);
+                if (!ep->urbs[i]) {
+                        snd_usbmidi_in_endpoint_delete(ep);
+                        return -ENOMEM;
+                }
         }
         if (ep_info->in_interval)
                 pipe = usb_rcvintpipe(umidi->chip->dev, ep_info->in_ep);
         else
                 pipe = usb_rcvbulkpipe(umidi->chip->dev, ep_info->in_ep);
         length = usb_maxpacket(umidi->chip->dev, pipe, 0);
-        buffer = usb_buffer_alloc(umidi->chip->dev, length, GFP_KERNEL,
-                                  &ep->urb->transfer_dma);
-        if (!buffer) {
-                snd_usbmidi_in_endpoint_delete(ep);
-                return -ENOMEM;
+        for (i = 0; i < INPUT_URBS; ++i) {
+                buffer = usb_buffer_alloc(umidi->chip->dev, length, GFP_KERNEL,
+                                          &ep->urbs[i]->transfer_dma);
+                if (!buffer) {
+                        snd_usbmidi_in_endpoint_delete(ep);
+                        return -ENOMEM;
+                }
+                if (ep_info->in_interval)
+                        usb_fill_int_urb(ep->urbs[i], umidi->chip->dev,
+                                         pipe, buffer, length,
+                                         snd_usbmidi_in_urb_complete,
+                                         ep, ep_info->in_interval);
+                else
+                        usb_fill_bulk_urb(ep->urbs[i], umidi->chip->dev,
+                                          pipe, buffer, length,
+                                          snd_usbmidi_in_urb_complete, ep);
+                ep->urbs[i]->transfer_flags = URB_NO_TRANSFER_DMA_MAP;
         }
-        if (ep_info->in_interval)
-                usb_fill_int_urb(ep->urb, umidi->chip->dev, pipe, buffer,
-                                 length, snd_usbmidi_in_urb_complete, ep,
-                                 ep_info->in_interval);
-        else
-                usb_fill_bulk_urb(ep->urb, umidi->chip->dev, pipe, buffer,
-                                  length, snd_usbmidi_in_urb_complete, ep);
-        ep->urb->transfer_flags = URB_NO_TRANSFER_DMA_MAP;
 
         rep->in = ep;
         return 0;
@@ -994,12 +1077,12 @@ static unsigned int snd_usbmidi_count_bits(unsigned int x)
  */
 static void snd_usbmidi_out_endpoint_delete(struct snd_usb_midi_out_endpoint* ep)
 {
-        if (ep->urb) {
-                usb_buffer_free(ep->umidi->chip->dev, ep->max_transfer,
-                                ep->urb->transfer_buffer,
-                                ep->urb->transfer_dma);
-                usb_free_urb(ep->urb);
-        }
+        unsigned int i;
+
+        for (i = 0; i < OUTPUT_URBS; ++i)
+                if (ep->urbs[i].urb)
+                        free_urb_and_buffer(ep->umidi, ep->urbs[i].urb,
+                                            ep->max_transfer);
         kfree(ep);
 }
 
@@ -1011,7 +1094,7 @@ static int snd_usbmidi_out_endpoint_create(struct snd_usb_midi* umidi,
                                            struct snd_usb_midi_endpoint* rep)
 {
         struct snd_usb_midi_out_endpoint* ep;
-        int i;
+        unsigned int i;
         unsigned int pipe;
         void* buffer;
 
@@ -1021,38 +1104,46 @@ static int snd_usbmidi_out_endpoint_create(struct snd_usb_midi* umidi,
                 return -ENOMEM;
         ep->umidi = umidi;
 
-        ep->urb = usb_alloc_urb(0, GFP_KERNEL);
-        if (!ep->urb) {
-                snd_usbmidi_out_endpoint_delete(ep);
-                return -ENOMEM;
+        for (i = 0; i < OUTPUT_URBS; ++i) {
+                ep->urbs[i].urb = usb_alloc_urb(0, GFP_KERNEL);
+                if (!ep->urbs[i].urb) {
+                        snd_usbmidi_out_endpoint_delete(ep);
+                        return -ENOMEM;
+                }
+                ep->urbs[i].ep = ep;
         }
         if (ep_info->out_interval)
                 pipe = usb_sndintpipe(umidi->chip->dev, ep_info->out_ep);
         else
                 pipe = usb_sndbulkpipe(umidi->chip->dev, ep_info->out_ep);
         if (umidi->chip->usb_id == USB_ID(0x0a92, 0x1020)) /* ESI M4U */
-                /* FIXME: we need more URBs to get reasonable bandwidth here: */
                 ep->max_transfer = 4;
         else
                 ep->max_transfer = usb_maxpacket(umidi->chip->dev, pipe, 1);
-        buffer = usb_buffer_alloc(umidi->chip->dev, ep->max_transfer,
-                                  GFP_KERNEL, &ep->urb->transfer_dma);
-        if (!buffer) {
-                snd_usbmidi_out_endpoint_delete(ep);
-                return -ENOMEM;
+        for (i = 0; i < OUTPUT_URBS; ++i) {
+                buffer = usb_buffer_alloc(umidi->chip->dev,
+                                          ep->max_transfer, GFP_KERNEL,
+                                          &ep->urbs[i].urb->transfer_dma);
+                if (!buffer) {
+                        snd_usbmidi_out_endpoint_delete(ep);
+                        return -ENOMEM;
+                }
+                if (ep_info->out_interval)
+                        usb_fill_int_urb(ep->urbs[i].urb, umidi->chip->dev,
+                                         pipe, buffer, ep->max_transfer,
+                                         snd_usbmidi_out_urb_complete,
+                                         &ep->urbs[i], ep_info->out_interval);
+                else
+                        usb_fill_bulk_urb(ep->urbs[i].urb, umidi->chip->dev,
+                                          pipe, buffer, ep->max_transfer,
+                                          snd_usbmidi_out_urb_complete,
+                                          &ep->urbs[i]);
+                ep->urbs[i].urb->transfer_flags = URB_NO_TRANSFER_DMA_MAP;
         }
-        if (ep_info->out_interval)
-                usb_fill_int_urb(ep->urb, umidi->chip->dev, pipe, buffer,
-                                 ep->max_transfer, snd_usbmidi_out_urb_complete,
-                                 ep, ep_info->out_interval);
-        else
-                usb_fill_bulk_urb(ep->urb, umidi->chip->dev,
-                                  pipe, buffer, ep->max_transfer,
-                                  snd_usbmidi_out_urb_complete, ep);
-        ep->urb->transfer_flags = URB_NO_TRANSFER_DMA_MAP;
 
         spin_lock_init(&ep->buffer_lock);
         tasklet_init(&ep->tasklet, snd_usbmidi_out_tasklet, (unsigned long)ep);
+        init_waitqueue_head(&ep->drain_wait);
 
         for (i = 0; i < 0x10; ++i)
                 if (ep_info->out_cables & (1 << i)) {
@@ -1090,7 +1181,7 @@ static void snd_usbmidi_free(struct snd_usb_midi* umidi)
 void snd_usbmidi_disconnect(struct list_head* p)
 {
         struct snd_usb_midi* umidi;
-        int i;
+        unsigned int i, j;
 
         umidi = list_entry(p, struct snd_usb_midi, list);
         /*
@@ -1105,13 +1196,15 @@ void snd_usbmidi_disconnect(struct list_head* p)
                 struct snd_usb_midi_endpoint* ep = &umidi->endpoints[i];
                 if (ep->out)
                         tasklet_kill(&ep->out->tasklet);
-                if (ep->out && ep->out->urb) {
-                        usb_kill_urb(ep->out->urb);
+                if (ep->out) {
+                        for (j = 0; j < OUTPUT_URBS; ++j)
+                                usb_kill_urb(ep->out->urbs[j].urb);
                         if (umidi->usb_protocol_ops->finish_out_endpoint)
                                 umidi->usb_protocol_ops->finish_out_endpoint(ep->out);
                 }
                 if (ep->in)
-                        usb_kill_urb(ep->in->urb);
+                        for (j = 0; j < INPUT_URBS; ++j)
+                                usb_kill_urb(ep->in->urbs[j]);
                 /* free endpoints here; later call can result in Oops */
                 if (ep->out) {
                         snd_usbmidi_out_endpoint_delete(ep->out);
@@ -1692,20 +1785,25 @@ static int snd_usbmidi_create_rawmidi(struct snd_usb_midi* umidi,
 void snd_usbmidi_input_stop(struct list_head* p)
 {
         struct snd_usb_midi* umidi;
-        int i;
+        unsigned int i, j;
 
         umidi = list_entry(p, struct snd_usb_midi, list);
         for (i = 0; i < MIDI_MAX_ENDPOINTS; ++i) {
                 struct snd_usb_midi_endpoint* ep = &umidi->endpoints[i];
                 if (ep->in)
-                        usb_kill_urb(ep->in->urb);
+                        for (j = 0; j < INPUT_URBS; ++j)
+                                usb_kill_urb(ep->in->urbs[j]);
         }
 }
 
 static void snd_usbmidi_input_start_ep(struct snd_usb_midi_in_endpoint* ep)
 {
-        if (ep) {
-                struct urb* urb = ep->urb;
+        unsigned int i;
+
+        if (!ep)
+                return;
+        for (i = 0; i < INPUT_URBS; ++i) {
+                struct urb* urb = ep->urbs[i];
                 urb->dev = ep->umidi->chip->dev;
                 snd_usbmidi_submit_urb(urb, GFP_KERNEL);
         }