1 files changed, 64 insertions, 13 deletions

diff --git a/sound/usb/usbmidi.c b/sound/usb/usbmidi.c
index 5f19b494923e..93dedde3c428 100644
--- a/sound/usb/usbmidi.c
+++ b/sound/usb/usbmidi.c
@@ -44,6 +44,7 @@
 #include <linux/string.h>
 #include <linux/init.h>
 #include <linux/slab.h>
+#include <linux/timer.h>
 #include <linux/usb.h>
 #include <sound/core.h>
 #include <sound/minors.h>
@@ -56,6 +57,12 @@
  */
 /* #define DUMP_PACKETS */
 
+/*
+ * how long to wait after some USB errors, so that khubd can disconnect() us
+ * without too many spurious errors
+ */
+#define ERROR_DELAY_JIFFIES (HZ / 10)
+
 
 MODULE_AUTHOR("Clemens Ladisch <clemens@ladisch.de>");
 MODULE_DESCRIPTION("USB Audio/MIDI helper module");
@@ -100,6 +107,7 @@ struct snd_usb_midi {
         snd_rawmidi_t* rmidi;
         struct usb_protocol_ops* usb_protocol_ops;
         struct list_head list;
+        struct timer_list error_timer;
 
         struct snd_usb_midi_endpoint {
                 snd_usb_midi_out_endpoint_t *out;
@@ -141,7 +149,8 @@ struct snd_usb_midi_in_endpoint {
         struct usbmidi_in_port {
                 snd_rawmidi_substream_t* substream;
         } ports[0x10];
-        int seen_f5;
+        u8 seen_f5;
+        u8 error_resubmit;
         int current_port;
 };
 
@@ -167,14 +176,22 @@ static int snd_usbmidi_submit_urb(struct urb* urb, int flags)
  */
 static int snd_usbmidi_urb_error(int status)
 {
-        if (status == -ENOENT)
-                return status; /* killed */
-        if (status == -EILSEQ ||
-            status == -ECONNRESET ||
-            status == -ETIMEDOUT)
-                return -ENODEV; /* device removed/shutdown */
-        snd_printk(KERN_ERR "urb status %d\n", status);
-        return 0; /* continue */
+        switch (status) {
+        /* manually unlinked, or device gone */
+        case -ENOENT:
+        case -ECONNRESET:
+        case -ESHUTDOWN:
+        case -ENODEV:
+                return -ENODEV;
+        /* errors that might occur during unplugging */
+        case -EPROTO:    /* EHCI */
+        case -ETIMEDOUT: /* OHCI */
+        case -EILSEQ:    /* UHCI */
+                return -EIO;
+        default:
+                snd_printk(KERN_ERR "urb status %d\n", status);
+                return 0; /* continue */
+        }
 }
 
 /*
@@ -218,8 +235,15 @@ static void snd_usbmidi_in_urb_complete(struct urb* urb, struct pt_regs *regs)
                 ep->umidi->usb_protocol_ops->input(ep, urb->transfer_buffer,
                                                    urb->actual_length);
         } else {
-                if (snd_usbmidi_urb_error(urb->status) < 0)
+                int err = snd_usbmidi_urb_error(urb->status);
+                if (err < 0) {
+                        if (err != -ENODEV) {
+                                ep->error_resubmit = 1;
+                                mod_timer(&ep->umidi->error_timer,
+                                          jiffies + ERROR_DELAY_JIFFIES);
+                        }
                         return;
+                }
         }
 
         if (usb_pipe_needs_resubmit(urb->pipe)) {
@@ -236,8 +260,13 @@ static void snd_usbmidi_out_urb_complete(struct urb* urb, struct pt_regs *regs)
         ep->urb_active = 0;
         spin_unlock(&ep->buffer_lock);
         if (urb->status < 0) {
-                if (snd_usbmidi_urb_error(urb->status) < 0)
+                int err = snd_usbmidi_urb_error(urb->status);
+                if (err < 0) {
+                        if (err != -ENODEV)
+                                mod_timer(&ep->umidi->error_timer,
+                                          jiffies + ERROR_DELAY_JIFFIES);
                         return;
+                }
         }
         snd_usbmidi_do_output(ep);
 }
@@ -276,6 +305,24 @@ static void snd_usbmidi_out_tasklet(unsigned long data)
         snd_usbmidi_do_output(ep);
 }
 
+/* called after transfers had been interrupted due to some USB error */
+static void snd_usbmidi_error_timer(unsigned long data)
+{
+        snd_usb_midi_t *umidi = (snd_usb_midi_t *)data;
+        int i;
+
+        for (i = 0; i < MIDI_MAX_ENDPOINTS; ++i) {
+                snd_usb_midi_in_endpoint_t *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);
+                }
+                if (umidi->endpoints[i].out)
+                        snd_usbmidi_do_output(umidi->endpoints[i].out);
+        }
+}
+
 /* helper function to send static data that may not DMA-able */
 static int send_bulk_static_data(snd_usb_midi_out_endpoint_t* ep,
                                  const void *data, int len)
@@ -844,8 +891,6 @@ static unsigned int snd_usbmidi_count_bits(unsigned int x)
  */
 static void snd_usbmidi_out_endpoint_delete(snd_usb_midi_out_endpoint_t* ep)
 {
-        if (ep->tasklet.func)
-                tasklet_kill(&ep->tasklet);
         if (ep->urb) {
                 usb_buffer_free(ep->umidi->chip->dev, ep->max_transfer,
                                 ep->urb->transfer_buffer,
@@ -934,8 +979,11 @@ void snd_usbmidi_disconnect(struct list_head* p)
         int i;
 
         umidi = list_entry(p, snd_usb_midi_t, list);
+        del_timer_sync(&umidi->error_timer);
         for (i = 0; i < MIDI_MAX_ENDPOINTS; ++i) {
                 snd_usb_midi_endpoint_t* 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 (umidi->usb_protocol_ops->finish_out_endpoint)
@@ -1496,6 +1544,9 @@ int snd_usb_create_midi_interface(snd_usb_audio_t* chip,
         umidi->iface = iface;
         umidi->quirk = quirk;
         umidi->usb_protocol_ops = &snd_usbmidi_standard_ops;
+        init_timer(&umidi->error_timer);
+        umidi->error_timer.function = snd_usbmidi_error_timer;
+        umidi->error_timer.data = (unsigned long)umidi;
 
         /* detect the endpoint(s) to use */
         memset(endpoints, 0, sizeof(endpoints));