tree e898ee29e49ae3cef7440dfeb7f9972126b3fd06
parent d568121ce3151c36cc4718dd4e977f217c6144c2
author Clemens Ladisch <[EMAIL PROTECTED]> Tue, 02 Aug 2005 15:26:52 +0200
committer Jaroslav Kysela <[EMAIL PROTECTED]> Tue, 30 Aug 2005 13:14:13 +0200

[ALSA] usb-audio: throttle MIDI URB resubmits on USB errors

USB generic driver
When a USB error occurs that might indicate that the device has been
unplugged, don't resubmit the URB immediately to prevent flooding the
log with error messages before khubd has us disconnect()ed.

Signed-off-by: Clemens Ladisch <[EMAIL PROTECTED]>

 sound/usb/usbmidi.c |   77 +++++++++++++++++++++++++++++++++++++++++++---------
 1 files changed, 64 insertions(+), 13 deletions(-)

diff --git a/sound/usb/usbmidi.c b/sound/usb/usbmidi.c
--- 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 <[EMAIL PROTECTED]>");
 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
  */
 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(
                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
        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(unsi
        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_bi
  */
 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_
        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_us
        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));
-
To unsubscribe from this list: send the line "unsubscribe git-commits-head" in
the body of a message to [EMAIL PROTECTED]
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Reply via email to