Re: Ooops when working with USB MIDI (2.6.33.1)

[Tvrtko Ursulin <tvrtko@ursulin.net>]

On Thursday 08 Apr 2010 13:22:36 Takashi Iwai wrote:
> > Takashi, do you remember what the original problem was?
> 
> Well, I have only a vague memory -- it's a similar scenario that some app
> still accessing after disconnection.  The URB can't be handled after
> the disconnection is finished.
> 
> I think the patch below might fix in this case.  You can try it
> instead of reverting the commit above.
> 
> 
> thanks,
> 
> Takashi
> 
> ---
> diff --git a/sound/usb/usbmidi.c b/sound/usb/usbmidi.c
> index 2c59afd..81c8d85 100644
> --- a/sound/usb/usbmidi.c
> +++ b/sound/usb/usbmidi.c
> @@ -986,6 +986,8 @@ static void snd_usbmidi_output_drain(struct
>  snd_rawmidi_substream *substream) DEFINE_WAIT(wait);
>  	long timeout = msecs_to_jiffies(50);
> 
> +	if (ep->umidi->disconnected)
> +		return;
>  	/*
>  	 * 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.
> @@ -1275,6 +1277,11 @@ void snd_usbmidi_disconnect(struct list_head* p)
>  			snd_usbmidi_in_endpoint_delete(ep->in);
>  			ep->in = NULL;
>  		}
> +		ep->active_urbs = 0;
> +		if (ep->drain_urbs) {
> +			ep->drain_urbs = 0;
> +			wake_up(&ep->drain_wait);
> +		}
>  	}
>  	del_timer_sync(&umidi->error_timer);
>  }

For the second hunk, do you think ep->out->... and so on? That would be more 
in-line with code present in 2.6.33.

Tvrtko