>Number:         94311
>Category:       usb
>Synopsis:       [ugen][PATCH] allow interrupt IN transactions to be affected 
>by USB_SET_TIMEOUT
>Confidential:   no
>Severity:       non-critical
>Priority:       medium
>Responsible:    freebsd-usb
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Sat Mar 11 05:50:20 GMT 2006
>Closed-Date:
>Last-Modified:
>Originator:     Lonnie Mendez
>Release:        6.1-BETA2
>Organization:
>Environment:
FreeBSD twind 6.1-BETA2 FreeBSD 6.1-BETA2 #4: Fri Mar 10 22:09:38 CST 2006     
[EMAIL PROTECTED]:/usr/src/sys/i386/compile/MYKERNEL  i386
>Description:
   While developing the usb redirector for qemu on FreeBSD I ran into the fact 
that the interrupt transaction process in ugen.c:ugen_do_read() does not allow 
for a timeout value (hangs process without O_NONBLOCK and no data).  The man 
page for ugen also does not mention that USB_SET_TIMEOUT ioctl has no effect 
for interrupt IN transaction so I'm led to believe this is a bug/feature not 
yet fixed:

     USB_SET_TIMEOUT (int)
             Set the timeout on the device operations, the time is specified
             in milliseconds.  The value 0 is used to indicate that there is
             no timeout.

   The patch below I believe corrects for this by using the timeout value that 
can be set from USB_SET_TIMEOUT ioctl in the tsleep call.  With this patch the 
redirector can maintain the KISS principle while functioning properly.
>How-To-Repeat:

>Fix:
--- sys/dev/usb/ugen.c  Fri Mar 10 23:17:56 2006
+++ sys/dev/usb/ugen.c  Fri Mar 10 22:28:32 2006
@@ -726,12 +726,15 @@
                        }
                        sce->state |= UGEN_ASLP;
                        DPRINTFN(5, ("ugenread: sleep on %p\n", sce));
-                       error = tsleep(sce, PZERO | PCATCH, "ugenri", 0);
+                       error = tsleep(sce, PZERO | PCATCH, "ugenri",
+                                       (sce->timeout*hz+999)/1000);
                        DPRINTFN(5, ("ugenread: woke, error=%d\n", error));
                        if (sc->sc_dying)
                                error = EIO;
                        if (error) {
                                sce->state &= ~UGEN_ASLP;
+                               if (error == EWOULDBLOCK)
+                                       error = ETIMEDOUT;
                                break;
                        }
                }

>Release-Note:
>Audit-Trail:
>Unformatted:
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