Jan-Matthias Braun spotted the problem that once the ring buffer

of comedi has run empty the next read command would block forever
even after new data has arrived. Thanks for Jan-Matthias and Ian
who fixed the bug.

diff --git a/comedi/drivers/usbdux.c b/comedi/drivers/usbdux.c
index 7fabeee6032871b32dc2346b47719b11ac0d8a83..1a42d6c5a28f706492207b6ba7e26a6b7fec0676 100644 (file)
--- a/comedi/drivers/usbdux.c
+++ b/comedi/drivers/usbdux.c
@@ -1,4 +1,4 @@
-#define DRIVER_VERSION "v2.3"
+#define DRIVER_VERSION "v2.4"
 #define DRIVER_AUTHOR "Bernd Porr, BerndPorr@f2s.com"
 #define DRIVER_DESC "Stirling/ITL USB-DUX -- Bernd.Porr@f2s.com"
 /*
@@ -77,6 +77,8 @@ sampling rate. If you sample two channels you get 4kHz and so on.
  * 2.1:  changed PWM API
  * 2.2:  added firmware kernel request to fix an udev problem
  * 2.3:  fixed a timeout bug with newer kernels (>2.6.30)
+ * 2.4:  fixed a bug which causes the driver to hang when it ran out of data.
+ *       Thanks to Jan-Matthias Braun and Ian to spot the bug and fix it.
  */
 
 // generates loads of debug info
@@ -538,6 +540,7 @@ static void usbduxsub_ai_IsocIrq(struct urb *urb PT_REGS_ARG)
                }       
        }
        // tell comedi that data is there
+       s->async->events |= COMEDI_CB_BLOCK | COMEDI_CB_EOS;
        comedi_event(this_usbduxsub->comedidev, s);
 }