[pvrusb2] pvrusb2 timeout?

[Mike Isely]

On Tue, 16 Sep 2008, Scott Doty wrote:

> Dan Bodoh wrote:
> > The timeout started again today, when I went to watch Live TV in myth:
> >
> > (from mythbackend.log)
> >
> > 2008-09-01 09:06:39.205 TVRec(3): Changing from None to WatchingLiveTV
> > 2008-09-01 09:06:39.224 TVRec(3): HW Tuner: 3->3
> > 2008-09-01 09:06:42.123
> >
> > Not ivtv driver??
> >
> >
> > 2008-09-01 09:06:42.125 AutoExpire: CalcParams(): Max required Free Space: 2.0 G
> > B w/freq: 15 min
> > 2008-09-01 09:06:47.205 MPEGRec(/dev/pvrusb2) Error: select timeout -
> > ivtv driver has stopped responding
> > 2008-09-01 09:06:48.712 TVRec(3): Changing from WatchingLiveTV to None
> > ---------
> >
> > As I repeatedly tried to watch, sometimes I would see the LED on the
> > pvr box blink as if it was being reset, and sometimes I would NOT see
> > it blink.
> >
> > But, interestingly, there is nothing emitted into the kernel log by
> > pvrusb2 during this time.  Similar to my previous experiences, the
> > pvrusb2 driver isn't logging any attempt to reset the device.
> >
> > To recover the driver, I simply unplug and plug the USB connection to
> > the device.  The pvrusb2 driver reloads, and it works just fine!
> >   
> 
> Same here, and mine is occasionally dropping out, even when plugged into
> my UPS.  :/

I wish I could suggest something new here, but I can't :-( Best that can 
be done is to try and extract as much information as possible out of the 
driver (e.g. turn on lots of logging) and hope to catch it in the act.  
I have never been able to create any scenario here where the driver 
stops mid-stream, which if I understand this problem correctly, is what 
is happening.  The *only* explanation I can come up with is that the 
hardware is physically crashing, either due to a power glitch or perhaps 
from getting too hot.


> 
> BTW, I've also noticed that if I reset the pvrusb2 with mythbackend
> trying to access it, mythbackend gets a bus error, and dies.

This does not surprise me.  If you reset the device, then it's going to 
disappear from the system momentarily while everything reinitializes.  I 
have found in the past that the mythbackend does not handle corner cases 
very well, from my own hard experience with other capture devices.  If 
any app is touching the device when the hardware is reset (power 
cycling, replugged, etc), the pvrusb2 driver will (should) gracefully 
handle this by sending an EOF to the application and then waiting for 
the application to close down and go away.  But it's up to the 
application regarding how it reacts to that.

  -Mike


-- 

Mike Isely
isely @ pobox (dot) com
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