[pvrusb2] mythtv and wintv-hvr-1950 - analog/digital scanning

[Mike Isely]

On Tue, 6 Jan 2009, fivenote wrote:

> Maybe this isn't new info, but to be clear, when doing a cat
> /dev/video0 I noticed I'm getting two log messages...
> 
> Jan  6 22:12:35 vao1420 kernel: [ 7348.565024] firmware: requesting
> v4l-cx2341x-enc.fw
> Jan  6 22:12:36 vao1420 kernel: [ 7348.951037] pvrusb2: WARNING: No
> decoder present
> 
> I think the firmware one is ok. The firmware file was extracted and
> placed with the others in my /lib/firmware so it should be finding it.

You're basically right.

There is a state machine in the driver that tries to carefully 
orchestrate startup / shutdown of the video pipeline.  This state 
machine becomes even more complex in the case of the HVR-1950 due to the 
fact that the digital side effectively defines a second, different, but 
partially shared video pipeline through the device.  Anyway, we know now 
that the driver is leaving itself in an error state due to the 
unrecognized cx25840 module.  The state machine tries to reset itself 
from the error state when you re-open the device and attempt to stream.  
Very likely it is "playing it safe" and kicking the mpeg encoder each 
time when attempting to come out of the error state.  So the firmware 
message is harmless.

  -Mike

-- 

Mike Isely
isely @ pobox (dot) com
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