[pvrusb2] cx25840 video scaler is broken [was: Poor analog picture on HVR-1950 after upgrade...]

[Mike Isely]

On Sun, 14 Jun 2009, Roger wrote:

> On Sun, 2009-06-14 at 21:22 -0500, Mike Isely wrote:
> > On Sun, 14 Jun 2009, Roger wrote:
> > > Never knew about this site either.  Isn't much use except noting the fact,
> > > "using mythtv-setup as user instead of root" will spawn errors when accessing
> > > /dev/video0 for the HVR-1950.
> > 
> > That note is not entirely correct, at least probably in how you quoted 
> > it.  The UID one uses to access /dev/video0 depends on how the device 
> > node has been set up by udev in your distro.  It has nothing to do with 
> > the driver, and it ESPECIALLY has nothing to do with the hardware 
> > sitting on the other side of the driver.
> > 
> > Generally unless a distro does something special here, e.g. configure 
> > udev to assign group "video" to all V4L & DVB device nodes, then root is 
> > the only thing that can really do anything here.  But a better approach 
> > is to assign a specific group to the node, e.g. 'video'.  Then any user 
> > associated with that group can have greater access (usually full 
> > access).  It's just a question of uid, gid associated with the node and 
> > whatever mode bits have been set - none of which has anything at all to 
> > do with the underlying driver or its hardware.
> 
> This is exactly what I thought too.  However,
> 
> $ ls -alh /dev/video?
> crw-rw---- 1 root video 81, 0 Jun 13 15:05 /dev/video0
> crw-rw---- 1 root video 81, 2 Jun 13 15:05 /dev/video1
> 
> $ cat /etc/group |grep video
> video:x:27:root,roger,mythtv

User root does not need to be listed.  The device node is already r/w 
for root and that's enough.

As I said, none of the above is specific to HVR-1950.

> 
> 
> Executing mythtv-setup as root has no effect here -- after stopping the
> backend (with the conflicting EIT scan).
> 
> I still get the multiple "Card 3 (type Could not open '/dev/video1' to )
> is set to start on channel  Please add, which does not exist." errors on
> mythtv-setup exit. 
> 
> Guess this guy's theory isn't correct. :-/
> 

You're really talking about mythtv stuff here, not pvrusb2 
driver-specific stuff.

Whatever.

  -Mike


-- 

Mike Isely
isely @ isely (dot) net
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