[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 07:55 -0700, Nicholas Robbins wrote:
> > 
> > 
> > I use it only in analog mode through mythtv. The wiki at mythtv.org points to this:
> > 
> > http://sray.squidpower.com/2009/02/18/hauppauge-wintv-hvr-1950-on-linux-mythbuntu-mythtv-analog-digital-video-including-s-video-and-composite-inputs/  
> 
> 

> 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.


> 
> I never knew this until now.  How irritating this wasn't posted to the
> pvrusb2 mailing list!

Don't get worked up over it.  The Internet is a big place.

  -Mike


-- 

Mike Isely
isely @ isely (dot) net
PGP: 03 54 43 4D 75 E5 CC 92 71 16 01 E2 B5 F5 C1 E8