Congratulations Mike! Your description of how the device initialization works makes total sense with what I observe. I always noticed that the HVR-1950 starts up in digital mode. Also, sometimes the switch to analog doesn't work smoothly. I sometimes need to restart the driver or re-power the device before the digital->analog switch works. I'm sure your work on the video standard switching will continue to improve things.
Thanks again. -vincent On Sun, Jun 14, 2009 at 1:30 AM, Mike Isely<[email protected]> wrote: > > Problem found... > > The VBI hack wasn't working for 24xxx in v4l-dvb w/ sub-device binding > because I was calling it too soon. The driver was setting up the VBI > hack, THEN loading the cx25840 firmware and initializing the device > which of course is all backwards. I've just tested a minor change to > fix this ordering and sure enough 640 is working correctly again. > > Knowing that, I had an idea about the HVR-1950 scaling problem... It's > a different but similar problem. In that case the pvrusb2 driver is > issuing a reset to the cx25840 driver whenever it switches the hardware > to analog mode. I strongly suspect that this reset action is going to > erase chip state, including whatever the VBI hack did. And even if you > don't run the device in digital mode this still happens - because the > pvrusb2 driver will infer a switch to digital mode at device > initialization in order that the DVB interface can initialize. Thus the > cx25840 hardware is NEVER correct there. This is only a theory; I > haven't tested a fix here yet (which would be to ensure the chip is > correctly reinitialized after a reset). But I'm 90% sure that this will > fix analog mode when scaling is active in the cx25840 for HVR-1950 > hardware. > > Actually, looking at the VBI setup within the cx25840 driver code, it > looks like I really should be re-issuing it any time the video standard > changes. In fact I think it's still being run too soon because the > driver is being told the video standard *after* this hack is done. So I > need to take a step back and examine this situation a little more > carefully. But it's just a matter of time - I'm pretty sure I've got > this problem under control now. > > Whee!!! > > -Mike > > > -- > > Mike Isely > isely @ isely (dot) net > PGP: 03 54 43 4D 75 E5 CC 92 71 16 01 E2 B5 F5 C1 E8 > _______________________________________________ > pvrusb2 mailing list > [email protected] > http://www.isely.net/cgi-bin/mailman/listinfo/pvrusb2 > -- ~~~~~~~~~~~~~~~~~~~~ VAO - [email protected] ~~~~~~~~~~~~~~~~~~~~ _______________________________________________ pvrusb2 mailing list [email protected] http://www.isely.net/cgi-bin/mailman/listinfo/pvrusb2
