HVR-950q, em28xx GPIOs, and Dib0700 Firmware

Did some more testing of the HVR-950q under MythTV. Wrote some patches to get rid of a couple of spurious error messages. However, in the end the code currently in the v4l-dvb codebase today does work with MythTV, as long as you have the latest snapshot of 0.22, use the no_poweroff xc5000 modprobe option, and make sure that the capture profile is set to 720×480. It’s worth noting that Ubuntu Karmic has already picked up the changes, so if you are tracking the bleeding edge Karmic release then you have the fix.

There’s still the problem with the audio squelch during channel changes. I spent some time working on that last night, and it’s not clear where it is coming from. It occurs even when I properly program the softmute registers in the au8522.

I’ve been going back and forth on the linux-media mailing list with users of various em28xx hybrid devices. I believe I have found a problem with the way we put the device to sleep when not in use that probably explains why certain tuning scenarios fail with all the em28xx devices that have the zl10353. Working on a fix for that and hope to have it merged this week.

Speaking of Ubuntu Karmic, a few weeks ago they moved a number of DVB firmware blobs that didn’t have clear licensing to a new module called “linux-firmware-nonfree”, which is not installed by default. While I don’t question the logic behind this given the legal issues, they did it pretty late in their release cycle (Alpha 6). Fortunately, with Patrick Boettcher’s help, we were able to get DiBcom to provide the version 1.20 firmware under a redistributable license, which has been merged into David Woodhouse’s linux-firmware tree and as of this evening pulled into Karmic.


This whole episode could have been a case where users downloaded Ubuntu 9.10 when it was released and were very confused when their tuners that worked fine in 9.04 stopped working under 9.10. It provides me some reassurance that there is value to running the Ubuntu bleeding edge in my development environment, since it allows us to catch these things before the product is released.

8 thoughts on “HVR-950q, em28xx GPIOs, and Dib0700 Firmware

  1. Hello Corey,

    Regarding the firmware – the firmware in question is actually for the dib0700, which is used by products other than the HVR-950q. On the other hand, we got the Xceive firmware required by the HVR-950q got bundled as well a couple of months ago, so the 950q should work out-of-the-box with no need to go find the firmware.

    I’m not sure why you’re having trouble with audio under 9.10. I didn’t see any issues here. Can you describe in more detail what problem you are having?


    • Hi Devin,

      Honestly, I didn’t think it was an issue with the driver itself. I believe the problem may lie with Pulseaudio. The problem i’m getting is that I can see the tv tuner working fine in TVtime for example, but there is no audio. I’ve messed with every setting in the control panel in Ubuntu 9.10, and nothing will allow sound to come out. While in the sound panel, under Input, I can select the HVR950Q device, and the audio meter actually moves back and forth like its reading audio, but nothing comes out. Seems to be some sort of audio routing issue.

      Anyways, i’ve opened a topic on the ubuntu forums, and a few other people are having the same problem. So, I guess the next step will be to file a bug report, but its way too late to get it fixed before 9.10.

      • How was it working in 9.04 then? The tvtime audio has *never* worked for the 950q in 9.04, 9.10 or any other version. The tvtime audio only works with cards that have a dedicated line-out cable hooked to external speakers.

        One of the big problems I’ve been looking to fix for a while is related to making apps like tvtime work properly with tuners that provide an alsa device (hvr-950q, all the em28xx devices, cx88 devices, saa7134, etc). This is entirely a change to the application though and not the driver.

        In order to do audio in tvtime, you need to use a combination of arecord and aplay in a separate window.


        • I have no idea how it was working. I only bought the HVR950Q in late August, and I was so happy that it worked with TVtime cause my last tuner (HVR1600) didn’t work with it while my much older WinFast TV2000XP did. I had it running with TVtime before I upgraded to 9.10, came across these audio issues, so I wiped out and re-installed 9.04, and TVtime is working fine for me. There’s a slight delay when switching channels, but other than that, everything is good.

          That combination of aplay/arecord works in 9.10, but its a bit laggy from the video.

          So, if TVtime *isn’t* supposed to work, what programs *should* work?

          • Ok, now I’m a bit confused. You’re saying that under Ubuntu 9.04, the audio in tvtime works with the HVR-950q, *without* running arecord/aplay?


  2. Ok, I must have been on something for the last two months because now that I have 9.04 back on my system, my tuner no longer works in TVtime. I’m 99.5% sure that it was working cause i remember the picture being “jittery” while the audio was just fine. But, you are the expert, so I will heed to your expertise and say that I must have imagined it.

    With that said, what is the “proper” way to watch tv with these cards other than using a huge program like MythTV?

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