Archives | August 2009

Up until recently, I have been spending a lot of time fixing regressions in the sms1xxx driver caused as a result of the Siano developers forcing changes into the kernel without regression testing on Hauppauge devices. The developers claim that they have done the testing, but I have trouble believing this, as the driver has been thoroughly broken for quite some time as a result of their last "sync". As it is today, the driver is in the upstream kernel and it works, but the most recent 2.6.31-rc kernel is broken, with respect to the fact that certain features that worked properly in 2.6.30 no longer...

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Despite the lack of updates, I have been diligently working on em28xx VBI support. I spent most of the last couple of weeks struggling with the em28xx isoc format, since they provide both the VBI and video support in the same isoc stream, and don't have a specific packet type for VBI. In other words, lots of pointer arithmetic. Ever wonder what a Line 21 closed caption looks like? The x-axis shows each of the 720 bytes plotted on line 21. I was originally going to play some games with ImageMagick to convert the binary dump into an image, but since the content is 8-bit greyscale, I just...

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Some performance issues with the HVR-22x0 boards have lead me to take another look at tweaking the TDA18271 driver. Steve and I have found that tuning performance improves when the RF tracking filter calibration is performed in a specific order between the master and slave tuners. I created a new attach-time configuration option that allows for the bridge driver to request for the RF tracking filter calibration to occur at startup of the tuner driver. After some testing, we found that this alleviates the "second tuner fails to lock" issue. Until now, this type of configuration was available...

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We're looking to reports from two people that say they're having issues tuning to channels 91 and above with the HVR2250 Model 88061 / C3F2. Update: Patches for the issue are available in the saa7164-dev tree.

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I was out of town last week, so that's why there weren't any updates on my part. However, I'm "back in the saddle" and for the last couple of nights have been working on adding VBI support to the em28xx driver. I've got the isoc parsing code to work properly when VBI mode is enabled, and now need to get the ioctls setup properly and hook the VBI data into the videobuf device so it can be returned into userland. The work also uncovered several bugs in the open-source "zvbi" command line tool, so I will be working on getting some fixes upstream to improve the general reliability of that package...

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I've posted a new set of patches to the saa7164-dev tree. The significant change relates to how the driver deals with command queueing in an effort to resolve commands that have appeared to 'timeout', often seen as I2C message failures. One of the positive side effects is that these patches also lower the overall system cpu time and the platform feels much more responsive under a heavy load. I've just begun testing these patches in a private tree and initial indications are very good. Feel free to try these patches if you're experiencing bad behavior from youe HVR2200/50 driver. As always,...

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If you're running MythTV with an HVR2200 in Australia then I need to hear from you! I spent six hours over the weekend logged in remotely to an Australian users system trying to track down a problem that was seemingly preventing the driver from responding correctly after being loaded. Requests into the firmware were being ignored for an apparently unknown reason. dmesg was showing massive numbers of I2C errors and general timeout warnings. Well, after installing many different debug builds, tracing the driver manually, adding extra levels of debug, forcing certain things to happen .... nothing...

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Did some more work on the PCTV 340e. After talking to Rainer over at PCTV as well as Patrick Boettcher, it seems pretty clear that this is some sort of issue related to the dib0700 not properly handling the xc4000's clock stretching. Pretty annoying though, since the last dib0700 device I worked on required me to fix up the dib0700 i2c interface, and it seems like again the i2c master is going to need more fixes. Also continued investigation into the situation with VBI support for em28xx. After confirming that neither Hauppauge WinTV 7 nor Pinnacle TVCenter Pro supported closed captioning,...

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I'm continuing to try to flush out my backlog of patches. It turns up I missed a patch when I did the Terratec Cinergy T XS USB support, which resulted in the remote control not working. Setup a new tree and asked the user to test (since I've already sent back the hardware to the user I borrowed it from). http://kernellabs.com/hg/~dheitmueller/ttxs-remote Also setup a tree with fixes for the Geniatech x8000 for a user I helped on the #linuxtv IRC channel a couple of weeks ago. http://kernellabs.com/hg/~dheitmueller/geniatech_x8000 I started evaluating what would be required to get VBI support...

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A quick note to all readers... The kernellabs.com will be unavailable between 7PM and midnight (Eastern) on Wednesday August 5th 2009. We're taking a few hours to do some scheduled maintenance.

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