On Sun, 14 Apr 2008, Bjorn Danielsson wrote: > My Mac Mini arrived last friday. I spent this weekend installing and > configuring Slamd64 (the x86-64 version of Slackware) and this evening > I tried the pvrusb2 driver in the 2.6.24.4 kernel. So far I have only > tested it with "cat /dev/video0 > file.mpg" and this worked perfectly > without any problems, patches, or special tricks. I used the firmware > from the ivtv page. Next weekend I will play around with some of the > ioctls, and report back here if anything unusual happens...
Glad to hear it. > > The saa7115 driver produced some curious dmesg output: > > saa7115 1-0021: Input: Composite 4 > saa7115 1-0021: Video signal: bad > saa7115 1-0021: Frequency: 50 Hz > saa7115 1-0021: Detected format: BW/No color > > OK, I can accept the "bad" video signal, but why does it say > "BW/No color"? The captured MPEG did have correct colors. > (I realize that this has nothing to the pvrusb2 driver per se) The key to that is knowing *when* it showed you that info. There is a V4L request that can be "broadcast" to all the attached drivers, which basically means "printk your status". A driver (such as pvrusb2) can trigger this request any time it wants. There are 3 cases where this happens in pvrusb2: 1. In response to a VIDIOC_LOG_STATUS ioctl(). 2. As a side effect of cat'ing out /sys/class/pvrusb2/*/debuginfo 3. As part of hardware initialization (e.g. when the device is plugged in). Case (3), as part of the setup when the device is plugged in, happens before any streaming takes place. I had implemented this towards the end of the initialization sequence as a means to log a starting point state in the driver. I had found it useful when debugging issues in the pvrusb2 that had impacted how these client drivers were starting (especially cx25840). So this is actually normal. Having a "bad" video signal is not an error; it is simply the status of the driver after initialization but before any streaming takes place. If you want to see something more interesting, cat out that debuginfo file (then check your system log) while you have a streaming operation in progress. Admittedly this feature (case 3) is less useful than it used to be. I should disable it. -Mike -- Mike Isely isely @ pobox (dot) com 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
