On Mon, Aug 13, 2012 at 12:01:52PM +0200, Ruben Jenster wrote: > Hi, > > I need some help debugging a USB transfer problem on my raspberry pi. > I know this is not a mainstream kernel issue but I would be glad if someone here can > help me understand and debug the problem. > > The problem is that the DVB Transport stream recorded from a usb DVB stick (cinergy htc stick) > attached to a usb hub which is attached to the raspberry pi is broken. > I use the latest media_build from linuxtv.org against a 3.1.9 raspberry pi kernel. > The same drivers from the media_build work perfectly with a 3.1.9 kernel on my thinkpad. > > [ 126.162705] tda18271: performing RF tracking filter calibration > [ 128.056572] tda18271: RF tracking filter calibration complete > [ 128.057855] em28xx #0/2-dvb: Using 5 buffers each with 64 x 940 bytes > [ 129.052712] em28xx #0/2-dvb: ISO ERROR COUNT: 1. > [ 129.052743] em28xx #0/2-dvb: URB packet 0, status -4001 [Unknown]. > [ 129.581352] em28xx #0/2-dvb: ISO ERROR COUNT: 1. > [ 129.581384] em28xx #0/2-dvb: URB packet 0, status -4001 [Unknown]. > [ 129.872090] em28xx #0/2-dvb: ISO ERROR COUNT: 1. > [ 129.872122] em28xx #0/2-dvb: URB packet 0, status -4001 [Unknown]. > [ 129.969224] em28xx #0/2-dvb: ISO ERROR COUNT: 1. > [ 129.969258] em28xx #0/2-dvb: URB packet 44, status -4001 [Unknown]. > > My assumption is that the isochronous transfer is broken for the usb host driver. After reading the code for the USB host driver for this hardware, and reading the hardware data sheet, I'm amazed that any USB devices work on this platform :) I think you are right in that isoc just doesn't work on the codebase you are trying to use, but I would try asking on the raspberry-pi kernel mailing list to see if there are any updates that you can try out for newer versions of the kernel and drivers, as I think a lot of work is going on in this area last time I looked. best of luck, greg k-h -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
