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 majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
