On Sat, 14 Nov 2009, Theodore Kilgore wrote: > On Sat, 14 Nov 2009, Alan Stern wrote: > > > On Sat, 14 Nov 2009, Theodore Kilgore wrote: > > > >> First the log where it fails, done on a Dell C600 Inspiron laptop (I have > >> tested on a couple of much newer machines, too, in case you think this one > >> is too old, but with no different outcome): > > > >> Now similar lines from the log for the same camera, on a machine where the > >> camera is working properly: > > > > The first log shows that the camera was sending packets okay; the > > packets were just empty. So it's not like the camera was failing to > > work at all. The second log was the same as the first except that the > > packets were not empty; they contained data. > > > > Indeed, this is suggestive of something like not having enough power. > > > > Alan Stern > > > > Indeed, indeed. Except that being able to find a good AAA battery in the > house and putting it in the camera did not help the camera to stream, at > all. So it is something else. Well, then I'm stumped. There appear to be two possibilities. One is that the camera really is sending nonempty data packets, but for some reason uhci-hcd doesn't get the data. The only way to verify this would be to use a USB bus analyzer. The other is that the camera really is sending empty data packets. Then one has to figure out why the camera behaves differently in the two environments; presumably only the manufacturers have enough information to make that determination. Alan Stern -- 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
