On Mon, 24 May 2010, Rafi Rubin wrote: > Ok, pardon that excessive attachments. Attached is a snip of the kernel code, > just the sysfs function, the user space equivalent, and logs of both (with the > time stamps cropped out for comparison. Since the logs are the same, up to the point where the interrupt-IN request is cancelled, it's logical to assume that the difference was caused by something that happened before you began the usbmon traces. Do it again, only this time start the traces before plugging in the device. That way we'll get a complete record. And don't worry about cropping out the timestamps; sometimes they reveal useful information. For example, here they would have told us if the interrupt-IN request failed because it timed out too quickly. > Also please put on slop code filter glasses before reading the code, I hold no > responsibility to damaged eyes or loss of sanity. It will be cleaned up, later. Aside from not using the predefined constants for the bRequestType values, what stands out most is that you're using I/O buffers allocated on the stack. That's a no-no (not all architectures are capable of doing DMA to stack-based locations); I/O buffers should be allocated dynamically using kmalloc. 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
