On Thu, Jul 21, 2011 at 02:59:03PM -0700, Sarah Sharp wrote: > Add a new module parameter to increase the bulk ring size. Matrix Vision > has a libusb program for their USB 2.0 cameras that submits a number of > very large transfers. The xHCI driver ends up rejecting some transfers > because it doesn't have enough room on the one bulk ring segment. By > experimentation, their program works if 20 bulk segments are allocated. > > We really need to fix this by adding dynamic ring segment allocation, but > that code is a bit complex and will take a while to write. To ensure > Matrix Vision's libusb program works when their device is connected under > an xHCI host, add a module parameter to allow users to increase the number > of bulk endpoint ring segments. This is a temporary fix, and should be > removed once the xHCI driver has dynamic segment allocation. Ick, no. Don't add module parameters ever, if at all possible, as they are a pain to maintain and use by real users, and then you need to support them for forever as problems will happen if you try to remove them on systems that were assuming they were there. Can you make this a sysfs file per host controller device instead? thanks, 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
