On Tue, Mar 22, 2011 at 11:43:18AM +0100, Johan Hovold wrote: > On Thu, Mar 17, 2011 at 09:06:15AM -0700, Greg KH wrote: > > On Thu, Mar 17, 2011 at 12:42:58PM +0100, Johan Hovold wrote: > > > > So, want me to delete it? > > > > > > Yes, that is likely the best way forward, but let me just have closer > > > look at the cdc-acm driver first. It seems there are some issues that > > > need to be resolved. > > > > Ok, let me know what you find out so that I can remove the driver if > > needed. > > The SAM-BA tools seems to work with cdc-acm except for the trivial (but > highly annoying) issue with the required ttyUSB symlink. > > There is one more issue, though; the SAM-BA devices can not handle > merged write request, that is, (at least to me) they seem to be > violating the cdc specification: > > "The data is always a byte stream. The Data Class does not define the > format of the stream, unless a protocol data wrapper is used." > > This is not any issue today, but if we were to introduce a fifo in the > cdc-acm driver as we did in usb-serial, the driver would break once > again. > > But since the devices identify themselves as CDC devices, and it indeed > works fine today, the way to deal with this is perhaps to introduce a > by-pass-fifo quirk should it ever be realised. > > Shall I submit a revert patch of sam-ba with some comments on the above? Please do. 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
