On Sat, Dec 21, 2013 at 08:19:36PM +0800, Yingchun Li wrote: > Hi, I have a box presents to PC as a CDC-ACM device. And I write an simple > Application to write data to the box by ttyACM0. > The application is a loop that write the data to box, and waiting for > the box response > the data. > The question is , after wrote the data to the box, the box will > process the data for a while. > before I read the box, it seems > the ACM driver will read the box automaticly(I find that from the usb > sniffer). and there > is a lot of READ-NAK packet. > So could the box disable the automatic read by someway such as flow > control, and > until it ready for sending response? That is not how the USB protocol works for that type of device. What is the problem with the READ-NAK packets? 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
