Recently, I test my usb host driver(not ehci or any widely used usb host) with a Ralink's wifi device(use a linux-3.0.39 kernel). But, if transferring data through FTP for a long time, I found that usb_hcd_link_urb_to_ep() (It is called by hcd's urb_enqueue function) returns -EPERM sometimes. After digging Ralink's wifi driver, I found, it seems that my host driver some time try to link a killing urb to ep. (The calling path of usb_kill_urb() is: rt2x00usb_watchdog()->rt2x00usb_dma_timeout()->rt2x00queue_dma_timeout()->rt2x00usb_watchdog_tx_dma()->rt2x00queue_flush_queue()->rt2x00usb_flush_queue()->rt2x00queue_for_each_entry()->rt2x00usb_flush_entry()->usb_kill_urb()? ) What I hope to know is: it a right result? or it seems there is a bug in my driver?or because my driver's speed is not high enough(It seems that it happends more frequently in a low speed)? -- 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
