Hi, struct usb_serial_device has probe and attach callbacks. After attach is invoked, device minor numbers are allocated and then registered with driver core. So attach callback doesn't know minor number. Can a usb-serial driver know about device minor number as soon as it is registered with driver core? This is what I'm trying to do. As soon as user plugs in usb-serial device with particular vendor id and product id, my usb-serial driver is loaded which then gets notified of minor device number when the device is registered. At that time, this usb-serial driver will pass that information to another kernel module (speakup) which knows everything else needed to deal with that device. The end goal is to automatically load speakup with correct params, i.e. major and minor device numbers, as soon as a supported usb device is plugged in. We want to do this all inside kernel and without having the user to set up things in user space. Also, apart from above method, if there is some other way to achieve this then please suggest. Thanks, Okash -- 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