Hi Stuart, > This introduces the `uart_mode` sysfs attribute as seen in the `io_ti` > USB serial driver, allowing this USB serial interface to be switched > between RS-232, 2-wire RS-485 and 4-wire RS-485. Recently I've discovered a blog post by Greg Kroah-Hartman on sysfs files [1]. I believe this information will help you to create the new file in a better way. [1] http://kroah.com/log/blog/2013/06/26/how-to-create-a-sysfs-file-correctly/ Best regards, Maksim. -- To unsubscribe from this list: send the line "unsubscribe linux-serial" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html