南昌网站开发技术,单位制作网站备案,汉中网站开发,网站预算本系列解析usbseiral ko的源码#xff0c;记录主要函数#xff0c;调用流程#xff0c;USB一端和串口一端的注册流程#xff0c;本节简介主要函数以及替换规则。 首先#xff0c;usbserial是USB转串口驱动的一个基础模板#xff0c;其中有许多默认函数#xff0c;他们的…本系列解析usbseiral ko的源码记录主要函数调用流程USB一端和串口一端的注册流程本节简介主要函数以及替换规则。 首先usbserial是USB转串口驱动的一个基础模板其中有许多默认函数他们的定义方式如下 const struct bus_type usb_serial_bus_type {.name usb-serial,.match usb_serial_device_match,.probe usb_serial_device_probe,.remove usb_serial_device_remove,.drv_groups usb_serial_drv_groups, }; static struct usb_serial_driver usb_serial_generic_device {.driver {.owner THIS_MODULE,.name generic,},.id_table generic_device_ids,.probe usb_serial_generic_probe,.calc_num_ports usb_serial_generic_calc_num_ports,.throttle usb_serial_generic_throttle,.unthrottle usb_serial_generic_unthrottle,.resume usb_serial_generic_resume, }; static const struct tty_port_operations serial_port_ops {.carrier_raised serial_port_carrier_raised,.dtr_rts serial_port_dtr_rts,.activate serial_port_activate,.shutdown serial_port_shutdown, }; static const struct tty_operations serial_ops {.open serial_open,.close serial_close,.write serial_write,.hangup serial_hangup,.write_room serial_write_room,.ioctl serial_ioctl,.set_termios serial_set_termios,.throttle serial_throttle,.unthrottle serial_unthrottle,.break_ctl serial_break,.chars_in_buffer serial_chars_in_buffer,.wait_until_sent serial_wait_until_sent,.tiocmget serial_tiocmget,.tiocmset serial_tiocmset,.get_icount serial_get_icount,.set_serial serial_set_serial,.get_serial serial_get_serial,.cleanup serial_cleanup,.install serial_install,.proc_show serial_proc_show, }; 其中tty operation中有部分函数可以被替换掉替换的过程如下 static void usb_serial_operations_init(struct usb_serial_driver *device) {set_to_generic_if_null(device, open);set_to_generic_if_null(device, write);set_to_generic_if_null(device, close);set_to_generic_if_null(device, write_room);set_to_generic_if_null(device, chars_in_buffer);if (device-tx_empty)set_to_generic_if_null(device, wait_until_sent);set_to_generic_if_null(device, read_bulk_callback);set_to_generic_if_null(device, write_bulk_callback);set_to_generic_if_null(device, process_read_urb);set_to_generic_if_null(device, prepare_write_buffer); } 可见open、write、close、write_room、chars_in_buffer、read_bulk_callback、write_bulk_callback、process_read_urb、prepare_write_buffer函数可以被替换掉不过有些函数采取的是插入的方式目的是在generic的基础上增加一些属vendor的其他操作比如probe 以generic 的probe为例子usbseiral设备在被probe的时候一定会进行search_serial_device、create_serial等等操作然后再简单的打印一些信息——如果有一些vendor specific的probe操作可以单独添加——endpoint的查找在vendor的probe的后面也是一定会进行的。