1 // SPDX-License-Identifier: GPL-2.0
3 * USB Debug cable driver
5 * Copyright (C) 2006 Greg Kroah-Hartman <greg@kroah.com>
9 #include <linux/kernel.h>
10 #include <linux/tty.h>
11 #include <linux/module.h>
12 #include <linux/usb.h>
13 #include <linux/usb/serial.h>
15 #define USB_DEBUG_MAX_PACKET_SIZE 8
16 #define USB_DEBUG_BRK_SIZE 8
17 static const char USB_DEBUG_BRK[USB_DEBUG_BRK_SIZE] = {
28 static const struct usb_device_id id_table[] = {
29 { USB_DEVICE(0x0525, 0x127a) },
33 static const struct usb_device_id dbc_id_table[] = {
34 { USB_DEVICE(0x1d6b, 0x0010) },
35 { USB_DEVICE(0x1d6b, 0x0011) },
39 static const struct usb_device_id id_table_combined[] = {
40 { USB_DEVICE(0x0525, 0x127a) },
41 { USB_DEVICE(0x1d6b, 0x0010) },
42 { USB_DEVICE(0x1d6b, 0x0011) },
45 MODULE_DEVICE_TABLE(usb, id_table_combined);
47 /* This HW really does not support a serial break, so one will be
48 * emulated when ever the break state is set to true.
50 static int usb_debug_break_ctl(struct tty_struct *tty, int break_state)
52 struct usb_serial_port *port = tty->driver_data;
58 ret = usb_serial_generic_write(tty, port, USB_DEBUG_BRK, USB_DEBUG_BRK_SIZE);
65 static void usb_debug_process_read_urb(struct urb *urb)
67 struct usb_serial_port *port = urb->context;
69 if (urb->actual_length == USB_DEBUG_BRK_SIZE &&
70 memcmp(urb->transfer_buffer, USB_DEBUG_BRK,
71 USB_DEBUG_BRK_SIZE) == 0) {
72 usb_serial_handle_break(port);
76 usb_serial_generic_process_read_urb(urb);
79 static void usb_debug_init_termios(struct tty_struct *tty)
81 tty->termios.c_lflag &= ~(ECHO | ECHONL);
84 static struct usb_serial_driver debug_device = {
91 .bulk_out_size = USB_DEBUG_MAX_PACKET_SIZE,
92 .break_ctl = usb_debug_break_ctl,
93 .init_termios = usb_debug_init_termios,
94 .process_read_urb = usb_debug_process_read_urb,
97 static struct usb_serial_driver dbc_device = {
102 .id_table = dbc_id_table,
104 .break_ctl = usb_debug_break_ctl,
105 .init_termios = usb_debug_init_termios,
106 .process_read_urb = usb_debug_process_read_urb,
109 static struct usb_serial_driver * const serial_drivers[] = {
110 &debug_device, &dbc_device, NULL
113 module_usb_serial_driver(serial_drivers, id_table_combined);
114 MODULE_DESCRIPTION("USB Debug cable driver");
115 MODULE_LICENSE("GPL v2");