Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
os
linux
1/*
2 * USB Debug cable driver
3 *
4 * Copyright (C) 2006 Greg Kroah-Hartman <greg@kroah.com>
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License version
8 * 2 as published by the Free Software Foundation.
9 */
10
11#include <linux/kernel.h>
12#include <linux/init.h>
13#include <linux/tty.h>
14#include <linux/module.h>
15#include <linux/usb.h>
16#include <linux/usb/serial.h>
17
18#define URB_DEBUG_MAX_IN_FLIGHT_URBS 4000
19#define USB_DEBUG_MAX_PACKET_SIZE 8
20#define USB_DEBUG_BRK_SIZE 8
21static char USB_DEBUG_BRK[USB_DEBUG_BRK_SIZE] = {
22 0x00,
23 0xff,
24 0x01,
25 0xfe,
26 0x00,
27 0xfe,
28 0x01,
29 0xff,
30};
31
32static struct usb_device_id id_table [] = {
33 { USB_DEVICE(0x0525, 0x127a) },
34 { },
35};
36MODULE_DEVICE_TABLE(usb, id_table);
37
38static struct usb_driver debug_driver = {
39 .name = "debug",
40 .probe = usb_serial_probe,
41 .disconnect = usb_serial_disconnect,
42 .id_table = id_table,
43 .no_dynamic_id = 1,
44};
45
46static int usb_debug_open(struct tty_struct *tty, struct usb_serial_port *port)
47{
48 port->bulk_out_size = USB_DEBUG_MAX_PACKET_SIZE;
49 return usb_serial_generic_open(tty, port);
50}
51
52/* This HW really does not support a serial break, so one will be
53 * emulated when ever the break state is set to true.
54 */
55static void usb_debug_break_ctl(struct tty_struct *tty, int break_state)
56{
57 struct usb_serial_port *port = tty->driver_data;
58 if (!break_state)
59 return;
60 usb_serial_generic_write(tty, port, USB_DEBUG_BRK, USB_DEBUG_BRK_SIZE);
61}
62
63static void usb_debug_read_bulk_callback(struct urb *urb)
64{
65 struct usb_serial_port *port = urb->context;
66
67 if (urb->actual_length == USB_DEBUG_BRK_SIZE &&
68 memcmp(urb->transfer_buffer, USB_DEBUG_BRK,
69 USB_DEBUG_BRK_SIZE) == 0) {
70 usb_serial_handle_break(port);
71 usb_serial_generic_resubmit_read_urb(port, GFP_ATOMIC);
72 return;
73 }
74
75 usb_serial_generic_read_bulk_callback(urb);
76}
77
78static struct usb_serial_driver debug_device = {
79 .driver = {
80 .owner = THIS_MODULE,
81 .name = "debug",
82 },
83 .id_table = id_table,
84 .num_ports = 1,
85 .open = usb_debug_open,
86 .max_in_flight_urbs = URB_DEBUG_MAX_IN_FLIGHT_URBS,
87 .break_ctl = usb_debug_break_ctl,
88 .read_bulk_callback = usb_debug_read_bulk_callback,
89};
90
91static int __init debug_init(void)
92{
93 int retval;
94
95 retval = usb_serial_register(&debug_device);
96 if (retval)
97 return retval;
98 retval = usb_register(&debug_driver);
99 if (retval)
100 usb_serial_deregister(&debug_device);
101 return retval;
102}
103
104static void __exit debug_exit(void)
105{
106 usb_deregister(&debug_driver);
107 usb_serial_deregister(&debug_device);
108}
109
110module_init(debug_init);
111module_exit(debug_exit);
112MODULE_LICENSE("GPL");