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/gfp.h>
12 #include <linux/kernel.h>
13 #include <linux/init.h>
14 #include <linux/tty.h>
15 #include <linux/module.h>
16 #include <linux/usb.h>
17 #include <linux/usb/serial.h>
18
19 #define USB_DEBUG_MAX_PACKET_SIZE 8
20 #define USB_DEBUG_BRK_SIZE 8
21 static 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
32 static const struct usb_device_id id_table[] = {
33 { USB_DEVICE(0x0525, 0x127a) },
34 { },
35 };
36 MODULE_DEVICE_TABLE(usb, id_table);
37
38 static struct usb_driver debug_driver = {
39 .name = "debug",
40 .probe = usb_serial_probe,
41 .disconnect = usb_serial_disconnect,
42 .id_table = id_table,
43 };
44
45 /* This HW really does not support a serial break, so one will be
46 * emulated when ever the break state is set to true.
47 */
usb_debug_break_ctl(struct tty_struct * tty,int break_state)48 static void usb_debug_break_ctl(struct tty_struct *tty, int break_state)
49 {
50 struct usb_serial_port *port = tty->driver_data;
51 if (!break_state)
52 return;
53 usb_serial_generic_write(tty, port, USB_DEBUG_BRK, USB_DEBUG_BRK_SIZE);
54 }
55
usb_debug_process_read_urb(struct urb * urb)56 static void usb_debug_process_read_urb(struct urb *urb)
57 {
58 struct usb_serial_port *port = urb->context;
59
60 if (urb->actual_length == USB_DEBUG_BRK_SIZE &&
61 memcmp(urb->transfer_buffer, USB_DEBUG_BRK,
62 USB_DEBUG_BRK_SIZE) == 0) {
63 usb_serial_handle_break(port);
64 return;
65 }
66
67 usb_serial_generic_process_read_urb(urb);
68 }
69
70 static struct usb_serial_driver debug_device = {
71 .driver = {
72 .owner = THIS_MODULE,
73 .name = "debug",
74 },
75 .id_table = id_table,
76 .num_ports = 1,
77 .bulk_out_size = USB_DEBUG_MAX_PACKET_SIZE,
78 .break_ctl = usb_debug_break_ctl,
79 .process_read_urb = usb_debug_process_read_urb,
80 };
81
82 static struct usb_serial_driver * const serial_drivers[] = {
83 &debug_device, NULL
84 };
85
86 module_usb_serial_driver(debug_driver, serial_drivers);
87 MODULE_LICENSE("GPL");
88