drivers/usb/serial/usb_debug.c

   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/tty.h>
  14 #include <linux/module.h>
  15 #include <linux/usb.h>
  16 #include <linux/usb/serial.h>
  17
  18 #define USB_DEBUG_MAX_PACKET_SIZE       8
  19 #define USB_DEBUG_BRK_SIZE              8
  20 static const char USB_DEBUG_BRK[USB_DEBUG_BRK_SIZE] = {
  21         0x00,
  22         0xff,
  23         0x01,
  24         0xfe,
  25         0x00,
  26         0xfe,
  27         0x01,
  28         0xff,
  29 };
  30
  31 static const struct usb_device_id id_table[] = {
  32         { USB_DEVICE(0x0525, 0x127a) },
  33         { },
  34 };
  35
  36 static const struct usb_device_id dbc_id_table[] = {
  37         { USB_DEVICE(0x1d6b, 0x0010) },
  38         { USB_DEVICE(0x1d6b, 0x0011) },
  39         { },
  40 };
  41
  42 static const struct usb_device_id id_table_combined[] = {
  43         { USB_DEVICE(0x0525, 0x127a) },
  44         { USB_DEVICE(0x1d6b, 0x0010) },
  45         { USB_DEVICE(0x1d6b, 0x0011) },
  46         { },
  47 };
  48 MODULE_DEVICE_TABLE(usb, id_table_combined);
  49
  50 /* This HW really does not support a serial break, so one will be
  51  * emulated when ever the break state is set to true.
  52  */
  53 static void usb_debug_break_ctl(struct tty_struct *tty, int break_state)
  54 {
  55         struct usb_serial_port *port = tty->driver_data;
  56         if (!break_state)
  57                 return;
  58         usb_serial_generic_write(tty, port, USB_DEBUG_BRK, USB_DEBUG_BRK_SIZE);
  59 }
  60
  61 static void usb_debug_process_read_urb(struct urb *urb)
  62 {
  63         struct usb_serial_port *port = urb->context;
  64
  65         if (urb->actual_length == USB_DEBUG_BRK_SIZE &&
  66                 memcmp(urb->transfer_buffer, USB_DEBUG_BRK,
  67                                                 USB_DEBUG_BRK_SIZE) == 0) {
  68                 usb_serial_handle_break(port);
  69                 return;
  70         }
  71
  72         usb_serial_generic_process_read_urb(urb);
  73 }
  74
  75 static struct usb_serial_driver debug_device = {
  76         .driver = {
  77                 .owner =        THIS_MODULE,
  78                 .name =         "debug",
  79         },
  80         .id_table =             id_table,
  81         .num_ports =            1,
  82         .bulk_out_size =        USB_DEBUG_MAX_PACKET_SIZE,
  83         .break_ctl =            usb_debug_break_ctl,
  84         .process_read_urb =     usb_debug_process_read_urb,
  85 };
  86
  87 static struct usb_serial_driver dbc_device = {
  88         .driver = {
  89                 .owner =        THIS_MODULE,
  90                 .name =         "xhci_dbc",
  91         },
  92         .id_table =             dbc_id_table,
  93         .num_ports =            1,
  94         .break_ctl =            usb_debug_break_ctl,
  95         .process_read_urb =     usb_debug_process_read_urb,
  96 };
  97
  98 static struct usb_serial_driver * const serial_drivers[] = {
  99         &debug_device, &dbc_device, NULL
 100 };
 101
 102 module_usb_serial_driver(serial_drivers, id_table_combined);
 103 MODULE_LICENSE("GPL");