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 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 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 .no_dynamic_id = 1, 44 }; 45 46 static 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 */ 55 static 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 63 static 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 78 static 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 91 static 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 } 103 104 static void __exit debug_exit(void) 105 { 106 usb_deregister(&debug_driver); 107 usb_serial_deregister(&debug_device); 108 } 109 110 module_init(debug_init); 111 module_exit(debug_exit); 112 MODULE_LICENSE("GPL"); 113