usb-serial: fix crash when sub-driver updates firmware
[linux-2.6/mini2440.git] / drivers / usb / serial / navman.c
blobbcdcbb822705fd952863dcd5d041abef4d8daad3
1 /*
2 * Navman Serial USB driver
4 * Copyright (C) 2006 Greg Kroah-Hartman <gregkh@suse.de>
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * version 2 as published by the Free Software Foundation.
10 * TODO:
11 * Add termios method that uses copy_hw but also kills all echo
12 * flags as the navman is rx only so cannot echo.
15 #include <linux/kernel.h>
16 #include <linux/init.h>
17 #include <linux/tty.h>
18 #include <linux/tty_flip.h>
19 #include <linux/module.h>
20 #include <linux/usb.h>
21 #include <linux/usb/serial.h>
23 static int debug;
25 static struct usb_device_id id_table [] = {
26 { USB_DEVICE(0x0a99, 0x0001) }, /* Talon Technology device */
27 { },
29 MODULE_DEVICE_TABLE(usb, id_table);
31 static struct usb_driver navman_driver = {
32 .name = "navman",
33 .probe = usb_serial_probe,
34 .disconnect = usb_serial_disconnect,
35 .id_table = id_table,
36 .no_dynamic_id = 1,
39 static void navman_read_int_callback(struct urb *urb)
41 struct usb_serial_port *port = urb->context;
42 unsigned char *data = urb->transfer_buffer;
43 struct tty_struct *tty;
44 int status = urb->status;
45 int result;
47 switch (status) {
48 case 0:
49 /* success */
50 break;
51 case -ECONNRESET:
52 case -ENOENT:
53 case -ESHUTDOWN:
54 /* this urb is terminated, clean up */
55 dbg("%s - urb shutting down with status: %d",
56 __func__, status);
57 return;
58 default:
59 dbg("%s - nonzero urb status received: %d",
60 __func__, status);
61 goto exit;
64 usb_serial_debug_data(debug, &port->dev, __func__,
65 urb->actual_length, data);
67 tty = tty_port_tty_get(&port->port);
68 if (tty && urb->actual_length) {
69 tty_buffer_request_room(tty, urb->actual_length);
70 tty_insert_flip_string(tty, data, urb->actual_length);
71 tty_flip_buffer_push(tty);
73 tty_kref_put(tty);
75 exit:
76 result = usb_submit_urb(urb, GFP_ATOMIC);
77 if (result)
78 dev_err(&urb->dev->dev,
79 "%s - Error %d submitting interrupt urb\n",
80 __func__, result);
83 static int navman_open(struct tty_struct *tty,
84 struct usb_serial_port *port, struct file *filp)
86 int result = 0;
88 dbg("%s - port %d", __func__, port->number);
90 if (port->interrupt_in_urb) {
91 dbg("%s - adding interrupt input for treo", __func__);
92 result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
93 if (result)
94 dev_err(&port->dev,
95 "%s - failed submitting interrupt urb, error %d\n",
96 __func__, result);
98 return result;
101 static void navman_close(struct tty_struct *tty,
102 struct usb_serial_port *port, struct file *filp)
104 dbg("%s - port %d", __func__, port->number);
106 usb_kill_urb(port->interrupt_in_urb);
109 static int navman_write(struct tty_struct *tty, struct usb_serial_port *port,
110 const unsigned char *buf, int count)
112 dbg("%s - port %d", __func__, port->number);
115 * This device can't write any data, only read from the device
117 return -EOPNOTSUPP;
120 static struct usb_serial_driver navman_device = {
121 .driver = {
122 .owner = THIS_MODULE,
123 .name = "navman",
125 .id_table = id_table,
126 .usb_driver = &navman_driver,
127 .num_ports = 1,
128 .open = navman_open,
129 .close = navman_close,
130 .write = navman_write,
131 .read_int_callback = navman_read_int_callback,
134 static int __init navman_init(void)
136 int retval;
138 retval = usb_serial_register(&navman_device);
139 if (retval)
140 return retval;
141 retval = usb_register(&navman_driver);
142 if (retval)
143 usb_serial_deregister(&navman_device);
144 return retval;
147 static void __exit navman_exit(void)
149 usb_deregister(&navman_driver);
150 usb_serial_deregister(&navman_device);
153 module_init(navman_init);
154 module_exit(navman_exit);
155 MODULE_LICENSE("GPL");
157 module_param(debug, bool, S_IRUGO | S_IWUSR);
158 MODULE_PARM_DESC(debug, "Debug enabled or not");