Merge branch 'master'
[linux-2.6] / drivers / usb / serial / bus.c
1 /*
2  * USB Serial Converter Bus specific functions
3  *
4  * Copyright (C) 2002 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/config.h>
12 #include <linux/kernel.h>
13 #include <linux/errno.h>
14 #include <linux/tty.h>
15 #include <linux/module.h>
16 #include <linux/usb.h>
17 #include "usb-serial.h"
18
19 static int usb_serial_device_match (struct device *dev, struct device_driver *drv)
20 {
21         struct usb_serial_driver *driver;
22         const struct usb_serial_port *port;
23
24         /*
25          * drivers are already assigned to ports in serial_probe so it's
26          * a simple check here.
27          */
28         port = to_usb_serial_port(dev);
29         if (!port)
30                 return 0;
31
32         driver = to_usb_serial_driver(drv);
33
34         if (driver == port->serial->type)
35                 return 1;
36
37         return 0;
38 }
39
40 struct bus_type usb_serial_bus_type = {
41         .name =         "usb-serial",
42         .match =        usb_serial_device_match,
43 };
44
45 static int usb_serial_device_probe (struct device *dev)
46 {
47         struct usb_serial_driver *driver;
48         struct usb_serial_port *port;
49         int retval = 0;
50         int minor;
51
52         port = to_usb_serial_port(dev);
53         if (!port) {
54                 retval = -ENODEV;
55                 goto exit;
56         }
57
58         driver = port->serial->type;
59         if (driver->port_probe) {
60                 if (!try_module_get(driver->driver.owner)) {
61                         dev_err(dev, "module get failed, exiting\n");
62                         retval = -EIO;
63                         goto exit;
64                 }
65                 retval = driver->port_probe (port);
66                 module_put(driver->driver.owner);
67                 if (retval)
68                         goto exit;
69         }
70
71         minor = port->number;
72         tty_register_device (usb_serial_tty_driver, minor, dev);
73         dev_info(&port->serial->dev->dev, 
74                  "%s converter now attached to ttyUSB%d\n",
75                  driver->description, minor);
76
77 exit:
78         return retval;
79 }
80
81 static int usb_serial_device_remove (struct device *dev)
82 {
83         struct usb_serial_driver *driver;
84         struct usb_serial_port *port;
85         int retval = 0;
86         int minor;
87
88         port = to_usb_serial_port(dev);
89         if (!port) {
90                 return -ENODEV;
91         }
92
93         driver = port->serial->type;
94         if (driver->port_remove) {
95                 if (!try_module_get(driver->driver.owner)) {
96                         dev_err(dev, "module get failed, exiting\n");
97                         retval = -EIO;
98                         goto exit;
99                 }
100                 retval = driver->port_remove (port);
101                 module_put(driver->driver.owner);
102         }
103 exit:
104         minor = port->number;
105         tty_unregister_device (usb_serial_tty_driver, minor);
106         dev_info(dev, "%s converter now disconnected from ttyUSB%d\n",
107                  driver->description, minor);
108
109         return retval;
110 }
111
112 int usb_serial_bus_register(struct usb_serial_driver *driver)
113 {
114         int retval;
115
116         driver->driver.bus = &usb_serial_bus_type;
117         driver->driver.probe = usb_serial_device_probe;
118         driver->driver.remove = usb_serial_device_remove;
119
120         retval = driver_register(&driver->driver);
121
122         return retval;
123 }
124
125 void usb_serial_bus_deregister(struct usb_serial_driver *driver)
126 {
127         driver_unregister(&driver->driver);
128 }
129