1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
|
/*
* USB Serial Converter Bus specific functions
*
* Copyright (C) 2002 Greg Kroah-Hartman (greg@kroah.com)
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License version
* 2 as published by the Free Software Foundation.
*/
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/tty.h>
#include <linux/module.h>
#include <linux/usb.h>
#include <linux/usb/serial.h>
static int usb_serial_device_match (struct device *dev, struct device_driver *drv)
{
struct usb_serial_driver *driver;
const struct usb_serial_port *port;
/*
* drivers are already assigned to ports in serial_probe so it's
* a simple check here.
*/
port = to_usb_serial_port(dev);
if (!port)
return 0;
driver = to_usb_serial_driver(drv);
if (driver == port->serial->type)
return 1;
return 0;
}
static ssize_t show_port_number(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct usb_serial_port *port = to_usb_serial_port(dev);
return sprintf(buf, "%d\n", port->number - port->serial->minor);
}
static DEVICE_ATTR(port_number, S_IRUGO, show_port_number, NULL);
static int usb_serial_device_probe (struct device *dev)
{
struct usb_serial_driver *driver;
struct usb_serial_port *port;
int retval = 0;
int minor;
port = to_usb_serial_port(dev);
if (!port) {
retval = -ENODEV;
goto exit;
}
driver = port->serial->type;
if (driver->port_probe) {
if (!try_module_get(driver->driver.owner)) {
dev_err(dev, "module get failed, exiting\n");
retval = -EIO;
goto exit;
}
retval = driver->port_probe (port);
module_put(driver->driver.owner);
if (retval)
goto exit;
}
retval = device_create_file(dev, &dev_attr_port_number);
if (retval)
goto exit;
minor = port->number;
tty_register_device (usb_serial_tty_driver, minor, dev);
dev_info(&port->serial->dev->dev,
"%s converter now attached to ttyUSB%d\n",
driver->description, minor);
exit:
return retval;
}
static int usb_serial_device_remove (struct device *dev)
{
struct usb_serial_driver *driver;
struct usb_serial_port *port;
int retval = 0;
int minor;
port = to_usb_serial_port(dev);
if (!port) {
return -ENODEV;
}
device_remove_file(&port->dev, &dev_attr_port_number);
driver = port->serial->type;
if (driver->port_remove) {
if (!try_module_get(driver->driver.owner)) {
dev_err(dev, "module get failed, exiting\n");
retval = -EIO;
goto exit;
}
retval = driver->port_remove (port);
module_put(driver->driver.owner);
}
exit:
minor = port->number;
tty_unregister_device (usb_serial_tty_driver, minor);
dev_info(dev, "%s converter now disconnected from ttyUSB%d\n",
driver->description, minor);
return retval;
}
#ifdef CONFIG_HOTPLUG
static ssize_t store_new_id(struct device_driver *driver,
const char *buf, size_t count)
{
struct usb_serial_driver *usb_drv = to_usb_serial_driver(driver);
ssize_t retval = usb_store_new_id(&usb_drv->dynids, driver, buf, count);
if (retval >= 0 && usb_drv->usb_driver != NULL)
retval = usb_store_new_id(&usb_drv->usb_driver->dynids,
&usb_drv->usb_driver->drvwrap.driver,
buf, count);
return retval;
}
static struct driver_attribute drv_attrs[] = {
__ATTR(new_id, S_IWUSR, NULL, store_new_id),
__ATTR_NULL,
};
static void free_dynids(struct usb_serial_driver *drv)
{
struct usb_dynid *dynid, *n;
spin_lock(&drv->dynids.lock);
list_for_each_entry_safe(dynid, n, &drv->dynids.list, node) {
list_del(&dynid->node);
kfree(dynid);
}
spin_unlock(&drv->dynids.lock);
}
#else
static struct driver_attribute drv_attrs[] = {
__ATTR_NULL,
};
static inline void free_dynids(struct usb_serial_driver *drv)
{
}
#endif
struct bus_type usb_serial_bus_type = {
.name = "usb-serial",
.match = usb_serial_device_match,
.probe = usb_serial_device_probe,
.remove = usb_serial_device_remove,
.drv_attrs = drv_attrs,
};
int usb_serial_bus_register(struct usb_serial_driver *driver)
{
int retval;
driver->driver.bus = &usb_serial_bus_type;
spin_lock_init(&driver->dynids.lock);
INIT_LIST_HEAD(&driver->dynids.list);
retval = driver_register(&driver->driver);
return retval;
}
void usb_serial_bus_deregister(struct usb_serial_driver *driver)
{
free_dynids(driver);
driver_unregister(&driver->driver);
}
|
