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/kernel.h>
12#include <linux/errno.h>
13#include <linux/tty.h>
14#include <linux/module.h>
15#include <linux/usb.h>
16#include <linux/usb/serial.h>
17
18static int usb_serial_device_match (struct device *dev, struct device_driver *drv)
19{
20	struct usb_serial_driver *driver;
21	const struct usb_serial_port *port;
22
23	/*
24	 * drivers are already assigned to ports in serial_probe so it's
25	 * a simple check here.
26	 */
27	port = to_usb_serial_port(dev);
28	if (!port)
29		return 0;
30
31	driver = to_usb_serial_driver(drv);
32
33	if (driver == port->serial->type)
34		return 1;
35
36	return 0;
37}
38
39static int usb_serial_device_probe (struct device *dev)
40{
41	struct usb_serial_driver *driver;
42	struct usb_serial_port *port;
43	int retval = 0;
44	int minor;
45
46	port = to_usb_serial_port(dev);
47	if (!port) {
48		retval = -ENODEV;
49		goto exit;
50	}
51
52	driver = port->serial->type;
53	if (driver->port_probe) {
54		if (!try_module_get(driver->driver.owner)) {
55			dev_err(dev, "module get failed, exiting\n");
56			retval = -EIO;
57			goto exit;
58		}
59		retval = driver->port_probe (port);
60		module_put(driver->driver.owner);
61		if (retval)
62			goto exit;
63	}
64
65	minor = port->number;
66	tty_register_device (usb_serial_tty_driver, minor, dev);
67	dev_info(&port->serial->dev->dev,
68		 "%s converter now attached to ttyUSB%d\n",
69		 driver->description, minor);
70
71exit:
72	return retval;
73}
74
75static int usb_serial_device_remove (struct device *dev)
76{
77	struct usb_serial_driver *driver;
78	struct usb_serial_port *port;
79	int retval = 0;
80	int minor;
81
82	port = to_usb_serial_port(dev);
83	if (!port) {
84		return -ENODEV;
85	}
86
87	driver = port->serial->type;
88	if (driver->port_remove) {
89		if (!try_module_get(driver->driver.owner)) {
90			dev_err(dev, "module get failed, exiting\n");
91			retval = -EIO;
92			goto exit;
93		}
94		retval = driver->port_remove (port);
95		module_put(driver->driver.owner);
96	}
97exit:
98	minor = port->number;
99	tty_unregister_device (usb_serial_tty_driver, minor);
100	dev_info(dev, "%s converter now disconnected from ttyUSB%d\n",
101		 driver->description, minor);
102
103	return retval;
104}
105
106#ifdef CONFIG_HOTPLUG
107static ssize_t store_new_id(struct device_driver *driver,
108			    const char *buf, size_t count)
109{
110	struct usb_serial_driver *usb_drv = to_usb_serial_driver(driver);
111	ssize_t retval = usb_store_new_id(&usb_drv->dynids, driver, buf, count);
112
113	if (retval >= 0 && usb_drv->usb_driver != NULL)
114		retval = usb_store_new_id(&usb_drv->usb_driver->dynids,
115					  &usb_drv->usb_driver->drvwrap.driver,
116					  buf, count);
117	return retval;
118}
119
120static struct driver_attribute drv_attrs[] = {
121	__ATTR(new_id, S_IWUSR, NULL, store_new_id),
122	__ATTR_NULL,
123};
124
125static void free_dynids(struct usb_serial_driver *drv)
126{
127	struct usb_dynid *dynid, *n;
128
129	spin_lock(&drv->dynids.lock);
130	list_for_each_entry_safe(dynid, n, &drv->dynids.list, node) {
131		list_del(&dynid->node);
132		kfree(dynid);
133	}
134	spin_unlock(&drv->dynids.lock);
135}
136
137#else
138static struct driver_attribute drv_attrs[] = {
139	__ATTR_NULL,
140};
141static inline void free_dynids(struct usb_driver *drv)
142{
143}
144#endif
145
146struct bus_type usb_serial_bus_type = {
147	.name =		"usb-serial",
148	.match =	usb_serial_device_match,
149	.probe =	usb_serial_device_probe,
150	.remove =	usb_serial_device_remove,
151	.drv_attrs = 	drv_attrs,
152};
153
154int usb_serial_bus_register(struct usb_serial_driver *driver)
155{
156	int retval;
157
158	driver->driver.bus = &usb_serial_bus_type;
159	spin_lock_init(&driver->dynids.lock);
160	INIT_LIST_HEAD(&driver->dynids.list);
161
162	retval = driver_register(&driver->driver);
163
164	return retval;
165}
166
167void usb_serial_bus_deregister(struct usb_serial_driver *driver)
168{
169	free_dynids(driver);
170	driver_unregister(&driver->driver);
171}
172