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/*
* 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 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;
}
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;
}
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;
}
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,
};
int usb_serial_bus_register(struct usb_serial_driver *driver)
{
int retval;
driver->driver.bus = &usb_serial_bus_type;
retval = driver_register(&driver->driver);
return retval;
}
void usb_serial_bus_deregister(struct usb_serial_driver *driver)
{
driver_unregister(&driver->driver);
}
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