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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 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);
}
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