// SPDX-License-Identifier: GPL-2.0/* * USB Serial Converter Bus specific functions * * Copyright (C) 2002 Greg Kroah-Hartman (greg@kroah.com) */ #include <linux/kernel.h>#include <linux/errno.h>#include <linux/tty.h>#include <linux/slab.h>#include <linux/module.h>#include <linux/usb.h>#include <linux/usb/serial.h> static int usb_serial_device_match(struct device *dev,				   const struct device_driver *drv){	const struct usb_serial_port *port = to_usb_serial_port(dev);	const struct usb_serial_driver *driver = to_usb_serial_driver(drv); 	/*	 * drivers are already assigned to ports in serial_probe so it's	 * a simple check here.	 */	if (driver == port->serial->type)		return 1; 	return 0;} static int usb_serial_device_probe(struct device *dev){	struct usb_serial_port *port = to_usb_serial_port(dev);	struct usb_serial_driver *driver;	struct device *tty_dev;	int retval = 0;	int minor; 	/* make sure suspend/resume doesn't race against port_probe */	retval = usb_autopm_get_interface(port->serial->interface);	if (retval)		return retval; 	driver = port->serial->type;	if (driver->port_probe) {		retval = driver->port_probe(port);		if (retval)			goto err_autopm_put;	} 	minor = port->minor;	tty_dev = tty_port_register_device(&port->port, usb_serial_tty_driver,					   minor, dev);	if (IS_ERR(tty_dev)) {		retval = PTR_ERR(tty_dev);		goto err_port_remove;	} 	usb_autopm_put_interface(port->serial->interface); 	dev_info(&port->serial->dev->dev,		 "%s converter now attached to ttyUSB%d\n",		 driver->description, minor); 	return 0; err_port_remove:	if (driver->port_remove)		driver->port_remove(port);err_autopm_put:	usb_autopm_put_interface(port->serial->interface); 	return retval;} static void usb_serial_device_remove(struct device *dev){	struct usb_serial_port *port = to_usb_serial_port(dev);	struct usb_serial_driver *driver;	int minor;	int autopm_err; 	/*	 * Make sure suspend/resume doesn't race against port_remove.	 *	 * Note that no further runtime PM callbacks will be made if	 * autopm_get fails.	 */	autopm_err = usb_autopm_get_interface(port->serial->interface); 	minor = port->minor;	tty_unregister_device(usb_serial_tty_driver, minor); 	driver = port->serial->type;	if (driver->port_remove)		driver->port_remove(port); 	dev_info(dev, "%s converter now disconnected from ttyUSB%d\n",		 driver->description, minor); 	if (!autopm_err)		usb_autopm_put_interface(port->serial->interface);} static ssize_t new_id_store(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, usb_drv->id_table,					 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->id_table,					  &usb_drv->usb_driver->driver,					  buf, count);	return retval;} static ssize_t new_id_show(struct device_driver *driver, char *buf){	struct usb_serial_driver *usb_drv = to_usb_serial_driver(driver); 	return usb_show_dynids(&usb_drv->dynids, buf);}static DRIVER_ATTR_RW(new_id); static struct attribute *usb_serial_drv_attrs[] = {	&driver_attr_new_id.attr,	NULL,};ATTRIBUTE_GROUPS(usb_serial_drv); static void free_dynids(struct usb_serial_driver *drv){	struct usb_dynid *dynid, *n; 	guard(mutex)(&usb_dynids_lock);	list_for_each_entry_safe(dynid, n, &drv->dynids.list, node) {		list_del(&dynid->node);		kfree(dynid);	}} const 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_groups = 	usb_serial_drv_groups,}; int usb_serial_bus_register(struct usb_serial_driver *driver){	int retval; 	driver->driver.bus = &usb_serial_bus_type;	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);}