1// SPDX-License-Identifier: GPL-2.0 2/* 3 * USB Serial Converter Bus specific functions 4 * 5 * Copyright (C) 2002 Greg Kroah-Hartman (greg@kroah.com) 6 */ 7 8#include <linux/kernel.h> 9#include <linux/errno.h> 10#include <linux/tty.h> 11#include <linux/slab.h> 12#include <linux/module.h> 13#include <linux/usb.h> 14#include <linux/usb/serial.h> 15 16static int usb_serial_device_match(struct device *dev, 17 struct device_driver *drv) 18{ 19 struct usb_serial_driver *driver; 20 const struct usb_serial_port *port; 21 22 /* 23 * drivers are already assigned to ports in serial_probe so it's 24 * a simple check here. 25 */ 26 port = to_usb_serial_port(dev); 27 if (!port) 28 return 0; 29 30 driver = to_usb_serial_driver(drv); 31 32 if (driver == port->serial->type) 33 return 1; 34 35 return 0; 36} 37 38static int usb_serial_device_probe(struct device *dev) 39{ 40 struct usb_serial_driver *driver; 41 struct usb_serial_port *port; 42 struct device *tty_dev; 43 int retval = 0; 44 int minor; 45 46 port = to_usb_serial_port(dev); 47 if (!port) 48 return -ENODEV; 49 50 /* make sure suspend/resume doesn't race against port_probe */ 51 retval = usb_autopm_get_interface(port->serial->interface); 52 if (retval) 53 return retval; 54 55 driver = port->serial->type; 56 if (driver->port_probe) { 57 retval = driver->port_probe(port); 58 if (retval) 59 goto err_autopm_put; 60 } 61 62 minor = port->minor; 63 tty_dev = tty_port_register_device(&port->port, usb_serial_tty_driver, 64 minor, dev); 65 if (IS_ERR(tty_dev)) { 66 retval = PTR_ERR(tty_dev); 67 goto err_port_remove; 68 } 69 70 usb_autopm_put_interface(port->serial->interface); 71 72 dev_info(&port->serial->dev->dev, 73 "%s converter now attached to ttyUSB%d\n", 74 driver->description, minor); 75 76 return 0; 77 78err_port_remove: 79 if (driver->port_remove) 80 driver->port_remove(port); 81err_autopm_put: 82 usb_autopm_put_interface(port->serial->interface); 83 84 return retval; 85} 86 87static int usb_serial_device_remove(struct device *dev) 88{ 89 struct usb_serial_driver *driver; 90 struct usb_serial_port *port; 91 int retval = 0; 92 int minor; 93 int autopm_err; 94 95 port = to_usb_serial_port(dev); 96 if (!port) 97 return -ENODEV; 98 99 /* 100 * Make sure suspend/resume doesn't race against port_remove. 101 * 102 * Note that no further runtime PM callbacks will be made if 103 * autopm_get fails. 104 */ 105 autopm_err = usb_autopm_get_interface(port->serial->interface); 106 107 minor = port->minor; 108 tty_unregister_device(usb_serial_tty_driver, minor); 109 110 driver = port->serial->type; 111 if (driver->port_remove) 112 retval = driver->port_remove(port); 113 114 dev_info(dev, "%s converter now disconnected from ttyUSB%d\n", 115 driver->description, minor); 116 117 if (!autopm_err) 118 usb_autopm_put_interface(port->serial->interface); 119 120 return retval; 121} 122 123static ssize_t new_id_store(struct device_driver *driver, 124 const char *buf, size_t count) 125{ 126 struct usb_serial_driver *usb_drv = to_usb_serial_driver(driver); 127 ssize_t retval = usb_store_new_id(&usb_drv->dynids, usb_drv->id_table, 128 driver, buf, count); 129 130 if (retval >= 0 && usb_drv->usb_driver != NULL) 131 retval = usb_store_new_id(&usb_drv->usb_driver->dynids, 132 usb_drv->usb_driver->id_table, 133 &usb_drv->usb_driver->drvwrap.driver, 134 buf, count); 135 return retval; 136} 137 138static ssize_t new_id_show(struct device_driver *driver, char *buf) 139{ 140 struct usb_serial_driver *usb_drv = to_usb_serial_driver(driver); 141 142 return usb_show_dynids(&usb_drv->dynids, buf); 143} 144static DRIVER_ATTR_RW(new_id); 145 146static struct attribute *usb_serial_drv_attrs[] = { 147 &driver_attr_new_id.attr, 148 NULL, 149}; 150ATTRIBUTE_GROUPS(usb_serial_drv); 151 152static void free_dynids(struct usb_serial_driver *drv) 153{ 154 struct usb_dynid *dynid, *n; 155 156 spin_lock(&drv->dynids.lock); 157 list_for_each_entry_safe(dynid, n, &drv->dynids.list, node) { 158 list_del(&dynid->node); 159 kfree(dynid); 160 } 161 spin_unlock(&drv->dynids.lock); 162} 163 164struct bus_type usb_serial_bus_type = { 165 .name = "usb-serial", 166 .match = usb_serial_device_match, 167 .probe = usb_serial_device_probe, 168 .remove = usb_serial_device_remove, 169 .drv_groups = usb_serial_drv_groups, 170}; 171 172int usb_serial_bus_register(struct usb_serial_driver *driver) 173{ 174 int retval; 175 176 driver->driver.bus = &usb_serial_bus_type; 177 spin_lock_init(&driver->dynids.lock); 178 INIT_LIST_HEAD(&driver->dynids.list); 179 180 retval = driver_register(&driver->driver); 181 182 return retval; 183} 184 185void usb_serial_bus_deregister(struct usb_serial_driver *driver) 186{ 187 free_dynids(driver); 188 driver_unregister(&driver->driver); 189} 190 191