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/slab.h> 15 #include <linux/module.h> 16 #include <linux/usb.h> 17 #include <linux/usb/serial.h> 18 19 static int usb_serial_device_match(struct device *dev, 20 struct device_driver *drv) 21 { 22 struct usb_serial_driver *driver; 23 const struct usb_serial_port *port; 24 25 /* 26 * drivers are already assigned to ports in serial_probe so it's 27 * a simple check here. 28 */ 29 port = to_usb_serial_port(dev); 30 if (!port) 31 return 0; 32 33 driver = to_usb_serial_driver(drv); 34 35 if (driver == port->serial->type) 36 return 1; 37 38 return 0; 39 } 40 41 static ssize_t show_port_number(struct device *dev, 42 struct device_attribute *attr, char *buf) 43 { 44 struct usb_serial_port *port = to_usb_serial_port(dev); 45 46 return sprintf(buf, "%d\n", port->number - port->serial->minor); 47 } 48 49 static DEVICE_ATTR(port_number, S_IRUGO, show_port_number, NULL); 50 51 static int usb_serial_device_probe(struct device *dev) 52 { 53 struct usb_serial_driver *driver; 54 struct usb_serial_port *port; 55 int retval = 0; 56 int minor; 57 58 port = to_usb_serial_port(dev); 59 if (!port) { 60 retval = -ENODEV; 61 goto exit; 62 } 63 64 driver = port->serial->type; 65 if (driver->port_probe) { 66 retval = driver->port_probe(port); 67 if (retval) 68 goto exit; 69 } 70 71 retval = device_create_file(dev, &dev_attr_port_number); 72 if (retval) { 73 if (driver->port_remove) 74 retval = driver->port_remove(port); 75 goto exit; 76 } 77 78 minor = port->number; 79 tty_register_device(usb_serial_tty_driver, minor, dev); 80 dev_info(&port->serial->dev->dev, 81 "%s converter now attached to ttyUSB%d\n", 82 driver->description, minor); 83 84 exit: 85 return retval; 86 } 87 88 static int usb_serial_device_remove(struct device *dev) 89 { 90 struct usb_serial_driver *driver; 91 struct usb_serial_port *port; 92 int retval = 0; 93 int minor; 94 95 port = to_usb_serial_port(dev); 96 if (!port) 97 return -ENODEV; 98 99 device_remove_file(&port->dev, &dev_attr_port_number); 100 101 driver = port->serial->type; 102 if (driver->port_remove) 103 retval = driver->port_remove(port); 104 105 minor = port->number; 106 tty_unregister_device(usb_serial_tty_driver, minor); 107 dev_info(dev, "%s converter now disconnected from ttyUSB%d\n", 108 driver->description, minor); 109 110 return retval; 111 } 112 113 #ifdef CONFIG_HOTPLUG 114 static ssize_t store_new_id(struct device_driver *driver, 115 const char *buf, size_t count) 116 { 117 struct usb_serial_driver *usb_drv = to_usb_serial_driver(driver); 118 ssize_t retval = usb_store_new_id(&usb_drv->dynids, driver, buf, count); 119 120 if (retval >= 0 && usb_drv->usb_driver != NULL) 121 retval = usb_store_new_id(&usb_drv->usb_driver->dynids, 122 &usb_drv->usb_driver->drvwrap.driver, 123 buf, count); 124 return retval; 125 } 126 127 static ssize_t show_dynids(struct device_driver *driver, char *buf) 128 { 129 struct usb_serial_driver *usb_drv = to_usb_serial_driver(driver); 130 131 return usb_show_dynids(&usb_drv->dynids, buf); 132 } 133 134 static struct driver_attribute drv_attrs[] = { 135 __ATTR(new_id, S_IRUGO | S_IWUSR, show_dynids, store_new_id), 136 __ATTR_NULL, 137 }; 138 139 static void free_dynids(struct usb_serial_driver *drv) 140 { 141 struct usb_dynid *dynid, *n; 142 143 spin_lock(&drv->dynids.lock); 144 list_for_each_entry_safe(dynid, n, &drv->dynids.list, node) { 145 list_del(&dynid->node); 146 kfree(dynid); 147 } 148 spin_unlock(&drv->dynids.lock); 149 } 150 151 #else 152 static struct driver_attribute drv_attrs[] = { 153 __ATTR_NULL, 154 }; 155 static inline void free_dynids(struct usb_serial_driver *drv) 156 { 157 } 158 #endif 159 160 struct bus_type usb_serial_bus_type = { 161 .name = "usb-serial", 162 .match = usb_serial_device_match, 163 .probe = usb_serial_device_probe, 164 .remove = usb_serial_device_remove, 165 .drv_attrs = drv_attrs, 166 }; 167 168 int usb_serial_bus_register(struct usb_serial_driver *driver) 169 { 170 int retval; 171 172 driver->driver.bus = &usb_serial_bus_type; 173 spin_lock_init(&driver->dynids.lock); 174 INIT_LIST_HEAD(&driver->dynids.list); 175 176 retval = driver_register(&driver->driver); 177 178 return retval; 179 } 180 181 void usb_serial_bus_deregister(struct usb_serial_driver *driver) 182 { 183 free_dynids(driver); 184 driver_unregister(&driver->driver); 185 } 186 187