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 if (port->dev_state != PORT_REGISTERING) 64 goto exit; 65 66 driver = port->serial->type; 67 if (driver->port_probe) { 68 retval = driver->port_probe(port); 69 if (retval) 70 goto exit; 71 } 72 73 retval = device_create_file(dev, &dev_attr_port_number); 74 if (retval) { 75 if (driver->port_remove) 76 retval = driver->port_remove(port); 77 goto exit; 78 } 79 80 minor = port->number; 81 tty_register_device(usb_serial_tty_driver, minor, dev); 82 dev_info(&port->serial->dev->dev, 83 "%s converter now attached to ttyUSB%d\n", 84 driver->description, minor); 85 86 exit: 87 return retval; 88 } 89 90 static int usb_serial_device_remove(struct device *dev) 91 { 92 struct usb_serial_driver *driver; 93 struct usb_serial_port *port; 94 int retval = 0; 95 int minor; 96 97 port = to_usb_serial_port(dev); 98 if (!port) 99 return -ENODEV; 100 101 if (port->dev_state != PORT_UNREGISTERING) 102 return retval; 103 104 device_remove_file(&port->dev, &dev_attr_port_number); 105 106 driver = port->serial->type; 107 if (driver->port_remove) 108 retval = driver->port_remove(port); 109 110 minor = port->number; 111 tty_unregister_device(usb_serial_tty_driver, minor); 112 dev_info(dev, "%s converter now disconnected from ttyUSB%d\n", 113 driver->description, minor); 114 115 return retval; 116 } 117 118 #ifdef CONFIG_HOTPLUG 119 static ssize_t store_new_id(struct device_driver *driver, 120 const char *buf, size_t count) 121 { 122 struct usb_serial_driver *usb_drv = to_usb_serial_driver(driver); 123 ssize_t retval = usb_store_new_id(&usb_drv->dynids, driver, buf, count); 124 125 if (retval >= 0 && usb_drv->usb_driver != NULL) 126 retval = usb_store_new_id(&usb_drv->usb_driver->dynids, 127 &usb_drv->usb_driver->drvwrap.driver, 128 buf, count); 129 return retval; 130 } 131 132 static struct driver_attribute drv_attrs[] = { 133 __ATTR(new_id, S_IWUSR, NULL, store_new_id), 134 __ATTR_NULL, 135 }; 136 137 static void free_dynids(struct usb_serial_driver *drv) 138 { 139 struct usb_dynid *dynid, *n; 140 141 spin_lock(&drv->dynids.lock); 142 list_for_each_entry_safe(dynid, n, &drv->dynids.list, node) { 143 list_del(&dynid->node); 144 kfree(dynid); 145 } 146 spin_unlock(&drv->dynids.lock); 147 } 148 149 #else 150 static struct driver_attribute drv_attrs[] = { 151 __ATTR_NULL, 152 }; 153 static inline void free_dynids(struct usb_serial_driver *drv) 154 { 155 } 156 #endif 157 158 struct bus_type usb_serial_bus_type = { 159 .name = "usb-serial", 160 .match = usb_serial_device_match, 161 .probe = usb_serial_device_probe, 162 .remove = usb_serial_device_remove, 163 .drv_attrs = drv_attrs, 164 }; 165 166 int usb_serial_bus_register(struct usb_serial_driver *driver) 167 { 168 int retval; 169 170 driver->driver.bus = &usb_serial_bus_type; 171 spin_lock_init(&driver->dynids.lock); 172 INIT_LIST_HEAD(&driver->dynids.list); 173 174 retval = driver_register(&driver->driver); 175 176 return retval; 177 } 178 179 void usb_serial_bus_deregister(struct usb_serial_driver *driver) 180 { 181 free_dynids(driver); 182 driver_unregister(&driver->driver); 183 } 184 185