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