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 /* make sure suspend/resume doesn't race against port_probe */ 65 retval = usb_autopm_get_interface(port->serial->interface); 66 if (retval) 67 goto exit; 68 69 driver = port->serial->type; 70 if (driver->port_probe) { 71 retval = driver->port_probe(port); 72 if (retval) 73 goto exit_with_autopm; 74 } 75 76 retval = device_create_file(dev, &dev_attr_port_number); 77 if (retval) { 78 if (driver->port_remove) 79 retval = driver->port_remove(port); 80 goto exit_with_autopm; 81 } 82 83 minor = port->number; 84 tty_register_device(usb_serial_tty_driver, minor, dev); 85 dev_info(&port->serial->dev->dev, 86 "%s converter now attached to ttyUSB%d\n", 87 driver->description, minor); 88 89 exit_with_autopm: 90 usb_autopm_put_interface(port->serial->interface); 91 exit: 92 return retval; 93 } 94 95 static int usb_serial_device_remove(struct device *dev) 96 { 97 struct usb_serial_driver *driver; 98 struct usb_serial_port *port; 99 int retval = 0; 100 int minor; 101 102 port = to_usb_serial_port(dev); 103 if (!port) 104 return -ENODEV; 105 106 /* make sure suspend/resume doesn't race against port_remove */ 107 usb_autopm_get_interface(port->serial->interface); 108 109 device_remove_file(&port->dev, &dev_attr_port_number); 110 111 driver = port->serial->type; 112 if (driver->port_remove) 113 retval = driver->port_remove(port); 114 115 minor = port->number; 116 tty_unregister_device(usb_serial_tty_driver, minor); 117 dev_info(dev, "%s converter now disconnected from ttyUSB%d\n", 118 driver->description, minor); 119 120 usb_autopm_put_interface(port->serial->interface); 121 return retval; 122 } 123 124 static ssize_t store_new_id(struct device_driver *driver, 125 const char *buf, size_t count) 126 { 127 struct usb_serial_driver *usb_drv = to_usb_serial_driver(driver); 128 ssize_t retval = usb_store_new_id(&usb_drv->dynids, 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->drvwrap.driver, 133 buf, count); 134 return retval; 135 } 136 137 static ssize_t show_dynids(struct device_driver *driver, char *buf) 138 { 139 struct usb_serial_driver *usb_drv = to_usb_serial_driver(driver); 140 141 return usb_show_dynids(&usb_drv->dynids, buf); 142 } 143 144 static struct driver_attribute drv_attrs[] = { 145 __ATTR(new_id, S_IRUGO | S_IWUSR, show_dynids, store_new_id), 146 __ATTR_NULL, 147 }; 148 149 static void free_dynids(struct usb_serial_driver *drv) 150 { 151 struct usb_dynid *dynid, *n; 152 153 spin_lock(&drv->dynids.lock); 154 list_for_each_entry_safe(dynid, n, &drv->dynids.list, node) { 155 list_del(&dynid->node); 156 kfree(dynid); 157 } 158 spin_unlock(&drv->dynids.lock); 159 } 160 161 struct bus_type usb_serial_bus_type = { 162 .name = "usb-serial", 163 .match = usb_serial_device_match, 164 .probe = usb_serial_device_probe, 165 .remove = usb_serial_device_remove, 166 .drv_attrs = drv_attrs, 167 }; 168 169 int usb_serial_bus_register(struct usb_serial_driver *driver) 170 { 171 int retval; 172 173 driver->driver.bus = &usb_serial_bus_type; 174 spin_lock_init(&driver->dynids.lock); 175 INIT_LIST_HEAD(&driver->dynids.list); 176 177 retval = driver_register(&driver->driver); 178 179 return retval; 180 } 181 182 void usb_serial_bus_deregister(struct usb_serial_driver *driver) 183 { 184 free_dynids(driver); 185 driver_unregister(&driver->driver); 186 } 187 188