diff options
Diffstat (limited to 'drivers/usb/serial/bus.c')
| -rw-r--r-- | drivers/usb/serial/bus.c | 179 |
1 files changed, 179 insertions, 0 deletions
diff --git a/drivers/usb/serial/bus.c b/drivers/usb/serial/bus.c new file mode 100644 index 00000000..ed8adb05 --- /dev/null +++ b/drivers/usb/serial/bus.c @@ -0,0 +1,179 @@ +/* + * USB Serial Converter Bus specific functions + * + * Copyright (C) 2002 Greg Kroah-Hartman (greg@kroah.com) + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License version + * 2 as published by the Free Software Foundation. + */ + +#include <linux/kernel.h> +#include <linux/errno.h> +#include <linux/tty.h> +#include <linux/slab.h> +#include <linux/module.h> +#include <linux/usb.h> +#include <linux/usb/serial.h> + +static int usb_serial_device_match(struct device *dev, + struct device_driver *drv) +{ + struct usb_serial_driver *driver; + const struct usb_serial_port *port; + + /* + * drivers are already assigned to ports in serial_probe so it's + * a simple check here. + */ + port = to_usb_serial_port(dev); + if (!port) + return 0; + + driver = to_usb_serial_driver(drv); + + if (driver == port->serial->type) + return 1; + + return 0; +} + +static ssize_t show_port_number(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct usb_serial_port *port = to_usb_serial_port(dev); + + return sprintf(buf, "%d\n", port->number - port->serial->minor); +} + +static DEVICE_ATTR(port_number, S_IRUGO, show_port_number, NULL); + +static int usb_serial_device_probe(struct device *dev) +{ + struct usb_serial_driver *driver; + struct usb_serial_port *port; + int retval = 0; + int minor; + + port = to_usb_serial_port(dev); + if (!port) { + retval = -ENODEV; + goto exit; + } + + driver = port->serial->type; + if (driver->port_probe) { + retval = driver->port_probe(port); + if (retval) + goto exit; + } + + retval = device_create_file(dev, &dev_attr_port_number); + if (retval) { + if (driver->port_remove) + retval = driver->port_remove(port); + goto exit; + } + + minor = port->number; + tty_register_device(usb_serial_tty_driver, minor, dev); + dev_info(&port->serial->dev->dev, + "%s converter now attached to ttyUSB%d\n", + driver->description, minor); + +exit: + return retval; +} + +static int usb_serial_device_remove(struct device *dev) +{ + struct usb_serial_driver *driver; + struct usb_serial_port *port; + int retval = 0; + int minor; + + port = to_usb_serial_port(dev); + if (!port) + return -ENODEV; + + device_remove_file(&port->dev, &dev_attr_port_number); + + driver = port->serial->type; + if (driver->port_remove) + retval = driver->port_remove(port); + + minor = port->number; + tty_unregister_device(usb_serial_tty_driver, minor); + dev_info(dev, "%s converter now disconnected from ttyUSB%d\n", + driver->description, minor); + + return retval; +} + +#ifdef CONFIG_HOTPLUG +static ssize_t store_new_id(struct device_driver *driver, + const char *buf, size_t count) +{ + struct usb_serial_driver *usb_drv = to_usb_serial_driver(driver); + ssize_t retval = usb_store_new_id(&usb_drv->dynids, driver, buf, count); + + if (retval >= 0 && usb_drv->usb_driver != NULL) + retval = usb_store_new_id(&usb_drv->usb_driver->dynids, + &usb_drv->usb_driver->drvwrap.driver, + buf, count); + return retval; +} + +static struct driver_attribute drv_attrs[] = { + __ATTR(new_id, S_IWUSR, NULL, store_new_id), + __ATTR_NULL, +}; + +static void free_dynids(struct usb_serial_driver *drv) +{ + struct usb_dynid *dynid, *n; + + spin_lock(&drv->dynids.lock); + list_for_each_entry_safe(dynid, n, &drv->dynids.list, node) { + list_del(&dynid->node); + kfree(dynid); + } + spin_unlock(&drv->dynids.lock); +} + +#else +static struct driver_attribute drv_attrs[] = { + __ATTR_NULL, +}; +static inline void free_dynids(struct usb_serial_driver *drv) +{ +} +#endif + +struct bus_type usb_serial_bus_type = { + .name = "usb-serial", + .match = usb_serial_device_match, + .probe = usb_serial_device_probe, + .remove = usb_serial_device_remove, + .drv_attrs = drv_attrs, +}; + +int usb_serial_bus_register(struct usb_serial_driver *driver) +{ + int retval; + + driver->driver.bus = &usb_serial_bus_type; + spin_lock_init(&driver->dynids.lock); + INIT_LIST_HEAD(&driver->dynids.list); + + retval = driver_register(&driver->driver); + + return retval; +} + +void usb_serial_bus_deregister(struct usb_serial_driver *driver) +{ + free_dynids(driver); + driver_unregister(&driver->driver); +} + |