diff options
-rw-r--r-- | drivers/usb/serial/bus.c | 16 |
1 files changed, 16 insertions, 0 deletions
diff --git a/drivers/usb/serial/bus.c b/drivers/usb/serial/bus.c index a47a24f8820..0b14aea8ebd 100644 --- a/drivers/usb/serial/bus.c +++ b/drivers/usb/serial/bus.c @@ -36,6 +36,16 @@ static int usb_serial_device_match (struct device *dev, struct device_driver *dr 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; @@ -62,6 +72,10 @@ static int usb_serial_device_probe (struct device *dev) goto exit; } + retval = device_create_file(dev, &dev_attr_port_number); + if (retval) + goto exit; + minor = port->number; tty_register_device (usb_serial_tty_driver, minor, dev); dev_info(&port->serial->dev->dev, @@ -84,6 +98,8 @@ static int usb_serial_device_remove (struct device *dev) return -ENODEV; } + device_remove_file(&port->dev, &dev_attr_port_number); + driver = port->serial->type; if (driver->port_remove) { if (!try_module_get(driver->driver.owner)) { |