USB: serial: ftdi_sio: clean up attribute handling

The driver exposes two attributes for all chip types but FT232A, which
doesn't have a configurable latency timer, and SIO, which (probably)
doesn't support the event-char mechanism either.

Explicitly test for the exceptions rather than list each and every
supported device type in the attribute helpers.

Signed-off-by: Johan Hovold <johan@kernel.org>

diff --git a/drivers/usb/serial/ftdi_sio.c b/drivers/usb/serial/ftdi_sio.c
index eecd4b13a5ec43f7ece65a5eaf94051cb8da6bec..05c635e3cb30473c05dcffae8ecc23255b2e9ca2 100644 (file)
--- a/drivers/usb/serial/ftdi_sio.c
+++ b/drivers/usb/serial/ftdi_sio.c
@@ -1725,46 +1725,31 @@ static DEVICE_ATTR_WO(event_char);
 static int create_sysfs_attrs(struct usb_serial_port *port)
 {
        struct ftdi_private *priv = usb_get_serial_port_data(port);
-       int retval = 0;
-
-       /* XXX I've no idea if the original SIO supports the event_char
-        * sysfs parameter, so I'm playing it safe.  */
-       if (priv->chip_type != SIO) {
-               dev_dbg(&port->dev, "sysfs attributes for %s\n", ftdi_chip_name[priv->chip_type]);
-               retval = device_create_file(&port->dev, &dev_attr_event_char);
-               if ((!retval) &&
-                   (priv->chip_type == FT232B ||
-                    priv->chip_type == FT2232C ||
-                    priv->chip_type == FT232R ||
-                    priv->chip_type == FT2232H ||
-                    priv->chip_type == FT4232H ||
-                    priv->chip_type == FT232H ||
-                    priv->chip_type == FTX)) {
-                       retval = device_create_file(&port->dev,
-                                                   &dev_attr_latency_timer);
-               }
+       enum ftdi_chip_type type = priv->chip_type;
+       int ret = 0;
+
+       if (type != SIO) {
+               ret = device_create_file(&port->dev, &dev_attr_event_char);
+               if (ret)
+                       return ret;
        }
-       return retval;
+
+       if (type != SIO && type != FT232A)
+               ret = device_create_file(&port->dev, &dev_attr_latency_timer);
+
+       return ret;
 }
 
 static void remove_sysfs_attrs(struct usb_serial_port *port)
 {
        struct ftdi_private *priv = usb_get_serial_port_data(port);
+       enum ftdi_chip_type type = priv->chip_type;
 
-       /* XXX see create_sysfs_attrs */
-       if (priv->chip_type != SIO) {
+       if (type != SIO)
                device_remove_file(&port->dev, &dev_attr_event_char);
-               if (priv->chip_type == FT232B ||
-                   priv->chip_type == FT2232C ||
-                   priv->chip_type == FT232R ||
-                   priv->chip_type == FT2232H ||
-                   priv->chip_type == FT4232H ||
-                   priv->chip_type == FT232H ||
-                   priv->chip_type == FTX) {
-                       device_remove_file(&port->dev, &dev_attr_latency_timer);
-               }
-       }
 
+       if (type != SIO && type != FT232A)
+               device_remove_file(&port->dev, &dev_attr_latency_timer);
 }
 
 #ifdef CONFIG_GPIOLIB