[PATCH 08/12] USB: serial: ftdi_sio: clean up attribute handling

From: Johan Hovold
Date: Sun Sep 11 2022 - 10:03:23 EST


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@xxxxxxxxxx>
---
drivers/usb/serial/ftdi_sio.c | 47 ++++++++++++-----------------------
1 file changed, 16 insertions(+), 31 deletions(-)

diff --git a/drivers/usb/serial/ftdi_sio.c b/drivers/usb/serial/ftdi_sio.c
index 58e0acb211df..835e12fc971a 100644
--- a/drivers/usb/serial/ftdi_sio.c
+++ b/drivers/usb/serial/ftdi_sio.c
@@ -1726,46 +1726,31 @@ 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
--
2.35.1