[linux-next] USB: serial: ftdi_sio: remove the unneeded result variable

From: Xu Panda <xu.panda@zte.com.cn>

Return the value usb_control_msg() directly instead of storing
it in another redundant variable.

Reported-by: Zeal Robot <zealci@zte.com.cn>
Signed-off-by: Xu Panda <xu.panda@zte.com.cn>
---
 drivers/usb/serial/ftdi_sio.c | 14 ++++++--------
 1 file changed, 6 insertions(+), 8 deletions(-)

On Mon, Sep 12, 2022 at 01:38:27PM +0000, cgel.zte@gmail.com wrote:
> From: Xu Panda <xu.panda@zte.com.cn>
> 
> Return the value usb_control_msg() directly instead of storing
> it in another redundant variable.
> 
> Reported-by: Zeal Robot <zealci@zte.com.cn>
> Signed-off-by: Xu Panda <xu.panda@zte.com.cn>
> ---
>  drivers/usb/serial/ftdi_sio.c | 14 ++++++--------
>  1 file changed, 6 insertions(+), 8 deletions(-)
> 
> diff --git a/drivers/usb/serial/ftdi_sio.c b/drivers/usb/serial/ftdi_sio.c
> index 0a1da579ead5..f02dcef69cb9 100644
> --- a/drivers/usb/serial/ftdi_sio.c
> +++ b/drivers/usb/serial/ftdi_sio.c
> @@ -1394,7 +1394,6 @@ static int change_speed(struct tty_struct *tty, struct usb_serial_port *port)
>         u16 value;
>         u16 index;
>         u32 index_value;
> -       int rv;
> 
>         index_value = get_ftdi_divisor(tty, port);
>         value = (u16)index_value;
> @@ -1407,13 +1406,12 @@ static int change_speed(struct tty_struct *tty, struct usb_serial_port *port)
>                 index = (u16)((index << 8) | priv->interface);
>         }
> 
> -       rv = usb_control_msg(port->serial->dev,
> -                           usb_sndctrlpipe(port->serial->dev, 0),
> -                           FTDI_SIO_SET_BAUDRATE_REQUEST,
> -                           FTDI_SIO_SET_BAUDRATE_REQUEST_TYPE,
> -                           value, index,
> -                           NULL, 0, WDR_SHORT_TIMEOUT);
> -       return rv;
> +       return usb_control_msg(port->serial->dev,
> +                              usb_sndctrlpipe(port->serial->dev, 0),
> +                              FTDI_SIO_SET_BAUDRATE_REQUEST,
> +                              FTDI_SIO_SET_BAUDRATE_REQUEST_TYPE,
> +                              value, index,
> +                              NULL, 0, WDR_SHORT_TIMEOUT);
>  }

That's really not the correct use of the return value of
usb_control_msg().  Can you fix this up to properly handle the return
value, or better yet, use the usb_control_msg_send() call?

thanks,

greg k-h

On Mon, Sep 12, 2022 at 04:05:39PM +0200, Greg Kroah-Hartman wrote:
> On Mon, Sep 12, 2022 at 01:38:27PM +0000, cgel.zte@gmail.com wrote:
> > From: Xu Panda <xu.panda@zte.com.cn>
> > 
> > Return the value usb_control_msg() directly instead of storing
> > it in another redundant variable.
> > 
> > Reported-by: Zeal Robot <zealci@zte.com.cn>
> > Signed-off-by: Xu Panda <xu.panda@zte.com.cn>

> > -       rv = usb_control_msg(port->serial->dev,
> > -                           usb_sndctrlpipe(port->serial->dev, 0),
> > -                           FTDI_SIO_SET_BAUDRATE_REQUEST,
> > -                           FTDI_SIO_SET_BAUDRATE_REQUEST_TYPE,
> > -                           value, index,
> > -                           NULL, 0, WDR_SHORT_TIMEOUT);
> > -       return rv;
> > +       return usb_control_msg(port->serial->dev,
> > +                              usb_sndctrlpipe(port->serial->dev, 0),
> > +                              FTDI_SIO_SET_BAUDRATE_REQUEST,
> > +                              FTDI_SIO_SET_BAUDRATE_REQUEST_TYPE,
> > +                              value, index,
> > +                              NULL, 0, WDR_SHORT_TIMEOUT);
> >  }
> 
> That's really not the correct use of the return value of
> usb_control_msg().  Can you fix this up to properly handle the return
> value, or better yet, use the usb_control_msg_send() call?

It is actually correct since the buffer length is zero here (i.e. it
returns a negative errno or 0).

But I'm also ignoring patches from this email address as it is used by
multiple users, and of which none so far has replied to feedback (as if
it's all automated).

Johan