Re: [PATCH 1/11] USB: kl5kusb105: Remove useless return variables

From: Johan Hovold
Date: Sat May 31 2014 - 10:58:46 EST


On Sat, May 31, 2014 at 10:14:01AM -0300, Peter Senna Tschudin wrote:
> This patch remove variables that are initialized with a constant,
> are never updated, and are only used as parameter of return.
> Return the constant instead of using a variable.
>
> Verified by compilation only.
>
> The coccinelle script that find and fixes this issue is:
> // <smpl>
> @@
> type T;
> constant C;
> identifier ret;
> @@
> - T ret = C;
> ... when != ret
> when strict
> return
> - ret
> + C
> ;
> // </smpl>
>
> Signed-off-by: Peter Senna Tschudin <peter.senna@xxxxxxxxx>
>
> ---
> drivers/usb/serial/kl5kusb105.c | 23 +----------------------
> 1 file changed, 1 insertion(+), 22 deletions(-)
>
> diff --git a/drivers/usb/serial/kl5kusb105.c b/drivers/usb/serial/kl5kusb105.c
> index d7440b7..2657c00 100644
> --- a/drivers/usb/serial/kl5kusb105.c
> +++ b/drivers/usb/serial/kl5kusb105.c
> @@ -605,28 +605,7 @@ static int klsi_105_tiocmget(struct tty_struct *tty)
> static int klsi_105_tiocmset(struct tty_struct *tty,
> unsigned int set, unsigned int clear)
> {
> - int retval = -EINVAL;
> -
> -/* if this ever gets implemented, it should be done something like this:
> - struct usb_serial *serial = port->serial;
> - struct klsi_105_private *priv = usb_get_serial_port_data(port);
> - unsigned long flags;
> - int control;
> -
> - spin_lock_irqsave (&priv->lock, flags);
> - if (set & TIOCM_RTS)
> - priv->control_state |= TIOCM_RTS;
> - if (set & TIOCM_DTR)
> - priv->control_state |= TIOCM_DTR;
> - if (clear & TIOCM_RTS)
> - priv->control_state &= ~TIOCM_RTS;
> - if (clear & TIOCM_DTR)
> - priv->control_state &= ~TIOCM_DTR;
> - control = priv->control_state;
> - spin_unlock_irqrestore (&priv->lock, flags);
> - retval = mct_u232_set_modem_ctrl(serial, control);
> -*/
> - return retval;
> + return -EINVAL;

Your patch does a bit more than what the description says, although
removing this out-commented code would be perfectly fine.

But please just remove the entire function (and the corresponding entry
in the struct usb_serial_driver) and update the commit message.

Thanks,
Johan

> }
>
> module_usb_serial_driver(serial_drivers, id_table);
>
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