TIOCSSERIAL is a horrid, underspecified, legacy interface which for most serial devices is only useful for setting the close_delay and closing_wait parameters.
A non-privileged user has only ever been able to set the since long deprecated ASYNC_SPD flags and trying to change any other *supported* feature should result in -EPERM being returned. Setting the current values for any supported features should return success. Fix the fwserial implementation which was returning -EPERM also for a privileged user when trying to change certain unsupported parameters, and instead return success consistently. Fixes: 7355ba3445f2 ("staging: fwserial: Add TTY-over-Firewire serial driver") Signed-off-by: Johan Hovold <jo...@kernel.org> --- drivers/staging/fwserial/fwserial.c | 4 ---- 1 file changed, 4 deletions(-) diff --git a/drivers/staging/fwserial/fwserial.c b/drivers/staging/fwserial/fwserial.c index 440d11423812..2888b80a2c1a 100644 --- a/drivers/staging/fwserial/fwserial.c +++ b/drivers/staging/fwserial/fwserial.c @@ -1234,10 +1234,6 @@ static int set_serial_info(struct tty_struct *tty, struct fwtty_port *port = tty->driver_data; unsigned int cdelay; - if (ss->irq != 0 || ss->port != 0 || ss->custom_divisor != 0 || - ss->baud_base != 400000000) - return -EPERM; - cdelay = msecs_to_jiffies(ss->close_delay * 10); mutex_lock(&port->port.mutex); -- 2.26.3