From 63443a0b2ab277ef677640bc32b4f94661821b70 Mon Sep 17 00:00:00 2001 From: Mikhail Zaytsev Date: Sat, 6 Jan 2018 20:14:02 +0300 Subject: USB: serial: ark3116: remove dummy TIOCSSERIAL ioctl The patch removes unused TIOCSSERIAL ioctl case and adds the default block to the switch. This will make the ioctl return -ENOTTY to user space (e.g. setserial), which indicates that TIOCSSERIAL really isn't supported for these devices currently. Note that these (dummy) ioctl implementations where added by commit 2f430b4bbae7 ("USB: ark3116: Add TIOCGSERIAL and TIOCSSERIAL ioctl calls.") back in 2006. This in turn appears to have been triggered by a change in a user space tool, wvdial, which started erroring out if either was missing. There are some bug reports about that against wvdial from around that time, and looking at the wvstreams (library) code now, it looks like the issue has indeed been resolved by handling errors more gracefully (e.g. just logging them). User space really should not make assumptions about these ioctl always being implemented, but if this turns out to be a problem for anyone using this driver, we'll add TIOCSSERIAL back in some form. Signed-off-by: Mikhail Zaytsev [johan: amend commit message with backstory ] Signed-off-by: Johan Hovold --- drivers/usb/serial/ark3116.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) (limited to 'drivers/usb/serial') diff --git a/drivers/usb/serial/ark3116.c b/drivers/usb/serial/ark3116.c index 23d46ef..2e957c7 100644 --- a/drivers/usb/serial/ark3116.c +++ b/drivers/usb/serial/ark3116.c @@ -418,10 +418,8 @@ static int ark3116_ioctl(struct tty_struct *tty, return -EFAULT; return 0; - case TIOCSSERIAL: - if (copy_from_user(&serstruct, user_arg, sizeof(serstruct))) - return -EFAULT; - return 0; + default: + break; } return -ENOIOCTLCMD; -- cgit v1.1