diff options
| author | Alan Cox <alan@linux.intel.com> | 2009-10-28 21:12:32 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2009-11-17 16:42:28 -0800 |
| commit | 4175f3e31cc7157669aa66d46dc79de6ae0126ce (patch) | |
| tree | de3c0ff054f3c403c5354b23c52f3e8e5e7c5510 /drivers/char/tty_port.c | |
| parent | ac50e950784cae1c26ad9e09ebd8f8c706131eb3 (diff) | |
| download | lwn-4175f3e31cc7157669aa66d46dc79de6ae0126ce.tar.gz lwn-4175f3e31cc7157669aa66d46dc79de6ae0126ce.zip | |
tty_port: If we are opened non blocking we still need to raise the carrier
Original discussion:
http://thread.gmane.org/gmane.linux.usb.general/23217/focus=23248
or
http://marc.info/?l=linux-usb&m=125553790714133&w=2
The tty_port code inherited a bug common to various drivers it was based
upon. If the tty is opened O_NONBLOCK we do not wait for the carrier to be
raised but we must still raise our modem lines if appropriate.
(There is a second question here about whether we should do so if CLOCAL is
set but that can wait)
Signed-off-by: Alan Cox <alan@linux.intel.com>
Reported-by: Karl Hiramoto <karl@hiramoto.org>
Tested-by: Karl Hiramoto <karl@hiramoto.org>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'drivers/char/tty_port.c')
| -rw-r--r-- | drivers/char/tty_port.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/drivers/char/tty_port.c b/drivers/char/tty_port.c index a4bbb28f10be..2e8552dc5eda 100644 --- a/drivers/char/tty_port.c +++ b/drivers/char/tty_port.c @@ -221,6 +221,9 @@ int tty_port_block_til_ready(struct tty_port *port, the port has just hung up or is in another error state */ if ((filp->f_flags & O_NONBLOCK) || (tty->flags & (1 << TTY_IO_ERROR))) { + /* Indicate we are open */ + if (tty->termios->c_cflag & CBAUD) + tty_port_raise_dtr_rts(port); port->flags |= ASYNC_NORMAL_ACTIVE; return 0; } |