The new dtr_rts function didn't take the port->func lock as it should
so add use of the lock there.
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Add the POSIX block for carrier
Linux TIOCMIWAIT functionality is still lacking from the driver.
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Running the current code through checkpatch shows a few bits of noise
mostly but not entirely from before the changes.
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Switching between two non standard baud rates fails because of the cflag
test. Do as we did elsewhere and just kill the "optimisation".
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Gets us proper tty semantics, removes some code and fixes up a few corner
case races (hangup during open etc)
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
When we move to the tty_port logic the port mutex will protect open v close
v hangup. Move to this first in the existing open code so we have a bisection
point.
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The tty can go away underneath us, so we must refcount it. Do the naïve
implementation initially. We will worry about startup shortly.
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Now... testing reveals that the very first patch "sdio_uart: use
tty_port" causes a segmentation fault in sdio_uart_open():
Unable to handle kernel NULL pointer dereference at virtual address 00000084
pgd = dfb44000 [00000084] *pgd=1fb99031, *pte=00000000, *ppte=00000000
Internal error: Oops: 17 [#1] PREEMPT
last sysfs file:
/sys/devices/platform/mvsdio/mmc_host/mmc0/mmc0:f111/uevent
Modules linked in:
CPU: 0 Not tainted (2.6.32-rc5-next-20091102-00001-gb36eae9 #10)
PC is at sdio_uart_open+0x204/0x2cc
[...]
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Add a tty_port object to the sdio uart. For the moment just begin using the
tty field of the port, as this is the critical one to clean up.
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Move the HUCPL handling from the end of close_port_start to the beginning
of close_port_end. What this actually does is change the ordering from
port shutdown
port->dtr_rts
to
port->dtr_rts
port shutdown
Some hardware drops the physical connection on shutdown so we must perform
the port operations before the shutdown.
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
devpts_get_tty() assumes that the inode passed in is associated with a valid
pty. But if the only reference to the pty is via a bind-mount, the inode
passed to devpts_get_tty() while valid, would refer to a pty that no longer
exists.
With a lot of debug effort, Grzegorz Nosek developed a small program (see
below) to reproduce a crash on recent kernels. This crash is a regression
introduced by the commit:
commit 527b3e4773
Author: Sukadev Bhattiprolu <sukadev@us.ibm.com>
Date: Mon Oct 13 10:43:08 2008 +0100
To fix, ensure that the dentry associated with the inode has not yet been
deleted/unhashed by devpts_pty_kill().
See also:
https://lists.linux-foundation.org/pipermail/containers/2009-July/019273.html
tty-bug.c:
#define _GNU_SOURCE
#include <fcntl.h>
#include <sched.h>
#include <stdlib.h>
#include <sys/mount.h>
#include <sys/signal.h>
#include <unistd.h>
#include <stdio.h>
#include <linux/fs.h>
void dummy(int sig)
{
}
static int child(void *unused)
{
int fd;
signal(SIGINT, dummy); signal(SIGHUP, dummy);
pause(); /* cheesy synchronisation to wait for /dev/pts/0 to appear */
mount("/dev/pts/0", "/dev/console", NULL, MS_BIND, NULL);
sleep(2);
fd = open("/dev/console", O_RDWR);
dup(0); dup(0);
write(1, "Hello world!\n", sizeof("Hello world!\n")-1);
return 0;
}
int main(void)
{
pid_t pid;
char *stack;
stack = malloc(16384);
pid = clone(child, stack+16384, CLONE_NEWNS|SIGCHLD, NULL);
open("/dev/ptmx", O_RDWR|O_NOCTTY|O_NONBLOCK);
unlockpt(fd); grantpt(fd);
sleep(2);
kill(pid, SIGHUP);
sleep(1);
return 0; /* exit before child opens /dev/console */
}
Reported-by: Grzegorz Nosek <root@localdomain.pl>
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Tested-by: Serge Hallyn <serue@us.ibm.com>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Do not read IIR in serial8250_start_tx when UART_BUG_TXEN
Reading the IIR clears some oustanding interrupts so it is not safe.
Instead, simply transmit immediately if the buffer is empty without
regard to IIR.
Signed-off-by: Ian Jackson <ian.jackson@eu.citrix.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Jiri Kosina <jkosina@suse.cz>
Cc: Alan Cox <alan@linux.intel.com>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Intel(R) PXA27x Processor Family Specification Update (Nov 2005)
says:
E75. UART: Baud rate may not be programmed correctly on
back-to-back writes.
Problem:
When programming the Divisor Latch registers, Low and High (DLL and
DLH), with back-to-back writes, the second register write may not
take effect. The result is an incorrect baud rate.
Workaround:
After programming the first Divisor Latch register, read and verify
it before programming the second Divisor Latch register.
This was hit when changing the baud rate from 115200 to 9600 while
receiving characters at 9600 Bd.
And fixed indention of some comments nearby.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Wolfram Sang <w.sang@pengutronix.de>
Acked-by: Marc Kleine-Budde <mkl@pengutronix.de>
Cc: Eric Miao <eric.y.miao@gmail.com>
Cc: Alan Cox <alan@linux.intel.com>
Cc: Mike Rapoport <mike@compulab.co.il>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Opticon now takes the right mutex to check the port status but the status
check is done wrongly for the modern serial code, so fix it.
Signed-off-by: Alan Cox <alan@linux.intel.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Oliver Neukum <oliver@neukum.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The tty port has a port mutex used for all the port related locking so we
don't need the one in the USB serial layer any more.
Signed-off-by: Alan Cox <alan@linux.intel.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Oliver Neukum <oliver@neukum.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
As Alan Stern pointed out - now we have tty_port_open the shutdown method
and locking allow us to whack the other bits into the full helper methods
and provide a shutdown op which the tty port code will synchronize with
setup for us.
Signed-off-by: Alan Cox <alan@linux.intel.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Oliver Neukum <oliver@neukum.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
For the moment this just moves the USB logic over and fixes the 'what if
we open and hangup at the same time' race noticed by Oliver Neukum.
Signed-off-by: Alan Cox <alan@linux.intel.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Oliver Neukum <oliver@neukum.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Fairly trivial as the BKL push down into the methods has already been done.
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The ESP driver has been marked broken for years. It's an old ISA device
that clearly nobody cares about any more. Remove it
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Alan Cox
Nicolas Pitre
Sukadev Bhattiprolu
Ian Jackson
Tilman Schmidt
Uwe Kleine-König
André Goddard Rosa