After commit "TTY: move tty buffers to tty_port", the tty buffers are
not freed in some drivers. This is because tty_port_destructor is not
called whenever a tty_port is freed. This was an assumption I counted
with but was unfortunately untrue. So fix the drivers to fulfil this
assumption.

To be sure, the TTY buffers (and later some stuff) are gone along with
the tty_port, we have to call tty_port_destroy at tear-down places.
This is mostly where the structure containing a tty_port is freed.
This patch does exactly that -- put tty_port_destroy at those places.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Pull TTY changes from Greg Kroah-Hartman:
 "As we skipped the merge window for 3.6-rc1 for the tty tree,
  everything is now settled down and working properly, so we are ready
  for 3.7-rc1.  Here's the patchset, it's big, but the large changes are
  removing a firmware file and adding a staging tty driver (it depended
  on the tty core changes, so it's going through this tree instead of
  the staging tree.)

  All of these patches have been in the linux-next tree for a while.

  Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>"

Fix up more-or-less trivial conflicts in
 - drivers/char/pcmcia/synclink_cs.c:
    tty NULL dereference fix vs tty_port_cts_enabled() helper function
 - drivers/staging/{Kconfig,Makefile}:
    add-add conflict (dgrp driver added close to other staging drivers)
 - drivers/staging/ipack/devices/ipoctal.c:
    "split ipoctal_channel from iopctal" vs "TTY: use tty_port_register_device"

* tag 'tty-3.6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (235 commits)
  tty/serial: Add kgdb_nmi driver
  tty/serial/amba-pl011: Quiesce interrupts in poll_get_char
  tty/serial/amba-pl011: Implement poll_init callback
  tty/serial/core: Introduce poll_init callback
  kdb: Turn KGDB_KDB=n stubs into static inlines
  kdb: Implement disable_nmi command
  kernel/debug: Mask KGDB NMI upon entry
  serial: pl011: handle corruption at high clock speeds
  serial: sccnxp: Make 'default' choice in switch last
  serial: sccnxp: Remove mask termios caps for SW flow control
  serial: sccnxp: Report actual baudrate back to core
  serial: samsung: Add poll_get_char & poll_put_char
  Powerpc 8xx CPM_UART setting MAXIDL register proportionaly to baud rate
  Powerpc 8xx CPM_UART maxidl should not depend on fifo size
  Powerpc 8xx CPM_UART too many interrupts
  Powerpc 8xx CPM_UART desynchronisation
  serial: set correct baud_base for EXSYS EX-41092 Dual 16950
  serial: omap: fix the reciever line error case
  8250: blacklist Winbond CIR port
  8250_pnp: do pnp probe before legacy probe
  ...

tty_port_tty_get() can return NULL after port hangup that may happen anytime.
The patch adds checks that tty_port_tty_get() returns nonNULL around places
where tty is actually used.

I have no actual hardware to test the patch, so I have updated rx side
processing from common sense only.

v2: rx handling updated according Alan Cox feedback.

Found by Linux Driver Verification project (linuxtesting.org).

Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

In most of the time, the driver needs to check if the cts flow control
is enabled. But now, the driver checks the ASYNC_CTS_FLOW flag manually,
which is not a grace way. So add a new wraper function to make the code
tidy and clean.

Signed-off-by: Huang Shijie <shijie8@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

We changed these from alloc_tty_driver() to tty_alloc_driver() so the
error handling needs to modified to check for IS_ERR() instead of NULL.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Commit "TTY: synclink_cs, use dynamic tty devices" added a call to
tty_port_register_device with a proper device as the last argument.
But it was not correct and it causes build failures:
synclink_cs.c: In function ‘mgslpc_add_device’:
synclink_cs.c:2735:16: error: request for member ‘dev’ in something not a structure or union

info->p_dev is a pointer, so act as that.

I wonder why my build scripts did not notice. I have to re-check them.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

* use <tab> for indentation
* add KERN_* to printks
* no more assignments in if's like if ((rc = function()))

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

This allows us to provide the tty layer with information about
tty_port for each link. And it also allows us to get rid of the
remove_device loop in synclink_cs_exit because we had to reorder
pcmcia and tty driver registration in init. This was because we need
to have serial_driver initialized when calling
tty_port_register_device from pcmcia ->probe.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

We will need to change the order of tty and pcmcia drivers
initializations (see the reason later in this series). And the fail
path handling is currently performed in a separate function that as
well takes care of proper deinitialization in module_exit. It is hard
to read and will need to be adjusted by our changes anyway. Instead,
get rid of this helper function and do the fail paths handling
directly in the init function. (And move the body of the function to
module_exit.)

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>