359 Commits

Author SHA1 Message Date
Jiri Slaby
e901cc458a TTY: ldisc, wait for ldisc infinitely in hangup
commit 0c73c08ec7 upstream.

For /dev/console case, we do not kill all ldisc users. It's due to
redirected_tty_write test in __tty_hangup. In that case there still
might be a process waiting e.g. in n_tty_read for input.

We wait for such processes to disappear. The problem is that we use a
timeout. After this timeout, we continue closing the ldisc and start
freeing tty resources. It obviously leads to crashes when the other
process is woken.

So to fix this, we wait infinitely before reiniting the ldisc. (The
tiocsetd remains untouched -- times out after 5s.)

This is nicely reproducible with this run from shell:
  exec 0<>/dev/console 1<>/dev/console 2<>/dev/console
and stopping a getty like:
  systemctl stop serial-getty@ttyS0.service

The crash proper may be produced only under load or with constified
timing the same as for 92f6fa09b.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Dave Young <hidave.darkstar@gmail.com>
Cc: Dave Jones <davej@redhat.com>
Cc: Ben Hutchings <ben@decadent.org.uk>
Cc: Dmitriy Matrosov <sgf.dma@gmail.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-11-26 09:08:36 -08:00
Jiri Slaby
bb4006e04c TTY: ldisc, move wait idle to caller
commit 300420722e upstream.

It is the only place where reinit is called from. And we really need
to wait for the old ldisc to go once. Actually this is the place where
the waiting originally was (before removed and re-added later).

This will make the fix in the following patch easier to implement.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Dave Young <hidave.darkstar@gmail.com>
Cc: Dave Jones <davej@redhat.com>
Cc: Ben Hutchings <ben@decadent.org.uk>
Cc: Dmitriy Matrosov <sgf.dma@gmail.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-11-26 09:08:36 -08:00
Jiri Slaby
d21ada2ca3 TTY: ldisc, allow waiting for ldisc arbitrarily long
commit df92d0561d upstream.

To fix a nasty bug in ldisc hup vs. reinit we need to wait infinitely
long for ldisc to be gone. So here we add a parameter to
tty_ldisc_wait_idle to allow that.

This is only a preparation for the real fix which is done in the
following patches.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Dave Young <hidave.darkstar@gmail.com>
Cc: Dave Jones <davej@redhat.com>
Cc: Ben Hutchings <ben@decadent.org.uk>
Cc: Dmitriy Matrosov <sgf.dma@gmail.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-11-26 09:08:36 -08:00
Stephen Boyd
5a25cbde3f tty: hvc_dcc: Fix duplicate character inputs
commit c2a3e84f95 upstream.

Reading from the DCC grabs a character from the buffer and
clears the status bit. Since this is a context-changing
operation, instructions following the character read that rely on
the status bit being accurate need to be synchronized with an
ISB.

In this case, the status bit check needs to execute after the
character read otherwise we run the risk of reading the character
and checking the status bit before the read can clear the status
bit in the first place. When this happens, the user will see the
same character they typed twice, instead of once.

Add an ISB after the read and the write, so that the status check
is synchronized with the read/write operations.

Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-11-26 09:08:35 -08:00
Tomoya MORINAGA
39e005fc9f pch_uart: Support new device LAPIS Semiconductor ML7831 IOH
commit 8249f743f7 upstream.

ML7831 is companion chip for Intel Atom E6xx series.

Signed-off-by: Tomoya MORINAGA <tomoya-linux@dsn.lapis-semi.com>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-11-26 09:08:35 -08:00
Tomoya MORINAGA
091fb7d008 pch_uart: Fix DMA resource leak issue
commit 90f04c2926 upstream.

Changing UART mode PIO->DMA->PIO->DMA like below, pch_uart driver can't get
DMA channel resource.

setserial /dev/ttyPCH0 ^low_latency
setserial /dev/ttyPCH0 low_latency

CAUSE:
Changing mode using setserial command, ".startup" function which gets DMA
channel is called before ".verify_port" function which sets
dma-flag(use_dma/use_dma_flag) as 1.

PIO->DMA
  .startup: Since dma-flag is 0, DMA channel is not requested.
  .verify_port: dma-flag is set as 1.
  .shutdown: N/A

DMA->PIO
  .startup: Since dma-flag is 1, DMA channel is requested.
  .verify_port: dma-flag is set as 0.
  .shutdown: Since dma-flag is 0, DMA channel is not released.

This means DMA channel resource leak occurs.
Next time, this driver can't get DMA channel resource forever.

MODIFICATION:
  Currently, when release DMA channel resource, this driver checks dma-flag.
  However, this specification occurs the above issue.
  This driver must check whether dma_request_channel is executed or not.
  The values are saved in private data variable "chan_tx/chan_tx".
  These variables mean if the value is NULL, DMA channel is not requested,
  if not NULL, DMA channel is requested.

This patch fixes the issue.

Signed-off-by: Tomoya MORINAGA <tomoya.rohm@gmail.com>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-11-26 09:08:35 -08:00
Tomoya MORINAGA
81aaad2ca2 pch_uart: Fix hw-flow control issue
commit a1d7cfe29f upstream.

Using hardware flow control,
currently, register of the control-bit(AFE) is not set.
This patch fixes the issue.

Signed-off-by: Tomoya MORINAGA <tomoya-linux@dsn.lapis-semi.com>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-11-26 09:08:35 -08:00
Thadeu Lima de Souza Cascardo
3512abc224 jsm: remove buggy write queue
commit 9d898966c4 upstream.

jsm uses a write queue that copies from uart_core circular buffer. This
copying however has some bugs, like not wrapping the head counter. Since
this write queue is also a circular buffer, the consumer function is
ready to use the uart_core circular buffer directly.

This buggy copying function was making some bytes be dropped when
transmitting to a raw tty, doing something like this.

[root@hostname ~]$ cat /dev/ttyn1 > cascardo/dump &
[1] 2658
[root@hostname ~]$ cat /proc/tty/drivers > /dev/ttyn0
[root@hostname ~]$ cat /proc/tty/drivers
/dev/tty             /dev/tty        5       0 system:/dev/tty
/dev/console         /dev/console    5       1 system:console
/dev/ptmx            /dev/ptmx       5       2 system
/dev/vc/0            /dev/vc/0       4       0 system:vtmaster
jsm                  /dev/ttyn     250 0-31 serial
serial               /dev/ttyS       4 64-95 serial
hvc                  /dev/hvc      229 0-7 system
pty_slave            /dev/pts      136 0-1048575 pty:slave
pty_master           /dev/ptm      128 0-1048575 pty:master
unknown              /dev/tty        4 1-63 console
[root@hostname ~]$ cat cascardo/dump
/dev/tty             /dev/tty        5       0 system:/dev/tty
/dev/console         /dev/console    5       1 system:console
/dev/ptmx            /dev/ptmx       5       2 system
/dev/vc/0            /dev/vc/0       4       0 system:vtmaste[root@hostname ~]$

This patch drops the driver write queue entirely, using the circular
buffer from uart_core only.

Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@linux.vnet.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-11-11 09:43:38 -08:00
Ning Jiang
a717f83d88 serial-core: power up uart port early before we do set_termios when resuming
commit 94abc56f4d upstream.

The following patch removed uart_change_pm() in uart_resume_port():

commit 5933a161ab
Author: Yin Kangkai <kangkai.yin@linux.intel.com>
    serial-core: reset the console speed on resume

It will break the pxa serial driver when the system resumes from suspend mode
as it will try to set baud rate divider register in set_termios but with
clock off. The register value can not be set correctly on some platform if
the clock is disabled. The pxa driver will check the value and report the
following warning:

------------[ cut here ]------------
WARNING: at drivers/tty/serial/pxa.c:545 serial_pxa_set_termios+0x1dc/0x250()
Modules linked in:
[<c0281f30>] (unwind_backtrace+0x0/0xf0) from [<c029341c>] (warn_slowpath_common+0x4c/0x64)
[<c029341c>] (warn_slowpath_common+0x4c/0x64) from [<c029344c>] (warn_slowpath_null+0x18/0x1c)
[<c029344c>] (warn_slowpath_null+0x18/0x1c) from [<c044b1e4>] (serial_pxa_set_termios+0x1dc/0x250)
[<c044b1e4>] (serial_pxa_set_termios+0x1dc/0x250) from [<c044a840>] (uart_resume_port+0x128/0x2dc)
[<c044a840>] (uart_resume_port+0x128/0x2dc) from [<c044bbe0>] (serial_pxa_resume+0x18/0x24)
[<c044bbe0>] (serial_pxa_resume+0x18/0x24) from [<c0454d34>] (platform_pm_resume+0x40/0x4c)
[<c0454d34>] (platform_pm_resume+0x40/0x4c) from [<c0457ebc>] (pm_op+0x68/0xb4)
[<c0457ebc>] (pm_op+0x68/0xb4) from [<c0458368>] (device_resume+0xb0/0xec)
[<c0458368>] (device_resume+0xb0/0xec) from [<c04584c8>] (dpm_resume+0xe0/0x194)
[<c04584c8>] (dpm_resume+0xe0/0x194) from [<c0458588>] (dpm_resume_end+0xc/0x18)
[<c0458588>] (dpm_resume_end+0xc/0x18) from [<c02c518c>] (suspend_devices_and_enter+0x16c/0x1ac)
[<c02c518c>] (suspend_devices_and_enter+0x16c/0x1ac) from [<c02c5278>] (enter_state+0xac/0xdc)
[<c02c5278>] (enter_state+0xac/0xdc) from [<c02c48ec>] (state_store+0xa0/0xbc)
[<c02c48ec>] (state_store+0xa0/0xbc) from [<c0408f7c>] (kobj_attr_store+0x18/0x1c)
[<c0408f7c>] (kobj_attr_store+0x18/0x1c) from [<c034a6a4>] (sysfs_write_file+0x108/0x140)
[<c034a6a4>] (sysfs_write_file+0x108/0x140) from [<c02fb798>] (vfs_write+0xac/0x134)
[<c02fb798>] (vfs_write+0xac/0x134) from [<c02fb8cc>] (sys_write+0x3c/0x68)
[<c02fb8cc>] (sys_write+0x3c/0x68) from [<c027c700>] (ret_fast_syscall+0x0/0x2c)
---[ end trace 88289eceb4675b04 ]---

This patch fix the problem by adding the power on opertion back for uart
console when console_suspend_enabled is true.

Signed-off-by: Ning Jiang <ning.jiang@marvell.com>
Tested-by: Mayank Rana <mrana@codeaurora.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-11-11 09:42:18 -08:00
Marcus Folkesson
fcdff906db serial: pxa: work around for errata #20
commit e44aabd649 upstream.

Errata E20: UART: Character Timeout interrupt remains set under certain
software conditions.

Implication: The software servicing the UART can be trapped in an infinite loop.

Signed-off-by: Marcus Folkesson <marcus.folkesson@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-11-11 09:42:18 -08:00
Jiri Slaby
368f255e47 TTY: pty, release tty in all ptmx_open fail paths
commit 1177c0efc0 upstream.

Mistakenly, commit 64ba3dc314 (tty: never hold BTM while getting
tty_mutex) switched one fail path in ptmx_open to not free the newly
allocated tty.

Fix that by jumping to the appropriate place. And rename the labels so
that it's clear what is going on there.

Introduced-in: v2.6.36-rc2
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-11-11 09:42:12 -08:00
Jiri Slaby
5112c311dc TTY: make tty_add_file non-failing
commit fa90e1c935 upstream.

If tty_add_file fails at the point it is now, we have to revert all
the changes we did to the tty. It means either decrease all refcounts
if this was a tty reopen or delete the tty if it was newly allocated.

There was a try to fix this in v3.0-rc2 using tty_release in 0259894c7
(TTY: fix fail path in tty_open). But instead it introduced a NULL
dereference. It's because tty_release dereferences
filp->private_data, but that one is set even in our tty_add_file. And
when tty_add_file fails, it's still NULL/garbage. Hence tty_release
cannot be called there.

To circumvent the original leak (and the current NULL deref) we split
tty_add_file into two functions, making the latter non-failing. In
that case we may do the former early in open, where handling failures
is easy. The latter stays as it is now. So there is no change in
functionality.

The original bug (leak) was introduced by f573bd176 (tty: Remove
__GFP_NOFAIL from tty_add_file()). Thanks Dan for reporting this.

Later, we may split tty_release into more functions and call only some
of them in this fail path instead. (If at all possible.)

Introduced-in: v2.6.37-rc2
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Pekka Enberg <penberg@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-11-11 09:42:12 -08:00
Jiri Slaby
bebd46c74c TTY: drop driver reference in tty_open fail path
commit c290f8358a upstream.

When tty_driver_lookup_tty fails in tty_open, we forget to drop a
reference to the tty driver. This was added by commit 4a2b5fddd5 (Move
tty lookup/reopen to caller).

Fix that by adding tty_driver_kref_put to the fail path.

I will refactor the code later. This is for the ease of backporting to
stable.

Introduced-in: v2.6.28-rc2
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Acked-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-11-11 09:42:11 -08:00
Linus Torvalds
a24d025a08 Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/upstream-linus
* 'upstream' of git://git.linux-mips.org/pub/scm/upstream-linus: (29 commits)
  MIPS: Call oops_enter, oops_exit in die
  staging/octeon: Software should check the checksum of no tcp/udp packets
  MIPS: Octeon: Enable C0_UserLocal probing.
  MIPS: No branches in delay slots for huge pages in handle_tlbl
  MIPS: Don't clobber CP0_STATUS value for CONFIG_MIPS_MT_SMTC
  MIPS: Octeon: Select CONFIG_HOLES_IN_ZONE
  MIPS: PM: Use struct syscore_ops instead of sysdevs for PM (v2)
  MIPS: Compat: Use 32-bit wrapper for compat_sys_futex.
  MIPS: Do not use EXTRA_CFLAGS
  MIPS: Alchemy: DB1200: Disable cascade IRQ in handler
  SERIAL: Lantiq: Set timeout in uart_port
  MIPS: Lantiq: Fix setting the PCI bus speed on AR9
  MIPS: Lantiq: Fix external interrupt sources
  MIPS: tlbex: Fix build error in R3000 code.
  MIPS: Alchemy: Include Au1100 in PM code.
  MIPS: Alchemy: Fix typo in MAC0 registration
  MIPS: MSP71xx: Fix build error.
  MIPS: Handle __put_user() sleeping.
  MIPS: Allow forced irq threading
  MIPS: i8259: Mark cascade interrupt non-threaded
  ...
2011-10-10 14:39:03 +12:00
John Crispin
b7867f1bfc SERIAL: Lantiq: Set timeout in uart_port
Without this patch apps using readline hang.

Signed-off-by: Thomas Langer <thomas.langer@lantiq.com>
Signed-off-by: John Crispin <blogic@openwrt.org>
Cc: linux-mips@linux-mips.org
Cc: linux-serial@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/2687/
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2011-09-21 17:53:25 +02:00
WANG Cong
83ede96e98 cris: fix a build error in drivers/tty/serial/crisv10.c
Fix these errors:

    drivers/tty/serial/crisv10.c:4453: error: 'if_ser0' undeclared (first use in this function): 2 errors in 2 logs
    drivers/tty/serial/crisv10.c:4453: error: (Each undeclared identifier is reported only once: 2 errors in 2 logs
    drivers/tty/serial/crisv10.c:4453: error: for each function it appears in.): 2 errors in 2 logs

"if_ser0" is a typo, it should be "if_serial_0".

Signed-off-by: WANG Cong <xiyou.wangcong@gmail.com>
Cc: Mikael Starvik <starvik@axis.com>
Cc: Jesper Nilsson <jesper.nilsson@axis.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-09-14 18:09:38 -07:00
Linus Torvalds
c42a2634d8 Merge branch 'sh-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/lethal/sh-3.x
* 'sh-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/lethal/sh-3.x:
  sh: fix the compile error in setup-sh7757.c
  serial: sh-sci: report CTS as active for get_mctrl
  sh: Add unaligned memory access for PC relative intructions
  sh: Fix unaligned memory access for branches without delay slots
  sh: Fix up fallout from cpuidle changes.
  serial: sh-sci: console Runtime PM support
  sh: Fix conflicting definitions of ptrace_triggered
  serial: sh-sci: fix DMA build by including dma-mapping.h
  serial: sh-sci: Fix up default regtype probing.
  sh: intc: enable both edges GPIO interrupts on sh7372
  shwdt: fix usage of mod_timer
  clocksource: sh_cmt: wait for CMCNT on init V2
2011-08-29 13:34:48 -07:00
Yoshii Takashi
4480a688b2 serial: sh-sci: report CTS as active for get_mctrl
sh-sci.c sets hardware up and then let the HW do all flow controls.
There is no software code, nor needs to get/set real CTS signal.

But, when turning CRTSCTS on through termios, uart_set_termios() in
serial_core.c checks CTS, and stops TX if it is inactive at the moment.

Because sci_get_mctrl() returns a fixed value DTR|RTS|DSR but CTS,
the sequence
  open -> set CRTSCTS -> write
hit the case and stop working, no more outputs.

This patch makes sci_get_mctrl() report CTS in addition.

Signed-off-by: Takashi YOSHII <takashi.yoshii.zj@renesas.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2011-08-29 15:47:33 +09:00
Linus Torvalds
c11a7e26f8 Merge branch 'pm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
* 'pm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  ARM: mach-shmobile: sh7372 LCDC1 suspend fix V2 (incremental)
  OMAP: omap_device: only override _noirq methods, not normal suspend/resume
  PM / Runtime: Correct documentation of pm_runtime_irq_safe()
  ARM: mach-shmobile: sh7372 LCDC1 suspend fix
  sh-sci / PM: Use power.irq_safe
  PM: Use spinlock instead of mutex in clock management functions
2011-08-28 10:05:39 -07:00
Rafael J. Wysocki
5a50a01bf0 sh-sci / PM: Use power.irq_safe
Since sci_port_enable() and sci_port_disable() may be run with
interrupts off and they execute pm_runtime_get_sync() and
pm_runtime_put_sync(), respectively, the SCI device's
power.irq_safe flag has to be set to indicate that it is safe
to execute runtime PM callbacks for this device with interrupts off.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Magnus Damm <damm@opensource.se>
2011-08-24 21:41:08 +02:00
Nick Pelly
b280a97d1c omap-serial: Allow IXON and IXOFF to be disabled.
Fixes logic bug that software flow control cannot be disabled, because
serial_omap_configure_xonxoff() is not called if both IXON and IXOFF bits
are cleared.

Signed-off-by: Nick Pelly <npelly@google.com>
Acked-by: Govindraj.R <govindraj.raja@ti.com>
Tested-by: Govindraj.R <govindraj.raja@ti.com>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-08-23 10:58:38 -07:00
Jiri Slaby
0055197e98 TTY: serial, document ignoring of uart->ops->startup error
When a user has SYS_ADMIN capabilities and uart->ops->startup returns
an error in uart_startup, we silently drop the error. We then return 0
and behave as if it didn't fail. (Not quite, since we set TTY_IO_ERROR
bit and leave ASYNC_INITIALIZED bit cleared.)

This all is to allow setserial to work with improperly configured or
unconfigured ports. User can thus set port properties and reconfigure
properly.

This patch only documents this behavior.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Russel King <linux@arm.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-08-23 10:10:38 -07:00
Jiri Slaby
24d406a6bf TTY: pty, fix pty counting
tty_operations->remove is normally called like:
queue_release_one_tty
 ->tty_shutdown
   ->tty_driver_remove_tty
     ->tty_operations->remove

However tty_shutdown() is called from queue_release_one_tty() only if
tty_operations->shutdown is NULL. But for pty, it is not.
pty_unix98_shutdown() is used there as ->shutdown.

So tty_operations->remove of pty (i.e. pty_unix98_remove()) is never
called. This results in invalid pty_count. I.e. what can be seen in
/proc/sys/kernel/pty/nr.

I see this was already reported at:
  https://lkml.org/lkml/2009/11/5/370
But it was not fixed since then.

This patch is kind of a hackish way. The problem lies in ->install. We
allocate there another tty (so-called tty->link). So ->install is
called once, but ->remove twice, for both tty and tty->link. The fix
here is to count both tty and tty->link and divide the count by 2 for
user.

And to have ->remove called, let's make tty_driver_remove_tty() global
and call that from pty_unix98_shutdown() (tty_operations->shutdown).

While at it, let's document that when ->shutdown is defined,
tty_shutdown() is not called.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Alan Cox <alan@linux.intel.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-08-23 10:10:38 -07:00
Al Cooper
dbb3b1ca56 8250: Fix race condition in serial8250_backup_timeout().
This is to fix an issue where output will suddenly become very slow.
The problem occurs on 8250 UARTS with the hardware bug UART_BUG_THRE.

BACKGROUND
For normal UARTs (without UART_BUG_THRE): When the serial core layer
gets new transmit data and the transmitter is idle, it buffers the
data and calls the 8250s' serial8250_start_tx() routine which will
simply enable the TX interrupt in the IER register and return. This
should immediately fire a THRE interrupt and begin transmitting the
data.
For buggy UARTs (with UART_BUG_THRE): merely enabling the TX interrupt
in IER does not necessarily generate a new THRE interrupt.
Therefore, a background timer periodically checks to see if there is
pending data, and starts transmission if that is the case.

The bug happens on SMP systems when the system has nothing to transmit,
the transmit interrupt is disabled and the following sequence occurs:
- CPU0: The background timer routine serial8250_backup_timeout()
  starts and saves the state of the interrupt enable register (IER)
  and then disables all interrupts in IER. NOTE: The transmit interrupt
  (TI) bit is saved as disabled.
- CPU1: The serial core gets data to transmit, grabs the port lock and
  calls serial8250_start_tx() which enables the TI in IER.
- CPU0: serial8250_backup_timeout() waits for the port lock.
- CPU1: finishes (with TI enabled) and releases the port lock.
- CPU0: serial8250_backup_timeout() calls the interrupt routine which
  will transmit the next fifo's worth of data and then restores the
  IER from the previously saved value (TI disabled).
At this point, as long as the serial core has more transmit data
buffered, it will not call serial8250_start_tx() again and the
background timer routine will slowly transmit the data.

The fix is to have serial8250_start_tx() get the port lock before
it saves the IER state and release it after restoring IER. This will
prevent serial8250_start_tx() from running in parallel.

Signed-off-by: Al Cooper <alcooperx@gmail.com>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-08-23 10:10:37 -07:00
Tomoya MORINAGA
dacacc3e79 serial/8250_pci: delete duplicate data definition
Data definiton "VendorID=10DB, device_id=800D" is already defined.
This patch deletes the duplicate definition.

Signed-off-by: Tomoya MORINAGA <tomoya-linux@dsn.okisemi.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-08-23 10:06:28 -07:00
Eric Smith
44178176ec 8250_pci: add support for Rosewill RC-305 4x serial port card
This patch adds support for the Rosewill RC-305 four-port PCI serial
card, and probably any other four-port serial cards based on the
Moschip MCS9865 chip, assuming that the EEPROM on the card was
programmed in accordance with Table 6 of the MCS9865 EEPROM
Application Note version 0.3 dated 16-May-2008, available from the
Moschip web site (registration required).

This patch is based on an earlier patch [1] for the SYBA 6x serial
port card by Ira W. Snyder.

[1]: http://www.gossamer-threads.com/lists/linux/kernel/1162435

Signed-off-by: Eric Smith <eric@brouhaha.com>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-08-23 10:05:10 -07:00
Axel Lin
8c4074cd22 tty: Add "spi:" prefix for spi modalias
Since commit e0626e38 (spi: prefix modalias with "spi:"),
the spi modalias is prefixed with "spi:".

This patch adds "spi:" prefix and removes "-spi" suffix in the modalias.

Signed-off-by: Axel Lin <axel.lin@gmail.com>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-08-23 10:02:01 -07:00
Voss, Nikolaus
0d0a3cc183 atmel_serial: fix atmel_default_console_device
reflect new static uart platform ids introduced by patch
http://article.gmane.org/gmane.linux.kernel/1126105

Signed-off-by: Nikolaus Voss <n.voss@weinmann.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-08-22 14:18:44 -07:00
Bjorn Helgaas
ab8ba3a2d2 serial: 8250_pnp: add Intermec CV60 touchscreen device
It would have been nice if Intermec had supplied a PNP0501 _CID for the
COM3 device, but they didn't, so we have to recognize it explicitly.

Reference: https://bugzilla.kernel.org/show_bug.cgi?id=40612
CC: Jeff Chua <jeff.chua.linux@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: stable <stable@kernel.org>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-08-22 14:18:44 -07:00
Kumar Gala
181d5762bd drivers/serial/ucc_uart.c: Fix compiler warning
drivers/tty/serial/ucc_uart.c: In function 'qe2cpu_addr':
drivers/tty/serial/ucc_uart.c:238:2: warning: format '%x' expects type 'unsigned int', but argument 3 has type 'dma_addr_t'

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Acked-by: Timur Tabi <timur@freescale.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-08-22 14:18:43 -07:00
Tomoya MORINAGA
6c4b47d243 pch_uart: Set PCIe bus number using probe parameter
Currently, PCIe bus number is set as fixed value "2".
However, PCIe bus number is not always "2".
This patch sets bus number using probe() parameter.

Signed-off-by: Tomoya MORINAGA <tomoya-linux@dsn.okisemi.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-08-22 14:18:42 -07:00
Kukjin Kim
b882fc1b03 serial: samsung: Fix build error
drivers/tty/serial/samsung.c: In function 's3c24xx_serial_init':
drivers/tty/serial/samsung.c:1237: error: lvalue required as unary '&' operand

Cc: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-08-08 13:54:50 -07:00
Paul Mundt
77c7ee51a0 Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux into sh-latest
Conflicts:
	drivers/tty/serial/sh-sci.c

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2011-08-08 13:45:28 +09:00
Rafael J. Wysocki
fc97114b8d sh: Fix boot crash related to SCI
Commit d006199e72a9 ("serial: sh-sci: Regtype probing doesn't need to be
fatal.") made sci_init_single() return when sci_probe_regmap() succeeds,
although it should return when sci_probe_regmap() fails.  This causes
systems using the serial sh-sci driver to crash during boot.

Fix the problem by using the right return condition.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-08-07 15:51:45 -07:00
Grant Likely
9e191b22c9 dt: remove of_alias_get_id() reference
of_alias_get_id() is broken and being reverted.  Remove the reference
to it and replace with a single incrementing id number.

There is no risk of regression here on the imx driver since the imx
change to use of_alias_get_id() is commit 22698aa2, "serial/imx: add
device tree probe support" which is new for v3.1, and it won't get
used unless CONFIG_OF is enabled and the board is booted using a
device tree.  A single incrementing integer is sufficient for now.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Shawn Guo <shawn.guo@linaro.org>
2011-08-04 11:16:04 +01:00
Magnus Damm
1ba7622094 serial: sh-sci: console Runtime PM support
Add Runtime PM context save/restore support to
the SCIF driver. Tested on the AP4EVB console.

Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2011-08-03 15:07:44 +09:00
Magnus Damm
5beabc7fcd serial: sh-sci: fix DMA build by including dma-mapping.h
Include dma-mapping.h to fix build of the sh-sci driver on
SH-Mobile ARM (sh73a0) when CONFIG_SERIAL_SH_SCI_DMA=y:

drivers/tty/serial/sh-sci.c: In function 'sci_rx_dma_release':
drivers/tty/serial/sh-sci.c:1182:3: error: implicit declaration of function 'dma_free_coherent'
drivers/tty/serial/sh-sci.c: In function 'work_fn_tx':
drivers/tty/serial/sh-sci.c:1333:2: error: implicit declaration of function 'dma_sync_sg_for_device'
drivers/tty/serial/sh-sci.c: In function 'sci_request_dma':
drivers/tty/serial/sh-sci.c:1498:3: error: implicit declaration of function 'dma_map_sg'
drivers/tty/serial/sh-sci.c:1527:3: error: implicit declaration of function 'dma_alloc_coherent'
drivers/tty/serial/sh-sci.c:1527:10: warning: assignment makes pointer from integer without a cast
make[3]: *** [drivers/tty/serial/sh-sci.o] Error 1
make[2]: *** [drivers/tty/serial] Error 2
make[1]: *** [drivers/tty] Error 2
make: *** [drivers] Error 2

Signed-off-by: Magnus Damm <damm@opensource.se>
Tested-by: Simon Horman <horms@verge.net.au>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2011-08-03 12:37:12 +09:00
Paul Mundt
ad75b88ac3 serial: sh-sci: Fix up default regtype probing.
Presently the default regtype probing inadvertently bails out due to an
inverted error check. This fixes it up, and gets platforms without
explicit regtype specifications working again.

Reported-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2011-08-03 12:33:20 +09:00
Linus Torvalds
e10b87d2b5 Merge branch 'sh-latest' of git://git.kernel.org/pub/scm/linux/kernel/git/lethal/sh-3.x
* 'sh-latest' of git://git.kernel.org/pub/scm/linux/kernel/git/lethal/sh-3.x: (39 commits)
  SH: static should be at beginning of declaration
  sh: move CLKDEV_xxx_ID macro to sh_clk.h
  sh: clock-shx3: add CLKDEV_ICK_ID for cleanup
  sh: clock-sh7786: add CLKDEV_ICK_ID for cleanup
  sh: clock-sh7785: add CLKDEV_ICK_ID for cleanup
  sh: clock-sh7757: add CLKDEV_ICK_ID for cleanup
  sh: clock-sh7366: add CLKDEV_ICK_ID for cleanup
  sh: clock-sh7343: add CLKDEV_ICK_ID for cleanup
  sh: clock-sh7722: add CLKDEV_ICK_ID for cleanup
  sh: clock-sh7724: add CLKDEV_ICK_ID for cleanup
  sh: clock-sh7366: modify I2C clock settings
  sh: clock-sh7343: modify I2C clock settings
  sh: clock-sh7723: modify I2C clock settings
  sh: clock-sh7722: modify I2C clock settings
  sh: clock-sh7724: modify I2C clock settings
  serial: sh-sci: Fix up pretty name printing for port IRQs.
  serial: sh-sci: Kill off per-port enable/disable callbacks.
  serial: sh-sci: Add missing module description/author bits.
  serial: sh-sci: Regtype probing doesn't need to be fatal.
  sh: Tidy up pre-clkdev clk_get() error handling.
  ...
2011-08-01 06:10:16 -10:00
Shawn Guo
22698aa252 serial/imx: add device tree probe support
It adds device tree probe support for imx tty/serial driver.

Signed-off-by: Jeremy Kerr <jeremy.kerr@canonical.com>
Signed-off-by: Jason Liu <jason.hui@linaro.org>
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Alan Cox <alan@linux.intel.com>
Cc: Cc: Greg Kroah-Hartman <gregkh@suse.de>
Cc: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
2011-07-27 09:30:43 +08:00
Shawn Guo
fe6b540ac0 serial/imx: get rid of the uses of cpu_is_mx1()
The patch removes all the uses of cpu_is_mx1().  Instead, it uses
the .id_table of platform_driver to distinguish the uart device type,
IMX1_UART and IMX21_UART.  The IMX21_UART type runs on all i.mx
except i.mx1.

A couple of !cpu_is_mx1 logic gets turned into is_imx21_uart,
as the codes wrapped there are really IMX21 type uart specific.

It also removes macro MX1_UCR3_REF25 and MX1_UCR3_REF30 which are
not used anywhere.

Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Alan Cox <alan@linux.intel.com>
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
2011-07-27 09:30:38 +08:00
Arun Sharma
60063497a9 atomic: use <linux/atomic.h>
This allows us to move duplicated code in <asm/atomic.h>
(atomic_inc_not_zero() for now) to <linux/atomic.h>

Signed-off-by: Arun Sharma <asharma@fb.com>
Reviewed-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: David Miller <davem@davemloft.net>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-07-26 16:49:47 -07:00
Linus Torvalds
d5ef642355 Merge branch 'tty-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty-2.6
* 'tty-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty-2.6: (26 commits)
  amba pl011: workaround for uart registers lockup
  n_gsm: fix the wrong FCS handling
  pch_uart: add missing comment about OKI ML7223
  pch_uart: Add MSI support
  tty: fix "IRQ45: nobody cared"
  PTI feature to allow user to name and mark masterchannel request.
  0 for o PTI Makefile bug.
  tty: serial: samsung.c remove legacy PM code.
  SERIAL: SC26xx: Fix link error.
  serial: mrst_max3110: initialize waitqueue earlier
  mrst_max3110: Change max missing message priority.
  tty: s5pv210: Add delay loop on fifo reset function for UART
  tty/serial: Fix XSCALE serial ports, e.g. ce4100
  serial: bfin_5xx: fix off-by-one with resource size
  drivers/tty: use printk_ratelimited() instead of printk_ratelimit()
  tty: n_gsm: Added refcount usage to gsm_mux and gsm_dlci structs
  tty: n_gsm: Add raw-ip support
  tty: n_gsm: expose gsmtty device nodes at ldisc open time
  pch_phub: Fix register miss-setting issue
  serial: 8250, increase PASS_LIMIT
  ...
2011-07-25 23:09:27 -07:00
Linus Torvalds
184475029a Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc
* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc: (99 commits)
  drivers/virt: add missing linux/interrupt.h to fsl_hypervisor.c
  powerpc/85xx: fix mpic configuration in CAMP mode
  powerpc: Copy back TIF flags on return from softirq stack
  powerpc/64: Make server perfmon only built on ppc64 server devices
  powerpc/pseries: Fix hvc_vio.c build due to recent changes
  powerpc: Exporting boot_cpuid_phys
  powerpc: Add CFAR to oops output
  hvc_console: Add kdb support
  powerpc/pseries: Fix hvterm_raw_get_chars to accept < 16 chars, fixing xmon
  powerpc/irq: Quieten irq mapping printks
  powerpc: Enable lockup and hung task detectors in pseries and ppc64 defeconfigs
  powerpc: Add mpt2sas driver to pseries and ppc64 defconfig
  powerpc: Disable IRQs off tracer in ppc64 defconfig
  powerpc: Sync pseries and ppc64 defconfigs
  powerpc/pseries/hvconsole: Fix dropped console output
  hvc_console: Improve tty/console put_chars handling
  powerpc/kdump: Fix timeout in crash_kexec_wait_realmode
  powerpc/mm: Fix output of total_ram.
  powerpc/cpufreq: Add cpufreq driver for Momentum Maple boards
  powerpc: Correct annotations of pmu registration functions
  ...

Fix up trivial Kconfig/Makefile conflicts in arch/powerpc, drivers, and
drivers/cpufreq
2011-07-25 22:59:39 -07:00
Linus Torvalds
d3ec4844d4 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (43 commits)
  fs: Merge split strings
  treewide: fix potentially dangerous trailing ';' in #defined values/expressions
  uwb: Fix misspelling of neighbourhood in comment
  net, netfilter: Remove redundant goto in ebt_ulog_packet
  trivial: don't touch files that are removed in the staging tree
  lib/vsprintf: replace link to Draft by final RFC number
  doc: Kconfig: `to be' -> `be'
  doc: Kconfig: Typo: square -> squared
  doc: Konfig: Documentation/power/{pm => apm-acpi}.txt
  drivers/net: static should be at beginning of declaration
  drivers/media: static should be at beginning of declaration
  drivers/i2c: static should be at beginning of declaration
  XTENSA: static should be at beginning of declaration
  SH: static should be at beginning of declaration
  MIPS: static should be at beginning of declaration
  ARM: static should be at beginning of declaration
  rcu: treewide: Do not use rcu_read_lock_held when calling rcu_dereference_check
  Update my e-mail address
  PCIe ASPM: forcedly -> forcibly
  gma500: push through device driver tree
  ...

Fix up trivial conflicts:
 - arch/arm/mach-ep93xx/dma-m2p.c (deleted)
 - drivers/gpio/gpio-ep93xx.c (renamed and context nearby)
 - drivers/net/r8169.c (just context changes)
2011-07-25 13:56:39 -07:00
Linus Torvalds
4b478cedcd Merge branch 'next/deletion' of git+ssh://master.kernel.org/pub/scm/linux/kernel/git/arm/linux-arm-soc
* 'next/deletion' of git+ssh://master.kernel.org/pub/scm/linux/kernel/git/arm/linux-arm-soc:
  ARM: mach-loki: delete
  ARM: mach-s3c2400: delete
  ARM: mach-s3c24a0: delete
2011-07-25 12:43:28 -07:00
Linus Torvalds
ae4c42e4e4 Merge branch 'next/cleanup' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/linux-arm-soc
* 'next/cleanup' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/linux-arm-soc: (133 commits)
  ARM: EXYNOS4: Change devname for FIMD clkdev
  ARM: S3C64XX: Cleanup mach/regs-fb.h from mach-s3c64xx
  ARM: S5PV210: Cleanup mach/regs-fb.h from mach-s5pv210
  ARM: S5PC100: Cleanup mach/regs-fb.h from mach-s5pc100
  ARM: S3C24XX: Use generic s3c_set_platdata for devices
  ARM: S3C64XX: Use generic s3c_set_platdata for OneNAND
  ARM: SAMSUNG: Use generic s3c_set_platdata for NAND
  ARM: SAMSUNG: Use generic s3c_set_platdata for USB OHCI
  ARM: SAMSUNG: Use generic s3c_set_platdata for HWMON
  ARM: SAMSUNG: Use generic s3c_set_platdata for FB
  ARM: SAMSUNG: Use generic s3c_set_platdata for TS
  ARM: S3C64XX: Add PWM backlight support on SMDK6410
  ARM: S5P64X0: Add PWM backlight support on SMDK6450
  ARM: S5P64X0: Add PWM backlight support on SMDK6440
  ARM: S5PC100: Add PWM backlight support on SMDKC100
  ARM: S5PV210: Add PWM backlight support on SMDKV210
  ARM: EXYNOS4: Add PWM backlight support on SMDKC210
  ARM: EXYNOS4: Add PWM backlight support on SMDKV310
  ARM: SAMSUNG: Create a common infrastructure for PWM backlight support
  clocksource: convert 32-bit down counting clocksource on S5PV210/S5P64X0
  ...

Fix up trivial conflict in arch/arm/mach-imx/mach-scb9328.c
2011-07-25 12:38:42 -07:00
Linus Torvalds
8181780c16 Merge branch 'devicetree/next' of git://git.secretlab.ca/git/linux-2.6
* 'devicetree/next' of git://git.secretlab.ca/git/linux-2.6:
  dt: include linux/errno.h in linux/of_address.h
  of/address: Add of_find_matching_node_by_address helper
  dt: remove extra xsysace platform_driver registration
  tty/serial: Add devicetree support for nVidia Tegra serial ports
  dt: add empty of_property_read_u32[_array] for non-dt
  dt: bindings: move SEC node under new crypto/
  dt: add helper function to read u32 arrays
  tty/serial: change of_serial to use new of_property_read_u32() api
  dt: add 'const' for of_property_read_string parameter **out_string
  dt: add helper functions to read u32 and string property values
  tty: of_serial: support for 32 bit accesses
  dt: document the of_serial bindings
  dt/platform: allow device name to be overridden
  drivers/amba: create devices from device tree
  dt: add of_platform_populate() for creating device from the device tree
  dt: Add default match table for bus ids
2011-07-22 14:53:38 -07:00
Kukjin Kim
cf2e9c7b48 Merge branch 'next-samsung-clkdev-fix' into next-samsung-cleanup 2011-07-21 02:09:46 +09:00
Thomas Abraham
5822a5df5e serial: Remove redundant console_initcall from s3c and s5p console drivers
Uart port is registered as a console during the driver's probe.
So explict registration of console with console_initcall is
removed.

Signed-off-by: Thomas Abraham <thomas.ab@samsung.com>
[kgene.kim@samsung.com: removed changes of s3c2400 and s3c24a0]
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
2011-07-20 19:10:43 +09:00