Commit graph

516 commits

Author SHA1 Message Date
Arnd Bergmann
7df5659eef serial/8250: Move UPIO_TSI to powerpc
This iotype is only used by the legacy_serial code in powerpc, so the
code should live there, rather than be compiled in for every 8250
driver.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: linuxppc-dev@lists.ozlabs.org
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Cc: linux-serial@vger.kernel.org
Acked-by: David Daney <david.daney@cavium.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-09-20 09:19:39 +10:00
Guennadi Liakhovetski
937bb6e4c6 serial: sh-sci: don't filter on DMA device, use only channel ID
On some sh-mobile systems there are more than one DMA controllers, that
can be used for serial ports. Specifying a DMA device in sh-sci platform
data unnecessarily restricts the driver to only use one DMA controller.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
[Fixed the trivial conflict in include/linux/serial_sci.h]
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2011-09-19 08:39:17 +05:30
Jiri Kosina
e060c38434 Merge branch 'master' into for-next
Fast-forward merge with Linus to be able to merge patches
based on more recent version of the tree.
2011-09-15 15:08:18 +02:00
Vitaliy Ivanov
fb914ebff5 treewide: typo 'interrrupt' word corrections.
Signed-off-by: Justin P. Mattock <justinmattock@gmail.com>
Signed-off-by: Vitaliy Ivanov <vitalivanov@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2011-09-15 14:13:02 +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
David Brown
cfdad2aba7 msm_serial: Add devicetree support
Add devicetree support to the msm_serial driver.  Clocks are still
queried by direct name from the driver until device tree clock support
is implemented.

Change-Id: Ia6b2ddfcf1e5dc3bd25dd502662f971202e6d56f
Signed-off-by: David Brown <davidb@codeaurora.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
2011-08-29 12:47:36 -07:00
David Brown
886a451bd2 msm_serial: Use relative resources for iomem
Device tree iomem resources are only accessible by index, and not by
name.  The msm_serial devices always have either 1 or 2 iomem
resources, that are always in the same order.  Convert the
platform_get_resource_byname into just platform_get_resource to
facilitate device tree conversion.

Change-Id: I4fd0f1037e07f2725a2a25c7b07dea2ca9397db7
Signed-off-by: David Brown <davidb@codeaurora.org>
2011-08-29 12:47:35 -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
Jamie Iles
7d4008ebb1 tty: add a DesignWare 8250 driver
The Synopsys DesignWare 8250 is an 8250 that has an extra interrupt that
gets raised when writing to the LCR when busy.  To handle this we need
special serial_out, serial_in and handle_irq methods.  Add a new
platform driver that uses these accessors.

Cc: Alan Cox <alan@linux.intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Jamie Iles <jamie@jamieiles.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-08-26 11:38:46 -07:00
Jamie Iles
c7a1bdc5c9 tty: 8250: export serial8250_handle_irq
Allow modules to use the normal 8250 irq handler inside their own.

Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Jamie Iles <jamie@jamieiles.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-08-26 11:38:45 -07:00
Alan Cox
da4e40e271 max3110: Fix up port->tty backreferencing
We want to keep refcounts properly on this against hangup.

Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-08-26 11:01:15 -07:00
Alexander Shishkin
51808f051e max3110: add sysrq support
This patch moves several occurences of similar code inside receive_chars(),
which now also takes care of checking for break and calling sysrq handling
code.

Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-08-26 11:01:15 -07:00
Dirk Brandewie
7b18bd52b2 max3110: wake up fixes
The main thread is waiting on on a wait_queue but wake_up_process() is
used to wake the thread. This reads weirdly. Change wake_up_process() to
wake_up().

Tested on the Moorestown tablet build

Signed-off-by: Dirk Brandewie <dirk.brandewie@gmail.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-08-26 11:01:14 -07:00
Kristen Carlson Accardi
88e5173ff1 hsu: add runtime pm support
Doesn't appear to be much to do here, however having the suspend/resume
functions will allow the d3/d0 transitions to be sent by the pci core.

Signed-off-by: Kristen Carlson Accardi <kristen@linux.intel.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-08-26 11:01:13 -07:00
Jiri Slaby
0b058353ab TTY: use tty_wait_until_sent_from_close in other drivers
Let's use the newly added helper to avoid stalls in drivers which are
not yet ported to tty_port helpers.

Those which are broken (call tty_wait_until_sent with irqs disabled)
are left untouched. They are in a deeper trouble than we are trying to
solve here. This includes amiserial, 68328serial, 68360serial and
crisv10.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-08-25 09:00:42 -07:00
Jiri Slaby
bafb0bd24d TTY: serial, move locking in uart_close
So now, when we handle CLOSING flag, there is no point to hold
port->mutex over the start of uart_close.

Yes, there are still several things to reason about:
* port->count etc is and always was protected by a spinlock
* ->stop_rx is protected by a spinlock. Otherwise it would
  race with interrupts.
* uart_wait_until_sent -- that one is already called without
  port->mutex from set_termios and tty_set_ldisc. Should anything
  be protected there, it would be tx_empty. And by a spinlock.
  8250 does this internally...

This step is needed to fix system stalls. To not create an AB-BA lock
dependency (see next patches).

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-08-25 09:00:39 -07:00
Jiri Slaby
426929f8d3 TTY: serial, use ASYNCB_CLOSING in uart_close
We need to move port->mutex locking after wait_until_sent in
uart_close (for rationale see next patches). But if we did it now, we
would introduce a race between close and open. This is exactly why
port->mutex is locked at the top of uart_close.

To avoid the race, we add ASYNCB_CLOSING to uart_close. Like every
other sane TTY driver. Thanks to tty_port_block_til_ready used in
uart_open we will have this for free. Then we can move the port->mutex
lock.

Also note that this will make the conversion to tty_port helpers
easier. They are currently handling ASYNC_CLOSING flag correctly.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-08-25 09:00:39 -07:00
Thadeu Lima de Souza Cascardo
dfc97fcebd jsm: print byte we are dequeing
Instead of printing the head of the buffer, we should print the tail,
which is the byte we are sending to the device.

Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@linux.vnet.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-08-24 15:29:44 -07:00
Thadeu Lima de Souza Cascardo
9d898966c4 jsm: remove buggy write queue
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>
2011-08-24 15:29:44 -07:00
Thadeu Lima de Souza Cascardo
d64bbeb57f jsm: remove remaining flip buffer code
The flip buffer is not used anymore. Remove its allocation and
declaration in the board structure.

Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@linux.vnet.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-08-24 15:29:43 -07:00
Kukjin Kim
a16913a9b3 tty: Add support serial for EXYNOS4212 SoC
According to add support EXYNOS4212 SoC, we need to enable
SERIAL_S5PV210 on EXYNOS4212.

Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
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>
2011-08-24 15:28:00 -07:00
Bernhard Roth
83cac9f3b4 atmel_serial: RS485: receiving enabled when sending data
By default the atmel_serial driver in RS485 mode disables receiving data until
all data in the send buffer has been sent. This flag allows to receive data
even whilst sending data.

Signed-off-by: Bernhard Roth <br@pwrnet.de>
Signed-off-by: Claudio Scordino <claudio@evidence.eu.com>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-08-24 15:27:59 -07:00
Hui Wang
019dc9ea8d serial/imx: support to handle break character
The imx UART hardware controller can identify BREAK character and the
imx_set_termios() can accept BRKINT set by users, but current existing
imx_rxint() can't pass BREAK character and TTY_BREAK to the tty layer
as other serial drivers do (8250.c omap_serial.c).

Here add code to handle BREAK character and pass it to tty layer.

To detect error occurrence, i use URXD_ERR to replace (URXD_OVRRUN |
URXD_FRMERR | ...) because any kind of error occurs, URXD_ERR will
always be set to 1.

I put the URXD_BRK to the first place to check since when BREAK error
occurs, not only URXD_BRK is set to 1, but also URXD_PRERR and
URXD_FRMERR are all set to 1. This arrangement can filter out fake
parity and frame errors when BREAK error occurs.

Signed-off-by: Hui Wang <jason77.wang@gmail.com>
Acked-by: Sascha Hauer <s.hauer@pengutronix.de>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-08-24 15:27:59 -07:00
Greg Kroah-Hartman
9a234349de Revert "tty: serial8250: add helpers for the DesignWare 8250"
This reverts commit 6b1a98d1c4.

It causes a build error that needs to be resolved differently.

Cc: Alan Cox <alan@linux.intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Jamie Iles <jamie@jamieiles.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-08-24 15:25:49 -07:00
Greg Kroah-Hartman
0b37004dd0 Revert "tty: of_serial: add support for the DesignWare 8250"
This reverts commit 14a8d47d4e.

It causes a build error that needs to be resolved differently.

Cc: Alan Cox <alan@linux.intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Jamie Iles <jamie@jamieiles.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-08-24 15:24:54 -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
Jamie Iles
14a8d47d4e tty: of_serial: add support for the DesignWare 8250
Support the DesignWare 8250 by a new compatible string and registering
the DesignWare helpers.  If the registration of the helpers fails, then
continue as a normal 8250 as we may still get some useful debug out.

Cc: Alan Cox <alan@linux.intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Jamie Iles <jamie@jamieiles.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-08-23 10:54:19 -07:00
Jamie Iles
6b1a98d1c4 tty: serial8250: add helpers for the DesignWare 8250
The Synopsys DesignWare 8250 is an 8250 that has an extra interrupt that
gets raised when writing to the LCR when busy.  To handle this we need
special serial_out, serial_in and handle_irq methods.  Add a new
function serial8250_use_designware_io() that configures a uart_port with
these accessors.

Cc: Alan Cox <alan@linux.intel.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Jamie Iles <jamie@jamieiles.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-08-23 10:54:19 -07:00
Jamie Iles
4834d02897 tty: serial8250: remove UPIO_DWAPB{,32}
Now that platforms can override the port IRQ handler and the only user
of these UPIO modes has been converted over, kill off UPIO_DWAPB and
UPIO_DWAPB32.

Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Jamie Iles <jamie@jamieiles.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-08-23 10:53:00 -07:00
Jamie Iles
583d28e92f tty: serial8250: allow platforms to override irq handler
Some ports (e.g. Synopsys DesignWare 8250) have special requirements for
handling the interrupts.  Allow these platforms to specify their own
interrupt handler that will override the default.
serial8250_handle_irq() is provided so that platforms can extend the IRQ
handler rather than completely replacing it.

Signed-off-by: Jamie Iles <jamie@jamieiles.com>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-08-23 10:52:59 -07:00
Thomas Abraham
88bb4ea14c serial: samsung: Add unified interrupt handler for s3c64xx and later SoC's
s3c64xx and later SoC's include the interrupt mask and pending registers
in the uart controller, unlike the s3c24xx SoC's which have these registers
in the interrupt controller. When the mask and pending registers are part
of the uart controller, a unified interrupt handler can handle the tx/rx
interrupt. With this, the static reservation of interrupt numbers for the
uart tx/rx/err interrupts in the linux irq space is not required and
simplifies adding device tree support.

Suggested-by: Grant Likely <grant.likely@secretlab.ca>
CC: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Thomas Abraham <thomas.abraham@linaro.org>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-08-23 10:48:31 -07:00
Sonic Zhang
47918f0558 serial:bfin_uart: Put TX IRQ in individual platform resource.
Serial TX IRQ is not RX IRQ plus 1 in some blackfin chips.
Give individual platform resources to both TX and RX irqs.

Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-08-23 10:48:31 -07:00
Sonic Zhang
0c6967b5a0 serial:blackfin: rename Blackfin serial driver to bfin_uart.c
bfin_5xx.c is not a general name for all Blackfin chips.

Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-08-23 10:47:05 -07:00
Sonic Zhang
bb7e58f896 serial:blackfin: Correct coding style in bfin serial driver.
Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-08-23 10:42:57 -07:00
Jiri Slaby
906cbe1364 TTY: remove tty_locked
We used it really only serial and ami_serial. The rest of the
callsites were BUG/WARN_ONs to check if BTM is held. Now that we
pruned tty_locked from both of the real users, we can get rid of
tty_lock along with __big_tty_mutex_owner.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Cc: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-08-23 10:34:07 -07:00
Jiri Slaby
6a3e492b6d TTY: serial, remove tasklet for tty_wakeup
tty_wakeup can be called from any context. So there is no need to have
an extra tasklet for calling that. Hence save some space and remove
the tasklet completely.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-08-23 10:34:06 -07:00
Jiri Slaby
e150c4ccbe TTY: msm_serial, remove unneeded console set
It doesn't make sense to set console to uart_port in console->setup.
At that time the console is set by uart_add_one_port already.

The call chain looked like:
uart_add_one_port()
  uport->cons = drv->cons;   <= once
  uart_configure_port()
    register_console()
     console->setup()
       port->cons = co;      <= second time

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-08-23 10:34:05 -07:00
Jiri Slaby
1f33a51d97 TTY: serial, remove BTM from wait_until_sent
During the BKL removal process, the BKL was switched to tty_lock
(BTM). Now we should start pruning the BTM further. Let's start with
wait_until_sent of the serial layer. This will allow us to switch to
the tty port helpers and thus clean it up much.

In wait_until_sent there are some uport members accessed, but neither
of them is protected by BTM at the location they are set ('=>' means
function call):
* uport->fifosize (set in tty_ioctl => uart_ioctl => uart_set_info)
* uport->type (set in add_one_port prior to tty_register_device)
* uport->timeout (set usually in tty_ioctl => tty_mode_ioctl =>
  tty_set_termios => uart_set_termios => uart_change_speed =>
  uport->ops->set_termios => uart_update_timeout)
* call to uport->ops->tx_empty()

If the tx_empty hook needs some lock to protect accesses to registers,
it should take &uport->lock spinlock like 8250 does. Otherwise there
still might be races e.g. with ISRs.

This should also fix the issue Andreas is seeing (BTM in comparison to
BKL doesn't have any hidden functionality like unlocking during
sleeping).

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
References: https://lkml.org/lkml/2011/5/25/562
Cc: Alan Cox <alan@linux.intel.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Cc: Andreas Bombe <aeb@debian.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-08-23 10:34:05 -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
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