devpts operations are protected by inode mutexes and dentry
refcounting. There is no need to hold BTM.
Signed-off-by: NJiri Slaby <jslaby@suse.cz>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The code looks like:
if (tty->driver->subtype == PTY_TYPE_MASTER) {
  ...
  if (tty->driver == ptm_driver)

But the second if is superfluous because only the ptm_driver is of
PTY_TYPE_MASTER subtype.

Also we can remove the #if now because devpts_pty_kill is defined as
an empty function for non-CONFIG_UNIX98_PTYS configs.
Signed-off-by: NJiri Slaby <jslaby@suse.cz>
Acked-by: NAlan Cox <alan@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Use the helper in the rest of the tty drivers. This is a simple
replacement.
Signed-off-by: NJiri Slaby <jslaby@suse.cz>
Acked-by: NAlan Cox <alan@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

There are currently many cut&paste copies of what
tty_driver_install_tty does when custom ->install method is not
provided. Let's get rid of the copies and create a helper with this
setup code.
Signed-off-by: NJiri Slaby <jslaby@suse.cz>
Cc: Havard Skinnemoen <hskinnemoen@google.com>
Acked-by: NAlan Cox <alan@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The receive FIFO wakeup latency estimate in the omap-serial driver is
three orders of magnitude too small.  This effectively prevents the
MPU from going to a low-power state when CONFIG_CPU_IDLE=y.  This is a
major power management regression and masks some other FIFO-related
bugs in the driver.

Fix by correcting the most egregious problem in the RX wakeup latency
estimate.  There are several other flaws in the estimator; these will
be fixed by a separate patch series intended for 3.4.

The difference in low-power states with this patch can be observed via
debugfs in pm_debug/count.

This estimate does not have any effect when CONFIG_CPU_IDLE=n.
Signed-off-by: NPaul Walmsley <paul@pwsan.com>
Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
Cc: Alan Cox <alan@linux.intel.com>
Acked-by: NGovindraj.R <govindraj.raja@ti.com>
Reviewed-by: NKevin Hilman <khilman@ti.com>
Tested-by: NKevin Hilman <khilman@ti.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Prevent OMAP UARTs from going idle while they are still transferring
data in PIO mode.  This works around an oversight in the OMAP UART
hardware present in OMAP34xx and earlier: an idle UART won't send a
wakeup when the TX FIFO threshold is reached.  This causes long delays
during data transmission when the MPU powerdomain enters a low-power
mode.  The MPU interrupt controller is not able to respond to
interrupts when it's in a low-power state, so the TX buffer is not
refilled until another wakeup event occurs.

This fix changes the erratum i291 DMA idle workaround.  Rather than
toggling between force-idle and no-idle, it will toggle between
smart-idle and no-idle.  The important part of the workaround is the
no-idle part, so this shouldn't result in any change in behavior.

This fix should work on all OMAP UARTs.  Future patches intended for
the 3.4 merge window will make this workaround conditional on a
"feature" flag, and will use the OMAP36xx+ TX event wakeup support.

Thanks to Kevin Hilman <khilman@ti.com> for mentioning the erratum i291
workaround, which led to the development of this approach.
Signed-off-by: NPaul Walmsley <paul@pwsan.com>
Cc: Alan Cox <alan@linux.intel.com>
Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
Acked-by: NGovindraj.R <govindraj.raja@ti.com>
Reviewed-by: NKevin Hilman <khilman@ti.com>
Tested-by: NKevin Hilman <khilman@ti.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

In the (default) PIO mode, use a one-byte RX FIFO threshold.  The OMAP
UART IP blocks do not appear to be capable of waking the system under
an RX timeout condition.  Since the previous RX FIFO threshold was 16
bytes, this meant that omap-serial.c did not become aware of any
received data until all those bytes arrived or until another UART
interrupt occurred.  This made the serial console and presumably other
serial applications (GPS, serial Bluetooth) unusable or extremely
slow.  A 1-byte RX FIFO threshold also allows the MPU to enter a
low-power consumption state while waiting for the FIFO to fill.

This can be verified using the serial console by comparing the
behavior when "0123456789abcde" is pasted in from another window, with
the behavior when "0123456789abcdef" is pasted in.  Since the former
string is less than sixteen bytes long, the string is not echoed for
some time, while the latter string is echoed immediately.

DMA operation is unaffected by this patch.

Thanks to Russell King - ARM Linux <linux@arm.linux.org.uk> for some
additional information on the standard behavior of the RX timeout
event, which was used to improve this commit description.
Signed-off-by: NPaul Walmsley <paul@pwsan.com>
Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
Cc: Govindraj Raja <govindraj.r@ti.com>
Cc: Alan Cox <alan@linux.intel.com>
Cc: Russell King <linux@arm.linux.org.uk>
Reviewed-by: NKevin Hilman <khilman@ti.com>
Tested-by: NKevin Hilman <khilman@ti.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

We transform the offenders into a test of irq <= 0 which will be ok while
the ARM people get their platform sorted. Once that is done (or in a while
if they don't do it anyway) then we will change them all to !irq checks.

For arch specific drivers that are already using NO_IRQ = 0 we just test
against zero so we don't need to re-review them later.
Signed-off-by: NAlan Cox <alan@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Signed-off-by: NUwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Let's move this stuff to the better place, where we can account pty right in
tty-indexes managing code.
Signed-off-by: NKonstantin Khlebnikov <khlebnikov@openvz.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

cleanup hack added in v2.6.27-3203-g15582d36

comment from that patch:

: pty: If the administrator creates a device for a ptmx slave we should not error
:
: The open path for ptmx slaves is via the ptmx device. Opening them any
: other way is not allowed. Vegard Nossum found that previously this was not
: the case and mknod foo c 128 42; cat foo would produce nasty diagnostics
:
: Signed-off-by: Alan Cox <alan@redhat.com>
: Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

devpts_get_tty() returns non-null only for inodes on devpts, but there is no
inodes for master-devices, /dev/ptmx (/dev/pts/ptmx) is the only way to open them.
Thus we can completely forbid lookup for master-devices and eliminate that hack in
tty_init_dev() because tty_open() will get EIO from tty_driver_lookup_tty().
Signed-off-by: NKonstantin Khlebnikov <khlebnikov@openvz.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

module_param(bool) used to counter-intuitively take an int.  In
fddd5201 (mid-2009) we allowed bool or int/unsigned int using a messy
trick.

It's time to remove the int/unsigned int option.  For this version
it'll simply give a warning, but it'll break next kernel version.
Acked-by: NMauro Carvalho Chehab <mchehab@redhat.com>
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

del_timer_sync() acquires its own lock and doesn't have to be nested
within the spinlock of sport->port.lock in imx_set_termios(),  which
will cause potential deadlock.  Fix this by moving it outside.

Cc: Fabio Estevam <fabio.estevam@freescale.com>
Cc: Shawn Guo <shawn.guo@linaro.org>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: NEric Miao <eric.miao@linaro.org>
Signed-off-by: NShawn Guo <shawn.guo@linaro.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

These methods are invoked if the iMX uart is used in conjuction with kgdb during
early boot.  In order to access the UART without the interrupts, the kernel uses
the basic polling methods for IO with the device.  With these methods
implemented, it is now possible to enable kgdb during early boot over serial.
Signed-off-by: NSaleem Abdulrasool <compnerd@compnerd.org>
Signed-off-by: NDirk Behme <dirk.behme@gmail.com>
CC: Sascha Hauer <s.hauer@pengutronix.de>
CC: Fabio Estevam <festevam@gmail.com>
CC: Uwe Kleine-Koenig <u.kleine-koenig@pengutronix.de>
CC: linux-serial@vger.kernel.org
CC: Alan Cox <alan@linux.intel.com>
Signed-off-by: NShawn Guo <shawn.guo@linaro.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Factor out the uart save/restore functionality instead of
having the same code several times in the driver.
Signed-off-by: NDirk Behme <dirk.behme@gmail.com>
CC: Saleem Abdulrasool <compnerd@compnerd.org>
CC: Sascha Hauer <s.hauer@pengutronix.de>
CC: Fabio Estevam <festevam@gmail.com>
CC: Uwe Kleine-Koenig <u.kleine-koenig@pengutronix.de>
CC: linux-serial@vger.kernel.org
CC: Alan Cox <alan@linux.intel.com>
Signed-off-by: NShawn Guo <shawn.guo@linaro.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

When the uart device is instantiated by dt but dt doesn't provide an
alias then better let probing fail instead of falling back to an
unrelated device id used for the line number and no platform data.
Signed-off-by: NUwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: NShawn Guo <shawn.guo@linaro.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

A quick look at of_alias_get_id shows that in the error case it returns
-ENODEV, too, but still it's better style to propagate the value as is.
Signed-off-by: NUwe Kleine-König <u.kleine-koenig@pengutronix.de>
Cc: Shawn Guo <shawn.guo@linaro.org>
Cc: Alan Cox <alan@linux.intel.com>
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: Jeremy Kerr <jeremy.kerr@canonical.com>
Cc: Jason Liu <jason.hui@linaro.org>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Acked-by: NJason Liu <jason.hui@linaro.org>
Signed-off-by: NShawn Guo <shawn.guo@linaro.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Allow UART to be a source for wakeup from low power mode.

Tested on a MX27PDK by doing:

echo enabled > /sys/devices/platform/imx21-uart.0/tty/ttymxc0/power/wakeup

echo mem > /sys/power/state

and then pressing a key in the console will wakeup the sytem.
Suggested-by: NShawn Guo <shawn.guo@freescale.com>
Signed-off-by: NFabio Estevam <fabio.estevam@freescale.com>
Tested-by: NRichard Zhao <richard.zhao@freescale.com>
Signed-off-by: NShawn Guo <shawn.guo@linaro.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This driver was copied from the original 8250 driver and hence
got the DEC alpha errata workaround.  But the workaround is ugly
and we don't really want it in any more places than it absolutely
needs to be.  Obviously ARCH=m32r means ARCH != alpha, so just
remove the references to the ALPHA_KLUDGE_MCR define.
Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Patch to fix a spinlock lockup in the driver that sometimes happens when the
tasklet starts.
Signed-off-by: NClaudio Scordino <claudio@evidence.eu.com>
Signed-off-by: NDave Bender <codehero@gmail.com>
Tested-by: NDave Bender <codehero@gmail.com>
Acked-by: NNicolas Ferre <nicolas.ferre@atmel.com>
Acked-by: NAlan Cox <alan@linux.intel.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Virtual console unicode translation map leaks with following
message when enable kmemleak:

unreferenced object 0xeb5ec450 (size 192):
  comm "setfont", pid 665, jiffies 4294899028 (age 3696.220s)
  hex dump (first 32 bytes):
    e0 5b 9d eb 00 00 00 00 00 00 00 00 80 b9 ea eb  .[..............
    b0 5a 9d eb 00 00 00 00 00 00 00 00 00 00 00 00  .Z..............
  backtrace:
    [<c1533f8c>] kmemleak_alloc+0x3c/0xa0
    [<c114acc2>] kmem_cache_alloc_trace+0xe2/0x250
    [<c13498e8>] con_clear_unimap+0x78/0xd0
    [<c1345552>] vt_ioctl+0x1562/0x1d00
    [<c133aa00>] tty_ioctl+0x230/0x7c0
    [<c1171519>] do_vfs_ioctl+0x79/0x2d0
    [<c11717df>] sys_ioctl+0x6f/0x80
    [<c156601f>] sysenter_do_call+0x12/0x38
    [<ffffffff>] 0xffffffff
unreferenced object 0xeb9d5be0 (size 128):
  comm "setfont", pid 660, jiffies 4294899030 (age 3696.212s)
  hex dump (first 32 bytes):
    60 c2 a6 eb 50 c8 a6 eb c0 54 9d eb 80 59 9d eb  `...P....T...Y..
    90 53 9d eb 60 52 9d eb 60 92 9b eb 00 00 00 00  .S..`R..`.......
  backtrace:
    [<c1533f8c>] kmemleak_alloc+0x3c/0xa0
    [<c114acc2>] kmem_cache_alloc_trace+0xe2/0x250
    [<c134938c>] con_insert_unipair+0x7c/0x150
    [<c1349f8c>] con_set_unimap+0x15c/0x1f0
    [<c13456fb>] vt_ioctl+0x170b/0x1d00
    [<c133aa00>] tty_ioctl+0x230/0x7c0
    [<c1171519>] do_vfs_ioctl+0x79/0x2d0
    [<c11717df>] sys_ioctl+0x6f/0x80
    [<c156601f>] sysenter_do_call+0x12/0x38
    [<ffffffff>] 0xffffffff

The leak caused by con_set_default_unimap() not correct free the old map.
Signed-off-by: NZeng Zhaoming <zengzm.kernel@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Signed-off-by: NUwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

both callers of device_get_devnode() are only interested in lower 16bits
and nobody tries to return anything wider than 16bit anyway.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Move invalidate_bdev, block_sync_page into fs/block_dev.c.  Export
kill_bdev as well, so brd doesn't have to open code it.  Reduce
buffer_head.h requirement accordingly.

Removed a rather large comment from invalidate_bdev, as it looked a bit
obsolete to bother moving.  The small comment replacing it says enough.
Signed-off-by: NNick Piggin <npiggin@suse.de>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

add support for 400Hv3, 410Hv3 and 800Hv3
Signed-off-by: NYegor Yefremov <yegorslists@googlemail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

The patch converts mxs-auart driver to clk_prepare/clk_unprepare by
using helper functions clk_prepare_enable/clk_disable_unprepare.
Signed-off-by: NShawn Guo <shawn.guo@linaro.org>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Alan Cox <alan@linux.intel.com>

Fix following warnings:

WARNING: drivers/tty/serial/built-in.o(.text+0x7370): Section mismatch in reference from the function grlib_apbuart_configure() to the variable .init.data:apbuart_match
The function grlib_apbuart_configure() references
the variable __initdata apbuart_match.
This is often because grlib_apbuart_configure lacks a __initdata
annotation or the annotation of apbuart_match is wrong.

+ 3 more warnings like this.

There is no guarantee that grlib_apbuart_of_driver.of_match_table
is only used at __init time - so drop the __initdata annotation.

grlib_apbuart_configure() is only used during __init so add __init
to this method too.
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>
Cc: Daniel Hellstrom <daniel@gaisler.com>
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

exynos4120_serial_drv_data is only defined when building with support
for Exynos4210 so use the already provided define to ensure that we
don't reference it when building for other SoCs.
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>
[kgene.kim@samsung.com: Fixed build warning]
Signed-off-by: NKukjin Kim <kgene.kim@samsung.com>

Add device tree based discovery support for Samsung's uart controller.

Cc: Ben Dooks <ben-linux@fluff.org>
Acked-by: NGrant Likely <grant.likely@secretlab.ca>
Signed-off-by: NThomas Abraham <thomas.abraham@linaro.org>
Signed-off-by: NKukjin Kim <kgene.kim@samsung.com>

With reset port, set clock and get clock functions in SoC specific extentions
being removed, only the driver probe is left over in these extensions. The
probe function itself can be merged into one and moved into the samsung common
serial driver. With driver probe also moved, all the SoC specific extentions
are no longer required and they are deleted.

Cc: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: NThomas Abraham <thomas.abraham@linaro.org>
Signed-off-by: NKukjin Kim <kgene.kim@samsung.com>

The port reset function in each of the platform specific extension performs
the same operations and hence all the reset port functions can be merged into
one and moved into the common samsung uart driver. The SoC specific port reset
functions are removed from SoC extensions.

Cc: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: NThomas Abraham <thomas.abraham@linaro.org>
Signed-off-by: NKukjin Kim <kgene.kim@samsung.com>

With clkdev based clock lookup support, the clock set and get operation
using clock names communicated between the samsung uart driver and the
SoC specific extension can be removed.

In addition to that, for each platform specific extension, add the
default clock selection, number of clock options for uart baud generator,
clock selection bit mask and shift values which is required by the
clkdev support in samsung uart driver.

The default clock selection value 'def_clk_sel' specifies the default clock
to be used as the source clock for baud rate generator in case the platform
code does not specify the same.

Cc: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: NThomas Abraham <thomas.abraham@linaro.org>
Signed-off-by: NKukjin Kim <kgene.kim@samsung.com>

With clkdev based clock lookup added to samsung serial driver, the use
of 'struct s3c24xx_uart_clksrc' to supply clock names in platform
data is removed from all the Samsung platform code.

Cc: Ben Dooks <ben-linux@fluff.org>
Cc: Ramax Lo <ramaxlo@gmail.com>
Cc: Vasily Khoruzhick <anarsoul@gmail.com>
Signed-off-by: NThomas Abraham <thomas.abraham@linaro.org>
Signed-off-by: NKukjin Kim <kgene.kim@samsung.com>

Instead of using clock names supplied in platform data, use a generic
clock name 'clk_uart_baud' to look up clocks. The platform code should
register clocks with the name 'clk_uart_baud' which can be used by the
baud rate generator. The clock lookup and selection of the best clock
as baud rate clock is reworked.

Platform code can specify the clocks that can be used as source for the
baud clock (as supported previously by passing names of clocks). A new
member is added to the platform data 'clk_sel' which holds a bit-field
value with each bit representing a baud source clock. If a bit at any
bit position is set, that clock is looked up to participate in the
selection of the baud clock source.

Cc: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: NThomas Abraham <thomas.abraham@linaro.org>
Signed-off-by: NKukjin Kim <kgene.kim@samsung.com>

s3c2440 uses fclk/n (fclk divided by n) clock as one of the possible clocks used
to generate the baud rate clock. The divider 'n' in this case can be logically
represented outside of the uart controller.

This patch creates a new clock by name "fclk_n" for s3c2440 based platforms to
represent the fclk/n clock in the platform code. This clock provides a get_rate
callback that checks the UCON0/1/2 registers to determine the clock rate. The
samsung uart driver would receive the "fclk_n" clock name as one of the possible
baud rate clock options and the driver need not determine clock rate of fclk/n.

Cc: Ben Dooks <ben-linux@fluff.org>
Cc: Vasily Khoruzhick <anarsoul@gmail.com>
Signed-off-by: NThomas Abraham <thomas.abraham@linaro.org>
Signed-off-by: NKukjin Kim <kgene.kim@samsung.com>

Add a pointer to the location of the platform data in the driver's private
data. When instantiated using device tree, pdev->dev->platform_data does not
necessarily point to a valid instance of platform data. The platform data
pointer in the driver's private data could be set to pdev->dev->platform_data
or platform data instance created from device tree.

Cc: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: NThomas Abraham <thomas.abraham@linaro.org>
Signed-off-by: NKukjin Kim <kgene.kim@samsung.com>

Adapt the driver to device tree and pass minimal platform
data from device tree needed for console boot.
No power management features will be suppported for now
since it requires more tweaks around OCP settings
to toggle forceidle/noidle/smartidle bits and handling
remote wakeup and dynamic muxing.
Signed-off-by: NRajendra Nayak <rnayak@ti.com>
Reviewed-by: NRob Herring <rob.herring@calxeda.com>
Signed-off-by: NTony Lindgren <tony@atomide.com>

Use a default clock speed of 48Mhz, instead of ending up with 0,
if platforms fail to specify a valid clock speed.
Signed-off-by: NRajendra Nayak <rnayak@ti.com>
Reviewed-by: NRob Herring <rob.herring@calxeda.com>
Signed-off-by: NTony Lindgren <tony@atomide.com>

With Device tree, pdev->id would no longer be Valid.
Hence get rid of all instances of its usage in the
driver. Device tree support for the driver is added
in subsequent patches.
Signed-off-by: NRajendra Nayak <rnayak@ti.com>
Reviewed-by: NRob Herring <rob.herring@calxeda.com>
Signed-off-by: NTony Lindgren <tony@atomide.com>

This patch reworks & simplifies pmac_zilog handling of suspend/resume,
essentially removing all the specific code in there and using the
generic uart helpers.

This required properly registering the tty as a child of the macio (or platform)
device, so I had to delay the registration a bit (we used to register the ports
very very early). We still register the kernel console early though.

I removed a couple of unused or useless flags as well, relying on the
core to not call us when asleep. I also removed the essentially useless
interrupt mutex, simplifying the locking a bit.

I removed some code for handling unexpected interrupt which should never
be hit and could potentially be harmful (causing us to access a register
on a powered off SCC). We diable port interrupts on close always so there
should be no need to drain data on a closed port.
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>