The drivers/tty/serial dir is already getting rather busy.
Relocate the 8250 related drivers to their own subdir to
reduce the clutter.

Note that sunsu.c is not included in this move -- it is
8250-like hardware, but it does not use any of the existing
infrastructure -- and does not depend on SERIAL_8250.
Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

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>

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

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>

Fixes below compilation warning.

drivers/tty/serial/omap-serial.c: In function 'serial_omap_irq':
drivers/tty/serial/omap-serial.c:228:29: warning: 'ch' may be used uninitialized in this function [-Wuninitialized]

Fix below sparse warning.

drivers/tty/serial/omap-serial.c:392:52: warning: incorrect type in argument 2 (different signedness)
drivers/tty/serial/omap-serial.c:392:52:    expected int *status
drivers/tty/serial/omap-serial.c:392:52:    got unsigned int *<noident>
Reported-by: NKevin Hilman <khilman@ti.com>
Signed-off-by: NGovindraj.R <govindraj.raja@ti.com>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de> (for drivers/tty changes)
Signed-off-by: NKevin Hilman <khilman@ti.com>

Omap_uart_can_sleep function blocks system wide low power state until
uart is active remove this func and add qos requests to prevent
MPU from transitioning.

Keep qos request to default value which will allow MPU to transition
and while uart baud rate is available calculate the latency value
from the baudrate and use the same to hold constraint while uart clocks
are enabled, and if uart is auto-idled the constraint is updated with
default constraint value allowing MPU to transition.

Qos requests are blocking notifier calls so put these requests to
work queue, also the driver uses irq_safe version of runtime API's
and callbacks can be called in interrupt disabled context.
So to avoid warn on slow path warning while using qos update
API's from runtime callbacks use the qos_work_queue.

During bootup the runtime_resume call backs might not be called and runtime
callback gets called only after uart is idled by setting the autosuspend
timeout. So qos_request from runtime resume callback might not activated during
boot if uart baudrate is calculated during bootup for console uart, so schedule
the qos_work queue once we calc_latency while configuring the uart port.

Flush and complete any pending qos jobs in work queue while suspending.
Signed-off-by: NGovindraj.R <govindraj.raja@ti.com>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de> (for drivers/tty changes)
Signed-off-by: NKevin Hilman <khilman@ti.com>

When using DMA there are two timeouts defined. The first timeout,
rx_timeout, is really a polling rate in which software polls the
DMA status to see if the DMA has finished. This is necessary for
the RX side because we do not know how much data we will receive.
The secound timeout, RX_TIMEOUT, is a timeout after which the
DMA will be stopped if no more data is received. To make this
clearer, rename rx_timeout as rx_poll_rate and rename the
function serial_omap_rx_timeout() to serial_omap_rxdma_poll().

The OMAP-Serial driver defines an RX_TIMEOUT of 3 seconds that is
used to indicate when the DMA for UART can be stopped if no more
data is received. The value is a global definition that is applied
to all instances of the UART.

Each UART may be used for a different purpose and so the timeout
required may differ. Make this value configurable for each UART so
that this value can be optimised for power savings.
Signed-off-by: NJon Hunter <jon-hunter@ti.com>
Signed-off-by: NGovindraj.R <govindraj.raja@ti.com>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de> (for drivers/tty changes)
Signed-off-by: NKevin Hilman <khilman@ti.com>

The following UART parameters are defined within the UART driver:

1). Whether the UART uses DMA (dma_enabled), by default set to 0
2). The size of dma buffer (set to 4096 bytes)
3). The time after which the dma should stop if no more data is received.
4). The auto suspend delay that will be passed for pm_runtime_autosuspend
    where uart will be disabled after timeout

Different UARTs may be used for different purpose such as the console,
for interfacing bluetooth chip, for interfacing to a modem chip, etc.
Therefore, it is necessary to be able to customize the above settings
for a given board on a per UART basis.

This change allows these parameters to be configured from the board file
and allows the parameters to be configured for each UART independently.

If a board does not define its own custom parameters for the UARTs, then
use the default parameters in the structure "omap_serial_default_info".
The default parameters are defined to be the same as the current settings
in the UART driver to avoid breaking the UART for any cuurnelty supported
boards. By default, make all boards use the default UART parameters.
Signed-off-by: NDeepak K <deepak.k@ti.com>
Signed-off-by: NJon Hunter <jon-hunter@ti.com>
Signed-off-by: NGovindraj.R <govindraj.raja@ti.com>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de> (for drivers/tty changes)
Signed-off-by: NKevin Hilman <khilman@ti.com>

From the runtime callbacks enable hwmod wakeups for uart which will
internally enable io-pad wakeups for uarts if they have rx-pad pins
set as wakeup capabale.

Use the io-ring wakeup mechanism after uart clock gating and leave
the PM_WKST set for uart to default reset values cleanup the
code in serial.c which was handling PM_WKST reg.
Irq_chaing(PRM_DRIVER) is used to wakeup uart after uart clocks are gated
using pad wakeup mechanism.
Signed-off-by: NGovindraj.R <govindraj.raja@ti.com>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de> (for drivers/tty changes)
Signed-off-by: NKevin Hilman <khilman@ti.com>

Move the errata handling mechanism from serial.c to omap-serial file
and utilise the same func in driver file.

Errata i202, i291 are moved to be handled with omap-serial
Moving the errata macro from serial.c file to driver header file
as from on errata will be handled in driver file itself.
Corrected errata id from chapter reference 2.15 to errata id i291.

Removed errata and dma_enabled fields from omap_uart_state struct
as they are no more needed with errata handling done within omap-serial.
Signed-off-by: NGovindraj.R <govindraj.raja@ti.com>
Acked-by: NAlan Cox <alan@linux.intel.com>
Acked-by: NGreg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: NKevin Hilman <khilman@ti.com>

Avoid unconditional context restore every time we gate uart
clocks. Check whether context loss happened based on which
we can context restore uart regs from uart_port structure.
Signed-off-by: NGovindraj.R <govindraj.raja@ti.com>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de> (for drivers/tty changes)
Signed-off-by: NKevin Hilman <khilman@ti.com>

Remove the uart reset function which is configuring the
TX empty irq which can now be handled within omap-serial driver.
Signed-off-by: NGovindraj.R <govindraj.raja@ti.com>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de> (for drivers/tty changes)
Signed-off-by: NKevin Hilman <khilman@ti.com>

Add missing uart regs to uart_port structure which can be used in
context restore. Store dll, dlh, mdr1, scr, efr, lcr, mcr reg values
into uart_port structure while configuring individual port in termios
function.
Signed-off-by: NGovindraj.R <govindraj.raja@ti.com>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de> (for drivers/tty changes)
Signed-off-by: NKevin Hilman <khilman@ti.com>

Remove context save function from serial.c and move context restore
function to omap-serial. Remove all regs stored in omap_uart_state
for contex_save/restore, reg read write funcs used in context_save/restore,
io_addresses populated for read/write funcs.

Clock gating mechanism was done in serial.c and had no info on uart state
thus we needed context save and restore in serial.c
With runtime conversion and clock gating done within uart driver
context restore can be done from regs value available from uart_omap_port
structure.
Signed-off-by: NGovindraj.R <govindraj.raja@ti.com>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de> (for drivers/tty changes)
Signed-off-by: NKevin Hilman <khilman@ti.com>

Adapts omap-serial driver to use pm_runtime API's.
Use runtime runtime API's to handle uart clocks and obtain
device_usage statics. Set runtime API's usage to irq_safe so that
we can use get_sync from irq context. Auto-suspend for port specific
activities and put for reg access. Moving suspend/resume hooks
to dev_pm_ops structure and bind with config_suspend to avoid any
compilation warning if config_suspend is disabled.

By default uart autosuspend delay is set to -1 to avoid character loss
if uart's are autoidled and woken up on rx pin.

After boot up UART's can be autoidled by setting autosuspend delay from sysfs.

echo 3000 > /sys/devices/platform/omap/omap_uart.X/power/autosuspend_delay_ms
X=0,1,2,3 for UART1/2/3/4. Number of uarts available may vary across omap_soc.

Also if uart is not wakeup capable we can prevent runtime autosuspend by
forbiding runtime.
Signed-off-by: NGovindraj.R <govindraj.raja@ti.com>
Acked-by: NAlan Cox <alan@linux.intel.com>
Acked-by: NGreg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: NKevin Hilman <khilman@ti.com>

The mapbase (start_address), membase(io_remap cookie) part of
pdata struct omap_uart_port_info are removed as this should be
derived within driver.
Signed-off-by: NGovindraj.R <govindraj.raja@ti.com>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de> (for drivers/tty changes)
Signed-off-by: NKevin Hilman <khilman@ti.com>

Currently we use a shared irq handler to identify uart activity and then
trigger a timer. By default the timeout value is zero and can be set or
modified from sysfs. If there was no uart activity for the period set
through sysfs, the timer will expire and call timer handler this will
set a flag can_sleep using which decision to gate uart clocks can be taken.

Since the clock gating mechanism is outside the uart driver, we currently
use this mechanism. In preparation to runtime implementation for omap-serial
driver we can cleanup this mechanism and use runtime API's to gate uart clocks.

Removes the following:
* timer related info from local uart_state struct
* the code used to set timeout value from sysfs.
* irqflags used to set shared irq handler.
* un-used function omap_uart_check_wakeup.
Signed-off-by: NGovindraj.R <govindraj.raja@ti.com>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de> (for drivers/tty changes)
Signed-off-by: NKevin Hilman <khilman@ti.com>

Blackfin uart supports automatic CTS trigger when hardware flow control is enabled.
No need to start and top tx in CTS interrupt. So, remote ASYNC_CTS_FLOW flag.
Signed-off-by: NSonic Zhang <sonic.zhang@analog.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>