This patch unlocks the port lock before calling a serial_core API
and re-acquires the port lock after calling it.
This patch fixes a system freeze issue seen when the serial_core
API uart_write_wakeup() eventually attempts to acquire the port lock
already acquired by omap serial interrupt handler.
Tested-by: NShubhrajyoti D <shubhrajyoti@ti.com>
Signed-off-by: NRuchika Kharwar <ruchika@ti.com>
Signed-off-by: NPavan Savoy <pavan_savoy@ti.com>
Signed-off-by: NVijay Badawadagi <bvijay@ti.com>
Signed-off-by: NFelipe Balbi <balbi@ti.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

it makes no sense to mark our IRQ handler inline
since it's passed as a function pointer when
enabling the IRQ line.
Tested-by: NShubhrajyoti D <shubhrajyoti@ti.com>
Signed-off-by: NFelipe Balbi <balbi@ti.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Two functions:
omap_serial_fill_features_erratas() and
of_get_uart_port_info() are only called from probe().
Marking them as __devinit gives us another
oportunity to free some code after .init.text
is done.
Tested-by: NShubhrajyoti D <shubhrajyoti@ti.com>
Signed-off-by: NRuchika Kharwar <ruchika@ti.com>
Signed-off-by: NFelipe Balbi <balbi@ti.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

pm_runtime_enable() needs to be invoked before
pm_runtime_use_autosuspend(), and
pm_runtime_set_autosuspend_delay() functions.
Tested-by: NShubhrajyoti D <shubhrajyoti@ti.com>
Signed-off-by: NNishanth Menon <nm@ti.com>
Signed-off-by: NRuchika Kharwar <ruchika@ti.com>
Signed-off-by: NFelipe Balbi <balbi@ti.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

When we're running our hardirq handler, there's
not need to disable IRQs with spin_lock_irqsave()
because IRQs are already disabled. It also makes
no difference if we save or not IRQ flags.

Switch over to simple spin_lock/spin_unlock and
drop the "flags" variable.
Tested-by: NShubhrajyoti D <shubhrajyoti@ti.com>
Signed-off-by: NFelipe Balbi <balbi@ti.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

before removing the driver, let's make sure
to force device into a suspended state in order
to conserve power.
Tested-by: NShubhrajyoti D <shubhrajyoti@ti.com>
Acked-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: NFelipe Balbi <balbi@ti.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

if platform_get_drvdata() returns NULL, that's
quite a nasty bug on the driver which we want to
catch ASAP. Otherwise, that check is hugely
unneeded.
Tested-by: NShubhrajyoti D <shubhrajyoti@ti.com>
Acked-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: NFelipe Balbi <balbi@ti.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

by the time we call our first pm_runtme_get_sync()
after enable pm_runtime, our resume method might
be called. To avoid problems, we must make sure
that our dev->drvdata is set correctly before
our resume method gets called.
Tested-by: NShubhrajyoti D <shubhrajyoti@ti.com>
Acked-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: NFelipe Balbi <balbi@ti.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Everytime we're done using our TTY, we want
the pm timer to be reinitilized. By sticking
to pm_runtime_pm_autosuspend() we make sure
that this will always be the case.

The idea behind this patch is to make sure we
will always reinitialize the pm timer so that
we don't fall into a situation where pm_runtime_put()
expires right away (if timer was already about to
expire when we made the call to pm_runtime_put()).

While suspending right away wouldn't cause any
issues, reinitializing the pm timer can help us
avoiding unnecessary context save & restore
operations (which are somewhat expensive) if there's
another read/write/set_termios request coming right
after. IOW, we are trying to make sure UART is still
powered up while it's still under heavy usage.
Tested-by: NShubhrajyoti D <shubhrajyoti@ti.com>
Acked-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: NFelipe Balbi <balbi@ti.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

since all other IRQ types now do all necessary
checks inside their handlers, transmit_chars()
was the only one left expecting serial_omap_irq()
to check THRE for it. We can move THRE check to
transmit_chars() in order to make serial_omap_irq()
more uniform.
Tested-by: NShubhrajyoti D <shubhrajyoti@ti.com>
Acked-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: NFelipe Balbi <balbi@ti.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

receive_chars() was getting too big and too difficult
to follow. By splitting it into separate RDI and RSLI
handlers, we have smaller functions which are easy
to understand and only touch the pieces which they need
to touch.
Tested-by: NShubhrajyoti D <shubhrajyoti@ti.com>
Acked-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: NFelipe Balbi <balbi@ti.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

quite a few changes here, though they are
pretty obvious. In summary we're making sure
to detect which interrupt type we need to
handle before calling the underlying interrupt
handling procedure.
Tested-by: NShubhrajyoti D <shubhrajyoti@ti.com>
Acked-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: NFelipe Balbi <balbi@ti.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The current support is known to be broken and
a later patch will come re-adding it using
dma engine API.
Tested-by: NShubhrajyoti D <shubhrajyoti@ti.com>
Acked-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: NFelipe Balbi <balbi@ti.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The driver doesn't need to know about its platform_device.

Everything the driver needs can be done through the
struct device pointer. In case we need to use the
OMAP-specific PM function pointers, those can make
sure to find the device's platform_device pointer
so they can find the struct omap_device through
pdev->archdata field.
Tested-by: NShubhrajyoti D <shubhrajyoti@ti.com>
Acked-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: NFelipe Balbi <balbi@ti.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

These were reported in bugzilla long ago with a hack patch. Now we have a
proper patch for one we can do the rest.

Resolves-bug: https://bugzilla.kernel.org/show_bug.cgi?id=25102Signed-off-by: NAlan Cox <alan@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

In most of the time, the driver needs to check if the cts flow control
is enabled. But now, the driver checks the ASYNC_CTS_FLOW flag manually,
which is not a grace way. So add a new wraper function to make the code
tidy and clean.
Signed-off-by: NHuang Shijie <shijie8@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

this patch is in preparation to a few other changes
which will align on the prototype for function
pointers passed through pdata.

It also helps cleaning up the driver a little by
agregating checks for pdata in a single location.
Tested-by: NShubhrajyoti D <shubhrajyoti@ti.com>
Acked-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: NFelipe Balbi <balbi@ti.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

current code only works because struct uart_port
is the first member on the uart_omap_port structure.

If, for whatever reason, someone puts another
member as the first of the structure, that cast
won't work anymore. In order to be safe, let's use
a container_of() which, for now, gets optimized into
a cast anyway.
Tested-by: NShubhrajyoti D <shubhrajyoti@ti.com>
Acked-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: NFelipe Balbi <balbi@ti.com>
Acked-by: NTony Lindgren <tony@atomide.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This patch adds note about migration to driver SCCNXP in the code
of driver SC26XX and in MIPS SNI board initialization with example.
Signed-off-by: NAlexander Shiyan <shc_work@mail.ru>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This driver is a replacement for a SC26XX driver with a lot of
improvements and new features.
The main differences from the SC26XX driver:
- Removed dependency on MIPS. Driver can be used on any platform.
- Added support for SCC2681, SCC2691, SCC2692, SC28L91, SC28L92,
  SC28L202, SCC68681 and SCC68692 ICs.
- Using devm_-related functions.
- Improved error handling of serial port, improved FIFO handling.
- Ability to load multiple instances of drivers.

To avoid the possibility of regression, driver SC26XX left in the
system to confirm the stability of the driver on platforms where
it is being used.
Signed-off-by: NAlexander Shiyan <shc_work@mail.ru>
Acked-by: NAlan Cox <alan@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

To allow parport_serial to handle the card the same PCI ids are blacklisted
in 8250_pci.c using the existing software blacklist mechanism.

The blacklist array is also renamed because it now covers this new use
case.

Since the two serial ports are auto-detected as XScale instead of 16550A
clones, we also add a quirk to 8250_pci.c to skip autodetection and set the
correct port type.
Signed-off-by: NGianluca Anzolin <gianluca@sottospazio.it>
[Fold in fixes for the uart_8250 change]
Signed-off-by: NAlan Cox <alan@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Fixes the following errors and warnings:
ERROR: trailing whitespace
ERROR: return is not a function, parentheses are not required
WARNING: suspect code indent for conditional statements (32, 36)
Signed-off-by: NSachin Kamat <sachin.kamat@linaro.org>
Acked-by: NAlan Cox <alan@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Silences checkpatch warnings regarding use of printks.
Signed-off-by: NSachin Kamat <sachin.kamat@linaro.org>
Acked-by: NAlan Cox <alan@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

If the order of UART nodes is changed in the device tree, then tty dev
devices are attached to different serial ports causing the console to
be directed to a different physical serial port. The "serial" aliases
in the device tree should prevent this.

This patch ensures that the UART driver creates tty devices that
honour these aliases if a device tree is present.
Acked-by: NLinus Walleij <linus.walleij@linaro.org>
Reviewed-by: NWill Deacon <will.deacon@arm.com>
Acked-by: NRob Herring <rob.herring@calxeda.com>
Signed-off-by: NMatthew Leach <matthew.leach@arm.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This structure might have made sense many years ago, but at this
point it is only used in one specific driver, and referenced in
stale comments elsewhere.  Rather than change the sunsu.c driver,
simply move the struct to be within the exclusive domain of that
driver, so it won't get inadvertently picked up and used by other
serial drivers going forward.  The comments referencing the now
driver specific struct are updated accordingly.

Note that 8250.c has a struct that is similar in usage, with the
name serial8250_config; but is 100% independent and untouched here.

Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>
Acked-by: NAlan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The addition of 8250-like entities continues to grow, while this
driver has a snapshot of a select few common 8250 UARTs.  So it
has no need to grow with the new additions, since it calls out
its own (largely historic) static list which does not grow.

Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>
Acked-by: NAlan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The struct serial_uart_config is hardly used at all, and the
use case like this one are somewhat needless.  Remove the
trivial usage so that we can remove serial_uart_config.

Since the type field isn't really used at all, we also delete
the initialization and references of it here as well.

Cc: Hirokazu Takata <takata@linux-m32r.org>
Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>
Acked-by: NAlan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

These error paths are used more often now after deep changes to the
clock code and pinctrl is still new for imx. So help debugging and give
clues in the boot log.
Signed-off-by: NUwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

We want them split so that we can call them from setserial functionality
where we copy to/from user space and do the locking, but also from sysfs
where in future we'll want to came them within a sysfs context.
Signed-off-by: NAlan Cox <alan@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

devm free functions should not have to be explicitly used.

A semantic match that finds this problem is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@
@@

(
* devm_kfree(...);
|
* devm_free_irq(...);
|
* devm_iounmap(...);
|
* devm_release_region(...);
|
* devm_release_mem_region(...);
)
// </smpl>
Signed-off-by: NJulia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Tested on a custom MPC5200B-board using some fancy industrial protocol.
Verified that MPC512x has identical bits, so should work there as well.
Signed-off-by: NWolfram Sang <w.sang@pengutronix.de>
Acked-by: NAnatolij Gustschin <agust@denx.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

There is no reason to explicitly call devm_kfree
in probe or remove functions.
Signed-off-by: NEmil Goode <emilgoode@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The gpiochip_remove function may fail to remove a gpio_chip
if any GPIOs are still requested. This patch informs the caller
of such a senario.

Sparse is warning because the function prototype has a
__must_check annotation.

Sparse warning:
drivers/tty/serial/max310x.c:1223:18: warning:
	ignoring return value of ‘gpiochip_remove’,
	declared with attribute warn_unused_result
	[-Wunused-result]
Signed-off-by: NEmil Goode <emilgoode@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Use the wrapper functions, so we can directly pass a struct
platfrom_device.
Signed-off-by: NTobias Klauser <tklauser@distanz.ch>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

the driver's module init and exit functions can be replaced
with module_spi_driver as they do
only spi_register_driver and spi_unregister_driver in module's init and exit
paths.
Signed-off-by: NDevendra Naga <develkernel412222@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Clk_prepare_enable and clk_disable_unprepare combine clk_prepare and
clk_enable, and clk_disable and clk_unprepare.  The9 make the code more
concise, and ensure that clk_unprepare is called when clk_enable fails.

A simplified version of the semantic patch that introduces calls to these
functions is as follows: (http://coccinelle.lip6.fr/)

// <smpl>
@@
expression e;
@@

- clk_prepare(e);
- clk_enable(e);
+ clk_prepare_enable(e);

@@
expression e;
@@

- clk_disable(e);
- clk_unprepare(e);
+ clk_disable_unprepare(e);
// </smpl>
Signed-off-by: NJulia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

kdb <-> kgdb transitioning does not work properly with this UART
driver because the get character routine loops indefinitely as opposed
to returning NO_POLL_CHAR per the expectation of the KDB I/O driver
API.

The symptom is a kernel hang when trying to switch debug modes.

Cc: Alan Cox <alan@linux.intel.com>
Signed-off-by: NJason Wessel <jason.wessel@windriver.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Without checking if the auart supports the hardware flow control or not,
the old mxs_auart_set_mctrl() asserted the RTS pin blindly.

This will causes the auart receives wrong data in the following case:
   The far-end has already started the write operation, and wait for
the auart asserts the RTS pin. Then the auart starts the read operation,
but mxs_auart_set_mctrl() may be called before we set the RTSCTS in the
mxs_auart_settermios(). So the RTS pin is asserted in a wrong situation,
and we get the wrong data in the end.

This bug has been catched when I connect the mx23(DTE) to the mx53(DCE).

This patch also replaces the AUART_CTRL2_RTS with AUART_CTRL2_RTSEN.
We should use the real the hardware flow control, not the software-controled
hardware flow control.
Signed-off-by: NHuang Shijie <b32955@freescale.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This driver is a replacement for a MAX3107 driver with a lot of
improvements and new features.
The main differences from the old version:
- Using the regmap.
- Using devm_XXX-related functions.
- The use of threaded IRQ with IRQF_ONESHOT flag allows the driver to
  the hardware that supports only level IRQ.
- Improved error handling of serial port, improved FIFO handling,
  improved hardware & software flow control.
- Advanced flags allows turn on RS-485 mode (Auto direction control).
- Ability to load multiple instances of drivers.
- Added support for MAX3108.
- GPIO support.
- Driver is quite ready for adding I2C support and support other ICs
  with compatible registers set (MAX3109, MAX14830).
Signed-off-by: NAlexander Shiyan <shc_work@mail.ru>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

OMAP hardware doesn't provide a phyisical DTR line, but
some configurations may need a DTR line which tracks whether
the device is open or not.

So allow a gpio to be configured as the DTR line.
Signed-off-by: NNeilBrown <neilb@suse.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>