The meaning of CONFIG_EMBEDDED has long since been obsoleted; the option
is used to configure any non-standard kernel with a much larger scope than
only small devices.

This patch renames the option to CONFIG_EXPERT in init/Kconfig and fixes
references to the option throughout the kernel.  A new CONFIG_EMBEDDED
option is added that automatically selects CONFIG_EXPERT when enabled and
can be used in the future to isolate options that should only be
considered for embedded systems (RISC architectures, SLOB, etc).

Calling the option "EXPERT" more accurately represents its intention: only
expert users who understand the impact of the configuration changes they
are making should enable it.
Reviewed-by: NIngo Molnar <mingo@elte.hu>
Acked-by: NDavid Woodhouse <david.woodhouse@intel.com>
Signed-off-by: NDavid Rientjes <rientjes@google.com>
Cc: Greg KH <gregkh@suse.de>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Robin Holt <holt@sgi.com>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

When working in RS485 mode, the atmel_serial driver keeps RTS high after
the initialization of the serial port.  It goes low only after the first
character has been sent.

[akpm@linux-foundation.org: simplify code]
Signed-off-by: NClaudio Scordino <claudio@evidence.eu.com>
Signed-off-by: NArkadiusz Bubala <arkadiusz.bubala@gmail.com>
Tested-by: NArkadiusz Bubala <arkadiusz.bubala@gmail.com>
Cc: Nicolas Ferre <nicolas.ferre@atmel.com>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This fixes up the port_rx_irq_mask() REIE flag definition as well as a
debug printk blowing up on the SCSCR_INIT having gone away.
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

Swap device and driver names in serial/samsung.c
Signed-off-by: NDarius Augulis <augulis.darius@gmail.com>
Cc: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: NKukjin Kim <kgene.kim@samsung.com>

Rather than maintain Kconfig entries where people have to enter raw
numbers and hardcode lists of addresses/pins in the driver itself,
push it all to platform resources.  This lets us simplify the driver,
the Kconfig, and gives board porters greater flexibility.

In the process, we need to also start supporting the early platform
interface.  Not a big deal, but it causes the patch to be bigger than
a simple resource relocation.

All the Blackfin boards already have their resources updated and in
place for this change.
Signed-off-by: NSonic Zhang <sonic.zhang@analog.com>
Acked-by: NGreg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: NMike Frysinger <vapier@gentoo.org>

commit 35c64e5d (drivers: serial: apbuart: Handle OF failures
gracefully) missed that the modified grlib_apbuart_configure()
function is called from apbuart_console_init() as well.

Fix the fallout.
Reported-by: NStephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

ST Micro variants has some specific dma burst threshold compensation,
which allows them to make better use of a DMA controller.  Add support
to set this up.

Based on a patch from Linus Walleij.
Acked-by: NLinus Walleij <linus.walleij@stericsson.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Add DMA engine support for transmit to the PL011 driver.  Based on a
patch from Linus Walliej, with the following changes:

- remove RX DMA support.  As PL011 doesn't give us receive timeout
  interrupts, we only get notified of received data when the RX DMA
  has completed.  This rather sucks for interactive use of the TTY.

- remove abuse of completions.  Completions are supposed to be for
  events, not to tell what condition buffers are in.  Replace it with
  a simple 'queued' bool.

- fix locking - it is only safe to access the circular buffer with the
  port lock held.

- only map the DMA buffer when required - if we're ever behind an IOMMU
  this helps keep IOMMU usage down, and also ensures that we're legal
  when we change the scatterlist entry length.

- fix XON/XOFF sending - we must send XON/XOFF characters out as soon
  as possible - waiting for up to 4095 characters in the DMA buffer
  to be sent first is not acceptable.

- fix XON/XOFF receive handling - we need to stop DMA when instructed
  to by the TTY layer, and restart it again when instructed to.  There
  is a subtle problem here: we must not completely empty the circular
  buffer with DMA, otherwise we will not be notified of XON.

- change the 'enable_dma' flag into a 'using DMA' flag, and track
  whether we can use TX DMA by whether the channel pointer is non-NULL.
  This gives us more control over whether we use DMA in the driver.

- we don't need to have the TX DMA buffer continually allocated for
  each port - instead, allocate it when the port starts up, and free
  it when it's shut down.  Update the 'using DMA' flag if we get
  the buffer, and adjust the TTY FIFO size appropriately.

- if we're going to use PIO to send characters, use the existing IRQ
  based functionality rather than reimplementing it.  This also ensures
  we call uart_write_wakeup() at the appropriate time, otherwise we'll
  stall.

- use DMA engine helper functions for type safety.

- fix init when built as a module - we can't have to initcall functions,
  so we must settle on one.  This means we can eliminate the deferred
  DMA initialization.

- there is no need to terminate transfers on a failed prep_slave_sg()
  call - nothing has been setup, so nothing needs to be terminated.
  This avoids a potential deadlock in the DMA engine code
  (tasklet->callback->failed prepare->terminate->tasklet_disable
   which then ends up waiting for the tasklet to finish running.)

- Dan says that the submission callback should not return an error:
  | dma_submit_error() is something I should have removed after commit
  | a0587bcf "ioat1: move descriptor allocation from submit to prep" all
  | errors should be notified by prep failing to return a descriptor
  | handle.  Negative dma_cookie_t values are only returned by the
  | dma_async_memcpy* calls which translate a prep failure into -ENOMEM.
  So remove the error handling at that point.  This also solves the
  potential deadlock mentioned in the previous comment.
Acked-by: NLinus Walleij <linus.walleij@stericsson.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

As the DMA support introduces a separate interrupt-time callback, our
interrupt handler will not be the only handler which takes the port
lock, so we need to ensure that IRQs are disabled.  We must use the
_irqsave variant so we don't inadvertently enable interrupts.
Acked-by: NLinus Walleij <linus.walleij@stericsson.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

With DMA support, we need to tell the TTY subsystem that the DMA buffer
is the size of the FIFO, otherwise things like tty_wait_until_sent()
will time out too early.  Keep (and use) the hardware value separately
from the port->fifosize.

This was part of a larger patch from Linus Walleij, with a little
modification.
Acked-by: NLinus Walleij <linus.walleij@stericsson.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Rather than copying all vendor data into the port structure, copy
just that which is frequently used, and keep a pointer to the
remaining vendor data structure.  This makes it easier to add
vendor quirks in the future.
Acked-by: NLinus Walleij <linus.walleij@stericsson.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

The error flags weren't being cleared upon UART startup, which
can cause problems when we add DMA support.  It's good practice
to ensure that these flags are cleared anyway, so let's do so.

This was part of a larger patch from Linus Walleij.
Acked-by: NLinus Walleij <linus.walleij@stericsson.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Include the revision number of the PL011 primecell in the boot-time
port printk to allow proper identification of the peripheral.
Acked-by: NLinus Walleij <linus.walleij@stericsson.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Signed-off-by: NDaniel Hellstrom <daniel@gaisler.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NDaniel Hellstrom <daniel@gaisler.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Some OF drivers could likely be used on non-powerpc OF based platforms,
so fix the kconfig depends to be CONFIG_OF instead of CONFIG_PPC_OF.

Compile tested on ARM and sparc.
Signed-off-by: NRob Herring <rob.herring@calxeda.com>
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>

On PPC, of_irq.h gets implicitly included, but on other platforms
it does not.
Signed-off-by: NRob Herring <rob.herring@calxeda.com>
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>

The apbuart driver depends on OF and relies on everything being
available. So if it's probed on a platform which has OF support, but
no device tree is available it crashes. Triggered by the upcoming x86
OF support in randconfig testing.

Further it's inconsistent vs. the probing and exiting from the
of_match loop.

Make it robust and consistent:

 - check the availablility of OF nodes before dereferencing
 - return -ENODEV when the device tree lookup fails
 - return -ENODEV when no uart port configuration is found
 - return -ENODEV when invalid uart port configuration is found

Remove the enum_done check while at it. Driver init functions are only
called once. Remove the pointless vendor and device queries as well.

Reported-by: Ingo Molnar <mingo.elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: Kristoffer Glembo <kristoffer@gaisler.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

To avoid unbalanced IRQ wake disable, ensure that wakeups are disabled
only when wakeups have been successfully enabled.
Tested on OMAP3630SDP/ZOOM3.
Signed-off-by: NGovindraj.R <govindraj.raja@ti.com>
Reported-by: NPaul Walmsley <paul@pwsan.com>
Cc: Santosh Shilimkar <santosh.shilimkar@ti.com>
Acked-by: NKevin Hilman <khilman@deeprootsystems.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Fix the following warnings
drivers/serial/pch_uart.c: In function ‘dma_handle_rx’:
drivers/serial/pch_uart.c:685:24: warning: cast from pointer to integer of different size
drivers/serial/pch_uart.c: In function ‘dma_handle_tx’:
drivers/serial/pch_uart.c:778:23: warning: cast from pointer to integer of different size
drivers/serial/pch_uart.c: In function ‘pch_uart_init_port’:
drivers/serial/pch_uart.c:1289:20: warning: cast to pointer from integer of different size
drivers/serial/pch_uart.c: In function ‘pch_uart_exit_port’:
drivers/serial/pch_uart.c:1328:2: warning: cast from pointer to integer of different size
Signed-off-by: NTomoya MORINAGA <tomoya-linux@dsn.okisemi.com>
Reported-by: NGreg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

The commit 111c1823 (kgdboc: reset
input devices (keyboards) when exiting debugger) introduced a
regression in early debugging such that you get a kernel oops on
continue (with the go command) if you boot a kernel with:

    earlyprintk=vga ekgdboc=kbd kgdbwait

The restore kgdboc_restore_input() routine schedules work for the
purpose of sending key release events for any keys that were in the
depressed state prior to entering the kernel debugger.  A simple fix
to the crash is to not invoke the schedule_work() if the kernel
system_state is anything other than SYSTEM_RUNNING.
Signed-off-by: NJason Wessel <jason.wessel@windriver.com>
Acked-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>
Reviewed-by: NSergei Shtylyov <sshtylyov@mvista.com>

I have found a bug in 8250.c driver which causes that 16550A uart FIFOs
are not turned on during initialization if they are manually configured
by setserial. UART is then working only as plain 16450 without FIFOs. On
systems with higher interrupt latency this causes buffer overruns and
loss of received data when using higher communication speeds.

I'm working for a company which produces industrial computers. These
devices typically contain high number (8 or more) of traditional 16550A
uarts - we use TL16C554A chips, but that is not much relevant. UARTs are
connected to the CPU by ISA bus (Celeron based devices) or LPC bus (Atom
based devices).

In the Linux the UARTs are using standard 8250.c driver and are
initialized using setserial command:
setserial /dev/ttyS4 uart 16550A port 0x3E0 irq 10 baud_base 115200

This executes the UART initialization through serial8250_startup()
function. At the beginning of the function up->capabilities is
initialized from uart_config:
 up->capabilities = uart_config[up->port.type].flags;
Please note that neither up->port.fifosize nor up->tx_loadsz is
initialized here!!

Later in the same function serial8250_clear_fifos() is called and
disables FIFOs. The above comment says that they will be reenabled in
set_termios (they won't ...)

After serial8250_startup() the serial8250_set_termios() is called. In
this function the following check fails because up->port.fifosize is
zero because it is not initialized correctly.

        if (up->capabilities & UART_CAP_FIFO && up->port.fifosize > 1) {
                if (baud < 2400)
                        fcr = UART_FCR_ENABLE_FIFO | UART_FCR_TRIGGER_1;
                else
                        fcr = uart_config[up->port.type].fcr;
        }

fcr variable remains zero and in the end the FCR register is set to zero
which results in disabled FIFOs even if the UART type is 16550A. This is
also true for other types of UARTs with FIFOs.

If the UART is autoconfigured via 'setserial /dev/ttySx autoconfig' then
port.fifosize and tx_loadsz are initialized correctly in the
autoconfig() function and the UART is working correctly then.

I checked the source codes and I can say that this bug is present in
2.6.x series of kernels for a couple of years. Namely I can confirm its
presence in 2.6.16.57, 2.6.32.24 and 2.6.36.1 (tested all of them on our
hardware).

I think it was not noticed before because not many people use manually
configured non PNP UARTs on ISA/LPC bus these days. Also the data loss
caused by buffer overruns occures only if  IRQ latency is higher then
time needed to receive one character on given communication speed.
For example our hardware looses received characters only if the UARTs
are connected throught LPC bus with SERIRQ (serial IRQ transport) and
not if they are connected to ISA bus because LPC SERIRQ has higher
interrupt latency then parallel ISA interupt lines.

Here is the patch to correct the bug created against 2.6.36.1:
Signed-off-by: NOndrej Puzman <puzman@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Some platforms contain a Synopsys DesignWare APB UART that is attached
to a 32-bit APB bus where sub-word accesses are not allowed. Add a new
IO type (UPIO_DWAPB32) that performs 32 bit acccesses to the UART.

v2:
	- don't test for 32 bit in the output fast path, provide a
	  separate dwabp32_serial_out() function. Refactor
	  dwabp_serial_out() so that we can reuse the LCR saving
	  code.
v3:
	- rebased on top of "8250: use container_of() instead of
	  casting"
Signed-off-by: NJamie Iles <jamie@jamieiles.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

The 8250 driver structure uart_8250_port took advantage of the fact
that the struct uart_port was the first member of its structure and
used an explicit cast to convert to the derived class. Replace the
explicit casts with container_of() for safety and clarity.
Signed-off-by: NJamie Iles <jamie@jamieiles.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

The kgdb invokes the poll_put_char and poll_get_char when communicating
with the host. This patch also changes the initialization order because the
kgdb will check at the very beginning, if there is a valid serial
driver.
Signed-off-by: NCosmin Cojocar <cosmin.cojocar@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

The dma_request_channel/dma_release_channel interfaces are not
built when DMADEVICES is not enabled, so make the driver depend on
DMADEVICES.  Also, the help text says that the driver enables & uses
PCH_DMA, which is not enabled, so select that.

ERROR: "__dma_request_channel" [drivers/serial/pch_uart.ko] undefined!
ERROR: "dma_release_channel" [drivers/serial/pch_uart.ko] undefined!
Signed-off-by: NRandy Dunlap <randy.dunlap@oracle.com>
Cc: Tomoya MORINAGA <tomoya-linux@dsn.okisemi.com>
Reported-by: NZimny Lech <napohybelskurwysynom2010@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

IS_ERR() already implies unlikely(), so it can be omitted here.
Signed-off-by: NTobias Klauser <tklauser@distanz.ch>
Signed-off-by: NDavid Brown <davidb@codeaurora.org>

Previous baud rate setting code only has been tested with 3.5M/9600/
115200/230400/460800 bps, and recently we got a 3M bps device to test,
which needs to modify current MUL register setting, and with this
patch 2.5M/2M/1.5M/1M/0.5M should also work as they just use a MUL
value scale down from 3M's.

Also got some reference register setting from silicon guys for
different baud rates, which tries to keep the pre-scalar register value
to 16.
Signed-off-by: NFeng Tang <feng.tang@intel.com>
Cc: stable <stable@kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

If tty_register_driver() failed then tty_driver is still alive.
Free it with put_tty_driver().
Signed-off-by: NVasiliy Kulikov <segoon@openwall.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

If second request_irq() failed then the first IRQ must be freed in
error handling code.
Signed-off-by: NVasiliy Kulikov <segoon@openwall.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

UART driver of Intel EG20T(Topcliff) PCH

Intel EG20T PCH is the platform controller hub that is going to be used in
Intel's general embedded platform. All IO peripherals in
Intel EG20T PCH are actually devices sitting on AMBA bus.
Intel EG20T PCH has UART I/F. Using this I/F, it is able to access system
devices connected to UART.
Signed-off-by: NTomoya MORINAGA <tomoya-linux@dsn.okisemi.com>
Acked-by: NAlan Cox <alan@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This patch adds support for the PCI UART on the ce4100.
Signed-off-by: NDirk Brandewie <dirk.brandewie@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Access to some registers depends on register access mode
Three different modes are available for OMAP (at least)
• Operational mode     LCR_REG[7] = 0x0
• Configuration mode A LCR_REG[7] = 0x1 and LCR_REG[7:0]! = 0xBF
• Configuration mode B LCR_REG[7] = 0x1 and LCR_REG[7:0]  = 0xBF

Define access modes and remove redefinitions and magic numbers
in serial drivers (and later in bluetooth driver).
Signed-off-by: NAndrei Emeltchenko <andrei.emeltchenko@nokia.com>
Acked-by: NGovindraj.R <govindraj.raja@ti.com>
Acked-by: NGreg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: NTony Lindgren <tony@atomide.com>

Define MDR1 register serial definitions used in serial and
bluetooth drivers.
Change magic number to ones defined in serial_reg for omap1/2
serial driver.
Remove redefined MDR1 register definitions in omap-serial driver.
Signed-off-by: NAndrei Emeltchenko <andrei.emeltchenko@nokia.com>
Acked-by: NG, Manjunath Kondaiah <manjugk@ti.com>
Acked-by: NGovindraj.R <govindraj.raja@ti.com>
Acked-by: NGreg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: NTony Lindgren <tony@atomide.com>

This patch adds initial support for Renesas SH-Mobile AG5.

At this point the AG5 CPU support is limited to the ARM
core, SCIF serial and a CMT timer together with L2 cache
and the GIC. The AG5EVM board also supports Ethernet.

Future patches will add support for GPIO, INTCS, CPGA
and platform data / driver updates for devices such as
IIC, LCDC, FSI, KEYSC, CEU and SDHI among others.

The code in entry-macro.S will be cleaned up when the
ARM IRQ demux code improvements have been merged.

Depends on the AG5EVM mach-type recently registered but
not yet present in arch/arm/tools/mach-types.

As the AG5EVM board comes with 512MiB memory it is
recommended to turn on HIGHMEM.

Many thanks to Yoshii-san for initial bring up.
Signed-off-by: NMagnus Damm <damm@opensource.se>
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

The big kernel lock has been removed from all these files at some point,
leaving only the #include.

Remove this too as a cleanup.
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

While trying to debug a cpu-hotplug issue I noticed printk() stopped
working once the cpu got marked offline, since the 8250 serial console
doesn't have any per-cpu resources the CON_ANYTIME bit is the safe and
documented way to make it work again.
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Noted by Stephen Rothwell
Signed-off-by: NAlan Cox <alan@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Correct the KConfig as noted by Greg.
Signed-off-by: NAlan Cox <alan@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

The printout for the type should be just "5xxx", so 512x users won't
wonder why they have a mpc52xx-type UART.
Signed-off-by: NWolfram Sang <w.sang@pengutronix.de>
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>