Busy loops that poll on a register should call cpu_relax().  On some
architectures, it can lower CPU power consumption or yield to a
hyperthreaded twin processor.  It also serves as a compiler barrier,
so it can replace barrier() calls.
Signed-off-by: Timur Tabi <timur@codeaurora.org>
Reviewed-by: Dave Martin <Dave.Martin@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

In datasheet, Modem Status Register MSR[4-7] reflect the modem pins
CTS/DSR/RI/CD signal state.
Signed-off-by: Wills Wang <wills.wang@live.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

In all functions other than atmel_serial_probe_fifos,
atmel_serial_probe, and atmel_console_init, the name "port" is used to
refer to an instance of struct uart_port. In many of these functions,
"atmel_port" is used to refer to an instance of struct atmel_uart_port.

We make the use of the name "port" consistent by making
atmel_serial_probe_fifos, atmel_serial_probe, and atmel_console_init
use "atmel_port" to refer to an instance of struct atmel_uart_port
instead of the previous name of "port".
Signed-off-by: Jaeden Amero <jaeden.amero@ni.com>
Signed-off-by: Kyle Roeschley <kyle.roeschley@ni.com>
Acked-by: Karthik Manamcheri <karthik.manamcheri@ni.com>
[nicolas.ferre@atmel.com: fix typo in variable, adapt to newer kernel]
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Starting with sama5d2, the new UART revision has an hardware timer. So, add it
to the IP detection code and set the "has_hw_timer" property for it.
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Reported-by: David Mosberger <davidm@egauge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

No functional change is associated with this patch.

A driver property depends on the Atmel serial IP revision. This property
is the way the rx timeout is handled: by an hardware or software timer.
So, change this property name and setup code so that it's easier to understand
and more future proof as the distinction of USART vs. UART is blurrier on newer
SoCs.
Variable names and debug comments are also adapted to make this code more obvious.
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Some UART HW has a single register combining UART_DLL/UART_DLM
(this was probably forgotten in the change that introduced the
callbacks, commit b32b19b8)

Fixes: b32b19b8 ("[SERIAL] 8250: set divisor register correctly ...")
Signed-off-by: Sebastian Frias <sf84@laposte.net>
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

It's old, messy and mostly unmaintained.
Remove it as suggested by Peter Hurley and Alan.
Signed-off-by: Frederik Völkel <frederik.voelkel@fau.de>
Signed-off-by: Lukas Braun <lukas.braun@fau.de>
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Constifies psc_ops structures in tty's serial
port driver since they are not modified after
their initialization.

Detected and found using Coccinelle.
Suggested-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Aya Mahfouz <mahfouz.saif.elyazal@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Direct call to readl()/writel() is checked against iotype
and in case of UPIO_MEM32BE we use ioread32be()/iowrite32be()
instead of them.
Signed-off-by: Noam Camus <noamc@ezchip.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Add support for UPIO_MEM32BE in addition to UPIO_MEM32.

For big endian we use 2 new accessors similar to little endian,
called dw8250_serial_out32be() and dw8250_serial_in32be().
Signed-off-by: Noam Camus <noamc@ezchip.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

With the help of Heikki we take common code that
makes sure LCR write wasn't ignored and put it in new function called
dw8250_check_lcr(). This function serves 3 serial_out routines:
dw8250_serial_out(), dw8250_serial_out32(), and dw8250_serial_outq().

This patch only brings better code reuse.
Signed-off-by: Noam Camus <noamc@ezchip.com>
Cc: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Use software emulated RS485 direction control to provide RS485 API
existed in omap_serial driver. Note that 8250_omap issues interrupt
on shift register empty which is single prerequesite for using software
emulated RS485.
Signed-off-by: Matwey V. Kornilov <matwey@sai.msu.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Implementation of software emulation of RS485 direction handling is based
on omap_serial driver.
Before and after transmission RTS is set to the appropriate value.

Note that before calling serial8250_em485_init() the caller has to
ensure that UART will interrupt when shift register empty. Otherwise,
emultaion cannot be used.

Both serial8250_em485_init() and serial8250_em485_destroy() are
idempotent functions.
Signed-off-by: Matwey V. Kornilov <matwey@sai.msu.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Software RS485 emultaion is to be added in the following commit.
serial8250_start_tx() will need to refer serial8250_stop_rx().
Move serial8250_stop_rx() in front of serial8250_start_tx() in order
to avoid function forward declaration.
Signed-off-by: Matwey V. Kornilov <matwey@sai.msu.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

struct uart_sio_port has a lots of unused members. Some of them are
set to some constant but never read. Remove all those.

This includes removal of uart_ops->pm handler as we never handle pm
(pm was never set).
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

DEBUG_AUTOCONF is unused.

Switch DEBUG_INTR to pr_debug. This is only enabled with DEBUG or
dynamic debug when explicitly asked for.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

The only variables in old_serial_port are port and irq. So make
old_serial_port contain only those two and move the initialization of
the rest to the place where old_serial_port is actually read.

Also get rid of SERIAL_PORT_DFNS. It is ugly and having the
initializer where it belongs makes more sense. Finally, use already
defined UART_NR in the loop.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

The only needed information from the header is struct old_serial_port.
Move it to m32r_sio.c, make it const and anonymous. And kill the rest
from the header as it is dead stuff.

Given m32r_sio_suspend_port and m32r_sio_resume_port are local to
m32r_sio.c and unused, kill them from .c too.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

This is a remnant from the dark age. Nobody uses the macro now, so
remove.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Chris Zankel <chris@zankel.net>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: <linux-xtensa@linux-xtensa.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Since check_name and check_resources return only 0/1, switch them to
bool/true/false.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Make modem_names and base static const.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

c_iflag and c_cflag are set, but unused. Remove.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

There is a chain of up to 4 nested ifs in init and remove functions.
Instead, make the code linear and use goto's to handle failures.

Remove unneeded cast from mpsc_release_port by referencing pi->port
directly. And finally, use dev_dbg instead of pr_debug given we have
dev->dev node.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

When mpsc_routing_base, sdma_intr_base, mpsc_base, sdma_base, and
brg_base are mapped, they are never unmapped. The condition in the
free paths is always 'if (!XXX_base) { unmap }'. Fix it by inverting
the condition.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Add DT earlycon for 8250_omap driver. This boot console is included
for kernels built with CONFIG_SERIAL_EARLYCON=y, CONFIG_OF=y,
CONFIG_SERIAL_8250_OMAP=y, and CONFIG_OF_EARLY_FLATTREE=y.

This boot console is enabled with the command line option "earlycon"
(without "=<name>...") when the DT 'stdout-path' property matches a
compatible uart. For example,

/ {
   chosen {
        stdout-path = "serial0:115200";
   };

   ....

   aliases {
        serial0 = &uart0;
   };

   ....

   ocp : ocp {
        uart0 : serial@44e09000 {
             compatible = "ti,omap3-uart";
        }
   };
};
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Earlycon may fail to initialize for a variety of reasons, most of
which log the default early param message. If the stdout-path node is
not found, log the path which was not found (and suppress the
default early param message).
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

earlycon initializes struct uart_port::regshift to the correct
value for UPIO_MEM32 already. Use the port field rather than
hard-coded value.

This enables broader support for various i/o access methods in
8250 earlycon (eg., omap8250 earlycon).
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Output the earlycon "driver" from the just-parsed console 'name'
and 'index' fields.

NB: ->mapbase is a resource_size_t so use %pa format specifier
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Refactor the command line earlycon banner into earlycon_init() so
both earlycon startup methods output an info banner.
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Cleanup the early DT/earlycon separation; remove the 'addr' parameter
from of_setup_earlycon() and get the uart phys addr directly with a
new wrapper function, of_flat_dt_translate_addr(). Limit
fdt_translate_address() to file scope.
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Read the optional "reg-offset", "reg-shift", "reg-io-width" and endianness
properties and initialize the respective struct uart_port field if found.

NB: These bindings are common to several drivers and the values merely
indicate the default value; the registering earlycon setup() method can
simply override the values if required.
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Pass-through any options string in the 'stdout-path' property to the
earlycon "driver" setup.
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Use the console name embedded in the OF earlycon table by the
OF_EARLYCON_DECLARE() macro to initialize the struct console 'name'
and 'index' fields.
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Properly initialize the struct console 'name' and 'index' fields for
the registering earlycon. For earlycons w/o trailing numerals, the
index is set to 0; otherwise, the index is set to the value of the
trailing numeral. For example, the 'exynos4210' earlycon name == "exynos"
and index == 4210. Earlycons with embedded numerals will have all
non-trailing numerals as part of the name; for example, the 's3c2412'
earlycon name == "s3c" and index == 2412.

This ackward scheme was initially added for the uart8250 earlycon;
adopt this scheme for the other earlycon "drivers".

Introduce earlycon_init() which performs the string scanning and
initializes the name and index fields; encapsulate the other console
field initializations within.
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Use a single common table of struct earlycon_id for both command line
and devicetree. Re-define OF_EARLYCON_DECLARE() macro to instance a
unique earlycon declaration (the declaration is only guaranteed to be
unique within a compilation unit; separate compilation units must still
use unique earlycon names).

The semantics of OF_EARLYCON_DECLARE() is different; it declares an
earlycon which can matched either on the command line or by devicetree.
EARLYCON_DECLARE() is semantically unchanged; it declares an earlycon
which is matched by command line only. Remove redundant instances of
EARLYCON_DECLARE().

This enables all earlycons to properly initialize struct console
with the appropriate name and index, which improves diagnostics and
enables direct earlycon-to-console handoff.
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

DT earlycon is only supported for CONFIG_OF_EARLY_FLATTREE=y; exclude
of_setup_earlycon() if not defined.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

We want the tty/serial fixes in here as well to make merges easier.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Pull USB driver fixes from Greg KH:
 "Here are some small USB fixes and new device ids for 4.5-rc2.  Nothing
  major here, full details are in the shortlog, and all of these have
  been in linux-next successfully"

* tag 'usb-4.5-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
  USB: option: fix Cinterion AHxx enumeration
  USB: mxu11x0: fix memory leak on usb_serial private data
  USB: serial: ftdi_sio: add support for Yaesu SCU-18 cable
  USB: serial: option: Adding support for Telit LE922
  USB: serial: visor: fix crash on detecting device without write_urbs
  USB: visor: fix null-deref at probe
  USB: cp210x: add ID for IAI USB to RS485 adaptor
  usb: hub: do not clear BOS field during reset device
  cdc-acm:exclude Samsung phone 04e8:685d
  usb: cdc-acm: send zero packet for intel 7260 modem
  usb: cdc-acm: handle unlinked urb in acm read callback

Pull tty/serial fixes from Greg KH:
 "Here are some small tty/serial driver fixes for 4.5-rc2.

  They resolve a number of reported problems (the ioctl one specifically
  has been pointed out by numerous people) and one patch adds some new
  device ids for the 8250_pci driver.  All have been in linux-next
  successfully"

* tag 'tty-4.5-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
  serial: 8250_pci: Add Intel Broadwell ports
  staging/speakup: Use tty_ldisc_ref() for paste kworker
  n_tty: Fix unsafe reference to "other" ldisc
  tty: Fix unsafe ldisc reference via ioctl(TIOCGETD)
  tty: Retry failed reopen if tty teardown in-progress
  tty: Wait interruptibly for tty lock on reopen