Request_irq() should be _after_ h/w programming, otherwise an
interrupt could be triggered and in-progress before the h/w has been
setup.
Reported-by: NPeter Hurley <peter@hurleysoftware.com>
Signed-off-by: NSoren Brinkmann <soren.brinkmann@xilinx.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Move RX-related IRQ handling into a helper function.
Fixes a problem where every char received after a parity or frame error
in the current isr will also be tagged as a parity or frame error.
Signed-off-by: NSoren Brinkmann <soren.brinkmann@xilinx.com>
Reviewed-by: NPeter Hurley <peter@hurleysoftware.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Shutting down the UART port can happen while console operations are in
progress. Holding the port lock serializes these operations and avoids
the UART HW to be disabled in the middle of console prints.
Signed-off-by: NSoren Brinkmann <soren.brinkmann@xilinx.com>
Reviewed-by: NPeter Hurley <peter@hurleysoftware.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The RX path in the interrupt handler released a lock unnecessarily.
Signed-off-by: NSoren Brinkmann <soren.brinkmann@xilinx.com>
Reviewed-by: NPeter Hurley <peter@hurleysoftware.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The startup function is supposed to initialize the UART for receiving.
Hence, don't enable the TX part. Also, protect HW accesses with the port
lock.
Signed-off-by: NSoren Brinkmann <soren.brinkmann@xilinx.com>
Reviewed-by: NPeter Hurley <peter@hurleysoftware.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

When shutting down the UART, clear the interrupt status register. Bits
in the ISR are cleared by writing them as '1'.
Signed-off-by: NSoren Brinkmann <soren.brinkmann@xilinx.com>
Reviewed-by: NPeter Hurley <peter@hurleysoftware.com>
Reviewed-by: NMoritz Fischer <moritz.fischer@ettus.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Restarting the transmitter even if the circ buffer is empty may be
necessary to push out remaining data when the port is restarted after
being stopped.

Cc: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: NSoren Brinkmann <soren.brinkmann@xilinx.com>
Reviewed-by: NPeter Hurley <peter@hurleysoftware.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Instead of disabling the IRQ, use the spin lock to serialize accesses to
the HW. This protects the driver from interference of non-IRQ callbacks
with each other and makes the driver more consistent in its
serialization method.
Signed-off-by: NSoren Brinkmann <soren.brinkmann@xilinx.com>
Reviewed-by: NPeter Hurley <peter@hurleysoftware.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Non-functional, formatting changes to ease reading the code.
Signed-off-by: NSoren Brinkmann <soren.brinkmann@xilinx.com>
Reviewed-by: NPeter Hurley <peter@hurleysoftware.com>
Reviewed-by: NMoritz Fischer <moritz.fischer@ettus.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

"earlyprintk" is architecture specific option.
General "earlycon" option support is much better.
Signed-off-by: NYoshinori Sato <ysato@users.sourceforge.jp>
[uli: preserve other SCSCR bits when asserting RE and TE]
Signed-off-by: NUlrich Hecht <ulrich.hecht+renesas@gmail.com>
[geert: rewording, #ifdef rework]
Signed-off-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Considering that pci_pericom_setup(()'s only difference to
pci_default_setup() is the setting of the uartclk field, and taking
into account that this field already gets taken care of by having the
base_baud field filled in the pci_boards[] entries, there's no need
for both the function and the quirks table entry.
Signed-off-by: NJan Beulich <jbeulich@suse.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Use to_pci_dev() instead of open-coding it.
Signed-off-by: NGeliang Tang <geliangtang@163.com>
Reviewed-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The pl011 driver has gone back and forth on the definition of the
ZTE specific variation of the hardware definitions, but the
current state is that the vendor definition is left in place
yet unused:

drivers/tty/serial/amba-pl011.c:190:27: warning: 'vendor_zte' defined but not used [-Wunused-variable]

I don't know what the plan forward is to get this code to work,
but the current behavior is a bit annoying as we get a warning
whenever we build this driver.

This patch does not help us to make it work, but at least
shuts up the warning.
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Fixes: 7ec75871 ("tty: amba-pl011: add support for ZTE UART (EXPERIMENTAL)")
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

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: NTimur Tabi <timur@codeaurora.org>
Reviewed-by: NDave Martin <Dave.Martin@arm.com>
Signed-off-by: NGreg 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: NWills Wang <wills.wang@live.com>
Signed-off-by: NGreg 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: NJaeden Amero <jaeden.amero@ni.com>
Signed-off-by: NKyle Roeschley <kyle.roeschley@ni.com>
Acked-by: NKarthik Manamcheri <karthik.manamcheri@ni.com>
[nicolas.ferre@atmel.com: fix typo in variable, adapt to newer kernel]
Signed-off-by: NNicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: NGreg 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: NNicolas Ferre <nicolas.ferre@atmel.com>
Reported-by: NDavid Mosberger <davidm@egauge.net>
Signed-off-by: NGreg 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: NNicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: NGreg 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: NSebastian Frias <sf84@laposte.net>
Reviewed-by: NPeter Hurley <peter@hurleysoftware.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

It's old, messy and mostly unmaintained.
Remove it as suggested by Peter Hurley and Alan.
Signed-off-by: NFrederik Völkel <frederik.voelkel@fau.de>
Signed-off-by: NLukas Braun <lukas.braun@fau.de>
Reviewed-by: NPeter Hurley <peter@hurleysoftware.com>
Signed-off-by: NGreg 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: NJulia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: NAya Mahfouz <mahfouz.saif.elyazal@gmail.com>
Signed-off-by: NGreg 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: NNoam Camus <noamc@ezchip.com>
Signed-off-by: NGreg 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: NNoam Camus <noamc@ezchip.com>
Signed-off-by: NGreg 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: NNoam Camus <noamc@ezchip.com>
Cc: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NGreg 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: NMatwey V. Kornilov <matwey@sai.msu.ru>
Signed-off-by: NGreg 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: NMatwey V. Kornilov <matwey@sai.msu.ru>
Signed-off-by: NGreg 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: NMatwey V. Kornilov <matwey@sai.msu.ru>
Signed-off-by: NGreg 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: NJiri Slaby <jslaby@suse.cz>
Signed-off-by: NGreg 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: NJiri Slaby <jslaby@suse.cz>
Signed-off-by: NGreg 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: NJiri Slaby <jslaby@suse.cz>
Signed-off-by: NGreg 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: NJiri Slaby <jslaby@suse.cz>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

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

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

c_iflag and c_cflag are set, but unused. Remove.
Signed-off-by: NJiri Slaby <jslaby@suse.cz>
Signed-off-by: NGreg 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: NJiri Slaby <jslaby@suse.cz>
Signed-off-by: NGreg 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: NJiri Slaby <jslaby@suse.cz>
Signed-off-by: NGreg 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: NPeter Hurley <peter@hurleysoftware.com>
Signed-off-by: NGreg 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: NRob Herring <robh@kernel.org>
Signed-off-by: NPeter Hurley <peter@hurleysoftware.com>
Signed-off-by: NGreg 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: NRob Herring <robh@kernel.org>
Signed-off-by: NPeter Hurley <peter@hurleysoftware.com>
Signed-off-by: NGreg 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: NRob Herring <robh@kernel.org>
Signed-off-by: NPeter Hurley <peter@hurleysoftware.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>