Commit Graph

154 Commits

Author SHA1 Message Date
Peter Hurley
2bb785169e serial: core: Fix iotype userspace breakage
commit 3ffb1a8193 ("serial: core: Add big-endian iotype")
re-numbered userspace-dependent values; ioctl(TIOCSSERIAL) can
assign the port iotype (which is expected to match the selected
i/o accessors), so iotype values must not be changed.

Cc: Kevin Cernekee <cernekee@gmail.com>
Cc: <stable@vger.kernel.org> # 3.19+
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Reviewed-by: Kevin Cernekee <cernekee@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-03-07 03:39:55 +01:00
Peter Hurley
391f93f2ec serial: core: Rework hw-assisted flow control support
hw-assisted flow control support was added to the serial core
in v3.8 with commits,
dba05832cb ("SERIAL: core: add hardware assisted h/w flow control support")
2cbacafd7a ("SERIAL: core: add hardware assisted s/w flow control support")
9aba8d5b01 ("SERIAL: core: add throttle/unthrottle callbacks for hardware
                assisted flow control")
Since then, additional requirements for serial core support have arisen.
Specifically,
1. Separate tx and rx flow control settings for UARTs which only support
   tx flow control (ie., autoCTS).
2. Disable sw-assisted CTS flow control in autoCTS mode
3. Support for RTS flow control by serial core and userspace in autoRTS mode

Distinguish mode from capability; introduce UPSTAT_AUTORTS, UPSTAT_AUTOCTS
and UPSTAT_AUTOXOFF which, when set by the uart driver, enable serial core
support for hw-assisted rx, hw-assisted tx and hw-assisted in-band/IXOFF
rx flow control, respectively. [Note: hw-assisted in-band/IXON tx flow
control does not require serial core support/intervention and can be
enabled by the uart driver when required.]

These modes must be set/reset in the driver's set_termios() method, based
on termios settings, and thus can be safely queried in any context in which
one of the port lock, port mutex or termios rwsem are held. Set these modes
in the 2 in-tree drivers, omap-serial and 8250_omap, which currently
use UPF_HARD_FLOW/UPF_SOFT_FLOW support.

Retain UPF_HARD_FLOW and UPF_SOFT_FLOW as capabilities; re-define
UPF_HARD_FLOW as both UPF_AUTO_RTS and UPF_AUTO_CTS to allow for distinct
and separate rx and tx flow control capabilities.

Disable sw-assisted CTS flow control when UPSTAT_AUTOCTS is enabled.

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-02-02 10:11:28 -08:00
Peter Hurley
4bf4ea9dca serial: omap_8250: Fix RTS handling
The OMAP3 UART ignores MCR[1] (ie., UART_MCR_RTS) when in autoRTS
mode (UPF_HARD_FLOW + CRTSCTS). This makes it impossible for either
the serial core or userspace to manually flow control the sender.

Disable autoRTS mode when RTS is lowered and restore the previous
mode when RTS is raised.

Note that the OMAP3 UART provides no mechanism for switching from
autoRTS mode without corrupting incoming data; to access the
necessary register, the line control settings must be set to 8-e-2
and thus any data received during that time will be interpreted with
those settings. This corruption has been observed in practice.

Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-01-09 14:10:46 -08:00
Kevin Cernekee
3ffb1a8193 serial: core: Add big-endian iotype
Since most drivers interpret UPIO_MEM32 to mean "little-endian" and use
readl/writel to access the registers, add a parallel UPIO_MEM32BE to
request the use of big-endian MMIO accessors (ioread32be/iowrite32be).

Signed-off-by: Kevin Cernekee <cernekee@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-25 17:06:40 -08:00
Ricardo Ribalda Delgado
a5f276f10f serial_core: Handle TIOC[GS]RS485 ioctls.
The following drivers: 8250_core, atmel_serial, max310x, mcf, omap-serial
and sci16is7xx implement code to handle RS485 ioctls.

In order to avoid code duplication, we implement a simple ioctl handler
on the serial_core layer.

This handler can be used by all the other drivers instead of duplicating
code.

Until this is the only RS485 ioctl handler, it will try first the
rs485_config callback and if it is not present it will call the driver
specific ioctl.

Reviewed-by: Alan Cox <alan@linux.intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-06 14:58:53 -08:00
Peter Hurley
732a84a037 serial: core: Pass termios to set_ldisc() notifications
UART drivers which enable modem status interrupts when switching
to N_PPS line discipline need to determine if modem status
interrupts should be disabled when switching from N_PPS.
Specifically, the set_ldisc() notification needs to evaluate
UART_ENABLE_MS() which requires termios->c_cflag.

Convert in-tree UART drivers to new interface.

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-06 14:57:27 -08:00
Peter Hurley
904326ecac tty,serial: Unify UPF_* and ASYNC_* flag definitions
The userspace-defined ASYNC_* flags in include/uapi/linux/tty_flags.h
are the authoritative bit definitions for the serial_struct flags,
and thus for any derivative values or fields.

Although the serial core provides the TIOCSSERIAL and TIOCGSERIAL
ioctls to set and retrieve these flags from userspace, it defines these
bits independently, as UPF_* macros.

Define the UPF_* macros which are userspace-modifiable directly from
the ASYNC_* symbolic constants. Add compile-time test to ensure the
bits changeable by TIOCSSERIAL match the defined range in the uapi
header.

Add ASYNCB_MAGIC_MULTIPLIER to the uapi header since this bit is
programmable by userspace.

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-05 18:53:54 -08:00
Peter Hurley
d4260b5169 serial: Fix upstat_t sparse warnings
Commit 299245a145,
serial: core: Privatize modem status enable flags, introduced
the upstat_t type and matching bit definitions. The purpose is to
produce sparse warnings if the wrong bit definitions are used
(by warning of implicit integer conversions).

Fix implicit conversion to integer return type from uart_cts_enabled()
and uart_dcd_enabled().

Fixes the following sparse warnings:
drivers/tty/serial/serial_core.c:63:30: warning: incorrect type in return expression (different base types)
drivers/tty/serial/serial_core.c:63:30:    expected int
drivers/tty/serial/serial_core.c:63:30:    got restricted upstat_t
include/linux/serial_core.h:364:30: warning: incorrect type in return expression (different base types)
include/linux/serial_core.h:364:30:    expected bool
include/linux/serial_core.h:364:30:    got restricted upstat_t
include/linux/serial_core.h:364:30: warning: incorrect type in return expression (different base types)
include/linux/serial_core.h:364:30:    expected bool
include/linux/serial_core.h:364:30:    got restricted upstat_t

Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-05 16:15:43 -08:00
Sebastian Andrzej Siewior
234abab143 tty: serial: 8250_core: allow to set ->throttle / ->unthrottle callbacks
The OMAP UART provides support for HW assisted flow control. What is
missing is the support to throttle / unthrottle callbacks which are used
by the omap-serial driver at the moment.
This patch adds the callbacks. It should be safe to add them since they
are only invoked from the serial_core (uart_throttle()) if the feature
flags are set.

Reviewed-by: Tony Lindgren <tony@atomide.com>
Tested-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-09-26 18:01:56 +02:00
Peter Hurley
d01f4d181c serial: core: Privatize tty->hw_stopped
tty->hw_stopped is not used by the tty core and is thread-unsafe;
hw_stopped is a member of a bitfield whose fields are updated
non-atomically and no lock is suitable for serializing updates.

Replace serial core usage of tty->hw_stopped with uport->hw_stopped.
Use int storage which works around Alpha EV4/5 non-atomic byte storage,
since uart_port uses different locks to protect certain fields within the
structure.

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-09-23 21:19:35 -07:00
Peter Hurley
299245a145 serial: core: Privatize modem status enable flags
The serial core uses the tty port flags, ASYNC_CTS_FLOW and
ASYNC_CD_CHECK, to track whether CTS and DCD changes should be
ignored or handled. However, the tty port flags are not safe for
atomic bit operations and no lock provides serialized updates.

Introduce the struct uart_port status field to track CTS and DCD
enable states, and serialize access with uart port lock. Substitute
uart_cts_enabled() helper for tty_port_cts_enabled().

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-09-23 21:19:35 -07:00
Sebastian Andrzej Siewior
b99b121b2a tty: serial: 8250_core: allow to overwrite & export serial8250_startup()
The OMAP version of the 8250 can actually use 1:1 serial8250_startup().
However it needs to be extended by a wake up irq which should to be
requested & enabled at ->startup() time and disabled at ->shutdown() time.

v2…v3: properly copy callbacks
v1…v2: add shutdown callback

Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-09-08 16:32:36 -07:00
Peter Hurley
8a949b07e4 serial: core: Document lock requirement for UPF_* flags updates
The flags field of struct uart_port can only be safely modified
if the port mutex is held; no other lock prevents concurrent
changes from corrupting the field.

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-09-08 16:23:36 -07:00
Greg Kroah-Hartman
266dcff03e Serial: allow port drivers to have a default attribute group
Some serial drivers (like 8250), want to add sysfs files.  We need to do
so in a race-free way, so allow any port to be able to specify an
attribute group that should be added at device creation time.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Yoshihiro YUNOMAE <yoshihiro.yunomae.ez@hitachi.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-07-17 18:21:21 -07:00
Rob Herring
b0b6abd34c serial: earlycon: add DT support
This adds the infrastructure to generic earlycon for earlycon setup
using DT. The actual setup is not enabled until a following commit to
add the FDT parsing.

Signed-off-by: Rob Herring <robh@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Arnd Bergmann <arnd@arndb.de>
Acked-by: Grant Likely <grant.likely@linaro.org>
2014-05-20 15:19:25 -05:00
Rob Herring
9aac588759 tty/serial: add generic serial earlycon
This introduces generic earlycon infrastructure for serial devices
based on the 8250 earlycon. This allows for supporting earlycon option
with other serial devices. The earlycon output is enabled at the time
early_params are processed.

Only architectures that have fixmap support or have functional ioremap
when early_params are processed are supported. This is the same
restriction that the 8250 driver had.

Signed-off-by: Rob Herring <robh@kernel.org>
Cc: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-04-24 16:32:27 -07:00
Linus Walleij
fa2b5ea09e serial: core: delete .set_wake() callback
This deletes the .set_wake() callback in the struct uart_ops.
Apparently this has been unused since pre-git times. In the
old-2.6-bkcvs it is deleted as part of a changeset removing
the PM_SET_WAKEUP from pm_request_t which is since also deleted
from the kernel.

The apropriate way to set wakeups in the kernel is to have a
code snippet like this in .suspend() or .runtime_suspend()
callbacks:

static int foo_suspend(struct device *dev)
{
	if (device_may_wakeup(dev)) {
		/* Enable wakeups, set internal states */
	}
}

This specific callback is not coming back.

Cc: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Len Brown <len.brown@intel.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Kevin Hilman <khilman@deeprootsystems.com>
Cc: Dmitry Artamonow <mad_soft@inbox.ru>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-16 13:16:19 -07:00
Sourav Poddar
cf0ebee0d0 serial: Move "uart_console" def to core header file.
Move "uart_console" definition to serial core header file, so that it can be
used by serial drivers.
Get rid of the uart_console defintion from mpc52xx_uart driver.

Cc: Santosh Shilimkar <santosh.shilimkar@ti.com>
Cc: Rajendra nayak <rnayak@ti.com>
Reviewed-by: Felipe Balbi <balbi@ti.com>
Reviewed-by: Kevin Hilman <khilman@linaro.org>
Tested-by: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Sourav Poddar <sourav.poddar@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-05-20 11:47:21 -07:00
George Spelvin
593fb1ae45 pps: Move timestamp read into PPS code proper
The PPS (Pulse-Per-Second) line discipline has developed a number of
unhealthy attachments to core tty data and functions, ultimately leading
to its breakage.

The previous patches fixed the crashing.  This one reduces coupling further
by eliminating the timestamp parameter from the dcd_change ldisc method.
This reduces header file linkage and makes the extension more generic,
and the timestamp read is delayed only slightly, from just before the
ldisc->ops->dcd_change method call to just after.

Fix attendant build breakage in
    drivers/tty/n_tty.c
    drivers/tty/tty_buffer.c
    drivers/staging/speakup/selection.c
    drivers/staging/dgrp/dgrp_*.c

Cc: William Hubbs <w.d.hubbs@gmail.com>
Cc: Chris Brannon <chris@the-brannons.com>
Cc: Kirk Reiser <kirk@braille.uwo.ca>
Cc: Samuel Thibault <samuel.thibault@ens-lyon.org>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: George Spelvin <linux@horizon.com>
Acked-by: Rodolfo Giometti <giometti@enneenne.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-02-13 10:13:58 -08:00
John Crispin
c420811f11 serial: ralink: adds support for the serial core found on ralink wisoc
The MIPS based Ralink WiSoC platform has 1 or more 8250 compatible serial cores.
To make them work we require the same quirks that are used by AU1x00.

Signed-off-by: John Crispin <blogic@openwrt.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-30 00:15:34 -05:00
Kevin Cernekee
e759d7c53b tty: Update serial core API documentation
Signed-off-by: Kevin Cernekee <cernekee@gmail.com>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-15 21:57:44 -08:00
Ralf Baechle
a205a56dc2 serial: Remove RM9000 series serial driver.
Now that support for RM9000 and platforms based on it has been removed,
remove the serial driver for it as well.  It's really only been a quirk
for an almost 8250 compatible UART anyway.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

 drivers/tty/serial/8250/8250.c  | 70 +----------------------------------------
 drivers/tty/serial/8250/Kconfig |  9 ------
 include/linux/serial_core.h     |  1 -
 3 files changed, 1 insertion(+), 79 deletions(-)
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-15 21:54:41 -08:00
Linus Walleij
6f538fe31c tty: serial core: decouple pm states from ACPI
The serial core is using power states lifted from ACPI for no
good reason. Remove this reference from the documentation and
alter all users to use an enum specific to the serial core
instead, and define it in <linux/serial_core.h>.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Alan Cox <alan@linux.intel.com>
Reviewed-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-15 21:52:23 -08:00
Russell King
9aba8d5b01 SERIAL: core: add throttle/unthrottle callbacks for hardware assisted flow control
Add two callbacks for hardware assisted flow control; we need to know
when the tty layers want us to stop and restart due to their buffer
levels.

Call a driver specific throttle/unthrottle function if and only if the
driver indicates that it is using an enabled hardware assisted flow
control method, otherwise fall back to the non-hardware assisted
methods.

Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-11-04 11:25:56 +00:00
Russell King
dba05832cb SERIAL: core: add hardware assisted h/w flow control support
Ports which are handling h/w flow control in hardware must not have
their RTS state altered depending on the tty's hardware-stopped state.
Avoid this additional logic when setting the termios state.

Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-11-04 11:25:55 +00:00
Russell King
2cbacafd7a SERIAL: core: add hardware assisted s/w flow control support
Ports which are capable of handling s/w flow control in hardware to
know when the s/w flow control termios settings are changed.  Add a
flag to allow the low level serial drivers to indicate that they
support this, and these changes should be propagated to them.

Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-11-04 11:25:54 +00:00
David Howells
607ca46e97 UAPI: (Scripted) Disintegrate include/linux
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Michael Kerrisk <mtk.manpages@gmail.com>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Dave Jones <davej@redhat.com>
2012-10-13 10:46:48 +01:00
Anton Vorontsov
c7f3e7087a tty/serial/core: Introduce poll_init callback
It was noticed that polling drivers (like KGDB) are not able to use
serial ports if the ports were not previously initialized via console.
I.e.  when booting with console=ttyAMA0 kgdboc=ttyAMA0, everything works
fine, but with console=ttyFOO kgdboc=ttyAMA0, the kgdboc doesn't work.

This is because we don't initialize the hardware. Calling ->startup() is
not an option, because drivers request interrupts there, and drivers
fail to handle situations when tty isn't opened with interrupts enabled.

So, we have to implement a new callback (actually, tty_ops already have
a similar callback), which does everything needed to initialize just the
hardware.

Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-09-26 13:47:02 -07:00
Sean Young
65ecc9c02d 8250: blacklist Winbond CIR port
The legacy serial driver will detect the Winbond CIR device as a serial
port, since it looks exactly like a serial port unless you know what
it is from the PNP ID.

Here we track this port as a special PORT_8250_CIR type, preventing the
legacy serial driver from probing it.

Signed-off-by: Sean Young <sean@mess.org>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-09-26 13:25:41 -07:00
Alexander Shiyan
f65444187a serial: New serial driver MAX310X
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: Alexander Shiyan <shc_work@mail.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-08-16 12:12:25 -07:00
Roland Stigge
7a5145965c serial/8250: Add LPC3220 standard UART type
LPC32xx has "Standard" UARTs that are actually 16550A compatible but have
bigger FIFOs. Since the already supported 16X50 line still doesn't match here,
we agreed on adding a new type.

Signed-off-by: Roland Stigge <stigge@antcom.de>
Acked-by: Alan Cox <alan@linux.intel.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-06-12 15:45:56 -07:00
Greg Kroah-Hartman
665ab0f3c8 Merge 3.4-rc3 into tty-next
This allows us to pick up some changes needed for other serial patches.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-04-18 15:57:31 -07:00
Dan Williams
bf03f65b79 tegra, serial8250: add ->handle_break() uart_port op
The "KT" serial port has another use case for a "received break" quirk,
so before adding another special case to the 8250 core take this
opportunity to push such quirks out of the core and into a uart_port op.

Stephen says:
"If the callback function is to no longer live in 8250.c itself,
 arch/arm/mach-tegra/devices.c isn't logically a good place to put it,
 and that file will be going away once we get rid of all the board files
 and move solely to device tree."

...so since 8250_pci.c houses all the quirks for pci serial devices this
quirk is similarly housed in of_serial.c.  Once the open firmware
conversion completes the infrastructure details
(include/linux/of_serial.h, and the export) can all be removed to make
this self contained to of_serial.c.

Cc: Nhan H Mai <nhan.h.mai@intel.com>
Cc: Colin Cross <ccross@android.com>
Cc: Olof Johansson <olof@lixom.net>
[stephen: kill CONFIG_SERIAL_TEGRA in favor just using CONFIG_ARCH_TEGRA]
Cc: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Sudhakar Mamillapalli <sudhakar@fb.com>
Reported-by: Alan Cox <alan@lxorguk.ukuu.org.uk>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: Stephen Warren <swarren@wwwdotorg.org>
Tested-by: Stephen Warren <swarren@wwwdotorg.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-04-18 15:07:53 -07:00
Dan Williams
bc02d15a34 serial/8250_pci: add a "force background timer" flag and use it for the "kt" serial port
Workaround dropped notifications in the iir register.  Register reads
coincident with new interrupt notifications sometimes result in this
device clearing the interrupt event without reporting it in the read
data.

The serial core already has a heuristic for determining when a device
has an untrustworthy iir register.  In this case when we apriori know
that the iir is faulty use a flag (UPF_BUG_THRE) to bypass the test and
force usage of the background timer.

[stable: 3.3.x]
Acked-by: Alan Cox <alan@linux.intel.com>
Cc: stable <stable@vger.kernel.org>
Reported-by: Nhan H Mai <nhan.h.mai@intel.com>
Reported-by: Sudhakar Mamillapalli <sudhakar@fb.com>
Tested-by: Nhan H Mai <nhan.h.mai@intel.com>
Tested-by: Sudhakar Mamillapalli <sudhakar@fb.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-04-09 10:38:30 -07:00
Dan Williams
49b532f96f Revert "serial/8250_pci: setup-quirk workaround for the kt serial controller"
This reverts commit 448ac154c9.

The semantic of UPF_IIR_ONCE is only guaranteed to workaround the race
condition in the kt serial's iir register if the only source of
interrupts is THRE (fifo-empty) events.  An modem status event at the
wrong time can again cause an iir read to drop the 'empty' status
leading to a hang.  So, revert this in preparation for using the
existing "I don't trust my iir register" workaround in the 8250 core
(UART_BUG_THRE).

[stable: 3.3.x]
Cc: stable <stable@vger.kernel.org>
Acked-by: Alan Cox <alan@linux.intel.com>
Cc: Sudhakar Mamillapalli <sudhakar@fb.com>
Reported-by: Nhan H Mai <nhan.h.mai@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-04-09 10:34:52 -07:00
Paul Gortmaker
927353a756 serial: introduce generic port in/out helpers
Looking at the existing serial drivers (esp. the 8250 derived
variants) we see a common trend.  They create a hardware specific
port struct, which in turn contains a generic serial_port struct.

The other trend, is that they all create some sort of shortcut
to go through the hardware specific struct, to the serial_port
struct, which has the basic in/out operations within.  Looking
for the serial_in and serial_out in several drivers shows this.

Rather than let this continue, lets create a generic set of
similar helper wrappers that can be used on a struct port, so
we can eliminate bouncing out through hardware specific struct
pointers just to come back into struct port where possible.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-03-09 12:47:56 -08:00
Uwe Kleine-König
3afbd89c96 serial/efm32: add new driver
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2012-01-26 11:29:47 -08:00
Linus Torvalds
4964e0664c Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus
* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus: (119 commits)
  MIPS: Delete unused function add_temporary_entry.
  MIPS: Set default pci cache line size.
  MIPS: Flush huge TLB
  MIPS: Octeon: Remove SYS_SUPPORTS_HIGHMEM.
  MIPS: Octeon: Add support for OCTEON II PCIe
  MIPS: Octeon: Update PCI Latency timer and enable more error reporting.
  MIPS: Alchemy: Update cpu-feature-overrides
  MIPS: Alchemy: db1200: Improve PB1200 detection.
  MIPS: Alchemy: merge Au1000 and Au1300-style IRQ controller code.
  MIPS: Alchemy: chain IRQ controllers to MIPS IRQ controller
  MIPS: Alchemy: irq: register pm at irq init time
  MIPS: Alchemy: Touchscreen support on DB1100
  MIPS: Alchemy: Hook up IrDA on DB1000/DB1100
  net/irda: convert au1k_ir to platform driver.
  MIPS: Alchemy: remove unused board headers
  MTD: nand: make au1550nd.c a platform_driver
  MIPS: Netlogic: Mark Netlogic chips as SMT capable
  MIPS: Netlogic: Add support for XLP 3XX cores
  MIPS: Netlogic: Merge some of XLR/XLP wakup code
  MIPS: Netlogic: Add default XLP config.
  ...

Fix up trivial conflicts in arch/mips/kernel/{perf_event_mipsxx.c,
traps.c} and drivers/tty/serial/Makefile
2012-01-14 13:05:21 -08:00
Gabor Juhos
d57f341ba0 SERIAL: AR933X: Add driver for the built-in UART of the SoC
This patch adds the driver for the built-in UART of the
Atheros AR933X SoCs.

Signed-off-by: Gabor Juhos <juhosg@openwrt.org>
Cc: linux-mips@linux-mips.org
Cc: Kathy Giori <kgiori@qca.qualcomm.com>
Cc: "Luis R.  Rodriguez" <rodrigue@qca.qualcomm.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: linux-serial@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/2526/
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2011-12-07 22:02:46 +00:00
Dan Williams
448ac154c9 serial/8250_pci: setup-quirk workaround for the kt serial controller
Workaround dropped notifications in the iir register.  Prevent reads
coincident with new interrupt notifications by reading the iir at most
once per interrupt.

Reported-by: Nhan H Mai <nhan.h.mai@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-11-26 20:11:20 -08:00
Jiri Slaby
027d7dacf7 TTY: serial, cleanup include file
There are some functions (uart_handle_dcd_change, _handle_cts_change,
_insert_char) which are big enough to not be inlined. So move them
from .h to .c. We need to export them so that modules can actually use
them.

They will be even bigger when we introduce tty refcounting to them.

While at it, cleanup the "Proud member of Uglyhacks'R'US". It means,
define uart_handle_sysrq_char only when SUPPORT_SYSRQ is set.
Otherwise define it as a macro. This is needed for some arm driver
where the second parameter is undefined if expanded.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-11-15 15:58:56 -08:00
Søren Holm
06315348b1 serial: Support the EFR-register of XR1715x uarts.
The EFR (Enhenced-Features-Register) is located at a different offset
than the other devices supporting UART_CAP_EFR. This change add a special
setup quick to set UPF_EXAR_EFR on the port. UPF_EXAR_EFR is then used to
the port type to PORT_XR17D15X since it is for sure a XR17D15X uart.

Signed-off-by: Søren Holm <sgh@sgh.dk>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-09-22 15:50:38 -07:00
Jamie Iles
4834d02897 tty: serial8250: remove UPIO_DWAPB{,32}
Now that platforms can override the port IRQ handler and the only user
of these UPIO modes has been converted over, kill off UPIO_DWAPB and
UPIO_DWAPB32.

Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Jamie Iles <jamie@jamieiles.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-08-23 10:53:00 -07:00
Jamie Iles
a74036f512 tty: serial: allow ports to override the irq handler
Some serial ports may have unusal requirements for interrupt handling
(e.g. the Synopsys DesignWare 8250-alike port and it's busy detect
interrupt).  Add a .handle_irq callback that can be used for platforms
to override the interrupt behaviour in a similar fashion to the
.serial_out and .serial_in callbacks.

Signed-off-by: Jamie Iles <jamie@jamieiles.com>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-08-23 10:52:58 -07:00
Jiri Slaby
6a3e492b6d TTY: serial, remove tasklet for tty_wakeup
tty_wakeup can be called from any context. So there is no need to have
an extra tasklet for calling that. Hence save some space and remove
the tasklet completely.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-08-23 10:34:06 -07:00
Stephen Warren
4539c24fe4 tty/serial: Add explicit PORT_TEGRA type
Tegra's UART is currently auto-detected as PORT_XSCALE due to register
bit UART_IER.UUE being writable. However, the Tegra documentation states
that this register bit is reserved. Hence, we should not program it.

Instead, the documentation specifies that the UART is 16550 compatible.
However, Tegra does need register bit UART_IER.RTOIE set, which is not
enabled by any 16550 port type. This was not noticed before, since
PORT_XSCALE enables CAP_UUE, which conflates both UUE and RTOIE bit
programming.

This change defines PORT_TEGRA that doesn't set UART_CAP_UUE, but does
set UART_CAP_RTOIE, which is a new capability indicating that the RTOIE
bit needs to be enabled.

Based-on-code-by: Laxman Dewangan <ldewangan@nvidia.com>
Cc: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-05-19 16:51:01 -07:00
John Linn
61ec901698 tty/serial: add support for Xilinx PS UART
The Xilinx PS Uart is used on the new ARM based SoC. This
UART is not compatible with others such that a seperate
driver is required.

Signed-off-by: John Linn <john.linn@xilinx.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-05-03 10:26:39 -07:00
Alexander Gordeev
6f4229b511 pps: unify timestamp gathering
Add a helper function to gather timestamps.  This way clients don't have
to duplicate it.

Signed-off-by: Alexander Gordeev <lasaine@lvk.cs.msu.su>
Acked-by: Rodolfo Giometti <giometti@linux.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 08:03:19 -08:00
Govindraj.R
3f960dbb9d Serial: Avoid unbalanced IRQ wake disable during resume
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: Govindraj.R <govindraj.raja@ti.com>
Reported-by: Paul Walmsley <paul@pwsan.com>
Cc: Santosh Shilimkar <santosh.shilimkar@ti.com>
Acked-by: Kevin Hilman <khilman@deeprootsystems.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-12-16 13:14:32 -08:00
Jamie Iles
a3ae0fc34f 8250: add a UPIO_DWAPB32 for 32 bit accesses
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: Jamie Iles <jamie@jamieiles.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-12-10 15:19:38 -08:00