Commit Graph

78 Commits

Author SHA1 Message Date
Andrew Jackson 98267d33e2 serial: pl011: Add device tree support for RX DMA polling
Add equivalent attributes to those provided in the platform data
for use when RX DMA is enabled.

Signed-off-by: Andrew Jackson <Andrew.Jackson@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-07 08:35:56 -08:00
Andrew Jackson 2d3b7d6e7d serial: pl011: Don't enable RX DMA if residue processing not supported
If the DMA engine doesn't support residue processing then the RX DMA
handling won't work terribly well if polling is enabled.  So, disable
RX DMA if residue handling isn't available.

Signed-off-by: Andrew Jackson <Andrew.Jackson@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-07 08:35:56 -08:00
Andrew Jackson c64be9231e serial: pl011: Set length of DMA transfer
The DMA engines on some systems require that the dma_length is set
when using scatter gather lists.

Signed-off-by: Andrew Jackson <Andrew.Jackson@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-07 08:35:55 -08:00
Andrew Jackson e2a545a6ae serial: pl011: Avoid assumptions about buffer size when refilling TX DMA
The existing code assumed that PL011_DMA_BUFFER_SIZE == UART_XMIT_SIZE,
which may not always be the case.  This allows for these two being
different sizes and not copying too much data.

Signed-off-by: Andrew Jackson <Andrew.Jackson@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-07 08:35:55 -08:00
Andrew Jackson 4c0be45b18 serial: pl011: Allocate TX DMA buffer from DMA capable memory
Allocating with __GFP_DMA avoids the need for bounce buffers

Signed-off-by: Andrew Jackson <Andrew.Jackson@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-07 08:35:55 -08:00
Peter Hurley 36f339d136 serial: pl011: Fix build breakage with !CONFIG_DMA_ENGINE
Commit 479e9b94fd ("serial: Refactor uart_flush_buffer() from
uart_close") refactored the uart_flush_buffer() in uart_close() into
those drivers that define a flush_buffer() method. However, in the
amba-pl011 driver configured without CONFIG_DMA_ENGINE, flush_buffer()
is a NULL method, so the direct call fails to compile.

Check and call the flush_buffer() method through the ops table instead.

Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Cc: Russell King <linux@arm.linux.org.uk>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-06 09:35:54 -08:00
Peter Hurley 479e9b94fd serial: Refactor uart_flush_buffer() from uart_close()
In the context of the final tty & port close, flushing the tx
ring buffer after the hardware has already been shutdown and
the ring buffer freed is neither required nor desirable.

uart_flush_buffer() performs 3 operations:
1. Resets tx ring buffer indices, but the tx ring buffer has
   already been freed and the indices are reset if the port is
   re-opened.
2. Calls uart driver's flush_buffer() method
   5 in-tree uart drivers define flush_buffer() methods:
     amba-pl011, atmel-serial, imx, serial-tegra, timbuart
   These have been refactored into the shutdown() method, if
   required.
3. Kicks the ldisc for more writing, but this is undesirable.
   The file handle is being released; any waiting writer will
   will be kicked out by tty_release() with a warning. Further,
   the N_TTY ldisc may generate SIGIO for a file handle which
   is no longer valid.

Cc: Nicolas Ferre <nicolas.ferre@atmel.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Laxman Dewangan <ldewangan@nvidia.com>
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
Daniel Thompson a5820c24a8 serial: amba-pl011: Use container_of() to get uart_amba_port
Universally adopt container_of() for all pointer conversion from
uart_port to uart_amba_port.

Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Cc: Peter Hurley <peter@hurleysoftware.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: linux-serial@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-09-08 16:26:07 -07:00
Tushar Behera 7f6d942a81 serial: amba-pl011: Remove redundant label
The label 'out' is only used to return the error code. We can return the
error code directly and remove 'out' label.

Signed-off-by: Tushar Behera <tushar.b@samsung.com>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-07-09 17:13:54 -07:00
Peter Hurley ef8b9ddcb4 serial: Fix IGNBRK handling
If IGNBRK is set without either BRKINT or PARMRK set, some uart
drivers send a 0x00 byte for BREAK without the TTYBREAK flag to the
line discipline, when it should send either nothing or the TTYBREAK flag
set. This happens because the read_status_mask masks out the BI
condition, which uart_insert_char() then interprets as a normal 0x00 byte.

SUS v3 is clear regarding the meaning of IGNBRK; Section 11.2.2, General
Terminal Interface - Input Modes, states:
  "If IGNBRK is set, a break condition detected on input shall be ignored;
   that is, not put on the input queue and therefore not read by any
   process."

Fix read_status_mask to include the BI bit if IGNBRK is set; the
lsr status retains the BI bit if a BREAK is recv'd, which is
subsequently ignored in uart_insert_char() when masked with the
ignore_status_mask.

Affected drivers:
8250 - all
serial_txx9
mfd
amba-pl010
amba-pl011
atmel_serial
bfin_uart
dz
ip22zilog
max310x
mxs-auart
netx-serial
pnx8xxx_uart
pxa
sb1250-duart
sccnxp
serial_ks8695
sirfsoc_uart
st-asc
vr41xx_siu
zs
sunzilog
fsl_lpuart
sunsab
ucc_uart
bcm63xx_uart
sunsu
efm32-uart
pmac_zilog
mpsc
msm_serial
m32r_sio

Unaffected drivers:
omap-serial
rp2
sa1100
imx
icom

Annotated for fixes:
altera_uart
mcf

Drivers without break detection:
21285
xilinx-uartps
altera_jtaguart
apbuart
arc-uart
clps711x
max3100
uartlite
msm_serial_hs
nwpserial
lantiq
vt8500_serial

Unknown:
samsung
mpc52xx_uart
bfin_sport_uart
cpm_uart/core

Fixes: Bugzilla #71651, '8250_core.c incorrectly handles IGNBRK flag'
Reported-by: Ivan <athlon_@mail.ru>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-06-19 13:04:52 -07:00
Rob Herring 45e0f0f568 tty/serial: pl011: add DT based earlycon support
Enable DT based earlycon initialization for the pl011 uart.

Signed-off-by: Rob Herring <robh@kernel.org>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.cz>
Acked-by: Grant Likely <grant.likely@linaro.org>
2014-05-20 15:19:26 -05:00
Rob Herring 0d3c673e78 tty/serial: pl011: add generic earlycon support
Add earlycon support for the pl011 serial port. This allows enabling
the pl011 for console when early_params are processed. This is based
on the arm64 earlyprintk support and is intended to replace it.

Signed-off-by: Rob Herring <robh@kernel.org>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-04-24 16:32:27 -07:00
Guennadi Liakhovetski 1e7da05304 serial: amba-pl011: fix regression, causing an Oops on rmmod
A recent commit ef2889f7ff "serial: pl011:
Move uart_register_driver call to device probe" introduced a regression,
causing the pl011 driver to Oops if more than 1 port have been probed. Fix
the Oops by only calling uart_unregister_driver() once after the last port
has been removed.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-04-16 14:31:13 -07:00
Guennadi Liakhovetski b2aeb775f8 serial: pl011: change Rx burst size to half of trigger level
The amba-pl011.c driver sets DMA burst size equal to FIFO trigger level.
If now exactly DMA burst size bytes are received, the DMAC will retrieve
them all and no Rx timeout interrupt will be generated. To fix that set
the burst size to half the FIFO trigger level.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-04-16 14:17:44 -07:00
Tushar Behera ef2889f7ff serial: pl011: Move uart_register_driver call to device probe
uart_register_driver call binds the driver to a specific device
node through tty_register_driver call. This should typically happen
during device probe call.

In a multiplatform scenario, it is possible that multiple serial
drivers are part of the kernel. Currently the driver registration fails
if multiple serial drivers with same default major/minor numbers are
included in the kernel.

A typical case is observed with amba-pl011 and samsung-uart drivers.

Signed-off-by: Tushar Behera <tushar.behera@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-02-13 10:33:00 -08:00
Guennadi Liakhovetski c25a1ad707 serial: pl011: fix fall back from DMA to interrupt mode
When falling back from DMA to interrupt mode the receive interrupt has to
be re-enabled to catch new incoming data.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-12-17 09:36:23 -08:00
Guennadi Liakhovetski 30ae585918 serial: pl011: (cosmetic) remove superfluous register write
In pl011_rx_chars() if pl011_dma_rx_trigger_dma() succeeds it will disable
the receive interrupt, no need to do this again.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-12-17 09:36:23 -08:00
Jon Medhurst 570d291048 serial: amba-pl011: preseserve hardware settings during initialisation
During initialisation, a UART may already be in use for a console, so
take care to preserve things like baud rate and data format to avoid
corrupting console output.

Signed-off-by: Jon Medhurst <tixy@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-12-17 09:35:38 -08:00
Jon Medhurst b60f2f66a5 serial: amba-pl011: factor out code for writing LCR_H register
The code to cope with a split tx/rx LCR_H register is non-trivial
so put it into it's own function to avoid duplication.

Signed-off-by: Jon Medhurst <tixy@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-12-17 09:35:37 -08:00
Jon Medhurst fe43390702 serial: amba-pl011: use port lock to guard control register access
When the pl011 is being used for a console, pl011_console_write forces
the control register (CR) to enable the UART for transmission and then
restores this to the original value afterwards. It does this while
holding the port lock.

Unfortunately, when the uart is started or shutdown - say in response to
userland using the serial device for a terminal - then this updates the
control register without any locking.

This means we can have

  pl011_console_write   Save CR
  pl011_startup         Initialise CR, e.g. enable receive
  pl011_console_write   Restore old CR with receive not enabled

this result is a serial port which doesn't respond to any input.

A similar race in reverse could happen when the device is shutdown.

We can fix these problems by taking the port lock when updating CR.

Signed-off-by: Jon Medhurst <tixy@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-12-17 09:35:37 -08:00
Greg Kroah-Hartman 8f898bfd04 Revert "serial: pl011: use DMA RX polling by default"
This reverts commit 17438217a6 on request
of Linus Walleij:
	Greg can you please drop or revert
	commit 17438217a6
	"serial: pl011: use DMA RX polling by default"
	from the TTY tree until this has been sorted out?

Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-12-17 09:33:18 -08:00
Linus Walleij 17438217a6 serial: pl011: use DMA RX polling by default
Making DMA RX polling optional when DMA is on was just
over-cautious: there is one single system in the kernel tree
using this facility, Ux500 and after some testing I turned
this on also for Ux500, which means it should simply be on
by default if DMA is enabled.

Cc: Jongsung Kim <neidhard.kim@lge.com>
Cc: Chanho Min <chanho.min@lge.com>
Cc: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-12-08 17:09:07 -08:00
Ulf Hansson d0ce850d60 serial: pl011: Convert to modern PM ops
Convert to modern PM ops and use the SIMPLE_DEV_PM_OPS macro to set up
the PM callbacks.

Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-12-08 17:09:06 -08:00
Baruch Siach 187094feeb serial: pl011: remove redundant early amba_ports declaration
This early amba_ports declaration was introduced by commit c16d51a32 (amba
pl011: workaround for uart registers lockup) for use in the pl011_lockup_wa()
routine. This routine was later removed by commit 4fd0690bb (serial: pl011:
implement workaround for CTS clear event issue).

Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-12-08 16:44:21 -08:00
Michal Simek 7ea816a0c3 serial: Remove unnecessary amba_set_drvdata()
Driver core clears the driver data to NULL after device_release
or on probe failure, so just remove it from here.

Driver core change:
"device-core: Ensure drvdata = NULL when no driver is bound"
(sha1: 0998d06310)

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-03 16:09:47 -07:00
Fabio Estevam b83286bfa8 serial: amba-pl011: Use __releases/__acquires annotations
Fix the following sparse warnings:

drivers/tty/serial/amba-pl011.c:687:20: warning: context imbalance in 'pl011_dma_flush_buffer' - unexpected unlock
drivers/tty/serial/amba-pl011.c:1200:13: warning: context imbalance in 'pl011_rx_chars' - unexpected unlock

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-08-12 11:37:48 -07:00
Jingoo Han 574de559c1 serial: use dev_get_platdata()
Use the wrapper function for retrieving the platform data instead of
accessing dev->platform_data directly.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-07-31 17:56:15 -07:00
Linus Torvalds 3dbde57ad9 Pin control changes for the v3.11 kernel cycle:
- A large slew of improvements of the Genric pin configuration
   support, and deployment in four different platforms:
   Rockchip, Super-H PFC, ABx500 and TZ1090. Support BIAS_BUS_HOLD,
   get device tree parsing and debugfs support into shape.
 
 - We also have device tree support with generic naming conventions
   for the generic pin configuration.
 
 - Delete the unused and confusing direct pinconf API. Now state
   transitions is *the* way to control pins and multiplexing.
 
 - New drivers for Rockchip, TZ1090, and TZ1090 PDC.
 
 - Two pin control states related to power management are now
   handled in the device core: "sleep" and "idle", removing a lot
   of boilerplate code in drivers. We do not yet know if this is
   the final word for pin PM, but it already make things a lot
   easier to handle.
 
 - Handle sparse GPIO ranges passing a list of disparate pins, and
   utilize these in the new BayTrail (x86 Atom SoC) driver.
 
 - Make the sunxi (AllWinner) driver handle external interrupts.
 
 - Make it possible for pinctrl-single to handle the case where
   several pins are managed by a single register, and augment it to
   handle sleep modes.
 
 - Cleanups and improvements for the abx500 drivers.
 
 - Move Sirf pin control drivers to their own directory, support
   save/restore of context and add support for the SiRFatlas6 SoC.
 
 - PMU muxing for the Dove pinctrl driver.
 
 - Finalization and support for VF610 in the i.MX6 pinctrl driver.
 
 - Smoothen out various Exynos rough edges.
 
 - Generic cleanups of various kinds.
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Merge tag 'pinctrl-for-v3.11-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl

Pull pin control changes from Linus Walleij:

 - A large slew of improvements of the Genric pin configuration support,
   and deployment in four different platforms: Rockchip, Super-H PFC,
   ABx500 and TZ1090.  Support BIAS_BUS_HOLD, get device tree parsing
   and debugfs support into shape.

 - We also have device tree support with generic naming conventions for
   the generic pin configuration.

 - Delete the unused and confusing direct pinconf API.  Now state
   transitions is *the* way to control pins and multiplexing.

 - New drivers for Rockchip, TZ1090, and TZ1090 PDC.

 - Two pin control states related to power management are now handled in
   the device core: "sleep" and "idle", removing a lot of boilerplate
   code in drivers.  We do not yet know if this is the final word for
   pin PM, but it already make things a lot easier to handle.

 - Handle sparse GPIO ranges passing a list of disparate pins, and
   utilize these in the new BayTrail (x86 Atom SoC) driver.

 - Make the sunxi (AllWinner) driver handle external interrupts.

 - Make it possible for pinctrl-single to handle the case where several
   pins are managed by a single register, and augment it to handle sleep
   modes.

 - Cleanups and improvements for the abx500 drivers.

 - Move Sirf pin control drivers to their own directory, support
   save/restore of context and add support for the SiRFatlas6 SoC.

 - PMU muxing for the Dove pinctrl driver.

 - Finalization and support for VF610 in the i.MX6 pinctrl driver.

 - Smoothen out various Exynos rough edges.

 - Generic cleanups of various kinds.

* tag 'pinctrl-for-v3.11-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl: (82 commits)
  pinctrl: vt8500: wmt: remove redundant dev_err call in wmt_pinctrl_probe()
  pinctrl: remove bindings for pinconf options needing more thought
  pinctrl: remove slew-rate parameter from tz1090
  pinctrl: set unit for debounce time pinconfig to usec
  pinctrl: more clarifications for generic pull configs
  pinctrl: rip out the direct pinconf API
  pinctrl-tz1090-pdc: add TZ1090 PDC pinctrl driver
  pinctrl-tz1090: add TZ1090 pinctrl driver
  pinctrl: samsung: Staticize drvdata_list
  pinctrl: rockchip: Add missing irq_gc_unlock() call before return error
  pinctrl: abx500: rework error path
  pinctrl: abx500: suppress hardcoded value
  pinctrl: abx500: factorize code
  pinctrl: abx500: fix abx500_gpio_get()
  pinctrl: abx500: fix abx500_pin_config_set()
  pinctrl: abx500: Add device tree support
  sh-pfc: Guard DT parsing with #ifdef CONFIG_OF
  pinctrl: add Intel BayTrail GPIO/pinctrl support
  pinctrl: fix pinconf_ops::pin_config_dbg_parse_modify kerneldoc
  pinctrl: Staticize local symbols
  ...

Conflicts:
	drivers/net/ethernet/ti/davinci_mdio.c
	drivers/pinctrl/Makefile
2013-07-03 11:48:03 -07:00
Linus Walleij 2b996fc500 tty: serial: modify PL011 driver to use pinctrl PM helpers
This augments the PL011 UART driver to utilize the new pinctrl
core PM helpers to transition the driver to default and sleep
states, cutting away some boilerplate code.

Cc: Hebbar Gururaja <gururaja.hebbar@ti.com>
Cc: Mark Brown <broonie@kernel.org>
Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: Kevin Hilman <khilman@linaro.org>
Cc: Stephen Warren <swarren@wwwdotorg.org>
Acked-by: Wolfram Sang <wsa@the-dreams.de>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2013-06-16 11:56:52 +02:00
Greg Kroah-Hartman 8095e4e81b Merge 3.10-rc3 into tty-next
We want these fixes.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-05-27 10:57:53 +09:00
Lee Jones f6b6f52b58 serial: pl011: protect attribute read from NULL platform data struct
It's completely feasible that platform data will be empty i.e. when
booting with Device Tree with no device AUXDATA. So we must protect
it's use in these use-cases, or risk a kernel Oops.

Cc: Russell King <linux@arm.linux.org.uk>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-05-20 11:54:55 -07:00
Jongsung Kim ea33640a93 tty: serial: amba-pl011: revise to use amba_rev macro
This patch replaces the ugly bit-operations with the convenient
amba_rev macro from the get_fifosize_arm function. The type of
get_fifosize member function is also slightly changed to take
a pointer to the amba_device.

Signed-off-by: Jongsung Kim <neidhard.kim@lge.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-05-20 11:53:46 -07:00
Linus Torvalds 1bf25e78af ARM: arm-soc: late cleanups
These are cleanups and smaller changes that either depend on earlier
 feature branches or came in late during the development cycle.
 We normally try to get all cleanups early, so these are the exceptions:
 
 - A follow-up on the clocksource reworks, hopefully the last time
   we need to merge clocksource subsystem changes through arm-soc.
   A first set of patches was part of the original 3.10 arm-soc cleanup
   series because of interdependencies with timer drivers now moved out
   of arch/arm.
 
 - Migrating the SPEAr13xx platform away from using auxdata for DMA
   channel descriptions towards using information in device tree,
   based on the earlier SPEAr multiplatform series
 
 - A few follow-ups on the Atmel SAMA5 support and other changes
   for Atmel at91 based on the larger at91 reworks.
 
 - Moving the armada irqchip implementation to drivers/irqchip
 
 - Several OMAP cleanups following up on the larger series already
   merged in 3.10.
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Merge tag 'cleanup-for-linus-2' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc

Pull ARM SoC late cleanups from Arnd Bergmann:
 "These are cleanups and smaller changes that either depend on earlier
  feature branches or came in late during the development cycle.  We
  normally try to get all cleanups early, so these are the exceptions:

   - A follow-up on the clocksource reworks, hopefully the last time we
     need to merge clocksource subsystem changes through arm-soc.

     A first set of patches was part of the original 3.10 arm-soc
     cleanup series because of interdependencies with timer drivers now
     moved out of arch/arm.

   - Migrating the SPEAr13xx platform away from using auxdata for DMA
     channel descriptions towards using information in device tree,
     based on the earlier SPEAr multiplatform series

   - A few follow-ups on the Atmel SAMA5 support and other changes for
     Atmel at91 based on the larger at91 reworks.

   - Moving the armada irqchip implementation to drivers/irqchip

   - Several OMAP cleanups following up on the larger series already
     merged in 3.10."

* tag 'cleanup-for-linus-2' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (50 commits)
  ARM: OMAP4: change the device names in usb_bind_phy
  ARM: OMAP2+: Fix mismerge for timer.c between ff931c82 and da4a686a
  ARM: SPEAr: conditionalize SMP code
  ARM: arch_timer: Silence debug preempt warnings
  ARM: OMAP: remove unused variable
  serial: amba-pl011: fix !CONFIG_DMA_ENGINE case
  ata: arasan: remove the need for platform_data
  ARM: at91/sama5d34ek.dts: remove not needed compatibility string
  ARM: at91: dts: add MCI DMA support
  ARM: at91: dts: add i2c dma support
  ARM: at91: dts: set #dma-cells to the correct value
  ARM: at91: suspend both memory controllers on at91sam9263
  irqchip: armada-370-xp: slightly cleanup irq controller driver
  irqchip: armada-370-xp: move IRQ handler to avoid forward declaration
  irqchip: move IRQ driver for Armada 370/XP
  ARM: mvebu: move L2 cache initialization in init_early()
  devtree: add binding documentation for sp804
  ARM: integrator-cp: convert use CLKSRC_OF for timer init
  ARM: versatile: use OF init for sp804 timer
  ARM: versatile: add versatile dtbs to dtbs target
  ...
2013-05-07 11:22:14 -07:00
Arnd Bergmann aabdd2901a serial: amba-pl011: fix !CONFIG_DMA_ENGINE case
I changed the prototype of the function earlier but only
in the section for CONFIG_DMA_ENGINE, not the alternative.
This makes the driver build again, e.g. for vexpress_defconfig.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2013-04-20 09:40:33 +02:00
Jongsung Kim 78506f223a ARM: PL011: add support for extended FIFO-size of PL011-r1p5
The latest r1p5-revision of the ARM PL011 UART has 32-byte FIFOs,
while all earlier ones have 16-byte FIFOs. This patch suggests
a way to set the FIFO-size correctly & flexibly by using a member
function named get_fifosize, rather than using the fifosize member
variable. The function takes the UARTPeriphID, and returns the
correct FIFO size.

Signed-off-by: Jongsung Kim <neidhard.kim@lge.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-17 10:15:21 -07:00
Chanho Min 89fa28dbe0 amba-pl011: fix build error if CONFIG_DMA_ENGINE is not enabled
Following patch will fix build error if CONFIG_DMA_ENGINE is unset.

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Chanho Min <chanho.min@lge.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-03 11:34:55 -07:00
Chanho Min cb06ff102e ARM: PL011: Add support for Rx DMA buffer polling.
In DMA support, The received data is not pushed to tty until the DMA buffer
is filled. But some megabyte rate chips such as BT expect fast response and
data should be pushed immediately. In order to fix this issue, We suggest
the use of the timer for polling DMA buffer.
In our test, no data loss occurred at high-baudrate as compared with interrupt-
driven (We tested with 3Mbps).
We changes:

- We add timer for polling. If we set poll_timer to 10, every 10ms,
 timer handler checks the residue in the dma buffer and transfer data
 to the tty. Also, last_residue is updated for the next polling.

- poll_timeout is used to prevent the timer's system cost.
  If poll_timeout is set to 3000 and no data is received in 3 seconds,
  we inactivate poll timer and driver falls back to interrupt-driven.
  When data is received again in FIFO and UART irq is occurred, we switch
  back to DMA mode and start polling.

- We use consistent DMA mappings to avoid from the frequent cache operation
  of the timer function for default.

- pl011_dma_rx_chars is modified. the pending size is recalculated because
  data can be taken by polling.

- the polling time is adjusted if dma rx poll is enabled but no rate is
  specified. Ideal polling interval to push 1 character at every interval
  is the reciprocal of 'baud rate / 10 line bits per character / 1000 ms
  per sec'. But It is very aggressive to system. Experimentally,
 '10000000 / baud' is suitable to receive dozens of characters. the poll rate
 can be specified statically by dma_rx_poll_rate of the platform data as well.

Changes compared to v1:
 - Use of consistent DMA mappings.
 - Added dma_rx_poll_rate in platform data to specify the polling interval.
 - Added dma_rx_poll_timeout in platform data to specify the polling timeout.

Changes compared to v2:
 - Use of consistent DMA mappings for default.
 - Added dma_rx_poll_enable in platform data to adjust the polling time
   according to the baud rate.
 - remove unnecessary lock from the polling function.

Signed-off-by: Chanho Min <chanho.min@lge.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-03-29 09:20:05 -07:00
Arnd Bergmann 787b0c1f8e serial: pl011: use generic DMA slave configuration if possible
With the new OF DMA binding, it is possible to completely avoid the
need for platform_data for configuring a DMA channel. In cases where the
platform has already been converted, calling dma_request_slave_channel
should get all the necessary information from the device tree.

This also adds a binding document specific to the pl011 controller,
and extends the generic primecell binding to mention "dmas" and other
common properties.

Like the patch that converts the dw_dma controller, this is completely
untested and is looking for someone to try it out.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Cc: devicetree-discuss@lists.ozlabs.org
Cc: linux-arm-kernel@lists.infradead.org
2013-03-12 17:56:09 +01:00
Jiri Slaby 2e124b4a39 TTY: switch tty_flip_buffer_push
Now, we start converting tty buffer functions to actually use
tty_port. This will allow us to get rid of the need of tty in many
call sites. Only tty_port will needed and hence no more
tty_port_tty_get in those paths.

Now, the one where most of tty_port_tty_get gets removed:
tty_flip_buffer_push.

IOW we also closed all the races in drivers not using tty_port_tty_get
at all yet.

Also we move tty_flip_buffer_push declaration from include/linux/tty.h
to include/linux/tty_flip.h to all others while we are changing it
anyway.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-15 22:30:15 -08:00
Jiri Slaby 05c7cd3990 TTY: switch tty_insert_flip_string
Now, we start converting tty buffer functions to actually use
tty_port. This will allow us to get rid of the need of tty in many
call sites. Only tty_port will needed and hence no more
tty_port_tty_get in those paths.

tty_insert_flip_string this time.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-15 22:22:35 -08:00
Linus Walleij de60958207 serial/amba-pl011: use devm_* managed resources
This switches a bunch of allocation and remapping to use the
devm_* garbage collected methods and cleans up the error
path and remove() paths consequently.

devm_ioremap() is only in <linux/io.h> so fix up the
erroneous <asm/*> include as well.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Domenico Andreoli <domenico.andreoli@linux.com>
Acked-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-25 11:29:44 -07:00
Anton Vorontsov 5c8124a0f8 tty/serial/amba-pl011: Quiesce interrupts in poll_get_char
We need to quiesce interrupts in the poll_get_char routine, otherwise,
if used with KGDB NMI debugger, we'll keep reentering the NMI.

Quiescing interrupts is pretty straightforward, except for TXIM
interrupt. The interrupt has "ready to transmit" meaning, so it's
almost always raised, and the only way to silence it is to mask it. But
that's OK, ops->start_tx will unmask it.

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 13:51:32 -07:00
Anton Vorontsov b3564c2cf4 tty/serial/amba-pl011: Implement poll_init callback
The callback is used to initialize the hardware, nothing else should be
done, i.e. we should not request interrupts (but we can and do unmask
some of them, as they might be useful for NMI entry).

As a side-effect, the patch also fixes a division by zero[1] when booting
with kgdboc options specified (e.g. kgdboc=ttyAMA0,115200n8). The issue
happens because serial core calls set_termios callback, but the driver
doesn't know clock frequency, and thus cannot calculate proper baud rate
values.

[1]
WARNING: at drivers/tty/serial/serial_core.c:400 uart_get_baud_rate+0xe8/0x14c()
Modules linked in:
[<c0018e50>] (unwind_backtrace+0x0/0xf0) from [<c0020ae8>] (warn_slowpath_common+0x4c/0x64)
[<c0020ae8>] (warn_slowpath_common+0x4c/0x64) from [<c0020b1c>] (warn_slowpath_null+0x1c/0x24)
[<c0020b1c>] (warn_slowpath_null+0x1c/0x24) from [<c0185ed8>] (uart_get_baud_rate+0xe8/0x14c)
[<c0185ed8>] (uart_get_baud_rate+0xe8/0x14c) from [<c0187078>] (pl011_set_termios+0x48/0x278)
[<c0187078>] (pl011_set_termios+0x48/0x278) from [<c01850b0>] (uart_set_options+0xe8/0x114)
[<c01850b0>] (uart_set_options+0xe8/0x114) from [<c0185de4>] (uart_poll_init+0xd4/0xe0)
[<c0185de4>] (uart_poll_init+0xd4/0xe0) from [<c016da8c>] (tty_find_polling_driver+0x100/0x17c)
[<c016da8c>] (tty_find_polling_driver+0x100/0x17c) from [<c0188538>] (configure_kgdboc+0xc8/0x1b8)
[<c0188538>] (configure_kgdboc+0xc8/0x1b8) from [<c00088a4>] (do_one_initcall+0x30/0x168)
[<c00088a4>] (do_one_initcall+0x30/0x168) from [<c033784c>] (do_basic_setup+0x94/0xc8)
[<c033784c>] (do_basic_setup+0x94/0xc8) from [<c03378e0>] (kernel_init+0x60/0xf4)
[<c03378e0>] (kernel_init+0x60/0xf4) from [<c00144a0>] (kernel_thread_exit+0x0/0x8)
---[ end trace 7d41c9186f342c40 ]---
Division by zero in kernel.
[<c0018e50>] (unwind_backtrace+0x0/0xf0) from [<c014546c>] (Ldiv0+0x8/0x10)
[<c014546c>] (Ldiv0+0x8/0x10) from [<c0187098>] (pl011_set_termios+0x68/0x278)
[<c0187098>] (pl011_set_termios+0x68/0x278) from [<c01850b0>] (uart_set_options+0xe8/0x114)
[<c01850b0>] (uart_set_options+0xe8/0x114) from [<c0185de4>] (uart_poll_init+0xd4/0xe0)
[<c0185de4>] (uart_poll_init+0xd4/0xe0) from [<c016da8c>] (tty_find_polling_driver+0x100/0x17c)
[<c016da8c>] (tty_find_polling_driver+0x100/0x17c) from [<c0188538>] (configure_kgdboc+0xc8/0x1b8)
[<c0188538>] (configure_kgdboc+0xc8/0x1b8) from [<c00088a4>] (do_one_initcall+0x30/0x168)
[<c00088a4>] (do_one_initcall+0x30/0x168) from [<c033784c>] (do_basic_setup+0x94/0xc8)
[<c033784c>] (do_basic_setup+0x94/0xc8) from [<c03378e0>] (kernel_init+0x60/0xf4)
[<c03378e0>] (kernel_init+0x60/0xf4) from [<c00144a0>] (kernel_thread_exit+0x0/0x8)
Division by zero in kernel.
[<c0018e50>] (unwind_backtrace+0x0/0xf0) from [<c014546c>] (Ldiv0+0x8/0x10)
[<c014546c>] (Ldiv0+0x8/0x10) from [<c0183a98>] (uart_update_timeout+0x4c/0x5c)
[<c0183a98>] (uart_update_timeout+0x4c/0x5c) from [<c01870f8>] (pl011_set_termios+0xc8/0x278)
[<c01870f8>] (pl011_set_termios+0xc8/0x278) from [<c01850b0>] (uart_set_options+0xe8/0x114)
[<c01850b0>] (uart_set_options+0xe8/0x114) from [<c0185de4>] (uart_poll_init+0xd4/0xe0)
[<c0185de4>] (uart_poll_init+0xd4/0xe0) from [<c016da8c>] (tty_find_polling_driver+0x100/0x17c)
[<c016da8c>] (tty_find_polling_driver+0x100/0x17c) from [<c0188538>] (configure_kgdboc+0xc8/0x1b8)
[<c0188538>] (configure_kgdboc+0xc8/0x1b8) from [<c00088a4>] (do_one_initcall+0x30/0x168)
[<c00088a4>] (do_one_initcall+0x30/0x168) from [<c033784c>] (do_basic_setup+0x94/0xc8)
[<c033784c>] (do_basic_setup+0x94/0xc8) from [<c03378e0>] (kernel_init+0x60/0xf4)
[<c03378e0>] (kernel_init+0x60/0xf4) from [<c00144a0>] (kernel_thread_exit+0x0/0x8)

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 13:51:31 -07:00
Linus Walleij c5dd553b9f serial: pl011: handle corruption at high clock speeds
This works around a few glitches in the ST version of the PL011
serial driver when using very high baud rates, as we do in the
Ux500: 3, 3.25, 4 and 4.05 Mbps.

Problem Observed/rootcause:

When using high baud-rates, and the baudrate*8 is getting close to
the provided clock frequency (so a division factor close to 1), when
using bursts of characters (so they are abutted), then it seems as if
there is not enough time to detect the beginning of the start-bit which
is a timing reference for the entire character, and thus the sampling
moment of character bits is moving towards the end of each bit, instead
of the middle.

Fix:
Increase slightly the RX baud rate of the UART above the theoretical
baudrate by 5%. This will definitely give more margin time to the
UART_RX to correctly sample the data at the middle of the bit period.

Also fix the ages old copy-paste error in the very stressed comment,
it's referencing the registers used in the PL010 driver rather than
the PL011 ones.

Signed-off-by: Guillaume Jaunet <guillaume.jaunet@stericsson.com>
Signed-off-by: Christophe Arnal <christophe.arnal@stericsson.com>
Signed-off-by: Matthias Locher <matthias.locher@stericsson.com>
Signed-off-by: Rajanikanth HV <rajanikanth.hv@stericsson.com>
Cc: stable <stable@vger.kernel.org>
Cc: Bibek Basu <bibek.basu@stericsson.com>
Cc: Par-Gunnar Hjalmdahl <par-gunnar.hjalmdahl@stericsson.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-09-26 13:41:05 -07:00
Linus Walleij fe0ed5b315 serial: pl011: delete dangling bug flag
The bug flag .interrupt_may_hang is not used since commit
4fd0690bb0
"serial: pl011: implement workaround for CTS clear event issue"
so delete it.

Cc: Rajanikanth H.V <rajanikanth.hv@stericsson.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-09-10 16:33:02 -07:00
Matthew Leach 32614aad30 serial: pl011: honour serial aliases in device tree
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: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Will Deacon <will.deacon@arm.com>
Acked-by: Rob Herring <rob.herring@calxeda.com>
Signed-off-by: Matthew Leach <matthew.leach@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-09-05 13:18:12 -07:00
Julia Lawall 1c4c4394a6 drivers/tty/serial/amba-pl0{10,11}.c: use clk_prepare_enable and clk_disable_unprepare
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: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-09-05 12:33:39 -07:00
Greg Kroah-Hartman c87985a3ce Merge tty-next into 3.6-rc1
This handles the merge issue in:
	arch/um/drivers/line.c
	arch/um/drivers/line.h
And resolves the duplicate patches that were in both trees do to the
tty-next branch not getting merged into 3.6-rc1.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-08-06 09:48:31 -07:00
Russell King 91b006def3 Merge branches 'audit', 'delay', 'fixes', 'misc' and 'sta2x11' into for-linus 2012-07-27 23:06:32 +01:00
Alessandro Rubini cb70706c82 ARM: 7433/1: serial: use the new linux/sizes.h
Signed-off-by: Alessandro Rubini <rubini@gnudd.com>
Acked-by: Giancarlo Asnaghi <giancarlo.asnaghi@st.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-06-28 17:14:36 +01:00