Commit Graph

162 Commits

Author SHA1 Message Date
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
Greg Kroah-Hartman fc915c8b93 Merge 3.5-rc4 into tty-next
This is to pick up the serial port and tty changes in Linus's tree to allow
everyone to sync up.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-06-26 16:04:29 -07:00
Linus Walleij e643f87f71 serial/amba-pl011: fix ages old copy-paste errors
The PL011 driver has a number of symbols referring to "pl01x"
(probably once shared with the pl010 driver) and some even named
"pl010" (probably a pure copy-paste artifact). Lets name all
local static functions with the prefix pl011_* for clarity.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-06-18 17:34:08 -07:00
Linus Walleij 78d80c5a72 serial/amba-pl011: move custom pin control to driver
We had a boot regression in Ux500 in the merge window because
two orthogonal pin control schemes for the PL011 were merged
at the same time:

- One using the .init() and .exit() hooks into the platform
  for Ux500 putting the pins into default vs sleep state
  respectively as the port was started/stopped.
  commit a09806607f
  "ARM: ux500: switch to using pinctrl for uart0"

- One hogging the default setting at PL011 probe()
  commit 258e055111
  "serial: amba-pl011: adopt pinctrl support"

To get a solution that works for both let's scrap the stuff
in the platform callbacks, instead have the driver itself
select default and sleep states when the port is
started/stopped. Hopefully this works for all clients.
Platform callbacks are bad for device tree migration anyway,
so this rids us of another problem in Ux500.

Cc: Shawn Guo <shawn.guo@linaro.org>
Cc: Russell King <rmk+kernel@arm.linux.org.uk>
Reported-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-06-12 15:41:44 -07:00
Linus Torvalds 94b5aff4c6 TTY pull request for 3.5-rc1
Here's the big TTY/serial driver pull request for the 3.5-rc1 merge window.
 
 Nothing major in here, just lots of incremental changes from Alan and
 Jiri reworking some tty core things to behave better and to get a more
 solid grasp on some of the nasty tty locking issues.
 
 There are a few tty and serial driver updates in here as well.
 
 All of this has been in the linux-next releases for a while with no problems.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'tty-3.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Pull TTY updates from Greg Kroah-Hartman:
 "Here's the big TTY/serial driver pull request for the 3.5-rc1 merge
  window.

  Nothing major in here, just lots of incremental changes from Alan and
  Jiri reworking some tty core things to behave better and to get a more
  solid grasp on some of the nasty tty locking issues.

  There are a few tty and serial driver updates in here as well.

  All of this has been in the linux-next releases for a while with no
  problems.

  Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>"

* tag 'tty-3.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (115 commits)
  serial: bfin_uart: Make MMR access compatible with 32 bits bf609 style controller.
  serial: bfin_uart: RTS and CTS MMRs can be either 16-bit width or 32-bit width.
  serial: bfin_uart: narrow the reboot condition in DMA tx interrupt
  serial: bfin_uart: Adapt bf5xx serial driver to bf60x serial4 controller.
  Revert "serial_core: Update buffer overrun statistics."
  tty: hvc_xen: NULL dereference on allocation failure
  tty: Fix LED error return
  tty: Allow uart_register/unregister/register
  tty: move global ldisc idle waitqueue to the individual ldisc
  serial8250-em: Add DT support
  serial8250-em: clk_get() IS_ERR() error handling fix
  serial_core: Update buffer overrun statistics.
  tty: drop the pty lock during hangup
  cris: fix missing tty arg in wait_event_interruptible_tty call
  tty/amiserial: Add missing argument for tty_unlock()
  tty_lock: Localise the lock
  pty: Lock the devpts bits privately
  tty_lock: undo the old tty_lock use on the ctty
  serial8250-em: Emma Mobile UART driver V2
  Add missing call to uart_update_timeout()
  ...
2012-05-22 16:12:24 -07:00
Shawn Guo 258e055111 serial: amba-pl011: adopt pinctrl support
Cc: linux-serial@vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-05-12 09:43:12 +08:00
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
Rajanikanth H.V 4fd0690bb0 serial: pl011: implement workaround for CTS clear event issue
Problem Observed:
- interrupt status is set by rising or falling edge on CTS line
- interrupt status is cleared on a .0. to .1. transition of the
  interrupt-clear register bit 1.
- interrupt-clear register is reset by hardware once the interrupt
  status is .0..
  Remark: It seems not possible to read this register back by the
  CPU though, but internally this register exists.
- when simultaneous set and reset event on the interrupt status
  happens, then the set-event has priority and the status remains
  .1.. As a result the interrupt-clear register is not reset to
  .0., and no new .0. to .1. transition can be detected on it when
  writing a .1. to it.
  This implies race condition, the clear must be performed at least
  one UARTCLK the riding edge of CTS RIS interrupt.

Fix:
  Instead of resetting UART as done in commit
  c16d51a32b
  "amba pl011: workaround for uart registers lockup" do the
  following:

  write .0. and then  .1. to the interrupt-clear register to make
  sure that this transition is detected. According to the datasheet
  writing a .0. does not have any effect, but actually it allows to
  reset the internal interrupt-clear register.

  Take into account:
  The .0. needs to last at least for one clk_uart clock period
  (~ 38 MHz, 26.08ns)

This way we can do away with the tasklet and keep only a tiny
fix triggered by the variant flag introduced in this patch.

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 H.V <rajanikanth.hv@stericsson.com>
Reviewed-by: Srinidhi Kasagar <srinidhi.kasagar@stericsson.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-04-18 15:06:38 -07:00
Linus Walleij c3d8b76f61 serial: PL011: move interrupt clearing
Commit 360f748b204275229f8398cb2f9f53955db1503b
"serial: PL011: clear pending interrupts"
attempts to clear interrupts by writing to a
yet-unassigned memory address. This fixes the issue.

The breaking patch is marked for stable so should be
carried along with the other patch.

Cc: Shreshtha Kumar Sahu <shreshthakumar.sahu@stericsson.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: stable <stable@vger.kernel.org>
Cc: Nicolas Pitre <nico@fluxnic.net>
Reported-by: Viresh Kumar <viresh.kumar@st.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-04-06 14:04:33 -07:00
Linus Torvalds ef08e78268 Merge branch 'next' of git://git.infradead.org/users/vkoul/slave-dma
Pull slave-dmaengine update from Vinod Koul:
 "This includes the cookie cleanup by Russell, the addition of context
  parameter for dmaengine APIs, more arm dmaengine driver cleanup by
  moving code to dmaengine, this time for imx by Javier and pl330 by
  Boojin along with the usual driver fixes."

Fix up some fairly trivial conflicts with various other cleanups.

* 'next' of git://git.infradead.org/users/vkoul/slave-dma: (67 commits)
  dmaengine: imx: fix the build failure on x86_64
  dmaengine: i.MX: Fix merge of cookie branch.
  dmaengine: i.MX: Add support for interleaved transfers.
  dmaengine: imx-dma: use 'dev_dbg' and 'dev_warn' for messages.
  dmaengine: imx-dma: remove 'imx_dmav1_baseaddr' and 'dma_clk'.
  dmaengine: imx-dma: remove unused arg of imxdma_sg_next.
  dmaengine: imx-dma: remove internal structure.
  dmaengine: imx-dma: remove 'resbytes' field of 'internal' structure.
  dmaengine: imx-dma: remove 'in_use' field of 'internal' structure.
  dmaengine: imx-dma: remove sg member from internal structure.
  dmaengine: imx-dma: remove 'imxdma_setup_sg_hw' function.
  dmaengine: imx-dma: remove 'imxdma_config_channel_hw' function.
  dmaengine: imx-dma: remove 'imxdma_setup_mem2mem_hw' function.
  dmaengine: imx-dma: remove dma_mode member of internal structure.
  dmaengine: imx-dma: remove data member from internal structure.
  dmaengine: imx-dma: merge old dma-v1.c with imx-dma.c
  dmaengine: at_hdmac: add slave config operation
  dmaengine: add context parameter to prep_slave_sg and prep_dma_cyclic
  dmaengine/dma_slave: introduce inline wrappers
  dma: imx-sdma: Treat firmware messages as warnings instead of erros
  ...
2012-03-29 15:34:57 -07:00
Alexandre Bounine 16052827d9 dmaengine/dma_slave: introduce inline wrappers
Add inline wrappers for device_prep_slave_sg() and device_prep_dma_cyclic()
interfaces to hide new parameter from current users of affected interfaces.
Convert current users to use new wrappers instead of direct calls.
Suggested by Russell King [https://lkml.org/lkml/2012/2/3/269].

Signed-off-by: Alexandre Bounine <alexandre.bounine@idt.com>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
2012-03-21 19:20:22 +05:30
Linus Walleij 9b96fbacda serial: PL011: clear pending interrupts
Chanho Min reported that when the boot loader transfers
control to the kernel, there may be pending interrupts
causing the UART to lock up in an eternal loop trying to
pick tokens from the FIFO (since the RX interrupt flag
indicates there are tokens) while in practice there are
no tokens - in fact there is only a pending IRQ flag.

This patch address the issue with a combination of two
patches suggested by Russell King that clears and mask
all interrupts at probe() and clears any pending error
and RX interrupts at port startup time.

We suspect the spurious interrupts are a side-effect of
switching the UART from FIFO to non-FIFO mode.

Cc: Shreshtha Kumar Sahu <shreshthakumar.sahu@stericsson.com>
Reported-by: Chanho Min <chanho0207@gmail.com>
Suggested-by: Russell King <linux@arm.linux.org.uk>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Jong-Sung Kim <neidhard.kim@lge.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-03-14 12:27:39 -07:00
Chanho Min 6dc01aa653 amba-pl011​/dma: Add check for the residue in DMA callback
In DMA-operated uart, I found that rx data can be taken by the UART
interrupts during the DMA irq handler. pl011_int is occurred just
before it goes inside spin_lock_irq. When it returns to the callback,
DMA buffer already has been flushed. Then, pl011_dma_rx_chars gets
invalid data. So I add check for the residue as the patch bellow.

Signed-off-by: Chanho Min <chanho.min@lge.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-02-24 13:50:47 -08:00
Viresh Kumar 258aea76f5 dmaengine: Pass dma_slave_config .device_fc = NULL for all existing users
.device_fc is added in struct dma_slave_config recently. All user drivers, which
want DMA to be the flow controller must pass this field as false. As earlier
driver don't look to use this feature, mark it false for now.

Signed-off-by: Viresh Kumar <viresh.kumar@st.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
2012-02-22 18:15:37 +05:30
Rabin Vincent ef605fdb33 serial: amba-pl011: lock console writes against interrupts
Protect against pl011_console_write() and the interrupt for
the console UART running concurrently on different CPUs.

Otherwise the console_write could spin for a long time
waiting for the UART to become not busy, while the other
CPU continuously services UART interrupts and keeps the
UART busy.

The checks for sysrq and oops_in_progress are taken
from 8250.c.

Cc: stable <stable@vger.kernel.org>
Signed-off-by: Rabin Vincent <rabin.vincent@stericsson.com>
Reviewed-by: Srinidhi Kasagar <srinidhi.kasagar@stericsson.com>
Reviewed-by: Bibek Basu <bibek.basu@stericsson.com>
Reviewed-by: Shreshtha Kumar Sahu <shreshthakumar.sahu@stericsson.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2012-01-24 16:09:55 -08:00
Shreshtha Kumar Sahu d8d8ffa477 amba-pl011: do not disable RTS during shutdown
In present driver, shutdown clears RTS and DTR in CR register. But the
documentation "Documentation/serial/driver" suggests not to disable
RTS and DTR in shutdown(). Also RTS and DTR is preserved between shutdown
and startup calls, i.e. these are restored in startup if they were enabled
while doing shutdown. So that if RTS and DTR are set using pl011_set_mctrl
then it should continue even after shutdown->startup sequence.
For throttling/unthrottling user should call pl011_set_mctrl.

Signed-off-by: Shreshtha Kumar Sahu <shreshthakumar.sahu@stericsson.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2012-01-24 16:09:55 -08:00
Linus Torvalds 57f2685c16 Merge branch 'next' of git://git.infradead.org/users/vkoul/slave-dma
* 'next' of git://git.infradead.org/users/vkoul/slave-dma: (53 commits)
  ARM: mach-shmobile: specify CHCLR registers on SH7372
  dma: shdma: fix runtime PM: clear channel buffers on reset
  dma/imx-sdma: save irq flags when use spin_lock in sdma_tx_submit
  dmaengine/ste_dma40: clear LNK on channel startup
  dmaengine: intel_mid_dma: remove legacy pm interface
  ASoC: mxs: correct 'direction' of device_prep_dma_cyclic
  dmaengine: intel_mid_dma: error path fix
  dmaengine: intel_mid_dma: locking and freeing fixes
  mtd: gpmi-nand: move to dma_transfer_direction
  mtd: fix compile error for gpmi-nand
  mmc: mxs-mmc: fix the dma_transfer_direction migration
  dmaengine: add DMA_TRANS_NONE to dma_transfer_direction
  dma: mxs-dma: Don't use CLKGATE bits in CTRL0 to disable DMA channels
  dma: mxs-dma: make mxs_dma_prep_slave_sg() multi user safe
  dma: mxs-dma: Always leave mxs_dma_init() with the clock disabled.
  dma: mxs-dma: fix a typo in comment
  DMA: PL330: Remove pm_runtime_xxx calls from pl330 probe/remove
  video i.MX IPU: Fix display connections
  i.MX IPU DMA: Fix wrong burstsize settings
  dmaengine/ste_dma40: allow fixed physical channel
  ...

Fix up conflicts in drivers/dma/{Kconfig,mxs-dma.c,pl330.c}

The conflicts looked pretty trivial, but I'll ask people to verify them.
2012-01-17 18:40:24 -08:00
Dave Martin 60f7a33b82 serial: pl011: Enable module alias autogeneration for AMBA drivers
Signed-off-by: Dave Martin <dave.martin@linaro.org>
2011-11-22 10:58:32 +00:00
Vinod Koul e0d23ef29e Merge branch 'dma_slave_direction' into next_test_dirn
resolved conflicts:
	drivers/media/video/mx3_camera.c
2011-11-17 14:54:57 +05:30
Vinod Koul a485df4b44 spi, serial: move to dma_transfer_direction
fixup usage of dma direction by introducing dma_transfer_direction,
this patch moves spi, serial drivers to use new enum

Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: Alan Cox <alan@linux.intel.com>
Acked-by: Mika Westerberg <mika.westerberg@iki.fi>
2011-10-31 09:40:26 +05:30
Russell King 4b4851c65d clk: amba-pl011: convert to clk_prepare()/clk_unprepare()
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-09-27 09:25:52 +01:00
Shreshtha Kumar Sahu c16d51a32b amba pl011: workaround for uart registers lockup
This workaround aims to break the deadlock situation
which raises during continuous transfer of data for long
duration over uart with hardware flow control. It is
observed that CTS interrupt cannot be cleared in uart
interrupt register (ICR). Hence further transfer over
uart gets blocked.

It is seen that during such deadlock condition ICR
don't get cleared even on multiple write. This leads
pass_counter to decrease and finally reach zero. This
can be taken as trigger point to run this UART_BT_WA.

Workaround backups the register configuration, does soft
reset of UART using BIT-0 of PRCC_K_SOFTRST_SET/CLEAR
registers and restores the registers.

This patch also provides support for uart init and exit
function calls if present.

Signed-off-by: Shreshtha Kumar Sahu <shreshthakumar.sahu@stericsson.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-06-16 12:01:57 -07:00
Jovi Zhang 99edb3d10a tty: remove invalid location line in file header
remove invalid location line in each file header after location
moved from driver/char to driver/tty

Signed-off-by: Jovi Zhang <bookjovi@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-04-19 16:33:36 -07:00
Lucas De Marchi 25985edced Fix common misspellings
Fixes generated by 'codespell' and manually reviewed.

Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
2011-03-31 11:26:23 -03:00
Russell King 9c9585e0e9 Merge branches 'aaci', 'mmci-dma', 'pl' and 'pl011' into drivers 2011-03-17 11:04:51 +00:00
Linus Walleij 29772c4e28 ARM: 6764/1: pl011: factor out FIFO to TTY code
This piece of code was just slightly different between the DMA
and IRQ paths, in DMA mode we surely shouldn't read more than
256 character either, so factor this out in its own function and
use for both DMA and PIO mode.

Tested on Ux500 and U300.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-03-10 10:07:24 +00:00
Linus Walleij ead76f329f ARM: 6763/1: pl011: add optional RX DMA to PL011 v2
This adds an optional RX DMA codepath for the devices that
support this by using the apropriate burst sizes instead of
pulling single bytes.

Includes portions of code written by Russell King during
a PL08x hacking session.

This has been tested on U300 and Ux500.

Tested-by: Jerzy Kasenberg <jerzy.kasenberg@tieto.com>
Tested-by: Grzegorz Sygieda <grzegorz.sygieda@tieto.com>
Tested-by: Marcin Mielczarczyk <marcin.mielczarczyk@tieto.com>
Signed-off-by: Per Forlin <per.friden@stericsson.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-03-10 10:07:22 +00:00
Russell King aa25afad2c ARM: amba: make probe() functions take const id tables
Make Primecell driver probe functions take a const pointer to their
ID tables.  Drivers should never modify their ID tables in their
probe handler.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-02-23 16:24:14 +00:00
Greg Kroah-Hartman ab4382d274 tty: move drivers/serial/ to drivers/tty/serial/
The serial drivers are really just tty drivers, so move them to
drivers/tty/ to make things a bit neater overall.

This is part of the tty/serial driver movement proceedure as proposed by
Arnd Bergmann and approved by everyone involved a number of months ago.

Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Rogier Wolff <R.E.Wolff@bitwizard.nl>
Cc: Michael H. Warfield <mhw@wittsend.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-01-13 12:10:18 -08:00