Commit Graph

363 Commits

Author SHA1 Message Date
Lukas Wunner
eec1d566cd gpio: Introduce ->get_multiple callback
SPI-attached GPIO controllers typically read out all inputs in one go.
If callers desire the values of multipe inputs, ideally a single readout
should take place to return the desired values.  However the current
driver API only offers a ->get callback but no ->get_multiple (unlike
->set_multiple, which is present).  Thus, to read multiple inputs, a
full readout needs to be performed for every single value (barring
driver-internal caching), which is inefficient.

In fact, the lack of a ->get_multiple callback has been bemoaned
repeatedly by the gpio subsystem maintainer:
http://www.spinics.net/lists/linux-gpio/msg10571.html
http://www.spinics.net/lists/devicetree/msg121734.html

Introduce the missing callback.  Add corresponding consumer functions
such as gpiod_get_array_value().  Amend linehandle_ioctl() to take
advantage of the newly added infrastructure.  Update the documentation.

Cc: Rojhalat Ibrahim <imr@rtschenk.de>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-10-19 22:32:39 +02:00
Linus Walleij
02e479808b gpio: Alter semantics of *raw* operations to actually be raw
Currently calls to:
gpiod_direction_output_raw()
gpiod_set_raw_value()
gpiod_set_raw_array_value()
gpiod_set_raw_value_cansleep()
gpiod_set_raw_array_value_cansleep()

Respect that we do not want to invert the value written, but will
still apply special open drain/open source semantics if the line has
an open drain/open source flag.

It also forbids us from driving an output marked as an interrupt
line.

This does not fit with the function name and expected semantics. In
the w1 host driver (for example) we need to handle a line as open drain
but sometimes force it to pull up, which means we should be able to
use the gpiod_set_raw_value() for this, but it currently does not
work.

There are also use cases where users actually want to drive a line
used by an interrupt. This is what they should be expected to use
the *raw* accessors for.

I have looked over the current users of this API and they do not seem
to be using the *raw* accessors with open drain or open source so let's
augment this behaviour before we have users expecting the inconsistent
semantic.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-10-04 08:38:02 +02:00
Linus Walleij
fac9d8850a gpio: Get rid of _prefix and __prefixes
The arbitrarily marking of a function with _ or __ is taking to mean
"perform some inner core of the caller" or something like that. At other
times, this syntax has a totally different meaning.

I don't like this since it is unambious and unhelpful to people reading
the code, so replace it with _commit() suffixes.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-10-04 08:37:47 +02:00
Linus Walleij
9e238e380c Revert "gpiolib: request the gpio before querying its direction"
This reverts commit 108d23e322.
It turns out this causes a regression on the OMAP, Marvell
and Renesas.

Reported-by: Tony Lindgren <tony@atomide.com>
Reported-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Reported-by: Jacopo Mondi <jacopo@jmondi.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-08-31 09:05:30 +02:00
Dmitry Torokhov
3946d18765 gpio: add gpio_add_lookup_tables() to add several tables at once
When converting legacy board to use gpiod API() there might be several
lookup tables in board file, let's provide a way to register them all at
once.

Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-08-23 09:16:35 +02:00
Thierry Reding
950d55f5bf gpio: Cleanup kerneldoc
Some kerneldoc has become stale or wasn't quite correct from the outset.
Fix up the most serious issues to silence warnings when building the
documentation.

Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-08-14 15:01:13 +02:00
Rob Herring
7eb6ce2f27 gpio: Convert to using %pOF instead of full_name
Now that we have a custom printf format specifier, convert users of
full_name to use %pOF instead. This is preparation to remove storing
of the full path string for each node.

Signed-off-by: Rob Herring <robh@kernel.org>
Cc: Tien Hock Loh <thloh@altera.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Alexandre Courbot <gnurou@gmail.com>
Cc: Brian Norris <computersforpeace@gmail.com>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: bcm-kernel-feedback-list@broadcom.com
Cc: Michal Simek <michal.simek@xilinx.com>
Cc: "Sören Brinkmann" <soren.brinkmann@xilinx.com>
Cc: linux-gpio@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Acked-by: Gregory Fong <gregory.0xf0@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-08-14 15:01:12 +02:00
Grygorii Strashko
dc749a09ea gpiolib: allow gpio irqchip to map irqs dynamically
Now IRQ mappings are always created for all (allowed) GPIOs in gpiochip in
gpiochip_irqchip_add_key() which goes against the idea of SPARSE_IRQ and,
as result, leads to:
 - increasing of memory consumption for IRQ descriptors most of which will
never ever be used (espessially on platform with a high number of GPIOs).
(sizeof(struct irq_desc) == 256 on my tested platforms)
 - imposibility to use GPIO irqchip APIs by gpio drivers when HW implements
GPIO IRQ functionality as IRQ crossbar/router which has only limited
number of IRQ outputs (example from [1], all GPIOs can be mapped on only 8
IRQs).

Hence, remove static IRQ mapping code from gpiochip_irqchip_add_key() and
instead replace irq_find_mapping() with irq_create_mapping() in
gpiochip_to_irq(). Also add additional gpiochip_irqchip_irq_valid() calls
in gpiochip_to_irq() and gpiochip_irq_map().

After this change gpio2irq mapping will happen the following way when GPIO
irqchip APIs are used by gpio driver:
 - IRQ mappings will be created statically if driver passes first_irq>0
vlaue in gpiochip_irqchip_add_key().
 - IRQ mappings will be created dynamically from gpio_to_irq() or
of_irq_get().

Tested on am335x-evm and dra72-evm-revc.
- dra72-evm-revc: number of created irq mappings decreased from 402 -> 135
  Mem savings 267*256 = 68352 (66kB)
- am335x-evm: number of created irq mappings decreased from 188 -> 63
  Mem savings 125*256 = 32000 (31kB)

[1] https://lkml.org/lkml/2017/6/15/428

Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-08-14 15:01:12 +02:00
Timur Tabi
108d23e322 gpiolib: request the gpio before querying its direction
Before querying a GPIO to determine its direction, the GPIO should be
formally requested.  This allows the GPIO driver to block access to
unavailable GPIOs, which makes it easier for some drivers to support
sparse GPIO maps.

Signed-off-by: Timur Tabi <timur@codeaurora.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-08-14 15:01:12 +02:00
Bartosz Golaszewski
df1e76f28f gpiolib: skip unwanted events, don't convert them to opposite edge
The previous fix for filtering out of unwatched events was not entirely
correct. Instead of skipping the events we don't want, they are now
interpreted as events with opposing edge.

In order to fix it: always read the GPIO line value on interrupt and
only emit the event if it corresponds with the event type we requested.

Cc: stable@vger.kernel.org
Fixes: ad537b8225 ("gpiolib: fix filtering out unwanted events")
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-08-01 14:07:35 +02:00
Linus Torvalds
c7d28eca1d This is the bulk of GPIO changes for the v4.13 series:
Core:
 - Export add/remove for lookup tables so that modules can export GPIO
   descriptor tables.
 - Handle GPIO sleep states: it is now possible to flag that a GPIO line
   may loose its state during suspend/resume of the system to save
   power. This is used in the Wolfson Micro Arizona driver.
 - ACPI-based GPIO was tightened up a lot around the edges.
 - Use bitmap_fill() to speed up a loop.
 
 New drivers:
 - Exar XRA1403 SPI-based GPIO.
 - MVEBU driver now supports Armada 7K and 8K.
 - LP87565 PMIC GPIO.
 - Renesas R-CAR R8A7743 (RZ/G1M).
 - The new IOT2040 8250 serial/GPIO also comes in through this
   changeset.
 
 Substantial driver changes:
 - Seriously fix the Exar 8250 GPIO portions to work.
 - The MCP23S08 was moved out to a pin control driver.
 - Convert MEVEBU to use regmap for register access.
 - Drop Vulcan support from the Broadcom driver.
 - Serious cleanup and improvement of the mockup driver, giving us a
   better test coverage.
 
 Misc:
 - Lots of janitorial clean up.
 - A bunch of documentation fixes.
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Merge tag 'gpio-v4.13-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio

Pull GPIO updates from Linus Walleij:
 "This is the bulk of GPIO changes for the v4.13 series.

  Some administrativa:

  I have a slew of 8250 serial patches and the new IOT2040 serial+GPIO
  driver coming in through this tree, along with a whole bunch of Exar
  8250 fixes. These are ACKed by Greg and also hit drivers/platform/*
  where they are ACKed by Andy Shevchenko.

  Speaking about drivers/platform/* there is also a bunch of ACPI stuff
  coming through that route, again ACKed by Andy.

  The MCP23S08 changes are coming in here as well. You already have the
  commits in your tree, so this is just a result of sharing an immutable
  branch between pin control and GPIO.

  Core:
   - Export add/remove for lookup tables so that modules can export GPIO
     descriptor tables.
   - Handle GPIO sleep states: it is now possible to flag that a GPIO
     line may loose its state during suspend/resume of the system to
     save power. This is used in the Wolfson Micro Arizona driver.
   - ACPI-based GPIO was tightened up a lot around the edges.
   - Use bitmap_fill() to speed up a loop.

  New drivers:
   - Exar XRA1403 SPI-based GPIO.
   - MVEBU driver now supports Armada 7K and 8K.
   - LP87565 PMIC GPIO.
   - Renesas R-CAR R8A7743 (RZ/G1M).
   - The new IOT2040 8250 serial/GPIO also comes in through this
     changeset.

  Substantial driver changes:
   - Seriously fix the Exar 8250 GPIO portions to work.
   - The MCP23S08 was moved out to a pin control driver.
   - Convert MEVEBU to use regmap for register access.
   - Drop Vulcan support from the Broadcom driver.
   - Serious cleanup and improvement of the mockup driver, giving us a
     better test coverage.

  Misc:
   - Lots of janitorial clean up.
   - A bunch of documentation fixes"

* tag 'gpio-v4.13-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (70 commits)
  serial: exar: Add support for IOT2040 device
  gpio-exar/8250-exar: Make set of exported GPIOs configurable
  platform: Accept const properties
  serial: exar: Factor out platform hooks
  gpio-exar/8250-exar: Rearrange gpiochip parenthood
  gpio: exar: Fix iomap request
  gpio-exar/8250-exar: Do not even instantiate a GPIO device for Commtech cards
  serial: uapi: Add support for bus termination
  gpio: rcar: Add R8A7743 (RZ/G1M) support
  gpio: gpio-wcove: Fix GPIO control register offset calculation
  gpio: lp87565: Add support for GPIO
  gpio: dwapb: fix missing first irq for edgeboth irq type
  MAINTAINERS: Take maintainership for GPIO ACPI support
  gpio: exar: Fix reading of directions and values
  gpio: exar: Allocate resources on behalf of the platform device
  gpio-exar/8250-exar: Fix passing in of parent PCI device
  gpio: mockup: use devm_kcalloc() where applicable
  gpio: mockup: add myself as author
  gpio: mockup: improve the error message
  gpio: mockup: don't return magic numbers from probe()
  ...
2017-07-07 12:40:27 -07:00
Bartosz Golaszewski
ad537b8225 gpiolib: fix filtering out unwanted events
GPIOEVENT_REQUEST_BOTH_EDGES is not a single flag, but a binary OR of
GPIOEVENT_REQUEST_RISING_EDGE and GPIOEVENT_REQUEST_FALLING_EDGE.

The expression 'le->eflags & GPIOEVENT_REQUEST_BOTH_EDGES' we'll get
evaluated to true even if only one event type was requested.

Fix it by checking both RISING & FALLING flags explicitly.

Cc: stable@vger.kernel.org
Fixes: 61f922db72 ("gpio: userspace ABI for reading GPIO line events")
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-06-29 11:33:46 +02:00
Arnd Bergmann
073570dcb5 gpiolib: remove unused variable
This was left behind by a cleanup patch:

drivers/gpio/gpiolib.c: In function 'gpiochip_irqchip_init_valid_mask':
drivers/gpio/gpiolib.c:1474:6: error: unused variable 'i' [-Werror=unused-variable]

Fixes: 923a654c18 ("gpiolib: Re-use bitmap_fill() instead of open coded loop")
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Reported-by: Colin King <colin.king@canonical.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-05-31 02:07:29 +02:00
Andy Shevchenko
923a654c18 gpiolib: Re-use bitmap_fill() instead of open coded loop
Re-use bitmap_fill() instead of open coded loop for setting an area of
bits in a bitmap.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-05-29 11:32:22 +02:00
Andy Shevchenko
a31f5c3a68 gpio: acpi: Override GPIO initialization flags
This allows ACPI GPIO code to modify flags based on
ACPI GpioIo() / GpioInt() resources.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Tested-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-05-29 11:21:44 +02:00
Andy Shevchenko
c29fd9ebb2 gpiolib: Export gpiod_configure_flags() to internal users
This is preparatory patch for enabling GPIO ACPI to configure a pin
accordingly.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Tested-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-05-29 11:14:52 +02:00
Charles Keepax
05f479bf7d gpio: Add new flags to control sleep status of GPIOs
Add new flags to allow users to specify that they are not concerned with
the status of GPIOs whilst in a sleep/low power state.

Signed-off-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-05-29 11:07:55 +02:00
Anatolij Gustschin
226b2242d4 gpio: export add/remove lookup table functions
For hot-pluggable devices adding GPIOs dynamically we need to
assemble and add the gpio lookup tables at probe time in modules,
so that requesting these GPIOs in attached drivers can work.
Export lookup table functions for modules.

Signed-off-by: Anatolij Gustschin <agust@denx.de>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-05-22 10:57:47 +02:00
Linus Torvalds
af82455f7d char/misc patches for 4.12-rc1
Here is the big set of new char/misc driver drivers and features for
 4.12-rc1.
 
 There's lots of new drivers added this time around, new firmware drivers
 from Google, more auxdisplay drivers, extcon drivers, fpga drivers, and
 a bunch of other driver updates.  Nothing major, except if you happen to
 have the hardware for these drivers, and then you will be happy :)
 
 All of these have been in linux-next for a while with no reported
 issues.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'char-misc-4.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc

Pull char/misc driver updates from Greg KH:
 "Here is the big set of new char/misc driver drivers and features for
  4.12-rc1.

  There's lots of new drivers added this time around, new firmware
  drivers from Google, more auxdisplay drivers, extcon drivers, fpga
  drivers, and a bunch of other driver updates. Nothing major, except if
  you happen to have the hardware for these drivers, and then you will
  be happy :)

  All of these have been in linux-next for a while with no reported
  issues"

* tag 'char-misc-4.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (136 commits)
  firmware: google memconsole: Fix return value check in platform_memconsole_init()
  firmware: Google VPD: Fix return value check in vpd_platform_init()
  goldfish_pipe: fix build warning about using too much stack.
  goldfish_pipe: An implementation of more parallel pipe
  fpga fr br: update supported version numbers
  fpga: region: release FPGA region reference in error path
  fpga altera-hps2fpga: disable/unprepare clock on error in alt_fpga_bridge_probe()
  mei: drop the TODO from samples
  firmware: Google VPD sysfs driver
  firmware: Google VPD: import lib_vpd source files
  misc: lkdtm: Add volatile to intentional NULL pointer reference
  eeprom: idt_89hpesx: Add OF device ID table
  misc: ds1682: Add OF device ID table
  misc: tsl2550: Add OF device ID table
  w1: Remove unneeded use of assert() and remove w1_log.h
  w1: Use kernel common min() implementation
  uio_mf624: Align memory regions to page size and set correct offsets
  uio_mf624: Refactor memory info initialization
  uio: Allow handling of non page-aligned memory regions
  hangcheck-timer: Fix typo in comment
  ...
2017-05-04 19:15:35 -07:00
Thierry Reding
6f79309acc gpio: Use unsigned int for interrupt numbers
Interrupt numbers are never negative, zero serves as the special invalid
value.

Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-04-13 14:16:23 +02:00
Laxman Dewangan
4c0facddb7 gpio: core: Decouple open drain/source flag with active low/high
Currently, the GPIO interface is said to Open Drain if it is Single
Ended and active LOW. Similarly, it is said as Open Source if it is
Single Ended and active HIGH.

The active HIGH/LOW is used in the interface for setting the pin
state to HIGH or LOW when enabling/disabling the interface.

In Open Drain interface, pin is set to HIGH by putting pin in
high impedance and LOW by driving to the LOW.

In Open Source interface, pin is set to HIGH by driving pin to
HIGH and set to LOW by putting pin in high impedance.

With above, the Open Drain/Source is unrelated to the active LOW/HIGH
in interface. There is interface where the enable/disable of interface
is ether active LOW or HIGH but it is Open Drain type.

Hence decouple the Open Drain with Single Ended + Active LOW and
Open Source with Single Ended + Active HIGH.

Adding different flag for the Open Drain/Open Source which is valid
only when Single ended flag is enabled.

Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-04-07 12:23:29 +02:00
Logan Gunthorpe
111379dccc gpiolib: utilize new cdev_device_add helper function
Replace the open coded registration of the cdev and dev with the
new device_add_cdev() helper. The helper replaces a common pattern by
taking the proper reference against the parent device and adding both
the cdev and the device.

Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-03-21 06:44:33 +01:00
Andy Shevchenko
4033d4a4f5 gpio: of: Don't return 0 on dt_gpio_count()
It's unusual to have error checking like (ret <= 0) in cases when
counting GPIO resources. In case when it's mandatory we propagate the
error (-ENOENT), otherwise we don't use the result.

This makes consistent behaviour across all possible variants called in
gpiod_count().

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-03-16 21:52:11 +01:00
Andy Shevchenko
ff21378a32 gpiolib: Fix spelling of 'successful'
Remove extra 'l' in "successfull".

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-03-14 10:51:28 +01:00
Linus Torvalds
1ec5c1867a This is the bulk of GPIO changes for the v4.11 cycle
Core changes:
 
 - Augment fwnode_get_named_gpiod() to configure the GPIO pin
   immediately after requesting it like all other APIs do.
   This is a treewide change also updating all users.
 
 - Pass a GPIO label down to gpiod_request() from
   fwnode_get_named_gpiod(). This makes debugfs and the userspace
   ABI correctly reflect the current in-kernel consumer of a pin
   taken using this abstraction. This is a treewide change also
   updating all users.
 
 - Rename devm_get_gpiod_from_child() to
   devm_fwnode_get_gpiod_from_child() to reflect the fact that this
   function is operating on a fwnode object. This is a treewide
   change also updating all users.
 
 - Make it possible to take multiple GPIOs in a single hog of device
   tree hogs.
 
 - The refactorings switching GPIO chips to use the .set_config()
   callback using standard pin control properties and providing
   a backend into the pin control subsystem that were also merged
   into the pin control tree naturally appear here too.
 
 Testing instrumentation:
 
 - A whole slew of cleanups and improvements to the mockup GPIO
   driver. We now have an extended userspace test exercising the
   subsystem, and we can inject interrupts etc from userspace
   to fully test the core GPIO functionality.
 
 New drivers:
 
 - New driver for the Cortina Systems Gemini GPIO controller.
 
 - New driver for the Exar XR17V352/354/358 chips.
 
 - New driver for the ACCES PCI-IDIO-16 PCI GPIO card.
 
 Driver changes:
 
 - RCAR: set the irqchip parent device, add fine-grained runtime
   PM support.
 
 - pca953x: support optional RESET control line on the chip.
 
 - DaVinci: cleanups and simplifications. Add support for multiple
   instances.
 
 - .set_multiple() and naming of lines on more or less all of the
   ISA/PCI GPIO controllers.
 
 - mcp23s08: refactored to use regmap as a first step to further
   rewrites and modernizations.
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Merge tag 'gpio-v4.11-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio

Pull GPIO updates from Linus Walleij:
 "This is the bulk of GPIO changes for the v4.11 cycle

  Core changes:

   - Augment fwnode_get_named_gpiod() to configure the GPIO pin
     immediately after requesting it like all other APIs do. This is a
     treewide change also updating all users.

   - Pass a GPIO label down to gpiod_request() from
     fwnode_get_named_gpiod(). This makes debugfs and the userspace ABI
     correctly reflect the current in-kernel consumer of a pin taken
     using this abstraction. This is a treewide change also updating all
     users.

   - Rename devm_get_gpiod_from_child() to
     devm_fwnode_get_gpiod_from_child() to reflect the fact that this
     function is operating on a fwnode object. This is a treewide change
     also updating all users.

   - Make it possible to take multiple GPIOs in a single hog of device
     tree hogs.

   - The refactorings switching GPIO chips to use the .set_config()
     callback using standard pin control properties and providing a
     backend into the pin control subsystem that were also merged into
     the pin control tree naturally appear here too.

  Testing instrumentation:

   - A whole slew of cleanups and improvements to the mockup GPIO
     driver. We now have an extended userspace test exercising the
     subsystem, and we can inject interrupts etc from userspace to fully
     test the core GPIO functionality.

  New drivers:

   - New driver for the Cortina Systems Gemini GPIO controller.

   - New driver for the Exar XR17V352/354/358 chips.

   - New driver for the ACCES PCI-IDIO-16 PCI GPIO card.

  Driver changes:

   - RCAR: set the irqchip parent device, add fine-grained runtime PM
     support.

   - pca953x: support optional RESET control line on the chip.

   - DaVinci: cleanups and simplifications. Add support for multiple
     instances.

   - .set_multiple() and naming of lines on more or less all of the
     ISA/PCI GPIO controllers.

   - mcp23s08: refactored to use regmap as a first step to further
     rewrites and modernizations"

* tag 'gpio-v4.11-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (61 commits)
  gpio: reintroduce devm_get_gpiod_from_child()
  gpio: pci-idio-16: Fix PCI BAR index
  gpio: pci-idio-16: Fix PCI device ID code
  gpio: mockup: implement event injecting over debugfs
  gpio: mockup: add a dummy irqchip
  gpio: mockup: implement naming the lines
  gpio: mockup: code shrink
  gpio: mockup: readability tweaks
  gpio: Add GPIO support for the ACCES PCI-IDIO-16
  gpio: Add the devm_fwnode_get_index_gpiod_from_child() helper
  gpio: Rename devm_get_gpiod_from_child()
  gpio: mcp23s08: Select REGMAP/REGMAP_I2C to fix build error
  gpio: ws16c48: Add support for GPIO names
  gpio: gpio-mm: Add support for GPIO names
  gpio: 104-idio-16: Add support for GPIO names
  gpio: 104-idi-48: Add support for GPIO names
  gpio: 104-dio-48e: Add support for GPIO names
  gpio: ws16c48: Remove unnecessary driver_data set
  gpio: gpio-mm: Remove unnecessary driver_data set
  gpio: 104-idio-16: Remove unnecessary driver_data set
  ...
2017-02-23 08:46:04 -08:00
Linus Walleij
e4df1ebdfe Merge branch 'ib-gpiod-flags' into devel 2017-02-05 23:14:23 +01:00
Boris Brezillon
537b94dafc gpio: Add the devm_fwnode_get_index_gpiod_from_child() helper
devm_fwnode_get_gpiod_from_child() currently allows GPIO users to
request a GPIO that is defined in a child fwnode instead of directly in
the device fwnode.
Extend this API by adding the devm_fwnode_get_index_gpiod_from_child()
helper which does the same except you can also specify an index in case
the 'xx-gpios' property describe several GPIOs.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-02-04 21:28:51 +01:00
Christophe JAILLET
3988d663c0 gpiolib: Fix a WARN_ON that can never trigger
"if (!x) WARN_ON(x)" can never trigger.

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-01-31 15:44:16 +01:00
Linus Walleij
7f36f5d11c Linux 4.10-rc6
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Merge tag 'v4.10-rc6' into devel

Linux 4.10-rc6

Resolved conflicts in:
	drivers/pinctrl/pinctrl-amd.c
	drivers/pinctrl/samsung/pinctrl-exynos.c
2017-01-30 14:39:20 +01:00
Linus Walleij
283a981387 Merge branch 'ib-pinctrl-genprops' of /home/linus/linux-pinctrl into devel 2017-01-26 15:28:02 +01:00
Mika Westerberg
2956b5d94a pinctrl / gpio: Introduce .set_config() callback for GPIO chips
Currently we already have two pin configuration related callbacks
available for GPIO chips .set_single_ended() and .set_debounce(). In
future we expect to have even more, which does not scale well if we need
to add yet another callback to the GPIO chip structure for each possible
configuration parameter.

Better solution is to reuse what we already have available in the
generic pinconf.

To support this, we introduce a new .set_config() callback for GPIO
chips. The callback takes a single packed pin configuration value as
parameter. This can then be extended easily beyond what is currently
supported by just adding new types to the generic pinconf enum.

If the GPIO driver is backed up by a pinctrl driver the GPIO driver can
just assign gpiochip_generic_config() (introduced in this patch) to
.set_config and that will take care configuration requests are directed
to the pinctrl driver.

We then convert the existing drivers over .set_config() and finally
remove the .set_single_ended() and .set_debounce() callbacks.

Suggested-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-01-26 15:27:37 +01:00
Linus Walleij
8c541b1148 Merge branch 'ib-gpiod-flags' into devel 2017-01-26 10:00:31 +01:00
Alexander Stein
b2987d7438 gpio: Pass GPIO label down to gpiod_request
Currently all users of fwnode_get_named_gpiod() have no way to
specify a label for the GPIO. So GPIOs listed in debugfs are shown
with label "?". With this change a proper label is used.

Also adjust all users so they can pass a label, properly retrieved
from device tree properties.

Signed-off-by: Alexander Stein <alexander.stein@systec-electronic.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Jacek Anaszewski <jacek.anaszewski@gmail.com>
Acked-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-01-26 09:59:52 +01:00
Andy Shevchenko
a264d10ff4 gpiolib: Convert fwnode_get_named_gpiod() to configure GPIO
Make fwnode_get_named_gpiod() consistent with the rest of
gpiod_get() like API, i.e. configure GPIO pin immediately after
request.

Besides obvious clean up it will help to configure pins based
on firmware provided resources.

Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-01-26 09:59:32 +01:00
Linus Walleij
739e6f5945 gpio: provide lockdep keys for nested/unnested irqchips
The helper function for adding a GPIO chip compiles in a lockdep
key for debugging, the same key is needed for nested chips as
well.

The macro construction is unreadable, replace this with two
static inlines instead.

The _gpiochip_irqchip_add prefixed function is not helpful,
rename it with gpiochip_irqchip_add_key() that tell us what the
function is actually doing.

Fixes: d245b3f9bd ("gpio: simplify adding threaded interrupts")
Cc: Roger Quadros <rogerq@ti.com>
Reported-by: Clemens Gruber <clemens.gruber@pqgruber.com>
Reported-by: Roger Quadros <rogerq@ti.com>
Reported-by: Grygorii Strashko <grygorii.strashko@ti.com>
Tested-by: Clemens Gruber <clemens.gruber@pqgruber.com>
Tested-by: Grygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-01-19 09:57:20 +01:00
Stephen Boyd
fb505747c0 gpio: Remove impossible checks on container_of() result
container_of() does pointer math on the pointer that's passed in.
If it were to return a NULL pointer the value passed in would
need to be perfectly offset from 0 to make that so. Remove these
checks because they don't make sense.

Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-01-11 16:01:27 +01:00
Andy Shevchenko
5e4e6fb3ff gpiolib: Switch to for_each_set_bit()
The macro for_each_set_bit() effectively looks up to the next
set bit in array of bits.

Instead of open coding that switch to for_each_set_bit() in
gpio_chip_set_multiple().

While here, make gpio_chip_set_multiple() non-destructive
against its parameters. We are safe since all callers, i.e.
gpiod_set_array_value_complex(), handle that already.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-01-11 12:07:17 +01:00
Geert Uytterhoeven
5018ada69a gpio: Move freeing of GPIO hogs before numbing of the device
When removing a gpiochip that uses GPIO hogging (e.g. by unloading the
chip's DT overlay), a warning is printed:

    gpio gpiochip8: REMOVING GPIOCHIP WITH GPIOS STILL REQUESTED

This happens because gpiochip_free_hogs() is called after the gdev->chip
pointer is reset to NULL. Hence __gpiod_free() cannot determine the
chip in use, and cannot clear flags nor call the optional chip-specific
.free() callback.

Move the call to gpiochip_free_hogs() up to fix this.

Cc: stable@vger.kernel.org
Fixes: ff2b135922 ("gpio: make the gpiochip a real device")
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-12-30 09:11:21 +01:00
Linus Torvalds
061ad5038c Bulk GPIO changes for the v4.10 kernel cycle:
Core changes:
 
 - Simplify threaded interrupt handling: instead of passing
   numbed parameters to gpiochip_irqchip_add_chained() we
   create a new call: gpiochip_irqchip_add_nested() so the two
   types are clearly semantically different. Also make sure
   that all nested chips call gpiochip_set_nested_irqchip()
   which is necessary for IRQ resend to work properly if
   it happens.
 
 - Return error on seek operations for the chardev.
 
 - Clamp values set as part of gpio[d]_direction_output() so
   that anything != 0 will be send down to the driver as "1"
   not the value passed in.
 
 - ACPI can now support naming of GPIO lines, hogs and holes
   in the GPIO lists.
 
 New drivers:
 
 - The SX150x driver was deemed unfit for the GPIO subsystem
   and was moved over to a combined GPIO+pinctrl driver in the
   pinctrl subsystem.
 
 New features:
 
 - Various cleanups to various drivers.
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Merge tag 'gpio-v4.10-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio

Pull GPIO updates from Luinus Walleij:
 "Bulk GPIO changes for the v4.10 kernel cycle:

  Core changes:

   - Simplify threaded interrupt handling: instead of passing numbed
     parameters to gpiochip_irqchip_add_chained() we create a new call:
     gpiochip_irqchip_add_nested() so the two types are clearly
     semantically different. Also make sure that all nested chips call
     gpiochip_set_nested_irqchip() which is necessary for IRQ resend to
     work properly if it happens.

   - Return error on seek operations for the chardev.

   - Clamp values set as part of gpio[d]_direction_output() so that
     anything != 0 will be send down to the driver as "1" not the value
     passed in.

   - ACPI can now support naming of GPIO lines, hogs and holes in the
     GPIO lists.

  New drivers:

   - The SX150x driver was deemed unfit for the GPIO subsystem and was
     moved over to a combined GPIO+pinctrl driver in the pinctrl
     subsystem.

  New features:

   - Various cleanups to various drivers"

* tag 'gpio-v4.10-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (49 commits)
  gpio: merrifield: Implement gpio_get_direction callback
  gpio: merrifield: Add support for hardware debouncer
  gpio: chardev: Return error for seek operations
  gpio: arizona: Tidy up probe error path
  gpio: arizona: Remove pointless set of platform drvdata
  gpio: pl061: delete platform data handling
  gpio: pl061: move platform data into driver
  gpio: pl061: rename variable from chip to pl061
  gpio: pl061: rename state container struct
  gpio: pl061: use local state for parent IRQ storage
  gpio: set explicit nesting on drivers
  gpio: simplify adding threaded interrupts
  gpio: vf610: use builtin_platform_driver
  gpio: axp209: use correct register for GPIO input status
  gpio: stmpe: fix interrupt handling bug
  gpio: em: depnd on ARCH_SHMOBILE
  gpio: zx: depend on ARCH_ZX
  gpio: x86: update config dependencies for x86 specific hardware
  gpio: mb86s7x: use builtin_platform_driver
  gpio: etraxfs: use builtin_platform_driver
  ...
2016-12-13 07:54:57 -08:00
Linus Walleij
acf1fcf772 Merge branch 'thread-irq-simpler' into devel 2016-12-07 15:24:12 +01:00
Lars-Peter Clausen
f4e81c5297 gpio: chardev: Return error for seek operations
The GPIO chardev is used for management tasks (allocating line and event
handles) and does neither support read() nor write() operations. Hence it
does not make much sense to allow seek operations.

Currently the chardev uses noop_llseek() for its seek implementation. This
function does not move the pointer and simply returns the current position
(always 0 for the GPIO chardev). noop_llseek() is primarily meant for
devices that can not support seek, but where there might be a user that
depends on the seek() operation succeeding. For newly added devices that
can not support seek operations it is recommended to use no_llseek(), which
will return an error. For more information see commit 6038f373a3
("llseek: automatically add .llseek fop").

Unfortunately this was overlooked when the GPIO chardev ABI was introduced.
But it is highly unlikely that since then userspace applications have
appeared that rely on being able to perform non-failing seek operations on
a GPIO chardev file descriptor. So it should be safe to change from
noop_llseel() to no_seek(). Also use nonseekable_open() in the chardev
open() callback to clear the FMODE_SEEK, FMODE_PREAD and FMODE_PWRITE flags
from the file. Neither of these should be set on a file that does not
support seek operations.

Cc: stable@vger.kernel.org
Fixes: 3c702e9987 ("gpio: add a userspace chardev ABI for GPIOs")
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-12-07 15:23:39 +01:00
Linus Walleij
d245b3f9bd gpio: simplify adding threaded interrupts
This tries to simplify the use of CONFIG_GPIOLIB_IRQCHIP when
using threaded interrupts: add a new call
gpiochip_irqchip_add_nested() to indicate that we're dealing
with a nested rather than a chained irqchip, then create a
separate gpiochip_set_nested_irqchip() to mirror
the gpiochip_set_chained_irqchip() call to connect the
parent and child interrupts.

In the nested case gpiochip_set_nested_irqchip() does nothing
more than call irq_set_parent() on each valid child interrupt,
which has little semantic effect in the kernel, but this is
probably still formally correct.

Update all drivers using nested interrupts to use
gpiochip_irqchip_add_nested() so we can now see clearly
which these users are.

The DLN2 driver can drop its specific hack with
.irq_not_threaded as we now recognize whether a chip is
threaded or not from its use of gpiochip_irqchip_add_nested()
signature rather than from inspecting .can_sleep.

We rename the .irq_parent to .irq_chained_parent since this
parent IRQ is only really kept around for the chained
interrupt handlers.

Cc: Lars Poeschel <poeschel@lemonage.de>
Cc: Octavian Purdila <octavian.purdila@intel.com>
Cc: Daniel Baluta <daniel.baluta@intel.com>
Cc: Bin Gao <bin.gao@linux.intel.com>
Cc: Mika Westerberg <mika.westerberg@linux.intel.com>
Cc: Ajay Thomas <ajay.thomas.david.rajamanickam@intel.com>
Cc: Semen Protsenko <semen.protsenko@globallogic.com>
Cc: Alexander Stein <alexander.stein@systec-electronic.com>
Cc: Phil Reid <preid@electromag.com.au>
Cc: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Cc: Patrice Chotard <patrice.chotard@st.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-11-25 15:12:27 +01:00
Linus Walleij
3940c34ac8 gpio: tag line labels used for interrupts
When a GPIO line is marked as used for an interrupt, it is
helpful to set the label to "interrupt" so we know what is
going on when inspecting the lines.

If a GPIO is already properly named by gpiod_get*() we don't
need to do this. It only happens when a line is used from
the irqchip side of a GPIO driver without communicating
with the GPIO side, such as when gpiochip is used as interrupt
provider in the device tree.

If the line is still marked as used by "interrupt" when we
unmark it as used by an interrupt, also remove this label
from the descriptor.

Also shape up the code around unmarking IRQ lines.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-11-15 10:30:08 +01:00
Linus Walleij
ad17731d7b gpio: clamp values on gpio[d]_direction_output()
I saw weird values != [0,1] being passed down to drivers
in their .set_direction_output() callbacks. Go over the
gpiolib and make sure to hammer it to [0,1] before hitting
the driver to avoid undesired side effects.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-11-15 10:29:41 +01:00
Linus Walleij
60f8339eb3 gpio: do not double-check direction on sleeping chips
When locking a GPIO line as IRQ, we go to lengths to
double-check that the line is really set as input before
marking it as used for IRQ. This is not good on GPIO chips
that can sleep, because this function is called in IRQ-safe
context. Just skip this if it can't be checked quickly.

Currently this happens on sleeping expanders such as STMPE
or TC3589x:

BUG: scheduling while atomic: swapper/1/0x00000002
Modules linked in:
CPU: 0 PID: 1 Comm: swapper Not tainted 4.9.0-rc1+ #38
Hardware name: Nomadik STn8815
[<c000f2e0>] (unwind_backtrace) from [<c000d244>] (show_stack+0x10/0x14)
[<c000d244>] (show_stack) from [<c0037b78>] (__schedule_bug+0x54/0x80)
[<c0037b78>] (__schedule_bug) from [<c042df14>] (__schedule+0x3a0/0x460)
[<c042df14>] (__schedule) from [<c042e028>] (schedule+0x54/0xb8)
(...)

This patch fixes that problem and relies on the direction
read from the chip when it was added.

Cc: stable@vger.kernel.org
Fixes: 9c10280d85 ("gpio: flush direction status in gpiochip_lock_as_irq()")
Cc: Patrice Chotard <patrice.chotard@st.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-11-15 10:26:34 +01:00
Lars-Peter Clausen
953b956a2e gpio: GPIO_GET_LINE{HANDLE,EVENT}_IOCTL: Fix file descriptor leak
When allocating a new line handle or event a file is allocated that it is
associated to. The file is attached to a file descriptor of the current
process and the file descriptor is returned to userspace using
copy_to_user(). If this copy operation fails the line handle or event
allocation is aborted, all acquired resources are freed and an error is
returned.

But the file struct is not freed and left attached to the userspace
application and even though the file descriptor number was not copied it is
trivial to guess. If a userspace application performs a IOCTL on such a
left over file descriptor it will trigger a use-after-free and if the file
descriptor is closed (latest when the application exits) a double-free is
triggered.

anon_inode_getfd() performs 3 tasks, allocate a file struct, allocate a
file descriptor for the current process and install the file struct in the
file descriptor. As soon as the file struct is installed in the file
descriptor it is accessible by userspace (even if the IOCTL itself hasn't
completed yet), this means uninstalling the fd on the error path is not an
option, since userspace might already got a reference to the file.

Instead anon_inode_getfd() needs to be broken into its individual steps.
The allocation of the file struct and file descriptor is done first, then
the copy_to_user() is executed and only if it succeeds the file is
installed.

Since the file struct is reference counted it can not be just freed, but
its reference needs to be dropped, which will also call the release()
callback, which will free the state attached to the file. So in this case
the normal error cleanup path should not be taken.

Cc: stable@vger.kernel.org
Fixes: d932cd4918 ("gpio: free handles in fringe cases")
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-10-31 21:23:44 +01:00
Lars-Peter Clausen
ac7dbb991e gpio: GPIO_GET_LINEEVENT_IOCTL: Reject invalid line and event flags
The GPIO_GET_LINEEVENT_IOCTL currently ignores unknown or undefined
linehandle and lineevent flags. From a backwards and forwards compatibility
viewpoint it is highly desirable to reject unknown flags though.

On one hand an application that is using newer flags and is running on
an older kernel has no way to detect if the new flags were handled
correctly if they are silently discarded.

On the other hand an application that (accidentally) passes undefined flags
will run fine on an older kernel, but may break on a newer kernel when
these flags get defined.

Ensure that requests that have undefined flags set are rejected with an
error, rather than silently discarding the undefined flags.

Cc: stable@vger.kernel.org
Fixes: 61f922db72 ("gpio: userspace ABI for reading GPIO line events")
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-10-21 14:48:56 +02:00
Lars-Peter Clausen
e3e847c7f1 gpio: GPIO_GET_LINEHANDLE_IOCTL: Reject invalid line flags
The GPIO_GET_LINEHANDLE_IOCTL currently ignores unknown or undefined
linehandle flags. From a backwards and forwards compatibility viewpoint it
is highly desirable to reject unknown flags though.

On one hand an application that is using newer flags and is running on
an older kernel has no way to detect if the new flags were handled
correctly if they are silently discarded.

On the other hand an application that (accidentally) passes undefined flags
will run fine on an older kernel, but may break on a newer kernel when
these flags get defined.

Ensure that requests that have undefined flags set are rejected with an
error, rather than silently discarding the undefined flags.

Cc: stable@vger.kernel.org
Fixes: d7c51b47ac ("gpio: userspace ABI for reading/writing GPIO lines")
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-10-21 14:47:44 +02:00
Lars-Peter Clausen
3eded5d83b gpio: GPIOHANDLE_GET_LINE_VALUES_IOCTL: Fix information leak
The GPIOHANDLE_GET_LINE_VALUES_IOCTL handler allocates a gpiohandle_data
struct on the stack and then passes it to copy_to_user(). But depending on
the number of requested line handles the struct is only partially
initialized.

This exposes the previous, potentially sensitive, stack content to the
issuing userspace application. To avoid this make sure that the struct is
fully initialized.

Cc: stable@vger.kernel.org
Fixes: d7c51b47ac ("gpio: userspace ABI for reading/writing GPIO lines")
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-10-21 14:46:28 +02:00
Lars-Peter Clausen
b8b0e3d303 gpio: GPIO_GET_LINEEVENT_IOCTL: Validate line offset
The line offset that is used as an index into the descs array is provided
by userspace and might go beyond the bounds of the array. If that happens
undefined behavior will occur.

Make sure that the offset is within the bounds of the desc array and reject
any requests that specify a value outside of it.

Cc: stable@vger.kernel.org
Fixes: 61f922db72 ("gpio: userspace ABI for reading GPIO line events")
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-10-21 14:41:38 +02:00