Commit Graph

412 Commits

Author SHA1 Message Date
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 a9a1d2a782 pinctrl/gpio: Unify namespace for cross-calls
The pinctrl_request_gpio() and pinctrl_free_gpio() break the nice
namespacing in the other cross-calls like pinctrl_gpio_foo().
Just rename them and all references so we have one namespace
with all cross-calls under pinctrl_gpio_*().

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-09-22 11:02:10 +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
Lars-Peter Clausen d82aa4a8f2 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 only the
first element of the values array in the struct is set, which leaves the
struct 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: 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 14:40:29 +02:00
Lars-Peter Clausen e405f9fcb6 gpio: GPIO_GET_LINEHANDLE_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: 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 14:39:18 +02:00
Lars-Peter Clausen 0f4bbb2337 gpio: GPIO_GET_CHIPINFO_IOCTL: Fix information leak
The GPIO_GET_CHIPINFO_IOCTL handler allocates a gpiochip_info struct on the
stack and then passes it to copy_to_user(). But depending on the length of
the GPIO chip name and label 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: 521a2ad6f8 ("gpio: add userspace ABI for GPIO line information")
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-10-21 14:38:02 +02:00
Lars-Peter Clausen 1f1cc4566b gpio: GPIO_GET_CHIPINFO_IOCTL: Fix line offset validation
The current line offset validation is off by one. Depending on the data
stored behind the descs array this can either cause undefined behavior or
disclose arbitrary, potentially sensitive, memory to the issuing userspace
application.

Make sure that offset is within the bounds of the desc array.

Cc: stable@vger.kernel.org
Fixes: 521a2ad6f8 ("gpio: add userspace ABI for GPIO line information")
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-10-21 14:36:44 +02:00
Linus Walleij 031ba28a81 gpio: acpi: separation of concerns
The generic GPIO library directly implement code for acpi_find_gpio()
which is only used with CONFIG_ACPI. This was probably done because
OF did the same thing, but I removed that so remove this too.

Rename the internal acpi_find_gpio() in gpiolib-acpi.c to
acpi_populate_gpio_lookup() which seems to be more appropriate anyway
so as to avoid a namespace clash with the same function.

Make the stub return -ENOENT rather than -ENOSYS (as that is for
syscalls!).

For some reason the sunxi pin control driver was including the private
gpiolib header, it works just fine without it so remove that oneliner.

Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-10-03 23:38:10 +02:00
Linus Walleij ea713bc450 gpio: OF: separation of concerns
The generic GPIO library directly implement code for of_find_gpio()
which is only used with CONFIG_OF and causes compilation problems
on archs that do not even have stubs for OF functions, especially
on UM that does not implement any IO remap functions.

Move the function to gpiolib-of.c, implement a static inline stub
in gpiolib.h returning PTR_ERR(-ENOENT) if CONFIG_OF_GPIO is not
set and be done with it.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-10-03 15:27:05 +02:00
Linus Walleij 22a5db98a3 Merge branch 'gpio-irq-validmask' of /home/linus/linux-pinctrl into devel 2016-09-23 14:51:18 +02:00
Mika Westerberg 79b804cb6a gpiolib: Make it possible to exclude GPIOs from IRQ domain
When using GPIO irqchip helpers to setup irqchip for a gpiolib based
driver, it is not possible to select which GPIOs to add to the IRQ domain.
Instead it just adds all GPIOs which is not always desired. For example
there might be GPIOs that for some reason cannot generated normal
interrupts at all.

To support this we add a flag irq_need_valid_mask to struct gpio_chip. When
this flag is set the core allocates irq_valid_mask that holds one bit for
each GPIO the chip has. By default all bits are set but drivers can
manipulate this using set_bit() and clear_bit() accordingly.

Then when gpiochip_irqchip_add() is called, this mask is checked and all
GPIOs with bit is set are added to the IRQ domain created for the GPIO
chip.

Suggested-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-09-23 14:49:50 +02:00
Mika Westerberg 0a1e005374 gpiolib: Forbid irqchip default trigger for ACPI enumerated devices
Follow DT and forbid default trigger if the GPIO irqchip device is
enumerated from ACPI. Triggering for these devices will be configured
automatically from ACPI interrupt resources provided by the BIOS.

Suggested-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-09-13 10:45:59 +02:00
Marc Zyngier 332e99d5ae gpio/gpiolib: Forbid irqchip default trigger if probed over DT
Using a default trigger is a bad idea if using DT to configure
interrupts, as the device's interrupt specifier will always contain
the trigger configuration.

Let's warn about that particular situation, and revert to not
having a default. Hopefully, the couple of drivers still using
this feature will quickly be fixed.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-09-12 11:05:03 +02:00
Masahiro Yamada acf06ff76c gpio: refactor gpiochip_find() slightly
The if...else... block after the loop can be dropped with
a slight refactoring.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-08-19 10:55:08 +02:00
Linus Torvalds 1cd04d293c This is the bulk of GPIO changes for the v4.8 kernel cycle.
Core changes:
 
 - The big item is of course the completion of the character
   device ABI. It has now replaced and surpassed the former
   unmaintainable sysfs ABI: we can now hammer (bitbang)
   individual lines or sets of lines and read individual lines
   or sets of lines from userspace, and we can also register
   to listen to GPIO events from userspace. As a tie-in we
   have two new tools in tools/gpio: gpio-hammer and
   gpio-event-mon that illustrate the proper use of the new
   ABI. As someone said: the wild west days of GPIO are now
   over.
 
 - Continued to remove the pointless
   ARCH_[WANT_OPTIONAL|REQUIRE]_GPIOLIB Kconfig symbols.
   I'm patching hexagon, openrisc, powerpc, sh, unicore,
   ia64 and microblaze. These are either ACKed by their
   maintainers or patched anyways after a grace period and
   no response from maintainers. Some archs (ARM) come in from
   their trees, and others (x86) are still not fixed, so I
   might send a second pull request to root it out later in
   this merge window, or just defer to v4.9.
 
 - The GPIO tools are moved to the tools build system.
 
 New drivers:
 
 - New driver for the MAX77620/MAX20024.
 
 - New driver for the Intel Merrifield.
 
 - Enabled PCA953x for the TI PCA9536.
 
 - Enabled PCA953x for the Intel Edison.
 
 - Enabled R8A7792 in the RCAR driver.
 
 Driver improvements:
 
 - The STMPE and F7188x now supports the .get_direction()
   callback.
 
 - The Xilinx driver supports setting multiple lines at
   once.
 
 - ACPI support for the Vulcan GPIO controller.
 
 - The MMIO GPIO driver supports device tree probing.
 
 - The Acer One 10 is supported through the _DEP ACPI
   attribute.
 
 Cleanups:
 
 - A major cleanup of the OF/DT support code. It is way
   easier to read and understand now, probably this improves
   performance too.
 
 - Drop a few redundant .owner assignments.
 
 - Remove CLPS711x boardfile support: we are 100% DT.
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Merge tag 'gpio-v4.8-1' 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 v4.8 kernel cycle.  The big
  news is the completion of the chardev ABI which I'm very happy about
  and apart from that it's an ordinary, quite busy cycle.  The details
  are below.

  The patches are tested in linux-next for some time, patches to other
  subsystem mostly have ACKs.

  I got overly ambitious with configureing lines as input for IRQ lines
  but it turns out that some controllers have their interrupt-enable and
  input-enabling in orthogonal settings so the assumption that all IRQ
  lines are input lines does not hold.  Oh well, revert and back to the
  drawing board with that.

  Core changes:

   - The big item is of course the completion of the character device
     ABI.  It has now replaced and surpassed the former unmaintainable
     sysfs ABI: we can now hammer (bitbang) individual lines or sets of
     lines and read individual lines or sets of lines from userspace,
     and we can also register to listen to GPIO events from userspace.

     As a tie-in we have two new tools in tools/gpio: gpio-hammer and
     gpio-event-mon that illustrate the proper use of the new ABI.  As
     someone said: the wild west days of GPIO are now over.

   - Continued to remove the pointless ARCH_[WANT_OPTIONAL|REQUIRE]_GPIOLIB
     Kconfig symbols.  I'm patching hexagon, openrisc, powerpc, sh,
     unicore, ia64 and microblaze.  These are either ACKed by their
     maintainers or patched anyways after a grace period and no response
     from maintainers.

     Some archs (ARM) come in from their trees, and others (x86) are
     still not fixed, so I might send a second pull request to root it
     out later in this merge window, or just defer to v4.9.

   - The GPIO tools are moved to the tools build system.

  New drivers:

   - New driver for the MAX77620/MAX20024.

   - New driver for the Intel Merrifield.

   - Enabled PCA953x for the TI PCA9536.

   - Enabled PCA953x for the Intel Edison.

   - Enabled R8A7792 in the RCAR driver.

  Driver improvements:

   - The STMPE and F7188x now supports the .get_direction() callback.

   - The Xilinx driver supports setting multiple lines at once.

   - ACPI support for the Vulcan GPIO controller.

   - The MMIO GPIO driver supports device tree probing.

   - The Acer One 10 is supported through the _DEP ACPI attribute.

  Cleanups:

   - A major cleanup of the OF/DT support code.  It is way easier to
     read and understand now, probably this improves performance too.

   - Drop a few redundant .owner assignments.

   - Remove CLPS711x boardfile support: we are 100% DT"

* tag 'gpio-v4.8-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (67 commits)
  MAINTAINERS: Add INTEL MERRIFIELD GPIO entry
  gpio: dwapb: add missing fwnode_handle_put() in dwapb_gpio_get_pdata()
  gpio: merrifield: Protect irq_ack() and gpio_set() by lock
  gpio: merrifield: Introduce GPIO driver to support Merrifield
  gpio: intel-mid: Make it depend to X86_INTEL_MID
  gpio: intel-mid: Sort header block alphabetically
  gpio: intel-mid: Remove potentially harmful code
  gpio: rcar: add R8A7792 support
  gpiolib: remove duplicated include from gpiolib.c
  Revert "gpio: convince line to become input in irq helper"
  gpiolib: of_find_gpio(): Don't discard errors
  gpio: of: Allow overriding the device node
  gpio: free handles in fringe cases
  gpio: tps65218: Add platform_device_id table
  gpio: max77620: get gpio value based on direction
  gpio: lynxpoint: avoid potential warning on error path
  tools/gpio: add install section
  tools/gpio: move to tools buildsystem
  gpio: intel-mid: switch to devm_gpiochip_add_data()
  gpio: 74x164: Use spi_write() helper instead of open coding
  ...
2016-07-26 19:16:01 -07:00
Wei Yongjun ee4fc4013e gpiolib: remove duplicated include from gpiolib.c
Remove duplicated include.

Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-07-22 15:30:39 +02:00
Linus Walleij 78456d6ff8 Revert "gpio: convince line to become input in irq helper"
This reverts commit 7e7c059cb5.

I was wrong about trying to do this, as it breaks the
orthogonality between gpiochips and irqchips.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-07-06 14:40:08 +02:00
Lars-Peter Clausen da17f8a113 gpiolib: of_find_gpio(): Don't discard errors
Since commit dd34c37aa3 ("gpio: of: Allow -gpio suffix for property
names") when requesting a GPIO from the devicetree gpiolib looks for
properties with both the '-gpio' and the '-gpios' suffix. This was
implemented by first searching for the property with the '-gpios' suffix
and if that yields an error try the '-gpio' suffix. This approach has the
issue that any error returned when looking for the '-gpios' suffix is
silently discarded.

Commit 06fc3b70f1 ("gpio: of: Fix handling for deferred probe for -gpio
suffix") partially addressed the issue by treating the EPROBE_DEFER error
as a special condition. This fixed the case when the property is specified,
but the GPIO provider is not ready yet. But there are other cases in which
of_get_named_gpiod_flags() returns an error even though the property is
specified, e.g. if the specification is incorrect.

of_find_gpio() should only try to look for the property with the '-gpio'
suffix if no property with the '-gpios' suffix was found. If the property
was not found of_get_named_gpiod_flags() will return -ENOENT, so update the
condition to abort and propagate the error to the caller in all other
cases.

This is important for gpiod_get_optinal() and friends to behave correctly
in case the specifier contains errors. Without this patch they'll return
NULL if the property uses the '-gpios' suffix and the specifier contains
errors, which falsely indicates to the caller that no GPIO was specified.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-07-06 14:39:50 +02:00
Thierry Reding acc6e331b6 gpio: of: Allow overriding the device node
When registering a GPIO chip, drivers can override the device tree node
associated with the chip by setting the chip's ->of_node field. If set,
this field is supposed to take precedence over the ->parent->of_node
field, but the code doesn't actually do that.

Commit 762c2e46c0 ("gpio: of: remove of_gpiochip_and_xlate() and
struct gg_data") exposes this because it now no longer matches on the
GPIO chip's ->of_node field, but the GPIO device's ->of_node field that
is set using the procedure described above.

Signed-off-by: Thierry Reding <treding@nvidia.com>
Acked-by: Alexandre Courbot <acourbot@nvidia.com>
Reviewed-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-07-06 14:39:50 +02:00
Linus Walleij d932cd4918 gpio: free handles in fringe cases
If we fail when copying the ioctl() struct to userspace we still
need to clean up the cruft otherwise left behind or it will stay
around until the issuing process terminates the file handle.

Reported-by: Alexander Stein <alexander.stein@systec-electronic.com>
Acked-by: Alexander Stein <alexander.stein@systec-electronic.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-07-04 16:54:36 +02:00
Johan Hovold 85b03b3033 Revert "gpiolib: Split GPIO flags parsing and GPIO configuration"
This reverts commit 923b93e451.

Make sure consumers do not overwrite gpio flags for pins that have
already been claimed.

While adding support for gpio drivers to refuse a request using
unsupported flags, the order of when the requested flag was checked and
the new flags were applied was reversed to that consumers could
overwrite flags for already requested gpios.

This not only affects device-tree setups where two drivers could request
the same gpio using conflicting configurations, but also allowed user
space to clear gpio flags for already claimed pins simply by attempting
to export them through the sysfs interface. By for example clearing the
FLAG_ACTIVE_LOW flag this way, user space could effectively change the
polarity of a signal.

Reverting this change obviously prevents gpio drivers from doing sanity
checks on the flags in their request callbacks. Fortunately only one
recently added driver (gpio-tps65218 in v4.6) appears to do this, and a
follow up patch could restore this functionality through a different
interface.

Cc: stable <stable@vger.kernel.org>	# 4.4
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-07-04 16:51:29 +02:00
Linus Walleij 7e7c059cb5 gpio: convince line to become input in irq helper
The generic IRQ helper library just checks if the IRQ line is
set as input before activating it for interrupts. As we
recently started to check things better with .get_dir() it
turns out that it's good to try to convince the line to become
an input before attempting to lock it as IRQ.

Reviewed-by: Björn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-06-23 11:06:58 +02:00
Ben Dooks 33265b17e0 gpiolib: make lineevent_irq_thread static
The lineevent_irq_thread is not exported, so make it static
to fix the following warning:

drivers/gpio/gpiolib.c:654:13: warning: symbol 'lineevent_irq_thread' was not declared. Should it be static?

Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-06-18 11:04:56 +02:00
Linus Walleij e2f608be64 gpio: make the iterator point to last handle
When initializing the GPIO handles, we use the iterator (i)
to back off if something goes wrong. But since the iterator
is also used after we pass the loop, we must decrement by
one after exiting the loop so that we point at the last
element in the array.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Walter Harms <wharms@bfs.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-06-18 10:56:43 +02:00
Linus Walleij bfbbe44daf gpio: make library immune to error pointers
Most functions that take a GPIO descriptor in need to check the
descriptor for IS_ERR(). We do this mostly in the VALIDATE_DESC()
macro except for the gpiod_to_irq() function which needs special
handling.

Cc: stable@vger.kernel.org
Reported-by: Grygorii Strashko <grygorii.strashko@ti.com>
Reviewed-by: Grygorii Strashko <grygorii.strashko@ti.com>
Acked-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-06-17 18:12:19 +02:00
Linus Walleij 79bb71bd1d gpio: make sure gpiod_to_irq() returns negative on NULL desc
commit 54d77198fd
("gpio: bail out silently on NULL descriptors")
doesn't work for gpiod_to_irq(): drivers assume that NULL
descriptors will give negative IRQ numbers in return.

It has been pointed out that returning 0 is NO_IRQ and that
drivers should be amended to treat this as an error, but that
is for the longer term: now let us repair the semantics.

Cc: Maxime Ripard <maxime.ripard@free-electrons.com>
Reported-by: Hans de Goede <hdegoede@redhat.com>
Tested-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-06-17 18:12:07 +02:00
Arnd Bergmann bc0207a546 gpiolib: avoid uninitialized data in gpio kfifo
gcc reports a theoretical case for returning uninitialized data in
the kfifo when a GPIO interrupt happens and neither
GPIOEVENT_REQUEST_RISING_EDGE nor GPIOEVENT_REQUEST_FALLING_EDGE
are set:

drivers/gpio/gpiolib.c: In function 'lineevent_irq_thread':
drivers/gpio/gpiolib.c:683:87: error: 'ge.id' may be used uninitialized in this function [-Werror=maybe-uninitialized]

This case should not happen, but to be on the safe side, let's
return from the irq handler without adding data to the FIFO
to ensure we can never leak stack data to user space.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Fixes: 61f922db72 ("gpio: userspace ABI for reading GPIO line events")
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-06-16 12:00:25 +02:00
Linus Walleij 61f922db72 gpio: userspace ABI for reading GPIO line events
This adds an ABI for listening to events on GPIO lines.
The mechanism returns an anonymous file handle to a request
to listen to a specific offset on a specific gpiochip.
To fetch the stream of events from the file handle, userspace
simply reads an event.

- Events can be requested with the same flags as ordinary
  handles, i.e. open drain or open source. An ioctl() call
  GPIO_GET_LINEEVENT_IOCTL is issued indicating the desired
  line.

- Events can be requested for falling edge events, rising
  edge events, or both.

- All events are timestamped using the kernel real time
  nanosecond timestamp (the same as is used by IIO).

- The supplied consumer label will appear in "lsgpio"
  listings of the lines, and in /proc/interrupts as the
  mechanism will request an interrupt from the gpio chip.

- Events are not supported on gpiochips that do not serve
  interrupts (no legal .to_irq() call). The event interrupt
  is threaded to avoid any realtime problems.

- It is possible to also directly read the current value
  of the registered GPIO line by issuing the same
  GPIOHANDLE_GET_LINE_VALUES_IOCTL as used by the
  line handles. Setting the value is not supported: we
  do not listen to events on output lines.

This ABI is strongly influenced by Industrial I/O and surpasses
the old sysfs ABI by providing proper precision timestamps,
making it possible to set flags like open drain, and put
consumer names on the GPIO lines.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-06-15 09:29:17 +02:00
Linus Walleij d7c51b47ac gpio: userspace ABI for reading/writing GPIO lines
This adds a userspace ABI for reading and writing GPIO lines.
The mechanism returns an anonymous file handle to a request
to read/write n offsets from a gpiochip. This file handle
in turn accepts two ioctl()s: one that reads and one that
writes values to the selected lines.

- Handles can be requested as input/output, active low,
  open drain, open source, however when you issue a request
  for n lines with GPIO_GET_LINEHANDLE_IOCTL, they must all
  have the same flags, i.e. all inputs or all outputs, all
  open drain etc. If a granular control of the flags for
  each line is desired, they need to be requested
  individually, not in a batch.

- The GPIOHANDLE_GET_LINE_VALUES_IOCTL read ioctl() can be
  issued also to output lines to verify that the hardware
  is in the expected state.

- It reads and writes up to GPIOHANDLES_MAX lines at once,
  utilizing the .set_multiple() call in the driver if
  possible, making the call efficient if several lines
  can be written with a single register update.

The limitation of GPIOHANDLES_MAX to 64 lines is done under
the assumption that we may expect hardware that can issue a
transaction updating 64 bits at an instant but unlikely
anything larger than that.

ChangeLog v2->v3:
- Use gpiod_get_value_cansleep() so we support also slowpath
  GPIO drivers.
- Fix up the UAPI docs kerneldoc.
- Allocate the anonymous fd last, so that the release
  function don't get called until that point of something
  fails. After this point, skip the errorpath.
ChangeLog v1->v2:
- Handle ioctl_compat() properly based on a similar patch
  to the other ioctl() handling code.
- Use _IOWR() as we pass pointers both in and out of the
  ioctl()
- Use kmalloc() and kfree() for the linehandled, do not
  try to be fancy with devm_* it doesn't work the way I
  thought.
- Fix const-correctness on the linehandle name field.

Acked-by: Michael Welling <mwelling@ieee.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-06-15 09:28:50 +02:00
Ricardo Ribalda Delgado f4833b8cc7 gpiolib: Fix unaligned used of reference counters
gpiolib relies on the reference counters to clean up the gpio_device
structure.

Although the number of get/put is properly aligned on gpiolib.c
itself, it does not take into consideration how the referece counters
are affected by other external functions such as cdev_add and device_add.

Because of this, after the last call to put_device, the reference counter
has a value of +3, therefore never calling gpiodevice_release.

Due to the fact that some of the device  has already been cleaned on
gpiochip_remove, the library will end up OOPsing the kernel (e.g. a call
to of_gpiochip_find_and_xlate).

Cc: stable@vger.kernel.org
Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-06-08 10:40:29 +02:00
Ricardo Ribalda Delgado 11f33a6d15 gpiolib: Fix NULL pointer deference
Under some circumstances, a gpiochip might be half cleaned from the
gpio_device list.

This patch makes sure that the chip pointer is still valid, before
calling the match function.

[  104.088296] BUG: unable to handle kernel NULL pointer dereference at
0000000000000090
[  104.089772] IP: [<ffffffff813d2045>] of_gpiochip_find_and_xlate+0x15/0x80
[  104.128273] Call Trace:
[  104.129802]  [<ffffffff813d2030>] ? of_parse_own_gpio+0x1f0/0x1f0
[  104.131353]  [<ffffffff813cd910>] gpiochip_find+0x60/0x90
[  104.132868]  [<ffffffff813d21ba>] of_get_named_gpiod_flags+0x9a/0x120
...
[  104.141586]  [<ffffffff8163d12b>] gpio_led_probe+0x11b/0x360

Cc: stable@vger.kernel.org
Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-06-08 10:38:03 +02:00
Linus Walleij 545ebd9a9b gpio: drop lock before reading GPIO direction
When adding the gpiochip, the GPIO HW drivers' callback get_direction()
could get called in atomic context. Some of the GPIO HW drivers may
sleep when accessing the register.

Move the lock before initializing the descriptors.

Reported-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-05-30 17:11:59 +02:00
Linus Walleij 54d77198fd gpio: bail out silently on NULL descriptors
In fdeb8e1547
("gpio: reflect base and ngpio into gpio_device")
assumed that GPIO descriptors are either valid or error
pointers, but gpiod_get_[index_]optional() actually return
NULL descriptors and then all subsequent calls should just
bail out.

Cc: stable@vger.kernel.org
Cc: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: Andrew Lunn <andrew@lunn.ch>
Fixes: fdeb8e1547 ("gpio: reflect base and ngpio into gpio_device")
Reported-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-05-30 16:56:41 +02:00
Linus Walleij 8b92e17efe gpio: handle compatible ioctl() pointers
If we're using the compatible ioctl() we need to handle the
argument pointer in a special way or there will be trouble.

Fixes: 3c702e9987 ("gpio: add a userspace chardev ABI for GPIOs")
Reported-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Reviewed-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-05-30 16:00:31 +02:00
Linus Walleij 9c10280d85 gpio: flush direction status in gpiochip_lock_as_irq()
As irqchip and gpiochip functions are orthogonal, the IRQ
set-up or something else can have changed the direction of
the GPIO line from what the GPIO descriptor knows when we
get into gpiochip_lock_as_irq(). Make sure to re-read the
direction setting if we have the .get_direction() callback
enabled for the chip.

Else we get problems like this:

iio iio:device2: interrupts on the rising edge
gpio gpiochip2: (8012e080.gpio): gpiochip_lock_as_irq:
  tried to flag a GPIO set as output for IRQ
gpio gpiochip2: (8012e080.gpio): unable to lock HW IRQ 0 for IRQ
genirq: Failed to request resources for l3g4200d-trigger
  (irq 111) on irqchip nmk1-32-63
iio iio:device2: failed to request trigger IRQ.
st-gyro-i2c: probe of 2-0068 failed with error -22

Fixes: 72d3200061 ("gpio: set up initial state from .get_direction()")
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-05-30 09:42:03 +02:00
Linus Torvalds 1eccc6e152 This is the bulk of GPIO changes for kernel cycle v4.7:
Core infrastructural changes:
 
 - Support for natively single-ended GPIO driver stages. This
   means that if the hardware has registers to configure open
   drain or open source configuration, we use that rather than
   (as we did before) try to emulate it by switching the line
   to an input to get high impedance. This is also documented
   throughly in Documentation/gpio/driver.txt for those of you
   who did not understand one word of what I just wrote.
 
 - Start to do away with the unnecessarily complex and
   unitelligible ARCH_REQUIRE_GPIOLIB and
   ARCH_WANT_OPTIONAL_GPIOLIB, another evolutional artifact from
   the time when the GPIO subsystem was unmaintained. Archs can
   now just select GPIOLIB and be done with it, cleanups to
   arches will trickle in for the next kernel. Some minor archs
   ACKed the changes immediately so these are included in this
   pull request.
 
 - Advancing the use of the data pointer inside the GPIO device
   for storing driver data by switching the PowerPC, Super-H
   Unicore and a few other subarches or subsystem drivers in
   ALSA SoC, Input, serial, SSB, staging etc to use it.
 
 - The initialization now reads the input/output state of the
   GPIO lines, so that each GPIO descriptor knows - if this
   callback is implemented - whether the line is input or
   output. This also reflects nicely in userspace "lsgpio".
 
 - It is now possible to name GPIO producer names, line names,
   from the device tree. (Platform data has been supported for
   a while.) I bet we will get a similar mechanism for ACPI
   one of those days. This makes is possible to get sensible
   producer names for e.g. GPIO rails in "lsgpio" in userspace.
 
 New drivers:
 
 - New driver for the Loongson1.
 
 - The XLP driver now supports Broadcom Vulcan ARM64.
 
 - The IT87 driver now supports IT8620 and IT8628.
 
 - The PCA953X driver now supports Galileo Gen2.
 
 Driver improvements:
 
 - MCP23S08 was switched to use the gpiolib irqchip helpers and
   now also suppors level-triggered interrupts.
 
 - 74x164 and RCAR now supports the .set_multiple() callback
 
 - AMDPT was converted to use generic GPIO.
 
 - TC3589x, TPS65218, SX150X, F7188X, MENZ127, VX855, WM831X, WM8994
   support the new single ended callback for open drain
   and in some cases open source.
 
 - Implement the .get_direction() callback for a few more drivers
   like PL061, Xgene.
 
 Cleanups:
 
 - Paul Gortmaker combed through the drivers and de-modularized
   those who are not really modules.
 
 - Move the GPIO poweroff DT bindings to the power subdir where
   they belong.
 
 - Rename gpio-generic.c to gpio-mmio.c, which is much more to the
   point. That's what it is handling, nothing more, nothing less.
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Merge tag 'gpio-v4.7-1' 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 kernel cycle v4.7:

  Core infrastructural changes:

   - Support for natively single-ended GPIO driver stages.

     This means that if the hardware has registers to configure open
     drain or open source configuration, we use that rather than (as we
     did before) try to emulate it by switching the line to an input to
     get high impedance.

     This is also documented throughly in Documentation/gpio/driver.txt
     for those of you who did not understand one word of what I just
     wrote.

   - Start to do away with the unnecessarily complex and unitelligible
     ARCH_REQUIRE_GPIOLIB and ARCH_WANT_OPTIONAL_GPIOLIB, another
     evolutional artifact from the time when the GPIO subsystem was
     unmaintained.

     Archs can now just select GPIOLIB and be done with it, cleanups to
     arches will trickle in for the next kernel.  Some minor archs ACKed
     the changes immediately so these are included in this pull request.

   - Advancing the use of the data pointer inside the GPIO device for
     storing driver data by switching the PowerPC, Super-H Unicore and
     a few other subarches or subsystem drivers in ALSA SoC, Input,
     serial, SSB, staging etc to use it.

   - The initialization now reads the input/output state of the GPIO
     lines, so that each GPIO descriptor knows - if this callback is
     implemented - whether the line is input or output.  This also
     reflects nicely in userspace "lsgpio".

   - It is now possible to name GPIO producer names, line names, from
     the device tree.  (Platform data has been supported for a while).
     I bet we will get a similar mechanism for ACPI one of those days.
     This makes is possible to get sensible producer names for e.g.
     GPIO rails in "lsgpio" in userspace.

  New drivers:

   - New driver for the Loongson1.

   - The XLP driver now supports Broadcom Vulcan ARM64.

   - The IT87 driver now supports IT8620 and IT8628.

   - The PCA953X driver now supports Galileo Gen2.

  Driver improvements:

   - MCP23S08 was switched to use the gpiolib irqchip helpers and now
     also suppors level-triggered interrupts.

   - 74x164 and RCAR now supports the .set_multiple() callback

   - AMDPT was converted to use generic GPIO.

   - TC3589x, TPS65218, SX150X, F7188X, MENZ127, VX855, WM831X, WM8994
     support the new single ended callback for open drain and in some
     cases open source.

   - Implement the .get_direction() callback for a few more drivers like
     PL061, Xgene.

  Cleanups:

   - Paul Gortmaker combed through the drivers and de-modularized those
     who are not really modules.

   - Move the GPIO poweroff DT bindings to the power subdir where they
     belong.

   - Rename gpio-generic.c to gpio-mmio.c, which is much more to the
     point.  That's what it is handling, nothing more, nothing less"

* tag 'gpio-v4.7-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (126 commits)
  MIPS: do away with ARCH_[WANT_OPTIONAL|REQUIRE]_GPIOLIB
  gpio: zevio: make it explicitly non-modular
  gpio: timberdale: make it explicitly non-modular
  gpio: stmpe: make it explicitly non-modular
  gpio: sodaville: make it explicitly non-modular
  pinctrl: sh-pfc: Let gpio_chip.to_irq() return zero on error
  gpio: dwapb: Add ACPI device ID for DWAPB GPIO controller on X-Gene platforms
  gpio: dt-bindings: add wd,mbl-gpio bindings
  gpio: of: make it possible to name GPIO lines
  gpio: make gpiod_to_irq() return negative for NO_IRQ
  gpio: xgene: implement .get_direction()
  gpio: xgene: Enable ACPI support for X-Gene GFC GPIO driver
  gpio: tegra: Implement gpio_get_direction callback
  gpio: set up initial state from .get_direction()
  gpio: rename gpio-generic.c into gpio-mmio.c
  gpio: generic: fix GPIO_GENERIC_PLATFORM is set to module case
  gpio: dwapb: add gpio-signaled acpi event support
  gpio: dwapb: convert device node to fwnode
  gpio: dwapb: remove name from dwapb_port_property
  gpio/qoriq: select IRQ_DOMAIN
  ...
2016-05-17 17:39:42 -07:00
Linus Walleij 4c37ce8608 gpio: make gpiod_to_irq() return negative for NO_IRQ
If a translation returns zero, that means NO_IRQ, so we
should return an error since the function is documented to
return a negative code on error.

Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-05-02 13:34:21 +02:00
Linus Walleij 72d3200061 gpio: set up initial state from .get_direction()
If the gpiochip supports the .get_direction() callback, then
the initial state of the descriptor flags should be set up
as output accordingly. Also put in comments explaining what is
going on.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-04-30 13:01:51 +02:00
Linus Walleij 44c7288f79 gpio: move gpiod_set_array_value_priv()
This renames gpiod_set_array_value_priv() to
gpiod_set_array_value_complex() and moves it to the gpiolib.h
private header file so we can reuse it in the subsystem.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-04-26 10:51:36 +02:00
Laxman Dewangan c31a571d43 gpio: gpiolib: Print error number if gpio hog failed
Print the error number of GPIO hog failed during its configurations.
This helps in identifying the failure without instrumenting the code.

Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-04-14 14:50:49 +02:00
Guenter Roeck 159f3cd92f gpiolib: Defer gpio device setup until after gpiolib initialization
Since commit ff2b135922 ("gpio: make the gpiochip a real device"),
attempts to add a gpio chip prior to gpiolib initialization cause
the system to crash. This happens because gpio_bus_type has not been
registered yet. Defer creating gpio devices until after gpiolib has
been initialized to fix the problem.

Cc: Greg Ungerer <gerg@uclinux.org>
Cc: Alexandre Courbot <gnurou@gmail.com>
Fixes: ff2b135922 ("gpio: make the gpiochip a real device")
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-04-08 10:10:09 +02:00
Guenter Roeck 476e2fc5cd gpiolib: Do not use devm functions when registering gpio chip
It is possible that a gpio chip is registered before the gpiolib
initialization code has run. This means we can not use devm_ functions
to allocate memory at that time. Do it the old fashioned way.

Cc: Alexandre Courbot <gnurou@gmail.com>
Cc: Greg Ungerer <gerg@uclinux.org>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-04-08 10:10:09 +02:00
Dmitry Torokhov 25487533ff gpio / ACPI: ignore GpioInt() GPIOs when requesting GPIO_OUT_*
When firmware does not use _DSD properties that allow properly name GPIO
resources, the kernel falls back on parsing _CRS resources, and will
return entries described as GpioInt() as general purpose GPIOs even
though they are meant to be used simply as interrupt sources for the
device:

Device (ETSA)
{
	Name (_HID, "ELAN0001")
	...

	Method(_CRS, 0x0, NotSerialized)
	{
		Name(BUF0,ResourceTemplate ()
		{
			I2CSerialBus(
				0x10,                     /* SlaveAddress */
				ControllerInitiated,      /* SlaveMode */
				400000,                   /* ConnectionSpeed */
				AddressingMode7Bit,       /* AddressingMode */
				"\\_SB.I2C1",             /* ResourceSource */
			)
			GpioInt (Edge, ActiveLow, ExclusiveAndWake, PullNone,,
				 "\\_SB.GPSW") { BOARD_TOUCH_GPIO_INDEX }
		} )
		Return (BUF0)
	}
...
}

This gives troubles with drivers such as Elan Touchscreen driver
(elants_i2c) that uses devm_gpiod_get to look up "reset" GPIO line and
decide whether the driver is responsible for powering up and resetting
the device, or firmware is. In the above case the lookup succeeds, we
map GPIO as output and later fail to request client->irq interrupt that
is mapped to the same GPIO.

Let's ignore resources described as GpioInt() while parsing _CRS when
requesting output GPIOs (but allow them when requesting GPIOD_ASIS or
GPIOD_IN as some drivers, such as i2c-hid, do request GPIO as input and
then map it to interrupt with gpiod_to_irq).

Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Dmitry Torokhov <dtor@chromium.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-04-08 10:10:08 +02:00
Linus Walleij c663e5f567 gpio: support native single-ended hardware drivers
Some GPIO controllers has a special hardware bit we can flip
to support open drain / source. This means that on these hardwares
we do not need to emulate OD/OS by setting the line to input
instead of actively driving it high/low. Add an optional vtable
callback to the driver set_single_ended() so that driver can
implement this in hardware if they have it.

We may need a pinctrl_gpio_set_config() call at some point to
propagate this down to a backing pin control device on systems
with split GPIO/pin control.

Reported-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-04-05 16:57:15 +02:00
Geert Uytterhoeven 1cfab8f8b3 gpiolib: Fix comment referring to gpio_*() in gpiod_*()
Fixes: 79a9becda8 ("gpiolib: export descriptor-based GPIO interface")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-03-16 13:11:11 +01:00
Linus Walleij 016bf20829 Merge branch 'devm-gpiochip-add-data' into devel 2016-03-08 14:41:41 +07:00
Bamvor Jian Zhang a961f9b472 gpiolib: rewrite gpiodev_add_to_list
The original code of gpiodev_add_to_list is not very clear which
lead to bugs or compiling warning, reference the following patches:
Bugs:
1.  Commit ef7c755303 ("gpiolib: improve overlap check of range of
    gpio").
2.  Commit 96098df125 ("gpiolib: fix chip order in gpio list")

Warning:
1.  Commit e28ecca6ea ("gpio: fix warning about iterator").
of gpio").

There is a off-list discussion about how to improve it consequently.
This commit try to follow this by rewriting the whole functions.

Tested pass with my gpio mockup driver and test scripts[1].

[1] http://www.spinics.net/lists/linux-gpio/msg09598.html

Suggested-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Bamvor Jian Zhang <bamvor.zhangjian@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-03-07 12:02:46 +07:00
Linus Walleij 214338e372 gpio: present the consumer of a line to userspace
I named the field representing the current user of GPIO line as
"label" but this is too vague and ambiguous. Before anyone gets
confused, rename it to "consumer" and indicate clearly in the
documentation that this is a string set by the user of the line.

Also clean up leftovers in the documentation.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-02-25 21:07:23 +01:00
Laxman Dewangan 0cf3292cde gpio: Add devm_ apis for gpiochip_add_data and gpiochip_remove
Add device managed APIs devm_gpiochip_add_data() and
devm_gpiochip_remove() for the APIs gpiochip_add_data()
and gpiochip_remove().

This helps in reducing code in error path and sometimes
removal of .remove callback for driver unbind.

Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
2016-02-23 19:40:33 +05:30
Linus Walleij 9d8cc89c31 gpio: fixup line flags for userspace ABI
This fixes the wrongly indicated lines in the userspace
ABI: test for the right BITS, do not treat bit numbers as
bitmasks.

Reported-by: Markus Pargmann <mpa@pengutronix.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-02-22 13:44:53 +01:00
Bamvor Jian Zhang bd203bd56d gpiolib: fix crash when gpiochip removed
Commit cb464a88e1ed ("gpio: make the gpiochip a real device") call
gpiochip_sysfs_unregister after the gpiochip is empty. It lead to the
following crash:

[  163.503994] Unable to handle kernel NULL pointer dereference at virtual address 0000007c
[...]
[  163.525394] [<ffffffc0003719a0>] gpiochip_sysfs_unregister+0x44/0xa4
[  163.525611] [<ffffffc00036f6a0>] gpiochip_remove+0x24/0x154
[  163.525861] [<ffffffbffc00f0a4>] mockup_gpio_remove+0x38/0x64 [gpio_mockup]
[  163.526101] [<ffffffc00042b4b4>] platform_drv_remove+0x24/0x64
[  163.526313] [<ffffffc000429cc8>] __device_release_driver+0x7c/0xfc
[  163.526525] [<ffffffc000429e54>] driver_detach+0xbc/0xc0
[  163.526700] [<ffffffc000429014>] bus_remove_driver+0x58/0xac
[  163.526883] [<ffffffc00042a4cc>] driver_unregister+0x2c/0x4c
[  163.527067] [<ffffffc00042b5c0>] platform_driver_unregister+0x10/0x18
[  163.527284] [<ffffffbffc00f340>] mock_device_exit+0x10/0x38 [gpio_mockup]
[  163.527593] [<ffffffc00011cefc>] SyS_delete_module+0x1b8/0x1fc
[  163.527799] [<ffffffc000085d8c>] __sys_trace_return+0x0/0x4
[  163.528049] Code: 940d74b4 f9019abf aa1303e0 940d7439 (7940fac0)
[  163.536273] ---[ end trace 3d1329be504af609 ]---

This patch fix this by changing the code back.

Signed-off-by: Bamvor Jian Zhang <bamvor.zhangjian@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-02-20 12:48:34 +01:00
Linus Walleij 521a2ad6f8 gpio: add userspace ABI for GPIO line information
This adds a GPIO line ABI for getting name, label and a few select
flags from the kernel.

This hides the kernel internals and only tells userspace what it
may need to know: the different in-kernel consumers are masked
behind the flag "kernel" and that is all userspace needs to know.

However electric characteristics like active low, open drain etc
are reflected to userspace, as this is important information.

We provide information on all lines on all chips, later on we will
likely add a flag for the chardev consumer so we can filter and
display only the lines userspace actually uses in e.g. lsgpio,
but then we first need an ABI for userspace to grab and use
(get/set/select direction) a GPIO line.

Sample output from "lsgpio" on ux500:

GPIO chip: gpiochip7, "8011e000.gpio", 32 GPIO lines
        line 0: unnamed unlabeled
        line 1: unnamed unlabeled
(...)
        line 25: unnamed "SFH7741 Proximity Sensor" [kernel output open-drain]
        line 26: unnamed unlabeled
(...)

Tested-by: Michael Welling <mwelling@ieee.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-02-19 09:48:46 +01:00
Linus Walleij df4878e969 gpio: store reflect the label to userspace
The gpio_chip label is useful for userspace to understand what
kind of GPIO chip it is dealing with. Let's store a copy of this
label in the gpio_device, add it to the struct passed to userspace
for GPIO_GET_CHIPINFO_IOCTL and modify lsgpio to show it.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-02-19 09:48:41 +01:00
Josh Cartwright 969f07b445 gpio: use kzalloc to allocate gpio_device
The use of kmalloc() to allocate the gpio_device leaves the contained struct
device object in an unknown state.  Calling dev_set_name() on a struct device
of unknown state can trigger the free() of an invalid pointer, as seen in the
following backtrace (collected by Tony Lindgren):

  kfree
  kobject_set_name_vargs
  dev_set_name
  gpiochip_add_data
  omap_gpio_probe
  platform_drv_probe
  ...

Reported-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reported-by: Michael Welling <mwelling@ieee.org>
Reported-by: Tony Lindgren <tony@atomide.com>
Tested-by: Michael Welling <mwelling@ieee.org>
Tested-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Josh Cartwright <joshc@ni.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-02-18 20:45:25 +01:00