Commit Graph

19 Commits

Author SHA1 Message Date
Johan Hovold cef1717b7f gpio: sysfs: move irq trigger flags to class-device data
Move irq trigger flags, which as sysfs-interface specific, to the class
device data.

This avoids accessing the gpio-descriptor flags field using non-atomic
operations without any locking, and allows for a more clear separation
of the sysfs interface from gpiolib core.

Signed-off-by: Johan Hovold <johan@kernel.org>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-05-12 10:47:57 +02:00
Johan Hovold 427fdeef50 gpio: sysfs: remove FLAG_SYSFS_DIR
Remove FLAG_SYSFS_DIR, which is sysfs-interface specific, and store it
in the class-device data instead.

Note that the flag is only used during export.

Signed-off-by: Johan Hovold <johan@kernel.org>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-05-12 10:47:52 +02:00
Johan Hovold a08f5c21f4 gpio: sysfs: clean up interrupt-interface implementation
Store the value sysfs entry in the gpiod data rather than in a global
table accessed through an index stored in the overloaded gpio-descriptor
flag field.

Signed-off-by: Johan Hovold <johan@kernel.org>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-05-12 10:47:19 +02:00
Johan Hovold 426577bd88 gpio: sysfs: rename gpiochip registration functions
Rename the gpio-chip export/unexport functions to the more descriptive
names gpiochip_sysfs_register and gpiochip_sysfs_unregister.

Signed-off-by: Johan Hovold <johan@kernel.org>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-05-12 10:46:49 +02:00
Linus Torvalds 510965dd4a This is the bulk of GPIO changes for the v4.1 development
cycle:
 
 - A new GPIO hogging mechanism has been added. This can
   be used on boards that want to drive some GPIO line high,
   low, or set it as input on boot and then never touch it
   again. For some embedded systems this is bliss and
   simplifies things to a great extent.
 
 - Some API cleanup and closure: gpiod_get_array() and
   gpiod_put_array() has been added to get and put GPIOs
   in bulk as was possible with the non-descriptor API.
 
 - Encapsulate cross-calls to the pin control subsystem in
   <linux/gpio/driver.h>. Now this should be the only header
   any GPIO driver needs to include or something is wrong.
   Cleanups restricting drivers to this include are welcomed
   if tested.
 
 - Sort the GPIO Kconfig and split it into submenus, as
   it was becoming and unstructured, illogical and
   unnavigatable mess. I hope this is easier to follow.
   Menus that require a certain subsystem like I2C can
   now be hidden nicely for example, still working on
   others.
 
 - New drivers:
 
     - New driver for the Altera Soft GPIO.
 
     - The F7188x driver now handles the F71869 and
       F71869A variants.
 
     - The MIPS Loongson driver has been moved to
       drivers/gpio for consolidation and cleanup.
 
 - Cleanups:
 
    - The MAX732x is converted to use the GPIOLIB_IRQCHIP
      infrastructure.
 
    - The PCF857x is converted to use the GPIOLIB_IRQCHIP
      infrastructure.
 
    - Radical cleanup of the OMAP driver.
 
 - Misc:
 
    - Enable the DWAPB GPIO for all architectures. This is
      a "hard IP" block from Synopsys which has started to
      turn up in so diverse architectures as X86 Quark, ARC
      and a slew of ARM systems. So even though it's not an
      expander, it's generic enough to be available for all.
 
    - We add a mock GPIO on Crystalcove PMIC after a long
      discussion with Daniel Vetter et al, tracing back to
      the shootout at the kernel summit where DRM drivers
      and sub-componentization was discussed. In this case
      a mock GPIO is assumed to be the best compromise
      gaining some reuse of infrastructure without making
      DRM drivers overly complex at the same time. Let's
      see.
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Merge tag 'gpio-v4.1-1' 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 v4.1 development cycle:

   - A new GPIO hogging mechanism has been added.  This can be used on
     boards that want to drive some GPIO line high, low, or set it as
     input on boot and then never touch it again.  For some embedded
     systems this is bliss and simplifies things to a great extent.

   - Some API cleanup and closure: gpiod_get_array() and
     gpiod_put_array() has been added to get and put GPIOs in bulk as
     was possible with the non-descriptor API.

   - Encapsulate cross-calls to the pin control subsystem in
     <linux/gpio/driver.h>.  Now this should be the only header any GPIO
     driver needs to include or something is wrong.  Cleanups
     restricting drivers to this include are welcomed if tested.

   - Sort the GPIO Kconfig and split it into submenus, as it was
     becoming and unstructured, illogical and unnavigatable mess.  I
     hope this is easier to follow.  Menus that require a certain
     subsystem like I2C can now be hidden nicely for example, still
     working on others.

   - New drivers:

       - New driver for the Altera Soft GPIO.

       - The F7188x driver now handles the F71869 and F71869A variants.

       - The MIPS Loongson driver has been moved to drivers/gpio for
         consolidation and cleanup.

   - Cleanups:

       - The MAX732x is converted to use the GPIOLIB_IRQCHIP
         infrastructure.

       - The PCF857x is converted to use the GPIOLIB_IRQCHIP
         infrastructure.

       - Radical cleanup of the OMAP driver.

   - Misc:

       - Enable the DWAPB GPIO for all architectures.  This is a "hard
         IP" block from Synopsys which has started to turn up in so
         diverse architectures as X86 Quark, ARC and a slew of ARM
         systems.  So even though it's not an expander, it's generic
         enough to be available for all.

       - We add a mock GPIO on Crystalcove PMIC after a long discussion
         with Daniel Vetter et al, tracing back to the shootout at the
         kernel summit where DRM drivers and sub-componentization was
         discussed.  In this case a mock GPIO is assumed to be the best
         compromise gaining some reuse of infrastructure without making
         DRM drivers overly complex at the same time.  Let's see"

* tag 'gpio-v4.1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (62 commits)
  Revert "gpio: sch: use uapi/linux/pci_ids.h directly"
  gpio: dwapb: remove dependencies
  gpio: dwapb: enable for ARC
  gpio: removing kfree remove functionality
  gpio: mvebu: Fix mask/unmask managment per irq chip type
  gpio: split GPIO drivers in submenus
  gpio: move MFD GPIO drivers under their own comment
  gpio: move BCM Kona Kconfig option
  gpio: arrange SPI Kconfig symbols alphabetically
  gpio: arrange PCI GPIO controllers alphabetically
  gpio: arrange I2C Kconfig symbols alphabetically
  gpio: arrange Kconfig symbols alphabetically
  gpio: ich: Implement get_direction function
  gpio: use (!foo) instead of (foo == NULL)
  gpio: arizona: drop owner assignment from platform_drivers
  gpio: max7300: remove 'ret' variable
  gpio: use devm_kzalloc
  gpio: sch: use uapi/linux/pci_ids.h directly
  gpio: x-gene: fix devm_ioremap_resource() check
  gpio: loongson: Add Loongson-3A/3B GPIO driver support
  ...
2015-04-18 08:22:10 -04:00
Rafael J. Wysocki ce793486e2 driver core / ACPI: Represent ACPI companions using fwnode_handle
Now that we have struct fwnode_handle, we can use that to point to
ACPI companions from struct device objects instead of pointing to
struct acpi_device directly.

There are two benefits from that.  First, the somewhat ugly and
hackish struct acpi_dev_node can be dropped and, second, the same
struct fwnode_handle pointer can be used in the future to point
to other (non-ACPI) firmware device node types.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Grant Likely <grant.likely@linaro.org>
2015-03-16 23:49:03 +01:00
Rojhalat Ibrahim 6685852732 gpiolib: add gpiod_get_array and gpiod_put_array functions
Introduce new functions for conveniently obtaining and disposing of
an entire array of GPIOs with one function call.

ACPI parts tested by Mika Westerberg, DT parts tested by Rojhalat
Ibrahim.

Change log:
v5: move the ACPI functions to gpiolib-acpi.c
v4: - use shorter names for members of struct gpio_descs
    - rename lut_gpio_count to platform_gpio_count for clarity
    - add check for successful memory allocation
    - use ERR_CAST()
v3: - rebase on current linux-gpio devel branch
    - fix ACPI GPIO counting
    - allow for zero-sized arrays
    - make the flags argument mandatory for the new functions
    - clarify documentation
v2: change interface

Suggested-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Rojhalat Ibrahim <imr@rtschenk.de>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Tested-by: Rojhalat Ibrahim <imr@rtschenk.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-03-05 09:52:28 +01:00
Rojhalat Ibrahim 7f2e553a71 gpiolib: define gpio suffixes globally
Avoid multiple identical definitions of the gpio suffix strings by putting
them into a global constant array.

Signed-off-by: Rojhalat Ibrahim <imr@rtschenk.de>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-03-05 09:48:51 +01:00
Benoit Parrot f625d46017 gpio: add GPIO hogging mechanism
Based on Boris Brezillion's work this is a reworked patch
of his initial GPIO hogging mechanism.
This patch provides a way to initially configure specific GPIO
when the GPIO controller is probed.

The actual DT scanning to collect the GPIO specific data is performed
as part of gpiochip_add().

The purpose of this is to allow specific GPIOs to be configured
without any driver specific code.
This is particularly useful because board design are getting
increasingly complex and given SoC pins can now have more
than 10 mux values, a lot of connections are now dependent on
external IO muxes to switch various modes.

Specific drivers should not necessarily need to be aware of
what accounts to a specific board implementation. This board level
"description" should be best kept as part of the dts file.

Signed-off-by: Benoit Parrot <bparrot@ti.com>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-03-04 11:09:00 +01:00
Johan Hovold ebbeba120a gpio: sysfs: fix gpio attribute-creation race
Fix attribute-creation race with userspace by using the default group
to create also the contingent gpio device attributes.

Fixes: d8f388d8dc ("gpio: sysfs interface")
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-01-15 17:20:56 +01:00
Mika Westerberg 0d9a693cc8 gpio / ACPI: Add support for _DSD device properties
With release of ACPI 5.1 and _DSD method we can finally name GPIOs (and
other things as well) returned by _CRS. Previously we were only able to
use integer index to find the corresponding GPIO, which is pretty error
prone if the order changes.

With _DSD we can now query GPIOs using name instead of an integer index,
like the below example shows:

  // Bluetooth device with reset and shutdown GPIOs
  Device (BTH)
  {
      Name (_HID, ...)

      Name (_CRS, ResourceTemplate ()
      {
          GpioIo (Exclusive, PullUp, 0, 0, IoRestrictionInputOnly,
                  "\\_SB.GPO0", 0, ResourceConsumer) {15}
          GpioIo (Exclusive, PullUp, 0, 0, IoRestrictionInputOnly,
                  "\\_SB.GPO0", 0, ResourceConsumer) {27, 31}
      })

      Name (_DSD, Package ()
      {
          ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"),
          Package ()
	  {
              Package () {"reset-gpio", Package() {^BTH, 1, 1, 0 }},
              Package () {"shutdown-gpio", Package() {^BTH, 0, 0, 0 }},
          }
      })
  }

The format of the supported GPIO property is:

  Package () { "name", Package () { ref, index, pin, active_low }}

  ref - The device that has _CRS containing GpioIo()/GpioInt() resources,
        typically this is the device itself (BTH in our case).
  index - Index of the GpioIo()/GpioInt() resource in _CRS starting from zero.
  pin - Pin in the GpioIo()/GpioInt() resource. Typically this is zero.
  active_low - If 1 the GPIO is marked as active_low.

Since ACPI GpioIo() resource does not have field saying whether it is
active low or high, the "active_low" argument can be used here. Setting
it to 1 marks the GPIO as active low.

In our Bluetooth example the "reset-gpio" refers to the second GpioIo()
resource, second pin in that resource with the GPIO number of 31.

This patch implements necessary support to gpiolib for extracting GPIOs
using _DSD device properties.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Grant Likely <grant.likely@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-11-04 21:58:22 +01:00
Mika Westerberg afa82fab5e gpio / ACPI: Move event handling registration to gpiolib irqchip helpers
Since now we have irqchip helpers that the GPIO chip drivers are supposed
to use if possible, we can move the registration of ACPI events to happen
in these helpers. This seems to be more natural place and might encourage
GPIO chip driver writers to take advantage of the irqchip helpers.

We make the functions available to GPIO chip drivers via private gpiolib.h,
just in case generic irqchip helpers are not suitable.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-07-28 12:23:57 +02:00
Guenter Roeck f7d4ad98fd gpiolib: Export gpiochip_request_own_desc and gpiochip_free_own_desc
Both functions were introduced to let gpio drivers request their own
gpio pins. Without exporting the functions, this can however only be
used by gpio drivers built into the kernel.

Secondary impact is that the functions can not currently be used by
platform initialization code associated with the gpio-pca953x driver.
This code permits auto-export of gpio pins through platform data, but
if this functionality is used, the module can no longer be unloaded due
to the problem solved with the introduction of gpiochip_request_own_desc
and gpiochip_free_own_desc.

Export both function so they can be used from modules and from
platform initialization code.

Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-07-24 10:25:00 +02:00
Alexandre Courbot 1bd6b601fe gpio: make gpiochip_get_desc() gpiolib-private
As GPIO descriptors are not going to remain unique anymore, having this
function public is not safe. Restrain its use to gpiolib since we have
no user outside of it.

Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-07-23 17:41:12 +02:00
Alexandre Courbot 0eb4c6c267 gpio: move sysfs support to its own file
sysfs support is currently entangled within the core GPIO support, while
it should relly just be a (privileged) user of the integer GPIO API.
This patch is a first step towards making the gpiolib code more readable
by splitting it into logical parts.

Move all sysfs support to their own source file, and share static
members of gpiolib that need to be in the private gpiolib.h file. In
the future we will want to put some of them back into gpiolib.c, but this
first patch let us at least identify them.

Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-07-09 12:22:57 +02:00
Alexandre Courbot f01d907582 gpio: make of_get_named_gpiod_flags() private
of_get_named_gpiod_flags() is visible and directly usable by GPIO
consumers, but it really should not as the gpiod interface relies
on the simpler gpiod_get() to provide properly-configured GPIOs.

of_get_named_gpiod_flags() is just used internally by gpiolib to
implement gpiod_get(), and by the old of_get_named_gpio_flags()
function, therefore it makes sense to make it gpiolib-private.

As a side-effect, the unused (and unneeded) of_get_gpiod_flags()
inline function is also removed, and of_get_named_gpio_flags() is moved
from a static inline function to a regular one in gpiolib-of.c

This results in all references to gpiod_* functions in of_gpio.h being
gone, which is the way it should be since this file is part of the old
integer GPIO interface.

Changes since v1:
- Fixed compilation error when CONFIG_OF_GPIO is not defined
- Fixed warning due to of_gpio_flags enum not being declared
  in private gpiolib.h header

Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-05-21 11:14:46 +02:00
Mika Westerberg 77c2d7929d gpiolib: Allow GPIO chips to request their own GPIOs
Sometimes it is useful to allow GPIO chips themselves to request GPIOs they
own through gpiolib API. One use case is ACPI ASL code that should be able
to toggle GPIOs through GPIO operation regions.

We can't use gpio_request() because it will pin the module to the kernel
forever (it calls try_module_get()). To solve this we move module refcount
manipulation to gpiod_request() and let __gpiod_request() handle the actual
request. This changes the sequence a bit as now try_module_get() is called
outside of gpio_lock (I think this is safe, try_module_get() handles
serialization it needs already).

Then we provide gpiolib internal functions gpiochip_request/free_own_desc()
that do the same as gpio_request() but don't manipulate module refrence
count. This allows the GPIO chip driver to request and free descriptors it
owns without being pinned to the kernel forever.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-03-13 10:32:18 +01:00
Mika Westerberg 5ccff85276 gpio / ACPI: get rid of acpi_gpio.h
Now that all users of acpi_gpio.h have been moved to use either the GPIO
descriptor interface or to the internal gpiolib.h we can get rid of
acpi_gpio.h entirely.

Once this is done the only interface to get GPIOs to drivers enumerated
from ACPI namespace is the descriptor based interface.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-01-08 15:07:28 +01:00
Mika Westerberg 664e3e5ac6 gpio / ACPI: register to ACPI events automatically
Instead of asking each driver to register to ACPI events we can just call
acpi_gpiochip_register_interrupts() for each chip that has an ACPI handle.
The function checks chip->to_irq and if it is set to NULL (a GPIO driver
that doesn't do interrupts) the function does nothing.

We also add the a new header drivers/gpio/gpiolib.h that is used for
functions internal to gpiolib and add ACPI GPIO chip registering functions
to that header.

Once that is done we can remove call to acpi_gpiochip_register_interrupts()
from its only user, pinctrl-baytrail.c

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-01-08 15:07:28 +01:00