Commit Graph

288 Commits

Author SHA1 Message Date
Linus Torvalds
a1df7efeda This is the GPIO bulk changes for the v3.20 series:
- GPIOLIB core changes:
   - Create and use of_mm_gpiochip_remove() for removing
     memory-mapped OF GPIO chips
   - GPIO MMIO library suppports bgpio_set_multiple for
     switching several lines at once, a feature merged in
     the last cycle.
 - New drivers:
   - New driver for the APM X-gene standby GPIO controller
   - New driver for the Fujitsu MB86S7x GPIO controller
 - Cleanups:
   - Moved rcar driver to use gpiolib irqchip
   - Moxart converted to the GPIO MMIO library
   - GE driver converted to GPIO MMIO library
   - Move sx150x to irqdomain
   - Move max732x to irqdomain
   - Move vx855 to use managed resources
   - Move dwapb to use managed resources
   - Clean tc3589x from platform data
   - Clean stmpe driver to use device tree only probe
 - New subtypes:
   - sx1506 support in the sx150x driver
   - Quark 1000 SoC support in the SCH driver
   - Support X86 in the Xilinx driver
   - Support PXA1928 in the PXA driver
 - Extended drivers:
   - max732x supports device tree probe
   - sx150x supports device tree probe
 - Various minor cleanups and bug fixes
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Merge tag 'gpio-v3.20-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio

Pull GPIO changes from Linus Walleij:
 "This is the GPIO bulk changes for the v3.20 series:

  GPIOLIB core changes:
   - Create and use of_mm_gpiochip_remove() for removing memory-mapped
     OF GPIO chips
   - GPIO MMIO library suppports bgpio_set_multiple for switching
     several lines at once, a feature merged in the last cycle.

  New drivers:
   - New driver for the APM X-gene standby GPIO controller
   - New driver for the Fujitsu MB86S7x GPIO controller

  Cleanups:
   - Moved rcar driver to use gpiolib irqchip
   - Moxart converted to the GPIO MMIO library
   - GE driver converted to GPIO MMIO library
   - Move sx150x to irqdomain
   - Move max732x to irqdomain
   - Move vx855 to use managed resources
   - Move dwapb to use managed resources
   - Clean tc3589x from platform data
   - Clean stmpe driver to use device tree only probe

  New subtypes:
   - sx1506 support in the sx150x driver
   - Quark 1000 SoC support in the SCH driver
   - Support X86 in the Xilinx driver
   - Support PXA1928 in the PXA driver

  Extended drivers:
   - max732x supports device tree probe
   - sx150x supports device tree probe

  Various minor cleanups and bug fixes"

* tag 'gpio-v3.20-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (61 commits)
  gpio: kconfig: replace PPC_OF with PPC
  gpio: pxa: add PXA1928 gpio type support
  dt/bindings: gpio: add compatible string for marvell,pxa1928-gpio
  gpio: pxa: remove mach IRQ includes
  gpio: max732x: use an inline function for container cast
  gpio: use sizeof() instead of hardcoded values
  gpio: max732x: add set_multiple function
  gpio: sch: Consolidate similar algorithms
  gpio: tz1090-pdc: Use resource_size to fix off-by-one resource size calculation
  gpio: ge: Convert to use devm_kstrdup
  gpio: correctly use const char * const
  gpio: sx150x: fixup OF support
  gpio: mpc8xxx: Use of_mm_gpiochip_remove
  gpio: Add Fujitsu MB86S7x GPIO driver
  gpio: mpc8xxx: Convert to platform device interface.
  gpio: zevio: Use of_mm_gpiochip_remove
  gpio: gpio-mm-lantiq: Use of_mm_gpiochip_remove
  gpio: gpio-mm-lantiq: Use of_property_read_u32
  gpio: gpio-mm-lantiq: Do not replicate code
  gpio :gpio-mm-lantiq: Use devm_kzalloc
  ...
2015-02-11 11:17:34 -08:00
Olliver Schinagl
9e089246a5 gpio: use sizeof() instead of hardcoded values
gpiolib uses a fixed string for the suffixes and defines it at 32 bytes.
Later in the code snprintf is used with this fixed value of 32. Using
sizeof() is safer in case the size for the suffixes is ever changed.

Signed-off-by: Olliver Schinagl <oliver@schinagl.nl>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-01-30 14:43:04 +01:00
Olliver Schinagl
ef3b2bd6f3 gpio: correctly use const char * const
On my previous patch I was overly hasty and made the suffixes string
array
const char const *suffixes, instaed of const char * const suffixes. This
patch corrects that

Signed-off-by: Olliver Schinagl <oliver@schinagl.nl>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-01-29 10:29:53 +01:00
Olliver Schinagl
b9b4d9f2b9 gpio:gpiolib: use static const char const * for a suffixes array
Checkpatch complains, and probably with good reason that we should use
const char const * for the static constant array that never gets
changed.

Signed-off-by: Olliver Schinagl <oliver@schinagl.nl>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-01-15 17:23:22 +01:00
Johan Hovold
01cca93a94 gpio: unregister gpiochip device before removing it
Unregister gpiochip device (used to export information through sysfs)
before removing it internally. This way removal will reverse addition.

Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-01-14 14:27:01 +01:00
Johan Hovold
6798acaa01 gpio: fix sleep-while-atomic in gpiochip_remove
Move direct and indirect calls to gpiochip_remove_pin_ranges outside of
spin lock as they can end up taking a mutex in pinctrl_remove_gpio_range.

Note that the pin ranges are already added outside of the lock.

Fixes: 9ef0d6f762 ("gpiolib: call pin removal in chip removal function")
Fixes: f23f1516b6 ("gpiolib: provide provision to register pin ranges")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-01-14 14:26:25 +01:00
Johan Hovold
00acc3dc24 gpio: fix memory leak and sleep-while-atomic
Fix memory leak and sleep-while-atomic in gpiochip_remove.

The memory leak was introduced by afa82fab5e ("gpio / ACPI: Move event
handling registration to gpiolib irqchip helpers") that moved the
release of acpi interrupt resources to gpiochip_irqchip_remove, but by
then the resources are no longer accessible as the acpi_gpio_chip has
already been freed by acpi_gpiochip_remove.

Note that this also fixes a few potential sleep-while-atomics, which has
been around since 1425052097 ("gpio: add IRQ chip helpers in gpiolib")
when the call to gpiochip_irqchip_remove while holding a spinlock was
added (a couple of irq-domain paths can end up grabbing mutexes).

Fixes: afa82fab5e ("gpio / ACPI: Move event handling registration to
gpiolib irqchip helpers")
Fixes: 1425052097 ("gpio: add IRQ chip helpers in gpiolib")
Cc: stable <stable@vger.kernel.org>

Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-01-14 14:25:48 +01:00
Johan Hovold
05aa520334 gpio: clean up gpiochip_add error handling
Clean up gpiochip_add error handling.

Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-01-14 14:25:09 +01:00
Johan Hovold
225fce83cb gpio: fix gpio-chip list corruption
Fix potential corruption of gpio-chip list due to failure to remove the
chip from the list before returning in gpiochip_add error path.

The chip could be long gone when the global list is next traversed,
something which could lead to a null-pointer dereference. In the best
case (chip not deallocated) we are just leaking the gpio range.

Fixes: 14e85c0e69 ("gpio: remove gpio_descs global array")
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-01-14 14:24:29 +01:00
Johan Hovold
5539b3c938 gpio: fix memory and reference leaks in gpiochip_add error path
Memory allocated and references taken by of_gpiochip_add and
acpi_gpiochip_add were never released on errors in gpiochip_add (e.g.
failure to find free gpio range).

Fixes: 391c970c0d ("of/gpio: add default of_xlate function if device
has a node pointer")
Fixes: 664e3e5ac6 ("gpio / ACPI: register to ACPI events
automatically")
Cc: stable <stable@vger.kernel.org>

Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-01-14 14:23:47 +01:00
Linus Torvalds
980f3c344f This is the bulk of GPIO changes for the v3.19 series:
- A new API that allows setting more than one GPIO at the
   time. This is implemented for the new descriptor-based
   API only and makes it possible to e.g. toggle a clock and
   data line at the same time, if the hardware can do this
   with a single register write. Both consumers and drivers
   need new calls, and the core will fall back to driving
   individual lines where needed. Implemented for the MPC8xxx
   driver initially.
 - Patched the mdio-mux-gpio and the serial mctrl driver
   that drives modems to use the new multiple-setting API
   to set several signals simultaneously.
 - Get rid of the global GPIO descriptor array, and instead
   allocate descriptors dynamically for each GPIO on a certain
   GPIO chip. This moves us closer to getting rid of the
   limitation of using the global, static GPIO numberspace.
 - New driver and device tree bindings for 74xx ICs.
 - New driver and device tree bindings for the VF610 Vybrid.
 - Support the RCAR r8a7793 and r8a7794.
 - Guidelines for GPIO device tree bindings trying to get
   things a bit more strict with the advent of combined
   device properties.
 - Suspend/resume support for the MVEBU driver.
 - A slew of minor fixes and improvements.
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Merge tag 'gpio-v3.19-2' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio

Pull take two of the GPIO updates:
 "Same stuff as last time, now with a fixup patch for the previous
  compile error plus I ran a few extra rounds of compile-testing.

  This is the bulk of GPIO changes for the v3.19 series:

   - A new API that allows setting more than one GPIO at the time.  This
     is implemented for the new descriptor-based API only and makes it
     possible to e.g. toggle a clock and data line at the same time, if
     the hardware can do this with a single register write.  Both
     consumers and drivers need new calls, and the core will fall back
     to driving individual lines where needed.  Implemented for the
     MPC8xxx driver initially

   - Patched the mdio-mux-gpio and the serial mctrl driver that drives
     modems to use the new multiple-setting API to set several signals
     simultaneously

   - Get rid of the global GPIO descriptor array, and instead allocate
     descriptors dynamically for each GPIO on a certain GPIO chip.  This
     moves us closer to getting rid of the limitation of using the
     global, static GPIO numberspace

   - New driver and device tree bindings for 74xx ICs

   - New driver and device tree bindings for the VF610 Vybrid

   - Support the RCAR r8a7793 and r8a7794

   - Guidelines for GPIO device tree bindings trying to get things a bit
     more strict with the advent of combined device properties

   - Suspend/resume support for the MVEBU driver

   - A slew of minor fixes and improvements"

* tag 'gpio-v3.19-2' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (33 commits)
  gpio: mcp23s08: fix up compilation error
  gpio: pl061: document gpio-ranges property for bindings file
  gpio: pl061: hook request if gpio-ranges avaiable
  gpio: mcp23s08: Add option to configure IRQ output polarity as active high
  gpio: fix deferred probe detection for legacy API
  serial: mctrl_gpio: use gpiod_set_array function
  mdio-mux-gpio: Use GPIO descriptor interface and new gpiod_set_array function
  gpio: remove const modifier from gpiod_get_direction()
  gpio: remove gpio_descs global array
  gpio: mxs: implement get_direction callback
  gpio: em: Use dynamic allocation of GPIOs
  gpio: Check if base is positive before calling gpio_is_valid()
  gpio: mcp23s08: Add simple IRQ support for SPI devices
  gpio: mcp23s08: request a shared interrupt
  gpio: mcp23s08: Do not free unrequested interrupt
  gpio: rcar: Add r8a7793 and r8a7794 support
  gpio-mpc8xxx: add mpc8xxx_gpio_set_multiple function
  gpiolib: allow simultaneous setting of multiple GPIO outputs
  gpio: mvebu: add suspend/resume support
  gpio: gpio-davinci: remove duplicate check on resource
  ..
2014-12-14 14:05:05 -08:00
Alexandre Courbot
0e9a5edf5d gpio: fix deferred probe detection for legacy API
Commit 14e85c0e69 ("gpio: remove gpio_descs global array") changed
gpio_to_desc()'s behavior to return NULL not only for GPIOs numbers
not in the valid range, but also for all GPIOs whose controller has not
been probed yet. Although this behavior is more correct (nothing hints
that these GPIO numbers will be populated later), this affects
gpio_request() and gpio_request_one() which call gpiod_request() with a
NULL descriptor, causing it to return -EINVAL instead of the expected
-EPROBE_DEFER for a non-probed GPIO.

gpiod_request() is only called with a descriptor obtained from
gpio_to_desc() from these two functions, so address the issue there.

Other ways to obtain GPIOs rely on well-defined mappings and can thus
return -EPROBE_DEFER only for relevant GPIOs, and are thus not affected
by this issue.

Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-12-02 15:46:36 +01:00
Alexandre Courbot
8e53b0f190 gpio: remove const modifier from gpiod_get_direction()
Although gpiod_get_direction() can be considered side-effect free for
consumers, its internals involve setting or clearing bits in the
affected GPIO descriptor, for which we need to force-cast the const
descriptor variable to non-const. This could lead to incorrect behavior
if the compiler decides to optimize here, so remove this const
attribute. The intent is to make gpiod_get_direction() private anyway,
so it does not really matter.

Reported-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-11-28 14:43:36 +01:00
Alexandre Courbot
14e85c0e69 gpio: remove gpio_descs global array
Replace the ARCH_NR_GPIOS-sized static array of GPIO descriptors by
dynamically-allocated arrays for each GPIO chip.

This change makes gpio_to_desc() perform in O(n) (where n is the number
of GPIO chips registered) instead of O(1), however since n is rarely
bigger than 1 or 2 no noticeable performance issue is expected.
Besides this provides more incentive for GPIO consumers to move to the
gpiod interface. One could use a O(log(n)) structure to link the GPIO
chips together, but considering the low limit of n the hypothetical
performance benefit is probably not worth the added complexity.

This patch uses kcalloc() in gpiochip_add(), which removes the ability
to add a chip before kcalloc() can operate. I am not aware of such
cases, but if someone bisects up to this patch then I will be proven
wrong...

Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-11-28 11:28:23 +01:00
Geert Uytterhoeven
86256d1fce gpio: Check if base is positive before calling gpio_is_valid()
It doesn't make much sense to make some (possible expensive) calls to
gpio_is_valid() first, and to ignore the result if the base number is
negative. Check for a positive base number first.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-11-27 15:11:18 +01:00
Rojhalat Ibrahim
5f42424354 gpiolib: allow simultaneous setting of multiple GPIO outputs
Introduce new functions gpiod_set_array & gpiod_set_raw_array to the consumer
interface which allow setting multiple outputs with just one function call.
Also add an optional set_multiple function to the driver interface. Without an
implementation of that function in the chip driver outputs are set
sequentially.

Implementing the set_multiple function in a chip driver allows for:
- Improved performance for certain use cases. The original motivation for this
  was the task of configuring an FPGA. In that specific case, where 9 GPIO
  lines have to be set many times, configuration time goes down from 48 s to
  20 s when using the new function.
- Simultaneous glitch-free setting of multiple pins on any kind of parallel
  bus attached to GPIOs provided they all reside on the same chip and bank.

Limitations:
  Performance is only improved for normal high-low outputs. Open drain and
  open source outputs are always set separately from each other. Those kinds
  of outputs could probably be accelerated in a similar way if we could
  forgo the error checking when setting GPIO directions.

Change log:
  v6: - rebase on current linux-gpio devel branch
  v5: - check can_sleep property per chip
      - remove superfluous checks
      - supplement documentation
  v4: - add gpiod_set_array function for setting logical values
      - change interface of the set_multiple driver function to use
        unsigned long as type for the bit fields
      - use generic bitops (which also use unsigned long for bit fields)
      - do not use ARCH_NR_GPIOS any more
  v3: - add documentation
      - change commit message
  v2: - use descriptor interface
      - allow arbitrary groups of GPIOs spanning multiple chips

Signed-off-by: Rojhalat Ibrahim <imr@rtschenk.de>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Reviewed-by: Mark Brown <broonie@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-11-27 15:01:18 +01:00
Mika Westerberg
40b7318319 gpio: Support for unified device properties interface
Some drivers need to deal with only firmware representation of its
GPIOs. An example would be a GPIO button array driver where each button
is described as a separate firmware node in device tree. Typically these
child nodes do not have physical representation in the Linux device
model.

In order to help device drivers to handle such firmware child nodes we
add dev[m]_get_named_gpiod_from_child() that takes a child firmware
node pointer as its second argument (the first one is the parent device
itself), finds the GPIO using whatever is the underlying firmware
method, and requests the GPIO properly.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: Alexandre Courbot <acourbot@nvidia.com>
Acked-by: Grant Likely <grant.likely@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-11-04 21:58:23 +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
Alexandre Courbot
e3a2e87893 gpio: rename gpio_lock_as_irq to gpiochip_lock_as_irq
This function actually operates on a gpio_chip, so its prefix should
reflect that fact for consistency with other functions defined in
gpio/driver.h.

Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-10-28 17:30:59 +01:00
Linus Torvalds
ea584595fc This is the bulk of GPIO changes for the v3.18 development
cycle:
 
 - Increase the default ARCH_NR_GPIO from 256 to 512. This
   was done to avoid having a custom <asm/gpio.h> header for
   the x86 architecture - GPIO is custom and complicated
   enough as it is already! We want to move to a radix to
   store the descriptors going forward, and finally get rid
   of this fixed array size altogether.
 
 - Endgame patching of the gpio_remove() semantics initiated
   by Abdoulaye Berthe. It is not accepted by the system that
   the removal of a GPIO chip fails during e.g. reboot or
   shutdown, and therefore the return value has now painfully
   been refactored away. For special cases like GPIO expanders
   on a hot-pluggable bus like USB, we may later add some
   gpiochip_try_remove() call, but for the cases we have now,
   return values are moot.
 
 - Some incremental refactoring of the gpiolib core and ACPI
   GPIO library for more descriptor usage.
 
 - Refactor the chained IRQ handler set-up method to handle
   also threaded, nested interrupts and set up the parent IRQ
   correctly. Switch STMPE and TC3589x drivers to use this
   registration method.
 
 - Add a .irq_not_threaded flag to the struct gpio_chip, so
   that also GPIO expanders that block but are still not
   using threaded IRQ handlers.
 
 - New drivers for the ARM64 X-Gene SoC GPIO controller.
 
 - The syscon GPIO driver has been improved to handle the
   "DSP GPIO" found on the TI Keystone 2 SoC:s.
 
 - ADNP driver switched to use gpiolib irqchip helpers.
 
 - Refactor the DWAPB driver to support being instantiated
   from and MFD cell (platform device).
 
 - Incremental feature improvement in the Zynq, MCP23S08,
   DWAPB, OMAP, Xilinx and Crystalcove drivers.
 
 - Various minor fixes.
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Merge tag 'gpio-v3.18-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio

Pull GPIO changes from Linus Walleij:
 "This is the bulk of GPIO changes for the v3.18 development cycle:

   - Increase the default ARCH_NR_GPIO from 256 to 512.  This was done
     to avoid having a custom <asm/gpio.h> header for the x86
     architecture - GPIO is custom and complicated enough as it is
     already! We want to move to a radix to store the descriptors going
     forward, and finally get rid of this fixed array size altogether.

   - Endgame patching of the gpio_remove() semantics initiated by
     Abdoulaye Berthe.  It is not accepted by the system that the
     removal of a GPIO chip fails during eg reboot or shutdown, and
     therefore the return value has now painfully been refactored away.
     For special cases like GPIO expanders on a hot-pluggable bus like
     USB, we may later add some gpiochip_try_remove() call, but for the
     cases we have now, return values are moot.

   - Some incremental refactoring of the gpiolib core and ACPI GPIO
     library for more descriptor usage.

   - Refactor the chained IRQ handler set-up method to handle also
     threaded, nested interrupts and set up the parent IRQ correctly.
     Switch STMPE and TC3589x drivers to use this registration method.

   - Add a .irq_not_threaded flag to the struct gpio_chip, so that also
     GPIO expanders that block but are still not using threaded IRQ
     handlers.

   - New drivers for the ARM64 X-Gene SoC GPIO controller.

   - The syscon GPIO driver has been improved to handle the "DSP GPIO"
     found on the TI Keystone 2 SoC:s.

   - ADNP driver switched to use gpiolib irqchip helpers.

   - Refactor the DWAPB driver to support being instantiated from and
     MFD cell (platform device).

   - Incremental feature improvement in the Zynq, MCP23S08, DWAPB, OMAP,
     Xilinx and Crystalcove drivers.

   - Various minor fixes"

* tag 'gpio-v3.18-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (52 commits)
  gpio: pch: Build context save/restore only for PM
  pinctrl: abx500: get rid of unused variable
  gpio: ks8695: fix 'else should follow close brace '}''
  gpio: stmpe: add verbose debug code
  gpio: stmpe: fix up interrupt enable logic
  gpio: staticize xway_stp_init()
  gpio: handle also nested irqchips in the chained handler set-up
  gpio: set parent irq on chained handlers
  gpiolib: irqchip: use irq_find_mapping while removing irqchip
  gpio: crystalcove: support virtual GPIO
  pinctrl: bcm281xx: make Kconfig dependency more strict
  gpio: kona: enable only on BCM_MOBILE or for compile testing
  gpio, bcm-kona, LLVMLinux: Remove use of __initconst
  gpio: Fix ngpio in gpio-xilinx driver
  gpio: dwapb: fix pointer to integer cast
  gpio: xgene: Remove unneeded #ifdef CONFIG_OF guard
  gpio: xgene: Remove unneeded forward declation for struct xgene_gpio
  gpio: xgene: Fix missing spin_lock_init()
  gpio: ks8695: fix switch case indentation
  gpiolib: add irq_not_threaded flag to gpio_chip
  ...
2014-10-09 14:58:15 -04:00
Linus Walleij
3f97d5fcf9 gpio: handle also nested irqchips in the chained handler set-up
To unify how we connect cascaded IRQ chips to parent IRQs, if
NULL us passed as handler to the gpiochip_set_chained_irqchip()
function, assume the chips is nested rather than chained, and
we still get the parent set up correctly by way of this function
call.

Alter the drivers for tc3589x and stmpe to use this to set up
their chained handlers as a demonstration of the usage.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-09-26 14:39:08 +02:00
Linus Walleij
83141a7719 gpio: set parent irq on chained handlers
If the IRQ from the parent is nested the IRQ may need to be
resent under certain conditions. Currently the chained IRQ
handler in gpiolib does not handle connecting nested IRQs
but it is conceptually correct to indicate the actual parent
IRQ.

Reported-by: Grygorii Strashko <grygorii.strashko@ti.com>
Reported-by: Lothar Waßmann <LW@karo-electronics.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-09-26 14:35:54 +02:00
Grygorii Strashko
e3893386b9 gpiolib: irqchip: use irq_find_mapping while removing irqchip
There is no guarantee that VIRQs will be allocated sequentially
for gpio irqchip in gpiochip_irqchip_add().
Therefore, it's unsafe to dispose VIRQ in gpiochip_irqchip_remove()
basing on index relatively to stored irq_base value.

Hence, use irq_find_mapping for VIRQ finding  in gpiochip_irqchip_remove()
instead of irq_base + index.

Reported-by: Wang, Yalin <Yalin.Wang@sonymobile.com>
Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-09-26 10:40:11 +02:00
Octavian Purdila
295494af06 gpiolib: add irq_not_threaded flag to gpio_chip
Some GPIO chips (e.g. the DLN2 USB adapter) have blocking get/set
operation but do not need a threaded irq handler.

Signed-off-by: Octavian Purdila <octavian.purdila@intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-09-24 10:53:42 +02:00
Jarkko Nikula
324b039878 gpio: Fix potential NULL handler data in chained irqchip handler
There is possibility with misconfigured pins that interrupt occurs instantly
after setting irq_set_chained_handler() in gpiochip_set_chained_irqchip().
Now if handler gets called before irq_set_handler_data() the handler gets
NULL handler data.

Fix this by moving irq_set_handler_data() call before
irq_set_chained_handler() in gpiochip_set_chained_irqchip().

Cc: Stable <stable@vger.kernel.org> # 3.15+
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
2014-09-24 09:47:20 +02:00
Adrian Hunter
72f908c88c gpio: Fix gpio direction flags not getting set
GPIO direction flags are not getting set because
an 'if' statement is the wrong way around.

Cc: Stable <stable@vger.kernel.org> # 3.15+
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Acked-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-09-24 09:47:12 +02:00
Alexander Shiyan
43a8785aee GPIO: gpiolib: trivial: Add missing carriage return
Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-09-23 17:51:40 +02:00
abdoulaye berthe
e1db1706c8 gpio: gpiolib: set gpiochip_remove retval to void
This avoids handling gpiochip remove error in device
remove handler.

Signed-off-by: Abdoulaye Berthe <berthe.ab@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-09-23 17:51:36 +02:00
Alexandre Courbot
abdc08a3a2 gpio: change gpiochip_request_own_desc() prototype
The current prototype of gpiochip_request_own_desc() requires to obtain
a pointer to a descriptor. This is in contradiction to all other GPIO
request schemes, and imposes an extra step of obtaining a descriptor to
drivers. Most drivers actually cannot even perform that step since the
function that does it (gpichip_get_desc()) is gpiolib-private.

Change gpiochip_request_own_desc() to return a descriptor from a
(chip, hwnum) tuple and update users of this function (currently
gpiolib-acpi only).

Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-08-29 08:58:34 +02:00
Alexandre Courbot
39b2bbe3d7 gpio: add flags argument to gpiod_get*() functions
The huge majority of GPIOs have their direction and initial value set
right after being obtained by one of the gpiod_get() functions. The
integer GPIO API had gpio_request_one() that took a convenience flags
parameter allowing to specify an direction and value applied to the
returned GPIO. This feature greatly simplifies client code and ensures
errors are always handled properly.

A similar feature has been requested for the gpiod API. Since setting
the direction of a GPIO is so often the very next action done after
obtaining its descriptor, we prefer to extend the existing functions
instead of introducing new functions that would raise the
number of gpiod getters to 16 (!).

The drawback of this approach is that all gpiod clients need to be
updated. To limit the pain, temporary macros are introduced that allow
gpiod_get*() to be called with or without the extra flags argument. They
will be removed once all consumer code has been updated.

Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Reviewed-by: Mark Brown <broonie@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-07-28 12:28:05 +02:00
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
Linus Walleij
0a6d315827 gpio: split gpiod board registration into machine header
As per example from the regulator subsystem: put all defines and
functions related to registering board info for GPIO descriptors
into a separate <linux/gpio/machine.h> header.

Cc: Andrew Victor <linux@maxim.org.za>
Cc: Nicolas Ferre <nicolas.ferre@atmel.com>
Cc: Jean-Christophe Plagniol-Villard <plagnioj@jcrosoft.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Thierry Reding <thierry.reding@gmail.com>
Acked-by: Stephen Warren <swarren@wwwdotorg.org>
Reviewed-by: Alexandre Courbot <gnurou@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-07-28 12:23:35 +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
d82da79722 gpio: move gpio_ensure_requested() into legacy C file
gpio_ensure_requested() only makes sense when using the integer-based
GPIO API, so make sure it is called from there instead of the gpiod
API which we know cannot be called with a non-requested GPIO anyway.

The uses of gpio_ensure_requested() in the gpiod API were kind of
out-of-place anyway, so putting them in gpio-legacy.c helps clearing the
code.

Actually, considering the time this ensure_requested mechanism has been
around, maybe we should just turn this patch into "remove
gpio_ensure_requested()" if we know for sure that no user depend on it
anymore?

Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-07-23 17:46:00 +02:00
Alexandre Courbot
d74be6dfea gpio: remove gpiod_lock/unlock_as_irq()
gpio_lock/unlock_as_irq() are working with (chip, offset) arguments and
are thus not using the old integer namespace. Therefore, there is no
reason to have gpiod variants of these functions working with
descriptors, especially since the (chip, offset) tuple is more suitable
to the users of these functions (GPIO drivers, whereas GPIO descriptors
are targeted at GPIO consumers).

Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-07-23 17:43:24 +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
122c94dec7 gpio: move integer GPIO support to its own file
The old integer GPIO interface is, in effect, a privileged user of the
gpiod interface. Reflect this fact further by moving legacy GPIO support
into its own source file. This makes the code clearer and will allow us
to disable legacy GPIO support in the (far) future.

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
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
9c8318ff70 gpio: always compile label support
Compiling out GPIO labels results in a space gain so small that it can
hardly be justified. Labels can also be useful for printing debug
messages, so always keep them around.

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
Tony Lindgren
06fc3b70f1 gpio: of: Fix handling for deferred probe for -gpio suffix
Commit dd34c37aa3 (gpio: of: Allow -gpio suffix for property names)
added parsing for both -gpio and -gpios suffix but also changed
the handling for deferred probe unintentionally. Because of the
looping the second name will now return -ENOENT instead of
-EPROBE_DEFER. Fix the issue by breaking out of the loop if
-EPROBE_DEFER is encountered.

Signed-off-by: Tony Lindgren <tony@atomide.com>
Reviewed-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-06-12 09:57:00 +02:00
Thierry Reding
29a1f2333e gpio: Add helpers for optional GPIOs
Introduce gpiod_get_optional() and gpiod_get_index_optional() helpers
that make it easier for drivers to handle optional GPIOs.

Currently in order to handle optional GPIOs, a driver needs to special
case error handling for -ENOENT, such as this:

	gpio = gpiod_get(dev, "foo");
	if (IS_ERR(gpio)) {
		if (PTR_ERR(gpio) != -ENOENT)
			return PTR_ERR(gpio);

		gpio = NULL;
	}

	if (gpio) {
		/* set up GPIO */
	}

With these new helpers the above is reduced to:

	gpio = gpiod_get_optional(dev, "foo");
	if (IS_ERR(gpio))
		return PTR_ERR(gpio);

	if (gpio) {
		/* set up GPIO */
	}

While at it, device-managed variants of these functions are also
provided.

Signed-off-by: Thierry Reding <treding@nvidia.com>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-05-09 13:48:30 +02:00
Thierry Reding
0879162f33 gpio: Fix gpio_get -> gpiod_get typo in kernel-doc
The function is called gpiod_get(), not gpio_get(). Fix the kernel-doc
comment to match the name.

Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-05-02 15:18:14 -07:00
Thierry Reding
dd34c37aa3 gpio: of: Allow -gpio suffix for property names
Many bindings use the -gpio suffix in property names. Support this in
addition to the -gpios suffix when requesting GPIOs using the new
descriptor-based API.

Signed-off-by: Thierry Reding <treding@nvidia.com>
Acked-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-04-28 12:35:10 -07:00
Thierry Reding
47a95fe716 gpio: of: Remove unneeded dummy function
of_find_gpio() is always called under an IS_ENABLED(CONFIG_OF), so the
dummy implementation provided for !OF configurations is not needed.

Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-04-28 12:35:10 -07:00
Linus Walleij
1333b90f33 gpio: do not set up hardware for IRQ_TYPE_NONE
Some GPIO irqchip drivers exploit the irqdomain mapping
function to set up the IRQ default type in the hardware,
make sure that if we pass IRQ_TYPE_NONE, no hardware setup
whatsoever takes place (this should be the norm) until
later when the IRQ gets utilized.

Cc: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Cc: Santosh Shilimkar <santosh.shilimkar@ti.com>
Cc: linux-omap <linux-omap@vger.kernel.org>
Tested-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Tested-by: Javier Martinez Canillas <javier@dowhile0.org>
Tested-by: Nishanth Menon <nm@ti.com>
Acked-by: Nishanth Menon <nm@ti.com>
Tested-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-04-28 12:35:10 -07:00
Linus Walleij
e45d1c80c0 gpio: put GPIO IRQs into their own lock class
Another feature that is duplicated in a number of GPIO irqchips
is that these cascades IRQs are assigned their own lock class
so as to avoid warnings about lockdep recursions. Do this also
in the generic GPIO irqchip helpers for smooth transition to
this core infrastructure.

Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-04-28 12:35:09 -07:00
Linus Walleij
1c8732bb03 gpio: support threaded interrupts in irqchip helpers
Some off-chip GPIO expanders need to be communicated by I2C or
SPI traffic, but may still support IRQs. By the sleeping nature
of such buses, such IRQ handlers need to be threaded. Support
such handlers in the gpiochip irqchip helpers by flagging IRQs
as threaded if the .can_sleep property of the gpiochip is
true.

Helpfully deny registration of chained IRQ handlers if the
.can_sleep property is set, as such chips will invariably need
a nested handler rather than a chained handler.

Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-04-28 12:35:07 -07:00
Linus Walleij
7633fb959b gpio: set data first, then chip and handler
During irq mapping, in irq_set_chip_and_handler() the process
of setting this up may incur calls to lock the irqchip, which
in turn may need to dereference and use the chip data. So set
the data first, then set the chip and handler.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-04-14 10:22:36 +02:00
Linus Walleij
c3626fdea0 gpio: unmap gpio irqs properly
When using the irqchip helper inside the gpiolib, make sure
the IRQs are unmapped/disposed before the irqdomain is removed
as part of removing the gpiochip.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-03-28 20:42:01 +01:00
Linus Walleij
1425052097 gpio: add IRQ chip helpers in gpiolib
This provides a function gpiochip_irqchip_add() to set
up an irqchip for a GPIO controller, and a function
gpiochip_set_chained_irqchip() to chain it to a parent
irqchip.

Most GPIOs are of the type where a number of lines form
a cascaded interrupt controller chained onto
the primary system interrupt controller (or further down the
chain) so let's add this helper and factor the code to
request the lines to be used as IRQs, the .to_irq() function
and the irqdomain into the core as well.

Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-03-26 10:31:21 +01:00
Alexandre Courbot
23600969ff gpio: clamp returned values to the boolean range
Nothing prevents GPIO drivers from returning values outside the
boolean range, and as it turns out a few drivers are actually doing so.
These values were passed as-is to unsuspecting consumers and created
confusion.

This patch makes the internal _gpiod_get_raw_value() function return a
bool, effectively clamping the GPIO value to the boolean range no
matter what the driver does.

While we are at it, we also change the value parameter of
_gpiod_set_raw_value() to bool type before drivers start doing funny
things with it as well.

Another way to fix this would be to change the prototypes of the driver
interface to use bool directly, but this would require a huge
cross-systems patch so this simpler solution is preferred.

Changes since v1:
- Change local variable type to bool as well, use boolean values in
  code
- Also change prototype of open drain/open source setting functions
  since they are only called from _gpiod_set_raw_value()

This probably calls for a larger booleanization of gpiolib, but let's
keep that for a latter change - right now we need to address the issue
of non-boolean values returned by drivers.

Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-03-14 10:17:03 +01:00
Mika Westerberg
6072b9dcf9 gpio / ACPI: Rework ACPI GPIO event handling
The current ACPI GPIO event handling code was never tested against real
hardware with functioning GPIO triggered events (at the time such hardware
wasn't available). Thus it misses certain things like requesting the GPIOs
properly, passing correct flags to the interrupt handler and so on.

This patch reworks ACPI GPIO event handling so that we:

 1) Use struct acpi_gpio_event for all GPIO signaled events.
 2) Switch to use GPIO descriptor API and request GPIOs by calling
    gpiochip_request_own_desc() that we added in a previous patch.
 3) Pass proper flags from ACPI GPIO resource to request_threaded_irq().

Also instead of open-coding the _AEI iteration loop we can use
acpi_walk_resources(). This simplifies the code a bit and fixes memory leak
that was caused by missing kfree() for buffer returned by
acpi_get_event_resources().

Since the remove path now calls gpiochip_free_own_desc() which takes GPIO
spinlock we need to call acpi_gpiochip_remove() outside of that lock
(analogous to acpi_gpiochip_add() path where the lock is released before
those funtions are called).

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-03-13 15:15:43 +01:00
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
Linus Walleij
f438acdf3d gpio: remove misleading documentation
It is currently debated where the functions to lock a certain
GPIO line as used for IRQs should be called. Delete all
misleading documentation.

Reported-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Jean-Jacques Hiblot <jjhiblot@traphandler.com>
Acked-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-03-07 11:56:45 +08:00
Alexandre Courbot
bb1e88ccb7 gpiolib: add gpiochip_get_desc() driver function
Some drivers dealing with a gpio_chip might need to act on its
descriptors directly; one example is pinctrl drivers that need to lock a
GPIO for being used as IRQ using gpiod_lock_as_irq().

This patch exports a gpiochip_get_desc() function that returns the
GPIO descriptor at the requested index. It also sweeps the
gpio_to_chip() function out of the consumer interface since any holder
of a gpio_chip reference can manipulate its GPIOs way beyond what a
consumer should be allowed to do.

As a result, gpio_chip is not visible anymore to simple GPIO consumers.

Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Jean-Jacques Hiblot <jjhiblot@traphandler.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-02-12 17:11:35 +01:00
Rahul Bedarkar
90df4fe07f GPIO: gpiolib: correct description of gpiod_direction_output
Signed-off-by: Rahul Bedarkar <rahulbedarkar89@gmail.com>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-02-12 17:08:30 +01:00
Philipp Zabel
ef70bbe1aa gpio: make gpiod_direction_output take a logical value
The documentation was not clear about whether
gpio_direction_output should take a logical value or the physical
level on the output line, i.e. whether the ACTIVE_LOW status
would be taken into account.

This converts gpiod_direction_output to use the logical level
and adds a new gpiod_direction_output_raw for the raw value.

Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-02-07 09:47:02 +01:00
Linus Torvalds
8e50966072 GPIO tree bulk changes for v3.14
A big set this merge window, as we have much going on in
 this subsystem. Major changes this time:
 
 - Some core improvements and cleanups to the new GPIO
   descriptor API. This seems to be working now so we can
   start the exodus to this API, moving gradually away from
   the global GPIO numberspace.
 
 - Incremental improvements to the ACPI GPIO core, and move
   the few GPIO ACPI clients we have to the GPIO descriptor
   API right *now* before we go any further. We actually
   managed to contain this *before* we started to litter
   the kernel with yet another hackish global numberspace for
   the ACPI GPIOs, which is a big win.
 
 - The RFkill GPIO driver and all platforms using it have
   been migrated to use the GPIO descriptors rather than
   fixed number assignments. Tegra machine has been migrated
   as part of this.
 
 - New drivers for MOXA ART, Xtensa GPIO32 and SMSC SCH311x.
   Those should be really good examples of how I expect a
   nice GPIO driver to look these days.
 
 - Do away with custom GPIO implementations on a major
   part of the ARM machines: ks8695, lpc32xx, mv78xx0.
   Make a first step towards the same in the horribly
   convoluted Samsung S3C include forest. We expect to
   continue to clean this up as we move forward.
 
 - Flag GPIO lines used for IRQ on adnp, bcm-kona, em,
   intel-mid and lynxpoint.
   This makes the GPIOlib core aware that a certain GPIO line
   is used for IRQs and can then enforce some semantics such
   as disallowing a GPIO line marked as in use for IRQ to be
   switched to output mode.
 
 - Drop all use of irq_set_chip_and_handler_name().
   The name provided in these cases were just unhelpful
   tags like "mux" or "demux".
 
 - Extend the MCP23s08 driver to handle interrupts.
 
 - Minor incremental improvements for rcar, lynxpoint, em
   74x164 and msm drivers.
 
 - Some non-urgent bug fixes here and there, duplicate
   #includes and that usual kind of cleanups.
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Merge tag 'gpio-v3.14-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio

Pull GPIO tree bulk changes from Linus Walleij:
 "A big set this merge window, as we have much going on in this
  subsystem.  The changes to other subsystems (notably a slew of ARM
  machines as I am doing away with their custom APIs) have all been
  ACKed to the extent possible.

  Major changes this time:

   - Some core improvements and cleanups to the new GPIO descriptor API.
     This seems to be working now so we can start the exodus to this
     API, moving gradually away from the global GPIO numberspace.

   - Incremental improvements to the ACPI GPIO core, and move the few
     GPIO ACPI clients we have to the GPIO descriptor API right *now*
     before we go any further.  We actually managed to contain this
     *before* we started to litter the kernel with yet another hackish
     global numberspace for the ACPI GPIOs, which is a big win.

   - The RFkill GPIO driver and all platforms using it have been
     migrated to use the GPIO descriptors rather than fixed number
     assignments.  Tegra machine has been migrated as part of this.

   - New drivers for MOXA ART, Xtensa GPIO32 and SMSC SCH311x.  Those
     should be really good examples of how I expect a nice GPIO driver
     to look these days.

   - Do away with custom GPIO implementations on a major part of the ARM
     machines: ks8695, lpc32xx, mv78xx0.  Make a first step towards the
     same in the horribly convoluted Samsung S3C include forest.  We
     expect to continue to clean this up as we move forward.

   - Flag GPIO lines used for IRQ on adnp, bcm-kona, em, intel-mid and
     lynxpoint.

     This makes the GPIOlib core aware that a certain GPIO line is used
     for IRQs and can then enforce some semantics such as disallowing a
     GPIO line marked as in use for IRQ to be switched to output mode.

   - Drop all use of irq_set_chip_and_handler_name().  The name provided
     in these cases were just unhelpful tags like "mux" or "demux".

   - Extend the MCP23s08 driver to handle interrupts.

   - Minor incremental improvements for rcar, lynxpoint, em 74x164 and
     msm drivers.

   - Some non-urgent bug fixes here and there, duplicate #includes and
     that usual kind of cleanups"

Fix up broken Kconfig file manually to make this all compile.

* tag 'gpio-v3.14-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (71 commits)
  gpio: mcp23s08: fix casting caused build warning
  gpio: mcp23s08: depend on OF_GPIO
  gpio: mcp23s08: Add irq functionality for i2c chips
  ARM: S5P[v210|c100|64x0]: Fix build error
  gpio: pxa: clamp gpio get value to [0,1]
  ARM: s3c24xx: explicit dependency on <plat/gpio-cfg.h>
  ARM: S3C[24|64]xx: move includes back under <mach/> scope
  Documentation / ACPI: update to GPIO descriptor API
  gpio / ACPI: get rid of acpi_gpio.h
  gpio / ACPI: register to ACPI events automatically
  mmc: sdhci-acpi: convert to use GPIO descriptor API
  ARM: s3c24xx: fix build error
  gpio: f7188x: set can_sleep attribute
  gpio: samsung: Update documentation
  gpio: samsung: Remove hardware.h inclusion
  gpio: xtensa: depend on HAVE_XTENSA_GPIO32
  gpio: clps711x: Enable driver compilation with COMPILE_TEST
  gpio: clps711x: Use of_match_ptr()
  net: rfkill: gpio: convert to descriptor-based GPIO interface
  leds: s3c24xx: Fix build failure
  ...
2014-01-21 10:09:12 -08:00
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
Alexandre Courbot
2a3cf6a359 gpiolib: return -ENOENT if no GPIO mapping exists
Some devices drivers make use of optional GPIO parameters. For such
drivers, it is important to discriminate between the case where no
GPIO mapping has been defined for the function they are requesting, and
the case where a mapping exists but an error occured while resolving it
or when acquiring the GPIO.

This patch changes the family of gpiod_get() functions such that they
will return -ENOENT if and only if no GPIO mapping is defined for the
requested function. Other error codes are used when an actual error
occured during the GPIO resolution.

Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Reviewed-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>
2013-12-12 19:33:59 +01:00
Tejun Heo
324a56e16e kernfs: s/sysfs_dirent/kernfs_node/ and rename its friends accordingly
kernfs has just been separated out from sysfs and we're already in
full conflict mode.  Nothing can make the situation any worse.  Let's
take the chance to name things properly.

This patch performs the following renames.

* s/sysfs_elem_dir/kernfs_elem_dir/
* s/sysfs_elem_symlink/kernfs_elem_symlink/
* s/sysfs_elem_attr/kernfs_elem_file/
* s/sysfs_dirent/kernfs_node/
* s/sd/kn/ in kernfs proper
* s/parent_sd/parent/
* s/target_sd/target/
* s/dir_sd/parent/
* s/to_sysfs_dirent()/rb_to_kn()/
* misc renames of local vars when they conflict with the above

Because md, mic and gpio dig into sysfs details, this patch ends up
modifying them.  All are sysfs_dirent renames and trivial.  While we
can avoid these by introducing a dummy wrapping struct sysfs_dirent
around kernfs_node, given the limited usage outside kernfs and sysfs
proper, I don't think such workaround is called for.

This patch is strictly rename only and doesn't introduce any
functional difference.

- mic / gpio renames were missing.  Spotted by kbuild test robot.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Neil Brown <neilb@suse.de>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Ashutosh Dixit <ashutosh.dixit@intel.com>
Cc: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-12-11 15:28:36 -08:00
Andy Shevchenko
fdd6a5fe89 gpiolib: update inline documentation of gpiod_get_index()
The patch just accents that @dev could be NULL.

There is no functional change.

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>
2013-12-09 14:19:27 +01:00
Andy Shevchenko
1a2a99c69e gpiolib: introduce chip_* to print with chip->label prefix
In several places we are printing messages with prefix based on chip->label.
Introduced macros help us to do this easier and in uniform way.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2013-12-09 14:17:21 +01:00
Andy Shevchenko
7589e59fc0 gpiolib: unify pr_* messages format
This patch includes the following amendments:
 1) use "?" as a label when the last one is not defined in gpiod_*;
 2) whenever it's possible gpiod_* are used;
 3) print a function name, if it's already used in other messages.

Additionally it fixes an indentation in few places.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Alexandre Courbot <acourbot@nvidia.com>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2013-12-09 14:14:26 +01:00
Alexandre Courbot
ad824783fb gpio: better lookup method for platform GPIOs
Change the format of the platform GPIO lookup tables to make them less
confusing and improve lookup efficiency.

The previous format was a single linked-list that required to compare
the device name and function ID of every single GPIO defined for each
lookup. Switch that to a list of per-device tables, so that the lookup
can be done in two steps, omitting the GPIOs that are not relevant for a
particular device.

The matching rules are now defined as follows:
- The device name must match *exactly*, and can be NULL for GPIOs not
  assigned to a particular device,
- If the function ID in the lookup table is NULL, the con_id argument of
  gpiod_get() will not be used for lookup. However, if it is defined, it
  must match exactly.
- The index must always match.

Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Acked-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>
2013-12-09 14:05:51 +01:00
Linus Walleij
bdc54ef45d Linux 3.13-rc3
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Merge tag 'v3.13-rc3' into devel

Linux 3.13-rc3
2013-12-09 14:04:37 +01:00
Linus Walleij
9fb1f39eb2 gpio/pinctrl: make gpio_chip members typed boolean
This switches the two members of struct gpio_chip that were
defined as unsigned foo:1 to bool, because that is indeed what
they are. Switch all users in the gpio and pinctrl subsystems
to assign these values with true/false instead of 0/1. The
users outside these subsystems will survive since true/false
is 1/0, atleast we set some kind of more strict typing example.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2013-12-04 14:42:46 +01:00
Alexandre Courbot
b7d0a28a9f gpio: rewrite gpiochip_offset_to_desc()
gpiochip_offset_to_desc() was using gpio_to_desc(), which directly
addresses the global GPIO array we are hoping to get rid of someday.
Reimplement it using the descriptor array of the chip itself, after
checking the requested offset is within the valid bounds of the chip.

Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2013-12-04 13:45:29 +01:00
Heikki Krogerus
351cfe0fe8 gpiolib: change a warning to debug message when failing to get gpio
It's the drivers responsibility to react on failure to get
the gpio descriptors and not the frameworks. Since there are
some common peripherals that may or may not have certain
pins connected to gpio lines, depending on the platform,
printing the warning there may end up generating useless bug
reports.

Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2013-12-03 13:10:48 +01:00
Alexandre Courbot
35c5d7fdc4 gpiolib: use platform GPIO mappings as fallback
For platforms that use device tree or ACPI as the standard way to look
GPIOs up, allow the platform-defined GPIO mappings to be used as a
fallback. This may be useful for platforms that need extra GPIOs mappings
not defined by the firmware.

Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2013-12-03 13:10:48 +01:00
Alexandre Courbot
7cc67b9c74 gpiolib: fix lookup of platform-mapped GPIOs
A typo resulted in GPIO lookup failing unconditionally.

Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Reported-by: Stephen Warren <swarren@wwwdotorg.org>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2013-12-03 13:10:48 +01:00
Alexandre Courbot
209e64f9ed gpiolib: fix of_find_gpio() when OF not defined
The prototype for static GPIO lookup functions has been updated to use
an explicit type for GPIO lookup flags. Unfortunately the definition of
of_find_gpio() when CONFIG_OF is not defined has been omitted, which
triggers a warning. This patch fixes this.

Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2013-11-25 09:03:13 +01:00
Michal Nazarewicz
61c6375d55 gpio: fix memory leak in error path
Signed-off-by: Michal Nazarewicz <mina86@mina86.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2013-11-25 09:03:13 +01:00
Alexandre Courbot
53e7cac35d gpiolib: use dedicated flags for GPIO properties
GPIO mapping properties were defined using the GPIOF_* flags, which are
declared in linux/gpio.h. This file is not included when using the
GPIO descriptor interface.

This patch declares the flags that can be used as GPIO mappings
properties in linux/gpio/driver.h, and uses them in gpiolib, so that no
deprecated declarations are used by the GPIO descriptor interface.

This patch also allows GPIO_OPEN_DRAIN and GPIO_OPEN_SOURCE to be
specified as GPIO mapping properties.

Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2013-11-25 09:03:12 +01:00
Alexandre Courbot
79697ef94c gpiolib: fix find_chip_by_name()
find_chip_by_name() was incorrectly implemented by using
gpio_lookup_list instead of gpiod_chips to iterate through all the
registered GPIO controllers. This patch reimplements it by using
gpiochip_find() with a custom search function, which simplifies the code
on top of fixing the mistake.

Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2013-11-25 09:02:30 +01:00
Rafael J. Wysocki
7b1998116b ACPI / driver core: Store an ACPI device pointer in struct acpi_dev_node
Modify struct acpi_dev_node to contain a pointer to struct acpi_device
associated with the given device object (that is, its ACPI companion
device) instead of an ACPI handle corresponding to it.  Introduce two
new macros for manipulating that pointer in a CONFIG_ACPI-safe way,
ACPI_COMPANION() and ACPI_COMPANION_SET(), and rework the
ACPI_HANDLE() macro to take the above changes into account.
Drop the ACPI_HANDLE_SET() macro entirely and rework its users to
use ACPI_COMPANION_SET() instead.  For some of them who used to
pass the result of acpi_get_child() directly to ACPI_HANDLE_SET()
introduce a helper routine acpi_preset_companion() doing an
equivalent thing.

The main motivation for doing this is that there are things
represented by struct acpi_device objects that don't have valid
ACPI handles (so called fixed ACPI hardware features, such as
power and sleep buttons) and we would like to create platform
device objects for them and "glue" them to their ACPI companions
in the usual way (which currently is impossible due to the
lack of valid ACPI handles).  However, there are more reasons
why it may be useful.

First, struct acpi_device pointers allow of much better type checking
than void pointers which are ACPI handles, so it should be more
difficult to write buggy code using modified struct acpi_dev_node
and the new macros.  Second, the change should help to reduce (over
time) the number of places in which the result of ACPI_HANDLE() is
passed to acpi_bus_get_device() in order to obtain a pointer to the
struct acpi_device associated with the given "physical" device,
because now that pointer is returned by ACPI_COMPANION() directly.
Finally, the change should make it easier to write generic code that
will build both for CONFIG_ACPI set and unset without adding explicit
compiler directives to it.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com> # on Haswell
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Aaron Lu <aaron.lu@intel.com> # for ATA and SDIO part
2013-11-14 23:14:43 +01:00
Linus Torvalds
c2d3306991 GPIO bulk changes for the v3.13 development cycle
- Merged the GPIO descriptor API from Alexandre Courbot.
   This is a first step toward trying to get rid of the
   global GPIO numberspace for the future.
 
 - Add an API so that driver can flag that a certain GPIO
   line is being used by a irqchip backend for generating
   IRQs, so that we can enforce checks, like not allowing
   users to switch that line to an output at runtime, since
   this makes no sense. Implemented corresponding calls
   in a few select drivers.
 
 - ACPI GPIO cleanups, refactorings and switch to using the
   descriptor-based interface.
 
 - Support for the TPS80036 Palmas GPIO variant.
 
 - A new driver for the Broadcom Kona GPIO SoC IP block.
 
 - Device tree support for the PCF857x driver.
 
 - A set of ARM GPIO refactorings with the goal of getting
   rid of a bunch of custom GPIO implementations from the
   arch/arm/* tree:
 
   - Move the IOP GPIO driver to the GPIO subsystem and
     fix all users to use the gpiolib API for accessing
     GPIOs. Delete the old custom GPIO implementation.
 
   - Delete the unused custom PXA GPIO implemention.
 
   - Convert all users of the IXP4 custom GPIO
     implementation to use gpiolib and delete the custom
     implementation.
 
   - Delete the custom Gemini GPIO implementation, also
     completely unused.
 
 - Various cleanups and renamings.
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Merge tag 'gpio-v3.13-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio

Pull GPIO changes from Linus Walleij:
 "Here is the bulk of GPIO changes for the v3.13 development cycle.

  I've got ACKs for the things that affect other subsystems (or it's my
  own subsystem, like pinctrl).  Most of that pertain to an attempt from
  my side to consolidate and get rid of custom GPIO implementations in
  the ARM tree.  I will continue doing this.

  The main change this time is the new GPIO descriptor API, background
  for this can be found in Corbet's summary from this january in LWN:

    http://lwn.net/Articles/533632/

  Summary:

   - Merged the GPIO descriptor API from Alexandre Courbot.  This is a
     first step toward trying to get rid of the global GPIO numberspace
     for the future.

   - Add an API so that driver can flag that a certain GPIO line is
     being used by a irqchip backend for generating IRQs, so that we can
     enforce checks, like not allowing users to switch that line to an
     output at runtime, since this makes no sense.  Implemented
     corresponding calls in a few select drivers.

   - ACPI GPIO cleanups, refactorings and switch to using the
     descriptor-based interface.

   - Support for the TPS80036 Palmas GPIO variant.

   - A new driver for the Broadcom Kona GPIO SoC IP block.

   - Device tree support for the PCF857x driver.

   - A set of ARM GPIO refactorings with the goal of getting rid of a
     bunch of custom GPIO implementations from the arch/arm/* tree:

     * Move the IOP GPIO driver to the GPIO subsystem and fix all users
       to use the gpiolib API for accessing GPIOs.  Delete the old
       custom GPIO implementation.

     * Delete the unused custom PXA GPIO implemention.

     * Convert all users of the IXP4 custom GPIO implementation to use
       gpiolib and delete the custom implementation.

     * Delete the custom Gemini GPIO implementation, also completely
       unused.

   - Various cleanups and renamings"

* tag 'gpio-v3.13-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (85 commits)
  gpio: gpio-mxs: Remove unneeded dt checks
  gpio: pl061: don't depend on CONFIG_ARM
  gpio: bcm-kona: add missing .owner to struct gpio_chip
  gpiolib: provide a declaration of seq_file in gpio/driver.h
  gpiolib: include gpio/consumer.h in of_gpio.h for desc_to_gpio()
  gpio: provide stubs for devres gpio functions
  gpiolib: devres: add missing headers
  gpiolib: make GPIO_DEVRES depend on GPIOLIB
  gpiolib: devres: fix devm_gpiod_get_index()
  gpiolib / ACPI: document the GPIO descriptor based interface
  gpiolib / ACPI: allow passing GPIOF_ACTIVE_LOW for GpioInt resources
  gpiolib / ACPI: add ACPI support for gpiod_get_index()
  gpiolib / ACPI: convert to gpiod interfaces
  gpiolib: add gpiod_get() and gpiod_put() functions
  gpiolib: port of_ functions to use gpiod
  gpiolib: export descriptor-based GPIO interface
  Fixup "MAINTAINERS: GPIO-INTEL-MID: add maintainer"
  gpio: bcm281xx: Don't print addresses of GPIO area in probe()
  gpio: tegra: use new gpio_lock_as_irq() API
  gpio: rcar: Include linux/of.h header
  ...
2013-11-12 15:50:46 +09:00
Linus Torvalds
8a5dc585d5 Main pin control pull request for the v3.13 cycle:
- Blackfin ADI pin control driver, we move yet another
   architecture under this subsystem umbrella.
 
 - Incremental updates to the Renesas Super-H PFC pin control
   driver. New subdriver for the r8a7791 SoC.
 
 - Non-linear GPIO ranges from the gpiolib side of things,
   this enabled simplified device tree bindings by referring
   entire groups of pins on some pin controller to act as
   back-end for a certain GPIO-chip driver.
 
 - Add the Abilis TB10x pin control driver used on the ARC
   architecture. Also the corresponding GPIO driver is merged
   through this tree, so the ARC has full support for pins
   and GPIOs after this.
 
 - Subdrivers for Freescale i.MX1, i.MX27 and i.MX50 pin
   controller instances. The i.MX1 and i.MX27 is an entirely
   new family (silicon) of controllers whereas i.MX50 is
   a variant of the previous supported controller.
 
 - Then the usual slew of fixes, cleanups and incremental
   updates.
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Merge tag 'pinctrl-for-v3.13-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl

Pull pin control updates from Linus Walleij:
 "Main pin control pull request for the v3.13 cycle.

  The changes hitting arch/blackfin are ACKed by the Blackfin
  maintainer, and the device tree bindings are ACKed to the extent
  possible by someone from the device tree maintainers group.

   - Blackfin ADI pin control driver, we move yet another architecture
     under this subsystem umbrella.

   - Incremental updates to the Renesas Super-H PFC pin control driver.
     New subdriver for the r8a7791 SoC.

   - Non-linear GPIO ranges from the gpiolib side of things, this
     enabled simplified device tree bindings by referring entire groups
     of pins on some pin controller to act as back-end for a certain
     GPIO-chip driver.

   - Add the Abilis TB10x pin control driver used on the ARC
     architecture.  Also the corresponding GPIO driver is merged through
     this tree, so the ARC has full support for pins and GPIOs after
     this.

   - Subdrivers for Freescale i.MX1, i.MX27 and i.MX50 pin controller
     instances.  The i.MX1 and i.MX27 is an entirely new family
     (silicon) of controllers whereas i.MX50 is a variant of the
     previous supported controller.

   - Then the usual slew of fixes, cleanups and incremental updates"

The ARC DT changes are apparently still pending, that hopefully gets
sorted out in a timely manner.

* tag 'pinctrl-for-v3.13-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl: (48 commits)
  pinctrl: imx50: add pinctrl support code for the IMX50 SoC
  pinctrl: at91: copy define to driver
  pinctrl: remove minor dead code
  pinctrl: imx: fix using pin->input_val wrongly
  pinctrl: imx1: fix return value check in imx1_pinctrl_core_probe()
  gpio: tb10x: fix return value check in tb10x_gpio_probe()
  gpio: tb10x: use module_platform_driver to simplify the code
  pinctrl: imx27: imx27 pincontrol driver
  pinctrl: imx1 core driver
  pinctrl: sh-pfc: r8a7791 PFC support
  sh-pfc: r8a7778: Add CAN pin groups
  gpio: add TB10x GPIO driver
  pinctrl: at91: correct a few typos
  pinctrl: mvebu: remove redundant of_match_ptr
  pinctrl: tb10x: use module_platform_driver to simplify the code
  pinctrl: tb10x: fix the error handling in tb10x_pinctrl_probe()
  pinctrl: add documentation for pinctrl_get_group_pins()
  pinctrl: rockchip: emulate both edge triggered interrupts
  pinctrl: rockchip: add rk3188 specifics
  pinctrl: rockchip: remove redundant check
  ...
2013-11-12 15:40:03 +09:00
Mika Westerberg
e01f440a68 gpiolib / ACPI: allow passing GPIOF_ACTIVE_LOW for GpioInt resources
The ACPI GpioInt resources contain polarity field that is used to specify
whether the interrupt is active high or low. Since gpiolib supports
GPIOF_ACTIVE_LOW we can pass this information in the flags field in
acpi_find_gpio(), analogous to the DeviceTree version.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2013-10-19 23:32:14 +02:00
Mika Westerberg
81f59e9d13 gpiolib / ACPI: add ACPI support for gpiod_get_index()
gpiod_get_index() and gpiod_get() are now the new preferred way to request
GPIOs. Add support for finding the corresponding GPIO descriptor from ACPI
namespace.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2013-10-19 23:31:37 +02:00
Alexandre Courbot
bae48da237 gpiolib: add gpiod_get() and gpiod_put() functions
Add gpiod_get(), gpiod_get_index() and gpiod_put() functions that
provide safer management of GPIOs.

These functions put the GPIO framework in line with the conventions of
other frameworks in the kernel, and help ensure every GPIO is declared
properly and valid while it is used.

Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2013-10-19 23:24:56 +02:00
Alexandre Courbot
79a9becda8 gpiolib: export descriptor-based GPIO interface
This patch exports the gpiod_* family of API functions, a safer
alternative to the legacy GPIO interface. Differences between the gpiod
and legacy gpio APIs are:

- gpio works with integers, whereas gpiod operates on opaque handlers
  which cannot be forged or used before proper acquisition
- gpiod get/set functions are aware of the active low state of a GPIO
- gpio consumers should now include <linux/gpio/consumer.h> to access
  the new interface, whereas chips drivers will use
  <linux/gpio/driver.h>

The legacy gpio API is now built as inline functions on top of gpiod.

Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2013-10-19 23:24:45 +02:00
Linus Walleij
b41fb43911 Linux 3.12-rc6
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Merge tag 'v3.12-rc6' into devel

Linux 3.12-rc6

Conflicts:
	drivers/gpio/gpio-lynxpoint.c
2013-10-19 23:24:03 +02:00
Greg Kroah-Hartman
a7204d72db Merge 3.12-rc6 into driver-core-next
We want these fixes here too.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-19 13:05:38 -07:00
Christian Ruppert
586a87e6ed pinctrl/gpio: non-linear GPIO ranges accesible from gpiolib
This patch adds the infrastructure required to register non-linear gpio
ranges through gpiolib and the standard GPIO device tree bindings.

Signed-off-by: Christian Ruppert <christian.ruppert@abilis.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2013-10-16 15:33:50 +02:00
Linus Walleij
d468bf9eca gpio: add API to be strict about GPIO IRQ usage
It is currently often possible in many GPIO drivers to request
a GPIO line to be used as IRQ after calling gpio_to_irq() and,
as the gpiolib is not aware of this, set the same line to
output and start driving it, with undesired side effects.

As it is a bogus usage scenario to request a line flagged as
output to used as IRQ, we introduce APIs to let gpiolib track
the use of a line as IRQ, and also set this flag from the
userspace ABI.

The API is symmetric so that lines can also be flagged from
.irq_enable() and unflagged from IRQ by .irq_disable().
The debugfs file is altered so that we see if a line is
reserved for IRQ.

Cc: Enric Balletbo i Serra <eballetbo@gmail.com>
Cc: Grant Likely <grant.likely@linaro.org>
Cc: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Cc: Santosh Shilimkar <santosh.shilimkar@ti.com>
Acked-by: Alexandre Courbot <acourbot@nvidia.com>
Reviewed-by: Stephen Warren <swarren@nvidia.com>
Reviewed-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2013-10-16 09:59:54 +02:00
Alexandre Courbot
0204df470d gpiolib: let gpiod_request() return -EPROBE_DEFER
Patch be1a4b brought some improvements to the GPIO error handling code,
but also changed the return value of gpiod_request() when called on a
not yet initialized GPIO descriptor: it now returns -EINVAL instead of
-EPROBE_DEFER, and this affects some drivers.

This patch restores the original behavior for gpiod_request(). It is
safe to do so now that desc_to_gpio() does not rely on the GPIO
descriptor to be initialized. Other functions changed by patch be1a4b
do not see their return value affected, so these are not reverted.

Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Reported-by: Dr. H. Nikolaus Schaller <hns@goldelico.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2013-10-11 16:31:54 +02:00
Alexandre Courbot
8c0fca8153 gpiolib: safer implementation of desc_to_gpio()
The current implementation of desc_to_gpio() relies on the chip pointer
to be set to a valid value in order to compute the GPIO number. This
was done in the hope that we can get rid of the gpio_desc global array,
but this is not happening anytime soon.

This patch reimplements desc_to_gpio() in a fashion similar to that of
gpio_to_desc(). As a result, desc_to_gpio(gpio_to_desc(gpio)) == gpio is
now always true. This allows to call desc_to_gpio() on non-initialized
descriptors as some error-handling code currently does.

Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Reported-by: Dr. H. Nikolaus Schaller <hns@goldelico.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2013-10-11 16:31:53 +02:00
Tejun Heo
388975ccca sysfs: clean up sysfs_get_dirent()
The pre-existing sysfs interfaces which take explicit namespace
argument are weird in that they place the optional @ns in front of
@name which is contrary to the established convention.  For example,
we end up forcing vast majority of sysfs_get_dirent() users to do
sysfs_get_dirent(parent, NULL, name), which is silly and error-prone
especially as @ns and @name may be interchanged without causing
compilation warning.

This renames sysfs_get_dirent() to sysfs_get_dirent_ns() and swap the
positions of @name and @ns, and sysfs_get_dirent() is now a wrapper
around sysfs_get_dirent_ns().  This makes confusions a lot less
likely.

There are other interfaces which take @ns before @name.  They'll be
updated by following patches.

This patch doesn't introduce any functional changes.

v2: EXPORT_SYMBOL_GPL() wasn't updated leading to undefined symbol
    error on module builds.  Reported by build test robot.  Fixed.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Kay Sievers <kay@vrfy.org>
Cc: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-09-26 15:33:18 -07:00
Alexandre Courbot
d8e0ac0824 gpiolib: factorize gpiod_get/set functions
gpiod_get/set functions share common code between their regular and
cansleep variants. The exporting of the gpiod interface will make
the situation worse. This patch factorizes the common code to avoid code
redundancy.

Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2013-09-20 10:30:18 +02:00
Mark Brown
7b17b59fea gpiolib: Include GPIO label in log messages for GPIOs
Provide the human readable label for the GPIO as well as the number when
we are recording it in order to improve the readability of log messages.

Signed-off-by: Mark Brown <broonie@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2013-09-19 14:49:17 +02:00
Mark Brown
6424de5af1 gpiolib: Provide helper macros for logging of GPIO events
Currently many but not all GPIO log messages log the GPIO number and the
formats vary. Ensure that this is done consistently by defining logging
helpers which take the GPIO descriptor.

The will help people pattern matching on logs and providing the number
makes the log messages that omitted it more useful.

Signed-off-by: Mark Brown <broonie@linaro.org>
Acked-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2013-09-19 14:48:40 +02:00
Linus Walleij
65d876564e gpio: return -ENOTSUPP if debounce cannot be set
It appears some drivers are using gpio_set_debounce()
opportunistically, i.e. without knowing whether it works or
not. (Example: input/keyboard/gpio_keys.c) to account for
this use case, return -ENOTSUPP and do not print any
warnings in this case.

Took a round over the other gpio_set_debounce() consumers
to make sure that none of them are relying on the returned
error code to be something specific.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2013-09-04 14:22:47 +02:00
Linus Walleij
be1a4b1308 gpio: improve error path in gpiolib
At several places the gpiolib will proceed to handle a GPIO
descriptor even if it's ->chip member is NULL and no gpiochip
is associated.

Fix this by checking that both the descriptor cookie *and*
the chip pointer are valid.

Also bail out earlier with more specific diagnostic messages
on missing operations for setting as input/output or debounce.

ChangeLog v1->v2:
- Also return -EIO on gpiod_set_debounce() with missing
  operations in the vtable
- Fix indentations.

Suggested-by: Alexandre Courbot <acourbot@nvidia.com>
Acked-by: Alexandre Courbot <acourbot@nvidia.com>
Reviewed-by: Frank Rowand <frank.rowand@sonymobile.com>
Cc: Tim Bird <tim.bird@sonymobile.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2013-09-03 14:08:28 +02:00
Jingoo Han
a3d88c92a1 gpiolib: replace strict_strtol() with kstrtol()
The usage of strict_strtol() is not preferred, because
strict_strtol() is obsolete. Thus, kstrtol() should be
used.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2013-07-21 00:20:34 +02:00
Zhangfei Gao
3bae4811fb gpiolib: remove warnning of allocations with IRQs disabled
Move of_gpiochip_add outof spin_lock, since kzalloc inside
of_gpiochip_add -> of_gpiochip_add_pin_range -> gpiochip_add_pin_range -> kzalloc

WARNING: at kernel/lockdep.c:2740 lockdep_trace_alloc+0xf8/0xfc()
DEBUG_LOCKS_WARN_ON(irqs_disabled_flags(flags))

Signed-off-by: Zhangfei Gao <zhangfei.gao@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2013-06-20 10:37:41 +02:00
Alexandre Courbot
24d7628fe8 gpiolib: move comment to right function
This comment applies to gpio_to_chip(), not gpiod_to_chip().

Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2013-03-02 13:20:20 +00:00
Alexandre Courbot
def634338d gpiolib: use const parameters when possible
Constify descriptor parameter of gpiod_* functions for those that
should obviously not modify it. This includes value or direction get,
cansleep, and IRQ number query.

Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2013-03-02 13:20:19 +00:00
Alexandre Courbot
bcabdef12d gpiolib: check descriptors validity before use
Some functions dereferenced their GPIO descriptor argument without
checking its validity first, potentially leading to an oops when given
an invalid argument.

This patch also makes gpio_get_value() more resilient when given an
invalid GPIO, returning 0 instead of silently crashing.

Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Cc: Ryan Mallon <rmallon@gmail.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2013-03-02 13:20:19 +00:00
Tejun Heo
62f516b8d6 gpio: convert to idr_alloc()
Convert to the much saner new idr interface.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Cc: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-27 19:10:15 -08:00
Linus Torvalds
4c8c225abf GPIO changes for Linux 3.9
This branch contains the usual set of individual driver improvements and
 bug fixes, as well as updates to the core code. The more notable changes
 include:
 
 - Internally add new API for referencing GPIOs by gpio_desc instead of
   number. Eventually this will become a public API
 - ACPI GPIO binding support
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Merge tag 'gpio-for-linus' of git://git.secretlab.ca/git/linux

Pull GPIO changes from Grant Likely:
 "This branch contains the usual set of individual driver improvements
  and bug fixes, as well as updates to the core code.  The more notable
  changes include:

   - Internally add new API for referencing GPIOs by gpio_desc instead
     of number.  Eventually this will become a public API

   - ACPI GPIO binding support"

* tag 'gpio-for-linus' of git://git.secretlab.ca/git/linux: (33 commits)
  arm64: select ARCH_WANT_OPTIONAL_GPIOLIB
  gpio: em: Use irq_domain_add_simple() to fix runtime error
  gpio: using common order: let 'static const' instead of 'const static'
  gpio/vt8500: memory cleanup missing
  gpiolib: Fix locking on gpio debugfs files
  gpiolib: let gpio_chip reference its descriptors
  gpiolib: use descriptors internally
  gpiolib: use gpio_chips list in gpiochip_find_base
  gpiolib: use gpio_chips list in sysfs ops
  gpiolib: use gpio_chips list in gpiochip_find
  gpiolib: use gpio_chips list in gpiolib_sysfs_init
  gpiolib: link all gpio_chips using a list
  gpio/langwell: cleanup driver
  gpio/langwell: Add Cloverview ids to pci device table
  gpio/lynxpoint: add chipset gpio driver.
  gpiolib: add missing braces in gpio_direction_show
  gpiolib-acpi: Fix error checks in interrupt requesting
  gpio: mpc8xxx: don't set IRQ_TYPE_NONE when creating irq mapping
  gpiolib: remove gpiochip_reserve()
  arm: pxa: tosa: do not use gpiochip_reserve()
  ...
2013-02-26 09:35:29 -08:00
Grant Likely
362432aed5 gpiolib: Fix locking on gpio debugfs files
The debugfs files really need to hold the gpiolib spinlock before
accessing the list. Otherwise chip addition/removal will cause an oops.

Cc: Alexandre Courbot <acourbot@nvidia.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2013-02-11 22:21:28 +00:00
Alexandre Courbot
6c0b4e6c85 gpiolib: let gpio_chip reference its descriptors
Add a pointer to the gpio_chip structure that references the array of
GPIO descriptors belonging to the chip, and update gpiolib code to use
this pointer instead of the global gpio_desc[] array. This is another
step towards the removal of the gpio_desc[] global array.

Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.orh>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2013-02-11 22:21:28 +00:00
Alexandre Courbot
372e722ea4 gpiolib: use descriptors internally
Make sure gpiolib works internally with descriptors and (chip, offset)
pairs instead of using the global integer namespace. This prepares the
ground for the removal of the global gpio_desc[] array and the
introduction of the descriptor-based GPIO API.

Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
[grant.likely: Squash in fix for link error when CONFIG_SYSFS=n]
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2013-02-11 22:20:55 +00:00
Alexandre Courbot
83cabe33eb gpiolib: use gpio_chips list in gpiochip_find_base
Re-implement gpiochip_find_base using the list of chips instead of the
global gpio_desc[] array. This makes it both simpler and more efficient,
and is needed to remove the global descriptors array.

The new code should preserve the exact same GPIO number assignment
policy as the code it is replacing. There shouldn't be any visible
change to the assigned GPIO numbers.

Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
[grant.likely: Added comment about assignment policy]
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2013-02-09 10:07:10 +00:00
Alexandre Courbot
cb1650d4e0 gpiolib: use gpio_chips list in sysfs ops
This makes the code both simpler and faster compared to parsing the GPIO
number space.

Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2013-02-09 09:30:17 +00:00
Alexandre Courbot
125eef96f6 gpiolib: use gpio_chips list in gpiochip_find
Using the GPIO chips list is much faster than parsing the entire GPIO
number space.

Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2013-02-09 09:23:30 +00:00
Alexandre Courbot
65493e3ac4 gpiolib: use gpio_chips list in gpiolib_sysfs_init
Use the small list of GPIO chips instead of parsing the whole GPIO
number space.

Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2013-02-09 09:22:21 +00:00
Alexandre Courbot
1a989d0f1d gpiolib: link all gpio_chips using a list
Add a list member to gpio_chip that allows all chips to be parsed
quickly. The current method requires parsing the entire GPIO integer
space, which is painfully slow. Using a list makes many chip operations
that involve lookup or parsing faster, and also simplifies the code. It
is also necessary to eventually get rid of the global gpio_desc[] array.

The list of gpio_chips is always ordered by base GPIO number to ensure
chips traversal is done in the right order.

Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2013-02-09 09:20:12 +00:00
Michał Mirosław
9f3b795a62 driver-core: constify data for class_find_device()
All in-kernel users of class_find_device() don't really need mutable
data for match callback.

In two places (kernel/power/suspend_test.c, drivers/scsi/osd/osd_uld.c)
this patch changes match callbacks to use const search data.

The const is propagated to rtc_class_open() and power_supply_get_by_name()
parameters.

Note that there's a dev reference leak in suspend_test.c that's not
touched in this patch.

Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-02-06 12:18:56 -08:00
Alexandre Courbot
476171ce78 gpiolib: add missing braces in gpio_direction_show
Add missing braces in an if..else condition.

Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2013-02-04 21:46:56 +01:00
Alexandre Courbot
710b40eac4 gpiolib: remove gpiochip_reserve()
gpiochip_reserve() has no user and stands in the way of the removal of
the static gpio_desc[] array. Remove this function as well as the now
unneeded RESERVED flag of struct gpio_desc.

Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2013-02-04 21:41:46 +01:00
Linus Torvalds
b0885d01f9 GPIO follow up patch and type change for v3.5 merge window
Primarily device driver additions, features and bug fixes. Not much
 touching gpio common subsystem support. Should not be scary.
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Merge tag 'gpio-for-linus' of git://git.secretlab.ca/git/linux-2.6

Pull GPIO updates from Grant Likely:
 "GPIO follow up patch and type change for v3.5 merge window

  Primarily device driver additions, features and bug fixes.  Not much
  touching gpio common subsystem support.  Should not be scary."

* tag 'gpio-for-linus' of git://git.secretlab.ca/git/linux-2.6: (34 commits)
  gpio: Provide the STMPE GPIO driver with its own IRQ Domain
  gpio: add TS-5500 DIO blocks support
  gpio: pcf857x: use client->irq for gpio_to_irq()
  gpio: stmpe: Add DT support for stmpe gpio
  gpio: pl061 depends on ARM
  gpio/pl061: remove old comment
  gpio: SPEAr: add spi chipselect control driver
  gpio: gpio-max710x: Support device tree probing
  gpio: twl4030: Use only TWL4030_MODULE_LED for LED configuration
  gpio: tegra: read output value when gpio is set in direction_out
  gpio: pca953x: Add compatible strings to gpio-pca953x driver
  gpio: pca953x: Register an IRQ domain
  gpio: mvebu: Set free callback for gpio_chip
  gpio: tegra: Drop exporting static functions
  gpio: tegra: Staticize non-exported symbols
  gpio: tegra: fix suspend/resume apis
  gpio-pch: Set parent dev for gpio chip
  gpio: em: Fix build errors
  GPIO: clps711x: use platform_device_unregister in gpio_clps711x_init()
  gpio/tc3589x: convert to use the simple irqdomain
  ...
2012-12-11 13:00:56 -08:00
Axel Lin
b4d4b1f087 gpiolib: Fix use after free in gpiochip_add_pin_range
This is introduced by commit 9ab6e988
"gpiolib: return any error code from range creation".

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2012-11-21 10:08:05 +01:00
Linus Walleij
316511c013 gpiolib: rename pin range arguments
To be crystal clear on what the arguments mean in this
funtion dealing with both GPIO and PIN ranges with confusing
naming, we now have gpio_offset and pin_offset and we are
on the clear that these are offsets into the specific GPIO
and pin controller respectively. The GPIO chip itself will
of course keep track of the base offset into the global
GPIO number space.

Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2012-11-21 10:07:48 +01:00
Linus Walleij
8f23ca1a73 gpiolib: return any error code from range creation
If we try to create a range for a certain GPIO chip and the
target pin controller is not yet available it may return
a probe deferral error code, so handle this all the way
our by checking the error code.

Reviewed-by: Stephen Warren <swarren@nvidia.com>
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2012-11-21 08:55:11 +01:00
Linus Walleij
192c369c61 gpiolib: rename find_pinctrl_*
Rename the function find_pinctrl_and_add_gpio_range()
to pinctrl_find_and_add_gpio_range() so as to be consistent
with the rest of the functions.

Reviewed-by: Stephen Warren <swarren@nvidia.com>
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2012-11-21 08:55:10 +01:00
Linus Walleij
3f0f867060 gpiolib: let gpiochip_add_pin_range() specify offset
Like with commit 3c739ad0df
it is not always enough to specify all the pins of a gpio_chip
from offset zero to be added to a pin map range, since the
mapping from GPIO to pin controller may not be linear at all,
but need to be broken into a few consecutive sub-ranges or
1-pin entries for complicated cases. The ranges may also be
sparse.

This alters the signature of the function to accept offsets
into both the GPIO-chip local pinspace and the pin controller
local pinspace.

Reviewed-by: Stephen Warren <swarren@nvidia.com>
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2012-11-21 08:55:03 +01:00
Linus Walleij
1e63d7b936 gpiolib: separation of pin concerns
The fact that of_gpiochip_add_pin_range() and
gpiochip_add_pin_range() share too much code is fragile and
will invariably mean that bugs need to be fixed in two places
instead of one.

So separate the concerns of gpiolib.c and gpiolib-of.c and
have the latter call the former as back-end. This is necessary
also when going forward with other device descriptions such
as ACPI.

This is done by:

- Adding a return code to gpiochip_add_pin_range() so we can
  reliably check whether this succeeds.

- Get rid of the custom of_pinctrl_add_gpio_range() from
  pinctrl. Instead create of_pinctrl_get() to just retrive the
  pin controller per se from an OF node. This composite
  function was just begging to be deleted, it was way to
  purpose-specific.

- Use pinctrl_dev_get_name() to get the name of the retrieved
  pin controller and use that to call back into the generic
  gpiochip_add_pin_range().

Now the pin range is only allocated and tied to a pin
controller from the core implementation in gpiolib.c.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2012-11-11 19:06:07 +01:00
Linus Walleij
9ef0d6f762 gpiolib: call pin removal in chip removal function
This makes us call gpiochio_remove_pin_ranges() in the
gpiochip_remove() function, so we get rid of ranges when
freeing the chip.

Reviewed-by: Stephen Warren <swarren@nvidia.com>
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2012-11-11 19:06:06 +01:00
Linus Walleij
165adc9c17 gpiolib: fix up function prototypes etc
Commit 69e1601bca88809dc118abd1becb02c15a02ec71
"gpiolib: provide provision to register pin ranges"

Got most of it's function prototypes wrong, so fix this up by:

- Moving the void declarations into static inlines in
  <linux/gpio.h> (previously the actual prototypes were declared
  here...)

- Declare the gpiochip_add_pin_range() and
  gpiochip_remove_pin_ranges() functions in <asm-generic/gpio.h>
  together with the pin range struct declaration itself.

- Actually only implement these very functions in gpiolib.c
  if CONFIG_PINCTRL is set.

- Additionally export the symbols since modules will need to
  be able to do this.

Reviewed-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2012-11-11 19:06:04 +01:00
Shiraz Hashim
f23f1516b6 gpiolib: provide provision to register pin ranges
pinctrl subsystem needs gpio chip base to prepare set of gpio
pin ranges, which a given pinctrl driver can handle. This is
important to handle pinctrl gpio request calls in order to
program a given pin properly for gpio operation.

As gpio base is allocated dynamically during gpiochip
registration, presently there exists no clean way to pass this
information to the pinctrl subsystem.

After few discussions from [1], it was concluded that may be
gpio controller reporting the pin range it supports, is a
better way than pinctrl subsystem directly registering it.

[1] http://comments.gmane.org/gmane.linux.ports.arm.kernel/184816

Cc: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Shiraz Hashim <shiraz.hashim@st.com>
[Edited documentation a bit]
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2012-11-11 19:06:00 +01:00
Dan Carpenter
529f2ad5e3 gpiolib: unlock on error in gpio_export()
We need to unlock here before returning.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2012-10-26 09:35:17 +02:00
Mathias Nyman
ad2fab36d7 gpiolib: Don't return -EPROBE_DEFER to sysfs, or for invalid gpios
gpios requested with invalid numbers, or gpios requested from userspace via sysfs
should not try to be deferred on failure.

Cc: stable@kernel.org
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2012-10-26 09:25:10 +02:00
Mathias Nyman
80b0a60292 gpiolib: add gpio get direction callback support
Add .get_direction callback to gpio_chip. This allows gpiolib
to check the current direction of a gpio.
Used to show the correct gpio direction in sysfs and debug entries.

If callback is not set then gpiolib will work as previously;
e.g. guessing everything is input until a direction is set.

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2012-10-26 09:18:55 +02:00
Ryan Mallon
fc4e251499 gpiolib: Refactor gpio_export
The gpio_export function uses nested if statements and the status
variable to handle the failure cases. This makes the function logic
difficult to follow. Refactor the code to abort immediately on failure
using goto. This makes the code slightly longer, but significantly
reduces the nesting and number of split lines and makes the code easier
to read.

Signed-off-by: Ryan Mallon <rmallon@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2012-10-23 00:13:36 +02:00
Thierry Reding
f9c4a31f61 gpiolib: Use seq_file's iterator interface
When dumping a collection of items via seq_file, it is recommended to
use the iterator interface. For the gpiolib debugfs interface this can
be done to dump each GPIO chip in turn.

Note that for gpiolib this is a little cumbersome because it does not
provide a list of registered GPIO chips and the only way to iterate is
over each GPIO individually. Once a chip is found, the number of GPIOs
it provides can be skipped as a small optimization.

This patch was requested by Arnd Bergmann here:

	http://article.gmane.org/gmane.linux.ports.tegra/3535

Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
Cc: Linus Walleij <linus.walleij@stericsson.com>
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: linux-kernel@vger.kernel.org
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2012-08-17 07:35:41 +02:00
Mark Brown
e935457630 gpiolib: Defer failed gpio requests by default
Since users must be explicitly provided with a GPIO number in order to
request one the overwhelmingly common case for failing to request will
be that the required GPIO driver has not yet registered and we should
therefore defer until it has registered.

In order to avoid having to code this logic in individual drivers have
gpio_request() return -EPROBE_DEFER when failing to look up the GPIO.
Drivers which don't want this behaviour can override it if they desire.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2012-07-17 21:00:20 +02:00
Grant Likely
07ce8ec730 gpiolib: Remove 'const' from data argument of gpiochip_find()
Commit 3d0f7cf0 "gpio: Adjust of_xlate API to support multiple GPIO
chips" changed the api of gpiochip_find to drop const from the data
parameter of the match hook, but didn't also drop const from data
causing a build warning.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2012-05-18 23:01:05 -06:00
H Hartley Sweeten
ee1c1e7d64 gpiolib: quiet gpiochip_add boot message noise
The pr_info message in gpiochip_add gets displayed for every
gpiochip registered. When first bringing up a system this
information could be helpful but for normal use it's just a
bunch of noise. Change the message to a pr_debug.

Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2012-05-18 22:12:50 -06:00
Grant Likely
3d0f7cf0f3 gpio: Adjust of_xlate API to support multiple GPIO chips
This patch changes the of_xlate API to make it possible for multiple
gpio_chips to refer to the same device tree node.  This is useful for
banked GPIO controllers that use multiple gpio_chips for a single
device.  With this change the core code will try calling of_xlate on
each gpio_chip that references the device_node and will return the
gpio number for the first one to return 'true'.

Tested-by: Roland Stigge <stigge@antcom.de>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2012-05-18 16:48:36 -06:00
Wolfram Sang
fc3a1f04f5 gpio: add flags to export GPIOs when requesting
Introduce new flags to automatically export GPIOs when using the convenience
functions gpio_request_one() or gpio_request_array(). This eases support for
custom boards where lots of GPIOs need to be exported for customer
applications.

Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2012-04-05 21:24:06 -07:00
Mark Brown
e4e449e828 gpiolib: Add comments explaining the _cansleep() WARN_ON()s
I've seen users getting very confused by the WARN_ON()s for can_sleep
GPIOs in the atomic-safe paths, the discoverability of the non-atomic
version of the API seems to be hampered by the fact that it's defined
in a header file not the .c file where the warnings are.

Add a couple of comments next to the warnings to help people on their
way.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Reviwed-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2012-03-05 08:05:08 -07:00
Laxman Dewangan
25553ff075 gpio: gpiolib: Support for open source/emitter gpios
Adding support for the open source gpio on which client
can specify the open source property through GPIO flag
GPIOF_OPEN_SOURCE at the time of gpio request.
The open source pins are normally pulled low and it
cannot be driven to output with value of 0 and so
when client request for setting the pin to LOW, the
gpio will be set to input direction to make pin in tristate
and hence PULL-DOWN on pins will make the state to LOW.
The open source pin can be driven to HIGH by setting output
with value of 1.

Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Reviwed-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2012-03-05 07:49:44 -07:00
Laxman Dewangan
aca5ce14eb gpio: gpiolib: Support for open drain/collector gpios
Adding support for the open drain gpio on which client
can specify the open drain property through GPIO flag
GPIOF_OPEN_DRAIN at the time of gpio request.
The open drain pins are normally pulled high and it
cannot be driven to output with value of 1 and so
when client request for setting the pin to HIGH, the
gpio will be set to input direction to make pin in tristate
and hence PULL-UP on pins will make the state to HIGH.
The open drain pin can be driven to LOW by setting output
with value of 0.

Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Reviwed-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2012-03-05 07:49:44 -07:00
Grant Likely
6e2cf65140 gpio: constify the data parameter to gpiochip_find()
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2012-03-02 15:56:03 -07:00
Ming Lei
864533ceb6 Fix circular locking dependency (3.3-rc2)
Hi,

On Wed, Feb 8, 2012 at 8:41 PM, Felipe Balbi <balbi@ti.com> wrote:
> Hi guys,
>
> I have just triggered the folllowing:
>
> [   84.860321] ======================================================
> [   84.860321] [ INFO: possible circular locking dependency detected ]
> [   84.860321] 3.3.0-rc2-00026-ge4e8a39 #474 Not tainted
> [   84.860321] -------------------------------------------------------
> [   84.860321] bash/949 is trying to acquire lock:
> [   84.860321]  (sysfs_lock){+.+.+.}, at: [<c0275358>] gpio_value_store+0x24/0xcc
> [   84.860321]
> [   84.860321] but task is already holding lock:
> [   84.860321]  (s_active#22){++++.+}, at: [<c016996c>] sysfs_write_file+0xdc/0x184
> [   84.911468]
> [   84.911468] which lock already depends on the new lock.
> [   84.911468]
> [   84.920043]
> [   84.920043] the existing dependency chain (in reverse order) is:
> [   84.920043]
> [   84.927886] -> #1 (s_active#22){++++.+}:
> [   84.927886]        [<c008f640>] check_prevs_add+0xdc/0x150
> [   84.927886]        [<c008fc18>] validate_chain.clone.24+0x564/0x694
> [   84.927886]        [<c0090cdc>] __lock_acquire+0x49c/0x980
> [   84.951660]        [<c0091838>] lock_acquire+0x98/0x100
> [   84.951660]        [<c016a8e8>] sysfs_deactivate+0xb0/0x100
> [   84.962982]        [<c016b1b4>] sysfs_addrm_finish+0x2c/0x6c
> [   84.962982]        [<c016b8bc>] sysfs_remove_dir+0x84/0x98
> [   84.962982]        [<c02590d8>] kobject_del+0x10/0x78
> [   84.974670]        [<c02c29e8>] device_del+0x140/0x170
> [   84.974670]        [<c02c2a24>] device_unregister+0xc/0x18
> [   84.985382]        [<c0276894>] gpio_unexport+0xbc/0xdc
> [   84.985382]        [<c02768c8>] gpio_free+0x14/0xfc
> [   85.001708]        [<c0276a28>] unexport_store+0x78/0x8c
> [   85.001708]        [<c02c5af8>] class_attr_store+0x18/0x24
> [   85.007293]        [<c0169990>] sysfs_write_file+0x100/0x184
> [   85.018981]        [<c0109d48>] vfs_write+0xb4/0x148
> [   85.018981]        [<c0109fd0>] sys_write+0x40/0x70
> [   85.018981]        [<c0013cc0>] ret_fast_syscall+0x0/0x3c
> [   85.035003]
> [   85.035003] -> #0 (sysfs_lock){+.+.+.}:
> [   85.035003]        [<c008f54c>] check_prev_add+0x680/0x698
> [   85.035003]        [<c008f640>] check_prevs_add+0xdc/0x150
> [   85.052093]        [<c008fc18>] validate_chain.clone.24+0x564/0x694
> [   85.052093]        [<c0090cdc>] __lock_acquire+0x49c/0x980
> [   85.052093]        [<c0091838>] lock_acquire+0x98/0x100
> [   85.069885]        [<c047e280>] mutex_lock_nested+0x3c/0x2f4
> [   85.069885]        [<c0275358>] gpio_value_store+0x24/0xcc
> [   85.069885]        [<c02c18dc>] dev_attr_store+0x18/0x24
> [   85.087158]        [<c0169990>] sysfs_write_file+0x100/0x184
> [   85.087158]        [<c0109d48>] vfs_write+0xb4/0x148
> [   85.098297]        [<c0109fd0>] sys_write+0x40/0x70
> [   85.098297]        [<c0013cc0>] ret_fast_syscall+0x0/0x3c
> [   85.109069]
> [   85.109069] other info that might help us debug this:
> [   85.109069]
> [   85.117462]  Possible unsafe locking scenario:
> [   85.117462]
> [   85.117462]        CPU0                    CPU1
> [   85.128417]        ----                    ----
> [   85.128417]   lock(s_active#22);
> [   85.128417]                                lock(sysfs_lock);
> [   85.128417]                                lock(s_active#22);
> [   85.142486]   lock(sysfs_lock);
> [   85.151794]
> [   85.151794]  *** DEADLOCK ***
> [   85.151794]
> [   85.151794] 2 locks held by bash/949:
> [   85.158020]  #0:  (&buffer->mutex){+.+.+.}, at: [<c01698b8>] sysfs_write_file+0x28/0x184
> [   85.170349]  #1:  (s_active#22){++++.+}, at: [<c016996c>] sysfs_write_file+0xdc/0x184
> [   85.170349]
> [   85.178588] stack backtrace:
> [   85.178588] [<c001b824>] (unwind_backtrace+0x0/0xf0) from [<c008de64>] (print_circular_bug+0x100/0x114)
> [   85.193023] [<c008de64>] (print_circular_bug+0x100/0x114) from [<c008f54c>] (check_prev_add+0x680/0x698)
> [   85.193023] [<c008f54c>] (check_prev_add+0x680/0x698) from [<c008f640>] (check_prevs_add+0xdc/0x150)
> [   85.212524] [<c008f640>] (check_prevs_add+0xdc/0x150) from [<c008fc18>] (validate_chain.clone.24+0x564/0x694)
> [   85.212524] [<c008fc18>] (validate_chain.clone.24+0x564/0x694) from [<c0090cdc>] (__lock_acquire+0x49c/0x980)
> [   85.233306] [<c0090cdc>] (__lock_acquire+0x49c/0x980) from [<c0091838>] (lock_acquire+0x98/0x100)
> [   85.233306] [<c0091838>] (lock_acquire+0x98/0x100) from [<c047e280>] (mutex_lock_nested+0x3c/0x2f4)
> [   85.242614] [<c047e280>] (mutex_lock_nested+0x3c/0x2f4) from [<c0275358>] (gpio_value_store+0x24/0xcc)
> [   85.261840] [<c0275358>] (gpio_value_store+0x24/0xcc) from [<c02c18dc>] (dev_attr_store+0x18/0x24)
> [   85.261840] [<c02c18dc>] (dev_attr_store+0x18/0x24) from [<c0169990>] (sysfs_write_file+0x100/0x184)
> [   85.271240] [<c0169990>] (sysfs_write_file+0x100/0x184) from [<c0109d48>] (vfs_write+0xb4/0x148)
> [   85.290008] [<c0109d48>] (vfs_write+0xb4/0x148) from [<c0109fd0>] (sys_write+0x40/0x70)
> [   85.298400] [<c0109fd0>] (sys_write+0x40/0x70) from [<c0013cc0>] (ret_fast_syscall+0x0/0x3c)
> -bash: echo: write error: Operation not permitted
>
> the way to trigger is:
>
> root@legolas:~# cd /sys/class/gpio/
> root@legolas:/sys/class/gpio# echo 2 > export
> root@legolas:/sys/class/gpio# echo 2 > unexport
> root@legolas:/sys/class/gpio# echo 2 > export
> root@legolas:/sys/class/gpio# cd gpio2/
> root@legolas:/sys/class/gpio/gpio2# echo 1 > value

Looks 'sysfs_lock' needn't to be held for unregister, so the patch below may
fix the problem.

Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2012-02-15 13:06:07 -07:00
Grant Likely
1a2d397a6e gpio/powerpc: Eliminate duplication of of_get_named_gpio_flags()
A large chunk of qe_pin_request() is unnecessarily cut-and-paste
directly from of_get_named_gpio_flags().  This patch cuts out the
duplicate code and replaces it with a call to of_get_gpio().

v2: fixed compile error due to missing gpio_to_chip()

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Kumar Gala <galak@kernel.crashing.org>
2011-12-12 13:40:16 -07:00
Grant Likely
64842aad5e gpiolib: output basic details and consolidate gpio device drivers
This patch adds a kernel message, containing GPIO range and device
name on successful device registration, and removes duplicate messages from the following drivers:
	* gpio-adp5588
	* gpio-bt8xx
	* gpio-cs5535
	* gpio-janz-ttl
	* gpio-nomadik
	* gpio-pcf857x
	* gpio-xilinx
	* drivers/of/gpio.c

Signed-off-by: Hartmut Knaack <knaack.h@gmx.de>
[grant.likely@secretlab.ca: squashed 2 patches together]
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2011-12-12 13:40:16 -07:00
Lars-Peter Clausen
7c295975a8 gpio: make gpio_{request,free}_array gpio array parameter const
gpio_{request,free}_array should not (and do not) modify the passed gpio
array, so make the parameter const.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Acked-by: Eric Miao <eric.y.miao@gmail.com>
Acked-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2011-05-27 17:56:45 -06:00
Uwe Kleine-König
3f397c2144 gpio: add trace events for setting direction and value
This patch allows to trace gpio operations using ftrace

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2011-05-20 00:40:19 -06:00
Jean Delvare
8fa0c9bf82 gpiolib: export gpiochip_find
Export function gpiochip_find so that modules can use it.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2011-05-20 00:40:18 -06:00
Thomas Gleixner
b15f052cb8 arm/gpio: Remove three copies of broken and racy debug code
gpiolib plus two gpio implementations in arm fiddle in the guts of
irq_desc in a racy and buggy way. Remove the stuff. I already told the
gpio folks that we can provide that information in a proper way if
necessary.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
LKML-Reference: <20110324212508.931638262@linutronix.de>
2011-03-25 00:02:51 +01:00
Aaro Koskinen
e254811c20 gpiolib: gpio_request_one(): add missing gpio_free()
If GPIO request succeeds, but configuration fails, it should be released.

Signed-off-by: Aaro Koskinen <aaro.koskinen@nokia.com>
Acked-by: Eric Miao <eric.miao@canonical.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-12-22 19:43:33 -08:00
Daniel Gl?ckner
364fadb32b gpiolib: allow nested threaded irqs for poll(2)
The pca953x driver requires the use of threaded irqs as its irq
demultiplexer can sleep.  Our irq handler can be called from any context,
so use request_any_context_irq to allow threaded irqs as well.

Signed-off-by: Daniel Gl?ckner <dg@emlix.com>
Reported-by: Ian Jeffray <ian@jeffray.co.uk>
Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-08-11 08:59:09 -07:00
Daniel Gl?ckner
5ba1821d1b gpiolib: get rid of struct poll_desc and worklet
As sysfs_notify_dirent has been made irq safe, there is no reason to not
call it directly from irq.  With the work_struct removed, the remaining
element in poll_desc is a sysfs_dirent pointer which may not be NULL.  We
can therefore store it directly in the idr and pass it as context to the
irq handler.

Most part of the patch deals with renaming defines and variables to
reflect their new use without functional change.

I also took the opportunity to initialize the idr statically.

Signed-off-by: Daniel Gl?ckner <dg@emlix.com>
Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-08-11 08:59:08 -07:00
David Brownell
9c4ba94661 gpiolib: decouple might_sleep_if() from DEBUG
Be more consistent about runtime programming interface abuse warnings,
which can reduce some confusion and trigger bugfixes.  Based on an
observation and patch from Jani Nikula.

Also update doc to highlight some sleeping-call issues and to match some
recent changes.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Cc: Jani Nikula <ext-jani.1.nikula@nokia.com>
Cc: "Ryan Mallon" <ryan@bluewatersys.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-08-11 08:59:08 -07:00
Linus Torvalds
03c0c29aff Merge branch 'next-devicetree' of git://git.secretlab.ca/git/linux-2.6
* 'next-devicetree' of git://git.secretlab.ca/git/linux-2.6: (63 commits)
  of/platform: Register of_platform_drivers with an "of:" prefix
  of/address: Clean up function declarations
  of/spi: call of_register_spi_devices() from spi core code
  of: Provide default of_node_to_nid() implementation.
  of/device: Make of_device_make_bus_id() usable by other code.
  of/irq: Fix endian issues in parsing interrupt specifiers
  of: Fix phandle endian issues
  of/flattree: fix of_flat_dt_is_compatible() to match the full compatible string
  of: remove of_default_bus_ids
  of: make of_find_device_by_node generic
  microblaze: remove references to of_device and to_of_device
  sparc: remove references to of_device and to_of_device
  powerpc: remove references to of_device and to_of_device
  of/device: Replace of_device with platform_device in includes and core code
  of/device: Protect against binding of_platform_drivers to non-OF devices
  of: remove asm/of_device.h
  of: remove asm/of_platform.h
  of/platform: remove all of_bus_type and of_platform_bus_type references
  of: Merge of_platform_bus_type with platform_bus_type
  drivercore/of: Add OF style matching to platform bus
  ...

Fix up trivial conflicts in arch/microblaze/kernel/Makefile due to just
some obj-y removals by the devicetree branch, while the microblaze
updates added a new file.
2010-08-05 15:57:35 -07:00
Jon Povey
6a99ad4a2e gpio: fix spurious printk when freeing a gpio
When freeing a gpio that has not been exported, gpio_unexport() prints a
debug message when it should just fall through silently.

Example spurious message:

	gpio_unexport: gpio0 status -22

Signed-off-by: Jon Povey <jon.povey@racelogic.co.uk>
Cc: David Brownell <david-b@pacbell.net>
Acked-by: Uwe Kleine-K?nig <u.kleine-koenig@pengutronix.de>
Cc: Gregory Bean <gbean@codeaurora.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-07-27 14:32:07 -07:00