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

  Core changes:

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

   - Return error on seek operations for the chardev.

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

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

  New drivers:

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

  New features:

   - Various cleanups to various drivers"

* tag 'gpio-v4.10-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (49 commits)
  gpio: merrifield: Implement gpio_get_direction callback
  gpio: merrifield: Add support for hardware debouncer
  gpio: chardev: Return error for seek operations
  gpio: arizona: Tidy up probe error path
  gpio: arizona: Remove pointless set of platform drvdata
  gpio: pl061: delete platform data handling
  gpio: pl061: move platform data into driver
  gpio: pl061: rename variable from chip to pl061
  gpio: pl061: rename state container struct
  gpio: pl061: use local state for parent IRQ storage
  gpio: set explicit nesting on drivers
  gpio: simplify adding threaded interrupts
  gpio: vf610: use builtin_platform_driver
  gpio: axp209: use correct register for GPIO input status
  gpio: stmpe: fix interrupt handling bug
  gpio: em: depnd on ARCH_SHMOBILE
  gpio: zx: depend on ARCH_ZX
  gpio: x86: update config dependencies for x86 specific hardware
  gpio: mb86s7x: use builtin_platform_driver
  gpio: etraxfs: use builtin_platform_driver
  ...

This tries to simplify the use of CONFIG_GPIOLIB_IRQCHIP when
using threaded interrupts: add a new call
gpiochip_irqchip_add_nested() to indicate that we're dealing
with a nested rather than a chained irqchip, then create a
separate gpiochip_set_nested_irqchip() to mirror
the gpiochip_set_chained_irqchip() call to connect the
parent and child interrupts.

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

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

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

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

Cc: Lars Poeschel <poeschel@lemonage.de>
Cc: Octavian Purdila <octavian.purdila@intel.com>
Cc: Daniel Baluta <daniel.baluta@intel.com>
Cc: Bin Gao <bin.gao@linux.intel.com>
Cc: Mika Westerberg <mika.westerberg@linux.intel.com>
Cc: Ajay Thomas <ajay.thomas.david.rajamanickam@intel.com>
Cc: Semen Protsenko <semen.protsenko@globallogic.com>
Cc: Alexander Stein <alexander.stein@systec-electronic.com>
Cc: Phil Reid <preid@electromag.com.au>
Cc: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Cc: Patrice Chotard <patrice.chotard@st.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

gpiod_set_value() is preffered interface these days, so add a
pointer. Also fix a missing ).

Signed-off-by: Pavel Machek <pavel@ucw.cz>
[Fixed some grammar and reworded]
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

When using GPIO irqchip helpers to setup irqchip for a gpiolib based
driver, it is not possible to select which GPIOs to add to the IRQ domain.
Instead it just adds all GPIOs which is not always desired. For example
there might be GPIOs that for some reason cannot generated normal
interrupts at all.

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

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

Suggested-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

The GPIOLIB is now selectable explicitly, and always available
for all archs. All archs that require GPIOLIB are switched to
select GPIOLIB directly. Delete the hairy ARCH_REQUIRE_GPIOLIB
and ARCH_WANTS_OPTIONAL_GPIOLIB Kconfig symbols.

Cc: Michael Büsch <m@bues.ch>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

Make the text clearer, remove reference to confusing "positive"
and "negative" and elaborate a bit.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

This has been a totally undocumented feature for years so add some
generic concepts and documentation about open drain/source, include
some facts on how we now support for hardware.

Cc: Michael Hennerich <michael.hennerich@analog.com>
Cc: Nicolas Saenz Julienne <nicolassaenzj@gmail.com>
Cc: H. Nikolaus Schaller <hns@goldelico.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

The 'dev_id' parameter of the GPIO_LOOKUP{,_IDX} macros were removed by
commit ad824783fb23 ("gpio: better lookup method for platform GPIOs").

Update the documentation to reflect that.

Signed-off-by: Gabor Juhos <juhosg@openwrt.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>