The Dell XPS13 9365 has an INT33D2 ACPI node with no GPIOs, causing
the following error in dmesg:

[    7.172275] soc_button_array: probe of INT33D2:00 failed with error -2

This commit silences this, by returning -ENODEV when there are no GPIOs.

BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=196679
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

Prepare second round of input updates for 4.13 merge window.

Extend xen_kbdfront to provide multi-touch support to unprivileged domains.

Signed-off-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
[dtor: factor out various sub-protocols - multitouch, single touch, keys]
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

Prepare input updates for 4.13 merge window.

We are passing a buffer with ACPI_ALLOCATE_BUFFER set to
acpi_evaluate_object, so we must free it when we are done with it.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

Xen input para-virtual protocol defines string constants
used by both back and frontend. Use those instead of
explicit strings in the frontend driver.

Signed-off-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

At least on devices with the AXP288 PMIC the device is expected to
wakeup from suspend when the power-button gets pressed, add support
for this.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

acpi_dev_found checks that there is a matching ACPI node, but it
may be disabled (_STA method returns 0) in which case the
soc_button_array driver will not bind to it and axp20x-pek should
handle the power-button.

This commit switches from acpi_dev_found to acpi_dev_present to
avoid not registering an input-dev for the powerbutton when there
is a disabled PNP0C40 device.

The ACPI-6.0 standard defines a standard gpio button device using
the ACPI0011 HID replacing the custom PNP0C40 gpio device, many
newer devices define both PNP0C40 and ACPI0011 devices enabling one
or the other depending on whether the BIOS thinks it is going to boot
Android or Windows.

This commit adds a check for the ACPI0011 device, so that if
either device is present *and* enabled we don't register an input-dev
for the powerbutton.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

Commit 9b13a4ca8d2c ("Input: axp20x-pek - do not register input device
on some systems") added a check for the INTCFD9 ACPI device which also
handles the powerbutton as on some systems the powerbutton is connected
to both the PMIC, handled by axp20x-pek, and to a gpio on the SoC, handled
by soc_button_array which attaches itself to the INTCFD9 ACPI device.

Testing + comparing DSDTs has shown that this only happens on Cherry
Trail devices with an AXP288 PMIC, the AXP288 PMIC is also used on
Bay Trail devices but there the power button is only connected to
the PMIC and not handled by soc_button_array.

This means that the INTCFD9 check has caused a regression on Bay Trail
devices, causing power-button presses to no longer be seen.

This commit fixes this by limiting the check to devices where the ACPI
node for the AXP288 contains a _HRV (hardware revision) attribute with
a value of 3 which indicates we are dealing with a Cherry Trail platform.

Fixes: 9b13a4ca8d2c ("Input: axp20x-pek - do not register input ...")
Reported-by: Сергей Трусов <t.rus76@ya.ru>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

Pull GPIO updates from Linus Walleij:
 "This is the bulk of GPIO changes for the v4.12 kernel cycle.

  Core changes:

   - Return NULL from gpiod_get_optional() when GPIOLIB is disabled.
     This was a much discussed change. It affects use cases where people
     write drivers that might or might not be using GPIO resources. I
     have decided that this is the lesser evil right now.

   - Make gpiod_count() behave consistently across different hardware
     descriptions.

   - Fix the syntax around open drain/open source to not infer active
     high/low semantics.

  New drivers:

   - A new single-register fixed-direction framework driver for hardware
     that have lines controlled by a single register that just work in
     one direction (out or in), including IRQ support.

   - Support the Fintek F71889A GPIO SuperIO controller.

   - Support the National NI 169445 MMIO GPIO.

   - Support for the X-Gene derivative of the DWC GPIO controller

   - Support for the Rohm BD9571MWV-M PMIC GPIO controller.

   - Refactor the Gemini GPIO driver to a generic Faraday FTGPIO driver
     and replace both the Gemini and the Moxa ART custom drivers with
     this driver.

  Driver improvements:

   - A whole slew of drivers have their spinlocks chaned to raw
     spinlocks as they provide irqchips, and thus we are progressing on
     realtime compliance.

   - Use devm_irq_alloc_descs() in a slew of drivers, getting managed
     resources.

   - Support for the embedded PWM controller inside the MVEBU driver.

   - Debounce, open source and open drain support for the Aspeed driver.

   - Misc smaller fixes like spelling and syntax and whatnot"

* tag 'gpio-v4.12-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (77 commits)
  gpio: f7188x: Add a missing break
  gpio: omap: return error if requested debounce time is not possible
  gpio: Add ROHM BD9571MWV-M PMIC GPIO driver
  gpio: gpio-wcove: fix GPIO IRQ status mask
  gpio: DT bindings, move tca9554 from pcf857x to pca953x
  gpio: move tca9554 from pcf857x to pca953x
  gpio: arizona: Correct check whether the pin is an input
  gpio: Add XRA1403 DTS binding documentation
  dt-bindings: add exar to vendor prefixes list
  gpio: gpio-wcove: fix irq pending status bit width
  gpio: dwapb: use dwapb_read instead of readl_relaxed
  gpio: aspeed: Add open-source and open-drain support
  gpio: aspeed: Add debounce support
  gpio: aspeed: dt: Add optional clocks property
  gpio: aspeed: dt: Fix description alignment in bindings document
  gpio: mvebu: Add limited PWM support
  gpio: Use unsigned int for interrupt numbers
  gpio: f7188x: Add F71889A GPIO support.
  gpio: core: Decouple open drain/source flag with active low/high
  gpio: arizona: Correct handling for reading input GPIOs
  ...