This is the convention used in most parts of the kernel including DT
counterpart of I2C slave enumeration. To make things consistent do the same
for ACPI I2C slave enumeration path as well.
Signed-off-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: NWolfram Sang <wsa@the-dreams.de>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

The dln2 driver was initialising a gpiolib private field, which is now
gone.
Reported-by: Nkbuild test robot <fengguang.wu@intel.com>
Signed-off-by: NJohan Hovold <johan@kernel.org>
Acked-by: NAlexandre Courbot <acourbot@nvidia.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Signed-off-by: NAxel Lin <axel.lin@ingics.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Add binding for Broadcom STB "UPG GIO" GPIO controller.
Signed-off-by: NGregory Fong <gregory.0xf0@gmail.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Move irq trigger flags, which as sysfs-interface specific, to the class
device data.

This avoids accessing the gpio-descriptor flags field using non-atomic
operations without any locking, and allows for a more clear separation
of the sysfs interface from gpiolib core.
Signed-off-by: NJohan Hovold <johan@kernel.org>
Reviewed-by: NAlexandre Courbot <acourbot@nvidia.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Remove FLAG_SYSFS_DIR, which is sysfs-interface specific, and store it
in the class-device data instead.

Note that the flag is only used during export.
Signed-off-by: NJohan Hovold <johan@kernel.org>
Reviewed-by: NAlexandre Courbot <acourbot@nvidia.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Rename active-low helper using common prefix.

Also remove unnecessary manipulation of value argument.
Signed-off-by: NJohan Hovold <johan@kernel.org>
Reviewed-by: NAlexandre Courbot <acourbot@nvidia.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Make sure to deregister the class device (and release the irq) while
holding the sysfs lock in gpio_unexport to prevent racing with
gpio_export.

Note that this requires the recently introduced per-gpio locking to
avoid a deadlock with the kernfs active protection when waiting for the
attribute operations to drain during deregistration.
Signed-off-by: NJohan Hovold <johan@kernel.org>
Reviewed-by: NAlexandre Courbot <acourbot@nvidia.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Add a per-gpio mutex to serialise attribute operations rather than use
one global mutex for all gpios and chips.

Having a single global lock for all gpios in a system adds unnecessary
latency to the sysfs interface, and especially when having gpio
controllers connected over slow buses.

Now that the global gpio-sysfs interrupt table is gone and with per-gpio
data in place, we can easily switch to using a more fine-grained locking
scheme.

Keep the global mutex to serialise the global (class) operations of gpio
export and unexport and chip removal.

Also document the locking assumptions made.

Note that this is also needed to fix a race between gpiod_export and
gpiod_unexport.
Signed-off-by: NJohan Hovold <johan@kernel.org>
Reviewed-by: NAlexandre Courbot <acourbot@nvidia.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Drop unnecessary locking from gpiod_export_link. If the class device has
not already been unregistered, class_find_device returns the ref-counted
class device so there's no need for locking.
Signed-off-by: NJohan Hovold <johan@kernel.org>
Reviewed-by: NAlexandre Courbot <acourbot@nvidia.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Remove goto from success path.
Signed-off-by: NJohan Hovold <johan@kernel.org>
Reviewed-by: NAlexandre Courbot <acourbot@nvidia.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Add separate helper functions for irq request and free.
Signed-off-by: NJohan Hovold <johan@kernel.org>
Reviewed-by: NAlexandre Courbot <acourbot@nvidia.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Only call irq helper if actually reconfiguring interrupt state.

This is a preparatory step in introducing separate gpio-irq request and
free functions.
Signed-off-by: NJohan Hovold <johan@kernel.org>
Reviewed-by: NAlexandre Courbot <acourbot@nvidia.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Store the value sysfs entry in the gpiod data rather than in a global
table accessed through an index stored in the overloaded gpio-descriptor
flag field.
Signed-off-by: NJohan Hovold <johan@kernel.org>
Reviewed-by: NAlexandre Courbot <acourbot@nvidia.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Remove redundant gpio-descriptor parameters from sysfs_set_active_low and
gpio_setup_irq.
Signed-off-by: NJohan Hovold <johan@kernel.org>
Reviewed-by: NAlexandre Courbot <acourbot@nvidia.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Add gpiod class-device data.

This is a first step in getting rid of the insane gpio-descriptor flag
overloading, backward irq-interface implementation, and course grained
sysfs-interface locking (a single static mutex for every operation on
all exported gpios in a system).
Signed-off-by: NJohan Hovold <johan@kernel.org>
Reviewed-by: NAlexandre Courbot <acourbot@nvidia.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

The attribute operations will never be called for an unregistered device
so remove redundant checks for FLAG_EXPORT.

Note that kernfs will also guarantee that any active sysfs operation has
finished before the attribute is removed during deregistration.
Signed-off-by: NJohan Hovold <johan@kernel.org>
Reviewed-by: NAlexandre Courbot <acourbot@nvidia.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Make sure to release any irq only after the class device has been
deregistered.

This avoids a race between gpiod_unexport and edge_store, where an irq
could be allocated just before the gpio class device is deregistered
without relying on FLAG_EXPORT and the global sysfs lock.

Note that there is no need to hold the sysfs lock when releasing the irq
after the class device is gone as kernfs will prevent further attribute
operations.
Signed-off-by: NJohan Hovold <johan@kernel.org>
Reviewed-by: NAlexandre Courbot <acourbot@nvidia.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Use DEVICE_ATTR_RO and DEVICE_ATTR_RW rather than specifying masks and
callbacks directly.
Signed-off-by: NJohan Hovold <johan@kernel.org>
Reviewed-by: NAlexandre Courbot <acourbot@nvidia.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Remove gpiod_sysfs_set_active_low (and gpio_sysfs_set_active_low) which
allowed code to change the polarity of a gpio line even after it had
been exported through sysfs.

Drivers should not care, and generally does not know, about gpio-line
polarity which is a hardware feature that needs to be described by
firmware.

It is currently possible to define gpio-line polarity in device-tree and
acpi firmware or using platform data. Userspace can also change the
polarity through sysfs.

Note that drivers using the legacy gpio interface could still use
GPIOF_ACTIVE_LOW to change the polarity before exporting the gpio.

There are no in-kernel users of this interface.

Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Harry Wei <harryxiyou@gmail.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: linux-doc@vger.kernel.org
Cc: linux-kernel@zh-kernel.org
Cc: linux-arch@vger.kernel.org
Signed-off-by: NJohan Hovold <johan@kernel.org>
Reviewed-by: NAlexandre Courbot <acourbot@nvidia.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Rename the gpio-chip export/unexport functions to the more descriptive
names gpiochip_sysfs_register and gpiochip_sysfs_unregister.
Signed-off-by: NJohan Hovold <johan@kernel.org>
Reviewed-by: NAlexandre Courbot <acourbot@nvidia.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Clean gpio-chip class device registration and deregistration.

The class device is registered when a gpio-chip is added (or from
gpiolib_sysfs_init post-core init call), and deregistered when the chip
is removed.

Store the class device in struct gpio_chip directly rather than do a
class-device lookup on deregistration. This also removes the need for
the exported flag.
Signed-off-by: NJohan Hovold <johan@kernel.org>
Reviewed-by: NAlexandre Courbot <acourbot@nvidia.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Reduce scope of sysfs_lock protection during chip export and unexport,
which is only needed to prevent gpiod (re-)exports during chip removal.
Signed-off-by: NJohan Hovold <johan@kernel.org>
Reviewed-by: NAlexandre Courbot <acourbot@nvidia.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Put the recently introduced gpio-chip pointer to some more use in
gpiod_export.
Signed-off-by: NJohan Hovold <johan@kernel.org>
Reviewed-by: NAlexandre Courbot <acourbot@nvidia.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Drivers should call gpiochip_lock_as_irq (which prevents the pin
direction from being changed) in their irq_request_resources callbacks
but some drivers currently fail to do so.

Instead a second, explicit and often redundant call to lock-as-irq is
made by the sysfs-interface implementation after an irq has been
requested.

Move the explicit call before the irq-request to match the unlock done
after the irq is later released. Note that this also fixes an irq leak,
should the explicit call ever have failed.

Also add a comment about removing the redundant call once the broken
drivers have been fixed.
Signed-off-by: NJohan Hovold <johan@kernel.org>
Reviewed-by: NAlexandre Courbot <acourbot@nvidia.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Clean up gpiochip_remove somewhat and only output warning about removing
chip with GPIOs requested once.
Signed-off-by: NJohan Hovold <johan@kernel.org>
Reviewed-by: NAlexandre Courbot <acourbot@nvidia.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Linux 4.1-rc3

Fix kernel-doc format:
- Add gpio-width description
- Remove additional "inited" variable description
- Add return value description - xgpio_remove
Signed-off-by: NMichal Simek <michal.simek@xilinx.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

priv->irq is allocated using devm_kzalloc so there is no need to memset it.
Signed-off-by: NChristophe Jaillet <christophe.jaillet@wanadoo.fr>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

The platform_device_id is not modified by the driver and core uses it as
const.
Signed-off-by: NKrzysztof Kozlowski <k.kozlowski.k@gmail.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

This file is built off of a tristate Kconfig option and also contains
modular function calls so it should explicitly include module.h to
avoid compile breakage during header shuffles done in the future.

Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Alexandre Courbot <gnurou@gmail.com>
Cc: linux-gpio@vger.kernel.org
Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

ACPI specification knows two types of GPIOs: GpioIo and GpioInt. The latter
is used to describe that a given device interrupt line is connected to a
specific GPIO pin. Typical ACPI _CRS entry for such device looks like
below:

    Name (_CRS, ResourceTemplate ()
    {
        I2cSerialBus (0x004A, ControllerInitiated, 0x00061A80,
                      AddressingMode7Bit, "\\_SB.PCI0.I2C6",
                      0x00, ResourceConsumer)
        GpioIo (Exclusive, PullDefault, 0x0000, 0x0000,
                IoRestrictionOutputOnly, "\\_SB.GPO0",
                0x00, ResourceConsumer)
        {
            0x004B
        }
        GpioInt (Level, ActiveLow, Shared, PullDefault, 0x0000,
                 "\\_SB.GPO0", 0x00, ResourceConsumer)
        {
            0x004C
        }
    })

Currently drivers need to request a GPIO corresponding to the right GpioInt
and then translate that to Linux IRQ number. This adds unnecessary lines of
boiler-plate code.

We can ease this a bit by introducing acpi_dev_gpio_irq_get() analogous to
of_irq_get(). This function translates given GpioInt resource under the
device in question to the suitable Linux IRQ number.
Signed-off-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

All supported iMX GPIO controllers store configured GPIO output value
in GPIO_DR data register, which is represented by GPIO generic reg_set.
Provide a BGPIOF_READ_OUTPUT_REG_SET flag to bgpio_init() to allow
correct getting of previously set output value.
Signed-off-by: NVladimir Zapolskiy <vladimir_zapolskiy@mentor.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Adding a BGPIOF_READ_OUTPUT_REG_SET initialization flag to GPIO
generic MMIO driver makes possible to remove a private get() value
function from the driver.
Signed-off-by: NVladimir Zapolskiy <vladimir_zapolskiy@mentor.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

The change introduces BGPIOF_READ_OUTPUT_REG_SET flag for gpio-generic
GPIO chip implementation, which allows to get correct configured value
from reg_set register, input value is still get from reg_dat.
Signed-off-by: NVladimir Zapolskiy <vladimir_zapolskiy@mentor.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Pull drm fixes from Dave Airlie:
 "I really need to get back to sending these on my Friday, instead of my
  Monday morning, but nothing too amazing in here: a few amdkfd fixes, a
  few radeon fixes, i915 fixes, one tegra fix and one core fix"

* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux:
  drm: Zero out invalid vblank timestamp in drm_update_vblank_count.
  drm/tegra: Don't use vblank_disable_immediate on incapable driver.
  drm/radeon: stop trying to suspend UVD sessions
  drm/radeon: more strictly validate the UVD codec
  drm/radeon: make UVD handle checking more strict
  drm/radeon: make VCE handle check more strict
  drm/radeon: fix userptr lockup
  drm/radeon: fix userptr BO unpin bug v3
  drm/amdkfd: Initialize sdma vm when creating sdma queue
  drm/amdkfd: Don't report local memory size
  drm/amdkfd: allow unregister process with queues
  drm/i915: Drop PIPE-A quirk for 945GSE HP Mini
  drm/i915: Sink rate read should be saved in deca-kHz
  drm/i915/dp: there is no audio on port A
  drm/i915: Add missing MacBook Pro models with dual channel LVDS
  drm/i915: Assume dual channel LVDS if pixel clock necessitates it
  drm/radeon: don't setup audio on asics that don't support it
  drm/radeon: disable semaphores for UVD V1 (v2)

misc i915 fixes.

* tag 'drm-intel-fixes-2015-05-08' of git://anongit.freedesktop.org/drm-intel:
  drm/i915: Drop PIPE-A quirk for 945GSE HP Mini
  drm/i915: Sink rate read should be saved in deca-kHz
  drm/i915/dp: there is no audio on port A
  drm/i915: Add missing MacBook Pro models with dual channel LVDS
  drm/i915: Assume dual channel LVDS if pixel clock necessitates it

Since commit 844b03f2 we make
sure that after vblank irq off, we return the last valid
(vblank count, vblank timestamp) pair to clients, e.g., during
modesets, which is good.

An overlooked side effect of that commit for kms drivers without
support for precise vblank timestamping is that at vblank irq
enable, when we update the vblank counter from the hw counter, we
can't update the corresponding vblank timestamp, so now we have a
totally mismatched timestamp for the new count to confuse clients.

Restore old client visible behaviour from before Linux 3.17, but
zero out the timestamp at vblank counter update (instead of disable
as in original implementation) if we can't generate a meaningful
timestamp immediately for the new vblank counter. This will fix
this regression, so callers know they need to retry again later
if they need a valid timestamp, but at the same time preserves
the improvements made in the commit mentioned above.
Signed-off-by: NMario Kleiner <mario.kleiner.de@gmail.com>
Cc: <stable@vger.kernel.org> #v3.17+

Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Signed-off-by: NDave Airlie <airlied@redhat.com>

Pull ARM fixes from Russell King:
 "A set of ARM fixes:

   - fix an off-by-one error in the iommu DMA ops, which caused errors
     with a 4GiB size.

   - remove comments mentioning the non-existent CONFIG_CPU_ARM1020_CPU_IDLE
     macro.

   - remove useless CONFIG_CPU_ICACHE_STREAMING_DISABLE blocks, where
     this symbol never appeared in any Kconfig.

   - fix Feroceon code to cope with a previous change correctly (it
     incorrectly left an additional word in an assembly structure
     definition)

   - avoid a misleading IRQ affinity warning in the ARM PMU code for
     IRQs which are already affine to their CPUs.

   - fix the node name printed in the IRQ affinity warning"

* 'fixes' of git://ftp.arm.linux.org.uk/~rmk/linux-arm:
  ARM: 8352/1: perf: Fix the pmu node name in warning message
  ARM: 8351/1: perf: don't warn about missing interrupt-affinity property for PPIs
  ARM: 8350/1: proc-feroceon: Fix feroceon_proc_info macro
  ARM: 8349/1: arch/arm/mm/proc-arm925.S: remove dead #ifdef block
  ARM: 8348/1: remove comments on CPU_ARM1020_CPU_IDLE
  ARM: 8347/1: dma-mapping: fix off-by-one check in arm_setup_iommu_dma_ops