The original code of gpiodev_add_to_list is not very clear which
lead to bugs or compiling warning, reference the following patches:
Bugs:
1.  Commit ef7c7553 ("gpiolib: improve overlap check of range of
    gpio").
2.  Commit 96098df1 ("gpiolib: fix chip order in gpio list")

Warning:
1.  Commit e28ecca6 ("gpio: fix warning about iterator").
of gpio").

There is a off-list discussion about how to improve it consequently.
This commit try to follow this by rewriting the whole functions.

Tested pass with my gpio mockup driver and test scripts[1].

[1] http://www.spinics.net/lists/linux-gpio/msg09598.htmlSuggested-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NBamvor Jian Zhang <bamvor.zhangjian@linaro.org>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

There is no build dependency for this driver, so enable COMPILE_TEST to get
better build coverage.
Signed-off-by: NAxel Lin <axel.lin@ingics.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

These fields are initialized by bgpio_init() with exactly the same settings
so remove the redundant code.
Signed-off-by: NAxel Lin <axel.lin@ingics.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

I named the field representing the current user of GPIO line as
"label" but this is too vague and ambiguous. Before anyone gets
confused, rename it to "consumer" and indicate clearly in the
documentation that this is a string set by the user of the line.

Also clean up leftovers in the documentation.
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

We started to assign the gpio_device as parent for the sysfs
but this changes the expected layout of sysfs. Restore the
previous behaviour.
Signed-off-by: NBamvor Jian Zhang <bamvor.zhangjian@linaro.org>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

There is no build dependency for this driver, so enable COMPILE_TEST to get
better build coverage.
Signed-off-by: NAxel Lin <axel.lin@ingics.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

This driver has .can_sleep flag set.
So the pisosr_gpio_get() can be called from contexts that can sleep.
Thus use the cansleep() variant in pisosr_gpio_refresh().
Signed-off-by: NAxel Lin <axel.lin@ingics.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

gpio->load_gpio is optional, so use devm_gpiod_get_optional instead.
Signed-off-by: NAxel Lin <axel.lin@ingics.com>
Acked-by: NAndrew F. Davis <afd@ti.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

ret variable can contain error values and is compared with zero.
Its type must be signed.

The problem has been detected using coccinelle script
scripts/coccinelle/tests/unsigned_lesser_than_zero.cocci
Signed-off-by: NAndrzej Hajda <a.hajda@samsung.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Make use of ARCH_RENESAS in place of ARCH_SHMOBILE.

This is part of an ongoing process to migrate from ARCH_SHMOBILE to
ARCH_RENESAS the motivation for which being that RENESAS seems to be a more
appropriate name than SHMOBILE for the majority of Renesas ARM based SoCs.
Signed-off-by: NSimon Horman <horms+renesas@verge.net.au>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Both chip->base and chip->label are correctly set by bgpio_init().
Signed-off-by: NAxel Lin <axel.lin@ingics.com>
Tested-by: NJulien Grossholtz <julien.grossholtz@savoirfairelinux.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Use list_for_each_entry to simplify the code a bit.
Signed-off-by: NAxel Lin <axel.lin@ingics.com>
Acked-by: NGregory Fong <gregory.0xf0@gmail.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Move the code checking valid gpio count to cover both DT and non-DT cases.
Signed-off-by: NAxel Lin <axel.lin@ingics.com>
Acked-by: NAlban Bedel <albeu@free.fr>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

devm_get_gpiod_from_child() tries several property suffixes to find a
GPIO descriptor. If all suffixes fail and no probe deferral has been
detected, it returns the error of the last try.

However, if any but the last try fails with a real error (e.g. -EBUSY),
this error is not propagated, and -ENOENT will be returned.
This confuses drivers that e.g. want to detect if a GPIO is already in
use.

To fix this, change the loop logic to continue on -ENOENT, which
indicates the property was not found and the next suffix should be
tried, and propagate all other detected errors.
Signed-off-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

This fixes the wrongly indicated lines in the userspace
ABI: test for the right BITS, do not treat bit numbers as
bitmasks.
Reported-by: NMarkus Pargmann <mpa@pengutronix.de>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Commit cb464a88e1ed ("gpio: make the gpiochip a real device") call
gpiochip_sysfs_unregister after the gpiochip is empty. It lead to the
following crash:

[  163.503994] Unable to handle kernel NULL pointer dereference at virtual address 0000007c
[...]
[  163.525394] [<ffffffc0003719a0>] gpiochip_sysfs_unregister+0x44/0xa4
[  163.525611] [<ffffffc00036f6a0>] gpiochip_remove+0x24/0x154
[  163.525861] [<ffffffbffc00f0a4>] mockup_gpio_remove+0x38/0x64 [gpio_mockup]
[  163.526101] [<ffffffc00042b4b4>] platform_drv_remove+0x24/0x64
[  163.526313] [<ffffffc000429cc8>] __device_release_driver+0x7c/0xfc
[  163.526525] [<ffffffc000429e54>] driver_detach+0xbc/0xc0
[  163.526700] [<ffffffc000429014>] bus_remove_driver+0x58/0xac
[  163.526883] [<ffffffc00042a4cc>] driver_unregister+0x2c/0x4c
[  163.527067] [<ffffffc00042b5c0>] platform_driver_unregister+0x10/0x18
[  163.527284] [<ffffffbffc00f340>] mock_device_exit+0x10/0x38 [gpio_mockup]
[  163.527593] [<ffffffc00011cefc>] SyS_delete_module+0x1b8/0x1fc
[  163.527799] [<ffffffc000085d8c>] __sys_trace_return+0x0/0x4
[  163.528049] Code: 940d74b4 f9019abf aa1303e0 940d7439 (7940fac0)
[  163.536273] ---[ end trace 3d1329be504af609 ]---

This patch fix this by changing the code back.
Signed-off-by: NBamvor Jian Zhang <bamvor.zhangjian@linaro.org>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

If spi_read() fails then we just returned but we missed unlocking the
mutex.
Signed-off-by: NSudip Mukherjee <sudip@vectorindia.org>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Enable X-Gene standby GPIO controller as interrupt controller to provide
its own resources. This avoids ambiguity where GIC interrupt resource is
use as X-Gene standby GPIO interrupt resource in user driver.
Signed-off-by: NY Vo <yvo@apm.com>
Signed-off-by: NQuan Nguyen <qnguyen@apm.com>
Acked-by: NMarc Zyngier <marc.zyngier@arm.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

This adds a GPIO line ABI for getting name, label and a few select
flags from the kernel.

This hides the kernel internals and only tells userspace what it
may need to know: the different in-kernel consumers are masked
behind the flag "kernel" and that is all userspace needs to know.

However electric characteristics like active low, open drain etc
are reflected to userspace, as this is important information.

We provide information on all lines on all chips, later on we will
likely add a flag for the chardev consumer so we can filter and
display only the lines userspace actually uses in e.g. lsgpio,
but then we first need an ABI for userspace to grab and use
(get/set/select direction) a GPIO line.

Sample output from "lsgpio" on ux500:

GPIO chip: gpiochip7, "8011e000.gpio", 32 GPIO lines
        line 0: unnamed unlabeled
        line 1: unnamed unlabeled
(...)
        line 25: unnamed "SFH7741 Proximity Sensor" [kernel output open-drain]
        line 26: unnamed unlabeled
(...)
Tested-by: NMichael Welling <mwelling@ieee.org>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

The gpio_chip label is useful for userspace to understand what
kind of GPIO chip it is dealing with. Let's store a copy of this
label in the gpio_device, add it to the struct passed to userspace
for GPIO_GET_CHIPINFO_IOCTL and modify lsgpio to show it.
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Just as it says: after adding the proper interfaces to gpiolib,
this is no longer needed.
Suggested-by: NNicolas Saenz Julienne <nicolassaenzj@gmail.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

The ks8695 gpio driver has its own copy of the irq_to_gpio()
function. This is completely unused in the mainline kernel
after we converted all remaining users several years ago,
so we can remove the definition as well.
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

The use of kmalloc() to allocate the gpio_device leaves the contained struct
device object in an unknown state.  Calling dev_set_name() on a struct device
of unknown state can trigger the free() of an invalid pointer, as seen in the
following backtrace (collected by Tony Lindgren):

  kfree
  kobject_set_name_vargs
  dev_set_name
  gpiochip_add_data
  omap_gpio_probe
  platform_drv_probe
  ...
Reported-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Reported-by: NMichael Welling <mwelling@ieee.org>
Reported-by: NTony Lindgren <tony@atomide.com>
Tested-by: NMichael Welling <mwelling@ieee.org>
Tested-by: NTony Lindgren <tony@atomide.com>
Signed-off-by: NJosh Cartwright <joshc@ni.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Since devm_kzalloc can be failed in memory pressure,
it needs to check and return -ENOMEM
Signed-off-by: NInsu Yun <wuninsu@gmail.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

The .direction_output callback should set proper output level.
Signed-off-by: NAxel Lin <axel.lin@ingics.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

The .direction_output callback should set proper output level.
Signed-off-by: NAxel Lin <axel.lin@ingics.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

My left hand merges code to privatize the descriptor handling
while my right hand merges drivers that poke around and
disrespect with the same gpiolib internals.

So let's expose the proper APIs for drivers to ask the gpiolib
core if a line is marked as open drain or open source and
get some order around things so this driver compiles again.
Reported-by: NStephen Rothwell <sfr@canb.auug.org.au>
Cc: Nicolas Saenz Julienne <nicolassaenzj@gmail.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

This fixes a possible NULL pointer deference in the function,
davinci_gpio_probe due to the function, gpio2regs being able
to return a NULL pointer if it rans to get the registers for
the gpio devices on a davinci board. Furthermore if this does
arise return -ENXIO to signal callers that this case has arisen
and avoiding setting the regs or other pointer values on the
Signed-off-by: NNicholas Krause <xerofoify@gmail.com>
Reviewed-by: NAlexandre Courbot <acourbot@nvidia.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Most arches have an asm/gpio.h that merely includes linux/gpio.h.  The
others select ARCH_HAVE_CUSTOM_GPIO_H, and when that's selected,
linux/gpio.h includes asm/gpio.h.

Therefore, code should include linux/gpio.h instead of including asm/gpio.h
directly.

Remove includes of asm/gpio.h, adding an include of linux/gpio.h when
necessary.

This is a follow-on to 7563bbf8 ("gpiolib/arches: Centralise
bolierplate asm/gpio.h").
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Acked-by: NThomas Gleixner <tglx@linutronix.de>
Acked-by: NArnd Bergmann <arnd@arndb.de>
Acked-by: NAlexandre Courbot <acourbot@nvidia.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

No flags are required for bgpio_init in the TS-4800 gpio driver. This
patch set zero instead. The driver will have the same behaviour since
the & operator between the flags already resulted to zero.

Fixes: 5041e791 ("gpio: add TS-4800 fpga GPIO support")
Signed-off-by: NJulien Grossholtz <julien.grossholtz@savoirfairelinux.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

We move to manage this pointer under gpiolib control rather than
leave it in the subdevice's gpio_chip. We can not NULL it after
gpiochip_remove so at to keep things tight.
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Instead of keeping this reference to the pin ranges in the
client driver-supplied gpio_chip, move it to the internal
gpio_device as the drivers have no need to inspect this.
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

By the time request_region is called in the WinSystems WS16C48 GPIO
driver, a corresponding device structure has already been allocated. The
devm_request_region function should be used to help simplify the cleanup
code and reduce the possible points of failure.
Signed-off-by: NWilliam Breathitt Gray <vilhelm.gray@gmail.com>
Reviewed-by: NAlexandre Courbot <acourbot@nvidia.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

By the time request_region is called in the SMSC SCH311x GPIO driver, a
corresponding device structure has already been allocated. The
devm_request_region function should be used to help simplify the cleanup
code and reduce the possible points of failure.
Signed-off-by: NWilliam Breathitt Gray <vilhelm.gray@gmail.com>
Reviewed-by: NAlexandre Courbot <acourbot@nvidia.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

By the time request_region is called in the Intel ICH series GPIO
driver, a corresponding device structure has already been allocated. The
devm_request_region function should be used to help simplify the cleanup
code and reduce the possible points of failure.

Cc: Peter Tyser <ptyser@xes-inc.com>
Signed-off-by: NWilliam Breathitt Gray <vilhelm.gray@gmail.com>
Reviewed-by: NAlexandre Courbot <acourbot@nvidia.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

By the time request_region is called in the AMD 8111 GPIO driver, a
corresponding device structure has already been allocated. The
devm_request_region function should be used to help simplify the cleanup
code and reduce the possible points of failure.
Signed-off-by: NWilliam Breathitt Gray <vilhelm.gray@gmail.com>
Reviewed-by: NAlexandre Courbot <acourbot@nvidia.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

By the time request_region is called in the ACCES 104-IDIO-16 GPIO
driver, a corresponding device structure has already been allocated. The
devm_request_region function should be used to help simplify the cleanup
code and reduce the possible points of failure.
Signed-off-by: NWilliam Breathitt Gray <vilhelm.gray@gmail.com>
Reviewed-by: NAlexandre Courbot <acourbot@nvidia.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

By the time request_region is called in the ACCES 104-IDI-48 GPIO
driver, a corresponding device structure has already been allocated. The
devm_request_region function should be used to help simplify the cleanup
code and reduce the possible points of failure.
Signed-off-by: NWilliam Breathitt Gray <vilhelm.gray@gmail.com>
Reviewed-by: NAlexandre Courbot <acourbot@nvidia.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

By the time request_region is called in the ACCES 104-DIO-48E GPIO
driver, a corresponding device structure has already been allocated. The
devm_request_region function should be used to help simplify the cleanup
code and reduce the possible points of failure.
Signed-off-by: NWilliam Breathitt Gray <vilhelm.gray@gmail.com>
Reviewed-by: NAlexandre Courbot <acourbot@nvidia.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

The GPIO driver copyright boilerplate lacks the "or
later" verbiage regarding GPL compliant distribution. The MODULE_LICENSE
string should reflect the actual copyright license terms used.
Signed-off-by: NWilliam Breathitt Gray <vilhelm.gray@gmail.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>