Add a hardirq handler to the GPIO userspace event loop, making
sure to pick up the timestamp there, as close as possible in time
relative to the actual event causing the interrupt.

Tested with a simple pushbutton GPIO on ux500 and seems to work
fine.

Cc: Bartosz Golaszewski <brgl@bgdev.pl>
Reviewed-by: NFelipe Balbi <felipe.balbi@linux.intel.com>
Reported-by: NFelipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

The GPIO event descriptor was leaking kernel stack to
userspace because we don't zero the variable before
use. Ooops. Fix this.

Cc: stable@vger.kernel.org
Reported-by: NArnd Bergmann <arnd@arndb.de>
Reviewed-by: NBartosz Golaszewski <brgl@bgdev.pl>
Reviewed-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

The initialized value stored in pointer desc is never read as it
is updated in the first executable statement in the function.
This is therefore redundant and can be removed.

Cleans up clang warning:
drivers/gpio/gpiolib.c:3710:20: warning: Value stored to 'desc'
during its initialization is never read
Signed-off-by: NColin Ian King <colin.king@canonical.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Some calls to of_get_named_gpio() calls sets the flags
argument to NULL because they are not interested in the
flags. This caused a null pointer exception since we were
unconditionally using these flags. Fix it.

Fixes: 6a537d48 ("gpio: of: Support regulator nonstandard GPIO properties")
Cc: Heiner Kallweit <hkallweit1@gmail.com>
Reported-by: NHeiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

The local variable "irq" will eventually be set to an appropriate value
a bit later. Thus omit the explicit initialisation at the beginning.
Signed-off-by: NMarkus Elfring <elfring@users.sourceforge.net>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Move the assignment for the local variable "irq" so that its setting
will only be performed directly before it is checked by this function.
Signed-off-by: NMarkus Elfring <elfring@users.sourceforge.net>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Replace the specification of a data structure by a pointer dereference
as the parameter for the operator "sizeof" to make the corresponding size
determination a bit safer according to the Linux coding style convention.

This issue was detected by using the Coccinelle software.
Signed-off-by: NMarkus Elfring <elfring@users.sourceforge.net>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

A single character (line break) should be put into a sequence.
Thus use the corresponding function "seq_putc".

This issue was detected by using the Coccinelle software.
Signed-off-by: NMarkus Elfring <elfring@users.sourceforge.net>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Sometimes a GPIO is fetched with NULL as parent device, and
that is just fine. So under these circumstances, avoid using
dev_name() to provide a name for the GPIO line.
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Move the workaround from stmpe_gpio_irq_unmask() which is executed
in atomic context to stmpe_gpio_irq_sync_unlock() which is not.

It fixes the following issue:

[    1.500000] BUG: scheduling while atomic: swapper/1/0x00000002
[    1.500000] CPU: 0 PID: 1 Comm: swapper Not tainted 4.15.0-rc2-00020-gbd4301f-dirty #28
[    1.520000] Hardware name: STM32 (Device Tree Support)
[    1.520000] [<0000bfc9>] (unwind_backtrace) from [<0000b347>] (show_stack+0xb/0xc)
[    1.530000] [<0000b347>] (show_stack) from [<0001fc49>] (__schedule_bug+0x39/0x58)
[    1.530000] [<0001fc49>] (__schedule_bug) from [<00168211>] (__schedule+0x23/0x2b2)
[    1.550000] [<00168211>] (__schedule) from [<001684f7>] (schedule+0x57/0x64)
[    1.550000] [<001684f7>] (schedule) from [<0016a513>] (schedule_timeout+0x137/0x164)
[    1.550000] [<0016a513>] (schedule_timeout) from [<00168b91>] (wait_for_common+0x8d/0xfc)
[    1.570000] [<00168b91>] (wait_for_common) from [<00139753>] (stm32f4_i2c_xfer+0xe9/0xfe)
[    1.580000] [<00139753>] (stm32f4_i2c_xfer) from [<00138545>] (__i2c_transfer+0x111/0x148)
[    1.590000] [<00138545>] (__i2c_transfer) from [<001385cf>] (i2c_transfer+0x53/0x70)
[    1.590000] [<001385cf>] (i2c_transfer) from [<001388a5>] (i2c_smbus_xfer+0x12f/0x36e)
[    1.600000] [<001388a5>] (i2c_smbus_xfer) from [<00138b49>] (i2c_smbus_read_byte_data+0x1f/0x2a)
[    1.610000] [<00138b49>] (i2c_smbus_read_byte_data) from [<00124fdd>] (__stmpe_reg_read+0xd/0x24)
[    1.620000] [<00124fdd>] (__stmpe_reg_read) from [<001252b3>] (stmpe_reg_read+0x19/0x24)
[    1.630000] [<001252b3>] (stmpe_reg_read) from [<0002c4d1>] (unmask_irq+0x17/0x22)
[    1.640000] [<0002c4d1>] (unmask_irq) from [<0002c57f>] (irq_startup+0x6f/0x78)
[    1.650000] [<0002c57f>] (irq_startup) from [<0002b7a1>] (__setup_irq+0x319/0x47c)
[    1.650000] [<0002b7a1>] (__setup_irq) from [<0002bad3>] (request_threaded_irq+0x6b/0xe8)
[    1.660000] [<0002bad3>] (request_threaded_irq) from [<0002d0b9>] (devm_request_threaded_irq+0x3b/0x6a)
[    1.670000] [<0002d0b9>] (devm_request_threaded_irq) from [<001446e7>] (mmc_gpiod_request_cd_irq+0x49/0x8a)
[    1.680000] [<001446e7>] (mmc_gpiod_request_cd_irq) from [<0013d45d>] (mmc_start_host+0x49/0x60)
[    1.690000] [<0013d45d>] (mmc_start_host) from [<0013e40b>] (mmc_add_host+0x3b/0x54)
[    1.700000] [<0013e40b>] (mmc_add_host) from [<00148119>] (mmci_probe+0x4d1/0x60c)
[    1.710000] [<00148119>] (mmci_probe) from [<000f903b>] (amba_probe+0x7b/0xbe)
[    1.720000] [<000f903b>] (amba_probe) from [<001170e5>] (driver_probe_device+0x169/0x1f8)
[    1.730000] [<001170e5>] (driver_probe_device) from [<001171b7>] (__driver_attach+0x43/0x5c)
[    1.740000] [<001171b7>] (__driver_attach) from [<0011618d>] (bus_for_each_dev+0x3d/0x46)
[    1.740000] [<0011618d>] (bus_for_each_dev) from [<001165cd>] (bus_add_driver+0xcd/0x124)
[    1.740000] [<001165cd>] (bus_add_driver) from [<00117713>] (driver_register+0x4d/0x7a)
[    1.760000] [<00117713>] (driver_register) from [<001fc765>] (do_one_initcall+0xbd/0xe8)
[    1.770000] [<001fc765>] (do_one_initcall) from [<001fc88b>] (kernel_init_freeable+0xfb/0x134)
[    1.780000] [<001fc88b>] (kernel_init_freeable) from [<00167ee3>] (kernel_init+0x7/0x9c)
[    1.790000] [<00167ee3>] (kernel_init) from [<00009b65>] (ret_from_fork+0x11/0x2c)

Cc: stable@vger.kernel.org
Signed-off-by: NAlexandre TORGUE <alexandre.torgue@st.com>
Signed-off-by: NPatrice Chotard <patrice.chotard@st.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

This driver has no business including <linux/gpio.h>, it is a
driver so include <linux/gpio/driver.h>.
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

These drivers has no business including <linux/gpio.h>, they
are drivers so include <linux/gpio/driver.h>.
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

This driver has no business including <linux/gpio.h>, it is a
driver so include <linux/gpio/driver.h>.
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

This driver has no business including <linux/gpio.h>, it is a
driver so include <linux/gpio/driver.h>.
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

This driver has no business including <linux/gpio.h>, it is a
driver so include <linux/gpio/driver.h>.
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

This driver has no business including <linux/gpio.h>, it is a
driver so include <linux/gpio/driver.h>.

GPIOF_DIR_IN/GPIOF_DIR_OUT are for consumers and should not be
used in drivers to use just 1/0 instead.
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

This driver has no business including <linux/gpio.h>, it is a
driver so include <linux/gpio/driver.h>.
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

This driver has no business including <linux/gpio.h>, it is a
driver so include <linux/gpio/driver.h>.
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

This is a GPIO driver so it should definately include
<linux/gpio/driver.h>. We want to get rid of <linux/of_gpio.h>
but that will take a bit longer.
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

This driver has no business including <linux/gpio.h>, it is a
driver so include <linux/gpio/driver.h>.
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

This driver has no business including <linux/gpio.h>, it is a
driver so include <linux/gpio/driver.h>.
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

This driver has no business including <linux/gpio.h> or
<linux/of_gpio.h>. Cut them and include <linux/gpio/driver.h>
and <linux/gpio/consumer.h> which is it they really needs.
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

While most GPIOs are indicated to be active low or open drain using
their twocell flags, we have legacy regulator bindings to take into
account.

Add a quirk respecting the special boolean active-high and open
drain flags when parsing regulator nodes for GPIOs.

This makes it possible to get rid of duplicated inversion semantics
handling in the regulator core and any regulator drivers parsing
and handling this separately.

Unfortunately the old regulator inversion semantics are specified
such that the presence or absence of "enable-active-high" solely
controls the semantics, so we cannot deprecate this in favor
of the phandle-provided inversion flag, instead any such phandle
inversion flag provided in the second cell of a GPIO handle must be
actively ignored, so we print a warning to contain the situation
and make things easy for the users.
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

We have been holding back on adding an API for fetching GPIO handles
directly from device nodes, strongly preferring to get it from the
spawn devices instead.

The fwnode interface however already contains an API for doing this,
as it is used for opaque device tree nodes or ACPI nodes for getting
handles to LEDs and keys that use GPIO: those are specified as one
child per LED/key in the device tree and are not individual devices.

However regulators present a special problem as they already have
helper functions to traverse the device tree from a regulator node
and two levels down to fill in data, and as it already traverses
GPIO nodes in its own way, and already holds a pointer to each
regulators device tree node, it makes most sense to export an
API to fetch the GPIO descriptor directly from the node.

We only support the devm_* version for now, hopefully no non-devres
version will be needed.
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Sometimes a GPIO needs to be taken from a node without
a device associated with it. The fwnode accessor does this,
let's however break out the DT code for now.
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Before it was clearly established that all GPIO properties in the
device tree shall be named "foo-gpios" (with the deprecated variant
"foo-gpio" for single lines) we unfortunately merged a few bindings
for regulators with random phandle names.

As we want to switch the GPIO regulator driver to using descriptors,
we need devm_gpiod_get() to return something reasonable when looking
up these in the device tree.

Put in a special #ifdef:ed kludge to do this special lookup only
for the regulator case and gets compiled out if we're not enabling
regulators. Supply a whitelist with properties we accept.

Cc: Rob Herring <robh@kernel.org>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Fix to return error code -ENOMEM from the error handling
case instead of 0, as done elsewhere in this function.

Fixes: 5a2a3002 ("gpio: Add gpio driver support for ThunderX and OCTEON-TX")
Signed-off-by: NWei Yongjun <weiyongjun1@huawei.com>
Acked-by: NDavid Daney <david.daney@cavium.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

The newly added GPIO driver for winbond chipsets causes a
circular dependency warning in Kconfig:

drivers/gpio/Kconfig:13:error: recursive dependency detected!
drivers/gpio/Kconfig:13:	symbol GPIOLIB is selected by STX104
drivers/iio/adc/Kconfig:699:	symbol STX104 depends on ISA_BUS_API
arch/Kconfig:830:	symbol ISA_BUS_API is selected by GPIO_WINBOND
drivers/gpio/Kconfig:701:	symbol GPIO_WINBOND depends on GPIOLIB

The underlying problem is that ISA_BUS_API is not meant to be selected by
device drivers, instead it is provided by the architectures that support
ISA add-on card devices, or in case of x86 have this explicitly enabled.

This particular driver appears to be different from the other ISA_BUS_API
based drivers, in that it is not normally an add-on card (ISA or PC104)
but instead is an LPC-attached component on the mainboard. We already
support other functionality provided by this chip, at least
drivers/watchdog/w83627hf_wdt.c and drivers/hwmon/w83627ehf.c, plus
there is a discovery function for this hardware in
drivers/parport/parport_pc.c.

If we want to use this driver without having to enable CONFIG_EXPERT,
it might be better to not use the isa_bus_type for it, but rather
turn it into a platform_driver, acpi_driver or add an MFD for it that
is shared with the wdt and hwmon portions and does the probing.

For now, this patch fixes the dependency by changing 'select' into
'depends on'.

Cc: William Breathitt Gray <vilhelm.gray@gmail.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Maciej S. Szmigiero <mail@maciej.szmigiero.name>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Fixes: a0d65009 ("gpio: winbond: Add driver")
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

The ACCES PCIe-IDIO-24 device provides 56 lines of digital I/O (24 lines
of optically-isolated non-polarized digital inputs for AC and DC control
signals, 24 lines of isolated solid state FET digital outputs, and 8
non-isolated TTL/CMOS compatible programmable I/O). An interrupt is
generated when any of the inputs change state (low to high or high to
low).

Input filter control is not supported by this driver, and input filters
are deactivated by this driver. These devices are capable of
get_multiple and set_multiple functionality, but these functions have
not yet been implemented for this driver. Change-Of-State (COS)
detection functionality may be configured to fire interrupts on
exclusively rising/falling edges, but this driver currently only
implements COS detection for either both edges or none.
Signed-off-by: NWilliam Breathitt Gray <vilhelm.gray@gmail.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Some pinctrl drivers can use the gpiochip irq valid information
to figure out if certain gpios are exposed to the kernel for
usage or not. Expose this API so we can use it in the
pinmux_ops::request ops.
Signed-off-by: NStephen Boyd <sboyd@codeaurora.org>
Acked-by: NBjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

The use of the GPIOF_* flags is deprecated, so don't advertise them
here. Document the plain numbers for now until we have a better
solution.
Signed-off-by: NWolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

This commit adds GPIO driver for Winbond Super I/Os.

Currently, only W83627UHG model (also known as Nuvoton NCT6627UD)
is supported but in the future a support for other Winbond models,
too, can be added to the driver.

A module parameter "gpios" sets a bitmask of GPIO ports to enable
(bit 0 is GPIO1, bit 1 is GPIO2, etc.).

One should be careful which ports one tinkers with since some
might be managed by the firmware (for functions like powering on and
off, sleeping, BIOS recovery, etc.) and some of GPIO port pins are
physically shared with other devices included in the Super I/O chip.
Signed-off-by: NMaciej S. Szmigiero <mail@maciej.szmigiero.name>
Reviewed-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Before it was clearly established that all GPIO properties in the
device tree shall be named "foo-gpios" (with the deprecated variant
"foo-gpio" for single lines) we unfortunately merged a few bindings
which named the lines "gpio-foo" instead.

This is most prominent in the GPIO SPI driver in Linux which names
the lines "gpio-sck", "gpio-mosi" and "gpio-miso".

As we want to switch the GPIO SPI driver to using descriptors, we
need devm_gpiod_get() to return something reasonable when looking
up these in the device tree.

Put in a special #ifdef:ed kludge to do this special lookup only
for the SPI case and gets compiled out if we're not enabling SPI.
If we have more oddly defined legacy GPIOs like this, they can be
handled in a similar manner.
Reviewed-by: NRob Herring <robh@kernel.org>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Some GPIO lines appear named "?" in the lsgpio dump due to their
requesting drivers not passing a reasonable label.

Most typically this happens if a device tree node just defines
gpios = <...> and not foo-gpios = <...>, the former gets named
"foo" and the latter gets named "?".

However the struct device passed in is always valid so let's
just label the GPIO with dev_name() on the device if no proper
label was passed.

Cc: Reported-by: Jason Kridner <jkridner@beagleboard.org>
Reported-by: NJason Kridner <jkridner@beagleboard.org>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

As we need to add GPIO lookup tables to the OMAP platforms, we
need to reference each GPIO chip with a unique label. Use the GPIO
base to name each chip, "gpio-0-31", "gpio-32-63" etc.

Cc: Grygorii Strashko <grygorii.strashko@ti.com>
Cc: Santosh Shilimkar <ssantosh@kernel.org>
Cc: Kevin Hilman <khilman@kernel.org>
Cc: linux-omap@vger.kernel.org
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

The gpiod_set_transitory() function is publicly exported, and
it is expected from it to be ready for usage with optional GPIOs
on consumer's side.
Signed-off-by: NVladimir Zapolskiy <vz@mleia.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

This non-functional change slightly simplifies the implementation
of gpiod_to_chip() function.
Signed-off-by: NVladimir Zapolskiy <vz@mleia.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

The fix restores a proper validation of an input gpio desc, which
might be needed to deal with optional GPIOs correctly.

Fixes: 02e47980 ("gpio: Alter semantics of *raw* operations to actually be raw")
Signed-off-by: NVladimir Zapolskiy <vz@mleia.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

The test should be >= ARRAY_SIZE() instead of > ARRAY_SIZE().
Signed-off-by: NVasyl Gomonovych <gomonovych@gmail.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

This reverts commit 93ebe863.

After discussion and review of the v11 patchset, a new approach
was found so that this patch is not needed.
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>