Use named item instead of plain integer for enum gpiod_flags
to make it clear that even 0 has its own meaning.

Cc: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NBartosz Golaszewski <bgolaszewski@baylibre.com>

The line.eflags field is shared so document this fact and highlight it
throughout using READ_ONCE() and WRITE_ONCE() accessors.

Also use a local copy of the eflags in edge_irq_thread() to ensure
consistent control flow even if eflags changes.  This is only a defensive
measure as edge_irq_thread() is currently disabled when the eflags are
changed.
Signed-off-by: NKent Gibson <warthog618@gmail.com>
Signed-off-by: NBartosz Golaszewski <bgolaszewski@baylibre.com>

Several places in the code are using same idiom, i.e.
	IS_ERR(desc) && PTR_ERR(desc) == -ENOENT
which meaning is GPIO description is not found.

For better readability extract gpiod_not_found() helper and use it.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NBartosz Golaszewski <bgolaszewski@baylibre.com>

Make the tegra186 GPIO driver resistent to variable depth
interrupt hierarchy, which we are about to introduce.

No functionnal change yet.
Signed-off-by: NMarc Zyngier <maz@kernel.org>

The dev_t is defined in types.h while struct gpio_device forward declaration
is missed. Take into account above and update header block in gpiolib-cdev.h.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20201005095622.73616-1-andriy.shevchenko@linux.intel.comSigned-off-by: NLinus Walleij <linus.walleij@linaro.org>

Use kstrndup() to copy line labels from the userspace provided char
array, rather than ensuring the char array contains a null terminator
and using kstrdup().

Note that the length provided to kstrndup() still assumes that the char
array does contain a null terminator, so the maximum string length is one
less than the array.  This is consistent with the previous behaviour.
Suggested-by: NAndy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: NKent Gibson <warthog618@gmail.com>
Link: https://lore.kernel.org/r/20201005070246.20927-1-warthog618@gmail.comSigned-off-by: NLinus Walleij <linus.walleij@linaro.org>

The pca953x driver never checks the result of irq_find_mapping(),
which returns 0 when no mapping is found. When a spurious interrupt
is delivered (which can happen under obscure circumstances), the
kernel explodes as it still tries to handle the error code as
a real interrupt.

Handle this particular case and warn on spurious interrupts.
Signed-off-by: NMarc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20201005140217.1390851-1-maz@kernel.orgSigned-off-by: NLinus Walleij <linus.walleij@linaro.org>

It appears that UML (arch/um) has no compat.h header defined and hence
can't compile a recently provided piece of code in GPIO library.

Disable compat ->read() code in UML case to avoid compilation errors.

While at it, use pattern which is already being used in the kernel elsewhere.

Fixes: 5ad284ab ("gpiolib: Fix line event handling in syscall compatible mode")
Reported-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20201005131044.87276-1-andriy.shevchenko@linux.intel.comSigned-off-by: NLinus Walleij <linus.walleij@linaro.org>

When driver has been converted to the bitmap API the non-bitmap functions
started behaving differently on 32-bit BE architectures since the bytes in
two consequent unsigned longs are in different order in comparison to byte
array. Hence if the chip had had more than 32 lines the memset() call over
it would have not set up upper lines correctly.
Although it's currently a theoretical case (no supported chips of this type
has 32+ lines), it's better to provide a clean code to avoid people thinking
this is okay and potentially producing not fully working things.

Fixes: 35d13d94 ("gpio: pca953x: convert to use bitmap API")
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: NBartosz Golaszewski <bgolaszewski@baylibre.com>
Link: https://lore.kernel.org/r/20200930142013.59247-2-andriy.shevchenko@linux.intel.comSigned-off-by: NLinus Walleij <linus.walleij@linaro.org>

In IRQ handler we have to clear bitmap before use. Currently
the GCC extension has been used for that. For sake of the consistency
switch to bitmap API. As expected bloat-o-meter shows no difference
in the object size.
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: NBartosz Golaszewski <bgolaszewski@baylibre.com>
Link: https://lore.kernel.org/r/20200930142013.59247-1-andriy.shevchenko@linux.intel.comSigned-off-by: NLinus Walleij <linus.walleij@linaro.org>

The NXP PCAL9554B is a variant of the PCA953x GPIO expander,
with 8 GPIOs, latched interrupts and some advanced configuration
options. The "C" version only differs in I2C address.
Signed-off-by: NMike Looijmans <mike.looijmans@topic.nl>
Reviewed-by: NBartosz Golaszewski <bgolaszewski@baylibre.com>
Link: https://lore.kernel.org/r/20200930092053.2114-2-mike.looijmans@topic.nlSigned-off-by: NLinus Walleij <linus.walleij@linaro.org>

Add support for setting debounce on a line via the GPIO uAPI.
Where debounce is not supported by hardware, a software debounce is
provided.

The implementation of the software debouncer waits for the line to be
stable for the debounce period before determining if a level change,
and a corresponding edge event, has occurred.  This provides maximum
protection against glitches, but also introduces a debounce_period
latency to edge events.

The software debouncer is integrated with the edge detection as it
utilises the line interrupt, and integration is simpler than getting
the two to interwork.  Where software debounce AND edge detection is
required, the debouncer provides both.
Signed-off-by: NKent Gibson <warthog618@gmail.com>
Signed-off-by: NBartosz Golaszewski <bgolaszewski@baylibre.com>

Add support for the GPIO_V2_LINE_SET_VALUES_IOCTL.
Signed-off-by: NKent Gibson <warthog618@gmail.com>
Signed-off-by: NBartosz Golaszewski <bgolaszewski@baylibre.com>

Add support for GPIO_V2_LINE_SET_CONFIG_IOCTL, the uAPI v2
line set config ioctl.
Signed-off-by: NKent Gibson <warthog618@gmail.com>
Signed-off-by: NBartosz Golaszewski <bgolaszewski@baylibre.com>

Add support for edge detection to lines requested using
GPIO_V2_GET_LINE_IOCTL.

The edge_detector implementation is based on the v1 lineevent
implementation.  Unlike the v1 implementation, an overflow of the event
buffer results in discarding older events, rather than the most
recent, so the final event in a burst will correspond to the current
state of the line.
Signed-off-by: NKent Gibson <warthog618@gmail.com>
Signed-off-by: NBartosz Golaszewski <bgolaszewski@baylibre.com>

Add support for GPIO_V2_GET_LINEINFO_IOCTL and
GPIO_V2_GET_LINEINFO_WATCH_IOCTL.

The core of this change is the event kfifo switching to contain
struct gpioline_info_changed_v2, instead of v1 as v2 is richer.

The two uAPI versions are mostly independent - other than where they both
provide line info changes via reads on the chip fd.  As the info change
structs differ between v1 and v2, the infowatch implementation tracks which
version of the infowatch ioctl, either GPIO_GET_LINEINFO_WATCH_IOCTL or
GPIO_V2_GET_LINEINFO_WATCH_IOCTL, initiates the initial watch and returns
the corresponding info change struct to the read.  The version supported
on that fd locks to that version on the first watch request, so subsequent
watches from that process must use the same uAPI version.
Signed-off-by: NKent Gibson <warthog618@gmail.com>
Signed-off-by: NBartosz Golaszewski <bgolaszewski@baylibre.com>

Add support for requesting lines using the GPIO_V2_GET_LINE_IOCTL, and
returning their current values using GPIO_V2_LINE_GET_VALUES_IOCTL.

The struct linereq implementation is based on the v1 struct linehandle
implementation.
Signed-off-by: NKent Gibson <warthog618@gmail.com>
Signed-off-by: NBartosz Golaszewski <bgolaszewski@baylibre.com>

Add a build option to allow the removal of the CDEV v1 ABI.
Suggested-by: NBartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: NKent Gibson <warthog618@gmail.com>
Reviewed-by: NAndy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: NBartosz Golaszewski <bgolaszewski@baylibre.com>

Make the gpiolib-cdev module a build option.  This allows the CDEV
interface to be removed from the kernel to reduce kernel size in
applications where is it not required, and provides the parent for
other CDEV interface specific build options to follow.
Suggested-by: NBartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: NKent Gibson <warthog618@gmail.com>
Reviewed-by: NAndy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: NBartosz Golaszewski <bgolaszewski@baylibre.com>

Replace usage of strncpy() with strscpy() to remove -Wstringop-truncation
warnings.

The structures being populated are zeroed, to prevent stack leakage as
they are returned to userspace, so strscpy() performs the equivalent
function without the warnings.
Reported-by: Nkernel test robot <lkp@intel.com>
Signed-off-by: NKent Gibson <warthog618@gmail.com>
Reviewed-by: NAndy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: NBartosz Golaszewski <bgolaszewski@baylibre.com>

Set the value of the line info offset in gpio_desc_to_lineinfo(), rather
than relying on it being passed in the info.  This makes the function
behave as you would expect from the name - it generates the line info
corresponding to a given GPIO desc.
Signed-off-by: NKent Gibson <warthog618@gmail.com>
Reviewed-by: NAndy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: NBartosz Golaszewski <bgolaszewski@baylibre.com>

Let's move the code preparing the device properties into a separate
routine. This has the advantage of simplifying the error handling and
makes the indentation less deep.
Signed-off-by: NBartosz Golaszewski <bgolaszewski@baylibre.com>
Reviewed-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>

GPIO line names are currently created by the driver from the chip label.
We'll want to support custom formats for line names (for instance: to
name all lines the same) for user-space tests so create them in the
module init function and pass them to the driver using the standard
'gpio-line-names' property.
Signed-off-by: NBartosz Golaszewski <bgolaszewski@baylibre.com>
Reviewed-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>

While we do check the "chip-name" property in probe(), we never actually
use it. Let's pass the chip label to the driver using device properties
as we'll want to allow users to define their own once dynamically
created chips are supported.

The property is renamed to "chip-label" to not cause any confusion with
the actual chip name which is of the form: "gpiochipX".

If the "chip-label" property is missing, let's do what most devices in
drivers/gpio/ do and use dev_name().
Signed-off-by: NBartosz Golaszewski <bgolaszewski@baylibre.com>
Reviewed-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>

The driver actually supports 4 properties but we only ever set up up to
three. This will change however in upcoming patches so increase the
number of really (as in: the number the property array can hold)
supported properties to 4.
Reported-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NBartosz Golaszewski <bgolaszewski@baylibre.com>
Reviewed-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>

There's a return; at the end of a void function. This is not needed so
remove it.
Signed-off-by: NBartosz Golaszewski <bgolaszewski@baylibre.com>
Reviewed-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>

We don't need a custom logging helper. Let's use the standard pr_fmt()
macro which allows us to use all pr_*() routines with custom format.
Signed-off-by: NBartosz Golaszewski <bgolaszewski@baylibre.com>
Reviewed-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>

Drop the definition for the driver name. Let's use KBUILD_MODNAME for
the log format and use the "gpio-mockup" value directly in the only
place where it's relevant: in the name of the device.
Signed-off-by: NBartosz Golaszewski <bgolaszewski@baylibre.com>
Reviewed-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>

This module doesn't need gpio/consumer.h - it's a provider. It also
doesn't use any symbols from init.h so let's remove both includes.
Signed-off-by: NBartosz Golaszewski <bgolaszewski@baylibre.com>
Reviewed-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>

Some Layerscape/QoriQ SoCs have input buffers which needs to be enabled
first. This was done in two different ways in the driver. Unify it.

This was tested on a LS1028A SoC.
Signed-off-by: NMichael Walle <michael@walle.cc>
Signed-off-by: NBartosz Golaszewski <bgolaszewski@baylibre.com>

If the module init function fails after creating the debugs directory,
it's never removed. Add proper cleanup calls to avoid this resource
leak.

Fixes: 9202ba23 ("gpio: mockup: implement event injecting over debugfs")
Cc: <stable@vger.kernel.org>
Signed-off-by: NBartosz Golaszewski <bgolaszewski@baylibre.com>
Reviewed-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>

Change config to tristate, add module device table, module author,
description and license to support module build for i.MX GPIO driver.

As this is a SoC GPIO module, it provides common functions for most
of the peripheral devices, such as GPIO pins control, secondary
interrupt controller for GPIO pins IRQ etc., without GPIO driver, most
of the peripheral devices will NOT work properly, so GPIO module is
similar with clock, pinctrl driver that should be loaded ONCE and
never unloaded.

Since MXC GPIO driver needs to have init function to register syscore
ops once, here still use subsys_initcall(), NOT module_platform_driver().
Signed-off-by: NAnson Huang <Anson.Huang@nxp.com>
Link: https://lore.kernel.org/r/1600320829-1453-1-git-send-email-Anson.Huang@nxp.comSigned-off-by: NLinus Walleij <linus.walleij@linaro.org>

The original commit appears to have the logic reversed in
amd_fch_gpio_get_direction. Also confirmed by observing the value of
"direction" in the sys tree.
Signed-off-by: NEd Wildgoose <lists@wildgooses.com>
Fixes: e09d168f ("gpio: AMD G-Series PCH gpio driver")
Cc: stable@vger.kernel.org
Signed-off-by: NBartosz Golaszewski <bgolaszewski@baylibre.com>

GPIO_U is mapped to the least significant byte of input/output mask, and
the byte in "output" mask should be 0 because GPIO_U is input only. All
the other bits need to be 1 because GPIO_V/W/X support both input and
output modes.

Similarly, GPIO_Y/Z are mapped to the 2 least significant bytes, and the
according bits need to be 1 because GPIO_Y/Z support both input and
output modes.

Fixes: ab4a8553 ("gpio: aspeed: Add in ast2600 details to Aspeed driver")
Signed-off-by: NTao Ren <rentao.bupt@gmail.com>
Reviewed-by: NAndrew Jeffery <andrew@aj.id.au>
Signed-off-by: NBartosz Golaszewski <bgolaszewski@baylibre.com>

Currently, the IRQ setup for the SGPIO driver enables all interrupts in
dual-edge trigger mode. Since the default handler is handle_bad_irq, any
state change on input GPIOs will trigger bad IRQ warnings.

This change applies sensible IRQ defaults: single-edge trigger, and all
IRQs disabled.
Signed-off-by: NJeremy Kerr <jk@codeconstruct.com.au>
Fixes: 7db47faa ("gpio: aspeed: Add SGPIO driver")
Reviewed-by: NJoel Stanley <joel@jms.id.au>
Acked-by: NAndrew Jeffery <andrew@aj.id.au>
Signed-off-by: NBartosz Golaszewski <bgolaszewski@baylibre.com>

Currently, the aspeed-sgpio driver exposes up to 80 GPIO lines,
corresponding to the 80 status bits available in hardware. Each of these
lines can be configured as either an input or an output.

However, each of these GPIOs is actually an input *and* an output; we
actually have 80 inputs plus 80 outputs.

This change expands the maximum number of GPIOs to 160; the lower half
of this range are the input-only GPIOs, the upper half are the outputs.
We fix the GPIO directions to correspond to this mapping.

This also fixes a bug when setting GPIOs - we were reading from the
input register, making it impossible to set more than one output GPIO.
Signed-off-by: NJeremy Kerr <jk@codeconstruct.com.au>
Fixes: 7db47faa ("gpio: aspeed: Add SGPIO driver")
Reviewed-by: NJoel Stanley <joel@jms.id.au>
Reviewed-by: NAndrew Jeffery <andrew@aj.id.au>
Acked-by: NRob Herring <robh@kernel.org>
Signed-off-by: NBartosz Golaszewski <bgolaszewski@baylibre.com>

When pca953x_irq_pending returns false, the pending parameter won't
be set. But pca953x_irq_handler continues using this uninitialized
variable as pending irqs and will cause problem.
Fix the issue by initializing pending to 0.

Fixes: 064c73af ("gpio: pca953x: Synchronize interrupt handler properly")
Signed-off-by: NYe Li <ye.li@nxp.com>
Reviewed-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NBartosz Golaszewski <bgolaszewski@baylibre.com>

Add support for the GPIO controller of the sl28 board management
controller. This driver is part of a multi-function device.

A controller has 8 lines. There are three different flavors:
full-featured GPIO with interrupt support, input-only and output-only.
Signed-off-by: NMichael Walle <michael@walle.cc>
Reviewed-by: NLinus Walleij <linus.walleij@linaro.org>
Reviewed-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NLee Jones <lee.jones@linaro.org>

It's possible for a GPIO chip to not have a parent device (whose
properties we inspect for 'gpio-line-names'). In this case we should
simply return from devprop_gpiochip_set_names(). Add an appropriate
check for this use-case.

Fixes: 7cba1a4d ("gpiolib: generalize devprop_gpiochip_set_names() for device properties")
Reported-by: NAnders Roxell <anders.roxell@linaro.org>
Signed-off-by: NBartosz Golaszewski <bgolaszewski@baylibre.com>
Reviewed-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Tested-by: NAnders Roxell <anders.roxell@linaro.org>
Reviewed-by: NMika Westerberg <mika.westerberg@linux.intel.com>

The introduced line event handling ABI in the commit

  61f922db ("gpio: userspace ABI for reading GPIO line events")

missed the fact that 64-bit kernel may serve for 32-bit applications.
In such case the very first check in the lineevent_read() will fail
due to alignment differences.

To workaround this introduce lineevent_get_size() helper which returns actual
size of the structure in user space.

Fixes: 61f922db ("gpio: userspace ABI for reading GPIO line events")
Suggested-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: NArnd Bergmann <arnd@arndb.de>
Tested-by: NKent Gibson <warthog618@gmail.com>
Signed-off-by: NBartosz Golaszewski <bgolaszewski@baylibre.com>