There's now a new ReST file. Add it to the index.rst file.

Fixes: ce7a2f77 ("docs: gpio: Add GPIO Aggregator documentation")
Fixes: 2fd1abe9 ("Documentation: gpio: add documentation for gpio-mockup")
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Acked-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Link: https://lore.kernel.org/r/bad4d85c218d59c1bf69157df8e1012577680d88.1601616399.git.mchehab+huawei@kernel.orgSigned-off-by: Linus 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: Mike Looijmans <mike.looijmans@topic.nl>
Reviewed-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Link: https://lore.kernel.org/r/20200930092053.2114-2-mike.looijmans@topic.nlSigned-off-by: Linus Walleij <linus.walleij@linaro.org>

Merge tag 'gpio-updates-for-v5.10-part2' of git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux into devel

gpio updates for v5.10 - part 2

- refactor gpio-mockup testing module
- simplify the code in gpio-mpc8xxx
- implement v2 of the GPIO user API

Add support for debouncing monitored lines to gpio-event-mon.
Signed-off-by: Kent Gibson <warthog618@gmail.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>

Extend gpio-event-mon to support monitoring multiple lines.
This would require multiple lineevent requests to implement using uAPI v1,
but can be performed with a single line request using uAPI v2.
Signed-off-by: Kent Gibson <warthog618@gmail.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>

Port the gpio-event-mon tool to the latest GPIO uAPI.
Signed-off-by: Kent Gibson <warthog618@gmail.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>

Port the gpio-hammer tool to the latest GPIO uAPI.
Signed-off-by: Kent Gibson <warthog618@gmail.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>

Rename nlines to num_lines to be consistent with other usage for fields
describing the number of entries in an array.
Signed-off-by: Kent Gibson <warthog618@gmail.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>

Port the gpio-watch tool to the latest GPIO uAPI.
Signed-off-by: Kent Gibson <warthog618@gmail.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>

Port the lsgpio tool to the latest GPIO uAPI.
Signed-off-by: Kent Gibson <warthog618@gmail.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>

Update uAPI documentation to deprecate v1 structs and ioctls.
Signed-off-by: Kent Gibson <warthog618@gmail.com>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>

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: Kent Gibson <warthog618@gmail.com>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>

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

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

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

Add a new version of the uAPI to address existing 32/64-bit alignment
issues, add support for debounce and event sequence numbers, allow
requested lines with different configurations, and provide some future
proofing by adding padding reserved for future use.

The alignment issue relates to the gpioevent_data, which packs to different
sizes on 32-bit and 64-bit platforms. That creates problems for 32-bit apps
running on 64-bit kernels.  uAPI v2 addresses that particular issue, and
the problem more generally, by adding pad fields that explicitly pad
structs out to 64-bit boundaries, so they will pack to the same size now,
and even if some of the reserved padding is used for __u64 fields in the
future.

The new structs have been analysed with pahole to ensure that they
are sized as expected and contain no implicit padding.

The lack of future proofing in v1 makes it impossible to, for example,
add the debounce feature that is included in v2.
The future proofing is addressed by providing configurable attributes in
line config and reserved padding in all structs for future features.
Specifically, the line request, config, info, info_changed and event
structs receive updated versions and new ioctls.

As the majority of the structs and ioctls were being replaced, it is
opportune to rework some of the other aspects of the uAPI:

v1 has three different flags fields, each with their own separate
bit definitions.  In v2 that is collapsed to one - gpio_v2_line_flag.

The handle and event requests are merged into a single request, the line
request, as the two requests were mostly the same other than the edge
detection provided by event requests.  As a byproduct, the v2 uAPI allows
for multiple lines producing edge events on the same line handle.
This is a new capability as v1 only supports a single line in an event
request.

As a consequence, there are now only two types of file handle to be
concerned with, the chip and the line, and it is clearer which ioctls
apply to which type of handle.

There is also some minor renaming of fields for consistency compared to
their v1 counterparts, e.g. offset rather than lineoffset or line_offset,
and consumer rather than consumer_label.

Additionally, v1 GPIOHANDLES_MAX becomes GPIO_V2_LINES_MAX in v2 for
clarity, and the gpiohandle_data __u8 array becomes a bitmap in
gpio_v2_line_values.

The v2 uAPI is mostly a reorganisation and extension of v1, so userspace
code, particularly libgpiod, should readily port to it.
Signed-off-by: Kent Gibson <warthog618@gmail.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>

Replace constant array sizes with a macro constant to clarify the source
of array sizes, provide a place to document any constraints on the size,
and to simplify array sizing in userspace if constructing structs
from their composite fields.
Signed-off-by: Kent Gibson <warthog618@gmail.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Bartosz 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: kernel test robot <lkp@intel.com>
Signed-off-by: Kent Gibson <warthog618@gmail.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Bartosz 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: Kent Gibson <warthog618@gmail.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Bartosz 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: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Reviewed-by: Andy 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: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Reviewed-by: Andy 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: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Reviewed-by: Andy 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: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Reviewed-by: Andy 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: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Reviewed-by: Andy 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: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Reviewed-by: Andy 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: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Reviewed-by: Andy 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: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>

There's some documentation for gpio-mockup's debugfs interface in the
driver's source but it's not much. Add proper documentation for this
testing module.
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>

There's a common pattern of dynamically allocating an array of char
pointers and then also dynamically allocating each string in this
array. Provide a helper for freeing such a string array with one call.
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Reviewed-by: Andy 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: Michael Walle <michael@walle.cc>
Signed-off-by: Bartosz 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: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Reviewed-by: Andy 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: Anson Huang <Anson.Huang@nxp.com>
Link: https://lore.kernel.org/r/1600320829-1453-1-git-send-email-Anson.Huang@nxp.comSigned-off-by: Linus Walleij <linus.walleij@linaro.org>

When PINCTRL_BCM2835 is enabled and GPIOLIB is disabled, it results in the
following Kbuild warning:

WARNING: unmet direct dependencies detected for GPIOLIB_IRQCHIP
  Depends on [n]: GPIOLIB [=n]
  Selected by [y]:
  - PINCTRL_BCM2835 [=y] && PINCTRL [=y] && OF [=y] && (ARCH_BCM2835 [=n] || ARCH_BRCMSTB [=n] || COMPILE_TEST [=y])

The reason is that PINCTRL_BCM2835 selects GPIOLIB_IRQCHIP without
depending on or selecting GPIOLIB while GPIOLIB_IRQCHIP is subordinate to
GPIOLIB.

Honor the kconfig menu hierarchy to remove kconfig dependency warnings.

Fixes: 85ae9e51 ("pinctrl: bcm2835: switch to GPIOLIB_IRQCHIP")
Signed-off-by: Necip Fazil Yildiran <fazilyildiran@gmail.com>
Link: https://lore.kernel.org/r/20200914144025.371370-1-fazilyildiran@gmail.comSigned-off-by: Linus Walleij <linus.walleij@linaro.org>

Convert the Maxim MAX732x family of GPIO expanders bindings to device
tree schema by merging it with existing PCA95xx schema.  These are quite
similar so merging reduces duplication.
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Reviewed-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20200916155715.21009-3-krzk@kernel.orgSigned-off-by: Linus Walleij <linus.walleij@linaro.org>

Convert the NXP PCA953x family of GPIO expanders bindings to device tree
schema.
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Reviewed-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20200916155715.21009-2-krzk@kernel.orgSigned-off-by: Linus Walleij <linus.walleij@linaro.org>

Describe common "gpio-line-names" property to fix dtbs_check warnings
like:

  arch/arm/boot/dts/imx53-m53menlo.dt.yaml: gpio@53f84000:
    'gpio-line-names' does not match any of the regexes: '^(hog-[0-9]+|.+-hog(-[0-9]+)?)$', 'pinctrl-[0-9]+'
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Reviewed-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20200920195848.27075-3-krzk@kernel.orgSigned-off-by: Linus Walleij <linus.walleij@linaro.org>