The idea to create a debugfs to replace the aging and
dangerous sysfs ABI for hacking and tinkering came up
on the list.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20201204083533.65830-1-linus.walleij@linaro.org

When trying to export an nonexisting gpio ID, the kernel prints out a
big warning w/ stacktrace, sounding like a huge problem. In fact it's
a pretty normal situation, like file or device not found.

So, just print a more relaxed warning instead.

changes v2: drop defining pr_fmt()
Signed-off-by: Enrico Weigelt <info@metux.net>
Link: https://lore.kernel.org/r/20201202133754.32045-1-info@metux.netSigned-off-by: Linus Walleij <linus.walleij@linaro.org>

Add support for selecting the realtime clock for events.
Signed-off-by: Kent Gibson <warthog618@gmail.com>
Link: https://lore.kernel.org/r/20201014231158.34117-4-warthog618@gmail.comSigned-off-by: Linus Walleij <linus.walleij@linaro.org>

Add support for reporting if a line is configured to report realtime
timestamps in events.
Signed-off-by: Kent Gibson <warthog618@gmail.com>
Link: https://lore.kernel.org/r/20201014231158.34117-3-warthog618@gmail.comSigned-off-by: Linus Walleij <linus.walleij@linaro.org>

Using CLOCK_REALTIME as the source for event timestamps is crucial for
some specific applications, particularly those requiring timetamps
relative to a PTP clock, so provide an option to switch the event
timestamp source from the default CLOCK_MONOTONIC to CLOCK_REALTIME.

Note that CLOCK_REALTIME was the default source clock for GPIO until
Linux 5.7 when it was changed to CLOCK_MONOTONIC due to issues with the
shifting of the realtime clock.
Providing this option maintains the CLOCK_MONOTONIC as the default,
while also providing a path forward for those dependent on the pre-5.7
behaviour.
Suggested-by: Jack Winch <sunt.un.morcov@gmail.com>
Signed-off-by: Kent Gibson <warthog618@gmail.com>
Link: https://lore.kernel.org/r/20201014231158.34117-2-warthog618@gmail.comSigned-off-by: Linus Walleij <linus.walleij@linaro.org>

This adds a driver that supports the GPIO block found in
MStar/SigmaStar ARMv7 SoCs.

The controller seems to have enough register for 128 lines
but where they are wired up differs between chips and
no currently known chip uses anywhere near 128 lines so there
needs to be some per-chip data to collect together what lines
actually have physical pins attached and map the right names to them.

The core peripherals seem to use the same lines on the
currently known chips but the lines used for the sensor
interface, lcd controller etc pins seem to be totally
different between the infinity and mercury chips

The code tries to collect all of the re-usable names,
offsets etc together so that it's easy to build the extra
per-chip data for other chips in the future.

So far this only supports the MSC313 and MSC313E chips.

Support for the SSC8336N (mercury5) is trivial to add once
all of the lines have been mapped out.
Signed-off-by: Daniel Palmer <daniel@0x0f.com>
Link: https://lore.kernel.org/r/20201129110803.2461700-4-daniel@0x0f.comSigned-off-by: Linus Walleij <linus.walleij@linaro.org>

Add a binding description for the MStar/SigmaStar GPIO controller
found in the MSC313 and later ARMv7 SoCs.
Signed-off-by: Daniel Palmer <daniel@0x0f.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20201129110803.2461700-3-daniel@0x0f.comSigned-off-by: Linus Walleij <linus.walleij@linaro.org>

Header adds defines for the gpio number of each pad from the driver view.

The gpio block seems to have enough registers for 128 lines but what line
is mapped to a physical pin depends on the chip. The gpio block also seems
to contain some registers that are not related to gpio but needed somewhere
to go.

Because of the above the driver itself uses the index of a pin's offset in
an array of the possible offsets for a chip as the gpio number.
Signed-off-by: Daniel Palmer <daniel@0x0f.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20201129110803.2461700-2-daniel@0x0f.comSigned-off-by: Linus Walleij <linus.walleij@linaro.org>

Use a unique include guard for the Tegra186 GPIO DT bindings header to
avoid clashes with the DT bindings header for earlier chips.
Signed-off-by: Thierry Reding <treding@nvidia.com>
Link: https://lore.kernel.org/r/20201127140852.123192-2-thierry.reding@gmail.comSigned-off-by: Linus Walleij <linus.walleij@linaro.org>

The "Interacting With the Legacy GPIO Subsystem" of the documentation
was unclear at best, and even included a sentence that seems to say the
opposite of what it should say about the lifetime of the return value of
the conversion functions.

Try to clarify things a bit and hopefully make that section more
readable.
Reported-by: Andy Shevchenko <andy.shevchenko@gmail.com>
BugLink: https://stackoverflow.com/q/64455505/2511795Signed-off-by: Alexandre Courbot <gnurou@gmail.com>
Link: https://lore.kernel.org/r/20201122092548.61979-1-gnurou@gmail.comSigned-off-by: Linus Walleij <linus.walleij@linaro.org>

mxs is a devicetree-only platform and hence it does not make use
of the id_table mechanism.

Get rid of the .id_table as it is unused.
Signed-off-by: Fabio Estevam <festevam@gmail.com>
Link: https://lore.kernel.org/r/20201118191938.32693-1-festevam@gmail.comSigned-off-by: Linus Walleij <linus.walleij@linaro.org>

This assigns the .irq_set_affinity to the parent callback.
I assume the Tegra186 is an SMP system so this would be
beneficial.

I used the pattern making the hirerarchy tolerant for missing
parent as in Marc's earlier patch.
Suggested-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Cc: Thierry Reding <treding@nvidia.com>
Cc: Vidya Sagar <vidyas@nvidia.com>
Link: https://lore.kernel.org/r/20201117213351.249668-2-linus.walleij@linaro.org

This assigns the .irq_set_affinity to the parent callback.
I assume the sifive GPIO can be used in systems with
SMP.

I used the pattern making the hirerarchy tolerant for missing
parent as in Marc's earlier patches.
Suggested-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Cc: Yash Shah <yash.shah@sifive.com>
Cc: Wesley W. Terpstra <wesley@sifive.com>
Link: https://lore.kernel.org/r/20201117213351.249668-1-linus.walleij@linaro.org

If users select sysfs support they get the character device
as well so that end-users cannot complain that they
"only have sysfs on my system". They should have the
character device at all times.

If someone is in so dire need of stripping out the
character device while still enabling the sysfs ABI they
can very well patch the kernel.

Also only show this obsolete option to expert users.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20201110142724.14760-1-linus.walleij@linaro.org

Since 5.10-rc1 i.MX is a devicetree-only platform, so simplify the code
by removing the unused non-DT support.
Signed-off-by: Fabio Estevam <festevam@gmail.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Link: https://lore.kernel.org/r/20201117105917.27591-1-festevam@gmail.comSigned-off-by: Linus Walleij <linus.walleij@linaro.org>

Added entry for xilinx GPIO drivers.
Signed-off-by: Srinivas Neeli <srinivas.neeli@xilinx.com>
Acked-by: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com>
Acked-by: Michal Simek <michal.simek@xilinx.com>
Link: https://lore.kernel.org/r/1605201148-4508-10-git-send-email-srinivas.neeli@xilinx.comSigned-off-by: Linus Walleij <linus.walleij@linaro.org>

In two different instances the return value of "of_property_read_u32"
API was neither captured nor checked.
Fixed it by capturing the return value and then checking for any error.
Signed-off-by: Srinivas Neeli <srinivas.neeli@xilinx.com>
Acked-by: Michal Simek <michal.simek@xilinx.com>
Addresses-Coverity: "check_return"
Link: https://lore.kernel.org/r/1605201148-4508-9-git-send-email-srinivas.neeli@xilinx.comSigned-off-by: Linus Walleij <linus.walleij@linaro.org>

Added remove function support.
Signed-off-by: Srinivas Neeli <srinivas.neeli@xilinx.com>
Acked-by: Michal Simek <michal.simek@xilinx.com>
Link: https://lore.kernel.org/r/1605201148-4508-7-git-send-email-srinivas.neeli@xilinx.com
[dropped pm disable call]
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

Adds clock support to the Xilinx GPIO driver.
Signed-off-by: Srinivas Neeli <srinivas.neeli@xilinx.com>
Acked-by: Michal Simek <michal.simek@xilinx.com>
Link: https://lore.kernel.org/r/1605201148-4508-4-git-send-email-srinivas.neeli@xilinx.comSigned-off-by: Linus Walleij <linus.walleij@linaro.org>

Specify clock property in binding.
Signed-off-by: Srinivas Neeli <srinivas.neeli@xilinx.com>
Acked-by: Michal Simek <michal.simek@xilinx.com>
Link: https://lore.kernel.org/r/1605201148-4508-3-git-send-email-srinivas.neeli@xilinx.comSigned-off-by: Linus Walleij <linus.walleij@linaro.org>

Arrange header files in sorted order.
Signed-off-by: Srinivas Neeli <srinivas.neeli@xilinx.com>
Acked-by: Michal Simek <michal.simek@xilinx.com>
Link: https://lore.kernel.org/r/1605201148-4508-2-git-send-email-srinivas.neeli@xilinx.comSigned-off-by: Linus Walleij <linus.walleij@linaro.org>

Merge tag 'intel-gpio-v5.11-1' of gitolite.kernel.org:pub/scm/linux/kernel/git/andy/linux-gpio-intel into devel

intel-gpio for v5.11-1

* Refactor GPIO library to support bias and debounce ACPI settings

The following is an automated git shortlog grouped by driver:

gpiolib:
 -  acpi: Make Intel GPIO tree official for GPIO ACPI work
 -  acpi: Use BIT() macro to increase readability
 -  acpi: Convert pin_index to be u16
 -  acpi: Extract acpi_request_own_gpiod() helper
 -  acpi: Make acpi_gpio_to_gpiod_flags() usable for GpioInt()
 -  acpi: Set initial value for output pin based on bias and polarity
 -  acpi: Move acpi_gpio_to_gpiod_flags() upper in the code
 -  acpi: Move non-critical code outside of critical section
 -  acpi: Take into account debounce settings
 -  acpi: Use named item for enum gpiod_flags variable
 -  acpi: Respect bias settings for GpioInt() resource
 -  Introduce gpio_set_debounce_timeout() for internal use
 -  Extract gpio_set_config_with_argument_optional() helper
 -  move bias related code from gpio_set_config() to gpio_set_bias()
 -  Extract gpio_set_config_with_argument() for future use
 -  use proper API to pack pin configuration parameters
 -  add missed break statement
 -  Replace unsigned by unsigned int

Merge tag 'intel-pinctrl-v5.10-2' into HEAD:
 - Merge tag 'intel-pinctrl-v5.10-2' into HEAD

pinctrl:
 -  intel: Set default bias in case no particular value given
 -  intel: Fix 2 kOhm bias which is 833 Ohm

Linux 5.10-rc4

Make Intel GPIO tree official for GPIO ACPI work.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>

We may use BIT() macro to increase readability in
acpi_gpio_adr_space_handler().
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>

As specified by ACPI the pin index is 16-bit unsigned integer.
Define the variable, which holds it, accordingly.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>

It appears that we are using similar code excerpts for ACPI OpRegion
and event handling. Deduplicate those excerpts by extracting a new
acpi_request_own_gpiod() helper.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>

GpioInt() implies input configuration of the pin. Add this to
the acpi_gpio_to_gpiod_flags() and make usable for GpioInt().
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>

GpioIo() resources don't contain an initial value for the output pin.
Therefore instead of deducting its value solely based on bias field
we should deduce that value from the polarity and the bias fields.
Typical scenario is, when pin is defined in the table and its polarity,
specified in _DSD or via platform code, is defined as active low,
in the following call chain:

  -> acpi_populate_gpio_lookup()
     -> acpi_gpio_to_gpiod_flags()

it will return GPIOD_OUT_HIGH if bias is set no matter if polarity
is GPIO_ACTIVE_LOW, so it will return the current level instead of
the logical level.

Cc: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Vasile-Laurentiu Stanimir <vasile-laurentiu.stanimir@windriver.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>

Move acpi_gpio_to_gpiod_flags() upper in the code to allow further refactoring.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>

Mika noticed that some code is run under mutex when it doesn't require
the lock, like an error code assignment.

Move non-critical code outside of critical section.
Suggested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Cc: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>

We didn't take into account the debounce settings supplied by ACPI.
This change is targeting the mentioned gap.
Reported-by: Coiby Xu <coiby.xu@gmail.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>

Use named item instead of plain integer for enum gpiod_flags
to make it clear that even 0 has its own meaning.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>

In some cases the GpioInt() resource is coming with bias settings
which may affect system functioning. Respect bias settings for
GpioInt() resource by calling acpi_gpio_update_gpiod_*flags() API
in acpi_dev_gpio_irq_get().
Reported-by: Jamie McClymont <jamie@kwiius.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>

In some cases we would like to have debounce setter which doesn't fail
when a feature is not supported by a controller.

Cc: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>

This function is useful for internal use in the GPIO library.
There will be new user coming, prepare a helper for the new comer
and the existing ones.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>

Move bias related code from gpio_set_config() to gpio_set_bias().
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>

In the future we will need to have a separate function
that takes an arbitrary argument value.

Extract gpio_set_config_with_argument() for that purpose.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>

Instead of open coded macro use, call pinconf_to_config_packed().
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>

It's no difference in the functionality, but after the change the code
is less error prone to various checkers.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>