u_int32_t is a non-standard version of uint32_t, that was apparently
introduced by BSD. Use uint32_t from stdint.h instead.

Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

A 'perf record' on an app continuously writing in the 'value'
attribute show that most of the time is spent in kstrtol()

--17.99%--value_store
          |
          |--10.17%--kstrtoint
          |          |
          |          |--8.82%--kstrtoll
          |
          |--2.50%--gpiod_set_value_cansleep
          |
          |--1.82%--u16_gpio_set
          |
          |--1.46%--value_store

The normal case is to write 0 or 1 in the attribute, therefore
this patch avoids the call to kstrtol() in the most common cases

Then 'perf record' shows

--7.21%--value_store
          |
          |--2.69%--u16_gpio_set
          |
          |--1.47%--value_store
          |
          |--1.08%--gpiod_set_value_cansleep
          |
          |--0.60%--mutex_lock
          |
           --0.58%--mutex_unlock

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

A bench with 'perf record' shows that most of time spent in value_show()
is spent in sprintf()

--42.41%--sysfs_kf_read
          |
          |--39.73%--dev_attr_show
          |          |
          |          |--38.23%--value_show
          |          |          |
          |          |          |--29.22%--sprintf
          |          |          |
          |          |          |--2.94%--gpiod_get_value_cansleep
          |          |          |

value_show() only returns "0\n" or "1\n", therefore the use of
sprintf() can be avoided

With this patch we get the following result with 'perf record'

--13.89%--sysfs_kf_read
          |
          |--10.72%--dev_attr_show
          |          |
          |          |--9.44%--value_show
          |          |          |
          |          |          |--4.61%--gpiod_get_value_cansleep

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

'value' attribute is supposed to only return 0 or 1 according to
the documentation.
With today's implementation, if gpiod_get_value_cansleep() fails
the printed 'value' is a negative value.

This patch ensures that an error is returned on read instead.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

The GPIO 'value' attribute is time critical. A small bench with
'perf record' on the app below shows that 80% of the time spent in
sysfs_kf_seq_show() is spent in memset() for zeroising the buffer.

|--67.48%--sysfs_kf_seq_show
|          |
|          |--54.40%--memset
|          |
|          |--11.49%--dev_attr_show
|          |          |
|          |          |--10.06%--value_show
|          |          |          |
|          |          |          |--4.75%--sprintf
|          |          |          |          |

This patch changes the attribute type to prealloc, eliminating the
need to zeroise the buffer at each read. 'perf record' gives the
following result.

|--42.41%--sysfs_kf_read
|          |
|          |--39.73%--dev_attr_show
|          |          |
|          |          |--38.23%--value_show
|          |          |          |
|          |          |          |--29.22%--sprintf
|          |          |          |          |

Test done with the following small app:

int main(int argc, char **argv)
{
	int fd = open(argv[1], O_RDONLY);

	for (;;) {
		int buf[512];

		read(fd, buf, 512);
		lseek(fd, 0, SEEK_SET);
	}
	exit(0);
}

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

Users often pass a pointer to a static string to gpiochip_add_data()
family of functions. Avoid unnecessary memory allocations with the
provided helper routine.

While at it: use a ternary operator instead of an if else for brevity.

Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

This string is never modified. Make it const.

Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

The return value of platform_device_register_resndata() on error is
an error code converted to pointer with ERR_PTR(), not NULL.

Check the return value correctly.

Fixes: 8a39f597

 ("gpio: mockup: rework device probing")
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

The w1 master driver includes a complete open drain emulation
reimplementation among other things.

This converts the driver and all board files using it to use
GPIO descriptors associated with the device to look up the
GPIO wire, as well ass the optional pull-up GPIO line.

When probed from the device tree, the driver will just pick
descriptors and use them right off. For the two board files
in the kernel, we add descriptor lookups so we do not need
to keep any old platform data handling around for the GPIO
lines.

As the platform data is also a state container for this driver,
we augment it to contain the GPIO descriptors.

w1_gpio_write_bit_dir() and w1_gpio_write_bit_val() are gone
since this pair was a reimplementation of open drain emulation
which is now handled by gpiolib.

The special "linux,open-drain" flag is a bit of mishap here:
it has the same semantic as the same flags in I2C: it means
that something in the platform is setting up the line as
open drain behind our back. We handle this the same way as
in I2C.

To drive the pull-up, we need to bypass open drain emulation
in gpiolib for the line, and this is done by driving it high
using gpiod_set_raw_value() which has been augmented to have
the semantic of overriding the open drain emulation.

We also augment the documentation to reflect the way to pass
GPIO descriptors from the machine.

Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

The AXP813 has only two GPIOs. GPIO0 can either be used as a GPIO, an
LDO regulator or an ADC. GPIO1 can be used either as a GPIO or an LDO
regulator.

Moreover, the status bit of the GPIOs when in input mode is not offset
by 4 unlike the AXP209.

Signed-off-by: Quentin Schulz <quentin.schulz@free-electrons.com>
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

To prepare for patches that will add support for a new PMIC that has a
different GPIO adc muxing value, add an adc_mux within axp20x_pctl
structure and use it.

Signed-off-by: Quentin Schulz <quentin.schulz@free-electrons.com>
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

To prepare for patches that will add support for a new PMIC that has a
different GPIO input status register, add a gpio_status_offset within
axp20x_pctl structure and use it.

Signed-off-by: Quentin Schulz <quentin.schulz@free-electrons.com>
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

This driver used to do only GPIO features of the GPIOs in X-Powers
AXP20X. Now that we have migrated everything to the pinctrl subsystem
and added pinctrl features, rename everything related to pinctrl from
gpio to pctl to ease the understanding of differences between GPIO
and pinctrl features.

Signed-off-by: Quentin Schulz <quentin.schulz@free-electrons.com>
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

The X-Powers AXP209 has 3 GPIOs. GPIO0/1 can each act either as a GPIO,
an ADC or a LDO regulator. GPIO2 can only act as a GPIO.

This adds the pinctrl features to the driver so GPIO0/1 can be used as
ADC or LDO regulator.

Signed-off-by: Quentin Schulz <quentin.schulz@free-electrons.com>
Acked-by: Rob Herring <robh@kernel.org>
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

The X-Powers AXP209 has 3 GPIOs. GPIO0/1 can each act either as a GPIO,
an ADC or a LDO regulator. GPIO2 can only act as a GPIO.

This adds the pinctrl features to the driver so GPIO0/1 can be used as
ADC or LDO regulator.

Signed-off-by: Quentin Schulz <quentin.schulz@free-electrons.com>
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

To prepare the driver for the upcoming pinctrl features, move the GPIO
driver AXP209 from GPIO to pinctrl subsystem.

Signed-off-by: Quentin Schulz <quentin.schulz@free-electrons.com>
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

Checkpatch complains with the following message:
WARNING: Prefer 'unsigned int' to bare use of 'unsigned'

Let's make it happy by switching over to unsigned int.

Signed-off-by: Quentin Schulz <quentin.schulz@free-electrons.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

The platform_get_irq() function returns negative if an error occurs.
zero or positive number on success. platform_get_irq() error checking
for zero is not correct.

Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

Use the new pinconf parameter for state persistence to expose the
associated capability of the Aspeed GPIO controller.

Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Reviewed-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

General support for state persistence is added to gpiolib with the
introduction of a new pinconf parameter to propagate the request to
hardware. The existing persistence support for sleep is adapted to
include hardware support if the GPIO driver provides it. Persistence
continues to be enabled by default; in-kernel consumers can opt out, but
userspace (currently) does not have a choice.

The *_SLEEP_MAY_LOSE_VALUE and *_SLEEP_MAINTAIN_VALUE symbols are
renamed, dropping the SLEEP prefix to reflect that the concept is no
longer sleep-specific.  I feel that renaming to just *_MAY_LOSE_VALUE
could initially be misinterpreted, so I've further changed the symbols
to *_TRANSITORY and *_PERSISTENT to address this.

The sysfs interface is modified only to keep consistency with the
chardev interface in enforcing persistence for userspace exports.

Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Reviewed-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

Don't populate the read-only arrays edge_det_values, rise_values and
fall_values on the stack but instead make them static and constify them.
Makes the object code smaller by over 240 bytes:

Before:
   text	   data	    bss	    dec	    hex	filename
   9525	   2520	    192	  12237	   2fcd	drivers/gpio/gpio-stmpe.o

After:
   text	   data	    bss	    dec	    hex	filename
   9025	   2776	    192	  11993	   2ed9	drivers/gpio/gpio-stmpe.o

(gcc version 7.2.0 x86_64)

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

It had twice-encoded Unicode.

Signed-off-by: Adam Borowski <kilobyte@angband.pl>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

The user space libgpiod project is now tightly coupled with the
gpio-mockup module, so let me know when any changes to it are being
proposed.

Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

In order to avoid repeating the calculations on every access - add
helpers for gpio base and ngpio components of the ranges array.

Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

This variable holds the number of mockup GPIO ranges so rename it
accordingly.

Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

As discussed with Marc Zyngier: irq_sim_init() and its devres variant
should return the base of the allocated interrupt range on success
rather than 0. This will be modified later - first, change the way
users handle the return value of these routines.

Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

Implement the set_multiple() callback and register it with the gpiolib
framework. This is only meant to also test the internal kernel API.

Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

Minor readability tweak: prefer breaking the lines in a way where the
second part is longer than the first.

Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

Improve the module params sanitization: bail out from init if the user
tries to pass a non-positive number of GPIO lines for any mockup chip.

Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

The debugfs routines returning pointers can return NULL or error codes
embedded with ERR_PTR(). Check the return values with IS_ERR_OR_NULL().

While we're at it: make the error message more specific so it's not
confused with the one emitted when the top-level gpio-mockup debugfs
directory creation fails.

Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

Keep GPIO chip callbacks, event trigger callbacks and mockup chip
setup code visibly separated. We're mostly good - just need to move
the line naming routine below.

Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

GPIO values are universally represented as integers. Change the type
of the variable storing the current line value to int for consistency.

Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

Currently each chip has a dedicated directory in debugfs for event
triggers. We use the chip's label for the directory name, but the user
can't really associate these directories with chip names without
parsing the relevant sysfs entries.

Use chip names for directory names. For backward compatibility: create
links pointing to the actual directories named using the chip labels.

Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

Move the last bits of code dealing with module parameters to the init
function. Add a new variable to platform data, which indicates to the
probe function if it should name the GPIO lines. If we ever want to
make the line naming more fine-grained (e.g. per chip switch) it will
be easier this way.

Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

Now that the probe() function only does what is should, there's no
need to split the chip adding logic into a separate routine. Merge
gpio_mockup_add() into gpio_mockup_probe().

Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

Minor coding style fix.

Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

Visually shrink the pr_err() calls by encapsulating adding the module
name prefix to the message in a macro.

Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

We currently create a single platform device in init and then parse
the configuration passed to us via module parameters in probe() before
creating GPIO chips and registering them with the gpiolib framework.

The relation between platform devices and mockup chips should be 1:1.

Create a separate platform device for each mockup chip using convenient
helpers (platform_device_register_resndata()). Pass a platform data
structure to probe() in which the configuration (GPIO base, number of
lines, chip index) extracted from the module params is stored. Make
probe() create a single mockup chip for every platform device.

This approach has several advantages:
- we only parse the module parameters in init() and can bail out before
  attaching any device if the input is invalid (currently we would
  have to examine kernel logs),
- we'll get notified by the device framework about errors in probe()
  for specific chips,
- probe() gets simplified and only does what it's supposed to.

Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

The number of supported mockup chips is limited. Check this limit when
parsing the module parameters.

Also: make sure that each chip is described with a <base - ngpio> pair.

Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>