linux-toradex.git/drivers/gpio/gpiolib.h, branch v4.19-rc4

gpiolib: Mark gpio_suffixes array with __maybe_unused

2018-07-13T07:00:08+00:00

Since we put static variable to a header file it's copied to each module
that includes the header. But not all of them are actually used it.

Mark gpio_suffixes array with __maybe_unused to hide a compiler warning:

In file included from
drivers/gpio/gpiolib-legacy.c:6:0:
drivers/gpio/gpiolib.h:95:27: warning: ‘gpio_suffixes’ defined but not used [-Wunused-const-variable=]
 static const char * const gpio_suffixes[] = { "gpios", "gpio" };
                           ^~~~~~~~~~~~~
In file included from drivers/gpio/gpiolib-devprop.c:17:0:
drivers/gpio/gpiolib.h:95:27: warning: ‘gpio_suffixes’ defined but not used [-Wunused-const-variable=]
 static const char * const gpio_suffixes[] = { "gpios", "gpio" };
                           ^~~~~~~~~~~~~

Signed-off-by: Andy Shevchenko 
Signed-off-by: Linus Walleij

gpio: Remove VLA from gpiolib

2018-05-23T12:01:03+00:00

The new challenge is to remove VLAs from the kernel
(see https://lkml.org/lkml/2018/3/7/621) to eventually
turn on -Wvla.

Using a kmalloc array is the easy way to fix this but kmalloc is still
more expensive than stack allocation. Introduce a fast path with a
fixed size stack array to cover most chip with gpios below some fixed
amount. The slow path dynamically allocates an array to cover those
chips with a large number of gpios.

Reviewed-by: Geert Uytterhoeven 
Reviewed-by: Phil Reid 
Reviewed-and-tested-by: Lukas Wunner 
Signed-off-by: Lukas Wunner 
Signed-off-by: Laura Abbott 
Reviewed-by: Andy Shevchenko 
Signed-off-by: Linus Walleij

gpio: include consumer header in gpiolib.h

2018-02-22T14:30:31+00:00

We are forward-declaring enum gpiod_flags, but this is not referenced
by pointer, it is a real struct member, so we need to actually include
it to compile anything including the local gpiolib.h header.

Signed-off-by: Linus Walleij

Merge tag 'gpio-v4.16-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio

2018-01-31T20:25:27+00:00

Pull GPIO updates from Linus Walleij:
"The is the bulk of GPIO changes for the v4.16 kernel cycle. It is
pretty calm this time around I think. I even got time to get to things
like starting to clean up header includes.

Core changes:

- Disallow open drain and open source flags to be set simultaneously.
This doesn't make electrical sense, and would the hardware actually
respond to this setting, the result would be short circuit.

- ACPI GPIO has a new core infrastructure for handling quirks. The
quirks are there to deal with broken ACPI tables centrally instead
of pushing the work to individual drivers. In the world of BIOS
writers, the ACPI tables are perfect. Until they find a mistake in
it. When such a mistake is found, we can patch it with a quirk. It
should never happen, the problem is that it happens. So we
accomodate for it.

- Several documentation updates.

- Revert the patch setting up initial direction state from reading
the device. This was causing bad things for drivers that can't read
status on all its pins. It is only affecting debugfs information
quality.

- Label descriptors with the device name if no explicit label is
passed in.

- Pave the ground for transitioning SPI and regulators to use GPIO
descriptors by implementing some quirks in the device tree GPIO
parsing code.

New drivers:

- New driver for the Access PCIe IDIO 24 family.

Other:

- Major refactorings and improvements to the GPIO mockup driver used
for test and verification.

- Moved the AXP209 driver over to pin control since it gained a pin
control back-end. These patches will appear (with the same hashes)
in the pin control pull request as well.

- Convert the onewire GPIO driver w1-gpio to use descriptors. This is
merged here since the W1 maintainers send very few pull requests
and he ACKed it.

- Start to clean up driver headers using to just use
as appropriate"

* tag 'gpio-v4.16-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (103 commits)
gpio: Timestamp events in hardirq handler
gpio: Fix kernel stack leak to userspace
gpio: Fix a documentation spelling mistake
gpio: Documentation update
gpiolib: remove redundant initialization of pointer desc
gpio: of: Fix NPE from OF flags
gpio: stmpe: Delete an unnecessary variable initialisation in stmpe_gpio_probe()
gpio: stmpe: Move an assignment in stmpe_gpio_probe()
gpio: stmpe: Improve a size determination in stmpe_gpio_probe()
gpio: stmpe: Use seq_putc() in stmpe_dbg_show()
gpio: No NULL owner
gpio: stmpe: i2c transfer are forbiden in atomic context
gpio: davinci: Include proper header
gpio: da905x: Include proper header
gpio: cs5535: Include proper header
gpio: crystalcove: Include proper header
gpio: bt8xx: Include proper header
gpio: bcm-kona: Include proper header
gpio: arizona: Include proper header
gpio: amd8111: Include proper header
...

gpio: Export devm_gpiod_get_from_of_node() for consumers

2018-01-12T10:05:24+00:00

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: Linus Walleij

gpio: fix "gpio-line-names" property retrieval

2017-12-22T14:24:31+00:00

Following commit 9427ecbed46cc ("gpio: Rework of_gpiochip_set_names()
to use device property accessors"), "gpio-line-names" DT property is
not retrieved anymore when chip->parent is not set by the driver.
This is due to OF based property reads having been replaced by device
based property reads.

This patch fixes that by making use of
fwnode_property_read_string_array() instead of
device_property_read_string_array() and handing over either
of_fwnode_handle(chip->of_node) or dev_fwnode(chip->parent)
to that function.

Fixes: 9427ecbed46cc ("gpio: Rework of_gpiochip_set_names() to use device property accessors")
Cc: stable@vger.kernel.org
Signed-off-by: Christophe Leroy 
Acked-by: Mika Westerberg 
Signed-off-by: Linus Walleij

gpiolib: constify label in gpio_device

2017-12-20T08:01:50+00:00

This string is never modified. Make it const.

Signed-off-by: Bartosz Golaszewski 
Signed-off-by: Linus Walleij

gpio: gpiolib: Generalise state persistence beyond sleep

2017-12-02T21:42:34+00:00

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 
Reviewed-by: Charles Keepax 
Acked-by: Rob Herring 
Signed-off-by: Linus Walleij

gpiolib: acpi: Add quirks field to struct acpi_gpio_mapping

2017-11-30T09:53:51+00:00

Some broken ACPI tables might require quirks in the OS.
Introduce quirks field in struct acpi_gpio_mapping.

Propagate them to struct acpi_gpio_info for further use.

Signed-off-by: Andy Shevchenko 
Reviewed-by: Mika Westerberg 
Signed-off-by: Linus Walleij

gpiolib: acpi: Consolidate debug output in acpi_gpio_update_gpiod_flags()

2017-11-30T09:53:51+00:00

We have the duplicated debug strings printed whenever
acpi_gpio_update_gpiod_flags() fails. Instead of doing this by callers,
move the debug output inside function.

In one case convert almost useless pr_debug() to dev_dbg() where
actual consumer of GPIO resource is disclosed.

Signed-off-by: Andy Shevchenko 
Reviewed-by: Mika Westerberg 
Signed-off-by: Linus Walleij