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path: root/drivers/gpio/gpiolib.h
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2020-12-09Merge tag 'gpio-updates-for-v5.11' of ↵Linus Walleij
git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux into devel gpio updates for v5.11-rc1 - several refactoring patches of the core gpiolib code - add support for NXP PCAL9554B/C to gpio-pca953x - allow probing mockup devices from device tree - refactoring and improvements to gpio-rcar - improvements to locking in gpio-tegra - code shrink in gpiolib devres - get the irq offset from device tree in gpio-sifive - major refactoring of gpio-exar - convert gpio-mvebu pwm access to regmap - create a new submenu for virtual GPIO drivers - fix clang fall-through warnings treewide - minor driver refactoring and tweaks sprinkled all over
2020-12-05gpiolib: cdev: allow edge event timestamps to be configured as REALTIMEKent Gibson
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.com Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2020-11-16gpiolib: Introduce gpio_set_debounce_timeout() for internal useAndy Shevchenko
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>
2020-10-26gpiolib: Extract gpiod_not_found() helperAndy Shevchenko
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: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
2020-09-30gpiolib: cdev: support setting debounceKent Gibson
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>
2020-09-30gpiolib: cdev: support edge detection for uAPI v2Kent Gibson
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>
2020-07-12gpiolib: cdev: use blocking notifier call chain instead of atomicKent Gibson
Replace usage of atomic_notifier_call_chain with blocking_notifier_call_chain as the notifier function, lineinfo_changed_notify, calls gpio_desc_to_lineinfo, which calls pinctrl_gpio_can_use_line, which can sleep. The chain isn't being called from an atomic context so the the blocking notifier is a suitable substitute. Signed-off-by: Kent Gibson <warthog618@gmail.com> Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
2020-07-12gpiolib: move gpiolib-sysfs function declarations into their own headerKent Gibson
Move gpiolib-sysfs function declarations into their own header. These functions are in gpiolib-sysfs.c, and are only required by gpiolib.c, and so should be in a module header, not gpiolib.h. This brings gpiolib-sysfs into line with gpiolib-cdev, and is another step towards removing the sysfs inferface. Signed-off-by: Kent Gibson <warthog618@gmail.com> Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
2020-04-28gpiolib: Rename "chip" variables to "gc" in core header fileGeert Uytterhoeven
Consistently use "gc" for "struct gpio *" variables. This follows the spirit of commit a0b66a73785ccc8f ("gpio: Rename variable in core APIs"). Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Link: https://lore.kernel.org/r/20200424141517.11582-1-geert+renesas@glider.be Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2020-02-21gpio: of: Add DT overlay support for GPIO hogsGeert Uytterhoeven
As GPIO hogs are configured at GPIO controller initialization time, adding/removing GPIO hogs in DT overlays does not work. Add support for GPIO hogs described in DT overlays by registering an OF reconfiguration notifier, to handle the addition and removal of GPIO hog subnodes to/from a GPIO controller device node. Note that when a GPIO hog device node is being removed, its "gpios" properties is no longer available, so we have to keep track of which node a hog belongs to, which is done by adding a pointer to the hog's device node to struct gpio_desc. Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Link: https://lore.kernel.org/r/20200220130149.26283-3-geert+renesas@glider.be Reviewed-by: Frank Rowand <frank.rowand@sony.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2020-02-12gpiolib: add new ioctl() for monitoring changes in line infoBartosz Golaszewski
Currently there is no way for user-space to be informed about changes in status of GPIO lines e.g. when someone else requests the line or its config changes. We can only periodically re-read the line-info. This is fine for simple one-off user-space tools, but any daemon that provides a centralized access to GPIO chips would benefit hugely from an event driven line info synchronization. This patch adds a new ioctl() that allows user-space processes to reuse the file descriptor associated with the character device for watching any changes in line properties. Every such event contains the updated line information. Currently the events are generated on three types of status changes: when a line is requested, when it's released and when its config is changed. The first two are self-explanatory. For the third one: this will only happen when another user-space process calls the new SET_CONFIG ioctl() as any changes that can happen from within the kernel (i.e. set_transitory() or set_debounce()) are of no interest to user-space. Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com> Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
2020-01-07Merge tag 'gpio-updates-for-v5.6-part1' of ↵Linus Walleij
git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux into devel gpio updates for v5.6 - improvements in the gpio-pca953x driver - use platform_irq_count() in gpio-mvebu and gpio-bcm-kona - remove unneeded MODULE_VERSION() usage in the gpio directory - irq-related improvements in gpio-tegra driver - several improvements for the core subsystem code: fix confusing indentation, fix int type casting, unduplicate code in several places
2020-01-07gpiolib: convert the type of hwnum to unsigned int in gpiochip_get_desc()Bartosz Golaszewski
gpiochip_get_desc() takes a u16 hwnum, but it turns out most users don't respect that and usually pass an unsigned int. Since implicit casting to a smaller type is dangerous - let's change the type of hwnum to unsigned int in gpiochip_get_desc() and in gpiochip_request_own_desc() where the size of hwnum is not respected either and who's a user of the former. This is safe as we then check the hwnum against the number of lines before proceeding in gpiochip_get_desc(). Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
2019-12-12gpiolib: Add GPIOCHIP_NAME definitionGeert Uytterhoeven
The string literal "gpiochip" is used in several places. Add a definition for it, and use it everywhere, to make sure everything stays in sync. Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Link: https://lore.kernel.org/r/20191127084253.16356-2-geert+renesas@glider.be Reviewed-by: Ulrich Hecht <uli+renesas@fpond.eu> Reviewed-by: Eugeniu Rosca <erosca@de.adit-jv.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2019-11-12gpiolib: add support for disabling line biasKent Gibson
Allow pull up/down bias to be disabled, allowing the line to float or to be biased only by external circuitry. Use case is for where the bias has been applied previously, either by default or by the user, but that setting may conflict with the current use of the line. Signed-off-by: Kent Gibson <warthog618@gmail.com> Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
2019-07-31gpiolib: acpi: Split ACPI stuff to gpiolib-acpi.hAndy Shevchenko
This is a follow up to the commit f626d6dfb709 ("gpio: of: Break out OF-only code") which broke down OF parts of GPIO library. Here we do the similar to ACPI. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20190730104337.21235-2-andriy.shevchenko@linux.intel.com Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2019-07-28gpio: of: Break out OF-only codeLinus Walleij
The core gpiolib should not contain any OF/device tree-only code. Try to break out the main part of it and push it down into the optional gpiolib-of.c part of the library. Create a local gpiolib-of.h header and move stuff around a bit to get a clean cut. Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Link: https://lore.kernel.org/r/20190717071001.3858-1-linus.walleij@linaro.org
2019-07-06gpiolib: Use spinlock_t instead of struct spinlockSebastian Andrzej Siewior
For spinlocks the type spinlock_t should be used instead of "struct spinlock". Use spinlock_t for spinlock's definition. Cc: linux-gpio@vger.kernel.org Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Link: https://lore.kernel.org/r/20190704153803.12739-8-bigeasy@linutronix.de Reviewed-by: Bartosz Golaszewski <bgolaszewski@baylibre.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2019-05-11Merge tag 'gpio-v5.2-1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio Pull gpio updates from Linus Walleij: "This is the bulk of the GPIO changes for the v5.2 kernel cycle. A bit later than usual because I was ironing out my own mistakes. I'm holding some stuff back for the next kernel as a result, and this should be a healthy and well tested batch. Core changes: - The gpiolib MMIO driver has been enhanced to handle two direction registers, i.e. one register to set lines as input and one register to set lines as output. It turns out some silicon engineer thinks the ability to configure a line as input and output at the same time makes sense, this can be debated but includes a lot of analog electronics reasoning, and the registers are there and need to be handled consistently. Unsurprisingly, we enforce the lines to be either inputs or outputs in such schemes. - Send in the proper argument value to .set_config() dispatched to the pin control subsystem. Nobody used it before, now someone does, so fix it to work as expected. - The ACPI gpiolib portions can now handle pin bias setting (pull up or pull down). This has been in the ACPI spec for years and we finally have it properly integrated with Linux GPIOs. It was based on an observation from Andy Schevchenko that Thomas Petazzoni's changes to the core for biasing the PCA950x GPIO expander actually happen to fit hand-in-glove with what the ACPI core needed. Such nice synergies happen sometimes. New drivers: - A new driver for the Mellanox BlueField GPIO controller. This is using 64bit MMIO registers and can configure lines as inputs and outputs at the same time and after improving the MMIO library we handle it just fine. Interesting. - A new IXP4xx proper gpiochip driver with hierarchical interrupts should be coming in from the ARM SoC tree as well. Driver enhancements: - The PCA053x driver handles the CAT9554 GPIO expander. - The PCA053x driver handles the NXP PCAL6416 GPIO expander. - Wake-up support on PCA053x GPIO lines. - OMAP now does a nice asynchronous IRQ handling on wake-ups by letting everything wake up on edges, and this makes runtime PM work as expected too. Misc: - Several cleanups such as devres fixes. - Get rid of some languager comstructs that cause problems when compiling with LLVMs clang. - Documentation review and update" * tag 'gpio-v5.2-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (85 commits) gpio: Update documentation docs: gpio: convert docs to ReST and rename to *.rst gpio: sch: Remove write-only core_base gpio: pxa: Make two symbols static gpiolib: acpi: Respect pin bias setting gpiolib: acpi: Add acpi_gpio_update_gpiod_lookup_flags() helper gpiolib: acpi: Set pin value, based on bias, more accurately gpiolib: acpi: Change type of dflags gpiolib: Introduce GPIO_LOOKUP_FLAGS_DEFAULT gpiolib: Make use of enum gpio_lookup_flags consistent gpiolib: Indent entry values of enum gpio_lookup_flags gpio: pca953x: add support for pca6416 dt-bindings: gpio: pca953x: document the nxp,pca6416 gpio: pca953x: add pcal6416 to the of_device_id table gpio: gpio-omap: Remove conditional pm_runtime handling for GPIO interrupts gpio: gpio-omap: configure edge detection for level IRQs for idle wakeup tracing: stop making gpio tracing configurable gpio: pca953x: Configure wake-up path when wake-up is enabled gpio: of: Optimize quirk checks gpio: mmio: Drop bgpio_dir_inverted ...
2019-04-23gpiolib: acpi: Respect pin bias settingAndy Shevchenko
For now, we don't take into account the pin bias settings supplied by ACPI. This change is targeting the mentioned gap. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Hans de Goede <hdegoede@redhat.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2019-04-23gpiolib: acpi: Add acpi_gpio_update_gpiod_lookup_flags() helperAndy Shevchenko
This helper consolidates all settings of GPIO descriptor lookup flags and quirks in the future if any. No functional change intended. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Hans de Goede <hdegoede@redhat.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2019-04-23gpiolib: Make use of enum gpio_lookup_flags consistentAndy Shevchenko
The library uses enum gpio_lookup_flags to define the possible characteristics of GPIO pin. Since enumerator listed only individual bits the common use of it is in a form of a bitmask of gpio_lookup_flags GPIO_* values. The more correct type for this is unsigned long. Due to above convert all users to use unsigned long instead of enum gpio_lookup_flags except enumerator definition. While here, make field and parameter descriptions consistent as well. Suggested-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2019-03-24gpiolib: export devprop_gpiochip_set_names()Jan Kundrát
This function is needed in mcp23s08. That driver is a special snowflake because it supports several hardware chips as a single "GPIO chip" under Linux. Signed-off-by: Jan Kundrát <jan.kundrat@cesnet.cz> Cc: Linus Walleij <linus.walleij@linaro.org> Cc: Phil Reid <preid@electromag.com.au> Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2019-02-13gpio: add core support for pull-up/pull-down configurationThomas Petazzoni
This commit adds support for configuring the pull-up and pull-down resistors available in some GPIO controllers. While configuring pull-up/pull-down is already possible through the pinctrl subsystem, some GPIO controllers, especially simple ones such as GPIO expanders on I2C, don't have any pinmuxing capability and therefore do not use the pinctrl subsystem. This commit implements the GPIO_PULL_UP and GPIO_PULL_DOWN flags, which can be used from the Device Tree, to enable a pull-up or pull-down resistor on a given GPIO. The flag is simply propagated all the way to the core GPIO subsystem, where it is used to call the gpio_chip ->set_config callback with the appropriate existing PIN_CONFIG_BIAS_* values. Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-12-11gpio: Export gpiod_get_from_of_node()Linus Walleij
This function already exist inside gpiolib, we were just reluctant to make it available to the kernel at large as the devm_* seemed to be enough for anyone. However we found out that regulators need to do their own lifecycle/refcounting on GPIO descriptors and explicitly call gpiod_put() when done with a descriptor, so export this function so we can hand the refcounting over to the regulator core for these descriptors after retrieveal. Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Reviewed-by: Marek Szyprowski <m.szyprowski@samsung.com> Tested-by: Marek Szyprowski <m.szyprowski@samsung.com> Reviewed-by: Charles Keepax <ckeepax@opensource.cirrus.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2018-10-01gpio: Restore indentation of continued linesGeert Uytterhoeven
Fixes: 3027743f83f867d8 ("gpio: Remove VLA from gpiolib") Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-09-25gpio: Use SPDX header for core libraryLinus Walleij
Use the SPDX headers and cut down on boilerplate to indicate the license in the core gpiolib implementation. Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-09-20Merge branch 'ib-array-bitmaps' into develLinus Walleij
2018-09-13gpiolib: Pass array info to get/set array functionsJanusz Krzysztofik
In order to make use of array info obtained from gpiod_get_array() and speed up processing of arrays matching single GPIO chip layout, that information must be passed to get/set array functions. Extend the functions' API with that additional parameter and update all users. Pass NULL if a user builds an array itself from single GPIOs. Cc: Jonathan Corbet <corbet@lwn.net> Cc: Miguel Ojeda Sandonis <miguel.ojeda.sandonis@gmail.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Sebastien Bourdelin <sebastien.bourdelin@savoirfairelinux.com> Cc: Lukas Wunner <lukas@wunner.de> Cc: Peter Korsgaard <peter.korsgaard@barco.com> Cc: Peter Rosin <peda@axentia.se> Cc: Andrew Lunn <andrew@lunn.ch> Cc: Florian Fainelli <f.fainelli@gmail.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Rojhalat Ibrahim <imr@rtschenk.de> Cc: Dominik Brodowski <linux@dominikbrodowski.net> Cc: Russell King <rmk+kernel@armlinux.org.uk> Cc: Kishon Vijay Abraham I <kishon@ti.com> Cc: Tony Lindgren <tony@atomide.com> Cc: Lars-Peter Clausen <lars@metafoo.de> Cc: Michael Hennerich <Michael.Hennerich@analog.com> Cc: Jonathan Cameron <jic23@kernel.org> Cc: Hartmut Knaack <knaack.h@gmx.de> Cc: Peter Meerwald-Stadler <pmeerw@pmeerw.net> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jiri Slaby <jslaby@suse.com> Cc: Yegor Yefremov <yegorslists@googlemail.com> Cc: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Janusz Krzysztofik <jmkrzyszt@gmail.com> Acked-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-09-13gpiolib: Identify arrays matching GPIO hardwareJanusz Krzysztofik
Certain GPIO array lookup results may map directly to GPIO pins of a single GPIO chip in hardware order. If that condition is recognized and handled efficiently, significant performance gain of get/set array functions may be possible. While processing a request for an array of GPIO descriptors, identify those which represent corresponding pins of a single GPIO chip. Skip over pins which require open source or open drain special processing. Moreover, identify pins which require inversion. Pass a pointer to that information with the array to the caller so it can benefit from enhanced performance as soon as get/set array functions can accept and make efficient use of it. Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Janusz Krzysztofik <jmkrzyszt@gmail.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-09-13gpiolib: Pass bitmaps, not integer arrays, to get/set arrayJanusz Krzysztofik
Most users of get/set array functions iterate consecutive bits of data, usually a single integer, while processing array of results obtained from, or building an array of values to be passed to those functions. Save time wasted on those iterations by changing the functions' API to accept bitmaps. All current users are updated as well. More benefits from the change are expected as soon as planned support for accepting/passing those bitmaps directly from/to respective GPIO chip callbacks if applicable is implemented. Cc: Jonathan Corbet <corbet@lwn.net> Cc: Miguel Ojeda Sandonis <miguel.ojeda.sandonis@gmail.com> Cc: Sebastien Bourdelin <sebastien.bourdelin@savoirfairelinux.com> Cc: Lukas Wunner <lukas@wunner.de> Cc: Peter Korsgaard <peter.korsgaard@barco.com> Cc: Peter Rosin <peda@axentia.se> Cc: Andrew Lunn <andrew@lunn.ch> Cc: Florian Fainelli <f.fainelli@gmail.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Rojhalat Ibrahim <imr@rtschenk.de> Cc: Dominik Brodowski <linux@dominikbrodowski.net> Cc: Russell King <rmk+kernel@armlinux.org.uk> Cc: Kishon Vijay Abraham I <kishon@ti.com> Cc: Tony Lindgren <tony@atomide.com> Cc: Lars-Peter Clausen <lars@metafoo.de> Cc: Michael Hennerich <Michael.Hennerich@analog.com> Cc: Jonathan Cameron <jic23@kernel.org> Cc: Hartmut Knaack <knaack.h@gmx.de> Cc: Peter Meerwald-Stadler <pmeerw@pmeerw.net> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jiri Slaby <jslaby@suse.com> Cc: Yegor Yefremov <yegorslists@googlemail.com> Cc: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Janusz Krzysztofik <jmkrzyszt@gmail.com> Acked-by: Ulf Hansson <ulf.hansson@linaro.org> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Tested-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-09-10gpiolib: add flag to indicate if the irq is disabledHans Verkuil
GPIO drivers call gpiochip_(un)lock_as_irq whenever they want to use a gpio as an interrupt. This is done when the irq is requested and it marks the gpio as in use by an interrupt. This is problematic for cases where a gpio pin is used as an interrupt pin, then, after the irq is disabled, is used as a regular gpio pin. Currently it is not possible to do this other than by first freeing the interrupt so gpiochip_unlock_as_irq is called, since an attempt to switch the gpio direction for output will fail since gpiolib believes that the gpio is in use for an interrupt and it does not know that it the irq is actually disabled. There are currently two drivers that would like to be able to do this: the tda998x_drv.c driver where a regular gpio pin needs to be temporarily reconfigured as an interrupt pin during CEC calibration, and the cec-gpio driver where you want to configure the gpio pin as an interrupt while waiting for traffic over the CEC bus, or as a regular pin when receiving or transmitting a CEC message. The solution is to add a new flag that is set when the irq is enabled, and have gpiod_direction_output check for that flag. We also add functions that drivers that do not use GPIOLIB_IRQCHIP can call when they enable/disable the irq. Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-07-13gpiolib: Mark gpio_suffixes array with __maybe_unusedAndy Shevchenko
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 <andriy.shevchenko@linux.intel.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-05-23gpio: Remove VLA from gpiolibLaura Abbott
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 <geert+renesas@glider.be> Reviewed-by: Phil Reid <preid@electromag.com.au> Reviewed-and-tested-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Laura Abbott <labbott@redhat.com> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-02-22gpio: include consumer header in gpiolib.hLinus Walleij
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 <linus.walleij@linaro.org>
2018-01-31Merge tag 'gpio-v4.16-1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio 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 <linux/gpio.h> to just use <linux/gpio/driver.h> 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 ...
2018-01-12gpio: Export devm_gpiod_get_from_of_node() for consumersLinus Walleij
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 <linus.walleij@linaro.org>
2017-12-22gpio: fix "gpio-line-names" property retrievalChristophe Leroy
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 <christophe.leroy@c-s.fr> Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-12-20gpiolib: constify label in gpio_deviceBartosz Golaszewski
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>
2017-12-02gpio: gpiolib: Generalise state persistence beyond sleepAndrew Jeffery
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>
2017-11-30gpiolib: acpi: Add quirks field to struct acpi_gpio_mappingAndy Shevchenko
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 <andriy.shevchenko@linux.intel.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-11-30gpiolib: acpi: Consolidate debug output in acpi_gpio_update_gpiod_flags()Andy Shevchenko
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 <andriy.shevchenko@linux.intel.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-11-30gpiolib: acpi: Move adev member to struct acpi_gpio_infoAndy Shevchenko
The further improvements are based on this change since struct acpi_gpio_lookup is not available in some cases. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-10-20gpio: Fix loose spellingAndrew Jeffery
Literally. I expect "lose" was meant here, rather than "loose", though you could feasibly use a somewhat uncommon definition of "loose" to mean what would be meant by "lose": "Loose the hounds" for instance, as in "Release the hounds". Substituting in "value" for "hounds" gives "release the value", and makes some sense, but futher substituting back to loose gives "loose the value" which overall just seems a bit anachronistic. Instead, use modern, pragmatic English and save a character. Cc: Russell Currey <ruscur@russell.cc> Signed-off-by: Andrew Jeffery <andrew@aj.id.au> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-10-19gpio: Introduce ->get_multiple callbackLukas Wunner
SPI-attached GPIO controllers typically read out all inputs in one go. If callers desire the values of multipe inputs, ideally a single readout should take place to return the desired values. However the current driver API only offers a ->get callback but no ->get_multiple (unlike ->set_multiple, which is present). Thus, to read multiple inputs, a full readout needs to be performed for every single value (barring driver-internal caching), which is inefficient. In fact, the lack of a ->get_multiple callback has been bemoaned repeatedly by the gpio subsystem maintainer: http://www.spinics.net/lists/linux-gpio/msg10571.html http://www.spinics.net/lists/devicetree/msg121734.html Introduce the missing callback. Add corresponding consumer functions such as gpiod_get_array_value(). Amend linehandle_ioctl() to take advantage of the newly added infrastructure. Update the documentation. Cc: Rojhalat Ibrahim <imr@rtschenk.de> Signed-off-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-08-14gpio: replace __maybe_unused in gpiolib.h with static inlineMasahiro Yamada
In header files, static inline is more commonly used. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-05-29gpio: acpi: Override GPIO initialization flagsAndy Shevchenko
This allows ACPI GPIO code to modify flags based on ACPI GpioIo() / GpioInt() resources. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Tested-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-05-29gpiolib: Export gpiod_configure_flags() to internal usersAndy Shevchenko
This is preparatory patch for enabling GPIO ACPI to configure a pin accordingly. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Tested-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-05-29gpio: Add new flags to control sleep status of GPIOsCharles Keepax
Add new flags to allow users to specify that they are not concerned with the status of GPIOs whilst in a sleep/low power state. Signed-off-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com> Acked-by: Rob Herring <robh@kernel.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-01-11gpiolib: Update documentation of struct acpi_gpio_infoAndy Shevchenko
It seems the code had been changed, but description left untouched. Update description of the struct acpi_gpio_info and relative comments accordingly. Fixes: commit 52044723cd27 ("ACPI / gpio: Add irq_type when a GPIO is used as an interrupt") Cc: Christophe RICARD <christophe.ricard@gmail.com> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>