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2018-03-23Documentation: gpio: Move drivers-on-gpio.txt to driver-apiJonathan Neuschäfer3-102/+2
Move gpio/drivers-on-gpio.txt to driver-api/gpio/drivers-on-gpio.rst and make sure it builds cleanly as ReST. Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-03-23Documentation: gpio: Move GPIO mapping documentation to driver-apiJonathan Neuschäfer2-178/+0
Move gpio/board.txt to driver-api/gpio/board.rst and make sure it builds cleanly as ReST. Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-03-23Documentation: gpio: Move gpiod_* consumer documentation to driver-apiJonathan Neuschäfer2-440/+0
Move gpio/consumer.txt to driver-api/gpio/consumer.rst and make sure it builds cleanly as ReST. Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-03-23Documentation: gpio: Move legacy documentation to driver-apiJonathan Neuschäfer2-760/+0
Move gpio/gpio-legacy.txt to driver-api/gpio/legacy.rst and make sure it builds cleanly as ReST. Also move the legacy API reference from index.rst to legacy.rst. Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-03-23Documentation: gpio: Move driver documentation to driver-apiJonathan Neuschäfer2-429/+0
Move gpio/driver.txt to driver-api/gpio/driver.rst and make sure it builds cleanly as ReST. Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-03-23Documentation: gpio: Move introduction to driver-apiJonathan Neuschäfer2-121/+0
Move gpio/intro.txt to driver-api/gpio/intro.rst and make sure it builds cleanly as ReST. Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-02-01Merge branch 'for-linus' of ↵Linus Torvalds1-5/+0
git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input Pull input layer updates from Dmitry Torokhov: - evdev interface has been adjusted to extend the life of timestamps on 32 bit systems to the year of 2108 - Synaptics RMI4 driver's PS/2 guest handling ha beed updated to improve chances of detecting trackpoints on the pass-through port - mms114 touchcsreen controller driver has been updated to support generic device properties and work with mms152 cntrollers - Goodix driver now supports generic touchscreen properties - couple of drivers for AVR32 architecture are gone as the architecture support has been removed from the kernel - gpio-tilt driver has been removed as there are no mainline users and the driver itself is using legacy APIs and relies on platform data - MODULE_LINECSE/MODULE_VERSION cleanups * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input: (45 commits) Input: goodix - use generic touchscreen_properties Input: mms114 - fix typo in definition Input: mms114 - use BIT() macro instead of explicit shifting Input: mms114 - replace mdelay with msleep Input: mms114 - add support for mms152 Input: mms114 - drop platform data and use generic APIs Input: mms114 - mark as direct input device Input: mms114 - do not clobber interrupt trigger Input: edt-ft5x06 - fix error handling for factory mode on non-M06 Input: stmfts - set IRQ_NOAUTOEN to the irq flag Input: auo-pixcir-ts - delete an unnecessary return statement Input: auo-pixcir-ts - remove custom log for a failed memory allocation Input: da9052_tsi - remove unused mutex Input: docs - use PROPERTY_ENTRY_U32() directly Input: synaptics-rmi4 - log when we create a guest serio port Input: synaptics-rmi4 - unmask F03 interrupts when port is opened Input: synaptics-rmi4 - do not delete interrupt memory too early Input: ad7877 - use managed resource allocations Input: stmfts,s6sy671 - add SPDX identifier Input: remove atmel-wm97xx touchscreen driver ...
2018-01-21gpio: Fix a documentation spelling mistakeLinus Walleij1-1/+1
Simple etraneous letter. Reported-by: Alexander Stein <alexander.stein@systec-electronic.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-01-18gpio: Documentation updateLinus Walleij4-46/+88
Update a slew of documentation files with the latest changes in the API/ABI. Again stress that sysfs is deprecated. Add all new flags and clean up and move some text. Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-01-09Documentation: gpio: correct return value of gpiod_get_directionWolfram Sang1-1/+1
The use of the GPIOF_* flags is deprecated, so don't advertise them here. Document the plain numbers for now until we have a better solution. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-01-02Input: gpio_tilt - delete driverLinus Walleij1-5/+0
This driver was merged in 2011 as a tool for detecting the orientation of a screen. The device driver assumes board file setup using the platform data from <linux/input/gpio_tilt.h>. But no boards in the kernel tree defines this platform data. As I am faced with refactoring drivers to use GPIO descriptors and pass decriptor tables from boards, or use the device tree device drivers like these creates a serious problem: I cannot fix them and cannot test them, not even compile-test them with a system actually using it (no in-tree boardfile). I suggest to delete this driver and rewrite it using device tree if it is still in use on actively maintained systems. I can also offer to rewrite it out of the blue using device tree if someone promise to test it and help me iterate it. Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Acked-by: Heiko Stuebner <heiko@sntech.de> Patchwork-Id: 10133609 Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2017-11-09Merge branch 'gpio-irqchip-rework' of /home/linus/linux-gpio into develLinus Walleij2-17/+52
2017-11-08gpio: Move irq_valid_mask into struct gpio_irq_chipThierry Reding1-2/+2
In order to consolidate the multiple ways to associate an IRQ chip with a GPIO chip, move more fields into the new struct gpio_irq_chip. Signed-off-by: Thierry Reding <treding@nvidia.com> Acked-by: Grygorii Strashko <grygorii.strashko@ti.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-11-08gpio: Move irqdomain into struct gpio_irq_chipThierry Reding1-1/+1
In order to consolidate the multiple ways to associate an IRQ chip with a GPIO chip, move more fields into the new struct gpio_irq_chip. Signed-off-by: Thierry Reding <treding@nvidia.com> Acked-by: Grygorii Strashko <grygorii.strashko@ti.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-10-19gpio: Introduce ->get_multiple callbackLukas Wunner1-11/+30
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>
2017-09-22pinctrl/gpio: Unify namespace for cross-callsLinus Walleij1-5/+5
The pinctrl_request_gpio() and pinctrl_free_gpio() break the nice namespacing in the other cross-calls like pinctrl_gpio_foo(). Just rename them and all references so we have one namespace with all cross-calls under pinctrl_gpio_*(). Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-09-22Merge tag 'ib-mfd-many-v4.14' of ↵Dmitry Torokhov1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/lee/mfd into next Merge "Immutable branch between MFD and many other subsystems due for the v4.14 merge window" to get the TWL headers moved to the right place.
2017-09-19gpio: Clarify consumer stubs use-casesLinus Walleij1-3/+19
After discussion we add a few blurbs to clarify how the stubs in the consumer API are supposed to be used. Cc: Florian Fainelli <f.fainelli@gmail.com> Cc: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com> Cc: Andrew Lunn <andrew@lunn.ch> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-09-07Merge branch 'for-linus' of ↵Linus Torvalds1-0/+5
git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input Pull input updates from Dmitry Torokhov: - a new GPIO bit-banging driver implementing PS/2 protocol - a new power key driver for Rockchip RK805 PMIC - bunch of patches constifying various device ID structures - Elan I2C touchpad driver now supports devices with 2 buttons - other assorted fixes * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input: (76 commits) Input: byd - make array seq static, reduces object code size Input: xilinx_ps2 - fix multiline comment style Input: pxa27x_keypad - handle return value of clk_prepare_enable Input: tegra-kbc - handle return value of clk_prepare_enable Input: PS/2 gpio bit banging driver for serio bus Input: xen-kbdfront - enable auto repeat for xen keyboard frontend driver Input: ambakmi - constify amba_id Input: atmel_mxt_ts - add support for reset line Input: atmel_mxt_ts - use more managed resources Input: wacom_w8001 - constify serio_device_id Input: tsc40 - constify serio_device_id Input: touchwin - constify serio_device_id Input: touchright - constify serio_device_id Input: touchit213 - constify serio_device_id Input: penmount - constify serio_device_id Input: mtouch - constify serio_device_id Input: inexio - constify serio_device_id Input: hampshire - constify serio_device_id Input: gunze - constify serio_device_id Input: fujitsu_ts - constify serio_device_id ...
2017-08-28Input: PS/2 gpio bit banging driver for serio busDanilo Krummrich1-0/+5
This driver provides PS/2 serio bus support by implementing bit banging with the GPIO API. The GPIO pins, data and clock, can be configured with a node in the device tree or by generic device properties (GDP). Writing to a device is supported as well, though it is possible timings can not be halt as they are tough and difficult to reach with bit banging. Therefore it can be configured (also in DT and GDP) whether the serio write function should be available for clients. This driver is for development purposes and not recommended for productive use. However, this driver can be useful e.g. when no USB port is available or using old peripherals is desired as PS/2 controller chips getting rare. This driver was tested on bcm2825 and on Kirin 960 and it worked well together with the atkbd and psmouse driver. Signed-off-by: Danilo Krummrich <danilokrummrich@dk-develop.de> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Acked-by: Rob Herring <robh@kernel.org> Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2017-08-07pinctrl: generic: update references to Documentation/pinctrl.txtLudovic Desroches1-1/+1
Update deprecated references to Documentation/pinctrl.txt since it has been moved to Documentation/driver-api/pinctl.rst. Signed-off-by: Ludovic Desroches <ludovic.desroches@o2linux.fr> Fixes: 5a9b73832e9e ("pinctrl.txt: move it to the driver-api book") Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-03-15gpio: return NULL from gpiod_get_optional when GPIOLIB is disabledDmitry Torokhov1-0/+6
Given the intent behind gpiod_get_optional() and friends it does not make sense to return -ENOSYS when GPIOLIB is disabled: the driver is expected to work just fine without gpio so let's behave as if gpio was not found. Otherwise we have to special-case -ENOSYS in drivers. Note that there was objection that someone might forget to enable GPIOLIB when dealing with a platform that has device that actually specifies optional gpio and we'll break it. I find this unconvincing as that would have to be the *only GPIO* in the system, which is extremely unlikely. Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-01-31gpio: random documentation updateLinus Walleij1-9/+46
Updated and proofread the documentation for GPIO drivers a bit when looking over the changes for generic configuration. Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-01-26pinctrl / gpio: Introduce .set_config() callback for GPIO chipsMika Westerberg1-4/+5
Currently we already have two pin configuration related callbacks available for GPIO chips .set_single_ended() and .set_debounce(). In future we expect to have even more, which does not scale well if we need to add yet another callback to the GPIO chip structure for each possible configuration parameter. Better solution is to reuse what we already have available in the generic pinconf. To support this, we introduce a new .set_config() callback for GPIO chips. The callback takes a single packed pin configuration value as parameter. This can then be extended easily beyond what is currently supported by just adding new types to the generic pinconf enum. If the GPIO driver is backed up by a pinctrl driver the GPIO driver can just assign gpiochip_generic_config() (introduced in this patch) to .set_config and that will take care configuration requests are directed to the pinctrl driver. We then convert the existing drivers over .set_config() and finally remove the .set_single_ended() and .set_debounce() callbacks. Suggested-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-12-13Merge tag 'gpio-v4.10-1' of ↵Linus Torvalds1-26/+36
git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio Pull GPIO updates from Luinus Walleij: "Bulk GPIO changes for the v4.10 kernel cycle: Core changes: - Simplify threaded interrupt handling: instead of passing numbed parameters to gpiochip_irqchip_add_chained() we create a new call: gpiochip_irqchip_add_nested() so the two types are clearly semantically different. Also make sure that all nested chips call gpiochip_set_nested_irqchip() which is necessary for IRQ resend to work properly if it happens. - Return error on seek operations for the chardev. - Clamp values set as part of gpio[d]_direction_output() so that anything != 0 will be send down to the driver as "1" not the value passed in. - ACPI can now support naming of GPIO lines, hogs and holes in the GPIO lists. New drivers: - The SX150x driver was deemed unfit for the GPIO subsystem and was moved over to a combined GPIO+pinctrl driver in the pinctrl subsystem. New features: - Various cleanups to various drivers" * tag 'gpio-v4.10-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (49 commits) gpio: merrifield: Implement gpio_get_direction callback gpio: merrifield: Add support for hardware debouncer gpio: chardev: Return error for seek operations gpio: arizona: Tidy up probe error path gpio: arizona: Remove pointless set of platform drvdata gpio: pl061: delete platform data handling gpio: pl061: move platform data into driver gpio: pl061: rename variable from chip to pl061 gpio: pl061: rename state container struct gpio: pl061: use local state for parent IRQ storage gpio: set explicit nesting on drivers gpio: simplify adding threaded interrupts gpio: vf610: use builtin_platform_driver gpio: axp209: use correct register for GPIO input status gpio: stmpe: fix interrupt handling bug gpio: em: depnd on ARCH_SHMOBILE gpio: zx: depend on ARCH_ZX gpio: x86: update config dependencies for x86 specific hardware gpio: mb86s7x: use builtin_platform_driver gpio: etraxfs: use builtin_platform_driver ...
2016-11-25gpio: simplify adding threaded interruptsLinus Walleij1-26/+36
This tries to simplify the use of CONFIG_GPIOLIB_IRQCHIP when using threaded interrupts: add a new call gpiochip_irqchip_add_nested() to indicate that we're dealing with a nested rather than a chained irqchip, then create a separate gpiochip_set_nested_irqchip() to mirror the gpiochip_set_chained_irqchip() call to connect the parent and child interrupts. In the nested case gpiochip_set_nested_irqchip() does nothing more than call irq_set_parent() on each valid child interrupt, which has little semantic effect in the kernel, but this is probably still formally correct. Update all drivers using nested interrupts to use gpiochip_irqchip_add_nested() so we can now see clearly which these users are. The DLN2 driver can drop its specific hack with .irq_not_threaded as we now recognize whether a chip is threaded or not from its use of gpiochip_irqchip_add_nested() signature rather than from inspecting .can_sleep. We rename the .irq_parent to .irq_chained_parent since this parent IRQ is only really kept around for the chained interrupt handlers. Cc: Lars Poeschel <poeschel@lemonage.de> Cc: Octavian Purdila <octavian.purdila@intel.com> Cc: Daniel Baluta <daniel.baluta@intel.com> Cc: Bin Gao <bin.gao@linux.intel.com> Cc: Mika Westerberg <mika.westerberg@linux.intel.com> Cc: Ajay Thomas <ajay.thomas.david.rajamanickam@intel.com> Cc: Semen Protsenko <semen.protsenko@globallogic.com> Cc: Alexander Stein <alexander.stein@systec-electronic.com> Cc: Phil Reid <preid@electromag.com.au> Cc: Bartosz Golaszewski <bgolaszewski@baylibre.com> Cc: Patrice Chotard <patrice.chotard@st.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-10-20gpio/board.txt: point to gpiod_set_valuePavel Machek1-4/+7
gpiod_set_value() is preffered interface these days, so add a pointer. Also fix a missing ). Signed-off-by: Pavel Machek <pavel@ucw.cz> [Fixed some grammar and reworded] Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-09-23Merge branch 'gpio-irq-validmask' of /home/linus/linux-pinctrl into develLinus Walleij1-0/+6
2016-09-23gpiolib: Make it possible to exclude GPIOs from IRQ domainMika Westerberg1-0/+6
When using GPIO irqchip helpers to setup irqchip for a gpiolib based driver, it is not possible to select which GPIOs to add to the IRQ domain. Instead it just adds all GPIOs which is not always desired. For example there might be GPIOs that for some reason cannot generated normal interrupts at all. To support this we add a flag irq_need_valid_mask to struct gpio_chip. When this flag is set the core allocates irq_valid_mask that holds one bit for each GPIO the chip has. By default all bits are set but drivers can manipulate this using set_bit() and clear_bit() accordingly. Then when gpiochip_irqchip_add() is called, this mask is checked and all GPIOs with bit is set are added to the IRQ domain created for the GPIO chip. Suggested-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-08-08gpio: delete ARCH_[WANTS_OPTIONAL|REQUIRE]_GPIOLIBLinus Walleij2-15/+7
The GPIOLIB is now selectable explicitly, and always available for all archs. All archs that require GPIOLIB are switched to select GPIOLIB directly. Delete the hairy ARCH_REQUIRE_GPIOLIB and ARCH_WANTS_OPTIONAL_GPIOLIB Kconfig symbols. Cc: Michael Büsch <m@bues.ch> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-06-13gpio: Fix paths to GPIO driver source filesAndrew Jeffery1-6/+7
Signed-off-by: Andrew Jeffery <andrew@aj.id.au> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-04-27gpio: clarify open drain/source docsLinus Walleij1-6/+14
Make the text clearer, remove reference to confusing "positive" and "negative" and elaborate a bit. Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-04-09gpio: document open drain/source behaviourLinus Walleij1-0/+89
This has been a totally undocumented feature for years so add some generic concepts and documentation about open drain/source, include some facts on how we now support for hardware. Cc: Michael Hennerich <michael.hennerich@analog.com> Cc: Nicolas Saenz Julienne <nicolassaenzj@gmail.com> Cc: H. Nikolaus Schaller <hns@goldelico.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-02-25gpio: documenatation: fix GPIO_LOOKUP{,_IDX} documentationGabor Juhos1-6/+5
The 'dev_id' parameter of the GPIO_LOOKUP{,_IDX} macros were removed by commit ad824783fb23 ("gpio: better lookup method for platform GPIOs"). Update the documentation to reflect that. Signed-off-by: Gabor Juhos <juhosg@openwrt.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-11-21Doc: gpio: Fix typos in Documentation/gpioMasanari Iida3-7/+7
This patch fix some spelling typos found in Documentation/gpio. Signed-off-by: Masanari Iida <standby24x7@gmail.com> Acked-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2015-11-06Merge tag 'docs-for-linus' of git://git.lwn.net/linuxLinus Torvalds2-6/+10
Pull documentation update from Jon Corbet: "There is a nice new document from Neil on how pathname lookups work and some new CAN driver documentation. Beyond that, we have kernel-doc fixes, a bit more work to support reproducible builds, and the usual collection of small fixes" * tag 'docs-for-linus' of git://git.lwn.net/linux: (34 commits) Documentation: add new description of path-name lookup. Documentation/vm/slub.txt: document slabinfo-gnuplot.sh Doc: ABI/stable: Fix typo in ABI/stable doc: Clarify that nmi_watchdog param is for hardlockups Typo correction for description in gpio document. DocBook: Fix kernel-doc to be case-insensitive for private: kernel-docs.txt: update kernelnewbies reference Doc:kvm: Fix typo in Doc/virtual/kvm Documentation/Changes: Add bc in "Current Minimal Requirements" section Documentation/email-clients.txt: remove trailing whitespace DocBook: Use a fixed encoding for output MAINTAINERS: The docs tree has moved Docs/kernel-parameters: Add earlycon devicetree usage SubmittingPatches: make Subject examples match the de facto standard Documentation: gpio: mention that <function>-gpio has been deprecated Documentation: cgroups: just fix a few typos Documentation: Update kselftest.txt Documentation: DMA API: Be more explicit that nents is always the same Documentation: Update the default value of crashkernel low zram: update documentation ...
2015-10-27gpio: add a real time compliance notesGrygorii Strashko1-0/+80
Put in a compliance checklist. Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-10-27Revert "gpio: add a real time compliance checklist"Linus Walleij1-60/+12
This reverts commit 677b2ff4afd9996eabefc9472c701211b4b49e87.
2015-10-20gpio: add a real time compliance checklistLinus Walleij1-12/+60
Add some information about real time compliance to the driver document. Inspired by Grygorii Strashko's real time compliance patches. Cc: Grygorii Strashko <grygorii.strashko@ti.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-10-12Typo correction for description in gpio document.Sachin Pandhare1-3/+3
Corrected Documentation/gpio/sysfs.txt for typos and wording. typos: syfs -> sysfs, manges -> manages wording: entry -> entries Signed-off-by: Sachin Pandhare <sachinpandhare@gmail.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2015-09-25Documentation: gpio: mention that <function>-gpio has been deprecatedJavier Martinez Canillas1-3/+7
The gpiolib supports parsing DT properties of the form <function>-gpio but it was only added for compatibility with older DT bindings that got it wrong and should not be used in newer bindings. The commit that added support for this was: dd34c37aa3e8 ("gpio: of: Allow -gpio suffix for property names") but didn't update the documentation to explain this so it's been a source of confusion. So let's make clear this in the GPIO documentation. Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2015-09-14Documentation: gpio: Explain that <function>-gpio is also supportedJavier Martinez Canillas1-3/+3
The GPIO documentation mentions that GPIOs are mapped by defining a <function>-gpios property in the consumer device's node but a -gpio sufix is also supported after commit: dd34c37aa3e8 ("gpio: of: Allow -gpio suffix for property names") Update the documentation to match the implementation. Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-09-14Documentation: gpio: board: describe the con_id parameterDirk Behme2-0/+12
The con_id parameter has to match the GPIO description and is automatically extended by the GPIO suffix if not NULL. I had to look into the code to understand this and properly find the GPIO I've been looking for, so document this. Signed-off-by: Dirk Behme <dirk.behme@gmail.com> Acked-by: Alexandre Courbot <acourbot@nvidia.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-09-14Documentation: gpio: board: add flags parameter to gpiod_get*() functionsDirk Behme1-12/+13
With commit 39b2bbe3d715 ("gpio: add flags argument to gpiod_get*() functions") the gpiod_get*() functions got a 'flags' parameter. Reflect this in the documentation, too. Signed-off-by: Dirk Behme <dirk.behme@gmail.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-08-17Documentation: gpio: consumer: describe active low propertyDirk Behme1-0/+33
I've been searching for any documentation of 'the active-low property of a GPIO' already mentioned in this documenation. But couldn't find any. Add it. Sigend-off-by: Dirk Behme <dirk.behme@gmail.com> Acked-by: Alexandre Courbot <acourbot@nvidia.com> [Spelling, grammar fixes] Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-07-21gpio: document interaction with other subsystemsLinus Walleij3-5/+102
Now I am very fed up with people reinventing kernel wheels in userspace "just because they can" (read, sysfs). Put in a angry blurb in sysfs doc and put in a new file with pointers to other subsystem drivers utilizing GPIOs. Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-06-25Merge tag 'docs-for-linus' of git://git.lwn.net/linux-2.6Linus Torvalds1-1/+1
Pull documentation updates from Jonathan Corbet: "The main thing here is Ingo's big subdirectory documenting feature support for each architecture. Beyond that, it's the usual pile of fixes, tweaks, and small additions" * tag 'docs-for-linus' of git://git.lwn.net/linux-2.6: (79 commits) doc:md: fix typo in md.txt. Documentation/mic/mpssd: don't build x86 userspace when cross compiling Documentation/prctl: don't build tsc tests when cross compiling Documentation/vDSO: don't build tests when cross compiling Doc:ABI/testing: Fix typo in sysfs-bus-fcoe Doc: Docbook: Change wikipedia's URL from http to https in scsi.tmpl Doc: Change wikipedia's URL from http to https Documentation/kernel-parameters: add missing pciserial to the earlyprintk Doc:pps: Fix typo in pps.txt kbuild : Fix documentation of INSTALL_HDR_PATH Documentation: filesystems: updated struct file_operations documentation in vfs.txt kbuild: edit explanation of clean-files variable Doc: ja_JP: Fix typo in HOWTO Move freefall program from Documentation/ to tools/ Documentation: ARM: EXYNOS: Describe boot loaders interface Doc:nfc: Fix typo in nfc-hci.txt vfs: Minor documentation fix Doc: networking: txtimestamp: fix printf format warning Documentation, intel_pstate: Improve legacy mode internal governors description Documentation: extend use case for EXPORT_SYMBOL_GPL() ...
2015-06-04fix documentation after renaming gpiod_set_array to gpiod_set_array_valueRojhalat Ibrahim1-14/+14
Patch "gpiolib: rename gpiod_set_array to gpiod_set_array_value" omitted to also change the function names in the documentation. Let's fix that. Signed-off-by: Rojhalat Ibrahim <imr@rtschenk.de> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-05-22gpiolib: Grammar s/an negative/a negative/Geert Uytterhoeven1-1/+1
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2015-05-12gpio: remove gpiod_sysfs_set_active_lowJohan Hovold2-17/+0
Remove gpiod_sysfs_set_active_low (and gpio_sysfs_set_active_low) which allowed code to change the polarity of a gpio line even after it had been exported through sysfs. Drivers should not care, and generally does not know, about gpio-line polarity which is a hardware feature that needs to be described by firmware. It is currently possible to define gpio-line polarity in device-tree and acpi firmware or using platform data. Userspace can also change the polarity through sysfs. Note that drivers using the legacy gpio interface could still use GPIOF_ACTIVE_LOW to change the polarity before exporting the gpio. There are no in-kernel users of this interface. Cc: Jonathan Corbet <corbet@lwn.net> Cc: Harry Wei <harryxiyou@gmail.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: linux-doc@vger.kernel.org Cc: linux-kernel@zh-kernel.org Cc: linux-arch@vger.kernel.org Signed-off-by: Johan Hovold <johan@kernel.org> Reviewed-by: Alexandre Courbot <acourbot@nvidia.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>