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2015-06-24Merge 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>
2015-04-18Merge tag 'docs-for-linus' of git://git.lwn.net/linux-2.6Linus Torvalds1-4/+37
Pull documentation updates from Jonathan Corbet: "Numerous fixes, the overdue removal of the i2o docs, some new Chinese translations, and, hopefully, the README fix that will end the flow of identical patches to that file" * tag 'docs-for-linus' of git://git.lwn.net/linux-2.6: (34 commits) Documentation/memcg: update memcg/kmem status Documentation: blackfin: Makefile: Typo building issue Documentation/vm/pagemap.txt: correct location of page-types tool Documentation/memory-barriers.txt: typo fix doc: Add guest_nice column to example output of `cat /proc/stat' Documentation/kernel-parameters: Move "eagerfpu" to its right place Documentation: gpio: Update ACPI part of the document to mention _DSD docs/completion.txt: Various tweaks and corrections doc: completion: context, scope and language fixes Documentation:Update Documentation/zh_CN/arm64/memory.txt Documentation:Update Documentation/zh_CN/arm64/booting.txt Documentation: Chinese translation of arm64/legacy_instructions.txt DocBook media: fix broken EIA hyperlink Documentation: tweak the maintainers entry README: Change gzip/bzip2 to xz compression format README: Update version number reference doc:pci: Fix typo in Documentation/PCI Documentation: drm: Use '->' when describing access through pointers. Documentation: Remove mentioning of block barriers Documentation/email-clients.txt: Fix one grammar mistake, add extra info about TB ...
2015-04-04Documentation: gpio: Update ACPI part of the document to mention _DSDMika Westerberg1-4/+37
With ACPI 5.1 _DSD (Device Specific Data) it is now possible to name functions just like Device Tree is doing. Make sure that the documentation mentions _DSD as the recommended way to describe GPIOs in ACPI systems. Reported-by: Darren Hart <dvhart@linux.intel.com> Reviewed-by: Darren Hart <dvhart@linux.intel.com> Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2015-03-09extend documentation for gpiod_set_array() functionsRojhalat Ibrahim1-0/+20
Extend the documentation for the gpiod_set_array() functions and elaborate a bit on possible use cases. Signed-off-by: Rojhalat Ibrahim <imr@rtschenk.de> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-03-05gpiolib: add devm_gpiod_get_array and devm_gpiod_put_array functionsRojhalat Ibrahim1-2/+12
Add device managed variants of gpiod_get_array() / gpiod_put_array() functions for conveniently obtaining and disposing of an entire array of GPIOs with one function call. Signed-off-by: Rojhalat Ibrahim <imr@rtschenk.de> Reviewed-by: Alexandre Courbot <acourbot@nvidia.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-03-05gpiolib: add gpiod_get_array and gpiod_put_array functionsRojhalat Ibrahim1-3/+30
Introduce new functions for conveniently obtaining and disposing of an entire array of GPIOs with one function call. ACPI parts tested by Mika Westerberg, DT parts tested by Rojhalat Ibrahim. Change log: v5: move the ACPI functions to gpiolib-acpi.c v4: - use shorter names for members of struct gpio_descs - rename lut_gpio_count to platform_gpio_count for clarity - add check for successful memory allocation - use ERR_CAST() v3: - rebase on current linux-gpio devel branch - fix ACPI GPIO counting - allow for zero-sized arrays - make the flags argument mandatory for the new functions - clarify documentation v2: change interface Suggested-by: Alexandre Courbot <acourbot@nvidia.com> Signed-off-by: Rojhalat Ibrahim <imr@rtschenk.de> Reviewed-by: Alexandre Courbot <acourbot@nvidia.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com> Tested-by: Rojhalat Ibrahim <imr@rtschenk.de> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-01-28gpio: board.txt: Fix the gpio name exampleFabio Estevam1-1/+1
As explained in this file: "GPIOs mappings are defined in the consumer device's node, in a property named <function>-gpios" So fix the example to match the convention. Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com> Acked-by: Alexandre Courbot <acourbot@nvidia.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2014-12-14Merge tag 'gpio-v3.19-2' of ↵Linus Torvalds2-2/+29
git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio Pull take two of the GPIO updates: "Same stuff as last time, now with a fixup patch for the previous compile error plus I ran a few extra rounds of compile-testing. This is the bulk of GPIO changes for the v3.19 series: - A new API that allows setting more than one GPIO at the time. This is implemented for the new descriptor-based API only and makes it possible to e.g. toggle a clock and data line at the same time, if the hardware can do this with a single register write. Both consumers and drivers need new calls, and the core will fall back to driving individual lines where needed. Implemented for the MPC8xxx driver initially - Patched the mdio-mux-gpio and the serial mctrl driver that drives modems to use the new multiple-setting API to set several signals simultaneously - Get rid of the global GPIO descriptor array, and instead allocate descriptors dynamically for each GPIO on a certain GPIO chip. This moves us closer to getting rid of the limitation of using the global, static GPIO numberspace - New driver and device tree bindings for 74xx ICs - New driver and device tree bindings for the VF610 Vybrid - Support the RCAR r8a7793 and r8a7794 - Guidelines for GPIO device tree bindings trying to get things a bit more strict with the advent of combined device properties - Suspend/resume support for the MVEBU driver - A slew of minor fixes and improvements" * tag 'gpio-v3.19-2' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (33 commits) gpio: mcp23s08: fix up compilation error gpio: pl061: document gpio-ranges property for bindings file gpio: pl061: hook request if gpio-ranges avaiable gpio: mcp23s08: Add option to configure IRQ output polarity as active high gpio: fix deferred probe detection for legacy API serial: mctrl_gpio: use gpiod_set_array function mdio-mux-gpio: Use GPIO descriptor interface and new gpiod_set_array function gpio: remove const modifier from gpiod_get_direction() gpio: remove gpio_descs global array gpio: mxs: implement get_direction callback gpio: em: Use dynamic allocation of GPIOs gpio: Check if base is positive before calling gpio_is_valid() gpio: mcp23s08: Add simple IRQ support for SPI devices gpio: mcp23s08: request a shared interrupt gpio: mcp23s08: Do not free unrequested interrupt gpio: rcar: Add r8a7793 and r8a7794 support gpio-mpc8xxx: add mpc8xxx_gpio_set_multiple function gpiolib: allow simultaneous setting of multiple GPIO outputs gpio: mvebu: add suspend/resume support gpio: gpio-davinci: remove duplicate check on resource ..
2014-11-27gpiolib: allow simultaneous setting of multiple GPIO outputsRojhalat Ibrahim1-0/+27
Introduce new functions gpiod_set_array & gpiod_set_raw_array to the consumer interface which allow setting multiple outputs with just one function call. Also add an optional set_multiple function to the driver interface. Without an implementation of that function in the chip driver outputs are set sequentially. Implementing the set_multiple function in a chip driver allows for: - Improved performance for certain use cases. The original motivation for this was the task of configuring an FPGA. In that specific case, where 9 GPIO lines have to be set many times, configuration time goes down from 48 s to 20 s when using the new function. - Simultaneous glitch-free setting of multiple pins on any kind of parallel bus attached to GPIOs provided they all reside on the same chip and bank. Limitations: Performance is only improved for normal high-low outputs. Open drain and open source outputs are always set separately from each other. Those kinds of outputs could probably be accelerated in a similar way if we could forgo the error checking when setting GPIO directions. Change log: v6: - rebase on current linux-gpio devel branch v5: - check can_sleep property per chip - remove superfluous checks - supplement documentation v4: - add gpiod_set_array function for setting logical values - change interface of the set_multiple driver function to use unsigned long as type for the bit fields - use generic bitops (which also use unsigned long for bit fields) - do not use ARCH_NR_GPIOS any more v3: - add documentation - change commit message v2: - use descriptor interface - allow arbitrary groups of GPIOs spanning multiple chips Signed-off-by: Rojhalat Ibrahim <imr@rtschenk.de> Reviewed-by: Alexandre Courbot <acourbot@nvidia.com> Reviewed-by: Mark Brown <broonie@linaro.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-11-04ACPI / GPIO: Document ACPI GPIO mappings APIRafael J. Wysocki1-0/+18
Document the previously introduced method that can be used by device drivers to provide the GPIO subsystem with mappings between GPIO names (connection IDs) and GpioIo()/GpioInt() resources in _CRS. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
2014-10-28gpio: rename gpio_lock_as_irq to gpiochip_lock_as_irqAlexandre Courbot1-2/+2
This function actually operates on a gpio_chip, so its prefix should reflect that fact for consistency with other functions defined in gpio/driver.h. Signed-off-by: Alexandre Courbot <acourbot@nvidia.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-10-09Merge tag 'gpio-v3.18-1' of ↵Linus Torvalds1-2/+4
git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio Pull GPIO changes from Linus Walleij: "This is the bulk of GPIO changes for the v3.18 development cycle: - Increase the default ARCH_NR_GPIO from 256 to 512. This was done to avoid having a custom <asm/gpio.h> header for the x86 architecture - GPIO is custom and complicated enough as it is already! We want to move to a radix to store the descriptors going forward, and finally get rid of this fixed array size altogether. - Endgame patching of the gpio_remove() semantics initiated by Abdoulaye Berthe. It is not accepted by the system that the removal of a GPIO chip fails during eg reboot or shutdown, and therefore the return value has now painfully been refactored away. For special cases like GPIO expanders on a hot-pluggable bus like USB, we may later add some gpiochip_try_remove() call, but for the cases we have now, return values are moot. - Some incremental refactoring of the gpiolib core and ACPI GPIO library for more descriptor usage. - Refactor the chained IRQ handler set-up method to handle also threaded, nested interrupts and set up the parent IRQ correctly. Switch STMPE and TC3589x drivers to use this registration method. - Add a .irq_not_threaded flag to the struct gpio_chip, so that also GPIO expanders that block but are still not using threaded IRQ handlers. - New drivers for the ARM64 X-Gene SoC GPIO controller. - The syscon GPIO driver has been improved to handle the "DSP GPIO" found on the TI Keystone 2 SoC:s. - ADNP driver switched to use gpiolib irqchip helpers. - Refactor the DWAPB driver to support being instantiated from and MFD cell (platform device). - Incremental feature improvement in the Zynq, MCP23S08, DWAPB, OMAP, Xilinx and Crystalcove drivers. - Various minor fixes" * tag 'gpio-v3.18-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (52 commits) gpio: pch: Build context save/restore only for PM pinctrl: abx500: get rid of unused variable gpio: ks8695: fix 'else should follow close brace '}'' gpio: stmpe: add verbose debug code gpio: stmpe: fix up interrupt enable logic gpio: staticize xway_stp_init() gpio: handle also nested irqchips in the chained handler set-up gpio: set parent irq on chained handlers gpiolib: irqchip: use irq_find_mapping while removing irqchip gpio: crystalcove: support virtual GPIO pinctrl: bcm281xx: make Kconfig dependency more strict gpio: kona: enable only on BCM_MOBILE or for compile testing gpio, bcm-kona, LLVMLinux: Remove use of __initconst gpio: Fix ngpio in gpio-xilinx driver gpio: dwapb: fix pointer to integer cast gpio: xgene: Remove unneeded #ifdef CONFIG_OF guard gpio: xgene: Remove unneeded forward declation for struct xgene_gpio gpio: xgene: Fix missing spin_lock_init() gpio: ks8695: fix switch case indentation gpiolib: add irq_not_threaded flag to gpio_chip ...
2014-09-26gpio: handle also nested irqchips in the chained handler set-upLinus Walleij1-1/+2
To unify how we connect cascaded IRQ chips to parent IRQs, if NULL us passed as handler to the gpiochip_set_chained_irqchip() function, assume the chips is nested rather than chained, and we still get the parent set up correctly by way of this function call. Alter the drivers for tc3589x and stmpe to use this to set up their chained handlers as a demonstration of the usage. Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-08-29gpio: change gpiochip_request_own_desc() prototypeAlexandre Courbot1-1/+2
The current prototype of gpiochip_request_own_desc() requires to obtain a pointer to a descriptor. This is in contradiction to all other GPIO request schemes, and imposes an extra step of obtaining a descriptor to drivers. Most drivers actually cannot even perform that step since the function that does it (gpichip_get_desc()) is gpiolib-private. Change gpiochip_request_own_desc() to return a descriptor from a (chip, hwnum) tuple and update users of this function (currently gpiolib-acpi only). Signed-off-by: Alexandre Courbot <acourbot@nvidia.com> Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-08-29Documentation: gpio: documentation for optional getters functionsAlexandre Courbot1-1/+23
Add a mention about the _optional variants of (devm_)gpiod_get*(). Signed-off-by: Alexandre Courbot <acourbot@nvidia.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-07-28gpio: add flags argument to gpiod_get*() functionsAlexandre Courbot1-6/+20
The huge majority of GPIOs have their direction and initial value set right after being obtained by one of the gpiod_get() functions. The integer GPIO API had gpio_request_one() that took a convenience flags parameter allowing to specify an direction and value applied to the returned GPIO. This feature greatly simplifies client code and ensures errors are always handled properly. A similar feature has been requested for the gpiod API. Since setting the direction of a GPIO is so often the very next action done after obtaining its descriptor, we prefer to extend the existing functions instead of introducing new functions that would raise the number of gpiod getters to 16 (!). The drawback of this approach is that all gpiod clients need to be updated. To limit the pain, temporary macros are introduced that allow gpiod_get*() to be called with or without the extra flags argument. They will be removed once all consumer code has been updated. Signed-off-by: Alexandre Courbot <acourbot@nvidia.com> Reviewed-by: Mark Brown <broonie@linaro.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-07-28gpio: split gpiod board registration into machine headerLinus Walleij1-1/+1
As per example from the regulator subsystem: put all defines and functions related to registering board info for GPIO descriptors into a separate <linux/gpio/machine.h> header. Cc: Andrew Victor <linux@maxim.org.za> Cc: Nicolas Ferre <nicolas.ferre@atmel.com> Cc: Jean-Christophe Plagniol-Villard <plagnioj@jcrosoft.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Thierry Reding <thierry.reding@gmail.com> Acked-by: Stephen Warren <swarren@wwwdotorg.org> Reviewed-by: Alexandre Courbot <gnurou@gmail.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-07-24gpiolib: Export gpiochip_request_own_desc and gpiochip_free_own_descGuenter Roeck1-0/+21
Both functions were introduced to let gpio drivers request their own gpio pins. Without exporting the functions, this can however only be used by gpio drivers built into the kernel. Secondary impact is that the functions can not currently be used by platform initialization code associated with the gpio-pca953x driver. This code permits auto-export of gpio pins through platform data, but if this functionality is used, the module can no longer be unloaded due to the problem solved with the introduction of gpiochip_request_own_desc and gpiochip_free_own_desc. Export both function so they can be used from modules and from platform initialization code. Reviewed-by: Alexandre Courbot <acourbot@nvidia.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-07-23gpio: remove gpiod_lock/unlock_as_irq()Alexandre Courbot1-2/+2
gpio_lock/unlock_as_irq() are working with (chip, offset) arguments and are thus not using the old integer namespace. Therefore, there is no reason to have gpiod variants of these functions working with descriptors, especially since the (chip, offset) tuple is more suitable to the users of these functions (GPIO drivers, whereas GPIO descriptors are targeted at GPIO consumers). Signed-off-by: Alexandre Courbot <acourbot@nvidia.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-06-04Merge branch 'for-linus' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial into next Pull trivial tree changes from Jiri Kosina: "Usual pile of patches from trivial tree that make the world go round" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (23 commits) staging: go7007: remove reference to CONFIG_KMOD aic7xxx: Remove obsolete preprocessor define of: dma: doc fixes doc: fix incorrect formula to calculate CommitLimit value doc: Note need of bc in the kernel build from 3.10 onwards mm: Fix printk typo in dmapool.c modpost: Fix comment typo "Modules.symvers" Kconfig.debug: Grammar s/addition/additional/ wimax: Spelling s/than/that/, wording s/destinatary/recipient/ aic7xxx: Spelling s/termnation/termination/ arm64: mm: Remove superfluous "the" in comment of: Spelling s/anonymouns/anonymous/ dma: imx-sdma: Spelling s/determnine/determine/ ath10k: Improve grammar in comments ath6kl: Spelling s/determnine/determine/ of: Improve grammar for of_alias_get_id() documentation drm/exynos: Spelling s/contro/control/ radio-bcm2048.c: fix wrong overflow check doc: printk-formats: do not mention casts for u64/s64 doc: spelling error changes ...
2014-05-05doc: spelling error changesCarlos Garcia1-1/+1
Fixed multiple spelling errors. Acked-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Carlos E. Garcia <carlos@cgarcia.org> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2014-04-28gpio: document gpio irqchips a bit more, describe helpersLinus Walleij1-0/+59
This adds some documentation about the GPIO irqchips, what types exist etc. Acked-by: Alexandre Courbot <acourbot@nvidia.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-02-07gpio: make gpiod_direction_output take a logical valuePhilipp Zabel1-0/+1
The documentation was not clear about whether gpio_direction_output should take a logical value or the physical level on the output line, i.e. whether the ACTIVE_LOW status would be taken into account. This converts gpiod_direction_output to use the logical level and adds a new gpiod_direction_output_raw for the raw value. Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de> Reviewed-by: Alexandre Courbot <acourbot@nvidia.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-02-03gpio: document how to make combined GPIO+irqchip driversLinus Walleij1-0/+35
Write a few words on how GPIO drivers supplying an irqchip should be written. Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2013-12-12gpiolib: return -ENOENT if no GPIO mapping existsAlexandre Courbot1-1/+5
Some devices drivers make use of optional GPIO parameters. For such drivers, it is important to discriminate between the case where no GPIO mapping has been defined for the function they are requesting, and the case where a mapping exists but an error occured while resolving it or when acquiring the GPIO. This patch changes the family of gpiod_get() functions such that they will return -ENOENT if and only if no GPIO mapping is defined for the requested function. Other error codes are used when an actual error occured during the GPIO resolution. Signed-off-by: Alexandre Courbot <acourbot@nvidia.com> Reviewed-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>
2013-12-09gpio: better lookup method for platform GPIOsAlexandre Courbot1-11/+17
Change the format of the platform GPIO lookup tables to make them less confusing and improve lookup efficiency. The previous format was a single linked-list that required to compare the device name and function ID of every single GPIO defined for each lookup. Switch that to a list of per-device tables, so that the lookup can be done in two steps, omitting the GPIOs that are not relevant for a particular device. The matching rules are now defined as follows: - The device name must match *exactly*, and can be NULL for GPIOs not assigned to a particular device, - If the function ID in the lookup table is NULL, the con_id argument of gpiod_get() will not be used for lookup. However, if it is defined, it must match exactly. - The index must always match. Signed-off-by: Alexandre Courbot <acourbot@nvidia.com> Acked-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>
2013-12-03Documentation: gpiolib: add 00-INDEX fileAlexandre Courbot1-0/+14
Give a short overview of the various GPIO documentation files. Signed-off-by: Alexandre Courbot <acourbot@nvidia.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2013-11-25Documentation: gpiolib: document new interfaceAlexandre Courbot6-0/+1436
gpiolib now exports a new descriptor-based interface which deprecates the older integer-based one. This patch documents this new interface and also takes the opportunity to brush-up the GPIO documentation a little bit. The new descriptor-based interface follows the same consumer/driver model as many other kernel subsystems (e.g. clock, regulator), so its documentation has similarly been splitted into different files. The content of the former documentation has been reused whenever it made sense; however, some of its content did not apply to the new interface anymore and have this been removed. Likewise, new sections like the mapping of GPIOs to devices have been written from scratch. The deprecated legacy-based documentation is still available, untouched, under Documentation/gpio/gpio-legacy.txt. Signed-off-by: Alexandre Courbot <acourbot@nvidia.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>