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2014-12-14Merge tag 'gpio-v3.19-2' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpioLinus Torvalds1-0/+27
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>
2014-08-29Documentation: 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>
2014-06-04Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial into nextLinus Torvalds1-1/+1
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>
2014-02-07gpio: 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>
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>
2013-11-25Documentation: gpiolib: document new interfaceAlexandre Courbot1-0/+197
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>