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path: root/drivers/gpio/gpiolib.h
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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>
2016-10-24gpio: Rework of_gpiochip_set_names() to use device property accessorsMika Westerberg
In order to use "gpio-line-names" property in systems not having DT as their boot firmware, rework of_gpiochip_set_names() to use device property accessors. This reworked function is placed in a separate file making it clear it deals with universal device properties. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-10-03gpio: add missing static inlineLinus Walleij
of_get_named_gpiod_flags() was missing a static inline version when compiling without OF_GPIO. Add this. Reported-by: kbuild test robot <fengguang.wu@intel.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-10-03gpio: OF: localize some gpiochip init functionsLinus Walleij
of_gpiochip_add() and of_gpiochip_remove() are only used locally in the gpio subsystem so move these functions to the local header. Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-10-03gpio: acpi: separation of concernsLinus Walleij
The generic GPIO library directly implement code for acpi_find_gpio() which is only used with CONFIG_ACPI. This was probably done because OF did the same thing, but I removed that so remove this too. Rename the internal acpi_find_gpio() in gpiolib-acpi.c to acpi_populate_gpio_lookup() which seems to be more appropriate anyway so as to avoid a namespace clash with the same function. Make the stub return -ENOENT rather than -ENOSYS (as that is for syscalls!). For some reason the sunxi pin control driver was including the private gpiolib header, it works just fine without it so remove that oneliner. Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-10-03gpio: OF: separation of concernsLinus Walleij
The generic GPIO library directly implement code for of_find_gpio() which is only used with CONFIG_OF and causes compilation problems on archs that do not even have stubs for OF functions, especially on UM that does not implement any IO remap functions. Move the function to gpiolib-of.c, implement a static inline stub in gpiolib.h returning PTR_ERR(-ENOENT) if CONFIG_OF_GPIO is not set and be done with it. Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-04-26gpio: move gpiod_set_array_value_priv()Linus Walleij
This renames gpiod_set_array_value_priv() to gpiod_set_array_value_complex() and moves it to the gpiolib.h private header file so we can reuse it in the subsystem. Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-02-19gpio: store reflect the label to userspaceLinus Walleij
The gpio_chip label is useful for userspace to understand what kind of GPIO chip it is dealing with. Let's store a copy of this label in the gpio_device, add it to the struct passed to userspace for GPIO_GET_CHIPINFO_IOCTL and modify lsgpio to show it. Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-02-16gpio: move the subdriver data pointer into gpio_deviceLinus Walleij
We move to manage this pointer under gpiolib control rather than leave it in the subdevice's gpio_chip. We can not NULL it after gpiochip_remove so at to keep things tight. Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-02-16gpio: move the pin ranges into gpio_deviceLinus Walleij
Instead of keeping this reference to the pin ranges in the client driver-supplied gpio_chip, move it to the internal gpio_device as the drivers have no need to inspect this. Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-02-11gpio: reflect base and ngpio into gpio_deviceLinus Walleij
Some information about the GPIO chip need to stay around also after the gpio_chip has been removed and only the gpio_device persist. The base and ngpio are such things, for example we don't want a new chip arriving to overlap the number space of a dangling gpio_device, and the chardev may still query the device for the number of lines etc. Note that the code that assigns base and insert gpio_device into the global list no longer check for a missing gpio_chip: we respect the number space allocated by any other gpio_device. As a consequence of the gdev being referenced directly from the gpio_desc, we need to verify it differently from all in-kernel API calls that fall through to direct queries to the gpio_chip vtable: we first check that desc is !NULL, then that desc->gdev is !NULL, then, if desc->gdev->chip is NULL, we *BAIL OUT* without any error, so as to manage the case where operations are requested on a device that is gone. These checks were non-uniform and partly missing in the past: so to simplify: create the macros VALIDATE_DESC() that will return -EINVAL if the desc or desc->gdev is missing and just 0 if the chip is gone, and conversely VALIDATE_DESC_VOID() for the case where the function does not return an error. By using these macros, we get warning messages about missing gdev with reference to the right function in the kernel log. Despite the macro business this simplifies the code and make it more readable than if we copy/paste the same descriptor checking code into all code ABI call sites (IMHO). Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-02-11gpio: move descriptors into gpio_deviceLinus Walleij
We need gpio_device to hold the descriptors so that they can be lifecycled with the struct gpio_device held from userspace. Move the descriptor array into gpio_device. Also rename it from "desc" (singularis) to "descs" (pluralis) to reflect the fact that it is an array. Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-02-11gpio: move sysfs mock device to the gpio_deviceLinus Walleij
Since gpio_device is the struct that survives if the backing gpio_chip is removed, move the sysfs mock device to this state container so it becomes part of the dangling state of the GPIO device on removal. Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-02-09gpio: add a userspace chardev ABI for GPIOsLinus Walleij
A new chardev that is to be used for userspace GPIO access is added in this patch. It is intended to gradually replace the horribly broken sysfs ABI. Using a chardev has many upsides: - All operations are per-gpiochip, which is the actual device underlying the GPIOs, making us tie in to the kernel device model properly. - Hotpluggable GPIO controllers can come and go, as this kind of problem has been know to userspace for character devices since ages, and if a gpiochip handle is held in userspace we know we will break something, whereas the sysfs is stateless. - The one-value-per-file rule of sysfs is really hard to maintain when you want to twist more than one knob at a time, for example have in-kernel APIs to switch several GPIO lines at the same time, and this will be possible to do with a single ioctl() from userspace, saving a lot of context switching. We also need to add a new bus type for GPIO. This is necessary for example for userspace coldplug, where sysfs is traversed to find the boot-time device nodes and create the character devices in /dev. This new chardev ABI is *non* *optional* and can be counted on to be present in the future, emphasizing the preference of this ABI. The ABI only implements one single ioctl() to get the name and number of GPIO lines of a chip. Even this is debatable: see it as a minimal example for review. This ABI shall be ruthlessly reviewed and etched in stone. The old /sys/class/gpio is still optional to compile in, but will be deprecated. Unique device IDs are created using IDR, which is overkill and insanely scalable, but also well tested. Cc: Johan Hovold <johan@kernel.org> Cc: Michael Welling <mwelling@ieee.org> Cc: Markus Pargmann <mpa@pengutronix.de> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-02-09gpio: refer to gpio device in prints and debugfsLinus Walleij
We use the new struct device inside gpio_chip to related debug prints and warnings, and we also add it to the debugfs dump. Cc: Johan Hovold <johan@kernel.org> Cc: Michael Welling <mwelling@ieee.org> Cc: Markus Pargmann <mpa@pengutronix.de> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-02-09gpio: make the gpiochip a real deviceLinus Walleij
GPIO chips have been around for years, but were never real devices, instead they were piggy-backing on a parent device (such as a platform_device or amba_device) but this was always optional. GPIO chips could also exist without any device at all, with its struct device *parent (ex *dev) pointer being set to null. When sysfs was in use, a mock device would be created, with the optional parent assigned, or just floating orphaned with NULL as parent. If sysfs is active, it will use this device as parent. We now create a gpio_device struct containing a real struct device and move the subsystem over to using that. The list of struct gpio_chip:s is augmented to hold struct gpio_device:s and we find gpio_chips:s by first looking up the struct gpio_device. The struct gpio_device is designed to stay around even if the gpio_chip is removed, so as to satisfy users in userspace that need a backing data structure to hold the state of the session initiated with e.g. a character device even if there is no physical chip anymore. From this point on, gpiochips are devices. Cc: Johan Hovold <johan@kernel.org> Cc: Michael Welling <mwelling@ieee.org> Cc: Markus Pargmann <mpa@pengutronix.de> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-01-17Merge tag 'gpio-v4.5-1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio Pull GPIO updates from Linus Walleij: "Here is the bulk of GPIO changes for v4.5. Notably there are big refactorings mostly by myself, aimed at getting the gpio_chip into a shape that makes me believe I can proceed to preserve state for a proper userspace ABI (character device) that has already been proposed once, but resulted in the feedback that I need to go back and restructure stuff. So I've been restructuring stuff. On the way I ran into brokenness (return code from the get_value() callback) and had to fix it. Also, refactored generic GPIO to be simpler. Some of that is still waiting to trickle down from the subsystems all over the kernel that provide random gpio_chips, I've touched every single GPIO driver in the kernel now, oh man I didn't know I was responsible for so much... Apart from that we're churning along as usual. I took some effort to test and retest so it should merge nicely and we shook out a couple of bugs in -next. Infrastructural changes: - In struct gpio_chip, rename the .dev node to .parent to better reflect the fact that this is not the GPIO struct device abstraction. We will add that soon so this would be totallt confusing. - It was noted that the driver .get_value() callbacks was sometimes reporting negative -ERR values to the gpiolib core, expecting them to be propagated to consumer gpiod_get_value() and gpio_get_value() calls. This was not happening, so as there was a mess of drivers returning negative errors and some returning "anything else than zero" to indicate that a line was active. As some would have bit 31 set to indicate "line active" it clashed with negative error codes. This is fixed by the largeish series clamping values in all drivers with !!value to [0,1] and then augmenting the code to propagate error codes to consumers. (Includes some ACKed patches in other subsystems.) - Add a void *data pointer to struct gpio_chip. The container_of() design pattern is indeed very nice, but we want to reform the struct gpio_chip to be a non-volative, stateless business, and keep states internal to the gpiolib to be able to hold on to the state when adding a proper userspace ABI (character device) further down the road. To achieve this, drivers need a handle at the internal state that is not dependent on their struct gpio_chip() so we add gpiochip_add_data() and gpiochip_get_data() following the pattern of many other subsystems. All the "use gpiochip data pointer" patches transforms drivers to this scheme. - The Generic GPIO chip header has been merged into the general <linux/gpio/driver.h> header, and the custom header for that removed. Instead of having a separate mm_gpio_chip struct for these generic drivers, merge that into struct gpio_chip, simplifying the code and removing the need for separate and confusing includes. Misc improvements: - Stabilize the way GPIOs are looked up from the ACPI legacy specification. - Incremental driver features for PXA, PCA953X, Lantiq (patches from the OpenWRT community), RCAR, Zynq, PL061, 104-idi-48 New drivers: - Add a GPIO chip to the ALSA SoC AC97 driver. - Add a new Broadcom NSP SoC driver (this lands in the pinctrl dir, but the branch is merged here too to account for infrastructural changes). - The sx150x driver now supports the sx1502" * tag 'gpio-v4.5-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (220 commits) gpio: generic: make bgpio_pdata always visible gpiolib: fix chip order in gpio list gpio: mpc8xxx: Do not use gpiochip_get_data() in mpc8xxx_gpio_save_regs() gpio: mm-lantiq: Do not use gpiochip_get_data() in ltq_mm_save_regs() gpio: brcmstb: Allow building driver for BMIPS_GENERIC gpio: brcmstb: Set endian flags for big-endian MIPS gpio: moxart: fix build regression gpio: xilinx: Do not use gpiochip_get_data() in xgpio_save_regs() leds: pca9532: use gpiochip data pointer leds: tca6507: use gpiochip data pointer hid: cp2112: use gpiochip data pointer bcma: gpio: use gpiochip data pointer avr32: gpio: use gpiochip data pointer video: fbdev: via: use gpiochip data pointer gpio: pch: Optimize pch_gpio_get() Revert "pinctrl: lantiq: Implement gpio_chip.to_irq" pinctrl: nsp-gpio: use gpiochip data pointer pinctrl: vt8500-wmt: use gpiochip data pointer pinctrl: exynos5440: use gpiochip data pointer pinctrl: at91-pio4: use gpiochip data pointer ...
2016-01-13Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input Pull input updates from Dmitry Torokhov: - new driver for eGalaxTouch serial touchscreen - new driver for TS-4800 touchscreen - an update for Goodix touchscreen driver - PS/2 mouse module was reworked to limit number of protocols we try on pass-through ports to speed up their detection time - wacom_w8001 touchscreen driver now reports pen and touch via separate instances of input devices - other driver changes * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input: (42 commits) Input: elantech - mark protocols v2 and v3 as semi-mt Input: wacom_w8001 - drop use of ABS_MT_TOOL_TYPE Input: gpio-keys - fix check for disabling unsupported keys Input: omap-keypad - remove dead check Input: ti_am335x_tsc - fix HWPEN interrupt handling Input: omap-keypad - set tasklet data earlier Input: rohm_bu21023 - fix handling of retrying firmware update Input: ALPS - report v3 pinnacle trackstick device only if is present Input: ALPS - detect trackstick presence for v7 protocol Input: pcap_ts - use to_delayed_work Input: bma150 - constify bma150_cfg structure Input: i8042 - add Fujitsu Lifebook U745 to the nomux list Input: egalax_ts_serial - fix potential NULL dereference on error Input: uinput - sanity check on ff_effects_max and EV_FF Input: uinput - rework ABS validation Input: uinput - add new UINPUT_DEV_SETUP and UI_ABS_SETUP ioctl Input: goodix - use "inverted_[xy]" flags instead of "rotated_screen" Input: goodix - add axis swapping and axis inversion support Input: goodix - use goodix_i2c_write_u8 instead of i2c_master_send Input: goodix - add power management support ...
2016-01-01ACPI / gpio: Add irq_type when a GPIO is used as an interruptChristophe RICARD
When a GPIO is used as an interrupt in ACPI, the irq_type was not available for device driver. Make available polarity and triggering information in acpi_find_gpio by renaming acpi_gpio_info field active_low to polarity and adding triggering field (edge/level). For sanity, in gpiolib.c replace info.active_low by "info.polarity == GPIO_ACTIVE_LOW". Set the irq_type if necessary in acpi_dev_gpio_irq_get. Signed-off-by: Christophe Ricard <christophe-h.ricard@st.com> Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-12-13gpiolib: tighten up ACPI legacy gpio lookupsDmitry Torokhov
We should not fall back to the legacy unnamed gpio lookup style if the driver requests gpios with different names, because we'll give out the same gpio twice. Let's keep track of the names that were used for the device and only do the fallback for the first name used. Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-12-11gpio: forward-declare enum gpiod_flagsLinus Walleij
This enum is used in the gpiolib.h header file, yet <linux/gpio/consumer.h> is not included so plainly including this file (and some drivers do) will raise compile problems. Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-11-19gpiolib: tighten up ACPI legacy gpio lookupsDmitry Torokhov
We should not fall back to the legacy unnamed gpio lookup style if the driver requests gpios with different names, because we'll give out the same gpio twice. Let's keep track of the names that were used for the device and only do the fallback for the first name used. Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-11-04Merge tag 'pm+acpi-4.4-rc1-1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull power management and ACPI updates from Rafael Wysocki: "Quite a new features are included this time. First off, the Collaborative Processor Performance Control interface (version 2) defined by ACPI will now be supported on ARM64 along with a cpufreq frontend for CPU performance scaling. Second, ACPI gets a new infrastructure for the early probing of IRQ chips and clock sources (along the lines of the existing similar mechanism for DT). Next, the ACPI core and the generic device properties API will now support a recently introduced hierarchical properties extension of the _DSD (Device Specific Data) ACPI device configuration object. If the ACPI platform firmware uses that extension to organize device properties in a hierarchical way, the kernel will automatically handle it and make those properties available to device drivers via the generic device properties API. It also will be possible to build the ACPICA's AML interpreter debugger into the kernel now and use that to diagnose AML-related problems more efficiently. In the future, this should make it possible to single-step AML execution and do similar things. Interesting stuff, although somewhat experimental at this point. Finally, the PM core gets a new mechanism that can be used by device drivers to distinguish between suspend-to-RAM (based on platform firmware support) and suspend-to-idle (or other variants of system suspend the platform firmware is not involved in) and possibly optimize their device suspend/resume handling accordingly. In addition to that, some existing features are re-organized quite substantially. First, the ACPI-based handling of PCI host bridges on x86 and ia64 is unified and the common code goes into the ACPI core (so as to reduce code duplication and eliminate non-essential differences between the two architectures in that area). Second, the Operating Performance Points (OPP) framework is reorganized to make the code easier to find and follow. Next, the cpufreq core's sysfs interface is reorganized to get rid of the "primary CPU" concept for configurations in which the same performance scaling settings are shared between multiple CPUs. Finally, some interfaces that aren't necessary any more are dropped from the generic power domains framework. On top of the above we have some minor extensions, cleanups and bug fixes in multiple places, as usual. Specifics: - ACPICA update to upstream revision 20150930 (Bob Moore, Lv Zheng). The most significant change is to allow the AML debugger to be built into the kernel. On top of that there is an update related to the NFIT table (the ACPI persistent memory interface) and a few fixes and cleanups. - ACPI CPPC2 (Collaborative Processor Performance Control v2) support along with a cpufreq frontend (Ashwin Chaugule). This can only be enabled on ARM64 at this point. - New ACPI infrastructure for the early probing of IRQ chips and clock sources (Marc Zyngier). - Support for a new hierarchical properties extension of the ACPI _DSD (Device Specific Data) device configuration object allowing the kernel to handle hierarchical properties (provided by the platform firmware this way) automatically and make them available to device drivers via the generic device properties interface (Rafael Wysocki). - Generic device properties API extension to obtain an index of certain string value in an array of strings, along the lines of of_property_match_string(), but working for all of the supported firmware node types, and support for the "dma-names" device property based on it (Mika Westerberg). - ACPI core fix to parse the MADT (Multiple APIC Description Table) entries in the order expected by platform firmware (and mandated by the specification) to avoid confusion on systems with more than 255 logical CPUs (Lukasz Anaczkowski). - Consolidation of the ACPI-based handling of PCI host bridges on x86 and ia64 (Jiang Liu). - ACPI core fixes to ensure that the correct IRQ number is used to represent the SCI (System Control Interrupt) in the cases when it has been re-mapped (Chen Yu). - New ACPI backlight quirk for Lenovo IdeaPad S405 (Hans de Goede). - ACPI EC driver fixes (Lv Zheng). - Assorted ACPI fixes and cleanups (Dan Carpenter, Insu Yun, Jiri Kosina, Rami Rosen, Rasmus Villemoes). - New mechanism in the PM core allowing drivers to check if the platform firmware is going to be involved in the upcoming system suspend or if it has been involved in the suspend the system is resuming from at the moment (Rafael Wysocki). This should allow drivers to optimize their suspend/resume handling in some cases and the changes include a couple of users of it (the i8042 input driver, PCI PM). - PCI PM fix to prevent runtime-suspended devices with PME enabled from being resumed during system suspend even if they aren't configured to wake up the system from sleep (Rafael Wysocki). - New mechanism to report the number of a wakeup IRQ that woke up the system from sleep last time (Alexandra Yates). - Removal of unused interfaces from the generic power domains framework and fixes related to latency measurements in that code (Ulf Hansson, Daniel Lezcano). - cpufreq core sysfs interface rework to make it handle CPUs that share performance scaling settings (represented by a common cpufreq policy object) more symmetrically (Viresh Kumar). This should help to simplify the CPU offline/online handling among other things. - cpufreq core fixes and cleanups (Viresh Kumar). - intel_pstate fixes related to the Turbo Activation Ratio (TAR) mechanism on client platforms which causes the turbo P-states range to vary depending on platform firmware settings (Srinivas Pandruvada). - intel_pstate sysfs interface fix (Prarit Bhargava). - Assorted cpufreq driver (imx, tegra20, powernv, integrator) fixes and cleanups (Bai Ping, Bartlomiej Zolnierkiewicz, Shilpasri G Bhat, Luis de Bethencourt). - cpuidle mvebu driver cleanups (Russell King). - OPP (Operating Performance Points) framework code reorganization to make it more maintainable (Viresh Kumar). - Intel Broxton support for the RAPL (Running Average Power Limits) power capping driver (Amy Wiles). - Assorted power management code fixes and cleanups (Dan Carpenter, Geert Uytterhoeven, Geliang Tang, Luis de Bethencourt, Rasmus Villemoes)" * tag 'pm+acpi-4.4-rc1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (108 commits) cpufreq: postfix policy directory with the first CPU in related_cpus cpufreq: create cpu/cpufreq/policyX directories cpufreq: remove cpufreq_sysfs_{create|remove}_file() cpufreq: create cpu/cpufreq at boot time cpufreq: Use cpumask_copy instead of cpumask_or to copy a mask cpufreq: ondemand: Drop unnecessary locks from update_sampling_rate() PM / Domains: Merge measurements for PM QoS device latencies PM / Domains: Don't measure ->start|stop() latency in system PM callbacks PM / clk: Fix broken build due to non-matching code and header #ifdefs ACPI / Documentation: add copy_dsdt to ACPI format options ACPI / sysfs: correctly check failing memory allocation ACPI / video: Add a quirk to force native backlight on Lenovo IdeaPad S405 ACPI / CPPC: Fix potential memory leak ACPI / CPPC: signedness bug in register_pcc_channel() ACPI / PAD: power_saving_thread() is not freezable ACPI / PM: Fix incorrect wakeup IRQ setting during suspend-to-idle ACPI: Using correct irq when waiting for events ACPI: Use correct IRQ when uninstalling ACPI interrupt handler cpuidle: mvebu: disable the bind/unbind attributes and use builtin_platform_driver cpuidle: mvebu: clean up multiple platform drivers ...
2015-09-24gpio: Introduce gpio descriptor 'name'Markus Pargmann
The latest gpio hogging mechanism assigns each gpio a 'line-name' in the devicetree. The 'name' field is different from the 'label' field. 'label' is only used for requested GPIOs to describe its current use by driver or userspace. The 'name' field describes the GPIO itself, not the use. This is most likely identical to the label in the schematic on the GPIO line and should help to find this particular GPIO. This is equivalent to the gpiochip->names array. However names should be stored in the GPIO descriptor. We will use gpiochip->names in the future only as initializer for the GPIO descriptors for drivers that assign GPIO names hardcoded. All other GPIO names will be parsed from DT and directly assigned to the GPIO descriptor. This patch adds a helper function to find gpio descriptors by name instead of gpio number. Signed-off-by: Markus Pargmann <mpa@pengutronix.de> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-09-15ACPI / property: Extend device_get_next_child_node() to data-only nodesRafael J. Wysocki
Make device_get_next_child_node() work with ACPI data-only subnodes introduced previously. Namely, replace acpi_get_next_child() with acpi_get_next_subnode() that can handle (and return) child device objects as well as child data-only subnodes of the given device and modify the ACPI part of the GPIO subsystem to handle data-only subnodes returned by it. To that end, introduce acpi_node_get_gpiod() taking a struct fwnode_handle pointer as the first argument. That argument may point to an ACPI device object as well as to a data-only subnode and the function should do the right thing (ie. look for the matching GPIO descriptor correctly) in either case. Next, modify fwnode_get_named_gpiod() to use acpi_node_get_gpiod() instead of acpi_get_gpiod_by_index() which automatically causes devm_get_gpiod_from_child() to work with ACPI data-only subnodes that may be returned by device_get_next_child_node() which in turn is required by the users of that function (the gpio_keys_polled and gpio-leds drivers). Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com> Acked-by: Linus Walleij <linus.walleij@linaro.org>
2015-05-12gpio: sysfs: move irq trigger flags to class-device dataJohan Hovold
Move irq trigger flags, which as sysfs-interface specific, to the class device data. This avoids accessing the gpio-descriptor flags field using non-atomic operations without any locking, and allows for a more clear separation of the sysfs interface from gpiolib core. Signed-off-by: Johan Hovold <johan@kernel.org> Reviewed-by: Alexandre Courbot <acourbot@nvidia.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-05-12gpio: sysfs: remove FLAG_SYSFS_DIRJohan Hovold
Remove FLAG_SYSFS_DIR, which is sysfs-interface specific, and store it in the class-device data instead. Note that the flag is only used during export. Signed-off-by: Johan Hovold <johan@kernel.org> Reviewed-by: Alexandre Courbot <acourbot@nvidia.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-05-12gpio: sysfs: clean up interrupt-interface implementationJohan Hovold
Store the value sysfs entry in the gpiod data rather than in a global table accessed through an index stored in the overloaded gpio-descriptor flag field. Signed-off-by: Johan Hovold <johan@kernel.org> Reviewed-by: Alexandre Courbot <acourbot@nvidia.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-05-12gpio: sysfs: rename gpiochip registration functionsJohan Hovold
Rename the gpio-chip export/unexport functions to the more descriptive names gpiochip_sysfs_register and gpiochip_sysfs_unregister. 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 'gpio-v4.1-1' 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 GPIO changes for the v4.1 development cycle: - A new GPIO hogging mechanism has been added. This can be used on boards that want to drive some GPIO line high, low, or set it as input on boot and then never touch it again. For some embedded systems this is bliss and simplifies things to a great extent. - Some API cleanup and closure: gpiod_get_array() and gpiod_put_array() has been added to get and put GPIOs in bulk as was possible with the non-descriptor API. - Encapsulate cross-calls to the pin control subsystem in <linux/gpio/driver.h>. Now this should be the only header any GPIO driver needs to include or something is wrong. Cleanups restricting drivers to this include are welcomed if tested. - Sort the GPIO Kconfig and split it into submenus, as it was becoming and unstructured, illogical and unnavigatable mess. I hope this is easier to follow. Menus that require a certain subsystem like I2C can now be hidden nicely for example, still working on others. - New drivers: - New driver for the Altera Soft GPIO. - The F7188x driver now handles the F71869 and F71869A variants. - The MIPS Loongson driver has been moved to drivers/gpio for consolidation and cleanup. - Cleanups: - The MAX732x is converted to use the GPIOLIB_IRQCHIP infrastructure. - The PCF857x is converted to use the GPIOLIB_IRQCHIP infrastructure. - Radical cleanup of the OMAP driver. - Misc: - Enable the DWAPB GPIO for all architectures. This is a "hard IP" block from Synopsys which has started to turn up in so diverse architectures as X86 Quark, ARC and a slew of ARM systems. So even though it's not an expander, it's generic enough to be available for all. - We add a mock GPIO on Crystalcove PMIC after a long discussion with Daniel Vetter et al, tracing back to the shootout at the kernel summit where DRM drivers and sub-componentization was discussed. In this case a mock GPIO is assumed to be the best compromise gaining some reuse of infrastructure without making DRM drivers overly complex at the same time. Let's see" * tag 'gpio-v4.1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (62 commits) Revert "gpio: sch: use uapi/linux/pci_ids.h directly" gpio: dwapb: remove dependencies gpio: dwapb: enable for ARC gpio: removing kfree remove functionality gpio: mvebu: Fix mask/unmask managment per irq chip type gpio: split GPIO drivers in submenus gpio: move MFD GPIO drivers under their own comment gpio: move BCM Kona Kconfig option gpio: arrange SPI Kconfig symbols alphabetically gpio: arrange PCI GPIO controllers alphabetically gpio: arrange I2C Kconfig symbols alphabetically gpio: arrange Kconfig symbols alphabetically gpio: ich: Implement get_direction function gpio: use (!foo) instead of (foo == NULL) gpio: arizona: drop owner assignment from platform_drivers gpio: max7300: remove 'ret' variable gpio: use devm_kzalloc gpio: sch: use uapi/linux/pci_ids.h directly gpio: x-gene: fix devm_ioremap_resource() check gpio: loongson: Add Loongson-3A/3B GPIO driver support ...
2015-03-16driver core / ACPI: Represent ACPI companions using fwnode_handleRafael J. Wysocki
Now that we have struct fwnode_handle, we can use that to point to ACPI companions from struct device objects instead of pointing to struct acpi_device directly. There are two benefits from that. First, the somewhat ugly and hackish struct acpi_dev_node can be dropped and, second, the same struct fwnode_handle pointer can be used in the future to point to other (non-ACPI) firmware device node types. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: Grant Likely <grant.likely@linaro.org>
2015-03-05gpiolib: add gpiod_get_array and gpiod_put_array functionsRojhalat Ibrahim
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>
2015-03-05gpiolib: define gpio suffixes globallyRojhalat Ibrahim
Avoid multiple identical definitions of the gpio suffix strings by putting them into a global constant array. Signed-off-by: Rojhalat Ibrahim <imr@rtschenk.de> Reviewed-by: Alexandre Courbot <acourbot@nvidia.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-03-04gpio: add GPIO hogging mechanismBenoit Parrot
Based on Boris Brezillion's work this is a reworked patch of his initial GPIO hogging mechanism. This patch provides a way to initially configure specific GPIO when the GPIO controller is probed. The actual DT scanning to collect the GPIO specific data is performed as part of gpiochip_add(). The purpose of this is to allow specific GPIOs to be configured without any driver specific code. This is particularly useful because board design are getting increasingly complex and given SoC pins can now have more than 10 mux values, a lot of connections are now dependent on external IO muxes to switch various modes. Specific drivers should not necessarily need to be aware of what accounts to a specific board implementation. This board level "description" should be best kept as part of the dts file. Signed-off-by: Benoit Parrot <bparrot@ti.com> Reviewed-by: Alexandre Courbot <acourbot@nvidia.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-01-15gpio: sysfs: fix gpio attribute-creation raceJohan Hovold
Fix attribute-creation race with userspace by using the default group to create also the contingent gpio device attributes. Fixes: d8f388d8dc8d ("gpio: sysfs interface") Signed-off-by: Johan Hovold <johan@kernel.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-11-04gpio / ACPI: Add support for _DSD device propertiesMika Westerberg
With release of ACPI 5.1 and _DSD method we can finally name GPIOs (and other things as well) returned by _CRS. Previously we were only able to use integer index to find the corresponding GPIO, which is pretty error prone if the order changes. With _DSD we can now query GPIOs using name instead of an integer index, like the below example shows: // Bluetooth device with reset and shutdown GPIOs Device (BTH) { Name (_HID, ...) Name (_CRS, ResourceTemplate () { GpioIo (Exclusive, PullUp, 0, 0, IoRestrictionInputOnly, "\\_SB.GPO0", 0, ResourceConsumer) {15} GpioIo (Exclusive, PullUp, 0, 0, IoRestrictionInputOnly, "\\_SB.GPO0", 0, ResourceConsumer) {27, 31} }) Name (_DSD, Package () { ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"), Package () { Package () {"reset-gpio", Package() {^BTH, 1, 1, 0 }}, Package () {"shutdown-gpio", Package() {^BTH, 0, 0, 0 }}, } }) } The format of the supported GPIO property is: Package () { "name", Package () { ref, index, pin, active_low }} ref - The device that has _CRS containing GpioIo()/GpioInt() resources, typically this is the device itself (BTH in our case). index - Index of the GpioIo()/GpioInt() resource in _CRS starting from zero. pin - Pin in the GpioIo()/GpioInt() resource. Typically this is zero. active_low - If 1 the GPIO is marked as active_low. Since ACPI GpioIo() resource does not have field saying whether it is active low or high, the "active_low" argument can be used here. Setting it to 1 marks the GPIO as active low. In our Bluetooth example the "reset-gpio" refers to the second GpioIo() resource, second pin in that resource with the GPIO number of 31. This patch implements necessary support to gpiolib for extracting GPIOs using _DSD device properties. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Acked-by: Linus Walleij <linus.walleij@linaro.org> Acked-by: Grant Likely <grant.likely@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-07-28gpio / ACPI: Move event handling registration to gpiolib irqchip helpersMika Westerberg
Since now we have irqchip helpers that the GPIO chip drivers are supposed to use if possible, we can move the registration of ACPI events to happen in these helpers. This seems to be more natural place and might encourage GPIO chip driver writers to take advantage of the irqchip helpers. We make the functions available to GPIO chip drivers via private gpiolib.h, just in case generic irqchip helpers are not suitable. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-07-24gpiolib: Export gpiochip_request_own_desc and gpiochip_free_own_descGuenter Roeck
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: make gpiochip_get_desc() gpiolib-privateAlexandre Courbot
As GPIO descriptors are not going to remain unique anymore, having this function public is not safe. Restrain its use to gpiolib since we have no user outside of it. Signed-off-by: Alexandre Courbot <acourbot@nvidia.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-07-09gpio: move sysfs support to its own fileAlexandre Courbot
sysfs support is currently entangled within the core GPIO support, while it should relly just be a (privileged) user of the integer GPIO API. This patch is a first step towards making the gpiolib code more readable by splitting it into logical parts. Move all sysfs support to their own source file, and share static members of gpiolib that need to be in the private gpiolib.h file. In the future we will want to put some of them back into gpiolib.c, but this first patch let us at least identify them. Signed-off-by: Alexandre Courbot <acourbot@nvidia.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-05-21gpio: make of_get_named_gpiod_flags() privateAlexandre Courbot
of_get_named_gpiod_flags() is visible and directly usable by GPIO consumers, but it really should not as the gpiod interface relies on the simpler gpiod_get() to provide properly-configured GPIOs. of_get_named_gpiod_flags() is just used internally by gpiolib to implement gpiod_get(), and by the old of_get_named_gpio_flags() function, therefore it makes sense to make it gpiolib-private. As a side-effect, the unused (and unneeded) of_get_gpiod_flags() inline function is also removed, and of_get_named_gpio_flags() is moved from a static inline function to a regular one in gpiolib-of.c This results in all references to gpiod_* functions in of_gpio.h being gone, which is the way it should be since this file is part of the old integer GPIO interface. Changes since v1: - Fixed compilation error when CONFIG_OF_GPIO is not defined - Fixed warning due to of_gpio_flags enum not being declared in private gpiolib.h header Signed-off-by: Alexandre Courbot <acourbot@nvidia.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-03-13gpiolib: Allow GPIO chips to request their own GPIOsMika Westerberg
Sometimes it is useful to allow GPIO chips themselves to request GPIOs they own through gpiolib API. One use case is ACPI ASL code that should be able to toggle GPIOs through GPIO operation regions. We can't use gpio_request() because it will pin the module to the kernel forever (it calls try_module_get()). To solve this we move module refcount manipulation to gpiod_request() and let __gpiod_request() handle the actual request. This changes the sequence a bit as now try_module_get() is called outside of gpio_lock (I think this is safe, try_module_get() handles serialization it needs already). Then we provide gpiolib internal functions gpiochip_request/free_own_desc() that do the same as gpio_request() but don't manipulate module refrence count. This allows the GPIO chip driver to request and free descriptors it owns without being pinned to the kernel forever. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Reviewed-by: Alexandre Courbot <acourbot@nvidia.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-01-08gpio / ACPI: get rid of acpi_gpio.hMika Westerberg
Now that all users of acpi_gpio.h have been moved to use either the GPIO descriptor interface or to the internal gpiolib.h we can get rid of acpi_gpio.h entirely. Once this is done the only interface to get GPIOs to drivers enumerated from ACPI namespace is the descriptor based interface. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Alexandre Courbot <acourbot@nvidia.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-01-08gpio / ACPI: register to ACPI events automaticallyMika Westerberg
Instead of asking each driver to register to ACPI events we can just call acpi_gpiochip_register_interrupts() for each chip that has an ACPI handle. The function checks chip->to_irq and if it is set to NULL (a GPIO driver that doesn't do interrupts) the function does nothing. We also add the a new header drivers/gpio/gpiolib.h that is used for functions internal to gpiolib and add ACPI GPIO chip registering functions to that header. Once that is done we can remove call to acpi_gpiochip_register_interrupts() from its only user, pinctrl-baytrail.c Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>