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path: root/drivers/gpio/gpiolib.c
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2019-02-13gpio: add core support for pull-up/pull-down configurationThomas Petazzoni
This commit adds support for configuring the pull-up and pull-down resistors available in some GPIO controllers. While configuring pull-up/pull-down is already possible through the pinctrl subsystem, some GPIO controllers, especially simple ones such as GPIO expanders on I2C, don't have any pinmuxing capability and therefore do not use the pinctrl subsystem. This commit implements the GPIO_PULL_UP and GPIO_PULL_DOWN flags, which can be used from the Device Tree, to enable a pull-up or pull-down resistor on a given GPIO. The flag is simply propagated all the way to the core GPIO subsystem, where it is used to call the gpio_chip ->set_config callback with the appropriate existing PIN_CONFIG_BIAS_* values. Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2019-02-13gpio: use new gpio_set_config() helper in more placesThomas Petazzoni
As suggested by Linus Walleij, let's use the new gpio_set_config() helper in gpiod_set_debounce() and gpiod_set_transitory(). Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2019-02-13gpio: rename gpio_set_drive_single_ended() to gpio_set_config()Thomas Petazzoni
This commit simply renames gpio_set_drive_single_ended() to gpio_set_config(), as the function is not specific to setting the GPIO drive type, and will be used for other purposes in followup commits. In addition, it moves the function above gpiod_direction_input(), as it will be used from gpiod_direction_input(). Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2019-01-24gpio: add irq domain activate/deactivate functionsBrian Masney
This adds the two new functions gpiochip_irq_domain_activate and gpiochip_irq_domain_deactivate that can be used as the activate and deactivate functions in the struct irq_domain_ops. This is for situations where only gpiochip_{lock,unlock}_as_irq needs to be called. SPMI and SSBI GPIO are two users that will initially use these functions. Signed-off-by: Brian Masney <masneyb@onstation.org> Suggested-by: Stephen Boyd <sboyd@kernel.org> Reviewed-by: Stephen Boyd <sboyd@kernel.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2019-01-23gpiolib: fix line event timestamps for nested irqsBartosz Golaszewski
Nested interrupts run inside the calling thread's context and the top half handler is never called which means that we never read the timestamp. This issue came up when trying to read line events from a gpiochip using regmap_irq_chip for interrupts. Fix it by reading the timestamp from the irq thread function if it's still 0 by the time the second handler is called. Fixes: d58f2bf261fd ("gpio: Timestamp events in hardirq handler") Cc: stable@vger.kernel.org Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
2018-12-28Merge tag 'gpio-v4.21-1' 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 v4.21 kernel series. Core changes: - Some core changes are already in outside of this pull request as they came through the regulator tree, most notably devm_gpiod_unhinge() that removes devres refcount management from a GPIO descriptor. This is needed in subsystems such as regulators where the regulator core need to take over the reference counting and lifecycle management for a GPIO descriptor. - We dropped devm_gpiochip_remove() and devm_gpio_chip_match() as nothing needs it. We can bring it back if need be. - Add a global TODO so people see where we are going. This helps setting the direction now that we are two GPIO maintainers. - Handle the MMC CD/WP properties in the device tree core. (The bulk of patches activating this code is already merged through the MMC/SD tree.) - Augment gpiochip_request_own_desc() to pass a flag so we as gpiochips can request lines as active low or open drain etc even from ourselves. New drivers: - New driver for Cadence GPIO blocks. - New driver for Atmel SAMA5D2 PIOBU GPIO lines. Driver improvements: - A major refactoring of the PCA953x driver - this driver has been around for ages, and is now modernized to reduce code duplication that has stacked up and is using regmap to read write and cache registers. - Intel drivers are now maintained in a separate tree and start with a round of cleanups and unifications" * tag 'gpio-v4.21-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (99 commits) gpio: sama5d2-piobu: Depend on OF_GPIO gpio: Add Cadence GPIO driver dt-bindings: gpio: Add bindings for Cadence GPIO gpiolib-acpi: remove unused variable 'err', cleans up build warning gpio: mxs: read pin level directly instead of using .get gpio: aspeed: remove duplicated statement gpio: add driver for SAMA5D2 PIOBU pins dt-bindings: arm: atmel: describe SECUMOD usage as a GPIO controller gpio/mmc/of: Respect polarity in the device tree dt-bindings: gpio: rcar: Add r8a774c0 (RZ/G2E) support memory: omap-gpmc: Get the header of the enum ARM: omap1: Fix new user of gpiochip_request_own_desc() gpio: pca953x: Add regmap dependency for PCA953x driver gpio: raspberrypi-exp: decrease refcount on firmware dt node gpiolib: Fix return value of gpio_to_desc() stub if !GPIOLIB gpio: pca953x: Restore registers after suspend/resume cycle gpio: pca953x: Zap single use of pca953x_read_single() gpio: pca953x: Zap ad-hoc reg_output cache gpio: pca953x: Zap ad-hoc reg_direction cache gpio: pca953x: Perform basic regmap conversion ...
2018-12-14gpio: Pass a flag to gpiochip_request_own_desc()Linus Walleij
Before things go out of hand, make it possible to pass flags when requesting "own" descriptors from a gpio_chip. This is necessary if the chip wants to request a GPIO with active low semantics, for example. Cc: Janusz Krzysztofik <jmkrzyszt@gmail.com> Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com> Cc: Jason Cooper <jason@lakedaemon.net> Cc: Jiri Kosina <jkosina@suse.cz> Cc: Roger Quadros <rogerq@ti.com> Reviewed-by: Gregory CLEMENT <gregory.clement@free-electrons.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-12-11Merge branch 'for-linus' of ↵Mark Brown
https://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator into regulator-4.21
2018-12-11gpio: Enable nonexclusive gpiods from DT nodesLinus Walleij
This makes gpiod_get_from_of_node() respect the GPIOD_FLAGS_BIT_NONEXCLUSIVE flag which is especially nice when getting regulator GPIOs right out of device tree nodes. Suggested-by: Marek Szyprowski <m.szyprowski@samsung.com> Fixes: b0ce7b29bfcd ("regulator/gpio: Allow nonexclusive GPIO access") Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Reviewed-by: Marek Szyprowski <m.szyprowski@samsung.com> Tested-by: Marek Szyprowski <m.szyprowski@samsung.com> Reviewed-by: Charles Keepax <ckeepax@opensource.cirrus.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2018-11-15gpio: drop devm_gpio_chip_match()Laurent Pinchart
Commit 48207d7595d2 ("gpio: drop devm_gpiochip_remove()") dropped the last user of drop devm_gpio_chip_match(), causing a defined but not used compilation warning. Fix it by removing the function. Fixes: 48207d7595d2 ("gpio: drop devm_gpiochip_remove()") Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com> Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Acked-by: Olof Johansson <olof@lixom.net> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-11-09gpio: don't free unallocated ida on gpiochip_add_data_with_key() error pathVladimir Zapolskiy
The change corrects the error path in gpiochip_add_data_with_key() by avoiding to call ida_simple_remove(), if ida_simple_get() returns an error. Note that ida_simple_remove()/ida_free() throws a BUG(), if id argument is negative, it allows to easily check the correctness of the fix by fuzzing the return value from ida_simple_get(). Fixes: ff2b13592299 ("gpio: make the gpiochip a real device") Cc: stable@vger.kernel.org # v4.6+ Signed-off-by: Vladimir Zapolskiy <vz@mleia.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-11-05gpiolib: Fix possible use after free on labelMuchun Song
gpiod_request_commit() copies the pointer to the label passed as an argument only to be used later. But there's a chance the caller could immediately free the passed string(e.g., local variable). This could trigger a use after free when we use gpio label(e.g., gpiochip_unlock_as_irq(), gpiochip_is_requested()). To be on the safe side: duplicate the string with kstrdup_const() so that if an unaware user passes an address to a stack-allocated buffer, we won't get the arbitrary label. Also fix gpiod_set_consumer_name(). Signed-off-by: Muchun Song <smuchun@gmail.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-11-05gpio: drop devm_gpiochip_remove()Uwe Kleine-König
There is hardly any reason to call devm_gpiochip_remove() because the driver core handles calling gpiochip_remove() automatically. To make it harder to introduce new (and probably unneeded) callers, drop the function. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-10-23Merge tag 'gpio-v4.20-1' 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 v4.20 series: Core changes: - A patch series from Hans Verkuil to make it possible to enable/disable IRQs on a GPIO line at runtime and drive GPIO lines as output without having to put/get them from scratch. The irqchip callbacks have been improved so that they can use only the fastpatch callbacks to enable/disable irqs like any normal irqchip, especially the gpiod_lock_as_irq() has been improved to be callable in fastpath context. A bunch of rework had to be done to achieve this but it is a big win since I never liked to restrict this to slowpath. The only call requireing slowpath was try_module_get() and this is kept at the .request_resources() slowpath callback. In the GPIO CEC driver this is a big win sine a single line is used for both outgoing and incoming traffic, and this needs to use IRQs for incoming traffic while actively driving the line for outgoing traffic. - Janusz Krzysztofik improved the GPIO array API to pass a "cookie" (struct gpio_array) and a bitmap for setting or getting multiple GPIO lines at once. This improvement orginated in a specific need to speed up an OMAP1 driver and has led to a much better API and real performance gains when the state of the array can be used to bypass a lot of checks and code when we want things to go really fast. The previous code would minimize the number of calls down to the driver callbacks assuming the CPU speed was orders of magnitude faster than the I/O latency, but this assumption was wrong on several platforms: what we needed to do was to profile and improve the speed on the hot path of the array functions and this change is now completed. - Clean out the painful and hard to grasp BNF experiments from the device tree bindings. Future approaches are looking into using JSON schema for this purpose. (Rob Herring is floating a patch series.) New drivers: - The RCAR driver now supports r8a774a1 (RZ/G2M). - Synopsys GPIO via CREGs driver. Major improvements: - Modernization of the EP93xx driver to use irqdomain and other contemporary concepts. - The ingenic driver has been merged into the Ingenic pin control driver and removed from the GPIO subsystem. - Debounce support in the ftgpio010 driver" * tag 'gpio-v4.20-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (116 commits) gpio: Clarify kerneldoc on gpiochip_set_chained_irqchip() gpio: Remove unused 'irqchip' argument to gpiochip_set_cascaded_irqchip() gpio: Drop parent irq assignment during cascade setup mmc: pwrseq_simple: Fix incorrect handling of GPIO bitmap gpio: fix SNPS_CREG kconfig dependency warning gpiolib: Initialize gdev field before is used gpio: fix kernel-doc after devres.c file rename gpio: fix doc string for devm_gpiochip_add_data() to not talk about irq_chip gpio: syscon: Fix possible NULL ptr usage gpiolib: Show correct direction from the beginning pinctrl: msm: Use init_valid_mask exported function gpiolib: Add init_valid_mask exported function GPIO: add single-register GPIO via CREG driver dt-bindings: Document the Synopsys GPIO via CREG bindings gpio: mockup: use device properties instead of platform_data gpio: Slightly more helpful debugfs gpio: omap: Remove set but not used variable 'dev' gpio: omap: drop omap_gpio_list Accept partial 'gpio-line-names' property. gpio: omap: get rid of the conditional PM runtime calls ...
2018-10-21Merge branch 'regulator-4.20' into regulator-nextMark Brown
2018-10-16gpio: Clarify kerneldoc on gpiochip_set_chained_irqchip()Stephen Boyd
This doesn't support nested anymore, so drivers shouldn't call it with the handler set to NULL. Cc: Evan Green <evgreen@chromium.org> Cc: Thierry Reding <treding@nvidia.com> Cc: Grygorii Strashko <grygorii.strashko@ti.com> Signed-off-by: Stephen Boyd <swboyd@chromium.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-10-16gpio: Remove unused 'irqchip' argument to gpiochip_set_cascaded_irqchip()Stephen Boyd
This argument hasn't ever been used since it was introduced in commit 1425052097b5 ("gpio: add IRQ chip helpers in gpiolib"). Let's drop it to reduce reading confusion. Cc: Evan Green <evgreen@chromium.org> Cc: Thierry Reding <treding@nvidia.com> Cc: Grygorii Strashko <grygorii.strashko@ti.com> Signed-off-by: Stephen Boyd <swboyd@chromium.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-10-16gpio: Drop parent irq assignment during cascade setupStephen Boyd
We want to set the irq parent for interrupts that we're setting up to be cascaded from another interrupt controller, but we may or may not have already mapped the gpiochip irqs into the kernel's virtual irq number space at this point. If we have mapped irqs before calling here, then we've gone through gpiochip_irq_map() and called irq_set_parent() already. If we haven't mapped irqs, then the gpiochip is dynamically mapping irqs and we can rely on gpiochip_irq_map() or the gpio driver's irqdomain ops to setup the irq parent properly. Either way, setting the parent here when cascading the gpiochip doesn't make much sense because it should be done at irq mapping time. In the dynamic mapping case, this code is mapping virq 0 to some parent virq in a loop. While that's benign, let's drop this code to simplify. Cc: Evan Green <evgreen@chromium.org> Cc: Thierry Reding <treding@nvidia.com> Cc: Grygorii Strashko <grygorii.strashko@ti.com> Signed-off-by: Stephen Boyd <swboyd@chromium.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-10-12regulator/gpio: Allow nonexclusive GPIO accessLinus Walleij
This allows nonexclusive (simultaneous) access to a single GPIO line for the fixed regulator enable line. This happens when several regulators use the same GPIO for enabling and disabling a regulator, and all need a handle on their GPIO descriptor. This solution with a special flag is not entirely elegant and should ideally be replaced by something more careful as this makes it possible for several consumers to enable/disable the same GPIO line to the left and right without any consistency. The current use inside the regulator core should however be fine as it takes special care to handle this. For the state of the GPIO backend, this is still the lesser evil compared to going back to global GPIO numbers. Cc: Marek Szyprowski <m.szyprowski@samsung.com> Cc: Jon Hunter <jonathanh@nvidia.com> Fixes: efdfeb079cc3 ("regulator: fixed: Convert to use GPIO descriptor only") Reported-by: Marek Szyprowski <m.szyprowski@samsung.com> Tested-by: Jon Hunter <jonathanh@nvidia.com> Tested-by: Marek Szyprowski <m.szyprowski@samsung.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Mark Brown <broonie@kernel.org>
2018-10-12gpiolib: Initialize gdev field before is usedRicardo Ribalda Delgado
gpio_hog depends on gdev field being initialized. This patch fixes an OOPs during initialization of TI's AM335x-ICEv2. Fixes: 3edfb7bd76bd1cba ("gpiolib: Show correct direction from the beginning") Tested-by: Vignesh R <vigneshr@ti.com> Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-10-10gpio: Assign gpio_irq_chip::parents to non-stack pointerStephen Boyd
gpiochip_set_cascaded_irqchip() is passed 'parent_irq' as an argument and then the address of that argument is assigned to the gpio chips gpio_irq_chip 'parents' pointer shortly thereafter. This can't ever work, because we've just assigned some stack address to a pointer that we plan to dereference later in gpiochip_irq_map(). I ran into this issue with the KASAN report below when gpiochip_irq_map() tried to setup the parent irq with a total junk pointer for the 'parents' array. BUG: KASAN: stack-out-of-bounds in gpiochip_irq_map+0x228/0x248 Read of size 4 at addr ffffffc0dde472e0 by task swapper/0/1 CPU: 7 PID: 1 Comm: swapper/0 Not tainted 4.14.72 #34 Call trace: [<ffffff9008093638>] dump_backtrace+0x0/0x718 [<ffffff9008093da4>] show_stack+0x20/0x2c [<ffffff90096b9224>] __dump_stack+0x20/0x28 [<ffffff90096b91c8>] dump_stack+0x80/0xbc [<ffffff900845a350>] print_address_description+0x70/0x238 [<ffffff900845a8e4>] kasan_report+0x1cc/0x260 [<ffffff900845aa14>] __asan_report_load4_noabort+0x2c/0x38 [<ffffff900897e098>] gpiochip_irq_map+0x228/0x248 [<ffffff900820cc08>] irq_domain_associate+0x114/0x2ec [<ffffff900820d13c>] irq_create_mapping+0x120/0x234 [<ffffff900820da78>] irq_create_fwspec_mapping+0x4c8/0x88c [<ffffff900820e2d8>] irq_create_of_mapping+0x180/0x210 [<ffffff900917114c>] of_irq_get+0x138/0x198 [<ffffff9008dc70ac>] spi_drv_probe+0x94/0x178 [<ffffff9008ca5168>] driver_probe_device+0x51c/0x824 [<ffffff9008ca6538>] __device_attach_driver+0x148/0x20c [<ffffff9008ca14cc>] bus_for_each_drv+0x120/0x188 [<ffffff9008ca570c>] __device_attach+0x19c/0x2dc [<ffffff9008ca586c>] device_initial_probe+0x20/0x2c [<ffffff9008ca18bc>] bus_probe_device+0x80/0x154 [<ffffff9008c9b9b4>] device_add+0x9b8/0xbdc [<ffffff9008dc7640>] spi_add_device+0x1b8/0x380 [<ffffff9008dcbaf0>] spi_register_controller+0x111c/0x1378 [<ffffff9008dd6b10>] spi_geni_probe+0x4dc/0x6f8 [<ffffff9008cab058>] platform_drv_probe+0xdc/0x130 [<ffffff9008ca5168>] driver_probe_device+0x51c/0x824 [<ffffff9008ca59cc>] __driver_attach+0x100/0x194 [<ffffff9008ca0ea8>] bus_for_each_dev+0x104/0x16c [<ffffff9008ca58c0>] driver_attach+0x48/0x54 [<ffffff9008ca1edc>] bus_add_driver+0x274/0x498 [<ffffff9008ca8448>] driver_register+0x1ac/0x230 [<ffffff9008caaf6c>] __platform_driver_register+0xcc/0xdc [<ffffff9009c4b33c>] spi_geni_driver_init+0x1c/0x24 [<ffffff9008084cb8>] do_one_initcall+0x240/0x3dc [<ffffff9009c017d0>] kernel_init_freeable+0x378/0x468 [<ffffff90096e8240>] kernel_init+0x14/0x110 [<ffffff9008086fcc>] ret_from_fork+0x10/0x18 The buggy address belongs to the page: page:ffffffbf037791c0 count:0 mapcount:0 mapping: (null) index:0x0 flags: 0x4000000000000000() raw: 4000000000000000 0000000000000000 0000000000000000 00000000ffffffff raw: ffffffbf037791e0 ffffffbf037791e0 0000000000000000 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffffffc0dde47180: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffffffc0dde47200: f1 f1 f1 f1 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f2 f2 >ffffffc0dde47280: f2 f2 00 00 00 00 00 00 00 00 00 00 f3 f3 f3 f3 ^ ffffffc0dde47300: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffffffc0dde47380: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 Let's leave around one unsigned int in the gpio_irq_chip struct for the single parent irq case and repoint the 'parents' array at it. This way code is left mostly intact to setup parents and we waste an extra few bytes per structure of which there should be only a handful in a system. Cc: Evan Green <evgreen@chromium.org> Cc: Thierry Reding <treding@nvidia.com> Cc: Grygorii Strashko <grygorii.strashko@ti.com> Fixes: e0d897289813 ("gpio: Implement tighter IRQ chip integration") Signed-off-by: Stephen Boyd <swboyd@chromium.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-10-10gpio: fix doc string for devm_gpiochip_add_data() to not talk about irq_chipUwe Kleine-König
The function is about adding a gpio_chip so dev has to belong to this one. Fix wording to be more grammatically correct (but attention, I'm not a native speaker). Signed-off-by: Uwe Kleine-König <uwe@kleine-koenig.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-10-10gpiolib: Show correct direction from the beginningRicardo Ribalda Delgado
Current code assumes that the direction is input if direction_input function is set. This might not be the case on GPIOs with programmable direction. Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com> Tested-by: Jeffrey Hugo <jhugo@codeaurora.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-10-10gpiolib: Add init_valid_mask exported functionRicardo Ribalda Delgado
Add a function that allows initializing the valid_mask from gpiochip_add_data. This prevents race conditions during gpiochip initialization. If the function is not exported, then the old behaviour is respected, this is, set all gpios as valid. Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com> Tested-by: Jeffrey Hugo <jhugo@codeaurora.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-10-02gpio: Slightly more helpful debugfsLinus Walleij
This at least makes debugfs print if the line is active high or low. That is pretty helpful as what we display as "lo" or "hi" is the raw physical level of the line. Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-10-01gpio: Restore indentation of continued linesGeert Uytterhoeven
Fixes: 3027743f83f867d8 ("gpio: Remove VLA from gpiolib") Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-10-01gpio: Propagate errors from gpiod_set_array_value_complex()Geert Uytterhoeven
Internal helper function gpiod_set_array_value_complex() was changed to return an error value, but not all gpiolib callers were updated to propagate the new error up. Fixes: 3027743f83f867d8 ("gpio: Remove VLA from gpiolib") Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-10-01gpiolib: Fix incorrect use of find_next_zero_bit()Janusz Krzysztofik
Commit b17566a6b08b ("gpiolib: Implement fast processing path in get/set array"), already fixed to some extent with commit 5d581d7e8cdc ("gpiolib: Fix missing updates of bitmap index"), introduced a new mode of processing bitmaps where bits applicable for fast bitmap processing path are supposed to be skipped while iterating bits which don't apply. Unfortunately, find_next_zero_bit() function supposed to skip over those fast bits is always called with a 'start' argument equal to an index of last zero bit found and returns that index value again an again, causing an infinite loop. Fix it by incrementing the index uncoditionally before find_next_zero_bit() is optionally called. Reported-by: Marek Szyprowski <m.szyprowski@samsung.com> Signed-off-by: Janusz Krzysztofik <jmkrzyszt@gmail.com> Tested-by: Marek Szyprowski <m.szyprowski@samsung.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-09-25gpio: Add comments on single direction chipsLinus Walleij
A patch from Ricardo got me thinking about some gpio chip semantics so let's drop in some comments to make things more clear around that. Cc: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com> Cc: Bartosz Golaszewski <brgl@bgdev.pl> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-09-25gpiolib: Fix gpio_direction_* for single direction GPIOsRicardo Ribalda Delgado
GPIOs with no programmable direction are not required to implement direction_output nor direction_input. If we try to set an output direction on an output-only GPIO or input direction on an input-only GPIO simply return 0. This allows this single direction GPIO to be used by libgpiod. Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-09-25gpio: Use SPDX header for core libraryLinus Walleij
Use the SPDX headers and cut down on boilerplate to indicate the license in the core gpiolib implementation. Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-09-24gpiolib: Fix array members of same chip processed separatelyJanusz Krzysztofik
New code introduced by commit bf9346f5d47b ("gpiolib: Identify arrays matching GPIO hardware") forcibly tries to find an array member which has its array index number equal to its hardware pin number and set up an array info for possible fast bitmap processing of all arrray pins belonging to that chip which also satisfy that numbering rule. Depending on array content, it may happen that consecutive array members which belong to the same chip but don't have array indexes equal to their pin hardware numbers will be split into groups, some of them processed together via the fast bitmap path, and rest of them separetely. However, applications may expect all those pins being processed together with a single call to .set_multiple() chip callback, like that was done before the change. Limit applicability of fast bitmap processing path to cases where all pins of consecutive array members starting from 0 which belong to the same chip have their hardware numbers equal to their corresponding array indexes. That should still speed up processing of applications using whole GPIO banks as I/O ports, while not breaking simultaneous manipulation of consecutive pins of the same chip which don't follow the equal numbering rule. Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Janusz Krzysztofik <jmkrzyszt@gmail.com> Tested-by: Marek Szyprowski <m.szyprowski@samsung.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-09-24gpiolib: Fix missing updates of bitmap indexJanusz Krzysztofik
In new code introduced by commit b17566a6b08b ("gpiolib: Implement fast processing path in get/set array"), bitmap index is not updated with next found zero bit position as it should while skipping over pins already processed via fast bitmap path, possibly resulting in an infinite loop. Fix it. Signed-off-by: Janusz Krzysztofik <jmkrzyszt@gmail.com> Tested-by: Marek Szyprowski <m.szyprowski@samsung.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-09-20Merge branch 'ib-array-bitmaps' into develLinus Walleij
2018-09-18gpiolib: Free the last requested descriptorRicardo Ribalda Delgado
The current code only frees N-1 gpios if an error occurs during gpiod_set_transitory, gpiod_direction_output or gpiod_direction_input. Leading to gpios that cannot be used by userspace nor other drivers. Cc: Timur Tabi <timur@codeaurora.org> Cc: stable@vger.kernel.org Fixes: ab3dbcf78f60f46d ("gpioib: do not free unrequested descriptors) Reported-by: Jan Lorenzen <jl@newtec.dk> Reported-by: Jim Paris <jim@jtan.com> Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-09-17gpiolib: check if irqchip already has the irq hook replacementsHans Verkuil
Some drivers use a single irqchip for multiple gpiochips. As a result the irqchip hooks are overridden for the first gpiochip that was added, but for the other gpiochip instances this should not happen again, otherwise we would go into an infinite recursion. Check for this, but also log a message that the driver should be fixed since this is bad practice. Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com> Tested-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-09-14gpiolib: use better errno if get_direction is not availableWolfram Sang
EINVAL is very generic, use ENOTSUPP in case the gpiochip does not provide this function. While removing the assignment from the 'status' variable, use better indentation in the declaration block. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Reviewed-by: Simon Horman <horms+renesas@verge.net.au> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-09-13gpiolib: Implement fast processing path in get/set arrayJanusz Krzysztofik
Certain GPIO descriptor arrays returned by gpio_get_array() may contain information on direct mapping of array members to pins of a single GPIO chip in hardware order. In such cases, bitmaps of values can be passed directly from/to the chip's .get/set_multiple() callbacks without wasting time on iterations. Add respective code to gpiod_get/set_array_bitmap_complex() functions. Pins not applicable for fast path are processed as before, skipping over the 'fast' ones. Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Janusz Krzysztofik <jmkrzyszt@gmail.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-09-13gpiolib: Pass array info to get/set array functionsJanusz Krzysztofik
In order to make use of array info obtained from gpiod_get_array() and speed up processing of arrays matching single GPIO chip layout, that information must be passed to get/set array functions. Extend the functions' API with that additional parameter and update all users. Pass NULL if a user builds an array itself from single GPIOs. Cc: Jonathan Corbet <corbet@lwn.net> Cc: Miguel Ojeda Sandonis <miguel.ojeda.sandonis@gmail.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Sebastien Bourdelin <sebastien.bourdelin@savoirfairelinux.com> Cc: Lukas Wunner <lukas@wunner.de> Cc: Peter Korsgaard <peter.korsgaard@barco.com> Cc: Peter Rosin <peda@axentia.se> Cc: Andrew Lunn <andrew@lunn.ch> Cc: Florian Fainelli <f.fainelli@gmail.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Rojhalat Ibrahim <imr@rtschenk.de> Cc: Dominik Brodowski <linux@dominikbrodowski.net> Cc: Russell King <rmk+kernel@armlinux.org.uk> Cc: Kishon Vijay Abraham I <kishon@ti.com> Cc: Tony Lindgren <tony@atomide.com> Cc: Lars-Peter Clausen <lars@metafoo.de> Cc: Michael Hennerich <Michael.Hennerich@analog.com> Cc: Jonathan Cameron <jic23@kernel.org> Cc: Hartmut Knaack <knaack.h@gmx.de> Cc: Peter Meerwald-Stadler <pmeerw@pmeerw.net> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jiri Slaby <jslaby@suse.com> Cc: Yegor Yefremov <yegorslists@googlemail.com> Cc: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Janusz Krzysztofik <jmkrzyszt@gmail.com> Acked-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-09-13gpiolib: Identify arrays matching GPIO hardwareJanusz Krzysztofik
Certain GPIO array lookup results may map directly to GPIO pins of a single GPIO chip in hardware order. If that condition is recognized and handled efficiently, significant performance gain of get/set array functions may be possible. While processing a request for an array of GPIO descriptors, identify those which represent corresponding pins of a single GPIO chip. Skip over pins which require open source or open drain special processing. Moreover, identify pins which require inversion. Pass a pointer to that information with the array to the caller so it can benefit from enhanced performance as soon as get/set array functions can accept and make efficient use of it. Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Janusz Krzysztofik <jmkrzyszt@gmail.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-09-13gpiolib: Pass bitmaps, not integer arrays, to get/set arrayJanusz Krzysztofik
Most users of get/set array functions iterate consecutive bits of data, usually a single integer, while processing array of results obtained from, or building an array of values to be passed to those functions. Save time wasted on those iterations by changing the functions' API to accept bitmaps. All current users are updated as well. More benefits from the change are expected as soon as planned support for accepting/passing those bitmaps directly from/to respective GPIO chip callbacks if applicable is implemented. Cc: Jonathan Corbet <corbet@lwn.net> Cc: Miguel Ojeda Sandonis <miguel.ojeda.sandonis@gmail.com> Cc: Sebastien Bourdelin <sebastien.bourdelin@savoirfairelinux.com> Cc: Lukas Wunner <lukas@wunner.de> Cc: Peter Korsgaard <peter.korsgaard@barco.com> Cc: Peter Rosin <peda@axentia.se> Cc: Andrew Lunn <andrew@lunn.ch> Cc: Florian Fainelli <f.fainelli@gmail.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Rojhalat Ibrahim <imr@rtschenk.de> Cc: Dominik Brodowski <linux@dominikbrodowski.net> Cc: Russell King <rmk+kernel@armlinux.org.uk> Cc: Kishon Vijay Abraham I <kishon@ti.com> Cc: Tony Lindgren <tony@atomide.com> Cc: Lars-Peter Clausen <lars@metafoo.de> Cc: Michael Hennerich <Michael.Hennerich@analog.com> Cc: Jonathan Cameron <jic23@kernel.org> Cc: Hartmut Knaack <knaack.h@gmx.de> Cc: Peter Meerwald-Stadler <pmeerw@pmeerw.net> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jiri Slaby <jslaby@suse.com> Cc: Yegor Yefremov <yegorslists@googlemail.com> Cc: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Janusz Krzysztofik <jmkrzyszt@gmail.com> Acked-by: Ulf Hansson <ulf.hansson@linaro.org> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Tested-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-09-13gpiolib: Don't support irq sharing for userspaceUwe Kleine-König
This concerns gpio edge detection for GPIO IRQs used from userspace for GPIO event listeners. Trying to work out the right event if it's not sure that the examined gpio actually moved is impossible. Consider two gpios "gpioA" and "gpioB" that share an interrupt. gpioA's irq should trigger on any edge, gpioB's on a falling edge. If now the common irq fires and both gpio lines are high, there are several possibilities that could have happend: a) gpioA just had a low-to-high edge b) gpioB just had a high-to-low-to-high spike c) a combination of both a) and b) While c) is unlikely (in most setups) a) and b) alone are bad enough. Currently the code assumes case a) unconditionally and doesn't report an event for gpioB. Note that even if there is no irq sharing involved a spike for a gpio might not result in an event if it's configured to trigger for a single edge only. The only way to improve this is to drop support for interrupt sharing. This way a spike results in an event for the right gpio at least. Note that apart from dropping IRQF_SHARED this effectively undoes commit df1e76f28ffe ("gpiolib: skip unwanted events, don't convert them to opposite edge"). This obviously breaks setups that rely on interrupt sharing, but given that this cannot be reliable, this is probably an acceptable trade-off. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> [Assuming there are no users of interrupt sharing yet] Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-09-10gpiolib: override irq_enable/disableHans Verkuil
When using the gpiolib irqchip helpers install irq_enable/disable hooks for the irqchip to ensure that gpiolib knows when the irq is enabled or disabled, allowing drivers to disable the irq and then use it as an output pin, and later switch the direction to input and re-enable the irq. Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-09-10gpiolib: add flag to indicate if the irq is disabledHans Verkuil
GPIO drivers call gpiochip_(un)lock_as_irq whenever they want to use a gpio as an interrupt. This is done when the irq is requested and it marks the gpio as in use by an interrupt. This is problematic for cases where a gpio pin is used as an interrupt pin, then, after the irq is disabled, is used as a regular gpio pin. Currently it is not possible to do this other than by first freeing the interrupt so gpiochip_unlock_as_irq is called, since an attempt to switch the gpio direction for output will fail since gpiolib believes that the gpio is in use for an interrupt and it does not know that it the irq is actually disabled. There are currently two drivers that would like to be able to do this: the tda998x_drv.c driver where a regular gpio pin needs to be temporarily reconfigured as an interrupt pin during CEC calibration, and the cec-gpio driver where you want to configure the gpio pin as an interrupt while waiting for traffic over the CEC bus, or as a regular pin when receiving or transmitting a CEC message. The solution is to add a new flag that is set when the irq is enabled, and have gpiod_direction_output check for that flag. We also add functions that drivers that do not use GPIOLIB_IRQCHIP can call when they enable/disable the irq. Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-09-10gliolib: set hooks in gpiochip_set_irq_hooks()Hans Verkuil
Centralize setting the irq_request/release_resources callbacks in one function since we'll be adding more callbacks to that. Also fix the removal of the callback overrides: this should only be done if we actually installed our own callback there. Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-09-10gpiolib: export gpiochip_irq_reqres/relres()Hans Verkuil
GPIO drivers that do not use GPIOLIB_IRQCHIP can hook these into the irq_request_resource and irq_release_resource callbacks of the irq_chip so they correctly 'get' the module and lock the gpio line for IRQ use. This will simplify driver code. Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-08-10gpiolib: Avoid calling chip->request() for unused gpiosBiju Das
Add a check for unused gpios to avoid chip->request() call to client driver for unused gpios. Signed-off-by: Biju Das <biju.das@bp.renesas.com> Reviewed-by: Fabrizio Castro <fabrizio.castro@bp.renesas.com> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-08-10gpiolib: Fix of_node inconsistencyBiju Das
Some platforms are not setting of_node in the driver. On these platforms defining gpio-reserved-ranges on device tree leads to kernel crash. It is due to some parts of the gpio core relying on the driver to set up of_node,while other parts do themselves.This inconsistent behaviour leads to a crash. gpiochip_add_data_with_key() calls gpiochip_init_valid_mask() with of_node as NULL. of_gpiochip_add() fills "of_node" and calls of_gpiochip_init_valid_mask(). The fix is to move the assignment to chip->of_node from of_gpiochip_add() to gpiochip_add_data_with_key(). Signed-off-by: Biju Das <biju.das@bp.renesas.com> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Tested-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-08-06gpiolib: Don't shadow error code of gpiochip_lock_as_irq()Andy Shevchenko
gpiochip_lock_as_irq() may return a few error codes, do not shadow them by -EINVAL and let caller to decide. No functional change intended. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-07-29gpiolib: probe deferral error reportingMarcel Ziswiler
Actually report the error code from devm_regulator_get() which may as well just be a probe deferral. This is e.g. what one gets upon booting a Colibri T20: gpiochip_add_data_with_key: GPIOs 0..223 (tegra-gpio) failed to register Signed-off-by: Marcel Ziswiler <marcel.ziswiler@toradex.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>