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13 hoursMerge tag 'gpio-updates-for-v6.17-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux Pull gpio updates from Bartosz Golaszewski: "There's one new driver (Apple SMC) and extensions to existing drivers for supporting new HW models. A lot of different impovements across drivers and in core GPIO code. Details on that are in the signed tag as usual. We managed to remove some of the legacy APIs. Arnd Bergmann started to work on making the legacy bits optional so that we may compile them only for older platforms that still really need them. Rob Herring has done a lot of work to convert legacy .txt dt-bindings for GPIO controllers to YAML. There are only a few left now in the GPIO tree. A big part of the commits in this PR concern the conversion of GPIO drivers to using the new line value setter callbacks. This conversion is now complete treewide (unless I've missed something) and once all the changes from different trees land in mainline, I'll send you another PR containing a commit dropping the legacy callbacks from the tree. As the quest to pay back technical dept never really ends, we're starting another set of interface conversions, this time it's about moving fields specific to only a handful of drivers using the gpio-mmio helper out of the core gpio_chip structure that every controller implements and uses. This cycle we introduce a new set of APIs and convert a few drivers under drivers/gpio/, next cycle we'll convert remaining modules treewide (in gpio, pinctrl and mfd trees) and finally remove the old interfaces and move the gpio-mmio fields into their own structure wrapping gpio_chip. One last change I should mention here is the rework of the sysfs interface. In 2016, we introduced the GPIO character device as the preferred alternative to the sysfs class under /sys/class/gpio. While it has seen a wide adoption with the help of its user-space counterpart - libgpiod - there are still users who prefer the simplicity of sysfs. As far as the GPIO subsystem is concerned, the problem is not the existince of the GPIO class as such but rather the fact that it exposes the global GPIO numbers to the user-space, stopping us from ever being able to remove the numberspace from the kernel. To that end, this release we introduced a parallel, limited sysfs interface that doesn't expose these numbers and only implements a subset of features that are relevant to the existing users. This is a result of several discussions over the course of last year and should allow us to remove the legacy part some time in the future. Summary: GPIOLIB core: - introduce a parallel, limited sysfs user ABI that doesn't expose the global GPIO numbers to user-space while maintaining backward compatibility with the end goal of it completely replacing the existing interface, allowing us to remove it - remove the legacy devm_gpio_request() routine which has no more users - start the process of allowing to compile-out the legacy parts of the GPIO core for users who don't need it by introducing a new Kconfig option: GPIOLIB_LEGACY - don't use global GPIO numbers in debugfs output from the core code (drivers still do it, the work is ongoing) - start the process of moving the fields specific to the gpio-mmio helper out of the core struct gpio_chip into their own structure that wraps it: create a new header with modern interfaces and convert several drivers to using it - remove the platform data structure associated with the gpio-mmio helper from the kernel after having converted all remaining users to generic device properties - remove legacy struct gpio definition as it has no more users New drivers: - add the GPIO driver for the Apple System Management Controller Driver improvements: - add support for new models to gpio-adp5585, gpio-tps65219 and gpio-pca953x - extend the interrupt support in gpio-loongson-64bit - allow to mark the simulated GPIO lines as invalid in gpio-sim - convert all remaining GPIO drivers to using the new GPIO value setter callbacks - convert gpio-rcar to using simple device power management ops callbacks - don't check if current direction of a line is output before setting the value in gpio-pisosr and ti-fpc202: the GPIO core already handles that - also drop unneeded GPIO range checks in drivers, the core already makes sure we're within bounds when calling driver callbacks - use dev_fwnode() where applicable across GPIO drivers - set line value in gpio-zynqmp-modepin and gpio-twl6040 when the user wants to change direction of the pin to output even though these drivers don't need to do anything else to actually set the direction, otherwise a call like gpiod_direction_output(d, 1) will not result in the line driver high - remove the reduntant call to pm_runtime_mark_last_busy() from gpio-arizona - use lock guards in gpio-cadence and gpio-mxc - check the return values of regmap functions in gpio-wcd934x and gpio-tps65912 - use better regmap interfaces in gpio-wcove and gpio-pca953x - remove dummy GPIO chip callbacks from several drivers in cases where the GPIO core can already handle their absence - allow building gpio-palmas as a module Fixes: - use correct bit widths (according to the documentation) in gpio-virtio Device-tree bindings: - convert several of the legacy .txt documents for many different devices to YAML, improving automatic validation - create a "trivial" GPIO DT schema that covers a wide range of simple hardware that share a set of basic GPIO properties - document new HW: Apple MAC SMC GPIO block and adp5589 I/O expander - document a new model for pca95xx - add and/or remove properties in YAML documents for gpio-rockchip, fsl,qoriq-gpio, arm,pl061 and gpio-xilinx Misc: - some minor refactoring in several places, adding/removing forward declarations, moving defines to better places, constify the arguments in some functions, remove duplicate includes, etc. - documentation updates" * tag 'gpio-updates-for-v6.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux: (202 commits) MIPS: alchemy: gpio: use new GPIO line value setter callbacks for the remaining chips gpiolib: enable CONFIG_GPIOLIB_LEGACY even for !GPIOLIB gpio: virtio: Fix config space reading. gpiolib: make legacy interfaces optional dt-bindings: gpio: rockchip: Allow use of a power-domain gpiolib: of: add forward declaration for struct device_node power: reset: macsmc-reboot: Add driver for rebooting via Apple SMC gpio: Add new gpio-macsmc driver for Apple Macs mfd: Add Apple Silicon System Management Controller soc: apple: rtkit: Make shmem_destroy optional dt-bindings: mfd: Add Apple Mac System Management Controller dt-bindings: power: reboot: Add Apple Mac SMC Reboot Controller dt-bindings: gpio: Add Apple Mac SMC GPIO block gpio: cadence: Remove duplicated include in gpio-cadence.c gpio: tps65219: Add support for TI TPS65214 PMIC gpio: tps65219: Update _IDX & _OFFSET macro prefix gpio: sysfs: Fix an end of loop test in gpiod_unexport() dt-bindings: gpio: Convert qca,ar7100-gpio to DT schema dt-bindings: gpio: Convert maxim,max3191x to DT schema dt-bindings: gpio: fsl,qoriq-gpio: Add missing mpc8xxx compatibles ...
2025-07-13gpiolib: don't use GPIO global numbers in debugfs outputBartosz Golaszewski
One of the users of global GPIO numbers in the kernel are the debugfs callbacks in GPIO drivers. Before converting any custom .dbg_show() callbacks in individual modules, let's first make GPIO core stop using GPIO base in debugfs output. Use hardware offsets instead. Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Link: https://lore.kernel.org/r/20250707141313.73169-1-brgl@bgdev.pl Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2025-07-04gpiolib: fix performance regression when using gpio_chip_get_multiple()Hugo Villeneuve
commit 74abd086d2ee ("gpiolib: sanitize the return value of gpio_chip::get_multiple()") altered the value returned by gc->get_multiple() in case it is positive (> 0), but failed to return for other cases (<= 0). This may result in the "if (gc->get)" block being executed and thus negates the performance gain that is normally obtained by using gc->get_multiple(). Fix by returning the result of gc->get_multiple() if it is <= 0. Also move the "ret" variable to the scope where it is used, which as an added bonus fixes an indentation error introduced by the aforementioned commit. Fixes: 74abd086d2ee ("gpiolib: sanitize the return value of gpio_chip::get_multiple()") Cc: stable@vger.kernel.org Signed-off-by: Hugo Villeneuve <hvilleneuve@dimonoff.com> Link: https://lore.kernel.org/r/20250703191829.2952986-1-hugo@hugovil.com Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2025-06-30gpio: make gpiod_is_equal() arguments stricterBartosz Golaszewski
It makes no sense for a GPIO descriptor comparator to return true when the arguments passed to it are NULL or IS_ERR(). Let's validate both and return false unless both are valid GPIO descriptors. Suggested-by: Andy Shevchenko <andriy.shevchenko@intel.com> Link: https://lore.kernel.org/all/Z_aFBfjb17JxOwyk@black.fi.intel.com/ Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Acked-by: Andy Shevchenko <andriy.shevchenko@intel.com> Link: https://lore.kernel.org/r/20250620-gpiod-is-equal-improv-v1-2-a75060505d2c@linaro.org Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2025-06-30gpio: constify arguments of gpiod_is_equal()Bartosz Golaszewski
This function is not meant to modify the GPIO descriptors in any way so we can safely constify both arguments. Link: https://lore.kernel.org/r/20250620-gpiod-is-equal-improv-v1-1-a75060505d2c@linaro.org Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2025-06-10gpiolib: Move GPIO_DYNAMIC_* constants to its only userAndy Shevchenko
There is no need to export GPIO_DYNAMIC_* constants, especially via legacy header which is subject to remove. Move the mentioned constants to its only user, i.e. gpiolib.c. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Link: https://lore.kernel.org/r/20250531195801.3632110-3-andriy.shevchenko@linux.intel.com Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2025-05-27Merge tag 'gpio-updates-for-v6.16-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux Pull gpio updates from Bartosz Golaszewski: "We have three new drivers, some refactoring in the GPIO core, lots of various changes across many drivers, new configfs interface for the virtual gpio-aggregator module and DT-bindings updates. The treewide conversion of GPIO drivers to using the new value setter callbacks is ongoing with another round of GPIO drivers updated. You will also see these commits coming in from other subsystems as with the relevant changes merged into mainline last cycle, I've started converting GPIO providers located elsewhere than drivers/gpio/. GPIO core: - use more lock guards where applicable - refactor GPIO ACPI code and shrink it in the process by 8% - move GPIO ACPI quirks into a separate file - remove unneeded #ifdef - convert GPIO devres helpers to using devm_add_action() where applicable which shrinks and simplifies the code - refactor GPIO descriptor validation in GPIO consumer interfaces - don't allow setting values on input lines in the GPIO core which will take off the burden from GPIO drivers of checking this down the line - provide gpiod_is_equal() as a way of safely comparing two GPIO descriptors (the only current user is in regulator core) New drivers: - add the GPIO module for the max77759 multifunction device - add the GPIO driver for the VeriSilicon BLZP1600 GPIO controller - add the GPIO driver for the Spacemit K1 SoC Driver improvements: - convert more drivers to using the new GPIO line value setter callbacks - convert more drivers to making the irq_chip immutable as is recommended by the interrupt subsystem - extend build testing coverage by enabling more modules to be built with COMPILE_TEST=y - extend the gpio-aggregator module with a configfs interface that makes the setup easier for user-space than the existing driver-level sysfs attributes and also adds more advanced configuration features (such as referring to aggregated lines by their original names or modifying their names as exposed by the aggregated chip) - add a missing mutex_destroy() in gpio-imx-scu - add an OF polarity quirk for s5m8767 - allow building gpio-vf610 as a loadable module - make gpio-mxc not hardcode its GPIO base number with GPIO SYSFS interface disabled (another small step towards getting rid of the global GPIO numberspace) - add support for level-triggered interrupts to gpio-pca953x - don't double-check the ngpios property in gpio-ds4520 as GPIO core already does it - don't double-check the number of GPIOs in gpio-imx-scu as GPIO core already does it - remove unused callbacks from gpio-max3191x DT bindings: - add device-tree bindings for max77759, spacemit,k1 and blzp1600 (new drivers added this cycle) - document more properties for gpio-vf610 and gpio-tegra186 - document a new pca95xx variant - fix style of examples in several GPIO DT-binding documents Misc: - TODO list updates" * tag 'gpio-updates-for-v6.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux: (123 commits) gpio: timberdale: select GPIOLIB_IRQCHIP gpio: lpc18xx: select GPIOLIB_IRQCHIP gpio: grgpio: select GPIOLIB_IRQCHIP gpio: bcm-kona: select GPIOLIB_IRQCHIP dt-bindings: gpio: vf610: add ngpios and gpio-reserved-ranges gpio: davinci: select GPIOLIB_IRQCHIP gpiolib-acpi: Update file references in the Documentation and MAINTAINERS gpiolib: acpi: Move quirks to a separate file gpiolib: acpi: Add acpi_gpio_need_run_edge_events_on_boot() getter gpiolib: acpi: Handle deferred list via new API gpiolib: acpi: Make sure we fill struct acpi_gpio_info gpiolib: acpi: Switch to use enum in acpi_gpio_in_ignore_list() gpiolib: acpi: Use temporary variable for struct acpi_gpio_info gpiolib: remove unneeded #ifdef gpio: mpc8xxx: select GPIOLIB_IRQCHIP gpio: pxa: select GPIOLIB_IRQCHIP gpio: pxa: Make irq_chip immutable gpio: timberdale: Make irq_chip immutable gpio: xgene-sb: Make irq_chip immutable gpio: davinci: Make irq_chip immutable ...
2025-05-20gpiolib: don't crash on enabling GPIO HOG pinsDmitry Baryshkov
On Qualcomm platforms if the board uses GPIO hogs msm_pinmux_request() calls gpiochip_line_is_valid(). After commit 8015443e24e7 ("gpio: Hide valid_mask from direct assignments") gpiochip_line_is_valid() uses gc->gpiodev, which is NULL when GPIO hog pins are being processed. Thus after this commit using GPIO hogs causes the following crash. In order to fix this, verify that gc->gpiodev is not NULL. Note: it is not possible to reorder calls (e.g. by calling msm_gpio_init() before pinctrl registration or by splitting pinctrl_register() into _and_init() and pinctrl_enable() and calling the latter function after msm_gpio_init()) because GPIO chip registration would fail with EPROBE_DEFER if pinctrl is not enabled at the time of registration. pc : gpiochip_line_is_valid+0x4/0x28 lr : msm_pinmux_request+0x24/0x40 sp : ffff8000808eb870 x29: ffff8000808eb870 x28: 0000000000000000 x27: 0000000000000000 x26: 0000000000000000 x25: ffff726240f9d040 x24: 0000000000000000 x23: ffff7262438c0510 x22: 0000000000000080 x21: ffff726243ea7000 x20: ffffab13f2c4e698 x19: 0000000000000080 x18: 00000000ffffffff x17: ffff726242ba6000 x16: 0000000000000100 x15: 0000000000000028 x14: 0000000000000000 x13: 0000000000002948 x12: 0000000000000003 x11: 0000000000000078 x10: 0000000000002948 x9 : ffffab13f50eb5e8 x8 : 0000000003ecb21b x7 : 000000000000002d x6 : 0000000000000b68 x5 : 0000007fffffffff x4 : ffffab13f52f84a8 x3 : ffff8000808eb804 x2 : ffffab13f1de8190 x1 : 0000000000000080 x0 : 0000000000000000 Call trace: gpiochip_line_is_valid+0x4/0x28 (P) pin_request+0x208/0x2c0 pinmux_enable_setting+0xa0/0x2e0 pinctrl_commit_state+0x150/0x26c pinctrl_enable+0x6c/0x2a4 pinctrl_register+0x3c/0xb0 devm_pinctrl_register+0x58/0xa0 msm_pinctrl_probe+0x2a8/0x584 sdm845_pinctrl_probe+0x20/0x88 platform_probe+0x68/0xc0 really_probe+0xbc/0x298 __driver_probe_device+0x78/0x12c driver_probe_device+0x3c/0x160 __device_attach_driver+0xb8/0x138 bus_for_each_drv+0x84/0xe0 __device_attach+0x9c/0x188 device_initial_probe+0x14/0x20 bus_probe_device+0xac/0xb0 deferred_probe_work_func+0x8c/0xc8 process_one_work+0x208/0x5e8 worker_thread+0x1b4/0x35c kthread+0x144/0x220 ret_from_fork+0x10/0x20 Code: b5fffba0 17fffff2 9432ec27 f9400400 (f9428800) Fixes: 8015443e24e7 ("gpio: Hide valid_mask from direct assignments") Reported-by: Doug Anderson <dianders@chromium.org> Closes: https://lore.kernel.org/r/CAD=FV=Vg8_ZOLgLoC4WhFPzhVsxXFC19NrF38W6cW_W_3nFjbw@mail.gmail.com Tested-by: Douglas Anderson <dianders@chromium.org> Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com> Reviewed-by: Matti Vaittinen <mazziesaccount@gmail.com> Acked-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org> Link: https://lore.kernel.org/20250513-pinctrl-msm-fix-v2-1-249999af0fc1@oss.qualcomm.com Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2025-05-20gpiolib: remove unneeded #ifdefBartosz Golaszewski
We are already within another `#ifdef CONFIG_GPIOLIB_IRQCHIP` in gpiochip_to_irq() so there's no need for another guard. Remove it. Acked-by: Peng Fan <peng.fan@nxp.com> Link: https://lore.kernel.org/r/20250519-gpio-irq-kconfig-fixes-v1-3-fe6ba1c6116d@linaro.org Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2025-04-17gpiolib: Remove redundant assignment of return variableAndy Shevchenko
In some functions the returned variable is assigned to 0 and then reassigned to the actual value. Remove redundant assignments. In one case make it more clear that the assignment is not needed. Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20250416095645.2027695-9-andriy.shevchenko@linux.intel.com Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
2025-04-17gpiolib: Reuse return variable in gpiod_to_irq()Andy Shevchenko
There are two variables for the same used in the gpiod_to_irq(). Replace the second by reusing the function top-level one. While at it, refactor the branch to have less lines of code. Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20250416095645.2027695-8-andriy.shevchenko@linux.intel.com Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
2025-04-17gpiolib: Call validate_desc() when VALIDATE_DESC() can't be usedAndy Shevchenko
Call validate_desc() directly when VALIDATE_DESC() can't be used. It will print additional information useful for debugging. Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20250416095645.2027695-7-andriy.shevchenko@linux.intel.com Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
2025-04-17gpiolib: Move validate_desc() and Co upper in the codeAndy Shevchenko
Move validate_desc() and Co upper in the code to be able to use in the further changes. Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20250416095645.2027695-6-andriy.shevchenko@linux.intel.com Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
2025-04-17gpiolib: Revert "Don't WARN on gpiod_put() for optional GPIO"Andy Shevchenko
No need to double check the pointer for NULL since gpiod_free() is using VALIDATE_DESC_VOID() which simply returns in that case. This reverts commit 1d7765ba15aca68f3bc52f59434c1c34855bbb54. Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20250416095645.2027695-5-andriy.shevchenko@linux.intel.com Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
2025-04-17gpiolib: Print actual error when descriptor contains an error pointerAndy Shevchenko
Print the actual error when descriptor contains an error pointer. This might help debugging those rare cases. Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20250416095645.2027695-4-andriy.shevchenko@linux.intel.com Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
2025-04-17gpiolib: Convert to use guard()() for gpio_machine_hogs_mutexAndy Shevchenko
The driver uses guard()()/scoped_guard() for the rest of the synchronisation calls. Convert to use the same for gpio_machine_hogs_mutex. Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20250416095645.2027695-3-andriy.shevchenko@linux.intel.com Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
2025-04-17gpiolib: Make taking gpio_lookup_lock consistentAndy Shevchenko
There are two ways to take a lock: plain call to the mutex_lock() or using guard()() / scoped_guard(). The driver inconsistently uses both. Make taking gpio_lookup_lock consistent. Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20250416095645.2027695-2-andriy.shevchenko@linux.intel.com Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
2025-04-14gpiolib: Allow to use setters with return value for output-only gpiosMathieu Dubois-Briand
The gpiod_direction_output_raw_commit() function checks if any setter callback is present before doing anything. As the new GPIO setters with return values were introduced, make this check also succeed if one is present. Fixes: 98ce1eb1fd87 ("gpiolib: introduce gpio_chip setters that return values") Signed-off-by: Mathieu Dubois-Briand <mathieu.dubois-briand@bootlin.com> Link: https://lore.kernel.org/r/20250411-mdb-gpiolib-setters-fix-v2-1-9611280d8822@bootlin.com Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
2025-04-09Merge tag 'gpiod-is-equal-for-v6.16-rc1' of ↵Bartosz Golaszewski
gitolite.kernel.org:pub/scm/linux/kernel/git/brgl/linux into gpio/for-next Immutable tag for the regulator tree to pull from gpio: provide gpiod_is_equal()
2025-04-09gpio: provide gpiod_is_equal()Bartosz Golaszewski
There are users in the kernel that directly compare raw GPIO descriptor pointers in order to determine whether they refer to the same physical GPIO pin. This accidentally works like this but is not guaranteed by any API contract. Let's provide a comparator function that hides the actual logic. Reviewed-by: Mark Brown <broonie@kernel.org> Link: https://lore.kernel.org/r/20250407-gpiod-is-equal-v1-1-7d85f568ae6e@linaro.org Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2025-04-08gpiolib: support parsing gpio three-cell interrupts schemeYixun Lan
gpio irq which using three-cell scheme should always call instance_match() function to find the correct irqdomain. The select() function will be called with !DOMAIN_BUS_ANY, so for specific gpio irq driver, it need to set bus token explicitly, something like: irq_domain_update_bus_token(girq->domain, DOMAIN_BUS_WIRED); Signed-off-by: Yixun Lan <dlan@gentoo.org> Link: https://lore.kernel.org/r/20250408-04-gpio-irq-threecell-v4-1-fd170d5e2d2b@gentoo.org Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2025-04-07gpiolib: don't allow setting values on input linesBartosz Golaszewski
Some drivers as well as the character device and sysfs code check whether the line actually is in output mode before allowing the user to set a value. However, GPIO value setters now return integer values and can indicate failures. This allows us to move these checks into the core code. Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Link: https://lore.kernel.org/r/20250311-gpio-set-check-output-v1-1-d971bca9e6fa@linaro.org Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2025-03-17Merge tag 'v6.14-rc7' of ↵Bartosz Golaszewski
git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux into gpio/for-next Linux 6.14-rc7
2025-03-13gpio: cdev: use raw notifier for line state eventsBartosz Golaszewski
We use a notifier to implement the mechanism of informing the user-space about changes in GPIO line status. We register with the notifier when the GPIO character device file is opened and unregister when the last reference to the associated file descriptor is dropped. Since commit fcc8b637c542 ("gpiolib: switch the line state notifier to atomic") we use the atomic notifier variant. Atomic notifiers call rcu_synchronize in atomic_notifier_chain_unregister() which caused a significant performance regression in some circumstances, observed by user-space when calling close() on the GPIO device file descriptor. Replace the atomic notifier with the raw variant and provide synchronization with a read-write spinlock. Fixes: fcc8b637c542 ("gpiolib: switch the line state notifier to atomic") Reported-by: David Jander <david@protonic.nl> Closes: https://lore.kernel.org/all/20250311110034.53959031@erd003.prtnl/ Tested-by: David Jander <david@protonic.nl> Tested-by: Kent Gibson <warthog618@gmail.com> Link: https://lore.kernel.org/r/20250311-gpiolib-line-state-raw-notifier-v2-1-138374581e1e@linaro.org Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2025-03-13gpiolib: don't check the retval of get_direction() when registering a chipBartosz Golaszewski
During chip registration we should neither check the return value of gc->get_direction() nor hold the SRCU lock when calling it. The former is because pin controllers may have pins set to alternate functions and return errors from their get_direction() callbacks. That's alright - we should default to the safe INPUT state and not bail-out. The latter is not needed because we haven't registered the chip yet so there's nothing to protect against dynamic removal. In fact: we currently hit a lockdep splat. Revert to calling the gc->get_direction() callback directly and *not* checking its value. Fixes: 9d846b1aebbe ("gpiolib: check the return value of gpio_chip::get_direction()") Reported-by: Marek Szyprowski <m.szyprowski@samsung.com> Closes: https://lore.kernel.org/all/81f890fc-6688-42f0-9756-567efc8bb97a@samsung.com/ Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Tested-by: Marek Szyprowski <m.szyprowski@samsung.com> Link: https://lore.kernel.org/r/20250226-retval-fixes-v2-1-c8dc57182441@linaro.org Tested-by: Gene C <arch@sapience.com> Link: https://lore.kernel.org/r/20250311175631.83779-1-brgl@bgdev.pl Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2025-03-05gpio: Hide valid_mask from direct assignmentsMatti Vaittinen
The valid_mask member of the struct gpio_chip is unconditionally written by the GPIO core at driver registration. Current documentation does not mention this but just says the valid_mask is used if it's not NULL. This lured me to try populating it directly in the GPIO driver probe instead of using the init_valid_mask() callback. It took some retries with different bitmaps and eventually a bit of code-reading to understand why the valid_mask was not obeyed. I could've avoided this trial and error if the valid_mask was hidden in the struct gpio_device instead of being a visible member of the struct gpio_chip. Help the next developer who decides to directly populate the valid_mask in struct gpio_chip by hiding the valid_mask in struct gpio_device and keep it internal to the GPIO core. Suggested-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Matti Vaittinen <mazziesaccount@gmail.com> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Link: https://lore.kernel.org/r/4547ca90d910d60cab3d56d864d59ddde47a5e93.1741180097.git.mazziesaccount@gmail.com Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2025-03-05gpio: Add a valid_mask getterMatti Vaittinen
The valid_mask member of the struct gpio_chip is unconditionally written by the GPIO core at driver registration. It shouldn't be directly populated by drivers. This can be prevented by moving it from the struct gpio_chip to struct gpio_device, which is internal to the GPIO core. As a preparatory step, provide a getter function which can be used by those drivers which need the valid_mask information. Signed-off-by: Matti Vaittinen <mazziesaccount@gmail.com> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Link: https://lore.kernel.org/r/026f9d78502eca883bfe3faeb684e23d5d6c5e84.1741180097.git.mazziesaccount@gmail.com Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2025-03-05gpio: Respect valid_mask when requesting GPIOsMatti Vaittinen
When GPIOs were requested the validity of GPIOs were checked only when the GPIO-chip had the request -callback populated. This made using masked GPIOs possible. The GPIO chip driver authors may find it difficult to understand the relation of enforsing the GPIO validity and the 'request' -callback because the current documentation for the 'request' callback does not mention this. It only states: * @request: optional hook for chip-specific activation, such as * enabling module power and clock; may sleep The validity of the GPIO line should be checked whether the driver provides the 'request' callback or not. Unconditionally check the GPIO validity when GPIO is being requested. Signed-off-by: Matti Vaittinen <mazziesaccount@gmail.com> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Link: https://lore.kernel.org/r/cd5e067b80e1bb590027bc3bfa817e7f794f21c3.1741180097.git.mazziesaccount@gmail.com Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2025-03-03gpiolib: update kerneldocs for value settersBartosz Golaszewski
Value setters now return int and can indicate failure. Update the kerneldocs. Link: https://lore.kernel.org/r/20250227083748.22400-2-brgl@bgdev.pl Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2025-03-03gpiolib: remove unneeded WARN_ON() from gpiochip_set_multiple()Bartosz Golaszewski
GPIO drivers are not required to support set_multiple() - the core will fallback to calling set() for each line if it's missing. Remove the offending check from gpiochip_set_multiple(). Fixes: 98ce1eb1fd87 ("gpiolib: introduce gpio_chip setters that return values") Reported-by: Marek Szyprowski <m.szyprowski@samsung.com> Closes: https://lore.kernel.org/all/ab3e42c0-70fa-48e0-ac93-ecbffef63507@samsung.com/ Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Link: https://lore.kernel.org/r/20250227152831.59784-1-brgl@bgdev.pl Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2025-03-03Merge tag 'v6.14-rc5' of ↵Bartosz Golaszewski
git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux into gpio/for-next Linux 6.14-rc5
2025-02-28gpiolib: Fix Oops in gpiod_direction_input_nonotify()Dan Carpenter
The gpiod_direction_input_nonotify() function is supposed to return zero if the direction for the pin is input. But instead it accidentally returns GPIO_LINE_DIRECTION_IN (1) which will be cast into an ERR_PTR() in gpiochip_request_own_desc(). The callers dereference it and it leads to a crash. I changed gpiod_direction_output_raw_commit() just for consistency but returning GPIO_LINE_DIRECTION_OUT (0) is fine. Cc: stable@vger.kernel.org Fixes: 9d846b1aebbe ("gpiolib: check the return value of gpio_chip::get_direction()") Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org> Link: https://lore.kernel.org/r/254f3925-3015-4c9d-aac5-bb9b4b2cd2c5@stanley.mountain [Bartosz: moved the variable declarations to the top of the functions] Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2025-02-27gpiolib: don't double-check the gc->get callback's existenceBartosz Golaszewski
gpiochip_get() is called only in two places: in gpio_chip_get_value() and in gpiochip_get_multiple() where the existence of the gc->get() callback is already checked. It makes sense to unduplicate the check by moving it one level up the stack. Fixes: 86ef402d805d ("gpiolib: sanitize the return value of gpio_chip::get()") Suggested-by: Andy Shevchenko <andriy.shevchenko@intel.com> Closes: https://lore.kernel.org/all/Z7yekJ8uRh8dphKn@black.fi.intel.com/ Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20250226-retval-fixes-v2-3-c8dc57182441@linaro.org Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2025-02-27gpiolib: use a more explicit retval logic in gpiochip_get_direction()Bartosz Golaszewski
We have existing macros for direction settings so we don't need to rely on the magic value of 1 in the retval check. Use readable logic that explicitly says we expect INPUT, OUTPUT or a negative errno and nothing else in gpiochip_get_direction(). Fixes: e623c4303ed1 ("gpiolib: sanitize the return value of gpio_chip::get_direction()") Suggested-by: Andy Shevchenko <andriy.shevchenko@intel.com> Closes: https://lore.kernel.org/all/Z7yfTggRrk3K6srs@black.fi.intel.com/ Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20250226-retval-fixes-v2-2-c8dc57182441@linaro.org Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2025-02-27gpiolib: don't use gpiochip_get_direction() when registering a chipBartosz Golaszewski
During chip registration we should neither check the return value of gc->get_direction() nor hold the SRCU lock when calling it. The former is because pin controllers may have pins set to alternate functions and return errors from their get_direction() callbacks. That's alright - we should default to the safe INPUT state and not bail-out. The latter is not needed because we haven't registered the chip yet so there's nothing to protect against dynamic removal. In fact: we currently hit a lockdep splat. Revert to calling the gc->get_direction() callback directly and *not* checking its value. Fixes: 9d846b1aebbe ("gpiolib: check the return value of gpio_chip::get_direction()") Fixes: e623c4303ed1 ("gpiolib: sanitize the return value of gpio_chip::get_direction()") Reported-by: Marek Szyprowski <m.szyprowski@samsung.com> Closes: https://lore.kernel.org/all/81f890fc-6688-42f0-9756-567efc8bb97a@samsung.com/ Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Tested-by: Marek Szyprowski <m.szyprowski@samsung.com> Link: https://lore.kernel.org/r/20250226-retval-fixes-v2-1-c8dc57182441@linaro.org Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2025-02-26gpiolib: introduce gpio_chip setters that return valuesBartosz Golaszewski
Add new variants of the set() and set_multiple() callbacks that have integer return values allowing to indicate failures to users of the GPIO consumer API. Until we convert all GPIO providers treewide to using them, they will live in parallel to the existing ones. Make sure that providers cannot define both. Prefer the new ones and only use the old ones as fallback. Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Acked-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com> Link: https://lore.kernel.org/r/20250220-gpio-set-retval-v2-5-bc4cfd38dae3@linaro.org Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2025-02-26gpiolib: rework the wrapper around gpio_chip::set_multiple()Bartosz Golaszewski
Make the existing wrapper around gpio_chip::set_multiple() consistent with the one for gpio_chip::set(): make it return int, add a lockdep assertion, warn on missing set callback and move the code a bit for better readability. Add return value checks in all call places. Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Acked-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com> Link: https://lore.kernel.org/r/20250220-gpio-set-retval-v2-4-bc4cfd38dae3@linaro.org Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2025-02-26gpiolib: wrap gpio_chip::set()Bartosz Golaszewski
We have three places where we dereference the gpio_chip::set() callback. In order to make it easier to incorporate the upcoming new variant of this callback (one returning an integer value), wrap it in a helper so that the dereferencing only happens once. Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Acked-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com> Link: https://lore.kernel.org/r/20250220-gpio-set-retval-v2-3-bc4cfd38dae3@linaro.org Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2025-02-26gpiolib: make value setters have return valuesBartosz Golaszewski
Change the in-kernel consumer interface for GPIOs: make all variants of value setters that don't have a return value, return a signed integer instead. That will allow these routines to indicate failures to callers. This doesn't change the implementation just yet, we'll do it in subsequent commits. We need to update the gpio-latch module as it passes the address of value setters as a function pointer argument and thus cares about its type. Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Acked-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com> Link: https://lore.kernel.org/r/20250220-gpio-set-retval-v2-2-bc4cfd38dae3@linaro.org Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2025-02-24gpiolib: read descriptor flags once in gpiolib_dbg_show()Bartosz Golaszewski
For consistency with most other code that can access requested descriptors: read the flags once atomically and then test individual bits from the helper variable. This avoids any potential discrepancies should flags change during the debug print. Link: https://lore.kernel.org/r/20250215100847.30136-1-brgl@bgdev.pl Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2025-02-24gpiolib: sanitize the return value of gpio_chip::get_direction()Bartosz Golaszewski
As per the API contract, the get_direction() callback can only return 0, 1 or a negative error number. Add a wrapper around the callback calls that filters out anything else. Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Link: https://lore.kernel.org/r/20250210-gpio-sanitize-retvals-v1-8-12ea88506cb2@linaro.org Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2025-02-24gpiolib: sanitize the return value of gpio_chip::direction_input()Bartosz Golaszewski
The return value of the direction_input() callback may be propagated to user-space. As per the API contract it can only return 0 or a negative error number. Add a wrapper around the callback calls that filters out anything else. Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Link: https://lore.kernel.org/r/20250210-gpio-sanitize-retvals-v1-7-12ea88506cb2@linaro.org Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2025-02-24gpiolib: sanitize the return value of gpio_chip::direction_output()Bartosz Golaszewski
The return value of the direction_output() callback may be propagated to user-space. As per the API contract it can only return 0 or a negative error number. Add a wrapper around the callback calls that filters out anything else. Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Link: https://lore.kernel.org/r/20250210-gpio-sanitize-retvals-v1-6-12ea88506cb2@linaro.org Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2025-02-24gpiolib: sanitize the return value of gpio_chip::get_multiple()Bartosz Golaszewski
As per the API contract, the get_multiple() callback is only allowed to return 0 or a negative error number. Filter out anything else. Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Link: https://lore.kernel.org/r/20250210-gpio-sanitize-retvals-v1-5-12ea88506cb2@linaro.org Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2025-02-24gpiolib: sanitize the return value of gpio_chip::get()Bartosz Golaszewski
As per the API contract, the get() callback is only allowed to return 0, 1 or a negative error number. Add a wrapper around the callback calls that filters out anything else. Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Link: https://lore.kernel.org/r/20250210-gpio-sanitize-retvals-v1-4-12ea88506cb2@linaro.org Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2025-02-24gpiolib: sanitize the return value of gpio_chip::set_config()Bartosz Golaszewski
The return value of the set_config() callback may be propagated to user-space. If a bad driver returns a positive number, it may confuse user programs. Tighten the API contract and check for positive numbers returned by GPIO controllers. Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Link: https://lore.kernel.org/r/20250210-gpio-sanitize-retvals-v1-3-12ea88506cb2@linaro.org Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2025-02-24gpiolib: sanitize the return value of gpio_chip::request()Bartosz Golaszewski
The return value of the request() callback may be propagated to user-space. If a bad driver returns a positive number, it may confuse user programs. Tighten the API contract and check for positive numbers returned by GPIO controllers. Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Link: https://lore.kernel.org/r/20250210-gpio-sanitize-retvals-v1-2-12ea88506cb2@linaro.org Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2025-02-24Merge tag 'v6.14-rc4' of ↵Bartosz Golaszewski
git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux into HEAD Linux 6.14-rc4
2025-02-21gpiolib: Use fwnode instead of device in gpiochip_get_ngpios()Andy Shevchenko
The gpiochip_get_ngpios() can be used in the cases where passed device is not a provider of the certain property. Use fwnode instead. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Tested-by: Mathieu Dubois-Briand <mathieu.dubois-briand@bootlin.com> Reviewed-by: Mathieu Dubois-Briand <mathieu.dubois-briand@bootlin.com> Link: https://lore.kernel.org/r/20250213195621.3133406-3-andriy.shevchenko@linux.intel.com Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2025-02-21gpiolib: Extract gpiochip_choose_fwnode() for wider useAndy Shevchenko
Extract gpiochip_choose_fwnode() for the future use in another function. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Tested-by: Mathieu Dubois-Briand <mathieu.dubois-briand@bootlin.com> Reviewed-by: Mathieu Dubois-Briand <mathieu.dubois-briand@bootlin.com> Link: https://lore.kernel.org/r/20250213195621.3133406-2-andriy.shevchenko@linux.intel.com Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>