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path: root/drivers/gpio/gpiolib.c
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2024-11-04gpiolib: clean up debugfs separator handlingJohan Hovold
Add the newline separator before generating the gpio chip entry to make the code easier to read. Signed-off-by: Johan Hovold <johan+linaro@kernel.org> Link: https://lore.kernel.org/r/20241028125000.24051-4-johan+linaro@kernel.org Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2024-11-04Merge tag 'v6.12-rc6' of ↵Bartosz Golaszewski
git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux into gpio/for-next Linux 6.12-rc6
2024-10-31gpiolib: fix debugfs dangling chip separatorJohan Hovold
Add the missing newline after entries for recently removed gpio chips so that the chip sections are separated by a newline as intended. Fixes: e348544f7994 ("gpio: protect the list of GPIO devices with SRCU") Cc: stable@vger.kernel.org # 6.9 Cc: Bartosz Golaszewski <bartosz.golaszewski@linaro.org> Signed-off-by: Johan Hovold <johan+linaro@kernel.org> Link: https://lore.kernel.org/r/20241028125000.24051-3-johan+linaro@kernel.org Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2024-10-31gpiolib: fix debugfs newline separatorsJohan Hovold
The gpiolib debugfs interface exports a list of all gpio chips in a system and the state of their pins. The gpio chip sections are supposed to be separated by a newline character, but a long-standing bug prevents the separator from being included when output is generated in multiple sessions, making the output inconsistent and hard to read. Make sure to only suppress the newline separator at the beginning of the file as intended. Fixes: f9c4a31f6150 ("gpiolib: Use seq_file's iterator interface") Cc: stable@vger.kernel.org # 3.7 Cc: Thierry Reding <treding@nvidia.com> Signed-off-by: Johan Hovold <johan+linaro@kernel.org> Link: https://lore.kernel.org/r/20241028125000.24051-2-johan+linaro@kernel.org Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2024-10-31gpiolib: remove leftover spinlock bitsBartosz Golaszewski
We no longer use any spinlocks in gpiolib.c. Stop including linux/spinlock.h and remove an outdated comment. Link: https://lore.kernel.org/r/20241024191532.78304-1-brgl@bgdev.pl Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2024-10-24gpiolib: fix a NULL-pointer dereference when setting directionBartosz Golaszewski
For optional GPIOs we may pass NULL to gpiod_direction_(input|output)(). With the call to the notifier chain added by commit 07c61d4da43f ("gpiolib: notify user-space about in-kernel line state changes") we will now dereference a NULL pointer in this case. The reason for that is the fact that the expansion of the VALIDATE_DESC() macro (which returns 0 for NULL descriptors) was moved into the nonotify variants of the direction setters. Move them back to the top-level interfaces as the nonotify ones are only ever called from inside the GPIO core and are always passed valid GPIO descriptors. This way we'll never call the line_state notifier chain with non-valid descs. Fixes: 07c61d4da43f ("gpiolib: notify user-space about in-kernel line state changes") Reported-by: Mark Brown <broonie@kernel.org> Closes: https://lore.kernel.org/all/d6601a31-7685-4b21-9271-1b76116cc483@sirena.org.uk/ Tested-by: Klara Modin <klarasmodin@gmail.com> Tested-by: Mark Brown <broonie@kernel.org> Link: https://lore.kernel.org/r/20241024133834.47395-1-brgl@bgdev.pl Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2024-10-22gpiolib: notify user-space about in-kernel line state changesBartosz Golaszewski
We currently only notify user-space about line config changes that are made from user-space. Any kernel config changes are not signalled. Let's improve the situation by emitting the events closer to the source. To that end let's call the relevant notifier chain from the functions setting direction, gpiod_set_config(), gpiod_set_consumer_name() and gpiod_toggle_active_low(). This covers all the options that we can inform the user-space about. We ignore events which don't have corresponding flags exported to user-space on purpose - otherwise the user would see a config-changed event but the associated line-info would remain unchanged. gpiod_direction_output/input() can be called from any context. Fortunately, we now emit line state events using an atomic notifier chain, so it's no longer an issue. Let's also add non-notifying wrappers around the direction setters in order to not emit superfluous reconfigure events when requesting the lines as the initial config should be part of the request notification. Use gpio_do_set_config() instead of gpiod_set_debounce() for configuring debouncing via hardware from the character device code to avoid multiple reconfigure events. Reviewed-by: Kent Gibson <warthog618@gmail.com> Link: https://lore.kernel.org/r/20241018-gpio-notify-in-kernel-events-v5-8-c79135e58a1c@linaro.org Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2024-10-22gpiolib: switch the line state notifier to atomicBartosz Golaszewski
With everything else ready, we can now switch to using the atomic notifier for line state events which will allow us to notify user-space about direction changes from atomic context. Reviewed-by: Kent Gibson <warthog618@gmail.com> Link: https://lore.kernel.org/r/20241018-gpio-notify-in-kernel-events-v5-7-c79135e58a1c@linaro.org Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2024-10-22gpio: cdev: go back to storing debounce period in the GPIO descriptorBartosz Golaszewski
This effectively reverts commits 9344e34e7992 ("gpiolib: cdev: relocate debounce_period_us from struct gpio_desc") and d8543cbaf979 ("gpiolib: remove debounce_period_us from struct gpio_desc") and goes back to storing the debounce period in microseconds in the GPIO descriptor We're doing it in preparation for notifying the user-space about in-kernel line config changes. Reviewed-by: Kent Gibson <warthog618@gmail.com> Link: https://lore.kernel.org/r/20241018-gpio-notify-in-kernel-events-v5-3-c79135e58a1c@linaro.org Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2024-10-22gpiolib: unduplicate chip guard in set_config pathBartosz Golaszewski
We don't need to guard the GPIO chip until its first dereference in gpio_do_set_config(). First: change the prototype of gpio_do_set_config() to take the GPIO line descriptor as argument, then move the gpio_chip protection into it and drop it in two places where it's done too early. This has the added benefit of making gpio_go_set_config() safe to use from outside of this compilation unit without taking the gdev SRCU read lock and will come in handy when we'll want to make it available to the character device code. Reviewed-by: Kent Gibson <warthog618@gmail.com> Link: https://lore.kernel.org/r/20241018-gpio-notify-in-kernel-events-v5-2-c79135e58a1c@linaro.org Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2024-10-22gpiolib: notify user-space when a driver requests its own descBartosz Golaszewski
We notify user-space about lines being requested from user-space or by drivers calling gpiod_get() but not when drivers request their own lines so add the missing call to gpiod_line_state_notify(). Reviewed-by: Kent Gibson <warthog618@gmail.com> Link: https://lore.kernel.org/r/20241018-gpio-notify-in-kernel-events-v5-1-c79135e58a1c@linaro.org Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2024-10-14Merge tag 'v6.12-rc3' of ↵Bartosz Golaszewski
git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux into gpio/for-next Linux 6.12-rc3
2024-10-08gpiolib: unify two loops initializing GPIO descriptorsBartosz Golaszewski
We currently iterate over the descriptors owned by the GPIO device we're adding twice with the first loop just setting the gdev pointer. It's not used anywhere between this and the second loop so just drop the first one and move the assignment to the second. Reviewed-by: Kent Gibson <warthog618@gmail.com> Link: https://lore.kernel.org/r/20241004-gpio-notify-in-kernel-events-v1-2-8ac29e1df4fe@linaro.org Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2024-10-08gpiolib: use v2 defines for line state change eventsBartosz Golaszewski
We should only use v2 defines for line state change events. They will get tranlated to v1 if needed by gpio_v2_line_info_changed_to_v1(). This isn't really a functional change as they have the same values but let's do it for consistency. Reviewed-by: Kent Gibson <warthog618@gmail.com> Link: https://lore.kernel.org/r/20241004-gpio-notify-in-kernel-events-v1-1-8ac29e1df4fe@linaro.org Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2024-10-03gpiolib: Fix potential NULL pointer dereference in gpiod_get_label()Lad Prabhakar
In `gpiod_get_label()`, it is possible that `srcu_dereference_check()` may return a NULL pointer, leading to a scenario where `label->str` is accessed without verifying if `label` itself is NULL. This patch adds a proper NULL check for `label` before accessing `label->str`. The check for `label->str != NULL` is removed because `label->str` can never be NULL if `label` is not NULL. This fixes the issue where the label name was being printed as `(efault)` when dumping the sysfs GPIO file when `label == NULL`. Fixes: 5a646e03e956 ("gpiolib: Return label, if set, for IRQ only line") Fixes: a86d27693066 ("gpiolib: fix the speed of descriptor label setting with SRCU") Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com> Link: https://lore.kernel.org/r/20241003131351.472015-1-prabhakar.mahadev-lad.rj@bp.renesas.com Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2024-09-30gpio: free irqs that are still requested when the chip is being removedBartosz Golaszewski
If we remove a GPIO chip that is also an interrupt controller with users not having freed some interrupts, we'll end up leaking resources as indicated by the following warning: remove_proc_entry: removing non-empty directory 'irq/30', leaking at least 'gpio' As there's no way of notifying interrupt users about the irqchip going away and the interrupt subsystem is not plugged into the driver model and so not all cases can be handled by devlinks, we need to make sure to free all interrupts before the complete the removal of the provider. Reviewed-by: Herve Codina <herve.codina@bootlin.com> Tested-by: Herve Codina <herve.codina@bootlin.com> Link: https://lore.kernel.org/r/20240919135104.3583-1-brgl@bgdev.pl Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2024-09-02gpiolib: Update the kernel documentation - add Return sectionsAndy Shevchenko
$ scripts/kernel-doc -v -none -Wall drivers/gpio/gpiolib* 2>&1 | grep -w warning | wc -l 67 Fix these by adding Return sections. While at it, make sure all of Return sections use the same style. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Randy Dunlap <rdunlap@infradead.org> Tested-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20240828164449.2777666-1-andriy.shevchenko@linux.intel.com Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2024-09-02gpio: Use IS_ERR_OR_NULL() helper functionHongbo Li
Use the IS_ERR_OR_NULL() helper instead of open-coding a NULL and an error pointer checks to simplify the code and improve readability. No functional changes are intended. Signed-off-by: Hongbo Li <lihongbo22@huawei.com> Link: https://lore.kernel.org/r/20240828122039.3697037-1-lihongbo22@huawei.com Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2024-08-20gpiolib: Replace gpio_suffix_count with NULL-terminated arrayAndy Shevchenko
There is no need to have and export the count variable for the array in question. Instead, make it NULL-terminated. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20240819142945.327808-6-andriy.shevchenko@linux.intel.com Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2024-07-25Merge tag 'driver-core-6.11-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core Pull driver core updates from Greg KH: "Here is the big set of driver core changes for 6.11-rc1. Lots of stuff in here, with not a huge diffstat, but apis are evolving which required lots of files to be touched. Highlights of the changes in here are: - platform remove callback api final fixups (Uwe took many releases to get here, finally!) - Rust bindings for basic firmware apis and initial driver-core interactions. It's not all that useful for a "write a whole driver in rust" type of thing, but the firmware bindings do help out the phy rust drivers, and the driver core bindings give a solid base on which others can start their work. There is still a long way to go here before we have a multitude of rust drivers being added, but it's a great first step. - driver core const api changes. This reached across all bus types, and there are some fix-ups for some not-common bus types that linux-next and 0-day testing shook out. This work is being done to help make the rust bindings more safe, as well as the C code, moving toward the end-goal of allowing us to put driver structures into read-only memory. We aren't there yet, but are getting closer. - minor devres cleanups and fixes found by code inspection - arch_topology minor changes - other minor driver core cleanups All of these have been in linux-next for a very long time with no reported problems" * tag 'driver-core-6.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (55 commits) ARM: sa1100: make match function take a const pointer sysfs/cpu: Make crash_hotplug attribute world-readable dio: Have dio_bus_match() callback take a const * zorro: make match function take a const pointer driver core: module: make module_[add|remove]_driver take a const * driver core: make driver_find_device() take a const * driver core: make driver_[create|remove]_file take a const * firmware_loader: fix soundness issue in `request_internal` firmware_loader: annotate doctests as `no_run` devres: Correct code style for functions that return a pointer type devres: Initialize an uninitialized struct member devres: Fix memory leakage caused by driver API devm_free_percpu() devres: Fix devm_krealloc() wasting memory driver core: platform: Switch to use kmemdup_array() driver core: have match() callback in struct bus_type take a const * MAINTAINERS: add Rust device abstractions to DRIVER CORE device: rust: improve safety comments MAINTAINERS: add Danilo as FIRMWARE LOADER maintainer MAINTAINERS: add Rust FW abstractions to FIRMWARE LOADER firmware: rust: improve safety comments ...
2024-07-03driver core: have match() callback in struct bus_type take a const *Greg Kroah-Hartman
In the match() callback, the struct device_driver * should not be changed, so change the function callback to be a const *. This is one step of many towards making the driver core safe to have struct device_driver in read-only memory. Because the match() callback is in all busses, all busses are modified to handle this properly. This does entail switching some container_of() calls to container_of_const() to properly handle the constant *. For some busses, like PCI and USB and HV, the const * is cast away in the match callback as those busses do want to modify those structures at this point in time (they have a local lock in the driver structure.) That will have to be changed in the future if they wish to have their struct device * in read-only-memory. Cc: Rafael J. Wysocki <rafael@kernel.org> Reviewed-by: Alex Elder <elder@kernel.org> Acked-by: Sumit Garg <sumit.garg@linaro.org> Link: https://lore.kernel.org/r/2024070136-wrongdoer-busily-01e8@gregkh Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-07-02gpiolib: unexport gpiochip_get_desc()Bartosz Golaszewski
This function has been deprecated for some time and is now only used within the GPIOLIB core. Remove it from the public header and unexport it as all current users are linked against the compilation unit where it is defined. Link: https://lore.kernel.org/r/20240625073815.12376-1-brgl@bgdev.pl Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2024-06-14gpiolib: put gpio_suffixes in a single compilation unitBartosz Golaszewski
The gpio_suffixes array is defined in the gpiolib.h header. This means the array is stored in .rodata of every compilation unit that includes it. Put the definition for the array in gpiolib.c and export just the symbol in the header. We need the size of the array so expose it too. Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Link: https://lore.kernel.org/r/20240612184821.58053-1-brgl@bgdev.pl Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2024-06-04gpiolib: Show more info for interrupt only lines in debugfsAndy Shevchenko
Show more info for interrupt only lines in debugfs. It's useful to monitor the lines that have been never requested as GPIOs, but IRQs. Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20240530191418.1138003-3-andriy.shevchenko@linux.intel.com Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2024-06-04gpiolib: Return label, if set, for IRQ only lineAndy Shevchenko
If line has been locked as IRQ without requesting, still check its label and return it, if not NULL. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20240530191418.1138003-2-andriy.shevchenko@linux.intel.com Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2024-06-03gpiolib: make gpiochip_set_desc_names() return voidBartosz Golaszewski
gpiochip_set_desc_names() cannot fail so drop its return value. Link: https://lore.kernel.org/r/20240527194613.197810-1-brgl@bgdev.pl Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2024-05-27gpio: prevent potential speculation leaks in gpio_device_get_desc()Hagar Hemdan
Userspace may trigger a speculative read of an address outside the gpio descriptor array. Users can do that by calling gpio_ioctl() with an offset out of range. Offset is copied from user and then used as an array index to get the gpio descriptor without sanitization in gpio_device_get_desc(). This change ensures that the offset is sanitized by using array_index_nospec() to mitigate any possibility of speculative information leaks. This bug was discovered and resolved using Coverity Static Analysis Security Testing (SAST) by Synopsys, Inc. Signed-off-by: Hagar Hemdan <hagarhem@amazon.com> Link: https://lore.kernel.org/r/20240523085332.1801-1-hagarhem@amazon.com Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2024-05-14Merge tag 'gpio-updates-for-v6.10-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux Pull gpio updates from Bartosz Golaszewski "This was a quiet release cycle for the GPIO tree and so this pull-request is relatively small. We have one new driver, some minor improvements to the GPIO core code and across several drivers, some DT and documentation updates but in general nothing stands out or is controversial. All changes have spent time in next with no reported issues (or ones that were quickly fixed). GPIO core: - remove more unused legacy interfaces (after converting the last remaining users to better alternatives) - update kerneldocs - improve error handling and log messages in GPIO ACPI code - remove dead code (always true checks) from GPIOLIB New drivers: - add a driver for Intel Granite Rapids-D vGPIO Driver improvements: - use -ENOTSUPP consistently in gpio-regmap and gpio-pcie-idio-24 - provide an ID table for gpio-cros-ec to avoid a driver name fallback check - add support for gpio-ranges for GPIO drivers supporting multiple GPIO banks - switch to using dynamic GPIO base in gpio-brcmstb - fix irq handling in gpio-npcm-sgpio - switch to memory mapped IO accessors in gpio-sch DT bindings: - add support for gpio-ranges to gpio-brcmstb - add support for a new model and the gpio-line-names property to gpio-mpfs Documentation: - replace leading tabs with spaces in code blocks - fix typos" * tag 'gpio-updates-for-v6.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux: (30 commits) gpio: nuvoton: Fix sgpio irq handle error gpiolib: Discourage to use formatting strings in line names gpio: brcmstb: add support for gpio-ranges gpio: of: support gpio-ranges for multiple gpiochip devices dt-bindings: gpio: brcmstb: add gpio-ranges gpio: Add Intel Granite Rapids-D vGPIO driver gpio: brcmstb: Use dynamic GPIO base numbers gpiolib: acpi: Set label for IRQ only lines gpiolib: acpi: Add fwnode name to the GPIO interrupt label gpiolib: Get rid of never false gpio_is_valid() calls gpiolib: acpi: Pass con_id instead of property into acpi_dev_gpio_irq_get_by() gpiolib: acpi: Move acpi_can_fallback_to_crs() out of __acpi_find_gpio() gpiolib: acpi: Simplify error handling in __acpi_find_gpio() gpiolib: acpi: Extract __acpi_find_gpio() helper gpio: sch: Utilise temporary variable for struct device gpio: sch: Switch to memory mapped IO accessors gpio: regmap: Use -ENOTSUPP consistently gpio: pcie-idio-24: Use -ENOTSUPP consistently Documentation: gpio: Replace leading TABs by spaces in code blocks gpiolib: acpi: Check for errors first in acpi_find_gpio() ...
2024-05-09gpiolib: use a single SRCU struct for all GPIO descriptorsBartosz Golaszewski
We used a per-descriptor SRCU struct in order to not impose a wait with synchronize_srcu() for descriptor X on read-only operations of descriptor Y. Now that we no longer call synchronize_srcu() on descriptor label change but only when releasing descriptor resources, we can use a single SRCU structure for all GPIO descriptors in a given chip. Suggested-by: "Paul E. McKenney" <paulmck@kernel.org> Acked-by: "Paul E. McKenney" <paulmck@kernel.org> Link: https://lore.kernel.org/r/20240507172414.28513-1-brgl@bgdev.pl Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2024-05-07gpiolib: fix the speed of descriptor label setting with SRCUBartosz Golaszewski
Commit 1f2bcb8c8ccd ("gpio: protect the descriptor label with SRCU") caused a massive drop in performance of requesting GPIO lines due to the call to synchronize_srcu() on each label change. Rework the code to not wait until all read-only users are done with reading the label but instead atomically replace the label pointer and schedule its release after all read-only critical sections are done. To that end wrap the descriptor label in a struct that also contains the rcu_head struct required for deferring tasks using call_srcu() and stop using kstrdup_const() as we're required to allocate memory anyway. Just allocate enough for the label string and rcu_head in one go. Reported-by: Neil Armstrong <neil.armstrong@linaro.org> Closes: https://lore.kernel.org/linux-gpio/CAMRc=Mfig2oooDQYTqo23W3PXSdzhVO4p=G4+P8y1ppBOrkrJQ@mail.gmail.com/ Fixes: 1f2bcb8c8ccd ("gpio: protect the descriptor label with SRCU") Suggested-by: "Paul E. McKenney" <paulmck@kernel.org> Tested-by: Neil Armstrong <neil.armstrong@linaro.org> # on SM8650-QRD Acked-by: "Paul E. McKenney" <paulmck@kernel.org> Link: https://lore.kernel.org/r/20240507121346.16969-1-brgl@bgdev.pl Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2024-04-17gpiolib: Get rid of never false gpio_is_valid() callsAndy Shevchenko
In the cases when gpio_is_valid() is called with unsigned parameter the result is always true in the GPIO library code, hence the check for false won't ever be true. Get rid of such calls. While at it, move GPIO device base to be unsigned to clearly show it won't ever be negative. This requires a new definition for the maximum GPIO number in the system. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2024-04-03gpiolib: Do not mention legacy GPIOF_* in the codeAndy Shevchenko
We are going to remove legacy API from kernel, don't mention it in the code that does not use it already for a while. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2024-04-03gpiolib: Fix triggering "kobject: 'gpiochipX' is not initialized, yet" ↵Hans de Goede
kobject_get() errors When a gpiochip gets added by loading a module, then another driver may be waiting for that gpiochip to load on the deferred-probe list. If the deferred-probe for the consumer of gpiochip then triggers between the gpiodev_add_to_list_unlocked() calls which makes gpio_device_find() see the chip and the gpiochip_setup_dev() later then gpio_device_find() does a kobject_get() on an uninitialized kobject since the kobject is initialized by gpiochip_setup_dev() calling device_initialize(): arizona spi-10WM5102:00: cannot find GPIO chip arizona, deferring arizona spi-10WM5102:00: cannot find GPIO chip arizona, deferring ------------[ cut here ]------------ kobject: 'gpiochip5' (00000000241466f2): is not initialized, yet kobject_get() is being called. WARNING: CPU: 3 PID: 42 at lib/kobject.c:640 kobject_get+0x43/0x70 Call Trace: kobject_get gpio_device_find gpiod_find_and_request gpiod_get snd_byt_wm5102_mc_probe Not only is the device not initialized yet, but when the gpio-device is added to the list things like the irqchip also have not been initialized yet. So gpio_device_find() should really ignore the gpio-device until gpiochip_add_data_with_key() is fully done. Add a device_is_registered() check to gpio_device_find() to ignore gpio-devices on the list which are not yet fully initialized. Fixes: aab5c6f20023 ("gpio: set device type for GPIO chips") Suggested-by: Bartosz Golaszewski <brgl@bgdev.pl> Signed-off-by: Hans de Goede <hdegoede@redhat.com> Reviewed-by: Andy Shevchenko <andy@kernel.org> [Bartosz: fix a typo in commit message] Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2024-04-02gpiolib: use dev_err() when gpiod_configure_flags failedPeng Fan
When gpio-ranges property was missed to be added in the gpio node, using dev_err() to show an error message will helping to locate issues easier. Signed-off-by: Peng Fan <peng.fan@nxp.com> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2024-03-26gpiolib: Fix debug messaging in gpiod_find_and_request()Andy Shevchenko
When consolidating GPIO lookups in ACPI code, the debug messaging had been reworked that the user may see [ 13.401147] (NULL device *): using ACPI '\_SB.LEDS.led-0' for '(null)' GPIO lookup [ 13.401378] gpio gpiochip0: Persistence not supported for GPIO 40 [ 13.401402] gpio-40 (?): no flags found for (null) instead of [ 14.182962] gpio gpiochip0: Persistence not supported for GPIO 40 [ 14.182994] gpio-40 (?): no flags found for gpios The '(null)' parts are less informative and likely scare the users. Replace them by '(default)' which can point out to the default connection IDs, such as 'gpios'. While at it, amend other places where con_id is used in the messages. Reported-by: Ferry Toth <ftoth@exalondelft.nl> Fixes: 8eb1f71e7acc ("gpiolib: consolidate GPIO lookups") Suggested-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Tested-by: Ferry Toth <ftoth@exalondelft.nl> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2024-03-05gpiolib: Deduplicate cleanup for-loop in gpiochip_add_data_with_key()Andy Shevchenko
There is no need to repeat for-loop twice in the error path in gpiochip_add_data_with_key(). Deduplicate it. While at it, rename loop variable to be more specific and avoid ambguity. It also properly unwinds the SRCU, i.e. in reversed order of allocating. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2024-03-05Merge tag 'v6.8-rc7' into gpio/for-nextBartosz Golaszewski
Linux 6.8-rc7
2024-03-01gpio: fix resource unwinding order in error pathBartosz Golaszewski
Hogs are added *after* ACPI so should be removed *before* in error path. Fixes: a411e81e61df ("gpiolib: add hogs support for machine code") Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
2024-03-01gpio: acpi: Make acpi_gpio_count() take firmware node as a parameterAndy Shevchenko
Make acpi_gpio_count() take firmware node as a parameter in order to be aligned with other functions and decouple from unused device pointer. The latter helps to create a common fwnode_gpio_count() in the future. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2024-03-01gpio: of: Make of_gpio_get_count() take firmware node as a parameterAndy Shevchenko
Make of_gpio_get_count() take firmware node as a parameter in order to be aligned with other functions and decouple from unused device pointer. The latter helps to create a common fwnode_gpio_count() in the future. While at it, rename to be of_gpio_count() to be aligned with the others. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2024-03-01gpiolib: Fix the error path order in gpiochip_add_data_with_key()Andy Shevchenko
After shuffling the code, error path wasn't updated correctly. Fix it here. Fixes: 2f4133bb5f14 ("gpiolib: No need to call gpiochip_remove_pin_ranges() twice") Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2024-02-27gpiolib: Pass consumer device through to core in devm_fwnode_gpiod_get_index()Stephen Boyd
This devm API takes a consumer device as an argument to setup the devm action, but throws it away when calling further into gpiolib. This leads to odd debug messages like this: (NULL device *): using DT '/gpio-keys/switch-pen-insert' for '(null)' GPIO lookup Let's pass the consumer device down, by directly calling what fwnode_gpiod_get_index() calls but pass the device used for devm. This changes the message to look like this instead: gpio-keys gpio-keys: using DT '/gpio-keys/switch-pen-insert' for '(null)' GPIO lookup Note that callers of fwnode_gpiod_get_index() will still see the NULL device pointer debug message, but there's not much we can do about that because the API doesn't take a struct device. Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com> Fixes: 8eb1f71e7acc ("gpiolib: consolidate GPIO lookups") Signed-off-by: Stephen Boyd <swboyd@chromium.org> Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2024-02-26gpio: don't warn about removing GPIO chips with active users anymoreBartosz Golaszewski
With SRCU we can now correctly handle the situation when a GPIO provider is removed while having users still holding references to GPIO descriptors. Remove all warnings emitted in this situation. Suggested-by: Kent Gibson <warthog618@gmail.com> Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org> Reviewed-by: Herve Codina <herve.codina@bootlin.com>
2024-02-20gpiolib: Handle no pin_ranges in gpiochip_generic_config()Emil Renner Berthing
Similar to gpiochip_generic_request() and gpiochip_generic_free() the gpiochip_generic_config() function needs to handle the case where there are no pinctrl pins mapped to the GPIOs, usually through the gpio-ranges device tree property. Commit f34fd6ee1be8 ("gpio: dwapb: Use generic request, free and set_config") set the .set_config callback to gpiochip_generic_config() in the dwapb GPIO driver so the GPIO API can set pinctrl configuration for the corresponding pins. Most boards using the dwapb driver do not set the gpio-ranges device tree property though, and in this case gpiochip_generic_config() would return -EPROPE_DEFER rather than the previous -ENOTSUPP return value. This in turn makes gpio_set_config_with_argument_optional() fail and propagate the error to any driver requesting GPIOs. Fixes: 2956b5d94a76 ("pinctrl / gpio: Introduce .set_config() callback for GPIO chips") Reported-by: Jisheng Zhang <jszhang@kernel.org> Closes: https://lore.kernel.org/linux-gpio/ZdC_g3U4l0CJIWzh@xhacker/ Tested-by: Jisheng Zhang <jszhang@kernel.org> Signed-off-by: Emil Renner Berthing <emil.renner.berthing@canonical.com> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2024-02-19gpio: fix memory leak in gpiod_request_commit()Xiaolei Wang
Since commit 1f2bcb8c8ccd ("gpio: protect the descriptor label with SRCU"), desc_set_label() already allocates memory for the label, so there is no need to allocate it again. If we do, we leak it. unreferenced object 0xffff0000c3e4d0c0 (size 32): comm "kworker/u16:4", pid 60, jiffies 4294894555 hex dump (first 32 bytes): 72 65 67 75 6c 61 74 6f 72 2d 63 61 6e 32 2d 73 regulator-can2-s 74 62 79 00 00 00 ff ff ff ff ff ff eb db ff ff tby............. backtrace (crc 2c3a0350): [<00000000e93c5cf4>] kmemleak_alloc+0x34/0x40 [<0000000097a2657f>] __kmalloc_node_track_caller+0x2c4/0x524 [<000000000dd1c057>] kstrdup+0x4c/0x98 [<00000000b513a96a>] kstrdup_const+0x34/0x40 [<000000008a7f0feb>] gpiod_request_commit+0xdc/0x358 [<00000000fc71ad64>] gpiod_request+0xd8/0x204 [<00000000fa24b091>] gpiod_find_and_request+0x170/0x780 [<0000000086ecf92d>] gpiod_get_index+0x70/0xe0 [<000000004aef97f9>] gpiod_get_optional+0x18/0x30 [<00000000312f1b25>] reg_fixed_voltage_probe+0x58c/0xad8 [<00000000e6f47635>] platform_probe+0xc4/0x198 [<00000000cf78fbdb>] really_probe+0x204/0x5a8 [<00000000e28d05ec>] __driver_probe_device+0x158/0x2c4 [<00000000e4fe452b>] driver_probe_device+0x60/0x18c [<00000000479fcf5d>] __device_attach_driver+0x168/0x208 [<000000007d389f38>] bus_for_each_drv+0x104/0x190 Fixes: 1f2bcb8c8ccd ("gpio: protect the descriptor label with SRCU") Signed-off-by: Xiaolei Wang <xiaolei.wang@windriver.com> [Bartosz: tweaked the commit message] Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2024-02-17gpio: constify opaque pointer "data" in gpio_device_find()Krzysztof Kozlowski
The opaque pointer "data" in each match function used by gpio_device_find() is a pointer to const, thus the same argument passed to gpio_device_find() can adjusted similarly. Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org> Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2024-02-15gpio: don't let lockdep complain about inherently dangerous RCU usageBartosz Golaszewski
There are two legacy, deprecated functions - gpiod_to_chip() and gpio_device_get_chip() - that still have users in tree. They return the address of the SRCU-protected chip outside of the read-only critical sections. They are inherently dangerous and the users should convert to safer alternatives. Let's explicitly silence lockdep warnings by using rcu_dereference_check(ptr, 1). While at it: reuse gpio_device_get_chip() in gpiod_to_chip(). Fixes: d83cee3d2bb1 ("gpio: protect the pointer to gpio_chip in gpio_device with SRCU") Reported-by: kernel test robot <oliver.sang@intel.com> Closes: https://lore.kernel.org/oe-lkp/202402122234.d85cca9b-lkp@intel.com Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2024-02-15gpio: use srcu_dereference() with SRCU-protected pointersBartosz Golaszewski
Lockdep with CONFIG_PROVE_RCU enabled reports false positives about suspicious rcu_dereference() usage. Let's silence it by using srcu_dereference() which is the correct helper with SRCU. Fixes: d83cee3d2bb1 ("gpio: protect the pointer to gpio_chip in gpio_device with SRCU") Reported-by: kernel test robot <oliver.sang@intel.com> Closes: https://lore.kernel.org/oe-lkp/202402122234.d85cca9b-lkp@intel.com Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org> Acked-by: Paul E. McKenney <paulmck@kernel.org>
2024-02-15gpio: take the SRCU read lock in gpiod_hog()Bartosz Golaszewski
gpiod_hog() may be called without the gpio_device SRCU read lock taken so we need to do it here as well. It's alright if someone else is already holding the lock as SRCU read critical sections can be nested. Fixes: d83cee3d2bb1 ("gpio: protect the pointer to gpio_chip in gpio_device with SRCU") Reported-by: kernel test robot <oliver.sang@intel.com> Closes: https://lore.kernel.org/oe-lkp/202402122234.d85cca9b-lkp@intel.com Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Acked-by: Paul E. McKenney <paulmck@kernel.org>
2024-02-14gpio: initialize descriptor SRCU structure before adding OF-based chipsBartosz Golaszewski
In certain situations we may end up taking the GPIO descriptor SRCU read lock in of_gpiochip_add() before the SRCU struct is initialized. Move the initialization before the call to of_gpiochip_add(). Fixes: be711caa87c5 ("gpio: add SRCU infrastructure to struct gpio_desc") Fixes: 1f2bcb8c8ccd ("gpio: protect the descriptor label with SRCU") Reported-by: kernel test robot <lkp@intel.com> Closes: https://lore.kernel.org/oe-lkp/202402122228.e607a080-lkp@intel.com Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>