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* gpio: cdev: fix missed label sanitizing in debounce_setup()Kent Gibson2024-04-041-21/+28
| | | | | | | | | | | | | | | | | When adding sanitization of the label, the path through edge_detector_setup() that leads to debounce_setup() was overlooked. A request taking this path does not allocate a new label and the request label is freed twice when the request is released, resulting in memory corruption. Add label sanitization to debounce_setup(). Cc: stable@vger.kernel.org Fixes: b34490879baa ("gpio: cdev: sanitize the label before requesting the interrupt") Signed-off-by: Kent Gibson <warthog618@gmail.com> [Bartosz: rebased on top of the fix for empty GPIO labels] Co-developed-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org> Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
* gpio: cdev: check for NULL labels when sanitizing them for irqsBartosz Golaszewski2024-04-041-5/+14
| | | | | | | | | | | | | | | | We need to take into account that a line's consumer label may be NULL and not try to kstrdup() it in that case but rather pass the NULL pointer up the stack to the interrupt request function. To that end: let make_irq_label() return NULL as a valid return value and use ERR_PTR() instead to signal an allocation failure to callers. Cc: stable@vger.kernel.org Fixes: b34490879baa ("gpio: cdev: sanitize the label before requesting the interrupt") Reported-by: Linux Kernel Functional Testing <lkft@linaro.org> Closes: https://lore.kernel.org/lkml/20240402093534.212283-1-naresh.kamboju@linaro.org/ Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org> Tested-by: Anders Roxell <anders.roxell@linaro.org>
* gpio: cdev: sanitize the label before requesting the interruptBartosz Golaszewski2024-03-261-6/+32
| | | | | | | | | | | | | | | | | | | | When an interrupt is requested, a procfs directory is created under "/proc/irq/<irqnum>/<label>" where <label> is the string passed to one of the request_irq() variants. What follows is that the string must not contain the "/" character or the procfs mkdir operation will fail. We don't have such constraints for GPIO consumer labels which are used verbatim as interrupt labels for GPIO irqs. We must therefore sanitize the consumer string before requesting the interrupt. Let's replace all "/" with ":". Cc: stable@vger.kernel.org Reported-by: Stefan Wahren <wahrenst@gmx.net> Closes: https://lore.kernel.org/linux-gpio/39fe95cb-aa83-4b8b-8cab-63947a726754@gmx.net/ Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org> Reviewed-by: Kent Gibson <warthog618@gmail.com>
* gpio: cdev: fix a NULL-pointer dereference with DEBUG enabledBartosz Golaszewski2024-02-161-2/+2
| | | | | | | | | | | We are actually passing the gc pointer to chip_dbg() so we have to srcu_dereference() it. Fixes: 8574b5b47610 ("gpio: cdev: use correct pointer accessors with SRCU") Reported-by: Marek Szyprowski <m.szyprowski@samsung.com> Closes: https://lore.kernel.org/lkml/179caa10-5f86-4707-8bb0-fe1b316326d6@samsung.com/ Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org> Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
* gpio: cdev: use correct pointer accessors with SRCUBartosz Golaszewski2024-02-151-13/+12
| | | | | | | | | | | | | | We never dereference the chip pointer in character device code so we can use the lighter rcu_access_pointer() helper. This also makes lockep happier as it no longer complains about suspicious rcu_dereference() usage. 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>
* gpio: protect the pointer to gpio_chip in gpio_device with SRCUBartosz Golaszewski2024-02-121-28/+36
| | | | | | | | | | | | | | | | | | | Ensure we cannot crash if the GPIO device gets unregistered (and the chip pointer set to NULL) during any of the API calls. To that end: wait for all users of gdev->chip to exit their read-only SRCU critical sections in gpiochip_remove(). For brevity: add a guard class which can be instantiated at the top of every function requiring read-only access to the chip pointer and use it in all API calls taking a GPIO descriptor as argument. In places where we only deal with the GPIO device - use regular guard() helpers and rcu_dereference() for chip access. Do the same in API calls taking a const pointer to gpio_desc. Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
* gpio: cdev: don't access gdev->chip if it's not neededBartosz Golaszewski2024-02-121-1/+1
| | | | | | | | | | The variable holding the number of GPIO lines is duplicated in GPIO device so read it instead of unnecessarily dereferencing the chip pointer. Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
* gpio: cdev: replace gpiochip_get_desc() with gpio_device_get_desc()Bartosz Golaszewski2024-02-121-5/+5
| | | | | | | | | | gpio_device_get_desc() is the safer alternative to gpiochip_get_desc(). As we don't really need to dereference the chip pointer to retrieve the descriptors in character device code, let's use it. Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
* gpio: remove gpio_lockBartosz Golaszewski2024-02-121-11/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The "multi-function" gpio_lock is pretty much useless with how it's used in GPIOLIB currently. Because many GPIO API calls can be called from all contexts but may also call into sleeping driver callbacks, there are many places with utterly broken workarounds like yielding the lock to call a possibly sleeping function and then re-acquiring it again without taking into account that the protected state may have changed. It was also used to protect several unrelated things: like individual descriptors AND the GPIO device list. We now serialize access to these two with SRCU and so can finally remove the spinlock. There is of course the question of consistency of lockless access to GPIO descriptors. Because we only support exclusive access to GPIOs (officially anyway, I'm looking at you broken GPIOD_FLAGS_BIT_NONEXCLUSIVE bit...) and the API contract with providers does not guarantee serialization, it's enough to ensure we cannot accidentally dereference an invalid pointer and that the state we present to both users and providers remains consistent. To achieve that: read the flags field atomically except for a few special cases. Read their current value before executing callback code and use this value for any subsequent logic. Modifying the flags depends on the particular use-case and can differ. For instance: when requesting a GPIO, we need to set the REQUESTED bit immediately so that the next user trying to request the same line sees -EBUSY. While at it: the allocations that used GFP_ATOMIC until this point can now switch to GFP_KERNEL. Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
* gpio: protect the descriptor label with SRCUBartosz Golaszewski2024-02-121-3/+7
| | | | | | | | | | | | | In order to ensure that the label is not freed while it's being accessed, let's protect it with SRCU and synchronize it everytime it's changed. Let's modify desc_set_label() to manage the memory used for the label as it can only be freed once synchronize_srcu() returns. Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
* gpio: provide and use gpiod_get_label()Bartosz Golaszewski2024-02-121-2/+2
| | | | | | | | | | | | | | | | | | We will soon serialize access to the descriptor label using SRCU. The write-side of the protection will require calling synchronize_srcu() which must not be called from atomic context. We have two irq helpers: gpiochip_lock_as_irq() and gpiochip_unlock_as_irq() that set the label if the GPIO is not requested but is being used as interrupt. They are called with a spinlock held from the interrupt subsystem. They must not do it if we are to use SRCU so instead let's move the special corner case to a dedicated getter. First: let's implement and use the getter where it's applicable. Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
* gpio: cdev: remove leftover function pointer typedefsBartosz Golaszewski2024-01-291-5/+0
| | | | | | | | The locking wrappers were replaces with lock guards. These typedefs are no longer needed. Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org> Reviewed-by: Kent Gibson <warthog618@gmail.com>
* gpiolib: cdev: replace locking wrappers for gpio_device with guardsKent Gibson2023-12-271-158/+47
| | | | | | | | Replace the wrapping functions that inhibit removal of the gpio chip with equivalent guards. Signed-off-by: Kent Gibson <warthog618@gmail.com> Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
* gpiolib: cdev: replace locking wrappers for config_mutex with guardsKent Gibson2023-12-271-39/+24
| | | | | | | | | After the adoption of guard(), the locking wrappers that hold the config_mutex for linereq_set_values() and linereq_set_config() no longer add value, so combine them into the functions they wrap. Signed-off-by: Kent Gibson <warthog618@gmail.com> Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
* gpiolib: cdev: allocate linereq using kvzalloc()Kent Gibson2023-12-271-2/+2
| | | | | | | | | | The size of struct linereq may exceed a page, so allocate space for it using kvzalloc() instead of kzalloc() to handle the case where memory is heavily fragmented and kzalloc() cannot find a sufficient contiguous region. Signed-off-by: Kent Gibson <warthog618@gmail.com> Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
* gpiolib: cdev: include overflow.hKent Gibson2023-12-271-0/+1
| | | | | | | | struct_size() is used to calculate struct linereq size, so explicitly include overflow.h. Signed-off-by: Kent Gibson <warthog618@gmail.com> Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
* Merge tag 'v6.7-rc7' into gpio/for-nextBartosz Golaszewski2023-12-271-4/+12
|\ | | | | | | Linux 6.7-rc7
| * gpiolib: cdev: add gpio_device locking wrapper around gpio_ioctl()Kent Gibson2023-12-211-4/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | While the GPIO cdev gpio_ioctl() call is in progress, the kernel can call gpiochip_remove() which will set gdev->chip to NULL, after which any subsequent access will cause a crash. gpio_ioctl() was overlooked by the previous fix to protect syscalls (bdbbae241a04), so add protection for that. Fixes: bdbbae241a04 ("gpiolib: protect the GPIO device against being dropped while in use by user-space") Fixes: d7c51b47ac11 ("gpio: userspace ABI for reading/writing GPIO lines") Fixes: 3c0d9c635ae2 ("gpiolib: cdev: support GPIO_V2_GET_LINE_IOCTL and GPIO_V2_LINE_GET_VALUES_IOCTL") Fixes: aad955842d1c ("gpiolib: cdev: support GPIO_V2_GET_LINEINFO_IOCTL and GPIO_V2_GET_LINEINFO_WATCH_IOCTL") Signed-off-by: Kent Gibson <warthog618@gmail.com> Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
* | gpiolib: cdev: reduce locking in gpio_desc_to_lineinfo()Kent Gibson2023-12-191-38/+36
| | | | | | | | | | | | | | | | | | | | | | | | | | Reduce the time holding the gpio_lock by snapshotting the desc flags, rather than testing them individually while holding the lock. Accept that the calculation of the used field is inherently racy, and only check the availability of the line from pinctrl if other checks pass, so avoiding the check for lines that are otherwise in use. Signed-off-by: Kent Gibson <warthog618@gmail.com> Reviewed-by: Andy Shevchenko <andy@kernel.org> Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
* | gpiolib: cdev: improve documentation of get/set valuesKent Gibson2023-12-191-1/+23
| | | | | | | | | | | | | | | | | | | | Add documentation of the algorithm used to perform scatter/gather of the requested lines and values in linereq_get_values() and linereq_set_values_unlocked() to improve maintainability. Signed-off-by: Kent Gibson <warthog618@gmail.com> Reviewed-by: Andy Shevchenko <andy@kernel.org> Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
* | gpiolib: cdev: fully adopt guard() and scoped_guard()Kent Gibson2023-12-191-86/+57
| | | | | | | | | | | | | | | | | | Use guard() or scoped_guard() for critical sections rather than discrete lock/unlock pairs. Signed-off-by: Kent Gibson <warthog618@gmail.com> Reviewed-by: Andy Shevchenko <andy@kernel.org> Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
* | gpiolib: cdev: relocate debounce_period_us from struct gpio_descKent Gibson2023-12-191-23/+142
|/ | | | | | | | | | | | | Store the debounce period for a requested line locally, rather than in the debounce_period_us field in the gpiolib struct gpio_desc. Add a global tree of lines containing supplemental line information to make the debounce period available to be reported by the GPIO_V2_GET_LINEINFO_IOCTL and the line change notifier. Signed-off-by: Kent Gibson <warthog618@gmail.com> Reviewed-by: Andy Shevchenko <andy@kernel.org> Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
* treewide: rename pinctrl_gpio_can_use_line_new()Bartosz Golaszewski2023-11-041-1/+1
| | | | | | | | Now that pinctrl_gpio_can_use_line() is no longer used, let's drop the '_new' suffix from its improved variant. Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org> Acked-by: Linus Walleij <linus.walleij@linaro.org>
* gpio: cdev: use pinctrl_gpio_can_use_line_new()Bartosz Golaszewski2023-11-041-2/+1
| | | | | | | | | Use the improved variant of pinctrl_gpio_can_use_line() which takes a pointer to the gpio_chip and a controller-relative offset. Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Linus Walleij <linus.walleij@linaro.org>
* gpiolib: cdev: annotate struct linereq with __counted_byKees Cook2023-09-251-2/+2
| | | | | | | | | | | | | | | | | | | | Prepare for the coming implementation by GCC and Clang of the __counted_by attribute. Flexible array members annotated with __counted_by can have their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS (for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family functions). As found with Coccinelle[1], add __counted_by for struct linereq. Additionally, since the element count member must be set before accessing the annotated flexible array member, move its initialization earlier. [1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci Signed-off-by: Kees Cook <keescook@chromium.org> Reviewed-by: Gustavo A. R. Silva <gustavoars@kernel.org> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Reviewed-by: Andy Shevchenko <andy@kernel.org> Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
* gpiolib: provide and use gpiod_line_state_notify()Bartosz Golaszewski2023-08-221-12/+5
| | | | | | | | | Wrap the calls to blocking_notifier_call_chain() for the line state notifier with a helper that allows us to use fewer lines of code and simpler syntax. Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
* gpio: cdev: wake up lineevent poll() on device unbindBartosz Golaszewski2023-08-211-0/+22
| | | | | | | | | | | | Add a notifier block to the lineevent_state structure and register it with the gpio_device's device notifier. Upon reception of an event, wake up the wait queue so that the user-space be forced out of poll() and need to go into a new system call which will then fail due to the chip being gone. Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Reviewed-by: Kent Gibson <warthog618@gmail.com>
* gpio: cdev: wake up linereq poll() on device unbindBartosz Golaszewski2023-08-211-0/+23
| | | | | | | | | | | Add a notifier block to the linereq structure and register it with the gpio_device's device notifier. Upon reception of an event, wake up the wait queue so that the user-space be forced out of poll() and need to go into a new system call which will then fail due to the chip being gone. Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Reviewed-by: Kent Gibson <warthog618@gmail.com>
* gpio: cdev: wake up chardev poll() on device unbindBartosz Golaszewski2023-08-211-2/+27
| | | | | | | | | | | | Add a notifier block to the gpio_chardev_data structure and register it with the gpio_device's device notifier. Upon reception of an event, wake up the wait queue so that the user-space be forced out of poll() and need to go into a new system call which will then fail due to the chip being gone. Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Reviewed-by: Kent Gibson <warthog618@gmail.com>
* gpiolib: add a second blocking notifier to struct gpio_deviceBartosz Golaszewski2023-08-211-0/+1
| | | | | | | | | | Add a new blocking notifier to struct gpio_device and use it to notify subscribers about the GPIO device being unregistered from the device model. Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Reviewed-by: Kent Gibson <warthog618@gmail.com>
* gpio: cdev: open-code to_gpio_chardev_data()Bartosz Golaszewski2023-08-211-7/+2
| | | | | | | | | | This function is a wrapper around container_of(). It's used only once and we will have a second notifier soon, so instead of having two flavors of this helper, let's just open-code where needed. Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Reviewed-by: Kent Gibson <warthog618@gmail.com>
* gpiolib: rename the gpio_device notifierBartosz Golaszewski2023-08-211-8/+8
| | | | | | | | | | Change the generic "notifier" name to "line_state_notifier" in order to reflect its purpose in preparation for adding a second notifier which will be used to notify wait queues about device unregistering. Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Reviewed-by: Kent Gibson <warthog618@gmail.com>
* gpiolib: Introduce gpio_device_get() and gpio_device_put()Andy Shevchenko2023-01-301-12/+9
| | | | | | | | | Introduce gpio_device_get() and gpio_device_put() helpers and convert existing users. 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>
* Merge tag 'gpio-updates-for-v6.2' of ↵Linus Torvalds2022-12-151-26/+180
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux Pull gpio updates from Bartosz Golaszewski: "We have a new GPIO multiplexer driver, bunch of driver updates and refactoring in the core GPIO library. GPIO core: - teach gpiolib to work with software nodes for HW description - remove ARCH_NR_GPIOS treewide as we no longer impose any limit on the number of GPIOS since the allocation became entirely dynamic - add support for HW quirks for Cirrus CS42L56 codec, Marvell NFC controller, Freescale PCIe and Ethernet controller, Himax LCDs and Mediatek mt2701 - refactor OF quirk code - some general refactoring of the OF and ACPI code, adding new helpers, minor tweaks and fixes, making fwnode usage consistent etc. GPIO uAPI: - fix an issue where the user-space can trigger a NULL-pointer dereference in the kernel by opening a device file, forcing a driver unbind and then calling one of the syscalls on the associated file descriptor New drivers: - add gpio-latch: a new GPIO multiplexer based on latches connected to other GPIOs Driver updates: - convert i2c GPIO expanders to using .probe_new() - drop the gpio-sta2x11 driver - factor out common code for the ACCES IDIO-16 family of controllers and use this new library wherever applicable in drivers - add DT support to gpio-hisi - allow building gpio-davinci as a module and increase its maxItems property - add support for a new model to gpio-pca9570 - other minor changes to various drivers" * tag 'gpio-updates-for-v6.2' of git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux: (66 commits) gpio: sim: set a limit on the number of GPIOs gpiolib: protect the GPIO device against being dropped while in use by user-space gpiolib: cdev: fix NULL-pointer dereferences gpiolib: Provide to_gpio_device() helper gpiolib: Unify access to the device properties gpio: Do not include <linux/kernel.h> when not really needed. gpio: pcf857x: Convert to i2c's .probe_new() gpio: pca953x: Convert to i2c's .probe_new() gpio: max732x: Convert to i2c's .probe_new() dt-bindings: gpio: gpio-davinci: Increase maxItems in gpio-line-names gpiolib: ensure that fwnode is properly set gpio: sl28cpld: Replace irqchip mask_invert with unmask_base gpiolib: of: Use correct fwnode for DT-probed chips gpiolib: of: Drop redundant check in of_mm_gpiochip_remove() gpiolib: of: Prepare of_mm_gpiochip_add_data() for fwnode gpiolib: add support for software nodes gpiolib: consolidate GPIO lookups gpiolib: acpi: avoid leaking ACPI details into upper gpiolib layers gpiolib: acpi: teach acpi_find_gpio() to handle data-only nodes gpiolib: acpi: change acpi_find_gpio() to accept firmware node ...
| * gpiolib: protect the GPIO device against being dropped while in use by ↵Bartosz Golaszewski2022-12-071-25/+152
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | user-space While any of the GPIO cdev syscalls is in progress, the kernel can call gpiochip_remove() (for instance, when a USB GPIO expander is disconnected) which will set gdev->chip to NULL after which any subsequent access will cause a crash. To avoid that: use an RW-semaphore in which the syscalls take it for reading (so that we don't needlessly prohibit the user-space from calling syscalls simultaneously) while gpiochip_remove() takes it for writing so that it can only happen once all syscalls return. Fixes: d7c51b47ac11 ("gpio: userspace ABI for reading/writing GPIO lines") Fixes: 3c0d9c635ae2 ("gpiolib: cdev: support GPIO_V2_GET_LINE_IOCTL and GPIO_V2_LINE_GET_VALUES_IOCTL") Fixes: aad955842d1c ("gpiolib: cdev: support GPIO_V2_GET_LINEINFO_IOCTL and GPIO_V2_GET_LINEINFO_WATCH_IOCTL") Fixes: a54756cb24ea ("gpiolib: cdev: support GPIO_V2_LINE_SET_CONFIG_IOCTL") Fixes: 7b8e00d98168 ("gpiolib: cdev: support GPIO_V2_LINE_SET_VALUES_IOCTL") Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org> [Nick: fixed a build failure with CDEV_V1 disabled] Co-authored-by: Nick Hainke <vincent@systemli.org> Reviewed-by: Kent Gibson <warthog618@gmail.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
| * gpiolib: cdev: fix NULL-pointer dereferencesBartosz Golaszewski2022-12-071-0/+27
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There are several places where we can crash the kernel by requesting lines, unbinding the GPIO device, then calling any of the system calls relevant to the GPIO character device's annonymous file descriptors: ioctl(), read(), poll(). While I observed it with the GPIO simulator, it will also happen for any of the GPIO devices that can be hot-unplugged - for instance any HID GPIO expander (e.g. CP2112). This affects both v1 and v2 uAPI. This fixes it partially by checking if gdev->chip is not NULL but it doesn't entirely remedy the situation as we still have a race condition in which another thread can remove the device after the check. Fixes: d7c51b47ac11 ("gpio: userspace ABI for reading/writing GPIO lines") Fixes: 3c0d9c635ae2 ("gpiolib: cdev: support GPIO_V2_GET_LINE_IOCTL and GPIO_V2_LINE_GET_VALUES_IOCTL") Fixes: aad955842d1c ("gpiolib: cdev: support GPIO_V2_GET_LINEINFO_IOCTL and GPIO_V2_GET_LINEINFO_WATCH_IOCTL") Fixes: a54756cb24ea ("gpiolib: cdev: support GPIO_V2_LINE_SET_CONFIG_IOCTL") Fixes: 7b8e00d98168 ("gpiolib: cdev: support GPIO_V2_LINE_SET_VALUES_IOCTL") Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
| * gpiolib: cdev: Fix typo in kernel doc for struct lineAndy Shevchenko2022-10-251-1/+1
| | | | | | | | | | | | | | | | | | When eflags has been renamed to the edflags, the kernel doc change were missed. Update kernel doc accordingly. Fixes: b1a92e94560d ("gpiolib: cdev: consolidate edge detector configuration flags") Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Kent Gibson <warthog618@gmail.com>
* | gpiolib: cdev: Add missing header(s)Andy Shevchenko2022-10-241-1/+3
|/ | | | | | | | | | Do not imply that some of the generic headers may be always included. Instead, include explicitly what we are direct user of. While at it, sort headers alphabetically. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Rewiewed-by: Kent Gibson <warthog618@gmail.com>
* Merge tag 'gpio-updates-for-v6.1-rc1' of ↵Linus Torvalds2022-10-081-0/+18
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux Pull gpio updates from Bartosz Golaszewski: "We have a single new driver, support for a bunch of new models, improvements in drivers and core gpiolib code as well device-tree bindings changes. Summary: New driver: - IMX System Controller Unit GPIOs GPIO core: - add fdinfo output for the GPIO character device file descriptors (allows user-space to determine which processes own which GPIO lines) - improvements to OF GPIO code - new quirk for Asus UM325UAZ in gpiolib-acpi - new quirk for Freescale SPI in gpiolib-of Driver improvements: - add a new macro that reduces the amount of boilerplate code in ISA drivers and use it in relevant drivers - support two new models in gpio-pca953x - support new model in gpio-f7188x - convert more drivers to use immutable irq chips - other minor tweaks Device-tree bindings: - add DT bindings for gpio-imx-scu - convert Xilinx GPIO bindings to YAML - reference the properties from the SPI peripheral device-tree bindings instead of providing custom ones in the GPIO controller document - add parsing of GPIO hog nodes to the DT bindings for gpio-mpfs-gpio - relax the node name requirements in gpio-stmpe - add new models for gpio-rcar and gpio-pxa95xx - add a new vendor prefix: Diodes (for Diodes, Inc.) Misc: - pulled in the immutable branch from the x86 platform drivers tree including support for a new simatic board that depends on GPIO changes" * tag 'gpio-updates-for-v6.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux: (36 commits) gpio: tc3589x: Make irqchip immutable gpiolib: cdev: add fdinfo output for line request file descriptors gpio: twl4030: Reorder functions which allows to drop a forward declaraion gpiolib: fix OOB access in quirk callbacks gpiolib: of: factor out conversion from OF flags gpiolib: rework quirk handling in of_find_gpio() gpiolib: of: make Freescale SPI quirk similar to all others gpiolib: of: do not ignore requested index when applying quirks gpio: ws16c48: Ensure number of irq matches number of base gpio: 104-idio-16: Ensure number of irq matches number of base gpio: 104-idi-48: Ensure number of irq matches number of base gpio: 104-dio-48e: Ensure number of irq matches number of base counter: 104-quad-8: Ensure number of irq matches number of base isa: Introduce the module_isa_driver_with_irq helper macro gpio: pca953x: Add support for PCAL6534 gpio: pca953x: Swap if statements to save later complexity gpio: pca953x: Fix pca953x_gpio_set_pull_up_down() dt-bindings: gpio: pca95xx: add entry for pcal6534 and PI4IOE5V6534Q dt-bindings: vendor-prefixes: add Diodes gpio: mt7621: Switch to use platform_get_irq() function ...
| * gpiolib: cdev: add fdinfo output for line request file descriptorsBartosz Golaszewski2022-09-261-0/+18
| | | | | | | | | | | | | | | | | | | | | | Add fdinfo output for file descriptors created for user-space line requests in GPIO uAPI v2. The fdinfo file now contains the name of the GPIO chip that is the "parent" of the request as well as offsets of the lines requested. This allows user-space to parse the /proc/$PID/fdinfo entries and deduce the PID of the process that requested a specific line. Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl> Reviewed-by: Kent Gibson <warthog618@gmail.com>
* | gpiolib: cdev: Set lineevent_state::irq after IRQ register successfullyMeng Li2022-09-211-2/+3
|/ | | | | | | | | | | | | | | | | | | | | | | | | | When running gpio test on nxp-ls1028 platform with below command gpiomon --num-events=3 --rising-edge gpiochip1 25 There will be a warning trace as below: Call trace: free_irq+0x204/0x360 lineevent_free+0x64/0x70 gpio_ioctl+0x598/0x6a0 __arm64_sys_ioctl+0xb4/0x100 invoke_syscall+0x5c/0x130 ...... el0t_64_sync+0x1a0/0x1a4 The reason of this issue is that calling request_threaded_irq() function failed, and then lineevent_free() is invoked to release the resource. Since the lineevent_state::irq was already set, so the subsequent invocation of free_irq() would trigger the above warning call trace. To fix this issue, set the lineevent_state::irq after the IRQ register successfully. Fixes: 468242724143 ("gpiolib: cdev: refactor lineevent cleanup into lineevent_free") Cc: stable@vger.kernel.org Signed-off-by: Meng Li <Meng.Li@windriver.com> Reviewed-by: Kent Gibson <warthog618@gmail.com> Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
* Merge tag 'gpio-updates-for-v6.0-rc1' of ↵Linus Torvalds2022-08-041-140/+151
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux Pull gpio updates from Bartosz Golaszewski: "Here are the updates for this merge window from the GPIO subsystem. We have more lines removed than added thanks to dropping of a driver for a platform that's no longer supported. Otherwise the changes are pretty straightforward: support for some new models, various improvements to existing drivers, some tweaks to the core library code and DT bindings updates. Summary: - remove gpio-vr41xx driver as the only platform using it got dropped too - add support for suspend/resume to gpio-davinci - improvements to the GPIO character device code - add support for disabling bias for in-kernel users (up until now only user-space could set it) - drop unused devm_gpio_free() - fix a refcount issue in gpiolib OF - use device match helpers where applicable - add support for a new model to gpio-rockchip - non-functional improvements in gpio-adp5588 - improve and simplify teardown in gpio-twl4030 and gpio-ucb1400 - modernize the gpio-74xx-mmio and gpio-adnp drivers - coding style improvements in gpio-xilinx, gpio-104-idi-48 - support new model (pca9571) in gpio-pca9570 - convert the DT bindings to YAML for gpio-mvebu and update the document - don't return error codes from remove() in gpio-brcmstb - add a library for the intel 8255 PPI interface and use it in drivers - reduce using magic numbers and improve code readability in several drivers - convert DT bindings to YAML for gpio-tpic2810 - add new models to DT bindings for gpio-frl-imx - Kconfig improvements - other minor tweaks and improvements" * tag 'gpio-updates-for-v6.0-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux: (52 commits) dt-bindings: gpio: fsl-imx-gpio: Add i.MXRT compatibles gpio: 74xx-mmio: Use bits instead of plain numbers for flags gpio: xilinx: add missing blank line after declarations MAINTAINERS: Update Intel 8255 GPIO driver file list gpio: gpio-mm: Implement and utilize register structures gpio: 104-idi-48: Implement and utilize register structures gpio: 104-dio-48e: Implement and utilize register structures gpio: i8255: Introduce the Intel 8255 interface library module gpio: 104-idio-16: Implement and utilize register structures gpio: ws16c48: Implement and utilize register structures gpio: remove VR41XX related gpio driver dt-bindings: gpio: add pull-disable flag gpiolib: acpi: support bias pull disable gpiolib: of: support bias pull disable gpiolib: add support for bias pull disable gpio: 74xx-mmio: use bits.h macros for all masks gpio: 74xx-mmio: Check MMIO_74XX_DIR_IN flag in mmio_74xx_dir_in() gpio: 74xx-mmio: Make use of device properties gpiolib: cdev: compile out HTE unless CONFIG_HTE selected gpiolib: cdev: consolidate edge detector configuration flags ...
| * gpiolib: cdev: compile out HTE unless CONFIG_HTE selectedKent Gibson2022-07-191-35/+63
| | | | | | | | | | | | | | | | | | | | The majority of builds do not include HTE, so compile out hte functionality unless CONFIG_HTE is selected. Signed-off-by: Kent Gibson <warthog618@gmail.com> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
| * gpiolib: cdev: consolidate edge detector configuration flagsKent Gibson2022-07-191-66/+60
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Combine the polarity_change flag, struct line eflags, and hte enable flag into a single flag variable. The combination of these flags describes the configuration state of the edge detector, so formalize and clarify that by combining them into a single variable, edflags, in struct line. The edflags is a subset of the GPIO_V2_LINE_FLAGsb relevant to the edge detector, and is also a superset of the eflags it replaces. The eflags name is still used to describe the subset of edflags corresponding to the rising/falling edge flags where edflags is masked down to that subset. This consolidation reduces the number of variables being passed, simplifies state comparisons, and provides a more extensible foundation should additional edge sources be integrated in the future. Signed-off-by: Kent Gibson <warthog618@gmail.com> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
| * gpiolib: cdev: simplify line event identificationKent Gibson2022-07-191-29/+15
| | | | | | | | | | | | | | | | | | | | Reorganise line event identification code to reduce code duplication, and replace if-else initializers with a helper function to improve readability. Signed-off-by: Kent Gibson <warthog618@gmail.com> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
| * gpiolib: cdev: replace if-else chains with switchesKent Gibson2022-07-191-13/+18
| | | | | | | | | | | | | | | | | | | | Improve readability by replacing if-else chains with switch statements. Signed-off-by: Kent Gibson <warthog618@gmail.com> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
| * gpiolib: cdev: simplify parameter in call to hte_edge_setupKent Gibson2022-07-191-3/+1
| | | | | | | | | | | | | | | | | | | | | | | | Improve readability by using the GPIO_V2_LINE_FLAG_EDGE_BOTH instead of combining the rising and falling edge flags. Signed-off-by: Kent Gibson <warthog618@gmail.com> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Acked-by: Dipen Patel <dipenp@nvidia.com> Tested-by: Dipen Patel <dipenp@nvidia.com> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
| * gpiolib: cdev: simplify linereq_freeKent Gibson2022-07-191-4/+4
| | | | | | | | | | | | | | | | | | | | | | | | The edge detector is only ever started after the line desc has been determined, so move edge_detector_stop() inside the line desc check, and merge the two checked regions into one. Signed-off-by: Kent Gibson <warthog618@gmail.com> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Acked-by: Dipen Patel <dipenp@nvidia.com> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
* | Merge tag 'hte/for-5.19' of ↵Linus Torvalds2022-07-181-0/+4
|\ \ | |/ |/| | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tegra/linux Pull hardware timestamp fix from Thierry Reding: "A single fix for an out-of-sync kerneldoc comment" * tag 'hte/for-5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/tegra/linux: gpiolib: cdev: Fix kernel doc for struct line
| * gpiolib: cdev: Fix kernel doc for struct lineAndy Shevchenko2022-06-171-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Kernel doc validator is not happy: gpiolib-cdev.c:487: warning: Function parameter or member 'hdesc' not described in 'line' gpiolib-cdev.c:487: warning: Function parameter or member 'raw_level' not described in 'line' gpiolib-cdev.c:487: warning: Function parameter or member 'total_discard_seq' not described in 'line' gpiolib-cdev.c:487: warning: Function parameter or member 'last_seqno' not described in 'line' Describe above mentioned parameters. Fixes: 2068339a6c35 ("gpiolib: cdev: Add hardware timestamp clock type") Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Dipen Patel <dipenp@nvidia.com> Acked-by: Bartosz Golaszewski <brgl@bgdev.pl> Signed-off-by: Thierry Reding <treding@nvidia.com>