kernel/include/linux/gpio/driver.h, branch linux-5.16.y

gpio: Restrict usage of GPIO chip irq members before initialization

2022-04-13T18:03:21Z

commit 5467801f1fcbdc46bc7298a84dbf3ca1ff2a7320 upstream. GPIO chip irq members are exposed before they could be completely initialized and this leads to race conditions. One such issue was observed for the gc->irq.domain variable which was accessed through the I2C interface in gpiochip_to_irq() before it could be initialized by gpiochip_add_irqchip(). This resulted in Kernel NULL pointer dereference. Following are the logs for reference :- kernel: Call Trace: kernel: gpiod_to_irq+0x53/0x70 kernel: acpi_dev_gpio_irq_get_by+0x113/0x1f0 kernel: i2c_acpi_get_irq+0xc0/0xd0 kernel: i2c_device_probe+0x28a/0x2a0 kernel: really_probe+0xf2/0x460 kernel: RIP: 0010:gpiochip_to_irq+0x47/0xc0 To avoid such scenarios, restrict usage of GPIO chip irq members before they are completely initialized. Signed-off-by: Shreeya Patel Cc: stable@vger.kernel.org Reviewed-by: Andy Shevchenko Reviewed-by: Linus Walleij Signed-off-by: Bartosz Golaszewski Signed-off-by: Greg Kroah-Hartman

gpio: Allow per-parent interrupt data

2021-10-26T22:16:00Z

The core gpiolib code is able to deal with multiple interrupt parents for a single gpio irqchip. It however only allows a single piece of data to be conveyed to all flow handlers (either the gpio_chip or some other, driver-specific data). This means that drivers have to go through some interesting dance to find the correct context, something that isn't great in interrupt context (see aebdc8abc9db86e2bd33070fc2f961012fff74b4 for a prime example). Instead, offer an optional way for a pinctrl/gpio driver to provide an array of pointers which gets used to provide the correct context to the flow handler. Signed-off-by: Marc Zyngier Signed-off-by: Joey Gouly Reviewed-by: Linus Walleij Link: https://lore.kernel.org/r/20211026175815.52703-2-joey.gouly@arm.com Signed-off-by: Linus Walleij

gpiolib: convert 'devprop_gpiochip_set_names' to support multiple gpiochip banks per device

2021-07-29T17:41:12Z

The default gpiolib-of implementation does not work with the multiple gpiochip banks per device structure used for example by the gpio-mt7621 and gpio-brcmstb drivers. To fix these kind of situations driver code is forced to fill the names to avoid the gpiolib code to set names repeated along the banks. Instead of continue with that antipattern fix the gpiolib core function to get expected behaviour for every single situation adding a field 'offset' in the gpiochip structure. Doing in this way, we can assume this offset will be zero for normal driver code where only one gpiochip bank per device is used but can be set explicitly in those drivers that really need more than one gpiochip. Reviewed-by: Andy Shevchenko Reviewed-by: Gregory Fong Signed-off-by: Sergio Paracuellos Signed-off-by: Bartosz Golaszewski

Merge tag 'gpio-updates-for-v5.13-v2' of git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux

2021-05-05T19:39:29Z

Pull gpio updates from Bartosz Golaszewski: - new driver for the Realtek Otto GPIO controller - ACPI support for gpio-mpc8xxx - edge event support for gpio-sch (+ Kconfig fixes) - Kconfig improvements in gpio-ich - fixes to older issues in gpio-mockup - ACPI quirk for ignoring EC wakeups on Dell Venue 10 Pro 5055 - improve the GPIO aggregator code by using more generic interfaces instead of reimplementing them in the driver - convert the DT bindings for gpio-74x164 to yaml - documentation improvements - a slew of other minor fixes and improvements to GPIO drivers * tag 'gpio-updates-for-v5.13-v2' of git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux: (34 commits) dt-bindings: gpio: add YAML description for rockchip,gpio-bank gpio: mxs: remove useless function dt-bindings: gpio: fairchild,74hc595: Convert to json-schema gpio: it87: remove unused code gpio: 104-dio-48e: Fix coding style issues gpio: mpc8xxx: Add ACPI support gpio: ich: Switch to be dependent on LPC_ICH gpio: sch: Drop MFD_CORE selection gpio: sch: depends on LPC_SCH gpiolib: acpi: Add quirk to ignore EC wakeups on Dell Venue 10 Pro 5055 gpio: sch: Hook into ACPI GPE handler to catch GPIO edge events gpio: sch: Add edge event support gpio: aggregator: Replace custom get_arg() with a generic next_arg() lib/cmdline: Export next_arg() for being used in modules gpio: omap: Use device_get_match_data() helper gpio: Add Realtek Otto GPIO support dt-bindings: gpio: Binding for Realtek Otto GPIO docs: kernel-parameters: Add gpio_mockup_named_lines docs: kernel-parameters: Move gpio-mockup for alphabetic order lib: bitmap: provide devm_bitmap_alloc() and devm_bitmap_zalloc() ...

gpio: guard gpiochip_irqchip_add_domain() with GPIOLIB_IRQCHIP

2021-03-29T10:20:07Z

The current code doesn't check if GPIOLIB_IRQCHIP is enabled, which results in a compilation error when trying to build gpio-regmap if CONFIG_GPIOLIB_IRQCHIP isn't enabled. Fixes: 6a45b0e2589f ("gpiolib: Introduce gpiochip_irqchip_add_domain()") Suggested-by: Michael Walle Signed-off-by: Álvaro Fernández Rojas Reviewed-by: Linus Walleij Reviewed-by: Michael Walle Acked-by: Bartosz Golaszewski Link: https://lore.kernel.org/r/20210324081923.20379-2-noltari@gmail.com Signed-off-by: Linus Walleij

gpiolib: some edits of kernel docs for clarity

2021-03-26T13:56:19Z

Fix a few typos and some punctuation. Also, change CONFIG_OF to CONFIG_OF_GPIO in one comment. Signed-off-by: Randy Dunlap Cc: Linus Walleij Cc: Bartosz Golaszewski Cc: linux-gpio@vger.kernel.org Reviewed-by: Linus Walleij [Bartosz: tweaked the commit message] Signed-off-by: Bartosz Golaszewski

gpio: Retire the explicit gpio irqchip code

2020-10-28T14:50:06Z

Now that all gpiolib irqchip users have been over to use the irqchip template, we can finally retire the old code path and leave just one way in to the irqchip: set up the template when registering the gpio_chip. For a while we had two code paths for this which was a bit confusing. This brings this work to a conclusion, there is now one way of doing this. Signed-off-by: Linus Walleij Reviewed-by: Andy Shevchenko Cc: Thierry Reding Link: https://lore.kernel.org/r/20201019134046.65101-1-linus.walleij@linaro.org

gpiolib: unexport devprop_gpiochip_set_names()

2020-09-14T08:54:42Z

Now that devprop_gpiochip_set_names() is only used in a single place inside drivers/gpio/gpiolib.c, there's no need anymore for it to be exported or to even live in its own source file. Pull this function into the core source file for gpiolib. Signed-off-by: Bartosz Golaszewski Reviewed-by: Mika Westerberg Reviewed-by: Andy Shevchenko

gpiolib: generalize devprop_gpiochip_set_names() for device properties

2020-09-14T08:54:01Z

devprop_gpiochip_set_names() is overly complicated with taking the fwnode argument (which requires using dev_fwnode() & of_fwnode_handle() in ACPI and OF GPIO code respectively). Let's just switch to using the generic device properties. This allows us to pull the code setting line names directly into gpiochip_add_data_with_key() instead of handling it separately for ACPI and OF. Signed-off-by: Bartosz Golaszewski Reviewed-by: Andy Shevchenko Reviewed-by: Mika Westerberg

gpio: don't use same lockdep class for all devm_gpiochip_add_data users

2020-08-03T23:22:02Z

Commit 959bc7b22bd2 ("gpio: Automatically add lockdep keys") documents in its commits message its intention to "create a unique class key for each driver". It does so by having gpiochip_add_data add in-place the definition of two static lockdep classes for LOCKDEP use. That way, every caller of the macro adds their gpiochip with unique lockdep classes. There are many indirect callers of gpiochip_add_data, however, via use of devm_gpiochip_add_data. devm_gpiochip_add_data has external linkage and all its users will share the same lockdep classes, which probably is not intended. Fix this by replicating the gpio_chip_add_data statics-in-macro for the devm_ version as well. Fixes: 959bc7b22bd2 ("gpio: Automatically add lockdep keys") Signed-off-by: Ahmad Fatoum Reviewed-by: Andy Shevchenko Reviewed-by: Bartosz Golaszewski Link: https://lore.kernel.org/r/20200731123835.8003-1-a.fatoum@pengutronix.de Signed-off-by: Linus Walleij