Commit 8f43640c authored Apr 10, 2025 by Linus Torvalds

Merge tag 'gpio-fixes-for-v6.15-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux

Pull gpio fixes from Bartosz Golaszewski:

 - fix resource handling in gpio-tegra186

 - fix wakeup source leaks in gpio-mpc8xxx and gpio-zynq

 - fix minor issues with some GPIO OF quirks

 - deprecate GPIOD_FLAGS_BIT_NONEXCLUSIVE and devm_gpiod_unhinge()
   symbols and add a TODO task to track replacing them with a better
   solution

* tag 'gpio-fixes-for-v6.15-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux:
  gpiolib: of: Move Atmel HSMCI quirk up out of the regulator comment
  gpiolib: of: Fix the choice for Ingenic NAND quirk
  gpio: zynq: Fix wakeup source leaks on device unbind
  gpio: mpc8xxx: Fix wakeup source leaks on device unbind
  gpio: TODO: track the removal of regulator-related workarounds
  MAINTAINERS: add more keywords for the GPIO subsystem entry
  gpio: deprecate devm_gpiod_unhinge()
  gpio: deprecate the GPIOD_FLAGS_BIT_NONEXCLUSIVE flag
  gpio: tegra186: fix resource handling in ACPI probe path

parents b4991c01 b8c7a1ac

MAINTAINERS

+2 −0

Original line number	Diff line number	Diff line
		@@ -10151,6 +10151,8 @@ F: include/linux/gpio.h
		F: include/linux/gpio/
		F: include/linux/of_gpio.h
		K: (devm_)?gpio_(request\|free\|direction\|get\|set)
		K: GPIOD_FLAGS_BIT_NONEXCLUSIVE
		K: devm_gpiod_unhinge

		GPIO UAPI
		M: Bartosz Golaszewski <brgl@bgdev.pl>

drivers/gpio/TODO

+34 −0

Original line number	Diff line number	Diff line
		@@ -186,3 +186,37 @@ their hardware offsets within the chip.

		Encourage users to switch to using them and eventually remove the existing
		global export/unexport attribues.

		-------------------------------------------------------------------------------

		Remove GPIOD_FLAGS_BIT_NONEXCLUSIVE

		GPIOs in the linux kernel are meant to be an exclusive resource. This means
		that the GPIO descriptors (the software representation of the hardware concept)
		are not reference counted and - in general - only one user at a time can
		request a GPIO line and control its settings. The consumer API is designed
		around full control of the line's state as evidenced by the fact that, for
		instance, gpiod_set_value() does indeed drive the line as requested, instead
		of bumping an enable counter of some sort.

		A problematic use-case for GPIOs is when two consumers want to use the same
		descriptor independently. An example of such a user is the regulator subsystem
		which may instantiate several struct regulator_dev instances containing
		a struct device but using the same enable GPIO line.

		A workaround was introduced in the form of the GPIOD_FLAGS_BIT_NONEXCLUSIVE
		flag but its implementation is problematic: it does not provide any
		synchronization of usage nor did it introduce any enable count meaning the
		non-exclusive users of the same descriptor will in fact "fight" for the
		control over it. This flag should be removed and replaced with a better
		solution, possibly based on the new power sequencing subsystem.

		-------------------------------------------------------------------------------

		Remove devm_gpiod_unhinge()

		devm_gpiod_unhinge() is provided as a way to transfer the ownership of managed
		enable GPIOs to the regulator core. Rather than doing that however, we should
		make it possible for the regulator subsystem to deal with GPIO resources the
		lifetime of which it doesn't control as logically, a GPIO obtained by a caller
		should also be freed by it.

drivers/gpio/gpio-mpc8xxx.c

+3 −1

Original line number	Diff line number	Diff line
		@@ -410,7 +410,9 @@ static int mpc8xxx_probe(struct platform_device *pdev)
		goto err;
		}

		device_init_wakeup(dev, true);
		ret = devm_device_init_wakeup(dev);
		if (ret)
		return dev_err_probe(dev, ret, "Failed to init wakeup\n");

		return 0;
		err:

drivers/gpio/gpio-tegra186.c

+14 −13

Original line number	Diff line number	Diff line
		@@ -823,6 +823,7 @@ static int tegra186_gpio_probe(struct platform_device *pdev)
		struct gpio_irq_chip *irq;
		struct tegra_gpio *gpio;
		struct device_node *np;
		struct resource *res;
		char **names;
		int err;

		@@ -842,19 +843,19 @@ static int tegra186_gpio_probe(struct platform_device *pdev)
		gpio->num_banks++;

		/* get register apertures */
		gpio->secure = devm_platform_ioremap_resource_byname(pdev, "security");
		if (IS_ERR(gpio->secure)) {
		gpio->secure = devm_platform_ioremap_resource(pdev, 0);
		res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "security");
		if (!res)
		res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
		gpio->secure = devm_ioremap_resource(&pdev->dev, res);
		if (IS_ERR(gpio->secure))
		return PTR_ERR(gpio->secure);
		}

		gpio->base = devm_platform_ioremap_resource_byname(pdev, "gpio");
		if (IS_ERR(gpio->base)) {
		gpio->base = devm_platform_ioremap_resource(pdev, 1);
		res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "gpio");
		if (!res)
		res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
		gpio->base = devm_ioremap_resource(&pdev->dev, res);
		if (IS_ERR(gpio->base))
		return PTR_ERR(gpio->base);
		}

		err = platform_irq_count(pdev);
		if (err < 0)

drivers/gpio/gpio-zynq.c

+1 −0

Original line number	Diff line number	Diff line
		@@ -1011,6 +1011,7 @@ static void zynq_gpio_remove(struct platform_device *pdev)
		ret = pm_runtime_get_sync(&pdev->dev);
		if (ret < 0)
		dev_warn(&pdev->dev, "pm_runtime_get_sync() Failed\n");
		device_init_wakeup(&pdev->dev, 0);
		gpiochip_remove(&gpio->chip);
		device_set_wakeup_capable(&pdev->dev, 0);
		pm_runtime_disable(&pdev->dev);