6 files changed, 62 insertions, 18 deletions
diff --git a/drivers/gpio/TODO b/drivers/gpio/TODO
index b5f0a7a2e1bf..4b70cbaa1caa 100644
--- a/drivers/gpio/TODO
+++ b/drivers/gpio/TODO
@@ -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.
diff --git a/drivers/gpio/gpio-mpc8xxx.c b/drivers/gpio/gpio-mpc8xxx.c
index 0cd4c36ae8aa..541517536489 100644
--- a/drivers/gpio/gpio-mpc8xxx.c
+++ b/drivers/gpio/gpio-mpc8xxx.c
@@ -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:
diff --git a/drivers/gpio/gpio-tegra186.c b/drivers/gpio/gpio-tegra186.c
index 6895b65c86af..d27bfac6c9f5 100644
--- a/drivers/gpio/gpio-tegra186.c
+++ b/drivers/gpio/gpio-tegra186.c
@@ -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);
-		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);
-		if (IS_ERR(gpio->base))
-			return PTR_ERR(gpio->base);
-	}
+	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);
+
+	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)
diff --git a/drivers/gpio/gpio-zynq.c b/drivers/gpio/gpio-zynq.c
index be81fa2b17ab..3dae63f3ea21 100644
--- a/drivers/gpio/gpio-zynq.c
+++ b/drivers/gpio/gpio-zynq.c
@@ -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);
diff --git a/drivers/gpio/gpiolib-devres.c b/drivers/gpio/gpiolib-devres.c
index 08205f355ceb..120d1ec5af3b 100644
--- a/drivers/gpio/gpiolib-devres.c
+++ b/drivers/gpio/gpiolib-devres.c
@@ -317,11 +317,15 @@ EXPORT_SYMBOL_GPL(devm_gpiod_put);
  * @dev:	GPIO consumer
  * @desc:	GPIO descriptor to remove resource management from
  *
+ * *DEPRECATED*
+ * This function should not be used. It's been provided as a workaround for
+ * resource ownership issues in the regulator framework and should be replaced
+ * with a better solution.
+ *
  * Remove resource management from a GPIO descriptor. This is needed when
  * you want to hand over lifecycle management of a descriptor to another
  * mechanism.
  */
-
 void devm_gpiod_unhinge(struct device *dev, struct gpio_desc *desc)
 {
 	int ret;
diff --git a/drivers/gpio/gpiolib-of.c b/drivers/gpio/gpiolib-of.c
index eb667f8f1ead..65f6a7177b78 100644
--- a/drivers/gpio/gpiolib-of.c
+++ b/drivers/gpio/gpiolib-of.c
@@ -193,6 +193,8 @@ static void of_gpio_try_fixup_polarity(const struct device_node *np,
 		 */
 		{ "himax,hx8357",	"gpios-reset",	false },
 		{ "himax,hx8369",	"gpios-reset",	false },
+#endif
+#if IS_ENABLED(CONFIG_MTD_NAND_JZ4780)
 		/*
 		 * The rb-gpios semantics was undocumented and qi,lb60 (along with
 		 * the ingenic driver) got it wrong. The active state encodes the
@@ -266,6 +268,9 @@ static void of_gpio_set_polarity_by_property(const struct device_node *np,
 		{ "fsl,imx8qm-fec",  "phy-reset-gpios", "phy-reset-active-high" },
 		{ "fsl,s32v234-fec", "phy-reset-gpios", "phy-reset-active-high" },
 #endif
+#if IS_ENABLED(CONFIG_MMC_ATMELMCI)
+		{ "atmel,hsmci",       "cd-gpios",     "cd-inverted" },
+#endif
 #if IS_ENABLED(CONFIG_PCI_IMX6)
 		{ "fsl,imx6q-pcie",  "reset-gpio", "reset-gpio-active-high" },
 		{ "fsl,imx6sx-pcie", "reset-gpio", "reset-gpio-active-high" },
@@ -292,9 +297,6 @@ static void of_gpio_set_polarity_by_property(const struct device_node *np,
 		{ "regulator-gpio",    "enable-gpio",  "enable-active-high" },
 		{ "regulator-gpio",    "enable-gpios", "enable-active-high" },
 #endif
-#if IS_ENABLED(CONFIG_MMC_ATMELMCI)
-		{ "atmel,hsmci",       "cd-gpios",     "cd-inverted" },
-#endif
 	};
 	unsigned int i;
 	bool active_high;