[PATCH v1] gpio: acpi: Add managed variant of acpi_dev_add_driver_gpios()

[Andy Shevchenko]

Introduce device managed variant of acpi_dev_add_driver_gpios() and its
counterpart acpi_dev_remove_driver_gpios().

The functions in most cases are used in driver's ->probe() and
->remove() callbacks, that's why it's useful to have managed variant of
them.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
---

This is supposed to go through GPIO tree.

Linus, can you create an immutable branch that other subsystems can use
it if needed?

(We currently have one possible leak and devm_*() would help there)

 drivers/gpio/gpiolib-acpi.c | 31 +++++++++++++++++++++++++++++++
 include/linux/acpi.h        | 11 +++++++++++
 2 files changed, 42 insertions(+)

diff --git a/drivers/gpio/gpiolib-acpi.c b/drivers/gpio/gpiolib-acpi.c
index 1459e6183194..3fe63d8ed426 100644
--- a/drivers/gpio/gpiolib-acpi.c
+++ b/drivers/gpio/gpiolib-acpi.c
@@ -362,6 +362,37 @@ int acpi_dev_add_driver_gpios(struct acpi_device *adev,
 }
 EXPORT_SYMBOL_GPL(acpi_dev_add_driver_gpios);
 
+static void devm_acpi_dev_release_driver_gpios(struct device *dev, void *res)
+{
+	acpi_dev_remove_driver_gpios(ACPI_COMPANION(dev));
+}
+
+int devm_acpi_dev_add_driver_gpios(struct device *dev,
+				   const struct acpi_gpio_mapping *gpios)
+{
+	void *res;
+	int ret;
+
+	res = devres_alloc(devm_acpi_dev_release_driver_gpios, 0, GFP_KERNEL);
+	if (!res)
+		return -ENOMEM;
+
+	ret = acpi_dev_add_driver_gpios(ACPI_COMPANION(dev), gpios);
+	if (ret) {
+		devres_free(res);
+		return ret;
+	}
+	devres_add(dev, res);
+	return 0;
+}
+EXPORT_SYMBOL_GPL(devm_acpi_dev_add_driver_gpios);
+
+void devm_acpi_dev_remove_driver_gpios(struct device *dev)
+{
+	WARN_ON(devres_release(dev, devm_acpi_dev_release_driver_gpios, NULL, NULL));
+}
+EXPORT_SYMBOL_GPL(devm_acpi_dev_remove_driver_gpios);
+
 static bool acpi_get_driver_gpio_data(struct acpi_device *adev,
 				      const char *name, int index,
 				      struct acpi_reference_args *args)
diff --git a/include/linux/acpi.h b/include/linux/acpi.h
index 673acda012af..c8eaaad4a9ed 100644
--- a/include/linux/acpi.h
+++ b/include/linux/acpi.h
@@ -952,6 +952,10 @@ static inline void acpi_dev_remove_driver_gpios(struct acpi_device *adev)
 		adev->driver_gpios = NULL;
 }
 
+int devm_acpi_dev_add_driver_gpios(struct device *dev,
+				   const struct acpi_gpio_mapping *gpios);
+void devm_acpi_dev_remove_driver_gpios(struct device *dev);
+
 int acpi_dev_gpio_irq_get(struct acpi_device *adev, int index);
 #else
 static inline int acpi_dev_add_driver_gpios(struct acpi_device *adev,
@@ -961,6 +965,13 @@ static inline int acpi_dev_add_driver_gpios(struct acpi_device *adev,
 }
 static inline void acpi_dev_remove_driver_gpios(struct acpi_device *adev) {}
 
+static inline int devm_acpi_dev_add_driver_gpios(struct device *dev,
+			      const struct acpi_gpio_mapping *gpios)
+{
+	return -ENXIO;
+}
+static inline void devm_acpi_dev_remove_driver_gpios(struct device *dev) {}
+
 static inline int acpi_dev_gpio_irq_get(struct acpi_device *adev, int index)
 {
 	return -ENXIO;
-- 
2.11.0