gpiolib-acpi: introduce acpi_get_gpio_by_index() helper

Instead of open-coding ACPI GPIO resource lookup in each driver, we provide
a helper function analogous to Device Tree version that allows drivers to
specify which GPIO resource they are interested (using an index to the GPIO
resources). The function then finds out the correct resource, translates
the ACPI GPIO number to the corresponding Linux GPIO number and returns
that.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

1 files changed, 17 insertions, 0 deletions

diff --git a/include/linux/acpi_gpio.h b/include/linux/acpi_gpio.h
index 213135f44333..4c120a1e0ca3 100644
--- a/include/linux/acpi_gpio.h
+++ b/include/linux/acpi_gpio.h
@@ -1,12 +1,23 @@
 #ifndef _LINUX_ACPI_GPIO_H_
 #define _LINUX_ACPI_GPIO_H_
 
+#include <linux/device.h>
 #include <linux/errno.h>
 #include <linux/gpio.h>
 
+/**
+ * struct acpi_gpio_info - ACPI GPIO specific information
+ * @gpioint: if %true this GPIO is of type GpioInt otherwise type is GpioIo
+ */
+struct acpi_gpio_info {
+	bool gpioint;
+};
+
 #ifdef CONFIG_GPIO_ACPI
 
 int acpi_get_gpio(char *path, int pin);
+int acpi_get_gpio_by_index(struct device *dev, int index,
+			   struct acpi_gpio_info *info);
 void acpi_gpiochip_request_interrupts(struct gpio_chip *chip);
 void acpi_gpiochip_free_interrupts(struct gpio_chip *chip);
 
@@ -17,6 +28,12 @@ static inline int acpi_get_gpio(char *path, int pin)
 	return -ENODEV;
 }
 
+static inline int acpi_get_gpio_by_index(struct device *dev, int index,
+					 struct acpi_gpio_info *info)
+{
+	return -ENODEV;
+}
+
 static inline void acpi_gpiochip_request_interrupts(struct gpio_chip *chip) { }
 static inline void acpi_gpiochip_free_interrupts(struct gpio_chip *chip) { }