gpiolib / ACPI: allow passing GPIOF_ACTIVE_LOW for GpioInt resources

The ACPI GpioInt resources contain polarity field that is used to specify
whether the interrupt is active high or low. Since gpiolib supports
GPIOF_ACTIVE_LOW we can pass this information in the flags field in
acpi_find_gpio(), analogous to the DeviceTree version.

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

2 files changed, 13 insertions, 1 deletions

diff --git a/drivers/gpio/gpiolib-acpi.c b/drivers/gpio/gpiolib-acpi.c
index 03187d0a3045..ae0ffdce8bd5 100644
--- a/drivers/gpio/gpiolib-acpi.c
+++ b/drivers/gpio/gpiolib-acpi.c
@@ -253,6 +253,8 @@ static int acpi_find_gpio(struct acpi_resource *ares, void *data)
                                               agpio->pin_table[0]);
                 lookup->info.gpioint =
                         agpio->connection_type == ACPI_RESOURCE_GPIO_TYPE_INT;
+                lookup->info.active_low =
+                        agpio->polarity == ACPI_ACTIVE_LOW;
         }
 
         return 1;
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index bee93c8c2361..9f3326b95e60 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -2264,7 +2264,17 @@ static struct gpio_desc *of_find_gpio(struct device *dev, const char *con_id,
 static struct gpio_desc *acpi_find_gpio(struct device *dev, const char *con_id,
                                         unsigned int idx, unsigned long *flags)
 {
-        return acpi_get_gpiod_by_index(dev, idx, NULL);
+        struct acpi_gpio_info info;
+        struct gpio_desc *desc;
+
+        desc = acpi_get_gpiod_by_index(dev, idx, &info);
+        if (IS_ERR(desc))
+                return desc;
+
+        if (info.gpioint && info.active_low)
+                *flags |= GPIOF_ACTIVE_LOW;
+
+        return desc;
 }
 
 static struct gpio_desc *gpiod_find(struct device *dev, const char *con_id,