[PATCH 4/5] gpiolib / ACPI: allow passing GPIOF_ACTIVE_LOW for GpioInt resources

From: Mika Westerberg
Date: Tue Oct 01 2013 - 10:59:41 EST


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@xxxxxxxxxxxxxxx>
---
drivers/gpio/gpiolib-acpi.c | 2 ++
drivers/gpio/gpiolib.c | 12 +++++++++++-
include/linux/acpi_gpio.h | 2 ++
3 files changed, 15 insertions(+), 1 deletion(-)

diff --git a/drivers/gpio/gpiolib-acpi.c b/drivers/gpio/gpiolib-acpi.c
index 333297c..4c6df41 100644
--- a/drivers/gpio/gpiolib-acpi.c
+++ b/drivers/gpio/gpiolib-acpi.c
@@ -251,6 +251,8 @@ 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 1e099de..b01a231 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -2115,7 +2115,17 @@ static struct gpio_desc *of_find_gpio(struct device *dev, const char *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,
diff --git a/include/linux/acpi_gpio.h b/include/linux/acpi_gpio.h
index bbfa83a..af599ec 100644
--- a/include/linux/acpi_gpio.h
+++ b/include/linux/acpi_gpio.h
@@ -10,9 +10,11 @@
/**
* struct acpi_gpio_info - ACPI GPIO specific information
* @gpioint: if %true this GPIO is of type GpioInt otherwise type is GpioIo
+ * @active_low: in case of @gpioint, the pin is active low
*/
struct acpi_gpio_info {
bool gpioint;
+ bool active_low;
};

#ifdef CONFIG_GPIO_ACPI
--
1.8.4.rc3

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