[PATCH] gpiolib: acpi: Support GpioInt with active_low polarity

[Ricardo Ribalda <ribalda@chromium.org>]

On the current implementation we only support active_high polarity for
GpioInt.

There can be cases where a GPIO has active_low polarity and it is also a
IRQ source.

De-couple the irq_polarity and active_low fields instead of re-use it.

With this patch we support ACPI devices such as:

Name (_CRS, ResourceTemplate ()  // _CRS: Current Resource Settings
{
        GpioInt (Edge, ActiveBoth, Exclusive, PullDefault, 0x0000,
        "\\_SB.PCI0.GPIO", 0x00, ResourceConsumer, ,
        )
        {   // Pin list
                0x0064
        }
})
Name (_DSD, Package (0x02)  // _DSD: Device-Specific Data
{
        ToUUID ("daffd814-6eba-4d8c-8a91-bc9bbf4aa301") /* Device Properties for _DSD */,
        Package (0x01)
        {
        Package (0x02)
        {
                "privacy-gpio",
                Package (0x04)
                {
                \_SB.PCI0.XHCI.RHUB.HS07,
                Zero,
                Zero,
                One
                }
        }
        }
})

Signed-off-by: Ricardo Ribalda <ribalda@chromium.org>
---
 drivers/gpio/gpiolib-acpi.c | 8 ++++----
 drivers/gpio/gpiolib-acpi.h | 6 ++++--
 2 files changed, 8 insertions(+), 6 deletions(-)

diff --git a/drivers/gpio/gpiolib-acpi.c b/drivers/gpio/gpiolib-acpi.c
index 834a12f3219e..bc33c1056391 100644
--- a/drivers/gpio/gpiolib-acpi.c
+++ b/drivers/gpio/gpiolib-acpi.c
@@ -624,7 +624,7 @@ int acpi_gpio_update_gpiod_lookup_flags(unsigned long *lookupflags,
 		break;
 	}
 
-	if (info->polarity == GPIO_ACTIVE_LOW)
+	if (info->active_low)
 		*lookupflags |= GPIO_ACTIVE_LOW;
 
 	return 0;
@@ -665,6 +665,7 @@ static int acpi_populate_gpio_lookup(struct acpi_resource *ares, void *data)
 					      agpio->pin_table[pin_index]);
 		lookup->info.pin_config = agpio->pin_config;
 		lookup->info.gpioint = gpioint;
+		lookup->info.active_low = !!lookup->active_low;
 
 		/*
 		 * Polarity and triggering are only specified for GpioInt
@@ -675,11 +676,10 @@ static int acpi_populate_gpio_lookup(struct acpi_resource *ares, void *data)
 		 */
 		if (lookup->info.gpioint) {
 			lookup->info.flags = GPIOD_IN;
-			lookup->info.polarity = agpio->polarity;
+			lookup->info.irq_polarity = agpio->polarity;
 			lookup->info.triggering = agpio->triggering;
 		} else {
 			lookup->info.flags = acpi_gpio_to_gpiod_flags(agpio);
-			lookup->info.polarity = lookup->active_low;
 		}
 	}
 
@@ -958,7 +958,7 @@ int acpi_dev_gpio_irq_get(struct acpi_device *adev, int index)
 				return ret;
 
 			irq_flags = acpi_dev_get_irq_type(info.triggering,
-							  info.polarity);
+							  info.irq_polarity);
 
 			/* Set type if specified and different than the current one */
 			if (irq_flags != IRQ_TYPE_NONE &&
diff --git a/drivers/gpio/gpiolib-acpi.h b/drivers/gpio/gpiolib-acpi.h
index 1c6d65cf0629..816a2d7a21ed 100644
--- a/drivers/gpio/gpiolib-acpi.h
+++ b/drivers/gpio/gpiolib-acpi.h
@@ -16,7 +16,8 @@ struct acpi_device;
  * @flags: GPIO initialization flags
  * @gpioint: if %true this GPIO is of type GpioInt otherwise type is GpioIo
  * @pin_config: pin bias as provided by ACPI
- * @polarity: interrupt polarity as provided by ACPI
+ * @irq_polarity: interrupt polarity as provided by ACPI
+ * @active_low: pin polarity as provided by ACPI
  * @triggering: triggering type as provided by ACPI
  * @quirks: Linux specific quirks as provided by struct acpi_gpio_mapping
  */
@@ -25,7 +26,8 @@ struct acpi_gpio_info {
 	enum gpiod_flags flags;
 	bool gpioint;
 	int pin_config;
-	int polarity;
+	int irq_polarity;
+	bool active_low;
 	int triggering;
 	unsigned int quirks;
 };
-- 
2.29.0.rc2.309.g374f81d7ae-goog