[PATCH 4/5] acpi: gsi: Use acpi_gsi_descriptor to allocate interrupts

[Marc Zyngier]

Now that the irqdomain layer is a bit more ACPI friendly, add the
mapping code that allows irq_create_acpi_mapping to be called.

As we only support the GIC so far, support is pretty limited.

Signed-off-by: Marc Zyngier <marc.zyngier at arm.com>
---
 drivers/acpi/gsi.c | 54 ++++++++++++++++++++++++++++++++++++------------------
 1 file changed, 36 insertions(+), 18 deletions(-)

diff --git a/drivers/acpi/gsi.c b/drivers/acpi/gsi.c
index 38208f2..005d843 100644
--- a/drivers/acpi/gsi.c
+++ b/drivers/acpi/gsi.c
@@ -33,6 +33,12 @@ static unsigned int acpi_gsi_get_irq_type(int trigger, int polarity)
 	}
 }
 
+static struct irq_domain *irq_find_acpi_domain(enum acpi_irq_model_id id,
+					       enum irq_domain_bus_token bus_token)
+{
+	return irq_find_matching_host((void *)id, bus_token);
+}
+
 /**
  * acpi_gsi_to_irq() - Retrieve the linux irq number for a given GSI
  * @gsi: GSI IRQ number to map
@@ -45,12 +51,10 @@ static unsigned int acpi_gsi_get_irq_type(int trigger, int polarity)
  */
 int acpi_gsi_to_irq(u32 gsi, unsigned int *irq)
 {
-	/*
-	 * Only default domain is supported at present, always find
-	 * the mapping corresponding to default domain by passing NULL
-	 * as irq_domain parameter
-	 */
-	*irq = irq_find_mapping(NULL, gsi);
+	struct irq_domain *d = irq_find_acpi_domain(acpi_irq_model,
+						    DOMAIN_BUS_ANY);
+
+	*irq = irq_find_mapping(d, gsi);
 	/*
 	 * *irq == 0 means no mapping, that should
 	 * be reported as a failure
@@ -72,23 +76,35 @@ EXPORT_SYMBOL_GPL(acpi_gsi_to_irq);
 int acpi_register_gsi(struct device *dev, u32 gsi, int trigger,
 		      int polarity)
 {
-	unsigned int irq;
+	struct acpi_gsi_descriptor data;
 	unsigned int irq_type = acpi_gsi_get_irq_type(trigger, polarity);
+	struct irq_domain *d = irq_find_acpi_domain(acpi_irq_model,
+						    DOMAIN_BUS_ANY);
 
 	/*
-	 * There is no way at present to look-up the IRQ domain on ACPI,
-	 * hence always create mapping referring to the default domain
-	 * by passing NULL as irq_domain parameter
+	 * Populate the GSI descriptor in a way that matches the way
+	 * the driver expects its of_phandle_args.
 	 */
-	irq = irq_create_mapping(NULL, gsi);
-	if (!irq)
+	switch (acpi_irq_model) {
+	case ACPI_IRQ_MODEL_GIC:
+		if (gsi >= 32) {
+			data.param[0] = 0;
+			data.param[1] = gsi - 32;
+			data.param[2] = irq_type;
+		} else {
+			data.param[0] = 1;
+			data.param[1] = gsi - 16;
+			data.param[2] = 0xff << 4 | irq_type;
+		}
+
+		data.param_count = 3;
+		break;
+	default:
+		pr_warn("Unknown acpi_irq_model = %d\n", acpi_irq_model);
 		return -EINVAL;
+	}
 
-	/* Set irq type if specified and different than the current one */
-	if (irq_type != IRQ_TYPE_NONE &&
-		irq_type != irq_get_trigger_type(irq))
-		irq_set_irq_type(irq, irq_type);
-	return irq;
+	return irq_create_acpi_mapping(d, &data);
 }
 EXPORT_SYMBOL_GPL(acpi_register_gsi);
 
@@ -98,7 +114,9 @@ EXPORT_SYMBOL_GPL(acpi_register_gsi);
  */
 void acpi_unregister_gsi(u32 gsi)
 {
-	int irq = irq_find_mapping(NULL, gsi);
+	struct irq_domain *d = irq_find_acpi_domain(acpi_irq_model,
+						    DOMAIN_BUS_ANY);
+	int irq = irq_find_mapping(d, gsi);
 
 	irq_dispose_mapping(irq);
 }
-- 
2.1.4