[PATCH 1/2] iommu/arm-smmu: Use platform_irq_count() to get the interrupt count

[Lad Prabhakar]

platform_get_resource(pdev, IORESOURCE_IRQ, ..) relies on static
allocation of IRQ resources in DT core code, this causes an issue
when using hierarchical interrupt domains using "interrupts" property
in the node as this bypasses the hierarchical setup and messes up the
irq chaining.

In preparation for removal of static setup of IRQ resource from DT core
code use platform_get_irq_count().

Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj at bp.renesas.com>
---
 drivers/iommu/arm/arm-smmu/arm-smmu.c | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/drivers/iommu/arm/arm-smmu/arm-smmu.c b/drivers/iommu/arm/arm-smmu/arm-smmu.c
index 4bc75c4ce402..4844cd075644 100644
--- a/drivers/iommu/arm/arm-smmu/arm-smmu.c
+++ b/drivers/iommu/arm/arm-smmu/arm-smmu.c
@@ -2105,12 +2105,12 @@ static int arm_smmu_device_probe(struct platform_device *pdev)
 	if (IS_ERR(smmu))
 		return PTR_ERR(smmu);
 
-	num_irqs = 0;
-	while ((res = platform_get_resource(pdev, IORESOURCE_IRQ, num_irqs))) {
-		num_irqs++;
-		if (num_irqs > smmu->num_global_irqs)
-			smmu->num_context_irqs++;
-	}
+	num_irqs = platform_irq_count(pdev);
+	if (num_irqs < 0)
+		return num_irqs;
+
+	if (num_irqs > smmu->num_global_irqs)
+		smmu->num_context_irqs += (num_irqs - smmu->num_global_irqs);
 
 	if (!smmu->num_context_irqs) {
 		dev_err(dev, "found %d interrupts but expected at least %d\n",
-- 
2.17.1