[PATCH RFC 09/11] iommu/arm-smmu: Add arm-smmu IRQ mapping -EPROBE_DEFER handling

[Lorenzo Pieralisi]

With the advent of GICv5, IRQs mapping can fail if the interrupt
controller the wired SMMU interrupts are routed to has not probed
yet when the SMMU driver probes.

Handle -EPROBE_DEFER gracefully for IRQ mappings failures.

Signed-off-by: Lorenzo Pieralisi <lpieralisi at kernel.org>
Cc: Will Deacon <will at kernel.org>
Cc: Robin Murphy <robin.murphy at arm.com>
---
 drivers/iommu/arm/arm-smmu/arm-smmu.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/iommu/arm/arm-smmu/arm-smmu.c b/drivers/iommu/arm/arm-smmu/arm-smmu.c
index 889a0966d36c..a111b80553da 100644
--- a/drivers/iommu/arm/arm-smmu/arm-smmu.c
+++ b/drivers/iommu/arm/arm-smmu/arm-smmu.c
@@ -2154,6 +2154,8 @@ static int arm_smmu_device_probe(struct platform_device *pdev)
 		return PTR_ERR(smmu);
 
 	num_irqs = platform_irq_count(pdev);
+	if (num_irqs < 0)
+		return dev_err_probe(dev, num_irqs, "IRQ count failed\n");
 
 	smmu->num_context_irqs = num_irqs - global_irqs - pmu_irqs;
 	if (smmu->num_context_irqs <= 0)
@@ -2171,7 +2173,7 @@ static int arm_smmu_device_probe(struct platform_device *pdev)
 		int irq = platform_get_irq(pdev, global_irqs + pmu_irqs + i);
 
 		if (irq < 0)
-			return irq;
+			return dev_err_probe(dev, irq, "failed to get context IRQ\n");
 		smmu->irqs[i] = irq;
 	}
 
@@ -2211,7 +2213,7 @@ static int arm_smmu_device_probe(struct platform_device *pdev)
 		int irq = platform_get_irq(pdev, i);
 
 		if (irq < 0)
-			return irq;
+			return dev_err_probe(dev, irq, "failed to get global IRQ\n");
 
 		err = devm_request_irq(dev, irq, global_fault, IRQF_SHARED,
 				       "arm-smmu global fault", smmu);

-- 
2.54.0