[PATCH RFC 10/11] iommu/arm-smmu-v3: Add 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@xxxxxxxxxx>
Cc: Will Deacon <will@xxxxxxxxxx>
Cc: Robin Murphy <robin.murphy@xxxxxxx>
---
 drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
index 5732f3ba0122..1832389916a4 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
@@ -5562,18 +5562,26 @@ static int arm_smmu_device_probe(struct platform_device *pdev)
 	/* Interrupt lines */
 
 	irq = platform_get_irq_byname_optional(pdev, "combined");
+	if (irq == -EPROBE_DEFER)
+		return dev_err_probe(dev, irq, "failed to get combined IRQ\n");
 	if (irq > 0)
 		smmu->combined_irq = irq;
 	else {
 		irq = platform_get_irq_byname_optional(pdev, "eventq");
+		if (irq == -EPROBE_DEFER)
+			return dev_err_probe(dev, irq, "failed to get eventq IRQ\n");
 		if (irq > 0)
 			smmu->evtq.q.irq = irq;
 
 		irq = platform_get_irq_byname_optional(pdev, "priq");
+		if (irq == -EPROBE_DEFER)
+			return dev_err_probe(dev, irq, "failed to get priq IRQ\n");
 		if (irq > 0)
 			smmu->priq.q.irq = irq;
 
 		irq = platform_get_irq_byname_optional(pdev, "gerror");
+		if (irq == -EPROBE_DEFER)
+			return dev_err_probe(dev, irq, "failed to get gerror IRQ\n");
 		if (irq > 0)
 			smmu->gerr_irq = irq;
 	}

-- 
2.54.0