[PATCH hyperv-next v4 5/6] Drivers: hv: vmbus: Get the IRQ number from DeviceTree

[Roman Kisel]

The VMBus driver uses ACPI for interrupt assignment on
arm64 hence it won't function in the VTL mode where only
DeviceTree can be used.

Update the VMBus driver to discover interrupt configuration
from DT.

Signed-off-by: Roman Kisel <romank at linux.microsoft.com>
---
 drivers/hv/vmbus_drv.c | 36 ++++++++++++++++++++++++++++++++++++
 1 file changed, 36 insertions(+)

diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c
index 0f6cd44fff29..9d0c2dbd2a69 100644
--- a/drivers/hv/vmbus_drv.c
+++ b/drivers/hv/vmbus_drv.c
@@ -2335,6 +2335,36 @@ static int vmbus_acpi_add(struct platform_device *pdev)
 }
 #endif
 
+static int __maybe_unused vmbus_set_irq(struct platform_device *pdev)
+{
+	struct irq_data *data;
+	int irq;
+	irq_hw_number_t hwirq;
+
+	irq = platform_get_irq(pdev, 0);
+	if (irq == 0) {
+		pr_err("VMBus interrupt mapping failure\n");
+		return -EINVAL;
+	}
+	if (irq < 0) {
+		pr_err("VMBus interrupt data can't be read from DeviceTree, error %d\n", irq);
+		return irq;
+	}
+
+	data = irq_get_irq_data(irq);
+	if (!data) {
+		pr_err("No interrupt data for VMBus virq %d\n", irq);
+		return -ENODEV;
+	}
+	hwirq = irqd_to_hwirq(data);
+
+	vmbus_irq = irq;
+	vmbus_interrupt = hwirq;
+	pr_debug("VMBus virq %d, hwirq %d\n", vmbus_irq, vmbus_interrupt);
+
+	return 0;
+}
+
 static int vmbus_device_add(struct platform_device *pdev)
 {
 	struct resource **cur_res = &hyperv_mmio;
@@ -2349,6 +2379,12 @@ static int vmbus_device_add(struct platform_device *pdev)
 	if (ret)
 		return ret;
 
+#ifndef HYPERVISOR_CALLBACK_VECTOR
+	ret = vmbus_set_irq(pdev);
+	if (ret)
+		return ret;
+#endif
+
 	for_each_of_range(&parser, &range) {
 		struct resource *res;
 
-- 
2.43.0