[RFC PATCH 2/4] irqchip/fsl-mc: Change the way the IRQ domain is set for MC devices

[laurentiu.tudor@nxp.com]

From: Diana Craciun <diana.craciun@oss.nxp.com>

In ACPI the MC bus is represented as a platform device and a named
component in the IORT table. The mc-bus devices are discovered
dynamically at runtime but they share the same fwnode with the parent
platfom device. This patch changes the way the IRQ domain is searched
for the MC devices: it takes the fwnode reference from the parent and
uses the fwnode reference to find the MC IRQ domain.

Signed-off-by: Diana Craciun <diana.craciun@oss.nxp.com>
---
 drivers/bus/fsl-mc/fsl-mc-msi.c | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/drivers/bus/fsl-mc/fsl-mc-msi.c b/drivers/bus/fsl-mc/fsl-mc-msi.c
index 8b9c66d7c4ff..1e2e97329781 100644
--- a/drivers/bus/fsl-mc/fsl-mc-msi.c
+++ b/drivers/bus/fsl-mc/fsl-mc-msi.c
@@ -182,16 +182,23 @@ int fsl_mc_find_msi_domain(struct device *mc_platform_dev,
 {
 	struct irq_domain *msi_domain;
 	struct device_node *mc_of_node = mc_platform_dev->of_node;
+	struct fwnode_handle *fwnode;
 
-	msi_domain = of_msi_get_domain(mc_platform_dev, mc_of_node,
-				       DOMAIN_BUS_FSL_MC_MSI);
+	msi_domain = dev_get_msi_domain(mc_platform_dev);
 	if (!msi_domain) {
 		pr_err("Unable to find fsl-mc MSI domain for %pOF\n",
 		       mc_of_node);
 
 		return -ENOENT;
 	}
+	fwnode = msi_domain->fwnode;
+	msi_domain = irq_find_matching_fwnode(fwnode, DOMAIN_BUS_FSL_MC_MSI);
+	if (!msi_domain) {
+		pr_err("Unable to find fsl-mc MSI domain for %pOF\n",
+		       mc_of_node);
 
+		return -ENOENT;
+	}
 	*mc_msi_domain = msi_domain;
 	return 0;
 }
-- 
2.17.1