irqdomain: um: use irq_domain_create_linear() helper

um_pci_init() open-codes what the irq_domain_create_linear() helper
does already. Use the helper instead of open-coding it.

This needs retval checking modification.

Signed-off-by: Jiri Slaby (SUSE) <[email protected]>
Cc: Richard Weinberger <[email protected]>
Cc: Anton Ivanov <[email protected]>
Cc: Johannes Berg <[email protected]>
Cc: [email protected]
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Johannes Berg <[email protected]>

Author: Jiri Slaby (SUSE)

arch/um/drivers/virt-pci.c

@@ -538,11 +538,6 @@ void um_pci_platform_device_unregister(struct um_pci_device *dev)
 
 static int __init um_pci_init(void)
 {
-	struct irq_domain_info inner_domain_info = {
-		.size		= MAX_MSI_VECTORS,
-		.hwirq_max	= MAX_MSI_VECTORS,
-		.ops		= &um_pci_inner_domain_ops,
-	};
 	int err, i;
 
 	WARN_ON(logic_iomem_add_region(&virt_cfgspace_resource,
@@ -564,10 +559,10 @@ static int __init um_pci_init(void)
 		goto free;
 	}
 
-	inner_domain_info.fwnode = um_pci_fwnode;
-	um_pci_inner_domain = irq_domain_instantiate(&inner_domain_info);
-	if (IS_ERR(um_pci_inner_domain)) {
-		err = PTR_ERR(um_pci_inner_domain);
+	um_pci_inner_domain = irq_domain_create_linear(um_pci_fwnode, MAX_MSI_VECTORS,
+						       &um_pci_inner_domain_ops, NULL);
+	if (!um_pci_inner_domain) {
+		err = -ENOMEM;
 		goto free;
 	}
 
@@ -602,7 +597,7 @@ static int __init um_pci_init(void)
 	return 0;
 
 free:
-	if (!IS_ERR_OR_NULL(um_pci_inner_domain))
+	if (um_pci_inner_domain)
 		irq_domain_remove(um_pci_inner_domain);
 	if (um_pci_fwnode)
 		irq_domain_free_fwnode(um_pci_fwnode);