Add helper function its_pmsi_prepare_devid() to pave road to support new
DOMAIN_BUS_DEVICE_PCI_EP_MSI. No function change.

Signed-off-by: Frank Li <Frank.Li@nxp.com>
---
change from v12 to v13
- new patch
---
 drivers/irqchip/irq-gic-v3-its-msi-parent.c | 30 ++++++++++++++++++-----------
 1 file changed, 19 insertions(+), 11 deletions(-)

diff --git a/drivers/irqchip/irq-gic-v3-its-msi-parent.c b/drivers/irqchip/irq-gic-v3-its-msi-parent.c
index 75aa0d4bd1346..b2a4b67545b82 100644
--- a/drivers/irqchip/irq-gic-v3-its-msi-parent.c
+++ b/drivers/irqchip/irq-gic-v3-its-msi-parent.c
@@ -132,19 +132,10 @@ int __weak iort_pmsi_get_dev_id(struct device *dev, u32 *dev_id)
 	return -1;
 }
 
-static int its_pmsi_prepare(struct irq_domain *domain, struct device *dev,
-			    int nvec, msi_alloc_info_t *info)
+static int its_pmsi_prepare_devid(struct irq_domain *domain, struct device *dev,
+				  int nvec, msi_alloc_info_t *info, u32 dev_id)
 {
 	struct msi_domain_info *msi_info;
-	u32 dev_id;
-	int ret;
-
-	if (dev->of_node)
-		ret = of_pmsi_get_dev_id(domain->parent, dev, &dev_id);
-	else
-		ret = iort_pmsi_get_dev_id(dev, &dev_id);
-	if (ret)
-		return ret;
 
 	/* ITS specific DeviceID, as the core ITS ignores dev. */
 	info->scratchpad[0].ul = dev_id;
@@ -165,6 +156,23 @@ static int its_pmsi_prepare(struct irq_domain *domain, struct device *dev,
 					  dev, nvec, info);
 }
 
+static int its_pmsi_prepare(struct irq_domain *domain, struct device *dev,
+			    int nvec, msi_alloc_info_t *info)
+{
+	u32 dev_id;
+	int ret;
+
+	if (dev->of_node)
+		ret = of_pmsi_get_dev_id(domain->parent, dev, &dev_id);
+	else
+		ret = iort_pmsi_get_dev_id(dev, &dev_id);
+
+	if (ret)
+		return ret;
+
+	return its_pmsi_prepare_devid(domain, dev, nvec, info, dev_id);
+}
+
 static bool its_init_dev_msi_info(struct device *dev, struct irq_domain *domain,
 				  struct irq_domain *real_parent, struct msi_domain_info *info)
 {

-- 
2.34.1