[PATCH v3 1/3] irqchip: dw-apb-ictl: prepare for support hierarchy irq domain

[Zhen Lei <thunder.leizhen@xxxxxxxxxx>]

Rename some functions and variables in advance, to make the next patch
looks more clear. The details are as follows:
1. rename dw_apb_ictl_handler() to dw_apb_ictl_handle_irq_cascaded().
2. change (1 << hwirq) to BIT(hwirq).

In function dw_apb_ictl_init():
1. rename local variable irq to parent_irq.
2. add "const struct irq_domain_ops *domain_ops = &irq_generic_chip_ops",
   then replace &irq_generic_chip_ops in other places with domain_ops.

No functional change.

Signed-off-by: Zhen Lei <thunder.leizhen@xxxxxxxxxx>
Tested-by: Haoyu Lv <lvhaoyu@xxxxxxxxxx>
---
 drivers/irqchip/irq-dw-apb-ictl.c | 17 +++++++++--------
 1 file changed, 9 insertions(+), 8 deletions(-)

diff --git a/drivers/irqchip/irq-dw-apb-ictl.c b/drivers/irqchip/irq-dw-apb-ictl.c
index e4550e9c810b..5458004242e9 100644
--- a/drivers/irqchip/irq-dw-apb-ictl.c
+++ b/drivers/irqchip/irq-dw-apb-ictl.c
@@ -26,7 +26,7 @@
 #define APB_INT_FINALSTATUS_H	0x34
 #define APB_INT_BASE_OFFSET	0x04
 
-static void dw_apb_ictl_handler(struct irq_desc *desc)
+static void dw_apb_ictl_handle_irq_cascaded(struct irq_desc *desc)
 {
 	struct irq_domain *d = irq_desc_get_handler_data(desc);
 	struct irq_chip *chip = irq_desc_get_chip(desc);
@@ -43,7 +43,7 @@ static void dw_apb_ictl_handler(struct irq_desc *desc)
 			u32 virq = irq_find_mapping(d, gc->irq_base + hwirq);
 
 			generic_handle_irq(virq);
-			stat &= ~(1 << hwirq);
+			stat &= ~BIT(hwirq);
 		}
 	}
 
@@ -73,12 +73,13 @@ static int __init dw_apb_ictl_init(struct device_node *np,
 	struct irq_domain *domain;
 	struct irq_chip_generic *gc;
 	void __iomem *iobase;
-	int ret, nrirqs, irq, i;
+	int ret, nrirqs, parent_irq, i;
 	u32 reg;
+	const struct irq_domain_ops *domain_ops = &irq_generic_chip_ops;
 
 	/* Map the parent interrupt for the chained handler */
-	irq = irq_of_parse_and_map(np, 0);
-	if (irq <= 0) {
+	parent_irq = irq_of_parse_and_map(np, 0);
+	if (parent_irq <= 0) {
 		pr_err("%pOF: unable to parse irq\n", np);
 		return -EINVAL;
 	}
@@ -120,8 +121,7 @@ static int __init dw_apb_ictl_init(struct device_node *np,
 	else
 		nrirqs = fls(readl_relaxed(iobase + APB_INT_ENABLE_L));
 
-	domain = irq_domain_add_linear(np, nrirqs,
-				       &irq_generic_chip_ops, NULL);
+	domain = irq_domain_add_linear(np, nrirqs, domain_ops, NULL);
 	if (!domain) {
 		pr_err("%pOF: unable to add irq domain\n", np);
 		ret = -ENOMEM;
@@ -146,7 +146,8 @@ static int __init dw_apb_ictl_init(struct device_node *np,
 		gc->chip_types[0].chip.irq_resume = dw_apb_ictl_resume;
 	}
 
-	irq_set_chained_handler_and_data(irq, dw_apb_ictl_handler, domain);
+	irq_set_chained_handler_and_data(parent_irq,
+				dw_apb_ictl_handle_irq_cascaded, domain);
 
 	return 0;
 
-- 
2.26.0.106.g9fadedd